Organic electroluminescent element and electronic device
The organic electroluminescence element addresses the efficiency limitations of existing EL elements by incorporating specific compounds to utilize both singlet and triplet excitons, resulting in improved luminance and lifespan.
Patent Information
- Application Number
- PCT/JP2025/010949
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-03-29
- Filing Date
- 2025-03-21
- Publication Date
- 2025-10-02
AI Technical Summary
Existing organic electroluminescence (EL) elements are limited by an internal quantum efficiency of 25% due to the utilization of singlet excitons, and there is a need for improved performance in luminance, emission wavelength, chromaticity, luminous efficiency, driving voltage, and lifespan.
An organic electroluminescence element comprising an anode, cathode, and an emitting layer with specific compounds, including a fluorescent compound and a delayed fluorescent compound, with defined mass content and electron mobility ranges, to enhance light emission efficiency by utilizing both singlet and triplet excitons.
The proposed element achieves long lifetime light emission and improved performance in electronic devices by effectively utilizing both singlet and triplet excitons, enhancing efficiency and durability.
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Figure JP2025010949_02102025_PF_FP_ABST
Abstract
Description
Organic electroluminescence element and electronic device
[0001] The present invention relates to an organic electroluminescence element and an electronic device.
[0002] When a voltage is applied to an organic electroluminescence element (hereinafter sometimes referred to as an "organic EL element"), holes are injected from the anode into the light-emitting layer, and electrons are injected from the cathode into the light-emitting layer. The injected holes and electrons then recombine in the light-emitting layer to form excitons. According to the statistical law of electron spin, singlet excitons are generated at a rate of 25% and triplet excitons at a rate of 75%. Fluorescent organic EL elements that utilize light emission from singlet excitons are increasingly being applied to full-color displays such as those for mobile phones and televisions, but their internal quantum efficiency is said to be limited to 25%. Therefore, efforts are being made to improve the performance of organic EL elements.
[0003] For example, it is expected that organic EL elements will emit light more efficiently by utilizing triplet excitons in addition to singlet excitons. Against this background, highly efficient fluorescent organic EL elements utilizing thermally activated delayed fluorescence (hereinafter sometimes simply referred to as "delayed fluorescence") have been proposed and studied. The TADF (thermally activated delayed fluorescence) mechanism utilizes the phenomenon in which reverse intersystem crossing from triplet excitons to singlet excitons occurs thermally when a material with a small energy difference (ΔST) between the singlet and triplet levels is used. Thermally activated delayed fluorescence is described, for example, in "Device Properties of Organic Semiconductors," edited by Adachi Chinaya, Kodansha, published April 1, 2012, pp. 261-268. Known compounds that exhibit thermally activated delayed fluorescence (TADF) properties include, for example, compounds in which a donor moiety and an acceptor moiety are bound within the molecule.
[0004] For example, Patent Documents 1 and 2 describe organic EL devices having an emitting layer containing a delayed fluorescent compound, and Patent Documents 1 and 2 also describe the inclusion of two types of host materials in the emitting layer together with the delayed fluorescent compound.
[0005] JP 2021-197438 A JP 2021-197439 A
[0006] In order to improve the performance of electronic devices such as displays, there is a demand for further improvements in the performance of organic EL elements, such as luminance, emission wavelength, chromaticity, luminous efficiency, driving voltage, and lifespan.
[0007] An object of the present invention is to provide an organic electroluminescent element that emits light with a long life, and to provide an electronic device equipped with the organic electroluminescent element.
[0008] According to one aspect of the present invention, there is provided an organic electroluminescence device comprising an anode, a cathode, and an emitting layer between the anode and the cathode, wherein the emitting layer contains a first compound, a second compound, a third compound, and a fourth compound, the first compound, the second compound, the third compound, and the fourth compound are different from one another, the first compound is a fluorescent compound, the second compound is a delayed fluorescent compound, the content of the second compound in the emitting layer is 30% by mass or more and 50% by mass or less, and the third compound and the fourth compound satisfy the following mathematical formulas (Mathematical Formula 1), (Mathematical Formula 2), and (Mathematical Formula 3): (Mathematical Formula 1): 0.08 eV≦|HOMO(M3)−HOMO(M4)|≦0.22 eV (Mathematical Formula 2): μE(M3)≦5.0×10 -7 cm 2 / Vs (Math 3): μE (M4)≦5.0×10 -7 cm 2 / Vs (HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound, μE(M3) is the electron mobility of the third compound, and μE(M4) is the electron mobility of the fourth compound).
[0009] According to one aspect of the present invention, there is provided an electronic device equipped with the organic electroluminescence element according to one aspect of the present invention.
[0010] According to one aspect of the present invention, it is possible to provide an organic electroluminescence element that emits light with a long lifetime, and an electronic device equipped with the organic electroluminescence element.
[0011] 1 is a diagram showing a schematic configuration of an example of an organic electroluminescence element according to a first embodiment of the present invention; 2 is a diagram showing a schematic configuration of another example of an organic electroluminescence element according to the first embodiment of the present invention; 3 is a diagram showing a schematic diagram of an apparatus for measuring transient PL; 4 is a diagram showing an example of a decay curve of transient PL; 5 is a diagram showing the energy levels of a first compound, a second compound, a third compound, and a fourth compound in an emitting layer of an example of an organic electroluminescence element according to a first embodiment of the present invention, and the relationship between energy transfer; 6 is a diagram showing the energy levels of a second compound, a third compound, and a fourth compound in an emitting layer of an example of an organic electroluminescence element according to a second embodiment of the present invention, and the relationship between energy transfer.
[0012] [Definitions] In this specification, hydrogen atoms include isotopes with different numbers of neutrons, namely protium, deuterium, and tritium.
[0013] In this specification, in a chemical structural formula, a hydrogen atom, that is, a protium atom, a deuterium atom, or a tritium atom is assumed to be bonded to a possible bonding position that is not explicitly indicated with a symbol such as "R" or "D" representing a deuterium atom.
[0014] As used herein, the term "number of ring carbon atoms" refers to the number of carbon atoms among the atoms constituting the ring itself of a compound having a structure in which atoms are bonded in a ring (e.g., a monocyclic compound, a fused ring compound, a bridged compound, a carbocyclic compound, and a heterocyclic compound). When the ring is substituted with a substituent, the carbon atoms contained in the substituent are not included in the number of ring carbon atoms. The "number of ring carbon atoms" described below is the same unless otherwise specified. 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, a 9,9-diphenylfluorenyl group has 13 ring carbon atoms, and a 9,9'-spirobifluorenyl group has 25 ring carbon atoms. When a benzene ring is substituted with, for example, an alkyl group 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. Therefore, the number of ring carbon atoms of a benzene ring substituted with an alkyl group is 6. Furthermore, when the naphthalene ring is substituted with, for example, an alkyl group 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. Therefore, the number of ring carbon atoms of the naphthalene ring substituted with an alkyl group is 10.
[0015] In this specification, the number of ring atoms refers to the number of atoms constituting the ring itself of a compound (e.g., a monocyclic compound, a fused ring compound, a bridged compound, a carbocyclic compound, and a heterocyclic compound) having a structure in which atoms are bonded in a ring (e.g., a monocyclic ring, a fused ring, and a ring assembly). Atoms that do not constitute the ring (e.g., hydrogen atoms terminating the bonds of atoms constituting the ring) and atoms contained in the substituent when the ring is substituted with a substituent are not included in the number of ring atoms. The "number of ring atoms" described below is the same unless otherwise specified. For example, the number of ring atoms of a pyridine ring is 6, the number of ring atoms of a quinazoline ring is 10, and the number of ring atoms of a furan ring is 5. For example, the number of hydrogen atoms or atoms constituting a substituent bonded to the pyridine ring is not included in the number of pyridine ring atoms. Therefore, the number of ring atoms of a pyridine ring to which a hydrogen atom or a substituent is bonded is 6. Furthermore, for example, hydrogen atoms bonded to carbon atoms of the quinazoline ring or atoms constituting substituents are not included in the number of ring atoms of the quinazoline ring, so the number of ring atoms of a quinazoline ring to which a hydrogen atom or a substituent is bonded is 10.
[0016] In this specification, the "number of carbon atoms XX to YY" in the expression "substituted or unsubstituted ZZ group having carbon atoms XX to YY" represents the number of carbon atoms when the ZZ group is unsubstituted, and does not include the number of carbon atoms of the substituent when the ZZ group is substituted. Here, "YY" is larger than "XX", "XX" means an integer of 1 or more, and "YY" means an integer of 2 or more.
[0017] In this specification, the "number of atoms XX to YY" in the expression "substituted or unsubstituted ZZ group having number of atoms XX to YY" refers to the number of atoms when the ZZ group is unsubstituted, and does not include the number of atoms of substituents when the ZZ group is substituted. Here, "YY" is larger than "XX", "XX" means an integer of 1 or more, and "YY" means an integer of 2 or more.
[0018] In this specification, an unsubstituted ZZ group refers to the case where a "substituted or unsubstituted ZZ group" is an "unsubstituted ZZ group", and a substituted ZZ group refers to the case where a "substituted or unsubstituted ZZ group" is a "substituted ZZ group". In this specification, "unsubstituted" in the case of a "substituted or unsubstituted ZZ group" means that a hydrogen atom in the ZZ group is not replaced with a substituent. The hydrogen atom in the "unsubstituted ZZ group" is a protist atom, a deuterium atom, or a tritium atom. Furthermore, in this specification, "substituted" in the case of a "substituted or unsubstituted ZZ group" means that one or more hydrogen atoms in the ZZ group are replaced with a substituent. Similarly, "substituted" in the case of a "BB group substituted with an AA group" means that one or more hydrogen atoms in the BB group are replaced with an AA group.
[0019] "Substituents Described in This Specification" The substituents described in this specification are explained below.
[0020] The number of ring carbon atoms of an "unsubstituted aryl group" described herein is 6 to 50, preferably 6 to 30, and more preferably 6 to 18, unless otherwise specified herein. The number of ring atoms of an "unsubstituted heterocyclic group" described herein is 5 to 50, preferably 5 to 30, and more preferably 5 to 18, unless otherwise specified herein. The number of carbon atoms of an "unsubstituted alkyl group" described herein is 1 to 50, preferably 1 to 20, and more preferably 1 to 6, unless otherwise specified herein. The number of carbon atoms of an "unsubstituted alkenyl group" described herein is 2 to 50, preferably 2 to 20, and more preferably 2 to 6, unless otherwise specified herein. The number of carbon atoms of an "unsubstituted alkynyl group" described herein is 2 to 50, preferably 2 to 20, and more preferably 2 to 6, unless otherwise specified herein. The number of ring carbon atoms of an "unsubstituted cycloalkyl group" described herein is 3 to 50, preferably 3 to 20, and more preferably 3 to 6, unless otherwise specified herein. Unless otherwise specified herein, the number of ring carbon atoms of an "unsubstituted arylene group" described herein is 6 to 50, preferably 6 to 30, and more preferably 6 to 18. Unless otherwise specified herein, the number of ring atoms of an "unsubstituted divalent heterocyclic group" described herein is 5 to 50, preferably 5 to 30, and more preferably 5 to 18. Unless otherwise specified herein, the number of carbon atoms of an "unsubstituted alkylene group" described herein is 1 to 50, preferably 1 to 20, and more preferably 1 to 6.
[0021] "Substituted or Unsubstituted Aryl Group" Specific examples (Specific Example Group G1) of the "substituted or unsubstituted aryl group" described herein include the following unsubstituted aryl group (Specific Example Group G1A) and substituted aryl group (Specific Example Group G1B). (Here, an unsubstituted aryl group refers to a case where a "substituted or unsubstituted aryl group" is an "unsubstituted aryl group," and a substituted aryl group refers to a case where a "substituted or unsubstituted aryl group" is a "substituted aryl group.") In this specification, the term "aryl group" simply refers to both an "unsubstituted aryl group" and a "substituted aryl group." A "substituted aryl group" refers to a group in which one or more hydrogen atoms of an "unsubstituted aryl group" are replaced with substituents. Examples of the "substituted aryl group" include a group in which one or more hydrogen atoms of an "unsubstituted aryl group" are replaced with substituents in the "unsubstituted aryl group" of the following Specific Example Group G1A, and examples of the substituted aryl group of the following Specific Example Group G1B. It should be noted that the examples of "unsubstituted aryl groups" and "substituted aryl groups" listed here are merely examples, and the "substituted aryl groups" described in this specification also include groups in which a hydrogen atom bonded to a carbon atom of the aryl group itself in the "substituted aryl groups" of the following specific example group G1B is further replaced with a substituent, and groups in which a hydrogen atom of a substituent in the "substituted aryl groups" of the following specific example group G1B is further replaced with a substituent.
[0022] Unsubstituted aryl groups (specific example group G1A): a phenyl group, a p-biphenyl group, an 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, an m-terphenyl-4-yl group, an m-terphenyl-3-yl group, an 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 benzanthryl group, a phenanthryl group, a benzophenanthryl group, a phenalenyl group, a pyrenyl group, a chrysenyl group, a benzochrysenyl group, a triphenylenyl group, a benzotriphenylenyl group, a tetracenyl group, a pentacenyl group, a fluorenyl group, A 9,9'-spirobifluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a fluoranthenyl group, a benzofluoranthenyl group, a perylenyl group, and a monovalent aryl group derived by removing one hydrogen atom from a ring structure represented by the following general formulas (TEMP-1) to (TEMP-15).
[0023]
[0024]
[0025] Substituted aryl groups (specific example group G1B): o-tolyl group, m-tolyl group, p-tolyl group, para-xylyl group, meta-xylyl group, ortho-xylyl group, para-isopropylphenyl group, meta-isopropylphenyl group, ortho-isopropylphenyl group, para-t-butylphenyl group, meta-t-butylphenyl group, ortho-t-butylphenyl group, 3,4,5-trimethylphenyl group, 9,9-dimethylfluorenyl group, 9,9-diphenylfluorenyl group, 9,9-bis(4-methylphenyl)fluorenyl group, 9,9-bis(4-isopropylphenyl)fluorenyl group, 9,9-bis(4-t-butylphenyl)fluorenyl group, cyanophenyl group, triphenylsilylphenyl group, trimethylsilylphenyl group, phenylnaphthyl group, naphthylphenyl group, and A group in which one or more hydrogen atoms of a monovalent group derived from a ring structure represented by the above general formulae (TEMP-1) to (TEMP-15) are replaced with a substituent.
[0026] "Substituted or Unsubstituted Heterocyclic Group" The "heterocyclic group" described herein is a cyclic group containing at least one heteroatom among the ring-forming atoms. Specific examples of the heteroatom include a nitrogen atom, an oxygen atom, a sulfur atom, a silicon atom, a phosphorus atom, and a boron atom. The "heterocyclic group" described herein is a monocyclic group or a fused ring group. The "heterocyclic group" described herein is an aromatic heterocyclic group or a non-aromatic heterocyclic group. Specific examples (specific example group G2) of the "substituted or unsubstituted heterocyclic group" described herein include the following unsubstituted heterocyclic group (specific example group G2A) and substituted heterocyclic group (specific example group G2B). (Here, an unsubstituted heterocyclic group refers to when a "substituted or unsubstituted heterocyclic group" is an "unsubstituted heterocyclic group", and a substituted heterocyclic group refers to when a "substituted or unsubstituted heterocyclic group" is a "substituted heterocyclic group".) In this specification, when simply referring to a "heterocyclic group", it includes both an "unsubstituted heterocyclic group" and a "substituted heterocyclic group". A "substituted heterocyclic group" means a group in which one or more hydrogen atoms of an "unsubstituted heterocyclic group" are replaced with substituents. Specific examples of the "substituted heterocyclic group" include groups in which hydrogen atoms of an "unsubstituted heterocyclic group" in the following specific example group G2A are replaced, and examples of substituted heterocyclic groups in the following specific example group G2B. The examples of "unsubstituted heterocyclic groups" and "substituted heterocyclic groups" listed here are merely examples, and the "substituted heterocyclic groups" described in this specification also include groups in which a hydrogen atom bonded to a ring-forming atom of the heterocyclic group itself in the "substituted heterocyclic groups" of specific example group G2B is further replaced with a substituent, and groups in which a hydrogen atom of a substituent in the "substituted heterocyclic groups" of specific example group G2B is further replaced with a substituent.
[0027] Specific example group G2A includes, for example, the following unsubstituted heterocyclic groups containing a nitrogen atom (specific example group G2A1), unsubstituted heterocyclic groups containing an oxygen atom (specific example group G2A2), unsubstituted heterocyclic groups containing a sulfur atom (specific example group G2A3), and monovalent heterocyclic groups derived by removing one hydrogen atom from ring structures represented by the following general formulae (TEMP-16) to (TEMP-33) (specific example group G2A4).
[0028] Specific example group G2B includes, for example, the following substituted heterocyclic groups containing a nitrogen atom (specific example group G2B1), substituted heterocyclic groups containing an oxygen atom (specific example group G2B2), substituted heterocyclic groups containing a sulfur atom (specific example group G2B3), and groups in which one or more hydrogen atoms of a monovalent heterocyclic group derived from a ring structure represented by the following general formulae (TEMP-16) to (TEMP-33) are replaced with substituents (specific example group G2B4).
[0029] Unsubstituted heterocyclic groups containing a nitrogen atom (specific example group G2A1): a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, an isothiazolyl group, a thiadiazolyl group, a pyridyl group, a pyridazinyl group, a pyrimidinyl group, a pyrazinyl group, a triazinyl 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, an indazolyl group, a phenanthrolinyl group, a phenanthridinyl group, an acridinyl group, a phenazinyl group, a carbazolyl group, Benzocarbazolyl group, morpholino group, phenoxazinyl group, phenothiazinyl group, azacarbazolyl group, and diazacarbazolyl group.
[0030] Unsubstituted heterocyclic groups containing an oxygen atom (specific example group G2A2): a furyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a xanthenyl group, a benzofuranyl group, an isobenzofuranyl group, a dibenzofuranyl group, a naphthobenzofuranyl group, a benzoxazolyl group, a benzisoxazolyl group, a phenoxazinyl group, a morpholino group, a dinaphthofuranyl group, an azadibenzofuranyl group, a diazadibenzofuranyl group, an azanaphthobenzofuranyl group, and a diazanaphthobenzofuranyl group.
[0031] Unsubstituted heterocyclic groups containing a sulfur atom (specific example group G2A3): a thienyl group, a thiazolyl group, an isothiazolyl group, a thiadiazolyl group, a benzothiophenyl group (benzothienyl group), an isobenzothiophenyl group (isobenzothienyl group), a dibenzothiophenyl group (dibenzothienyl group), a naphthobenzothiophenyl group (naphthobenzothienyl group), a benzothiazolyl group, a benzisothiazolyl group, a phenothiazinyl group, a dinaphthothiophenyl group (dinaphthothienyl group), an azadibenzothiophenyl group (azadibenzothienyl group), a diazadibenzothiophenyl group (diazadibenzothienyl group), an azanaphthobenzothiophenyl group (azanaphthobenzothienyl group), and a diazanaphthobenzothiophenyl group (diazanaphthobenzothienyl group).
[0032] Monovalent heterocyclic groups derived by removing one hydrogen atom from the ring structures represented by the following general formulae (TEMP-16) to (TEMP-33) (specific example group G2A4):
[0033]
[0034]
[0035] In the general formulae (TEMP-16) to (TEMP-33), X A and Y A are each independently an oxygen atom, a sulfur atom, NH, or CH 2 However, X A and Y A At least one of X is an oxygen atom, a sulfur atom, or NH. A and Y A At least one of the groups is NH or CH 2 In this case, the monovalent heterocyclic group derived from the ring structure represented by the general formulae (TEMP-16) to (TEMP-33) may contain any of these NH, CH 2 and monovalent groups obtained by removing one hydrogen atom from the group consisting of:
[0036] Substituted heterocyclic groups containing a nitrogen atom (specific example group G2B1): a (9-phenyl)carbazolyl group, a (9-biphenylyl)carbazolyl group, a (9-phenyl)phenylcarbazolyl group, a (9-naphthyl)carbazolyl group, a diphenylcarbazol-9-yl group, a phenylcarbazol-9-yl group, a methylbenzimidazolyl group, an ethylbenzimidazolyl group, a phenyltriazinyl group, a biphenylyltriazinyl group, a diphenyltriazinyl group, a phenylquinazolinyl group, and a biphenylylquinazolinyl group.
[0037] Substituted heterocyclic groups containing an oxygen atom (specific example group G2B2): a phenyldibenzofuranyl group, a methyldibenzofuranyl group, a t-butyldibenzofuranyl group, and a monovalent residue of spiro[9H-xanthene-9,9'-[9H]fluorene].
[0038] Substituted heterocyclic groups containing a sulfur atom (specific example group G2B3): a phenyldibenzothiophenyl group, a methyldibenzothiophenyl group, a t-butyldibenzothiophenyl group, and a monovalent residue of spiro[9H-thioxanthene-9,9'-[9H]fluorene].
[0039] Groups in which one or more hydrogen atoms of a monovalent heterocyclic group derived from a ring structure represented by the above general formulae (TEMP-16) to (TEMP-33) are replaced with a substituent (specific example group G2B4):
[0040] The "one or more hydrogen atoms of the monovalent heterocyclic group" refers to a hydrogen atom bonded to a ring-forming carbon atom of the monovalent heterocyclic group, X A and Y A a hydrogen atom bonded to a nitrogen atom when at least one of A and Y A One of them is CH 2 and n is 0 or more. The methylene group in the formula (I) is one or more hydrogen atoms selected from the hydrogen atoms of the methylene group in the formula (I).
[0041] "Substituted or Unsubstituted Alkyl Group" Specific examples (Specific Example Group G3) of the "substituted or unsubstituted alkyl group" described herein include the following unsubstituted alkyl group (Specific Example Group G3A) and substituted alkyl group (Specific Example Group G3B). (Here, the term "unsubstituted alkyl group" refers to the case where the "substituted or unsubstituted alkyl group" is an "unsubstituted alkyl group," and the term "substituted alkyl group" refers to the case where the "substituted or unsubstituted alkyl group" is a "substituted alkyl group.") Hereinafter, the term "alkyl group" simply refers to both an "unsubstituted alkyl group" and a "substituted alkyl group." A "substituted alkyl group" refers to a group in which one or more hydrogen atoms in an "unsubstituted alkyl group" are replaced with substituents. Specific examples of the "substituted alkyl group" include the following "unsubstituted alkyl group" (Specific Example Group G3A) in which one or more hydrogen atoms are replaced with substituents, and the examples of the substituted alkyl group (Specific Example Group G3B). In this specification, the alkyl group in an "unsubstituted alkyl group" refers to a chain-like alkyl group. Therefore, the term "unsubstituted alkyl group" includes a straight-chain "unsubstituted alkyl group" and a branched "unsubstituted alkyl group." The examples of "unsubstituted alkyl groups" and "substituted alkyl groups" listed here are merely examples, and the "substituted alkyl group" described in this specification also includes groups in which a hydrogen atom of the alkyl group itself in the "substituted alkyl group" of specific example group G3B is further replaced with a substituent, and groups in which a hydrogen atom of a substituent in the "substituted alkyl group" of specific example group G3B is further replaced with a substituent.
[0042] Unsubstituted alkyl groups (specific example group G3A): a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an s-butyl group, and a t-butyl group.
[0043] Substituted alkyl groups (specific example group G3B): a heptafluoropropyl group (including isomers), a pentafluoroethyl group, a 2,2,2-trifluoroethyl group, and a trifluoromethyl group.
[0044] "Substituted or Unsubstituted Alkenyl Group" Specific examples (Specific Example Group G4) of the "substituted or unsubstituted alkenyl group" described herein include the following unsubstituted alkenyl group (Specific Example Group G4A) and substituted alkenyl group (Specific Example Group G4B). (Here, an unsubstituted alkenyl group refers to a case where a "substituted or unsubstituted alkenyl group" is an "unsubstituted alkenyl group," and a "substituted alkenyl group" refers to a case where a "substituted or unsubstituted alkenyl group" is a "substituted alkenyl group.") In this specification, the term "alkenyl group" simply refers to both an "unsubstituted alkenyl group" and a "substituted alkenyl group." A "substituted alkenyl group" refers to a group in which one or more hydrogen atoms in an "unsubstituted alkenyl group" are replaced with substituents. Specific examples of the "substituted alkenyl group" include the following "unsubstituted alkenyl groups" (specific example group G4A) having a substituent, and examples of substituted alkenyl groups (specific example group G4B). The examples of "unsubstituted alkenyl groups" and "substituted alkenyl groups" listed here are merely examples, and the "substituted alkenyl group" described in this specification also includes groups in which a hydrogen atom of the alkenyl group itself in the "substituted alkenyl groups" of specific example group G4B is further replaced with a substituent, and groups in which a hydrogen atom of a substituent in the "substituted alkenyl groups" of specific example group G4B is further replaced with a substituent.
[0045] Unsubstituted alkenyl groups (specific example group G4A): a vinyl group, an allyl group, a 1-butenyl group, a 2-butenyl group, and a 3-butenyl group.
[0046] Substituted alkenyl groups (specific example group G4B): a 1,3-butadienyl group, a 1-methylvinyl group, a 1-methylallyl group, a 1,1-dimethylallyl group, a 2-methylallyl group, and a 1,2-dimethylallyl group.
