Patent Application
20250234771
The present invention relates to a compound, a material for organic electroluminescent device, an organic electroluminescent device, and an electronic device containing the organic electroluminescent device.
In general, an organic electroluminescent device (hereinafter referred to as “organic EL device”) is constituted by an anode, a cathode, and an organic layer sandwiched between the anode and cathode. When a voltage is applied between the two electrodes, electrons are injected from the cathode side and holes are injected from the anode side into the light emitting region, and the injected electrons and holes recombine in the light emitting region to generate an excited state, and when the state returns to the ground state, the light is emitted. Therefore, the development of materials which efficiently transport electrons or holes to the light emitting region and facilitate the recombination of electrons and holes is important in obtaining a high-performance organic EL device.
Patent Literatures 1 to 5 disclose compounds used as a material for organic electroluminescent device.
Although many compounds for organic EL devices have been reported until now, there is still a need for compounds which further improve the performance of organic EL devices.
The present invention was made to solve the above problems, and the object is to provide a compound which further improves the performance of an organic EL device, an organic EL device with further improved element performance, and an electronic device including such an organic EL device.
As a result of extensive research about the performance of organic EL devices containing the compounds described in Patent Literatures 1 to 4, the inventors found that an organic EL device containing a compound represented by any of the following formulas (1) to (3) has more improved performance.
In one embodiment, the present invention provides a compound represented by the following formula (1),
(In the formula, N* is a central nitrogen atom,
In another embodiment, the present invention provides a compound represented by the following formula (2),
(In the formula, N* is a central nitrogen atom,
In another embodiment, the present invention provides a compound represented by the following formula (3),
(In the formula, N* is a central nitrogen atom,
Provided that two adjacent ones selected from Ra31 to Ra48 which are not a single bond bonded to *12 may be bonded to each other to form a benzene ring, or may not be bonded to each other and therefore may not form a ring,
In another embodiment, the present invention provides a material for organic EL device containing a compound represented by any of the above formulas (1) to (3).
Further, in another embodiment, the present invention provides an organic electroluminescent device containing a cathode, an anode, and an organic layer between the cathode and the anode, in which the organic layer contains a light emitting layer, and at least one layer of the organic layers contains the compound represented by the above formulas (1) to (3).
Furthermore, in another embodiment, the present invention provides an electronic device containing the organic electroluminescent device.
An organic EL device containing a compound represented by any one of the above formulas (1) to (3) exhibits improved device performance.
In the description herein, the hydrogen atom encompasses isotopes thereof having different numbers of neutrons, i.e., a light hydrogen atom (protium), a heavy hydrogen atom (deuterium), and tritium.
In the description herein, the bonding site where the symbol, such as “R”, or “D” representing a deuterium atom is not shown is assumed to have a hydrogen atom, i.e., a protium atom, a deuterium atom, or a tritium atom, bonded thereto.
In the description herein, the number of ring carbon atoms shows the number of carbon atoms among the atoms constituting the ring itself of a compound having a structure including atoms bonded to form a ring (such as a monocyclic compound, a condensed ring compound, a bridged compound, a carbocyclic compound, and a heterocyclic compound). In the case where the ring is substituted by a substituent, the carbon atom contained in the substituent is not included in the number of ring carbon atoms. The same definition is applied to the “number of ring carbon atoms” described hereinafter unless otherwise indicated. For example, 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. For example, 9,9-diphenylfluorenyl group has 13 ring carbon atoms, and 9,9′-spirobifluorenyl group has 25 ring carbon atoms.
In the case where a benzene ring has, for example, an alkyl group substituted thereon as a substituent, the number of carbon atoms of the alkyl group is not included in the number of ring carbon atoms of the benzene ring. Accordingly, a benzene ring having an alkyl group substituted thereon has 6 ring carbon atoms. In the case where a naphthalene ring has, for example, an alkyl group substituted thereon as a substituent, the number of carbon atoms of the alkyl group is not included in the number of ring carbon atoms of the naphthalene ring. Accordingly, a naphthalene ring having an alkyl group substituted thereon has 10 ring carbon atoms.
In the description herein, the number of ring atoms shows the number of atoms constituting the ring itself of a compound having a structure including atoms bonded to form a ring (such as a monocyclic ring, a condensed ring, and a set of rings) (such as a monocyclic compound, a condensed ring compound, a bridged compound, a carbocyclic compound, and a heterocyclic compound). The atom that does not constitute the ring (such as a hydrogen atom terminating the bond of the atom constituting the ring) and, in the case where the ring is substituted by a substituent, the atom contained in the substituent are not included in the number of ring atoms. The same definition is applied to the “number of ring atoms” described hereinafter unless otherwise indicated. For example, a pyridine ring has 6 ring atoms, a quinazoline ring has 10 ring atoms, and a furan ring has 5 ring atoms. For example, the number of hydrogen atoms bonded to a pyridine ring or atoms constituting a substituent is not included in the number of ring atoms of the pyridine ring. Accordingly, a pyridine ring having a hydrogen atom or a substituent bonded thereto has 6 ring atoms. For example, the number of hydrogen atoms bonded to carbon atoms of a quinazoline ring or atoms constituting a substituent is not included in the number of ring atoms of the quinazoline ring. Accordingly, a quinazoline ring having a hydrogen atom or a substituent bonded thereto has 10 ring atoms.
In the description herein, the expression “having XX to YY carbon atoms” in the expression “substituted or unsubstituted ZZ group having XX to YY carbon atoms” means the number of carbon atoms of the unsubstituted ZZ group, and, in the case where the ZZ group is substituted, the number of carbon atoms of the substituent is not included. Herein, “YY” is larger than “XX”, “XX” represents an integer of 1 or more, and “YY” represents an integer of 2 or more.
In the description herein, the expression “having XX to YY atoms” in the expression “substituted or unsubstituted ZZ group having XX to YY atoms” means the number of atoms of the unsubstituted ZZ group, and, in the case where the ZZ group is substituted, the number of atoms of the substituent is not included. Herein, “YY” is larger than “XX”, “XX” represents an integer of 1 or more, and “YY” represents an integer of 2 or more.
In the description herein, an unsubstituted ZZ group means the case where the “substituted or unsubstituted ZZ group” is an “unsubstituted ZZ group”, and a substituted ZZ group means the case where the “substituted or unsubstituted ZZ group” is a “substituted ZZ group”.
In the description herein, the expression “unsubstituted” in the expression “substituted or unsubstituted ZZ group” means that hydrogen atoms in the ZZ group are not substituted by a substituent. The hydrogen atoms in the “unsubstituted ZZ group” each are a protium atom, a deuterium atom, or a tritium atom.
In the description herein, the expression “substituted” in the expression “substituted or unsubstituted ZZ group” means that one or more hydrogen atom in the ZZ group is substituted by a substituent. The expression “substituted” in the expression “BB group substituted by an AA group” similarly means that one or more hydrogen atom in the BB group is substituted by the AA group.
The substituents described in the description herein will be explained.
In the description herein, the number of ring carbon atoms of the “unsubstituted aryl group” is 6 to 50, preferably 6 to 30, and more preferably 6 to 18, unless otherwise indicated in the description.
In the description herein, the number of ring atoms of the “unsubstituted heterocyclic group” is 5 to 50, preferably 5 to 30, and more preferably 5 to 18, unless otherwise indicated in the description.
In the description herein, the number of carbon atoms of the “unsubstituted alkyl group” is 1 to 50, preferably 1 to 20, and more preferably 1 to 6, unless otherwise indicated in the description.
In the description herein, the number of carbon atoms of the “unsubstituted alkenyl group” is 2 to 50, preferably 2 to 20, and more preferably 2 to 6, unless otherwise indicated in the description.
In the description herein, the number of carbon atoms of the “unsubstituted alkynyl group” is 2 to 50, preferably 2 to 20, and more preferably 2 to 6, unless otherwise indicated in the description.
In the description herein, the number of ring carbon atoms of the “unsubstituted cycloalkyl group” is 3 to 50, preferably 3 to 20, and more preferably 3 to 6, unless otherwise indicated in the description.
In the description herein, the number of ring carbon atoms of the “unsubstituted arylene group” is 6 to 50, preferably 6 to 30, and more preferably 6 to 18, unless otherwise indicated in the description.
In the description herein, the number of ring atoms of the “unsubstituted divalent heterocyclic group” is 5 to 50, preferably 5 to 30, and more preferably 5 to 18, unless otherwise indicated in the description.
In the description herein, the number of carbon atoms of the “unsubstituted alkylene group” is 1 to 50, preferably 1 to 20, and more preferably 1 to 6, unless otherwise indicated in the description.
In the description herein, specific examples (set of specific examples G1) of the “substituted or unsubstituted aryl group” include the unsubstituted aryl groups (set of specific examples G1A) and the substituted aryl groups (set of specific examples G1B) shown below. (Herein, the unsubstituted aryl group means the case where the “substituted or unsubstituted aryl group” is an “unsubstituted aryl group”, and the substituted aryl group means the case where the “substituted or unsubstituted aryl group” is a “substituted aryl group”.) In the description herein, the simple expression “aryl group” encompasses both the “unsubstituted aryl group” and the “substituted aryl group”.
The “substituted aryl group” means a group formed by substituting one or more hydrogen atom of the “unsubstituted aryl group” by a substituent. Examples of the “substituted aryl group” include groups formed by one or more hydrogen atom of each of the “unsubstituted aryl groups” in the set of specific examples G1A by a substituent, and the examples of the substituted aryl groups in the set of specific examples G1B. The examples of the “unsubstituted aryl group” and the examples of the “substituted aryl group” enumerated herein are mere examples, and the “substituted aryl group” in the description herein encompasses groups formed by substituting a hydrogen atom bonded to the carbon atom of the aryl group itself of each of the “substituted aryl groups” in the set of specific examples G1B by a substituent, and groups formed by substituting a hydrogen atom of the substituent of each of the “substituted aryl groups” in the set of specific examples G1B by a substituent.
In the description herein, the “heterocyclic group” means a cyclic group containing at least one hetero atom in the ring atoms. Specific examples of the hetero atom include a nitrogen atom, an oxygen atom, a sulfur atom, a silicon atom, a phosphorus atom, and a boron atom.
In the description herein, the “heterocyclic group” is a monocyclic group or a condensed ring group.
In the description herein, the “heterocyclic group” is an aromatic heterocyclic group or a non-aromatic heterocyclic group.
In the description herein, specific examples (set of specific examples G2) of the “substituted or unsubstituted heterocyclic group” include the unsubstituted heterocyclic groups (set of specific examples G2A) and the substituted heterocyclic groups (set of specific examples G2B) shown below: (Herein, the unsubstituted heterocyclic group means the case where the “substituted or unsubstituted heterocyclic group” is an “unsubstituted heterocyclic group”, and the substituted heterocyclic group means the case where the “substituted or unsubstituted heterocyclic group” is a “substituted heterocyclic group”.) In the description herein, the simple expression “heterocyclic group” encompasses both the “unsubstituted heterocyclic group” and the “substituted heterocyclic group”.
The “substituted heterocyclic group” means a group formed by substituting one or more hydrogen atom of the “unsubstituted heterocyclic group” by a substituent. Specific examples of the “substituted heterocyclic group” include groups formed by substituting a hydrogen atom of each of the “unsubstituted heterocyclic groups” in the set of specific examples G2A by a substituent, and the examples of the substituted heterocyclic groups in the set of specific examples G2B. The examples of the “unsubstituted heterocyclic group” and the examples of the “substituted heterocyclic group” enumerated herein are mere examples, and the “substituted heterocyclic group” in the description herein encompasses groups formed by substituting a hydrogen atom bonded to the ring atom of the heterocyclic group itself of each of the “substituted heterocyclic groups” in the set of specific examples G2B by a substituent, and groups formed by substituting a hydrogen atom of the substituent of each of the “substituted heterocyclic groups” in the set of specific examples G2B by a substituent.
The set of specific examples G2A includes, for example, the unsubstituted heterocyclic group containing a nitrogen atom (set of specific examples G2A1), the unsubstituted heterocyclic group containing an oxygen atom (set of specific examples G2A2), the unsubstituted heterocyclic group containing a sulfur atom (set of specific examples G2A3), and monovalent heterocyclic groups derived by removing one hydrogen atom from each of the ring structures represented by the following general formulae (TEMP-16) to (TEMP-33) (set of specific examples G2A4).
