Composition for organic electroluminescent element, organic electroluminescent element and method for manufacturing the same, and display device

Abstract

To provide a composition for manufacturing an organic electroluminescent element that can be manufactured by a wet film-forming method, and that has higher luminous efficiency and a longer driving life than conventional organic electroluminescent elements.SOLUTION: A composition for an organic electroluminescent element includes a compound A satisfying the formula (I) below and a compound B satisfying the formula (II) below, and the compound A and the compound B each have two or more carbazolyl groups. 4.20<NA<5.80 (I). 1.00<NB<2.90 (II). In the formula (I), NA represents the number of nitrogen atoms in compound A per 1,000 molecular weight. In the formula (II), NB represents the number of nitrogen atoms in compound B per 1,000 molecular weight.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a compound that can be used in an organic electroluminescent device (hereinafter, sometimes referred to as "OLED" or "device"). The present invention also relates to an organic electroluminescent device having the compound, a composition containing the compound and an organic solvent, a method for forming a thin film using the composition, and a method for producing an organic electroluminescent device. [Background technology]

[0002] In recent years, organic electroluminescent devices using organic thin films have been developed, replacing those using inorganic materials as thin-film electroluminescent devices. Organic electroluminescent devices (OLEDs) typically have a hole injection layer, hole transport layer, organic light-emitting layer, electron transport layer, and other layers between an anode and a cathode. Materials suitable for each of these layers are being developed, and development of light-emitting colors such as red, green, and blue is progressing. Research is also underway on solution-based OLEDs, which have higher material utilization efficiency and lower manufacturing costs compared to conventional vapor deposition-based OLEDs.

[0003] For coating-type OLEDs, there is a demand for longer device life and lower power consumption. There are various factors that affect device life and power consumption improvement. For example, the heat resistance and crystallinity of the materials that make up the device are thought to have a major impact on device life.

[0004] In order to manufacture organic electroluminescent devices using a wet film-forming method, all materials used must be soluble in organic solvents and can be used as ink. If the materials used are poorly soluble, they may deteriorate before use because they require operations such as long-term heating. If the solution cannot be maintained in a homogeneous state for a long period of time, the materials will precipitate from the solution, making it impossible to form a film using an inkjet device or the like. Materials used in wet film formation methods are required to have solubility in two senses: they must dissolve quickly in organic solvents, and once dissolved, they must remain homogeneous without precipitating.

[0005] Patent Document 1 discloses an organic electroluminescent device in which an emitting layer containing a compound having a triazine skeleton as shown below is formed by a wet film-forming method, and attempts have been made to provide a composition for forming an emitting layer for an organic electroluminescent device that has high storage stability and excellent solubility in organic solvents.

[0006] [ka]

[0007] Patent Document 2 discloses an organic electroluminescent device in which an emitting layer containing a compound having a biscarbazole skeleton as shown below is formed by a vacuum deposition method, and attempts are made to improve the driving voltage and efficiency.

[0008] [ka]

[0009] Patent Document 3 discloses an organic electroluminescent device in which an emitting layer containing a compound having a biscarbazole skeleton as shown below is formed by a wet film-forming method, and attempts are made to provide a composition for forming an emitting layer for an organic electroluminescent device that has excellent solubility in organic solvents.

[0010] [ka] [Prior art documents] [Patent documents]

[0011] [Patent Document 1] International Publication No. 2012 / 096263 [Patent Document 2] Japan Special Publication No. 2019-525463 [Patent Document 3] Japanese Patent Application Publication No. 2020-105152 Summary of the Invention [Problem to be solved by the invention]

[0012] However, the above-mentioned prior art cannot be said to be sufficient in terms of the performance of organic electroluminescent elements for display applications, and there has been a demand for further improvements in the luminous efficiency and driving life of organic electroluminescent elements in which the luminescent layer is formed by a wet film-forming method.

[0013] An object of the present invention is to provide a composition for producing an organic electroluminescent device that can be produced by a wet film-forming method and has higher luminous efficiency and longer operating life than conventional organic electroluminescent devices. [Means for solving the problem]

[0014] As a result of extensive investigations, the present inventors have found that an organic electroluminescent device having an emitting layer formed by a wet film formation method using a composition containing compound A satisfying a specific formula and compound B satisfying a specific formula has high luminous efficiency and a long operating life, and have arrived at the present invention.

[0015] The gist of the present invention is as follows.

[0016] Aspect 1 of the present invention is A composition for an organic electroluminescent device, Compound A satisfying the following formula (I); and a compound B satisfying the following formula (II): The present invention relates to a composition, wherein the compound A and the compound B each have two or more carbazolyl groups. 4.20 <N A <5.80 Formula (I) 1.00 <N B <2.90 Formula (II) In formula (I), N A represents the number of nitrogen atoms in compound A per 1000 molecular weight. In formula (II), N B represents the number of nitrogen atoms in compound B per 1000 molecular weight.

[0017] A second aspect of the present invention relates to the composition of the first aspect, The present invention relates to a composition, wherein the compound A is represented by the following formula (1):

[0018] [ka]

[0019] (In formula (1), W 11 , W 12 and W 13 each independently represents CH or N, W 11 , W 12 and W 13 at least one of which is a nitrogen atom, Xa 11 , Ya 11 , and Za 11 each independently represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, Xa 12 , Ya 12 and Za 12 each independently represents a hydrogen atom, an optionally substituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, or an optionally substituted monovalent aromatic heterocyclic group having 3 to 30 carbon atoms, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or greater, If g11 is an integer greater than or equal to 2, multiple Xa 11 may be the same or different, If h11 is an integer greater than or equal to 2, multiple Ya 11 may be the same or different, If j11 is an integer greater than or equal to 2, multiple Za 11 may be the same or different, R 11 represents a hydrogen atom or a substituent, and four R 11 may be the same or different, However, if g11, h11, or j11 is 0, the corresponding Xa 12 , Ya 12 , Za 12 is not a hydrogen atom.)

[0020] A third aspect of the present invention relates to the composition of the second aspect, The present invention relates to a composition in which the compound represented by formula (1) is represented by the following formula (1-1):

[0021] [ka]

[0022] (In formula (1-1), W 11 , W 12 and W 13 each independently represents —CH or a nitrogen atom; W 11 , W 12 and W 13 at least one of which is a nitrogen atom, Xa 11 , Ya 11 , and Za 11 each independently represents an optionally substituted 1,3-phenylene group or an optionally substituted 1,4-phenylene group, Ya 11 and Za 11 at least one of is an optionally substituted 1,3-phenylene group, Xa 12 represents an optionally substituted phenyl group, Ya 12 and Za 12 each independently represents an N-carbazolyl group which may have a substituent, f11 is 1 or 2, g11 is an integer from 0 to 5, h11 is an integer from 0 to 5, j11 is an integer between 0 and 5, R 11 each independently represents a hydrogen atom or a substituent.

[0023] A fourth aspect of the present invention relates to the composition of the third aspect, Ya in the formula (1-1) 11 At least one of Za is a 1,3-phenylene group, 11 at least one of which is a 1,3-phenylene group.

[0024] A fifth aspect of the present invention relates to the composition of the third or fourth aspect, Xa in the formula (1-1) 11 at least one of which is a 1,3-phenylene group.

[0025] A sixth aspect of the present invention relates to a composition comprising any one of the first to fifth aspects, The present invention relates to a composition, wherein the compound B is represented by the following formula (240) or the following formula (241).

[0026] [ka]

[0027] (In formula (240), Ar 611 , Ar 612 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 611 , R 612 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. G represents a single bond or a divalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. n 611 , n 612 are each independently an integer of 0 to 4.

[0028] [ka]

[0029] (In formula (241), Ar 613 ~Ar 615 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 613 , R 614 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. Each G independently represents a single bond or a divalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. n 613 , n 614 are each independently an integer of 0 to 4.

[0030] A seventh aspect of the present invention relates to a composition according to any one of the first to sixth aspects, The present invention relates to a composition, wherein the compound B is represented by the following formula (240-1) or the following formula (241-1).

[0031] [ka]

[0032] (In formula (240-1), Ar 611 , Ar 612 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 611 , R 612 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent.

[0033] [ka]

[0034] (In formula (241-1), Ar 613 ~Ar 615each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 613 , R 614 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent.

[0035] Aspect 8 of the present invention relates to the composition of aspect 6, wherein Ar in the formula (240) and formula (241) 611 ~Ar 615 are each independently a monovalent group in which a plurality of benzene rings, which may have a substituent, are bonded in a linear or branched manner.

[0036] A ninth aspect of the present invention relates to the composition of the sixth or eighth aspect, R in the formula (240) and the formula (241) 611 ~R 614 are each independently a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent.

[0037] A tenth aspect of the present invention relates to a composition according to any one of the first to ninth aspects, The composition further comprises a light-emitting material.

[0038] An eleventh aspect of the present invention is the composition of the tenth aspect, The present invention relates to a composition comprising, as the light-emitting material, at least one compound represented by the following formula (3):

[0039] [ka]

[0040] [In formula (3), Ring A1 represents an aromatic hydrocarbon structure which may have a substituent or an aromatic heterocyclic structure which may have a substituent. Ring A2 represents an aromatic heterocyclic structure which may have a substituent. R 201 , R202 are each independently a structure represented by formula (b), and "*" indicates the bonding position to ring A1 or ring A2. 201 , R 202 may be the same or different, and R 201 , R 202 When there are a plurality of each of the groups, they may be the same or different. Ar 201 , Ar 203 each independently represents an aromatic hydrocarbon structure which may have a substituent, or an aromatic heterocyclic structure which may have a substituent. Ar 202 represents an aromatic hydrocarbon structure which may have a substituent, an aromatic heterocyclic structure which may have a substituent, or an aliphatic hydrocarbon structure which may have a substituent. The substituents bonded to ring A1 may bond to each other, the substituents bonded to ring A2 may bond to each other, or the substituents bonded to ring A1 and the substituents bonded to ring A2 may bond to each other to form a ring. B 201 -L 200 -B 202 represents an anionic bidentate ligand. 201 and B 202 Each of L independently represents a carbon atom, an oxygen atom, or a nitrogen atom, and these atoms may be atoms constituting a ring. 200 is a single bond or B 201 and B 202 represents the atomic group that together with B constitutes a bidentate ligand. 201 -L 200 -B 202 When there are multiple groups, they may be the same or different. In addition, in formula (3) and formula (b), i1 and i2 each independently represent an integer of 0 to 12, i3 is Ar 202 represents an integer greater than or equal to 0, with the upper limit being the number that can be replaced by i4 is Ar 201 represents an integer greater than or equal to 0, with the upper limit being the number that can be replaced by k1 and k2 each independently represent an integer of 0 or greater, the upper limit of which is the number of groups that can be substituted on ring A1 and ring A2; z represents an integer of 1 to 3. M represents a metal atom selected from Groups 7 to 11 of the periodic table.

[0041] A twelfth aspect of the present invention relates to a composition according to any one of the first to eleventh aspects, The present invention further relates to a composition comprising at least one compound represented by the following formula (260):

[0042] [ka]

[0043] (In formula (260), Ar 21 ~Ar 35 each independently represents a hydrogen atom, a phenyl group which may have a substituent, or a monovalent group in which 2 to 10 phenyl groups which may have a substituent are linked in an unbranched or branched manner.

[0044] A thirteenth aspect of the present invention relates to the composition of the twelfth aspect, In the formula (260), Ar 21 , Ar 25 , Ar 26 , Ar 30 , Ar 31 and Ar 35 is a hydrogen atom, Ar 22 ~Ar 24 , Ar 27 ~Ar 29 , and Ar 32 ~Ar 34 each independently represents a hydrogen atom, a phenyl group which may have a substituent, or a structure selected from the following formulas (261-1) to (261-9), each of which may have a substituent:

[0045] [ka]

[0046] (In formulas (261-1) to (261-9), * represents the bonding position to the benzene ring in formula (260).)

[0047] A fourteenth aspect of the present invention relates to a composition according to any one of the first to thirteenth aspects, The composition further comprises an organic solvent.

[0048] A fifteenth aspect of the present invention is The present invention relates to a method for producing an organic electroluminescent device, comprising the step of forming a light-emitting layer by a wet film-forming method using the composition of any one of Aspects 1 to 14.

[0049] A sixteenth aspect of the present invention is The present invention relates to an organic electroluminescent device having a light-emitting layer formed using the composition of any one of Embodiments 1 to 14.

[0050] A seventeenth aspect of the present invention is The present invention relates to a display device having the organic electroluminescent device of embodiment 16. [Effects of the Invention]

[0051] According to the present invention, it is possible to provide a composition for producing an organic electroluminescent device having higher luminous efficiency and longer operating life than conventional ones.

[0052] The present invention can provide an organic electroluminescent device having the composition, a composition containing the composition and an organic solvent, a method for forming a thin film, and a method for producing an organic electroluminescent device. [Brief explanation of the drawings]

[0053] [Figure 1] FIG. 1 is a cross-sectional view showing a structural example of an organic electroluminescent device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0054] The following describes in detail the embodiments of the present invention, but the present invention is not limited to the following embodiments and can be practiced in various modifications within the scope of the gist. In addition, when the expression "to" is used in this specification, it is used as an expression including the numerical values ​​or physical property values ​​before and after it.

[0055] In the present invention, the phrase "optionally having a substituent" means that the group may have one or more substituents.

[0056] In this specification, the terms "(hetero)aralkyl group," "(hetero)aryloxy group," and "(hetero)aryl group" refer to an aralkyl group that may contain a heteroatom, an aryloxy group that may contain a heteroatom, and an aryl group that may contain a heteroatom, respectively. "May contain a heteroatom" means that one or more carbon atoms forming the aryl skeleton in the main skeleton of the aralkyl group, aryloxy group, or aryl group are substituted with heteroatoms. Examples of heteroatoms include nitrogen atoms, oxygen atoms, sulfur atoms, phosphorus atoms, and silicon atoms. Among these, nitrogen atoms are preferred from the viewpoint of durability. In addition, in this specification, the term "(hetero)aryl group" is used to mean a monocyclic group, a 2- to 4-fused ring group, and a group in which a plurality of monocyclic and / or 2- to 4-fused ring groups are linked together. The (hetero)aryl group represents an aryl group which may contain a heteroatom, that is, an aryl group or a heteroaryl group, where an aryl group is an aromatic hydrocarbon group and a heteroaryl group is an aromatic heterocyclic group.

[0057] [Composition] A composition according to an embodiment of the present invention is a composition for an organic electroluminescent device, and comprises a compound A satisfying the following formula (I) and a compound B satisfying the following formula (II), wherein the compound A and the compound B each have two or more carbazolyl groups: 4.20 <N A <5.80 Formula (I) 1.00 <N B <2.90 Formula (II) In formula (I), N A represents the number of nitrogen atoms in compound A per 1000 molecular weight. In formula (II), N B represents the number of nitrogen atoms in compound B per 1000 molecular weight.

[0058] When compound A satisfies formula (I) and compound B satisfies formula (II), compounds with different polarities are present in the light-emitting layer, resulting in a good charge balance in the light-emitting layer. Furthermore, when compound A and compound B each have two or more carbazolyl groups, the heat resistance of the light-emitting layer is improved. Furthermore, the presence of compounds with different polarities in the light-emitting layer can improve the amorphous nature of the light-emitting layer, inhibiting crystallization in the film, and it is believed that a highly efficient, long-lasting organic electroluminescent device can be obtained.

[0059] Compound A, compound B, and preferred embodiments thereof are as described below.

[0060] [Compound A] Compound A is preferably a compound represented by the following formula (1).

[0061] [ka]

[0062] (In formula (1), W 11 , W 12 and W 13 each independently represents CH or N, W 11 , W 12 and W 13 at least one of which is a nitrogen atom, Xa 11 , Ya 11 , and Za 11 each independently represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, Xa 12 , Ya 12 and Za12 each independently represents a hydrogen atom, an optionally substituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, or an optionally substituted monovalent aromatic heterocyclic group having 3 to 30 carbon atoms, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or greater, If g11 is an integer greater than or equal to 2, multiple Xa 11 may be the same or different, If h11 is an integer greater than or equal to 2, multiple Ya 11 may be the same or different, If j11 is an integer greater than or equal to 2, multiple Za 11 may be the same or different, R 11 represents a hydrogen atom or a substituent, and four R 11 may be the same or different, However, if g11, h11, or j11 is 0, the corresponding Xa 12 , Ya 12 , Za 12 is not a hydrogen atom.)