[0047] - "Substituted or Unsubstituted Alkynyl Group" Specific examples (specific example group G5) of the "substituted or unsubstituted alkynyl group" described in this specification include the following unsubstituted alkynyl group (specific example group G5A). (Here, an unsubstituted alkynyl group refers to a case where the "substituted or unsubstituted alkynyl group" is an "unsubstituted alkynyl group.") Hereinafter, the term "alkynyl group" includes both an "unsubstituted alkynyl group" and a "substituted alkynyl group." A "substituted alkynyl group" refers to a group in which one or more hydrogen atoms in an "unsubstituted alkynyl group" have been replaced with a substituent. Specific examples of the "substituted alkynyl group" include a group in which one or more hydrogen atoms in the "unsubstituted alkynyl group" (specific example group G5A) have been replaced with a substituent.
[0048] Unsubstituted alkynyl groups (specific example group G5A): ethynyl groups.
[0049] "Substituted or Unsubstituted Cycloalkyl Group" Specific examples (Specific Example Group G6) of the "substituted or unsubstituted cycloalkyl group" described herein include the following unsubstituted cycloalkyl group (Specific Example Group G6A) and substituted cycloalkyl group (Specific Example Group G6B). (Here, the term "unsubstituted cycloalkyl group" refers to the case where the "substituted or unsubstituted cycloalkyl group" is an "unsubstituted cycloalkyl group," and the term "substituted cycloalkyl group" refers to the case where the "substituted or unsubstituted cycloalkyl group" is a "substituted cycloalkyl group.") In this specification, the term "cycloalkyl group" simply refers to both an "unsubstituted cycloalkyl group" and a "substituted cycloalkyl group." A "substituted cycloalkyl group" refers to a group in which one or more hydrogen atoms in an "unsubstituted cycloalkyl group" are replaced with substituents. Specific examples of the "substituted cycloalkyl group" include the following "unsubstituted cycloalkyl group" (Specific Example Group G6A) in which one or more hydrogen atoms are replaced with substituents, and the examples of the substituted cycloalkyl group (Specific Example Group G6B). The examples of "unsubstituted cycloalkyl groups" and "substituted cycloalkyl groups" listed here are merely examples, and the "substituted cycloalkyl groups" described in this specification also include groups in which one or more hydrogen atoms bonded to a carbon atom of the cycloalkyl group itself in the "substituted cycloalkyl groups" of specific example group G6B are replaced with substituents, and groups in which a hydrogen atom of a substituent in the "substituted cycloalkyl groups" of specific example group G6B is further replaced with a substituent.
[0050] Unsubstituted cycloalkyl groups (specific example group G6A): a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 1-adamantyl group, a 2-adamantyl group, a 1-norbornyl group, and a 2-norbornyl group.
[0051] Substituted cycloalkyl groups (specific example group G6B): 4-methylcyclohexyl group.
[0052] -Si(R 901 ) (R 902 ) (R 903 A group represented by —Si(R 901 ) (R 902) (R 903 Specific examples (specific example group G7) of the group represented by the formula (G1) include -Si(G1)(G1)(G1), -Si(G1)(G2)(G2), -Si(G1)(G1)(G2), -Si(G2)(G2)(G2), -Si(G3)(G3)(G3), and -Si(G6)(G6)(G6). Here, G1 is a "substituted or unsubstituted aryl group" described in specific example group G1. G2 is a "substituted or unsubstituted heterocyclic group" described in specific example group G2. G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3. G6 is a "substituted or unsubstituted cycloalkyl group" described in specific example group G6. The multiple G1s in -Si(G1)(G1)(G1) may be the same or different. - Multiple G2 in Si(G1)(G2)(G2) are the same as or different from each other. - Multiple G1 in Si(G1)(G1)(G2) are the same as or different from each other. - Multiple G2 in Si(G2)(G2)(G2) are the same as or different from each other. - Multiple G3 in Si(G3)(G3)(G3) are the same as or different from each other. - Multiple G6 in Si(G6)(G6)(G6) are the same as or different from each other.
[0053] ・「-O-(R 904 A group represented by —O—(R 904 ) (Specific example group G8) includes -O(G1), -O(G2), -O(G3), and -O(G6). Here, G1 is a "substituted or unsubstituted aryl group" described in specific example group G1. G2 is a "substituted or unsubstituted heterocyclic group" described in specific example group G2. G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3. G6 is a "substituted or unsubstituted cycloalkyl group" described in specific example group G6.
[0054] ・"-S-(R 905 A group represented by —S—(R 905) (Specific example group G9) includes -S(G1), -S(G2), -S(G3), and -S(G6). Here, G1 is a "substituted or unsubstituted aryl group" described in specific example group G1. G2 is a "substituted or unsubstituted heterocyclic group" described in specific example group G2. G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3. G6 is a "substituted or unsubstituted cycloalkyl group" described in specific example group G6.
[0055] ・「-N(R 906 ) (R 907 A group represented by —N(R 906 ) (R 907 Specific examples (specific example group G10) of groups represented by the formula (G1) include -N(G1)(G1), -N(G2)(G2), -N(G1)(G2), -N(G3)(G3), and -N(G6)(G6). Here, G1 is a "substituted or unsubstituted aryl group" described in specific example group G1. G2 is a "substituted or unsubstituted heterocyclic group" described in specific example group G2. G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3. G6 is a "substituted or unsubstituted cycloalkyl group" described in specific example group G6. Multiple G1s in -N(G1)(G1) may be the same as or different from one another. Multiple G2s in -N(G2)(G2) may be the same as or different from one another. Multiple G3s in -N(G3)(G3) may be the same as or different from one another. The multiple G6s in -N(G6)(G6) are the same as or different from each other.
[0056] "Halogen Atom" Specific examples (specific example group G11) of the "halogen atom" described in this specification include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
[0057] "Substituted or unsubstituted fluoroalkyl group" As used herein, a "substituted or unsubstituted fluoroalkyl group" refers to a group in which at least one hydrogen atom bonded to a carbon atom constituting the alkyl group in a "substituted or unsubstituted alkyl group" is replaced with a fluorine atom, and also includes a group in which all hydrogen atoms bonded to carbon atoms constituting the alkyl group in a "substituted or unsubstituted alkyl group" are replaced with fluorine atoms (perfluoro group). Unless otherwise specified herein, the number of carbon atoms in an "unsubstituted fluoroalkyl group" is 1 to 50, preferably 1 to 30, and more preferably 1 to 18. A "substituted fluoroalkyl group" refers to a group in which one or more hydrogen atoms of a "fluoroalkyl group" are replaced with a substituent. Note that the "substituted fluoroalkyl group" described herein also includes a group in which one or more hydrogen atoms bonded to a carbon atom of the alkyl chain in a "substituted fluoroalkyl group" are further replaced with a substituent, and a group in which one or more hydrogen atoms of a substituent in a "substituted fluoroalkyl group" are further replaced with a substituent. Specific examples of the "unsubstituted fluoroalkyl group" include the examples of the above-mentioned "alkyl group" (specific example group G3) in which one or more hydrogen atoms have been replaced with fluorine atoms.
[0058] "Substituted or unsubstituted haloalkyl group" As used herein, a "substituted or unsubstituted haloalkyl group" refers to a group in which at least one hydrogen atom bonded to a carbon atom constituting the alkyl group in a "substituted or unsubstituted alkyl group" is replaced with a halogen atom, and also includes a group in which all hydrogen atoms bonded to carbon atoms constituting the alkyl group in a "substituted or unsubstituted alkyl group" are replaced with halogen atoms. The number of carbon atoms in an "unsubstituted haloalkyl group" is 1 to 50, preferably 1 to 30, and more preferably 1 to 18, unless otherwise specified herein. A "substituted haloalkyl group" refers to a group in which one or more hydrogen atoms of a "haloalkyl group" are replaced with a substituent. Note that the "substituted haloalkyl group" described herein also includes a "substituted haloalkyl group" in which one or more hydrogen atoms bonded to a carbon atom of the alkyl chain are further replaced with a substituent, and a "substituted haloalkyl group" in which one or more hydrogen atoms of the substituent are further replaced with a substituent. Specific examples of the "unsubstituted haloalkyl group" include the examples of the above-mentioned "alkyl group" (specific example group G3) in which one or more hydrogen atoms are replaced with halogen atoms. A haloalkyl group may also be referred to as a halogenated alkyl group.
[0059] - "Substituted or unsubstituted alkoxy group" A specific example of the "substituted or unsubstituted alkoxy group" described in this specification is a group represented by -O(G3), where G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3. Unless otherwise specified in this specification, the number of carbon atoms in the "unsubstituted alkoxy group" is 1 to 50, preferably 1 to 30, and more preferably 1 to 18.
[0060] - "Substituted or unsubstituted alkylthio group" A specific example of the "substituted or unsubstituted alkylthio group" described in this specification is a group represented by -S(G3), where G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3. Unless otherwise specified in this specification, the number of carbon atoms in the "unsubstituted alkylthio group" is 1 to 50, preferably 1 to 30, and more preferably 1 to 18.
[0061] - "Substituted or unsubstituted aryloxy group" A specific example of the "substituted or unsubstituted aryloxy group" described in this specification is a group represented by -O(G1), where G1 is a "substituted or unsubstituted aryl group" described in specific example group G1. Unless otherwise specified in this specification, 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.
[0062] - "Substituted or unsubstituted arylthio group" A specific example of the "substituted or unsubstituted arylthio group" described in this specification is a group represented by -S(G1), where G1 is a "substituted or unsubstituted aryl group" described in specific example group G1. Unless otherwise specified in this specification, 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.
[0063] - "Substituted or unsubstituted trialkylsilyl group" A specific example of the "trialkylsilyl group" described in this specification is a group represented by -Si(G3)(G3)(G3), where G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3. Multiple G3s in -Si(G3)(G3)(G3) are the same as or different from one another. Unless otherwise specified in this specification, the number of carbon atoms in each alkyl group of the "trialkylsilyl group" is 1 to 50, preferably 1 to 20, and more preferably 1 to 6.
[0064] "Substituted or unsubstituted aralkyl group" A specific example of the "substituted or unsubstituted aralkyl group" described in this specification is a group represented by -(G3)-(G1), where G3 is a "substituted or unsubstituted alkyl group" described in specific example group G3, and G1 is a "substituted or unsubstituted aryl group" described in specific example group G1. Therefore, an "aralkyl group" is a group in which a hydrogen atom of an "alkyl group" is replaced with an "aryl group" as a substituent, and is one embodiment of a "substituted alkyl group." An "unsubstituted aralkyl group" is an "unsubstituted alkyl group" substituted with an "unsubstituted aryl group," and the number of carbon atoms in the "unsubstituted aralkyl group" is 7 to 50, preferably 7 to 30, and more preferably 7 to 18, unless otherwise specified in this specification. 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.
[0065] Unless otherwise specified in this specification, the substituted or unsubstituted aryl group described in this specification is preferably a phenyl group, a p-biphenyl group, an 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, an m-terphenyl-4-yl group, an m-terphenyl-3-yl group, an 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, or the like.
[0066] Unless otherwise specified in this specification, the substituted or unsubstituted heterocyclic group described in this specification 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 (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 naphthobenzofuranyl group, an azadibenzofuranyl group, a diazadibenzofuranyl group, a dibenzothiophenyl group, a naphthobenzothiophenyl group, an aza Examples of such groups include a dibenzothiophenyl group, a diazadibenzothiophenyl group, a (9-phenyl)carbazolyl group (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, and a phenyldibenzothiophenyl group.
[0067] In this specification, a carbazolyl group is specifically any of the following groups, unless otherwise specified in this specification.
[0068]
[0069] In this specification, unless otherwise specified, the (9-phenyl)carbazolyl group is specifically any of the following groups:
[0070]
[0071] In the general formulae (TEMP-Cz1) to (TEMP-Cz9), * represents a bonding position.
[0072] In this specification, a dibenzofuranyl group and a dibenzothiophenyl group are specifically any of the following groups, unless otherwise specified in this specification.
[0073]
[0074] In the general formulae (TEMP-34) to (TEMP-41), * represents a bonding position.
[0075] Unless otherwise specified herein, the substituted or unsubstituted alkyl groups described herein are preferably methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, and the like.
[0076] "Substituted or unsubstituted arylene group" Unless otherwise specified, the "substituted or unsubstituted arylene group" described in this specification is a divalent group derived by removing one hydrogen atom on the aryl ring from the above-mentioned "substituted or unsubstituted aryl group". Specific examples (specific example group 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 group" described in specific example group G1.
[0077] "Substituted or unsubstituted divalent heterocyclic group" Unless otherwise specified, the "substituted or unsubstituted divalent heterocyclic group" described in this specification is a divalent group derived by removing one hydrogen atom on the heterocycle from the above-mentioned "substituted or unsubstituted heterocyclic group". Specific examples (specific example group G13) of the "substituted or unsubstituted divalent heterocyclic group" include divalent groups derived by removing one hydrogen atom on the heterocycle from the "substituted or unsubstituted heterocyclic group" described in specific example group G2.
[0078] "Substituted or unsubstituted alkylene group" Unless otherwise specified, the "substituted or unsubstituted alkylene group" described in this specification is a divalent group derived by removing one hydrogen atom on the alkyl chain from the above-mentioned "substituted or unsubstituted alkyl group". Specific examples (specific example group 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 group" described in specific example group G3.
[0079] Unless otherwise specified in the present specification, the substituted or unsubstituted arylene group described in the present specification is preferably any one of the groups represented by the following general formulae (TEMP-42) to (TEMP-68).
[0080]
[0081]
[0082] In the general formulae (TEMP-42) to (TEMP-52), Q 1 ~Q 10 are each independently a hydrogen atom or a substituent. In the general formulae (TEMP-42) to (TEMP-52), * represents a bonding position.
[0083]
[0084] In the general formulae (TEMP-53) to (TEMP-62), Q 1 ~Q 10 are each independently a hydrogen atom or a substituent. 9 and Q 10 may be bonded to each other via a single bond to form a ring. In the general formulae (TEMP-53) to (TEMP-62), * represents the bonding position.
[0085]
[0086] In the general formulae (TEMP-63) to (TEMP-68), Q 1 ~Q 8 are each independently a hydrogen atom or a substituent. In the general formulae (TEMP-63) to (TEMP-68), * represents a bonding position.
[0087] Unless otherwise specified in the present specification, the substituted or unsubstituted divalent heterocyclic group described in the present specification is preferably any one of the groups represented by the following general formulae (TEMP-69) to (TEMP-102).
[0088]
[0089]
[0090]
[0091] In the general formulae (TEMP-69) to (TEMP-82), Q 1 ~Q 9 are each independently a hydrogen atom or a substituent.
[0092]
[0093]
[0094]
[0095]
[0096] In the general formulae (TEMP-83) to (TEMP-102), Q 1 ~Q 8 are each independently a hydrogen atom or a substituent.
[0097] The above is the explanation of "substituents described in this specification."
[0098] "When bonded to form a ring" In this specification, when "one or more pairs of adjacent groups bond to each other to form a substituted or unsubstituted monocycle, bond to each other to form a substituted or unsubstituted fused ring, or do not bond to each other," it means when "one or more pairs of adjacent groups bond to each other to form a substituted or unsubstituted monocycle," when "one or more pairs of adjacent groups bond to each other to form a substituted or unsubstituted fused ring," and when "one or more pairs of adjacent groups do not bond to each other." In this specification, the cases when "one or more pairs of adjacent groups bond to each other to form a substituted or unsubstituted monocycle" and "one or more pairs of adjacent groups bond to each other to form a substituted or unsubstituted fused ring" (hereinafter, these cases may be collectively referred to as "when bonded to form a ring") will be explained below. An anthracene compound represented by the following general formula (TEMP-103), in which the main skeleton is an anthracene ring, will be described as an example.
[0099]
[0100] For example, R 921~R 930 In the case where "one or more pairs of adjacent two or more groups are bonded to each other to form a ring," the pair of adjacent two groups is R 921 and R 922 Paired with R 922 and R 923 With the pair, R 923 and R 924 Paired with R 924 and R 930 Paired with R 930 and R 925 Paired with R 925 and R 926 Paired with R 926 and R 927 With the pair, R 927 and R 928 With the pair, R 928 and R 929 and R 929 and R 921 It is paired with.
[0101] The above-mentioned "one or more pairs" means that two or more pairs of adjacent two or more groups may simultaneously form a ring. For example, R 921 and R 922 and are bonded to each other to form ring Q A and simultaneously form R 925 and R 926 and are bonded to each other to form ring Q B When the anthracene compound represented by the general formula (TEMP-103) is formed, the anthracene compound represented by the general formula (TEMP-104) is represented by the following general formula (TEMP-104).
[0102]
[0103] The case where a "set of two or more adjacent groups" forms a ring includes not only the case where a set of "two" adjacent groups is bonded as in the above example, but also the case where a set of "three or more" adjacent groups is bonded. For example, R 921 and R 922 and are bonded to each other to form ring Q A and R 922 and R 923 and are bonded to each other to form ring Q C and three adjacent (R 921 , R 922 and R923 In this case, the anthracene compound represented by the general formula (TEMP-103) is represented by the following general formula (TEMP-105): A and Ring Q C is R 922 Share.
[0104]
[0105] The "monocyclic ring" or "fused ring" formed may be a saturated ring or an unsaturated ring as the structure of only the formed ring. Even when "one pair of adjacent two" forms a "monocyclic ring" or a "fused ring", the "monocyclic ring" or the "fused ring" may form a saturated ring or an unsaturated ring. For example, in the case of the ring Q formed in the general formula (TEMP-104), A and Ring Q B are "monocyclic rings" or "fused rings". A , and ring Q C is a "fused ring". A and Tamaki Q C That is, Ring Q A and Tamaki Q C The ring Q in the general formula (TMEP-104) is fused to form a fused ring. A is a benzene ring, then ring Q A The ring Q in the general formula (TMEP-104) is a monocyclic ring. A is a naphthalene ring, then ring Q A is a fused ring.
[0106] The term "unsaturated ring" means an aromatic hydrocarbon ring or an aromatic heterocyclic ring. The term "saturated ring" means an aliphatic hydrocarbon ring or a non-aromatic heterocyclic ring. Specific examples of aromatic hydrocarbon rings include structures in which the groups given as specific examples in the specific example group G1 are terminated with a hydrogen atom. Specific examples of aromatic heterocyclic rings include structures in which the aromatic heterocyclic groups given as specific examples in the specific example group G2 are terminated with a hydrogen atom. Specific examples of aliphatic hydrocarbon rings include structures in which the groups given as specific examples in the specific example group G6 are terminated with a hydrogen atom. "Forming a ring" means forming a ring only with a plurality of atoms of the main skeleton, or with a plurality of atoms of the main skeleton and one or more optional elements. For example, R 921 and R 922 and a ring Q formed by bonding together A is R 921 and the carbon atom of the anthracene skeleton to which R 922 It means a ring formed by the carbon atom of the anthracene skeleton to which R is bonded and one or more arbitrary elements. 921 and R 922 Todekan Q A In the case where R 921 and the carbon atom of the anthracene skeleton to which R 922 When a monocyclic unsaturated ring is formed by the carbon atom of the anthracene skeleton to which R is bonded and four carbon atoms, R 921 and R 922 The ring formed by
[0107] Here, unless otherwise specified herein, the "arbitrary element" is preferably at least one element selected from the group consisting of carbon, nitrogen, oxygen, and sulfur. In any element (for example, in the case of carbon or nitrogen), a bond that does not form a ring may be terminated with a hydrogen atom or the like, or may be substituted with an "arbitrary substituent" described below. When any element other than a carbon element is included, the formed ring is a heterocycle. Unless otherwise specified herein, the "one or more arbitrary elements" constituting the monocycle or fused ring are preferably 2 to 15, more preferably 3 to 12, and even more preferably 3 to 5. Unless otherwise specified herein, of the "monocycle" and the "fused ring," the "monocycle" is preferred. Unless otherwise specified herein, of the "saturated ring" and the "unsaturated ring," the "unsaturated ring" is preferred. Unless otherwise specified herein, the "monocycle" is preferably a benzene ring. Unless otherwise specified herein, the "unsaturated ring" is preferably a benzene ring. When "one or more pairs of adjacent two or more rings" "combine with each other to form a substituted or unsubstituted monocyclic ring" or "combine with each other to form a substituted or unsubstituted fused ring," unless otherwise specified in this specification, preferably, one or more pairs of adjacent two or more rings combine with each other to form a substituted or unsubstituted "unsaturated ring" consisting of a plurality of atoms of the parent skeleton and at least one element selected from the group consisting of 1 to 15 carbon atoms, nitrogen atoms, oxygen atoms, and sulfur atoms.
[0108] When the above-mentioned "monocyclic ring" or "fused ring" has a substituent, the substituent is, for example, the "optional substituent" described below. When the above-mentioned "monocyclic ring" or "fused ring" has a substituent, specific examples of the substituent are the substituents described in the above section "Substituents Described Herein." When the above-mentioned "saturated ring" or "unsaturated ring" has a substituent, the substituent is, for example, the "optional substituent" described below. When the above-mentioned "monocyclic ring" or "fused ring" has a substituent, specific examples of the substituent are the substituents described in the above section "Substituents Described Herein." The above is an explanation of the case where "one or more pairs of adjacent two or more rings are bonded to form a substituted or unsubstituted monocyclic ring" and the case where "one or more pairs of adjacent two or more rings are bonded to form a substituted or unsubstituted fused ring" ("when bonded to form a ring").
[0109] Substituents in the case of "substituted or unsubstituted" In one embodiment of the present specification, the substituents in the case of "substituted or unsubstituted" (sometimes referred to as "optional substituents" in the present specification) include, for example, an unsubstituted alkyl group having 1 to 50 carbon atoms, an unsubstituted alkenyl group having 2 to 50 carbon atoms, an unsubstituted alkynyl group having 2 to 50 carbon atoms, an unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 ), -O-(R 904 ), -S-(R 905 ), -N(R 906 ) (R 907 ), a halogen atom, a cyano group, a nitro group, an unsubstituted aryl group having 6 to 50 ring carbon atoms, and an unsubstituted heterocyclic group having 5 to 50 ring atoms, 901 ~R 907 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms. 901 When there are two or more R901 are the same or different from each other, R 902 When there are two or more R 902 are the same or different from each other, R 903 When there are two or more R 903 are the same or different from each other, R 904 When there are two or more R 904 are the same or different from each other, R 905 When there are two or more R 905 are the same or different from each other, R 906 When there are two or more R 906 are the same or different from each other, R 907 When there are two or more R 907 are the same or different from each other.
[0110] In one embodiment, the substituent in the "substituted or unsubstituted" is a group selected from the group consisting of an alkyl group having 1 to 50 carbon atoms, an aryl group having 6 to 50 ring carbon atoms, and a heterocyclic group having 5 to 50 ring atoms.
[0111] In one embodiment, the substituent in the "substituted or unsubstituted" is a group selected from the group consisting of an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 ring carbon atoms, and a heterocyclic group having 5 to 18 ring atoms.
[0112] Specific examples of each group of the above optional substituents are the specific examples of the substituents described above in the section "Substituents described in this specification."
[0113] Unless otherwise specified in this specification, adjacent optional substituents may form a "saturated ring" or an "unsaturated ring", preferably 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, more preferably a benzene ring. Unless otherwise specified in this specification, any optional substituent may further have a substituent. The substituents further possessed by the optional substituent are the same as those of the optional substituents described above.
[0114] In this specification, a numerical range expressed using "AA to BB" means a range that includes the number AA written before "AA to BB" as the lower limit and the number BB written after "AA to BB" as the upper limit.
[0115] In this specification, the expression "A≧B" means that the value of A is equal to the value of B, or the value of A is greater than the value of B. In this specification, the expression "A≦B" means that the value of A is equal to the value of B, or the value of A is smaller than the value of B.
[0116] In this specification, the ordinal expressions "first," "second," and "third" are intended to distinguish components and do not imply an order.
[0117] First Embodiment Organic Electroluminescent Element The organic EL element according to the first embodiment includes an organic layer between an anode and a cathode. The organic layer includes at least one layer made of an organic compound. Alternatively, the organic layer includes a stack of multiple layers made of organic compounds. The organic layer may further include an inorganic compound. In the first embodiment, at least one of the organic layers is an emitting layer between the anode and the cathode. The organic layer may, for example, be composed solely of an emitting layer, or may include a layer that can be used in an organic EL element. Layers that can be used in an organic EL element include, but are not limited to, at least one layer selected from the group consisting of a hole injection layer, a hole transport layer, an electron blocking layer, an electron injection layer, an electron transport layer, and a hole blocking layer. In this specification, a region made of multiple organic layers disposed between the anode and the emitting layer may be referred to as a hole transport region. A region made of multiple organic layers disposed between the cathode and the emitting layer may be referred to as an electronic device transport region. In one aspect of the organic EL element according to the first embodiment, a hole transport region is included between the anode and the emitting layer. In one aspect of the organic EL element of the first embodiment, an electron transporting region is included between the cathode and the light-emitting layer.
