The present invention relates to an organic electroluminescence device and an electronic device.
An organic electroluminescence device (hereinafter, occasionally referred to as “organic EL device”) has found its application in a full-color display for mobile phones, televisions and the like. When a voltage is applied to an organic EL device, holes and electrons are injected from an anode and a cathode, respectively, into an emitting layer. The injected holes and electrons are recombined in the emitting layer to form excitons. Specifically, according to the electron spin statistics theory, singlet excitons and triplet excitons are generated at a ratio of 25%:75%.
Various studies have been made for compounds to be used for the organic EL device in order to enhance the performance of the organic EL device (see, for instance, Patent Literature 1: JP 2013-157552 A, Patent Literature 2: WO 2004/018587 A, Patent Literature 3: WO 2005/115950 A, Patent Literature 4: WO 2011/077691 A, Patent Literature 5: JP 2018-125504 A, and Patent Literature 6: US 2019/280209 A). For instance, layering a plurality of emitting layers has been studied in Patent Literature 6 and Patent Literature 7 (JP 2007-294261 A). In addition, Patent Literature 8 (WO 2010/134350 A) describes a phenomenon where singlet excitons are generated by collision and fusion of two triplet excitons (hereinafter, occasionally referred to as a Triplet-Triplet Fusion (TTF) phenomenon) in order to improve the performance of the organic EL device. The performance of the organic EL device is evaluable in terms of, for instance, luminance, emission wavelength, chromaticity, luminous efficiency, drive voltage, and lifetime.
Recently, studies have been made on the arrangement of an organic EL device including a plurality of emitting units that are layered with a charge generating unit interposed therebetween and are connected in series. Such an arrangement of the organic EL device is occasionally referred to as a tandem organic EL device. The tandem organic EL device may be decreased in device performance (e.g., a luminous efficiency) when being driven at a low current density (of 1 mA/cm2 or less, such as about 0.01 mA/cm2).
An object of the invention is to provide an organic electroluminescence device capable of preventing a decrease in device performance at a low current density and an electronic device including the organic electroluminescence device.
According to an aspect of the invention, there is provided an organic electroluminescence device including: an anode;
a cathode;
two or more emitting units provided between the anode and the cathode; one or more charge generating units provided between the two or more emitting units;
a first organic layer provided between the anode and an anode side emitting unit, the anode side emitting unit being one closer to the anode of the two or more emitting units; and
a second organic layer provided between the first organic layer and the anode, in which
the anode side emitting unit includes a first emitting layer containing a first host material,
the first emitting layer is provided close to the anode in the anode side emitting unit,
the first organic layer and the first emitting layer are in direct contact with each other,
the first organic layer and the second organic layer are in direct contact with each other,
the second organic layer and the anode are in direct contact with each other,
the first organic layer has a film thickness of 40 nm or less,
the first organic layer includes a first organic material, and
a difference between an ionization potential Ip(H1) of the first host material and an ionization potential Ip(EBL) of the first organic material satisfies a relationship of a numerical formula (Numerical Formula A1) below.
Ip(H1)−Ip(EBL)≤0.4 eV (Numerical Formula A1)
According to another aspect of the invention, an electronic device including the organic electroluminescence device according to the above aspect of the invention is provided.
According to the above aspects of the invention, an organic electroluminescence device capable of preventing a decrease in device performance at a low current density and an electronic device including the organic electroluminescence device can be provided.
Herein, a hydrogen atom includes isotopes having different numbers of neutrons, specifically, protium, deuterium and tritium.
In chemical formulae herein, it is assumed that a hydrogen atom (i.e. protium, deuterium and tritium) is bonded to each of bondable positions that are not annexed with signs “R” or the like or “D” representing a deuterium.
Herein, the ring carbon atoms refer to the number of carbon atoms among atoms forming a ring of a compound (e.g., a monocyclic compound, fused-ring compound, cross-linking compound, carbon ring compound, and heterocyclic compound) in which the atoms are bonded to each other to form the ring. When the ring is substituted by a substituent(s), carbon atom(s) contained in the substituent(s) is not counted in the ring carbon atoms. Unless otherwise specified, the same applies to the “ring carbon atoms” described later. For instance, a benzene ring has 6 ring carbon atoms, a naphthalene ring has 10 ring carbon atoms, a pyridine ring has 5 ring carbon atoms, and a furan ring has 4 ring carbon atoms. Further, for instance, 9,9-diphenylfluorenyl group has 13 ring carbon atoms and 9,9′-spirobifluorenyl group has 25 ring carbon atoms.
When a benzene ring is substituted by a substituent in a form of, for instance, an alkyl group, the number of carbon atoms of the alkyl group is not counted in the number of the ring carbon atoms of the benzene ring. Accordingly, the benzene ring substituted by an alkyl group has 6 ring carbon atoms. When a naphthalene ring is substituted by a substituent in a form of, for instance, an alkyl group, the number of carbon atoms of the alkyl group is not counted in the number of the ring carbon atoms of the naphthalene ring. Accordingly, the naphthalene ring substituted by an alkyl group has 10 ring carbon atoms.
Herein, the ring atoms refer to the number of atoms forming a ring of a compound (e.g., a monocyclic compound, fused-ring compound, cross-linking compound, carbon ring compound, and heterocyclic compound) in which the atoms are bonded to each other to form the ring (e.g., monocyclic ring, fused ring, and ring assembly). Atom(s) not forming the ring (e.g., hydrogen atom(s) for saturating the valence of the atom which forms the ring) and atom(s) in a substituent by which the ring is substituted are not counted as the ring atoms. Unless otherwise specified, the same applies to the “ring atoms” described later. For instance, a pyridine ring has 6 ring atoms, a quinazoline ring has 10 ring atoms, and a furan ring has 5 ring atoms. For instance, the number of hydrogen atom(s) bonded to a pyridine ring or the number of atoms forming a substituent are not counted as the pyridine ring atoms. Accordingly, a pyridine ring bonded to a hydrogen atom(s) or a substituent(s) has 6 ring atoms. For instance, the hydrogen atom(s) bonded to carbon atom(s) of a quinazoline ring or the atoms forming a substituent are not counted as the quinazoline ring atoms. Accordingly, a quinazoline ring bonded to hydrogen atom(s) or a substituent(s) has 10 ring atoms.
Herein, “XX to YY carbon atoms” in the description of “substituted or unsubstituted ZZ group having XX to YY carbon atoms” represent carbon atoms of an unsubstituted ZZ group and do not include carbon atoms of a substituent(s) of the substituted ZZ group. Herein, “YY” is larger than “XX,” “XX” representing an integer of 1 or more and “YY” representing an integer of 2 or more.
Herein, “XX to YY atoms” in the description of “substituted or unsubstituted ZZ group having XX to YY atoms” represent atoms of an unsubstituted ZZ group and do not include atoms of a substituent(s) of the substituted ZZ group. Herein, “YY” is larger than “XX,” “XX” representing an integer of 1 or more and “YY” representing an integer of 2 or more.
Herein, an unsubstituted ZZ group refers to an “unsubstituted ZZ group” in a “substituted or unsubstituted ZZ group,” and a substituted ZZ group refers to a “substituted ZZ group” in a “substituted or unsubstituted ZZ group.”
Herein, the term “unsubstituted” used in a “substituted or unsubstituted ZZ group” means that a hydrogen atom(s) in the ZZ group is not substituted with a substituent(s). The hydrogen atom(s) in the “unsubstituted ZZ group” is protium, deuterium, or tritium.
Herein, the term “substituted” used in a “substituted or unsubstituted ZZ group” means that at least one hydrogen atom in the ZZ group is substituted with a substituent. Similarly, the term “substituted” used in a “BB group substituted by AA group” means that at least one hydrogen atom in the BB group is substituted with the AA group.
Substituents mentioned herein will be described below.
An “unsubstituted aryl group” mentioned herein has, unless otherwise specified herein, 6 to 50, preferably 6 to 30, more preferably 6 to 18 ring carbon atoms.
An “unsubstituted heterocyclic group” mentioned herein has, unless otherwise specified herein, 5 to 50, preferably 5 to 30, more preferably 5 to 18 ring atoms.
An “unsubstituted alkyl group” mentioned herein has, unless otherwise specified herein, 1 to 50, preferably 1 to 20, more preferably 1 to 6 carbon atoms.
An “unsubstituted alkenyl group” mentioned herein has, unless otherwise specified herein, 2 to 50, preferably 2 to 20, more preferably 2 to 6 carbon atoms.
An “unsubstituted alkynyl group” mentioned herein has, unless otherwise specified herein, 2 to 50, preferably 2 to 20, more preferably 2 to 6 carbon atoms.
An “unsubstituted cycloalkyl group” mentioned herein has, unless otherwise specified herein, 3 to 50, preferably 3 to 20, more preferably 3 to 6 ring carbon atoms.
An “unsubstituted arylene group” mentioned herein has, unless otherwise specified herein, 6 to 50, preferably 6 to 30, more preferably 6 to 18 ring carbon atoms.
An “unsubstituted divalent heterocyclic group” mentioned herein has, unless otherwise specified herein, 5 to 50, preferably 5 to 30, more preferably 5 to 18 ring atoms.
An “unsubstituted alkylene group” mentioned herein has, unless otherwise specified herein, 1 to 50, preferably 1 to 20, more preferably 1 to 6 carbon atoms.
Specific examples (specific example group G1) of the “substituted or unsubstituted aryl group” mentioned herein include unsubstituted aryl groups (specific example group G1A) below and substituted aryl groups (specific example group G1B) below. (Herein, an unsubstituted aryl group refers to an “unsubstituted aryl group” in a “substituted or unsubstituted aryl group”, and a substituted aryl group refers to a “substituted aryl group” in a “substituted or unsubstituted aryl group.”) A simply termed “aryl group” herein includes both of an “unsubstituted aryl group” and a “substituted aryl group.”
The “substituted aryl group” refers to a group derived by substituting at least one hydrogen atom in an “unsubstituted aryl group” with a substituent. Examples of the “substituted aryl group” include a group derived by substituting at least one hydrogen atom in the “unsubstituted aryl group” in the specific example group G1A below with a substituent, and examples of the substituted aryl group in the specific example group G1B below. It should be noted that the examples of the “unsubstituted aryl group” and the “substituted aryl group” mentioned herein are merely exemplary, and the “substituted aryl group” mentioned herein includes a group derived by further substituting a hydrogen atom bonded to a carbon atom of a skeleton of a “substituted aryl group” in the specific example group G1B below, and a group derived by further substituting a hydrogen atom of a substituent of the “substituted aryl group” in the specific example group G1B below.
phenyl group, p-biphenyl group, m-biphenyl group, o-biphenyl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-terphenyl-4-yl group, o-terphenyl-3-yl group, o-terphenyl-2-yl group, 1-naphthyl group, 2-naphthyl group, anthryl group, benzanthryl group, phenanthryl group, benzophenanthryl group, phenalenyl group, pyrenyl group, chrysenyl group, benzochrysenyl group, triphenylenyl group, benzotriphenylenyl group, tetracenyl group, pentacenyl group, fluorenyl group, 9,9′-spirobifluorenyl group, benzofluorenyl group, dibenzofluorenyl group, fluoranthenyl group, benzofluoranthenyl group, perylenyl group, and a monovalent aryl group derived by removing one hydrogen atom from cyclic structures represented by formulae (TEMP-1) to (TEMP-15) below.
o-tolyl group, m-tolyl group, p-tolyl group, para-xylyl group, meta-xylyl group, ortho-xylyl group, para-isopropylphenyl group, meta-isopropylphenyl group, ortho-isopropylphenyl group, para-t-butylphenyl group, meta-t-butylphenyl group, ortho-t-butylphenyl group, 3,4,5-trimethylphenyl group, 9,9-dimethylfluorenyl group, 9,9-diphenylfluorenyl group, 9,9-bis(4-methylphenyl)fluorenyl group, 9,9-bis(4-isopropylphenyl)fluorenyl group, 9,9-bis(4-t-butylphenyl)fluorenyl group, cyanophenyl group, triphenylsilylphenyl group, trimethylsilylphenyl group, phenylnaphthyl group, naphthylphenyl group, and a group derived by substituting at least one hydrogen atom of a monovalent group derived from one of the cyclic structures represented by the formulae (TEMP-1) to (TEMP-15) with a substituent.
The “heterocyclic group” mentioned herein refers to a cyclic group having at least one hetero atom in the ring atoms. Specific examples of the hetero atom include a nitrogen atom, oxygen atom, sulfur atom, silicon atom, phosphorus atom, and boron atom.
The “heterocyclic group” mentioned herein is a monocyclic group or a fused-ring group.
The “heterocyclic group” mentioned herein is an aromatic heterocyclic group or a non-aromatic heterocyclic group.
Specific examples (specific example group G2) of the “substituted or unsubstituted heterocyclic group” mentioned herein include unsubstituted heterocyclic groups (specific example group G2A) and substituted heterocyclic groups (specific example group G2B). (Herein, an unsubstituted heterocyclic group refers to an “unsubstituted heterocyclic group” in a “substituted or unsubstituted heterocyclic group,” and a substituted heterocyclic group refers to a “substituted heterocyclic group” in a “substituted or unsubstituted heterocyclic group.”) A simply termed “heterocyclic group” herein includes both of “unsubstituted heterocyclic group” and “substituted heterocyclic group.”
The “substituted heterocyclic group” refers to a group derived by substituting at least one hydrogen atom in an “unsubstituted heterocyclic group” with a substituent. Specific examples of the “substituted heterocyclic group” include a group derived by substituting at least one hydrogen atom in the “unsubstituted heterocyclic group” in the specific example group G2A below with a substituent, and examples of the substituted heterocyclic group in the specific example group G2B below. It should be noted that the examples of the “unsubstituted heterocyclic group” and the “substituted heterocyclic group” mentioned herein are merely exemplary, and the “substituted heterocyclic group” mentioned herein includes a group derived by further substituting a hydrogen atom bonded to a ring atom of a skeleton of a “substituted heterocyclic group” in the specific example group G2B below, and a group derived by further substituting a hydrogen atom of a substituent of the “substituted heterocyclic group” in the specific example group G2B below.
The specific example group G2A includes, for instance, unsubstituted heterocyclic groups including a nitrogen atom (specific example group G2A1) below, unsubstituted heterocyclic groups including an oxygen atom (specific example group G2A2) below, unsubstituted heterocyclic groups including a sulfur atom (specific example group G2A3) below, and monovalent heterocyclic groups (specific example group G2A4) derived by removing a hydrogen atom from cyclic structures represented by formulae (TEMP-16) to (TEMP-33) below.
The specific example group G2B includes, for instance, substituted heterocyclic groups including a nitrogen atom (specific example group G2B1) below, substituted heterocyclic groups including an oxygen atom (specific example group G2B2) below, substituted heterocyclic groups including a sulfur atom (specific example group G2B3) below, and groups derived by substituting at least one hydrogen atom of the monovalent heterocyclic groups (specific example group G2B4) derived from the cyclic structures represented by formulae (TEMP-16) to (TEMP-33) below.
pyrrolyl group, imidazolyl group, pyrazolyl group, triazolyl group, tetrazolyl group, oxazolyl group, isoxazolyl group, oxadiazolyl group, thiazolyl group, isothiazolyl group, thiadiazolyl group, pyridyl group, pyridazynyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, indolyl group, isoindolyl group, indolizinyl group, quinolizinyl group, quinolyl group, isoquinolyl group, cinnolyl group, phthalazinyl group, quinazolinyl group, quinoxalinyl group, benzimidazolyl group, indazolyl group, phenanthrolinyl group, phenanthridinyl group, acridinyl group, phenazinyl group, carbazolyl group, benzocarbazolyl group, morpholino group, phenoxazinyl group, phenothiazinyl group, azacarbazolyl group, and diazacarbazolyl group.
furyl group, oxazolyl group, isoxazolyl group, oxadiazolyl group, xanthenyl group, benzofuranyl group, isobenzofuranyl group, a dibenzofuranyl group, naphthobenzofuranyl group, benzoxazolyl group, benzisoxazolyl group, phenoxazinyl group, morpholino group, dinaphthofuranyl group, azadibenzofuranyl group, diazadibenzofuranyl group, azanaphthobenzofuranyl group, and diazanaphthobenzofuranyl group.
thienyl group, thiazolyl group, isothiazolyl group, thiadiazolyl group, benzothiophenyl group (benzothienyl group), isobenzothiophenyl group (isobenzothienyl group), dibenzothiophenyl group (dibenzothienyl group), naphthobenzothiophenyl group (nahthobenzothienyl group), benzothiazolyl group, benzisothiazolyl group, phenothiazinyl group, dinaphthothiophenyl group (dinaphthothienyl group), azadibenzothiophenyl group (azadibenzothienyl group), diazadibenzothiophenyl group (diazadibenzothienyl group), azanaphthobenzothiophenyl group (azanaphthobenzothienyl group), and diazanaphthobenzothiophenyl group (diazanaphthobenzothienyl group).
Monovalent Heterocyclic Groups Derived by Removing One Hydrogen Atom from Cyclic Structures Represented by Formulae (TEMP-16) to (TEMP-33) (Specific Example Group G2A4):
In the formulae (TEMP-16) to (TEMP-33), XA and YA are each independently an oxygen atom, a sulfur atom, NH, or CH2, with a proviso that at least one of XA or YA is an oxygen atom, a sulfur atom, or NH.
When at least one of XA or YA in the formulae (TEMP-16) to (TEMP-33) is NH or CH2, the monovalent heterocyclic groups derived from the cyclic structures represented by the formulae (TEMP-16) to (TEMP-33) include a monovalent group derived by removing one hydrogen atom from NH or CH2.
(9-phenyl)carbazolyl group, (9-biphenylyl)carbazolyl group, (9-phenyl)phenylcarbazolyl group, (9-naphthyl)carbazolyl group, diphenylcarbazole-9-yl group, phenylcarbazole-9-yl group, methylbenzimidazolyl group, ethylbenzimidazolyl group, phenyltriazinyl group, biphenylyltriazinyl group, diphenyltriazinyl group, phenylquinazolinyl group, and biphenylquinazolinyl group.
phenyldibenzofuranyl group, methyldibenzofuranyl group, t-butyldibenzofuranyl group, and monovalent residue of spiro[9H-xanthene-9,9′-[9H]fluorene].
phenyldibenzothiophenyl group, methyldibenzothiophenyl group, t-butyldibenzothiophenyl group, and monovalent residue of spiro[9H-thioxanthene-9,9′-[9H]fluorene].
Groups Obtained by Substituting at Least One Hydrogen Atom of Monovalent Heterocyclic Group Derived from Cyclic Structures Represented by Formulae (TEMP-16) to (TEMP-33) with Substituent (Specific Example Group G2B4):
The “at least one hydrogen atom of a monovalent heterocyclic group” means at least one hydrogen atom selected from a hydrogen atom bonded to a ring carbon atom of the monovalent heterocyclic group, a hydrogen atom bonded to a nitrogen atom of at least one of XA or YA in a form of NH, and a hydrogen atom of one of XA and YA in a form of a methylene group (CH2).
Specific examples (specific example group G3) of the “substituted or unsubstituted alkyl group” mentioned herein include unsubstituted alkyl groups (specific example group G3A) and substituted alkyl groups (specific example group G3B) below. (Herein, an unsubstituted alkyl group refers to an “unsubstituted alkyl group” in a “substituted or unsubstituted alkyl group,” and a substituted alkyl group refers to a “substituted alkyl group” in a “substituted or unsubstituted alkyl group.”) A simply termed “alkyl group” herein includes both of “unsubstituted alkyl group” and “substituted alkyl group.”
The “substituted alkyl group” refers to a group derived by substituting at least one hydrogen atom in an “unsubstituted alkyl group” with a substituent. Specific examples of the “substituted alkyl group” include a group derived by substituting at least one hydrogen atom of an “unsubstituted alkyl group” (specific example group G3A) below with a substituent, and examples of the substituted alkyl group (specific example group G3B) below. Herein, the alkyl group for the “unsubstituted alkyl group” refers to a chain alkyl group. Accordingly, the “unsubstituted alkyl group” include linear “unsubstituted alkyl group” and branched “unsubstituted alkyl group.” It should be noted that the examples of the “unsubstituted alkyl group” and the “substituted alkyl group” mentioned herein are merely exemplary, and the “substituted alkyl group” mentioned herein includes a group derived by further substituting a hydrogen atom of a skeleton of the “substituted alkyl group” in the specific example group G3B, and a group derived by further substituting a hydrogen atom of a substituent of the “substituted alkyl group” in the specific example group G3B.
methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, and t-butyl group.
heptafluoropropyl group (including isomer thereof), pentafluoroethyl group, 2,2,2-trifluoroethyl group, and trifluoromethyl group.
Specific examples (specific example group G4) of the “substituted or unsubstituted alkenyl group” mentioned herein include unsubstituted alkenyl groups (specific example group G4A) and substituted alkenyl groups (specific example group G4B). (Herein, an unsubstituted alkenyl group refers to an “unsubstituted alkenyl group” in a “substituted or unsubstituted alkenyl group,” and a substituted alkenyl group refers to a “substituted alkenyl group” in a “substituted or unsubstituted alkenyl group.”) A simply termed “alkenyl group” herein includes both of “unsubstituted alkenyl group” and “substituted alkenyl group.”
The “substituted alkenyl group” refers to a group derived by substituting at least one hydrogen atom in an “unsubstituted alkenyl group” with a substituent. Specific examples of the “substituted alkenyl group” include an “unsubstituted alkenyl group” (specific example group G4A) substituted by a substituent, and examples of the substituted alkenyl group (specific example group G4B) below. It should be noted that the examples of the “unsubstituted alkenyl group” and the “substituted alkenyl group” mentioned herein are merely exemplary, and the “substituted alkenyl group” mentioned herein includes a group derived by further substituting a hydrogen atom of a skeleton of the “substituted alkenyl group” in the specific example group G4B with a substituent, and a group derived by further substituting a hydrogen atom of a substituent of the “substituted alkenyl group” in the specific example group G4B with a substituent.
vinyl group, allyl group, 1-butenyl group, 2-butenyl group, and 3-butenyl group.
1,3-butanedienyl group, 1-methylvinyl group, 1-methylallyl group, 1,1-dimethylallyl group, 2-methylallyl group, and 1,2-dimethylallyl group.
Specific examples (specific example group G5) of the “substituted or unsubstituted alkynyl group” mentioned herein include unsubstituted alkynyl groups (specific example group G5A) below. (Herein, an unsubstituted alkynyl group refers to an “unsubstituted alkynyl group” in a “substituted or unsubstituted alkynyl group.”) A simply termed “alkynyl group” herein includes both of “unsubstituted alkynyl group” and “substituted alkynyl group.”
The “substituted alkynyl group” refers to a group derived by substituting at least one hydrogen atom in an “unsubstituted alkynyl group” with a substituent. Specific examples of the “substituted alkynyl group” include a group derived by substituting at least one hydrogen atom of the “unsubstituted alkynyl group” (specific example group G5A) below with a substituent.
ethynyl group
Specific examples (specific example group G6) of the “substituted or unsubstituted cycloalkyl group” mentioned herein include unsubstituted cycloalkyl groups (specific example group G6A) and substituted cycloalkyl groups (specific example group G6B). (Herein, an unsubstituted cycloalkyl group refers to an “unsubstituted cycloalkyl group” in a “substituted or unsubstituted cycloalkyl group,” and a substituted cycloalkyl group refers to a “substituted cycloalkyl group” in a “substituted or unsubstituted cycloalkyl group.”) A simply termed “cycloalkyl group” herein includes both of “unsubstituted cycloalkyl group” and “substituted cycloalkyl group.”
The “substituted cycloalkyl group” refers to a group derived by substituting at least one hydrogen atom of an “unsubstituted cycloalkyl group” with a substituent. Specific examples of the “substituted cycloalkyl group” include a group derived by substituting at least one hydrogen atom of the “unsubstituted cycloalkyl group” (specific example group G6A) below with a substituent, and examples of the substituted cycloalkyl group (specific example group G6B) below. It should be noted that the examples of the “unsubstituted cycloalkyl group” and the “substituted cycloalkyl group” mentioned herein are merely exemplary, and the “substituted cycloalkyl group” mentioned herein includes a group derived by substituting at least one hydrogen atom bonded to a carbon atom of a skeleton of the “substituted cycloalkyl group” in the specific example group G6B with a substituent, and a group derived by further substituting a hydrogen atom of a substituent of the “substituted cycloalkyl group” in the specific example group G6B with a substituent.
cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, 1-adamantyl group, 2-adamantyl group, 1-norbornyl group, and 2-norbornyl group.
4-methylcyclohexyl group.
Group Represented by —Si(R901)(R902)(R903)
Specific examples (specific example group G7) of the group represented herein by —Si(R901)(R902)(R903) include: —Si(G1)(G1)(G1); —Si(G1)(G2)(G2); —Si(G1)(G1)(G2); —Si(G2)(G2)(G2); —Si(G3)(G3)(G3); and —Si(G6)(G6)(G6), where:
G1 represents a “substituted or unsubstituted aryl group” in the specific example group G1;
G2 represents a “substituted or unsubstituted heterocyclic group” in the specific example group G2;
G3 represents a “substituted or unsubstituted alkyl group” in the specific example group G3;
G6 represents a “substituted or unsubstituted cycloalkyl group” in the specific example group G6;
a plurality of G1 in —Si(G1)(G1)(G1) are mutually the same or different;
a plurality of G2 in —Si(G1)(G2)(G2) are mutually the same or different;
a plurality of G1 in —Si(G1)(G1)(G2) are mutually the same or different;
a plurality of G2 in —Si(G2)(G2)(G2) are mutually the same or different;
a plurality of G3 in —Si(G3)(G3)(G3) are mutually the same or different; and
a plurality of G6 in —Si(G6)(G6)(G6) are mutually the same or different.
Specific examples (specific example group G8) of a group represented by —O—(R904) herein include: —O(G1); —O(G2); —O(G3); and —O(G6), where:
G1 represents a “substituted or unsubstituted aryl group” in the specific example group G1;
G2 represents a “substituted or unsubstituted heterocyclic group” in the specific example group G2;
G3 represents a “substituted or unsubstituted alkyl group” in the specific example group G3; and
G6 represents a “substituted or unsubstituted cycloalkyl group” in the specific example group G6.
Specific examples (specific example group G9) of a group represented herein by —S—(R905) include: —S(G1); —S(G2); —S(G3); and —S(G6), where:
G1 represents a “substituted or unsubstituted aryl group” in the specific example group G1;
G2 represents a “substituted or unsubstituted heterocyclic group” in the specific example group G2;
G3 represents a “substituted or unsubstituted alkyl group” in the specific example group G3; and
G6 represents a “substituted or unsubstituted cycloalkyl group” in the specific example group G6.
Group Represented by —N(R906)(R907)
Specific examples (specific example group G10) of a group represented herein by —N(R906)(R907) include: —N(G1)(G1); —N(G2)(G2); —N(G1)(G2); —N(G3)(G3); and —N(G6)(G6), where:
G1 represents a “substituted or unsubstituted aryl group” in the specific example group G1;
G2 represents a “substituted or unsubstituted heterocyclic group” in the specific example group G2;
G3 represents a “substituted or unsubstituted alkyl group” in the specific example group G3;
G6 represents a “substituted or unsubstituted cycloalkyl group” in the specific example group G6;
a plurality of G1 in —N(G1)(G1) are mutually the same or different;
a plurality of G2 in —N(G2)(G2) are mutually the same or different;
a plurality of G3 in —N(G3)(G3) are mutually the same or different; and
a plurality of G6 in —N(G6)(G6) are mutually the same or different.
Specific examples (specific example group G11) of “halogen atom” mentioned herein include a fluorine atom, chlorine atom, bromine atom, and iodine atom.
The “substituted or unsubstituted fluoroalkyl group” mentioned herein refers to a group derived by substituting at least one hydrogen atom bonded to at least one of carbon atoms forming an alkyl group in the “substituted or unsubstituted alkyl group” with a fluorine atom, and also includes a group (perfluoro group) derived by substituting all of hydrogen atoms bonded to carbon atoms forming the alkyl group in the “substituted or unsubstituted alkyl group” with fluorine atoms. An “unsubstituted fluoroalkyl group” has, unless otherwise specified herein, 1 to 50, preferably 1 to 30, more preferably 1 to 18 carbon atoms. The “substituted fluoroalkyl group” refers to a group derived by substituting at least one hydrogen atom in a “fluoroalkyl group” with a substituent. It should be noted that the examples of the “substituted fluoroalkyl group” mentioned herein include a group derived by further substituting at least one hydrogen atom bonded to a carbon atom of an alkyl chain of a “substituted fluoroalkyl group” with a substituent, and a group derived by further substituting at least one hydrogen atom of a substituent of the “substituted fluoroalkyl group” with a substituent. Specific examples of the “substituted fluoroalkyl group” include a group derived by substituting at least one hydrogen atom of the “alkyl group” (specific example group G3) with a fluorine atom.
The “substituted or unsubstituted haloalkyl group” mentioned herein refers to a group derived by substituting at least one hydrogen atom bonded to carbon atoms forming the alkyl group in the “substituted or unsubstituted alkyl group” with a halogen atom, and also includes a group derived by substituting all hydrogen atoms bonded to carbon atoms forming the alkyl group in the “substituted or unsubstituted alkyl group” with halogen atoms. An “unsubstituted haloalkyl group” has, unless otherwise specified herein, 1 to 50, preferably 1 to 30, more preferably 1 to 18 carbon atoms. The “substituted haloalkyl group” refers to a group derived by substituting at least one hydrogen atom in a “haloalkyl group” with a substituent. It should be noted that the examples of the “substituted haloalkyl group” mentioned herein include a group derived by further substituting at least one hydrogen atom bonded to a carbon atom of an alkyl chain of a “substituted haloalkyl group” with a substituent, and a group derived by further substituting at least one hydrogen atom of a substituent of the “substituted haloalkyl group” with a substituent. Specific examples of the “unsubstituted haloalkyl group” include a group derived by substituting at least one hydrogen atom of the “alkyl group” (specific example group G3) with a halogen atom. The haloalkyl group is sometimes referred to as a halogenated alkyl group.
Specific examples of a “substituted or unsubstituted alkoxy group” mentioned herein include a group represented by —O(G3), G3 being the “substituted or unsubstituted alkyl group” in the specific example group G3. An “unsubstituted alkoxy group” has, unless otherwise specified herein, 1 to 50, preferably 1 to 30, more preferably 1 to 18 carbon atoms.
Specific examples of a “substituted or unsubstituted alkylthio group” mentioned herein include a group represented by —S(G3), G3 being the “substituted or unsubstituted alkyl group” in the specific example group G3. An “unsubstituted alkylthio group” has, unless otherwise specified herein, 1 to 50, preferably 1 to 30, more preferably 1 to 18 carbon atoms.
Specific examples of a “substituted or unsubstituted aryloxy group” mentioned herein include a group represented by —O(G1), G1 being the “substituted or unsubstituted aryl group” in the specific example group G1. An “unsubstituted aryloxy group” has, unless otherwise specified herein, 6 to 50, preferably 6 to 30, more preferably 6 to 18 ring carbon atoms.
Specific examples of a “substituted or unsubstituted arylthio group” mentioned herein include a group represented by —S(G1), G1 being the “substituted or unsubstituted aryl group” in the specific example group G1. An “unsubstituted arylthio group” has, unless otherwise specified herein, 6 to 50, preferably 6 to 30, more preferably 6 to 18 ring carbon atoms.
Specific examples of a “trialkylsilyl group” mentioned herein include a group represented by —Si(G3)(G3)(G3), G3 being the “substituted or unsubstituted alkyl group” in the specific example group G3. The plurality of G3 in —Si(G3)(G3)(G3) are mutually the same or different. Each of the alkyl groups in the “trialkylsilyl group” has, unless otherwise specified herein, 1 to 50, preferably 1 to 20, more preferably 1 to 6 carbon atoms.
Specific examples of a “substituted or unsubstituted aralkyl group” mentioned herein include a group represented by (G3)-(G1), G3 being the “substituted or unsubstituted alkyl group” in the specific example group G3, G1 being the “substituted or unsubstituted aryl group” in the specific example group G1. Accordingly, the “aralkyl group” is a group derived by substituting a hydrogen atom of the “alkyl group” with a substituent in a form of the “aryl group,” which is an example of the “substituted alkyl group.” An “unsubstituted aralkyl group,” which is an “unsubstituted alkyl group” substituted by an “unsubstituted aryl group,” has, unless otherwise specified herein, 7 to 50 carbon atoms, preferably 7 to 30 carbon atoms, more preferably 7 to 18 carbon atoms.
Specific examples of the “substituted or unsubstituted aralkyl group” include a benzyl group, 1-phenylethyl group, 2-phenylethyl group, 1-phenylisopropyl group, 2-phenylisopropyl group, phenyl-t-butyl group, α-naphthylmethyl group, 1-α-naphthylethyl group, 2-α-naphthylethyl group, 1-α-naphthylisopropyl group, 2-α-naphthylisopropyl group, β-naphthylmethyl group, 1-β-naphthylethyl group, 2-β-naphthylethyl group, 1-β-naphthylisopropyl group, and 2-β-naphthylisopropyl group.
Preferable examples of the substituted or unsubstituted aryl group mentioned herein include, unless otherwise specified herein, a phenyl group, p-biphenyl group, m-biphenyl group, o-biphenyl group, p-terphenyl-4-yl group, p-terphenyl-3-yl group, p-terphenyl-2-yl group, m-terphenyl-4-yl group, m-terphenyl-3-yl group, m-terphenyl-2-yl group, o-terphenyl-4-yl group, o-terphenyl-3-yl group, o-terphenyl-2-yl group, 1-naphthyl group, 2-naphthyl group, anthryl group, phenanthryl group, pyrenyl group, chrysenyl group, triphenylenyl group, fluorenyl group, 9,9′-spirobifluorenyl group, 9,9-dimethylfluorenyl group, and 9,9-diphenylfluorenyl group.
