Patent Application
20240284693
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 voltage is applied to an organic EL device, holes are injected from an anode and electrons are injected from a cathode 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%.
For instance, in Patent Literatures 1, 2 and 3, various studies have been made to layer a plurality of emitting layers in order to enhance the performance of the organic EL device. Patent Literature 4, in order to enhance the performance of an organic EL device, describes a phenomenon in which a singlet exciton is generated by collision and fusion of two triplet excitons (hereinafter, occasionally referred to as a Triplet-Triplet Fusion (TTF) phenomenon).
The performance of the organic EL device is evaluable in terms of, for instance, luminance, emission wavelength, chromaticity, luminous efficiency, drive voltage, and lifetime.
An object of the invention is to provide an organic electroluminescence device with a long lifetime and an electronic device including the organic electroluminescence device.
According to an aspect of the invention, there is provided an organic electroluminescence device that includes an anode, a cathode, and an emitting region disposed between the anode and the cathode, in which the emitting region includes a first emitting layer and a second emitting layer, one of the first emitting layer and the second emitting layer is disposed on a side close to the anode in the emitting region, the first emitting layer contains a first host material and a first emitting compound, the second emitting layer contains a second host material and a second emitting compound, the first host material and the second host material are mutually different, the first emitting compound and the second emitting compound are mutually the same or different, a triplet energy of the first host material T1(H1) and a triplet energy of the second host material T1 (H2) satisfy a relationship of a numerical formula (Numerical Formula 1) below, and the first host material, the first emitting compound, the second host material, and the second emitting compound satisfy relationships of numerical formulae (Numerical Formula 2A) and (Numerical Formula 2B) below when the first emitting layer is disposed between the second emitting layer and the anode, and satisfy relationships of numerical formulae (Numerical Formula 3A) and (Numerical Formula 3B) below when the second emitting layer is disposed between the first emitting layer and the anode.
where:
According to an aspect of the invention, there is provided an electronic device including the organic electroluminescence device according to an aspect of the invention.
According to an aspect of the invention, an organic electroluminescence device with a long lifetime and an electronic device including the organic electroluminescence device can be provided.
Herein, a hydrogen atom includes isotope 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 is 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 does 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.
Substituent Mentioned Herein Substituent 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.
Substituted or Unsubstituted Aryl Group 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 G11B). (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 G1 B 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 G1 B below, and a group derived by further substituting a hydrogen atom of a substituent of the “substituted aryl group” in the specific example group G1 B below.
Unsubstituted Aryl Group (Specific Example Group G1A): 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, 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 monovalent aryl group derived by removing one hydrogen atom from cyclic structures represented by formulae (TEMP-1) to (TEMP-15) below.
Substituted Aryl Group (Specific Example Group G1 B): an 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 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 an “unsubstituted heterocyclic group” and a “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.
a 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.
a furyl group, oxazolyl group, isoxazolyl group, oxadiazolyl group, xanthenyl group, benzofuranyl group, isobenzofuranyl group, dibenzofuranyl group, naphthobenzofuranyl group, benzoxazolyl group, benzisoxazolyl group, phenoxazinyl group, morpholino group, dinaphthofuranyl group, azadibenzofuranyl group, diazadibenzofuranyl group, azanaphthobenzofuranyl group, and diazanaphthobenzofuranyl group.
a 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).
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.
Substituted Heterocyclic Groups Including Nitrogen Atom (Specific Example Group G2B1):
a phenyldibenzofuranyl group, methyldibenzofuranyl group, t-butyldibenzofuranyl group, and monovalent residue of spiro[9H-xanthene-9,9′-[9H]fluorene].
a phenyldibenzothiophenyl group, methyldibenzothiophenyl group, t-butyldibenzothiophenyl group, and monovalent residue of spiro[9H-thioxanthene-9,9′-[9H]fluorene].
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 an “unsubstituted alkyl group” and a “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.
a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, and t-butyl group.
a 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 an “unsubstituted alkenyl group” and a “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.
a vinyl group, allyl group, 1-butenyl group, 2-butenyl group, and 3-butenyl group.
a 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.
an 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.
a 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;
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;
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 “unsubstituted 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, and 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. A 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, p3-naphthylmethyl group, 1-β-naphthylethyl group, 2-β-naphthylethyl group, 1-β-naphthylisopropyl group, and 2-β3-naphthylisopropyl group.
Preferable examples of the substituted or unsubstituted aryl group mentioned herein include, unless otherwise specified herein, a phenyl group, β-biphenyl group, m-biphenyl group, o-biphenyl group, β-terphenyl-4-yl group, β-terphenyl-3-yl group, β-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 Q 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 (TEMP-104) is a benzene ring, the ring QA is a monocyclic ring. When the ring QA in the formula (TEMP-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
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
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, the substituent for the substituted or unsubstituted group (hereinafter sometimes referred to as an “optional substituent”), 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;
In an exemplary embodiment, the substituent for the substituted or unsubstituted group is a group 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, the substituent for the substituted or unsubstituted group is a group 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
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.”
An organic electroluminescence device according to the exemplary embodiment includes an anode, a cathode, and an emitting region disposed between the anode and the cathode, in which the emitting region includes a first emitting layer and a second emitting layer, one of the first emitting layer and the second emitting layer is disposed on a side close to the anode in the emitting region, the first emitting layer contains a first host material and a first emitting compound, the second emitting layer contains a second host material and a second emitting compound, the first host material and the second host material are mutually different, the first emitting compound and the second emitting compound are mutually the same or different, a triplet energy of the first host material T1(H1) and a triplet energy of the second host material T1(H2) satisfy a relationship of a numerical formula (Numerical Formula 1) below, and the first host material, the first emitting compound, the second host material, and the second emitting compound satisfy relationships of numerical formulae (Numerical Formula 2A) and (Numerical Formula 2B) below when the first emitting layer is disposed between the second emitting layer and the anode, and satisfy relationships of numerical formulae (Numerical Formula 3A) and (Numerical Formula 3B) below when the second emitting layer is disposed between the first emitting layer and the anode.
where:
LUMO(H1) is an energy level of a lowest unoccupied molecular orbital of the first host material;
LUMO(D1) is an energy level of a lowest unoccupied molecular orbital of the first emitting compound;
LUMO(H2) is an energy level of a lowest unoccupied molecular orbital of the second host material;
LUMO(D2) is an energy level of a lowest unoccupied molecular orbital of the second emitting compound;
HOMO(H1) is an energy level of a highest occupied molecular orbital of the first host material;
HOMO(D1) is an energy level of a highest occupied molecular orbital of the first emitting compound;
HOMO(H2) is an energy level of a highest occupied molecular orbital of the second host material; and
HOMO(D2) is an energy level of a highest occupied molecular orbital of the second emitting compound.
|LUMO(H1)| is an absolute value of an energy level of a lowest unoccupied molecular orbital of the first host material.
|LUMO(D1)| is absolute value of an energy level of a lowest unoccupied molecular orbital of the first emitting compound.
|LUMO(H2)| is an absolute value of an energy level of a lowest unoccupied molecular orbital of the second host material.
|LUMO(D2)| is an absolute value of an energy level of a lowest unoccupied molecular orbital of the second emitting compound.
|HOMO(H1)| is an absolute value of an energy level of a highest occupied molecular orbital of the first host material.
|HOMO(D1)| is an absolute value of an energy level of a highest occupied molecular orbital of the first emitting compound.
|HOMO(H2) is an absolute value of an energy level of a highest occupied molecular orbital of the second host material.
|HOMO(D2)| is an absolute value of an energy level of a highest occupied molecular orbital of the second emitting compound.
|LUMO(H1)-LUMO(D1)| is an absolute value of a difference between an energy level of a lowest unoccupied molecular orbital of the first host material and an energy level of a lowest unoccupied molecular orbital of the first emitting compound.
|LUMO(H2)-LUMO(D2)| is an absolute value of a difference between an energy level of a lowest unoccupied molecular orbital of the second host material and an energy level of a lowest unoccupied molecular orbital of the second emitting compound.
|HOMO(H1)-HOMO(D1)| is an absolute value of a difference between an energy level of a highest occupied molecular orbital of the first host material and an energy level of a highest occupied molecular orbital of the first emitting compound.
|HOMO(H2)-HOMO(D2)| is an absolute value of a difference between an energy level of a highest occupied molecular orbital of the second host material and an energy level of a highest occupied molecular orbital of the second emitting compound.
In the organic EL device according to the exemplary embodiment, the first emitting layer may be disposed between the second emitting layer and the anode. In this case, in the emitting region of the organic EL device according to the exemplary embodiment, the first emitting layer is disposed on a side closer to the anode and the second emitting layer is disposed on a side closer to the cathode.
In the organic EL device according to the exemplary embodiment, the second emitting layer may be disposed between the first emitting layer and the anode. In this case, in the emitting region of the organic EL device according to the exemplary embodiment, the second emitting layer is disposed on a side closer to the anode and the first emitting layer is disposed on a side closer to the cathode.
In the organic EL device according to the exemplary embodiment, the anode, the first emitting layer, the second emitting layer, and the cathode may be provided in this order. Alternatively, the anode, the second emitting layer, the first emitting layer, and the cathode may be provided in this order. That is, the anode, the second emitting layer, the first emitting layer, and the cathode may be provided in this order. Irrespective of the order of the first emitting layer and the second emitting layer, the effects resulting from layering the first emitting layer and the second emitting layer can be expected by selecting a combination of materials satisfying the relationship of the numerical formula (Numerical Formula 1).
In the organic EL device according to the exemplary embodiment, the first emitting layer may be disposed between the second emitting layer and the anode. In this case, it is considered that when the first host material, the first emitting compound, the second host material and the second emitting compound satisfy the relationships of the formulae (Numerical Formula 2A) and (Numerical Formula 2B), electrons are not likely to be trapped in the second emitting layer and are likely trapped in the first emitting layer.
In the organic EL device according to the exemplary embodiment, the second emitting layer may be disposed between the first emitting layer and the anode. In this case, it is considered that when the first host material, the first emitting compound, the second host material and the second emitting compound satisfy the relationships of the formulae (Numerical Formula 3A) and (Numerical Formula 3B), holes are not likely to be trapped in the second emitting layer and are likely trapped in the first emitting layer.
By layering a plurality of emitting layers in the emitting region of the organic EL device of the exemplary embodiment, retaining holes or electrons at an interface between the emitting layers, not at an interface between the emitting layers and a neighboring layer, and separating regions of recombination between holes and electrons from the interface between the emitting layers and the neighboring layer, the organic EL device of the exemplary embodiment can attain a long lifetime. The neighboring layer refers to a layer that is in direct contact with, on a side closer to the anode, the emitting layer disposed on the side closer to the anode in the emitting region, or a layer that is in direct contact with, on a side closer to the cathode, the emitting layer disposed on the side closer to the cathode in the emitting region.
In the organic EL device according to the exemplary embodiment, when the first emitting layer is disposed between the second emitting layer and the anode, the first host material, the first emitting compound, the second host material, and the second emitting compound preferably satisfy a relationship of a numerical formula (Numerical Formula 2C) below.