[0118] The organic EL device according to the first embodiment has an anode, a cathode, and an emitting layer between the anode and the cathode. The emitting layer contains a first compound, a second compound, a third compound, and a fourth compound. The first compound, the second compound, the third compound, and the fourth compound are different from one another. The first compound is a fluorescent compound, and the second compound is a delayed fluorescent compound. The content of the second compound in the emitting layer is 30% by mass or more and 50% by mass or less. The third compound and the fourth compound satisfy the following mathematical formulas (Mathematical Formula 1), (Mathematical Formula 2), and (Mathematical Formula 3). (Mathematical Formula 1): 0.08 eV≦|HOMO(M3)−HOMO(M4)|≦0.22 eV (Mathematical Formula 2): μE(M3)≦5.0×10 -7 cm 2 / Vs (Math 3): μE (M4)≦5.0×10 -7 cm 2 / Vs (HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound, μE(M3) is the electron mobility of the third compound, and μE(M4) is the electron mobility of the fourth compound).
[0119] In conventional organic EL devices, increasing the concentration of the TADF material in the light-emitting layer to a higher concentration (30% by mass or higher) than conventional devices has enabled the device to have a longer life. The present inventors have discovered that an even longer life can be achieved by further incorporating two host materials with different parameters (specifically, two matrix materials that satisfy the relationships of the mathematical formulas (1) to (3)) into an light-emitting layer containing a high concentration of TADF material. This is thought to be because the use of two host materials with different parameters increases the supply of holes to the light-emitting layer and expands the recombination region within the light-emitting layer.
[0120] In the organic EL device according to this embodiment, the third compound and the fourth compound satisfy the following mathematical formula (Mathematical Formula 1), and preferably satisfy the following mathematical formula (Mathematical Formula 11). In the following mathematical formula (Mathematical Formula 1), when |HOMO(M3) - HOMO(M4)| is 0.08 eV or more, a difference in hole supply ability occurs between the two matrix materials, making it easy to adjust the amount of holes supplied in the light-emitting layer. In the following mathematical formula (Mathematical Formula 1), when |HOMO(M3) - HOMO(M4)| is 0.22 eV or less, no excessive difference occurs in the hole supply ability of the two matrix materials, making it easy to adjust the amount of holes supplied in the light-emitting layer. (Mathematical Formula 1): 0.08 eV ≦ |HOMO(M3) - HOMO(M4)| ≦ 0.22 eV (Mathematical Formula 11): 0.08 eV ≦ |HOMO(M3) - HOMO(M4)| ≦ 0.12 eV
[0121] In one aspect of the organic EL element according to this embodiment, the third compound and the fourth compound satisfy the following mathematical formula (14): When the third compound and the fourth compound satisfy the following mathematical formula (14), a difference in hole supply ability occurs between the two matrix materials, making it easy to adjust the amount of holes supplied in the light-emitting layer (Mathematical Formula 14): |HOMO(M4)|>|HOMO(M3)| (HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, and HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound.)
[0122] In one aspect of the organic EL element according to this embodiment, the second compound, the third compound, and the fourth compound satisfy the following mathematical formula (Mathematical Formula 16): |HOMO(M2)|>|HOMO(M4)|>|HOMO(M3)| (HOMO(M2) is the energy level of the highest occupied molecular orbital of the second compound, HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, and HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound.)
[0123] (Method for measuring ionization potential Ip and energy level HOMO of highest occupied molecular orbital) In this specification, the ionization potential and energy level HOMO of the highest occupied molecular orbital of a compound are measured under atmospheric conditions using a photoelectron spectrometer. Specifically, the ionization potential and energy level HOMO of the highest occupied molecular orbital of a compound can be measured by the method described in the examples.
[0124] In one aspect of the organic EL element according to this embodiment, the third compound satisfies the following formula (31) or (32): μE(M3)≦5×10 -8 cm 2 / Vs (Math. 32): μE(M3)≦5×10 -9 cm 2 / Vs (μE(M3) is the electron mobility of the third compound.)
[0125] In one aspect of the organic EL element of this embodiment, μE(M3) is, for example, 1.0×10 -12 cm 2 / Vs or more.
[0126] In one aspect of the organic EL element according to this embodiment, the fourth compound satisfies the following formula (33) or (34): μE(M4)≦5×10 -8 cm 2 / Vs (Math. 34): μE (M4)≦5×10 -9 cm 2 / Vs (μE(M4) is the electron mobility of the fourth compound.)
[0127] In one aspect of the organic EL element of this embodiment, μE(M4) is, for example, 1.0×10 -12 cm 2 / Vs or more.
[0128] (Method for Measuring Electron Mobility) Electron mobility can be measured by performing impedance measurements using a mobility evaluation element fabricated according to the following procedure. The mobility evaluation element is fabricated, for example, according to the following procedure. A compound Target, the electron mobility of which is to be measured, is vapor-deposited on a glass substrate with an aluminum electrode (anode) so as to cover the aluminum electrode, to form a measurement target layer. An electron transport layer is formed on this measurement target layer by vapor-depositing the following compound ET-A. An electron injection layer is formed on this electron transport layer by vapor-depositing LiF. A metal cathode is formed on this electron injection layer by vapor-depositing metallic aluminum (Al). The configuration of the mobility evaluation element described above is schematically shown as follows: Glass / Al(50) / Target(200) / ET-A(10) / LiF(1) / Al(50). Note that the numbers in parentheses indicate film thicknesses (nm).
[0129]
[0130] The electron mobility evaluation element is placed in an impedance measurement device, and impedance measurement is performed. The impedance measurement is performed by sweeping the measurement frequency from 1 Hz to 1 MHz. At this time, a DC voltage V is applied to the element simultaneously with an AC amplitude of 0.1 V. From the measured impedance Z, the modulus M is calculated using the relationship in the following calculation formula (C1). Calculation formula (C1): M = jωZ. In the above calculation formula (C1), j is an imaginary unit whose square is -1, and ω is the angular frequency [rad / s]. In a Bode plot with the imaginary part of the modulus M on the vertical axis and frequency [Hz] on the horizontal axis, the electrical time constant τ of the mobility evaluation element is calculated from the frequency fmax showing the peak using the following calculation formula (C2): Calculation formula (C2): τ = 1 / (2πfmax). π in the above calculation formula (C2) is the symbol representing pi. Using the above τ, the electron mobility μE is calculated from the relationship in the following calculation formula (C3-1). Calculation formula (C3-1): μe=d 2 / (Vτ) In the above formula (C3-1), d is the total film thickness of the organic thin films that constitute the device, and in the case of the device configuration for evaluating the electron mobility, d=210 [nm].
[0131] Fig. 1 shows a schematic configuration of an example of an organic EL element according to the first embodiment. The organic EL element 1 shown in Fig. 1 includes a substrate 2, an anode 3, a cathode 4, and an organic layer 10 disposed between the anode 3 and the cathode 4. The organic layer 10 includes, in order from the anode 3 side, a hole transporting region 7, an emitting layer 5, and an electron transporting region 8. The hole transporting region 7 includes, in order from the anode 3 side, a hole injection layer 74, a hole transporting layer 71, a first electron blocking layer 72, and a second electron blocking layer 73. The electron transporting region 8 includes, in order from the anode 3 side, an electron transporting layer 81 and an electron injection layer 82.
[0132] 2 differs from the organic EL element 1 in that an organic layer 10A includes a hole-transporting region 7A, but is otherwise similar to the organic EL element 1. The hole-transporting region 7A includes, in order from the anode 3 side, a hole-injection layer 74, a hole-transporting layer 71, and a third electron-blocking layer 75. The third electron-blocking layer 75 is composed of a single organic layer.
[0133] The present invention is not limited to the configuration of the organic EL element shown in Figures 1 and 2. Examples of organic EL elements with different configurations include an organic EL element in which the light-emitting layer 5 is made of two organic layers. Also, examples of organic EL elements with different configurations include an organic EL element in which the hole-transport layer 71 is made of two organic layers.
[0134] (Light-emitting layer) In the organic EL element of the first embodiment, the light-emitting layer contains a delayed fluorescent compound as the second compound. Below, an embodiment of the organic EL element of the first embodiment in which the light-emitting layer contains a delayed fluorescent compound (second compound), a first compound (preferably a fluorescent compound), a third compound, and a fourth compound will be described. The first compound, the second compound, the third compound, and the fourth compound are different compounds.
[0135] In the organic EL element of the first embodiment, the first compound is preferably a dopant material (sometimes referred to as a guest material, an emitter, or a light-emitting material), the second compound is preferably a host material (sometimes referred to as a matrix material), the third compound is preferably a host material, and the fourth compound is preferably a host material.
[0136] In the organic EL element of the first embodiment, the first compound, the second compound, the third compound, and the fourth compound are preferably contained in the same layer, that is, the first compound, the second compound, the third compound, and the fourth compound are preferably contained in a single light-emitting layer.
[0137] In the first embodiment, the light-emitting layer preferably does not contain a phosphorescent metal complex, and preferably does not contain any metal complex other than the phosphorescent metal complex. In one embodiment, the light-emitting layer may contain a metal complex. In one embodiment, it is also preferable that the light-emitting layer does not contain a metal complex. In one embodiment, it is preferable that the light-emitting layer does not contain a phosphorescent material. In one embodiment, it is preferable that the light-emitting layer does not contain a heavy metal complex or a phosphorescent rare earth metal complex. Examples of heavy metal complexes include iridium complexes, osmium complexes, and platinum complexes.
[0138] (Second Compound) In the organic EL element according to the first embodiment, the second compound is, for example, a delayed fluorescent compound represented by the following general formula (1).
[0139]
[0140] (In the general formula (1), CN is a cyano group, L is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring carbon atoms, and D 11 and D 12 are each independently a group represented by the following general formula (11), (12) or (13), h is an integer of 2 or more, k is an integer of 1 or more, m is an integer of 0 or more, D 11 and D 12 are the same or different from each other, and a plurality of D 11 are the same or different from each other, and a plurality of D 12 are the same or different from each other.)
[0141]
[0142]
[0143]
[0144] (R in the general formula (11) 1 ~R 8at least one pair of adjacent two or more of R in the general formula (12) is bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or is not bonded to each other, 11 ~R 18 at least one pair of adjacent two or more of R in the general formula (13) are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 111 ~R 118 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and do not form a substituted or unsubstituted monocycle in the general formula (11) and do not form a substituted or unsubstituted fused ring. 1 ~R 8 R in the general formula (12) does not form a substituted or unsubstituted monocyclic ring and does not form a substituted or unsubstituted fused ring. 11 ~R 18 and R in the general formula (13) does not form a substituted or unsubstituted monocyclic ring and does not form a substituted or unsubstituted fused ring. 111 ~R 118 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, in the general formula (12) and the general formula (13), ring A, ring B, and ring C are each independently any ring structure selected from the group consisting of ring structures represented by the following general formulas (14) and (15), ring A, ring B, and ring C are fused to an adjacent ring at any position, p, px, and py are each independently 1, 2, 3, or 4, when p is 2, 3, or 4, multiple rings A are the same or different from each other, when px is 2, 3, or 4, multiple rings B are the same or different from each other, when py is 2, 3, or 4, multiple rings C are the same or different from each other, and * in the general formulas (11) to (13) indicates the bonding position with L in the general formula (1).
[0145]
[0146] (In the general formula (14), r is 0, 2 or 4, and a plurality of R 19 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and in the general formula (15), X 1 is a sulfur atom, an oxygen atom, C(R 151 ) (R 152 ) or N(R 153 ) and R 151 and R 152are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and R 153 R does not form a substituted or unsubstituted monocyclic ring and does not form a substituted or unsubstituted fused ring 151 and R 152 and R which does not form a substituted or unsubstituted monocyclic ring and does not form a substituted or unsubstituted fused ring. 19 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, 19 are the same or different from each other, and a plurality of X 1 are the same or different from each other.)
[0147] In the second compound, R901 ~R 907 and R 931 ~R 937 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R 901 If there are multiple R 901 are the same or different from each other, R 902 If there are multiple R 902 are the same or different from each other, R 903 If there are multiple R 903 are the same or different from each other, R 904 If there are multiple R 904 are the same or different from each other, R 905 If there are multiple R 905 are the same or different from each other, R 906 If there are multiple R 906 are the same or different from each other, R 907 If there are multiple R 907 are the same or different from each other, R 908 If there are multiple R 908 are the same or different from each other, R 909 If there are multiple R 909 are the same or different from each other, R 931 If there are multiple R 931 are the same or different from each other, R 932 If there are multiple R 932 are the same or different from each other, R 933 If there are multiple R 933 are the same or different from each other, R 934 If there are multiple R 934 are the same or different from each other, R 935If there are multiple R 935 are the same or different from each other, R 936 If there are multiple R 936 are the same or different from each other, R 937 If there are multiple R 937 are the same or different from each other.
[0148] In one aspect of the organic EL element according to the first embodiment, at least one D 11 But, R 1 ~R 8 and one or more pairs of adjacent two or more of the following are bonded to each other to form the substituted or unsubstituted monocycle or substituted or unsubstituted fused ring:
[0149] The second compound is also preferably a compound represented by the following general formula (100).
[0150]
[0151] (In the general formula (100), L, D 11 , D 12 , h, k and m are L, D in the general formula (1), respectively. 11 , D 12 , h, k and m are synonymous with each other, and each R independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R908 a group represented by -COOR 909 a cyano group, a nitro group, a group represented by -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, provided that at least one R is a substituent, and at least one R as the substituent is bonded to L of the compound represented by general formula (100) via a carbon-carbon bond, n is an integer of 1 or more, and the multiple Rs are the same or different.
[0152] In the compound represented by the general formula (1) or (100), L is preferably a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 14 ring carbon atoms, and more preferably a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 10 ring carbon atoms. In the compound represented by the general formula (1) or (100), the aromatic hydrocarbon ring having 6 to 14 ring carbon atoms represented by L is preferably a benzene ring, a naphthalene ring, a fluorene ring, or a phenanthrene ring.
[0153] In the compound represented by the general formula (1) or (100), L is preferably a benzene ring. When L is a benzene ring, the compound represented by the general formula (100) is represented by the following general formula (101).
[0154] In the organic EL element according to the first embodiment, the compound (second compound) represented by the general formula (1) is preferably represented by the following general formula (101).
[0155]
[0156] (In the general formula (101), D 11 and D 12 are D in the general formula (1), respectively. 11and D 12 wherein h is 2, 3, 4, or 5, k is 1, 2, 3, or 4, m is 0, 1, 2, or 3, n is 0, 1, 2, or 3, and h+k+m+n=6, and each R is independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a cyano group, a nitro group, a group represented by -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, and the multiple R's are the same or different.
[0157] In the second compound, the benzene ring of the general formula (101) to which the groups represented by the general formulas (11) to (13) are bonded is the benzene ring itself explicitly shown in the general formula (101), and R, D 11 and D 12 It is not a benzene ring contained in
[0158] In the second compound, h is 2, 3, or 4, k is 1, 2, or 3, m is 0, 1, or 2, and n is 1, 2, or 3, provided that at least one R is a substituent, and that at least one R as the substituent is preferably bonded to the benzene ring in general formula (101) via a carbon-carbon bond.
[0159] In the second compound, h is preferably 2 or 3, and more preferably 2.
[0160] In the organic EL device according to the first embodiment, the compound represented by the general formula (1) is preferably a compound represented by the following general formula (110), (120), or (130).
[0161]
[0162] (In the general formulae (110), (120) and (130), D 11 , D 12 , R, k, m and n are each the D in the general formula (1) or (101). 11 , D 12 , R, k, m, and n are synonymous with each other.)
[0163] In the second compound, it is preferred that k is 1, m is 1, and n is 2.
[0164] In the organic EL device according to the first embodiment, the compound represented by the general formula (1) is preferably represented by the following general formula (126) or (127).
[0165]
[0166] (In the general formula (126) and the general formula (127), D 11 is D in the general formula (1). 11 is synonymous with D 12 is D in the general formula (1). 12 is synonymous with R 101 ~R 104 are each independently defined as R in the general formula (1), k is 1 or 2, m is 0 or 1, and k+m is 2.
[0167] In the organic EL device according to the first embodiment, the compound represented by the general formula (1) is also preferably represented by the following general formula (126A), general formula (127A), or general formula (127B).
[0168]
[0169] (In the general formula (126A), the general formula (127A) and the general formula (127B), D 11 represents D in the general formula (1). 11 is synonymous with D 12 represents D in the general formula (1). 12 is synonymous with R 101 ~R 104 are each independently defined as R in the general formula (1).
[0170] In the organic EL device according to the first embodiment, the compound represented by the general formula (1) is a compound represented by the general formula (126A), the general formula (127A), and the general formula (127B) below, 11 and D 12 are preferably different groups.
[0171] In the organic EL device according to the first embodiment, the compound represented by the general formula (1) is also preferably represented by the following general formula (126C) or (127C).
[0172]
[0173] (In the general formula (126C) and the general formula (127C), D 11 represents D in the general formula (1). 11 is synonymous with D 12 represents D in the general formula (1). 12 is synonymous with R 131 ~R 140 and R 141 ~R 150 are each independently defined as R in the general formula (1), k is 1 or 2, m is 0 or 1, and k+m is 2.
[0174] In the organic EL device according to the first embodiment, the compound represented by the general formula (1) is also preferably represented by the following general formula (126D) or (127D).
[0175]
[0176] (In the general formulae (126D) and (127D), D 11 is D in the general formula (1). 11 is synonymous with D 12 is D in the general formula (1). 12 is synonymous with R 131 ~R 140 and R 141 ~R 150 are each independently defined as R in the general formula (1).
[0177] In the second compound, at least one D 11 is preferably a group represented by the general formula (12) or (13).
[0178] In the second compound, at least one D 11 is preferably a group represented by the following general formula (121), (122) or (131).
[0179]
[0180]
[0181]
[0182] (In the general formulas (121) and (122), R 11 ~R 18 are R in the general formula (12), respectively. 11 ~R 18 and ring A is the same as 1、 Ring A 2 , ring A 3 and Ring A 4 Among these, two are ring structures represented by the general formula (14) and the remaining two are ring structures represented by the general formula (15), and in the general formula (131), R 111 ~R 118 are R in the general formula (13), respectively.111 ~R 118 and ring B 1 and Ring B 2 one of the ring structures represented by the general formula (14) is a ring structure represented by the general formula (14), and ring B 1 and Ring B 2 the other is a ring structure represented by the general formula (15), and Ring C 1 and Ring C 2 is a ring structure represented by the general formula (14), and ring C 1 and Ring C 2 the other is a ring structure represented by the general formula (15), and * in the general formulae (121), (122) and (131) indicates the bonding position to L in the general formula (1), or the bonding position to the benzene ring in the general formula (101), (110), (120), (126), (126A), (126C), (126D), (127), (127A), (127B), (127C), (127D) or (130).
[0183] In the second compound, ring A 1 and Ring A 3 is a ring structure represented by the general formula (14), and ring A 2 and Ring A 4 is preferably a ring structure represented by the general formula (15). 1 is a ring structure represented by the general formula (14), and ring B 2 is preferably a ring structure represented by the general formula (15). 1 is a ring structure represented by the general formula (14), and ring C 2 is preferably a ring structure represented by the general formula (15).
[0184] In the second compound, at least one D 11 is preferably a group represented by the general formula (131).
[0185] In the second compound, at least one D 11 is preferably a group represented by the following general formula (123), (124), (125) or (132).
[0186]
[0187]
[0188]
[0189]
[0190] (In the general formulae (123), (124) and (125), R 11 ~R 18 are R in the general formula (12), respectively. 11 ~R 18 is synonymous with R 191 ~R 194 are each independently R in the general formula (14). 19 In the general formula (132), R 111 ~R 118 are R in the general formula (13), respectively. 111 ~R 118 is synonymous with R 195 ~R 198 are each independently R in the general formula (14). 19 In the general formulae (123), (124), (125) and (132), X 13 and X 14 each independently represents X in the general formula (15). 1 and * indicates the bonding position to L in the general formula (1), or the bonding position to the benzene ring in the general formula (101), ((110), (120), (126), (126A), (126C), (126D), (127), (127A), (127B), (127C), (127D) or (130)).
[0191] In the second compound, X 13 is preferably a sulfur atom.
[0192] In the second compound, at least one D 11 is preferably a group represented by the general formula (132).
[0193] In the second compound, m is preferably an integer of 1 or more.
[0194] In the second compound, D 12 is a group represented by the general formula (11) or (12), and m is preferably an integer of 1 or more.
[0195] In the second compound, k and m are preferably 1.
[0196] In the second compound, at least one D 12 is also preferably a group represented by the general formula (11).
[0197] In the second compound, at least one D 12 is also preferably a group represented by the general formula (12).
[0198] In the second compound, the group represented by the general formula (12) is preferably any group selected from the group consisting of groups represented by the following general formulae (12A), (12B), (12C), (12D), (12E), and (12F):
[0199]
[0200]
[0201]
[0202]
[0203]
[0204]
[0205] (In the general formulae (12A), (12B), (12C), (12D), (12E) and (12F), R 11 ~R 18 are R in the general formula (12), respectively. 11 ~R 18 is synonymous with R 19 and R 20 are each independently R in the general formula (14). 19 and X 1 represents X in the general formula (15). 1and * in the general formulae (12A), (12B), (12C), (12D), (12E) and (12F) indicates the bonding position to L in the general formula (1), or the bonding position to the benzene ring in the general formula (101), ((110), (120), (126), (126A), (126C), (126D), (127), (127A), (127B), (127C), (127D) or (130)).
[0206] In the second compound, X 1 is preferably an oxygen atom or a sulfur atom.
[0207] In the second compound, R 1 ~R 8 It is also preferred that adjacent pairs of two or more of R 11 ~R 18 It is also preferred that adjacent pairs of two or more of R 111 ~R 118 It is also preferred that any pair of two or more adjacent groups of the above is not bonded to each other.
[0208] In the second compound, it is preferable that R in the general formula (100) or (101) is each independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms.
[0209] In the second compound, it is preferable that R in the general formula (100) or (101) is each independently a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
[0210] In the second compound, R in the general formula (11) 1 ~R 8 , R in the general formula (12) 11 ~R 18 , R in the general formula (13) 111~R 118 and R in the general formula (14) 19 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms.
[0211] In the second compound, R in the general formula (11) 1 ~R 8 , R in the general formula (12) 11 ~R 18 , R in the general formula (13) 111 ~R 118 and R in the general formula (14) 19 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
[0212] In the second compound, R in the general formula (100) or (101) is each independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, and R in the general formula (11) 1 ~R 8 , R in the general formula (12) 11 ~R 18 , R in the general formula (13) 111 ~R 118 and R in the general formula (14) 19 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms.
[0213] In the second compound, R in the general formula (100) or (101) is each independently a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms, and R in the general formula (11) is 1 ~R 8 , R in the general formula (12) 11 ~R 18 , R in the general formula (13) 111 ~R 118 and R in the general formula (14) 19 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
[0214] In the second compound, the substituent in the term "substituted or unsubstituted" is an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted alkenyl group having 2 to 25 carbon atoms, an unsubstituted alkynyl group having 2 to 25 carbon atoms, an unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 an unsubstituted aralkyl group having 7 to 50 carbon atoms; —C(═O)R 908 a group represented by -COOR 909 a group represented by -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a group represented by —S(═O) 2 R 938a halogen atom, a cyano group, a nitro group, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms, 901 ~R 909 , and R 931 ~R 938 are preferably each independently a hydrogen atom, an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms.
[0215] In the second compound, the substituent in the term "substituted or unsubstituted" is preferably a halogen atom, an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms.
[0216] In the second compound, the substituent in the term "substituted or unsubstituted" is preferably an unsubstituted alkyl group having 1 to 10 carbon atoms, an unsubstituted aryl group having 6 to 12 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 12 ring atoms.
[0217] In the organic EL device according to the first embodiment, it is also preferable that all of the groups described as "substituted or unsubstituted" in the second compound are "unsubstituted" groups.
[0218] In this specification, —O—(R 904 ) is a group represented by R 904 is a hydrogen atom, it is a hydroxy group. 905 ) is a group represented by R 905 is a hydrogen atom, it is a thiol group. 931 ) (R 932 ) is a group represented by R 931 and R 932 is a substituent, it is a substituted phosphine oxide group, and R 931 and R 932 When -Ge(R 933 ) (R 934) (R 935 ) is a group represented by R 933 , R 934 and R 935 is a substituent, it is a substituted germanium group. 936 ) (R 937 ) is a group represented by R 936 and R 937 is a substituent, it is a substituted boryl group.
[0219] (Delayed Fluorescence) Delayed fluorescence is explained on pages 261 to 268 of "Device Properties of Organic Semiconductors" (edited by Adachi Chihaya, published by Kodansha). In this document, the energy difference ΔE between the excited singlet state and the excited triplet state of a fluorescent material is 13 It has been explained that if the transition probability can be reduced, the reverse energy transfer from the excited triplet state to the excited singlet state, which usually has a low transition probability, occurs with high efficiency, resulting in the expression of thermally activated delayed fluorescence (TADF). Furthermore, Figure 10.38 in this document explains the mechanism by which delayed fluorescence occurs. The second compound according to the first embodiment is preferably a compound that exhibits thermally activated delayed fluorescence generated by such a mechanism.
[0220] In general, delayed fluorescence can be confirmed by transient PL (Photoluminescence) measurement.