Preferable examples of the substituted or unsubstituted heterocyclic group mentioned herein include, unless otherwise specified herein, a pyridyl group, pyrimidinyl group, triazinyl group, quinolyl group, isoquinolyl group, quinazolinyl group, benzimidazolyl group, phenanthrolinyl group, carbazolyl group (1-carbazolyl group, 2-carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, or 9-carbazolyl group), benzocarbazolyl group, azacarbazolyl group, diazacarbazolyl group, dibenzofuranyl group, naphthobenzofuranyl group, azadibenzofuranyl group, diazadibenzofuranyl group, dibenzothiophenyl group, naphthobenzothiophenyl group, azadibenzothiophenyl group, diazadibenzothiophenyl group, (9-phenyl)carbazolyl group ((9-phenyl)carbazole-1-yl group, (9-phenyl)carbazole-2-yl group, (9-phenyl)carbazole-3-yl group, or (9-phenyl)carbazole-4-yl group), (9-biphenylyl)carbazolyl group, (9-phenyl)phenylcarbazolyl group, diphenylcarbazole-9-yl group, phenylcarbazole-9-yl group, phenyltriazinyl group, biphenylyltriazinyl group, diphenyltriazinyl group, phenyldibenzofuranyl group, and phenyldibenzothiophenyl group.
The carbazolyl group mentioned herein is, unless otherwise specified herein, specifically a group represented by one of formulae below.
The (9-phenyl)carbazolyl group mentioned herein is, unless otherwise specified herein, specifically a group represented by one of formulae below.
In the formulae (TEMP-Cz1) to (TEMP-Cz9), * represents a bonding position.
The dibenzofuranyl group and dibenzothiophenyl group mentioned herein are, unless otherwise specified herein, each specifically represented by one of formulae below.
In the formulae (TEMP-34) to (TEMP-41), * represents a bonding position.
Preferable examples of the substituted or unsubstituted alkyl group mentioned herein include, unless otherwise specified herein, a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, and t-butyl group.
The “substituted or unsubstituted arylene group” mentioned herein is, unless otherwise specified herein, a divalent group derived by removing one hydrogen atom on an aryl ring of the “substituted or unsubstituted aryl group.” Specific examples of the “substituted or unsubstituted arylene group” (specific example group G12) include a divalent group derived by removing one hydrogen atom on an aryl ring of the “substituted or unsubstituted aryl group” in the specific example group G1.
The “substituted or unsubstituted divalent heterocyclic group” mentioned herein is, unless otherwise specified herein, a divalent group derived by removing one hydrogen atom on a heterocycle of the “substituted or unsubstituted heterocyclic group.” Specific examples of the “substituted or unsubstituted divalent heterocyclic group” (specific example group G13) include a divalent group derived by removing one hydrogen atom on a heterocyclic ring of the “substituted or unsubstituted heterocyclic group” in the specific example group G2.
The “substituted or unsubstituted alkylene group” mentioned herein is, unless otherwise specified herein, a divalent group derived by removing one hydrogen atom on an alkyl chain of the “substituted or unsubstituted alkyl group.” Specific examples of the “substituted or unsubstituted alkylene group” (specific example group G14) include a divalent group derived by removing one hydrogen atom on an alkyl chain of the “substituted or unsubstituted alkyl group” in the specific example group G3.
The substituted or unsubstituted arylene group mentioned herein is, unless otherwise specified herein, preferably any one of groups represented by formulae (TEMP-42) to (TEMP-68) below.
In the formulae (TEMP-42) to (TEMP-52), Q1 to Q10 are each independently a hydrogen atom or a substituent.
In the formulae (TEMP-42) to (TEMP-52), * represents a bonding position.
In the formulae (TEMP-53) to (TEMP-62), Q1 to Q10 are each independently a hydrogen atom or a substituent.
In the formulae, Q9 and Q10 may be mutually bonded through a single bond to form a ring.
In the formulae (TEMP-53) to (TEMP-62), * represents a bonding position.
In the formulae (TEMP-63) to (TEMP-68), Q1 to Q8 are each independently a hydrogen atom or a substituent.
In the formulae (TEMP-63) to (TEMP-68), * represents a bonding position.
The substituted or unsubstituted divalent heterocyclic group mentioned herein is, unless otherwise specified herein, preferably a group represented by any one of formulae (TEMP-69) to (TEMP-102) below.
In the formulae (TEMP-69) to (TEMP-82), Q1 to Q9 are each independently a hydrogen atom or a substituent.
In the formulae (TEMP-83) to (TEMP-102), Q1 to Q8 are each independently a hydrogen atom or a substituent.
The substituent mentioned herein has been described above.
Instances where “at least one combination of adjacent two or more (of . . . ) are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded” mentioned herein refer to instances where “at least one combination of adjacent two or more (of . . . ) are mutually bonded to form a substituted or unsubstituted monocyclic ring, “at least one combination of adjacent two or more (of . . . ) are mutually bonded to form a substituted or unsubstituted fused ring,” and “at least one combination of adjacent two or more (of . . . ) are not mutually bonded.”
Instances where “at least one combination of adjacent two or more (of . . . ) are mutually bonded to form a substituted or unsubstituted monocyclic ring” and “at least one combination of adjacent two or more (of . . . ) are mutually bonded to form a substituted or unsubstituted fused ring” mentioned herein (these instances will be sometimes collectively referred to as an instance of “bonded to form a ring” hereinafter) will be described below. An anthracene compound having a basic skeleton in a form of an anthracene ring and represented by a formula (TEMP-103) below will be used as an example for the description.
For instance, when “at least one combination of adjacent two or more of R921 to R930 are mutually bonded to form a ring,” the combination of adjacent ones of R921 to R930 (i.e. the combination at issue) is a combination of R921 and R922, a combination of R922 and R923, a combination of R923 and R924, a combination of R924 and R930, a combination of R930 and R925, a combination of R925 and R926, a combination of R926 and R927, a combination of R927 and R928, a combination of R928 and R929, or a combination of R929 and R921.
The term “at least one combination” means that two or more of the above combinations of adjacent two or more of R921 to R930 may simultaneously form rings. For instance, when R921 and R922 are mutually bonded to form a ring QA and R925 and R926 are simultaneously mutually bonded to form a ring QB, the anthracene compound represented by the formula (TEMP-103) is represented by a formula (TEMP-104) below.
The instance where the “combination of adjacent two or more” form a ring means not only an instance where the “two” adjacent components are bonded but also an instance where adjacent “three or more” are bonded. For instance, R921 and R922 are mutually bonded to form a ring QA and R922 and R923 are mutually bonded to form a ring QC, and mutually adjacent three components (R921, R922 and R923) are mutually bonded to form a ring fused to the anthracene basic skeleton. In this case, the anthracene compound represented by the formula (TEMP-103) is represented by a formula (TEMP-105) below. In the formula (TEMP-105) below, the ring QA and the ring QC share R922.
The formed “monocyclic ring” or “fused ring” may be, in terms of the formed ring in itself, a saturated ring or an unsaturated ring. When the “combination of adjacent two” form a “monocyclic ring” or a “fused ring,” the “monocyclic ring” or “fused ring” may be a saturated ring or an unsaturated ring. For instance, the ring QA and the ring QB formed in the formula (TEMP-104) are each independently a “monocyclic ring” or a “fused ring.” Further, the ring QA and the ring QC formed in the formula (TEMP-105) are each a “fused ring.” The ring QA and the ring QC in the formula (TEMP-105) are fused to form a fused ring. When the ring QA in the formula (TMEP-104) is a benzene ring, the ring QA is a monocyclic ring. When the ring QA in the formula (TMEP-104) is a naphthalene ring, the ring QA is a fused ring.
The “unsaturated ring” represents an aromatic hydrocarbon ring or an aromatic heterocycle. The “saturated ring” represents an aliphatic hydrocarbon ring or a non-aromatic heterocycle.
Specific examples of the aromatic hydrocarbon ring include a ring formed by terminating a bond of a group in the specific example of the specific example group G1 with a hydrogen atom.
Specific examples of the aromatic heterocycle include a ring formed by terminating a bond of an aromatic heterocyclic group in the specific example of the specific example group G2 with a hydrogen atom.
Specific examples of the aliphatic hydrocarbon ring include a ring formed by terminating a bond of a group in the specific example of the specific example group G6 with a hydrogen atom.
The phrase “to form a ring” herein means that a ring is formed only by a plurality of atoms of a basic skeleton, or by a combination of a plurality of atoms of the basic skeleton and one or more optional atoms. For instance, the ring QA formed by mutually bonding R921 and R922 shown in the formula (TEMP-104) is a ring formed by a carbon atom of the anthracene skeleton bonded to R921, a carbon atom of the anthracene skeleton bonded to R922, and one or more optional atoms. Specifically, when the ring QA is a monocyclic unsaturated ring formed by R921 and R922, the ring formed by a carbon atom of the anthracene skeleton bonded to R921, a carbon atom of the anthracene skeleton bonded to R922, and four carbon atoms is a benzene ring.
The “optional atom” is, unless otherwise specified herein, preferably at least one atom selected from the group consisting of a carbon atom, nitrogen atom, oxygen atom, and sulfur atom. A bond of the optional atom (e.g. a carbon atom and a nitrogen atom) not forming a ring may be terminated by a hydrogen atom or the like or may be substituted by an “optional substituent” described later. When the ring includes an optional element other than carbon atom, the resultant ring is a heterocycle.
The number of “one or more optional atoms” forming the monocyclic ring or fused ring is, unless otherwise specified herein, preferably in a range from 2 to 15, more preferably in a range from 3 to 12, further preferably in a range from 3 to 5.
Unless otherwise specified herein, the ring, which may be a “monocyclic ring” or “fused ring,” is preferably a “monocyclic ring.”
Unless otherwise specified herein, the ring, which may be a “saturated ring” or “unsaturated ring,” is preferably an “unsaturated ring.”
Unless otherwise specified herein, the “monocyclic ring” is preferably a benzene ring.
Unless otherwise specified herein, the “unsaturated ring” is preferably a benzene ring.
When “at least one combination of adjacent two or more” (of . . . ) are “mutually bonded to form a substituted or unsubstituted monocyclic ring” or “mutually bonded to form a substituted or unsubstituted fused ring,” unless otherwise specified herein, at least one combination of adjacent two or more of components are preferably mutually bonded to form a substituted or unsubstituted “unsaturated ring” formed of a plurality of atoms of the basic skeleton, and 1 to 15 atoms of at least one element selected from the group consisting of carbon, nitrogen, oxygen and sulfur.
When the “monocyclic ring” or the “fused ring” has a substituent, the substituent is the substituent described in later-described “optional substituent.” When the “monocyclic ring” or the “fused ring” has a substituent, specific examples of the substituent are the substituents described in the above under the subtitle “Substituent Mentioned Herein.”
When the “saturated ring” or the “unsaturated ring” has a substituent, the substituent is the substituent described in later-described “optional substituent.” When the “monocyclic ring” or the “fused ring” has a substituent, specific examples of the substituent are the substituents described in the above under the subtitle “Substituent Mentioned Herein.”
The above is the description for the instances where “at least one combination of adjacent two or more (of . . . ) are mutually bonded to form a substituted or unsubstituted monocyclic ring” and “at least one combination of adjacent two or more (of . . . ) are mutually bonded to form a substituted or unsubstituted fused ring” mentioned herein (sometimes referred to as an instance of “bonded to form a ring”).
In an exemplary embodiment herein, a substituent for the substituted or unsubstituted group (sometimes referred to as an “optional substituent” hereinafter) is, for instance, a group selected from the group consisting of an unsubstituted alkyl group having 1 to 50 carbon atoms, an unsubstituted alkenyl group having 2 to 50 carbon atoms, an unsubstituted alkynyl group having 2 to 50 carbon atoms, an unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, —Si(R901)(R902)(R903), —O—(R904), —S—(R905), —N(R906)(R907), a halogen atom, a cyano group, a nitro group, an unsubstituted aryl group having 6 to 50 ring carbon atoms, and an unsubstituted heterocyclic group having 5 to 50 ring atoms;
R901 to R907 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
when two or more R901 are present, the two or more R901 are mutually the same or different;
when two or more R902 are present, the two or more R902 are mutually the same or different;
when two or more R903 are present, the two or more R903 are mutually the same or different;
when two or more R904 are present, the two or more R904 are mutually the same or different;
when two or more R905 are present, the two or more R905 are mutually the same or different;
when two or more R906 are present, the two or more R906 are mutually the same or different; and
when two or more R907 are present, the two or more R907 are mutually the same or different.
In an exemplary embodiment, a substituent for the substituted or unsubstituted group is selected from the group consisting of an alkyl group having 1 to 50 carbon atoms, an aryl group having 6 to 50 ring carbon atoms, and a heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, a substituent for the substituted or unsubstituted group is selected from the group consisting of an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 ring carbon atoms, and a heterocyclic group having 5 to 18 ring atoms.
Specific examples of the above optional substituent are the same as the specific examples of the substituent described in the above under the subtitle “Substituent Mentioned Herein.”
Unless otherwise specified herein, adjacent ones of the optional substituents may form a “saturated ring” or an “unsaturated ring,” preferably a substituted or unsubstituted saturated five-membered ring, a substituted or unsubstituted saturated six-membered ring, a substituted or unsubstituted unsaturated five-membered ring, or a substituted or unsubstituted unsaturated six-membered ring, more preferably a benzene ring.
Unless otherwise specified herein, the optional substituent may further include a substituent. Examples of the substituent for the optional substituent are the same as the examples of the optional substituent.
Herein, numerical ranges represented by “AA to BB” represent a range whose lower limit is the value (AA) recited before “to” and whose upper limit is the value (BB) recited after “to.”
Herein, a numerical formula represented by “A≥B” means that the value A is equal to the value B, or the value A is larger than the value B.
Herein, a numerical formula represented by “A≤B” means that the value A is equal to the value B, or the value A is smaller than the value B.
An organic electroluminescence device according to a first exemplary embodiment includes: an anode; a cathode; two or more emitting units provided between the anode and the cathode; one or more charge generating units provided between the two or more emitting units; a first organic layer provided between the anode and an anode side emitting unit, the anode side emitting unit being one closer to the anode of the two or more emitting units; and a second organic layer provided between the first organic layer and the anode, in which the anode side emitting unit includes a first emitting layer containing a first host material, the first emitting layer is provided close to the anode in the anode side emitting unit, the first organic layer and the first emitting layer are in direct contact with each other, the first organic layer and the second organic layer are in direct contact with each other, the second organic layer and the anode are in direct contact with each other, the first organic layer has a film thickness of 40 nm or less, the first organic layer contains a first organic material, and a difference between an ionization potential Ip(H1) of the first host material and an ionization potential Ip(EBL) of the first organic material satisfies a relationship of a numerical formula (Numerical Formula A1) below.
Ip(H1)−Ip(EBL)≤0.4 eV (Numerical Formula A1)
Herein, an organic electroluminescence device including two or more emitting units provided between an anode and a cathode is referred to as a tandem organic electroluminescence device (tandem organic EL device).
In the tandem organic EL device, when three organic layers, such as a hole injecting layer, a hole transporting layer and an electron blocking layer, are provided in this order from the anode between the anode and the emitting layer of the anode side emitting unit, the device performance (e.g., a luminous efficiency or lifetime) may be decreased when the device is driven at a low current density. In layering the hole injecting layer, the hole transporting layer and the electron blocking layer, when the electron blocking layer in direct contact with the emitting layer has a small film thickness to prevent an increase in drive voltage, a compound contained in the emitting layer of the emitting unit is easily affected by an energy level of a compound contained in the hole transporting layer. This presumably decreases the device performance when the device is driven at a low current density.
In contrast, in the organic EL device according to the exemplary embodiment, two layers that are the first organic layer and the second organic layer are provided between the first emitting layer of the anode side emitting unit and the anode, the film thickness of the first organic layer is 40 nm or less, and the first organic layer contains the first organic material satisfying the relationship of the numerical formula (Numerical Formula A1). This arrangement can prevent the device performance (e.g., a luminous efficiency or lifetime) from decreasing when the device is driven at a low current density.
In the organic EL device according to the exemplary embodiment, the difference “Ip(H1)−Ip(EBL)” between the ionization potential Ip(H1) of the first host material and the ionization potential Ip(EBL) of the first organic material preferably satisfies a relationship of a numerical formula (Numerical Formula A2) below, more preferably satisfies a relationship of a numerical formula (Numerical Formula A3) below.
−0.1 eV≤Ip(H1)−Ip(EBL)≤0.4 eV (Numerical Formula A2)
−0.1 eV≤Ip(H1)−Ip(EBL)≤0.35 eV (Numerical Formula A3)
With the difference “Ip(H1)-Ip(EBL)” in ionization potential being 0.4 eV or less, holes can be abundantly injected into the first emitting layer from the first organic layer.
Herein, the ionization potential is measured using a photoelectron spectroscope under atmosphere. Specifically, the ionization potential is measurable according to the method described in Examples.
In the organic EL device according to the exemplary embodiment, the first organic layer and the second organic layer are provided between the anode side emitting unit and the anode. In the organic EL device according to the exemplary embodiment, the first organic layer is in direct contact with the first emitting layer of the anode side emitting unit, the first organic layer is in direct contact with the second organic layer, and the second organic layer is in direct contact with the anode. In the organic EL device according to the exemplary embodiment, the second organic layer and the first organic layer are provided and layered in this order from the anode.
In the organic EL device according to the exemplary embodiment, the film thickness of the first organic layer is 40 nm or less, preferably 30 nm or less, more preferably 25 nm or less, further preferably 20 nm or less. With the film thickness of the first organic layer being 40 nm or less, the drive voltage can be prevented from increasing.
In the organic EL device according to the exemplary embodiment, the film thickness of the first organic layer is preferably 5 nm or more, more preferably 7 nm or more, further preferably 10 nm or more.
In the organic EL device according to the exemplary embodiment, a singlet energy of the first organic material is preferably 3.1 eV or more, more preferably 3.12 eV or more. With the singlet energy of the first organic material contained in the first organic layer being 3.1 eV or more, the first organic layer can block exciton energy of the first emitting layer in the anode side emitting unit.
In the organic EL device according to the exemplary embodiment, the singlet energy of the first organic material is preferably larger than a singlet energy of the first host material.
In the organic EL device according to the exemplary embodiment, the ionization potential Ip(EBL) of the first organic material is preferably 5.6 eV or more, more preferably 5.65 eV or more. With Ip(EBL) of the first organic material being 5.6 eV or more, a decrease in device performance (e.g., a luminous efficiency or lifetime) at a low current density can be easily prevented.
In the organic EL device according to the exemplary embodiment, the first organic material contained in the first organic layer is preferably a hole transporting material usable for the hole transporting layer, more preferably a monoamine compound having only one substituted amino group in a molecule.
In the organic EL device according to the exemplary embodiment, the first organic material is preferably a compound represented by a formula (31) below.
In the formula (31):
LA, LB and LC are each independently a single bond, or a substituted or unsubstituted arylene group having 6 to 18 ring carbon atoms;
A, B and C are each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, or a group represented by —Si(R391)(R392)(R393);
R391 to R393 are each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms;
when a plurality of R391 are present, the plurality of R391 are mutually the same or different;
when a plurality of R392 are present, the plurality of R392 are mutually the same or different;
when a plurality of R393 are present, the plurality of R393 are mutually the same or different; and
each substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms as A, B and C is independently at least one group selected from the group consisting of groups represented by formulae (31A), (31B), (31C), (31D), (31E) and (31F) below.
In the formulae (31A), (31B), (31C), (31D), (31E) and (31F):
at least one combination of adjacent two or more of R301 to R309 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one combination of adjacent two or more of R310 to R314 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one combination of adjacent two or more of R320 to R324 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R301 to R309, R310, R311 to R314, R320 and R321 to R324 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R381)(R382)(R383), a group represented by —O—(R384), a halogen atom, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
p1 is 3 and a plurality of R310 are mutually the same or different;
p2 is 3 and a plurality of R320 are mutually the same or different; and
* in the formulae (31A), (31B), (31C), (31D), (31E) and (31F) is each independently bonded to one of LA, LB and LC.
In the compound represented by the formula (31), R381, R382, R383 and R384 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
when a plurality of R381 are present, the plurality of R381 are mutually the same or different;
when a plurality of R382 are present, the plurality of R382 are mutually the same or different;
when a plurality of R383 are present, the plurality of R383 are mutually the same or different; and
when a plurality of R384 are present, the plurality of R384 are mutually the same or different.
In the organic EL device according to the exemplary embodiment, it is preferable that each substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms as A, B and C in the formula (31) is independently at least one group selected from the group consisting of groups represented by the formulae (31A), (31E) and (31F).
For instance, in the organic EL device according to the exemplary embodiment, the first organic material is preferably not a compound having two amino groups, such as a compound NPD below.
In the organic EL device according to the exemplary embodiment, the first organic material is preferably a compound represented by a formula (310) below.
In the formula (310):
LC, A, B and C respectively represent the same as those defined in the formula (31);
p3 is 4 and four R330 are mutually the same or different;
at least one combination of adjacent two or more of the four R330 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
p4 is 4 and four R340 are mutually the same or different;
at least one combination of adjacent two or more of the four R340 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R330 and R340 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R381)(R382)(R383), a group represented by —O—(R384), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
R381 to R384 represent the same as those defined in the formula (31).
In the organic EL device according to the exemplary embodiment, it is preferable that two of A, B and C in the formula (31) or (310) are each a group represented by a formula (31 G) below and the two groups represented by the formula (31 G) are mutually the same or different.
In the formula (31 G):
X3 is CR31R32, NR33, an oxygen atom, or a sulfur atom;
when X3 is CR31R32, a combination of R31 and R32 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one combination of adjacent two or more of R350 to R354 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R33, and R350 to R354, R31 and R32 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R381)(R382)(R383), a group represented by —O—(R384), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
p5 is 3 and three R350 are mutually the same or different;
R381 to R384 represent the same as those defined in the formula (31); and
* in the formula (31G) is bonded to LA, LB or LC, bonded to a benzene ring bonded to A in the formula (310), or bonded to a benzene ring bonded to B in the formula (310).
In the organic EL device according to the exemplary embodiment, the first organic material is preferably a compound represented by a formula (311) or (312) below.
In the formulae (311) and (312):
LA, LB, A and B represent the same as those defined in the formula (31);
LC1 is a substituted or unsubstituted arylene group having 6 to 12 ring carbon atoms;
X3 is CR31R32, NR33, an oxygen atom, or a sulfur atom;
when X3 is CR31R32, a combination of R31 and R32 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one combination of adjacent two or more of R360 to R364 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R33, and R360 to R364, R31 and R32 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R381)(R382)(R383), a group represented by —O—(R384), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
p6 is 3 and three R360 are mutually the same or different; and
R381 to R384 represent the same as those defined in the formula (31).
In the organic EL device according to the exemplary embodiment, the first organic material is preferably a compound represented by a formula (313) or (314) below.
In the formulae (313) and (314):
A and B are each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, or a group represented by —Si(R391)(R392)(R393);
R391 to R393 are each independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms;
when a plurality of R391 are present, the plurality of R391 are mutually the same or different;
when a plurality of R392 are present, the plurality of R392 are mutually the same or different;
when a plurality of R393 are present, the plurality of R393 are mutually the same or different;
LC1 is a substituted or unsubstituted arylene group having 6 to 12 ring carbon atoms;
at least one combination of adjacent two or more of R371 to R378 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R371 to R378 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R381)(R382)(R383), a group represented by —O—(R384), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
R381 to R384 represent the same as those defined in the formula (31).
In the organic EL device according to the exemplary embodiment, LC1 is preferably a single bond.
In the organic EL device according to the exemplary embodiment, the first organic material is preferably a compound represented by a formula (315) or (316) below.
In the formulae (315) and (316):
LA, LB, LC, A and B respectively represent the same as those defined in the formula (31);
X3 is CR31R32, NR33, an oxygen atom, or a sulfur atom;
when X3 is CR31R32, a combination of R31 and R32 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one combination of adjacent two or more of R351 to R358 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R33, and R351 to R358, R31 and R32 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R381)(R382)(R383), a group represented by —O—(R384), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
R381 to R384 represent the same as those defined in the formula (31).
In the organic EL device according to the exemplary embodiment, the first organic material is preferably a compound represented by a formula (317) below.
In the formula (317): LA, LB, A and B represent the same as those defined in the formula (31).
In the organic EL device according to the exemplary embodiment, the first organic material is preferably a compound represented by a formula (318) below.
In the formula (318): LA, LB, A and B represent the same as those defined in the formula (31).
In the organic EL device according to the exemplary embodiment, it is also preferable that LA, LB and LC are each independently a single bond or a substituted or unsubstituted arylene group having 6 to 12 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, LC is also preferably a single bond.
In the organic EL device according to the exemplary embodiment, LC is also preferably a substituted or unsubstituted phenylene group.
In the organic EL device according to the exemplary embodiment, it is also preferable that LA, LB and LC are each independently an aromatic hydrocarbon ring group represented by a formula (L1) or (L2) below.
In the formulae (L1) and (L2):
one of two * is bonded to a nitrogen atom shown in the formula (31); and
the other of the two * is bonded to one of A, B and C.
In the organic EL device according to the exemplary embodiment, it is preferable that A in the formulae of the first organic material is a substituted or unsubstituted aryl group having 6 to 12 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, it is preferable that A in the formulae of the first organic material is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted naphthyl group.
In the organic EL device according to the exemplary embodiment, it is preferable that A in the formulae of the first organic material is a phenyl group, a biphenyl group, or a naphthyl group.
In the organic EL device according to the exemplary embodiment, it is preferable that B in the formulae of the first organic material is a substituted or unsubstituted aryl group having 6 to 12 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, it is preferable that B in the formulae of the first organic material is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted naphthyl group.
In the organic EL device according to the exemplary embodiment, it is preferable that B in the formulae of the first organic material is a phenyl group, a biphenyl group, or a naphthyl group.
In the organic EL device according to the exemplary embodiment, it is preferable that A or B in the formulae of the first organic material is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted naphthyl group.
In the organic EL device according to the exemplary embodiment, it is preferable that A and B in the formulae of the first organic material are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted naphthyl group.
In the first organic material, the substituent for the “substituted or unsubstituted” group is preferably not a group represented by —N(RC6)(RC7), in which RC6 and RC7 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the first organic material, all groups described as “substituted or unsubstituted” groups are preferably “unsubstituted” groups.
The first organic material can be manufactured by a known method. The first organic material can also be manufactured based on a known method through a known alternative reaction using a known material(s) tailored for the target compound.
Specific examples of the first organic material include the following compounds. It should however be noted that the invention is not limited to the specific examples of the first organic material.
In the organic EL device according to the exemplary embodiment, a film thickness of the second organic layer is preferably 2 nm or more, more preferably 3 nm or more.
In the organic EL device according to the exemplary embodiment, the film thickness of the second organic layer is preferably 15 nm or less, more preferably 13 nm or less.
In the organic EL device according to the exemplary embodiment, the film thickness of the second organic layer is also preferably smaller than the film thickness of the first organic layer.
In the organic EL device according to the exemplary embodiment, the second organic layer preferably contains a second organic material.
In the organic EL device according to the exemplary embodiment, the first organic material and the second organic material may be mutually different or the same.
In the organic EL device according to the exemplary embodiment, the second organic material is preferably a hole injecting material or a hole transporting material, more preferably an amine derivative, further preferably a monoamine derivative. The second organic material may be a compound represented by the formula (31) or a compound different from the compound represented by the formula (31).
In the organic EL device according to the exemplary embodiment, when the first organic material and the second organic material are mutually different, an ionization potential Ip(HI) of the second organic material is preferably less than 5.6 eV. With Ip(HI) of the second organic material being less than 5.6 eV, the second organic layer is improved in hole injectability. In the organic EL device according to the exemplary embodiment, the second organic layer is preferably a hole injecting layer.
In the organic EL device according to the exemplary embodiment, the second organic layer also preferably contains a third organic material. The third organic material is different from the first organic material and the second organic material. In the organic EL device according to the exemplary embodiment, when the first organic material and the second organic material are mutually different, a content of the third organic material in the second organic layer is preferably 3 mass % or less.
In the organic EL device according to the exemplary embodiment, when the first organic material and the second organic material are mutually different and Ip(HI) of the second organic material is less than 5.6 eV, the second organic layer may or may not contain the third organic material.
In the organic EL device according to the exemplary embodiment, when the second organic layer contains the second organic material and the third organic material and the first organic material and the second organic material are mutually the same or different, the content of the third organic material in the second organic layer can also exceed 3 mass %.
In the organic EL device according to the exemplary embodiment, when the first organic material and the second organic material are mutually the same, it is preferable that the second organic layer contains the second organic material and the third organic material and the content of the third organic material in the second organic layer exceeds 3 mass %.When the first organic material and the second organic material are mutually the same, a content of the third organic material in the second organic layer exceeding 3 mass % improves hole injectability of the second organic layer.
In the organic EL device according to the exemplary embodiment, the third organic material is preferably a compound exhibiting high hole injectability.
In the organic EL device according to the exemplary embodiment, the third organic material is preferably a compound including at least one of a first cyclic structure represented by a formula (P11) below or a second cyclic structure represented by a formula (P12) below.
The first cyclic structure represented by the formula (P11) is fused, in a molecule of the third organic material, to at least one cyclic structure of a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms; and
a structure represented by ═Z10 is represented by a formula (11a), (11b), (11c), (11d), (11e), (11f), (11g), (11h), (11i), (11j), (11k) or (11m) below.
In the formula (11a), (11b), (11c), (11d), (11e), (11f), (11g), (11h), (11i), (11j), (11k) or (11m), R11 to R14 and R1101 to R1110 are each independently a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkyl halide group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the formula (P12), Z1 to Z5 are each independently a nitrogen atom, a carbon atom bonded to R15, or a carbon atom bonded to another atom in the molecule of the third organic material;
at least one of Z1 to Z5 is a carbon atom bonded to another atom in the molecule of the third organic material;
R15 is a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkyl halide group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a carboxy group, a substituted or unsubstituted ester group, a substituted or unsubstituted carbamoyl group, a nitro group, and a substituted or unsubstituted siloxanyl group; and
when a plurality of R15 are present, the plurality of R15 are mutually the same or different.
In the third organic material, R901 to R907 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
when a plurality of R901 are present, the plurality of R901 are mutually the same or different;
when a plurality of R902 are present, the plurality of R902 are mutually the same or different;
when a plurality of R903 are present, the plurality of R903 are mutually the same or different;
when a plurality of R904 are present, the plurality of R904 are mutually the same or different;
when a plurality of R905 are present, the plurality of R905 are mutually the same or different;
when a plurality of R906 are present, the plurality of R906 are mutually the same or different; and
when a plurality of R907 are present, the plurality of R907 are mutually the same or different.
An ester group herein is at least one group selected from the group consisting of an alkyl ester group and an aryl ester group.
An alkyl ester group herein is represented, for instance, by —C(═O)ORE. RE is exemplified by a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms (preferably 1 to 10 carbon atoms).
An aryl ester group herein is represented, for instance, by —C(═O)ORAr. RAr is exemplified by a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms.
A siloxanyl group herein, which is a silicon compound group through an ether bond, is exemplified by a trimethylsiloxanyl group.
A carbamoyl group herein is represented by —CONH2.
A substituted carbamoyl group herein is represented, for instance, by —CONH—ArC or —CONH—RC. ArC is, for instance, at least one group selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms (preferably 6 to 10 ring carbon atoms) and a heterocyclic group having 5 to 50 ring atoms (preferably 5 to 14 ring atoms). ArC may be a group in which a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms is bonded to a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
RC is exemplified by a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms (preferably 1 to 6 carbon atoms).
In the organic EL device according to the exemplary embodiment, the third organic material is preferably a fused compound formed by fusing two or three structures represented by a formula (P13) below to a third cyclic structure selected from a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms and a substituted or unsubstituted heterocycle having 5 to 50 ring atoms.
In the formula (P13):
a is a cyclic structure fused to the third cyclic structure and is represented by the formula (P11);
X11 and X12 are each independently C(R16) or a nitrogen atom and a plurality of R16 are mutually the same or different; and
R16, R17 and R18 are each independently a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkyl halide group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
The third organic material is preferably a compound represented by a formula (P14) or (P15) below.
In the formulae (P14) and (P15):
Pr1 is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms;
a1, a2 and a3 are each independently a cyclic structure represented by the formula (P11);
X13 to X18 each independently represent the same as X11 and X12 in the formula (P13); and
R1141 to R1146 each independently represent the same as R17 and R18 in the formula (P13).
Pr1 in the formulae (P14) and (P15) is preferably a substituted or unsubstituted benzene ring or a substituted or unsubstituted heterocycle having 6 ring atoms.
In the formula (P11), a structure represented by ═X10 is preferably represented by the formula (11a).
That is, the first cyclic structure represented by the formula (P11) is preferably a cyclic structure represented by a formula (11A) below.
A dicyanomethylene group represented by the formula (11a) has a strong electron-withdrawing property and a low molecular symmetry, so that a dipole moment in the molecule increases. Consequently, the compound having a cyclic structure represented by the formula (11 A) has a large electron affinity and is suitably usable as a material for the hole injecting layer.
The third organic material is preferably a compound represented by one of formulae (P141) to (P144) and (P151) below.
In the formulae (P141) to (P144) and (P151): R1141, R1143, R1144 and R1146 are each independently a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, or a cyano group.
The third organic material is also preferably a compound represented by one of formulae (P145) to (P148) and (P152) below.
In the formulae (P145) to (P148) and (P152): Ar141, Ar143, Ar144 and Ar146 are each independently an aromatic hydrocarbon group having 6 to 30 ring carbon atoms and having at least one substituent selected from the group consisting of a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group and a cyano group, or a heterocyclic group having 5 to 30 ring atoms and having at least one substituent selected from the group consisting of a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group and a cyano group.