In the organic EL device according to the exemplary embodiment, when the first emitting layer is disposed between the second emitting layer and the anode, the first emitting compound and the second emitting compound preferably satisfy a numerical formula (Numerical Formula 2D) below.
|LUMO(D1)|≥∥LUMO(D2)| (Numerical Formula 2D)
By satisfying the relationship of the formula (Numerical Formula 2D), electrons are easily trapped by the first emitting compound.
In the organic EL device of the exemplary embodiment, when the first emitting layer is disposed between the second emitting layer and the anode, the first host material and the second host material also preferably satisfy a relationship of a numerical formula (Numerical Formula 2E) below.
|HOMO(H2)|≥|HOMO(H1)| (Numerical Formula 2E)
By satisfying the relationship of the formula (Numerical Formula 2E), holes are blocked easily at the interface between the first emitting layer and the second emitting layer.
In the organic EL device of the exemplary embodiment, when the first emitting layer is disposed between the second emitting layer and the anode, the first host material and the first emitting compound also preferably satisfy a relationship of a numerical formula (Numerical Formula 2F) below.
By satisfying the relationship of the numerical formula (Numerical Formula 2F), holes are not likely to be trapped by the first emitting compound.
In the organic EL device of the exemplary embodiment, when the first emitting layer is disposed between the second emitting layer and the anode, an ionization potential of the first host material and an ionization potential of the first emitting compound are preferably not close to each other.
In the organic EL device of the exemplary embodiment, when the first emitting layer is disposed between the second emitting layer and the anode, the first host material and the first emitting compound also preferably satisfy a relationship of a numerical formula (Numerical Formula 2G) below.
By satisfying the relationship of the numerical formula (Numerical Formula 2G), holes are not likely to be trapped by the first emitting compound.
In the organic EL device of the exemplary embodiment, when the first emitting layer is disposed between the second emitting layer and the anode, the first host material and the second emitting compound also preferably satisfy a relationship of a numerical formula (Numerical Formula 2H) below.
By satisfying the relationship of the numerical formula (Numerical Formula 2H), holes are inhibited from being injected into the second emitting compound.
In the organic EL device of the exemplary embodiment, when the second emitting layer is disposed between the first emitting layer and the anode, the first host material, the first emitting compound, the second host material, and the second emitting compound preferably satisfy a relationship of a numerical formula (Numerical Formula 3C) below.
In the organic EL device of the exemplary embodiment, when the second emitting layer is disposed between the first emitting layer and the anode, the first host material, the first emitting compound, the second host material, and the second emitting compound preferably satisfy a relationship of a numerical formula (Numerical Formula 3D) below.
|HOMO(D2)|≥|HOMO(D1)| (Numerical Formula 3D)
By satisfying the relationship of the formula (Numerical Formula 3D), holes are trapped easily by the first emitting compound.
In the organic EL device of the exemplary embodiment, when the second emitting layer is disposed between the first emitting layer and the anode, the first host material and the second host material preferably also satisfy a numerical formula (Numerical Formula 3E) below.
|LUMO(H1)|≥|LUMO(H2)| (Numerical Formula 3E)
By satisfying the relationship of the numerical formula (Numerical Formula 3E), electrons are blocked easily at the interface between the first emitting layer and the second emitting layer.
In the organic EL device of the exemplary embodiment, when the second emitting layer is disposed between the first emitting layer and the anode, the first host material and the first emitting compound also preferably satisfy a numerical formula (Numerical Formula 3F) below.
By satisfying the relationship of the numerical formula (Numerical Formula 3F), electrons are not likely to be trapped by the first emitting compound.
In the organic EL device of the exemplary embodiment, when the second emitting layer is disposed between the first emitting layer and the anode, the first host material and the first emitting compound also preferably satisfy a relationship of a numerical formula (Numerical Formula 3G) below.
By satisfying the relationship of the numerical formula (Numerical Formula 3G), electrons are not likely to be trapped by the first emitting compound.
In the organic EL device of the exemplary embodiment, when the second emitting layer is disposed between the first emitting layer and the anode, the first host material and the second emitting compound also preferably satisfy a relationship of a numerical formula (Numerical Formula 3H) below.
By satisfying the relationship of the numerical formula (Numerical Formula 3H), electrons are inhibited from being injected into the second emitting compound. In the organic EL device of the exemplary embodiment, when the second emitting layer is disposed between the first emitting layer and the anode, the first host material and the second emitting compound more preferably satisfy a numerical formula (Numerical Formula 3HA) below, still more preferably a numerical formula (Numerical Formula 3HB) below.
Herein, an energy level of a highest occupied molecular orbital HOMO is measured using a photoelectron spectroscope under atmosphere. Specifically, the energy level of the highest occupied molecular orbital HOMO is measurable by a method described in Examples.
Herein, an energy level of a lowest unoccupied molecular orbital LUMO is a value calculated by using a formula (Numerical Formula 1X) below on the basis of measured values of the energy level of the highest occupied molecular orbital HOMO and the singlet energy Si. The units of the energy level of the lowest unoccupied molecular orbital LUMO, the energy level of the highest occupied molecular orbital HOMO and the singlet energy S1 are eV.
According to the exemplary embodiment, an organic electroluminescence device with improved luminous efficiency can be provided.
Conventionally, Triplet-Triplet-Annhilation (occasionally referred to as TTA) is known as a technique for enhancing the luminous efficiency of the organic electroluminescence device. TTA is a mechanism in which triplet excitons collide with one another to generate singlet excitons. The TTA mechanism is also referred to as a TTF mechanism as described in Patent Literature 4.
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 the 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 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.
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%×(⅕)=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 singlet 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% x (½)=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 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. The organic electroluminescence device according to the exemplary embodiment includes at least two emitting layers satisfying a predetermined relationship (i.e., the first and second emitting layers), in which the triplet energy of the first host material T1(H1) in the first emitting layer and the triplet energy of the second host material T1(H2) in the second emitting layer satisfy the relationship of the numerical formula (Numerical Formula 1).
By including the first emitting layer and the second emitting layer so as to satisfy the numerical formula (Numerical Formula 1), 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 effectively generate singlet excitons, thereby improving the luminous efficiency.
Accordingly, 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, the triplet energy of the first host material T1(H1) and the triplet energy of the second host material T1(H2) preferably satisfy a relationship of a numerical formula (Numerical Formula 5) below.
Herein, the “host material” refers to, for instance, a material that accounts for “50 mass % or more of the layer”. That is, for instance, the first emitting layer contains 50 mass % or more of the first host material with respect to the total mass of the first emitting layer. For instance, the second emitting layer contains 50 mass % or more of the second host material with respect to the total mass of the second emitting layer.
The organic electroluminescence device according to the exemplary embodiment preferably emits light having a maximum peak wavelength of 500 nm or less when the organic electroluminescence device is driven.
The organic electroluminescence device according to the exemplary embodiment more preferably emits light having a maximum peak wavelength in a range from 430 nm to 480 nm when the organic electroluminescence device is driven.
The maximum peak wavelength of the light emitted from the organic EL device when being driven is measured as follows. Voltage is applied to the organic EL device such that a current density becomes 10 mA/cm2, where spectral radiance spectrum is measured by a spectroradiometer CS-2000 (produced by Konica Minolta, Inc.). A peak wavelength of an emission spectrum, at which the luminous intensity of the obtained spectral radiance spectrum is at the maximum, is measured and defined as a maximum peak wavelength (unit: nm).
The first emitting layer contains the first host material. The first host material and the second host material that is contained in the second emitting layer are different compounds.
The first emitting layer contains the first emitting compound. The first emitting compound is also preferably a fluorescent compound that emits fluorescence.
The first emitting compound is preferably a compound that emits light having a maximum peak wavelength of 500 nm or less, more preferably a compound that emits light having a maximum peak wavelength of 480 nm or less. The first emitting compound is preferably a compound that emits light having a maximum peak wavelength of 430 nm or more.
The first emitting compound is more preferably a compound that emits fluorescence having a maximum peak wavelength of 500 nm or less, more preferably a compound that emits fluorescence having a maximum peak wavelength of 480 nm or less. The first emitting compound is preferably a compound that emits fluorescence having a maximum peak wavelength of 430 nm or more.
The first emitting compound and the first host material are different compounds.
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.
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, the first emitting layer preferably does not contain a phosphorescent material (dopant material).
In addition, 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.
A measurement method of the maximum peak wavelength of a compound is as follows. A toluene solution of a measurement target compound at a concentration of 5 μmol/L is prepared and put in a quartz cell. An emission spectrum (ordinate axis: luminous intensity, abscissa axis: wavelength) of each of the samples is measured at a normal temperature (300K). The emission spectrum can be measured using a spectrophotometer (machine name: F-7000) produced 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 peak wavelength. Herein, the maximum peak wavelength is occasionally referred to as a maximum fluorescence peak wavelength (FL-peak).
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, the first emitting layer preferably emits light having a maximum peak wavelength of 500 nm or less when the device is driven.
The maximum peak wavelength of the light emitted from the emitting layer when the device is driven is measured as follows.
Maximum Peak Wavelength λp of Light Emitted from Emitting Layer When Organic EL Device Is Driven
For a maximum peak wavelength λp1 of light emitted from the first emitting layer when the organic EL device is driven, the organic EL device is produced by using the material of the first emitting layer for the first emitting layer and the second emitting layer, and voltage is applied to the organic EL device so that a current density becomes 10 mA/cm2, where spectral radiance spectrum is measured by a spectroradiometer CS-2000 (produced by Konica Minolta, Inc.). The maximum peak wavelength λp1 (unit: nm) is calculated from the obtained spectral radiance spectrum.
For a maximum peak wavelength λp2 of light emitted from the second emitting layer when the organic EL device is driven, the organic EL device is produced by using the material of the second emitting layer for the first emitting layer and the second emitting layer, and voltage is applied to the organic EL device so that a current density becomes 10 mA/cm2, where spectral radiance spectrum is measured by a spectroradiometer CS-2000 (produced by Konica Minolta, Inc.). The maximum peak wavelength λp2 (unit: nm) is calculated from the obtained spectral radiance spectrum.
In the organic EL device according to the exemplary embodiment, a singlet energy of the first host material S1(H1) and a singlet energy of the first emitting compound S1(D1) 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 emission (preferably fluorescence) of the first emitting compound.
In the organic EL device according to the exemplary embodiment, the triplet energy of the first host material T1(H1) and a triplet energy of the first emitting compound T1(D1) 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 transfer not onto the first emitting compound having higher triplet energy but onto the first host material, thereby easily transferring 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.
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 encapsulated 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.
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. Any device for phosphorescence measurement is usable. A combination of a cooling unit, a low temperature container, an excitation light source and a light-receiving unit may be used for phosphorescence measurement.
A method of measuring the 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 is 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 is assigned to a conversion equation (F2) below to calculate singlet energy.
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.