[0063] The compound represented by the above formula (1) is preferably a charge transport compound, that is, a charge transport host material.

[0064] <W 11 , W 12 , W 13 > W in Equation (1) 11 , W 12 and W 13 each independently represents —CH or a nitrogen atom; W 11 , W 12 and W 13 At least one of them is a nitrogen atom. From the viewpoint of electron transport property and electron durability, at least W 11 is preferably a nitrogen atom, and at least W 11 and W 12 is preferably a nitrogen atom, and W 11 , W12 and W 13 It is more preferable that all of are nitrogen atoms.

[0065] That is, from the viewpoint of improving the electron transport property, W 11 is preferably a nitrogen atom, and W 12 Plus W 12 or W 13 A pyrimidine structure in which one of W is a nitrogen atom is more preferred. 11 , W 12 and W 13 A triazine structure in which all atoms are nitrogen is most preferred.

[0066] <Xa 11 , Ya 11 , Za 11 , Xa 12 , Ya 12 , Za 12 > In formula (1), Xa 11 , Ya 11 , Za 11 is a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, and Xa 12 , Ya 12 , Za 12 When the aromatic hydrocarbon group having 6 to 30 carbon atoms optionally having a substituent is an aromatic hydrocarbon group having 6 to 30 carbon atoms, the aromatic hydrocarbon ring of the aromatic hydrocarbon group having 6 to 30 carbon atoms is preferably a 6-membered monocyclic ring or 2 to 5 condensed rings. Specific examples include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a fluorene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, a fluoranthene ring, and an indenofluorene ring. Among these, a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, or a fluorene ring is preferred, a benzene ring, a naphthalene ring, a phenanthrene ring, or a fluorene ring is more preferred, and a benzene ring, a naphthalene ring, or a fluorene ring is even more preferred. In addition, when g11 is 2 or more, the terminal partial structure, -Xa 11 -Xa 12 , -Ya is a terminal partial structure when h11 is 2 or more. 11 -Ya12 and a terminal partial structure when j11 is 2 or more, -Za 11 -Za 12 may be a spirofluorene structure.

[0067] The compound represented by formula (1) is a terminal partial structure, -Xa 11 -Xa 12 , -Ya is a terminal partial structure when h11 is an integer of 2 or more. 11 -Ya 12 and a terminal partial structure when j11 is an integer of 2 or more, -Za 11 -Za 12 At least one of these is preferably a spirofluorene structure or an N-carbazolyl group.

[0068] In formula (1), Xa 11 , Ya 11 , Za 11 is a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, and Xa 12 , Ya 12 , Za 12When is an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, the aromatic heterocyclic ring of the aromatic heterocyclic group having 3 to 30 carbon atoms is preferably a 5- or 6-membered monocyclic ring or 2 to 5 condensed rings. Specific examples thereof include a furan ring, a benzofuran ring, a dibenzofuran ring, a thiophene ring, a benzothiophene ring, a dibenzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, a carbazole ring, an indolocarbazole ring, an indenocarbazole ring, a pyrroloimidazole ring, a pyrrolopyrazole ring, a pyrrolopyrrole ring, a thienopyrrole ring, a thienothiophene ring, a furopyrrole ring, a furofuran ring, a thienofuran ring, a benzisoxazole ring, a benzisothiazole ring, a benzimidazole ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinoxaline ring, a perimidine ring, a quinazoline ring, and a quinazolinone ring. Among these, a thiophene ring, a pyrrole ring, an imidazole ring, a pyridine ring, a pyrimidine ring, a triazine ring, a quinoline ring, a quinazoline ring, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, an indolocarbazole ring, a phenanthroline ring, or an indenocarbazole ring is preferred, a pyridine ring, a pyrimidine ring, a triazine ring, a quinoline ring, a quinazoline ring, a carbazole ring, an indolocarbazole ring, an indenocarbazole ring, a dibenzofuran ring, or a dibenzothiophene ring is more preferred, and a carbazole ring, an indolocarbazole ring, a dibenzofuran ring, or a dibenzothiophene ring is even more preferred. Xa in formula (1) 11 , Ya 11 , Za 11 , Xa 12 , Ya 12 , and Za 12 In the above, particularly preferred aromatic hydrocarbon rings are a benzene ring, a naphthalene ring, or a phenanthrene ring, and particularly preferred aromatic heterocycles are a carbazole ring, an indolocarbazole ring, a dibenzofuran ring, or a dibenzothiophene ring.

[0069] <g11、h11、j11> g11, h11, and j11 each independently represent an integer of 0 to 6, and at least one of g11, h11, and j11 is an integer of 1 or greater. From the viewpoint of charge transport properties and durability, it is preferred that g11 is an integer of 2 or greater, or that at least one of h11 and j11 is an integer of 3 or greater. In addition, the compound represented by formula (1) has a central W 11 , W 12 and W 13 It is preferable that the compound has a total of 8 to 18 of these rings, including the ring having the following formula, from the viewpoints of charge transportability, durability, and solubility in organic solvents.

[0070] <(Xa 11 ) g11 , (Ya 11 ) h11、 (Za 11 ) j11 > (Xa 11 ) g11 , (Ya 11 ) h11、 and (Za 11 ) j11 From the viewpoint of the solubility and durability of the compound, it is preferable that at least one group selected from the following formula (11), the following formula (12), and the following formula (13) each independently have a partial structure selected from the following formula (11), the following formula (12), and the following formula (13), and when g11 is an integer of 1 or more, (Xa 11 ) g11 , where h11 is an integer greater than or equal to 1 (Ya 11 ) h11、 and j11 is an integer greater than or equal to 1 (Za 11 ) j11 It is more preferable that each independently have a partial structure selected from a partial structure represented by the following formula (11), a partial structure represented by the following formula (12), and a partial structure represented by the following formula (13).

[0071] [ka]

[0072] In each of the above formulas (11) to (13), * indicates the bonding position with the adjacent structure, or Xa 12 , Ya 12 , or Za 12 represents the hydrogen atom when * is a hydrogen atom. At least one of the two * marks represents the bonding position to the adjacent structure. In the following description, * has the same definition unless otherwise specified.

[0073] More preferably, when g11 is an integer of 1 or more, (Xa 11 ) g11 , where h11 is an integer greater than or equal to 1 (Ya 11 ) h11 , and j11 is an integer greater than or equal to 1 (Za 11 ) j11 each independently has a partial structure represented by formula (11) or a partial structure represented by formula (12). More preferably, when g11 is an integer of 1 or more, (Xa 11 ) g11 , where h11 is an integer greater than or equal to 1 (Ya 11 ) h11 , and j11 is an integer greater than or equal to 1 (Za 11 ) j11 each independently has a partial structure represented by formula (11) and a partial structure represented by formula (12).

[0074] The partial structure represented by formula (12) is preferably a partial structure represented by the following formula (12-2).

[0075] [ka]

[0076] The partial structure represented by formula (12) is more preferably a partial structure represented by the following formula (12-3).

[0077] [ka]

[0078] As the partial structure having the partial structure represented by formula (11) and the partial structure represented by formula (12), a partial structure selected from the following formulas (14) to (17) is preferred, which is a structure containing a plurality of structures selected from the partial structure represented by formula (11) and the partial structure represented by formula (12). That is, when g11 is an integer of 1 or more, (Xa 11 ) g11 , where h11 is an integer greater than or equal to 1 (Ya 11 ) h11、 and j11 is an integer greater than or equal to 1 (Za 11 ) j11 each independently has a partial structure selected from the formulas (11) to (13) and the following formulas (14) to (17):

[0079] [ka]

[0080] A structure containing a plurality of structures selected from the partial structure represented by formula (11) and the partial structure represented by formula (12) means, for example, a partial structure represented by formula (14) that can be considered to have one partial structure represented by formula (11) and two partial structures represented by formula (12), as in the following formula (14a):

[0081] [ka]

[0082] More preferably, (Xa 11 ) g11 , (Ya 11 ) h11、 and (Za 11 ) j11 At least one of the groups has at least a partial structure represented by formula (14) or a partial structure represented by formula (15). More preferably, when g11 is an integer of 1 or more, (Xa 11 ) g11 , where h11 is an integer greater than or equal to 1 (Ya 11 ) h11, and j11 is an integer greater than or equal to 1 (Za 11 ) j11 has a partial structure represented by formula (14) or a partial structure represented by formula (15).

[0083] The partial structure represented by formula (14) is preferably a partial structure represented by the following formula (14-2).

[0084] [ka]

[0085] The partial structure represented by formula (14) is more preferably a partial structure represented by the following formula (14-3).

[0086] [ka]

[0087] The partial structure represented by formula (15) is preferably a partial structure represented by the following formula (15-2).

[0088] [ka]

[0089] The partial structure represented by formula (15) is more preferably a partial structure represented by the following formula (15-3).

[0090] [ka]

[0091] The partial structure represented by formula (17) is preferably a partial structure represented by the following formula (17-2).

[0092] [ka]

[0093] (Xa 11 ) g11 , (Ya 11 ) h11、 and (Za 11 ) j11 It is more preferable that at least one of the above has a partial structure represented by the following formula (19) or a partial structure represented by the following formula (20) as a partial structure containing a partial structure represented by formula (13).

[0094] [ka]

[0095] In each of the above formulas (14) to (20), * indicates the bonding position with the adjacent structure, or Xa 12 , Ya 12 , or Za 12 represents the hydrogen atom. At least one of the two * marks represents the bonding position to the adjacent structure.

[0096] Among the partial structures represented by formulas (14) to (20), the partial structure represented by formula (14-3) and the partial structure represented by formula (15-3) are preferred, with formula (14-3) being more preferred.

[0097] -(Xa 11 ) g11 -(Xa 12 ), -(Ya 11 ) h11 -(Ya 12 ), and -(Za 11 ) j11 -(Za 12 ) each independently preferably has a partial structure represented by formula (11), a partial structure represented by formula (12-3), a partial structure represented by formula (14-3), or a partial structure represented by formula (15-3).

[0098] Also, -(Xa 11 ) g11 -(Xa 12 ), -(Ya 11 ) h11 -(Ya12 ), and -(Za 11 ) j11 -(Za 12 ) preferably has any one of partial structures or terminal structures represented by the following formulae (250-1) to (250-10).

[0099] [ka]

[0100] [In the above structure, * indicates the bonding position. 250 represents an aromatic hydrocarbon group having 6 to 20 carbon atoms. 32 represents a substituent. These structures may further have a substituent.]

[0101] The substituents that these structures may have are R 32 is the same as:

[0102] Ar 250 is preferably an aromatic hydrocarbon group having 6 to 20 carbon atoms, more preferably a phenyl group or a biphenyl group, and even more preferably a phenyl group.

[0103] R 32 In a structure having two R 32 may be the same or different. R 32is preferably an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, an arylsilyl group having 6 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms which may be substituted with an alkyl group having 1 to 8 carbon atoms, or a heteroaryl group having 3 to 30 carbon atoms which may be substituted with an alkyl group having 1 to 8 carbon atoms, more preferably an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 40 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or an aryl group having 6 to 30 carbon atoms which may be substituted with an alkyl group having 1 to 8 carbon atoms, and even more preferably an alkyl group having 1 to 8 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, or an aryl group having 6 to 14 carbon atoms which may be substituted with an alkyl group having 1 to 8 carbon atoms.

[0104] <R 11 > R in Equation (1) 11 are each independently a hydrogen atom or a substituent. R is a substituent other than a hydrogen atom. 11 Examples of the substituent Q include groups selected from the substituent group Q described below. R when it is a substituent 11 is preferably an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent. From the viewpoint of improving durability and charge transportability, an aromatic hydrocarbon group which may have a substituent is more preferred. When R is a substituent, 11 When there are a plurality of groups, they may be different from each other.

[0105] The substituents which the aromatic hydrocarbon group having 6 to 30 carbon atoms may have, the substituents which the aromatic heterocyclic group having 3 to 30 carbon atoms may have, and the substituent R 11 The substituent that may be possessed by can be selected from the substituent group Q described below.

[0106] <Molecular weight of compound A> The molecular weight of compound A is usually 5,000 or less, preferably 3,000 or less, more preferably 2,500 or less, particularly preferably 2,000 or less, and most preferably 1,800 or less. The lower limit of the molecular weight of compound A is usually preferably 350 or more, more preferably 400 or more, particularly preferably 500 or more.

[0107] <Specific examples of the compound represented by formula (1)> The compound represented by formula (1) is not particularly limited, but examples thereof include the following compounds.

[0108] [ka]

[0109] [ka]

[0110] [ka]

[0111] [ka]

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] [ka]

[0116] The composition according to the embodiment of the present invention may contain only one type of compound represented by the formula (1), or may contain two or more types.

[0117] [Compound represented by formula (1-1)] In the composition according to the embodiment of the present invention, the compound represented by formula (1) (compound A) is preferably represented by formula (1-1).

[0118] [ka]

[0119] (In formula (1-1), W 11 , W 12 and W 13 each independently represents —CH or a nitrogen atom; W 11 , W 12 and W 13 at least one of which is a nitrogen atom, Xa 11 , Ya 11 , and Za 11 each independently represents an optionally substituted 1,3-phenylene group or an optionally substituted 1,4-phenylene group, Ya 11 and Za 11 at least one of is an optionally substituted 1,3-phenylene group, Xa 12 represents an optionally substituted phenyl group, Ya 12 and Za 12 each independently represents an N-carbazolyl group which may have a substituent, f11 is 1 or 2, g11 is an integer from 0 to 5, h11 is an integer from 0 to 5, j11 is an integer between 0 and 5, R 11each independently represents a hydrogen atom or a substituent.

[0120] <W 11 , W 12 , W 13 > W in formula (1-1) 11 , W 12 and W 13 each independently represents —CH or a nitrogen atom; W 11 , W 12 and W 13 At least one of them is a nitrogen atom. From the viewpoint of electron transport property and electron durability, at least W 11 is preferably a nitrogen atom, and at least W 11 and W 12 is preferably a nitrogen atom, and W 11 , W 12 and W 13 It is more preferable that all of are nitrogen atoms.

[0121] That is, from the viewpoint of improving electron transport properties, the group bonded to the para position is W, in which two or three benzene rings are linked at the para position to extend the conjugation. 11 is preferably a nitrogen atom, and W 12 Plus W 12 or W 13 A pyrimidine structure in which one of W is a nitrogen atom is more preferred. 11 , W 12 and W 13 A triazine structure in which all atoms are nitrogen is most preferred.

[0122] <-(Xa 11 ) g11 -Xa 12 > In formula (1-1), Xa 11 At least one of the groups is preferably a 1,3-phenylene group. 11 ) g11 -Xa 12 is more preferably selected from the structure group of the following formula (Xa-1).

[0123] [ka]

[0124] In these structures, the hydrogen atoms may be substituted with a substituent selected from the below-described substituent group Q. Preferably, the hydrogen atoms are not substituted.

[0125] <-(Ya 11 ) h11 -Ya 12 > In formula (1-1), Ya 11 At least one of the groups is preferably a 1,3-phenylene group. 11 ) h11 -Ya 12 is more preferably selected from the structure group of the following formula (Ya-1).

[0126] [ka]

[0127] In these structures, Ya 12 All hydrogen atoms on the benzene ring, including the hydrogen atoms on the benzene ring of the N-carbazolyl group, may be substituted with a substituent selected from the below-described substituent group Q. Preferably, the structure has no substituted hydrogen atoms.

[0128] <-(Za 11 ) j11 -Za 12 > In formula (1-1), Za 11 At least one of the groups is preferably a 1,3-phenylene group. 11 ) j11 -Za 12 is more preferably selected from the structure group of the following formula (Za-1).

[0129] [ka]

[0130] In these structures, Za 12 All hydrogen atoms on the benzene ring, including the hydrogen atom on the benzene ring of the N-carbazolyl group, may be substituted with a substituent selected from the substituent group Q. Preferably, the structure has no hydrogen atoms substituted.

[0131] <f11> In formula (1-1), f11 is 1 or 2. From the viewpoint of solubility, f11 is preferably 1.