The third organic material is also preferably a compound represented by one of formulae (P1451), (P1461), (P1471) and (P1481) below.
R1451 to R1460 in the formula (P1451), R1461 to R1470 in the formula (P1461), R1471 to R1480 in the formula (P1471) and R1481 to R1490 in the formula (P1481) are each independently a hydrogen atom, a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, or a cyano group;
at least one of R1451 to R1460 is a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, or a cyano group;
at least one of R1461 to R1470 is a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, or a cyano group;
at least one of R1471 to R1480 is a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, or a cyano group; and
at least one of R1481 to R1490 is a fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, or a cyano group.
The third organic material is also preferably a compound represented by a formula (P121B) below.
In the formula (P121B):
Z1 and Z4 are each independently a nitrogen atom or a carbon atom bonded to R1111, a plurality of Z1 are mutually the same or different, and a plurality of Z4 are mutually the same or different; and
each R1111 independently represents the same as R15 in the formula (P12), and a plurality of R1111 are mutually the same or different.
The third organic material is also preferably a compound represented by a formula (P122D) below.
In the formula (P122D): R1122 to R1125 each independently represent the same as R15 in the formula (P12);
a plurality of R1122 are mutually the same or different;
a plurality of R1123 are mutually the same or different;
a plurality of R1124 are mutually the same or different;
a plurality of R1125 are mutually the same or different; and
Alp1 is a substituted or unsubstituted aliphatic ring having 3 to 6 ring carbon atoms.
The third organic material is also preferably a compound represented by a formula (P122E) below.
In the formula (P122E):
nx is 1, 2, 3, or 4; and
a structure represented by =Zx1, a structure represented by =Zx2 and a structure represented by =Zx3 are each independently represented by a formula (E1), (E2), (E3) or (E4) below.
In the formulae (E1), (E2), (E3) and (E4):
=Zx4 and =Zx5 are each independently selected from oxo (═O) and dicyanomethylidene (═C(CN)2);
R1225 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms;
R1226 is a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
R1221 to R1224 are each independently a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
The formula (122E) in which nx is 1 is represented by a formula (1221E) below. The formula (122E) in which nx is 2 is represented by a formula (1222E) below. The formula (122E) in which nx is 3 is represented by a formula (1223E) below. The formula (122E) in which nx is 4 is represented by a formula (1224E) below.
In the formulae (1221E), (1222E), (1223E) and (1224E):
a structure represented by =Zx1, a structure represented by =Zx2 and a structure represented by =Zx3 are each independently represented by the formula (E1), (E2), (E3) or (E4); and
a plurality of structures represented by =Zx2 are mutually the same or different.
=Zx1, =Zx2 and =Zx3 are each preferably a structure represented by the formula (E3).
The structure represented by the formula (E3) is preferably a structure represented by the formula (11k).
In the formula (11k), R1101 to R1105 are preferably each independently a halogen atom or a cyano group.
In the formula (11k), it is preferable that four of R1101 to R1105 are each independently a halogen atom and one of R1101 to R1105 is a cyano group.
In the formula (11k), it is preferable that R1101, R1102, R1104 and R1105 are each a halogen atom and R1103 is a cyano group.
In R1101 to R1105 of the formula (11k), the halogen atom is preferably a fluorine atom.
The third organic material according to the exemplary embodiment can also be manufactured based on a known method through a known alternative reaction using a known material(s) tailored for the target compound.
Specific examples of the third organic material according to the exemplary embodiment include the following compounds. It should however be noted that the invention is not limited to the specific examples.
The charge generating unit supplies electrons to a layer that is close to the anode with respect to the charge generating unit, and supplies holes to a layer that is close to the cathode with respect to the charge generating unit. The charge generating unit may include a single layer or may include two or more layers. The charge generating unit includes at least a charge generating layer. The charge generating layer is also referred to as an intermediate layer, an intermediate electrode, an intermediate conductive layer, an electron drawing layer, a connection layer, or an intermediate insulative layer. The charge generating layer can be made of a known material. When the charge generating unit includes a single charge generating layer, the charge generating unit may be referred to as a charge generating layer. When the charge generating unit includes a plurality of charge generating layers, the compositions of the plurality of charge generating layers are mutually the same or different.
In the organic EL device according to the exemplary embodiment, it is preferable that at least one of the one or more charge generating units includes an organic layer containing a phenanthroline compound. The phenanthroline compound is a compound having a phenanthroline skeleton.
In the organic EL device according to the exemplary embodiment, it is preferable that at least one of the one or more charge generating units contains an electron donating material.
In the organic EL device according to the exemplary embodiment, it is preferable that at least one of the one or more charge generating units contains a phenanthroline compound and an electron donating material.
The electron donating material is preferably at least one selected from the group consisting of an electron donating metal element, metal compound and metal complex. Specifically, the electron donating material is preferably at least one selected from the group consisting of alkali metal, alkali metal compound, organic metal complex containing alkali metal, alkaline earth metal, alkaline earth metal compound, organic metal complex containing alkaline earth metal, rare earth metal, rare earth metal compound, and organic metal complex containing rare earth metal.
Among these substances, the electron donating material is more preferably at least one selected from the group of alkali metal, alkaline earth metal, rare earth metal element, rare earth metal compound and rare earth metal complex. For instance, in the organic EL device according to the exemplary embodiment, it is preferable that at least one of the charge generating units includes an organic layer containing a phenanthroline compound and at least one metal selected from the group consisting of Li, Yb and Cs.
In the organic EL device according to the exemplary embodiment, it is preferable that the charge generating unit includes at least one N layer and at least one P layer. The N layer is provided closer to the anode than the P layer. In the organic EL device according to the exemplary embodiment, it is preferable that the charge generating unit includes an organic layer containing a phenanthroline compound as the N layer. The charge generating unit may include, as a plurality of N layers, a first N layer provided close to the anode and a second N layer provided close to the cathode with respect to the first N layer. The organic layer containing a phenanthroline compound may be the first N layer or the second N layer.
The N layer preferably contains a π electron-deficient compound and an electron donating material. The π electron-deficient compound is exemplified by a compound capable of coordinating with a metal atom. The π electron-deficient compound is exemplified by a phenanthroline compound, a benzimidazole compound, an azine compound, and quinolinol.
The P layer is a layer containing an acceptor material. The P layer may be a layer doped with the acceptor material (i.e., P-doped layer). The acceptor material also can be selected for use as needed from the “high hole injectable substance” exemplarily listed in the description of the hole injecting layer. The acceptor material also can be selected for use as needed from the above-described third organic material.
In the organic EL device according to the exemplary embodiment, the phenanthroline compound is preferably a compound represented by a formula (20) below and having at least one group represented by a formula (21) below.
In the formula (20):
X21 to X28 are each independently a nitrogen atom, CR21, or a carbon atom bonded to a group represented by the formula (21);
at least one of X21 to X28 is a carbon atom bonded to a group represented by the formula (21);
when a plurality of groups represented by the formula (21) are present, the plurality of groups represented by the formula (21) are mutually the same or different;
at least one combination of adjacent two or more of a plurality of R21 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R21 not forming the substituted or unsubstituted monocyclic ring and not forming the substituted or unsubstituted fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R931, a group represented by —COOR932, a group represented by —S(═O)2R933, a group represented by —B(R934)(R935), a group represented by —P(═O)(R936)(R937), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the formula (21):
Ar2 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
p is 1, 2, 3, 4 or 5;
when two or more Ar2 are present, the two or more Ar2 are mutually the same or different;
L2 is a single bond or a linking group;
L2 as the linking group is a substituted or unsubstituted polyvalent linear, branched or cyclic aliphatic hydrocarbon group having 1 to 50 carbon atoms, a substituted or unsubstituted polyvalent aromatic hydrocarbon group having 6 to 50 ring carbon atoms, a substituted or unsubstituted polyvalent heterocyclic group having 5 to 50 ring atoms, or a polyvalent multiple linking group provided by bonding two or three groups selected from the polyvalent aromatic hydrocarbon ring group and the polyvalent heterocyclic group;
the aromatic hydrocarbon ring group and the heterocyclic group forming L2 as the multiple linking group are mutually the same or different, and adjacent ones thereof are mutually bonded to form a ring, or not mutually bonded;
Ar2 and L2 as the linking group are mutually bonded to form a ring, or not mutually bonded;
L2 as the linking group, and a carbon atom in one of X21 to X28 adjacent to a carbon atom bonded to L2, or R21 in CR21 are mutually bonded to form a ring, or not mutually bonded; and
* in the formula (21) represents a bonding position to a ring represented by the formula (20).
In the phenanthroline compound, R901, R902, R903, R904, R905, R906, R907, R931, R932, R933, R934, R935, R936 and R937 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
when a plurality of R901 are present, the plurality of R901 are mutually the same or different;
when a plurality of R902 are present, the plurality of R902 are mutually the same or different;
when a plurality of R903 are present, the plurality of R903 are mutually the same or different;
when a plurality of R904 are present, the plurality of R904 are mutually the same or different;
when a plurality of R905 are present, the plurality of R905 are mutually the same or different;
when a plurality of R906 are present, the plurality of R906 are mutually the same or different;
when a plurality of R907 are present, the plurality of R907 are mutually the same or different;
when a plurality of R931 are present, the plurality of R931 are mutually the same or different;
when a plurality of R932 are present, the plurality of R932 are mutually the same or different;
when a plurality of R933 are present, the plurality of R933 are mutually the same or different;
when a plurality of R934 are present, the plurality of R934 are mutually the same or different;
when a plurality of R935 are present, the plurality of R935 are mutually the same or different;
when a plurality of R936 are present, the plurality of R936 are mutually the same or different; and
when a plurality of R937 are present, the plurality of R937 are mutually the same or different.
Herein, a group represented by —O—(R904) is a hydroxy group when R904 is a hydrogen atom.
Herein, a group represented by —S—(R905) is a thiol group when R905 is a hydrogen atom.
Herein, a group represented by —S(═O)2R933 is a substituted sulfo group when R933 is a substituent.
Herein, a group represented by —B(R934)(R935) is a substituted boryl group when R934 and R935 are substituents.
Herein, a group represented by —P(═O)(R936)(R937) is a substituted phosphine oxide group when R936 and R937 are substituents, and is an arylphosphoryl group when R936 and R937 are aryl groups.
An “unsubstituted polyvalent linear, branched or cyclic aliphatic hydrocarbon group” mentioned herein has, unless otherwise specified herein, 1 to 50, preferably 1 to 20, more preferably 1 to 6 carbon atoms.
An “unsubstituted polyvalent aromatic hydrocarbon group” mentioned herein has, unless otherwise specified herein, 6 to 50, preferably 6 to 30, more preferably 6 to 18 ring carbon atoms.
An “unsubstituted polyvalent heterocyclic group” mentioned herein has, unless otherwise specified herein, 5 to 50, preferably 5 to 30, more preferably 5 to 18 ring atoms.
A substituted or unsubstituted group derived from a cyclic structure represented by the formula (20) is preferably included as a heterocyclic group having 5 to 50 ring atoms in Ar2 of the formula (21).
X21 and X28 in the formula (20) are also preferably a carbon atom bonded to a group represented by the formula (21).
In the formula (20), it is also preferable that one of X21 and X28 is a carbon atom bonded to a group represented by the formula (21), and the other of X21 and X28 is a carbon atom bonded to a hydrogen atom.
X21 to X28 in the formula (20) are preferably each independently CR21 or a carbon atom bonded to a group represented by the formula (21).
X21 to X28 in the formula (20) not being a carbon atom bonded to a group represented by the formula (21) are preferably CR21. In other words, the compound represented by the formula (20) is preferably a 1,10-phenanthroline derivative.
Ar2 in the formula (21) is also preferably a substituted or unsubstituted fused aromatic hydrocarbon group having 8 to 20 ring carbon atoms.
The fused aromatic hydrocarbon group having 8 to 20 ring carbon atoms is also preferably a group derived from aromatic hydrocarbon selected from the group consisting of, for instance, naphthalene, anthracene, acephenanthrylene, aceanthrylene, benzanthracene, triphenylene, pyrene, chrysene, naphthacene, fluorene, phenanthrene, fluoranthene and benzofluoranthene.
Ar2 in the formula (21) is also preferably a substituted or unsubstituted anthryl group.
Ar2 in the formula (21) is also preferably a substituted or unsubstituted heterocyclic group having 5 to 40 ring carbon atoms.
Ar2 in the formula (21) is also preferably a substituted or unsubstituted group derived from a cyclic structure represented by the formula (20).
Ar2 in the formula (21) is also preferably a group represented by a formula (23) below.
In the formula (23):
X21 to X28 are each independently a nitrogen atom, CR21, a group represented by the formula (21), or a carbon atom bonded to L22 or L23;
L21 is a linking group, and L21 as the linking group is a substituted or unsubstituted trivalent linear, branched or cyclic aliphatic hydrocarbon group having 1 to 50 carbon atoms, a substituted or unsubstituted trivalent aromatic hydrocarbon group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted trivalent heterocyclic group having 5 to 50 ring atoms; and
L22 and L23 are each independently a single bond or a linking group, and L22 and L23 as the linking group are each independently a substituted or unsubstituted divalent linear, branched or cyclic aliphatic hydrocarbon group having 1 to 50 carbon atoms, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms. * in the formula (23) represents a bonding position to L2.
In the formula of the phenanthroline compound:
when a plurality of X21 are present, the plurality of X21 are mutually the same or different;
when a plurality of X22 are present, the plurality of X22 are mutually the same or different;
when a plurality of X23 are present, the plurality of X23 are mutually the same or different;
when a plurality of X24 are present, the plurality of X24 are mutually the same or different;
when a plurality of X25 are present, the plurality of X25 are mutually the same or different;
when a plurality of X26 are present, the plurality of X26 are mutually the same or different;
when a plurality of X27 are present, the plurality of X27 are mutually the same or different; and
when a plurality of X28 are present, the plurality of X28 are mutually the same or different.
X21 to X28 in the formula (23) are preferably each independently a nitrogen atom, CR21, or a carbon atom bonded to L22 or L23, more preferably CR21, or a carbon atom bonded to L22 or L23.
The phenanthroline compound is also preferably a compound represented by a formula (24) below.
In the formula (24):
a plurality of R21 each independently represent the same as R21 in the formula (20);
a plurality of R22 each independently represent the same as R21 in the formula (20);
L2 represents the same as L2 in the formula (21);
p is 1, 2, 3, 4 or 5; and
the plurality of R22 and L2 are bonded to respective ones of carbon atoms at positions 1 to 10 of an anthracene ring.
The phenanthroline compound is also preferably a compound represented by a formula (24A) below.
In the formula (24A):
a plurality of R21 each independently represent the same as R21 in the formula (20);
a plurality of R22 each independently represent the same as R21 in the formula (20); and
L2 represents the same as L2 in the formula (21).
The phenanthroline compound is also preferably a compound represented by a formula (24B) below.
In the formula (24B):
a plurality of R21 each independently represent the same as R21 in the formula (20);
a plurality of R22 each independently represent the same as R21 in the formula (20); and
L2 represents the same as L2 in the formula (21).
The phenanthroline compound is also preferably a compound represented by a formula (25) below.
In the formula (25):
a plurality of R21 each independently represent the same as R21 in the formula (20);
a plurality of R22 each independently represent the same as R21 in the formula (20);
L2 represents the same as L2 in the formula (21);
p is 1, 2, 3, 4 or 5; and
the plurality of R22 and L2 are bonded to respective ones of carbon atoms at positions 2 to 9 of a phenanthroline ring.
The phenanthroline compound is also preferably a compound represented by a formula (25A) below.
In the formula (25A):
a plurality of R21 each independently represent the same as R21 in the formula (20);
a plurality of R22 each independently represent the same as R21 in the formula (20); and
L2 represents the same as L2 in the formula (21).
L2 in the formulae (24), (24A), (24B), (25) and (25A) is also preferably a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms.
The phenanthroline compound is also preferably a compound represented by a formula (25B) below.
In the formula (25B):
a plurality of R21 each independently represent the same as R21 in the formula (20);
a plurality of R22 each independently represent the same as R21 in the formula (20);
L3 is a linking group, and L3 as the linking group is a substituted or unsubstituted polyvalent linear, branched or cyclic aliphatic hydrocarbon group having 1 to 50 carbon atoms, a substituted or unsubstituted polyvalent amino group, a substituted or unsubstituted polyvalent aromatic hydrocarbon ring group having 6 to 50 ring carbon atoms, a substituted or unsubstituted polyvalent heterocyclic group having 5 to 50 ring atoms, or a polyvalent multiple linking group provided by bonding two or three groups selected from the polyvalent aromatic hydrocarbon ring group and the polyvalent heterocyclic group;
the aromatic hydrocarbon ring group and the heterocyclic group forming L3 as the multiple linking group are mutually the same or different, and adjacent ones thereof are mutually bonded to form a ring, or not mutually bonded;
p is 1, 2, 3, 4 or 5; and
the plurality of R22 and L3 are bonded to respective ones of carbon atoms at positions 1 to 10 of a phenanthrene ring.
The phenanthroline compound is also preferably a compound represented by a formula (25C) below.
In the formula (25C):
a plurality of R21 each independently represent the same as R21 in the formula (20);
one of R221 to R230 is a single bond bonded to L3, and R221 to R230 not being the single bond bonded to L3 each independently represent the same as R21 in the formula (20);
L3 is a linking group, and L3 as the linking group represents the same as L3 as the linking group in the formula (25B); and
p is 1, 2, 3, 4 or 5.
The phenanthroline compound is also preferably a compound represented by a formula (25D) below.
In the formula (25D):
a plurality of R21 each independently represent the same as R21 in the formula (20);
one of R221 to R232 is a single bond bonded to L3, and R221 to R232 not being the single bond bonded to L3 each independently represent the same as R21 in the formula (20);
L3 is a linking group, and L3 as the linking group represents the same as L3 as the linking group in the formula (25B); and
p is 1, 2, 3, 4 or 5.
The phenanthroline compound is also preferably a compound represented by a formula (25E) below.
In the formula (25E):
a plurality of R21 each independently represent the same as R21 in the formula (20);
one of R221 to R230 is a single bond bonded to L3, and R221 to R230 not being the single bond bonded to L3 each independently represent the same as R21 in the formula (20);
L3 is a linking group, and L3 as the linking group represents the same as L3 as the linking group in the formula (25B); and
p is 1, 2, 3, 4 or 5.
L3 in the formulae (25B), (25C), (25D) and (25E) is also preferably a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms.
The phenanthroline compound can be manufactured by a known method. The phenanthroline compound also can be manufactured based on a known method through a known alternative reaction using a known material(s) tailored for the target compound.
Specific examples of the phenanthroline compound include the following compounds. It should however be noted that the invention is not limited by the specific examples of the phenanthroline compound.
The organic EL device according to the exemplary embodiment includes two or more emitting units. Each emitting unit may include a single emitting layer or may include a plurality of emitting layers. The emitting unit is provided between the charge generating unit and the anode or between the charge generating unit and the cathode. The charge generating unit is provided between the emitting units. Of the two or more emitting units, the emitting unit provided close to the anode is referred to as an anode side emitting unit.
When the emitting unit includes a fluorescent emitting layer containing a fluorescent compound, the emitting unit is occasionally referred to as a fluorescent emitting unit. When the emitting unit includes a phosphorescent emitting layer containing a phosphorescent compound, the emitting unit is occasionally referred to as a phosphorescent emitting unit.
Examples of the device arrangement of the organic EL device including a plurality of emitting units include (TND1) and (TND2) below.
(TND1) anode/second organic layer/first organic layer/first emitting unit/charge generating unit/second emitting unit/cathode
(TND2) anode/second organic layer/first organic layer/first emitting unit/charge generating unit/second emitting unit/charge generating unit/third emitting unit/cathode
In the device arrangements (TND1) and (TND2), the first emitting unit corresponds to the anode side emitting unit.
In the organic EL device according to the exemplary embodiment, the number of the emitting units and the charge generating units is not limited to the examples of the device arrangements (TND1) and (TND2) shown above.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of less than 500 nm.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of less than 500 nm and at least one emitting unit provided close to the cathode with respect to the anode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of 500 nm or more.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of 490 nm or less.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of 480 nm or less.
An emitting unit that emits light having a maximum peak wavelength of less than 500 nm (for instance, blue light) may be provided as the anode side emitting unit and an emitting unit that emits light having a maximum peak wavelength of 500 nm or more (for instance, at least one of red light or green light) may be provided close to the cathode with respect to the anode side emitting unit. In this case, injectability of electrons from the charge generating unit into the emitting unit is lower than injectability of electrons from the cathode into the emitting unit. Thus, a phosphorescent emitting unit that is shorter in lifetime than a fluorescent emitting unit may be adopted as the emitting unit provided close to the cathode. However, when an anode side emitting unit that emits light having a maximum peak wavelength of less than 500 nm is provided close to the anode, the anode side emitting unit is liable to decrease in luminous efficiency and shorten a lifetime due to the injectability of electrons from the charge generating unit into the emitting unit. Thus, instead of a single emitting layer, layering the first emitting layer and the second emitting layer that satisfy a relationship of a numerical formula (Numerical Formula 3) described later in the anode side emitting unit improves the luminous efficiency and lifetime.
Herein, the blue light emission refers to a light emission in which a maximum peak wavelength of emission spectrum is 430 nm or more and less than 500 nm. Herein, the green light emission refers to a light emission in which a maximum peak wavelength of emission spectrum is in a range from 500 nm to 560 nm. Herein, the red light emission refers to a light emission in which a maximum peak wavelength of emission spectrum is in a range from 600 nm to 660 nm.
In an arrangement of the organic EL device according to the exemplary embodiment, at least one emitting unit provided close to the cathode with respect to the anode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of less than 500 nm.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of 500 nm or more and at least one emitting unit provided close to the cathode with respect to the anode side emitting unit is an emitting unit that emits light having a maximum peakwavelength of less than 500 nm. The emitting unit provided close to the cathode with respect to the anode side emitting unit is occasionally referred to as a cathode side emitting unit. For instance, when the organic EL device according to the exemplary embodiment includes two emitting units, one of the emitting units is an anode side emitting unit and the other is a cathode side emitting unit with the charge generating unit interposed between the anode side emitting unit and the cathode side emitting unit.
In an arrangement of the organic EL device according to the exemplary embodiment, the cathode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of 490 nm or less.
In an arrangement of the organic EL device according to the exemplary embodiment, the cathode side emitting unit is an emitting unit that emits light having a maximum peak wavelength of 480 nm or less.
An emitting unit that emits light having a maximum peak wavelength of 500 nm or more (for instance, at least one of red light or green light) may be provided as the anode side emitting unit and an emitting unit that emits light having a maximum peak wavelength of less than 500 nm (for instance, blue light) may be provided close to the cathode with respect to the anode side emitting unit. This arrangement allows the emitting unit that emits light having a maximum peak wavelength of less than 500 nm to be positioned apart from the anode, easily improving the light extraction efficiency. However, since injectability of holes from the charge generating unit into the emitting unit is lower than injectability of holes from the anode into the emitting unit, the emitting unit that emits light having a maximum peak wavelength of less than 500 nm may have a shorter lifetime. Thus, instead of a single emitting layer, layering the first emitting layer and the second emitting layer that satisfy the relationship of the numerical formula (Numerical Formula 3) described later in the emitting unit provided close to the cathode improves the lifetime.
In the organic EL device according to the exemplary embodiment, all the emitting units may be each an emitting unit that emits light having a maximum peak wavelength of less than 500 nm.
The position of the emitting unit that emits light having a maximum peak wavelength of less than 500 nm (for instance, blue light) may be determined according to a demand for device design or the like. Thus, a preferable composition of the emitting layer in the emitting unit can be appropriately adopted in light of the position thereof.
In the organic EL device according to the exemplary embodiment, the emitting unit may consist of the emitting layer, or may include one or more organic layers in addition to the emitting layer. In the organic EL device according to the exemplary embodiment, the organic layer that may be included in the emitting unit is, for instance, at least one layer selected from the group consisting of an emitting layer, a hole injecting layer, a hole transporting layer, an electron injecting layer, an electron transporting layer, a hole blocking layer, and an electron blocking layer.
In the organic EL device according to the exemplary embodiment, a zone provided close to the anode with respect to the emitting layer of the emitting unit is occasionally referred to as a hole transporting zone. The hole transporting zone may be provided by a single layer or a plurality of layers. The layer forming the hole transporting zone is, for instance, at least one layer selected from the group consisting of a hole injecting layer, a hole transporting layer and an electron blocking layer.
In the organic EL device according to the exemplary embodiment, a zone provided close to the cathode with respect to the emitting layer of the emitting unit is occasionally referred to as an electron transporting zone. The electron transporting zone may be provided by a single layer or a plurality of layers. The layer forming the electron transporting zone is, for instance, at least one layer selected from the group consisting of an electron injecting layer, an electron transporting layer and a hole blocking layer.
In the organic EL device according to the exemplary embodiment, the anode side emitting unit includes the first emitting layer containing the first host material. The first emitting layer is provided close to the anode in the anode side emitting unit. The first organic layer and the second organic layer are provided close to the anode with respect to the first emitting layer. The first emitting layer is in direct contact with the first organic layer.
In the organic EL device according to the exemplary embodiment, the anode side emitting unit may be a fluorescent emitting unit or a phosphorescent emitting unit.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first emitting layer in the anode side emitting unit contains a first emitting compound that emits light having a maximum peak wavelength of less than 500 nm.
In the organic EL device according to the exemplary embodiment, it is also preferable that the anode side emitting unit is a fluorescent emitting unit and the first emitting layer contains a first emitting compound that emits light having a maximum peak wavelength of less than 500 nm.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first emitting layer in the anode side emitting unit contains an emitting compound that emits light having a maximum peak wavelength of 500 nm or more.
In the organic EL device according to the exemplary embodiment, it is also preferable that the anode side emitting unit is a phosphorescent emitting unit and the first emitting layer contains an emitting compound that emits light having a maximum peak wavelength of 500 nm or more.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit includes only the first emitting layer as the emitting layer.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit includes a plurality of emitting layers. The anode side emitting unit of the organic EL device according to the exemplary embodiment may be a layered emitting unit in which a plurality of emitting layers are layered.
In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit includes the first emitting layer and the second emitting layer as the emitting layers. The anode side emitting unit of the organic EL device according to the exemplary embodiment may be a layered emitting unit in which two emitting layers, specifically the first emitting layer and the second emitting layer are layered.
In the organic EL device according to the exemplary embodiment, it is preferable that the second emitting layer is provided between the first emitting layer and the charge generating unit.
In the organic EL device according to the exemplary embodiment, it is preferable that the second emitting layer contains a second host material and a second emitting compound that emits light having a maximum peak wavelength of less than 500 nm.
In the organic EL device according to the exemplary embodiment, it is preferable that the first host material and the second host material are mutually different.
In the organic EL device according to the exemplary embodiment, it is preferable that a triplet energy T1(H1) of the first host material and a triplet energy T1(H2) of the second host material satisfy a relationship of a numerical formula (Numerical Formula 3) below.
T
1(H1)>T1(H2) (Numerical Formula 3)
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes the first emitting layer and the second emitting layer that satisfy the relationship of the numerical formula (Numerical Formula 3), the luminous efficiency of the organic EL device easily improves.
Conventionally, Triplet-Triplet-Annihilation (occasionally referred to as TTA) has been known as a technique for improving the luminous efficiency of the organic electroluminescence device. TTA is a mechanism in which triplet excitons collide with one another to generate singlet excitons. It should be noted that the TTA mechanism is occasionally referred to as a TTF mechanism as described in Patent Literature 8.
The TTF phenomenon will be described. Holes injected from an anode and electrons injected from a cathode are recombined in an emitting layer to generate excitons. As for the spin state, as is conventionally known, singlet excitons account for 25% and triplet excitons account for 75%.In a conventionally known fluorescent device, light is emitted when singlet excitons of 25% are relaxed to the ground state. The remaining triplet excitons of 75% are returned to the ground state without emitting light through a thermal deactivation process. Accordingly, the theoretical limit value of the internal quantum efficiency of a conventional fluorescent device is believed to be 25%.
The behavior of triplet excitons generated within an organic substance has been theoretically examined. According to S. M. Bachilo et al. (J. Phys. Chem. A, 104, 7711 (2000)), assuming that high-order excitons such as quintet excitons are quickly returned to triplet excitons, triplet excitons (hereinafter abbreviated as 3A*) collide with one another with an increase in the density thereof, whereby a reaction shown by the following formula occurs. In the formula, 1A represents the ground state and 1A* represents the lowest singlet excitons.
3
A*+
3
A*→(4/9)1A+(1/9)1A*+(13/9)3A*
In other words, 53A*→41A+1A* is satisfied, and it is expected that, among triplet excitons initially generated, which account for 75%, one fifth thereof (i.e., 20%) is changed to singlet excitons. Accordingly, the amount of singlet excitons which contribute to emission is 40%, which is a value obtained by adding 15% (75%×(1/5)=15%) to 25%, which is the amount ratio of initially generated singlet excitons. At this time, a ratio of luminous intensity derived from TTF (TTF ratio) relative to the total luminous intensity is 15/40, i.e., 37.5%.Assuming that singlet excitons are generated by collision of initially generated triplet excitons accounting for 75% (i.e., one siglet exciton is generated from two triplet excitons), a significantly high internal quantum efficiency of 62.5% is obtained, which is a value obtained by adding 37.5% (75%×(1/2)=37.5%) to 25% (the amount ratio of initially generated singlet excitons). At this time, the TTF ratio is 37.5/62.5=60%.
In the organic electroluminescence device according to the exemplary embodiment, it is considered that triplet excitons generated by recombination of holes and electrons in the first emitting layer of the anode side emitting unit and present on an interface between the first emitting layer and organic layer(s) in direct contact therewith are not likely to be quenched even under the presence of excessive carriers on the interface between the first emitting layer and the organic layer(s). For instance, the presence of a recombination region locally on an interface between the first emitting layer and a hole transporting layer or an electron blocking layer is considered to cause quenching by excessive electrons. Meanwhile, the presence of a recombination region locally on an interface between the first emitting layer and an electron transporting layer or a hole blocking layer is considered to cause quenching by excessive holes.
In an arrangement of the organic electroluminescence device according to the exemplary embodiment, the anode side emitting unit including at least two emitting layers (i.e., the first emitting layer and the second emitting layer) satisfying a predetermined relationship is provided. The triplet energy T1(H1) of the first host material in the first emitting layer and the triplet energy T1(H2) of the second host material in the second emitting layer satisfy the relationship represented by the numerical formula (Numerical Formula 3).
By including the anode side emitting unit that includes the first emitting layer and the second emitting layer so as to satisfy the numerical formula (Numerical Formula 3), triplet excitons generated in the first emitting layer can transfer to the second emitting layer without being quenched by excessive carriers and be inhibited from back-transferring from the second emitting layer to the first emitting layer. Consequently, the second emitting layer exhibits the TTF mechanism to efficiently generate singlet excitons, thereby improving luminous efficiency.
Accordingly, the anode side emitting unit of the organic electroluminescence device includes, as different regions, the first emitting layer mainly generating triplet excitons and the second emitting layer mainly exhibiting the TTF mechanism using triplet excitons having transferred from the first emitting layer, and a difference in triplet energy is provided by using a compound having a smaller triplet energy than that of the first host material in the first emitting layer as the second host material in the second emitting layer, thereby improving the luminous efficiency.
In the organic EL device according to the exemplary embodiment, it is preferable that the triplet energy T1(H1) of the first host material and the triplet energy T1(H2) of the second host material satisfy a relationship of a numerical formula (Numerical Formula 5) below.
T
1(H1)−T1(H2)>0.03 eV (Numerical Formula 5)
In the organic EL device according to the exemplary embodiment, the cathode side emitting unit may be a fluorescent emitting unit or a phosphorescent emitting unit.
In the organic EL device according to the exemplary embodiment, the cathode side emitting unit may include a single emitting layer or may include a plurality of emitting layers in a similar manner to the anode side emitting unit. The cathode side emitting unit of the organic EL device according to the exemplary embodiment may be a layered emitting unit in which a plurality of emitting layers are layered.
In the organic EL device according to the exemplary embodiment, the cathode side emitting unit may include the first emitting layer similar to that in the anode side emitting unit, or may include an emitting layer different from the first emitting layer.
In the organic EL device according to the exemplary embodiment, the cathode side emitting unit may include the second emitting layer similar to that in the anode side emitting unit, or may include an emitting layer different from the second emitting layer.
The cathode side emitting unit of the organic EL device according to the exemplary embodiment may be a layered emitting unit in which two emitting layers, specifically the first emitting layer and the second emitting layer are layered.
In the organic EL device according to the exemplary embodiment, it is preferable that the first emitting layer and the second emitting layer are provided in this order in the cathode side emitting unit.
In the organic EL device according to the exemplary embodiment, it is preferable that the cathode side emitting unit includes the first emitting layer and the second emitting layer that are similar to those in the anode side emitting unit and the first emitting layer and the second emitting layer in the cathode side emitting unit satisfy the relationship of Numerical Formula (3).
In the organic EL device according to the exemplary embodiment, when the cathode side emitting unit includes the first emitting layer and the second emitting layer that satisfy the relationship of the numerical formula (Numerical Formula 3), the lifetime of the organic EL device is easily extended.
The first emitting layer contains the first host material. The first host material and the second host material contained in the second emitting layer are different compounds.
It is preferable that the first emitting layer contains at least a first emitting compound that emits light having a maximum peak wavelength of less than 500 nm. It is preferable that the first emitting compound is a fluorescent compound that exhibits fluorescence having a maximum peak wavelength of less than 500 nm.
In the organic EL device according to the exemplary embodiment, it is preferable that the first emitting layer contains a third compound that fluoresces as the first emitting compound, and the third compound is a compound that emits light having a maximum peak wavelength in a range from 430 nm to 480 nm.