In the organic EL device according to the exemplary embodiment, the first emitting layer preferably contains 0.5 mass % or more of the first emitting compound. In other words, the first emitting layer preferably contains 0.5 mass % or more of the first emitting compound with respect to the total mass of the first emitting layer.
The first emitting layer contains the first emitting compound preferably at 10 mass % or less, more preferably at 7 mass % or less, and still more 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 a first compound as the first host material at 60 mass % or more, more preferably at 70 mass % or more, still more preferably at 80 mass % or more, still further more preferably at 90 mass % or more, yet still further more preferably at 95 mass % or more, with respect to the total mass of the first emitting layer.
The first emitting layer preferably contains the first host material at 99 mass % or less with respect to the total mass of the first emitting layer.
When the first emitting layer contains the first host material and the first emitting compound, the upper limit of a total of the content ratios of the first host material and the first emitting compound is 100 mass %.
In the exemplary embodiment, the first emitting layer may further contain any other material than the first host material and the first emitting compound.
The first emitting layer may contain a single type of the first host material or may contain two or more types of the first host material. The first emitting layer may contain a single type of the first emitting compound or may contain two or more types of the first emitting compound.
In the organic EL device according to the exemplary embodiment, the first emitting layer may consist of the first host material and the first emitting compound.
In the organic EL device according to the exemplary embodiment, a film thickness of the first emitting layer is preferably 3 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, the film thickness of the first emitting layer is preferably 15 nm or less. When the film thickness of the first emitting layer is 15 nm or less, the film thickness is sufficiently thin to allow for transfer of triplet excitons to the second emitting layer.
In the organic EL device according to the exemplary embodiment, the film thickness of the first emitting layer is more preferably in a range from 3 nm to 15 nm.
The second emitting layer contains the second host material. The second host material and the first host material that is contained in the first emitting layer are different compounds.
The second emitting layer contains the second emitting compound. The second emitting compound is also preferably a fluorescent compound that emits fluorescence. The second emitting compound and the second host material are different compounds. The second emitting compound and the first emitting compound are mutually the same or different.
The second emitting compound is preferably a compound that emits light having a maximum peak wavelength of 500 nm or less, more preferably a compound that emits light having a maximum peak wavelength of 480 nm or less. The second emitting compound is preferably a compound that emits light having a maximum peak wavelength of 430 nm or more.
The second emitting compound is more preferably a compound that emits fluorescence having a maximum peak wavelength of 500 nm or less, still more preferably a compound that emits fluorescence having a maximum peak wavelength of 480 nm or less. The second emitting compound is preferably a compound that emits fluorescence having a maximum peak wavelength of 430 nm or more. 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, the second emitting layer preferably emits light having a maximum peak wavelength of 500 nm or less when the device is driven.
In the organic EL device according to the exemplary embodiment, the full width at half maximum 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 decrease in the luminous efficiency due to self-absorption is easily inhibited.
The self-absorption is a phenomenon in which 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 reduce 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 produced 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 was put into a quartz cell and was 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 produced 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 of the second emitting compound T1(D2) and a triplet energy of the second host material T1(H2) preferably satisfy a relationship of a numerical formula (Numerical Formula 3) below.
T
1(D2)>T1(H2) (Numerical Formula 3)
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 3), in transfer of triplet excitons generated in the first emitting layer to the second emitting layer, the triplet excitons energy-transfer 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 of the second host material S1(H2) and a singlet energy of the second emitting compound S1(D2) 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 emission (preferably, 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.
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, the second emitting layer preferably does not contain a phosphorescent material (dopant material).
In addition, 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 compound is preferably contained at 0.5 mass % or more in the second emitting layer. In other words, the second emitting layer preferably contains 0.5 mass % or more of the second emitting compound with respect to the total mass of the second emitting layer.
The second emitting layer contains the second emitting compound preferably at 10 mass % or less, more preferably at 7 mass % or less, and still more preferably at 5 mass % or less with respect to the total mass of the second emitting layer.
The second emitting layer contains a second compound as the second host material preferably at 60 mass % or more, more preferably at 70 mass % or more, still more preferably at 80 mass % or more, still further more preferably at 90 mass % or more, and yet still further more 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, the upper limit of a total of the content ratios of the second host material and the second emitting compound is 100 mass %.
In the exemplary embodiment, the second emitting layer may further contain any other material than the second host material and the second emitting compound.
The second emitting layer may contain a single type of the second host material or may contain two or more types of the second host material. The second emitting layer may contain a single type of the second emitting compound or may contain two or more types of the second emitting compound.
In the organic EL device according to the exemplary embodiment, the second emitting layer may consist of the second host material and the second emitting compound.
In the organic EL device according to the exemplary embodiment, a 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, a film thickness of the second emitting layer is preferably 25 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, the film thickness of the second emitting layer is preferably in a range from 5 nm to 25 nm.
In the organic EL device according to the exemplary embodiment, a triplet energy of the first emitting compound or the second emitting compound T1(DX), the triplet energy of the first host material T1(H1) and the triplet energy of the second host material T1(H2) preferably satisfy a relationship of a numerical formula (Numerical Formula 10) below.
The triplet energy of the first emitting compound T1(D1) preferably satisfies a relationship of a numerical formula (Numerical Formula 10A) below.
The triplet energy of the second emitting compound T1(D2) preferably satisfies a relationship of a numerical formula (Numerical Formula 10B) below.
In the organic EL device according to the exemplary embodiment, the triplet energy of the first emitting compound or the second emitting compound T1(DX) and the triplet energy of the first host material T1(H1) preferably satisfy a relationship of a numerical formula (Numerical Formula 11) below.
The triplet energy of the first emitting compound T1(D1) preferably satisfies a relationship of a numerical formula (Numerical Formula 11A) below.
The triplet energy of the second emitting compound T1(D2) preferably satisfies a relationship of a numerical formula (Numerical Formula 11 B) below.
In the organic EL device according to the exemplary embodiment, the triplet energy of the first host material T1(H1) preferably satisfies a relationship of a numerical formula (Numerical Formula 12) below.
T
1(H1)>2.0eV (Numerical Formula 12)
In the organic EL device according to the exemplary embodiment, the triplet energy of the first host material T1(H1) 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)>2.10eV (Numerical Formula 12A)
T
1(H1)>2.15eV (Numerical Formula 12B)
In the organic EL device according to the exemplary embodiment, when the triplet energy of the first host material T1(H1) 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 of the first host material T1(H1) 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.
In the organic EL device according to the exemplary embodiment, when the triplet energy of the first host material T1(H1) satisfies the relationship of the numerical formula (Numerical Formula 12C) or (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 of the first emitting compound T1(D1) 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.
2.60eV>T1(D1) (Numerical Formula 14A)
2.50eV>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 of the second emitting compound T1(D2) 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.
2.60eV>T1(D2) (Numerical Formula 14C)
2.50eV>T1(D2) (Numerical Formula 14D)
When the second emitting layer contains a 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 of the second host material T1(H2) preferably satisfies a relationship of a numerical formula (Numerical Formula 13) below.
T
1(H2)1.9 eV (Numerical Formula 13)
Additional Layers of Organic EL Device In addition to the first emitting layer and the second emitting layer, the organic EL device according to the exemplary embodiment may include one or more organic layers. Examples of the organic layer include at least one layer selected from the group consisting of a hole injecting layer, a hole transporting layer, an emitting layer, an electron injecting layer, an electron transporting layer, a hole blocking layer, and an electron blocking layer.
The layers of the organic EL device according to the exemplary embodiment may consist of the first emitting layer and the second emitting layer. Alternatively, the organic EL device according to the exemplary embodiment may further include, for instance, at least one layer selected from the group consisting of 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.
An organic EL device 1 includes a substrate 2, an anode 3, a cathode 4, and organic layers 10 provided between the anode 3 and the cathode 4. The organic layers 10 include a hole injecting layer 6, a hole transporting layer 7, a first emitting layer 51, a second emitting layer 52, an electron transporting layer 8, and an electron injecting layer 9 that are layered in this order from a side closer to the anode 3. An emitting region 5 of the organic EL device 1 includes the first emitting layer 51 disposed closer to the anode 3, and the second emitting layer 52 disposed closer to the cathode 4.
An organic EL device 1A includes a substrate 2, an anode 3, a cathode 4, and organic layers 10A provided between the anode 3 and the cathode 4. The organic layers 10A include a hole injecting layer 6, a hole transporting layer 7, a second emitting layer 52, a first emitting layer 51, an electron transporting layer 8, and an electron injecting layer 9 that are layered in this order from a side closer to the anode 3. An emitting region 5A of the organic EL device 1A includes the second emitting layer 52 disposed closer to the anode 3 and the first emitting layer 51 disposed closer to the cathode 4.
The invention is not limited to the exemplary arrangements of the organic EL device depicted in
Interposed Layer The organic EL device according to the exemplary embodiment may include an interposed layer as an organic layer disposed between the first emitting layer and the second emitting layer.
In the exemplary embodiment, in order to inhibit an overlap between a Singlet emitting region and a TTF emitting region, the interposed layer contains no emitting compound or may contain an emitting compound in an insubstantial amount provided that the overlap can be inhibited.
For instance, the interposed layer contains 0 mass % of an emitting compound. Alternatively, for instance, the interposed layer may contain an emitting compound provided that the emitting compound contained is a component accidentally mixed in a production process or a component contained as impurities in a material.
For instance, when the interposed layer consists of a material A, a material B, and a material C, the content ratios of the materials A, B, and C in the interposed layer are each 10 mass % or more, and the total of the content ratios of the materials A, B, and C is 100 mass %.
In the following, the interposed layer is occasionally referred to as a “non-doped layer”. A layer containing an emitting compound is occasionally referred to as a “doped layer”.
It is considered that luminous efficiency is improvable in an arrangement including layered emitting layers because the Singlet emitting region and the TTF emitting region are typically likely to be separated from each other.
In the organic EL device according to the exemplary embodiment, when the interposed layer (non-doped layer) is disposed between the first emitting layer and the second emitting layer in the emitting region, it is expected that a region where the Singlet emitting region and the TTF emitting region overlap with each other is reduced to inhibit a decrease in TTF efficiency caused by collision between triplet excitons and carriers. That is, it is considered that providing the interposed layer (non-doped layer) between the emitting layers contributes to the improvement in the efficiency of TTF emission.
The interposed layer is the non-doped layer.
The interposed layer contains no metal atom. The interposed layer thus contains no metal complex.
The interposed layer contains an interposed layer material. The interposed layer material is not an emitting compound.
The interposed layer material may be any material except for the emitting compound.
Examples of the interposed layer material 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.
One or both of the first host material and the second host material may be used as the interposed layer material. The interposed layer material may be any material provided that the Singlet emitting region and the TTF emitting region are separated from each other and the Singlet emission and the TTF emission are not hindered.
In the organic EL device according to the exemplary embodiment, the respective content ratios of all the materials forming the interposed layer in the interposed layer are 10 mass % or more.
The interposed layer contains the interposed layer material as a material forming the interposed layer.
