Organic electroluminescent element

Abstract

The present application aims at providing a material for an organic EL element having excellent hole injection and transport properties, electron blocking ability, stability in a thin film state, and durability, and further, by combining the material with various materials for an organic EL element having excellent hole and electron injection and transport properties, electron blocking ability, stability in a thin film state, and durability so that the characteristics of each material can be effectively exhibited, an organic EL element having high efficiency, low driving voltage, and long life is provided. The arylamine compound having a specific structure in the present application is excellent in hole injection and transport ability, stability, and durability of a thin film, and thus, by selecting the arylamine compound having a specific structure as a material for a hole transport layer, holes injected from the anode side can be efficiently transported. Further, various organic EL elements combined with an electron transport material having a specific structure and the like exhibit good element characteristics.

Description

Technical Field

[0001] This invention relates to organic electroluminescent elements as self-emissive elements suitable for various display devices, and more specifically, to organic electroluminescent elements (hereinafter referred to as organic EL elements) using specific arylamine compounds. Background Technology

[0002] Organic EL elements are self-emissive, therefore they are brighter and have better visibility than liquid crystal elements, enabling vivid displays, and thus have been the subject of active research.

[0003] In 1987, CWTang et al. of Eastman Kodak developed a layered structure element that distributed various functions among different materials, thus making organic EL elements using organic materials practical devices. They layered an electron-transferring phosphor with an organic material that could transport holes, and injected the charges of both into the phosphor layer to make it emit light, thereby achieving 1000 cd / m² with a voltage below 10V. 2 The above high brightness (see, for example, Patent Document 1 and Patent Document 2).

[0004] To date, numerous improvements have been made to make organic EL devices practical, further subdividing the various functions of the stacked structure to create electroluminescent devices with an anode, hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, and cathode sequentially disposed on a substrate, thereby achieving high efficiency and durability (see, for example, Non-Patent Literature 1).

[0005] In addition, with the aim of further improving luminescence efficiency, the utilization of triplet excitons was explored, and the utilization of phosphorescent compounds was studied (see, for example, non-patent literature 2).

[0006] Furthermore, devices utilizing thermally activated delayed fluorescence (TADF) have also been developed. In 2011, Adachi et al. from Kyushu University achieved an external quantum efficiency of 5.3% using a device made of thermally activated delayed fluorescence material (see, for example, Non-Patent Literature 3).

[0007] Regarding the light-emitting layer, it can also be fabricated by doping a fluorescent compound, a phosphorescent compound, or a material that emits delayed fluorescence into a charge-transporting compound generally referred to as the host material. As described in the aforementioned non-patent literature, the selection of organic materials in organic EL elements has a significant impact on various characteristics of the element, such as efficiency and durability (see, for example, non-patent literatures 1-3).

[0008] In organic electron microscopy (EL) devices, light emission is achieved by the recombination of charges injected from the two electrodes in the light-emitting layer. Efficiently delivering both holes and electrons to the light-emitting layer is crucial, requiring devices with excellent carrier balance. Furthermore, improving hole injection capability and electron blocking capability increases the probability of hole-electron recombination. By confining the excitons generated within the light-emitting layer, high luminous efficiency can be achieved. Therefore, hole transport materials play a vital role, and the search seeks hole transport materials with high hole injection capability, high hole mobility, high electron blocking capability, and consequently, high electron durability.

[0009] Furthermore, the heat resistance and amorphous properties of the material are also important factors regarding the lifespan of components. For materials with low heat resistance, thermal decomposition and material degradation occur even at low temperatures due to the heat generated during component operation. For materials with low amorphous properties, thin film crystallization occurs even in a short time, leading to component degradation. Therefore, materials with high heat resistance and good amorphous properties are sought for use.

[0010] As hole transport materials currently used in organic EL devices, N,N'-diphenyl-N,N'-bis(α-naphthyl)benzidine (NPD) and various aromatic amine derivatives are known (see, for example, Patent Documents 1 and 2). NPD has good hole transport capabilities, but its glass transition temperature (Tg), an indicator of heat resistance, is as low as 96°C, and crystallization occurs under high-temperature conditions, leading to a decrease in device properties (see, for example, Non-Patent Document 4).

[0011] Furthermore, among the aromatic amine derivatives described in the aforementioned patent documents, the known hole mobility is 10. -3 cm 2 Compounds with excellent mobility of / Vs or higher (see, for example, Patent Documents 1 and 2) exhibit insufficient electron blocking properties, resulting in some electrons passing through the luminescent layer and thus preventing the expectation of improved luminous efficiency. For further increases in efficiency, materials with higher electron blocking properties, more stable films, and higher heat resistance are required. Additionally, there are reports of highly durable aromatic amine derivatives (see, for example, Patent Document 3) being used as charge transport materials in electrophotographic photosensitive elements, but there are no examples of their use as organic EL elements.

[0012] As compounds that improve properties such as heat resistance and hole injection, arylamine compounds with substituted carbazole structures have been proposed (for example, see Patent Documents 4 and 5). For devices using these compounds in hole injection layers or hole transport layers, although improvements in heat resistance and luminous efficiency have been achieved, they are not yet sufficient. Further reductions in driving voltage and further increases in luminous efficiency are sought.

[0013] In order to improve the characteristics of organic EL devices and increase the yield of device fabrication, we seek to create devices with high efficiency of hole and electron recombination, high luminous efficiency, low driving voltage, and long life by combining materials with excellent hole and electron injection and transport performance, thin film stability, and durability.

[0014] In addition, in order to improve the device characteristics of organic EL devices, we seek to achieve high efficiency, low driving voltage and long life by combining materials with excellent hole and electron injection and transport performance, thin film stability and durability.