[0132] <R 11 > R in formula (1-1) 11 are each independently a hydrogen atom or a substituent. R is a substituent other than a hydrogen atom. 11 Examples of the substituent Q include groups selected from the substituent group Q described below. R when it is a substituent 11 is preferably an aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or an aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent. From the viewpoint of improving durability and charge transportability, an aromatic hydrocarbon group which may have a substituent is more preferred. When R is a substituent, 11 When there are a plurality of groups, they may be different from each other. R in formula (1-1) 11 is preferably a hydrogen atom.

[0133] <Preferred structure of the compound represented by formula (1-1)> In formula (1-1), h11 is preferably an integer of 2 or more, and is preferably 2 or 4. Furthermore, j11 is preferably an integer of 2 or more, and is preferably 2 or 4. When h11 and j11 are equal to or greater than the above lower limits, the solubility and stability are good.

[0134] In formula (1-1), Xa 11 At least one of Xa is preferably a 1,3-phenylene group. 11 It is more preferable that all of Xa are 1,3-phenylene groups. 11 The 1,3-phenylene group breaks the conjugation and increases the solubility. In addition, in formula (1-1), Ya 11 At least one of Ya is preferably a 1,3-phenylene group. 11 It is more preferable that all of Ya are 1,3-phenylene groups. 11 The 1,3-phenylene group breaks the conjugation and increases the solubility. In addition, in formula (1-1), Za 11 At least one of Za is preferably a 1,3-phenylene group. 11 It is more preferable that all of Za are 1,3-phenylene groups. 11 The 1,3-phenylene group breaks the conjugation and increases the solubility. In addition, in formula (1-1), Ya 11 At least one of Za is a 1,3-phenylene group, 11 At least one of these is preferably a 1,3-phenylene group.

[0135] <Molecular weight of the compound represented by formula (1-1)> The molecular weight of the compound represented by formula (1-1) is usually 5,000 or less, preferably 3,000 or less, more preferably 2,500 or less, particularly preferably 2,000 or less, and most preferably 1,800 or less. The lower limit of the molecular weight of the compound represented by formula (1-1) is preferably 350 or more, more preferably 400 or more, and particularly preferably 500 or more.

[0136] <Specific examples of compounds represented by formula (1-1)> The specific structure of the compound represented by formula (1-1) is not particularly limited, but examples include the following compounds.

[0137] [ka]

[0138] <Reason why the compound represented by formula (1-1) is effective> The compound represented by formula (1-1) is W 11 The group bonded to the para position of W is a group in which two or three benzene rings are linked at the para position, so conjugation is widespread, LUMO is distributed here, and it is thought that W has excellent electron transport properties. 11 Since the number of benzene rings conjugated to the para-position of the compound is three or less, the conjugation is not too long and the compound has a wide energy gap. Therefore, when the compound is used as a matrix material for an emitting layer, it is considered preferable because it is less likely to quench the emitting material.

[0139] W of the compound represented by formula (1-1) 11 , W 12 and W 13 In the nitrogen-containing six-membered ring containing the compound (1-1), the group bonded to the para position of W3 is a 1,3-phenylene group, and therefore is not conjugated. Therefore, the compound represented by formula (1-1) has a wide energy gap, and when used as a matrix material for an emitting layer, it is thought to be preferable because it is less likely to quench the emitting material. Ya of the compound represented by formula (1-1) 11 and Za 11 At least one of each of the groups is a 1,3-phenylene group, and therefore, Ya is an N-carbazolyl group. 12 or Za 12 Therefore, Compound A has a wide energy gap, and when used as a matrix material for the light-emitting layer, it is thought to be preferable because it is less likely to quench the light-emitting material.

[0140] Furthermore, -(Xa 11 ) g11 -Xa 12 , -(Ya 11 ) h11 -Ya 12 , -(Za 11 ) j11 -Za 12 When the compound has the above-mentioned preferred structure, it has a wide energy gap and is less likely to quench the light-emitting material when used as a matrix material for the light-emitting layer.

[0141] The compound represented by formula (1-1) is W 11 , W 12 and W 13 and the carbazolyl group, and contains an adequate number of 1,3-phenylene groups, and does not contain a 1,4-phenylene linkage structure longer than a terphenylene group, resulting in excellent solubility.

[0142] <Substituent group Q> The substituent group Q is a group consisting of alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, aryloxy groups, heteroaryloxy groups, alkoxycarbonyl groups, dialkylamino groups, diarylamino groups, arylalkylamino groups, acyl groups, halogen atoms, haloalkyl groups, alkylthio groups, arylthio groups, silyl groups, siloxy groups, cyano groups, aralkyl groups, aromatic hydrocarbon groups, and aromatic heterocyclic groups. These substituents may have any of a linear, branched, and cyclic structure.

[0143] More specifically, the substituent group Q includes the following structures. Examples of the alkyl group include linear, branched, or cyclic alkyl groups having a carbon number of usually 1 or more, preferably 4 or more, and usually 24 or less, preferably 12 or less, more preferably 8 or less, and even more preferably 6 or less, and preferable examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, a cyclohexyl group, and a dodecyl group. Examples of the alkenyl group include alkenyl groups having usually 2 or more carbon atoms and usually 24 or less, preferably 12 or less, such as a vinyl group. Examples of the alkynyl group include alkynyl groups having usually 2 or more carbon atoms and usually 24 or less, preferably 12 or less, such as ethynyl groups. The alkoxy group generally has 1 or more carbon atoms and generally 24 or less, preferably 12 or less, and examples thereof include alkoxy groups, and preferred examples include methoxy and ethoxy groups. The aryloxy group and heteroaryloxy group include an aryloxy group having usually 4 or more, preferably 5 or more, and usually 36 or less, preferably 24 or less carbon atoms, and preferable examples thereof include a phenoxy group, a naphthoxy group, and a pyridyloxy group. The alkoxycarbonyl group includes an alkoxycarbonyl group having usually 2 or more and usually 24 or less, preferably 12 or less carbon atoms, and preferably includes a methoxycarbonyl group and an ethoxycarbonyl group. The dialkylamino group includes a dialkylamino group having usually 2 or more and usually 24 or less, preferably 12 or less carbon atoms, and preferably includes a dimethylamino group and a diethylamino group. The diarylamino group generally has 10 or more carbon atoms, preferably 12 or more carbon atoms, and generally has 36 or less carbon atoms, preferably 24 or less carbon atoms. Preferred examples include a diphenylamino group and a ditolylamino group. The arylalkylamino group includes an arylalkylamino group having usually 7 or more and usually 36 or less, preferably 24 or less carbon atoms, and preferably includes a phenylmethylamino group. The acyl group generally has 2 or more carbon atoms, and generally 24 or less, preferably 12 or less, and preferred examples include an acetyl group and a benzoyl group. Examples of the halogen atom include a fluorine atom and a chlorine atom, with a fluorine atom being preferred. The haloalkyl group includes a haloalkyl group having usually 1 or more and usually 12 or less, preferably 6 or less carbon atoms, and preferably a trifluoromethyl group. The alkylthio group generally has 1 or more carbon atoms and generally 24 or less, preferably 12 or less, and is exemplified by alkylthio groups, preferably methylthio groups and ethylthio groups. The arylthio group includes an arylthio group having usually 4 or more, preferably 5 or more, and usually 36 or less, preferably 24 or less carbon atoms, and preferred examples include a phenylthio group, a naphthylthio group, and a pyridylthio group. The silyl group generally has 2 or more carbon atoms, preferably 3 or more carbon atoms, and generally has 36 or less carbon atoms, preferably 24 or less carbon atoms. Preferred examples include a trimethylsilyl group and a triphenylsilyl group. The siloxy group generally has 2 or more carbon atoms, preferably 3 or more carbon atoms, and generally has 36 or less carbon atoms, preferably 24 or less carbon atoms. Preferred examples include trimethylsiloxy groups and triphenylsiloxy groups. A cyano group is —CN. Examples of the aralkyl group include aralkyl groups having usually 7 or more, preferably 9 or more, and usually 30 or less, preferably 18 or less, and more preferably 10 or less, such as benzyl group, 2-phenylethyl group, 2-phenylpropyl-2-yl group, 2-phenylbutyl-2-yl group, 3-phenylpentyl-3-yl group, 3-phenyl-1-propyl group, 4-phenyl-1-butyl group, 5-phenyl-1-pentyl group, 6-phenyl-1-hexyl group, 7-phenyl-1-heptyl group, and 8-phenyl-1-octyl group. The aromatic hydrocarbon group generally has 6 or more carbon atoms and generally 36 or less carbon atoms, preferably 24 or less carbon atoms, and preferred examples include a phenyl group and a naphthyl group. The aromatic heterocyclic group includes an aromatic heterocyclic group having usually 3 or more, preferably 4 or more, and usually 36 or less, preferably 24 or less, carbon atoms, and preferred examples include a thienyl group and a pyridyl group.

[0144] Among the above-mentioned substituent group Q, alkyl groups, alkoxy groups, aromatic hydrocarbon groups, and aromatic heterocyclic groups are preferred. From the viewpoint of charge transportability, aromatic hydrocarbon groups or aromatic heterocyclic groups are preferred as the substituent, more preferably aromatic hydrocarbon groups, and even more preferably no substituent. From the viewpoint of improving solubility, alkyl groups or alkoxy groups are preferred as the substituent.

[0145] Each of the substituents in the above-mentioned substituent group Q may further have a substituent. Examples of such a substituent include the same as those in the above-mentioned substituents (substituent group Q). Each of the substituents that the substituents in the above-mentioned substituent group Q may further have is preferably an alkyl group having 8 or less carbon atoms, an alkoxy group having 8 or less carbon atoms, or a phenyl group, more preferably an alkyl group having 6 or less carbon atoms, an alkoxy group having 6 or less carbon atoms, or a phenyl group. From the viewpoint of charge transportability, it is more preferable that each of the substituents in the above-mentioned substituent group Q does not have any further substituent.

[0146] Compound A is a compound that satisfies the following formula (I): 4.20 <N A <5.80 Formula (I) In formula (I), N A represents the number of nitrogen atoms in compound A per 1000 molecular weight. For example, if compound A has a molecular weight of 1500 and has 7 nitrogen atoms, the N A This is calculated as 7 / (1500 / 1000) ≒ 4.67.

[0147] As shown in formula (I), N of compound A A If N is larger than 4.20, the electron transport property is good, and therefore the luminous efficiency of the organic electroluminescent device is high and the driving life is long. A is preferably 4.23 or more, and more preferably 4.26 or more.

[0148] On the other hand, N of compound A A If N is smaller than 5.80, the charge balance is good, and therefore the luminous efficiency of the organic electroluminescent device is high and the driving life is long. A is preferably 5.60 or less, more preferably 5.40 or less, even more preferably 5.20 or less, and particularly preferably 5.00 or less.

[0149] [Compound B] Compound B is preferably a compound represented by the following formula (240) or (241).

[0150] [ka]

[0151] (In formula (240), Ar 611 , Ar 612 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 611 , R 612 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. G represents a single bond or a divalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. n 611 , n 612 are each independently an integer of 0 to 4.

[0152] [ka]

[0153] (In formula (241), Ar 613 ~Ar 615 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 613 , R 614 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. Each G independently represents a single bond or a divalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. n 613 , n 614 are each independently an integer of 0 to 4.

[0154] (Ar 611 ~Ar 615 ) Ar 611 ~Ar 615 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. The aromatic hydrocarbon group typically has 6 to 50 carbon atoms, preferably 6 to 30 carbon atoms, and more preferably 6 to 18 carbon atoms. Specific examples of the aromatic hydrocarbon group include monovalent groups of aromatic hydrocarbon structures, such as benzene rings, naphthalene rings, anthracene rings, tetraphenylene rings, phenanthrene rings, chrysene rings, pyrene rings, benzanthracene rings, and perylene rings, each having a carbon number of typically 6 or more and typically 30 or less, preferably 18 or less, and more preferably 14 or less, or monovalent groups of structures in which multiple structures selected from these structures are linked in a chain or branched manner. When multiple aromatic hydrocarbon rings are linked, typically, a structure in which 2 to 8 rings are linked is used, and a structure in which 2 to 5 rings are linked is preferred. When multiple aromatic hydrocarbon rings are linked, the linked rings may be the same structure or different structures.

[0155] Ar 611 ~Ar 615 are preferably each independently phenyl group, a monovalent group in which multiple benzene rings are bonded in a chain or branched manner, a monovalent group in which one or more benzene rings and at least one naphthalene ring are bonded in a linear or branched manner, a monovalent group in which one or more benzene rings and at least one phenanthrene ring are bonded in a linear or branched manner, or a monovalent group in which one or more benzene rings and at least one tetraphenylene ring are bonded in a linear or branched manner; and more preferably a monovalent group in which a plurality of benzene rings are bonded in a linear or branched manner. In either case, the order of bonding does not matter. Ar 611 ~Ar 615 is particularly preferably each independently a monovalent group in which a plurality of benzene rings, which may have a substituent, are bonded in a chain or branched manner, and is most preferably each independently a monovalent group in which a plurality of benzene rings, which may have a substituent, are bonded in a chain or branched manner.

[0156] As described above, the number of linked benzene rings, naphthalene rings, phenanthrene rings, and tetraphenylene rings is usually 2 to 8, and preferably 2 to 5. Among these, preferred are monovalent groups in which 1 to 4 benzene rings are linked together, monovalent groups in which 1 to 4 benzene rings and a naphthalene ring are linked together, monovalent groups in which 1 to 4 benzene rings and a phenanthrene ring are linked together, and monovalent groups in which 1 to 4 benzene rings and a tetraphenylene ring are linked together.

[0157] These aromatic hydrocarbon groups may have a substituent. The substituent that the aromatic hydrocarbon group may have can be selected from the following substituent group Z2. Preferred substituents are the preferred substituents in the following substituent group Z2.

[0158] Ar 611 ~Ar 615 From the viewpoint of the solubility and durability of the compound, it is preferable that at least one of the above has at least one partial structure selected from the following formulae (72-1) to (72-7).

[0159] [ka]

[0160] In each of the above formulas (72-1) to (72-7), * represents a bonding position to an adjacent structure or a hydrogen atom, and at least one of the two * represents a bonding position to an adjacent structure. In the following description, * has the same definition unless otherwise specified.

[0161] More preferably, Ar 611 , Ar 612 At least one of the above has at least one partial structure selected from the formulae (72-1) to (72-4) and (72-7). More preferably, Ar 611 , Ar 612 Each of these has at least one partial structure selected from the formulae (72-1) to (72-3) and (72-7). Particularly preferably, Ar 611 , Ar 612 Each of these has at least one partial structure selected from the formula (72-1), the formula (72-2), and the formula (72-7).

[0162] Formula (72-2) is preferably the following formula (72-2-2).

[0163] [ka]

[0164] Formula (72-2) is more preferably the following formula (72-2-3).

[0165] [ka]

[0166] In addition, from the viewpoint of the solubility and durability of the compound, Ar 611 , Ar 612 The partial structure that at least one of the above preferably has includes a partial structure represented by formula (72-1) and a partial structure represented by formula (72-2).

[0167] (R 611 ~R 614 ) R 611 ~R 614 are each independently a deuterium atom, a halogen atom such as a fluorine atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. Preferably, R 611 ~R 614 are each independently a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms, more preferably 6 to 30 carbon atoms, still more preferably 6 to 18 carbon atoms, and particularly preferably 6 to 10 carbon atoms, which may have a substituent. Specific examples of the monovalent aromatic hydrocarbon group include the above-mentioned Ar 611 The same applies to the preferred aromatic hydrocarbon groups, with a phenyl group being particularly preferred. These aromatic hydrocarbon groups may have a substituent. The substituent that the aromatic hydrocarbon group may have is as described above, and specifically, can be selected from the following substituent group Z2. Preferred substituents are the preferred substituents in the following substituent group Z2.

[0168] (n 611 ~n 614 ) n 611 ~n 614 are each independently an integer of 0 to 4. 611 ~n 614 are each independently preferably an integer of 0 to 2, and more preferably 0 or 1.

[0169] (substituent) Ar 611 ~Ar 615 , R 611 ~R 614 When is a monovalent aromatic hydrocarbon group, the substituent that may be possessed is preferably a substituent selected from the following substituent group Z2.