The interposed layer preferably contains 60 mass % or more of the interposed layer material, more preferably contains 70 mass % or more of the interposed layer material, still more preferably contains 80 mass % or more of the interposed layer material, still further more preferably 90 mass % or more of the interposed layer material, yet still further more preferably 95 mass % or more of the interposed layer material, with respect to the total mass of the interposed layer.
The interposed layer may contain a single type of the interposed layer material or may contain two or more types of the interposed layer material.
When the interposed layer contains two or more types of the interposed layer material, an upper limit of the total of the content ratios of the two or more types of the interposed layer material is 100 mass %.
It should be noted that the interposed layer of the exemplary embodiment may further contain any other material than the interposed layer material.
The interposed layer may be provided in the form of a single layer or a laminate of two or more layers.
As long as the overlap between the Singlet emitting region and the TTF emitting region is inhibited, 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.
The interposed layer having a film thickness of 3 nm or more easily separates the Singlet emitting region from the emitting region derived from TTF.
The interposed layer having a film thickness of 15 nm or less easily inhibits a phenomenon where the host material of the interposed layer emits light.
It is preferable that the interposed layer contains the interposed layer material as a material forming the interposed layer and the triplet energy of the first host material T1(H1), the triplet energy of the second host material T1(H2), and a triplet energy of at least one interposed layer material T1(Mmid) satisfy a relationship of a numerical formula (Numerical Formula 21) below.
When the interposed layer contains two or more interposed layer materials as a material forming the interposed layer, the triplet energy of the first host material T1(H1), the triplet energy of the second host material T1(H2), and a triplet energy of each interposed layer material T1(MEA) more preferably satisfy a relationship of a numerical formula (Numerical Formula 21A) below.
In the organic EL device according to the exemplary embodiment, the first emitting layer and the second emitting layer are preferably 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 arrangements (LS1), (LS2) and (LS3) below.
(LS1) An arrangement 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 arrangement in which in a case of containing an emitting compound in the first emitting layer and the second emitting layer, a region containing 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 arrangement 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.
An arrangement of an organic EL device will be further described below. It should be noted that the reference numerals are occasionally omitted below.
Substrate 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. Further, an inorganic vapor deposition film is also usable.
Anode 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 indium tin oxide (ITO), 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 EL 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 AILi) 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.
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, 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 AILi) including the alkali metal or the alkaline earth metal, a 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.
Hole Injecting 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 include: an aromatic amine compound, which is a low-molecule organic compound, such that 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-molecule 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.
In the organic EL device according to the exemplary embodiment, a hole transporting layer is preferably disposed between the anode and one of the first emitting layer and the second emitting layer that is disposed closer to the anode.
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 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/(Vs) 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).
Electron Transporting Layer In the organic EL device according to the exemplary embodiment, an electron transporting layer is preferably disposed between the cathode and one of the first emitting layer and the second emitting layer that is disposed closer to the cathode. 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), BAIq, 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: β-EtTAZ), bathophenanthroline (abbreviation: BPhen), bathocuproine (abbreviation: BCP), and 4,4′-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviation: BzOs) is usable. In the exemplary embodiment, a benzimidazole compound is preferably 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).
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.
A method of 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.
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 an excessively small film thickness is likely to cause defects (e.g. pin holes) and an excessively large thickness leads to the necessity of applying high voltage and consequent reduction in efficiency.
In the organic EL device according to the exemplary embodiment, the first host material and the second host material may each be any compound that at least satisfies the three relationships of the numerical formulae (Numerical Formula 1), (Numerical Formula 2A) and (Numerical Formula 2B) or any compound that at least satisfies the three relationships of the numerical formulae (Numerical Formula 1), (Numerical Formula 3A) and (Numerical Formula 3B). The first host material and the second host material are each independently selected from the group consisting of compounds represented by a formula (1), a formula (1X), a formula (12X), a formula (13X), a formula (14X), a formula (15X), and a formula (16X) below and a compound represented by a formula (2) 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;
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 host material 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;
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;
Among positions *1 to *8 of carbon atoms in a cyclic structure represented by a formula (111a) below in the 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 the 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 (111 b) below.
In the formula (111 b):
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, preferably, ma is 0, 1, or 2, and mb is 0, 1 or 2.
In the organic EL device according to the exemplary embodiment, preferably, 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) each represent a bonding position to L101 in the formula (11), or a bonding position to L112 in the formula (111) or (111 b).
In the organic EL device according to the exemplary embodiment, the compound represented by the formula (1) 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 organic EL device according to the exemplary embodiment, L101 is preferably 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, the compound represented by the formula (1) 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), preferably, ma is 0, 1 or 2, and mb is 0, 1, or 2.
In the compound represented by the formula (102), preferably, ma is 0 or 1 and mb is 0 or 1.
In the organic EL device according to the exemplary embodiment, two or more of R101 to R110 are each preferably 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 for 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, R101 to R110 not being the group represented by the formula (11) 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 group represented by the formula (11) 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 group represented by the formula (11) are each preferably a hydrogen atom.
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 a 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, in the group represented by the formula (111X), when L111 is bonded to a carbon atom at *2 in the cyclic structure represented by the formula (111 aX) and L112 is bonded to a carbon atom at *7 in the cyclic structure represented by the formula (111aX), the group represented by the formula (111X) is represented by a formula (111bX) 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 a group represented by the formula (111bX).
In the compound represented by the formula (1X), preferably, ma is 1 or 2 and mb is 1 or 2.
In the compound represented by the formula (1X), preferably, 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 not being the bonding position to L101, and R133 or R134 not being the 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 not being the bonding position to L111, and R133 or R134 not being the 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), preferably, ma is 1 or 2 and mb is 1 or 2 in the formula (102X).
In the compound represented by the formula (1X), preferably, 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) or a group represented by a formula (11 BX) below.
In the formulae (11 AX) and (11 BX):
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 (11 AX) 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 (11 BX) are present, the plurality of groups represented by the formula (11 BX) 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; and
* in the formulae (11AX) and (11 BX) each represent 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 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 forming neither the substituted or unsubstituted monocyclic ring nor 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 is 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 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 a 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;
Ar13O1 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 in the formula (13X).
In the organic EL device according to 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 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—(R9so), 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 a 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 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 a 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 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 a 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 Ar1601 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 organic EL device according to the exemplary embodiment, it is also preferable that the first host material has, in a molecule, a linking structure including a benzene ring and a naphthalene ring linked to each other with a single bond, in which the benzene ring and the naphthalene ring in the linking structure are each independently fused or not fused with a further monocyclic ring or fused ring, and the benzene ring and the naphthalene ring in the linking structure are further linked to each other by cross-linking at at least one site other than the single bond.
When the first host material has the linking structure including such cross-linking, deterioration in the chromaticity of the organic EL device is expected to be inhibited.
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 (occasionally referred to as a benzene-naphthalene linking structure), the linking structure being as represented by a formula (X1) or a formula (X2) below. The benzene ring may be fused with a further monocyclic ring or fused ring, and the naphthalene ring may be fused with a further monocyclic ring or fused ring. For instance, also in a case where the first host material has, in a molecule, a linking structure including a naphthalene ring and a naphthalene ring linked to each other with a single bond (occasionally referred to as a naphthalene-naphthalene linking structure) 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 above exemplary embodiment, the cross-linking also preferably includes a double bond. Specifically, the first host material also preferably has a 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 the 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 cross-linking, for instance, 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) or formula (X22) 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 instance, 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 above exemplary embodiment, also preferably, the first host material 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 above exemplary embodiment, also preferably, the first benzene ring and the second benzene ring in the biphenyl structure are further linked to each other by the cross-linking at one site other than the single bond. When the first host material has the biphenyl structure including such cross-linking, deterioration in the chromaticity of the organic EL device is expected to be inhibited.
In the organic EL device according to the exemplary embodiment, the cross-linking also preferably includes a double bond. In the organic EL device according to the exemplary embodiment, the cross-linking also preferably includes no double bond.
Also preferably, the first benzene ring and the second benzene ring in the biphenyl structure are further linked to each other by the cross-linking at two sites other than the single bond.
In the organic EL device according to the exemplary embodiment, also preferably, the first benzene ring and the second benzene ring in the biphenyl structure are further linked to each other by the cross-linking at two sites other than the single bond, and the cross-linking includes no double bond. When the first host material has the biphenyl structure including such cross-linking, deterioration in the chromaticity of the organic EL device is expected to be inhibited.
For instance, 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 by cross-linking including no double bond at one of two sites other than the single bond, and the first benzene ring and the second benzene ring are linked to each other by cross-linking including a double bond at the other of the two sites other than the single 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 a double bond.
In the first host material and the second host material, the groups specified to be “substituted or unsubstituted” are each preferably an unsubstituted group.
Method of Producing Compounds Represented by Formulae (1), (1X), (12X), (13X), (14X), (15X) and (16X)
The compounds represented by the formulae (1), (1X), (12X), (13X), (14X), (15X) and (16X) can be produced by a known method or can be produced based on a known method through a known alternative reaction using a known material(s) tailored for the target compound.
Specific Examples of Compounds Represented by Formulae (1), (1X), (12X), (13X), (14X), (15X) and (16X)
Specific examples of compounds represented by the formulae (1), (1X), (12X), (13X), (14X), (15X), and (16X) include compounds below. However, the invention is by no means limited to the specifically listed compounds.
In the specific examples of the compound herein, D represents a deuterium atom, Me represents a methyl group, and tBu represents a tert-butyl group.
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 compound represented by the formula (2) according to the exemplary embodiment, R901, R902, R903, R904, R905, R905, 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 R90s are present, the plurality of R90s are mutually the same or different;
when a plurality of R90s are present, the plurality of R90s 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; 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 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, Ar201 and Ar202 are preferably each independently a phenyl group, a naphthyl group, a 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 compound represented by the formula (2) is preferably a compound represented by a formula (201), a formula (202), a formula (203), a formula (204), a formula (205), a formula (206), a formula (207), a formula (208), or a formula (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 compound represented by the formula (2) is also preferably a compound represented by a formula (221), a formula (222), a formula (223), a formula (224), a formula (225), a formula (226), a formula (227), a formula (228), or a formula (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
Ar2O3 and Ar201 are mutually the same or different.
The compound represented by the formula (2) is also preferably a compound represented by a formula (241), a formula (242), a formula (243), a formula (244), a formula (245), a formula (246), a formula (247), a formula (248), or a formula (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.
In the compound represented by the formula (2), R201 to R208 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).
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 embodiment, it is also preferable that R201 to R208 in the 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).
In the organic EL device according to the exemplary embodiment, R201 to R208 in the compound represented by the formula (2) are each preferably a hydrogen atom.
In the compound represented by the formula (2), the groups specified to be “substituted or unsubstituted” are each preferably an unsubstituted group.
The compound represented by the formula (2) can be produced by a known method. The compound represented by the formula (2) can also be produced based on a known method through a known alternative reaction using a known material(s) tailored for the target compound.
Specific examples of the compound represented by the formula (2) include compounds below. However, the invention is by no means limited to the specific examples of the compound represented by the formula (2).