A measurement method of the maximum peak wavelength of a fluorescent compound is as follows. A toluene solution of a measurement target compound at a concentration ranging from 10−6 mol/L to 10−5 mol/L is prepared and put in a quartz cell. An emission spectrum (ordinate axis: emission intensity, abscissa axis: wavelength) of the thus-obtained sample is measured at a normal temperature (300K). The emission spectrum can be measured using a spectrophotometer (machine name: F-7000) manufactured by Hitachi High-Tech Science Corporation. It should be noted that the machine for measuring the emission spectrum is not limited to the machine used herein.
A peak wavelength of the emission spectrum exhibiting the maximum luminous intensity is defined as the maximum emission peak wavelength. Herein, the maximum peak wavelength of fluorescence is sometimes referred to as the maximum fluorescence peak wavelength (FL-peak).
In the organic EL device according to the exemplary embodiment, the first emitting compound is preferably a compound containing no azine ring structure in a molecule thereof.
In the organic EL device according to the exemplary embodiment, the first emitting compound is preferably not a boron-containing complex, more preferably not a complex.
In the organic EL device according to the exemplary embodiment, the first emitting layer preferably does not contain a metal complex. Moreover, in the organic EL device according to the exemplary embodiment, the first emitting layer also preferably does not contain a boron-containing complex.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit is a fluorescent emitting unit, the first emitting layer preferably does not contain a phosphorescent material (dopant material).
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit is a fluorescent emitting unit, the first emitting layer preferably does not contain a heavy metal complex and a phosphorescent rare earth metal complex. Examples of the heavy metal complex herein include iridium complex, osmium complex, and platinum complex.
In an emission spectrum of the first emitting compound, where a peak exhibiting a maximum luminous intensity is defined as a maximum peak and a height of the maximum peak is defined as 1, heights of other peaks appearing in the emission spectrum are preferably less than 0.6. It should be noted that the peaks in the emission spectrum are defined as local maximum values.
Moreover, in the emission spectrum of the first emitting compound, the number of peaks is preferably less than three.
In the organic EL device according to the exemplary embodiment, a singlet energy S1(H1) of the first host material and a singlet energy S1(D1) of the first emitting compound preferably satisfy a relationship of a numerical formula (Numerical Formula 20) below.
S
1(H1)>S1(D1) (Numerical Formula 20)
The singlet energy S1 means an energy difference between the lowest singlet state and the ground state.
When the first host material and the first emitting compound satisfy the relationship of the numerical formula (Numerical Formula 20), singlet excitons generated on the first host material easily energy-transfer from the first host material to the first emitting compound, thereby contributing to fluorescence of the first emitting compound.
In the organic EL device according to the exemplary embodiment, a triplet energy T1(H1) of the first host material and a triplet energy T1(D1) of the first emitting compound preferably satisfy a relationship of a numerical formula (Numerical Formula 20A) below.
T
1(D1)>T1(H1) (Numerical Formula 20A)
When the first host material and the first emitting compound satisfy the relationship of the numerical formula (Numerical Formula 20A), triplet excitons generated in the first emitting layer are transferred not onto the first emitting compound having higher triplet energy but onto the first host material, thereby being easily transferred to the second emitting layer.
The organic EL device according to the exemplary embodiment preferably satisfies a relationship of a numerical formula (Numerical Formula 20B) below.
T
1(D1)>T1(H1)>T1(H2) (Numerical Formula 20B)
A method of measuring a singlet energy S1 with use of a solution (occasionally referred to as a solution method) is exemplified by a method below.
A toluene solution of a measurement target compound at a concentration ranging from 10−5 mol/L to 10−4 mol/L is prepared and put in a quartz cell. An absorption spectrum (ordinate axis: absorption intensity, abscissa axis: wavelength) of the thus-obtained sample is measured at a normal temperature (300K). A tangent was drawn to the fall of the absorption spectrum close to the long-wavelength region, and a wavelength value λedge (nm) at an intersection of the tangent and the abscissa axis was assigned to a conversion equation (F2) below to calculate the singlet energy.
S
1 [eV]=1239.85/λedge Conversion Equation (F2):
Any device for measuring absorption spectrum is usable. For instance, a spectrophotometer (U3310 manufactured by Hitachi, Ltd.) is usable.
The tangent to the fall of the absorption spectrum close to the long-wavelength region is drawn as follows. While moving on a curve of the absorption spectrum from the local maximum value closest to the long-wavelength region, among the local maximum values of the absorption spectrum, in a long-wavelength direction, a tangent at each point on the curve is checked. An inclination of the tangent is decreased and increased in a repeated manner as the curve falls (i.e., a value of the ordinate axis is decreased). A tangent drawn at a point where the inclination of the curve is the local minimum closest to the long-wavelength region (except when absorbance is 0.1 or less) is defined as the tangent to the fall of the absorption spectrum close to the long-wavelength region.
The local maximum absorbance of 0.2 or less is not counted as the above-mentioned local maximum absorbance closest to the long-wavelength region.
A method of measuring triplet energy T1 is exemplified by a method below.
A measurement target compound is dissolved in EPA (diethylether:isopentane:ethanol=5:5:2 in volume ratio) so as to fall within a range from 10−5 mol/L to 10−4 mol/L, and the obtained solution is put in a quartz cell to provide a measurement sample. A phosphorescence spectrum (ordinate axis: phosphorescent luminous intensity, abscissa axis: wavelength) of the measurement sample is measured at a low temperature (77K). A tangent is drawn to the rise of the phosphorescence spectrum close to the short-wavelength region. An energy amount is calculated by a conversion equation (F1) below on a basis of a wavelength value λedge [nm] at an intersection of the tangent and the abscissa axis. The calculated energy amount is defined as triplet energy T1.
T
1 [eV]=1239.85/λedge Conversion Equation (F1):
The tangent to the rise of the phosphorescence spectrum close to the short-wavelength region is drawn as follows. While moving on a curve of the phosphorescence spectrum from the short-wavelength region to the local maximum value closest to the short-wavelength region among the local maximum values of the phosphorescence spectrum, a tangent is checked at each point on the curve toward the long-wavelength of the phosphorescence spectrum. An inclination of the tangent is increased along the rise of the curve (i.e., a value of the ordinate axis is increased).
A tangent drawn at a point of the local maximum inclination (i.e., a tangent at an inflection point) is defined as the tangent to the rise of the phosphorescence spectrum close to the short-wavelength region.
A local maximum point where a peak intensity is 15% or less of the maximum peak intensity of the spectrum is not counted as the above-mentioned local maximum peak intensity closest to the short-wavelength region. The tangent drawn at a point that is closest to the local maximum peak intensity closest to the short-wavelength region and where the inclination of the curve is the local maximum is defined as a tangent to the rise of the phosphorescence spectrum close to the short-wavelength region.
For phosphorescence measurement, a spectrophotofluorometer body F-4500 (manufactured by Hitachi High-Technologies Corporation) is usable. The measurement instrument is not limited to this arrangement. A combination of a cooling unit, a low temperature container, an excitation light source and a light-receiving unit may be used for measurement.
In the organic EL device according to the exemplary embodiment, the first emitting layer preferably contains the first emitting compound at 0.5 mass % or more, more preferably at 1 mass % or more, with respect to a total mass of the first emitting layer.
The first emitting layer preferably contains the first emitting compound at 10 mass % or less, more preferably at 7 mass % or less, further preferably at 5 mass % or less, with respect to the total mass of the first emitting layer.
In the organic EL device according to the exemplary embodiment, the first emitting layer preferably contains the first compound as the first host material at 60 mass % or more, more preferably at 70 mass % or more, further preferably at 80 mass % or more, further more preferably at 90 mass % or more, still further preferably at 95 mass % or more, with respect to the total mass of the first emitting layer.
The first emitting layer preferably contains 99.5 mass % or less of the first host material with respect to the total mass of the first emitting layer.
It should be noted that when the first emitting layer contains the first host material and the first emitting compound, an upper limit of the total of the respective content ratios of the first host material and the first emitting compound is 100 mass %.
It is not excluded that the first emitting layer according to the exemplary embodiment further contains a material(s) other than the first host material and the first emitting compound.
The first emitting layer may include a single type of the first host material or may include two or more types of the first host material. The first emitting layer may include a single type of the first emitting compound or may include two or more types of the first emitting compound.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes only the first emitting layer as the emitting layer, a film thickness of the first emitting layer is preferably 5 nm or more, more preferably 7 nm or more, further preferably 10 nm or more.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes only the first emitting layer as the emitting layer, the film thickness of the first emitting layer is preferably 50 nm or less, more preferably 40 nm or less, further preferably 30 nm or less.
When the cathode side emitting unit includes only the first emitting layer as the emitting layer, a preferable range of the film thickness of the first emitting layer in the cathode side emitting unit is similar to the above range of the film thickness of the first emitting layer in the anode side emitting unit.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes the first emitting layer and the second emitting layer, the film thickness of the first emitting layer is preferably 3 nm or more, more preferably 5 nm or more. When the film thickness of the first emitting layer is 3 nm or more, the film thickness is sufficiently large to cause recombination of holes and electrons in the first emitting layer.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes the first emitting layer and the second emitting layer, the film thickness of the first emitting layer is preferably 15 nm or less, more preferably 10 nm or less. When the film thickness of the first emitting layer is 15 nm or less, the film thickness is sufficiently small to allow transfer of triplet excitons to the second emitting layer.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes the first emitting layer and the second emitting layer, the film thickness of the first emitting layer is more preferably in a range from 3 nm to 15 nm.
When the cathode side emitting unit includes the first emitting layer and the second emitting layer as the emitting layers, a preferable range of the film thickness of the first emitting layer in the cathode side emitting unit is similar to the above range of the film thickness of the first emitting layer in the anode side emitting unit.
The second emitting layer contains the second host material. The second host material and the first host material contained in the first emitting layer are different compounds.
It is preferable that the second emitting layer contains at least a second emitting compound that emits light having a maximum peak wavelength of less than 500 nm. It is preferable that the second emitting compound is a fluorescent compound that exhibits fluorescence having a maximum peak wavelength of less than 500 nm.
The first emitting compound and the second emitting compound are mutually the same or different, preferably the same compound.
A measurement method of the maximum peak wavelength of a compound is as described above.
In the organic EL device according to the exemplary embodiment, it is preferable that the second emitting layer contains a fourth compound that fluoresces as the second emitting compound, and the fourth compound is a compound that emits light having a maximum peak wavelength in a range from 430 nm to 480 nm.
In the organic EL device according to the exemplary embodiment, a half bandwidth of a maximum peak of the second emitting compound is preferably in a range from 1 nm to 20 nm.
In the organic EL device according to the exemplary embodiment, a Stokes shift of the second emitting compound preferably exceeds 7 nm.
When the Stokes shift of the second emitting compound exceeds 7 nm, a reduction in luminous efficiency due to self-absorption is likely to be inhibited.
The self-absorption is a phenomenon where emitted light is absorbed by the same compound to reduce luminous efficiency. The self-absorption is notably observed in a compound having a small Stokes shift (i.e., a large overlap between an absorption spectrum and a fluorescence spectrum). Accordingly, in order to inhibit the self-absorption, it is preferable to use a compound having a large Stokes shift (i.e., a small overlap between the absorption spectrum and the fluorescence spectrum). The Stokes shift can be measured by the following method.
A measurement target compound is dissolved in toluene at a concentration of 2.0×10−5 mol/L to prepare a measurement sample. The measurement sample is put into a quartz cell and is irradiated with continuous light falling within an ultraviolet-to-visible region at a room temperature (300K) to measure an absorption spectrum (ordinate axis: absorbance, abscissa axis: wavelength). A spectrophotometer such as a spectrophotometer U-3900/3900H manufactured by Hitachi High-Tech Science Corporation can be used for the absorption spectrum measurement. Moreover, a measurement target compound is dissolved in toluene at a concentration of 4.9×10−6 mol/L to prepare a measurement sample. The measurement sample is put into a quartz cell and is irradiated with excited light at a room temperature (300K) to measure fluorescence spectrum (ordinate axis: fluorescence intensity, abscissa axis: wavelength). A spectrophotometer can be used for the fluorescence spectrum measurement. For instance, a spectrophotofluorometer F-7000 manufactured by Hitachi High-Tech Science Corporation can be used for the measurement.
A difference between an absorption local maximum wavelength and a fluorescence local maximum wavelength is calculated from the absorption spectrum and the fluorescence spectrum to obtain a Stokes shift (SS). A unit of the Stokes shift (SS) is denoted by nm.
In the organic EL device according to the exemplary embodiment, a triplet energy T1(D2) of the second emitting compound and the triplet energy T1(H2) of the second host material preferably satisfy a relationship of a numerical formula (Numerical Formula 3A) below.
T
1(D2)>T1(H2) (Numerical Formula 3A)
In the organic EL device according to the exemplary embodiment, when the second emitting compound and the second host material satisfy the relationship of the numerical formula (Numerical Formula 3A), in transfer of triplet excitons generated in the first emitting layer to the second emitting layer, the triplet excitons transfer energy thereof not onto the second emitting compound having higher triplet energy but onto molecules of the second host material. In addition, triplet excitons generated by recombination of holes and electrons on the second host material do not transfer to the second emitting compound having higher triplet energy. Triplet excitons generated by recombination on molecules of the second emitting compound quickly energy-transfer to molecules of the second host material.
Triplet excitons in the second host material do not transfer to the second emitting compound but efficiently collide with one another on the second host material to generate singlet excitons by the TTF phenomenon.
In the organic EL device according to the exemplary embodiment, a singlet energy S1(H2) of the second host material and a singlet energy S1(D2) of the second emitting compound preferably satisfy a relationship of a numerical formula (Numerical Formula 4) below.
S
1(H2)>S1(D2) (Numerical Formula 4)
In the organic EL device according to the exemplary embodiment, when the second emitting compound and the second host material satisfy the relationship of the numerical formula (Numerical formula 4), due to the singlet energy of the second emitting compound being smaller than the singlet energy of the second host material, singlet excitons generated by the TTF phenomenon energy-transfer from the second host material to the second emitting compound, thereby contributing to fluorescence of the second emitting compound.
In the organic EL device according to the exemplary embodiment, the second emitting compound is preferably a compound containing no azine ring structure in a molecule thereof.
In the organic EL device according to the exemplary embodiment, the second emitting compound is preferably not a boron-containing complex, more preferably not a complex.
In the organic EL device according to the exemplary embodiment, the second emitting layer preferably does not contain a metal complex. Moreover, in the organic EL device according to the exemplary embodiment, the second emitting layer also preferably does not contain a boron-containing complex.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit is a fluorescent emitting unit, the second emitting layer preferably does not contain a phosphorescent material (dopant material).
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit is a fluorescent emitting unit, the second emitting layer preferably does not contain a heavy metal complex and a phosphorescent rare earth metal complex. Examples of the heavy metal complex herein include iridium complex, osmium complex, and platinum complex.
In the organic EL device according to the exemplary embodiment, the second emitting layer preferably contains the second emitting compound at 0.5 mass % or more, more preferably at 1 mass % or more, with respect to a total mass of the second emitting layer.
The second emitting layer preferably contains the second emitting compound at 10 mass % or less, more preferably at 7 mass % or less, further preferably at 5 mass % or less, with respect to the total mass of the second emitting layer.
The second emitting layer preferably contains a second compound as the second host material at 60 mass % or more, more preferably at 70 mass % or more, further preferably at 80 mass % or more, further more preferably at 90 mass % or more, still further preferably at 95 mass % or more, with respect to the total mass of the second emitting layer.
The second emitting layer preferably contains the second host material at 99 mass % or less with respect to the total mass of the second emitting layer.
When the second emitting layer contains the second host material and the second emitting compound, an upper limit of the total of the respective content ratios of the second host material and the second emitting compound is 100 mass %.
It is not excluded that the second emitting layer according to the exemplary embodiment further contains a material(s) other than the second host material and the second emitting compound.
The second emitting layer may include a single type of the second host material or may include two or more types of the second host material. The second emitting layer may include a single type of the second emitting compound or may include two or more types of the second emitting compound.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes the first emitting layer and the second emitting layer, the film thickness of the second emitting layer is preferably 5 nm or more, more preferably 10 nm or more. When the film thickness of the second emitting layer is 5 nm or more, it is easy to inhibit triplet excitons having transferred from the first emitting layer to the second emitting layer from returning to the first emitting layer. Further, when the film thickness of the second emitting layer is 5 nm or more, triplet excitons can be sufficiently separated from the recombination portion in the first emitting layer.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes the first emitting layer and the second emitting layer, the film thickness of the second emitting layer is preferably 25 nm or less, more preferably 20 nm or less. When the film thickness of the second emitting layer is 25 nm or less, a density of the triplet excitons in the second emitting layer is improved to cause the TTF phenomenon more easily.
In the organic EL device according to the exemplary embodiment, when the anode side emitting unit includes the first emitting layer and the second emitting layer, the film thickness of the second emitting layer is preferably in a range from 5 nm to 25 nm.
When the cathode side emitting unit includes the first emitting layer and the second emitting layer as the emitting layers, a preferable range of the film thickness of the second emitting layer in the cathode side emitting unit is similar to the above range of the film thickness of the second emitting layer in the anode side emitting unit.
In the organic EL device according to the exemplary embodiment, a triplet energy T1(DX) of the first emitting compound or the second emitting compound, the triplet energy T1(H1) of the first host material, and the triplet energy T1(H2) of the second host material preferably satisfy a relationship of a numerical formula (Numerical Formula 10) below.
2.6 eV>T1(DX)>T1(H1)>T1(H2) (Numerical Formula 10)
The triplet energy T1(D1) of the first emitting compound preferably satisfies a relationship of a numerical formula (Numerical Formula 10A) below.
2.6 eV>T1(D1)>T1(H1)>T1(H2) (Numerical Formula 10A)
The triplet energy T1(D2) of the second emitting compound preferably satisfies a relationship of a numerical formula (Numerical Formula 10B) below.
2.6 eV>T1(D2)>T1(H1)>T1(H2) (Numerical Formula 10B)
In the organic EL device according to the exemplary embodiment, the triplet energy T1(DX) of the first emitting compound or the second emitting compound and the triplet energy T1(H1) of the first host material preferably satisfy a relationship of a numerical formula (Numerical Formula 11) below.
0 eV<T1(DX)−T1(H1)<0.6 eV (Numerical Formula 11)
The triplet energy T1(D1) of the first emitting compound preferably satisfies a relationship of a numerical formula (Numerical Formula 11A) below.
0 eV<T1(D1)−T1(H1)<0.6 eV (Numerical Formula 11A)
The triplet energy T1(D2) of the second emitting compound preferably satisfies a relationship of a numerical formula (Numerical Formula 11B) below.
0 eV<T1(D2)−T1(H2)<0.8 eV (Numerical Formula 11B)
In the organic EL device according to the exemplary embodiment, the triplet energy T1(H1) of the first host material preferably satisfies a relationship of a numerical formula (Numerical Formula 12) below.
T
1(H1)>2.0 eV (Numerical Formula 12)
In the organic EL device according to the exemplary embodiment, the triplet energy T1(H1) of the first host material also preferably satisfies a relationship of a numerical formula (Numerical Formula 12A) below, or also preferably satisfies a relationship of a numerical formula (Numerical Formula 12B) below.
T
1(H1)>2.10 eV (Numerical Formula 12A)
T
1(H1)>2.15 eV (Numerical Formula 12B)
In the organic EL device according to the exemplary embodiment, when the triplet energy T1(H1) of the first host material satisfies the relationship of the numerical formula (Numerical Formula 12A) or the numerical formula (Numerical Formula 12B), triplet excitons generated in the first emitting layer are easily transferred to the second emitting layer, and also easily inhibited from back-transferring from the second emitting layer to the first emitting layer. Consequently, singlet excitons are efficiently generated in the second emitting layer, thereby improving luminous efficiency.
In the organic EL device according to the exemplary embodiment, the triplet energy T1(H1) of the first host material also preferably satisfies a relationship of a numerical formula (Numerical Formula 12C) below, or also preferably satisfies a relationship of a numerical formula (Numerical Formula 12D) below.
2.08 eV>T1(H1)>1.87 eV (Numerical Formula 12C)
2.05 eV>T1(H1)>1.90 eV (Numerical Formula 12D)
In the organic EL device according to the exemplary embodiment, when the triplet energy T1(H1) of the first host material satisfies the relationship of the numerical formula (Numerical Formula 12C) or the numerical formula (Numerical Formula 12D), energy of the triplet excitons generated in the first emitting layer is reduced, so that the organic EL device can be expected to have a longer lifetime.
In the organic EL device according to the exemplary embodiment, the triplet energy T1(D1) of the first emitting compound also preferably satisfies a relationship of a numerical formula (Numerical Formula 14A) below, or also preferably satisfies a relationship of a numerical formula (Numerical Formula 14B) below.
2.60 eV>T1(D1) (Numerical Formula 14A)
2.50 eV>T1(D1) (Numerical Formula 14B)
When the first emitting layer contains the first emitting compound that satisfies the relationship of the numerical formula (Numerical Formula 14A) or (Numerical Formula 14B), the organic EL device has a longer lifetime.
In the organic EL device according to the exemplary embodiment, the triplet energy T1(D2) of the second emitting compound also preferably satisfies a relationship of a numerical formula (Numerical Formula 14C) below, or also preferably satisfies a relationship of a numerical formula (Numerical Formula 14D) below.
2.60 eV>T1(D2) (Numerical Formula 14C)
2.50 eV>T1(D2) (Numerical Formula 14D)
When the second emitting layer contains the compound that satisfies the relationship of the numerical formula (Numerical Formula 14C) or (Numerical Formula 14D), the organic EL device has a longer lifetime.
In the organic EL device according to the exemplary embodiment, the triplet energy T1(H2) of the second host material preferably satisfies a relationship of a numerical formula (Numerical Formula 13) below.
T
1(H2)>1.9 eV (Numerical Formula 13)
In the organic EL device according to the exemplary embodiment, when the first emitting layer and the second emitting layer satisfy the relationship of the numerical formula (Numerical Formula 3), it is also preferable that a hole mobility μh(H1) of the first host material and a hole mobility μh(H2) of the second host material satisfy a relationship of a numerical formula (Numerical Formula 31) below. When the first host material and the second host material satisfy the relationship of the numerical formula (Numerical Formula 31), the compound contained in the charge generating unit can be further prevented from deteriorating.
μh(H1)>μh(H2) (Numerical Formula 31)
In the organic EL device according to the exemplary embodiment, when the first emitting layer and the second emitting layer satisfy the relationship of the numerical formula (Numerical Formula 3), it is also preferable that the hole mobility μh(H1) of the first host material, an electron mobility μe(H1) of the first host material, the hole mobility μh(H2) of the second host material, and an electron mobility μe(H2) of the second host material satisfy a relationship of a numerical formula (Numerical Formula 32) below. When the first host material and the second host material satisfy the relationship of the numerical formula (Numerical Formula 32), the compound contained in the charge generating unit can be further prevented from deteriorating.
μe(H1)/μh(H1))<(μe(H2)/μh(H2)) (Numerical Formula 32)
In the organic EL device according to the exemplary embodiment, when the first emitting layer and the second emitting layer satisfy the relationship of the numerical formula (Numerical Formula 3), it is also preferable that the electron mobility μe(H1) of the first host material and the electron mobility μe(H2) of the second host material satisfy a numerical formula (Numerical Formula 33) below. When the first host material and the second host material satisfy the relationship of the numerical formula (Numerical Formula 33), a recombination ability between holes and electrons in the first emitting layer is improved.
μe(H1)<μe(H2) (Numerical Formula 33)
The electron mobility can be measured according to an impedance measurement using a mobility evaluation device manufactured by the following steps. The mobility evaluation device is, for instance, manufactured by the following steps.
A compound Target, which is to be measured for an electron mobility, is vapor-deposited on a glass substrate having an aluminum electrode (anode) so as to cover the aluminum electrode, thereby forming a measurement target layer. A compound ET-A below is vapor-deposited on this measurement target layer to form an electron transporting layer. LiF is vapor-deposited on this formed electron transporting layer to form an electron injecting layer. Metal aluminum (Al) is vapor-deposited on this formed electron injecting layer to form a metal cathode.
An arrangement of the mobility evaluation device above is roughly shown as follows.
Glass/Al(50)/Target(200)/ET-A(10)/LiF(1)/Al(50)
Numerals in parentheses represent a film thickness (nm).
The mobility evaluation device for an electron mobility is set in an impedance measurement device to perform an impedance measurement. In the impedance measurement, a measurement frequency is swept from 1 Hz to 1 MHz. At this time, an alternating current amplitude of 0.1 V and a direct current voltage V are applied to the device. A modulus M is calculated from a measured impedance Z using a relationship of a calculation formula (C1) below.
M=jωZ Calculation formula (C1):
In the calculation formula (C1), j is an imaginary unit whose square is −1 and ω is an angular frequency [rad/s].
In a bode plot in which an imaginary part of the modulus M is represented by an ordinate axis and the frequency [Hz] is represented by an abscissa axis, an electrical time constant τ of the mobility evaluation device is obtained from a frequency fmax showing a peak using a calculation formula (C2) below.
τ=1/(2πfmax) Calculation formula (C2):
π in the calculation formula (C2) is a symbol representing a circumference ratio.
An electron mobility μe is calculated from a relationship of a calculation formula (C3-1) below using τ.
μe=d2/(VT) Calculation formula (C3-1):
d in the calculation formula (C3-1) is a total film thickness of organic thin film(s) forming the device. In a case of the arrangement of the mobility evaluation device for an electron mobility, d=210 [nm] is satisfied.
The hole mobility can be measured according to an impedance measurement using a mobility evaluation device manufactured by the following steps. The mobility evaluation device is, for instance, manufactured by the following steps.
A compound HA-2 below is vapor-deposited on a glass substrate having an ITO transparent electrode (anode) so as to cover the transparent electrode, thereby forming a hole injecting layer. A compound HT-A below is vapor-deposited on this formed hole injecting layer to form a hole transporting layer. Subsequently, a compound Target, which is to be measured for a hole mobility, is vapor-deposited to form a measurement target layer. Metal aluminum (Al) is vapor-deposited on this measurement target layer to form a metal cathode.
An arrangement of the mobility evaluation device above is roughly shown as follows.
ITO(130)/HA-2(5)/HT-A(10)/Target(200)/Al(80)
Numerals in parentheses represent a film thickness (nm).
The mobility evaluation device for a hole mobility is set in an impedance measurement device to perform an impedance measurement. In the impedance measurement, a measurement frequency is swept from 1 Hz to 1 MHz. At this time, an alternating current amplitude of 0.1 V and a direct current voltage V are applied to the device. A modulus M is calculated from a measured impedance Z using the relationship of the calculation formula (C1).
In a bode plot in which an imaginary part of the modulus M is represented by an ordinate axis and the frequency [Hz] is represented by an abscissa axis, an electrical time constant τ of the mobility evaluation device is obtained from a frequency fmax showing a peak using the calculation formula (C2).
A hole mobility μh is calculated from a relationship of a calculation formula (C3-2) below using τ obtained from the calculation formula (C2).
μh=d2/(VT) Calculation formula (C3-2):
d in the calculation formula (C3-2) is a total film thickness of organic thin film(s) forming the device. In a case of the arrangement of the mobility evaluation device for a hole mobility, d=215 [nm] is satisfied.
The electron mobility and the hole mobility herein are each a value obtained in a case where a square root of an electric field intensity meets E1/2=500 [V1/2/cm1/2]. The square root of an electric field intensity, E1/2, can be calculated from a relationship of a calculation formula (C4) below.
E
1/2
=V
1/2
/d
1/2 Calculation formula (C4):
For the impedance measurement, a 1260 type by Solartron Analytical is used as the impedance measurement device, and for a higher accuracy, a 1296 type dielectric constant measurement interface by Solartron Analytical can be used together therewith.
In the organic EL device according to the exemplary embodiment, the triplet energy T1(H1) of the first host material in the first emitting layer and the triplet energy T1(H2) of the second host material in the second emitting layer can also satisfy a relationship of a numerical formula (Numerical Formula 3B) below.
T
1(H1)<T1(H2) (Numerical Formula 3B)
When at least one of the anode side emitting unit or the cathode side emitting unit includes the first emitting layer and the second emitting layer that satisfy the numerical formula (Numerical Formula 3B), triplet excitons generated in the second emitting layer can transfer to the first emitting layer without being quenched by excessive carriers and be inhibited from back-transferring from the first emitting layer to the second emitting layer. Consequently, the first emitting layer exhibits the TTF mechanism to effectively generate singlet excitons, thereby improving the luminous efficiency.
The emitting unit satisfying the relationship of the numerical formula (Numerical Formula 3B) includes, as different regions, the second emitting layer mainly generating triplet excitons and the first emitting layer mainly exhibiting the TTF mechanism using triplet excitons having transferred from the second emitting layer, and a difference in triplet energy is provided by using a compound having a smaller triplet energy than that of the second host material in the second emitting layer as the first host material in the first emitting layer, thereby improving the luminous efficiency.
When at least one of the anode side emitting unit or the cathode side emitting unit includes the first emitting layer and the second emitting layer that satisfy the numerical formula (Numerical Formula 3B), the relationship of the first emitting layer and the second emitting layer that satisfy the relationship of the numerical formula (Numerical Formula 3) can be applied to the arrangement satisfying the relationship of the numerical formula (Numerical Formula 3B) by reversing the relationship of the first emitting layer and the second emitting layer.
In the organic EL device according to the exemplary embodiment, it is preferable that the first emitting layer and the second emitting layer are in direct contact with each other. In the organic EL device according to the exemplary embodiment, the first emitting layer and the second emitting layer may not be in direct contact with each other.
Herein, a layer arrangement in which the first emitting layer and the second emitting layer are in direct contact with each other can include one of embodiments (LS1), (LS2) and (LS3) below.
(LS1) An embodiment in which a region containing both the first host material and the second host material is generated in a process of vapor-depositing the compound of the first emitting layer and vapor-depositing the compound of the second emitting layer, and is present on the interface between the first emitting layer and the second emitting layer.
(LS2) An embodiment in which in a case of containing an emitting compound in the first emitting layer and the second emitting layer, a region containing all of the first host material, the second host material and the emitting compound is generated in a process of vapor-depositing the compound of the first emitting layer and vapor-depositing the compound of the second emitting layer, and is present on the interface between the first emitting layer and the second emitting layer.
(LS3) An embodiment in which in a case of containing an emitting compound in the first emitting layer and the second emitting layer, a region containing the emitting compound, a region containing the first host material or a region containing the second host material is generated in a process of vapor-depositing the compound of the first emitting layer and vapor-depositing the compound of the second emitting layer, and is present on the interface between the first emitting layer and the second emitting layer.
The organic EL device according to the exemplary embodiment may further include a third emitting layer.
It is preferable that the third emitting layer contains a third host material, the first host material, the second host material and the third host material are mutually different, the third emitting layer contains at least a third emitting compound that emits light having a maximum peak wavelength of less than 500 nm, the first emitting compound, the second emitting compound and the third emitting compound are mutually the same or different, and the triplet energy T1(H1) of the first host material and a triplet energy T1(H3) of the third host material satisfy a relationship of a numerical formula (Numerical Formula 1A) below.
T
1(H1)>T1(H3) (Numerical Formula 1A)
When the organic EL device according to the exemplary embodiment includes the third emitting layer, the triplet energy T1(H2) of the second host material and the triplet energy T1(H3) of the third host material preferably satisfy a relationship of a numerical formula (Numerical Formula 1B) below.
T
1(H2)>T1(H3) (Numerical Formula 1B)
When the organic EL device according to the exemplary embodiment contains the third emitting layer, it is preferable that the first emitting layer and the second emitting layer are in direct contact with each other and the second emitting layer and the third emitting layer are in direct contact with each other.
Herein, a layer arrangement in which the second emitting layer and the third emitting layer are in direct contact with each other can include one of embodiments (LS4), (LS5) and (LS6) below.
(LS4) An embodiment in which a region containing both the second host material and the third host material is generated in a process of vapor-depositing the compound of the second emitting layer and vapor-depositing the compound of the third emitting layer, and is present on the interface between the second emitting layer and the third emitting layer.
(LS5) An embodiment in which in a case of containing an emitting compound in the second emitting layer and the third emitting layer, a region containing all of the second host material, the third host material and the emitting compound is generated in a process of vapor-depositing the compound of the second emitting layer and vapor-depositing the compound of the third emitting layer, and is present on the interface between the second emitting layer and the third emitting layer.
(LS6) An embodiment in which in a case of containing an emitting compound in the second emitting layer and the third emitting layer, a region containing the emitting compound, a region containing the second host material or a region containing the third host material is generated in a process of vapor-depositing the compound of the second emitting layer and vapor-depositing the compound of the third emitting layer, and is present on the interface between the second emitting layer and the third emitting layer.
It is also preferable that the layered emitting unit of the organic EL device according to the exemplary embodiment is provided between the organic layers and further includes a layer containing no emitting compound (occasionally referred to as an interposed layer).
When the layered emitting unit of the organic EL device according to the exemplary embodiment includes the layer containing no emitting compound (interposed layer), the layer containing no emitting compound (interposed layer) is preferably disposed between the first emitting layer and the second emitting layer.
The interposed layer preferably does not contain a metal atom.
The interposed layer contains an organic material. The organic material contained in the interposed layer is preferably not an emitting compound.
Examples of the organic material contained in the interposed layer include: 1) a heterocyclic compound such as an oxadiazole derivative, benzimidazole derivative, or phenanthroline derivative; 2) a fused aromatic compound such as a carbazole derivative, anthracene derivative, phenanthrene derivative, pyrene derivative or chrysene derivative; and 3) an aromatic amine compound such as a triarylamine derivative or a fused polycyclic aromatic amine derivative.
The organic material contained in the interposed layer may be one or both of the first host material contained in the first emitting layer and the second host material contained in the second emitting layer.