[0221] The behavior of delayed fluorescence can also be analyzed based on the decay curve obtained from transient PL measurements. Transient PL measurements are a technique in which a sample is excited by irradiating it with a pulsed laser and then measuring the decay behavior (transient characteristics) of PL emission after the irradiation is stopped. PL emission in TADF materials is classified into emission components from singlet excitons generated during the initial PL excitation and emission components from singlet excitons generated via triplet excitons. The lifetime of singlet excitons generated during the initial PL excitation is on the order of nanoseconds, which is very short. Therefore, emission from these singlet excitons decays quickly after irradiation with a pulsed laser. On the other hand, delayed fluorescence decays slowly because it is emission from singlet excitons generated via triplet excitons, which have a long lifetime. Thus, there is a large time difference between emission from singlet excitons generated during the initial PL excitation and emission from singlet excitons generated via triplet excitons. Therefore, the emission intensity derived from delayed fluorescence can be determined.
[0222] A schematic diagram of an exemplary apparatus for measuring transient PL is shown in Figure 3. An example of a method for measuring transient PL and an analysis of the behavior of delayed fluorescence will be described below.
[0223] The transient PL measurement device 100 shown in Fig. 3 includes a pulse laser unit 101 capable of irradiating light of a predetermined wavelength, a sample chamber 102 for accommodating a measurement sample, a spectroscope 103 for dispersing the light emitted from the measurement sample, a streak camera 104 for forming a two-dimensional image, and a personal computer 105 for capturing and analyzing the two-dimensional image. Note that the measurement of transient PL is not limited to the device shown in Fig. 3.
[0224] The sample accommodated in the sample chamber 102 is obtained by forming a thin film on a quartz substrate, in which the doping material is doped at a concentration of 12 mass % relative to the matrix material.
[0225] A pulsed laser is irradiated from the pulsed laser unit 101 onto a thin film sample housed in the sample chamber 102 to excite the doping material. Emission light is extracted in a direction 90 degrees to the irradiation direction of the excitation light, and the extracted light is dispersed by a spectrometer 103, forming a two-dimensional image in a streak camera 104. As a result, a two-dimensional image can be obtained in which the vertical axis corresponds to time, the horizontal axis corresponds to wavelength, and bright spots correspond to emission intensity. Cutting out this two-dimensional image along a predetermined time axis yields an emission spectrum in which the vertical axis represents emission intensity and the horizontal axis represents wavelength. Furthermore, cutting out the two-dimensional image along the wavelength axis yields a decay curve (transient PL) in which the vertical axis represents the logarithm of emission intensity and the horizontal axis represents time.
[0226] For example, a thin film sample A was prepared as described above using the following compound HX1 as the matrix material and the following compound DX1 as the doping material, and transient PL measurement was carried out.
[0227]
[0228] Here, the attenuation curves were analyzed using the above-mentioned thin film sample A and thin film sample B. Thin film sample B was prepared as described above using the following compound HX2 as a matrix material and the above-mentioned compound DX1 as a doping material.
[0229] FIG. 4 shows the decay curves obtained from the transient PL measured for thin film sample A and thin film sample B.
[0230]
[0231] As described above, transient PL measurement can be used to obtain an emission decay curve with the vertical axis representing emission intensity and the horizontal axis representing time. Based on this emission decay curve, the fluorescence intensity ratio between the fluorescence emitted from the singlet excited state generated by photoexcitation and the delayed fluorescence emitted from the singlet excited state generated by reverse energy transfer via the triplet excited state can be estimated. In delayed fluorescent materials, the ratio of the intensity of the delayed fluorescence, which decays slowly, to the intensity of the fluorescence, which decays quickly, is somewhat large.
[0232] Specifically, luminescence from delayed fluorescent materials includes prompt luminescence and delay luminescence. Prompt luminescence is luminescence that is observed immediately from the excited state after being excited by pulsed light (light irradiated from a pulsed laser) having a wavelength that the delayed fluorescent material absorbs. Delay luminescence is luminescence that is not observed immediately after excitation by the pulsed light, but is observed later.
[0233] The amounts of Prompt luminescence and Delay luminescence and their ratio can be determined by a method similar to that described in "Nature 492, 234-238, 2012" (Reference 1). Note that the device used to calculate the amounts of Prompt luminescence and Delay luminescence is not limited to the device described in Reference 1 or the device shown in FIG. 3.
[0234] Furthermore, a sample prepared by the following method is used to measure the delayed fluorescence of the second compound according to the first embodiment. For example, the second compound according to the first embodiment is dissolved in toluene to prepare a dilute solution having an absorbance of 0.05 or less at the excitation wavelength to eliminate the contribution of self-absorption. To prevent quenching by oxygen, the sample solution is frozen and degassed, and then sealed in a lidded cell under an argon atmosphere to obtain an oxygen-free sample solution saturated with argon. The fluorescence spectrum of the sample solution is measured using a spectrofluorometer FP-8600 (manufactured by JASCO Corporation), and the fluorescence spectrum of an ethanol solution of 9,10-diphenylanthracene is also measured under the same conditions. Using the fluorescence area intensities of both spectra, the total fluorescence quantum yield is calculated according to equation (1) in Morris et al. J. Phys. Chem. 80 (1976) 969.
[0235] In the first embodiment, the amount of prompt luminescence (prompt luminescence) of the compound to be measured is calculated as X P The amount of delayed light emission is set to X D When this is done, X D / X PThe measurement of the amounts of prompt luminescence and delay luminescence and their ratio for compounds other than the second compound according to the first embodiment herein is similar to the measurement of the amounts of prompt luminescence and delay luminescence and their ratio for the second compound according to the first embodiment.
[0236] (ΔST) In the first embodiment, the lowest excited singlet energy S 1 and the energy gap T at 77[K] 77K The difference between 1 -T 77K ) is defined as ΔST.
[0237] The lowest excited singlet energy S of the second compound according to the first embodiment 1 (M2) and the energy gap T at 77 [K] of the second compound according to the first embodiment 77K The difference ΔST(M2) between (M2) and ΔST(M2) is preferably less than 0.3 eV, more preferably less than 0.2 eV, even more preferably less than 0.1 eV, and even more preferably less than 0.01 eV. That is, ΔST(M2) preferably satisfies the relationship of the following formula (100), (110), (120), or (130). ΔST(M2)=S 1 (M2)-T 77K (M2)<0.3eV...(several 100) ΔST(M2)=S 1 (M2)-T 77K (M2)<0.2eV...(Math. 110) ΔST(M2)=S 1 (M2)-T 77K (M2)<0.1eV...(Math. 120) ΔST(M2)=S 1 (M2)-T 77K (M2)<0.01eV...(Number 130)
[0238] Relationship Between Triplet Energy and Energy Gap at 77 K: Here, the relationship between triplet energy and energy gap at 77 K will be described. In the first embodiment, the energy gap at 77 K differs from the triplet energy as typically defined. Triplet energy is measured as follows. First, a sample is prepared by dissolving a compound to be measured in an appropriate solvent and sealing the solution in a quartz glass tube. A phosphorescence spectrum (vertical axis: phosphorescence intensity, horizontal axis: wavelength) is measured for this sample at low temperature (77 K). A tangent line is drawn to the rising edge of the short-wavelength side of this phosphorescence spectrum, and the triplet energy is calculated using a predetermined conversion formula based on the wavelength value at the intersection of the tangent line and the horizontal axis. Here, the second compound according to the first embodiment is preferably a thermally activated delayed fluorescence compound with a small ΔST. When ΔST is small, intersystem crossing and reverse intersystem crossing are likely to occur even at low temperatures (77 K), resulting in a mixture of excited singlet and excited triplet states. As a result, the spectrum measured in the same manner as above contains light emission from both the excited singlet state and the excited triplet state, and it is difficult to clearly distinguish which state the light emission is from, but the triplet energy value is considered to be basically dominant. Therefore, in the first embodiment, although the measurement method is the same as that of the normal triplet energy T, in order to distinguish that it is different in the strict sense, the value measured as follows is referred to as the energy gap T 77K The compound to be measured is dissolved in EPA (diethyl ether: isopentane: ethanol = 5:5:2 (volume ratio)) to a concentration of 10 μmol / L, and this solution is placed in a quartz cell to serve as a measurement sample. The phosphorescence spectrum (vertical axis: phosphorescence intensity, horizontal axis: wavelength) of this measurement sample is measured at low temperature (77 [K]), and a tangent line is drawn to the rising edge on the short wavelength side of this phosphorescence spectrum, and the wavelength value λ at the intersection of this tangent line and the horizontal axis is determined. edge Based on the energy gap T at 77 [K], the amount of energy calculated from the following conversion formula (F1) is 77K Conversion formula (F1): T 77K [eV]=1239.85 / λedge
[0239] The tangent to the rising edge of the phosphorescence spectrum on the short wavelength side is drawn as follows: When moving along the spectral curve from the short wavelength side of the phosphorescence spectrum to the shortest maximum among the spectral maxima, consider the tangent at each point on the curve toward the long wavelength side. The slope of this tangent increases as the curve rises (i.e., as the vertical axis increases). The tangent drawn at the point where this slope is at its maximum (i.e., the tangent at the inflection point) is taken as the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side. Note that maximum points with peak intensities of 15% or less of the maximum peak intensity of the spectrum are not included in the shortest wavelength maximum, and the tangent drawn at the point where the slope is closest to the shortest wavelength maximum is taken as the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side. Phosphorescence can be measured using an F-4500 spectrofluorophotometer manufactured by Hitachi High-Technologies Corporation. However, the measuring device is not limited to this, and measurements may be performed by combining a cooling device, a cryogenic container, an excitation light source, and a light receiving device.
[0240] Lowest excited singlet energy S 1 The lowest excited singlet energy S using a solution 1 The following method can be used as a measurement method (sometimes referred to as the solution method): A 10 μmol / L toluene solution of the compound to be measured is prepared and placed in a quartz cell, and the absorption spectrum of this sample (vertical axis: absorption intensity, horizontal axis: wavelength) is measured at room temperature (300 K). A tangent line is drawn to the trailing edge on the long wavelength side of this absorption spectrum, and the wavelength value λedge [nm] at the intersection of this tangent line and the horizontal axis is substituted into the following conversion formula (F2) to calculate the lowest excited singlet energy. Conversion formula (F2): S 1 [eV]=1239.85 / λedge. The absorption spectrum measuring device may be, for example, a spectrophotometer manufactured by Hitachi (device name: U3310), but is not limited to this.
[0241] A tangent to the fall of the absorption spectrum on the long wavelength side is drawn as follows: When moving along the spectral curve from the longest maximum value on the longest wavelength side among the maximum values of the absorption spectrum in the direction of longer wavelengths, consider the tangent at each point on the curve. As the curve falls (i.e., as the value on the vertical axis decreases), the slope of this tangent decreases and then increases repeatedly. The tangent drawn at the point where the slope is minimum on the longest wavelength side (excluding cases where the absorbance is 0.1 or less) is considered to be the tangent to the fall of the absorption spectrum on the long wavelength side. Note that maximum points with absorbance values of 0.2 or less are not included in the maximum value on the longest wavelength side.
[0242] (Method for Producing Second Compound According to First Embodiment) The second compound can be produced by a known method. Alternatively, the second compound can be produced by following a known method and using known alternative reactions and raw materials suited to the target compound.
[0243] (Specific Examples of Second Compound) Specific examples of the second compound according to the first embodiment include the following compounds. However, the present invention is not limited to these specific examples. In this specification, a deuterium atom is represented as D in a chemical formula, and a proton atom is represented as H or is omitted. In this specification, a methyl group may be represented as Me, and a phenyl group may be represented as Ph.
[0244]
[0245]
[0246]
[0247]
[0248]
[0249]
[0250]
[0251]
[0252]
[0253]
[0254]
[0255]
[0256]
[0257]
[0258]
[0259]
[0260]
[0261]
[0262]
[0263] (First Compound) In one aspect of the organic EL element of the first embodiment, the first compound is a fluorescent compound. The first compound is preferably a compound that does not exhibit thermally activated delayed fluorescence. The first compound of the first embodiment is not a phosphorescent metal complex. The first compound is preferably not a heavy metal complex. Furthermore, the first compound is preferably not a metal complex.
[0264] The first compound of the first embodiment can be a fluorescent material. Specific examples of the fluorescent material include bisarylaminonaphthalene derivatives, aryl-substituted naphthalene derivatives, bisarylaminoanthracene derivatives, aryl-substituted anthracene derivatives, bisarylaminopyrene derivatives, aryl-substituted pyrene derivatives, bisarylaminochrysene derivatives, aryl-substituted chrysene derivatives, bisarylaminofluoranthene derivatives, aryl-substituted fluoranthene derivatives, indenoperylene derivatives, acenaphthofluoranthene derivatives, compounds containing boron atoms, pyrromethene-boron complex compounds, compounds having a pyrromethene skeleton, metal complexes of compounds having a pyrromethene skeleton, diketopyrrolopyrrole derivatives, perylene derivatives, and naphthacene derivatives.
[0265] The first compound is preferably a compound that exhibits luminescence with a maximum peak wavelength of 400 nm or more and 700 nm or less. -6 10 moles / liter or more -5 The peak wavelength of the fluorescence spectrum at which the emission intensity is maximum is measured for a toluene solution in which the compound is dissolved at a concentration of 1 / 4 mole / L or less. The measurement device used is a spectrofluorometer (F-7000, manufactured by Hitachi High-Tech Science Corporation).
[0266] The first compound preferably exhibits red or green emission. In this specification, red emission refers to emission having a maximum peak wavelength in the fluorescence spectrum within the range of 600 nm to 660 nm. When the first compound is a red fluorescent compound, the maximum peak wavelength of the first compound is preferably 600 nm to 660 nm, more preferably 600 nm to 640 nm, and even more preferably 610 nm to 630 nm. In this specification, green emission refers to emission having a maximum peak wavelength in the fluorescence spectrum within the range of 500 nm to 560 nm. When the first compound is a green fluorescent compound, the maximum peak wavelength of the first compound is preferably 500 nm to 560 nm, more preferably 500 nm to 540 nm, and even more preferably 510 nm to 540 nm. In this specification, blue emission refers to emission having a maximum peak wavelength in the fluorescence spectrum within the range of 430 nm to 480 nm. When the first compound is a blue fluorescent compound, the maximum peak wavelength of the first compound is preferably 430 nm or more and 480 nm or less, more preferably 440 nm or more and 480 nm or less.
[0267] The first compound is not particularly limited, but is preferably a compound that satisfies the above mathematical formula (Mathematical Formula 21). Examples of the first compound include compounds represented by the following general formulas (D1), (D11), (D10), and (D20). As the first compound, it is preferable to select and use a compound that satisfies the above mathematical formula (Mathematical Formula 21) from the above-mentioned fluorescent material and the compounds represented by the following general formulas (D1), (D11), (D10), and (D20).
[0268] (Compound Represented by General Formula (D1)) In the first embodiment, the first compound is also preferably a compound represented by the following general formula (D1).
[0269]
[0270] (In the general formula (D1), ring Ax, ring Bx, ring Dx, ring Ex, and ring Fx each independently represent a ring structure selected from the group consisting of a substituted or unsubstituted aryl ring having 6 to 30 ring carbon atoms, and a substituted or unsubstituted heterocycle having 5 to 30 ring atoms, one of ring Bx and ring Dx is present, or both ring Bx and ring Dx are present, when both ring Bx and ring Dx are present, ring Bx and ring Dx share a bond connecting Zc and Zh, one of ring Ex and ring Fx is present, or both ring Ex and ring Fx are present, when both ring Ex and ring Fx are present, ring Ex and ring Fx share a bond connecting Zf and Zi, Za is a nitrogen atom or a carbon atom, Zb is, when ring Bx is present, a nitrogen atom or a carbon atom, When the ring Bx does not exist, an oxygen atom, a sulfur atom, NRb, C(Rb 1 ) (Rb 2 ) or Si(Rb 3 ) (Rb 4), Zc is a nitrogen atom or a carbon atom, Zd is a nitrogen atom or a carbon atom when ring Dx is present, and is an oxygen atom, a sulfur atom or NRd when ring Dx is not present, Ze is a nitrogen atom or a carbon atom when ring Ex is present, and is an oxygen atom, a sulfur atom or NRe when ring Ex is not present, Zf is a nitrogen atom or a carbon atom, Zg is a nitrogen atom or a carbon atom when ring Fx is present, and is an oxygen atom, a sulfur atom, NRg, C(Rg 1 ) (Rg 2 ) or Si(Rg 3 ) (Rg 4 ), Zh is a nitrogen atom or a carbon atom, Zi is a nitrogen atom or a carbon atom, Y is a boron atom, a phosphorus atom, SiRh, P=O or P=S, Rb, Rb 1 , Rb 2 , Rb 3 , Rb 4 , Rd, Re, Rg, Rg 1 , Rg 2 , Rg 3 , Rg 4 and Rh are each independently a hydrogen atom or a substituent, and Rb, Rb as a substituent 1 , Rb 2 , Rb 3 , Rb 4 , Rd, Re, Rg, Rg 1 , Rg 2 , Rg 3 , Rg 4 and Rh each independently represent a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, -Si(R 911 ) (R 912 ) (R 913 a group represented by —O—(R 914 ), a group represented by —S—(R 915 ), or a group represented by —N(R 916 ) (R 917) wherein the bond between Y and Za, the bond between Y and Zd, and the bond between Y and Ze are all single bonds. 911 ~R 917 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R 911 If there are multiple R 911 are the same or different from each other, R 912 If there are multiple R 912 are the same or different from each other, R 913 If there are multiple R 913 are the same or different from each other, R 914 If there are multiple R 914 are the same or different from each other, R 915 If there are multiple R 915 are the same or different from each other, R 916 If there are multiple R 916 are the same or different from each other, R 917 If there are multiple R 917 are the same or different from each other.)
[0271] In the first compound, the bond between Y and Za, the bond between Y and Zd, and the bond between Y and Ze are all single bonds, and these single bonds are covalent bonds and not coordinate bonds.
[0272] In this specification, examples of heterocycles include ring structures (heterocycles) obtained by removing a bond from the "heterocyclic group" exemplified in the above-mentioned "substituents described in this specification." These heterocycles may have a substituent or may be unsubstituted. In this specification, examples of aryl rings include ring structures (aryl rings) obtained by removing a bond from the "aryl group" exemplified in the above-mentioned "substituents described in this specification." These aryl rings may have a substituent or may be unsubstituted.
[0273] (Compound Represented by General Formula (D11)) In the organic EL element according to the first embodiment, the first compound is preferably a compound represented by the following general formula (D11): The compound represented by the general formula (D1) is preferably a compound represented by the following general formula (D11):
[0274]
[0275] (In the general formula (D11), ring Ax, ring Dx, and ring Ex each independently represent a ring structure selected from the group consisting of a substituted or unsubstituted aryl ring having 6 to 30 ring carbon atoms, and a substituted or unsubstituted heterocyclic ring having 5 to 30 ring atoms; Za represents a nitrogen atom or a carbon atom; Zb represents an oxygen atom, a sulfur atom, NRb, C(Rb 1 ) (Rb 2 ) or Si(Rb 3 ) (Rb 4 ), Zc is a nitrogen atom or a carbon atom, Zd is a nitrogen atom or a carbon atom, Ze is a nitrogen atom or a carbon atom, Zf is a nitrogen atom or a carbon atom, Zg is an oxygen atom, a sulfur atom, NRg, C(Rg 1 ) (Rg 2 ) or Si(Rg 3 ) (Rg 4 ), Zh is a nitrogen atom or a carbon atom, Zi is a nitrogen atom or a carbon atom, Y is a boron atom, a phosphorus atom, SiRh, P=O or P=S, Rb, Rb 1 , Rb 2 , Rb 3 , Rb 4 , Rg, Rg1 , Rg 2 , Rg 3 , Rg 4 and Rh each independently represent Rb, Rb 1 , Rb 2 , Rb 3 , Rb 4 , Rg, Rg 1 , Rg 2 , Rg 3 , Rg 4 and Rh.)
[0276] (Compound Represented by General Formula (D10)) In the organic EL element according to the first embodiment, the first compound is preferably a compound represented by the following general formula (D10): The compound represented by general formula (D1) is preferably a compound represented by the following general formula (D10):
[0277]
[0278] (In the general formula (D10), X 1 is CR 1 or a nitrogen atom, X 2 is CR 2 or a nitrogen atom, X 3 is CR 3 or a nitrogen atom, X 4 is CR 4 or a nitrogen atom, X 5 is CR 5 or a nitrogen atom, X 6 is CR 6 or a nitrogen atom, X 7 is CR 7 or a nitrogen atom, or X 8 is a carbon atom bonded to X by a single bond; 8 is CR 8 or a nitrogen atom, or X 7 is a carbon atom bonded to X by a single bond; 9 is CR 9 or a nitrogen atom, X 10 is CR 10 or a nitrogen atom, X 11 is CR11 or a nitrogen atom, X 12 is CR 12 or a nitrogen atom, Q is CR Q or a nitrogen atom, and Y is NR Y1 , oxygen atom, sulfur atom, C(R Y2 ) (R Y3 ) or Si(R Y4 ) (R Y5 ) and R 1 ~R 6 and R 9 ~R 11 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 3、 R 4 and R Y1 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 3、 R 4 and R Y1 At least one hydrogen atom in a single ring or a condensed ring formed by bonding together one or more pairs of adjacent groups selected from the group consisting of -O-(R 920 ), and a group represented by —N(R 921 ) (R 922 at least one hydrogen atom in the substituent is substituted with an aryl group having 6 to 50 ring carbon atoms or an alkyl group having 1 to 50 carbon atoms, or is not substituted; R does not form a substituted or unsubstituted monocycle and does not form a substituted or unsubstituted fused ring; 1 ~R 11 , and R 12 ~R 13 , and R Qare each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 911 ) (R 912 ) (R 913 a group represented by —O—(R 914 ), a group represented by —S—(R 915 a group represented by —N(R 916 ) (R 917 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 918 a group represented by -COOR 919 a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, wherein R does not form the substituted or unsubstituted monocycle and does not form the substituted or unsubstituted fused ring. Y1 is a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, and R Y2 and R Y3 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and do not form the substituted or unsubstituted monocycle and do not form the substituted or unsubstituted fused ring. Y2 and R Y3 , and R Y4 and R Y5are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms; R 911 ~R 922 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R 911 If there are multiple R 911 are the same or different from each other, R 912 If there are multiple R 912 are the same or different from each other, R 913 If there are multiple R 913 are the same or different from each other, R 914 If there are multiple R 914 are the same or different from each other, R 915 If there are multiple R 915 are the same or different from each other, R 916 If there are multiple R 916 are the same or different from each other, R 917 If there are multiple R 917 are the same or different from each other, R 918 If there are multiple R 918 are the same or different from each other, R 919 If there are multiple R 919 are the same or different from each other, R 920 If there are multiple R 920 are the same or different from each other, R 921 If there are multiple R 921 are the same or different from each other, R 922 If there are multiple R 922are the same or different from each other.)
[0279] In the compound represented by the general formula (D10), X 7 is X 8 is a carbon atom bonded to X by a single bond, 8 is X 7 and is a carbon atom bonded to by a single bond, for example, general formula (D10) is represented by the following general formula (D10A).
[0280]
[0281] (In the general formula (D10A), X 1 ~X 6 , X 9 ~X 12 , Y, Q, and R 13 are each independently as defined in general formula (D10).
[0282] The compound represented by the general formula (D10) is also preferably represented by the following general formula (D12).
[0283]
[0284] (In the general formula (D12), R 1 ~R 13 , R Y1 , R Q are each independently as defined in general formula (D10).
[0285] The compound represented by the general formula (D10) is also preferably represented by the following general formula (D12A).
[0286]
[0287] (In the general formula (D12A), R 1 ~R 6 , R 9 ~R 13 , R Y1 , R Q are each independently as defined in general formula (D10).
[0288] The compound represented by the general formula (D10) is also preferably represented by the following general formula (D13).
[0289]
[0290] (In the general formula (D13), R 1 ~R 3 , R 5 ~R 13 and R Q are each independently as defined in formula (D10), x1 ~R x4 one or more pairs of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring X1 ~R x4 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, -Si(R 931 ) (R 932 ) (R 933 a group represented by —O—(R 934 ), a group represented by —S—(R 935 a group represented by —N(R 936 ) (R 937 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 938 a group represented by -COOR 939 a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, 931 ~R 939are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R 931 If there are multiple R 931 are the same or different from each other, R 932 If there are multiple R 932 are the same or different from each other, R 933 If there are multiple R 933 are the same or different from each other, R 934 If there are multiple R 934 are the same or different from each other, R 935 If there are multiple R 935 are the same or different from each other, R 936 If there are multiple R 936 are the same or different from each other, R 937 If there are multiple R 937 are the same or different from each other, R 938 If there are multiple R 938 are the same or different from each other, R 939 If there are multiple R 939 are the same or different from each other.)
[0291] In the general formula (D13), for example, R 5 and R 6 are bonded to each other to form a substituted or unsubstituted monocyclic ring, are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other.
[0292] The compound represented by the general formula (D10) is also preferably represented by the following general formula (D13A).
[0293]
[0294] (In the general formula (D13A), R 1 ~R 3 , R 5~R 6 , R 9 ~R 13 and R Q are each independently as defined in general formula (D10), and R x1 ~R x4 are each independently as defined in general formula (D13).