In the organic EL device according to the exemplary embodiment, the first emitting compound and the second emitting compound are compounds different from the first host material and the second host material.
In the organic EL device according to the exemplary embodiment, the first emitting material and the second emitting material may each be any compound that at least satisfies the three relationships of the numerical formulae (Numerical Formula 1), (Numerical Formula 2A), and (Numerical Formula 2B) or any compound that at least satisfies the three relationships of the numerical formulae (Numerical Formula 1), (Numerical Formula 3A), and (Numerical Formula 3B).
In the organic EL device according to the exemplary embodiment, the first emitting layer may be disposed between the anode and the second emitting layer. In this case, electrons are retained at the interface between the emitting layers and the recombination zone is separated from the interface between the emitting layers and the surrounding layers, by appropriately using, each independently, as the first emitting compound and the second emitting compound, at least one compound that is selected from the group consisting of a compound represented by formulae (31-1) and (31-3) below, a compound represented by formulae (31-2) and (31-3) below, a compound represented by a formula (41) below, and a compound represented by a formula (50) below and that at least satisfies the three relationships of the formulae (Numerical Formula 1), (Numerical Formula 2A), and (Numerical Formula 2B). This arrangement is expected to extend the lifetime of the device.
The compound represented by the formulae (31-1) and (31-3) or the compound represented by the formulae (31-2) and (31-3) will be described.
Also preferably, the first emitting compound and the second emitting compound are each the compound represented by the formulae (31-1) and (31-3) below or the compound represented by the formulae (31-2) and (31-3) below.
In the formulae (31-1), (31-2), and (31-3):
a ring A 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;
two * in the formula (31-1) are each independently bonded to a ring carbon atom of the aromatic hydrocarbon ring or a ring atom of the heterocycle as the ring A in the formula (31-3);
three * in the formula (31-2) are each independently bonded to a ring-forming carbon atom of the aromatic hydrocarbon ring or a ring atom of the heterocycle as the ring A in the formula (31-3);
at least one combination of adjacent two or more of R1 to R16 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
R1 to R16 forming neither the substituted or unsubstituted monocyclic ring nor 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 substituted or unsubstituted alkoxy group having 1 to 50 carbon atoms, a substituted or unsubstituted alkylthio group having 1 to 50 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 50 ring carbon atoms, a substituted or unsubstituted arylthio group having 6 to 50 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —Si(R31)(R32)(R33), a group represented by —C(═O)R34, a group represented by —COOR35, a group represented by —N(R36)(R37), 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 formulae (31-1), (31-2), and (31-3):
R31 to R37 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 R31 are present, the plurality of R31 are mutually the same or different;
when a plurality of R32 are present, the plurality of R32 are mutually the same or different;
when a plurality of R33 are present, the plurality of R33 are mutually the same or different;
when a plurality of R34 are present, the plurality of R34 are mutually the same or different;
when a plurality of R35 are present, the plurality of R35 are mutually the same or different;
when a plurality of R36 are present, the plurality of R36 are mutually the same or different; and
when a plurality of R37 are present, the plurality of R37 are mutually the same or different.
The ring A in the formula (31-3) is also preferably a benzene ring represented by a formula (32) below.
In the formula (32):
one of two ring carbon atoms marked with * is bonded to the bond extending from the ring B in the formula (31-1) or the formula (31-2), and the other ring carbon atom marked with * is bonded to the bond extending from the ring C in the formula (31-3);
R17 represents the same as R1 to R16 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring; and
n is 1 or 2, and when n is 2, two R17 are mutually the same or different.
The compound represented by the formula (31-1) and the formula (31-3) or the compound represented by the formula (31-2) and the formula (31-3) is preferably a compound represented by a formula (33), a formula (34), or a formula (35) below.
In the formulae (33), (34), and (35):
a ring A3 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;
R1 to R7 and R10 to R17 each independently represent the same as R1 to R16 in the formulae (31-1), (31-2), and (31-3); and
two R17 are mutually the same or different.
Also preferably, the substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms as the ring A in the formula (31-3) and the substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms as the ring A3 in the formula (35) are each independently a substituted or unsubstituted fused aryl ring having 10 to 50 ring carbon atoms.
Also preferably, the substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms as the ring A in the formula (31-3) and the substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms as the ring A3 in the formula (35) are each independently a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted anthracene ring, or a substituted or unsubstituted fluorene ring.
Further preferably, the substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms as the ring A in the formula (31-3) and the substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms as the ring A3 in the formula (35) are each independently a substituted or unsubstituted naphthalene ring or a substituted or unsubstituted fluorene ring.
Also preferably, the substituted or unsubstituted heterocycle having 5 to 50 ring carbon atoms as the ring A in the formula (31-3) and the substituted or unsubstituted heterocycle having 5 to 50 ring carbon atoms as the ring A3 in the formula (35) are each independently a substituted or unsubstituted fused heterocycle having 8 to 50 ring atoms.
Also preferably, the substituted or unsubstituted heterocycle having 5 to 50 ring carbon atoms as the ring A in the formula (31-3) and the substituted or unsubstituted heterocycle having 5 to 50 ring carbon atoms as the ring A3 in the formula (35) are each independently a substituted or unsubstituted dibenzofuran ring, a substituted or unsubstituted carbazole ring, or a substituted or unsubstituted dibenzothiophene ring.
The compound represented by the formulae (31-1) and (31-3) or the compound represented by the formulae (31-2) and (31-3) is preferably selected from the group consisting of compounds represented by formulae (36-1) to (36-6) below.
In the formulae (36-1) to (36-6):
R1 to R7 and R10 to R17 each independently represent the same as R1 to R16 in the formula (31-1), the formula (31-2), and the formula (31-3), and two R17 are mutually the same or different;
X is 0, N(R25), or C(R26)(R27);
at least one combination of adjacent two or more of R21 to R27 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 to R27 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring each independently represent the same as R1 to R16 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring in the formula (31-1), the formula (31-2), and the formula (31-3).
In the compound represented by the formula (31-1) and the formula (31-3) or in the compound represented by the formulae (31-2) and (31-3), Ri to R17 are preferably each independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms and a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
In the compound represented by the formulae (31-1) and the formula (31-3) or in the compound represented by the formulae (31-2) and (31-3), Ri to R17 are preferably 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.
The compound represented by the formula (31-1) and the formula (31-3) or the compound represented by the formula (31-2) and the formula (31-3) are each preferably a compound represented by a formula (33-2) below.
In the formula (33-2), R3, R5, R6, R10, R12 and R13 each independently represent the same as R1 to R16 in the formula (31-1), the formula (31-2), and the formula (31-3).
In the compound represented by the formulae (31-1) and the formula (31-3) or in the compound represented by the formulae (31-2) and (31-3), the substituent for “the substituted or unsubstituted” group is preferably selected from the group consisting of an alkyl group having 1 to 50 carbon atoms, an haloalkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, a cycloalkyl group having 3 to 50 ring carbon atoms, an alkoxy group having 1 to 50 carbon atoms, an alkylthio group having 1 to 50 carbon atoms, an aryloxy group having 6 to 50 ring carbon atoms, an arylthio group having 6 to 50 ring carbon atoms, an aralkyl group having 7 to 50 carbon atoms, a group represented by —Si(R341)(R342)(R343), a group represented by —C(═O)R344, a group represented by —COOR345, a group represented by —S(═O)2R646, a group represented by —(═O)(R347)(R348), a group represented by —Ge(R349)(R350)(R351), a group represented by —N(R352)(R353), a hydroxy group, a halogen atom, a cyano group, a nitro group, an aryl group having 6 to 50 ring carbon atoms, and a heterocyclic group having 5 to 50 ring atoms;
R341 to R353 are each independently a hydrogen atom, an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group having 3 to 50 ring carbon atoms, an aryl group having 6 to 50 ring carbon atoms, or a heterocyclic group having 5 to 50 ring atoms;
when a plurality of R341 are present, the plurality of R341 are mutually the same or different;
when a plurality of R342 are present, the plurality of R342 are mutually the same or different;
when a plurality of R343 are present, the plurality of R343 are mutually the same or different;
when a plurality of R344 are present, the plurality of R344 are mutually the same or different;
when a plurality of R345 are present, the plurality of R345 are mutually the same or different;
when a plurality of R346 are present, the plurality of R346 are mutually the same or different;
when a plurality of R347 are present, the plurality of R347 are mutually the same or different;
when a plurality of R348 are present, the plurality of R348 are mutually the same or different;
when a plurality of R349 are present, the plurality of R349 are mutually the same or different;
when a plurality of R350 are present, the plurality of R350 are mutually the same or different;
when a plurality of R351 are present, the plurality of R351 are mutually the same or different;
when a plurality of R352 are present, the plurality of R352 are mutually the same or different; and
when a plurality of R353 are present, the plurality of R353 are mutually the same or different.
In the compound represented by the formula (31-1) and the formula (31-3) or in the compound represented by the formula (31-2) and the formula (31-3), the substituent for “the substituted or unsubstituted” group is preferably an alkyl group having 1 to 50 carbon atoms, an aryl group having 6 to 50 ring carbon atoms, or a heterocyclic group having 5 to 50 ring atoms.
In the compound represented by the formula (31-1) and the formula (31-3) or in the compound represented by the formula (31-2) and the formula (31-3), the substituent for “the substituted or unsubstituted” group is preferably an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 ring carbon atoms, or a heterocyclic group having 5 to 18 ring atoms.
The compound represented by the formula (31-1) and the formula (31-3) or the compound represented by the formula (31-2) and the formula (31-3) are each also preferably a compound represented by a formula (31-11) below.
In the formula (33-11):
at least one combination of adjacent two or more of R1 to R7 and R10 to R16 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;
R1 to R7 and R10 to R16 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring, and R17 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 substituted or unsubstituted alkoxy group having 1 to 50 carbon atoms, a substituted or unsubstituted alkylthio group having 1 to 50 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 50 ring carbon atoms, a substituted or unsubstituted arylthio group having 6 to 50 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a group represented by —Si(R31)(R32)(R33), a group represented by —C(═O)R34, a group represented by —COOR35, a group represented by —N(R36)(R37), 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 R1 to R7 or R10 to R16 is a group represented by —N(R36)(R37);
two R17 are mutually the same or different; and
R31 to R37 each independently represent the same as R31 to R37 in the formulae (31-1), (31-2), and (31-3).
Also preferably, two of R1 to R7 and R10 to R16 in the formula (31-11) are each a group represented by —N(R36)(R37).
The compound represented by the formula (31-11) is also preferably a compound represented by a formula (33-13) below.
In the formula (33-13):
at least one combination of adjacent two or more of R1 to R4 and R10 to R13 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;
R1 to R4 and R10 to R13 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring, and R17 are each independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 5 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having to 18 ring atoms;
two R17 are mutually the same or different; 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.
The compound represented by the formula (31-13) is also preferably a compound represented by a formula (33-14) below.