When the interposed layer contains a plurality of organic materials, the content ratios thereof are each preferably at 10 mass % or more relative to the total mass amount of the interposed layer.
The interposed layer preferably contains the organic material at 60 mass % or more relative to the total mass amount of the interposed layer, more preferably at 70 mass % or more relative to the total mass amount of the interposed layer, further preferably at 80 mass % or more relative to the total mass amount of the interposed layer, further more preferably at 90 mass % or more relative to the total mass amount of the interposed layer, still further preferably at 95 mass % or more, relative to the total mass amount of the interposed layer.
The interposed layer may include a single type of the organic material or may include two or more types of the organic material.
When the interposed layer contains two or more types of the organic material, an upper limit of the total of the respective content ratios of the two or more types of the organic material is 100 mass %.
It is not excluded that the interposed layer according to the exemplary embodiment further contains a material(s) other than the organic material.
The interposed layer may be provided in the form of a single layer or a laminate of two or more layers.
A film thickness of the interposed layer is not particularly limited but each layer in the interposed layer is preferably in a range from 3 nm to 15 nm, more preferably in a range from 5 nm to 10 nm.
Herein, the “host material” refers to, for instance, a material that accounts for “50 mass % or more of the layer.” Accordingly, for instance, the first emitting layer contains 50 mass % or more of the first compound represented by the formula (1) below with respect to a total mass of the first emitting layer. The second emitting layer contains 50 mass % or more of the second compound represented by the formula (2) below with respect to a total mass of the second emitting layer.
In the organic EL device according to the exemplary embodiment, the first host material, the second host material and the third host material are each independently, for instance, a first compound represented by the formula (1), a formula (1X), a formula (12X), a formula (13X), a formula (14X), a formula (15X) or a formula (16X) below, or a second compound represented by the formula (2). Moreover, the first compound also can be used as the first host material and the second host material. In this case, the compound represented by the formula (1), (1X), (12X), (13X), (14X), (15X), or (16X) used as the second host material is sometimes referred to as the second compound for convenience.
In the organic EL device according to the exemplary embodiment, it is preferable that the first host material has a structure of Condition (i) or a structure of Condition (ii) below in a molecule.
Condition (i): a biphenyl structure comprising a first benzene ring and a second benzene ring that are linked to each other with a single bond, the first benzene ring and the second benzene ring in the biphenyl structure being further linked to each other by cross-linking at at least one site other than the single bond,
Condition (ii): a linking structure comprising a benzene ring and a naphthalene ring that are linked to each other with a single bond, the benzene ring and the naphthalene ring in the linking structure being each independently further fused or not fused with a monocyclic ring or fused ring, the benzene ring and the naphthalene ring in the linking structure being further linked to each other by cross-linking at at least one site other than the single bond.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has a structure of Condition (ii) in a molecule.
Since the first host material has the linking structure including such cross-linking, it can be expected to inhibit the deterioration in the chromaticity of the organic EL device.
The first host material in the above case is only required to have a linking structure as the minimum unit in a molecule, the linking structure including a benzene ring and a naphthalene ring linked to each other with a single bond, the linking structure being as represented by a formula (X1) or a formula (X2) below (referred to as a benzene-naphthalene linking structure in some cases). Further, the benzene ring may be fused with a monocyclic ring or fused ring, and the naphthalene ring may be fused with a monocyclic ring or fused ring. For example, also in a case where the first host material has a linking structure including a naphthalene ring and a naphthalene ring linked to each other with a single bond (referred to as a naphthalene-naphthalene linking structure in some cases) and being as represented by a formula (X3), a formula (X4), or a formula (X5) below, the naphthalene-naphthalene linking structure is regarded as including the benzene-naphthalene linking structure since one of the naphthalene rings includes a benzene ring.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has a structure of Condition (ii) in a molecule and the cross-linking includes a double bond. Specifically, the first host material also preferably has a linking structure in which the benzene ring and the naphthalene ring are further linked to each other at any other site than the single bond by a cross-linking structure including a double bond.
Assuming that the benzene ring and the naphthalene ring in the benzene-naphthalene linking structure are further linked to each other at at least one site other than the single bond by crosslinking, for example, a linking structure (fused ring) represented by a formula (X11) below is obtained in a case of the formula (X1), and a linking structure (fused ring) represented by a formula (X31) below is obtained in a case of the formula (X3).
Assuming that the benzene ring and the naphthalene ring in the benzene-naphthalene linking structure are further linked to each other at any other site than the single bond by cross-linking including a double bond, for instance, a linking structure (fused ring) represented by a formula (X12) below is obtained in a case of the formula (X1), a linking structure (fused ring) represented by a formula (X21), a formula (X22) or a formula (X23) below is obtained in a case of the formula (X2), a linking structure (fused ring) represented by a formula (X41) below is obtained in a case of the formula (X4), and a linking structure (fused ring) represented by a formula (X51) below is obtained in a case of the formula (X5).
Assuming that the benzene ring and the naphthalene ring in the benzene-naphthalene linking structure are further linked to each other at at least one site other than the single bond by cross-linking including a hetero atom (e.g., an oxygen atom), for example, a linking structure (fused ring) represented by a formula (X13) below is obtained in a case of the formula (X1).
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has the structure of Condition (i), i.e., has in a molecule, a biphenyl structure including a first benzene ring and a second benzene ring linked to each other with a single bond, and the first benzene ring and the second benzene ring in the biphenyl structure are further linked to each other by cross-linking at at least one site other than the single bond.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has a structure of Condition (i) in a molecule and the first benzene ring and the second benzene ring in the biphenyl structure are further linked by the cross-linking at one site other than the single bond. Since the first host material has the biphenyl structure including such cross-linking, it can be expected to inhibit the deterioration in the chromaticity of the organic EL device.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has a structure of Condition (i) in a molecule and the first benzene ring and the second benzene ring in the biphenyl structure are further linked by the cross-linking at two sites other than the single bond.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has the structure of Condition (i) in a molecule and the cross-linking includes a double bond.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has the structure of Condition (i) in a molecule and the cross-linking includes no double bond.
In the organic EL device according to the exemplary embodiment, it is also preferable that the first host material has a structure of Condition (i) in a molecule, the first benzene ring and the second benzene ring in the biphenyl structure are further linked by the cross-linking at two sites other than the single bond and the cross-linking includes no double bond. Since the first host material has the biphenyl structure including such cross-linking, it can be expected to inhibit the deterioration in the chromaticity of the organic EL device.
For example, assuming that the first benzene ring and the second benzene ring in the biphenyl structure represented by a formula (BP1) below are further linked to each other by cross-linking at at least one site other than the single bond, the biphenyl structure is exemplified by linking structures (fused rings) represented by formulae (BP11) to (BP15) below.
The formula (BP11) represents a linking structure in which the first benzene ring and the second benzene ring are linked to each other at one site other than the single bond by cross-linking including no double bond.
The formula (BP12) represents a linking structure in which the first benzene ring and the second benzene ring are linked to each other at one site other than the single bond by cross-linking including a double bond.
The formula (BP13) represents a linking structure in which the first benzene ring and the second benzene ring are linked to each other at two sites other than the single bond by cross-linking including no double bond.
The formula (BP14) represents a linking structure in which the first benzene ring and the second benzene ring are linked to each other at one of two sites other than the single bond by cross-linking including no double bond while being linked to each other at the other of the two sites other than the single bond by cross-linking including a double bond.
The formula (BP15) represents a linking structure in which the first benzene ring and the second benzene ring are linked to each other at two sites other than the single bond by cross-linking including double bonds.
In the organic EL device according to the exemplary embodiment, the first host material is also preferably the first compound represented by the formula (1) and having at least one group represented by a formula (11) below.
In the formula (1):
R101 to R110 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (11);
at least one of R101 to R110 is a group represented by the formula (11);
when a plurality of groups represented by the formula (11) are present, the plurality of groups represented by the formula (11) are mutually the same or different;
L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar101 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx is 0, 1, 2, 3, 4, or 5; and
when two or more L101 are present, the two or more L101 are mutually the same or different;
when two or more Ar101 are present, the two or more Ar101 are mutually the same or different; and
* in the formula (11) represents a bonding position to a pyrene ring in the formula (1).
In the first compound according to the exemplary embodiment: R901, R902, R903, R904, R905, R906, R907, R801, and R802 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
when a plurality of R901 are present, the plurality of R901 are mutually the same or different;
when a plurality of R902 are present, the plurality of R902 are mutually the same or different;
when a plurality of R903 are present, the plurality of R903 are mutually the same or different;
when a plurality of R904 are present, the plurality of R904 are mutually the same or different;
when a plurality of R905 are present, the plurality of R905 are mutually the same or different;
when a plurality of R906 are present, the plurality of R906 are mutually the same or different;
when a plurality of R907 are present, the plurality of R907 are mutually the same or different;
when a plurality of R801 are present, the plurality of R801 are mutually the same or different; and
when a plurality of R802 are present, the plurality of R802 are mutually the same or different.
In the organic EL device according to the exemplary embodiment, the group represented by the formula (11) is preferably a group represented by a formula (111) below.
In the formula (111):
X1 is CR123R124, an oxygen atom, a sulfur atom, or NR125;
L111 and L112 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
ma is 0, 1, 2, 3, or 4;
mb is 0, 1, 2, 3, or 4;
ma+mb is 0, 1, 2, 3, or 4;
Ar101 represents the same as Ar101 in the formula (11);
R121, R122, R123, R124 and R125 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mc is 3;
three R121 are mutually the same or different;
md is 3; and
three R122 are mutually the same or different.
Among positions *1 to *8 of carbon atoms in a cyclic structure represented by a formula (111a) below in a group represented by the formula (111), L111 is bonded to one of the positions *1 to *4, R121 is bonded to each of three positions of the rest of *1 to *4, L112 is bonded to one of the positions *5 to *8, and R122 is bonded to each of three positions of the rest of *5 to *8.
For instance, in a group represented by the formula (111), when L111 is bonded to a carbon atom at a position *2 in the cyclic structure represented by the formula (111a) and L112 is bonded to a carbon atom at a position *7 in the cyclic structure represented by the formula (111a), the group represented by the formula (111) is represented by a formula (111b) below.
In the formula (111b):
X1, L111, L112, ma, mb, Ar101, R121, R122, R123, R124 and R125 each independently represent the same as X1, L111, L112, ma, mb, Ar101, R121, R122, R123, R124 and R125 in the formula (111);
a plurality of R121 are mutually the same or different; and
a plurality of R122 are mutually the same or different.
In the organic EL device according to the exemplary embodiment, the group represented by the formula (111) is preferably a group represented by the formula (111b).
In the organic EL device according to the exemplary embodiment, it is preferable that ma is 0, 1, or 2, and mb is 0, 1, or 2.
In the organic EL device according to the exemplary embodiment, it is preferable that ma is 0 or 1, and mb is 0 or 1.
In the organic EL device according to the exemplary embodiment, Ar101 is preferably a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, Ar101 is preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted phenanthryl group, or a substituted or unsubstituted fluorenyl group.
In the organic EL device according to the exemplary embodiment, Ar101 is also preferably a group represented by a formula (12), a formula (13), or a formula (14) below.
In the formulae (12), (13) and (14):
R111 to R120 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R124, a group represented by —COOR125, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
* in the formulae (12), (13) and (14) represents a bonding position to L101 in the formula (11), or a bonding position to L112 in the formula (111) or (111b).
The first compound of the organic EL device according to the exemplary embodiment is preferably represented by a formula (101) below.
In the formula (101):
R101 to R120 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
one of R101 to R110 represents a bonding position to L101, and one of R111 to R120 represents a bonding position to L101;
L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
mx is 0, 1, 2, 3, 4, or 5; and
when two or more L101 are present, the two or more L101 are mutually the same or different.
In the first compound represented by the formula (101), it is preferable that: R101 to R110, and R111 to R120 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
one of R101 to R110 represents a bonding position to L101, and one of R111 to R120 represents a bonding position to L101;
L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 24 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 24 ring atoms;
mx is 1, 2, 3, 4, or 5; and
when two or more L101 are present, the two or more L101 are mutually the same or different.
In the organic EL device according to the exemplary embodiment, the first compound is preferably represented by a formula (1010), a formula (1011), a formula (1012), a formula (1013), a formula (1014), or a formula (1015) below.
In the formulae (1010) to (1015):
R101 to R120 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
mx is 0, 1, 2, 3, 4, or 5; and
when two or more L101 are present, the two or more L101 are mutually the same or different.
The compound represented by the formula (1010) corresponds to a compound, in which R103 represents a bonding position to L101 and R120 represents a bonding position to L101.
The compound represented by the formula (1011) corresponds to a compound, in which R103 represents a bonding position to L101 and R111 represents a bonding position to L101.
The compound represented by the formula (1012) corresponds to a compound, in which R103 represents a bonding position to L101 and R118 represents a bonding position to L101.
The compound represented by the formula (1013) corresponds to a compound, in which R102 represents a bonding position to L101 and R111 represents a bonding position to L101.
The compound represented by the formula (1014) corresponds to a compound, in which R102 represents a bonding position to L101 and R118 represents a bonding position to L101.
The compound represented by the formula (1015) corresponds to a compound, in which R105 represents a bonding position to L101 and R118 represents a bonding position to L101.
The first compound of the organic EL device according to the exemplary embodiment is preferably represented by the formula (1010).
In the organic EL device according to the exemplary embodiment, R101 to R110 not being the bonding position to L101 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the organic EL device according to the exemplary embodiment, R101 to R110 not being the bonding position to L101 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, R101 to R110 not being the bonding position to L101 are each preferably a hydrogen atom.
In the organic EL device according to the exemplary embodiment, R111 to R120 not being the bonding position to L101 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the organic EL device according to the exemplary embodiment, R111 to R120 not being the bonding position to L101 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, R111 to R120 not being the bonding position to L101 are each preferably a hydrogen atom.
In the organic EL device according to the exemplary embodiment, it is preferable that L101 is a single bond, or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, it is also preferable that L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 18 ring atoms.
In the organic EL device according to the exemplary embodiment, it is also preferable that L101 is a single bond, or a substituted or unsubstituted arylene group having 6 to 18 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, it is also preferable that L101 is a substituted or unsubstituted arylene group having 6 to 18 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, it is also preferable that L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 13 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 13 ring atoms.
In the organic EL device according to the exemplary embodiment, it is also preferable that L101 is a single bond, or a substituted or unsubstituted arylene group having 6 to 13 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, L101 is also preferably a substituted or unsubstituted arylene group having 6 to 13 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, mx is also preferably 1, 2, or 3.
In the organic EL device according to the exemplary embodiment, mx is also preferably 1 or 2.
In the organic EL device according to the exemplary embodiment, it is also preferable that: mx is 1, 2, or 3; and
L101 is a substituted or unsubstituted arylene group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 18 ring atoms.
In the organic EL device according to the exemplary embodiment, it is also preferable that: mx is 1 or 2; and
L101 is a substituted or unsubstituted arylene group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 18 ring atoms.
In the organic EL device according to the exemplary embodiment, it is also preferable that: mx is 1 or 2; and
L101 is a substituted or unsubstituted arylene group having 6 to 18 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, the first compound is preferably represented by a formula (102) below.
In the formula (102):
R101 to R120 each independently represent the same as R101 to R120 in the formula (101);
one of R101 to R110 represents a bonding position to L111, and one of R111 to R120 represents a bonding position to L112;
X1 is CR123R124, an oxygen atom, a sulfur atom, or NR125;
L111 and L112 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
ma is 0, 1, 2, 3, or 4;
mb is 0, 1, 2, 3, or 4;
ma+mb is 0, 1, 2, 3, or 4;
R121, R122, R123, R124 and R125 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mc is 3;
three R121 are mutually the same or different;
md is 3; and
three R122 are mutually the same or different.
In the compound represented by the formula (102), it is preferable that: ma is 0, 1, or 2, and mb is 0, 1, or 2.
In the compound represented by the formula (102), it is preferable that: ma is 0 or 1, and mb is 0 or 1.
In the compound represented by the formula (102), it is preferable that L111 and L112 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 24 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 24 ring atoms.
In the compound represented by the formula (102), it is preferable that: ma is 1, 2, or 3,
mb is 1, 2, or 3, and
ma+mb is 2, 3 or 4.
In the compound represented by the formula (102), it is preferable that: ma is 1 or 2, and
mb is 1 or 2.
In the compound represented by the formula (102), it is preferable that: ma is 1, and
mb is 1.
In the organic EL device according to the exemplary embodiment, R101 to R110 not being the bonding position to L111 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the organic EL device according to the exemplary embodiment, R101 to R110 not being the bonding position to L111 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, R101 to R110 not being the bonding position to L111 are each preferably a hydrogen atom.
In the organic EL device according to the exemplary embodiment, R111 to R120 not being the bonding position to L112 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the organic EL device according to the exemplary embodiment, R111 to R120 not being the bonding position to L112 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, R111 to R120 not being the bonding position to L112 are each preferably a hydrogen atom.
In the organic EL device according to the exemplary embodiment, it is preferable that two or more of R101 to R110 are each a group represented by the formula (11).
In the organic EL device according to the exemplary embodiment, it is preferable that two or more of R101 to R110 are each a group represented by the formula (11) and Ar101 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, it is preferable that Ar101 is not a substituted or unsubstituted pyrenyl group,
L101 is not a substituted or unsubstituted pyrenylene group, and
the substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms as R101 to R110 not being the group represented by the formula (11) is not a substituted or unsubstituted pyrenyl group.
In the organic EL device according to the exemplary embodiment, it is preferable that R101 to R110 not being the group represented by the formula (11) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the organic EL device according to the exemplary embodiment, it is preferable that R101 to R110 not being the group represented by the formula (11) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, R101 to R110 not being the group represented by the formula (11) are each preferably a hydrogen atom.
In the first compound and the second compound, it is preferable that all groups described as “substituted or unsubstituted” groups are “unsubstituted” groups.
In the organic EL device according to the exemplary embodiment, for instance, two of R101 to R110 in the first compound represented by the formula (1) are each a group represented by the formula (11).
In the organic EL device according to the exemplary embodiment, for instance, three of R101 to R110 in the first compound represented by the formula (1) are each a group represented by the formula (11).
In the organic EL device according to the exemplary embodiment, for instance, four of R101 to R110 in the first compound represented by the formula (1) are each a group represented by the formula (11).
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11) and mx is 1 or more.
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11), mx is 0, and Ar101 is a substituted or unsubstituted aryl group.
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11), mx is 0, and Ar101 is a substituted or unsubstituted heterocyclic group containing a nitrogen atom.
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11), mx is 0, and Ar101 is a substituted or unsubstituted heterocyclic group containing a sulfur atom.
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11), mx is 0, and Ar101 is substituted or unsubstituted furyl group, oxazolyl group, isoxazolyl group, oxadiazolyl group, xanthenyl group, benzofuranyl group, isobenzofuranyl group, dibenzofuranyl group, benzoxazolyl group, benzisoxazolyl group, phenoxazinyl group, morpholino group, dinaphthofuranyl group, azadibenzofuranyl group, diazadibenzofuranyl group, azanaphthobenzofuranyl group, and diazanaphthobenzofuranyl group.
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11), mx is 0, and Ar101 is at least one group selected from the group consisting of unsubstituted furyl group, oxazolyl group, isoxazolyl group, oxadiazolyl group, xanthenyl group, benzofuranyl group, isobenzofuranyl group, dibenzofuranyl group, benzoxazolyl group, benzisoxazolyl group, phenoxazinyl group, morpholino group, dinaphthofuranyl group, azadibenzofuranyl group, diazadibenzofuranyl group, azanaphthobenzofuranyl group, and diazanaphthobenzofuranyl group.
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11), mx is 0, and Ar101 is a substituted or unsubstituted dibenzofuranyl group.
In the organic EL device according to the exemplary embodiment, for instance, one of R101 to R110 in the first compound represented by the formula (1) is a group represented by the formula (11), mx is 0, and Ar101 is an unsubstituted dibenzofuranyl group.
In the organic EL device according to the exemplary embodiment, for instance, mx in the first compound represented by the formula (101) is 2 or more.
In the organic EL device according to the exemplary embodiment, for instance, mx in the first compound represented by the formula (101) is 1 or more, and L101 is an arylene group having 6 to 24 ring carbon atoms or a divalent heterocyclic group having 5 to 24 ring atoms.
In the organic EL device according to the exemplary embodiment, for instance, mx in the first compound represented by the formula (101) is 1 or more, and L101 is an arylene group having 6 to 18 ring carbon atoms or a divalent heterocyclic group having 5 to 18 ring atoms.
In the organic EL device according to the exemplary embodiment, the first compound is also preferably a compound represented by the formula (1X).
In the formula (1X):
R101 to R112 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (11X);
at least one of R101 to R112 is the group represented by the formula (11X);
when a plurality of groups represented by the formula (11X) are present, the plurality of groups represented by the formula (11X) are mutually the same or different;
L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar101 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx is 1, 2, 3, 4, or 5;
when two or more L101 are present, the two or more L101 are mutually the same or different;
when two or more Ar101 are present, the two or more Ar101 are mutually the same or different; and
* in the formula (11X) represents a bonding position to a benz[a]anthracene ring in the formula (1X).
In the organic EL device according to the exemplary embodiment, the group represented by the formula (11X) is preferably a group represented by a formula (111X) below.
In the formula (111X):
X1 is CR143R144, an oxygen atom, a sulfur atom, or NR145;
L111 and L112 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
ma is 1, 2, 3, or 4;
mb is 1, 2, 3, or 4;
ma+mb is 2, 3, or 4;
Ar101 represents the same as Ar101 in the formula (11X);
R141, R142, R143, R144 and R145 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mc is 3;
three R141 are mutually the same or different;
md is 3; and
three R142 are mutually the same or different.
Among positions *1 to *8 of carbon atoms in a cyclic structure represented by a formula (111aX) below in the group represented by the formula (111X), L111 is bonded to one of the positions *1 to *4, R141 is bonded to each of three positions of the rest of *1 to *4, L112 is bonded to one of the positions *5 to *8, and R142 is bonded to each of three positions of the rest of *5 to *8.
For instance, when L111 is bonded to a carbon atom at position *2 in the cyclic structure represented by the formula (111aX) and L112 is bonded to a carbon atom at position *7 in the cyclic structure represented by the formula (111aX) in the group represented by the formula (111X), the group represented by the formula (111X) is represented by a formula (111 bX) below.
In the formula (111 bX):
X1, L111, L112, ma, mb, Ar101, R141, R142, R143, R144 and R145 each independently represent the same as X1, L111, L112, ma, mb, Ar101, R141, R142, R143, R144 and R145 in the formula (111X);
a plurality of R141 are mutually the same or different; and
a plurality of R142 are mutually the same or different.
In the organic EL device according to the exemplary embodiment, the group represented by the formula (111X) is preferably the group represented by the formula (111bX).
In the compound represented by the formula (1X), it is preferable that ma is 1 or 2 and mb is 1 or 2.
In the compound represented by the formula (1X), it is preferable that ma is 1 and mb is 1.
In the compound represented by the formula (1X), Ar101 is preferably a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In the compound represented by the formula (1X), Ar101 is preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted benz[a]anthryl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted phenanthryl group, or a substituted or unsubstituted fluorenyl group.
The compound represented by the formula (1X) is also preferably represented by a formula (101X) below.
In the formula (101X):
one of R111 and R112 represents a bonding position to L101 and one of R133 and R134 represents a bonding position to L101;
R101 to R110, R121 to R130, R111 or R112 that is not a bonding position to L101, and R133 or R134 that is not a bonding position to L101 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
L101 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
mx is 1, 2, 3, 4, or 5; and
when two or more L101 are present, the two or more L101 are mutually the same or different.
In the compound represented by the formula (1X), L101 is preferably a single bond or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms.
The compound represented by the formula (1X) is also preferably represented by a formula (102X) below.
In the formula (102X):
one of R111 and R112 represents a bonding position to L111 and one of R133 and R134 represents a bonding position to L112;
R101 to R110, R121 to R130, R111 or R112 that is not a bonding position to L111, and R133 or R134 that is not a bonding position to L112 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
X1 is CR143R144, an oxygen atom, a sulfur atom, or NR145;
L111 and L112 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
ma is 1, 2, 3, or 4;
mb is 1, 2, 3, or 4;
ma+mb is 2, 3, 4 or 5;
R141, R142, R143, R144 and R145 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mc is 3;
three R141 are mutually the same or different;
md is 3; and
three R142 are mutually the same or different.
In the compound represented by the formula (1X), it is preferable that ma is 1 or 2 and mb is 1 or 2 in the formula (102X).
In the compound represented by the formula (1X), it is preferable that ma is 1 and mb is 1 in the formula (102X).
In the compound represented by the formula (1X), the group represented by the formula (11X) is also preferably a group represented by a formula (11AX) below or a group represented by a formula (11BX) below.
In the formulae (11AX) and (11BX):
R121 to R131 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
when a plurality of groups represented by the formula (11AX) are present, the plurality of groups represented by the formula (11AX) are mutually the same or different;
when a plurality of groups represented by the formula (11BX) are present, the plurality of groups represented by the formula (11BX) are mutually the same or different;
L131 and L132 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
* in each of the formulae (11AX) and (11BX) represents a bonding position to a benz[a]anthracene ring in the formula (1X).
The compound represented by the formula (1X) is also preferably represented by a formula (103X) below.
In the formula (103X):
R101 to R110 and R112 respectively represent the same as R101 to R110 and R112 in the formula (1X); and
R121 to R131, L131, and L132 respectively represent the same as R121 to R131, L131, and L132 in the formula (11BX).
In the compound represented by the formula (1X), L131 is also preferably a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms.
In the compound represented by the formula (1X), L132 is also preferably a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms.
In the compound represented by the formula (1X), two or more of R101 to R112 are each also preferably a group represented by the formula (11X).
In the compound represented by the formula (1X), it is preferable that two or more of R101 to R112 are each a group represented by the formula (11X) and Ar101 in the formula (11X) is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In the compound represented by the formula (1X): it is also preferable that Ar101 is not a substituted or unsubstituted benz[a]anthryl group, L101 is not a substituted or unsubstituted benz[a]anthrylene group, and the substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms for R101 to R110 not being the group represented by the formula (11X) is not a substituted or unsubstituted benz[a]anthryl group.
In the compound represented by the formula (1X), R101 to R112 not being the group represented by the formula (11X) are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the compound represented by the formula (1X), R101 to R112 not being the group represented by the formula (11X) are each preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms.
In the compound represented by the formula (1X), R101 to R112 not being the group represented by the formula (11X) are each preferably a hydrogen atom.
In the organic EL device according to the exemplary embodiment, the first compound is also preferably a compound represented by the formula (12X).
In the formula (12X):
at least one combination of adjacent two or more of R1201 to R1210 are mutually bonded to form a substituted or unsubstituted monocyclic ring, or mutually bonded to form a substituted or unsubstituted fused ring;
R1201 to R1210 not forming the substituted or unsubstituted monocyclic ring and not forming the substituted or unsubstituted fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (121);
at least one of a substituent, if present, for the substituted or unsubstituted monocyclic ring, a substituent, if present, for the substituted or unsubstituted fused ring, or R1201 to R1210 are a group represented by the formula (121);
when a plurality of groups represented by the formula (121) are present, the plurality of groups represented by the formula (121) are mutually the same or different;
L1201 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar1201 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx2 is 0, 1, 2, 3, 4, or 5;
when two or more L1201 are present, the two or more L1201 are mutually the same or different;
when two or more Ar1201 are present, the two or more Ar1201 are mutually the same or different; and
* in the formula (121) represents a bonding position to a ring represented by the formula (12X).
In the formula (12X), combinations of adjacent two of R1201 to R1210 refer to a combination of R1201 and R1202, a combination of R1202 and R1203, a combination of R1203 and R1204, a combination of R1204 and R1205, a combination of R1205 and R1206, a combination of R1207 and R1208, a combination of R1208 and R1209, and a combination of R1209 and R1210.
In the organic EL device according to the exemplary embodiment, the first compound is also preferably a compound represented by the formula (13X) below.
In the formula (13X):
R1301 to R1310 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (131), at least one of R1301 to R1310 is the group represented by the formula (131);
when a plurality of groups represented by the formula (131) are present, the plurality of groups represented by the formula (131) are mutually the same or different;
L1301 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar1301 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx3 is 0, 1, 2, 3, 4, or 5;
when two or more L1301 are present, the two or more L1301 are mutually the same or different;
when two or more Ar1301 are present, the two or more Ar1301 are mutually the same or different; and
* in the formula (131) represents a bonding position to a fluoranthene ring represented by the formula (13X).
In the organic EL device of the exemplary embodiment, none of combinations of adjacent two or more of R1301 to R1310 not being the group represented by the formula (131) are bonded to each other. Combinations of adjacent two of R1301 to R1310 in the formula (13X) refer to a combination of R1301 and R1302, a combination of R1302 and R1303, a combination of R1303 and R1304, a combination of R1304 and R1305, a combination of R1305 and R1306, a combination of R1307 and R1308, a combination of R1308 and R1309, and a combination of R1309 and R1310.
In the organic EL device of the exemplary embodiment, the first compound is also preferably a compound represented by the formula (14X) below.
In the formula (14X):
R1401 to R1410 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (141);
at least one of R1401 to R1410 is the group represented by the formula (141);
when a plurality of groups represented by the formula (141) are present, the plurality of groups represented by the formula (141) are mutually the same or different;
L1401 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar1401 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx4 is 0, 1, 2, 3, 4, or 5;
when two or more L1401 are present, the two or more L1401 are mutually the same or different;
when two or more Ar1401 are present, the two or more Ar1401 are mutually the same or different; and
* in the formula (141) represents a bonding position to a ring represented by the formula (14X).
In the organic EL device of the exemplary embodiment, the first compound is also preferably a compound represented by the formula (15X) below.
In the formula (15X):
R1501 to R1514 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (151);
at least one of R1501 to R1514 is the group represented by the formula (151);
when a plurality of groups represented by the formula (151) are present, the plurality of groups represented by the formula (151) are mutually the same or different;
L1501 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar1501 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx5 is 0, 1, 2, 3, 4, or 5;
when two or more L1501 are present, the two or more L1501 are mutually the same or different;
when two or more Ar1501 are present, the two or more Ar1501 are mutually the same or different; and
* in the formula (151) represents a bonding position to a ring represented by the formula (15X).
In the organic EL device according to the exemplary embodiment, the first compound is also preferably a compound represented by the formula (16X) below.
In the formula (16X):
R1601 to R1614 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (161);
at least one of R1601 to R1614 is the group represented by the formula (161); when a plurality of groups represented by the formula (161) are present, the plurality of groups represented by the formula (161) are mutually the same or different;
L1601 is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar1601 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx6 is 0, 1, 2, 3, 4, or 5;
when two or more L1601 are present, the two or more L1601 are mutually the same or different;
when two or more Ar101 are present, the two or more Ar1601 are mutually the same or different; and
* in the formula (161) represents a bonding position to a ring represented by the formula (16X).
In the first compound and the second compound, all groups described as “substituted or unsubstituted” groups are preferably “unsubstituted” groups.
The first compound can be manufactured by a known method. The first compound can also be manufactured based on a known method through a known alternative reaction using a known material(s) tailored for the target compound.
Specific examples of the first compound include the following compounds. It should however be noted that the invention is not limited to the specific examples of the first compound.
In the specific examples of the compound herein, D represents a deuterium atom, Me represents a methyl group, tBu represents a tert-butyl group, and Ph represents a phenyl group.
In the organic EL device according to the exemplary embodiment, the second host material is also preferably an anthracene derivative.
In the organic EL device according to the exemplary embodiment, the second host material is also preferably the second compound represented by the formula (2).
In the formula (2):
R201 to R208 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
L201 and L202 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms; and
Ar201 and Ar202 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the second compound according to the exemplary embodiment, R901, R902, R903, R904, R905, R906, R907, R801 and R802 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
when a plurality of R901 are present, the plurality of R901 are mutually the same or different;
when a plurality of R902 are present, the plurality of R902 are mutually the same or different;
when a plurality of R903 are present, the plurality of R903 are mutually the same or different;
when a plurality of R904 are present, the plurality of R904 are mutually the same or different;
when a plurality of R905 are present, the plurality of R905 are mutually the same or different;
when a plurality of R906 are present, the plurality of R906 are mutually the same or different;
when a plurality of R907 are present, the plurality of R907 are mutually the same or different;
when a plurality of R801 are present, the plurality of R801 are mutually the same or different; and
when a plurality of R802 are present, the plurality of R802 are mutually the same or different.
In the organic EL device according to the exemplary embodiment, it is preferable that R201 to R208 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —C(═O)R801, a group represented by —COOR802, a halogen atom, a cyano group, or a nitro group; L201 and L202 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
Ar201 and Ar202 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the organic EL device according to the exemplary embodiment, it is preferable that L201 and L202 are each independently a single bond, or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms; and Ar201 and Ar202 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, it is preferable that Ar201 and Ar202 are each independently a phenyl group, a naphthyl group, phenanthryl group, a biphenyl group, a terphenyl group, a diphenylfluorenyl group, a dimethylfluorenyl group, a benzodiphenylfluorenyl group, a benzodimethylfluorenyl group, a dibenzofuranyl group, a dibenzothienyl group, a naphthobenzofuranyl group, or a naphthobenzothienyl group.
In the organic EL device according to the exemplary embodiment, the second compound represented by the formula (2) is preferably a compound represented by a formula (201), (202), (203), (204), (205), (206), (207), (208) or (209) below.
In the formulae (201) to (209):
L201 and Ar201 represent the same as L201 and Ar201 in the formula (2); and
R201 to R208 each independently represent the same as R201 to R208 in the formula (2).
The second compound represented by the formula (2) is also preferably a compound represented by a formula (221), (222), (223), (224), (225), (226), (227), (228) or (229) below.