[0170] <Substituent group Z2> The substituent group Z2 is a group consisting of an alkyl group, an alkoxy group, an aryloxy group, a heteroaryloxy group, an alkoxycarbonyl group, a dialkylamino group, a diarylamino group, an arylalkylamino group, an acyl group, a halogen atom, a haloalkyl group, an alkylthio group, an arylthio group, a silyl group, a siloxy group, a cyano group, an aromatic hydrocarbon group, and an aromatic heterocyclic group. These substituents may have any of a linear, branched, and cyclic structure.

[0171] More specifically, the substituent group Z2 includes the following structures. For example, a linear, branched, or cyclic alkyl group having a carbon number of usually 1 or more, preferably 4 or more, and usually 24 or less, preferably 12 or less, more preferably 8 or less, and even more preferably 6 or less, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, a cyclohexyl group, or a dodecyl group; For example, alkoxy groups having usually 1 or more and usually 24 or less, preferably 12 or less carbon atoms, such as a methoxy group or an ethoxy group; For example, an aryloxy group or heteroaryloxy group having usually 4 or more, preferably 5 or more, and usually 36 or less, preferably 24 or less, carbon atoms, such as a phenoxy group, naphthoxy group, or pyridyloxy group; For example, alkoxycarbonyl groups having usually 2 or more and usually 24 or less, preferably 12 or less carbon atoms, such as a methoxycarbonyl group or an ethoxycarbonyl group; For example, dialkylamino groups having usually 2 or more and usually 24 or less, preferably 12 or less carbon atoms, such as a dimethylamino group or a diethylamino group; For example, diarylamino groups such as diphenylamino groups and ditolylamino groups, each of which has usually 10 or more, preferably 12 or more, and usually 36 or less, preferably 24 or less carbon atoms; For example, an arylalkylamino group having typically 7 or more carbon atoms and typically 36 or less, preferably 24 or less, such as a phenylmethylamino group; For example, acyl groups such as an acetyl group and a benzoyl group, each of which usually has 2 or more carbon atoms and usually has 24 or less carbon atoms, and preferably has 12 or less carbon atoms; For example, halogen atoms such as fluorine atoms and chlorine atoms; For example, haloalkyl groups having typically 1 or more carbon atoms and typically 12 or less, preferably 6 or less, such as a trifluoromethyl group; For example, alkylthio groups having usually 1 or more and usually 24 or less, preferably 12 or less carbon atoms, such as a methylthio group or an ethylthio group; For example, an arylthio group having usually 4 or more, preferably 5 or more, and usually 36 or less, preferably 24 or less, carbon atoms, such as a phenylthio group, a naphthylthio group, or a pyridylthio group; For example, a silyl group having usually 2 or more, preferably 3 or more, carbon atoms and usually 36 or less, preferably 24 or less, such as a trimethylsilyl group or a triphenylsilyl group; For example, a siloxy group having a carbon number of usually 2 or more, preferably 3 or more, and usually 36 or less, preferably 24 or less, such as a trimethylsiloxy group or a triphenylsiloxy group; cyano group; For example, aromatic hydrocarbon groups such as phenyl and naphthyl groups, each having a carbon number of usually 6 or more and usually 36 or less, and preferably 24 or less; For example, aromatic heterocyclic groups having usually 3 or more, preferably 4 or more, carbon atoms and usually 36 or less, preferably 24 or less, such as a thienyl group or a pyridyl group.

[0172] Among the above-mentioned substituent group Z2, alkyl groups, alkoxy groups, diarylamino groups, aromatic hydrocarbon groups, and aromatic heterocyclic groups are preferred. From the viewpoint of charge transportability, aromatic hydrocarbon groups or aromatic heterocyclic groups are preferred as the substituent, more preferably aromatic hydrocarbon groups, and even more preferably no substituent. From the viewpoint of improving solubility, alkyl groups or alkoxy groups are preferred as the substituent.

[0173] Each substituent in the above-mentioned substituent group Z2 may further have a substituent. Examples of such a substituent include the same as those in the above-mentioned substituent group Z2. Each substituent that the above-mentioned substituent group Z2 may have is preferably an alkyl group having 8 or less carbon atoms, an alkoxy group having 8 or less carbon atoms, or a phenyl group, more preferably an alkyl group having 6 or less carbon atoms, an alkoxy group having 6 or less carbon atoms, or a phenyl group, and from the viewpoint of charge transportability, it is more preferable that each substituent in the above-mentioned substituent group Z2 does not have any further substituent.

[0174] (G) G represents a single bond or a divalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent.

[0175] The aromatic hydrocarbon group of G typically has 6 to 50 carbon atoms, preferably 6 to 30 carbon atoms, and more preferably 6 to 18 carbon atoms. Specific examples of the aromatic hydrocarbon group include divalent groups of aromatic hydrocarbon structures, such as benzene rings, naphthalene rings, anthracene rings, tetraphenylene rings, phenanthrene rings, chrysene rings, pyrene rings, benzanthracene rings, and perylene rings, each having a carbon number of typically 6 or more and typically 30 or less, preferably 18 or less, and more preferably 14 or less, or divalent groups of structures in which multiple structures selected from these structures are linked in a chain or branched manner. When multiple aromatic hydrocarbon rings are linked, typically, 2 to 8 rings are linked, and preferably 2 to 5 rings are linked. When multiple aromatic hydrocarbon rings are linked, the linked rings may be the same structure or different structures.

[0176] G is preferably single bond, a phenylene group, a divalent group in which multiple benzene rings are bonded in a chain or branched manner, a divalent group in which one or more benzene rings and at least one naphthalene ring are bonded in a linear or branched manner, a divalent group in which one or more benzene rings and at least one phenanthrene ring are bonded in a linear or branched manner, or a divalent group in which one or more benzene rings and at least one tetraphenylene ring are bonded in a linear or branched manner, and more preferably a divalent group in which a plurality of benzene rings are bonded in a linear or branched manner. In either case, the order of bonding is not important.

[0177] As described above, the number of linked benzene rings, naphthalene rings, phenanthrene rings, and tetraphenylene rings is usually 2 to 8, and preferably 2 to 5. Among these, more preferred are divalent groups in which 1 to 4 benzene rings are linked together, divalent groups in which 1 to 4 benzene rings and a naphthalene ring are linked together, divalent groups in which 1 to 4 benzene rings and a phenanthrene ring are linked together, and divalent groups in which 1 to 4 benzene rings and a tetraphenylene ring are linked together.

[0178] These aromatic hydrocarbon groups may have a substituent. The substituent that the aromatic hydrocarbon group may have can be selected from the aforementioned substituent group Z2. Preferred substituents are the preferred substituents in the aforementioned substituent group Z2.

[0179] Compound B is more preferably a compound represented by the following formula (240-1) or (241-1). [ka]

[0180] (In formula (240-1), Ar 611 , Ar 612 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 611 , R 612 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent.

[0181] [ka]

[0182] (In formula (241-1), Ar 613 ~Ar 615 each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R 613 , R 614 each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent.

[0183] (molecular weight) The compound represented by the formula (240), the formula (241), the formula (240-1), or the formula (241-1) is a low-molecular-weight material, and its molecular weight is preferably 3,000 or less, more preferably 2,500 or less, even more preferably 2,000 or less, particularly preferably 1,500 or less, and is usually 300 or more, preferably 350 or more, more preferably 400 or more.

[0184] (Specific examples of the compounds represented by the formula (240), the formula (241), the formula (240-1) or the formula (241-1)) Preferred specific examples of the compound represented by the formula (240), the formula (241), the formula (240-1) or the formula (241-1) are shown below, but the present invention is not limited to these.

[0185] [ka]

[0186] The composition according to the embodiment of the present invention may contain only one kind of compound represented by the formula (240), the formula (241), the formula (240-1), or the formula (241-1), or may contain two or more kinds of compounds.

[0187] Compound B is a compound that satisfies the following formula (II): 1.00 <N B <2.90 Formula (II) In formula (II), N B represents the number of nitrogen atoms in compound B per 1000 molecular weight.

[0188] As shown in formula (II), N of compound B B If N is greater than 1.00, the charge transport property is good, and therefore the luminous efficiency of the organic electroluminescent device is high and the driving life is long. B is preferably 1.50 or more, more preferably 2.00 or more, and even more preferably 2.50 or more.

[0189] On the other hand, N of compound B B If N is smaller than 2.90, the charge balance is good, and therefore the luminous efficiency of the organic electroluminescent device is high and the driving life is long. B is preferably 2.80 or less, more preferably 2.70 or less, and even more preferably 2.60 or less.

[0190] [Luminescent materials] The composition according to the embodiment of the present invention may contain a light-emitting material. The light-emitting material may be any known material that is generally used as a light-emitting material for organic electroluminescent devices, and is not particularly limited as long as it emits light at a desired emission wavelength and has good luminous efficiency. The light-emitting material may be a fluorescent compound or a phosphorescent compound, but is preferably a phosphorescent compound from the viewpoint of internal quantum efficiency. More preferably, the red and green light-emitting materials are phosphorescent compounds, and the blue light-emitting material is a fluorescent compound.

[0191] (Phosphorescent compounds) A phosphorescent compound is a compound that emits light from an excited triplet state. Representative examples include metal complex compounds containing Ir, Pt, Eu, etc., and the material structure preferably includes a metal complex. Among metal complexes, phosphorescent organometallic complexes that emit light via a triplet state include Werner complexes or organometallic complex compounds containing a central metal selected from Groups 7 to 11 of the long-form periodic table (hereinafter, unless otherwise specified, the term "periodic table" refers to the long-form periodic table). Examples of such phosphorescent compounds include the phosphorescent compounds described in International Publication Nos. WO 2014 / 024889, WO 2015 / 087961, WO 2016 / 194784, and JP 2014-074000 A. Compounds represented by the following formula (3) or formula (205) are preferred, and compounds represented by formula (3) are more preferred. That is, in the composition according to the embodiment of the present invention, the light-emitting material is preferably a compound represented by formula (3) or formula (205), and more preferably a compound represented by formula (3).

[0192] The composition according to the embodiment of the present invention may contain at least one compound represented by the following formula (3): In addition, the composition according to the embodiment of the present invention preferably further contains at least one compound represented by the above formula (240) and at least one compound represented by the above formula (260), in addition to the compound represented by the below formula (3).

[0193] [ka]

[0194] [In formula (3), Ring A1 represents an aromatic hydrocarbon structure which may have a substituent or an aromatic heterocyclic structure which may have a substituent. Ring A2 represents an aromatic heterocyclic structure which may have a substituent. R 201 , R 202 are each independently a structure represented by formula (b), and "*" represents the bonding position to ring A1 or ring A2. 201 , R 202 may be the same or different, and R 201 , R 202 When there are a plurality of each of the groups, they may be the same or different.

[0195] Ar 201 , Ar 203 each independently represents an aromatic hydrocarbon structure which may have a substituent, or an aromatic heterocyclic structure which may have a substituent. Ar 202 represents an aromatic hydrocarbon structure which may have a substituent, an aromatic heterocyclic structure which may have a substituent, or an aliphatic hydrocarbon structure which may have a substituent. The substituents bonded to ring A1 may bond to each other, the substituents bonded to ring A2 may bond to each other, or the substituents bonded to ring A1 and the substituents bonded to ring A2 may bond to each other to form a ring.

[0196] B 201 -L 200 -B 202 represents an anionic bidentate ligand. 201 and B 202 Each of L independently represents a carbon atom, an oxygen atom, or a nitrogen atom, and these atoms may be atoms constituting a ring. 200 is a single bond or B 201 and B 202 represents the atomic group that together with B constitutes a bidentate ligand. 201 -L 200 -B 202 When there are multiple groups, they may be the same or different.

[0197] In addition, in formula (3) and formula (b), i1 and i2 each independently represent an integer of 0 to 12, i3 is Ar 202 represents an integer greater than or equal to 0, with the upper limit being the number that can be replaced by i4 is Ar 201 represents an integer greater than or equal to 0, with the upper limit being the number that can be replaced by k1 and k2 each independently represent an integer of 0 or greater, the upper limit of which is the number of groups that can be substituted on ring A1 and ring A2; z represents an integer of 1 to 3. M represents a metal atom selected from Groups 7 to 11 of the periodic table.

[0198] In formula (3), specific examples of M include metal atoms selected from Groups 7 to 11 of the periodic table. Among these, preferred are ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold, and particularly preferred are trivalent metals such as iridium.

[0199] Unless otherwise specified, the substituent is preferably a group selected from the following substituent group S. Substituent group S: An alkyl group, preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 8 carbon atoms, and particularly preferably an alkyl group having 1 to 6 carbon atoms. An alkoxy group, preferably an alkoxy group having 1 to 20 carbon atoms, more preferably an alkoxy group having 1 to 12 carbon atoms, and even more preferably an alkoxy group having 1 to 6 carbon atoms. An aryloxy group, preferably an aryloxy group having 6 to 20 carbon atoms, more preferably an aryloxy group having 6 to 14 carbon atoms, even more preferably an aryloxy group having 6 to 12 carbon atoms, and particularly preferably an aryloxy group having 6 carbon atoms. A heteroaryloxy group, preferably a heteroaryloxy group having 3 to 20 carbon atoms, more preferably a heteroaryloxy group having 3 to 12 carbon atoms. An alkylamino group, preferably an alkylamino group having 1 to 20 carbon atoms, more preferably an alkylamino group having 1 to 12 carbon atoms.

[0200] An arylamino group, preferably an arylamino group having 6 to 36 carbon atoms, more preferably an arylamino group having 6 to 24 carbon atoms. An aralkyl group, preferably an aralkyl group having 7 to 40 carbon atoms, more preferably an aralkyl group having 7 to 18 carbon atoms, and even more preferably an aralkyl group having 7 to 12 carbon atoms. Heteroaralkyl groups, preferably heteroaralkyl groups having 7 to 40 carbon atoms, more preferably heteroaralkyl groups having 7 to 18 carbon atoms. An alkenyl group, preferably an alkenyl group having 2 to 20 carbon atoms, more preferably an alkenyl group having 2 to 12 carbon atoms, even more preferably an alkenyl group having 2 to 8 carbon atoms, and particularly preferably an alkenyl group having 2 to 6 carbon atoms. An alkynyl group, preferably an alkynyl group having 2 to 20 carbon atoms, more preferably an alkynyl group having 2 to 12 carbon atoms.

[0201] An aryl group, preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 24 carbon atoms, even more preferably an aryl group having 6 to 18 carbon atoms, and particularly preferably an aryl group having 6 to 14 carbon atoms. Heteroaryl groups, preferably heteroaryl groups having 3 to 30 carbon atoms, more preferably heteroaryl groups having 3 to 24 carbon atoms, even more preferably heteroaryl groups having 3 to 18 carbon atoms, and particularly preferably heteroaryl groups having 3 to 14 carbon atoms. An alkylsilyl group, preferably an alkylsilyl group having an alkyl group with 1 to 20 carbon atoms, more preferably an alkylsilyl group having an alkyl group with 1 to 12 carbon atoms. An arylsilyl group, preferably an arylsilyl group having 6 to 20 carbon atoms in the aryl group, more preferably an arylsilyl group having 6 to 14 carbon atoms in the aryl group. An alkylcarbonyl group, preferably an alkylcarbonyl group having 2 to 20 carbon atoms. An arylcarbonyl group, preferably an arylcarbonyl group having 7 to 20 carbon atoms. In the above groups, one or more hydrogen atoms may be replaced by fluorine atoms, or one or more hydrogen atoms may be replaced by deuterium atoms. Unless otherwise specified, aryl is an aromatic hydrocarbon ring and heteroaryl is an aromatic heterocyclic ring.

[0202] -Hydrogen atom, deuterium atom, fluorine atom, cyano group, or -SF5.

[0203] Among the substituent group S, preferred are an alkyl group, an alkoxy group, an aryloxy group, an arylamino group, an aralkyl group, an alkenyl group, an aryl group, a heteroaryl group, an alkylsilyl group, an arylsilyl group, and groups in which one or more hydrogen atoms of these groups are replaced by fluorine atoms, a fluorine atom, a cyano group, or -SF5; More preferably, it is an alkyl group, an arylamino group, an aralkyl group, an alkenyl group, an aryl group, a heteroaryl group, a group in which one or more hydrogen atoms of these groups are replaced with fluorine atoms, a fluorine atom, a cyano group, or -SF5; More preferred are alkyl groups, alkoxy groups, aryloxy groups, arylamino groups, aralkyl groups, alkenyl groups, aryl groups, heteroaryl groups, alkylsilyl groups, and arylsilyl groups. Particularly preferred are alkyl groups, arylamino groups, aralkyl groups, alkenyl groups, aryl groups, and heteroaryl groups. Most preferred are alkyl groups, arylamino groups, aralkyl groups, aryl groups and heteroaryl groups.