The set of specific examples G2B includes, for example, the substituted heterocyclic groups containing a nitrogen atom (set of specific examples G2B1), the substituted heterocyclic groups containing an oxygen atom (set of specific examples G2B2), the substituted heterocyclic groups containing a sulfur atom (set of specific examples G2B3), and groups formed by substituting one or more hydrogen atom of each of monovalent heterocyclic groups derived from the ring structures represented by the following general formulae (TEMP-16) to (TEMP-33) by a substituent (set of specific examples G2B4).
Monovalent Heterocyclic Group derived by removing One Hydrogen Atom from Ring Structures represented by General Formulae (TEMP-16) to (TEMP-33) (Set of Specific Examples G2A4)
In the general formulae (TEMP-16) to (TEMP-33), XA and YA each independently represent an oxygen atom, a sulfur atom, NH, or CH2, provided that at least one of XA and YA represents an oxygen atom, a sulfur atom, or NH.
In the general formulae (TEMP-16) to (TEMP-33), in the case where at least one of XA and YA represents NH or CH2, the monovalent heterocyclic groups derived from the ring structures represented by the general formulae (TEMP-16) to (TEMP-33) include monovalent groups formed by removing one hydrogen atom from the NH or CH2.
Substituted Heterocyclic Group containing Nitrogen Atom (Set of Specific Examples G2B1):
Group formed by substituting one or more Hydrogen Atom of Monovalent Heterocyclic Group derived from Ring Structures represented by General Formulae (TEMP-16) to (TEMP-33) by Substituent (Set of Specific Examples G2B4)
The “one or more hydrogen atom of the monovalent heterocyclic group” means one or more hydrogen atom selected from the hydrogen atom bonded to the ring carbon atom of the monovalent heterocyclic group, the hydrogen atom bonded to the nitrogen atom in the case where at least one of XA and YA represents NH, and the hydrogen atom of the methylene group in the case where one of XA and YA represents CH2.
In the description herein, specific examples (set of specific examples G3) of the “substituted or unsubstituted alkyl group” include the unsubstituted alkyl groups (set of specific examples G3A) and the substituted alkyl groups (set of specific examples G3B) shown below. (Herein, the unsubstituted alkyl group means the case where the “substituted or unsubstituted alkyl group” is an “unsubstituted alkyl group”, and the substituted alkyl group means the case where the “substituted or unsubstituted alkyl group” is a “substituted alkyl group”.) In the description herein, the simple expression “alkyl group” encompasses both the “unsubstituted alkyl group” and the “substituted alkyl group”.
The “substituted alkyl group” means a group formed by substituting one or more hydrogen atom of the “unsubstituted alkyl group” by a substituent. Specific examples of the “substituted alkyl group” include groups formed by substituting one or more hydrogen atom of each of the “unsubstituted alkyl groups” (set of specific examples G3A) by a substituent, and the examples of the substituted alkyl groups (set of specific examples G3B). In the description herein, the alkyl group in the “unsubstituted alkyl group” means a chain-like alkyl group. Accordingly, the “unsubstituted alkyl group” encompasses an “unsubstituted linear alkyl group” and an “unsubstituted branched alkyl group”. The examples of the “unsubstituted alkyl group” and the examples of the “substituted alkyl group” enumerated herein are mere examples, and the “substituted alkyl group” in the description herein encompasses groups formed by substituting a hydrogen atom of the alkyl group itself of each of the “substituted alkyl groups” in the set of specific examples G3B by a substituent, and groups formed by substituting a hydrogen atom of the substituent of each of the “substituted alkyl groups” in the set of specific examples G3B by a substituent.
In the description herein, specific examples (set of specific examples G4) of the “substituted or unsubstituted alkenyl group” include the unsubstituted alkenyl groups (set of specific examples G4A) and the substituted alkenyl groups (set of specific examples G4B) shown below. (Herein, the unsubstituted alkenyl group means the case where the “substituted or unsubstituted alkenyl group” is an “unsubstituted alkenyl group”, and the substituted alkenyl group means the case where the “substituted or unsubstituted alkenyl group” is a “substituted alkenyl group”.) In the description herein, the simple expression “alkenyl group” encompasses both the “unsubstituted alkenyl group” and the “substituted alkenyl group”.
The “substituted alkenyl group” means a group formed by substituting one or more hydrogen atom of the “unsubstituted alkenyl group” by a substituent. Specific examples of the “substituted alkenyl group” include the “unsubstituted alkenyl groups” (set of specific examples G4A) that each have a substituent, and the examples of the substituted alkenyl groups (set of specific examples G4B). The examples of the “unsubstituted alkenyl group” and the examples of the “substituted alkenyl group” enumerated herein are mere examples, and the “substituted alkenyl group” in the description herein encompasses groups formed by substituting a hydrogen atom of the alkenyl group itself of each of the “substituted alkenyl groups” in the set of specific examples G4B by a substituent, and groups formed by substituting a hydrogen atom of the substituent of each of the “substituted alkenyl groups” in the set of specific examples G4B by a substituent.
In the description herein, specific examples (set of specific examples G5) of the “substituted or unsubstituted alkynyl group” include the unsubstituted alkynyl group (set of specific examples G5A) shown below. (Herein, the unsubstituted alkynyl group means the case where the “substituted or unsubstituted alkynyl group” is an “unsubstituted alkynyl group”.) In the description herein, the simple expression “alkynyl group” encompasses both the “unsubstituted alkynyl group” and the “substituted alkynyl group”. The “substituted alkynyl group” means a group formed by substituting one or more hydrogen atom of the “unsubstituted alkynyl group” by a substituent. Specific examples of the “substituted alkenyl group” include groups formed by substituting one or more hydrogen atom of the “unsubstituted alkynyl group” (set of specific examples G5A) by a substituent.
In the description herein, specific examples (set of specific examples G6) of the “substituted or unsubstituted cycloalkyl group” include the unsubstituted cycloalkyl groups (set of specific examples G6A) and the substituted cycloalkyl group (set of specific examples G6B) shown below: (Herein, the unsubstituted cycloalkyl group means the case where the “substituted or unsubstituted cycloalkyl group” is an “unsubstituted cycloalkyl group”, and the substituted cycloalkyl group means the case where the “substituted or unsubstituted cycloalkyl group” is a “substituted cycloalkyl group”.) In the description herein, the simple expression “cycloalkyl group” encompasses both the “unsubstituted cycloalkyl group” and the “substituted cycloalkyl group”.
The “substituted cycloalkyl group” means a group formed by substituting one or more hydrogen atom of the “unsubstituted cycloalkyl group” by a substituent. Specific examples of the “substituted cycloalkyl group” include groups formed by substituting one or more hydrogen atom of each of the “unsubstituted cycloalkyl groups” (set of specific examples G6A) by a substituent, and the example of the substituted cycloalkyl group (set of specific examples G6B). The examples of the “unsubstituted cycloalkyl group” and the examples of the “substituted cycloalkyl group” enumerated herein are mere examples, and the “substituted cycloalkyl group” in the description herein encompasses groups formed by substituting one or more hydrogen atom bonded to the carbon atoms of the cycloalkyl group itself of the “substituted cycloalkyl group” in the set of specific examples G6B by a substituent, and groups formed by substituting a hydrogen atom of the substituent of the “substituted cycloalkyl group” in the set of specific examples G6B by a substituent.
In the description herein, specific examples (set of specific examples G7) of the group represented by —Si(R901)(R902)(R903) include:
Plural groups represented by G1 in —Si(G1)(G1)(G1) are the same as or different from each other.
Plural groups represented by G2 in —Si(G1)(G2)(G2) are the same as or different from each other.
Plural groups represented by G1 in —Si(G1)(G1)(G2) are the same as or different from each other.
Plural groups represented by G2 in —Si(G2)(G2)(G2) are the same as or different from each other.
Plural groups represented by G3 in —Si(G3)(G3)(G3) are the same as or different from each other.
Plural groups represented by G6 in —Si(G6)(G6)(G6) are the same as or different from each other.
In the description herein, specific examples (set of specific examples G8) of the group represented by —O—(R904) include:
Herein,
In the description herein, specific examples (set of specific examples G9) of the group represented by —S—(R905) include:
Herein,
In the description herein, specific examples (set of specific examples G10) of the group represented by —N(R906)(R907) include:
Herein,
Plural groups represented by G1 in —N(G1)(G1) are the same as or different from each other.
Plural groups represented by G2 in —N(G2)(G2) are the same as or different from each other.
Plural groups represented by G3 in —N(G3)(G3) are the same as or different from each other.
Plural groups represented by G6 in —N(G6)(G6) are the same as or different from each other.
In the description herein, specific examples (set of specific examples G11) of the “halogen atom” include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
In the description herein, the “substituted or unsubstituted fluoroalkyl group” means a group formed by substituting at least one hydrogen atom bonded to the carbon atom constituting the alkyl group in the “substituted or unsubstituted alkyl group” by a fluorine atom, and encompasses a group formed by substituting all the hydrogen atoms bonded to the carbon atoms constituting the alkyl group in the “substituted or unsubstituted alkyl group” by fluorine atoms (i.e., a perfluoroalkyl group). The number of carbon atoms of the “unsubstituted fluoroalkyl group” is 1 to 50, preferably 1 to 30, and more preferably 1 to 18, unless otherwise indicated in the description. The “substituted fluoroalkyl group” means a group formed by substituting one or more hydrogen atom of the “fluoroalkyl group” by a substituent. In the description herein, the “substituted fluoroalkyl group” encompasses a group formed by substituting one or more hydrogen atom bonded to the carbon atom of the alkyl chain in the “substituted fluoroalkyl group” by a substituent, and a group formed by substituting one or more hydrogen atom of the substituent in the “substituted fluoroalkyl group” by a substituent. Specific examples of the “unsubstituted fluoroalkyl group” include examples of groups formed by substituting one or more hydrogen atom in each of the “alkyl group” (set of specific examples G3) by a fluorine atom.
In the description herein, the “substituted or unsubstituted haloalkyl group” means a group formed by substituting at least one hydrogen atom bonded to the carbon atom constituting the alkyl group in the “substituted or unsubstituted alkyl group” by a halogen atom, and encompasses a group formed by substituting all the hydrogen atoms bonded to the carbon atoms constituting the alkyl group in the “substituted or unsubstituted alkyl group” by halogen atoms. The number of carbon atoms of the “unsubstituted haloalkyl group” is 1 to 50, preferably 1 to 30, and more preferably 1 to 18, unless otherwise indicated in the description. The “substituted haloalkyl group” means a group formed by substituting one or more hydrogen atom of the “haloalkyl group” by a substituent. In the description herein, the “substituted haloalkyl group” encompasses a group formed by substituting one or more hydrogen atom bonded to the carbon atom of the alkyl chain in the “substituted haloalkyl group” by a substituent, and a group formed by substituting one or more hydrogen atom of the substituent in the “substituted haloalkyl group” by a substituent. Specific examples of the “unsubstituted haloalkyl group” include examples of groups formed by substituting one or more hydrogen atom in each of the “alkyl group” (set of specific examples G3) by a halogen atom. A haloalkyl group may be referred to as a halogenated alkyl group in some cases.
In the description herein, specific examples of the “substituted or unsubstituted alkoxy group” include a group represented by —O(G3), wherein G3 represents the “substituted or unsubstituted alkyl group” described in the set of specific examples G3. The number of carbon atoms of the “unsubstituted alkoxy group” is 1 to 50, preferably 1 to 30, and more preferably 1 to 18, unless otherwise indicated in the description.
In the description herein, specific examples of the “substituted or unsubstituted alkylthio group” include a group represented by —S(G3), wherein G3 represents the “substituted or unsubstituted alkyl group” described in the set of specific examples G3. The number of carbon atoms of the “unsubstituted alkylthio group” is 1 to 50, preferably 1 to 30, and more preferably 1 to 18, unless otherwise indicated in the description.
In the description herein, specific examples of the “substituted or unsubstituted aryloxy group” include a group represented by —O(G1), wherein G1 represents the “substituted or unsubstituted aryl group” described in the set of specific examples G1. The number of ring carbon atoms of the “unsubstituted aryloxy group” is 6 to 50, preferably 6 to 30, and more preferably 6 to 18, unless otherwise indicated in the description.
In the description herein, specific examples of the “substituted or unsubstituted arylthio group” include a group represented by —S(G1), wherein G1 represents the “substituted or unsubstituted aryl group” described in the set of specific examples G1. The number of ring carbon atoms of the “unsubstituted arylthio group” is 6 to 50, preferably 6 to 30, and more preferably 6 to 18, unless otherwise indicated in the description.