In the formulae (221), (222), (223), (224), (225), (226), (227), (228) and (229):
R201 and R203 to R208 each independently represent the same as R201 and R203 to R208 in the formula (2);
L201 and Ar201 respectively represent the same as L201 and Ar201 in the formula (2);
L203 represents the same as L201 in the formula (2);
L203 and L201 are mutually the same or different;
Ar203 represents the same as Ar201 in the formula (2); and
Ar203 and Ar201 are mutually the same or different.
The second compound represented by the formula (2) is also preferably a compound represented by a formula (241), (242), (243), (244), (245), (246), (247), (248) or (249) below.
In the formulae (241), (242), (243), (244), (245), (246), (247), (248) and (249):
R201, R202 and R204 to R208 each independently represent the same as R201, R202 and R204 to R208 in the formula (2);
L201 and Ar201 respectively represent the same as L201 and Ar201 in the formula (2);
L203 represents the same as L201 in the formula (2);
L203 and L201 are mutually the same or different;
Ar203 represents the same as Ar201 in the formula (2); and
Ar203 and Ar201 are mutually the same or different.
It is preferable that R201 to R208 in the second compound represented by the formula (2) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, or a group represented by —Si(R901)(R902)(R903).
It is preferable that: L201 is a single bond, or an unsubstituted arylene group having 6 to 22 ring carbon atoms; and
Ar201 is a substituted or unsubstituted aryl group having 6 to 22 ring carbon atoms.
In the organic EL device according to the exemplary embodiment, R201 to R208 that are substituents on an anthracene skeleton in the second compound represented by the formula (2) are preferably hydrogen atoms in terms of preventing inhibition of intermolecular interaction to inhibit a decrease in electron mobility.
However, R201 to R208 may be a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
Assuming that R201 to R208 each are a bulky substituent such as an alkyl group and a cycloalkyl group, intermolecular interaction may be inhibited to decrease the electron mobility of the second compound relative to that of the first host material, so that a relationship of μe(H1)<μe(H2) shown by the numerical formula (Numerical Formula 33) may not be satisfied. When the second compound is used in the second emitting layer, it can be expected that satisfying the relationship of μe(H1)<μe(H2) inhibits a decrease in a recombination ability between holes and electrons in the first emitting layer and a decrease in a luminous efficiency. It should be noted that substituents, namely, a haloalkyl group, alkenyl group, alkynyl group, group represented by —Si(R901)(R902)(R903), group represented by —O—(R904), group represented by —S—(R905), group represented by —N(R906)(R907), aralkyl group, group represented by —C(═O)R801, group represented by —COOR802, halogen atom, cyano group, and nitro group are likely to be bulky, and an alkyl group and cycloalkyl group are likely to be further bulky.
In the second compound represented by the formula (2), R201 to R208, which are the substituents on the anthracene skeleton, are each preferably not a bulky substituent and preferably not an alkyl group and cycloalkyl group. More preferably, R201 to R208 are not an alkyl group, cycloalkyl group, haloalkyl group, alkenyl group, alkynyl group, group represented by —Si(R901)(R902)(R903), group represented by —O—(R904), group represented by —S—(R905), group represented by —N(R906)(R907), aralkyl group, group represented by —C(═O)R801, group represented by —COOR802, halogen atom, cyano group, and nitro group.
In the organic EL device according to the exemplary embodiment, R201 to R208 in the second compound represented by the formula (2) are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, or a group represented by —Si(R901)(R902)(R903).
In the organic EL device according to the exemplary embodiment, R201 to R208 in the second compound represented by the formula (2) are preferably a hydrogen atom.
In the second compound, examples of the substituent for a “substituted or unsubstituted” group on R201 to R208 also preferably do not include the above-described substituent that is likely to be bulky, especially a substituted or unsubstituted alkyl group and a substituted or unsubstituted cycloalkyl group. Since examples of the substituent for a “substituted or unsubstituted” group on R201 to R208 do not include a substituted or unsubstituted alkyl group and a substituted or unsubstituted cycloalkyl group, inhibition of intermolecular interaction to be caused by presence of a bulky substituent such as an alkyl group and a cycloalkyl group can be prevented, thereby preventing a decrease in the electron mobility. Moreover, when the second compound described above is used in the second emitting layer, a decrease in a recombination ability between holes and electrons in the first emitting layer and a decrease in the luminous efficiency can be inhibited.
It is more preferable that R201 to R208, which are the substituents on the anthracene skeleton, are not bulky substituents, and R201 to R208 as substituents are unsubstituted. Assuming that R201 to R208, which are the substituents on the anthracene skeleton, are not bulky substituents and substituents are bonded to R201 to R208 which are the not-bulky substituents, the substituents bonded to R201 to R208 are preferably not the bulky substituents; the substituents bonded to R201 to R208 serving as substituents are preferably not an alkyl group and cycloalkyl group, more preferably not an alkyl group, cycloalkyl group, haloalkyl group, alkenyl group, alkynyl group, group represented by —Si(R901)(R902)(R903), group represented by —O—(R904), group represented by —S—(R905), group represented by —N(R906)(R907), aralkyl group, group represented by —C(═O)R801, group represented by —COOR802, halogen atom, cyano group, and nitro group.
In the second compound, all groups described as “substituted or unsubstituted” groups are preferably “unsubstituted” groups.
In the organic EL device according to the exemplary embodiment, for instance, Ar201 in the second compound represented by the formula (2) is a substituted or unsubstituted dibenzofuranyl group.
In the organic EL device according to the exemplary embodiment, for instance, Ar201 in the second compound represented by the formula (2) is an unsubstituted dibenzofuranyl group.
In the organic EL device according to the exemplary embodiment, for instance, the second compound represented by the formula (2) has at least one hydrogen atom, the hydrogen atom including at least one deuterium atom.
In the organic EL device according to the exemplary embodiment, for instance, L201 in the second compound represented by the formula (2) is one of TEMP-63 to TEMP-68.
In the organic EL device according to the exemplary embodiment, for instance, Ar201 in the second compound represented by the formula (2) is at least one group selected from the group consisting of substituted or unsubstituted anthryl group, benzanthryl group, phenanthryl group, benzophenanthryl group, phenalenyl group, pyrenyl group, chrysenyl group, benzochrysenyl group, triphenylenyl group, benzotriphenylenyl group, tetracenyl group, pentacenyl group, fluoranthenyl group, benzofluoranthenyl group, and perylenyl group.
In the organic EL device according to the exemplary embodiment, for instance, Ar201 in the second compound represented by the formula (2) is a substituted or unsubstituted fluorenyl group.
In the organic EL device according to the exemplary embodiment, for instance, Ar201 in the second compound represented by the formula (2) is a substituted or unsubstituted xanthenyl group.
In the organic EL device according to the exemplary embodiment, for instance, Ar201 in the second compound represented by the formula (2) is a benzoxanthenyl group.
The second compound can be manufactured by a known method. The second compound can also be manufactured based on a known method through a known alternative reaction using a known material(s) tailored for the target compound.
Specific examples of the second compound include the following compounds. It should however be noted that the invention is not limited to the specific examples of the second compound.
In the organic EL device according to the exemplary embodiment, examples of the first emitting compound, the second emitting compound and the third emitting compound include a third compound and a fourth compound below. The third compound and the fourth compound are each independently at least one compound selected from the group consisting of a compound represented by a formula (3) below, a compound represented by a formula (4) below, a compound represented by a formula (5) below, a compound represented by a formula (6) below, a compound represented by a formula (7) below, a compound represented by a formula (8) below, a compound represented by a formula (9) below, and a compound represented by a formula (10) below.
The compound represented by the formula (3) will be described.
In the formula (3):
at least one combination of adjacent two or more of R301 to R310 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one of R301 to R310 is a monovalent group represented by a formula (31) below; and
R301 to R310 forming neither the monocyclic ring nor the fused ring and not being the monovalent group represented by the formula (31) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the formula (31):
Ar301 and Ar302 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
L301 to L303 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms; and
* represents a bonding position to a pyrene ring in the formula (3).
In the third and fourth compounds, R901, R902, R903, R904, R905, R906, and R907 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms;
when a plurality of R901 are present, the plurality of R901 are mutually the same or different;
when a plurality of R902 are present, the plurality of R902 are mutually the same or different;
when a plurality of R903 are present, the plurality of R903 are mutually the same or different;
when a plurality of R904 are present, the plurality of R904 are mutually the same or different;
when a plurality of R905 are present, the plurality of R905 are mutually the same or different;
when a plurality of R906 are present, the plurality of R906 are mutually the same or different; and
when a plurality of R907 are present, the plurality of R907 are mutually the same or different.
In the formula (3), it is preferable that two of R301 to R310 are each a group represented by the formula (31).
In an exemplary embodiment, the compound represented by the formula (3) is a compound represented by a formula (33) below.
In the formula (33):
R311 to R318 each independently represent the same as R301 to R310 in the formula (3) that are not the monovalent group represented by the formula (31);
L311 to L316 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms; and
Ar312, Ar313, Ar315, and Ar316 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the formula (31), L301 is preferably a single bond, and L302 and L303 are each preferably a single bond.
In an exemplary embodiment, the compound represented by the formula (3) is represented by a formula (34) or a formula (35) below.
In the formula (34):
R311 to R318 each independently represent the same as R301 to R310 in the formula (3) that are not the monovalent group represented by the formula (31);
L312, L313, L315 and L316 each independently represent the same as L312, L313, L315 and L316 in the formula (33); and
Ar312, Ar313, Ar315 and Ar316 each independently represent the same as Ar312, Ar313, Ar315 and Ar316 in the formula (33).
In the formula (35):
R311 to R318 each independently represent the same as R301 to R310 in the formula (3) that are not the monovalent group represented by the formula (31); and
Ar312, Ar313, Ar315 and Ar316 each independently represent the same as Ar312, Ar313, Ar315 and Ar316 in the formula (33).
In the formula (31), at least one of Ar301 or Ar302 is preferably a group represented by a formula (36) below.
In the formulae (33) to (35), at least one of Ar312 or Ar313 is preferably a group represented by the formula (36) below.
In the formulae (33) to (35), at least one of Ar315 or Ar316 is preferably a group represented by the formula (36) below.
In the formula (36):
X3 represents an oxygen atom or a sulfur atom;
at least one combination of adjacent two or more of R321 to R327 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R321 to R327 forming neither the monocyclic ring nor the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
* represents a bonding position to L302, L303, L312, L313, L315, or L316.
X3 is preferably an oxygen atom.
At least one of R321 to R327 is preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the formula (31), it is preferable that Ar301 is a group represented by the formula (36) and Ar302 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In the formulae (33) to (35), it is preferable that Ar312 is a group represented by the formula (36) and Ar313 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In the formulae (33) to (35), it is preferable that Ar315 is a group represented by the formula (36) and Ar316 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, the compound represented by the formula (3) is represented by a formula (37) below.
In the formula (37):
R311 to R318 each independently represent the same as R301 to R310 in the formula (3) that are not the monovalent group represented by the formula (31);
at least one combination of adjacent two or more of R321 to R327 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one combination of adjacent two or more of R341 to R347 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R321 to R327 and R341 to R347 forming neither the monocyclic ring nor the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
R331 to R335 and R351 to R355 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
Specific examples of the compound represented by the formula (3) include compounds shown below.
The compound represented by the formula (4) will be described.
In the formula (4):
Z is each independently CRa or a nitrogen atom;
A1 ring and A2 ring are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms;
when a plurality of Ra are present, at least one combination of adjacent two or more of the plurality of Ra are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
n21 and n22 are each independently 0, 1, 2, 3, or 4;
when a plurality of Rb are present, at least one combination of adjacent two or more of the plurality of Rb are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
when a plurality of Rc are present, at least one combination of adjacent two or more of the plurality of Rc are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
Ra, Rb, and Rc forming neither the monocyclic ring nor the fused ring are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
The “aromatic hydrocarbon ring” for the A1 ring and A2 ring has the same structure as a compound formed by introducing a hydrogen atom to the “aryl group” described above.
Ring atoms of the “aromatic hydrocarbon ring” for the A1 ring and the A2 ring include two carbon atoms on a fused bicyclic structure at the center of the formula (4).
Specific examples of the “substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms” include a compound formed by introducing a hydrogen atom to the “aryl group” described in the specific example group G1.
The “heterocycle” for the A1 ring and A2 ring has the same structure as a compound formed by introducing a hydrogen atom to the “heterocyclic group” described above.
Ring atoms of the “heterocycle” for the A1 ring and the A2 ring include two carbon atoms on a fused bicyclic structure at the center of the formula (4).
Specific examples of the “substituted or unsubstituted heterocycle having 5 to 50 ring atoms” include a compound formed by introducing a hydrogen atom to the “heterocyclic group” described in the specific example group G2.
Rb is bonded to any one of carbon atoms forming the aromatic hydrocarbon ring for the A1 ring or any one of the atoms forming the heterocycle for the A1 ring.
Rc is bonded to any one of carbon atoms forming the aromatic hydrocarbon ring for the A2 ring or any one of the atoms forming the heterocycle for the A2 ring.
At least one of Ra, Rb, or Rc is preferably a group represented by a formula (4a) below. More preferably, at least two of Ra, Rb, and Rc are groups represented by the formula (4a).
*-L401-Ar401 (4a)
In the formula (4a):
L401 is a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms; and
Ar401 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by a formula (4b) below.
In the formula (4b):
L402 and L403 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms;
a combination of Ar402 and Ar403 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
Ar402 and Ar403 forming neither the monocyclic ring nor the fused ring are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, the compound represented by the formula (4) is represented by a formula (42) below.
In the formula (42):
at least one combination of adjacent two or more of R401 to R411 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R401 to R411 forming neither the monocyclic ring nor the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
At least one of R401 to R411 is preferably a group represented by the formula (4a). More preferably, at least two of R401 to R411 are each a group represented by the formula (4a).
R404 and R411 are each preferably a group represented by the formula (4a).
In an exemplary embodiment, the compound represented by the formula (4) is a compound formed by bonding a structure represented by a formula (4-1) or a formula (4-2) below to the A1 ring.
Further, in an exemplary embodiment, the compound represented by the formula (42) is a compound formed by bonding a structure represented by the formula (4-1) or the formula (4-2) to the ring bonded with R404 to R407.
In the formula (4-1), two bonds * are each independently bonded to a ring-forming carbon atom of the aromatic hydrocarbon ring or a ring atom of the heterocycle for the A1 ring in the formula (4) or bonded to one of R404 to R407 in the formula (42);
in the formula (4-2), three bonds * are each independently bonded to a ring-forming carbon atom of the aromatic hydrocarbon ring or a ring atom of the heterocycle for the A1 ring in the formula (4) or bonded to one of R404 to R407 in the formula (42);
at least one combination of adjacent two or more of R421 to R427 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
at least one combination of adjacent two or more of R431 to R438 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R421 to R427 and R431 to R438 forming neither the monocyclic ring nor the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, the compound represented by the formula (4) is a compound represented by a formula (41-3), a formula (41-4), or a formula (41-5) below.
In the formulae (41-3), (41-4) and (41-5):
A1 ring is as defined for the formula (4);
R421 to R427 each independently represent the same as R421 to R427 in the formula (4-1); and
R440 to R448 each independently represent the same as R401 to R411 in the formula (42).
In an exemplary embodiment, a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms for the A1 ring in the formula (41-5) is a substituted or unsubstituted naphthalene ring, or a substituted or unsubstituted fluorene ring.
In an exemplary embodiment, a substituted or unsubstituted heterocycle having 5 to 50 ring atoms for the A1 ring in the formula (41-5) is a substituted or unsubstituted dibenzofuran ring, a substituted or unsubstituted carbazole ring, or a substituted or unsubstituted dibenzothiophene ring.
In an exemplary embodiment, the compound represented by the formula (4) or the formula (42) is selected from the group consisting of compounds represented by formulae (461) to (467) below.
In the formulae (461), (462), (463), (464), (465), (466) and (467):
R421 to R427 each independently represent the same as R421 to R427 in the formula (4-1);
R431 to R438 each independently represent the same as R431 to R438 in the formula (4-2);
R440 to R448 and R451 to R454 each independently represent the same as R401 to R411 in the formula (42);
X4 is an oxygen atom, NR801, or C(R802)(R803);
R801, R802, and R803 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms;
when a plurality of R801 are present, the plurality of R801 are mutually the same or different;
when a plurality of R802 are present, the plurality of R802 are mutually the same or different; and
when a plurality of R803 are present, the plurality of R803 are mutually the same or different.
In an exemplary embodiment, in a compound represented by the formula (42), at least one combination of adjacent two or more of R401 to R411 are mutually bonded to form a substituted or unsubstituted monocyclic ring or a substituted or unsubstituted fused ring. The compound represented by the formula (42) in the exemplary embodiment is described in detail as a compound represented by a formula (45).
The compound represented by the formula (45) will be described.
In the formula (45):
two or more of combinations selected from the group consisting of a combination of R461 and R462, a combination of R462 and R463, a combination of R464 and R465, a combination of R465 and R466, a combination of R466 and R467, a combination of R468 and R469, a combination of R469 and R470, and a combination of R470 and R471 are mutually bonded to form a substituted or unsubstituted monocyclic ring or a substituted or unsubstituted fused ring;
the combination of R461 and R462 and the combination of R462 and R463, the combination of R464 and R465 and the combination of R465 and R466, the combination of R465 and R466 and the combination of R466 and R467, the combination of R468 and R469 and the combination of R469 and R470, and the combination of R469 and R470 and the combination of R470 and R471 do not form a ring at the same time;
at least two rings formed by R461 to R471 are mutually the same or different; and
R461 to R471 forming neither the monocyclic ring nor the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the formula (45), Rn and Rn+1 (n being an integer selected from 461, 462, 464 to 466, and 468 to 470) are mutually bonded to form a substituted or unsubstituted monocyclic ring or fused ring together with two ring-forming carbon atoms bonded with Rn and Rn+1. The ring is preferably formed of atoms selected from the group consisting of a carbon atom, an oxygen atom, a sulfur atom, and a nitrogen atom, and is preferably made of 3 to 7, more preferably 5 or 6 atoms.
The number of the above cyclic structures in the compound represented by the formula (45) is, for instance, 2, 3, or 4. The two or more of the cyclic structures may be present on the same benzene ring on the basic skeleton represented by the formula (45) or may be present on different benzene rings. For instance, when three cyclic structures are present, each of the cyclic structures may be present on corresponding one of the three benzene rings of the formula (45).
Examples of the above cyclic structures in the compound represented by the formula (45) include structures represented by formulae (451) to (460) below.
In the formulae (451) to (457):
each combination of *1 and *2, *3 and *4, *5 and *6, *7 and *8, *9 and *10, *11 and *12, and *13 and *14 represent the two ring-forming carbon atoms bonded with Rn and Rn+1;
the ring-forming carbon atom bonded with Rn may be any one of the two ring-forming carbon atoms represented by *1 and *2, *3 and *4, *5 and *6, *7 and *8, *9 and *10, *11 and *12, and *13 and *14;
X45 is C(R4512)(R4513), NR4514, an oxygen atom, or a sulfur atom;
at least one combination of adjacent two or more of R4501 to R4506 and R4512 to R4513 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R4501 to R4514 forming neither the monocyclic ring nor the fused ring each independently represent the same as R461 to R471 in the formula (45).
In the formulae (458) to (460):
each combination of *1 and *2, and *3 and *4 represent the two ring-forming carbon atoms bonded with Rn and Rn+1;
the ring-forming carbon atom bonded with Rn may be any one of the two ring-forming carbon atoms represented by *1 and *2, or *3 and *4;
X45 is C(R4512)(R4513), NR4514, an oxygen atom, or a sulfur atom;
at least one combination of adjacent two or more of R4512, R4513 and R4515 to R4525 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R4512 to R4513, R4515 to R4521 and R4522 to R4525 not forming the monocyclic ring and not forming the fused ring, and R4514 each independently represent the same as R461 to R471 in the formula (45).
In the formula (45), it is preferable that at least one of R462, R464, R465, R470 or R471 (preferably, at least one of R462, R465 or R470, more preferably R462) is a group forming no cyclic structure.
(i) A substituent, if present, for a cyclic structure formed by Rn and Rn+1 in the formula (45),
(ii) R461 to R471 forming no cyclic structure in the formula (45), and (iii) R4501 to R4514 and R4515 to R4525 in the formulae (451) to (460) are preferably each independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —N(R906)(R907), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, and groups represented by formulae (461) to (464).
In the formulae (461) to (464):
Rd are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
X46 is C(R801)(R802), NR803, an oxygen atom or a sulfur atom;
R801, R802, and R803 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms;
when a plurality of R801 are present, the plurality of R801 are mutually the same or different;
when a plurality of R802 are present, the plurality of R802 are mutually the same or different;
when a plurality of R803 are present, the plurality of R803 are mutually the same or different;
p1 is 5;
p2 is 4;
p3 is 3;
p4 is 7; and
* in the formulae (461) to (464) each independently represent a bonding position to a cyclic structure.
In the third and fourth compounds, R901 to R907 represent the same as those as described above.
In an exemplary embodiment, the compound represented by the formula (45) is represented by one of formulae (45-1) to (45-6) below.
In the formulae (45-1) to (45-6):
rings d to i are each independently a substituted or unsubstituted monocyclic ring or a substituted or unsubstituted fused ring; and
R461 to R471 each independently represent the same as R461 to R471 in the formula (45).
In an exemplary embodiment, the compound represented by the formula (45) is represented by one of formulae (45-7) to (45-12) below.
In the formulae (45-7) to (45-12):
rings d to f, k and j are each independently a substituted or unsubstituted monocyclic ring or a substituted or unsubstituted fused ring; and
R461 to R471 each independently represent the same as R461 to R471 in the formula (45).
In an exemplary embodiment, the compound represented by the formula (45) is represented by one of formulae (45-13) to (45-21) below.
In the formulae (45-13) to (45-21):
rings d to k are each independently a substituted or unsubstituted monocyclic ring or a substituted or unsubstituted fused ring; and
R461 to R471 each independently represent the same as R461 to R471 in the formula (45).
When the ring g or the ring h further has a substituent, examples of the substituent include a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a group represented by the formula (461), a group represented by the formula (463), and a group represented by the formula (464).
In an exemplary embodiment, the compound represented by the formula (45) is represented by one of formulae (45-22) to (45-25) below.
In the formulae (45-22) to (45-25):
X46 and X47 are each independently C(R801)(R802), NR803, an oxygen atom or a sulfur atom;
R461 to R471 and R481 to R488 each independently represent the same as R461 to R471 of the formula (45);
R801, R802, and R803 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms;
when a plurality of R801 are present, the plurality of R801 are mutually the same or different;
when a plurality of R802 are present, the plurality of R802 are mutually the same or different; and
when a plurality of R803 are present, the plurality of R803 are mutually the same or different.
In an exemplary embodiment, the compound represented by the formula (45) is represented by a formula (45-26) below.
In the formula (45-26):
X46 is C(R801)(R802), NR803, an oxygen atom or a sulfur atom;
R463, R464, R467, R468, R471, and R481 to R492 each independently represent the same as R461 to R471 in the formula (45);
R801, R802, and R803 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms;
when a plurality of R801 are present, the plurality of R801 are mutually the same or different;
when a plurality of R802 are present, the plurality of R802 are mutually the same or different; and
when a plurality of R803 are present, the plurality of R803 are mutually the same or different.
Specific examples of the compound represented by the formula (4) include compounds shown below. In the specific examples below, Ph represents a phenyl group, and D represents a deuterium atom.
The compound represented by the formula (5) will be described. The compound represented by the formula (5) corresponds to a compound represented by the formula (41-3).
In the formula (5):
at least one combination of adjacent two or more of R501 to R507 and R511 to R517 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R501 to R507 and R511 to R517 forming neither the monocyclic ring nor the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
R521 and R522 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
“A combination of adjacent two or more of R501 to R507 and R511 to R517” refers to, for instance, a combination of R501 and R502, a combination of R502 and R503, a combination of R503 and R504, a combination of R505 and R506, a combination of R506 and R507, and a combination of R501, R502, and R503.
In an exemplary embodiment, at least one, preferably two of R501 to R507 and R511 to R517 are groups represented by —N(R906)(R907).
In an exemplary embodiment, R501 to R507 and R511 to R517 are each independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, the compound represented by the formula (5) is a compound represented by a formula (52) below.
In the formula (52):
at least one combination of adjacent two or more of R531 to R534 and R541 to R544 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R531 to R534, R541 to R544 forming neither the monocyclic ring nor the fused ring, and R551 and R552 are each independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
R561 to R564 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, the compound represented by the formula (5) is a compound represented by a formula (53) below.
In the formula (53), R551, R552 and R561 to R564 each independently represent the same as R551, R552 and R561 to R564 in the formula (52).
In an exemplary embodiment, R561 to R564 in the formulae (52) and (53) are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms (preferably a phenyl group).
In an exemplary embodiment, R521 and R522 in the formula (5) and R551 and R552 in the formulae (52) and (53) are each a hydrogen atom.
In an exemplary embodiment, a substituent for the “substituted or unsubstituted” group in the formulae (5), (52) and (53) is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
Specific examples of the compound represented by the formula (5) include compounds shown below.
The compound represented by the formula (6) will be described.
In the formula (6):
a ring, b ring and c ring are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms;
R601 and R602 are each independently bonded to the a ring, b ring or c ring to form a substituted or unsubstituted heterocycle, or not bonded thereto to form no substituted or unsubstituted heterocycle; and
R601 and R602 not forming the substituted or unsubstituted heterocycle are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
The a ring, b ring and c ring are each a ring (a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms) fused with a fused bicyclic structure formed of a boron atom and two nitrogen atoms at the center of the formula (6).
The “aromatic hydrocarbon ring” for the a, b, and c rings has the same structure as a compound formed by introducing a hydrogen atom to the “aryl group” described above.
Ring atoms of the “aromatic hydrocarbon ring” for the a ring include three carbon atoms on the fused bicyclic structure at the center of the formula (6).
Ring atoms of the “aromatic hydrocarbon ring” for the b ring and the c ring include two carbon atoms on the fused bicyclic structure at the center of the formula (6).
Specific examples of the “substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms” include a compound formed by introducing a hydrogen atom to the “aryl group” described in the specific example group G1.
The “heterocycle” for the a, b, and c rings has the same structure as a compound formed by introducing a hydrogen atom to the “heterocyclic group” described above.
Ring atoms of the “heterocycle” for the a ring include three carbon atoms on the fused bicyclic structure at the center of the formula (6). Ring atoms of the “heterocycle” for the b ring and c ring include two carbon atoms on the fused bicyclic structure at the center of the formula (6). Specific examples of the “substituted or unsubstituted heterocycle having 5 to 50 ring atoms” include a compound formed by introducing a hydrogen atom to the “heterocyclic group” described in the specific example group G2.
R601 and R602 are optionally each independently bonded with the a ring, b ring, or c ring to form a substituted or unsubstituted heterocycle. The “heterocycle” in this arrangement includes a nitrogen atom on the fused bicyclic structure at the center of the formula (6). The heterocycle in the above arrangement optionally includes a hetero atom other than the nitrogen atom. R601 and R602 bonded with the a ring, b ring, or c ring specifically means that atoms forming R601 and R602 are bonded with atoms forming the a ring, b ring, or c ring. For instance, R601 may be bonded with the a ring to form a bicyclic (or tri-or-more cyclic) fused nitrogen-containing heterocycle, in which the ring including R601 and the a ring are fused. Specific examples of the nitrogen-containing heterocycle include a compound corresponding to the nitrogen-containing bi(or-more)cyclic fused heterocyclic group in the specific example group G2.
The same applies to R901 bonded with the b ring, R602 bonded with the a ring, and R602 bonded with the c ring.
In an exemplary embodiment, the a ring, b ring and c ring in the formula (6) are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms.
In an exemplary embodiment, the a ring, b ring and c ring in the formula (6) are each independently a substituted or unsubstituted benzene ring or a substituted or unsubstituted naphthalene ring.
In an exemplary embodiment, R601 and R602 in the formula (6) are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, preferably a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, the compound represented by the formula (6) is a compound represented by a formula (62) below.
In the formula (62):
R601A is bonded with at least one of R611 or R621 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R602A is bonded with at least one of R613 or R614 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R601A and R602A not forming the substituted or unsubstituted heterocycle are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
at least one combination of adjacent two or more of R611 to R621 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R611 to R621 not forming the substituted or unsubstituted heterocycle, not forming the monocyclic ring, and not forming the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
R601A and R602A in the formula (62) are groups corresponding to R601 and R602 in the formula (6), respectively.
For instance, R601A and R611 are optionally bonded with each other to form a bicyclic (or tri-or-more cyclic) fused nitrogen-containing heterocycle, in which the ring including R601A and R611 and a benzene ring corresponding to the a ring are fused. Specific examples of the nitrogen-containing heterocycle include a compound corresponding to the nitrogen-containing bi(or-more)cyclic fused heterocyclic group in the specific example group G2. The same applies to R601A bonded with R621, R602A bonded with R613, and R602A bonded with R614.
At least one combination of adjacent two or more of R611 to R621 may be mutually bonded to form a substituted or unsubstituted monocyclic ring, or mutually bonded to form a substituted or unsubstituted fused ring.
For instance, R611 and R612 are optionally mutually bonded to form a structure in which a benzene ring, indole ring, pyrrole ring, benzofuran ring, benzothiophene ring or the like is fused to the six-membered ring bonded with R611 and R612, the resultant fused ring forming a naphthalene ring, carbazole ring, indole ring, dibenzofuran ring, or dibenzothiophene ring, respectively.
In an exemplary embodiment, R611 to R621 not contributing to ring formation are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, R611 to R621 not contributing to ring formation are each independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, R611 to R621 not contributing to ring formation are each independently a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, R611 to R621 not contributing to ring formation are each independently a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, and at least one of R611 to R621 is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, the compound represented by the formula (62) is a compound represented by a formula (63) below.
In the formula (63):
R631 is bonded with R646 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R633 is bonded with R647 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R634 is bonded with R651 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R641 is bonded with R642 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
at least one combination of adjacent two or more of R631 to R651 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R631 to R651 not forming the substituted or unsubstituted heterocycle, not forming the monocyclic ring, and not forming the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
R631 are optionally bonded with R646 to form a substituted or unsubstituted heterocycle. For instance, R631 and R646 are optionally bonded with each other to form a tri-or-more cyclic fused nitrogen-containing heterocycle, in which a benzene ring bonded with R646, a ring including a nitrogen atom, and a benzene ring corresponding to the a ring are fused. Specific examples of the nitrogen-containing heterocycle include a compound corresponding to the nitrogen-containing tri(-or-more)cyclic fused heterocyclic group in the specific example group G2. The same applies to R633 bonded with R647, R634 bonded with R651, and R641 bonded with R642.
In an exemplary embodiment, R631 to R651 not contributing to ring formation are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, R631 to R651 not contributing to ring formation are each independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, R631 to R651 not contributing to ring formation are each independently a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, R631 to R651 not contributing to ring formation are each independently a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, and at least one of R631 to R651 is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, the compound represented by the formula (63) is a compound represented by a formula (63A) below.
In the formula (63A):
R661 is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, and
R662 to R665 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, R661 to R665 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, R661 to R665 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, the compound represented by the formula (63) is a compound represented by a formula (63B) below.
In the formula (63B):
R671 and R672 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —N(R906)(R907), or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms; and
R673 to R675 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —N(R906)(R907), or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, the compound represented by the formula (63) is a compound represented by a formula (63B′) below.
In the formula (63B′), R672 to R675 each independently represent the same as R672 to R675 in the formula (63B).
In an exemplary embodiment, at least one of R671 to R675 is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —N(R906)(R907), or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment: R672 is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a group represented by —N(R906)(R907), or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, R671 and R673 to R675 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a group represented by —N(R906)(R907), or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, the compound represented by the formula (63) is a compound represented by a formula (63C) below.
In the formula (63C): R681 and R682 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
R683 to R686 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, the compound represented by the formula (63) is a compound represented by a formula (63C′) below.
In the formula (63C′), R683 to R686 each independently represent the same as R683 to R686 in the formula (63C).
In an exemplary embodiment, R681 to R686 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, R681 to R686 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
The compound represented by the formula (6) is producible by initially bonding the a ring, b ring and c ring with linking groups (a group including N—R601 and a group including N—R602) to form an intermediate (first reaction), and bonding the a ring, b ring and c ring with a linking group (a group including a boron atom) to form a final product (second reaction). In the first reaction, an amination reaction (e.g. Buchwald-Hartwig reaction) is applicable. In the second reaction, Tandem Hetero-Friedel-Crafts Reactions or the like is applicable.
Specific examples of the compound represented by the formula (6) are shown below. It should however be noted that these specific examples are merely exemplary and do not limit the compound represented by the formula (6).
The compound represented by the formula (7) will be described below.
In the formula (7):
r ring is a ring represented by the formula (72) or the formula (73), the r ring being fused with adjacent ring(s) at any position(s);
q ring and s ring are each independently a ring represented by the formula (74) and fused with adjacent ring(s) at any position(s);
p ring and t ring are each independently a structure represented by the formula (75) or the formula (76) and fused with adjacent ring(s) at any position(s);
X7 is an oxygen atom, a sulfur atom, or NR702;
when a plurality of R701 are present, adjacent ones of the plurality of R701 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R701 and R702 forming neither the monocyclic ring nor the fused ring are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
Ar701 and Ar702 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
L701 is a substituted or unsubstituted alkylene group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenylene group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynylene group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 50 ring carbon atoms, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms;
m1 is 0, 1, or 2;
m2 is 0, 1, 2, 3, or 4;
m3 is each independently 0, 1, 2, or 3;
m4 is each independently 0, 1, 2, 3, 4, or 5;
when a plurality of R701 are present, the plurality of R701 are mutually the same or different;
when a plurality of X7 are present, the plurality of X7 are mutually the same or different;
when a plurality of R702 are present, the plurality of R702 are mutually the same or different;
when a plurality of Ar701 are present, the plurality of Ar701 are mutually the same or different;
when a plurality of Ar702 are present, the plurality of Ar702 are mutually the same or different; and
when a plurality of L701 are present, the plurality of L701 are mutually the same or different.