[0295] In the compound represented by the general formula (D10), R 1 ~R 13 and R Q are also preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 50 ring atoms.
[0296] In the compound represented by the general formula (D10), R 1 ~R 13 and R Q are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms, a substituted or unsubstituted aryl group having 6 to 25 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 25 ring atoms.
[0297] In the compound represented by the general formula (D10), R 1 ~R 3 , R 5 ~R 13 , R Q and R x1 ~R x4 are also preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 50 ring atoms.
[0298] In the compound represented by the general formula (D10), R 1 ~R 3 , R 5 ~R 13 , R Q and Rx1 ~R x4 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms, a substituted or unsubstituted aryl group having 6 to 25 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 25 ring atoms.
[0299] In the compound represented by the general formula (D10), R 1 ~R 13 , R Q and R x1 ~R x4 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 50 ring atoms.
[0300] In the compound represented by the general formula (D10), R 1 ~R 13 , R Q and R x1 ~R x4 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 25 carbon atoms, a substituted or unsubstituted aryl group having 6 to 25 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 25 ring atoms.
[0301] The compound represented by the general formula (D10) is also preferably represented by the following general formula (D14).
[0302]
[0303] (In the general formula (D14), R 2 , R 6、 R 13、 R Q and R x2 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 12 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 18 ring atoms.
[0304] The compound represented by the general formula (D10) is also preferably represented by the following general formula (D15).
[0305]
[0306] (In the general formula (D15), R 2 , R 6、 R 13、 R Q and R x2 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 12 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 18 ring atoms.
[0307] In the compound represented by the general formula (D10), R 13 and R Q are preferably each independently a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, or a substituted or unsubstituted dibenzofuranyl group.
[0308] In the compound represented by the general formula (D10), R 6 and R x2 are preferably each independently a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms.
[0309] (Compound Represented by General Formula (D20)) In the organic EL element according to the first embodiment, the first compound is also preferably a compound represented by the following general formula (D20).
[0310]
[0311] In the general formula (D20), X is a nitrogen atom or a carbon atom bonded to Y, Y is a hydrogen atom or a substituent, and R 21 ~R 26 are each independently a hydrogen atom or a substituent, or R 21 and R 22 Group R 22 and R23 Group R 24 and R 25 and R 25 and R 26 any one or more pairs of Y and R are bonded to each other to form a ring; 21 ~R 26 are each independently a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted arylthio group having 6 to 30 ring carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a halogen atom, a carboxy group, a substituted or unsubstituted ester group, is selected from the group consisting of a substituted or unsubstituted carbamoyl group, a substituted or unsubstituted amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, and a substituted or unsubstituted siloxanyl group; 21 and Z 22 are each independently a substituent, or Z 21 and Z 22 are bonded to each other to form a ring, and Z as a substituent 21 and Z 22are each independently selected from the group consisting of a halogen atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkoxy group having 1 to 30 carbon atoms, and a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms.
[0312] In the first compound according to the first embodiment, the substituent in the term "substituted or unsubstituted" is an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted alkenyl group having 2 to 25 carbon atoms, an unsubstituted alkynyl group having 2 to 25 carbon atoms, an unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 an unsubstituted aralkyl group having 7 to 50 carbon atoms; —C(═O)R 908 a group represented by -COOR 909 a group represented by -S(=O) 2 R 941 a group represented by -P(=O)(R 942 ) (R 943 a group represented by —Ge(R 944 ) (R 945 ) (R 946 ), a halogen atom, a cyano group, a nitro group, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms, 901 ~R 909 , and R 941 ~R 946are preferably each independently a hydrogen atom, an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms.
[0313] In the first compound according to the first embodiment, the substituent in the case of being “substituted or unsubstituted” is preferably a halogen atom, an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms.
[0314] In the first compound according to the first embodiment, the substituent in the case of being “substituted or unsubstituted” is preferably an unsubstituted alkyl group having 1 to 10 carbon atoms, an unsubstituted aryl group having 6 to 12 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 12 ring atoms.
[0315] In the first compound according to the first embodiment, it is also preferable that all groups described as "substituted or unsubstituted" are "unsubstituted" groups.
[0316] (Specific examples of compounds represented by general formula (D1), (D11), (D10) or (D20)) Specific examples of the compounds represented by general formula (D1), (D11), (D10) or (D20) include the following compounds. However, the present invention is not limited to these specific examples.
[0317]
[0318]
[0319] (Third Compound and Fourth Compound) In one aspect of the organic EL element according to the first embodiment, the third compound may be a thermally activated delayed fluorescent compound or a compound that does not exhibit thermally activated delayed fluorescence, but is preferably a compound that does not exhibit thermally activated delayed fluorescence. The third compound is not particularly limited as long as it satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 2), but is preferably a compound that satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 2) and is represented by the following general formula (3) or a compound that is represented by the following general formula (MRX3). As the third compound, it is preferable to select and use a compound that satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 2) from among the compounds represented by the following general formula (3) and the compounds represented by the following general formula (MRX3). In one aspect of the organic EL element according to the first embodiment, the fourth compound may be a thermally activated delayed fluorescent compound or a compound that does not exhibit thermally activated delayed fluorescence, but is preferably a compound that does not exhibit thermally activated delayed fluorescence. The fourth compound is not particularly limited as long as it satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 3), but is preferably a compound that satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 3) and is represented by the following general formula (3), or a compound that is represented by the following general formula (MRX3). As the fourth compound, it is preferable to select and use a compound that satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 3) from the compounds that are represented by the following general formula (MRX3).
[0320] (Compound represented by general formula (3))
[0321]
[0322] (In the general formula (3), A 3 is a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, L 3is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, a divalent group formed by bonding together two groups selected from the group consisting of a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms and a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, or a divalent group formed by bonding together three groups selected from the group consisting of a substituted or unsubstituted arylene group having 6 to 30 ring carbon atoms and a substituted or unsubstituted divalent heterocyclic group having 5 to 30 ring atoms, R 31 ~R 38 one or more pairs of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring 31 ~R 38 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935), a group represented by —B(R 936 ) (R 937 ) a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the following general formula (3A):
[0323]
[0324] (In the general formula (3A), R B represents a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, B When there are multiple R B are the same or different from each other, and L 31is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, a trivalent group, a tetravalent group, a pentavalent group, or a hexavalent group derived from the arylene group, a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, a trivalent group, a tetravalent group, a pentavalent group, or a hexavalent group derived from the heterocyclic group, or a divalent group formed by bonding two groups selected from the group consisting of substituted or unsubstituted arylene groups having 6 to 50 ring carbon atoms and substituted or unsubstituted divalent heterocyclic groups having 5 to 50 ring atoms, or a trivalent group, a tetravalent group, a pentavalent group, or a hexavalent group derived from the divalent group, 32 represents a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, 3 is 1, 2, 3, 4 or 5, and L 31 When is a single bond, n 3 is 1, and L 32 is bonded to a carbon atom of the six-membered ring in the general formula (3), and L 32 When there are multiple L 32 are the same or different, and * is the bonding site to the carbon atom of the six-membered ring in the general formula (3).
[0325] (In the compound represented by the general formula (3), R 901 , R 902 , R 903 , R 904 , R 905 , R 906 , R 907 , R 908 , R 909 , R 931 , R 932 , R 933 , R 934 , R 935 , R 936 and R 937are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R 901 If there are multiple R 901 are the same or different from each other, R 902 If there are multiple R 902 are the same or different from each other, R 903 If there are multiple R 903 are the same or different from each other, R 904 If there are multiple R 904 are the same or different from each other, R 905 If there are multiple R 905 are the same or different from each other, R 906 If there are multiple R 906 are the same or different from each other, R 907 If there are multiple R 907 are the same or different from each other, R 908 If there are multiple R 908 are the same or different from each other, R 909 If there are multiple R 909 are the same or different from each other, R 931 If there are multiple R 931 are the same or different from each other, R 932 If there are multiple R 932 are the same or different from each other, R 933 If there are multiple R 933 are the same or different from each other, R 934 If there are multiple R 934 are the same or different from each other, R 935 If there are multiple R 935 are the same or different from each other, R 936If there are multiple R 936 are the same or different from each other, R 937 If there are multiple R 937 are the same or different from each other.)
[0326] The compound represented by the general formula (3) is also preferably a compound represented by any one of the following general formulae (31) to (36).
[0327]
[0328]
[0329]
[0330] (In the general formulae (31) to (36), A 3 and L 3 are the same as A in the general formula (3), respectively. 3 and L 3 is synonymous with R 341 ~R 350 one or more pairs of adjacent two or more of X are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 31 represents a sulfur atom, an oxygen atom, and NR 352 or CR 353 R 354 and R 353 and R 354 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and do not form the substituted or unsubstituted monocycle and do not form the substituted or unsubstituted fused ring. 341 ~R 350 And, R 352 and R which does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 353 and R 354 and R each independently represent a group that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 31~R 38 is synonymous with
[0331] In the compound represented by the general formula (3), R 352 is preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0332] In the compound represented by the general formula (3), R 353 and R 354 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other to form a substituted or unsubstituted monocycle and a substituted or unsubstituted fused ring 353 and R 354 are preferably each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0333] In the compound represented by the general formula (3), X 31 is preferably a sulfur atom or an oxygen atom.
[0334] In the compound represented by the general formula (3), A 3 is preferably a group represented by any one of the following general formulae (A31) to (A37).
[0335]
[0336]
[0337] (In the general formulae (A31) to (A37), a plurality of R 300one or more pairs of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring 300 , and R 333 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 * in the general formulae (A31) to (A37) respectively represents L of the compound represented by the general formula (3). 3 indicates the bonding position with
[0338] In the compound represented by the general formula (3), A 3 is also preferably a group represented by the general formula (A34), (A35) or (A37).
[0339] In the compound represented by the general formula (3), A 3 is preferably a group represented by any one of the following general formulae (A371) to (A376).
[0340]
[0341]
[0342]
[0343] (In the general formulae (A371) to (A376), Y 3 is a sulfur atom, an oxygen atom, N(R 381 ) or C(R 382 ) (R 383 ) and R 382 and R 383 are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and R 371 ~R 380one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 381 R does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring 371 ~R 380 and R which does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 382 and R 383 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 * in the general formulae (A371) to (A376) represents L of the compound represented by the general formula (3), respectively. 3 indicates the bonding position with
[0344] In the general formulae (A371) to (A376), R 381 is preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0345] In the general formulae (A371) to (A376), R 382 and R 383 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other to form a substituted or unsubstituted monocycle and a substituted or unsubstituted fused ring 382 and R 383 are preferably each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0346] In the general formulae (A371) to (A376), Y 3is preferably a sulfur atom or an oxygen atom.
[0347] The compound represented by the general formula (3) is also preferably a compound represented by any one of the following general formulae (311) to (316).
[0348]
[0349]
[0350]
[0351]
[0352]
[0353]
[0354] (In the general formulae (311) to (316), L 3 represents L in the general formula (3). 3 and plural R 300 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 341 ~R 350 one or more pairs of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring 300 and R which does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 341 ~R 350 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 is synonymous with
[0355] The compound represented by the general formula (3) is also preferably a compound represented by any one of the following general formulae (311A) to (316A).
[0356]
[0357]
[0358] (In the general formulae (311A) to (316A), L 3 , R 300 and R 341 ~R 350 respectively represent L in the general formulae (311) to (316). 3 , R 300 and R 341 ~R 350 is synonymous with
[0359] The compound represented by the general formula (3) is also preferably a compound represented by any one of the following general formulae (321A) to (326A).
[0360]
[0361]
[0362]
[0363] (In the general formulae (321A) to (326A), L 3 represents L in the general formula (3). 3 is synonymous with R 341 ~R 350 one or more pairs of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring 341 ~R 350 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 is synonymous with R 371 ~R 380respectively represent R in the general formulae (A371) to (A376). 371 ~R 380 is synonymous with
[0364] In the general formulae (311A) to (316A) and (321A) to (326A), L 3 is preferably a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, or a substituted or unsubstituted terphenylene group, and more preferably an unsubstituted phenylene group, an unsubstituted biphenylene group, or an unsubstituted terphenylene group.
[0365] The compound represented by the general formula (3) is also preferably a compound represented by the following general formula (321).
[0366]
[0367] (In the general formula (321), L 3 represents L in the general formula (3). 3 is synonymous with R 31 ~R 38 , and R 301 ~R 308 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 is synonymous with
[0368] In the compound represented by the general formula (3), L 3 is preferably a single bond or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms.
[0369] In the compound represented by the general formula (3), L 3 is preferably a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, or a substituted or unsubstituted terphenylene group.
[0370] In the compound represented by the general formula (3), L 3 is preferably a group represented by the following general formula (317).
[0371]
[0372] (In the general formula (317), R 310 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 and * each independently indicates a bonding position.)
[0373] In the compound represented by the general formula (3), L 3 It is also preferable that L contains a divalent group represented by the following general formula (318) or general formula (319). 3 is also preferably a divalent group represented by the following general formula (318) or general formula (319).
[0374] The compound represented by the general formula (3) is also preferably a compound represented by the following general formula (322) or (323).
[0375]
[0376]
[0377] (In the general formula (322) and the general formula (323), L 31 represents a divalent group formed by bonding two groups selected from the group consisting of a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms and a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, with the proviso that L 31 R contains a divalent group represented by the following general formula (318) or general formula (319): 31 ~R 38 , R 300 , and R 321 ~R 328 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 is synonymous with
[0378]
[0379] (In the general formula (319), a plurality of R 304 a pair of adjacent two of these is bonded to each other to form a ring represented by the general formula (320), and in the general formula (320), 1* and 2* each independently represent R 304 represents the bonding position with the ring to which R is bonded, 302 , R in the general formula (319) 303 R which does not form a ring represented by the general formula (320) 304 and R in the general formula (320) 305 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 In the general formulae (318) to (320), * indicates the bonding position.
[0380] In the compound represented by the general formula (3), L 3 or L 31 The group represented by the general formula (319) as is, for example, a group represented by the following general formula (319A).
[0381]
[0382] (In the general formula (319A), R 303 , R 304 and R 305 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 and * in the general formula (319A) indicates a bonding position.)
[0383] The compound represented by the general formula (3) is a compound represented by the general formula (322), and L 31 is also preferably a group represented by the general formula (318).
[0384] The compound represented by the general formula (3) is also preferably a compound represented by the following general formula (324).
[0385]
[0386] (In the general formula (324), R 31 ~R 38 , R 300 , and R 302 each independently represents R that does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring; 31 ~R 38 is synonymous with
[0387] In the compound represented by the general formula (3), R does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 31 ~R 38 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the general formula (3A), and R in the general formula (3A) B is preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0388] In the compound represented by the general formula (3), R does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 31 ~R 38 are each independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a group represented by the general formula (3A), and R B is preferably a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms.
[0389] In the compound represented by the general formula (3), R does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 31 ~R38 are each independently a hydrogen atom, a substituted or unsubstituted phenyl group, or a group represented by the general formula (3A), and R B is preferably a substituted or unsubstituted phenyl group.
[0390] The compound represented by the general formula (3) is also preferably a compound having no pyridine ring, no pyrimidine ring, and no triazine ring.
[0391] (Compound Represented by General Formula (3B)) In the organic EL element according to the first embodiment, it is also preferable to select as the third compound a compound represented by the following general formula (3B) that satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 2). It is also preferable to select as the fourth compound a compound represented by the following general formula (3B) that satisfies the above mathematical formulas (Mathematical Formula 1) and (Mathematical Formula 3). The compound represented by the following general formula (3B) is one embodiment of the compound represented by the general formula (3).
[0392]
[0393] In the general formula (3B), X B is an oxygen atom or a sulfur atom, 1 is a carbon atom, n is 1, 2, or 3, k is 1, 2, or 3, m is 2, 3, or 4, and k+m=5, and when m is 2 or more, a plurality of R L are the same or different from each other, R B1 ~R B8 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocycle, bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and when at least one of n and k is 2 or more, a plurality of R B1 are the same or different, and a plurality of R B2 are the same or different, and a plurality of R B3 are the same or different, and a plurality of R B4 are the same or different, and a plurality of R B5are the same or different, and a plurality of R B6 are the same or different, and a plurality of R B7 are the same or different, and a plurality of R B8 are the same or different from each other, L B1 is a single bond or a linking group, provided that L B1 is a single bond, n is 1, and when k is 2 or more, a plurality of L B1 are the same or different from each other, and L as a linking group B1 represents a group derived from a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a group derived from a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, or a group formed by bonding two groups selected from the group consisting of a group derived from a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms and a group derived from a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, and when k is 1 and m is 4, four R L are each bonded to a carbon atom at any of the positions a, b, c, d, and e shown in the general formula (3B), and one L B1 is the R L When k is 2 and m is 3, the carbon atom at the position a, b, c, d, or e is bonded to the carbon atom at which the carbon atom at the position a is not bonded to the carbon atom at which the carbon atom at the position a is bonded to the carbon atom at which the carbon atom at the position L are bonded to any of the carbon atoms at positions a, b, c, d, and e shown in the general formula (3B), and two L B1 are the R L When k is 3 and m is 2, the carbon atom bonded to any of the carbon atoms at positions a, b, c, d, and e that are not bonded to two R L are bonded to any of the carbon atoms at positions a, b, c, d, and e shown in the general formula (3B), and three L B1 are the R L and R is bonded to any of the carbon atoms at positions a, b, c, d, and e that are not bonded to R B40 and R B45 ~R B48one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, provided that three R B40 are the same or different from each other, and three R B40 are bonded to any of the carbon atoms at positions f, g, h, and i in the general formula (3B), and C 1 is the R B40 bonded to any of carbon atoms at positions f, g, h, and i that are not bonded to R L , R B31 , R B32 , R B34 , R B35 R does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring B1 ~R B8 and R which does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. B40 and R B45 ~R B48 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, -P(=O)(R 931 ) (R 932 a group represented by —Ge(R933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0394] In the compound represented by the general formula (3B), when n is 2 or 3, the nitrogen atom N* in the structure in parentheses enclosed by the subscript n is, respectively, L B1 In the compound represented by the general formula (3B), L B1 is a single bond, the nitrogen atom N* in the structure in the parentheses enclosed by the subscript n is bonded to any of the carbon atoms at the positions a, b, c, d, and e. In the compound represented by the general formula (3B), when k is 2 or 3, L in the structure in the parentheses enclosed by the subscript k is bonded to any of the carbon atoms at the positions a, b, c, d, and e. B1 are bonded to any of the carbon atoms at positions a, b, c, d, and e, respectively.
[0395] For example, in the compound represented by the general formula (3B), n is 2, k is 1, and L B1 is bonded to the carbon atom at position c, and carbon atom C 1 is bonded to the carbon atom at position h, the compound represented by general formula (3B) is represented by the following general formula (31B).
[0396]
[0397] (In the general formula (31B), R B1 ~R B8 , R L , R B31 , R B32 , R B34 , R B35 , R B40 , R B45 ~R B48 , L B1 and X B are as defined in the general formula (3B).
[0398] For example, in the compound represented by the general formula (3B), L B1is a single bond, n is 2, one of the two nitrogen atoms N* in the structure in parentheses enclosed by the subscript n is bonded to the carbon atom at position b, and the other is bonded to the carbon atom at position b, and the carbon atom C 1 When is bonded to the carbon atom at position h, the compound represented by general formula (3B) is represented by the following general formula (32B).
[0399]
[0400] (In the general formula (32B), R B1 ~R B8 , R L , R B31 , R B32 , R B34 , R B35 , R B40 , R B45 ~R B48 , and X B are as defined in the general formula (3B).
[0401] (Compound represented by general formula (MRX3))
[0402]
[0403] (In the general formula (MRX3), Y 31 ~Y 36 are each independently CR 3 or a nitrogen atom, provided that Y 31 ~Y 36 two or more of R are nitrogen atoms; 3 If there are multiple R 3 one or more pairs of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring 3are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 ) a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by the following general formula (MRX3A):
[0404]
[0405] (In the general formula (MRX3A), R B is R in the general formula (3). B is synonymous with R B When there are multiple R B are the same or different from each other, and L 31 and L 32 respectively represent L in the general formula (3). 31 and L 32 is synonymous with n 3 is 1, 2, 3, 4 or 5, and L31 When is a single bond, n 3 is 1, and L 32 is bonded to a carbon atom of the six-membered ring in general formula (MRX3), 32 When there are multiple L 32 are the same or different, and * represents the bonding site to the carbon atom of the six-membered ring in general formula (MRX3).
[0406] The compound represented by the general formula (MRX3) preferably does not contain a pyridine ring in the molecule.
[0407] The compound represented by the general formula (MRX3) is also preferably a compound represented by the following general formula (MRX31) or (MRX32).
[0408]
[0409] (In the general formula (MRX32), R 35 ~R 37 one or more pairs of adjacent two or more of R in the general formula (MRX31) are bonded to each other to form a substituted or unsubstituted monocycle, bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 31 ~R 33 and R in the general formula (MRX32) 34 and R which does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 35 ~R 37 each independently represents R in general formula (MRX3). 3 is synonymous with
[0410] The compound represented by the general formula (MRX3) is also preferably a compound represented by the general formula (MRX31).
[0411] R in the general formula (MRX3) 3are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, or a group represented by general formula (MRX3A).
[0412] R in the general formula (MRX3) 3 are preferably each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a group represented by general formula (MRX3A) above.
[0413] The compound represented by the general formula (MRX3) preferably has, in the molecule, at least one group selected from the group consisting of groups represented by the following general formulae (MRXA31) to (MRXA44).
[0414]
[0415]
[0416] (In the general formulae (MRXA31) to (MRXA38), a plurality of R 300 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 331 and R 332 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and do not form the substituted or unsubstituted monocycle and do not form the substituted or unsubstituted fused ring. 300 , R 331 and R 332 , and R 333are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, and * in the general formulae (MRXA31) to (MRXA38) respectively indicates the bonding position to other atoms in the molecule of the compound represented by the general formula (MRX3).
[0417]
[0418]
[0419]
[0420] (In the general formulae (MRXA39) to (MRXA44), R 341 ~R 350 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, with the proviso that R 341 ~R 351 at least one of the following represents a bonding position to another atom in the molecule of the compound represented by general formula (MRX3); 31 represents a sulfur atom, an oxygen atom, and NR352 or CR 353 R 354 and R 353 and R 354 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and are not at a bonding position with another atom in the molecule of the compound represented by general formula (MRX3), and do not form the substituted or unsubstituted monocycle and do not form the substituted or unsubstituted fused ring. 341 ~R 351 And, R 352 and R which does not form the substituted or unsubstituted monocyclic ring and does not form the substituted or unsubstituted fused ring. 353 and R 354 and each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, —C(═O)R 908 a group represented by -COOR 909 a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0421] The compound represented by the general formula (MRX3) preferably has at least one group selected from the group consisting of the groups represented by the general formulae (MRXA38) to (MRXA44) in the molecule.
[0422] In the compound represented by the general formula (MRX3), Y 31 ~Y 36 At least one of the following is CR 3 and at least one R 3 is a group represented by the general formula (MRX3A), and R B is preferably any one of the groups represented by the general formulae (MRXA31) to (MRXA44).
[0423] In the compound represented by the general formula (MRX3), Y 31 ~Y 36 At least one of the following is CR 3 and at least one R 3 is a group represented by the general formula (MRX3A), and R B is preferably any one of the groups represented by the general formulae (MRXA38) to (MRXA44).
[0424] In the compound represented by the general formula (MRX3), R 352 is preferably a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0425] In the compound represented by the general formula (MRX3), R 353 and R 354 are bonded to each other to form a substituted or unsubstituted monocycle, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other to form a substituted or unsubstituted monocycle and a substituted or unsubstituted fused ring 353 and R 354 are preferably each independently a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms.
[0426] In the compound represented by the general formula (3) and the compound represented by the general formula (MRX3), L 31is a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, a trivalent group, a tetravalent group, a pentavalent group or a hexavalent group derived from the arylene group, or a divalent group formed by bonding two groups selected from the group consisting of substituted or unsubstituted arylene groups having 6 to 50 ring carbon atoms, or a trivalent group, a tetravalent group, a pentavalent group or a hexavalent group derived from the divalent group, 32 is preferably a single bond or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms.
[0427] In the compound represented by the general formula (3) and the compound represented by the general formula (MRX3), L 31 represents a single bond or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, and n 3 is 1, and L 32 is preferably a single bond or a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms.
[0428] In the compound represented by the general formula (3) and the compound represented by the general formula (MRX3), L 31 represents a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, a divalent group formed by bonding two groups selected from the group consisting of a substituted or unsubstituted phenylene group and a substituted or unsubstituted biphenylene group, or a trivalent group, tetravalent group, pentavalent group or hexavalent group derived from the divalent group; 3 is 1, and L 32 is preferably a single bond, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted biphenylene group.