In the description herein, specific examples of the “trialkylsilyl group” include a group represented by —Si(G3)(G3)(G3), wherein G3 represents the “substituted or unsubstituted alkyl group” described in the set of specific examples G3. Plural groups represented by G3 in —Si(G3)(G3)(G3) are the same as or different from each other. The number of carbon atoms of each of alkyl groups of the “substituted or unsubstituted trialkylsilyl group” is 1 to 50, preferably 1 to 20, and more preferably 1 to 6, unless otherwise indicated in the description.
In the description herein, specific examples of the “substituted or unsubstituted aralkyl group” include a group represented by -(G3)-(G1), wherein G3 represents the “substituted or unsubstituted alkyl group” described in the set of specific examples G3, and G1 represents the “substituted or unsubstituted aryl group” described in the set of specific examples G1. Accordingly, the “aralkyl group” is a group formed by substituting a hydrogen atom of an “alkyl group” by an “aryl group” as a substituent, and is one embodiment of the “substituted alkyl group”. The “unsubstituted aralkyl group” is an “unsubstituted alkyl group” that is substituted by an “unsubstituted aryl group”, and the number of carbon atoms of the “unsubstituted aralkyl group” is 7 to 50, preferably 7 to 30, and more preferably 7 to 18, unless otherwise indicated in the description.
Specific examples of the “substituted or unsubstituted aralkyl group” include a benzyl group, a 1-phenylethyl group, a 2-phenylethyl group, a 1-phenylisopropyl group, a 2-phenylisopropyl group, a phenyl-t-butyl group, an α-naphthylmethyl group, a 1-α-naphthylethyl group, a 2-α-naphthylethyl group, a 1-α-naphthylisopropyl group, a 2-α-naphthylisopropyl group, a β-naphthylmethyl group, a 1-β-naphthylethyl group, a 2-β-naphthylethyl group, a 1-β-naphthylisopropyl group, and a 2-β-naphthylisopropyl group.
In the description herein, the substituted or unsubstituted aryl group is preferably a phenyl group, a p-biphenyl group, a m-biphenyl group, an o-biphenyl group, a p-terphenyl-4-yl group, a p-terphenyl-3-yl group, a p-terphenyl-2-yl group, a m-terphenyl-4-yl group, a m-terphenyl-3-yl group, a m-terphenyl-2-yl group, an o-terphenyl-4-yl group, an o-terphenyl-3-yl group, an o-terphenyl-2-yl group, a 1-naphthyl group, a 2-naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, a chrysenyl group, a triphenylenyl group, a fluorenyl group, a 9,9′-spirobifluorenyl group, a 9,9-dimethylfluorenyl group, a 9,9-diphenylfluorenyl group, and the like, unless otherwise indicated in the description.
In the description herein, the substituted or unsubstituted heterocyclic group is preferably a pyridyl group, a pyrimidinyl group, a triazinyl group, a quinolyl group, an isoquinolyl group, a quinazolinyl group, a benzimidazolyl group, a phenanthrolinyl group, a carbazolyl group (e.g., a 1-carbazolyl, group, a 2-carbazolyl, group, a 3-carbazolyl, group, a 4-carbazolyl, group, or a 9-carbazolyl, group), a benzocarbazolyl group, an azacarbazolyl group, a diazacarbazolyl group, a dibenzofuranyl group, a naphthobenzofuranly group, an azadibenzofuranyl group, a diazadibenzofuranyl group, a dibenzothiophenyl group, a naphthobenzothiophenyl group, an azadibenzothiophenyl group, a diazadibenzothiophenyl group, a (9-phenyl) carbazolyl group (e.g., a (9-phenyl) carbazol-1-yl group, a (9-phenyl) carbazol-2-yl group, a (9-phenyl) carbazol-3-yl group, or a (9-phenyl) carbazol-4-yl group), a (9-biphenylyl) carbazolyl group, a (9-phenyl)phenylcarbazolyl group, a diphenylcarbazol-9-yl group, a phenylcarbazol-9-yl group, a phenyltriazinyl group, a biphenylyltriazinyl group, a diphenyltriazinyl group, a phenyldibenzofuranyl group, a phenyldibenzothiophenyl group, and the like, unless otherwise indicated in the description.
In the description herein, the carbazolyl group is specifically any one of the following groups unless otherwise indicated in the description.
In the description herein, the (9-phenyl) carbazolyl group is specifically any one of the following groups unless otherwise indicated in the description.
In the general formulae (TEMP-Cz1) to (TEMP-Cz9), * represents a bonding site.
In the description herein, the dibenzofuranyl group and the dibenzothiophenyl group are specifically any one of the following groups unless otherwise indicated in the description.
In the general formulae (TEMP-34) to (TEMP-41), * represents a bonding site.
In the description herein, the substituted or unsubstituted alkyl group is preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a t-butyl group, or the like unless otherwise indicated in the description.
In the description herein, the “substituted or unsubstituted arylene group” is a divalent group derived by removing one hydrogen atom on the aryl ring from the “substituted or unsubstituted aryl group” described above unless otherwise indicated in the description. Specific examples (set of specific examples G12) of the “substituted or unsubstituted arylene group” include divalent groups derived by removing one hydrogen atom on the aryl ring from the “substituted or unsubstituted aryl groups” described in the set of specific examples G1.
In the description herein, the “substituted or unsubstituted divalent heterocyclic group” is a divalent group derived by removing one hydrogen atom on the heterocyclic ring from the “substituted or unsubstituted heterocyclic group” described above unless otherwise indicated in the description. Specific examples (set of specific examples G13) of the “substituted or unsubstituted divalent heterocyclic group” include divalent groups derived by removing one hydrogen atom on the heterocyclic ring from the “substituted or unsubstituted heterocyclic groups” described in the set of specific examples G2.
In the description herein, the “substituted or unsubstituted alkylene group” is a divalent group derived by removing one hydrogen atom on the alkyl chain from the “substituted or unsubstituted alkyl group” described above unless otherwise indicated in the description. Specific examples (set of specific examples G14) of the “substituted or unsubstituted alkylene group” include divalent groups derived by removing one hydrogen atom on the alkyl chain from the “substituted or unsubstituted alkyl groups” described in the set of specific examples G3. In the description herein, the substituted or unsubstituted arylene group is preferably any one of the groups represented by the following general formulae (TEMP-42) to (TEMP-68) unless otherwise indicated in the description.
In the general formulae (TEMP-42) to (TEMP-52). Q1 to Q10 each independently represent a hydrogen atom or a substituent.
In the general formulae (TEMP-42) to (TEMP-52). * represents a bonding site.
In the general formulae (TEMP-53) to (TEMP-62). Q1 to Q10 each independently represent a hydrogen atom or a substituent.
The formulae Q9 and Q10 may be bonded to each other to form a ring via a single bond.
In the general formulae (TEMP-53) to (TEMP-62). * represents a bonding site.
In the general formulae (TEMP-63) to (TEMP-68), Q1 to Q8 each independently represent a hydrogen atom or a substituent.
In the general formulae (TEMP-63) to (TEMP-68), * represents a bonding site.
In the description herein, the substituted or unsubstituted divalent heterocyclic group is preferably the groups represented by the following general formulae (TEMP-69) to (TEMP-102) unless otherwise indicated in the description.
In the general formulae (TEMP-69) to (TEMP-82). Q1 to Q9 each independently represent a hydrogen atom or a substituent.
In the general formulae (TEMP-83) to (TEMP-102), Q1 to Q8 each independently represent a hydrogen atom or a substituent.
The above are the explanation of the “substituents in the description herein”.
In the description herein, the case where “one or more combinations of combinations each including adjacent two or more each are bonded to each other to form a substituted or unsubstituted monocyclic ring, or each are bonded to each other to form a substituted or unsubstituted condensed ring, or each are not bonded to each other” means a case where “one or more combinations of combinations each including adjacent two or more each are bonded to each other to form a substituted or unsubstituted monocyclic ring”, a case where “one or more combinations of combinations each including adjacent two or more each are bonded to each other to form a substituted or unsubstituted condensed ring”, and a case where “one or more combinations of combinations each including adjacent two or more each are not bonded to each other”.
In the description herein, the case where “one or more combinations of combinations each including adjacent two or more each are bonded to each other to form a substituted or unsubstituted monocyclic ring” and the case where “one or more combinations of combinations each including adjacent two or more each are bonded to each other to form a substituted or unsubstituted condensed ring” (which may be hereinafter collectively referred to as a “case forming a ring by bonding”) will be explained below. The cases will be explained for the anthracene compound represented by the following general formula (TEMP-103) having an anthracene core skeleton as an example.
For example, in the case where “one or more combinations of combinations each including adjacent two or more each are bonded to each other to form a ring” among R921 to R930, the combinations each including adjacent two as one combination include 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, and a combination of R929 and R921.
The “one or more combinations” mean that two or more combinations each including adjacent two or more may form rings simultaneously. For example, in the case where R921 and R922 are bonded to each other to form a ring QA, and simultaneously R925 and R926 are bonded to each other to form a ring QB, the anthracene compound represented by the general formula (TEMP-103) is represented by the following general formula (TEMP-104).
The case where the “combination including adjacent two or more forms rings” encompasses not only the case where adjacent two included in the combination are bonded as in the aforementioned example, but also the case where adjacent three or more included in the combination are bonded. For example, this case means that R921 and R922 are bonded to each other to form a ring QA, R922 and R923 are bonded to each other to form a ring QC, and adjacent three (R921, R922, and R923) included in the combination are bonded to each other to form rings, which are condensed to the anthracene core skeleton, and in this case, the anthracene compound represented by the general formula (TEMP-103) is represented by the following general formula (TEMP-105). In the following general formula (TEMP-105), the ring QA and the ring QC share R922.
The formed “monocyclic ring” or “condensed ring” may be a saturated ring or an unsaturated ring in terms of structure of the formed ring itself. In the case where the “one combination including adjacent two” forms a “monocyclic ring” or a “condensed ring”, the “monocyclic ring” or the “condensed ring” may form a saturated ring or an unsaturated ring. For example, the ring QA and the ring QB formed in the general formula (TEMP-104) each are a “monocyclic ring” or a “condensed ring”. The ring QA and the ring QC formed in the general formula (TEMP-105) each are a “condensed ring”. The ring QA and the ring QC in the general formula (TEMP-105) form a condensed ring through condensation of the ring QA and the ring QC. In the case where the ring QA in the general formula (TEMP-104) is a benzene ring, the ring QA is a monocyclic ring. In the case where the ring QA in the general formula (TEMP-104) is a naphthalene ring, the ring QA is a condensed ring.
The “unsaturated ring” means an aromatic hydrocarbon ring or an aromatic heterocyclic ring. The “saturated ring” means an aliphatic hydrocarbon ring or a non-aromatic heterocyclic ring.
Specific examples of the aromatic hydrocarbon ring include the structures formed by terminating the groups exemplified as the specific examples in the set of specific examples G1 with a hydrogen atom.
Specific examples of the aromatic heterocyclic ring include the structures formed by terminating the aromatic heterocyclic groups exemplified as the specific examples in the set of specific examples G2 with a hydrogen atom.
Specific examples of the aliphatic hydrocarbon ring include the structures formed by terminating the groups exemplified as the specific examples in the set of specific examples G6 with a hydrogen atom.
The expression “to form a ring” means that the ring is formed only with the plural atoms of the core structure or with the plural atoms of the core structure and one or more arbitrary element. For example, the ring QA formed by bonding R921 and R922 each other shown in the general formula (TEMP-104) means a ring formed with the carbon atom of the anthracene skeleton bonded to R921, the carbon atom of the anthracene skeleton bonded to R922, and one or more arbitrary element. As a specific example, in the case where the ring QA is formed with R921 and R922, and in the case where a monocyclic unsaturated ring is formed with the carbon atom of the anthracene skeleton bonded to R921, the carbon atom of the anthracene skeleton bonded to R922, and four carbon atoms, the ring formed with R921 and R922 is a benzene ring.
Herein, the “arbitrary element” is preferably at least one kind of an element selected from the group consisting of a carbon element, a nitrogen element, an oxygen element, and a sulfur element, unless otherwise indicated in the description. For the arbitrary element (for example, for a carbon element or a nitrogen element), a bond that does not form a ring may be terminated with a hydrogen atom or the like, and may be substituted by an “arbitrary substituent” described later. In the case where an arbitrary element other than a carbon element is contained, the formed ring is a heterocyclic ring.