[0204] These substituents in the substituent group S may further have a substituent selected from the substituent group S as a substituent. The preferred groups, more preferred groups, even more preferred groups, particularly preferred groups, and most preferred groups of the substituents that may be had are the same as the preferred groups in the substituent group S.

[0205] Ring A1 represents an aromatic hydrocarbon structure which may have a substituent or an aromatic heterocyclic structure which may have a substituent. The aromatic hydrocarbon ring is preferably an aromatic hydrocarbon ring having a carbon number of 6 to 30. Specifically, a benzene ring, a naphthalene ring, an anthracene ring, a triphenylyl ring, an acenaphthene ring, a fluoranthene ring, or a fluorene ring is preferred. The aromatic heterocycle is preferably an aromatic heterocycle having 3 to 30 carbon atoms and containing a nitrogen atom, oxygen atom, or sulfur atom as a heteroatom, more preferably a furan ring, a benzofuran ring, a thiophene ring, or a benzothiophene ring.

[0206] Ring A1 is more preferably a benzene ring, a naphthalene ring, or a fluorene ring, particularly preferably a benzene ring or a fluorene ring, and most preferably a benzene ring.

[0207] Ring A2 represents an aromatic heterocyclic structure which may have a substituent. The aromatic heterocycle is preferably an aromatic heterocycle having 3 to 30 carbon atoms and containing a nitrogen atom, oxygen atom, or sulfur atom as a heteroatom. Specific examples include a pyridine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, an imidazole ring, an oxazole ring, a thiazole ring, a benzothiazole ring, a benzoxazole ring, a benzimidazole ring, a quinoline ring, an isoquinoline ring, a quinoxaline ring, a quinazoline ring, a naphthyridine ring, and a phenanthridine ring. Preferred are a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, a benzothiazole ring, a benzoxazole ring, a quinoline ring, an isoquinoline ring, a quinoxaline ring, and a quinazoline ring. More preferred are a pyridine ring, an imidazole ring, a benzothiazole ring, a quinoline ring, an isoquinoline ring, a quinoxaline ring, and a quinazoline ring. Most preferred are a pyridine ring, an imidazole ring, a benzothiazole ring, a quinoline ring, a quinoxaline ring, and a quinazoline ring.

[0208] Preferred combinations of ring A1 and ring A2, when expressed as (ring A1-ring A2), include (benzene ring-pyridine ring), (benzene ring-quinoline ring), (benzene ring-quinoxaline ring), (benzene ring-quinazoline ring), (benzene ring-benzothiazole ring), (benzene ring-imidazole ring), (benzene ring-pyrrole ring), (benzene ring-diazole ring), and (benzene ring-thiophene ring). The substituents that the ring A1 and ring A2 may have can be selected arbitrarily, but are preferably one or more types of substituents selected from the above-mentioned group S of substituents.

[0209] Ar 201 , Ar 203 each independently represents an aromatic hydrocarbon structure which may have a substituent, or an aromatic heterocyclic structure which may have a substituent. Ar 202 represents an aromatic hydrocarbon structure which may have a substituent, an aromatic heterocyclic structure which may have a substituent, or an aliphatic hydrocarbon structure which may have a substituent.

[0210] Ar 201 , Ar 202 , Ar 203 When any one of the above is an aromatic hydrocarbon structure which may have a substituent, the aromatic hydrocarbon structure is preferably an aromatic hydrocarbon ring having a carbon number of 6 to 30. Specifically, a benzene ring, a naphthalene ring, an anthracene ring, a triphenylyl ring, an acenaphthene ring, a fluoranthene ring, or a fluorene ring is preferred, a benzene ring, a naphthalene ring, or a fluorene ring is more preferred, and a benzene ring is most preferred.

[0211] Ar 201 , Ar 202 When any of the above is a benzene ring which may have a substituent, it is preferable that at least one benzene ring is bonded to an adjacent structure at an ortho-position or a meta-position, and it is more preferable that at least one benzene ring is bonded to an adjacent structure at a meta-position.

[0212] Ar 201 , Ar 202 , Ar 203 When either of the above is a fluorene ring which may have a substituent, the 9- and 9'-positions of the fluorene ring preferably have a substituent or are bonded to an adjacent structure.

[0213] Ar 201 , Ar 202 , Ar 203 is an aromatic heterocyclic structure which may have a substituent, the aromatic heterocyclic structure is preferably an aromatic heterocyclic ring having 3 to 30 carbon atoms and containing a nitrogen atom, an oxygen atom, or a sulfur atom as a heteroatom, and specific examples thereof include a pyridine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, an imidazole ring, an oxazole ring, a thiazole ring, a benzothiazole ring, a benzoxazole ring, a benzimidazole ring, a quinoline ring, an isoquinoline ring, a quinoxaline ring, a quinazoline ring, a naphthyridine ring, a phenanthridine ring, a carbazole ring, a dibenzofuran ring, and a dibenzothiophene ring, and preferably a pyridine ring, a pyrimidine ring, a triazine ring, a carbazole ring, a dibenzofuran ring, or a dibenzothiophene ring. Ar 201 , Ar 202 , Ar 203 When either of the above is a carbazole ring which may have a substituent, the N-position of the carbazole ring preferably has a substituent or is bonded to an adjacent structure.

[0214] Ar 202 When is an aliphatic hydrocarbon structure which may have a substituent, it is an aliphatic hydrocarbon structure having a linear, branched, or cyclic structure, and preferably has 1 or more and 24 or less carbon atoms, more preferably has 1 or more and 12 or less carbon atoms, and even more preferably has 1 or more and 8 or less carbon atoms.

[0215] i1 and i2 each independently represent an integer of 0 to 12, preferably an integer of 1 to 12, more preferably an integer of 1 to 8, and even more preferably an integer of 1 to 6. Within this range, improvements in solubility and charge transport properties are expected. i3 preferably represents an integer of 0 to 5, more preferably an integer of 0 to 2, and even more preferably 0 or 1. i4 preferably represents an integer of 0 to 2, and more preferably 0 or 1. k1 and k2 each independently represent an integer of preferably 0 to 3, more preferably an integer of 1 to 3, even more preferably 1 or 2, and particularly preferably 1.

[0216] Ar 201 , Ar 202 , Ar 203 The substituents that may be possessed by may be arbitrarily selected, but are preferably one or more substituents selected from the above-mentioned substituent group S. The preferred groups are also the same as those in the above-mentioned substituent group S, but are more preferably unsubstituted (hydrogen atom), alkyl groups, or aryl groups, particularly preferably unsubstituted (hydrogen atom) or alkyl groups, and most preferably unsubstituted (hydrogen atom) or tertiary butyl groups, and the tertiary butyl groups are preferably Ar 203 If Ar exists, 203 To, Ar 203 If Ar does not exist, 202 To, Ar 202 and Ar 203 If Ar does not exist, 201 It is preferred that the substituent is

[0217] The compound represented by the formula (3) is preferably a compound that satisfies one or more of the following (I) to (IV):

[0218] (I) Phenylene-linked The structure represented by formula (b) is preferably a structure having a group linked to benzene rings, i.e., a benzene ring structure, where i1 is an integer of 1 to 6, and at least one of the benzene rings is bonded to an adjacent structure at the ortho or meta position. Such a structure is expected to improve solubility and charge transport properties.

[0219] (II) (phenylene)-aralkyl(alkyl) A structure having an aromatic hydrocarbon group or aromatic heterocyclic group to which an alkyl group or an aralkyl group is bonded in ring A1 or ring A2, i.e., Ar 201 is an aromatic hydrocarbon structure or an aromatic heterocyclic structure, i1 is an integer of 1 to 6, Ar 202 is an aliphatic hydrocarbon structure, i2 is an integer of 1 to 12, preferably an integer of 3 to 8, Ar 203 is a benzene ring structure, i3 is 0 or 1, preferably Ar 201 is the aromatic hydrocarbon structure, more preferably a structure in which 1 to 5 benzene rings are linked together, and even more preferably a structure in which there is one benzene ring. Such a structure is expected to improve solubility and charge transport properties.

[0220] (III) Dendron A structure in which a dendron is bonded to ring A1 or ring A2, for example, Ar 201 , Ar 202 is a benzene ring structure, Ar 203 is a biphenyl or terphenyl structure, i1 and i2 are integers of 1 to 6, i3 is 2, and j is 2. Such a structure is expected to improve solubility and charge transport properties.

[0221] (IV)B 201 -L 200 -B 202 B 201 -L 200 -B 202 The structure represented by the formula (203) is preferably a structure represented by the formula (204) below.

[0222] [ka]

[0223] In formula (203), R 211 , R 212 , R 213 each independently represents a substituent. In formula (204), ring B3 represents an aromatic heterocyclic structure containing a nitrogen atom, which may have a substituent, and ring B3 is preferably a pyridine ring.

[0224] The phosphorescent compound represented by the formula (201) is not particularly limited, but preferred examples include the following.

[0225] [ka]

[0226] [ka]

[0227] [ka]

[0228] Also preferred is a phosphorescent compound represented by the following formula (205):

[0229] [ka]

[0230] [In formula (205), M 2 represents a metal, and T represents a carbon atom or a nitrogen atom. 92 ~R 95 each independently represents a substituent, provided that when T is a nitrogen atom, R 94 and R 95 There is none.]

[0231] In formula (205), M 2 Specific examples of the metal include metals selected from Groups 7 to 11 of the periodic table. Among these, preferred are ruthenium, rhodium, palladium, silver, rhenium, osmium, iridium, platinum, and gold, and particularly preferred are divalent metals such as platinum and palladium.

[0232] Also, in equation (205), R 92 and R 93 each independently represents a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an alkenyl group, a cyano group, an amino group, an acyl group, an alkoxycarbonyl group, a carboxy group, an alkoxy group, an alkylamino group, an aralkylamino group, a haloalkyl group, a hydroxyl group, an aryloxy group, an aromatic hydrocarbon group, or an aromatic heterocyclic group.

[0233] Furthermore, if T is a carbon atom, R 94 and R 95 are each independently R 92 and R 93 In addition, when T is a nitrogen atom, R 94 or R 95 does not exist. Also, R 92 ~R 95 may further have a substituent. The substituent may be the same as those described above. 92 ~R 95 Any two or more of the groups may be linked to each other to form a ring.

[0234] The molecular weight of the phosphorescent compound is preferably 5,000 or less, more preferably 4,000 or less, and particularly preferably 3,000 or less. The molecular weight of the phosphorescent compound is preferably 1,200 or more, more preferably 1,400 or more, and even more preferably 1,600 or more. It is believed that within this molecular weight range, the phosphorescent compounds do not aggregate with each other and can be uniformly mixed with the charge transport material, thereby making it possible to obtain a light-emitting layer with high luminous efficiency.

[0235] The molecular weight of the phosphorescent compound is preferably large in that it has a high Tg, melting point, decomposition temperature, etc., and the heat resistance of the phosphorescent compound and the formed light-emitting layer is excellent, and it is less likely to cause deterioration in film quality due to gas generation, recrystallization, molecular migration, etc., or an increase in impurity concentration due to thermal decomposition of the material. On the other hand, the molecular weight of the phosphorescent compound is preferably small in that it makes it easier to purify the organic compound.

[0236] [Compound (260)] <Compound represented by formula (260)> The composition according to the embodiment of the present invention may further contain at least one compound represented by the following formula (260):

[0237] The compound (260) is a compound represented by the following formula (260).

[0238] <Compound represented by formula (260)>

[0239] [ka]

[0240] (In formula (260), Ar 21 ~Ar 35 each independently represents a hydrogen atom, a phenyl group which may have a substituent, or a monovalent group in which 2 to 10 phenyl groups which may have a substituent are linked in an unbranched or branched manner.

[0241] In formula (260), Ar 21 ~Ar 35 is a phenyl group which may have a substituent, or in the case where 2 to 10 phenyl groups which may have a substituent are linked in an unbranched or branched manner, the substituent which the phenyl group may have is preferably an alkyl group.

[0242] (Alkyl group as a substituent) The alkyl group as a substituent is a linear, branched, or cyclic alkyl group having a carbon number of usually 1 or more and 12 or less, preferably 8 or less, more preferably 6 or less, and even more preferably 4 or less. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-hexyl group, a cyclohexyl group, and a 2-ethylhexyl group.

[0243] In the formula (260), Ar 21 , Ar 25 , Ar 26 , Ar 30 , Ar 31 and Ar 35 is preferably a hydrogen atom. 22 ~Ar 24 At least one of the groups is a phenyl group which may have a substituent or a monovalent group in which 2 to 10 phenyl groups which may have a substituent are linked in an unbranched or branched manner, and / or Ar 22 ~Ar 24 At least one of, and Ar 27 ~Ar 29 At least one of the groups is preferably a phenyl group which may have the above-mentioned substituent or a monovalent group in which 2 to 10 phenyl groups which may have the above-mentioned substituent are linked in an unbranched or branched manner. 22 ~Ar 24 , Ar 27 ~Ar 29 , and Ar 32 ~Ar 34 is a hydrogen atom, a phenyl group, or a structure selected from the following formulas (261-1) to (261-9). Particularly preferably, in the formula (260), Ar 21 , Ar 25 , Ar 26 , Ar 30 , Ar 31 and Ar 35 is a hydrogen atom, and Ar 22 ~Ar 24 , Ar 27 ~Ar 29 , and Ar 32 ~Ar 34 are each independently a hydrogen atom, a phenyl group which may have a substituent, or a structure selected from the following formulas (261-1) to (261-9), each of which may have a substituent. These structures may have the substituent, for example, may be substituted with an alkyl group as the substituent. From the viewpoint of improving solubility, it is preferable that they be substituted with an alkyl group. From the viewpoint of charge transport properties and durability during device operation, it is preferable that they have no substituent.

[0244] [ka]

[0245] In the formulae (261-1) to (261-9), * represents the bonding position to the benzene ring in the formula (260).

[0246] It is believed that the inclusion of such a structure in the compound represented by formula (260) allows the charge transport property in the light-emitting layer to be appropriately adjusted, thereby increasing the light-emitting efficiency. It is also believed that the inclusion of such a structure provides excellent solubility and durability during device operation.

[0247] (molecular weight) The compound represented by the formula (260) is a low molecular weight material, and its molecular weight is preferably 3,000 or less, more preferably 2,500 or less, even more preferably 2,000 or less, particularly preferably 1,500 or less, and is usually 300 or more, preferably 350 or more, more preferably 400 or more.

[0248] (Specific examples of compounds represented by formula (260)) The compound represented by formula (260) is not particularly limited, but examples thereof include the following compounds.

[0249] [ka]

[0250] [ka]

[0251] The composition according to the embodiment of the present invention may contain only one type of compound represented by the formula (260), or may contain two or more types.

[0252] [Organic solvents] The composition according to an embodiment of the present invention may contain an organic solvent, and the organic solvent is a volatile liquid component used to form a layer containing the compound according to an embodiment of the present invention by wet film formation. The organic solvent is not particularly limited as long as it is an organic solvent in which the compound according to the embodiment of the present invention, which is the solute, and the light-emitting material described below can be well dissolved.

[0253] Preferred organic solvents include, for example, alkanes such as n-decane, cyclohexane, ethylcyclohexane, decalin, and bicyclohexane; aromatic hydrocarbons such as toluene, xylene, mesitylene, phenylcyclohexane (cyclohexylbenzene), tetralin, and methylnaphthalene; halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene, and trichlorobenzene; 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole, and diphenyl ether. aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate; alicyclic ketones such as cyclohexanone, cyclooctanone, and fenchone; alicyclic alcohols such as cyclohexanol and cyclooctanol; aliphatic ketones such as methyl ethyl ketone and dibutyl ketone; aliphatic alcohols such as butanol and hexanol; and aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, and propylene glycol-1-monomethyl ether acetate (PGMEA).

[0254] Among these, from the viewpoints of viscosity and boiling point, alkanes, aromatic hydrocarbons, aromatic ethers, and aromatic esters are preferred, aromatic hydrocarbons, aromatic ethers, and aromatic esters are more preferred, and aromatic hydrocarbons and aromatic esters are particularly preferred. These organic solvents may be used singly or in any combination of two or more in any ratio.