[0429] In the compound represented by the general formula (3), the compound represented by the formula (3B), and the compound represented by the general formula (MRX3), the substituent in the term "substituted or unsubstituted" is an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted alkenyl group having 2 to 25 carbon atoms, an unsubstituted alkynyl group having 2 to 25 carbon atoms, an unsubstituted cycloalkyl group having 3 to 25 ring carbon atoms, -Si(R901 ) (R 902 ) (R 903 a group represented by —O—(R 904 ), a group represented by —S—(R 905 a group represented by —N(R 906 ) (R 907 an unsubstituted aralkyl group having 7 to 50 carbon atoms; —C(═O)R 908 a group represented by -COOR 909 a group represented by -P(=O)(R 931 ) (R 932 a group represented by —Ge(R 933 ) (R 934 ) (R 935 ), a group represented by —B(R 936 ) (R 937 a group represented by —S(═O) 2 R 938 a halogen atom, a cyano group, a nitro group, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms, 901 ~R 909 , and R 931 ~R 938 are preferably each independently a hydrogen atom, an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms.
[0430] In the compounds represented by the general formula (3), the compounds represented by the formula (3B), and the compounds represented by the general formula (MRX3), the substituent in the case of "substituted or unsubstituted" is preferably a halogen atom, an unsubstituted alkyl group having 1 to 25 carbon atoms, an unsubstituted aryl group having 6 to 25 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 25 ring atoms.
[0431] In the compounds represented by the general formula (3), the compounds represented by the formula (3B), and the compounds represented by the general formula (MRX3), the substituent in the case of "substituted or unsubstituted" is preferably an unsubstituted alkyl group having 1 to 10 carbon atoms, an unsubstituted aryl group having 6 to 12 ring carbon atoms, or an unsubstituted heterocyclic group having 5 to 12 ring atoms.
[0432] In the compound represented by the general formula (3), the compound represented by the formula (3B), and the compound represented by the general formula (MRX3), it is also preferable that the groups described as "substituted or unsubstituted" are all "unsubstituted" groups.
[0433] The compound represented by the general formula (3), the compound represented by the formula (3B), and the compound represented by the general formula (MRX3) can be produced by known methods.
[0434] Specific examples of the compound represented by the general formula (3), the compound represented by the formula (3B), and the compound represented by the general formula (MRX3) include the following compounds, although the present invention is not limited to these specific examples of compounds.
[0435]
[0436]
[0437]
[0438]
[0439]
[0440]
[0441]
[0442]
[0443]
[0444]
[0445]
[0446]
[0447]
[0448]
[0449]
[0450]
[0451]
[0452] (Relationship Between First Compound, Second Compound, Third Compound, and Fourth Compound in Emitting Layer) In the organic EL element according to the first embodiment, the first compound and the second compound preferably satisfy the following mathematical formula (Mathematical Formula 4): (Mathematical Formula 4): S 1 (M2) > S 1 (M1) (S 1 (M1) is the lowest excited singlet energy of the first compound, and S 1 (M2) is the lowest excited singlet energy of the second compound.
[0453] In the organic EL element according to the first embodiment, the second compound and the third compound preferably satisfy the following formula (Formula 5): (Formula 5): S 1 (M3) > S 1 (M2) (S 1 (M2) is the lowest excited singlet energy of the second compound, and S 1 (M3) is the lowest excited singlet energy of the third compound.
[0454] In the organic EL element according to the first embodiment, the second compound and the fourth compound preferably satisfy the following formula (Formula 6): (Formula 6): S 1 (M4) > S 1 (M2) (S 1 (M2) is the lowest excited singlet energy of the second compound, and S 1 (M4) is the lowest excited singlet energy of the fourth compound.
[0455] In the organic EL device according to the first embodiment, the lowest excited singlet energy S 1(M1) and the lowest excited singlet energy S of the second compound 1 (M2) and the lowest excited singlet energy S of the third compound 1 (M3) preferably satisfy the relationship of the following mathematical formula (Mathematical Formula 3A): 1 (M3) > S 1 (M2) > S 1 (M1) ...(Math 3A)
[0456] The energy gap T at 77 [K] of the third compound 77K (M3) is the energy gap T at 77 [K] of the second compound 77K The energy gap T at 77 [K] of the third compound is preferably larger than (M2). 77K (M3) is the energy gap T of the first compound at 77 [K] 77K It is preferable that it is larger than (M1).
[0457] Energy gap T at 77 [K] of the first compound 77K (M1) and the energy gap T at 77 [K] of the second compound 77K (M2) and the energy gap T at 77 [K] of the third compound 77K It is preferable that (M3) satisfies the relationship of the following mathematical formula (Mathematical Formula 3B): T 77K (M3) > T 77K (M2) > T 77K (M1) ...(Math 3B)
[0458] In the organic EL device according to the first embodiment, the lowest excited singlet energy S 1 (M1) and the lowest excited singlet energy S of the second compound 1 (M2) and the lowest excited singlet energy S of the fourth compound 1 (M4) preferably satisfy the relationship of the following mathematical formula (Mathematical Formula 3C): 1 (M4) > S 1 (M2) > S 1 (M1) ...(Math 3C)
[0459] The energy gap T at 77[K] of the fourth compound 77K(M4) is the energy gap T at 77 [K] of the second compound 77K The energy gap T at 77 [K] of the fourth compound is preferably larger than (M2). 77K (M4) is the energy gap T of the first compound at 77 [K] 77K It is preferable that it is larger than (M1).
[0460] Energy gap T at 77 [K] of the first compound 77K (M1) and the energy gap T at 77 [K] of the second compound 77K (M2) and the energy gap T at 77 [K] of the fourth compound 77K It is preferable that (M4) satisfies the relationship of the following mathematical formula (Mathematical Formula 3D): T 77K (M4) > T 77K (M2) > T 77K (M1) ...(Math 3D)
[0461] When the organic EL element of the first embodiment is caused to emit light, it is preferable that the fluorescent compound in the light-emitting layer mainly emits light.
[0462] The organic EL element of the first embodiment preferably emits red or green light. When the organic EL element of the first embodiment emits green light, the maximum peak wavelength of the light emitted from the organic EL element is preferably 500 nm or more and 560 nm or less. When the organic EL element of the first embodiment emits red light, the maximum peak wavelength of the light emitted from the organic EL element is preferably 600 nm or more and 660 nm or less. When the organic EL element of the first embodiment emits blue light, the maximum peak wavelength of the light emitted from the organic EL element is preferably 430 nm or more and 480 nm or less.
[0463] The maximum peak wavelength of light emitted from the organic EL element is measured as follows: 2A voltage is applied to the organic EL element so that the spectral radiance spectrum obtained is measured using a spectroradiometer CS-2000 (manufactured by Konica Minolta, Inc.) In the obtained spectral radiance spectrum, the peak wavelength of the emission spectrum at which the emission intensity is maximum is measured, and this is defined as the maximum peak wavelength (unit: nm).
[0464] (Compound Content in Light-Emitting Layer) The contents of the first compound, second compound, third compound, and fourth compound contained in the light-emitting layer are preferably within the following ranges, for example. The content of the first compound in the light-emitting layer is more preferably 0.3% by mass or more and 4.0% by mass or less, even more preferably 0.3% by mass or more and 3.0% by mass or less, and even more preferably 0.3% by mass or more and 2.0% by mass or less. The content of the second compound in the light-emitting layer is 30% by mass or more and 50% by mass or less. The content of the second compound in the light-emitting layer is preferably 30% by mass or more and 45% by mass or less, more preferably 35% by mass or more and 45% by mass or less, and even more preferably 35% by mass or more and 40% by mass or less. The total content of the third compound and the fourth compound in the light-emitting layer is preferably 46% by mass or more and 69.7% by mass or less, more preferably 52% by mass or more and 69.7% by mass or less, and even more preferably 58% by mass or more and 69.7% by mass or less.
[0465] In one aspect of the organic EL element according to the first embodiment, the mass content of one of the third compound and the fourth compound in the light-emitting layer is greater than the mass content of the second compound in the light-emitting layer, and the mass content of the other of the third compound and the fourth compound in the light-emitting layer is less than the mass content of the second compound in the light-emitting layer.
[0466] In one aspect of the organic EL element according to the first embodiment, the mass content of the fourth compound in the light-emitting layer is greater than the mass content of the second compound in the light-emitting layer.
[0467] In one aspect of the organic EL element according to the first embodiment, the mass content of the third compound in the light-emitting layer is lower than the mass content of the second compound in the light-emitting layer.
[0468] In one aspect of the organic EL element according to the first embodiment, the mass content of the third compound in the light-emitting layer is smaller than the mass content of the second compound in the light-emitting layer, and the mass content of the fourth compound in the light-emitting layer is smaller than the mass content of the second compound in the light-emitting layer.
[0469] The upper limit of the total content of the first compound, the second compound, the third compound, and the fourth compound in the light-emitting layer is 100% by mass. Note that this embodiment does not exclude the light-emitting layer containing materials other than the first compound, the second compound, the third compound, and the fourth compound. The light-emitting layer may contain only one type of first compound, or two or more types. The light-emitting layer may contain only one type of second compound, or two or more types. The light-emitting layer may contain only one type of third compound, or two or more types. The light-emitting layer may contain only one type of fourth compound, or two or more types.
[0470] (TADF mechanism) FIG. 5 is a diagram showing an example of the relationship between the energy levels of a first compound, a second compound, a third compound, and a fourth compound in an emitting layer. In FIG. 5, S0 represents the ground state. S1(M1) represents the lowest excited singlet state of the first compound, and T1(M1) represents the lowest excited triplet state of the first compound. S1(M2) represents the lowest excited singlet state of the second compound, and T1(M2) represents the lowest excited triplet state of the second compound. S1(M3) represents the lowest excited singlet state of the third compound, and T1(M3) represents the lowest excited triplet state of the third compound. S1(M4) represents the lowest excited singlet state of the fourth compound, and T1(M4) represents the lowest excited triplet state of the fourth compound. The dashed arrow from S1(M2) to S1(M1) in FIG. 5 represents a Förster energy transfer from the lowest excited singlet state of the second compound to the lowest excited singlet state of the first compound. As shown in FIG. 5, when a compound with a small ΔST(M2) is used as the second compound, the lowest excited triplet state T1(M2) can undergo reverse intersystem crossing to the lowest excited singlet state S1(M2) due to thermal energy. Then, a Förster energy transfer occurs from the lowest excited singlet state S1(M2) of the second compound to the first compound, generating the lowest excited singlet state S1(M1). As a result, fluorescence emission from the lowest excited singlet state S1(M1) of the first compound can be observed. It is believed that the internal quantum efficiency can theoretically be increased to 100% by utilizing delayed fluorescence due to this TADF mechanism. The magnitude relationship between the energy levels of S1(M3) and S1(M4) and the magnitude relationship between the energy levels of T1(M3) and T1(M4) are not limited to those shown in FIG.
[0471] (Thickness of the Light-Emitting Layer) The thickness of the light-emitting layer in the organic EL element of the first embodiment is preferably 5 nm or more and 50 nm or less, more preferably 7 nm or more and 50 nm or less, and even more preferably 10 nm or more and 50 nm or less. A thickness of 5 nm or more facilitates the formation of the light-emitting layer and the adjustment of chromaticity, while a thickness of 50 nm or less facilitates the suppression of an increase in driving voltage.
[0472] <Hole Transport Zone> One embodiment of the hole transport zone includes, in order from the anode side, a hole transport layer, a first electron blocking layer, and a second electron blocking layer. Another embodiment of the hole transport zone includes, in order from the anode side, a hole injection layer, a hole transport layer, a first electron blocking layer, and a second electron blocking layer (see FIG. 1). Another embodiment of the hole transport zone includes, in order from the anode side, a hole injection layer, a hole transport layer, and a third electron blocking layer (see FIG. 2). The hole transport zone is not limited to these, and may further include one or more organic layers. For example, the hole transport layer may be a layer consisting of two or more organic layers.
[0473] In one aspect of the organic EL element of the first embodiment, the anode and the hole injection layer are in direct contact with each other. In one aspect of the organic EL element of the first embodiment, the hole injection layer and the hole transport layer are in direct contact with each other. In one aspect of the organic EL element of the first embodiment, the first electron blocking layer and the hole transport layer are in direct contact with each other. In one aspect of the organic EL element of the first embodiment, the light-emitting layer and the second electron blocking layer are in direct contact with each other. In one aspect of the organic EL element of the first embodiment, the first electron blocking layer and the second electron blocking layer are in direct contact with each other. In one aspect of the organic EL element of the first embodiment, the third electron blocking layer and the hole transport layer are in direct contact with each other. In one aspect of the organic EL element of the first embodiment, the light-emitting layer and the third electron blocking layer are in direct contact with each other.
[0474] In one aspect of the organic EL element of the first embodiment, the thickness of the first electron blocking layer is 35 nm or less, or 30 nm or less. In one aspect of the organic EL element of the first embodiment, the thickness of the second electron blocking layer is 10 nm or less, or 5 nm or less. The thickness of the second electron blocking layer of 10 nm or less is likely to contribute to a decrease in driving voltage.
[0475] In one aspect of the organic EL element of the first embodiment, the film thickness of the first electron blocking layer is thicker than the film thickness of the second electron blocking layer. Having the film thickness of the first electron blocking layer thicker than the film thickness of the second electron blocking layer facilitates contributing to a reduction in driving voltage. In one aspect of the organic EL element of the first embodiment, the sum of the film thicknesses of the first electron blocking layer and the second electron blocking layer is 40 nm or less, or 35 nm or less. Having the sum of the film thicknesses of the first electron blocking layer and the second electron blocking layer is 40 nm or less facilitates contributing to an improvement in luminous efficiency. In one aspect of the organic EL element of the first embodiment, the sum of the film thicknesses of the first electron blocking layer and the second electron blocking layer is 30 nm or more.
[0476] In one aspect of the organic EL element of the first embodiment, the thickness of the hole transport layer is 30 nm or more, 80 nm or more, or 110 nm or more. A thickness of the hole transport layer of 30 nm or more can easily contribute to improving the luminous efficiency.
[0477] In one aspect of the organic EL element of the first embodiment, when the hole-transporting region includes a hole-transporting layer, a first electron-blocking layer, and an electron-blocking layer, the total thickness of the hole-transporting layer, the first electron-blocking layer, and the second electron-blocking layer is 160 nm or less, or 155 nm or less. In one aspect of the organic EL element of the first embodiment, the total thickness of the hole-transporting layer, the first electron-blocking layer, and the second electron-blocking layer is 120 nm or more.
[0478] (Second Electron Blocking Layer) In one aspect of the organic EL element according to the first embodiment, the second electron blocking layer contains a compound represented by the following general formula (5) (hereinafter also referred to as a second electron blocking material).
[0479]
[0480] (In the general formula (5), L A1 , L A2 and L A3 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, and *2 is LA1 , L A2 or L A3 is the bonding position with Ar 511 , Ar 512 and Ar 513 each independently represents a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, —Si(R C1 ) (R C2 ) (R C3 ) or a group represented by the general formula (5A), 511 , Ar 512 , and Ar 513 At least one of the groups represented by the general formula (5A) is a group represented by the general formula (5A), and when two or more groups represented by the general formula (5A) are present, the two or more groups represented by the general formula (5A) are the same as or different from each other, and R C1 , R C2 and R C3 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R C1 If there are multiple R C1 are the same or different from each other, R C2 If there are multiple R C2 are the same or different from each other, R C3 If there are multiple R C3 are the same or different from each other, and in the general formula (5A), X 5 is an oxygen atom, a sulfur atom, C(R 51A ) (R 52A ) or N(R 53A ) and R 51A and R 52A are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and R51 ~R 58 one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 51 ~R 58 , R 51A , R 52A and R 53A one of R is a single bond bonding to *1, R is not a single bond bonding to *1, does not form the substituted or unsubstituted monocyclic ring, and does not form the substituted or unsubstituted fused ring 51 ~R 58 , R 51A , R 52A and R 53A are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, 901 ~R 904 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R 901 If there are multiple R 901 are the same or different from each other, R 902 If there are multiple R 902 are the same or different from each other, R 903 If there are multiple R 903 are the same or different from each other, R904 If there are multiple R 904 are the same or different from each other.)
[0481] In the general formula (5), L A1 , L A2 or L A3 is a single bond, *2 is the bonding position to the nitrogen atom in the general formula (5).
[0482] In one embodiment of the second electron blocking material, L A1 , L A2 and L A3 are each independently a single bond, a substituted or unsubstituted furanylene group, a substituted or unsubstituted thienylene group, a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted terphenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted phenanthrylene group, a substituted or unsubstituted fluorenylene group, a substituted or unsubstituted carbazolylene group, a substituted or unsubstituted dibenzofuranylene group, or a substituted or unsubstituted dibenzothienylene group. A1 , L A2 and L A3 are each independently a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted terphenylene group, a substituted or unsubstituted naphthylene group, or a substituted or unsubstituted phenanthrylene group.
[0483] In one aspect of the organic EL element of the first embodiment, the second electron blocking material is a compound represented by the following general formula (50).
[0484]
[0485] (In the general formula (50), Ar 511 , Ar 512 and Ar 513 are respectively Ar in the general formula (5). 511 , Ar 512 and Ar 513 n1 is 4, and four Ra 11are the same or different from each other, and the four Ra 11 one or more pairs of adjacent two or more of 12 are the same or different from each other, and the four Ra 12 one or more pairs of adjacent two or more of 13 are the same or different from each other, and the four Ra 13 one or more pairs of adjacent two or more of Ra are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other to form the substituted or unsubstituted monocycle and the substituted or unsubstituted fused ring; 11 , Ra 12 and Ra 13 each independently represents a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, 901 ~R 904 are R in the general formula (5A), respectively. 901 ~R 904 is synonymous with
[0486] In one aspect of the organic EL element of the first embodiment, the second electron blocking material is a compound represented by the following general formula (500).
[0487]
[0488] (In the general formula (500), Ar 511 , Ar 512 , Ar 513 , Ra 12 , Ra 13 , n2 and n3 are each Ar in the general formula (50). 511 , Ar 512 , Ar 513 , Ra 12 , Ra 13 , n2 and n3 are synonymous with each other.)
[0489] In one aspect of the organic EL element of the first embodiment, Ar in the second electron blocking material 511 , Ar 512 , and Ar 513 At least one of the groups is a group represented by any one of the following general formulas (51) and (61) to (64).
[0490]
[0491] (In the general formulae (51) and (61) to (64), R 51 ~R 58 are R in the general formula (5A), respectively. 51 ~R 58 * in the general formulae (51) and (61) to (64) each independently represents L in the general formula (5) A1 , L A2 and L A3 (the bonding position with *2 in the general formula (5) above, the bonding position with a carbon atom constituting a benzene ring in the general formula (50) above, or the bonding position with a nitrogen atom or a carbon atom constituting a benzene ring in the general formula (500) above).
[0492] In one embodiment of the second electron barrier material, Ar 511 , Ar 512 , and Ar 513 At least one of the groups is a group represented by any one of the following general formulas (51) to (80).
[0493]
[0494] (In the general formulas (51) to (55), R 51 ~R 58 and R 53A are R in the general formula (5A), respectively. 51 ~R 58 and R 53A * each independently represents L in formula (5). A1 , L A2 and L A3 (the bonding position with *2 in the general formula (5)), the bonding position with a carbon atom constituting a benzene ring in the general formula (50), or the bonding position with a nitrogen atom or a carbon atom constituting a benzene ring in the general formula (500).
[0495]
[0496] (In the general formulas (56) to (60), R 51 ~R 58 , R 51A and R 52A are R in the general formula (5A), respectively. 51 ~R 58 , R 51A and R 52A * each independently represents L in formula (5). A1 , L A2 and L A3 (the bonding position with *2 in the general formula (5)), the bonding position with a carbon atom constituting a benzene ring in the general formula (50), or the bonding position with a nitrogen atom or a carbon atom constituting a benzene ring in the general formula (500).
[0497]
[0498] (In the general formulas (61) to (68), R 51 ~R 58 are R in the general formula (5A), respectively. 51 ~R 58 and * each independently represents L in formula (5). A1 , L A2 and L A3(the bonding position with *2 in the general formula (5)), the bonding position with a carbon atom constituting a benzene ring in the general formula (50), or the bonding position with a nitrogen atom or a carbon atom constituting a benzene ring in the general formula (500).
[0499]
[0500]
[0501] (In the general formulas (69) to (80), R 51 ~R 58 and X 5 are R in the general formula (5A), respectively. 51 ~R 58 and X 5 is synonymous with R 51B ~R 54B one or more pairs of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other to form the substituted or unsubstituted monocycle and the substituted or unsubstituted fused ring 51B ~R 54B are each independently a single bond bonded to *1, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring, R in the general formula (5A). 51 ~R 58 * each independently represents L in formula (5). A1 , L A2 and L A3 (the bonding position with *2 in the general formula (5)), the bonding position with a carbon atom constituting a benzene ring in the general formula (50), or the bonding position with a nitrogen atom or a carbon atom constituting a benzene ring in the general formula (500).
[0502] In one embodiment of the second electron barrier material, Ar 511 , Ar 512 , and Ar 513 At least one of these is a group represented by the general formula (51).
[0503] In one embodiment of the second electron barrier material, Ar 511 , Ar 512 , and Ar 513 At least one of these is a group represented by the general formula (64).
[0504] In one embodiment of the second electron barrier material, Ar 511 , Ar 512 , and Ar 513 At least one of the groups represented by any one of the general formulas (51) to (80) is a group represented by any one of the general formulas (51) to (80). 511 , Ar 512 , and Ar 513 In one embodiment of the second electron-blocking material, two of the Ar groups are groups represented by any one of the general formulas (51) to (80). 511 , Ar 512 , and Ar 513 Among them, three are groups represented by any one of the general formulas (51) to (80). 511 , Ar 512 , and Ar 513 Among them, three are groups represented by any one of the general formulas (51) and (61) to (64). 511 , Ar 512 , and Ar 513 When two or three of the groups are groups represented by any of the general formulae (51) to (80), two or three of Ar 511 , Ar 512 , and Ar 513 are either identical to or different from each other.
[0505] In one embodiment of the second electron barrier material, Ar 511 , Ar 512 , and Ar 513 Among them, Ar is not a group represented by the general formula (5A). 511 , Ar 512 , and Ar 513 are each independently a group represented by any one of the following general formulas (5B) to (12B).511 , Ar 512 , and Ar 513 When two of the groups are not the group represented by general formula (5A), the two groups are the same or different.
[0506]
[0507] (In the general formulae (5B) to (7B), R 41 ~R 45 At least one pair of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 40A , R 40B and R 40C At least one pair of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and a plurality of R 40A are the same or different from each other, and a plurality of R 40B are the same or different from each other, and a plurality of R 40C are the same or different from each other, and in the general formulae (8B) to (10B), R 40 ~R 43 , R 46 ~R 49 and R 40A At least one pair of adjacent two or more R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and a plurality of R 40A are the same or different from each other, and in the general formulae (11B) to (12B), X 6 is an oxygen atom, a sulfur atom, C(R 51C ) (R 52C ) or N(R 53C ) and R 51C and R 52Care bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and R 41A ~R 44A and one or more pairs of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and in the general formulae (5B) to (12B), R do not form the substituted or unsubstituted monocycle and do not form the substituted or unsubstituted fused ring. 40 ~R 49 , R 40A , R 40B , R 40C , R 41A ~R 44A , R 51C , R 52C , and R 53C are each independently a single bond bonded to *1, do not form the substituted or unsubstituted monocycle, and do not form the substituted or unsubstituted fused ring, R in the general formula (5A). 51 ~R 58 * each independently represents L in formula (5). A1 , L A2 and L A3 or a bonding position to a carbon atom constituting a benzene ring in the general formula (50), or a bonding position to a nitrogen atom or a carbon atom constituting a benzene ring in the general formula (500).
[0508] In one embodiment of the second electron blocking material, R 51 ~R 58 , R 51A , R 52A and R 53A are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms. 51~R 58 , R 51A , R 52A and R 53A are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 18 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
[0509] In one embodiment of the second electron blocking material, R 40 ~R 49 , R 40A , R 40B , R 40C , R 41A ~R 44A , R 51B ~R 54B , R 51C , R 52C , R 53C , Ra 11 , Ra 12 and Ra 13 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms. 40 ~R 49 , R 40A , R 40B , R 40C , R 41A ~R 44A , R 51B ~R 54B , R 51C , R 52C , R 53C , Ra 11 , Ra 12 and Ra 13 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 18 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
[0510] In one embodiment of the second electron-blocking material, the substituents in the term "substituted or unsubstituted" are each independently a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms, or -N(R 906 ) (R 907 ) is a group represented by R 906 and R 907 are each independently R in the general formula (5A). 901 ~R 904 is synonymous with R 906 If there are multiple R 906 are the same or different from each other, R 907 If there are multiple R 907 are the same or different from each other.
[0511] In one embodiment of the second electron-blocking material, the substituents in the term "substituted or unsubstituted" are each independently a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, or -N(R 906 ) (R 907 In one embodiment of the second electron-blocking material, the substituent in the case of "substituted or unsubstituted" is an "unsubstituted" group or a group represented by -N(R 906 ) (R 907 ) and is a group represented by —N(R 906 ) (R 907 ) in R 906 and R 907 are all unsubstituted groups. In one embodiment of the second electron-blocking material, the substituent in the term "substituted or unsubstituted" is an "unsubstituted" group.
[0512] The second electron blocking layer contains the second electron blocking material in an amount of 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or 99% by mass or more. The second electron blocking layer may be a layer containing only the second electron blocking material.