The number of the “one or more arbitrary element” constituting the monocyclic ring or the condensed ring is preferably 2 or more and 15 or less, more preferably 3 or more and 12 or less, and further preferably 3 or more and 5 or less, unless otherwise indicated in the description.
What is preferred between the “monocyclic ring” and the “condensed ring” is the “monocyclic ring” unless otherwise indicated in the description.
What is preferred between the “saturated ring” and the “unsaturated ring” is the “unsaturated ring” unless otherwise indicated in the description.
The “monocyclic ring” is preferably a benzene ring unless otherwise indicated in the description.
The “unsaturated ring” is preferably a benzene ring unless otherwise indicated in the description.
In the case where the “one or more combinations of combinations each including adjacent two or more” each are “bonded to each other to form a substituted or unsubstituted monocyclic ring”, or each are “bonded to each other to form a substituted or unsubstituted condensed ring”, it is preferred that the one or more combinations of combinations each including adjacent two or more each are bonded to each other to form a substituted or unsubstituted “unsaturated ring” containing the plural atoms of the core skeleton and 1 or more and 15 or less at least one kind of an element selected from the group consisting of a carbon element, a nitrogen element, an oxygen element, and a sulfur element, unless otherwise indicated in the description.
In the case where the “monocyclic ring” or the “condensed ring” has a substituent, the substituent is, for example, an “arbitrary substituent” described later. In the case where the “monocyclic ring” or the “condensed ring” has a substituent, specific examples of the substituent include the substituents explained in the section “Substituents in Description” described above.
In the case where the “saturated ring” or the “unsaturated ring” has a substituent, the substituent is, for example, an “arbitrary substituent” described later. In the case where the “monocyclic ring” or the “condensed ring” has a substituent, specific examples of the substituent include the substituents explained in the section “Substituents in Description” described above.
The above are the explanation of the case where “one or more combinations of combinations each including adjacent two or more” each are “bonded to each other to form a substituted or unsubstituted monocyclic ring”, and the case where “one or more combinations of combinations each including adjacent two or more” each are “bonded to each other to form a substituted or unsubstituted condensed ring” (i.e., the “case forming a ring by bonding”).
In one embodiment in the description herein, the substituent for the case of “substituted or unsubstituted” (which may be hereinafter referred to as an “arbitrary substituent”) is, for example, a group selected from the group consisting of
In the case where two or more groups each represented by R901 exist, the two or more groups each represented by R901 are the same as or different from each other,
In one embodiment, the substituent for the case of “substituted or unsubstituted” may be a group selected from the group consisting of
In one embodiment, the substituent for the case of “substituted or unsubstituted” may be a group selected from the group consisting of
The specific examples of the groups for the arbitrary substituent described above are the specific examples of the substituent described in the section “Substituents in Description” described above.
In the description herein, the arbitrary adjacent substituents may form a “saturated ring” or an “unsaturated ring”, preferably form a substituted or unsubstituted saturated 5-membered ring, a substituted or unsubstituted saturated 6-membered ring, a substituted or unsubstituted unsaturated 5-membered ring, or a substituted or unsubstituted unsaturated 6-membered ring, and more preferably form a benzene ring, unless otherwise indicated.
In the description herein, the arbitrary substituent may further have a substituent unless otherwise indicated in the description. The definition of the substituent that the arbitrary substituent further has may be the same as the arbitrary substituent.
In the description herein, a numerical range shown by “AA to BB” means a range including the numerical value AA as the former of “AA to BB” as the lower limit value and the numerical value BB as the latter of “AA to BB” as the upper limit value.
Hereinafter, the compound of the present invention will be explained.
The compound of the present invention is represented by the above formula (1), (2) or (3). Hereinafter, the symbols in formulas (1) to (3) and the symbols included in the formulas (1) to (3) described later, will be explained. Unless otherwise specified, the same symbols have the same meaning.
The compound of the present invention represented by the formulas (1) to (3) and the formulas included in the formulas (1) to (3) described later may be referred to as “inventive compound”.
The first compound of the present invention (inventive compound (1)) is represented by the following formula (1).
The phenylene group is o-phenylene group, m-phenylene group, or p-phenylene group, and is preferably p-phenylene group.
The naphthylene group is preferably 1,4-naphthylene group or 2,6-naphthylene group, more preferably 1,4-naphthylene group.
The biphenylene group is preferably 4,4′-biphenylene group or 3,4′-biphenylene group, more preferably 4,4′-biphenylene group.
The substituent is selected from an unsubstituted alkyl group having 1 to 6 carbon atoms or an unsubstituted aryl group having 6 to 12 ring carbon atoms. The unsubstituted alkyl group having 1 to 6 carbon atoms is preferably a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a s-butyl group, or a t-butyl group, more preferably a methyl group, an ethyl group, an isopropyl group, or a t-butyl group, even further preferably a methyl group or a t-butyl group. The unsubstituted aryl group having 6 to 12 ring carbon atoms is preferably phenyl group, biphenyl group, or naphthyl group, more preferably phenyl group or naphthyl group, further preferably phenyl group.
La2 and La3 are each independently a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, or a substituted or unsubstituted biphenylene group, and the substituent is an unsubstituted alkyl group having 1 to 6 carbon atoms or an unsubstituted aryl group having 6 to 12 ring carbon atoms, and no ring is condensed with the phenylene group, the biphenylene group, and the naphthylene group.
The details of the substituted or unsubstituted phenylene group, the substituted or unsubstituted naphthylene group, the substituted or unsubstituted biphenylene group and the substituent are as described for La1.
In one embodiment of the present invention, La2 is a single bond, and in another embodiment, La2 is a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, or a substituted or unsubstituted biphenylene group.
In one embodiment of the present invention, La3 is a single bond, and in another embodiment, La3 is a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, or a substituted or unsubstituted biphenylene group.
In one embodiment of the present invention, one or both of the La2 and the La3 is preferably a single bond.
One selected from Ra1 to Ra5, preferably one selected from Ra1 to Ra3, more preferably Ra1 is a single bond bonded to *10.
Ra1 to Ra5 which are not a single bond bonded to *10 and Ra6 to Ra18 are a hydrogen atom. Provided that two adjacent ones selected from Ra1 to Ra5 which are not a single bond bonded to *10 and Ra6 to Ra18 may be bonded to each other to form a benzene ring, or may not be bonded to each other and therefore may not form a ring.
One selected from Ra21 to Ra24, preferably Ra22, Ra23 or Ra24, more preferably Ra22, is a single bond bonded to *11.
Ra21 to Ra24 which are not single bond bonded to *11 and Ra25 to Ra28 are each independently a hydrogen atom: a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, preferably 1 to 18 carbon atoms, more preferably 1 to 6 carbon atoms; a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, preferably 6 to 25 carbon atoms, more preferably 6 to 12 carbon atoms; or a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, preferably 5 to 24 ring atoms, more preferably 5 to 13 ring atoms.
The unsubstituted alkyl group having 1 to 30 carbon atoms is, for example, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a s-butyl group, a t-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group or a dodecyl group;
The unsubstituted aryl group having 6 to 30 ring carbon atoms is, for example, a phenyl group, a biphenylyl group, a terphenylyl group, a biphenylenyl group, a naphthyl group, an anthryl group, a benzanthryl group, a phenanthryl group, a benzophenanthryl group, a phenalenyl group, a picenyl group, a pentaphenyl group, a pyrenyl group, a chrysenyl group, a benzocrysenyl group, a fluorenyl group, a fluoranthenyl group, a perylenyl group, or a triphenylenyl group;
The substituted aryl group having 6 to 30 ring carbon atoms is preferably, for example, a 9,9-diphenylfluorenyl group, a 9,9-dimethylfluorenyl group, or 9,9-methylphenylfluorenyl group.
The unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms is, for example, a pyrrolyl group, a furyl group, a thienyl group, a pyridyl group, imidazopyridyl group, a pyridazinyl group, a pyrimidinyl group, a pyrazinyl group, triazinyl group, an imidazolyl group, an oxazolyl group, a thiazolyl group, a pyrazolyl group, an isoxazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a triazolyl group, a tetrazolyl group, an indolyl group, an isoindolyl group, an indolizinyl group, a quinolidinyl group, a quinolyl group, an isoquinolyl group, a cinnolyl group, a phthalazinyl group, a quinazolinyl group, a quinoxalinyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, an indazolyl group, a benzisoxazolyl group, a benzisothiazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a phenothiazinyl group, a phenoxazinyl group, a xanthenyl group, a benzofuranyl group, an isobenzofuranyl group, a naphthobenzofuranyl group, a dibenzofuranyl group, a benzothiophenyl group (benzothienyl group, same applies hereinafter), an isobenzothiophenyl group (isobenzothienyl group, same applies hereinafter), a naphthobenzothiophenyl group (naphthobenzothienyl group, same applies hereinafter), a dibenzothiophenyl group (dibenzothienyl group, same applies hereinafter), or a carbazolyl group;
preferably, a benzofuranyl group, an isobenzofuranyl group, a naphthobenzofuranyl group, a dibenzofuranyl group, a benzothiophenyl group, an isobenzothiophenyl group, a naphthobenzothiophenyl group, a dibenzothiophenyl group, a carbazolyl group (9-carbazolyl group, or 1-, 2-, 3-, or 4-carbazolyl group).
Two adjacent ones selected from Ra21 to Ra24 which are not a single bond bonded to *11 and Ra25 to Ra28 (Ra21 and Ra22, Ra22 and Ra23, Ra23 and Ra24, Ra25 and Ra26, Ra26 and Ra27, Ra27 and Ra28) may be bonded to each other to form a benzene ring, or may not be bonded to each other and therefore may not form a ring.
All of Ra21 to Ra24 and Ra25 to Ra28 which are not a single bond bonded to *11, may be a hydrogen atom.
RA and RB are each independently a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms. Provided that RA and RB may be bonded to each other to form a substituted or unsubstituted spiro ring with the carbon atom at the 9-position of the fluorene skeleton, or may not be bonded to each other and may not form a spiro ring.
The details of the substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, or the substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or the substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms are each described for Ra21 to Ra24 which are not a single bond bonded to *11 and Ra25 to Ra28.
In one embodiment of the present invention, at least one of RA and RB is preferably a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms.
In one embodiment of the present invention, RA and RB are each independently preferably a methyl group or a phenyl group.
In another embodiment of the present invention, RA and RB preferably form a substituted or unsubstituted spiro ring.
The spiro ring is a hydrocarbon ring or a heterocyclic ring, and selected from monocyclic, bridged bicyclo ring, and bridged tricyclo ring. Examples of substituted or unsubstituted spiro rings are shown below; but are not limited thereto. * represents the bonding position of the fluorene skeleton to the benzene ring.
Ara1 is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms, or a triarylsilyl group having a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms. The substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or the substituted or unsubstituted aromatic heterocyclic group having 5 to 30 ring atoms are each described for Ra21 to Ra24 which are not a single bond bonded to *11 and Ra25 to Ra28. The details of the substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms in the triarylsilyl group are as described for Ra21 to Ra24 and Ra25 to Ra28, which are not a single bond bonded to *11. The triarylsilyl group is preferably a triphenylsilyl group.
In one embodiment of the present invention, Ara1 is preferably represented by the following (1a), (1c), (1d), (1e), or (1f), more preferably represented by (1a), (1c), or (1e).
In the formula (1a),
The unsubstituted alkyl group having 1 to 6 carbon atoms is preferably a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a s-butyl group, or a t-butyl group, more preferably a methyl group, an ethyl group, isopropyl group, or t-butyl group, further preferably a methyl group or a t-butyl group.
The unsubstituted aryl group having 6 to 12 ring carbon atoms is preferably a phenyl group, a biphenyl group, or a naphthyl group, more preferably a phenyl group or a naphthyl group, and further preferably a phenyl group.
The biphenyl group includes an o-biphenyl group, a m-biphenyl group, and a p-biphenyl group, is preferably a m-biphenyl group and a p-biphenyl group, more preferably a p-biphenyl group.
The naphthyl group includes a 1-naphthyl group and a 2-naphthyl group, is preferably 1-naphthyl group.
All of R1 to R5 which are not a single bond bonded to *f of the formula (1a), and R11 to R15 may be a hydrogen atom.
In the formula (1c),
The details of the unsubstituted alkyl group having 1 to 6 carbon atoms and the aryl group having 6 to 12 ring carbon atoms are the same as the corresponding groups described for formula (1a).