In the formula (7), each of the p ring, q ring, r ring, s ring, and t ring is fused with an adjacent ring(s) sharing two carbon atoms. The fused position and orientation are not limited but may be defined as required.
In an exemplary embodiment, in the formula (72) or the formula (73) representing the r ring, m1=0 or m2=0 is satisfied.
In an exemplary embodiment, the compound represented by the formula (7) is represented by any one of formulae (71-1) to (71-6) below.
In the formulae (71-1) to (71-6), R701, X7, Ar701, Ar702, L701, m1, and m3 respectively represent the same as R701, X7, Ar701, Ar702, L701, m1, and m3 in the formula (7).
In an exemplary embodiment, the compound represented by the formula (7) is represented by any one of formulae (71-11) to (71-13) below.
In the formulae (71-11) to (71-13), R701, X7, Ar701, Ar702, L-701, m1, m3 and m4 respectively represent the same as R701, X7, Ar701, Ar702, L-701, m1, m3 and m4 in the formula (7).
In an exemplary embodiment, the compound represented by the formula (7) is represented by any one of formulae (71-21) to (71-25) below.
In the formulae (71-21) to (71-25), R701, X7, Ar701, Ar702, L701, m1, and m4 respectively represent the same as R701, X7, Ar701, Ar702, L701, m1, and m4 in the formula (7).
In an exemplary embodiment, the compound represented by the formula (7) is represented by any one of formulae (71-31) to (71-33) below.
In the formulae (71-31) to (71-33), R701, X7, Ar701, Ar702, L701, and m2 to m4 respectively represent the same as R701, X7, Ar701, Ar702, L701, and m2 to m4 in the formula (7).
In an exemplary embodiment, Ar701 and Ar702 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, one of Ar701 and Ar702 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, and the other of Ar701 and Ar702 is a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
Specific examples of the compound represented by the formula (7) include compounds shown below.
The compound represented by the formula (8) will be described below.
In the formula (8):
at least one combination of R801 and R802, R802 and R803, or R803 and R804 are mutually bonded to form a divalent group represented by a formula (82) below; and
at least one combination of R805 and R806, R806 and R07, or R807 and R808 are mutually bonded to form a divalent group represented by a formula (83) below.
At least one of R801 to R804 not forming the divalent group represented by the formula (82) or R11 to R814 is a monovalent group represented by a formula (84) below;
at least one of R805 to R808 not forming the divalent group represented by the formula (83) or R821 to R824 is a monovalent group represented by a formula (84) below;
X8 is an oxygen atom, a sulfur atom, or NR809; and
R801 to R808 not forming the divalent group represented by the formula (82) or (83) and not being the monovalent group represented by the formula (84), R811 to R814 and R821 to R824 not being the monovalent group represented by the formula (84), and R809 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the formula (84):
Ar801 and Ar802 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
L801 to L803 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms, or a divalent linking group formed by bonding two, three or four groups selected from the group consisting of a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms and a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms; and
* in the formula (84) represents a bonding position to a cyclic structure represented by the formula (8) or a bonding position to a group represented by the formula (82) or (83).
In the formula (8), the positions for the divalent group represented by the formula (82) and the divalent group represented by the formula (83) to be formed are not specifically limited but the divalent groups may be formed at any possible positions on R801 to R808.
In an exemplary embodiment, the compound represented by the formula (8) is represented by any one of formulae (81-1) to (81-6) below.
In the formulae (81-1) to (81-6):
X8 represents the same as X8 in the formula (8);
at least two of R801 to R824 are each a monovalent group represented by the formula (84); and
R801 to R824 that are not the monovalent group represented by the formula (84) are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, the compound represented by the formula (8) is represented by any one of formulae (81-7) to (81-18) below.
In the formulae (81-7) to (81-18):
X8 represents the same as X8 in the formula (8);
* is a single bond bonded to a monovalent group represented by the formula (84);
R801 to R824 each independently represent the same as R801 to R824 in the formulae (81-1) to (81-6) that are not the monovalent group represented by the formula (84).
R801 to R808 not forming the divalent group represented by the formula (82) or (83) and not being the monovalent group represented by the formula (84), and R811 to R814 and R821 to R824 not being the monovalent group represented by the formula (84) are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
The monovalent group represented by the formula (84) is preferably represented by a formula (85) or (86) below.
In the formula (85):
R831 to R840 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
* in the formula (85) represents the same as * in the formula (84).
In the formula (86):
Ar801, L801, and L803 represent the same as Ar801, L801, and L803 in the formula (84); and
HAr801 is a structure represented by a formula (87) below.
In the formula (87):
X81 is an oxygen atom or a sulfur atom;
one of R841 to R848 is a single bond with L803; and
R841 to R848 not being the single bond are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
Specific examples of the compound represented by the formula (8) include compounds shown below as well as the compounds disclosed in WO 2014/104144.
The compound represented by the formula (9) will be described below.
In the formula (9):
A91 ring and A92 ring are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms; and
at least one of A91 ring or A92 ring is bonded with * in a structure represented by a formula (92) below.
In the formula (92):
A93 ring is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms;
X9 is NR93, C(R94)(R95), Si(R96)(R97), Ge(R98)(R99), an oxygen atom, a sulfur atom, or a selenium atom;
R91 and R92 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded; and
R91 and R92 not forming the monocyclic ring and not forming the fused ring, and R93 to R99 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
At least one ring selected from the group consisting of A91 ring and A92 ring is bonded to a bond * of a structure represented by the formula (92). In other words, the ring-forming carbon atoms of the aromatic hydrocarbon ring or the ring atoms of the heterocycle of the A91 ring in an exemplary embodiment are bonded to the bonds * in a structure represented by the formula (92). Further, the ring-forming carbon atoms of the aromatic hydrocarbon ring or the ring atoms of the heterocycle of the A92 ring in an exemplary embodiment are bonded to the bonds * in a structure represented by the formula (92).
In an exemplary embodiment, a group represented by a formula (93) below is bonded to one or both of the A91 ring and A92 ring.
In the formula (93):
Ar91 and Ar92 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
L91 to L93 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms, a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms, or a divalent linking group formed by bonding two, three or four groups selected from the group consisting of a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms and a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms; and
* in the formula (93) represents a bonding position to one of A91 ring and A92 ring.
In an exemplary embodiment, in addition to the A91 ring, the ring-forming carbon atoms of the aromatic hydrocarbon ring or the ring atoms of the heterocycle of the A92 ring are bonded to * in a structure represented by the formula (92). In this case, the structures represented by the formula (92) may be mutually the same or different.
In an exemplary embodiment, R91 and R92 are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, R91 and R92 are mutually bonded to form a fluorene structure.
In an exemplary embodiment, the rings A91 and A92 are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, example of which is a substituted or unsubstituted benzene ring.
In an exemplary embodiment, the ring A93 is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, example of which is a substituted or unsubstituted benzene ring.
In an exemplary embodiment, X9 is an oxygen atom or a sulfur atom.
Specific examples of the compound represented by the formula (9) include compounds shown below.
The compound represented by the formula (10) will be described below.
In the formula (10):
Ax1 ring is a ring represented by the formula (10a) and fused with adjacent ring(s) at any position(s);
Ax2 ring is a ring represented by the formula (10b) and fused with adjacent ring(s) at any position(s);
two * in the formula (10b) are bonded to Ax3 ring at any position(s);
XA and XB are each independently C(R1003)(R1004), Si(R1005)(R1006), an oxygen atom or a sulfur atom;
Ax3 ring is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocycle having 5 to 50 ring atoms;
Ar1001 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
R1001 to R1006 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
mx1 is 3, mx2 is 2;
a plurality of R1001 are mutually the same or different;
a plurality of R1002 are mutually the same or different;
ax is 0, 1, or 2;
when ax is 0 or 1, the structures enclosed by brackets indicated by “3-ax” are mutually the same or different; and
when ax is 2, a plurality of Ar1001 are mutually the same or different.
In an exemplary embodiment, Ar1001 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
In an exemplary embodiment, Ax3 ring is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms, example of which is a substituted or unsubstituted benzene ring, a substituted or unsubstituted naphthalene ring, or a substituted or unsubstituted anthracene ring.
In an exemplary embodiment, R1003 and R1004 are each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, ax is 1.
Specific examples of the compound represented by the formula (10) include compounds shown below.
In an exemplary embodiment, the emitting layer contains, as at least one of the third compound or the fourth compound, at least one compound selected from the group consisting of a compound represented by the formula (4), a compound represented by the formula (5), a compound represented by the formula (7), a compound represented by the formula (8), a compound represented by the formula (9) and a compound represented by a formula (63a) below.
In the formula (63a):
R631 is bonded with R646 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R633 is bonded with R647 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R634 is bonded with R651 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R641 is bonded with R642 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
at least one combination of adjacent two or more of R631 to R651 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R631 to R651 not forming the substituted or unsubstituted heterocycle, not forming the monocyclic ring, and not forming the fused ring are each independently a hydrogen atom, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; and
at least one of R631 to R651 not forming the substituted or unsubstituted heterocycle, not forming the monocyclic ring and not forming the fused ring are a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R906)(R907), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, the compound represented by the formula (4) is a compound represented by the formula (41-3), the formula (41-4), or the formula (41-5), the A1 ring in the formula (41-5) being a substituted or unsubstituted fused aromatic hydrocarbon ring having 10 to 50 ring carbon atoms, or a substituted or unsubstituted fused heterocycle having 8 to 50 ring atoms.
In an exemplary embodiment, the substituted or unsubstituted fused aromatic hydrocarbon ring having 10 to 50 ring carbon atoms in the formulae (41-3), (41-4) and (41-5) is a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted anthracene ring, or a substituted or unsubstituted fluorene ring; and
the substituted or unsubstituted fused heterocycle having 8 to 50 ring atoms is a substituted or unsubstituted dibenzofuran ring, a substituted or unsubstituted carbazole ring, or a substituted or unsubstituted dibenzothiophene ring.
In an exemplary embodiment, the substituted or unsubstituted fused aromatic hydrocarbon ring having 10 to 50 ring carbon atoms in the formula (41-3), (41-4) or (41-5) is a substituted or unsubstituted naphthalene ring, or a substituted or unsubstituted fluorene ring; and the substituted or unsubstituted fused heterocycle having 8 to 50 ring atoms is a substituted or unsubstituted dibenzofuran ring, a substituted or unsubstituted carbazole ring, or a substituted or unsubstituted dibenzothiophene ring.
In an exemplary embodiment, the compound represented by the formula (4) is selected from the group consisting of a compound represented by a formula (461) below, a compound represented by a formula (462) below, a compound represented by a formula (463) below, a compound represented by a formula (464) below, a compound represented by a formula (465) below, a compound represented by a formula (466) below and a compound represented by a formula (467) below.
In the formulae (461) to (467):
at least one combination of adjacent two or more of R421 to R427, R431 to R436, R440 to R448, and R451 to R454 are mutually bonded to form a substituted or unsubstituted monocyclic ring, mutually bonded to form a substituted or unsubstituted fused ring, or not mutually bonded;
R437R438, and R421 to R427, R431 to R43, R440 to R448, and R451 to R454 forming neither the monocyclic ring nor the fused ring are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a group represented by —Si(R901)(R902)(R903), a group represented by —O—(R904), a group represented by —S—(R905), a group represented by —N(R900)(R900), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms;
X4 is an oxygen atom, NR801, or C(R802)(R803);
R801, R802, and R803 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms;
when a plurality of R801 are present, the plurality of R801 are mutually the same or different;
when a plurality of R802 are present, the plurality of R802 are mutually the same or different; and
when a plurality of R803 are present, the plurality of R803 are mutually the same or different.
In an exemplary embodiment, R421 to R427 and R440 to R448 are each independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, R421 to R427 and R440 to R447 are each independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, and a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
In an exemplary embodiment, the compound represented by the formula (41-3) is a compound represented by a formula (41-3-1) below.
In the formula (41-3-1), R423, R425, R426, R442, R444 and R445 each independently represent the same as R423, R425, R426, R442, R444 and R445 in the formula (41-3).
In an exemplary embodiment, the compound represented by the formula (41-3) is a compound represented by a formula (41-3-2) below.
In the formula (41-3-2), R421 to R427 and R440 to R448 each independently represent the same as R421 to R427 and R440 to R448 in the formula (41-3); and
at least one of R421 to R427 or R440 to R446 is a group represented by —N(R906)(R907).
In an exemplary embodiment, two of R421 to R427 and R440 to R446 in the formula (41-3-2) are each a group represented by —N(R906)(R907).
In an exemplary embodiment, the compound represented by the formula (41-3-2) is a compound represented by a formula (41-3-3) below.
In the formula (41-3-3), R421 to R424, R440 to R443, R447, and R448 each independently represent the same as R421 to R424, R440 to R443, R447, and R448 in the formula (41-3); and
RA, RB, RC, and RD are each independently a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
In an exemplary embodiment, the compound represented by the formula (41-3-3) is a compound represented by a formula (41-3-4) below.
In the formula (41-3-4), R447, R448, RA, RB, RC and RD each independently represent the same as R447, R448, RA, RB, RC and RD in the formula (41-3-3).
In an exemplary embodiment, RA, RB, RC, and RD are each independently a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms.
In an exemplary embodiment, RA, RB, RC, and RD are each independently a substituted or unsubstituted phenyl group.
In an exemplary embodiment, R447 and R448 are each a hydrogen atom.
In an exemplary embodiment, a substituent for the “substituted or unsubstituted” group in each of the formulae is an unsubstituted alkyl group having 1 to 50 carbon atoms, an unsubstituted alkenyl group having 2 to 50 carbon atoms, an unsubstituted alkynyl group having 2 to 50 carbon atoms, an unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, —Si(R901a)(R902a)(R903a), —O—(R904a), —S—(R905a), —N(R906a)(R907a), a halogen atom, a cyano group, a nitro group, an unsubstituted aryl group having 6 to 50 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 50 ring atoms; R901a to R907a are each independently a hydrogen atom, an unsubstituted alkyl group having 1 to 50 carbon atoms, an unsubstituted aryl group having 6 to 50 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 50 ring atoms; when two or more R901a are present, the two or more R901a are mutually the same or different; when two or more R902a are present, the two or more R902a are mutually the same or different; when two or more R903a are present, the two or more R903a are mutually the same or different; when two or more R904a are present, the two or more R904a are mutually the same or different; when two or more R905a are present, the two or more R905a are mutually the same or different; when two or more R906a are present, the two or more R906a are mutually the same or different; and when two or more R907a are present, the two or more R907a are mutually the same or different.
In an exemplary embodiment, a substituent for the “substituted or unsubstituted” group in each of the formulae is an unsubstituted alkyl group having 1 to 50 carbon atoms, an unsubstituted aryl group having 6 to 50 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 50 ring atoms.
In an exemplary embodiment, a substituent for the “substituted or unsubstituted” group in each of the formulae is an unsubstituted alkyl group having 1 to 18 carbon atoms, an unsubstituted aryl group having 6 to 18 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 18 ring atoms.
In the organic EL device according to the exemplary embodiment, the two or more emitting units preferably include at least one phosphorescent emitting unit. In the organic EL device according to the exemplary embodiment, the anode side emitting unit may be a phosphorescent emitting unit and/or the cathode side emitting unit may be a phosphorescent emitting unit. The phosphorescent emitting unit preferably contains a phosphorescent compound that exhibits phosphorescence.
The phosphorescent emitting unit preferably includes a phosphorescent emitting layer containing a phosphorescent compound.
The phosphorescent compound is preferably a metal complex The metal complex as a phosphorescent compound is preferably an iridium complex, a copper complex, a platinum complex, an osmium complex, or a gold complex.
The phosphorescent emitting unit preferably includes at least one phosphorescent layer containing a phosphorescent compound. The phosphorescent emitting unit may include two or more phosphorescent layers. When the phosphorescent emitting unit includes two or more phosphorescent layers, the phosphorescent layers may be in direct contact with each other or may not be in contact with each other.
The phosphorescent emitting unit preferably exhibits phosphorescence having a maximum peak wavelength of 500 nm or more. The phosphorescent emitting unit preferably includes a phosphorescent emitting layer that exhibits phosphorescence having a maximum peak wavelength of 500 nm or more.
The phosphorescent emitting unit preferably includes at least one of a red phosphorescent emitting layer or a green phosphorescent emitting layer. More preferably, the phosphorescent emitting unit includes both of the red phosphorescent emitting layer and the green phosphorescent emitting layer. The red phosphorescent emitting layer preferably contains a red phosphorescent compound that exhibits phosphorescence having a maximum peak wavelength in a range from 600 nm to 660 nm. The green phosphorescent emitting layer preferably contains a green phosphorescent compound that exhibits phosphorescence having a maximum peak wavelength in a range from 500 nm to 560 nm.
When the emitting compound in the emitting layer is a phosphorescent compound, the maximum peak wavelength of emission of the phosphorescent compound can be measured by a method described in Examples below. Herein, the maximum peak wavelength of phosphorescence is occasionally referred to as a maximum phosphorescence peak wavelength (PH-peak).
The organic EL device according to the exemplary embodiment also preferably includes one fluorescent emitting unit and one phosphorescent emitting unit. In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit is a fluorescent emitting unit and the cathode side emitting unit is a phosphorescent emitting unit. In an arrangement of the organic EL device according to the exemplary embodiment, the anode side emitting unit is a phosphorescent emitting unit and the cathode side emitting unit is a fluorescent emitting unit.
Examples of the device arrangement of the organic EL device including the anode side emitting unit and the phosphorescent emitting unit as a plurality of emitting units include (TND3) and (TND4) below.
(TND3) anode/second organic layer/first organic layer/anode side emitting unit (first emitting unit)/charge generating unit/second emitting unit (phosphorescent emitting unit)/cathode
(TND4) anode/second organic layer/first organic layer/anode side emitting unit (first emitting unit)/first charge generating unit/second emitting unit (phosphorescent emitting unit)/second charge generating unit/third emitting unit/cathode
The number of the emitting units and the charge generating units is not limited to the above examples of (TND3) and (TND4).
It should be noted that the organic EL device according to the exemplary embodiment may not include a phosphorescent emitting unit. In the organic EL device according to the exemplary embodiment, all the emitting units may be each a fluorescent emitting unit.
It is preferable that each emitting layer in the emitting unit independently contains a host material and an emitting compound.
Examples of the emitting compound include a fluorescent compound exhibiting fluorescence and a phosphorescent compound exhibiting phosphorescence. The fluorescent compound is a compound capable of emitting from a singlet state. The phosphorescent compound is a compound capable of emitting from a triplet state. One of the emitting compounds may be used alone, or two or more thereof may be used in combination.
The emitting compound is not particularly limited and the above-described emitting compounds and known emitting compounds are usable.
Examples of a blue fluorescent compound include a pyrene derivative, a styrylamine derivative, a chrysene derivative, a fluoranthene derivative, a fluorene derivative, a monoamine derivative, a diamine derivative, and a triarylamine derivative.
Examples of a red fluorescent compound include a tetracene derivative and a diamine derivative.
Examples of a green fluorescent compound include an aromatic amine derivative.
Examples of a yellow fluorescent compound include an anthracene derivative and a fluoranthene derivative.
Examples of a blue phosphorescent compound include metal complexes such as an iridium complex, an osmium complex, and a platinum complex.
Examples of a green phosphorescent compound include an iridium complex.
Examples of a red phosphorescent compound include metal complexes such as an iridium complex, a platinum complex, a terbium complex, and a europium complex.
Examples of a yellow phosphorescent compound include an iridium complex.
The host material is not particularly limited and the above-described host materials and known host materials are usable. Examples of the known host materials include an amine derivative, an azine derivative and a fused polycyclic aromatic derivative.
Examples of the amine derivative include a monoamine compound, a diamine compound, a triamine compound, a tetramine compound, and an amine compound substituted by a carbazole group.
Examples of the azine derivative include a monoazine derivative, a diazine derivative and a triazine derivative.
The fused polycyclic aromatic derivative is preferably a fused polycyclic aromatic hydrocarbon having no heterocyclic skeleton, which is exemplified by a fused polycyclic aromatic hydrocarbon such as naphthalene, anthracene, phenanthrene, chrysene, fluoranthene, and triphenylene, or a derivative of the fused polycyclic aromatic hydrocarbon.
Except for the cases particularly described above (e.g., the film thickness of each of the first emitting layer and the second emitting layer of the anode side emitting unit), a film thickness of the emitting layer of the organic EL device according to the exemplary embodiment is preferably in a range from 5 nm to 50 nm, more preferably in a range from 7 nm to 50 nm, further preferably in a range from 10 nm to 50 nm. When the film thickness of the emitting layer is 5 nm or more, the emitting layer is easily formable and chromaticity is easily adjustable. When the film thickness of the emitting layer is 50 nm or less, a rise in the drive voltage is easily reducible.
In the organic EL device 1, the anode side emitting unit 51 and the cathode side emitting unit 52 are connected in series with the charge generating unit 70 interposed therebetween.
The organic EL device 1 includes the anode side emitting unit 51 and the cathode side emitting unit 52 as two emitting units. The anode side emitting unit 51 is occasionally referred to as the first emitting unit. The cathode side emitting unit 52 is occasionally referred to as the second emitting unit.
The invention is not limited to the arrangements of the organic EL device shown in
The organic EL device according to the exemplary embodiment may be a bottom emission type organic EL device. In addition, the organic EL device according to the exemplary embodiment may be a top emission type organic EL device.
An arrangement of an organic EL device will be further described below. It should be noted that the reference numerals will be sometimes omitted below.
The substrate is used as a support for the organic EL device. For instance, glass, quartz, plastics and the like are usable for the substrate. A flexible substrate is also usable. The flexible substrate is a bendable substrate, which is exemplified by a plastic substrate. Examples of the material for the plastic substrate include polycarbonate, polyarylate, polyethersulfone, polypropylene, polyester, polyvinyl fluoride, polyvinyl chloride, polyimide, and polyethylene naphthalate. Moreover, an inorganic vapor deposition film is also usable.
Metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a large work function (specifically, 4.0 eV or more) is preferably used as the anode formed on the substrate. Specific examples of the material include ITO (Indium Tin Oxide), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, indium oxide containing tungsten oxide and zinc oxide, and graphene. In addition, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chrome (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti), and nitrides of a metal material (e.g., titanium nitride) are usable.
The material is typically formed into a film by a sputtering method. For instance, the indium oxide-zinc oxide can be formed into a film by the sputtering method using a target in which zinc oxide in a range from 1 mass % to 10 mass % is added to indium oxide. Moreover, for instance, the indium oxide containing tungsten oxide and zinc oxide can be formed by the sputtering method using a target in which tungsten oxide in a range from 0.5 mass % to 5 mass % and zinc oxide in a range from 0.1 mass % to 1 mass % are added to indium oxide. In addition, the anode may be formed by a vacuum deposition method, a coating method, an inkjet method, a spin coating method or the like.
Among the organic layers formed on the anode, since the hole injecting layer adjacent to the anode is formed of a composite material into which holes are easily injectable irrespective of the work function of the anode, a material usable as an electrode material (e.g., metal, an alloy, an electroconductive compound, a mixture thereof, and the elements belonging to the group 1 or 2 of the periodic table) is also usable for the anode.
A material having a small work function such as elements belonging to Groups 1 and 2 in the periodic table of the elements, specifically, an alkali metal such as lithium (Li) and cesium (Cs), an alkaline earth metal such as magnesium (Mg), calcium (Ca) and strontium (Sr), alloys (e.g., MgAg and AlLi) including the alkali metal or the alkaline earth metal, a rare earth metal such as europium (Eu) and ytterbium (Yb), alloys including the rare earth metal are also usable for the anode. It should be noted that the vacuum deposition method and the sputtering method are usable for forming the anode using the alkali metal, alkaline earth metal and the alloy thereof. Further, when a silver paste is used for the anode, the coating method and the inkjet method are usable.
When the organic EL device is of a bottom emission type, the anode is preferably formed of a light-transmissive or semi-transmissive metallic material that transmits light from the emitting layer. Herein, the light-transmissive or semi-transmissive property means the property of allowing transmissivity of 50% or more (preferably 80% or more) of the light emitted from the emitting layer. The light-transmissive or semi-transmissive metallic material can be selected in use as needed from the above materials listed in the description about the anode.
When the organic EL device is of a top emission type, the anode is a reflective electrode having a reflective layer. The reflective layer is preferably formed of a metallic material having light reflectivity. Herein, the light reflectivity means the property of reflecting 50% or more (preferably 80% or more) of the light emitted from the emitting layer. The metallic material having light reflectivity can be selected in use as needed from the above materials listed in the description about the anode.
The anode may be formed only of the reflective layer, but may be a multilayer structure having the reflective layer and a conductive layer (preferably a transparent conductive layer). When the anode includes the reflective layer and the conductive layer, the conductive layer is preferably provided between the reflective layer and the second organic layer. A material of the conductive layer can be selected in use as needed from the above materials listed in the description about the anode.
It is preferable to use metal, an alloy, an electroconductive compound, a mixture thereof, or the like having a small work function (specifically, 3.8 eV or less) for the cathode. Examples of the material for the cathode include elements belonging to Groups 1 and 2 in the periodic table of the elements, specifically, the alkali metal such as lithium (Li) and cesium (Cs), the alkaline earth metal such as magnesium (Mg), calcium (Ca) and strontium (Sr), alloys (e.g., MgAg and AlLi) including the alkali metal or the alkaline earth metal, the rare earth metal such as europium (Eu) and ytterbium (Yb), and alloys including the rare earth metal.
It should be noted that the vacuum deposition method and the sputtering method are usable for forming the cathode using the alkali metal, alkaline earth metal and the alloy thereof. Further, when a silver paste is used for the cathode, the coating method and the inkjet method are usable.
By providing the electron injecting layer, various conductive materials such as Al, Ag, ITO, graphene, and indium oxide-tin oxide containing silicon or silicon oxide may be used for forming the cathode regardless of the work function. The conductive materials can be formed into a film using the sputtering method, inkjet method, spin coating method and the like.
When the organic EL device is of a bottom emission type, the cathode is a reflective electrode. The reflective layer is preferably formed of a metallic material having light reflectivity. The metallic material having light reflectivity can be selected in use as needed from the above materials listed in the description about the cathode.
When the organic EL device is of a top emission type, the cathode is preferably formed of a light-transmissive or semi-transmissive metallic material that transmits light from the emitting layer. The light-transmissive or semi-transmissive metallic material can be selected in use as needed from the above materials listed in the description about the cathode.
The top emission type organic EL device typically has a capping layer on the top of the cathode.
A capping layer may contain at least one compound selected from the group consisting of, for instance, a high polymer compound, metal oxide, metal fluoride, metal boride, silicon nitride, and silicon compound (silicon oxide or the like).
In addition, the capping layer may contain at least one compound selected from the group consisting of, for instance, an aromatic amine derivative, an anthracene derivative, a pyrene derivative, a fluorene derivative, and a dibenzofuran derivative.
Moreover, a laminate obtained by layering layers containing these substances is also usable as a capping layer.
The hole injecting layer is a layer containing a substance exhibiting a high hole injectability. Examples of the substance exhibiting a high hole injectability include molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chrome oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, and manganese oxide.
In addition, the examples of the highly hole-injectable substance further include: an aromatic amine compound, which is a low-molecule organic compound, such as 4,4′,4″-tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4′-bis(N-{4-[N′-(3-methylphenyl)-N′-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1); and dipyrazino[2,3-f:20,30-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN).
In addition, a high polymer compound (e.g., oligomer, dendrimer and polymer) is usable as the substance exhibiting a high hole injectability. Examples of the high polymer compound include poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N′-[4-(4-diphenylamino)phenyl]phenyl-N′-phenylamino}phenyl)methacrylamide](abbreviation: PTPDMA), and poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine] (abbreviation: Poly-TPD). Moreover, an acid-added high polymer compound such as poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonic acid) (PEDOT/PSS) and polyaniline/poly(styrene sulfonic acid) (PAni/PSS) are also usable.
The hole transporting layer is a layer containing a highly hole-transporting substance. An aromatic amine compound, carbazole derivative, anthracene derivative and the like are usable for the hole transporting layer. Specific examples of a material for the hole transporting layer include an aromatic amine compound such as 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (abbreviation: TPD), 4-phenyl-4′-(9-phenylfluorene-9-yl)triphenylamine (abbreviation: BAFLP), 4,4′-bis[N-(9,9-dimethylfluorene-2-yl)-N-phenylamino]biphenyl (abbreviation: DFLDPBi), 4,4′,4″-tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), and 4,4′-bis[N-(spiro-9,9′-bifluorene-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB). The above-described substances mostly have a hole mobility of 10−6 cm2/(V-s) or more.
For the hole transporting layer, a carbazole derivative such as CBP, 9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (CzPA), and 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (PCzPA) and an anthracene derivative such as t-BuDNA, DNA, and DPAnth may be used. A high polymer compound such as poly(N-vinylcarbazole) (abbreviation: PVK) and poly(4-vinyltriphenylamine) (abbreviation: PVTPA) is also usable.
However, in addition to the above substances, any substance exhibiting a higher hole transportability than an electron transportability may be used. It should be noted that the layer containing the substance exhibiting a high hole transportability may be not only a single layer but also a laminate of two or more layers formed of the above substance(s).
The electron transporting layer is a layer containing a highly electron-transporting substance. For the electron transporting layer, 1) a metal complex such as an aluminum complex, beryllium complex, and zinc complex, 2) a hetero aromatic compound such as imidazole derivative, benzimidazole derivative, azine derivative, carbazole derivative, and phenanthroline derivative, and 3) a high polymer compound are usable. Specifically, as a low-molecule organic compound, a metal complex such as Alq, tris(4-methyl-8-quinolinato)aluminum (abbreviation: Almq3), bis(10-hydroxybenzo[h]quinolinato)beryllium (abbreviation: BeBq2), BAlq, Znq, ZnPBO and ZnBTZ is usable. In addition to the metal complex, a heteroaromatic compound such as 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(ptert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviation: OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ), bathophenanthroline (abbreviation: BPhen), bathocuproine (abbreviation: BCP), and 4,4′-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviation: BzOs) is usable. Examples of the azine derivative include a pyridine derivative, a pyrimidine derivative and a triazine derivative. In the exemplary embodiment, an azine derivative or a benzimidazole compound is suitably usable. The above-described substances mostly have an electron mobility of 10−6 cm2Ns or more. It should be noted that any substance other than the above substance may be used for the electron transporting layer as long as the substance exhibits a higher electron transportability than the hole transportability. The electron transporting layer may be provided in the form of a single layer or a laminate of two or more layers of the above substance(s).
Specific examples of the compound usable for the electron transporting layer include the following compounds. It should however be noted that the invention is not limited by the specific examples of the compound.
Further, a high polymer compound is usable for the electron transporting layer. For instance, poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviation: PF-Py), poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2′-bipyridine-6,6′-diyl)] (abbreviation: PF-BPy) and the like are usable.
The electron injecting layer is a layer containing a highly electron-injectable substance. Examples of a material for the electron injecting layer include an alkali metal, alkaline earth metal and a compound thereof, examples of which include lithium (Li), cesium (Cs), calcium (Ca), lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), and lithium oxide (LiOx). In addition, the alkali metal, alkaline earth metal or the compound thereof may be added to the substance exhibiting the electron transportability in use. Specifically, for instance, magnesium (Mg) added to Alq may be used. In this case, the electrons can be more efficiently injected from the cathode.
Alternatively, the electron injecting layer may be provided by a composite material in a form of a mixture of the organic compound and the electron donor. Such a composite material exhibits excellent electron injectability and electron transportability since electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material excellent in transporting the generated electrons. Specifically, the above examples (e.g., the metal complex and the hetero aromatic compound) of the substance forming the electron transporting layer are usable. As the electron donor, any substance exhibiting electron donating property to the organic compound is usable. Specifically, the electron donor is preferably alkali metal, alkaline earth metal and rare earth metal such as lithium, cesium, magnesium, calcium, erbium and ytterbium. The electron donor is also preferably alkali metal oxide and alkaline earth metal oxide such as lithium oxide, calcium oxide, and barium oxide. Moreover, a Lewis base such as magnesium oxide is usable. Further, the organic compound such as tetrathiafulvalene (abbreviation: TTF) is usable.
Layer Formation Method(s) A method for forming each layer of the organic EL device in the exemplary embodiment is subject to no limitation except for the above particular description.
However, known methods of dry film-forming such as vacuum deposition, sputtering, plasma or ion plating and wet film-forming such as spin coating, dipping, flow coating or ink-jet are applicable.
Film Thickness A film thickness of each of the organic layers of the organic EL device in the exemplary embodiment is not limited unless otherwise specified in the above. In general, the thickness preferably ranges from several nanometers to 1 μm because excessively small film thickness is likely to cause defects (e.g. pin holes) and excessively large thickness leads to the necessity of applying high voltage and consequent reduction in efficiency.
The organic EL device according to the exemplary embodiment preferably has a color conversion portion provided on a side of the organic EL device through which light is extracted. The color conversion portion is provided on the side of the organic EL device through which light is extracted, and serves as converting the light extracted through the side through which light is extracted to desired color light. The color conversion portion is not particularly limited, but examples of the color conversion portion include a color filter and a quantum dot.
The color conversion portion is preferably disposed on an electrode (transparent electrode) that is either the anode or the cathode, which is provided on the side through which light is extracted.
Moreover, when the side through which light is extracted is close to the anode of the organic EL device, the color conversion portion may be disposed between the substrate and the anode, or may be disposed on the side of the substrate on which the anode is not provided.
In addition, when the side through which light is extracted is close to the cathode of the organic EL device, the color conversion portion may be disposed on the cathode.