[0513] (Method for Producing Second Electron-Blocking Material) The second electron-blocking material can be produced by a known method.
[0514] (Specific Examples of Second Electron-Blocking Material) Specific examples of the second electron-blocking material include the following compounds: However, the present invention is not limited to these specific examples of compounds.
[0515]
[0516]
[0517]
[0518]
[0519]
[0520]
[0521]
[0522]
[0523]
[0524]
[0525]
[0526] (First Electron-Blocking Layer) In one aspect of the organic EL element according to the first embodiment, the first electron-blocking layer contains a compound represented by the following general formula (4) (hereinafter also referred to as a first electron-blocking material): The first electron-blocking material and the second electron-blocking material are preferably different compounds.
[0527]
[0528] (In the general formula (4), L A1 , LA2 and L A3 are each independently a single bond, a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted divalent heterocyclic group having 5 to 50 ring atoms, and *4 is L A1 , L A2 or L A3 is the bonding position with Ar 411 , Ar 412 and Ar 413 each independently represents a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, —Si(R C1 ) (R C2 ) (R C3 ) or a group represented by the general formula (4A), 411 , Ar 412 , and Ar 413 At least one of the groups represented by the general formula (4A) is a group represented by the general formula (4A), and when two or more groups represented by the general formula (4A) are present, the two or more groups represented by the general formula (4A) are the same as or different from each other, and R C1 , R C2 and R C3 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R C1 If there are multiple R C1 are the same or different from each other, R C2 If there are multiple R C2 are the same or different from each other, R C3 If there are multiple R C3 are the same or different from each other, and in the general formula (4A), X 5 is an oxygen atom, a sulfur atom, C(R 51A ) (R 52A ) or N(R 53A) and R 51A and R 52A are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, and R 51 ~R 58 At least one pair of adjacent two or more of R are bonded to each other to form a substituted or unsubstituted monocyclic ring, or are bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other, 51 ~R 58 , R 51A , R 52A and R 53A one of R is a single bond bonded to *3, R is not a single bond bonded to *3, does not form the substituted or unsubstituted monocyclic ring, and does not form the substituted or unsubstituted fused ring 51 ~R 58 , R 51A , R 52A and R 53A are each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, 901 ~R 904 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, R 901 If there are multiple R 901 are the same or different from each other, R902 If there are multiple R 902 are the same or different from each other, R 903 If there are multiple R 903 are the same or different from each other, R 904 If there are multiple R 904 are the same or different from each other.)
[0529] In the general formula (4), L A1 , L A2 or L A3 is a single bond, *4 is the bonding position to the nitrogen atom in the general formula (4).
[0530] In one embodiment of the first electron-blocking material, L A1 , L A2 and L A3 are each independently a single bond, a substituted or unsubstituted phenylene group, a substituted or unsubstituted biphenylene group, a substituted or unsubstituted terphenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted phenanthrylene group, or a substituted or unsubstituted fluorenylene group. A1 , L A2 and L A3 are each independently a single bond, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted biphenylene group.
[0531] In one aspect of the organic EL element of the first embodiment, the first electron-blocking material is a compound represented by the following general formula (40), (41), or (42).
[0532]
[0533] (In the general formulas (40) to (42), Ar 411 , Ar 412 and Ar 413 are respectively Ar in the general formula (4). 411 , Ar 412 and Ar 413 n2 is 4, and four Ra 12are the same or different from each other, and the four Ra 12 one or more pairs of adjacent two or more of 13 are the same or different from each other, and the four Ra 13 one or more pairs of adjacent two or more of Ra are bonded to each other to form a substituted or unsubstituted monocycle, or bonded to each other to form a substituted or unsubstituted fused ring, or are not bonded to each other to form the substituted or unsubstituted monocycle and the substituted or unsubstituted fused ring; 12 and Ra 13 each independently represents a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, -Si(R 901 ) (R 902 ) (R 903 a group represented by —O—(R 904 a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms, 901 ~R 904 are R in the general formula (4A), respectively. 901 ~R 904 is synonymous with
[0534] In one embodiment of the first electron barrier material, Ar 411 , Ar 412 , and Ar 413 At least one of these is a group represented by any one of the general formulae (56A) to (68A).
[0535]
[0536] (In the general formulae (56A) to (60A), R 51 ~R 58 , R 51A and R52A are R in the general formula (4A), respectively. 51 ~R 58 , R 51A and R 52A * each independently represents L in formula (4). A1 , L A2 and L A3 (*4 in the general formula (4)), or the bonding position to a nitrogen atom or a carbon atom constituting a benzene ring in the general formulas (40) to (41), or the bonding position to a nitrogen atom in the general formula (42).
[0537]
[0538] (In the general formulae (61A) to (68A), R 51 ~R 58 are R in the general formula (4A), respectively. 51 ~R 58 * each independently represents L in formula (4). A1 , L A2 and L A3 (*4 in the general formula (4)), or the bonding position to a nitrogen atom or a carbon atom constituting a benzene ring in the general formulas (40) to (41), or the bonding position to a nitrogen atom in the general formula (42).
[0539] In one embodiment of the first electron barrier material, Ar 411 , Ar 412 , and Ar 413 At least one of the groups represented by any one of the general formulas (56A) to (68A) is a group represented by any one of the general formulas (56A) to (68A). 411 , Ar 412 , and Ar 413 At least one of the groups represented by any one of the general formulas (56A) to (60A) is a group represented by any one of the general formulas (56A) to (60A). 411 , Ar 412 , and Ar 413In one embodiment of the first electron-blocking material, two of the Ar groups are groups represented by any one of the general formulas (56A) to (68A). 411 , Ar 412 , and Ar 413 In one embodiment of the first electron-blocking material, two of the Ar groups are represented by any one of the general formulas (56A) to (60A). 411 , Ar 412 , and Ar 413 Among them, three are groups represented by any one of the general formulas (56A) to (68A). 411 , Ar 412 , and Ar 413 Among them, three are groups represented by any one of the general formulas (56A) to (60A). 411 , Ar 412 , and Ar 413 When two or three of the groups are groups represented by any of the general formulae (56A) to (68A), two or three of the groups represented by Ar 411 , Ar 412 , and Ar 413 are either identical to or different from each other.
[0540] In one embodiment of the first electron barrier material, Ar 411 , Ar 412 , and Ar 413 Among them, Ar is not a group represented by the general formula (4A). 411 , Ar 412 , and Ar 413 are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, or a substituted or unsubstituted phenanthryl group. 411 , Ar 412 , and Ar 413 Among them, Ar is not a group represented by the general formula (4A). 411 , Ar 412 , and Ar 413are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group. 411 , Ar 412 , and Ar 413 When two of the groups are not the group represented by general formula (4A), the two groups are the same or different.
[0541] In one embodiment of the first electron blocking material, R 51 ~R 58 , R 51A , R 52A , R 53A , Ra 12 and Ra 13 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 50 ring atoms. 51 ~R 58 , R 51A , R 52A , R 53A , Ra 12 and Ra 13 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 18 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 18 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 18 ring atoms.
[0542] In one embodiment of the first electron-barrier material, the substituents in the term "substituted or unsubstituted" are each independently a group represented by a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms.
[0543] In one embodiment of the first electron-barrier material, the substituents in the case of "substituted or unsubstituted" are each independently a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted naphthyl group, or a substituted or unsubstituted phenanthrenyl group. In one embodiment of the first electron-barrier material, the substituents in the case of "substituted or unsubstituted" are "unsubstituted" groups.
[0544] The first electron blocking layer contains the first electron blocking material in an amount of 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or 99% by mass or more. The first electron blocking layer may be a layer containing only the first electron blocking material.
[0545] In one aspect of the organic EL element of the first embodiment, the first electron-blocking material satisfies the following formula (53), formula (53A), or formula (53B). When the first electron-blocking material satisfies the following formula (53), the driving voltage is likely to decrease. (Formula 53): μ H (EM1)≧1.0×10 -4 cm 2 / Vs (Math. 53A): μ H (EM1)≧1.0×10 -3 cm 2 / Vs (Math. 53B): μ H (EM1)≧1.0×10 -2 cm 2 / Vs (μ H (EM1) is the hole mobility of the first electron blocking material.
[0546] (Method of Measuring Hole Mobility) Hole mobility can be measured by performing impedance measurement using a mobility evaluation element prepared by the following procedure. The mobility evaluation element is prepared, for example, by the following procedure. On a glass substrate with an ITO transparent electrode (anode), the following compounds HT-1 and HA are co-deposited so as to cover the transparent electrode, thereby forming a hole injection layer. On this hole injection layer, compound HT-1 is deposited by deposition to form a first hole transport layer. Subsequently, compound HT-2 is deposited by deposition on the first hole mobility layer to form a second hole transport layer. Subsequently, on the second hole mobility layer, hole mobility μ H The compound Target to be measured is vapor-deposited to form a measurement target layer. Metallic aluminum (Al) is vapor-deposited on this measurement target layer to form a metal cathode. The above mobility evaluation device configuration is shown in simplified form as follows: ITO(130) / HT-1:HA(10,97%:3%) / HT-1(10) / HT-2(10) / Target(200) / Al(80) In the mobility evaluation device configuration, the numbers in parentheses indicate the film thickness (unit: nm). Similarly, in the mobility evaluation device configuration, the numbers in parentheses expressed as percentages (97%:3%) indicate the proportions (mass %) of compound HT-1 and compound HA in the hole injection layer.
[0547]
[0548] The hole mobility evaluation device is placed in an impedance measurement device, and impedance measurement is performed. The impedance measurement is performed by sweeping the measurement frequency from 1 Hz to 1 MHz. At this time, a DC voltage V is applied to the device simultaneously with an AC amplitude of 0.1 V. From the measured impedance Z, the modulus M is calculated using the relationship in the following calculation formula (C1). Calculation formula (C1): M = jωZ. In the above calculation formula (C1), j is an imaginary unit whose square is -1, and ω is the angular frequency [rad / s]. In a Bode plot with the imaginary part of the modulus M on the vertical axis and frequency [Hz] on the horizontal axis, the electrical time constant τ of the mobility evaluation device is calculated from the frequency fmax showing the peak using the following calculation formula (C2): Calculation formula (C2): τ = 1 / (2πfmax). In the above calculation formula (C2), π is the symbol for pi. Using τ calculated from the above formula (C2), the hole mobility μ H Calculate the formula (C3-2): μ H = d 2 / (Vτ) In the above formula (C3-2), d is the total film thickness of the organic thin films that constitute the device, and in the case of the device configuration for evaluating the hole mobility, d=230 [nm].
[0549] The hole mobility in this specification is expressed as the square root of the electric field strength, E 1/2 = 500 [V 1/2 / cm 1/2 The square root of the electric field strength E 1/2 can be calculated from the relationship of the following calculation formula (C4): 1/2 =V 1/2 / d 1/2 The impedance measurement is performed using a Solartron 1260 model impedance measuring device, and for higher accuracy, a Solartron 1296 model dielectric constant measurement interface can also be used.
[0550] (Method for Producing First Electron-Blocking Material) The first electron-blocking material can be produced by a known method.
[0551] (Specific Examples of First Electron-Blocking Material) Specific examples of the first electron-blocking material include the following compounds: However, the present invention is not limited to these specific examples of compounds.
[0552]
[0553]
[0554] (Third Electron Blocking Layer) In one aspect of the organic EL element according to the first embodiment, when the hole-transporting region includes, in order from the anode side, a hole-injection layer, a hole-transporting layer, and a third electron-blocking layer (see FIG. 2), the third electron-blocking layer includes a third electron-blocking material. As the third electron-blocking material, a compound represented by the general formula (5) or a compound represented by the general formula (4) may be used. The film thickness of the third electron-blocking layer is preferably 5 nm or more and 35 nm or less.
[0555] (Hole Transport Layer) One aspect of the organic EL element of the first embodiment includes a hole transport layer between the anode and the first electron blocking layer, and the hole transport layer includes a hole transport material. Examples of the hole transport material include the "materials that can be used in the hole transport layer (e.g., aromatic amine compounds, carbazole derivatives, and anthracene derivatives)" described in the <Configuration of Organic EL Element> section below. Examples of the hole transport material include a monoamine compound having one substituted or unsubstituted amino group in the molecule, or a diamine compound having two substituted or unsubstituted amino groups in the molecule. The hole transport material may be a compound having a substituted or unsubstituted carbazolyl group and one substituted or unsubstituted amino group in the molecule. The hole transport material may be a compound represented by the general formula (5) or a compound represented by the general formula (4).
[0556] (Hole Injection Layer) One aspect of the organic EL element of the first embodiment includes a hole injection layer between the anode and the hole transport layer. For example, the "substance with high hole injection properties" described in the <Configuration of Organic EL Element> below can be used as the hole injection layer. In one aspect of the organic EL element of the first embodiment, the hole injection layer may be composed of only one material. In one aspect of the organic EL element of the first embodiment, the hole injection layer contains an acceptor material. In one aspect of the organic EL element of the first embodiment, the hole injection layer contains a first organic material and an acceptor material. The first organic material and the acceptor material are different compounds. The first organic material is, for example, a monoamine compound having one substituted or unsubstituted amino group in the molecule, or a diamine compound having two substituted or unsubstituted amino groups in the molecule. The first organic material may be a compound represented by the general formula (5) or a compound represented by the general formula (4). In one aspect of the organic EL element of the first embodiment, the first organic material contained in the hole injection layer and the hole transport material contained in the hole transport layer are the same as or different from each other. In one aspect of the organic EL element of the first embodiment, the content of the acceptor material in the hole injection layer is less than 50 mass %.
[0557] <Configuration of Organic EL Element> The configuration of the organic EL element will be further described.
[0558] (Substrate) The substrate is used as a support for the organic EL element. For example, glass, quartz, plastic, etc. can be used as the substrate. A flexible substrate may also be used. A flexible substrate is a substrate that can be bent (flexible), and examples thereof include a plastic substrate. Examples of materials for forming the plastic substrate include polycarbonate, polyarylate, polyethersulfone, polypropylene, polyester, polyvinyl fluoride, polyvinyl chloride, polyimide, and polyethylene naphthalate. Inorganic vapor deposition films can also be used.
[0559] (Anode) For the anode formed on the substrate, it is preferable to use a metal, alloy, electrically conductive compound, or mixture thereof having a large work function (specifically, 4.0 eV or more). Specific examples include indium oxide-tin oxide (ITO), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, tungsten oxide, indium oxide containing zinc oxide, graphene, etc. Other 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 metal materials (e.g., titanium nitride).
[0560] These materials are usually formed into films by sputtering. For example, indium oxide-zinc oxide can be formed by sputtering using a target containing 1 mass % to 10 mass % of zinc oxide added to indium oxide. Furthermore, for example, indium oxide containing tungsten oxide and zinc oxide can be formed by sputtering using a target containing 0.5 mass % to 5 mass % of tungsten oxide and 0.1 mass % to 1 mass % of zinc oxide relative to indium oxide. Alternatively, the films may be formed by vacuum deposition, coating, inkjet printing, spin coating, or the like.
[0561] Of the EL layers formed on the anode, the hole injection layer formed in contact with the anode is formed using a composite material that facilitates hole injection regardless of the work function of the anode, and therefore materials that can be used as electrode materials (for example, metals, alloys, electrically conductive compounds, and mixtures thereof, as well as elements belonging to Group 1 or Group 2 of the periodic table) can be used.
[0562] Materials with low work functions, such as elements belonging to Group 1 or 2 of the periodic table, can also be used, including alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as magnesium (Mg), calcium (Ca), and strontium (Sr), and alloys containing these (e.g., MgAg, AlLi), rare earth metals such as europium (Eu), ytterbium (Yb), and alloys containing these. When forming an anode using alkali metals, alkaline earth metals, and alloys containing these, vacuum deposition or sputtering can be used. Furthermore, when using silver paste or the like, coating or inkjet printing can be used.
[0563] When the organic EL element is a bottom-emission type, the anode is preferably formed of a metal material having optical transparency or semi-transparency that transmits light from the light-emitting layer. In this specification, optical transparency or semi-transparency means a property that transmits 50% or more (preferably 80% or more) of the light emitted from the light-emitting layer. The optically transparent or semi-transparent metal material can be appropriately selected from the materials listed in the anode section.
[0564] When the organic EL device is a top-emission type, the anode is a reflective electrode having a reflective layer. The reflective layer is preferably formed of a metal material having optical reflectivity. In this specification, optical reflectivity means the property of reflecting 50% or more (preferably 80% or more) of the light emitted from the light-emitting layer. The metal material having optical reflectivity can be appropriately selected from the materials listed in the anode section. The anode may be composed of only a reflective layer, or may have a multilayer structure having a reflective layer and a conductive layer (preferably a transparent conductive layer). When the anode has a reflective layer and a conductive layer, it is preferable that the conductive layer be disposed between the reflective layer and the hole-transporting region. The conductive layer can be appropriately selected from the materials listed in the anode section.
[0565] (Cathode) For the cathode, it is preferable to use a metal, alloy, electrically conductive compound, or mixture thereof having a small work function (specifically, 3.8 eV or less). Specific examples of such a cathode material include elements belonging to Group 1 or 2 of the periodic table, i.e., alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as magnesium (Mg), calcium (Ca), and strontium (Sr), alloys containing these (e.g., MgAg, AlLi), rare earth metals such as europium (Eu), ytterbium (Yb), and alloys containing these.
[0566] When an alkali metal, an alkaline earth metal, or an alloy containing these is used to form a cathode, a vacuum deposition method or a sputtering method can be used. When a silver paste or the like is used, a coating method or an inkjet method can be used.
[0567] By providing an electron injection layer, the cathode can be formed using various conductive materials, regardless of the magnitude of the work function, such as Al, Ag, ITO, graphene, indium oxide-tin oxide containing silicon or silicon oxide, etc. These conductive materials can be formed into films by a sputtering method, an inkjet method, a spin coating method, or the like.
[0568] When the organic EL element is a bottom-emission type, the cathode is a reflective electrode. The reflective electrode is preferably formed of a metal material having light reflectivity. The metal material having light reflectivity can be appropriately selected from the materials listed in the section on the cathode.
[0569] When the organic EL element is a top-emission type, the cathode is preferably formed of a light-transmitting or semi-transmitting metal material that transmits light from the light-emitting layer. The light-transmitting or semi-transmitting metal material can be appropriately selected from the materials listed in the cathode section.
[0570] The organic EL element according to the first embodiment may be a bottom-emission organic EL element. Alternatively, the organic EL element according to the first embodiment may be a top-emission organic EL element. When the organic EL element is a bottom-emission organic EL element, it is preferable that the anode is a light-transmitting electrode having light transparency, and the cathode is a light-reflective electrode having light reflectivity. When the organic EL element is a top-emission organic EL element, it is preferable that the anode is a light-reflective electrode having light reflectivity, and the cathode is a light-transmitting electrode having light transparency.
[0571] (Capping Layer) When the organic EL element is a top-emission type, the organic EL element usually has a capping layer on the cathode. The capping layer may contain, for example, at least one compound selected from the group consisting of polymer compounds, metal oxides, metal fluorides, metal borides, silicon nitride, and silicon compounds (such as silicon oxide). The capping layer may also contain, for example, at least one compound selected from the group consisting of aromatic amine derivatives, anthracene derivatives, pyrene derivatives, fluorene derivatives, or dibenzofuran derivatives. A laminate obtained by stacking layers containing these substances can also be used as the capping layer.
[0572] (Hole Injection Layer) The hole injection layer is a layer containing a substance with high hole injection properties, such as molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, or manganese oxide. Furthermore, examples of the material with high hole injection properties include low-molecular-weight organic 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), and 1, Examples of the aromatic amine compound include 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), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1). Furthermore, a polymer compound (such as an oligomer, dendrimer, or polymer) can also be used as the substance with high hole injection properties. Examples of such polymer compounds include poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviation: PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD).Furthermore, polymer compounds to which an acid has been added, such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) and polyaniline / poly(styrenesulfonic acid) (PAni / PSS), can also be used.
[0573] (Hole Transport Layer) The hole transport layer is a layer containing a substance with high hole transport properties. For the hole transport layer, an aromatic amine compound, a carbazole derivative, an anthracene derivative, or the like can be used. Specifically, 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: NPB), Examples of aromatic amine compounds that can be used include 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 substances mentioned here are mainly 10 -6 cm 2 The hole-transporting layer may be a material having a hole mobility of 1 / Vs or more. Carbazole derivatives such as CBP, CzPA, and PCzPA, or anthracene derivatives such as t-BuDNA, DNA, and DPAnth may be used for the hole-transporting layer. Polymer compounds such as poly(N-vinylcarbazole) (abbreviation: PVK) and poly(4-vinyltriphenylamine) (abbreviation: PVTPA) may also be used. However, other materials may also be used as long as they have a higher hole-transporting property than electron-transporting property. The layer containing the material having a high hole-transporting property may be a single layer or a layer in which two or more layers made of the above-mentioned materials are stacked.
[0574] (Electron Transport Layer) The electron transport layer is a layer containing a substance with high electron transport properties. For the electron transport layer, 1) metal complexes such as aluminum complexes, beryllium complexes, and zinc complexes, 2) heteroaromatic compounds such as imidazole derivatives, benzimidazole derivatives, azine derivatives, carbazole derivatives, and phenanthroline derivatives, and 3) polymer compounds can be used. Specifically, low-molecular organic compounds such as Alq and tris(4-methyl-8-quinolinolato)aluminum (abbreviated as Almq) can be used. 3 ), bis(10-hydroxybenzo[h]quinolinato)beryllium (abbreviation: BeBq 2 ), BAlq, Znq, ZnPBO, ZnBTZ, and other metal complexes can be used. In addition to metal complexes, 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: OXD-8), 1,3-bis[5-(ptert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-9 ... Heteroaromatic compounds such as 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) can also be used. The substances mentioned here are mainly 10 -6 cm 2 / Vs or more. Note that other substances may be used as the electron-transporting layer as long as they have a higher electron-transporting property than a hole-transporting property. The electron-transporting layer may be a single layer or a stack of two or more layers made of the above-mentioned substances. A polymer compound may also be used for the electron-transporting layer. For example, 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), or the like may be used.
[0575] (Electron Injection Layer) The electron injection layer is a layer containing a substance with high electron injection properties. Examples of the electron injection layer include lithium (Li), cesium (Cs), calcium (Ca), lithium fluoride (LiF), cesium fluoride (CsF), and calcium fluoride (CaF 2Alkali metals, alkaline earth metals, or compounds thereof, such as lithium oxide (LiOx), may be used. Alternatively, a material having electron transport properties containing an alkali metal, alkaline earth metal, or compound thereof, such as magnesium (Mg) in Alq, may be used. In this case, electron injection from the cathode can be performed more efficiently. Alternatively, a composite material containing an organic compound and an electron donor (donor) may be used for the electron injection layer. Such composite materials have excellent electron injection and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material that is excellent at transporting the generated electrons. Specifically, the above-mentioned materials constituting the electron transport layer (e.g., metal complexes and heteroaromatic compounds) may be used. The electron donor may be any material that exhibits electron donating properties to the organic compound. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferred, such as lithium, cesium, magnesium, calcium, erbium, and ytterbium. In addition, alkali metal oxides and alkaline earth metal oxides are preferred, such as lithium oxide, calcium oxide, and barium oxide. Lewis bases such as magnesium oxide can also be used. Organic compounds such as tetrathiafulvalene (abbreviated as TTF) can also be used.
[0576] (Layer Formation Method) The method for forming each layer of the organic EL element according to any of the above-described embodiments is not limited to those specifically mentioned above, but may be any known method such as a dry film formation method such as a vacuum deposition method, a sputtering method, a plasma method, or an ion plating method, or a wet film formation method such as a spin coating method, a dipping method, a flow coating method, or an inkjet method.
[0577] (Film Thickness) The film thickness of each organic layer in the organic EL element according to the first embodiment is not limited unless specifically mentioned above. Generally, if the film thickness is too thin, defects such as pinholes are likely to occur, and if the film thickness is too thick, a high applied voltage is required, resulting in poor efficiency. Therefore, the film thickness of each organic layer in the organic EL element is usually preferably in the range of several nm to 1 μm.
[0578] The organic EL element according to the first embodiment can be used in electronic devices such as display devices and light-emitting devices.
[0579] [Second Embodiment] The configuration of an organic EL element according to a second embodiment will be described. In the description of the second embodiment, the same components as those in the first embodiment will be denoted by the same reference numerals or names, and the description thereof will be omitted or simplified. Furthermore, in the second embodiment, for materials and compounds not specifically mentioned, the same materials and compounds as those described in the first embodiment can be used.
[0580] The organic EL device according to the second embodiment differs from the organic EL device according to the first embodiment in that the light-emitting layer contains the second compound, the third compound, and the fourth compound, but does not contain the first compound. The other features are the same as those of the first embodiment. The third compound and the fourth compound are preferably host materials, and the second compound is preferably a dopant material. In the second embodiment, the light-emitting layer preferably does not contain a phosphorescent metal complex, and preferably does not contain any metal complex other than the phosphorescent metal complex.
[0581] (Second Compound) As the second compound, the second compound described in the first embodiment can be used. The second compound is a thermally activated delayed fluorescent compound.