In one embodiment of the present invention, R21 is a single bond bonded to *a, in another embodiment, R22 is a single bond bonded to *a.
All of R21 to R28 which are not a single bond bonded to *a may be a hydrogen atom.
In the formula (1d),
The details of the unsubstituted alkyl group having 1 to 6 carbon atoms and the unsubstituted aryl group having 6 to 12 ring carbon atoms are the same as the corresponding groups described for formula (1a).
It is preferable that one selected from R37, R38 and R39 is a single bond bonded to *b. In one embodiment of the present invention, R37 is a single bond bonded to *b, in another embodiment R38 is a single bond bonded to *b, and in still another embodiment R39 is a single bond bonded to *b.
All of R31 to R40 which are not a single bond bonded to *b may be a hydrogen atom.
In the formula (1e),
In one embodiment of the present invention, the formula (1e) is represented by any of the following formulas.
The details of the unsubstituted alkyl group having 1 to 6 carbon atoms and the unsubstituted aryl group having 6 to 12 ring carbon atoms are the same as the corresponding groups described for formula (1a).
The unsubstituted aromatic heterocyclic group having 5 to 13 ring atoms is preferably a pyrrolyl group, a furyl group, a thienyl group, a pyridyl group, a pyrimidinyl group, a triazinyl group, a quinolyl group, an isoquinolyl group, a quinazolinyl group, a benzimidazolyl group, a benzofuranyl group, a benzothiophenyl group (a benzothienyl group), a carbazolyl group, a dibenzofuranyl group, or a dibenzothiophenyl group (a dibenzothienyl group).
Ra is preferably an unsubstituted phenyl group or an unsubstituted naphthyl group (1-naphthyl group or 2-naphthyl group).
It is preferable that both of Rb and Rc are a methyl group or a phenyl group, or that Rb is a phenyl group and Rc is a methyl group.
The details of the spiro ring formed by bonding Rb and Rc to each other are as described for the spiro ring formed by bonding RA and RB to each other in formula (1).
When X is an oxygen atom or a sulfur atom, one selected from R45 to R48 is preferably a single bond bonded to *c.
When X is NRa, one selected from R45 to R48 is preferably a single bond bonded to *c.
When X is CRbRc, one selected from R45 to R48 is preferably a single bond bonded to *c.
All of R41 to R48 which are not a single bond bonded to *c may be a hydrogen atom.
In the formula (1f),
The details of the unsubstituted alkyl group having 1 to 6 carbon atoms are as described for formula (1a).
In one embodiment of the present invention, two adjacent ones selected from R61 to R65, that is, one or plural adjacent two selected from R61 and R62, R62 and R63, R63 and R64, and R64 and R65, are bonded to each other to form one or plural substituted or unsubstituted benzene rings. In another embodiment of the present invention, two adjacent ones selected from R61 to R65 are not bonded to each other and therefore do not form a ring structure.
In one embodiment of the present invention, two adjacent ones selected from R71 to R75, that is, one or plural adjacent two selected from R71 and R72, R72 and R73, R73 and R74, and R74 and R75, are bonded to each other to form one or more substituted or unsubstituted benzene rings. In another embodiment of the present invention, two adjacent ones selected from R71 to R75 are not bonded to each other and therefore do not form a ring structure.
All of R51 to R55 which are neither a single bond bonded to *d nor a single bond bonded to *e may be a hydrogen atom, all of R61 to R65 may be a hydrogen atom, or all of R71 to R75 may be a hydrogen atom.
The formula (1f) includes groups represented by the following formulas (1fa) to (1fe), and (1fa), (1fb) or (1fd) are preferred.
The second compound of the present invention (inventive compound (2)) is represented by the following formula (2).
Ara2 is a condensed aryl group having 14 to 30 ring carbon atoms substituted with an unsubstituted alkyl group having 1 to 30 carbon atoms or unsubstituted, a substituted or unsubstituted condensed aromatic heterocyclic group having 13 to 30 ring atoms, or a substituted or unsubstituted fluorenyl group.
The unsubstituted alkyl group having 1 to 30 carbon atoms, preferably 1 to 18 carbon atoms, and more preferably 1 to 6 carbon atoms is as described for Ra21 to Ra24 which are not a single bond bonded to *11 of the formula (1), and Ra25 to Ra28.
The unsubstituted condensed aryl group having 14 to 30 ring carbon atoms is selected from, for example, a phenanthryl group, an anthryl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a picenyl group, and a perylenyl group. A phenanthryl group is preferred.
The unsubstituted condensed aromatic heterocyclic group having 13 to 30 ring atoms is selected from, for example, a dibenzofuranyl group, a dibenzothiophenyl group, a carbazolyl group, a phenanthridinyl group, and a phenanthrolinyl group, and a dibenzofuranyl group, a dibenzothiophenyl group, and a carbazolyl group are preferred.
The substituted fluorenyl group is preferably a 9,9-diphenylfluorenyl group, a 9,9-dimethylfluorenyl group, a 9,9-methylphenylfluorenyl group, or a spirofluorenyl group. The details of the spirofluorenyl group are as described for RA and RB in formula (1).
In one embodiment of the present invention, Ara2 is preferably represented by any one of the following formulas (11) to (13).
In the formula (11),
The details of the unsubstituted alkyl group having 1 to 30 carbon atoms are as described for Ra21 to Ra24 which are not a single bond bonded to *11 of the formula (1), and Ra25 to Ra28.
It is preferable that one selected from R137, R138 and R139 is a single bond bonded to *b. In one embodiment of the present invention, R137 is a single bond bonded to *1b, in another embodiment R138 is a single bond bonded to *b, and in still another embodiment R139 is a single bond bonded to *1b.
All of R131 to R140 which are not a single bond bonded to *1b may be a hydrogen atom.
In the formula (12),
The details of the unsubstituted alkyl group having 1 to 30 carbon atoms are as described for Ra21 to Ra24 which are not a single bond bonded to *11 of the formula (1), and Ra25 to Ra28.
When X1 is an oxygen atom or a sulfur atom, one selected from R145 to R148 is preferably a single bond bonded to *1c. In one embodiment of the present invention, R145, in another embodiment R146, in another embodiment R147, in another embodiment R148, is preferably a single bond bonded to *1c.
When X1 is NRa, one selected from R145 to R148 is preferably a single bond bonded to *1c. In one embodiment of the present invention, R145, in another embodiment R146, in another embodiment R147, in another embodiment R148, is preferably a single bond bonded to *1c.
All of R141 to R148 which are not a single bond bonded to * 1c may be a hydrogen atom.
In the formula (13),
The details of the substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, the substituted or unsubstituted aryl group having 6 to 12 ring carbon atoms, and the substituted or unsubstituted aromatic heterocyclic group having 5 to 13 ring atoms are as described above.
It is preferable that both of Rm and Rn are a methyl group or a phenyl group, or that Rm is a phenyl group and Rn is a methyl group.
The details of the substituted or unsubstituted spiro ring formed by bonding Rm and Rn to each other are as described for the spiro ring formed by bonding RA and RB to each other in formula (1).
Preferably one selected from R245 to R248, more preferably R246 is a single bond bonded to *2c.
All of R241 to R248 which are not a single bond bonded to *2c may be a hydrogen atom.
The third compound of the present invention (inventive compound (3)) is represented by the following formula (3).
One selected from Ra31 to Ra48 is a single bond bonded to *12, and Ra31 to Ra48 which are not a single bond bonded to *12 are a hydrogen atom. Preferably Ra31, Ra32, Ra33, Ra37, or Ra39, more preferably Ra31, Ra37, or Ra39 is a single bond bonded to *12.
Two adjacent ones selected from Ra31 to Ra48 which are not a single bond bonded to *12 may be bonded to each other to form a benzene ring, or may not be bonded to each other and therefore may not form a ring.
RC and RD are bonded to each other to form a substituted or unsubstituted spiro ring with the carbon atom at the 9-position of the fluorene skeleton. The details of the substituted or unsubstituted spiro ring are as described for the spiro ring formed by bonding RA and RB to each other in formula (1).
Ara3 is a phenyl group or a naphthyl group which may be substituted with a triarylsilyl group having a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, and an unsubstituted phenyl group or an unsubstituted naphthyl group are preferred.
The details of the substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms in the triarylsilyl group are as described for Ra21 to Ra24 which are not a single bond bonded to *11, and Ra25 to Ra28. The triarylsilyl group is preferably a triphenylsilyl group.
As mentioned above, “hydrogen atom” used in this description includes light hydrogen atoms, deuterium atoms, and tritium atoms. Accordingly, the inventive compounds may include naturally occurring deuterium atoms.
Further, a deuterium atom may be intentionally introduced into the inventive compound A by using a deuterated compound for a part of or all of the raw material compounds. Therefore, in one embodiment of the present invention, the inventive compounds contain at least one deuterium atom. That is, the inventive compound is a compound represented by any one of formulas (1) to (3), and may be a compound in which at least one of the hydrogen atoms contained in the compound is a deuterium atom.
At least one hydrogen atom selected from the following hydrogen atoms may be a deuterium atom. In addition, in the following, “substituted or unsubstituted”, the number of carbon atoms, and the number of atoms are omitted.
When Ara3 in the formula (3) is a phenyl group or a naphthyl group substituted with a triarylsilyl group having a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, hydrogen atoms contained in the aryl group.
The deuteration rate of the inventive compound depends on the deuteration rate of the raw material compounds used. Even when a raw material with a predetermined deuteration rate is used, a certain proportion of naturally occurring light hydrogen isotopes may be included. Therefore, the embodiment of the deuteration rate of the inventive compound represented below includes a ratio which takes into account trace amounts of naturally occurring isotopes, with respect to the ratio obtained by simply counting the number of deuterium atoms represented by the chemical formula.
The deuteration rate of the inventive compound is preferably 1% or more, more preferably 3% or more, further preferably 5% or more, further more preferably 10% or more, further more preferably 50% or more.
The inventive compound may be a mixture containing a deuterated compound and a non-deuterated compound, or a mixture of two or more compounds having different deuteration rate. The deuteration rate of these mixtures is preferably 1% or more, more preferably 3% or more, further preferably 5% or more, further more preferably 10% or more, further more preferably 50% or more, and less than 100%.
Further, the ratio of the number of deuterium atoms with respect to the total number of hydrogen atoms in the inventive compound is preferably 1% or more, more preferably 3% or more, further preferably 5% or more, further more preferably 10% or more, and 100% or less.
When the “substituted or unsubstituted XX group” included in the definitions of the above formulas is a substituted XX group, the details of the substituent are as described in “substituents in the case of “substituted or unsubstituted””, and is preferably an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 ring atoms, or an aromatic heterocyclic group having 5 to 13 ring atoms, more preferably an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 ring carbon atoms. The details of each group are as described above.
The inventive compounds can be easily produced by those skilled in the art with reference to the following synthesis examples and known synthesis methods.
Specific examples of the inventive compounds are shown below, but the compounds are not limited to the following exemplified compounds.
In the following specific examples, D represents a deuterium atom.
The material for organic EL device of the present invention contains an inventive compound. The content of the inventive compound in the material for organic EL device is 1 mass % or more (including 100%), preferably 10 mass % or more (including 100%), more preferably 50 mass % or more (including 100%), further preferably 80 mass % or more (including 100%), particularly preferably 90 mass % or more (including 100%). The material for organic EL device of the present invention is useful for manufacturing an organic EL device.
An organic EL device which is one embodiment of the present invention contains an anode, a cathode, and an organic layer placed between the anode and the cathode. The organic layer contains a light emitting layer, and at least one layer of the organic layer contains an inventive compound.
Examples of the organic layer containing the inventive compound include a hole transporting band (hole injecting layer, hole transporting layer, electron blocking layer, exciton blocking layer, etc.) provided between the anode and the light emitting layer, the light emitting layer, a space layer, an electron transport zone (electron injecting layer, electron transporting layer, hole blocking layer, etc.) provided between the cathode and the light emitting layer, however it is not limited thereto. The inventive compound is preferably used as a material for a hole transporting band or a light emitting layer of a fluorescent or phosphorescent EL device, more preferably used as a material for a hole transport zone, and further more preferably used as a material for a hole injecting layer, a hole transporting layer, an electron blocking layer, or an exciton blocking layer, particularly preferably used as a material for a hole injecting layer or a hole transporting layer.