In the formula (33-14), R17, RA, RB, Rc and RD each independently represent the same as R17, RA, RB, Rc and RD in the formula (33-13), and two R17 are mutually the same or different.
In the formulae (33-13) and (33-14), RA, RB, RC and RD are preferably each independently a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms.
In the formulae (33-13) and (33-14), RA, RB, RC, and RD are preferably each independently a substituted or unsubstituted phenyl group.
In the compound represented by the formula (31-1) and the formula (31-3) or in the compound represented by the formula (31-2) and the formula (31-3), R17 is preferably a hydrogen atom.
In the compounds represented by the formula (31-11), the formula (33-13) and the formula (33-14), the substituent for “the substituted or unsubstituted” group is preferably an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 ring carbon atoms, or a heterocyclic group having 5 to 18 ring atoms.
In the compounds represented by the formula (31-11), the formula (33-13) and the formula (33-14), the substituent for “the substituted or unsubstituted” group is preferably an alkyl group having 1 to 5 carbon atoms.
Specific Examples of Compound Represented by Formulae (31-1) and (31-3) or Compound Represented by Formulae (31-2) and (31-3) Specific examples of the compound represented by the formulae (31-1) and (31-3) or the compound represented by the formulae (31-2) and (31-3) include compounds shown below.
The compound represented by the formula (41) will be described below.
The first emitting compound and the second emitting compound are each also preferably a compound represented by the formula (41) below.
In the formula (41):
a ring a, a ring b and a ring c 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;
R401 and R402 are each independently bonded to the ring a, ring b or ring c to form a substituted or unsubstituted heterocycle, or not bonded thereto to form no substituted or unsubstituted heterocycle; and
R401 and R402 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.
In the compound represented by the formula (41), the ring a, ring b and ring c are each a ring fused with a fused bicyclic structure formed of a boron atom and two nitrogen atoms at the center of the formula (41).
In the compound represented by the formula (41), the “aromatic hydrocarbon ring” for the rings a, b, and c 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 ring a include three carbon atoms on the fused bicyclic structure at the center of the formula (41).
Ring atoms of the “aromatic hydrocarbon ring” for the rings b and c include two carbon atoms on the fused bicyclic structure at the center of the formula (41).
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.
In the compound represented by the formula (41), the “heterocycle” for the rings a, b, and c 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 ring a include three carbon atoms on the fused bicyclic structure at the center of the formula (41).
Ring atoms of the “heterocycle” for the rings b and c include two carbon atoms on the fused bicyclic structure at the center of the formula (41).
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.
In the compound represented by the formula (41), R401 and R402 are optionally each independently bonded with the ring a, ring b, or ring c 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 (41). The heterocycle in the above arrangement optionally includes a hetero atom other than the nitrogen atom. R401 and R402 being bonded with the ring a, ring b, or ring c specifically means that atoms forming R401 and R402 are bonded with atoms forming the ring a, ring b, or ring c. For instance, R401 may be bonded with the ring a to form a bicyclic (or tri-or-more cyclic) fused nitrogen-containing heterocycle, in which the ring including R401 and the ring a 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 R401 bonded with the ring b, R402 bonded with the ring a, and R402 bonded with the ring c.
In an exemplary embodiment, the ring a, ring b and ring c in the formula (41) are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms.
In an exemplary embodiment, the ring a, ring b and ring c in the formula (41) are each independently a substituted or unsubstituted benzene ring or a substituted or unsubstituted naphthalene ring.
In an exemplary embodiment, R401 and R402 in the formula (41) 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 (41) is a compound represented by a formula (42) below.
In the formula (42):
R401A is bonded with at least one of R411 or R421 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R402A is bonded with at least one of R413 or R414 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R401A and R402A 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 R411 to R421 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;
R411 to R421 not forming the substituted or unsubstituted heterocycle and forming neither the substituted or unsubstituted monocyclic ring nor 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 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 monovalent heterocyclic group having 5 to 50 ring atoms; and
R901 to R907 each independently represent the same as R901 to R907 in the compound represented by the formula (2).
R401A and R402A in the formula (42) are groups corresponding to R401 and R402 in the formula (41). For instance, R401A and R411 are optionally bonded with each other to form a bicyclic (or tri-or-more cyclic) fused nitrogen-containing heterocycle, in which the ring including R401A and R411 and a benzene ring corresponding to the ring a 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 R401A bonded with R412, R402A bonded with R413, and R402A bonded with R414.
In the formula (42), at least one combination of adjacent two or more of R411 to R421 may be mutually bonded to form a substituted or unsubstituted monocyclic ring or a substituted or unsubstituted fused ring.
In the formula (42), for instance, R411 and R412 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 R411 and R412, the resultant fused ring forming a naphthalene ring, carbazole ring, indole ring, dibenzofuran ring, or dibenzothiophene ring, respectively.
In an exemplary embodiment, R411 to R421 not contributing to the ring formation in the formula (42) 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, R411 to R421 not contributing to the ring formation in the formula (42) 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, R411 to R421 not contributing to the ring formation in the formula (42) are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, R411 to R421 not contributing to the ring formation in the formula (42) are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, and at least one of R411 to R421 is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, the compound represented by the formula (42) is a compound represented by a formula (43) below.
In the formula (43):
R431 is bonded with R446 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R433 is bonded with R447 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R434 is bonded with R451 to form a substituted or unsubstituted heterocycle, or not bonded therewith to form no substituted or unsubstituted heterocycle;
R441 is bonded with R442 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 R431 to R451 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;
R431 to R451 forming neither the substituted or unsubstituted monocyclic ring nor 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 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
R901 to R907 each independently represent the same as R901 to R907 in the compound represented by the formula (2).
In the formula (43), R431 is optionally bonded with R446 to form a substituted or unsubstituted heterocycle. In the formula (43), for instance, R431 and R446 are optionally bonded with each other to form a tri-or-more cyclic fused nitrogen-containing heterocycle, in which a benzene ring bonded with R446, a ring including a nitrogen atom, and a benzene ring corresponding to the ring a are fused. Specific examples of the nitrogen-containing heterocycle include a compound corresponding to a nitrogen-containing tri(-or-more)cyclic fused heterocyclic group in the specific example group G2. The same applies to R433 bonded with R447, R434 bonded with R451, and R441 bonded with R442.
In an exemplary embodiment, R431 to R451 not contributing to the ring formation in the formula (43) 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, R431 to R451 not contributing to the ring formation in the formula (43) 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, R431 to R451 not contributing to the ring formation in the formula (43) are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms.
In an exemplary embodiment, R431 to R451 not contributing to the ring formation in the formula (43) are each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, and at least one of R431 to R451 is a substituted or unsubstituted alkyl group having 1 to 50 ring carbon atoms.
In an exemplary embodiment, the compound represented by the formula (43) is a compound represented by a formula (43A) below.
In the formula (43A):
R461 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
R462 to R465 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, R461 to R465 in the formula (43A) 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, R461 to R465 in the formula (43A) 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 (43) is a compound represented by a formula (43B) below.
In the formula (43B):
R471 and R472 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,
R473 to R475 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; and
R906 and R907 each independently represent the same as R906 and R907 in the compound represented by the formula (2).
In an exemplary embodiment, the compound represented by the formula (43) is a compound represented by a formula (43B′) below.
In the formula (43B′), R472 to R475 each independently represent the same as R472 to R475 in the compound represented by the formula (43B).
In an exemplary embodiment, at least one of R471 to R475 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, R472 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, and R471 and R473 to R475 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 (43) is a compound represented by a formula (43C) below.
In the formula (43C):
R481 and R482 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; and
R483 to R486 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 (43) is a compound represented by a formula (43C′) below.
In the formula (43C′), R483 to R486 each independently represent the same as R483 to R486 in the compound represented by the formula (43C).
In an exemplary embodiment, R481 to R486 in the formulae (43C) and (43C′) 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, R481 to R486 in the formulae (43C) and (43C′) are each independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
The compound represented by the formula (41) is producible by initially bonding the ring a, ring b and ring c with linking groups (a group including N-R401 and a group including N-R402) to form an intermediate (first reaction), and bonding the ring a, ring b and ring c 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 (41) include compounds below.
The compound represented by the formula (50) will be described below.
The first emitting compound and the second emitting compound are each also preferably a compound represented by the formula (50) below.
In the formula (50):
a ring Ax, a ring Dx, and a ring Ex 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;
X5 is CR55 or a nitrogen atom;
a dashed line extending from X5 is a single bond to Z1 or a single bond to Z2;
Z1 is a carbon atom when bonded to X5 by the single bond represented by the dashed line, and CRx9 or a nitrogen atom when not bonded to X5 by the single bond represented by the dashed line;
Z2 is a carbon atom when bonded to X5 by the single bond represented by the dashed line, and CRx8 or a nitrogen atom when not bonded to X5 by the single bond represented by the dashed line;
a combination of R54 and R55 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;
R54 and R55 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted fluoroalkyl 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(R501)(R502)(R503), a group represented by —O—(R504), a group represented by —S—(R505), a group represented by —N(R506)(R507), a group represented by —C(═O)R508, a group represented by —COOR509, a group represented by —C(═O)-N(R510)(R511), a group represented by —P(═O)(R512)(R513), a cyano 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;
Y is NR51, an oxygen atom, a sulfur atom, or C(R523)(R524), or is represented by the formula (51);
R51 is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted fluoroalkyl 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, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the formula (52);
R51 is bonded to the ring Ax, bonded to the ring Ex, or not bonded to the ring Ax and the ring Ex;
X51 in the formula (52) is CR551 or a nitrogen atom;
a combination of R541 and R551 in the formula (52) 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;
R541 and R551 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring each independently represent the same as R54 to R55 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring;
of two dashed lines in the formula (52), the dashed line extending from X51 is a single bond to Z3 or a single bond to Z4;
the other dashed line represents a bonding position to a nitrogen atom of a group represented by NR51;
Z3 is a carbon atom when bonded to X51 by the single bond represented by the dashed line, and CRX6A or a nitrogen atom when not bonded to X51 by the single bond represented by the dashed line;
Z4 is a carbon atom when bonded to X51 by the single bond represented by the dashed line, and CRX8A or a nitrogen atom when not bonded to X51 by the single bond represented by the dashed line;
a combination of R523 and R524 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;
R521, R522, and R523 and R524 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted fluoroalkyl 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(R501)(R502)(R503), a group represented by —O—(R504), a group represented by —S—(R505), a group represented by —N(R506)(R507), a group represented by —C(═O)R508, a group represented by —COOR509, a group represented by —C(═O)—N(R510)(R511), a group represented by —P(═O)(R512)(R513), a cyano 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 R521 and R522 is bonded to the ring Ax or the ring Ex, or neither R521 nor R522 is bonded to the ring Ax and the ring Ex;
q is 0 or 1;
p and r are each independently 0, 1, 2, or 3;
at least one combination of a combination of adjacent two or more of a plurality of R56, a combination of adjacent two or more of a plurality of R58, a combination of adjacent two or more of a plurality of R59, a combination of RX6A and R56 adjacent to RX6A, a combination of RX9 and R59 adjacent to RX9, a combination of RX8 and R58 adjacent to RX8, and a combination of RX8A and R58 adjacent to RX8A 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
R56, R58, R59, RX6A, RX8A, RX8 and RX9 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted fluoroalkyl 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(R501)(R502)(R503), a group represented by —O—(R504), a group represented by —S—(R505), a group represented by —N(R506)(R507), a group represented by —C(═O)R508, a group represented by —COOR509, a group represented by —C(═O)—N(R510)(R511), a group represented by —P(═O)(R512)(R513), a cyano 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 compound represented by the formula (50), R501 to R513 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 R501 are present, the plurality of R501 are mutually the same or different;
when a plurality of R502 are present, the plurality of R502 are mutually the same or different;
when a plurality of R503 are present, the plurality of R503 are mutually the same or different;
when a plurality of R504 are present, the plurality of R504 are mutually the same or different;
when a plurality of R90s are present, the plurality of R90s are mutually the same or different;
when a plurality of R90s are present, the plurality of R90s are mutually the same or different;
when a plurality of R507 are present, the plurality of R507 are mutually the same or different;
when a plurality of R508 are present, the plurality of R508 are mutually the same or different;
when a plurality of R90s are present, the plurality of R90s are mutually the same or different;
when a plurality of R510 are present, the plurality of R510 are mutually the same or different;
when a plurality of R511 are present, the plurality of R511 are mutually the same or different;
when a plurality of R512 are present, the plurality of R512 are mutually the same or different; and
when a plurality of R513 are present, the plurality of R513 are mutually the same or different.