[0255] The boiling point of the organic solvent used is usually 80°C or higher, preferably 100°C or higher, more preferably 120°C or higher, and usually 380°C or lower, preferably 350°C or lower, more preferably 330°C or lower. If the boiling point of the organic solvent is below this range, the film formation stability may decrease during wet film formation due to solvent evaporation from the composition. If the boiling point of the organic solvent is above this range, the film formation stability may decrease during wet film formation due to solvent residue after film formation.

[0256] In particular, a uniform coating film can be produced by combining two or more of the above organic solvents having a boiling point of 150° C. or higher. If there is only one or more organic solvents having a boiling point of 150° C. or higher, it is thought that a uniform film may not be formed during coating.

[0257] [Organic electroluminescent device] The organic electroluminescent device according to this embodiment has a light-emitting layer formed using the composition according to this embodiment. The light-emitting layer is preferably formed by a wet film-forming method.

[0258] The organic electroluminescent device preferably has at least an anode, a cathode, and at least one organic layer between the anode and the cathode on a substrate, and at least one of the organic layers is formed using the composition according to this embodiment. It is more preferable that such a layer is formed by a wet film-forming method. Furthermore, the organic layer includes a light-emitting layer, and it is more preferable that this light-emitting layer is formed using the composition according to this embodiment.

[0259] In this specification, the term "wet film formation method" refers to a film formation method, i.e., a coating method, which employs a wet film formation method such as spin coating, dip coating, die coating, bar coating, blade coating, roll coating, spray coating, capillary coating, inkjet printing, nozzle printing, screen printing, gravure printing, or flexographic printing, and then dries the film formed by such a method to form a film.

[0260] FIG. 1 is a schematic cross-sectional view showing a preferred structural example of an organic electroluminescent device 8 according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a substrate, reference numeral 2 denotes an anode, reference numeral 3 denotes a hole injection layer, reference numeral 4 denotes a hole transport layer, reference numeral 5 denotes a light emitting layer, reference numeral 6 denotes an electron transport layer, and reference numeral 7 denotes a cathode.

[0261] The materials used in these structures can be known materials and are not particularly limited, but representative materials and manufacturing methods for each layer are described below as examples. When publications, papers, etc. are cited below, the relevant content can be applied and adapted as appropriate within the scope of common sense of a person skilled in the art.

[0262] <Board 1> The substrate 1 serves as a support for the organic electroluminescent element. Examples of substrate 1 that can be used include quartz or glass plates, metal plates or foils, and plastic films or sheets. Glass plates and transparent synthetic resin plates such as polyester, polymethacrylate, polycarbonate, and polysulfone are particularly preferred. When using a synthetic resin substrate, it is preferable to pay attention to its gas barrier properties. It is preferable for the gas barrier properties of the substrate to be high, since this makes it difficult for the organic electroluminescent element to be deteriorated by the outside air passing through the substrate. Therefore, one preferred method is to ensure gas barrier properties by providing a dense silicon oxide film or the like on at least one side of the synthetic resin substrate.

[0263] <Anode 2> The anode 2 is an electrode that serves to inject holes into the layer on the light-emitting layer 5 side. The anode 2 is usually made of a metal such as aluminum, gold, silver, nickel, palladium, or platinum; a metal oxide such as indium and / or tin oxide; a metal halide such as copper iodide; carbon black; or a conductive polymer such as poly(3-methylthiophene), polypyrrole, or polyaniline.

[0264] The anode 2 is usually formed by a method such as sputtering or vacuum deposition. When forming the anode 2 using metal fine particles such as silver, fine particles such as copper iodide, carbon black, conductive metal oxide fine particles, conductive polymer fine powder, or the like, the anode 2 can also be formed by dispersing these fine particles in an appropriate binder resin solution and applying the solution to the substrate 1. In the case of a conductive polymer, a thin film can be formed directly on the substrate 1 by electrolytic polymerization. The anode 2 can also be formed by applying a conductive polymer onto the substrate 1 (Appl. Phys. Lett., Vol. 60, p. 2711, 1992).

[0265] The anode 2 usually has a single layer structure, but can also have a laminated structure made of multiple materials if desired.

[0266] The thickness of the anode 2 may be appropriately selected depending on the required transparency, etc. When transparency is required, it is preferable that the visible light transmittance is usually 60% or more, preferably 80% or more. In this case, the thickness of the anode 2 is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less. When opaqueness is sufficient, the thickness of the anode 2 is optional. A substrate 1 that also functions as the anode 2 may be used. It is also possible to laminate a different conductive material on the above-mentioned anode 2.

[0267] It is preferable to subject the surface of the anode 2 to ultraviolet (UV) / ozone treatment, oxygen plasma treatment, or argon plasma treatment in order to remove impurities adhering to the anode 2 and adjust the ionization potential to improve hole injection properties.

[0268] <Hole injection layer 3> The hole injection layer 3 is a layer that transports holes from the anode 2 to the light emitting layer 5. When the hole injection layer 3 is provided, the hole injection layer 3 is usually formed on the anode 2. The method for forming the hole injection layer 3 is not particularly limited and may be a vacuum deposition method or a wet film formation method. From the viewpoint of reducing dark spots, the hole injection layer 3 is preferably formed by a wet film formation method. When the hole injection layer is formed by a wet film formation method, it is formed using a composition for forming a hole injection layer. When forming the hole injection layer by a wet film formation method, it is preferable to heat the composition after coating and drying. The heating temperature is preferably 120°C or higher, more preferably 150°C or higher, and even more preferably 180°C or higher, and is preferably 300°C or lower, and more preferably 260°C or lower. The thickness of the hole injection layer 3 is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less.

[0269] (hole transport material) The composition for forming a hole injection layer usually contains a hole transport material and an organic solvent as constituent materials of the hole injection layer 3. Examples of the organic solvent contained in the composition for forming a hole injection layer include the same organic solvents as those exemplified as the organic solvents contained in the composition according to the embodiment of the present invention. The hole transport material is generally used in the hole injection layer 3 of an organic electroluminescent element, and may be a high molecular weight compound such as a polymer or a low molecular weight compound such as a monomer, as long as it has hole transport properties. However, a high molecular weight compound is preferred.

[0270] The hole transport material is preferably a compound having an ionization potential of 4.5 eV to 6.0 eV from the viewpoint of the charge injection barrier from the anode 2 to the hole injection layer 3. Examples of the hole transport material include aromatic amine derivatives, phthalocyanine derivatives, porphyrin derivatives, oligothiophene derivatives, polythiophene derivatives, benzylphenyl derivatives, compounds in which a tertiary amine is linked via a fluorene group, hydrazone derivatives, silazane derivatives, silanamine derivatives, phosphamine derivatives, quinacridone derivatives, polyaniline derivatives, polypyrrole derivatives, polyphenylene vinylene derivatives, polythienylene vinylene derivatives, polyquinoline derivatives, polyquinoxaline derivatives, and carbon.

[0271] In the present invention, the derivative, for example, in the case of an aromatic amine derivative, includes the aromatic amine itself and a compound having an aromatic amine as the main skeleton, and may be either a polymer or a monomer. The hole transport material used as the material for the hole injection layer 3 may contain any one of these compounds alone or may contain two or more of them. When two or more hole transport materials are contained, they may be combined in any desired manner, but it is preferable to use one or more aromatic tertiary amine polymer compounds in combination with one or more other hole transport materials.

[0272] Among the above-listed hole transport materials, aromatic amine compounds are preferred, and aromatic tertiary amine compounds are particularly preferred, from the viewpoints of amorphousness and visible light transmittance. The aromatic tertiary amine compounds are compounds having an aromatic tertiary amine structure and also include compounds having a group derived from an aromatic tertiary amine.

[0273] The type of aromatic tertiary amine compound is not particularly limited, but from the viewpoint of uniform light emission due to the surface smoothing effect, a polymer compound (polymerized compound having a series of repeating units) having a weight average molecular weight of 1,000 or more and 1,000,000 or less is more preferred. Preferred examples of aromatic tertiary amine polymer compounds include polymer compounds having repeating units represented by the following formula (51) or (61):

[0274] [ka]

[0275] (In formula (51), Ar 3 represents an aromatic hydrocarbon group or an aromatic heterocyclic group, each of which may have a substituent; Ar 4 represents a divalent aromatic hydrocarbon group or a divalent aromatic heterocyclic group, each of which may have a substituent, or a divalent group in which a plurality of such aromatic hydrocarbon groups and aromatic heterocyclic groups are linked together directly or via a linking group.

[0276] In the formula (51), when a plurality of aromatic hydrocarbon groups and aromatic heterocyclic groups are linked via a linking group, the linking group is a divalent linking group, and examples thereof include a group formed by linking 1 to 30, preferably 1 to 5, and more preferably 1 to 3 groups selected from an -O- group, a -C(=O)- group, and a (optionally substituted) -CH2- group in any order.

[0277] Among the linking groups, Ar in formula (51) is preferred because it is excellent in injecting holes into the light-emitting layer. 4 is preferably an aromatic hydrocarbon group or aromatic heterocyclic group, a plurality of which are linked via a linking group represented by the following formula (52).

[0278] [ka]

[0279] (In formula (52), d represents an integer of 1 to 10, and R 8 and R 9 each independently represents a hydrogen atom or an alkyl group, an aromatic hydrocarbon group, or an aromatic heterocyclic group, each of which may have a substituent. R 8 , R 9 If there are multiple, they may be the same or different.)

[0280] [ka]

[0281] In the above formula (61), j, k, l, m, n, and p each independently represent an integer of 0 or more, provided that l+m≧1. 11 , Ar 12 , Ar 14 each independently represents a divalent aromatic ring group having 30 or less carbon atoms which may have a substituent. 13 represents a divalent aromatic ring group having 30 or less carbon atoms which may have a substituent or a divalent group represented by the following formula (62), and Q 11 , Q 12 each independently represents an oxygen atom, a sulfur atom, or a hydrocarbon chain having 6 or less carbon atoms which may have a substituent; S 1 ~S 4 are each independently represented by a group represented by the following formula (63): The aromatic ring group referred to here refers to an aromatic hydrocarbon group and an aromatic heterocyclic group.

[0282] Ar 11 , Ar 12 , Ar 14 Examples of the aromatic ring group include a monocyclic ring, a group having 2 to 6 condensed rings, or a group in which two or more of these aromatic rings are linked together. Specific examples of the aromatic ring group having a monocyclic ring or a group having 2 to 6 condensed rings include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, an acenaphthene ring, a fluoranthene ring, a fluorene ring, a biphenyl group, a terphenyl group, a quaterphenyl group, a furan ring, a benzofuran ring, a thiophene ring, a benzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, a carbazole ring, a pyrrolyl imidazoline ring, a pyrrolidinyl ... Examples of suitable divalent groups include a divalent group derived from a benzene ring, a pyrrolopyrazole ring, a pyrrolopyrrole ring, a thienopyrrole ring, a thienothiophene ring, a furopyrrole ring, a furofuran ring, a thienofuran ring, a benzisoxazole ring, a benzisothiazole ring, a benzimidazole ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinoxaline ring, a phenanthridine ring, a benzimidazole ring, a perimidine ring, a quinazoline ring, a quinazolinone ring, or an azulene ring. Among these, a divalent group derived from a benzene ring, a naphthalene ring, a fluorene ring, a pyridine ring, or a carbazole ring, or a biphenyl group, is preferred because they efficiently delocalize negative charges and are excellent in stability and heat resistance.

[0283] Ar 13 Examples of aromatic ring groups include Ar 11 , Ar 12 , Ar 14 This is the same as in the case of

[0284] [ka]

[0285] In the above formula (62), R 11 R represents an alkyl group, an aromatic ring group, or a trivalent group consisting of an alkyl group having 40 or less carbon atoms and an aromatic ring group, which may have a substituent. 12 represents an alkyl group, an aromatic ring group, or a divalent group consisting of an alkyl group having 40 or less carbon atoms and an aromatic ring group, which may have a substituent. 31 represents a monovalent aromatic ring group or a monovalent crosslinking group, and these groups may have a substituent. q represents an integer of 1 to 4. When q is 2 or more, multiple R 12 may be the same or different, and multiple Ar 31 may be the same or different. The asterisk (*) indicates the bonding position to the nitrogen atom in formula (61).

[0286] R 11 The aromatic ring group is preferably one aromatic ring group which is a monocyclic or fused ring having from 3 to 30 carbon atoms, or a group in which 2 to 6 of these are linked together, and specific examples include a benzene ring, a fluorene ring, a naphthalene ring, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, and a trivalent group derived from a group in which 2 to 6 of these are linked together.

[0287] R 11 The alkyl group is preferably a linear, branched, or cyclic alkyl group having from 1 to 12 carbon atoms, and specific examples include groups derived from methane, ethane, propane, isopropane, butane, isobutane, pentane, hexane, and octane.

[0288] R 11 The group consisting of an alkyl group having 40 or less carbon atoms and an aromatic ring group is preferably a group in which a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms is linked to one or two to six linked aromatic ring groups which are monocyclic or fused rings having 3 to 30 carbon atoms.

[0289] R 12 Specific examples of the aromatic ring group include a benzene ring, a fluorene ring, a naphthalene ring, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, and a divalent group derived from a linked ring having 30 or less carbon atoms formed by linking these rings.

[0290] R 12 Specific examples of the alkyl group include divalent groups derived from methane, ethane, propane, isopropane, butane, isobutane, pentane, hexane, and octane.

[0291] Ar 31 Specific examples of the aromatic ring group include a benzene ring, a fluorene ring, a naphthalene ring, a carbazole ring, a dibenzofuran ring, a dibenzothiophene ring, and a monovalent group derived from a linked ring having 30 or less carbon atoms formed by linking these rings.

[0292] Preferred examples of the structure of formula (62) include the following structures, where R 11 The benzene ring or fluorene ring in the main chain of the following structure, which is a partial structure of the above, may further have a substituent.

[0293] [ka]

[0294] Ar 31 Examples of the crosslinking group include groups derived from a benzocyclobutene ring, a naphthocyclobutene ring or an oxetane ring, a vinyl group, an acrylic group, etc. In view of the stability of the compound, groups derived from a benzocyclobutene ring or a naphthocyclobutene ring are preferred.

[0295] [ka]

[0296] In the above formula (63), x and y represent integers of 0 or more. 21 , Ar 23 each independently represents a divalent aromatic ring group, and these groups may have a substituent. 22 represents a monovalent aromatic ring group which may have a substituent, R 13 represents an alkyl group, an aromatic ring group, or a divalent group consisting of an alkyl group and an aromatic ring group, which may have a substituent. Ar 32 represents a monovalent aromatic ring group or a monovalent bridging group, and these groups may have a substituent. An asterisk (*) indicates the bonding position to the nitrogen atom in formula (61). Ar 21 , Ar 23 Examples of aromatic ring groups include Ar 11 , Ar 12 , Ar 14 This is the same as in the case of

[0297] Ar 22 , Ar 32 Examples of the aromatic ring group include a single ring, 2 to 6 condensed rings, and groups in which two or more of these aromatic rings are linked together. Specific examples include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzpyrene ring, a chrysene ring, a triphenylene ring, an acenaphthene ring, a fluoranthene ring, a fluorene ring, a biphenyl group, a terphenyl group, a quaterphenyl group, a furan ring, a benzofuran ring, a thiophene ring, a benzothiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxadiazole ring, an indole ring, a carbazole ring, a pyrroloimidazole ring, a pyrrolopyrene ... Examples of suitable monovalent groups include a pyrazole ring, a pyrrolopyrrole ring, a thienopyrrole ring, a thienothiophene ring, a furopyrrole ring, a furofuran ring, a thienofuran ring, a benzisoxazole ring, a benzisothiazole ring, a benzimidazole ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinoxaline ring, a phenanthridine ring, a benzimidazole ring, a perimidine ring, a quinazoline ring, a quinazolinone ring, or an azulene ring. Among these, a monovalent group derived from a benzene ring, a naphthalene ring, a fluorene ring, a pyridine ring, or a carbazole ring, or a biphenyl group, is preferred because they efficiently delocalize negative charges and are excellent in stability and heat resistance.