The organic EL device of the present invention may be a monochromatic fluorescent or phosphorescent type light emitting element, or a fluorescent/phosphorescent hybrid type white light emitting element, and may be a simple type having a single light emitting unit, or a tandem type having plural light emitting units, and it is preferably a fluorescent type light emitting element. Here, the “light emitting unit” refers to a minimum unit which contains an organic layer, in which at least one of the layers is a light emitting layer, and emits light by recombining injected holes and electrons.
For example, examples of the typical element configuration of a simple type organic EL device include the following element configurations.
Further, the light emitting unit may be a multilayer type having plural phosphorescent light emitting layers or fluorescent light emitting layers, and in that case, a space layer may be contained between each light emitting layer, for the purpose of preventing excitons which are generated in the phosphorescent light emitting layer from diffusing into the fluorescent light emitting layer. A typical layer configuration of a simple type light emitting unit is shown below: Layers in parentheses are optional.
Each of the phosphorescent or fluorescent light emitting layers may respectively show different light emitting colors. Specifically, in the light emitting unit (f), examples include a layer configuration of (Hole injecting layer/) Hole transporting layer/First phosphorescent light emitting layer (red light emitting)/Second phosphorescent light emitting layer (green light emitting)/Space layer/Fluorescent light emitting layer (blue light emitting)/Electron transporting layer, etc.
Note that an electron blocking layer may be provided between each light emitting layer and the hole transporting layer or space layer, as appropriate. Further, a hole blocking layer may be provided between each light emitting layer and the electron transporting layer as appropriate. By providing an electron blocking layer or a hole blocking layer, it is possible to confine electrons or holes within the light emitting layer, increase the probability of charge recombination in the light emitting layer, and improve a light emission efficiency.
Examples of the typical device configuration of tandem type organic EL device include the following element configurations.
Here, for example, as the first light emitting unit and the second light emitting unit, each independently can be selected from the above light emitting units.
The intermediate layer is generally also referred to as an intermediate electrode, intermediate conductive layer, charge generation layer, electron extraction layer, connection layer, or intermediate insulating layer, and any known material configuration in which electrons are provided to the first light emitting unit and holes are provided to the second light emitting unit, can be used.
In the present invention, a host combined with a fluorescent dopant material (fluorescent material) is referred to as a fluorescent host, and a host combined with a phosphorescent dopant material is referred to as a phosphorescent host. Fluorescent hosts and phosphorescent hosts are not distinguished only by molecular structure. That is, the phosphorescent host means a material forming a phosphorescent light emitting layer containing a phosphorescent dopant, and does not mean that it cannot be used as a material to form a fluorescent light emitting layer. The same applies to fluorescent hosts.
The substrate is used as a support for the organic EL device. As the substrate, for example, a plate of glass, quartz, and plastic can be used. Further, a flexible substrate may be used. Examples of the flexible substrate include plastic substrates made of polycarbonate, polyarylate, polyethersulfone, polypropylene, polyester, polyvinyl fluoride, and polyvinyl chloride. Moreover, an inorganic vapor-deposited film can also be used.
For the anode formed on the substrate, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a large work function (specifically, 4.0 eV or more). Specifically, for example, examples include indium oxide-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, examples include gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti), or nitrides of the above metals (for example, titanium nitride).
These materials are usually film-formed by sputtering method. For example, the indium oxide-zinc oxide can be formed by using a target in which 1 to 10 wt % of zinc oxide is added to indium oxide, and the indium oxide containing tungsten oxide and zinc oxide can be formed by using a target in which 0.5 to 5 wt % of tungsten oxide and 0.1 to 1 wt % of zinc oxide are contained into indium oxide, with a sputtering method. In addition, it may be produced by a vacuum deposition method, a coating method, an inkjet method, a spin coating method, or the like.
As mentioned above, the organic layer may contain a hole transporting band between the anode and the light emitting layer. The hole transporting band is composed of a hole injecting layer, a hole transporting layer, an electron blocking layer, and the like. The Hole transporting band preferably contains the inventive compound. At least one of these layers constituting the hole transporting layer preferably contains the inventive compound, and particularly the inventive compound is more preferably contained in the hole transporting layer.
Since the hole injecting layer formed in contact with the anode is formed using a material which facilitate hole injection regardless of the work function of the anode, materials commonly used as electrode materials (for example, metals, alloys, electrically conductive compounds, mixtures thereof, elements belonging to Group 1 or Group 2 of the periodic table of elements) can be used.
Elements belonging to Group 1 or Group 2 of the Periodic Table of Elements, which are materials with a small work function, that is, alkali metals such as lithium (Li) and cesium (Cs), and alkaline earth metals such as magnesium (Mg), calcium (Ca), and strontium (Sr), alloys containing these (for example, MgAg, AlLi), rare earth metals such as europium (Eu), ytterbium (Yb), alloys containing these, can also be used. In addition, when forming an anode using an alkali metal, an alkaline earth metal, or an alloy containing these, a vacuum deposition method or a sputtering method can be used. Furthermore, when silver paste or the like is used, a coating method, an inkjet method, or the like can be used.
The hole injecting layer is a layer containing a material having high hole injection properties (hole injecting material), and is formed between the anode and the light emitting layer, or, between the hole transporting layer and the anode when present.
As the hole injecting materials other than the inventive compound, molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, manganese oxide, etc. can be used.
Examples of the hole injecting materials contain aromatic amine compounds such as 4,4′,4″-tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4′-bis(N-{4-[N′-(3-methylphenyl)-N′-phenylamino]phenyl}-N-phenylamino) biphenyl (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), which are low molecular weight organic compounds.
High molecular weight compounds (oligomers, dendrimers, polymers, etc.) can also be used. For example, examples include high molecular weight compounds such as 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), poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine] (abbreviation: Poly-TPD). In addition, high molecular weight compounds to which an acid is added, such as poly(3,4-ethylenedioxy thiophene)/poly(styrene sulfonic acid) (PEDOT/PSS) or polyaniline/poly(styrene sulfonic acid) (PAni/PSS), can also be used.
Furthermore, it is also preferable to use acceptor materials such as a hexaazatriphenylene (HAT) compound represented by the following formula (K).
(In the above formula, R221 to R226 each independently represent a cyano group, —CONH2, a carboxy group, or —COOR227 (R227 represents an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 20 carbon atoms). Furthermore, two adjacent groups selected from R221 and R222, R223 and R224, and R225 and R226 may be bonded to each other to form a group represented by —CO—O—CO—).
Examples of R227 include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a t-butyl group, a cyclopentyl group, and a cyclohexyl group.
The hole transporting layer is a layer containing a material having high hole transport properties (hole transporting material), and is formed between the anode and the light emitting layer, or, between the hole injecting layer and the light emitting layer when present. The inventive compounds may be used alone or in combination with the compounds listed below in the hole transporting layer.
The hole transporting layer may have a single-layer structure or a multilayer structure including two or more layers. For example, the hole transporting layer may have a two-layer structure including a first hole transporting layer (on the anode side) and a second hole transporting layer (on the cathode side). That is, the hole transporting band may include the first hole transporting layer on the anode side and the second hole transporting layer on the cathode side. Further, the hole transporting layer may have a three-layer structure containing, in order from the anode side, a first hole transporting layer, a second hole transporting layer, and a third hole transporting layer. That is, the third hole transporting layer may be placed between the second hole transporting layer and the light emitting layer.
In one embodiment of the present invention, the hole transporting layer having the single-layer structure is preferably adjacent to the light emitting layer, and the hole transporting layer closest to the cathode in the multilayer structure which is, for example, the second hole transporting layer in the two-layer structure and the third hole transporting layer in the three-layer structure are preferably adjacent to the light emitting layer. In another embodiment of the present invention, an electron blocking layer, which will be described later, may be interposed between the hole transporting layer and the light emitting layer in the single-layer structure, or between the hole transporting layer closest to the light emitting layer and the light emitting layer in the multilayer structure.
When the hole transporting layer has a two-layer structure, at least one of the first hole transporting layer and the second hole transporting layer contains the inventive compound. That is, the inventive compound is contained only in the first hole transporting layer, only in the second hole transporting layer, or in both the first hole transporting layer and the second hole transporting layer.
In one embodiment of the present invention, the inventive compound is preferably included in the second hole transporting layer. That is, it is preferable that the inventive compound is contained only in the second hole transporting layer, or that the inventive compound is contained in the first hole transporting layer and the second hole transporting layer.
When the hole transporting layer has a three-layer structure, at least one of the first to third hole transporting layers contains the inventive compound. That is, the inventive compound is contained in only one layer selected from the first to third hole transporting layers (only the first hole transporting layer, only the second hole transporting layer, or only the third hole transporting layer), in only two layers selected from the first to third hole transporting layers (only the first hole transporting layer and the second hole transporting layer, only the first hole transporting layer and the third hole transporting layer, or only the second hole transporting layer), or in all of the first to third hole transporting layers.
In one embodiment of the present invention, the inventive compound is preferably included in the third hole transporting layer. That is, it is preferable that the inventive compound is contained only in the third hole transporting layer, or that the inventive compound is preferably contained in the third hole transporting layer and one or both of the first hole transporting layer and the second hole transporting layer.
In one embodiment of the present invention, the inventive compound contained in each of the hole transporting layers is preferably a light hydrogen body from the viewpoint of manufacturing cost. The light hydrogen body refers to an inventive compound in which all hydrogen atoms are light hydrogen atoms.
Therefore, the present invention includes an organic EL device in which one or both of the first hole transporting layer and the second hole transporting layer (in the case of a two-layer structure), or at least one of the first to third hole transporting layers contain an inventive compound which substantially contains only a light hydrogen body. The “inventive compound which substantially contains only a light hydrogen body” means that the content ratio of the light hydrogen body with respect to the total amount of inventive compound is 90 mol % or more, preferably 95 mol % or more, more preferably 99 mol % or more (including 100% for each).
As the hole transporting layer material other than the inventive compound, for example, aromatic amine compounds, carbazole derivatives, anthracene derivatives can be used.
Examples of aromatic amine compounds 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-phenylfluoren-9-yl)triphenylamine (abbreviation: BAFLP), 4,4′-bis[N-(9,9-dimethylfluoren-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′-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB). The above compounds have a hole mobility of 10−6 cm2/Vs or more.
Examples of carbazole derivatives include 4,4′-di(9-carbazolyl) biphenyl (abbreviation: CBP), 9-[4-(9-carbazolyl)phenyl]-10-phenylanthracene (abbreviation: CzPA), and 9-phenyl-3-[4-(10)-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA).
Examples of anthracene derivatives include 2-t-butyl-9,10-di(2-naphthyl) anthracene (abbreviation: t-BuDNA), 9,10-di(2-naphthyl) anthracene (abbreviation: DNA), and 9,10-diphenylanthracene (abbreviation: DPAnth).
High molecular weight compound such as poly(N-vinylcarbazole) (abbreviation: PVK) and poly(4-vinyltriphenylamine) (abbreviation: PVTPA) can also be used.
Provided that compounds other than those mentioned above may be used as long as they have higher hole transport properties than electron transport properties.
In the organic EL device having a hole transporting layer having a two-layer structure according to the present invention, the first hole transporting layer preferably contains one or plural of the compounds represented by the following formula (11) or formula (12).
In the organic EL device having a hole transporting layer having three-layer structure according to the present invention, one or both of the first hole transporting layer and the second hole transporting layer preferably contains one or plurality of the compounds represented by the following formula (11) or formula (12).
In the organic EL device of the present invention having a hole transporting layer with an n-layer structure (n is an integer of 4 or more), at least one of the first to the (n−1)th hole transporting layers preferably contains one or plural compounds represented by (11) or formula (12).
[In the formula (11) and (12),
In formulas (11) and (12), A1, B1, C1, A2, B2, C2, and D2 are preferably each independently selected from a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted carbazolyl group group.
Further, more preferably, in formula (11), at least one of A1, B1, and C1, and in formula (12), at least one of A2, B2, C2, and D2 is a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted fluorenyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothiophenyl group, and a substituted or unsubstituted carbazolyl group.
The fluorenyl groups which can be as A1, B1, C1, A2, B2, C2, and D2 may have a substituent at the 9-position, for example, 9,9-dimethylfluorenyl group, and 9,9-diphenylfluorenyl group. Further, the substituents at the 9-position may form a ring with each other, for example, the substituents at the 9-position may form a fluorene skeleton or a xanthene skeleton, with each other.
LA1, LB1, LC1, LA2, LB2, LC2 and LD2 are preferably each independently a single bond or a substituted or unsubstituted arylene group having 6 to 12 ring carbon atoms.