In the formula (50), the ring Ax, the ring Dx and the ring Ex are also preferably each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring carbon atoms or a substituted or unsubstituted heterocycle having 5 to 30 ring atoms.
In the formula (50), a combination of R54 and R55 also preferably forms a substituted or unsubstituted aliphatic ring.
The compound represented by the formula (50) is also preferably a compound represented by a formula (53) below.
In the formula (53):
at least one combination of a combination of RX1 and RX8A, a combination of RX1 and RX8, a combination of RX2 and RX3, a combination of RX3 and RX4, a combination of RX5 and RX6, and a combination of RX6 and RX5 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;
RX1, RX2, RX3, RX4, RX5, RX6, RX7, RX8A, and RX8 forming neither the substituted or unsubstituted monocyclic ring nor the substituted or unsubstituted fused ring are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted fluoroalkyl 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(R501)(R502)(R503), a group represented by —O—(R504), a group represented by —S—(R905), a group represented by —N(R506)(R507), a group represented by —C(═O)R508, a group represented by —COOR509, a group represented by —C(═O)—N(R510(R511), a group represented by —P(═O)(R512)(R513), a cyano 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;
X5 represents the same as X5 in the formula (50);
R54 represents the same as R54 in the formula (50);
X51 represents the same as X51 in the formula (52); and
R541 represents the same as R541 in the formula (52).
The compound represented by the formula (50) is also preferably a compound represented by a formula (531) below.
In the formula (531):
RX1, RX2, RX3, RX4, RX5, RX6, RX7, RX8A, and RX8 each independently represent the same as RX1, RX2, RX3, RX4, RX5, RX6, RX7, RX8A, and RX8 in the formula (53);
R54 represents the same as R54 in the formula (50); and
R541 represents the same as R541 in the formula (52).
In the formula (531), at least one combination of a combination of RX1 and RX8A, a combination of RX1 and RX8, a combination of RX2 and RX3, a combination of RX3 and RX4, a combination of RX5 and RX6, and a combination of RX6 and RX5 also preferably form a cyclic structure represented by a formula (532) below or a cyclic structure represented by a formula (533) below.
In the formulae (532) and (533):
RV1 to RV8 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms (preferably, a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, more preferably a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms), or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms (preferably, a substituted or unsubstituted aryl group having 6 to 10 ring carbon atoms, more preferably a substituted or unsubstituted aryl group having 6 ring carbon atoms);
W is C(RV9)(RV10), an oxygen atom, a sulfur atom, or NRV11;
RV9 and RV10 are each independently a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms (preferably, a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, more preferably a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms);
RV11 is a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms (preferably, a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, more preferably a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms), or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms (preferably, a substituted or unsubstituted aryl group having 6 to 10 ring carbon atoms, more preferably a substituted or unsubstituted aryl group having 6 ring carbon atoms); and
each * represents a bonding position to the ring Ax, the ring Dx, or the ring Ex.
In the formula (531), R54 and R541 are preferably each independently a methyl group, tert-butyl group, —CF3, unsubstituted phenyl group, β-tert-butylphenyl group, xylyl group or mesityl group.
In the formula (531), RX2, RX3, RX6 and RX7 are preferably each independently a hydrogen atom, a methyl group, ethyl group, isopropyl group, sec-propyl group, n-butyl group, tert-butyl group, -C(Me)2C2H5, unsubstituted phenyl group, β-tert-butylphenyl group, mesityl group, xylyl group, o-methylphenyl group, or substituted or unsubstituted biphenyl group (preferably, unsubstituted biphenyl group).
In the formula (531), RX1, RX8A and RX8 are preferably each independently a hydrogen atom, a methyl group, ethyl group, n-butyl group, unsubstituted phenyl group, —O-phenyl group, —NPh2, N-carbazolyl group or —N(C6H5tBu)2. Ph represents an unsubstituted phenyl group, and tBu represents a tert-butyl group.
In the formula (531), Rx4 and Rx5 are each preferably a hydrogen atom.
In the formula (531), RX4, RX5, RX8A and RX8 are each preferably a hydrogen atom.
The compound represented by the formula (50) is also preferably a compound represented by a formula (534) below.
In the formula (534), RX1, RX2, RX3, RX6, and RX5 each independently represent the same as RX1, RX2, RX3, RX6, and RX5 in the formula (53), R54 represents the same as R54 in the formula (50), and R541 represents the same as R541 in the formula (52).
In the compound represented by the formula (50), R501 to R513 are preferably each independently 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.
Specific examples of the compound represented by the formula (50) include compounds below.
In the organic EL device according to the exemplary embodiment, the second emitting layer may be disposed between the anode and the first emitting layer. In this case, holes are retained at the interface between the emitting layers and the recombination zone is separated from the interface between the emitting layers and the surrounding layers, by appropriately using, each independently, as the first emitting compound and the second emitting compound, at least one compound that is selected from the group consisting of a compound represented by a formula (3) 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 and that at least satisfies the three relationships of the formulae (Numerical Formula 1), (Numerical Formula 3A), and (Numerical Formula 3B). This arrangement is expected to extend the lifetime of the device.
The compound represented by the formula (3) will be described below.
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 first emitting compound and the second emitting compound, 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), two of R301 to R310 are each preferably 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), preferably, Ar3O1 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), preferably, 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), preferably, 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 R335 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.
The compound represented by the formula (4) will be described below.
In the formula (4):
Z are each independently CRa or a nitrogen atom;
a ring A1 and a ring A2 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 ring A1 and the ring A2 in the formula (4) 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 ring A1 and the ring A2 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 ring A1 and the ring A2 in the formula (4) 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 ring A1 and the ring A2 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 in the formula (4) is bonded to any one of carbon atoms forming the aromatic hydrocarbon ring as the ring A1 or any one of atoms forming the heterocycle as the ring A1.
Rc in the formula (4) is bonded to any one of carbon atoms forming the aromatic hydrocarbon ring as the ring A2 or any one of atoms forming the heterocycle as the ring A2.
At least one of Ra, Rb, or Rc in the formula (4) is preferably a group represented by a formula (4a) below. More preferably, at least two of Ra, Rb, or Rc in the formula (4) are each a group represented by the formula (4a).
[Formula 277]
*—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 (42A) below.
In the formula (42A):
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 in the formula (42A) is preferably a group represented by the formula (4a). More preferably, at least two of R401 to R411 in the formula (42A) are each a group represented by the formula (4a).
R404 and R411 in the formula (42A) 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 ring A1.
Further, in an exemplary embodiment, the compound represented by the formula (42A) is a compound formed by bonding a structure represented by the formula (4-1) or the formula (4-2) below to a ring bonded to R404 to R407.
In the formula (4-1), two * are each independently bonded to a ring-forming carbon atom of the aromatic hydrocarbon ring or a ring atom of the heterocycle as the ring A1 in the formula (4) or bonded to one of R404 to R407 in the formula (42A);
in the formula (4-2), three * are each independently bonded to a ring-forming carbon atom of the aromatic hydrocarbon ring or a ring atom of the heterocycle as the ring A1 in the formula (4) or bonded to one of R404 to R407 in the formula (42A);
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):
a ring A1 is defined as in 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 (42A).
In an exemplary embodiment, a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 50 ring carbon atoms as the ring A1 in the formula (41-5) is a substituted or unsubstituted naphthalene ring, or substituted or unsubstituted fluorene ring.
In an exemplary embodiment, a substituted or unsubstituted heterocycle having 5 to 50 ring atoms as the ring A1 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 (42A) 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 (42A);
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, at least one combination of adjacent two or more of R401 to R411 in the compound represented by the formula (42A) are mutually bonded to form a substituted or unsubstituted monocyclic ring, or mutually bonded to form a substituted or unsubstituted fused ring. This exemplary embodiment will be described in detail below as a compound represented by a formula (45) below.
The compound represented by the formula (45) will be described below.
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 mutually bonded to form 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;
the two or more 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 to 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 made of preferably 3 to 7 atoms, 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 the 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 represents the two ring-forming carbon atoms bonded to Rn and Rn+1;
the ring-forming carbon atom bonded to 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 represents the two ring-forming carbon atoms bonded to Rn and Rn+1;
the ring-forming carbon atom bonded to 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 to 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; and
R4512 to R4513, R4515 to R4521 and R4522 to R4525 forming neither the monocyclic ring nor the fused ring, and R4514 each independently represent the same as R461 to R471 in the formula (45).
In the formula (45), preferably, 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, R4515 to R4525 in the formulae (451) to (460) are preferably each independently a group 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, or groups represented by formulae (461) to (464) below.
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.
R901 to R907 in the first emitting compound and the second emitting compound are defined as above.
In an exemplary embodiment, the compound represented by the formula (45) is represented by any 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 any 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 any 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, the substituent is exemplified by 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 any one of formulae (45-22) to (45-25) below.
In the formulae (45-22) to (45-25):
X46 and X47 are each independently G(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 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.
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.
The compound represented by the formula (5) will be described below. The compound represented by the formula (5) corresponds to a compound represented by the formula (41-3) described above.
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;
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; and
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 or R511 to R517 are each a group 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 (52A) below.
In the formula (52A):
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 and 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 (53A) below.
In the formula (53A), R551, R552 and R561 to R564 each independently represent the same as R551, R552 and R561 to R564 in the formula (52A).
In an exemplary embodiment, R561 to R564 in the formulae (52A) and (53A) 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 (52A) and (53A) are each a hydrogen atom.