[0582] (Third Compound and Fourth Compound) The third compound may be the third compound described in the first embodiment. The fourth compound may be the fourth compound described in the first embodiment.
[0583] (Relationship between the second compound, the third compound, and the fourth compound in the light-emitting layer) In the organic EL device according to the second embodiment, the singlet energy S 1 (M2) and the singlet energy S of the third compound 1 In the organic EL element according to the second embodiment, it is preferable that the energy gap T 77K(M3) is the energy gap T at 77 [K] of the second compound 77K It is preferable that it is larger than (M2).
[0584] In the organic EL element according to the second embodiment, it is preferable that the second compound and the fourth compound satisfy the above-mentioned formula (Formula 6). In the organic EL element according to the second embodiment, the energy gap T 77K (M4) is the energy gap T at 77 [K] of the second compound 77K It is preferable that it is larger than (M2).
[0585] FIG. 6 is a diagram illustrating the principle of light emission according to the second embodiment. In FIG. 6, S0 represents the ground state. S1(M2) represents the lowest excited singlet state of the second compound, and T1(M2) represents the lowest excited triplet state of the second compound. S1(M3) represents the lowest excited singlet state of the third compound, and T1(M3) represents the lowest excited triplet state of the third compound. S1(M4) represents the lowest excited singlet state of the third compound, and T1(M4) represents the lowest excited triplet state of the fourth compound. As shown in FIG. 6, when a compound with a small ΔST(M2) is used as the second compound, the lowest excited triplet state T1(M2) of the second compound can undergo reverse intersystem crossing to the lowest excited singlet state S1(M2) due to thermal energy. By utilizing the reverse intersystem crossing occurring in this second compound, for example, luminescence as shown in (i-1) or (ii-1) below can be observed. (i-1) When the emitting layer does not contain a fluorescent dopant whose lowest excited singlet state S1 is smaller than the lowest excited singlet state S1(M2) of the second compound, luminescence from the lowest excited singlet state S1(M2) of the second compound can be observed. (ii-1) When the emitting layer contains a fluorescent dopant (the first compound in the first embodiment) whose lowest excited singlet state S1 is smaller than the lowest excited singlet state S1(M2) of the second compound, luminescence from the fluorescent dopant can be observed. Note that in the organic EL element of the second embodiment, the luminescence shown in (i-1) above can be observed. In the organic EL element of the first embodiment described above, the luminescence shown in (ii-1) above can be observed.
[0586] (Compound Content in Light-Emitting Layer) In the organic EL element according to the second embodiment, the contents of the second compound, the third compound, and the fourth compound contained in the light-emitting layer are preferably within the following ranges, for example. The content of the second compound in the light-emitting layer is 30% by mass or more and 50% by mass or less. The content of the second compound in the light-emitting layer is preferably 30% by mass or more and 45% by mass or less, and more preferably 30% by mass or more and 40% by mass or less. The total content of the third compound and the fourth compound in the light-emitting layer is preferably 50% by mass or more and 70% by mass or less, more preferably 55% by mass or more and 70% by mass or less, and even more preferably 60% by mass or more and 70% by mass or less. The upper limit of the total content of the second compound, the third compound, and the fourth compound in the light-emitting layer is 100% by mass. In the organic EL element according to the second embodiment, the light-emitting layer may contain only one type of second compound, or may contain two or more types of second compounds. The light-emitting layer may contain only one type of third compound or two or more types. The light-emitting layer may contain only one type of fourth compound or two or more types. According to the second embodiment, an organic EL element that emits light with a long lifetime can be realized. The organic EL element according to the second embodiment can be used in electronic devices such as display devices and light-emitting devices.
[0587] Third Embodiment (Electronic Device) An electronic device according to a third embodiment is equipped with the organic EL element according to any one of the above-described embodiments. Examples of the electronic device include a display device and a light-emitting device. Examples of the display device include display components (e.g., an organic EL panel module), a television, a mobile phone, a tablet, and a personal computer. Examples of the light-emitting device include lighting and vehicle lighting fixtures.
[0588] The display device as the electronic device according to the third embodiment is preferably an organic EL display device having organic EL elements as red, green, and blue pixels. In this organic EL display device, the red or green pixel is preferably the organic EL element according to any one of the above-described embodiments. In one aspect of the organic EL display device, the blue pixel may be the organic EL element according to any one of the above-described embodiments.
[0589] [Modifications of the Embodiment] The present invention is not limited to the above-described embodiment, and any modifications and improvements that can achieve the object of the present invention are included in the present invention.
[0590] For example, the number of light-emitting layers is not limited to one, and multiple light-emitting layers may be stacked. When the organic EL element has multiple light-emitting layers, it is sufficient that at least one of the light-emitting layers satisfies the conditions described in the above embodiment. For example, the other light-emitting layers may be fluorescent light-emitting layers or phosphorescent light-emitting layers that utilize light emission by electron transition from a triplet excited state directly to the ground state. Furthermore, when the organic EL element has multiple light-emitting layers, these light-emitting layers may be provided adjacent to each other, or the organic EL element may be a so-called tandem organic EL element in which multiple light-emitting units are stacked via an intermediate layer.
[0591] Furthermore, for example, a barrier layer may be provided adjacent to at least one of the anode side and the cathode side of the light-emitting layer. The barrier layer is preferably disposed in contact with the light-emitting layer and blocks at least one of holes, electrons, and excitons. For example, when a barrier layer is disposed in contact with the cathode side of the light-emitting layer, the barrier layer transports electrons and blocks holes from reaching a layer (e.g., an electron transport layer) closer to the cathode than the barrier layer. When the organic EL device includes an electron transport layer, the barrier layer is preferably provided between the light-emitting layer and the electron transport layer. When a barrier layer is disposed in contact with the anode side of the light-emitting layer, the barrier layer transports holes and blocks electrons from reaching a layer (e.g., a hole transport layer) closer to the anode than the barrier layer. When the organic EL device includes a hole transport layer, the barrier layer is preferably provided between the light-emitting layer and the hole transport layer. Furthermore, the barrier layer may be provided adjacent to the light-emitting layer to prevent excitation energy from leaking from the light-emitting layer to its surrounding layers. The blocking layer prevents excitons generated in the light-emitting layer from migrating to layers closer to the electrode than the blocking layer (for example, the electron transport layer and the hole transport layer).The light-emitting layer and the blocking layer are preferably in contact with each other.
[0592] In addition, the specific structure and shape in carrying out the present invention may be other structures within the scope of achieving the object of the present invention.
[0593] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples in any way.
[0594] <Compounds> The structures of the third and fourth compounds used in the production of the organic EL devices according to Examples 1-1 to 1-9 and Examples 2-1 to 2-3 are shown below.
[0595]
[0596] The structures of other compounds used in the production of the organic EL devices according to Examples 1-1 to 1-9, Examples 2-1 to 2-3, Comparative Examples 1-1 to 1-5, and Comparative Examples 2-1 to 2-4 are shown below.
[0597]
[0598]
[0599]
[0600]
[0601] <Preparation of Organic EL Device> An organic EL device was prepared as follows and evaluated.
[0602] Example 1-1 A 25 mm x 75 mm x 1.1 mm thick glass substrate (manufactured by Geomatec Co., Ltd.) with an ITO transparent electrode (anode) was subjected to ultrasonic cleaning in isopropyl alcohol for 5 minutes, followed by UV ozone cleaning for 1 minute. The ITO film thickness was 130 nm. The cleaned glass substrate with transparent electrode lines was attached to a substrate holder in a vacuum deposition apparatus, and first, compound HT-1 and compound HA were co-deposited on the surface on which the transparent electrode lines were formed so as to cover the transparent electrode, forming a hole injection layer with a film thickness of 10 nm. The proportion of compound HT-1 in the hole injection layer was 97% by mass, and the proportion of compound HA was 3% by mass. Next, compound HT-1 was vapor-deposited on the hole injection layer to form a hole transport layer with a film thickness of 90 nm. Next, compound EBL-1 was vapor-deposited on the hole transport layer as a first electron blocking material to form a first electron blocking layer with a film thickness of 25 nm. Next, on the first electron blocking layer, compound EBL-2 was deposited as a second electron blocking material to form a second electron blocking layer with a thickness of 5 nm. Next, on the second electron blocking layer, compound B1 as a third compound (host material), compound A1 as a fourth compound (host material), compound TADF-1 as a second compound (delayed fluorescent compound), and compound GD-1 as a first compound (fluorescent compound) were co-deposited to form an emitting layer with a thickness of 40 nm. In the emitting layer, the proportion of compound B1 was 41.6% by mass, the proportion of compound A1 was 17.8% by mass, the proportion of compound TADF-1 was 40% by mass, and the proportion of compound GD-1 was 0.6% by mass. Next, compound ET-1 was deposited on the emitting layer to form a hole blocking layer with a thickness of 5 nm. Next, compound ET-2 and compound Liq were co-deposited on the hole blocking layer to form an electron transport layer with a thickness of 35 nm. The concentration of the compound ET-2 in the electron transport layer was 50% by mass, and the concentration of the compound Liq was 50% by mass. Liq is an abbreviation for (8-quinolinolato)lithium. Next, ytterbium (Yb) was vapor-deposited on the electron transport layer to form an electron injection layer with a film thickness of 1 nm. Then, metal aluminum (Al) was vapor-deposited on the electron injection layer to form a metal Al cathode with a film thickness of 50 nm.In this manner, an organic EL device according to Example 1-1 was fabricated. The device configuration of the organic EL device according to Example 1-1 is shown in outline below: ITO(130) / HT-1:HA(10,97%:3%) / HT-1(90) / EBL-1(25) / EBL-2(5) / B1:A1:TADF-1:GD-1(40,41.6%:17.8%:40%:0.6%) / ET-1(5) / ET-2:Liq(35,50%:50%) / Yb(1) / Al(50). Note that in the device configuration, the numbers in parentheses indicate the film thickness (unit: nm). Similarly, in the above element configuration, the figures expressed in percentages in parentheses (97%:3%) indicate the proportions (mass%) of Compound HT-1 and Compound HA in the hole injection layer, the figures expressed in percentages (41.6%:17.8%:40%:0.6%) indicate the proportions (mass%) of Compound B1, Compound A1, Compound TADF-1, and Compound GD-1 in the light-emitting layer, and the figures expressed in percentages (50%:50%) indicate the proportions (mass%) of Compound ET-2 and Liq in the electron transport layer.
[0603] Examples 1-2 to 1-9 The organic EL elements of Examples 1-2 to 1-9 were fabricated in the same manner as in Example 1-1, except that the light-emitting layer (types and contents of compounds) in Example 1-1 was replaced with the light-emitting layer (types and contents of compounds) shown in Table 1.
[0604] (Comparative Examples 1-1 to 1-5) The organic EL elements of Comparative Examples 1-1 to 1-5 were fabricated in the same manner as in Example 1-1, except that the light-emitting layer (type and content of compound) in Example 1-1 was replaced with the light-emitting layer (type and content of compound) shown in Table 1. The light-emitting layer of Comparative Example 1-1 did not contain the third compound. The light-emitting layers of Comparative Examples 1-2 to 1-4 did not contain the fourth compound.
[0605] Examples 2-1 to 2-3 The organic EL elements of Examples 2-1 to 2-3 were fabricated in the same manner as in Example 1-1, except that the light-emitting layer (types and contents of compounds) in Example 1-1 was replaced with the light-emitting layer (types and contents of compounds) shown in Table 2.
[0606] (Comparative Examples 2-1 to 2-4) The organic EL elements of Comparative Examples 2-1 to 2-4 were fabricated in the same manner as in Example 1-1, except that the light-emitting layer (type and content of compound) in Example 1-1 was replaced with the light-emitting layer (type and content of compound) shown in Table 2. The light-emitting layer of Comparative Example 2-1 did not contain the third compound. The light-emitting layers of Comparative Examples 2-2 and 2-3 did not contain the fourth compound.
[0607] <Evaluation of Organic EL Device> The fabricated organic EL device was evaluated as follows. The evaluation results are shown in Tables 1 and 2.
[0608] (CIE 1931 chromaticity) The current density of the organic EL element is 10 mA / cm 2 The spectral radiance spectrum when a voltage was applied to the element so that the spectral radiance spectrum was measured using a spectroradiometer CS-2000 (manufactured by Konica Minolta, Inc.) CIE x and CIE y were calculated from the obtained spectral radiance spectrum.
[0609] (Maximum peak wavelength λ EL The organic EL device thus fabricated was subjected to a current density of 10.00 mA / cm 2 The spectral radiance spectrum when a voltage was applied so that the maximum peak wavelength λ EL (unit: nm) was determined.
[0610] (Lifespan LT95) The fabricated organic EL element was subjected to a current density of 50 mA / cm 2 A voltage was applied so that the voltage was 0.05 V, and the time (LT95 (unit: hours)) until the luminance reached 95% of the initial luminance was measured as the lifespan. The luminance was measured using a spectroradiometer CS-2000 (manufactured by Konica Minolta, Inc.). Tables 1 and 2 show the "LT95 (relative value)" (unit: %). The "LT95 (relative value)" of Examples 1-1 to 1-9 and Comparative Examples 1-1 to 1-5 was calculated based on the measured LT95 value of each example and the following mathematical formula (Math 1X). LT95 (relative value) = (LT95 of each example / LT95 of Comparative Example 1-1) × 100 (Math 1X)
[0611] The "LT95 (relative value)" of Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-4 was calculated based on the measured LT95 value of each example and the following formula (2X): LT95 (relative value) = (LT95 of each example / LT95 of Comparative Example 2-1) × 100 (2X)
[0612]
[0613]
[0614] As shown in Table 1, Examples 1-1 to 1-9, which used two host materials (a third compound and a fourth compound) satisfying the mathematical formulae (1) to (3), emitted light with a longer lifetime than Comparative Example 1-5, which used two host materials not satisfying the mathematical formula (1), and Comparative Examples 1-1 to 1-4, which used only one host material. As shown in Table 2, Examples 2-1 to 2-3, which used two host materials (a third compound and a fourth compound) satisfying the mathematical formulae (1) to (3), emitted light with a longer lifetime than Comparative Example 2-4, which used two host materials not satisfying the mathematical formula (1), and Comparative Examples 2-1 to 2-3, which used only one host material.
[0615] <Evaluation of Compounds> The compounds were evaluated as follows. The evaluation results are shown in Tables 1 to 3.
[0616] (Electron Mobility) Electron mobility was measured by impedance measurement using a mobility evaluation device fabricated according to the following procedure. A compound, Target, for measuring electron mobility, was vapor-deposited on a glass substrate with an aluminum electrode (anode) so as to cover the aluminum electrode, forming a measurement target layer. An electron transport layer was formed on this measurement target layer by vapor-depositing the following compound, ET-A. An electron injection layer was formed on this electron transport layer by vapor-depositing LiF. A metal cathode was formed on this electron injection layer by vapor-depositing metallic aluminum (Al). The configuration of the mobility evaluation device described above is shown in simplified form as follows: Glass / Al(50) / Target(200) / ET-A(10) / LiF(1) / Al(50). The numbers in parentheses indicate film thicknesses (nm).
[0617]
[0618] The electron mobility evaluation element was placed in an impedance measurement device, and impedance measurements were performed. The impedance measurements were performed by sweeping the measurement frequency from 1 Hz to 1 MHz. A DC voltage V was applied to the element simultaneously with an AC amplitude of 0.1 V. From the measured impedance Z, the modulus M was calculated using the relationship of the following calculation formula (C1). Calculation formula (C1): M = jωZ. In the above calculation formula (C1), j is an imaginary unit whose square is -1, and ω is the angular frequency [rad / s]. In a Bode plot with the imaginary part of the modulus M on the vertical axis and frequency [Hz] on the horizontal axis, the electrical time constant τ of the mobility evaluation element was calculated from the frequency fmax showing the peak using the following calculation formula (C2): Calculation formula (C2): τ = 1 / (2πfmax). In the above calculation formula (C2), π is the symbol representing pi. Using the above τ, the electron mobility μE was calculated from the relationship of the following calculation formula (C3-1): Calculation formula (C3-1): μe=d 2 / (Vτ) In the above formula (C3-1), d is the total film thickness of the organic thin films that constitute the device, and in the case of the device configuration for evaluating the electron mobility, d=210 [nm].
[0619] (Ionization potential Ip and energy level HOMO of highest occupied molecular orbital) The ionization potential and energy level HOMO of the highest occupied molecular orbital of a compound were measured under atmospheric conditions using a photoelectron spectrometer (manufactured by Riken Keiki Co., Ltd., "AC-3"). Specifically, the ionization potential and energy level HOMO of the highest occupied molecular orbital of a compound were measured by irradiating the material with light and measuring the amount of electrons generated by charge separation during the irradiation. The ionization potential may be expressed as Ip. The value of the energy level HOMO of the highest occupied molecular orbital corresponds to the value of the ionization potential with a negative sign.
[0620] (The lowest excited singlet energy S 1 ) The lowest excited singlet energy S of the compound to be measured 1 was measured by the solution method described above.
[0621] (Maximum Peak Wavelength λ of Compound) The maximum peak wavelength λ of a compound was measured by the following method. A 5 μmol / L toluene solution of the compound to be measured was prepared and placed in a quartz cell, and the emission spectrum (vertical axis: emission intensity, horizontal axis: wavelength) of this sample was measured at room temperature (300 K). In this example, the emission spectrum was measured using a spectrofluorometer (device name: F-7000) manufactured by Hitachi High-Tech Science Corporation. Note that the emission spectrum measuring device is not limited to the device used here. In the emission spectrum, the peak wavelength at which the emission intensity is maximum was defined as the maximum peak wavelength λ.
[0622] (Delayed Fluorescence of Compound) Delayed fluorescence was confirmed by measuring transient PL using the apparatus shown in Figure 3. The compound TADF-1 was dissolved in toluene to prepare a dilute solution with an absorbance of 0.05 or less at the excitation wavelength to eliminate the contribution of self-absorption. To prevent quenching by oxygen, the sample solution was frozen and degassed, then sealed in a capped cell under an argon atmosphere to obtain an oxygen-free sample solution saturated with argon. The fluorescence spectrum of the sample solution was measured using a spectrofluorometer FP-8600 (manufactured by JASCO Corporation), and the fluorescence spectrum of an ethanol solution of 9,10-diphenylanthracene was also measured under the same conditions. The total fluorescence quantum yield was calculated using the fluorescence area intensities of both spectra according to equation (1) in Morris et al. J. Phys. Chem. 80 (1976) 969. After being excited by pulsed light (light irradiated from a pulsed laser) having a wavelength absorbed by the compound TADF-1, prompt luminescence (immediate luminescence) is observed immediately from the excited state, and delay luminescence (delayed luminescence) is not observed immediately after the excitation but is observed later. In this example, delayed fluorescence means that the amount of delay luminescence (delayed luminescence) is 5% or more of the amount of prompt luminescence (immediate luminescence). Specifically, the amount of prompt luminescence (immediate luminescence) is X P The amount of delayed light emission is set to X D When this is done, X D / X PThis means that the value of X is 0.05 or more. The amounts of prompt luminescence and delay luminescence and their ratio can be determined by a method similar to that described in "Nature 492, 234-238, 2012" (Reference 1). The apparatus used to calculate the amounts of prompt luminescence and delay luminescence is not limited to the apparatus described in Reference 1 or the apparatus shown in Figure 3. Compound TADF-2 was also measured in the same manner as compound TADF-1. It was confirmed that the amount of delay luminescence (delayed luminescence) was 5% or more of the amount of prompt luminescence (immediate luminescence) for compounds TADF-1 and TADF-2. Specifically, for compounds TADF-1 and TADF-2, X D / X P The value was 0.05 or more.
[0623] (energy gap T 77K and ΔST) Energy gap T of the compound to be measured 77K is the energy gap T described in the above "Relationship between triplet energy and energy gap at 77 [K]" 77K The energy gap T 77K and the above-mentioned lowest excited singlet energy S 1 The value of "<0.01" in the table indicates that ΔST is less than 0.01 eV.
[0624]
[0625] DESCRIPTION OF SYMBOLS 1, 1A...organic electroluminescence element, 2...substrate, 3...anode, 4...cathode, 5...light-emitting layer, 6...hole injection layer, 7, 7A...hole transport region, 8...electron transport region, 10, 10A...organic layer, 71...hole transport layer, 72...first hole blocking layer, 73...second hole blocking layer, 74...hole injection layer, 75...third hole blocking layer, 81...electron transport layer, 82...electron injection layer.
Claims
1. An organic electroluminescence device comprising an anode, a cathode, and an emitting layer between the anode and the cathode, wherein the emitting layer contains a first compound, a second compound, a third compound, and a fourth compound, the first compound, the second compound, the third compound, and the fourth compound being different from one another, the first compound being a fluorescent compound, and the second compound being a delayed fluorescent compound, the content of the second compound in the emitting layer being 30% by mass or more and 50% by mass or less, and the third compound and the fourth compound satisfying the following mathematical formulas (Mathematical Formula 1), (Mathematical Formula 2), and (Mathematical Formula 3). (Mathematical Formula 1): 0.08 eV≦|HOMO(M3)−HOMO(M4)|≦0.22 eV (Mathematical Formula 2): μE(M3)≦5.0×10 -7 cm 2 / Vs (Math. 3): μE (M4)≦5.0×10 -7 cm 2 / Vs (HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound, μE(M3) is the electron mobility of the third compound, and μE(M4) is the electron mobility of the fourth compound).
2. The organic electroluminescence device according to claim 1, wherein the first compound and the second compound satisfy the following formula (Formula 4): S 1 (M2) > S 1 (M1) (S 1 (M1) is the lowest excited singlet energy of the first compound, and S 1 (M2) is the lowest excited singlet energy of the second compound.
3. The organic electroluminescence device according to claim 1 or 2, wherein the second compound and the third compound satisfy the following formula (Formula 5): (Formula 5): S 1 (M3) > S 1 (M2) (S 1 (M2) is the lowest excited singlet energy of the second compound, and S 1 (M3) is the lowest excited singlet energy of the third compound.
4. The organic electroluminescence device according to any one of claims 1 to 3, wherein the second compound and the fourth compound satisfy the following formula (Formula 6): (Formula 6): S 1 (M4) > S 1 (M2) (S 1 (M2) is the lowest excited singlet energy of the second compound, and S 1 (M4) is the lowest excited singlet energy of the fourth compound.
5. The organic electroluminescence device according to any one of claims 1 to 4, wherein the content of the second compound in the light-emitting layer is 35% by mass or more and 45% by mass or less.
6. The organic electroluminescence device according to any one of claims 1 to 5, wherein the content of the second compound in the light-emitting layer is 35% by mass or more and 40% by mass or less.
7. The organic electroluminescence device according to any one of claims 1 to 6, wherein the third compound and the fourth compound satisfy the following mathematical formula (Mathematical Formula 11): 0.08 eV≦|HOMO(M3)−HOMO(M4)|≦0.12 eV (HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, and HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound).
8. The organic electroluminescence device according to any one of claims 1 to 7, wherein the third compound and the fourth compound satisfy the following mathematical formula (Mathematical Formula 14): |HOMO(M4)|>|HOMO(M3)| (HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, and HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound).
9. The organic electroluminescence device according to any one of claims 1 to 8, wherein the second compound, the third compound, and the fourth compound satisfy the following mathematical formula (Mathematical Formula 16): |HOMO(M2)|>|HOMO(M4)|>|HOMO(M3)| (HOMO(M2) is the energy level of the highest occupied molecular orbital of the second compound, HOMO(M3) is the energy level of the highest occupied molecular orbital of the third compound, and HOMO(M4) is the energy level of the highest occupied molecular orbital of the fourth compound.) 10. The organic electroluminescence device according to any one of claims 1 to 9, wherein the first compound, the second compound, the third compound, and the fourth compound are contained in a single light-emitting layer.
11. An organic electroluminescence device according to any one of claims 1 to 10, wherein the mass content of one of the third compound and the fourth compound in the light-emitting layer is greater than the mass content of the second compound in the light-emitting layer, and the mass content of the other of the third compound and the fourth compound in the light-emitting layer is smaller than the mass content of the second compound in the light-emitting layer.
12. The organic electroluminescence device according to any one of claims 1 to 11, wherein the mass content of the fourth compound in the light-emitting layer is greater than the mass content of the second compound in the light-emitting layer.
13. The organic electroluminescence device according to any one of claims 1 to 12, wherein the mass content of the third compound in the light-emitting layer is smaller than the mass content of the second compound in the light-emitting layer.
14. The organic electroluminescence device according to any one of claims 1 to 10, wherein the mass content of the third compound in the light-emitting layer is smaller than the mass content of the second compound in the light-emitting layer, and the mass content of the fourth compound in the light-emitting layer is smaller than the mass content of the second compound in the light-emitting layer.
15. The organic electroluminescence device according to any one of claims 1 to 14, wherein the light-emitting layer does not contain a metal complex.
16. The organic electroluminescence device according to any one of claims 1 to 15, wherein the light-emitting layer does not contain a phosphorescent material.
17. The organic electroluminescent device according to any one of claims 1 to 16, comprising a hole transporting region between the anode and the light-emitting layer.
18. The organic electroluminescent device according to any one of claims 1 to 17, comprising an electron transporting region between the cathode and the light-emitting layer.
19. An electronic device equipped with the organic electroluminescence element according to any one of claims 1 to 18.
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