Specific examples of the compound represented by the formulas (11) and (12) include the following compounds.
The light emitting layer is a layer containing a material (dopant material) having a high light emitting properties, and various materials can be used. For example, a fluorescent material or a phosphorescent material can be used as a dopant material. The fluorescent material is a compound which emits light from a singlet excited state, and the phosphorescent material is a compound which emits light from a triplet excited state.
In one embodiment of the organic EL device according to the present invention, the light emitting layer is a single layer.
Further, in one embodiment of the organic EL device according to the present invention, the light emitting layer includes a first light emitting layer and a second light emitting layer.
As a blue fluorescent material which can be used in the light emitting layer, pyrene derivatives, styrylamine derivatives, chrysene derivatives, fluoranthene derivatives, fluorene derivatives, diamine derivatives, triarylamine derivatives, etc. can be used. Specifically, the examples include N,N′-bis[4-(9H-carbazol-9-yl)phenyl]-N,N′-diphaenylstilbene-4,4′-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4′-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), and 4-(10-phenyl-9-anthryl)-4′-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA).
As a green fluorescent material which can be used in the light emitting layer, aromatic amine derivatives, etc. can be used. Specifically, the examples include N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N′,N′-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthryl]-N,N′,N′-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), N-[9,10-bis(1,1′-biphenyl-2-yl)]-N-[4-(9H-carbazole)-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), and N,N,9-triphenylanthracen-9-amine (abbreviation: DPhAPhA).
As a red fluorescent material which can be used in the light emitting layer, tetracene derivatives, diamine derivatives, etc. can be used. Specifically, the examples include N,N,N′,N′-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), and 7,14-diphenyl-N,N,N,N′-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviation: p-mPhAFD).
In one embodiment of the present invention, it is preferable that the light emitting layer contains a fluorescent material (fluorescent dopant material).
As a blue phosphorescent material which can be used in the light emitting layer, metal complexes such as an iridium complex, an osmium complex, a platinum complexes are used. Specifically, the examples include bis[2-(4′,6′-difluorophenyl)pyridinato-N,C2′]iridium(III)tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4′,6′-difluoro phenyl)pyridinato-N,C2′]iridium(III)picolinate (abbreviation: FIrpic), bis[2-(3′,5′bistrifluoromethylphenyl)pyridinato-N,C2′]iridium(III)picolinate (abbreviation: Ir(CF3ppy)2(pic)), and bis[2-(4′,6′-difluorophenyl)pyridinato-N,C2′]iridium(III)acetylacetonate (abbreviation: FIracac).
As a green phosphorescent material which can be used in the light emitting layer, iridium complexes and the like are used. The examples include tris(2-phenylpyridinato-N,C2′)iridium(III) (abbreviation: Ir(ppy)3), bis(2-phenylpyridinato-N,C2′)iridium(III)acetylacetonate (abbreviation: Ir(ppy)2(acac)), bis(1,2-diphenyl-1H-benzimidazolato)iridium(III)acetylacetonate (abbreviation: Ir(pbi)2(acac)), and bis(benzo[h]quinolinato)iridium(III)acetylacetonate (abbreviation: Ir(bzq)2(acac)).
As a red phosphorescent material which can be used in the light emitting layer, metal complexes such as an iridium complex, a platinum complex, a terbium complex, and an europium complex are used. Specifically; the examples include organic metal complexes such as bis[2-(2′-benzo[4,5-a]thienyl)pyridinato-N,C3′]iridium(III)acetylacetonate (abbreviation: Ir(btp)2(acac)), bis(1-phenylisoquinolinato-N,C2′)iridium(III)acetylacetonate (abbreviation: Ir(piq)2(acac)), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: Ir(Fdpq)2(acac)), and 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP).
Further, rare earth metal complexes such as tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: Tb(acac)3(Phen)), tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: Eu(DBM)3(Phen)), and tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: Eu(TTA)3(Phen)) can be used as the phosphorescent material since they emit light from rare earth metal ions (electronic transition between different multiplicities).
The light emitting layer may have a configuration in which the above-described dopant material is dispersed in another material (host material). It is preferable to use a material which has a higher lowest unoccupied orbital level (LUMO level) and a lower highest occupied orbital level (HOMO level) than the dopant material.
As the host material, for example,
For example, metal complexes such as tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Almq3), bis(10)-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ);
condensed aromatic compounds such as 9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: CzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: DPCzPA), 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 9,9′-bianthryl (abbreviation: BANT), 9,9′-(stilbene-3,3′-diyl)diphenanthrene (abbreviation: DPNS), 9,9′-(stilbene-4,4′-diyl)diphenanthrene (abbreviation: DPNS2), 3,3′,3″-(benzene-1,3,5-triyl)tripyrene (abbreviation: TPB3), 9,10-diphenylanthracene (abbreviation: DPAnth), and 6,12-dimethoxy-5,11-diphenylchrysene; and aromatic amine compounds such as N,N-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: CzAIPA), 4-(10)-phenyl-9)-anthryl)triphenylamine (abbreviation: DPhPA), N,9-diphenyl-N-[4-(10)-phenyl-9)-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl]phenyl}-9H-carbazol-3-amine (abbreviation: PCAPBA), N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (abbreviation: TPD), 4,4′-bis[N-(9,9-dimethylfluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: DFLDPBi), and 4,4′-bis[N-(spiro-9,9′-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB): can be used. Multiple types of host materials may be used.
In particular, in the case of a blue fluorescent element, it is preferable to use the following anthracene compound as the host material.
In one embodiment of the organic EL device according to the present invention, when the light emitting layer contains a first light emitting layer and a second light emitting layer, at least one of the components constituting the first light emitting layer is different from the components constituting the second light emitting layer. For example, the examples include an embodiment in which the dopant material contained in the first light emitting layer is different from the dopant material contained in the second light emitting layer, and an embodiment in which the host material contained in the first light emitting layer is different from the host material contained in the second light emitting layer.
In the organic EL device of the present invention, the light emitting layer may contain a light emitting compound (hereinafter sometimes simply referred to as a “fluorescent compound”) which emits fluorescent light with a main peak wavelength of 500 nm or less.
The method for measuring the main peak wavelength of a compound is as follows. A 5 μmol/L toluene solution of the compound to be measured is prepared and placed in a quartz cell, and the emission spectrum of this sample (vertical axis: emission intensity, horizontal axis: wavelength) is measured at room temperature (300K). The emission spectrum can be measured using a spectrofluorometer (device name: F-7000) manufactured by Hitachi High-Tech Science Co., Ltd. Note that the emission spectrum measuring device is not limited to the device used here.
In the emission spectrum, the peak wavelength of the emission spectrum at which the emission intensity is maximum is defined as the main peak wavelength. Note that in this specification, the main peak wavelength may be referred to as fluorescence main peak wavelength (FL-peak).
The fluorescent compound may be the dopant material or the host material.
When the light emitting layer is a single layer, only one of the dopant material and the host material may be the fluorescent compound, or both may be the fluorescent compound.
Further, when the light emitting layer contains a first light emitting layer (on the anode side) and a second light emitting layer (on the cathode side), only one of the first light emitting layer and the second light emitting layer contains the fluorescent compound, or both of the light emitting layers may contain the fluorescent compound. When the first light emitting layer contains the fluorescent compound, only one of the dopant material and the host material contained in the first light emitting layer may be the fluorescent compound, or both may be the fluorescent compound. Further, when the second light emitting layer contains the fluorescent compound, only one of the dopant material and the host material contained in the second light emitting layer may be the fluorescent compound, or both may be the fluorescent compound.
The electron transporting layer is a layer containing a material having high electron transport properties (electron transporting material), and is formed between the light emitting layer and the cathode, or, between the electron injecting layer and the light emitting layer when present.
The electron transporting layer may have a single-layer structure or a multilayer structure including two or more layers. For example, the electron transporting layer may have a two-layer structure including a first electron transporting layer (on the anode side) and a second electron transporting layer (on the cathode side). In one embodiment of the present invention, the electron transporting layer having the single-layer structure is preferably adjacent to the light emitting layer, and the electron transporting layer closest to the anode in the multilayer structure, which is, for example, the first electron transporting layer in the two-layer structure, is preferably adjacent to the light emitting layer. In another embodiment of the present invention, a hole blocking layer, which will be described later, may be interposed between the electron transporting layer and the light emitting layer in the single-layer structure, or between the electron transporting layer and the light emitting layer closest to the light emitting layer in the multilayer structure.
In the electron transporting layer,
Examples of the metal complex include tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), tris(4-methyl-8-quinolinolato)aluminum(abbreviation: Almq3), bis(10-hydroxybenzo[h]quinolinato) beryllium (abbreviation: BeBq2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ).
Examples of the heteroaromatic compound include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(ptert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ), bathophenanthroline (abbreviation: BPhen), bathocuproine (abbreviation: BCP), and 4,4′-bis(5-methylbenzoxazol-2-yl) stilbene (abbreviation: BzOs).
Examples of the high molecular weight compound include 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).
The material has an electron mobility of 10−6 cm2/Vs or more. Note that materials other than those mentioned above may be used for the electron transporting layer as long as they have higher electron transport properties than hole transport properties.
The electron injecting layer is a layer containing a material having high electron injection properties. In the electron injecting layer, alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as magnesium (Mg), calcium (Ca), and strontium (Sr), rare earth metals such as a europium (Eu), and ytterbium (Yb), and compounds containing these metals, can be used. Examples of such compounds include alkali metal oxides, alkali metal halides, alkali metal-containing organic complexes, alkaline earth metal oxides, alkaline earth metal halides, alkaline earth metal-containing organic complexes, rare earth metal oxides, rare earth metal halides, and rare earth metal-containing organic complexes. Further, a plurality of these compounds can also be used in combination.
In addition, a material having an electron transport property in which alkali metals, alkaline earth metals, or compounds thereof are contained, specifically, the Alq in which magnesium (Mg) is contained, may be used. Note that in this case, the electron injection from the cathode can be effectively performed.
Alternatively, a composite material formed by mixing an organic compound and an electron donor (donor) in the electron injecting layer. Such a composite material has excellent electron injection properties and electron transport properties since the organic compound receives electrons from an electron donor. In this case, the organic compound is preferably a material which is excellent in transporting received electrons, and specifically, for example, the above-mentioned materials constituting the electron transporting layer (metal complexes, heteroaromatic compounds, etc.) can be used. The electron donor may be any material as long as it exhibits electron donating properties to organic compounds. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferred, and examples thereof include lithium, cesium, magnesium, calcium, erbium, and ytterbium. Moreover, alkali metal oxides and alkaline earth metal oxides are preferred, and examples thereof include lithium oxide, calcium oxide, and barium oxide. In addition, Lewis bases such as magnesium oxide can also be used. Moreover, organic compounds such as tetrathiafulvalene (abbreviation: TTF) can also be used.
For the cathode, it is preferable to use a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a small work function (specifically, 3.8 eV or less). Specific examples of the cathode material include elements belonging to Group 1 or Group 2 of the Periodic Table of Elements, that is, alkali metals such as lithium (Li) and cesium (Cs), and alkaline earth metals such as magnesium (Mg), calcium (Ca), and strontium (Sr), alloys containing these (for example, MgAg, AlLi), rare earth metals such as europium (Eu), ytterbium (Yb), and alloys containing these.
In addition, when forming a cathode using an alkali metal, an alkaline earth metal, or an alloy containing these, a vacuum deposition method or a sputtering method can be used. Furthermore, when silver paste or the like is used, a coating method, an inkjet method, or the like can be used.
By providing an electron injecting layer, the cathode can be formed using various conductive materials such as Al, Ag, ITO, graphene, and indium oxide-tin oxide containing silicon or silicon oxide, no matter how large or small the work function is. These conductive materials can be film-formed by using a sputtering method, an inkjet method, a spin coating method, or the like.
Since organic EL devices apply an electric field to an ultra-thin film, pixel defects are likely to occur due to leakage or short circuits. In order to prevent this, an insulating layer made of an insulating thin film layer may be inserted between a pair of electrodes.
Examples of materials used for the insulating layer include aluminum oxide, lithium fluoride, lithium oxide, cesium fluoride, cesium oxide, magnesium oxide, magnesium fluoride, calcium oxide, calcium fluoride, aluminum nitride, titanium oxide, silicon oxide, germanium oxide, silicon nitride, boron nitride, molybdenum oxide, ruthenium oxide, and vanadium oxide. Note that a mixture or a laminate of these may also be used.