In an exemplary embodiment, the substituent for the “substituted or unsubstituted” group in the formulae (5), (52A) and (53A) 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.
The compound represented by the formula (6) will be described below.
In the formula (6):
a ring a, a ring b and a ring c 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 ring a, ring b or ring c 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.
In the compound represented by the formula (6), the ring a, ring b and ring c 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).
In the compound represented by the formula (6), the “aromatic hydrocarbon ring” for the rings a, b, and c 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 ring a 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 rings b and c 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.
In the compound represented by the formula (6), the “heterocycle” for the rings a, b, and c 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 ring a include three carbon atoms on the fused bicyclic structure at the center of the formula (6). Ring atoms of the “heterocycle” for the rings b and c 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 may be each independently bonded with the ring a, ring b, or ring c 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 being bonded with the ring a, ring b, or ring c specifically means that atoms forming R601 and R602 are bonded with atoms forming the ring a, ring b, or ring c. For instance, R601 may be bonded with the ring a to form a bicyclic (or tri-or-more cyclic) fused nitrogen-containing heterocycle, in which the ring including R601 and the ring a 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 R601 bonded with the ring b, R602 bonded with the ring a, and R602 bonded with the ring c.
In an exemplary embodiment, the ring a, ring b and ring c 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 ring a, ring b and ring c in the formula (6) are each independently a substituted or unsubstituted benzene ring or a substituted or unsubstituted naphthalene ring.
In the 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 ring a 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 are optionally mutually bonded to form a substituted or unsubstituted monocyclic ring or 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.
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 is 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 ring a are fused. Specific examples of the nitrogen-containing heterocycle include a compound corresponding to a 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; and 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; and
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 carbon atoms.
The compound represented by the formula (6) is producible by initially bonding the ring a, ring b and ring c with linking groups (a group including N-R601 and a group including N-R602) to form an intermediate (first reaction), and bonding the ring a, ring b and ring c 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.
The compound represented by the formula (7) will be described below.
In the formula (7):
a ring r is a ring represented by the formula (72) or the formula (73), the ring r being fused with adjacent ring(s) at any position(s);
a ring q and a ring s are each independently a ring represented by the formula (74) and fused with adjacent ring(s) at any position(s);
a ring p and a ring t 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 forming neither the monocyclic ring nor the fused ring and R702 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 ring p, ring q, ring r, ring s, and ring t 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 ring r, 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, L701, m1, m3 and m4 respectively represent the same as R701, X7, Ar701, Ar702, L701, 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.
The compound represented by the formula (8) will be described below.
In the formula (8):
at least one combination of a combination of R801 and R802, a combination of R802 and R803, and a combination of R803 and R804 are mutually bonded to form a divalent group represented by a formula (82) below; and
at least one combination of a combination of R805 and R806, a combination of R806 and R807, and a combination of 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 R811 to R814 is a monovalent group represented by a formula (84) below;
at least one of R80s to R80s not forming the divalent group represented by the formula (83) or R821 to R824 is a monovalent group represented by the 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 R80s 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 not being 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);
* i a single bond bonded to a monovalent group represented by the formula (84); and 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 (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.
The compound represented by the formula (9) will be described below.
In the formula (9):
a ring A51 and a A92 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 the ring A91 or the ring A92 is bonded with * in a structure represented by a formula (92) below.
In the formula (92):
a ring A93 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(R54)(R98), Si(R96)(R97), Ge(R98)(R99), an oxygen atom, a sulfur atom, or a selenium atom;
R51 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 forming neither the monocyclic ring nor 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 of the ring A91 or the ring A92 is bonded to * in 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 ring A91 in an exemplary embodiment are bonded to * 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 ring A92 in an exemplary embodiment are bonded to * 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 ring A91 and the ring A92.
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 the ring A91 and the ring A92.
In an exemplary embodiment, in addition to the ring A91, the ring-forming carbon atoms of the aromatic hydrocarbon ring or the ring atoms of the heterocycle of the ring A92 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 ring A91 and the ring 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.
The compound represented by the formula (10) will be described below.
In the formula (10):
a ring Ax1 is a ring represented by the formula (10a) that is fused with adjacent ring(s) at any position(s);
a ring Ax2 is a ring represented by the formula (10b) that is fused with adjacent ring(s) at any position(s);
two * in the formula (10b) are bonded to a ring Ax3 at any position(s);
XA and XB are each independently C(R1003)(R1004), Si(R1005)(R1006), an oxygen atom or a sulfur atom;
the ring Ax3 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, and mx2 is 2;
a plurality of R1101 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, the ring Ax3 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.
In an exemplary embodiment, the 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 R904a are present, the two or more R904a 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, the substituent for “the substituted or unsubstituted” group in each of the above 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, the substituent for “the substituted or unsubstituted” group in each of the above 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.
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 display component (e.g., an organic EL panel module), TV, mobile phone, tablet and personal computer. 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, the number of emitting layers is not limited to two, and more than two emitting layers may be layered. When the organic EL device includes more than two emitting layers, it is only necessary that at least two of the emitting layers should satisfy the requirements mentioned in the above exemplary embodiments. For instance, the rest of the emitting layers may be a fluorescent emitting layer or a phosphorescent emitting layer with use of emission caused by electron transfer from the triplet excited state directly to the ground state.
When the organic EL device includes a plurality of emitting layers, these emitting layers may be mutually adjacently provided, or may form a so-called tandem organic EL device, in which a plurality of emitting units are layered via an intermediate layer.
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 or excitons.
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 the 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. The scope of the invention is by no means limited to Examples.
Structures of compounds used for producing organic EL devices in Example 1 and Comparative Examples 1 to 2 are shown below.
A glass substrate (size: 25 mm×75 mm×1.1 mm thick, produced 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. The film thickness of the ITO transparent electrode was 130 nm.
After the glass substrate having the transparent electrode line was cleaned, the glass substrate was mounted on a substrate holder of a vacuum deposition apparatus. Firstly, a compound HA was vapor-deposited on a surface of the glass substrate where the transparent electrode line was provided in a manner to cover the transparent electrode, thereby forming a 5-nm-thick hole injecting layer.
A compound HT-a was vapor-deposited on this formed hole injecting layer to form a 125-nm-thick hole transporting layer.
A compound EB-a was vapor-deposited on the hole transporting layer to form a 15-nm-thick electron blocking layer (EBL).
A compound BH1-a (first host material (BH)) and a compound BD1-a (first emitting compound) were co-deposited on the electron blocking layer such that the ratio of the compound BD1-a accounted for 1 mass %, thereby forming a 12.5-nm-thick first emitting layer.
A compound BH2-a (second host material (BH)) and the compound BD1-a (second emitting compound) were co-deposited on the first emitting layer such that the ratio of the compound BD1-a accounted for 1 mass %, thereby forming a 12.5-nm-thick second emitting layer.
A compound HB-a was vapor-deposited on the second emitting layer to form a 5-nm-thick hole blocking layer (HBL).
A compound ET-a was vapor-deposited on the hole blocking layer to form a 20-nm-thick electron transporting layer (ET).
Lithium fluoride (LiF) was vapor-deposited on the electron transporting layer to form a 0.5-nm-thick electron injecting layer.
Metal Al was vapor-deposited on the electron injecting layer to form a 150-nm-thick cathode.
A device arrangement of the organic EL device in Example 1 is roughly shown as follows.
ITO(130)/HA(5)/HT-a(125)/EB-a(15)/BH1-a:BD1-a(12.5,99%:1%)/BH2-a:BD1-a(12.5,99%:1%)/HB-a(5)/ET-a(20)/LiF(0.5)/AI(150)
Numerals in parentheses represent a film thickness (unit: nm).
Similarly, numerals (99%:1%) expressed in percentages in parentheses indicate the ratios (mass %) of the host material (compound BH1-a or BH2-a) and the emitting compound (compound BD1-a) in the first emitting layer or the second emitting layer.
An organic EL device of Comparative Example 1 was produced in the same manner as in Example 1 except that the compound BD1-a (emitting compound) used in the first emitting layer and the second emitting layer in Example 1 was replaced by a compound shown in Table 1.
An organic EL device of Comparative Example 2 was produced in the same manner as in Example 1 except that the compound BH2-a and the compound BD1-a were co-deposited on the electron blocking layer such that the ratio of the compound BD1-a accounted for 1 mass % to form a 25-nm-thick second emitting layer.
The produced organic EL devices were evaluated as follows. Table 1 shows the evaluation results. Table 1 also shows the HOMO, LUMO, singlet energy S1 and triplet energy T1 of the first host material, the second host material, the first emitting compound and the second emitting compound.
Voltage was applied to the organic EL device such that a current density was 10 mA/cm2, where spectral radiance spectrum was measured by a spectroradiometer CS-2000 (produced by Konica Minolta, Inc.). The external quantum efficiency FE (unit: %) was calculated based on the obtained spectral radiance spectra, assuming that the spectra were provided under a Lambertian radiation.
Voltage was applied to the produced organic EL device such that a current density was 50 mA/cm2, where a time (LT95 (unit: hr)) elapsed before a luminance intensity was reduced to 95% of the initial luminance intensity was measured. The luminance intensity was measured by using a spectroradiometer 8S-2000 (produced by Konica Minolta, Inc.).
The organic EL device of Example 1 satisfied the relationships of the formulae (Numerical Formula 1), (Numerical Formula 2A) and (Numerical Formula 2B), whereas the organic EL device of Comparative Example 1 did not satisfy the relationship of the formula (Numerical Formula 2B). The organic EL device of Example 1 had a longer lifetime than the organic EL device of Comparative Example 1.
Example 1 and Comparative Example 1 had the first emitting layer and the second emitting layer satisfying the relationship of the formula (Numerical Formula 1), whereas the organic EL device of Comparative Example 2 did not have the first emitting layer. The organic EL devices of Example 1 and Comparative Example 1 emitted light with a higher efficiency than the organic EL device of Comparative Example 2.
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 may have an error of about plus or minus 0.02 eV depending on measurement conditions.
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 produced 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 singlet energy.
A spectrophotometer (U3310 produced 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.
An energy level of a highest occupied molecular orbital HOMO was measured under atmosphere using a photoelectron spectroscope (“AC-3” produced by RIKEN KEIKI Co., Ltd.). Specifically, the material was irradiated with light and the amount of electrons generated by charge separation was measured to measure the energy level of the highest occupied molecular orbital HOMO of the compound.
Herein, the energy level of the lowest unoccupied molecular orbital LUMO is a value calculated by an equation (Numerical Formula 1X) below on the basis of measured values of the energy level of the highest occupied molecular orbital HOMO and the singlet energy Si.
Measurement of Maximum Fluorescence Peak Wavelength (FL-peak) 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 produced 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 A (unit: nm) was measured.
The maximum fluorescence peak wavelength A of the compound BD1-a was 457 nm.
The maximum fluorescence peak wavelength A of the compound BD2-a was 453 nm.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-094719 | Jun 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/022511 | 6/2/2022 | WO |