[0298] R 13 Examples of the alkyl group or aromatic ring group include R 12 is the same as:

[0299] Ar 32 The crosslinking group is not particularly limited, but preferred examples include groups derived from a benzocyclobutene ring, a naphthocyclobutene ring or an oxetane ring, a vinyl group, an acrylic group, and the like.

[0300] The above Ar 11 ~Ar 14 , R 11 ~R 13 , Ar 21 ~Ar 23 , Ar 31 ~Ar 32 , Q 11 , Q 12 Each of the above may further have a substituent, provided that it does not contradict the spirit of the present invention. The molecular weight of the substituent is preferably 400 or less, and more preferably 250 or less. The type of substituent is not particularly limited, and examples include one or more types selected from the following substituent group W.

[0301] Substituent group W: alkyl groups having 1 or more, preferably 10 or less, and more preferably 8 or less carbon atoms, such as a methyl group or an ethyl group; alkenyl groups having 2 or more, preferably 11 or less, and more preferably 5 or less carbon atoms, such as a vinyl group; alkynyl groups having 2 or more, preferably 11 or less, and more preferably 5 or less carbon atoms, such as an ethynyl group; alkoxy groups having 1 or more, preferably 10 or less, and more preferably 6 or less carbon atoms, such as a methoxy group or an ethoxy group; and phenoxy groups, naphthoxy groups, pyridyloxy groups, and the like, having 4 or more, preferably 5 or more, preferably 25 or less, and more preferably 4 or more carbon atoms. alkoxycarbonyl groups having 2 or more, preferably 11 or less, and more preferably 7 or less carbon atoms, such as a methoxycarbonyl group or an ethoxycarbonyl group; dialkylamino groups having 2 or more, preferably 20 or less, and more preferably 12 or less carbon atoms, such as a dimethylamino group or a diethylamino group; diarylamino groups having 10 or more, preferably 12 or more, preferably 30 or less, and more preferably 22 or less carbon atoms, such as a diphenylamino group, a ditolylamino group or an N-carbazolyl group; and phenylmethylamino groups having 6 or more carbon atoms. arylalkylamino groups, more preferably 7 or more and preferably 25 or less, and more preferably 17 or less; acyl groups, such as an acetyl group or a benzoyl group, having 2 or more carbon atoms, preferably 10 or less, and more preferably 7 or less; halogen atoms, such as a fluorine atom or a chlorine atom; haloalkyl groups, such as a trifluoromethyl group, having 1 or more carbon atoms, preferably 8 or less, and more preferably 4 or less; alkylthio groups, such as a methylthio group or an ethylthio group, having 1 or more carbon atoms, preferably 10 or less, and more preferably 6 or less; phenylthio group, naphthylthio group, pyridylthio group, and the like. arylthio groups having 4 or more carbon atoms, preferably 5 or more and 25 or less, and more preferably 14 or less; silyl groups having 2 or more carbon atoms, preferably 3 or more and 33 or less, and more preferably 26 or less, such as a trimethylsilyl group or a triphenylsilyl group; siloxy groups having 2 or more carbon atoms, preferably 3 or more and 33 or less, and more preferably 26 or less, such as a trimethylsiloxy group or a triphenylsiloxy group; cyano groups; aromatic hydrocarbon groups having 6 or more carbon atoms, preferably 30 or less, and more preferably 18 or less, such as a phenyl group or a naphthyl group;Aromatic heterocyclic groups having 3 or more, preferably 4 or more, and preferably 28 or less, and more preferably 17 or less carbon atoms, such as a thienyl group or a pyridyl group;

[0302] Of the above substituent group W, alkyl groups or alkoxy groups are preferred from the viewpoint of improving solubility, and aromatic hydrocarbon groups or aromatic heterocyclic groups are preferred from the viewpoint of charge transport properties and stability.

[0303] In particular, among polymer compounds having a repeating unit represented by formula (61), a polymer compound having a repeating unit represented by the following formula (64) is preferred because it has extremely high hole injection and transport properties.

[0304] [ka]

[0305] In the above formula (64), Y′ represents a divalent aromatic hydrocarbon group which may have a substituent, or a divalent aromatic heterocyclic group which may have a substituent, and R 21 ~R 25 R each independently represents an arbitrary substituent. 21 ~R 25 Specific examples of the substituent are the same as those described in the above [Substituent Group W]. s and t each independently represent an integer of 0 or more and 5 or less. u, v, and w each independently represent an integer of 0 or more and 4 or less.

[0306] Preferred examples of the aromatic tertiary amine polymer compound include polymer compounds containing repeating units represented by the following formula (65) and / or formula (66).

[0307] [ka]

[0308] In the above formula (65) and formula (66), Ar 45 , Ar 47 and Ar 48 each independently represents a monovalent aromatic hydrocarbon group which may have a substituent or a monovalent aromatic heterocyclic group which may have a substituent. 44 and Ar 46 each independently represents a divalent aromatic hydrocarbon group which may have a substituent, or a divalent aromatic heterocyclic group which may have a substituent. R 41 ~R 43 Each independently represents a hydrogen atom or an arbitrary substituent.

[0309] Ar 45 , Ar 47 and Ar 48 Specific examples, preferred examples, examples of the substituents which may be possessed, and preferred examples of the substituents are Ar 22 is the same as Ar 44 and Ar 46 Specific examples, preferred examples, examples of the substituents which may be possessed, and preferred examples of the substituents are Ar 11 , Ar 12 and Ar 14 Similar to R 41 ~R 43 is preferably a hydrogen atom or a substituent described in the above-mentioned [Substituent group W], and more preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, an aromatic hydrocarbon group, or an aromatic heterocyclic group.

[0310] Preferred specific examples of the repeating units represented by formula (65) and formula (66) that can be used in the present invention are listed below, but the present invention is not limited to these.

[0311] [ka]

[0312] (Electron-accepting compounds) The composition for forming a hole injection layer preferably contains an electron accepting compound as a constituent material of the hole injection layer 3 . The electron-accepting compound is preferably a compound having oxidizing power and the ability to accept one electron from the hole-transporting material. Specifically, the electron-accepting compound is preferably a compound having an electron affinity of 4.0 eV or more, more preferably 5.0 eV or more.

[0313] Examples of such electron-accepting compounds include one or more compounds selected from the group consisting of triarylboron compounds, metal halides, Lewis acids, organic acids, onium salts, salts of arylamines and metal halides, and salts of arylamines and Lewis acids. More specifically, examples of the electron-accepting compound include onium salts substituted with organic groups, such as 4-isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate and triphenylsulfonium tetrafluoroborate (WO 2005 / 089024, WO 2017 / 164268); high-valent inorganic compounds, such as iron(III) chloride (JP 11-251067 A) and ammonium peroxodisulfate; cyano compounds, such as tetracyanoethylene; and aromatic boron compounds, such as tris(pentafluorophenyl)borane (JP 2003-31365 A); fullerene derivatives; iodine; and sulfonate ions, such as polystyrene sulfonate ions, alkylbenzene sulfonate ions, and camphorsulfonate ions.

[0314] The electron-accepting compound can improve the conductivity of the hole-injection layer 3 by oxidizing the hole-transporting material.

[0315] (Other constituent materials) The material of the hole injection layer 3 may contain other components in addition to the hole transport material and electron accepting compound described above, as long as the effects of the present invention are not significantly impaired.

[0316] <Hole transport layer 4> The hole transport layer 4 is a layer that transports holes from the anode 2 to the light-emitting layer 5. The hole transport layer 4 is not an essential layer for the organic electroluminescent device according to the embodiment of the present invention. However, when the hole transport layer 4 is provided, the hole transport layer 4 is usually formed on the hole injection layer 3 when the hole injection layer 3 is present, or on the anode 2 when the hole injection layer 3 is not present. The method for forming the hole transport layer 4 is not particularly limited and may be a vacuum deposition method or a wet film formation method, but is preferably formed by a wet film formation method from the viewpoint of reducing dark spots.

[0317] The material forming the hole transport layer 4 is preferably a material that has high hole transport properties and can efficiently transport injected holes. To this end, the material forming the hole transport layer 4 preferably has a low ionization potential, high transparency to visible light, high hole mobility, excellent stability, and is unlikely to generate impurities that act as traps during production or use. In many cases, the hole transport layer 4 is in contact with the light-emitting layer 5, and therefore it is preferable that the hole transport layer 4 does not quench the light emission from the light-emitting layer 5 or form exciplexes with the light-emitting layer 5, thereby reducing efficiency.

[0318] The material of the hole transport layer 4 may be any material that has been conventionally used as a constituent material of the hole transport layer 4. Examples of the material of the hole transport layer 4 include arylamine derivatives, fluorene derivatives, spiro derivatives, carbazole derivatives, pyridine derivatives, pyrazine derivatives, pyrimidine derivatives, triazine derivatives, quinoline derivatives, phenanthroline derivatives, phthalocyanine derivatives, porphyrin derivatives, silole derivatives, oligothiophene derivatives, condensed polycyclic aromatic derivatives, and metal complexes.

[0319] Examples of materials for the hole transport layer 4 include polyvinylcarbazole derivatives, polyarylamine derivatives, polyvinyltriphenylamine derivatives, polyfluorene derivatives, polyarylene derivatives, polyarylene ether sulfone derivatives containing tetraphenylbenzidine, polyarylene vinylene derivatives, polysiloxane derivatives, polythiophene derivatives, and poly(p-phenylene vinylene) derivatives. These may be alternating copolymers, random polymers, block polymers, or graft copolymers. Furthermore, the material may be a polymer having a branched main chain with three or more terminals, or a so-called dendrimer.

[0320] Among these, polyarylamine derivatives and polyarylene derivatives are preferable as the material for the hole transport layer 4. Specific examples of polyarylamine derivatives and polyarylene derivatives include those described in JP-A-2008-98619. As the polyarylamine derivative, it is preferable to use the aromatic tertiary amine polymer compound.

[0321] When the hole transport layer 4 is formed by a wet film formation method, the layer is wet formed in the same manner as in the formation of the hole injection layer 3, and then dried. The hole transport layer-forming composition contains the hole transport material and an organic solvent. The organic solvent used is the same as that used in the hole injection layer-forming composition. The drying conditions are also the same as those used in forming the hole injection layer 3.

[0322] When the hole transport layer 4 is formed by vacuum deposition, the film formation conditions are the same as those for forming the hole injection layer 3 described above.

[0323] The thickness of the hole transport layer 4 is usually 5 nm or more, preferably 10 nm or more, and usually 300 nm or less, preferably 200 nm or less, taking into consideration factors such as penetration of the low molecular weight material in the light emitting layer and swelling of the hole transport material.

[0324] <Light-emitting layer 5> The light-emitting layer 5 is a layer that serves as a main light source when excited by recombination of holes injected from the anode 2 and electrons injected from the cathode 7 between the electrodes to which an electric field is applied. The light-emitting layer 5 is usually formed on the hole-transporting layer 4 when the hole-transporting layer 4 is present, on the hole-injecting layer 3 when the hole-transporting layer 4 is not present but the hole-injecting layer 3 is present, or on the anode 2 when neither the hole-transporting layer 4 nor the hole-injecting layer 3 is present.

[0325] The light-emitting layer 5 contains at least a material having light-emitting properties (light-emitting material), and preferably contains one or more host materials. As described above, the light-emitting layer 5 of the organic electroluminescent device according to the embodiment of the present invention is preferably formed using the composition according to this embodiment.

[0326] An inkjet method is preferred as a wet film formation method for forming the light-emitting layer 5. Forming the light-emitting layer 5 by the inkjet method is preferred because it enables the formation of a film by the inkjet method in succession to the organic layer formed using the layer-forming composition according to an embodiment of the present invention.

[0327] The thickness of the light-emitting layer 5 is not limited and is usually 5 nm or more, preferably 10 nm or more, and usually 100 nm or less, preferably 90 nm or less.

[0328] <Hole-blocking layer> A hole-blocking layer may be provided between the light-emitting layer 5 and the electron injection layer described below. The hole-blocking layer is a layer in the electron-transporting layer that also plays a role in blocking holes migrating from the anode 2 from reaching the cathode 7. The hole-blocking layer is a layer laminated on the light-emitting layer 5 so as to be in contact with the interface of the light-emitting layer 5 on the cathode 7 side.

[0329] The hole blocking layer has the role of preventing holes migrating from the anode 2 from reaching the cathode 7 and the role of efficiently transporting electrons injected from the cathode 7 toward the light-emitting layer 5 .

[0330] The properties required for the material that constitutes the hole-blocking layer include high electron mobility and low hole mobility, a large energy gap (difference between HOMO and LUMO), and a high excited triplet energy level (T1). Examples of materials for hole-blocking layers that satisfy these conditions include mixed ligand complexes such as bis(2-methyl-8-quinolinolato)(phenolato)aluminum and bis(2-methyl-8-quinolinolato)(triphenylsilanolato)aluminum; metal complexes such as bis(2-methyl-8-quinolinolato)aluminum-μ-oxo-bis-(2-methyl-8-quinolinolato)aluminum binuclear metal complex; styryl compounds such as distyrylbiphenyl derivatives (Japanese Patent Laid-Open No. 11-242996); triazole derivatives such as 3-(4-biphenylyl)-4-phenyl-5(4-tert-butylphenyl)-1,2,4-triazole (Japanese Patent Laid-Open No. 7-41759); and phenanthroline derivatives such as bathocuproine (Japanese Patent Laid-Open No. 10-79297). Furthermore, compounds having at least one pyridine ring substituted at the 2-, 4-, and 6-positions, as described in WO 2005 / 022962, are also preferred as materials for the hole-blocking layer.

[0331] The thickness of the hole blocking layer is not limited and is generally 0.3 nm or more, preferably 0.5 nm or more, and generally 100 nm or less, preferably 50 nm or less.

[0332] <Electron transport layer 6> The electron transport layer 6 is a layer provided between the light emitting layer 5 and the cathode 7 for transporting electrons. As the electron transporting compound for the electron transport layer 6, a compound is usually used that has a high efficiency of injecting electrons from the cathode 7 or an adjacent layer on the cathode 7 side, and that has high electron mobility and can efficiently transport the injected electrons. Examples of compounds that satisfy these conditions include metal complexes such as aluminum complexes and lithium complexes of 8-hydroxyquinoline (Japanese Patent Laid-Open No. 59-194393), metal complexes of 10-hydroxybenzo[h]quinoline, oxadiazole derivatives, distyrylbiphenyl derivatives, silole derivatives, 3-hydroxyflavone metal complexes, 5-hydroxyflavone metal complexes, benzoxazole metal complexes, benzothiazole metal complexes, trisbenzimidazolylbenzene (U.S. Pat. No. 5,645,948), quinoxaline compounds (Japanese Patent Laid-Open No. 6-207169), phenanthroline derivatives (Japanese Patent Laid-Open No. 5-331459), 2-tert-butyl-9,10-N,N'-dicyanoanthraquinone diimine, triazine compound derivatives, and perylene tetracarboxylic acid imide compound derivatives.

[0333] In the method for producing an organic electroluminescent device according to an embodiment of the present invention, it is preferable that the hole blocking layer is not present and the layer in contact with the cathode 7 side of the light emitting layer 5 is the electron transport layer 6.

[0334] The thickness of the electron transport layer 6 is arbitrary as long as it does not significantly impair the effects of the present invention. The thickness of the electron transport layer 6 is usually 1 nm or more, preferably 5 nm or more, and usually 300 nm or less, preferably 100 nm or less.

[0335] <Electron injection layer> In order to efficiently inject electrons injected from the cathode 7 into the light-emitting layer 5, an electron injection layer may be provided between the electron transport layer 6 and the cathode 7 described below. The electron injection layer is made of an inorganic salt or the like. Examples of materials for the electron injection layer include lithium fluoride (LiF), magnesium fluoride (MgF), lithium oxide (LiO), and cesium (II) carbonate (CsCO) (see Applied Physics Letters, 1997, Vol. 70, p. 152; JP-A-10-74586; IEEE Transactions on Electron Devices, 1997, Vol. 44, p. 1245; SID 04 Digest, p. 154, etc.).

[0336] Since the electron injection layer often does not have charge transport properties, it is preferably used as an ultrathin film in order to efficiently inject electrons, and the film thickness is usually 0.1 nm or more, preferably 5 nm or less.