The space layer is a layer provided between, for example, when laminating a fluorescent layer and a phosphorescent layer, the fluorescent light emitting layer and the phosphorescent light emitting layer, in order to prevent excitons generated in the phosphorescent layer from diffusing into the fluorescent layer or to adjust the carrier balance, for example. Moreover, the space layer can also be provided between plural phosphorescent light emitting layers.
Since the space layer is provided between the light emitting layers, the material for the space layer preferably has both electron transporting properties and hole transporting properties. Further, in order to prevent triplet energy from diffusing in adjacent phosphorescent light emitting layers, the triplet energy of the material is preferably 2.6 eV or more. Examples of the material used for the space layer include the same materials as those used for the hole transporting layer described above.
Blocking layers such as an electron blocking layer, a hole blocking layer, and an exciton blocking layer may be provided adjacent to the light emitting layer. The electron blocking layer is a layer which prevents electrons from leaking from the light emitting layer to the hole transporting layer, and the hole blocking layer is a layer which prevents holes from leaking from the light emitting layer to the electron transporting layer. The exciton blocking layer has the function of preventing excitons generated in the light emitting layer from diffusing into surrounding layers and confining the excitons within the light emitting layer.
Each layer of the organic EL device can be formed by a conventionally known vapor deposition method, coating method, or the like. For example, vapor deposition methods such as vacuum deposition method and molecular beam evaporation method (MBE method), or known coating methods such as dipping method, spin coating method, casting method, bar coating method, and roll coating method which use a solution of a compound forming a layer, can be used for forming.
The film thickness of each layer is not particularly limited, however in general, when the film thickness is too thin, defects such as pinholes are likely to occur, and on the other hand, when the film thickness is too thick, a high drive voltage will be required and efficiency will deteriorate, therefore it is usually 5 nm to 10 μm, more preferably 10 nm to 0.2 μm.
In the organic EL device having the hole transporting layer having the two-layer structure or the three-layer structure of the present invention, the total of the thickness of the first hole transporting layer and the thickness of the second hole transporting layer is preferably 30 nm or more and 150 nm or less, more preferably 40 nm or more and 130 nm or less.
Further, in one embodiment of the present invention, the thickness of the second hole transporting layer having the two-layer structure or the three-layer structure is preferably 5 nm or more, more preferably 20 nm or more, further preferably 25 nm or more, particularly preferably 35 nm or more, and preferably 100 nm or less.
Further, in one embodiment of the present invention, the thickness of the hole transporting layer which is adjacent to the light emitting layer is preferably 5 nm or more, more preferably 20 nm or more, further preferably 25 nm or more, particularly preferably 30 nm or more, and preferably 100 nm or less.
Further, in the organic EL device having the hole transporting layer having the two-layer structure or the three-layer structure according to the present invention, the ratio of the film thickness D2 of the second hole transporting layer to the film thickness D1 of the first hole transporting layer is preferably 0.3<D2/D1<4.0, more preferably 0.5<D2/D1<3.5, further preferably 0.75<D2/D1<3.0.
Preferred embodiments of the organic EL device of the present invention include, for example,
The organic EL device can be used in display parts such as organic EL panel modules, display devices such as televisions, mobile phones, and personal computers, and electronic devices such as lighting and light emitting devices of vehicle lamps.
Hereinafter, the present invention will be described in more detail by the following examples, however the present invention is not limited to the following examples.
Inventive compounds used for producing the organic EL devices of Examples 1 to 7
Comparative compounds used for producing the organic EL devices of Comparative examples 1 to 3
Other compounds used for producing the organic EL devices of Examples 1 to 7 and the Comparative examples 1 to 3
A 25 mm×75 mm×1.1 mm glass substrate (manufactured by Geomatec Co., Ltd.) with an ITO transparent electrode (anode) was ultrasonically washed in isopropyl alcohol for 5 minutes and then UV ozone washed for 30 minutes. The film thickness of ITO was 130 nm.
The glass substrate with an ITO transparent electrode after washing was mounted on a substrate holder of a vacuum evaporation device.
First, a compound HT-1 and a compound HI-1 were vapor co-deposited onto the surface on which the transparent electrode was formed so as to cover the transparent electrode, to form a hole injecting layer with a film thickness of 10 nm. The mass ratio of the compound HT-1 and the compound HI-1 (HT-1: HI-1) was 97:3.
Next, the compound HT-1 was vapor-deposited on the hole injecting layer to form a first hole transporting layer with a film thickness of 40 nm.
Next, the inventive compound Inv-1 was vapor-deposited on the first hole transporting layer to form a second hole transporting layer with a film thickness of 40 nm.
Next, the compound HT-2 was vapor-deposited on the second hole transporting layer to form a third hole transporting layer with a film thickness of 5 nm.
Next, a compound BH-1 (host material) and a compound BD-1 (dopant material) were vapor co-deposited onto the third hole transporting layer to form a light emitting layer with a film thickness of 20 nm. The mass ratio of the compound BH-1 and the compound BD-1 (BH-1: BD-1) was 99:1.
Next, on the light emitting layer, compound ET-1 was vapor-deposited to form a first electron transporting layer with a film thickness of 5 nm.
Next, the compound ET-2 and Liq were vapor co-deposited on the first electron transporting layer to form a second electron transporting layer with a film thickness of 25 nm. The mass ratio of compound ET-2 and Liq (ET-2: Liq) was 50:50.
Next, Yb was vapor-deposited on the second electron transporting layer to form an electron injecting electrode having a film thickness of 1 nm.
Then, metal Al was vapor-deposited on this electron injecting electrode to form a metal cathode with a film thickness of 50 nm.
The layer configuration of the organic EL device obtained by this manner is shown below.
ITO (130)/HT-1:HI-1=97:3 (10)/HT-1 (40)/Inv-1 (40)/HT-2 (5)/BH-1:BD-1=99:1 (20)/ET-1 (5)/ET-2:Liq=50:50 (25)/Yb (1)/Al (50)
In the above layer configuration, the numbers in parentheses are film thicknesses (nm), and the ratios are mass ratios.
An organic EL device was prepared in the same manner as in Example 1, except that the comparative compound Ref-1 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the inventive compound Inv-2 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the inventive compound Inv-3 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the inventive compound Inv-4 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the inventive compound Inv-6 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the inventive compound Inv-7 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the inventive compound Inv-8 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the comparative compound Ref-2 was used instead of inventive compound Inv-1.
An organic EL device was prepared in the same manner as in Example 1, except that the comparative compound Ref-3 was used instead of inventive compound Inv-1.
The voltage (V) was measured when a voltage was applied to the organic EL device so that the current density was 10 mA/cm2. The results are shown in Table 1.
The obtained organic EL device was driven at constant DC current at a current density of 10 mA/cm2 at room temperature. Luminance was measured using a luminance meter (Spectroluminance radiometer CS-1000 manufactured by Minolta Co., Ltd.), and the external quantum efficiency (%) was determined from the results. The results are shown in Table 1.
As is clear from the results in Table 1, the inventive compounds Inv-1 to Inv-4 and Inv-6 to Inv-8 provide an organic EL device which is driven at a lower voltage and has higher external quantum efficiency than the comparative compounds Ref−1 to Ref-3.
Under an argon atmosphere, a mixture of 1-bromo-2-iodobenzene (11.37 g, 40.2 mmol), 2-biphenylboronic acid (6.58 g, 33.2 mmol), bis(triphenylphosphine)palladium(II) dichloride (1.16 G, 1.66 mmol), sodium carbonate (19.02 g, 179 mmol), DME (200 mL), ethanol (8 mL) and water (90 mL) was stirred at 80° C. for 7 hours. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography to obtain Intermediate A as a colorless liquid (8.05 g). The yield was 78%.
A mixture of the obtained intermediate A (8.05 g, 26 mmol), 2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) aniline (5.99 g, 27.3 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.238 g, 0.26 mmol), 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (Xphos) (0.496 g, 1.04 mmol), tripotassium phosphate (16.58 g, 78 mmol), 1,4-dioxane (174 mL) and water (39 mL) was stirred at 100° C. for 5 hours under an argon atmosphere. The reaction solution was cooled to room temperature, water was added, and then concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography to obtain Intermediate B as a pale yellow solid (8.28 g). The yield was 99%.
Under argon atmosphere, a mixture of the intermediate B (3.37 g, 10.48 mmol), 4-bromobiphenyl (2.44 g, 10.48 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.192 g, 0.210 mmol)), BINAP (0.261 g, 0.419 mmol), sodium-t-butoxide (1.41 g, 14.68 mmol), and toluene (70 mL) were stirred at 100° C. for 3 hours. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography and recrystallization to obtain 4.66 g of Intermediate C as a white solid. The yield was 94%.
The intermediate D was obtained by performing the same operation as in Intermediate Synthesis Example 3, except that 2-bromo-9,9-dimethyl-9H-fluorene was used instead of 4-bromobiphenyl used in Intermediate synthesis example 3. The yield was 91%.
The intermediate E was obtained by performing the same procedure as in Intermediate synthesis example 3, except that bromobenzene was used instead of 4-bromobiphenyl used in Intermediate synthesis example 3. The yield was 91%.
A mixture of the intermediate C (3.8 g, 8.02 mmol), 2′-bromospiro[adamantane-2,9′-fluorene] (3.22 g, 8.83 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.147 g, 0.160 mmol), tri-t-butylphosphonium tetrafluoroborate (0.186 g, 0.642 mmol), sodium-t-butoxide (1.079 g, 11.23 mmol), and xylene (54 mL) was stirred at 120° C. for 5 hours. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography and recrystallization to obtain 3.08 g of Intermediate C as a white solid. The obtained white solid was compound Inv-1 as a result of mass spectrometry analysis (m/e=757 for molecular weight 757.37).
A compound was obtained by performing the same operation as in Synthesis Example 1, except that 2′-bromospiro[cyclohexane-1,9′-fluorene] was used instead of 2′-bromospiro[adamantane-2,9′-fluorene] used in Synthesis Example 1. The obtained compound was the compound Inv-2 as a result of mass spectrometry analysis (m/e-705 for molecular weight 705.34).
A compound was obtained by performing the same operation as in Synthesis Example 1, except that 2-bromo-9,9-dimethyl-9H-fluorene was used instead of 2′-bromospiro[adamantane-2,9′-fluorene] used in Synthesis Example 1. The obtained compound was the compound Inv-3 as a result of mass spectrometry analysis (m/e-665 for molecular weight 665.31).
A compound was obtained by performing the same operation as in Synthesis Example 1 except that Intermediate D was used in place of Intermediate C used in Synthesis Example 1. The obtained compound was the compound Inv-4 as a result of mass spectrometry analysis (m/e-797 for molecular weight 797.40).
A compound was obtained by performing the same operation as in Synthesis Example 1, except that the intermediate E was used instead of the intermediate C used in Synthesis Example 1, and 2′-bromo-2,7-di-tert-butyl-9,9′-spirobi[fluorene] instead of 2′-bromospiro[adamantane-2,9′-fluorene]. The obtained compound was compound Inv-5 as a result of mass spectrometry analysis (m/e-823 for molecular weight 823.42).
A compound was obtained by performing the same operation as in Synthesis Example 1, except that 2-bromo-9,9-diphenylfluorene was used instead of 2′-bromospiro[adamantane-2,9′-fluorene] used in Synthesis Example 1. The obtained compound was compound Inv-6 as a result of mass spectrometry analysis (m/e=790 for molecular weight 790.02).
A mixture of the intermediate B (2.7 g, 8.4 mmol), 2-bromo-9,9-dimethylfluorene (5.736 g, 21 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.154 g, 0.168 mmol), tri-t-butylphosphonium tetrafluoroborate (0.195 g, 0.672 mmol), sodium-t-butoxide (2.260 g, 23.52 mmol), and xylene (56 mL) was stirred at 120° C. for 5 hours. The reaction solution was cooled to room temperature and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography and recrystallization to obtain 4.03 g of a white solid. The yield was 68%.
As a result of mass spectrometry analysis (m/e=705 for molecular weight 705.34), the obtained product was compound Inv-7.
A compound was obtained by performing the same operation as in Synthesis Example 4, except that 4-(4-bromophenyl)dibenzofuran was used instead of 2′-bromospiro[adamantane-2,9′-fluorene] used in Synthesis Example 4. The obtained compound was the compound Inv-8 as a result of mass spectrometry analysis (m/e=755 for molecular weight 755.96).
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-008248 | Jan 2022 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2023/001326 | 1/18/2023 | WO |