For instance,
The color conversion portion is exemplified by a color filter and a material including a quantum dot.
A material for the color filter is exemplified by the following dyes only and the dyes in a solid state in which the dyes are dissolved or dispersed in a binder resin.
One or a mixture of at least two or more of a perylene pigment, lake pigment, azo pigment, quinacridone pigment, anthraquinone pigment, anthracene pigment, isoindoline pigment, isoindolinone pigment and the like are usable.
One or a mixture of at least two or more of a halogen polysubstituted phthalocyanine pigment, halogen polysubstituted copper phthalocyanine pigment, triphenylmethane basic dyes, isoindoline pigment, isoindolinone pigment and the like are usable.
One or a mixture of at least two or more of a copper phthalocyanine pigment, indanthrone pigment, indophenol pigment, cyanine pigment, dioxazine pigment and the like are usable.
The binder resin used as the material for the color filter is preferably a transparent material. For instance, a material having transmittance of 50% or more in a visible light region is preferably used.
Examples of the binder resin used as the material for the color filter include a transparent resin (polymer) such as polymethyl methacrylate, polyacrylate, polycarbonate, polyvinyl alcohol, polyvinyl pyrrolidone, hydroxyethyl cellulose, and carboxymethyl cellulose, among which one or a mixture of two or more thereof are usable.
A material for the quantum dot is exemplified by a material in which quantum dots are dispersed in a resin. CdSe, ZnSe, CdS, CdSeS/ZnS, InP, InP/ZnS, CdS/CdSe, CdS/ZnS, PbS, CdTe and the like are usable as the quantum dot.
The color filter and the material including a quantum dot may be used in combination for the color conversion portion.
The organic EL device according to the exemplary embodiment is also preferably an organic EL device for a display device. Particularly in terms of having a long lifetime, the tandem organic EL device is suitably used for a display device. Examples of the display device for which the tandem organic EL device is used include a TV, a personal computer, a tablet (occasionally referred to as a tablet computer), a Virtual Reality (VR) device, a display for a moving body (i.e., a display installed in a moving body), a display component (e.g., an organic EL panel module), a mobile phone (occasionally referred to as a cell phone) and a smartphone (occasionally referred to as a mobile phone). The tandem organic EL device can be suitably used as a medium- and large-sized panel such as a TV, a personal computer, a tablet, and a display for a moving body, for which a longer lifetime is important. The moving body with which a display device is installed is exemplified by an automobile and an aircraft.
The device of the invention, which is an improved tandem organic EL device, is suitably used for any display devices for which the tandem organic EL device can be suitably used.
The organic EL device according to the exemplary embodiment is more preferably used for a display for a tablet or a display for a VR device. In the tablet and the VR device, in order to improve immersion into the display, it is demanded to prevent a decrease in device performance (e.g., a luminous efficiency or lifetime) when the device is driven at a low current density. Thus, the organic EL device according to the exemplary embodiment is suitably used for a display for a tablet or a display for a VR device.
According to the exemplary embodiment of the invention, an organic electroluminescence device capable of preventing a decrease in device performance (e.g., a luminous efficiency or lifetime) at a low current density is provided.
An electronic device according to a second exemplary embodiment is installed with any one of the organic EL devices according to the above exemplary embodiment. Examples of the electronic device include a display device and a light-emitting unit. Examples of the display device include a TV, a personal computer, a tablet, a VR device, a display for a moving body, a display component (e.g., an organic EL panel module), a mobile phone and a smartphone. An electronic device installed with any one of the organic EL devices according to the above exemplary embodiment is preferably a tablet or a VR device. Examples of the light-emitting unit include an illuminator and a vehicle light.
The scope of the invention is not limited by the above-described exemplary embodiments but includes any modification and improvement as long as such modification and improvement are compatible with the invention.
For instance, a blocking layer may be provided adjacent to at least one of a side of the emitting layer close to the anode or a side of the emitting layer close to the cathode. The blocking layer is preferably provided in contact with the emitting layer to block at least any of holes, electrons, excitons or combinations thereof.
For instance, when the blocking layer is provided in contact with the side of the emitting layer close to the cathode, the blocking layer permits transport of electrons and blocks holes from reaching a layer provided closer to the cathode (e.g., the electron transporting layer) beyond the blocking layer. When the organic EL device includes the electron transporting layer, the blocking layer is preferably interposed between the emitting layer and the electron transporting layer.
When the blocking layer is provided in contact with the side of the emitting layer close to the anode, the blocking layer permits transport of holes and blocks electrons from reaching a layer provided closer to the anode (e.g., the hole transporting layer) beyond the blocking layer. When the organic EL device includes the hole transporting layer, the blocking layer is preferably interposed between the emitting layer and the hole transporting layer.
Alternatively, the blocking layer may be provided adjacent to the emitting layer so that excitation energy does not leak out from the emitting layer toward neighboring layer(s). The blocking layer blocks excitons generated in the emitting layer from being transferred to a layer(s) (e.g., the electron transporting layer and the hole transporting layer) closer to the electrode(s) beyond the blocking layer.
The emitting layer is preferably bonded with the blocking layer.
Specific structure, shape and the like of the components in the invention may be designed in any manner as long as an object of the invention can be achieved.
The invention will be described in further detail with reference to Examples. It should be noted that the scope of the invention is by no means limited to Examples.
Structures of compounds used for manufacturing organic EL devices in Examples 1-1, 1-2, 2-1, 2-2, 3-1, 3-2, 4-1 and 4-2 and Comparatives 1-1, 1-2, 2-1, 2-2, 3-1, 3-2, 4-1 and 4-2 are shown below.
Organic EL devices were manufactured and evaluated as follows.
A glass substrate (size: 25 mm×75 mm×1.1 mm thick, manufactured by Geomatec Co., Ltd.) having an ITO (Indium Tin Oxide) transparent electrode (anode) was ultrasonic-cleaned in isopropyl alcohol for five minutes, and then UV-ozone-cleaned for 30 minutes. A film thickness of the ITO transparent electrode was 80 nm.
The cleaned glass substrate having the transparent electrode line was attached to a substrate holder of a vacuum deposition apparatus. First, a compound HT1 (second organic material) and a compound HA1 (third organic material) were co-deposited on a surface of the glass substrate, where the transparent electrode line was provided, to cover the transparent electrode, thereby forming a 10-nm-thick second organic layer. The ratios of the compound HT1 and the compound HA1 in the second organic layer were 97 mass % and 3 mass %, respectively.
After the formation of the second organic layer, a compound HT2 (first organic material) was vapor-deposited to form a 15-nm-thick first organic layer.
In Example 1-1, an anode side emitting unit (first emitting unit) including a first emitting layer and a first electron transporting layer was formed.
After the formation of the first organic layer, a compound BH1 (first host material) and a compound BD1 (first emitting compound) were co-deposited so that the ratio of the compound BD1 was 1 mass %, thereby forming a 20-nm-thick first emitting layer.
Next, a compound ET1 was vapor-deposited on the first emitting layer to form a 5-nm-thick first electron transporting layer (also referred to as a hole blocking layer).
In Example 1-1, a charge generating unit including a first N layer and a first P layer was formed.
A compound ET2 and Li were co-deposited on the first electron transporting layer of the anode side emitting unit to form a 50-nm-thick first N layer. The concentrations of the compound ET2 and Li in the first N layer were 96 mass % and 4 mass %, respectively.
Next, the compound HT1 and the compound HA1 were co-deposited on the first N layer to form a 10-nm-thick first P layer. The concentrations of the compound HT1 and the compound HA1 in the first P layer were 97 mass % and 3 mass %, respectively.
In Example 1-1, a second emitting unit (phosphorescent emitting unit) was formed that included a first hole transporting layer, a red phosphorescent emitting layer, a green phosphorescent emitting layer, a second electron transporting layer and an electron injecting layer.
The compound HT1 was vapor-deposited on the first P layer of the charge generating unit to form a 10-nm-thick first hole transporting layer.
Next, a compound PRH1 (phophorescent host material) and a phosphorescent compound PRD1 were co-deposited on the first hole transporting layer to form a 5-nm-thick red phosphorescent emitting layer. The concentrations of the compound PRH1 and the compound PRD1 in the red phosphorescent emitting layer were 96 mass % and 4 mass %, respectively.
Next, a compound PGH1 (phophorescent host material) and a phosphorescent compound PGD1 were co-deposited on the red phosphorescent emitting layer to form a 30-nm-thick green phosphorescent emitting layer. The concentrations of the compound PGH1 and the compound PGD1 in the green phosphorescent emitting layer were 97 mass % and 3 mass %, respectively.
Next, a compound ET3 and Liq were co-deposited on the green phosphorescent emitting layer to form a 40-nm-thick second electron transporting layer. The concentrations of the compound ET3 and Liq in the second electron transporting layer were 50 mass % and 50 mass %, respectively. Liq is an abbreviation of (8-quinolinolato)lithium.
Next, ytterbium (Yb) was vapor-deposited on the second electron transporting layer to form a 1-nm-thick electron injecting layer.
Metal A1 was vapor-deposited on the electron injecting layer of the second emitting unit to form an 80-nm-thick cathode.
A bottom emission type organic EL device of Example 1-1 was manufactured as described above.
A device arrangement of the organic EL device of Example 1-1 is roughly shown as follows.
Numerals in parentheses represent a film thickness (unit: nm).
Regarding the device arrangement of the organic EL device in Example 1-1, the numerals (97%:3%) represented by percentage in the same parentheses indicate a ratio (mass %) between the compound HT1 and the compound HA1 in the second organic layer or the first P layer or a ratio (mass %) between the compound PGH1 and the compound PGD1 in the green phosphorescent emitting layer, the numerals (99%:1%) represented by percentage in the same parentheses indicate a ratio (mass %) between the compound BH1 and the compound BD1 in the first emitting layer, the numerals (96%:4%) represented by percentage in the same parentheses indicate a ratio (mass %) between the compound ET2 and Li in the first N layer or a ratio (mass %) between the compound PRH1 and the compound PRD1 in the red phosphorescent emitting layer, and the numerals (50%:50%) represented by percentage in the same parentheses indicate a ratio (mass %) between the compound ET3 and Liq in the second electron transporting layer. Similar notations apply to the description below.
An organic EL device of Example 1-2 was manufactured in the same manner as in Example 1-1 except that the compound (first organic material) used for forming the first organic layer was replaced by the compound shown in Table 1.
An organic EL device of Comparative 1-1 was manufactured in the same manner as in Example 1-1 except that a third organic layer was formed between the second organic layer and the first organic layer and the thickness of the first organic layer was changed to 5 nm. In the organic EL device of Comparative 1-1, the compound HT1 was vapor-deposited on the second organic layer to form a 10-nm-thick third organic layer, on which the first organic layer was formed.
An organic EL device of Comparative 1-2 was manufactured in the same manner as in Comparative 1-1 except that the compound (first organic material) used for forming the first organic layer was replaced by the compound shown in Table 1.
A 100-nm-thick APC (Ag—Pd—Cu) layer (reflective layer), which was silver alloy layer, and a 10-nm-thick indium oxide-zinc oxide (IZO: registered trademark) layer (transparent conductive layer) were sequentially formed by sputtering on a glass substrate (25 mm×75 mm×0.7 mm thick) to be a substrate for manufacturing a device. A conductive material layer made of the APC layer and the IZO layer was thus obtained.
Subsequently, the conductive material layer was patterned by etching using a resist pattern as a mask using a normal lithography technique to form a lower electrode (anode).
Next, the compound HT1 (second organic material) and the compound HA1 (third organic material) were co-deposited on the lower electrode (anode) to form a 7-nm-thick second organic layer. The ratios of the compound HT1 and the compound HA1 in the second organic layer were 97 mass % and 3 mass %, respectively.
After the formation of the second organic layer, the compound HT2 (first organic material) was vapor-deposited to form a 15-nm-thick first organic layer.
In Example 2-1, an anode side emitting unit (first emitting unit) including a first emitting layer and a first electron transporting layer was formed.
After the formation of the first organic layer, the compound BH1 (first host material) and the compound BD1 (first emitting compound) were co-deposited so that the ratio of the compound BD1 was 1 mass %, thereby forming a 20-nm-thick first emitting layer.
Next, the compound ET1 was vapor-deposited on the first emitting layer to form a 5-nm-thick first electron transporting layer (also referred to as a hole blocking layer).
In Example 2-1, a charge generating unit including a first N layer and a first P layer was formed.
The compound ET2 and Li were co-deposited on the first electron transporting layer of the anode side emitting unit to form a 70-nm-thick first N layer.
The concentrations of the compound ET2 and Li in the first N layer were 96 mass % and 4 mass %, respectively.
Next, the compound HT1 and the compound HA1 were co-deposited on the first N layer to form a 10-nm-thick first P layer. The concentrations of the compound HT1 and the compound HA1 in the first P layer were 90 mass % and 10 mass %, respectively.
In Example 2-1, a second emitting unit was formed that included a first hole transporting layer, a second hole transporting layer, an emitting layer, a second electron transporting layer, a third electron transporting layer and an electron injecting layer.
The compound HT1 was vapor-deposited on the first P layer of the charge generating unit to form a 10-nm-thick first hole transporting layer.
Next, the compound HT2 was vapor-deposited on the first hole transporting layer to form a 5-nm-thick second hole transporting layer (also referred to as an electron blocking layer).
Next, the compound BH1 and the compound BD1 were co-deposited on the second hole transporting layer so that the ratio of the compound BD1 was 1 mass %, thereby forming a 20-nm-thick emitting layer (UT2-EM).
Next, the compound ET1 was vapor-deposited on the emitting layer (UT2-EM) to form a 5-nm-thick second electron transporting layer (also referred to as a hole blocking layer).
Next, the compound ET3 and Liq were co-deposited on the second electron transporting layer to form a 25-nm-thick third electron transporting layer. The concentrations of the compound ET3 and Liq in the third electron transporting layer were 50 mass % and 50 mass %, respectively.
Next, ytterbium (Yb) was vapor-deposited on the third electron transporting layer to form a 1-nm-thick electron injecting layer.
Next, Mg and Ag were co-deposited on the electron injecting layer of the second emitting unit at a mixing ratio (mass % ratio) of 10%:90%, thereby forming a semi-transparent upper electrode (cathode) that is made of an MgAg alloy and has a total film thickness of 15 nm.
Next, a compound Cap1 was formed on the entire surface of the upper electrode to form a 65-nm-thick capping layer.
A top emission type organic EL device of Example 2-1 was manufactured as described above.
A device arrangement of the organic EL device of Example 2-1 is roughly shown as follows.
An organic EL device of Example 2-2 was manufactured in the same manner as in Example 2-1 except that the compound used for forming the first organic layer was replaced by a compound HT3 shown in Table 2 and the compound HT2 used for forming the second hole transporting layer of the second emitting unit was replaced by the compound HT3.
An organic EL device of Comparative 2-1 was manufactured in the same manner as in Example 2-1 except that a third organic layer was formed between the second organic layer and the first organic layer and the thickness of the first organic layer was changed to 5 nm. In the organic EL device of Comparative 2-1, the compound HT1 was vapor-deposited on the second organic layer to form a 10-nm-thick third organic layer, on which the first organic layer was formed.
An organic EL device of Comparative 2-2 was manufactured in the same manner as in Comparative 2-1 except that the compound used for forming the first organic layer was replaced by the compound HT3 shown in Table 2 and the compound HT2 used for forming the second hole transporting layer of the second emitting unit was replaced by the compound HT3.
A glass substrate (size: 25 mm×75 mm×1.1 mm thick, manufactured by Geomatec Co., Ltd.) having an ITO (Indium Tin Oxide) transparent electrode (anode) was ultrasonic-cleaned in isopropyl alcohol for five minutes, and then UV-ozone-cleaned for 30 minutes. A film thickness of the ITO transparent electrode was 80 nm.
The cleaned glass substrate having the transparent electrode line was attached to a substrate holder of a vacuum deposition apparatus. First, the compound HT1 (second organic material) and the compound HA1 (third organic material) were co-deposited on a surface of the glass substrate, where the transparent electrode line was provided, to cover the transparent electrode, thereby forming a 10-nm-thick second organic layer. The ratios of the compound HT1 and the compound HA1 in the second organic layer were 97 mass % and 3 mass %, respectively.
After the formation of the second organic layer, the compound HT2 (first organic material) was vapor-deposited to form a 15-nm-thick first organic layer.
In Example 3-1, an anode side emitting unit (first emitting unit) including a first emitting layer, a second emitting layer and a first electron transporting layer was formed.
After the formation of the first organic layer, a compound BH2 (first host material) and the compound BD1 (first emitting compound) were co-deposited so that the ratio of the compound BD1 was 1 mass %, thereby forming a 5-nm-thick first emitting layer.
After the formation of the first emitting layer, the compound BH1 (second host material) and the compound BD1 (second emitting compound) were co-deposited so that the ratio of the compound BD1 was 1 mass %, thereby forming a 15-nm-thick second emitting layer.
Next, the compound ET1 was vapor-deposited on the second emitting layer to form a 5-nm-thick first electron transporting layer (also referred to as a hole blocking layer).
In Example 3-1, a charge generating unit including a first N layer and a first P layer was formed.
The compound ET2 and Li were co-deposited on the first electron transporting layer of the anode side emitting unit to form a 50-nm-thick first N layer.
The concentrations of the compound ET2 and Li in the first N layer were 96 mass % and 4 mass %, respectively.
Next, the compound HT1 and the compound HA1 were co-deposited on the first N layer to form a 10-nm-thick first P layer. The concentrations of the compound HT1 and the compound HA1 in the first P layer were 97 mass % and 3 mass %, respectively.
In Example 3-1, a second emitting unit (phosphorescent emitting unit) was formed that included a first hole transporting layer, a red phosphorescent emitting layer, a green phosphorescent emitting layer, a second electron transporting layer and an electron injecting layer.
The compound HT1 was vapor-deposited on the first P layer of the charge generating unit to form a 10-nm-thick first hole transporting layer.
Next, the compound PRH1 (phophorescent host material) and the phosphorescent compound PRD1 were co-deposited on the first hole transporting layer to form a 5-nm-thick red phosphorescent emitting layer. The concentrations of the compound PRH1 and the compound PRD1 in the red phosphorescent emitting layer were 96 mass % and 4 mass %, respectively.
Next, the compound PGH1 (phophorescent host material) and the phosphorescent compound PGD1 were co-deposited on the red phosphorescent emitting layer to form a 30-nm-thick green phosphorescent emitting layer. The concentrations of the compound PGH1 and the compound PGD1 in the green phosphorescent emitting layer were 97 mass % and 3 mass %, respectively.
Next, the compound ET3 and Liq were co-deposited on the green phosphorescent emitting layer to form a 40-nm-thick second electron transporting layer. The concentrations of the compound ET3 and Liq in the second electron transporting layer were 50 mass % and 50 mass %, respectively.
Next, ytterbium (Yb) was vapor-deposited on the second electron transporting layer to form a 1-nm-thick electron injecting layer.
Metal A1 was vapor-deposited on the electron injecting layer of the second emitting unit to form an 80-nm-thick cathode.
A bottom emission type organic EL device of Example 3-1 was manufactured as described above.
A device arrangement of the organic EL device of Example 3-1 is roughly shown as follows.
An organic EL device of Example 3-2 was manufactured in the same manner as in Example 3-1 except that the compound (first organic material) used for forming the first organic layer was replaced by the compound shown in Table 3.
An organic EL device of Comparative 3-1 was manufactured in the same manner as in Example 3-1 except that a third organic layer was formed between the second organic layer and the first organic layer and the thickness of the first organic layer was changed to 5 nm. In the organic EL device of Comparative 3-1, the compound HT1 was vapor-deposited on the second organic layer to form a 10-nm-thick third organic layer, on which the first organic layer was formed.
An organic EL device of Comparative 3-2 was manufactured in the same manner as in Comparative 3-1 except that the compound (first organic material) used for forming the first organic layer was replaced by the compound shown in Table 3.
A 100-nm-thick APC (Ag—Pd—Cu) layer (reflective layer), which was silver alloy layer, and a 10-nm-thick indium oxide-zinc oxide (IZO: registered trademark) layer (transparent conductive layer) were sequentially formed by sputtering on a glass substrate (25 mm×75 mm×0.7 mm thick) to be a substrate for manufacturing a device. A conductive material layer made of the APC layer and the IZO layer was thus obtained.
Subsequently, the conductive material layer was patterned by etching using a resist pattern as a mask using a normal lithography technique to form a lower electrode (anode).
Next, the compound HT1 (second organic material) and the compound HA1 (third organic material) were co-deposited on the lower electrode (anode) to form a 7-nm-thick second organic layer. The ratios of the compound HT1 and the compound HA1 in the second organic layer were 97 mass % and 3 mass %, respectively.
After the formation of the second organic layer, the compound HT2 (first organic material) was vapor-deposited to form a 15-nm-thick first organic layer.
In Example 4-1, an anode side emitting unit (first emitting unit) including a first emitting layer, a second emitting layer and a first electron transporting layer was formed.
After the formation of the first organic layer, the compound BH2 (first host material) and the compound BD1 (first emitting compound) were co-deposited so that the ratio of the compound BD1 was 1 mass %, thereby forming a 5-nm-thick first emitting layer.
After the formation of the first emitting layer, the compound BH1 (second host material) and the compound BD1 (second emitting compound) were co-deposited so that the ratio of the compound BD1 was 1 mass %, thereby forming a 15-nm-thick second emitting layer.
Next, the compound ET1 was vapor-deposited on the second emitting layer to form a 5-nm-thick first electron transporting layer (also referred to as a hole blocking layer).
In Example 4-1, a charge generating unit including a first N layer and a first P layer was formed.
The compound ET2 and Li were co-deposited on the first electron transporting layer of the anode side emitting unit to form a 70-nm-thick first N layer.
The concentrations of the compound ET2 and Li in the first N layer were 96 mass % and 4 mass %, respectively.
Next, the compound HT1 and the compound HA1 were co-deposited on the first N layer to form a 10-nm-thick first P layer. The concentrations of the compound HT1 and the compound HA1 in the first P layer were 90 mass % and 10 mass %, respectively.
In Example 4-1, a second emitting unit was formed that included a first hole transporting layer, a second hole transporting layer, a first emitting layer, a second emitting layer, a second electron transporting layer, a third electron transporting layer and an electron injecting layer.
The compound HT1 was vapor-deposited on the first P layer of the charge generating unit to form a 10-nm-thick first hole transporting layer.
Next, the compound HT2 was vapor-deposited on the first hole transporting layer to form a 5-nm-thick second hole transporting layer (also referred to as an electron blocking layer).
Next, the compound BH2 and the compound BD1 were co-deposited on the second hole transporting layer so that the ratio of the compound BD1 was 1 mass %, thereby forming a 5-nm-thick first emitting layer (UT2-EM1).
Next, the compound BH1 and the compound BD1 were co-deposited on the first emitting layer (UT2-EM1) so that the ratio of the compound BD1 was 1 mass %, thereby forming a 15-nm-thick second emitting layer (UT2-EM2).
Next, the compound ET1 was vapor-deposited on the second emitting layer (UT2-EM2) to form a 5-nm-thick second electron transporting layer (also referred to as a hole blocking layer).
Next, the compound ET3 and Liq were co-deposited on the second electron transporting layer to form a 25-nm-thick third electron transporting layer. The concentrations of the compound ET3 and Liq in the third electron transporting layer were 50 mass % and 50 mass %, respectively.
Next, ytterbium (Yb) was vapor-deposited on the third electron transporting layer to form a 1-nm-thick electron injecting layer.
Next, Mg and Ag were co-deposited on the electron injecting layer of the second emitting unit at a mixing ratio (mass % ratio) of 10%:90%, thereby forming a semi-transparent upper electrode (cathode) that is made of an MgAg alloy and has a total film thickness of 15 nm.
Next, the compound Cap1 was formed on the entire surface of the upper electrode to form a 65-nm-thick capping layer.
A top emission type organic EL device of Example 4-1 was manufactured as described above.
A device arrangement of the organic EL device of Example 4-1 is roughly shown as follows.
An organic EL device of Example 4-2 was manufactured in the same manner as in Example 4-1 except that the compound used for forming the first organic layer was replaced by the compound HT3 shown in Table 4 and the compound HT2 used for forming the second hole transporting layer of the second emitting unit was replaced by the compound HT3.
An organic EL device of Comparative 4-1 was manufactured in the same manner as in Example 4-1 except that a third organic layer was formed between the second organic layer and the first organic layer and the thickness of the first organic layer was changed to 5 nm. In the organic EL device of Comparative 4-1, the compound HT1 was vapor-deposited on the second organic layer to form a 10-nm-thick third organic layer, on which the first organic layer was formed.
An organic EL device of Comparative 4-2 was manufactured in the same manner as in Comparative 4-1 except that the compound used for forming the first organic layer was replaced by the compound HT3 shown in Table 4 and the compound HT2 used for forming the second hole transporting layer of the second emitting unit was replaced by the compound HT3.
The manufactured organic EL devices were evaluated as follows. Tables 1, 2, 3 and 4 show evaluation results.
A main peak wavelength and peak intensity of blue fluorescence obtained from the organic EL device was measured as follows.
Voltage was applied to the organic EL device so that the current density reached a predetermined value, where spectral radiance spectrum was measured by a spectroradiometer CS-2000 (manufactured by Konica Minolta, Inc.). In Examples, the spectral radiance spectrum was measured at a current density of 10 mA/cm2 and 0.01 mA/cm2.
In the obtained spectral radiance spectrum, an intensity of the emission spectrum at 460 nm, which was near a peak wavelength of blue emission spectrum, was measured and this emission spectrum intensity was defined as a “main peak intensity of blue fluorescence” in this evaluation. A ratio of a main peak intensity of an organic EL device of each Example to a main peak intensity of an organic EL device of reference Example was calculated as an EL peak intensity ratio (%) using the following numerical formula (Numerical Formula 1X), comparing blue emission efficiencies.
EL Peak Intensity Ratio (%)=(Main Peak Intensity of Each Example/Main Peak Intensity of Reference Example)×100 (Numerical Formula 1X)
Voltage was applied to the organic EL device so that a current density was 50 mA/cm2, where an emission spectrum was measured for each current-application time by a spectroradiometer CS-2000 (manufactured by Konica Minolta, Inc.). In the obtained spectral radiance spectrum, an intensity of the emission spectrum at 460 nm, which was in a blue wavelength region, was measured and this emission spectrum intensity was defined as a “main peak intensity of blue fluorescence” in this evaluation. A ratio of the main peak intensity after the current was applied relative to the initial main peak intensity was calculated. A time elapsed before the main peak intensity decreased by 5% relative to the initial main peak intensity was defined as a 5%-decrease lifetime (unit: minute). That is, the 5%-decrease lifetime refers to a time elapsed before the main peak intensity decreases to 0.95X provided that the initial main peak intensity is X.
Further, a ratio of a 5%-decrease lifetime of an organic EL device of each Example to a 5%-decrease lifetime of an organic EL device of a reference Example was calculated as a 5%-decrease lifetime ratio (%) using the following numerical formula (Numerical Formula 1Y).
5%-decrease Lifetime Ratio (%)=(5%-decrease Lifetime of Each Example/5%-decrease Lifetime of Reference Example)×100 (Numerical Formula 1Y)
Table 1 shows device evaluation where comparison was performed using the organic EL device of Example 1-1 as a reference. It should be noted that evaluation data as a reference is denoted by (Ref) in Table 1. Regarding the device performance when the device was driven at 0.01 mA/cm2, Example 1-1 and Example 1-2 were not decreased compared with Comparative 1-1 and Comparative 1-2, as shown in Table 1. It is considered that the longer lifetime is achieved by an increased supply of holes from the first organic layer to the first emitting layer at a high current density and the prevention of decrease in efficiency at a low current density is achieved by an increased supply of holes at a low current density.
Table 2 shows device evaluation where comparison was performed using the organic EL device of Example 2-1 as a reference. It should be noted that evaluation data as a reference is denoted by (Ref) in Table 2. Regarding the device performance when the device was driven at 0.01 mA/cm2, Example 2-1 and Example 2-2 were not decreased compared with Comparative 2-1 and Comparative 2-2, as shown in Table 2.
Table 3 shows device evaluation where comparison was performed using the organic EL device of Example 3-1 as a reference. It should be noted that evaluation data as a reference is denoted by (Ref) in Table 3. Regarding the device performance when the device was driven at 0.01 mA/cm2, Example 3-1 and Example 3-2 were not decreased compared with Comparative 3-1 and Comparative 3-2, as shown in Table 3.
Table 4 shows device evaluation where comparison was performed using the organic EL device of Example 4-1 as a reference. It should be noted that evaluation data as a reference is denoted by (Ref) in Table 4. Regarding the device performance when the device was driven at 0.01 mA/cm2, Example 4-1 and Example 4-2 were not decreased compared with Comparative 4-1 and Comparative 4-2, as shown in Table 4.
The compounds used for manufacturing the organic EL devices were evaluated as follows. Table 1 to 4 or 5 show evaluation results.
An ionization potential was measured under atmosphere using a photoelectron spectroscope (“AC-3” manufactured by RIKEN KEIKI Co., Ltd.).
Specifically, the material was irradiated with light and the amount of electrons generated by charge separation was measured to determine the ionization potential of the compound. The ionization potential is occasionally denoted by Ip.
A maximum peak wavelength of a fluorescent compound was measured as follows. A measurement target compound was dissolved in toluene at a concentration of 4.9×10−6 mol/L to prepare a toluene solution thereof. Using a fluorescence spectrometer (spectrophotofluorometer F-7000 manufactured by Hitachi High-Tech Science Corporation), the toluene solution of the measurement target compound was excited at 390 nm, where a maximum fluorescence peak wavelength λFL (unit: nm) was measured.
The maximum fluorescence peak wavelength λFL of the compound BD1 was 453 nm.
A maximum peak wavelength of a phosphorescent compound was measured as follows. A measurement target emitting compound and a host material in the emitting layer containing the emitting compound were co-deposited on a quartz substrate at the same ratio as in the emitting layer, thereby forming a 50-nm-thick film. Using a spectrophotofluorometer F-7000 (manufactured by Hitachi High-Tech Science Corporation), the emission spectrum of the film excited by light was measured. In the obtained emission spectrum, a peak wavelength where a luminous intensity was at the maximum was measured and defined as a maximum peak wavelength APH (unit: nm) of the phosphorescent compound.
A maximum phosphorescence peak wavelength APH of the compound PRD1 was 621 nm.
A maximum phosphorescence peak wavelength APH of the compound PGD1 was 529 nm.
A measurement target compound was dissolved in EPA (diethylether:isopentane:ethanol=5:5:2 in volume ratio) at a concentration of 10 μmol/L, and the obtained solution was put in a quartz cell to provide a measurement sample. A phosphorescence spectrum (ordinate axis: phosphorescent luminous intensity, abscissa axis: wavelength) of the measurement sample was measured at a low temperature (77K). A tangent was drawn to the rise of the phosphorescence spectrum close to the short-wavelength region. An energy amount was calculated by a conversion equation (F1) below on a basis of a wavelength value λedge [nm] at an intersection of the tangent and the abscissa axis. The calculated energy amount was defined as triplet energy T1. It should be noted that the triplet energy T1 has an error of about plus or minus 0.02 eV depending on measurement conditions.
T
1 [eV]=1239.85/λedge Conversion Equation (F1):
The tangent to the rise of the phosphorescence spectrum close to the short-wavelength region is drawn as follows. While moving on a curve of the phosphorescence spectrum from the short-wavelength region to the local maximum value closest to the short-wavelength region among the local maximum values of the phosphorescence spectrum, a tangent is checked at each point on the curve toward the long-wavelength of the phosphorescence spectrum. An inclination of the tangent is increased along the rise of the curve (i.e., a value of the ordinate axis is increased). A tangent drawn at a point of the local maximum inclination (i.e., a tangent at an inflection point) is defined as the tangent to the rise of the phosphorescence spectrum close to the short-wavelength region.
A local maximum point where a peak intensity is 15% or less of the maximum peak intensity of the spectrum is not counted as the above-mentioned local maximum peak intensity closest to the short-wavelength region. The tangent drawn at a point that is closest to the local maximum peak intensity closest to the short-wavelength region and where the inclination of the curve is the local maximum is defined as a tangent to the rise of the phosphorescence spectrum close to the short-wavelength region.
For phosphorescence measurement, a spectrophotofluorometer body F-4500 (manufactured by Hitachi High-Technologies Corporation) was used.
A toluene solution of a measurement target compound at a concentration of 10 μmol/L was prepared and put in a quartz cell. An absorption spectrum (ordinate axis: absorption intensity, abscissa axis: wavelength) of the thus-obtained sample was measured at a normal temperature (300K). A tangent was drawn to the fall of the absorption spectrum close to the long-wavelength region, and a wavelength value λedge (nm) at an intersection of the tangent and the abscissa axis was assigned to a conversion equation (F2) below to calculate the singlet energy.
S
1 [eV]=1239.85/λedge Conversion Equation (F2):
A spectrophotometer (U3310 manufactured by Hitachi, Ltd.) was used for measuring absorption spectrum.
The tangent to the fall of the absorption spectrum close to the long-wavelength region is drawn as follows. While moving on a curve of the absorption spectrum from the local maximum value closest to the long-wavelength region, among the local maximum values of the absorption spectrum, in a long-wavelength direction, a tangent at each point on the curve is checked. An inclination of the tangent is decreased and increased in a repeated manner as the curve falls (i.e., a value of the ordinate axis is decreased). A tangent drawn at a point where the inclination of the curve is the local minimum closest to the long-wavelength region (except when absorbance is 0.1 or less) is defined as the tangent to the fall of the absorption spectrum close to the long-wavelength region.
The local maximum absorbance of 0.2 or less is not counted as the above-mentioned local maximum absorbance closest to the long-wavelength region.
Number | Date | Country | Kind |
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2021-133502 | Aug 2021 | JP | national |