[0337] <Cathode 7> The cathode 7 is an electrode that serves to inject electrons into the layer on the light-emitting layer 5 side.

[0338] Examples of materials for the cathode 7 include metals such as aluminum, gold, silver, nickel, palladium, and platinum; metal oxides such as indium and / or tin oxide; metal halides such as copper iodide; carbon black; and conductive polymers such as poly(3-methylthiophene), polypyrrole, and polyaniline. Among these, metals with a low work function are preferred for efficient electron injection, and suitable metals such as tin, magnesium, indium, calcium, aluminum, and silver, or alloys thereof, are used. Specific examples include low-work-function alloy electrodes such as magnesium-silver alloys, magnesium-indium alloys, and aluminum-lithium alloys. The cathode 7 may be made of one material alone or two or more materials in any combination and ratio.

[0339] The thickness of the cathode 7 varies depending on the required transparency. When transparency is required, it is preferable that the visible light transmittance is usually 60% or more, preferably 80% or more. In this case, the thickness of the cathode 7 is usually 5 nm or more, preferably 10 nm or more, and usually 1000 nm or less, preferably 500 nm or less. When opaqueness is sufficient, the thickness of the cathode 7 is arbitrary, and the cathode may be the same thickness as the substrate.

[0340] It is also possible to layer a different conductive material on top of the cathode 7 . For example, in order to protect a cathode made of a metal with a low work function, such as an alkali metal such as sodium or cesium, or an alkaline earth metal such as barium or calcium, it is preferable to further laminate a metal layer having a high work function and being stable against the atmosphere on the cathode, since this increases the stability of the element. For this purpose, metals such as aluminum, silver, copper, nickel, chromium, gold, platinum, etc. These materials may be used alone or in any combination and ratio of two or more.

[0341] <Other layers> The organic electroluminescent device according to the embodiment of the present invention may have other configurations within the scope of the gist thereof. For example, as long as the performance is not impaired, any layer other than the layers described above may be present between the anode 2 and the cathode 7, and any layer not required among the layers described above may be omitted.

[0342] In the layer structure described above, the components other than the substrate may be stacked in the reverse order. For example, in the layer structure shown in Fig. 1, the other components may be provided on the substrate 1 in the following order: cathode 7, electron transport layer 6, light-emitting layer 5, hole transport layer 4, hole injection layer 3, and anode 2.

[0343] The organic electroluminescent device according to the embodiment of the present invention may be configured as a single organic electroluminescent device, or may be applied to a configuration in which a plurality of organic electroluminescent devices are arranged in an array, or may be applied to a configuration in which anodes and cathodes are arranged in an XY matrix.

[0344] Each of the above-described layers may contain components other than those described as materials.

[0345] [Method of manufacturing organic electroluminescent device] The method for manufacturing the organic electroluminescent device according to this embodiment is not particularly limited as long as the above-described composition is used. For example, the method for manufacturing the organic electroluminescent device according to this embodiment may include a manufacturing method including a step of forming a light-emitting layer by a wet film-forming method using the above-described composition.

[0346] [Display device] The display device according to this embodiment has the organic electroluminescent device as described above. There are no particular limitations on the type or structure of the display device, and it can be assembled using the organic electroluminescent device according to this embodiment in accordance with a conventional method. For example, the display device according to this embodiment can be formed by a method such as that described in "Organic EL Display" (Ohmsha, published August 20, 2004, by Tokito Shizuo, Adachi Chinaya, and Murata Hideyuki). [Example]

[0347] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention. The values ​​of various conditions and evaluation results in the following examples are meant as preferred upper or lower limit values ​​in the embodiments of the present invention, and a preferred range may be defined by a combination of the above-mentioned upper or lower limit value and the value of the following examples or values ​​between the examples.

[0348] [ka]

[0349] The above compound 1 was synthesized according to the method described in International Publication No. 2022 / 255403, the above compound 2 was synthesized according to the method described in ACS Applied Materials & Interfaces (2018), 10(41), 35420-35429, and the above compound 3 was synthesized according to the method described in Korean Patent Publication No. 10-2015-0141047.

[0350] For Compounds 1 to 3, the number of nitrogen atoms in the compound per 1000 molecular weight is shown in Table 1. Compound 1 satisfies formula (I) and corresponds to Compound A. Compound 2 does not satisfy formula (I) or formula (II) and corresponds to neither Compound A nor Compound B. Compound 3 satisfies formula (II) and corresponds to Compound B.

[0351] [Table 1]

[0352] [Fabrication and Performance Evaluation of Organic Electroluminescent Devices] [Example I-1] An organic electroluminescent device was fabricated in the following manner. A 50-nm-thick indium tin oxide (ITO) transparent conductive film (Geomatec, sputter-deposited) was deposited on a glass substrate and patterned into 2-mm-wide stripes using standard photolithography and hydrochloric acid etching to form the anode. The substrate with the ITO pattern formed was then ultrasonically cleaned with a surfactant solution, rinsed with ultrapure water, ultrasonically cleaned with ultrapure water, and rinsed with ultrapure water again, followed by drying with compressed air and finally cleaning with ultraviolet ozone.

[0353] A composition for forming a hole injection layer was prepared by dissolving 3.0 mass% of a hole transporting polymer compound having a repeating structure of the following formula (P-1) and 0.6 mass% of an electron accepting compound (HI-1) in ethyl benzoate.

[0354] [ka]

[0355] This composition for forming a hole injection layer was spin-coated onto the substrate in the atmosphere and dried on a hot plate in the atmosphere at 240° C. for 30 minutes to form a uniform thin film with a thickness of 40 nm, which was used as a hole injection layer.

[0356] Next, a charge transporting polymer compound having a repeating structure of the following formula (HT-1) was dissolved in 1,3,5-trimethylbenzene to prepare a 2.0 mass % solution. This solution was spin-coated in a nitrogen glove box onto the substrate on which the hole injection layer had been formed, and dried on a hot plate in the nitrogen glove box at 230°C for 30 minutes to form a uniform thin film with a thickness of 40 nm, which served as a hole transport layer.

[0357] [ka]

[0358] Subsequently, as materials for the light-emitting layer, 2.5 mass % of Compound 1, 2.5 mass % of Compound 3, and 1 mass % of the following compound (D-1) were dissolved in cyclohexylbenzene to prepare a composition for forming the light-emitting layer.

[0359] [ka]

[0360] The composition for forming the light-emitting layer was spin-coated onto the substrate on which the hole transport layer had been formed in a nitrogen glove box, and dried on a hot plate in the nitrogen glove box at 120°C for 20 minutes to form a uniform thin film with a thickness of 60 nm, which was used as the light-emitting layer.

[0361] The substrate on which the light-emitting layer had been formed was placed in a vacuum deposition device, and the inside of the device was heated to 2 × 10 -4 The pressure was evacuated until it reached a pressure of 0.1 Pa or less. Next, the following compound (ET-1) and 8-hydroxyquinolinolatolithium were co-deposited on the light-emitting layer in a thickness ratio of 2:3 by vacuum deposition to form an electron transport layer with a thickness of 30 nm.

[0362] [ka]

[0363] Next, a 2 mm wide striped shadow mask was attached to the substrate as a mask for cathode deposition so that it was perpendicular to the ITO stripes of the anode, and aluminum was heated using a molybdenum boat to form an 80 nm thick aluminum layer, forming the cathode.

[0364] In this manner, an organic electroluminescent device having a light-emitting area measuring 2 mm×2 mm was obtained.

[0365] [Comparative example I-1] An organic electroluminescent device was produced in the same manner as in Example I-1, except that Compound 2 was used instead of Compound 1 as the material for the light-emitting layer.

[0366] [Element evaluation] The organic electroluminescent devices obtained in Example I-1 and Comparative Example I-1 were tested at a luminance of 1,000 cd / m 2 The current efficiency (cd / A) and external quantum efficiency (%) were measured when the device was lit at 15 mA / cm. 2 The time (LT95) until the luminance decreased to 95% of the initial luminance when the element was continuously energized at a current density of 1000 kJ / s was measured. The results of these measurements are shown in Table 2. In Table 2, the values ​​for Example I-1 are relative values, with the value for Comparative Example I-1 being set at 1. The results in Table 2 show that the organic electroluminescent device using the composition according to the embodiment of the present invention has high luminous efficiency and long operating life.

[0367] [Table 2] [Industrial Applicability]

[0368] The composition according to the embodiment of the present invention makes it possible to prepare an organic electroluminescent device having higher luminous efficiency and longer operating life than conventional ones. [Explanation of symbols]

[0369] 1 board 2 Anode 3. Hole injection layer 4. Hole transport layer 5. Light-emitting layer 6 Electron transport layer 7 Cathode 8. Organic electroluminescent device

Claims

1. A composition for an organic electroluminescent device, Compound A satisfying the following formula (I); and a compound B satisfying the following formula (II): The composition, wherein the compound A and the compound B each have two or more carbazolyl groups. 4.20<N Ａ <5.80 Formula (I) 1.00<N Ｂ <2.90 Formula (II) In formula (I), N Ａ represents the number of nitrogen atoms in compound A per 1000 molecular weight. In formula (II), N Ｂ represents the number of nitrogen atoms in compound B per 1000 molecular weight.

2. The composition according to claim 1 , wherein the compound A is represented by the following formula (1): 【Chemical 1】 (In formula (1), W １１ , W １２ and W １３ each independently represents CH or N; W １１ , W １２ and W １３ at least one of which is a nitrogen atom, Xa １１ , Ya １１ , and Za １１ each independently represents a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent, or a divalent aromatic heterocyclic group having 3 to 30 carbon atoms which may have a substituent, Xa １２ , Ya １２ and Za １２ each independently represents a hydrogen atom, an optionally substituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, or an optionally substituted monovalent aromatic heterocyclic group having 3 to 30 carbon atoms, g11, h11, and j11 each independently represent an integer of 0 to 6; At least one of g11, h11, and j11 is an integer of 1 or more, When g11 is an integer of 2 or more, there are a plurality of Xa １１ may be the same or different, When h11 is an integer of 2 or more, there are multiple Ya １１ may be the same or different, If j11 is an integer of 2 or more, there are multiple Za １１ may be the same or different, R １１ represents a hydrogen atom or a substituent, and four R １１ may be the same or different, However, when g11, h11, or j11 is 0, the corresponding Xa １２ , Ya １２ , Za １２ is not a hydrogen atom.)

3. The composition according to claim 2, wherein the compound represented by formula (1) is represented by the following formula (1-1): 【Chemistry 2】 (In formula (1-1), W １１ , W １２ and W １３ each independently represents —CH or a nitrogen atom; W １１ , W １２ and W １３ at least one of which is a nitrogen atom, Xa １１ , Ya １１ , and Za １１ each independently represents an optionally substituted 1,3-phenylene group or an optionally substituted 1,4-phenylene group, Ya １１ and Za １１ at least one of is an optionally substituted 1,3-phenylene group, Xa １２ represents an optionally substituted phenyl group, Ya １２ and Za １２ each independently represents an N-carbazolyl group which may have a substituent; f11 is 1 or 2, g11 is an integer from 0 to 5, h11 is an integer from 0 to 5, j11 is an integer from 0 to 5, R １１ each independently represents a hydrogen atom or a substituent.

4. Ya in the formula (1-1) １１ At least one of Za is a 1,3-phenylene group, １１ The composition of claim 3, wherein at least one of is a 1,3-phenylene group.

5. Xa in the formula (1-1) １１ The composition of claim 3, wherein at least one of is a 1,3-phenylene group.

6. The composition according to claim 1, wherein the compound B is represented by the following formula (240) or the following formula (241): 【Chemistry 3】 (In formula (240), Ar ６１１ , Ar ６１２ each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R ６１１ , R ６１２ each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. G represents a single bond or a divalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. n ６１１ , n ６１２ are each independently an integer of 0 to 4. 【Chemistry 4】 (In formula (241), Ar ６１３ ~Ar ６１５ each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R ６１３ , R ６１４ each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. Each G independently represents a single bond or a divalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. n ６１３ , n ６１４ are each independently an integer of 0 to 4.

7. The composition according to claim 1, wherein the compound B is represented by the following formula (240-1) or the following formula (241-1): 【Chemistry 5】 (In formula (240-1), Ar ６１１ , Ar ６１２ each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R ６１１ , R ６１２ each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. 【Chemistry 6】 (In formula (241-1), Ar ６１３ ~Ar ６１５ each independently represents a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent. R ６１３ , R ６１４ each independently represents a hydrogen atom, a deuterium atom, a halogen atom, or a monovalent aromatic hydrocarbon group having 6 to 50 carbon atoms which may have a substituent.

8. Ar in the formula (240) and the formula (241) ６１１ ~Ar ６１５ The composition according to claim 6 , wherein each of the groups independently represents a monovalent group in which a plurality of benzene rings, which may have a substituent, are linked in a linear or branched manner.

9. R in the formula (240) and the formula (241) ６１１ ~R ６１４ and each independently represent a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms which may have a substituent.

10. The composition of claim 1 further comprising a light-emitting material.

11. The composition according to claim 10 , comprising at least one compound represented by the following formula (3) as the light-emitting material: 【Chemistry 7】 [In formula (3), Ring A1 represents an aromatic hydrocarbon structure which may have a substituent or an aromatic heterocyclic structure which may have a substituent. Ring A2 represents an aromatic heterocyclic structure which may have a substituent. R ２０１ , R ２０２ are each independently a structure represented by formula (b), and "*" represents the bonding position with ring A1 or ring A2. ２０１ , R ２０２ may be the same or different, and R ２０１ , R ２０２ When there are a plurality of each of the groups, they may be the same or different. Ar ２０１ , Ar ２０３ each independently represents an aromatic hydrocarbon structure which may have a substituent, or an aromatic heterocyclic structure which may have a substituent. Ar ２０２ represents an aromatic hydrocarbon structure which may have a substituent, an aromatic heterocyclic structure which may have a substituent, or an aliphatic hydrocarbon structure which may have a substituent. The substituents bonded to ring A1 may be bonded to each other, the substituents bonded to ring A2 may be bonded to each other, or the substituents bonded to ring A1 and the substituents bonded to ring A2 may be bonded to each other to form a ring. B ２０１ -L ２００ -B ２０２ represents an anionic bidentate ligand. ２０１ and B ２０２ Each of L independently represents a carbon atom, an oxygen atom, or a nitrogen atom, and these atoms may be atoms constituting a ring. ２００ is a single bond, or B ２０１ and B ２０２ represents an atomic group that together with B constitutes a bidentate ligand. ２０１ -L ２００ -B ２０２ When there are multiple groups, they may be the same or different. In the formula (3) and the formula (b), i1 and i2 each independently represent an integer of 0 to 12, i3 is Ar ２０２ represents an integer of 0 or more, with the upper limit being the number that can be replaced by i4 is Ar ２０１ represents an integer of 0 or more, with the upper limit being the number that can be replaced by k1 and k2 each independently represent an integer of 0 or greater, the upper limit of which is the number of groups that can be substituted on ring A1 and ring A2; z represents an integer of 1 to 3; M represents a metal atom selected from Groups 7 to 11 of the periodic table.

12. The composition according to claim 1, further comprising at least one compound represented by the following formula (260): 【Chemistry 8】 (In formula (260), Ar ２１ ~Ar ３５ each independently represents a hydrogen atom, a phenyl group which may have a substituent, or a monovalent group in which 2 to 10 phenyl groups which may have a substituent are linked in an unbranched or branched manner.

13. In the formula (260), Ar ２１ , Ar ２５ , Ar ２６ , Ar ３０ , Ar ３１ and Ar ３５ is a hydrogen atom, Ar ２２ ~Ar ２４ , Ar ２７ ~Ar ２９ , and Ar ３２ ~Ar ３４ are each independently a hydrogen atom, an optionally substituted phenyl group, or a structure selected from the following formulas (261-1) to (261-9), each of which optionally has a substituent: 【Chemistry 9】 (In formulas (261-1) to (261-9), * represents the bonding position to the benzene ring in formula (260).)

14. The composition of claim 1 further comprising an organic solvent.

15. A method for producing an organic electroluminescent device, comprising the step of forming a light-emitting layer by a wet film-forming method using the composition according to any one of claims 1 to 14.

16. An organic electroluminescent device having a light-emitting layer formed using the composition according to any one of claims 1 to 14.

17. A display device comprising the organic electroluminescent device according to claim 16.

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