[0015] Existing technical documents

[0016] Patent documents

[0017] Patent Document 1: Japanese Patent Application Publication No. 8-048656

[0018] Patent Document 2: Japanese Patent No. 3194657

[0019] Patent Document 3: Japanese Patent No. 4943840

[0020] Patent Document 4: Japanese Patent Application Publication No. 2006-151979

[0021] Patent Document 5: International Publication No. 2008 / 62636

[0022] Patent Document 6: International Publication No. 2014 / 009310

[0023] Non-patent literature

[0024] Non-patent literature 1: Proceedings of the 9th Workshop of the Chinese Society of Applied Physics, pp. 55-61 (2001)

[0025] Non-patent literature 2: Proceedings of the 9th Workshop of the Chinese Society of Applied Physics, pp. 23-31 (2001)

[0026] Non-patent literature 3: Appl. Phys. Let., 98, 083302 (2011)

[0027] Non-patent literature 4: Proceedings of the Third Regular Meeting of the Organic EL Symposium, pp. 13-14 (2006) Summary of the Invention

[0028] The problem that the invention aims to solve

[0029] The object of this invention is to provide a material for organic EL devices that exhibits excellent hole injection and transport performance, electron blocking capability, stability in the thin film state, and durability, as a material for high-efficiency and high-durability organic EL devices. Furthermore, by combining this material with various other materials for organic EL devices that exhibit excellent hole and electron injection and transport performance, electron blocking capability, stability in the thin film state, and durability, the characteristics of each material can be effectively utilized, thereby providing a high-efficiency, low-drive-voltage, and long-life organic EL device.

[0030] The physical properties that the organic compound to be provided by this invention should possess include: (1) good hole injection characteristics; (2) high hole mobility; (3) excellent electron blocking ability; (4) stable thin film state; and (5) excellent heat resistance. Furthermore, the physical properties that the organic EL element to be provided by this invention should possess include: (1) high luminous efficiency and power efficiency; (2) low luminous emission start voltage; (3) low practical driving voltage; and (4) long lifetime.

[0031] Methods for solving problems

[0032] Therefore, in order to achieve the above-mentioned objectives, the inventors focused on the superior hole injection and transport capabilities, thin film stability, and durability of arylamine compounds with specific structures. Various arylamine compounds were selected, organic EL devices were fabricated, and the characteristics of these devices were thoroughly evaluated. As a result, the inventors gained the following insights: if an arylamine compound with a specific structure is selected as the material for the hole transport layer, holes injected from the anode side can be transported with high efficiency. Furthermore, various organic EL devices combining luminescent materials with specific structures were fabricated, and the characteristics of these devices were thoroughly evaluated. As a result, the present invention was completed.

[0033] That is, according to the present invention, the following organic EL element is provided.

[0034] 1) An organic EL element having at least an anode, a hole transport layer, a light-emitting layer, an electron transport layer and a cathode in sequence, characterized in that the hole transport layer contains an arylamine compound represented by the following general formula (1).

[0035] [Chemistry 1]

[0036]

[0037] (In the formula, R1 and R2 represent deuterium atom, fluorine atom, chlorine atom, cyano, nitro, a straight-chain or branched alkyl group with 1 to 6 carbon atoms that may have substituents, a cycloalkyl group with 5 to 10 carbon atoms that may have substituents, a straight-chain or branched alkenyl group with 2 to 6 carbon atoms that may have substituents, a straight-chain or branched alkoxy group with 1 to 6 carbon atoms that may have substituents, a cycloalkoxy group with 5 to 10 carbon atoms that may have substituents, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group. R3 represents hydrogen atom, deuterium atom, fluorine atom, chlorine atom, cyano, nitro, a straight-chain or branched alkyl group with 1 to 6 carbon atoms that may have substituents, a straight-chain or branched alkyl group with 1 to 6 carbon atoms that may have substituents, a straight-chain or branched alkyl group with 5 to 10 carbon atoms that may have substituents, a substituted or unsubstituted aromatic hydrocarbon group ... The following groups are considered as follows: cycloalkyl groups with 5 to 10 carbon atoms; alkenyl groups with 2 to 6 carbon atoms that may have substituents; alkoxy groups with 1 to 6 carbon atoms that may have substituents; cycloalkoxy groups with 5 to 10 carbon atoms that may have substituents; substituted or unsubstituted aromatic hydrocarbon groups; substituted or unsubstituted aromatic heterocyclic groups; substituted or unsubstituted fused polycyclic aromatic groups; or substituted or unsubstituted aryloxy groups. A1 represents a divalent group of a substituted or unsubstituted aromatic hydrocarbon, a divalent group of a substituted or unsubstituted aromatic heterocycle, or a divalent group of a substituted or unsubstituted fused polycyclic aromatic group. Ar1 to Ar3 represent substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups, or substituted or unsubstituted fused polycyclic aromatic groups. r1 and r2 represent integers from 0 to 4.

[0038] 2) The organic EL element described in 1) above is characterized in that the hole transport layer is a two-layer structure of a first hole transport layer and a second hole transport layer, wherein the second hole transport layer contains the arylamine compound represented by the general formula (1).

[0039] 3) The organic EL element described in 1) or 2) above is characterized in that the arylamine compound represented by general formula (1) is an arylamine compound represented by the following general formula (1a).

[0040] [Chemistry 2]

[0041]

[0042] (In the formula, A1 and Ar1 to Ar3 are defined as in the general formula (1).)

[0043] 4) The organic EL element described in any one of 1) to 3) above, characterized in that Ar3 in the above general formula (1) or general formula (1a) is a substituted or unsubstituted phenyl.

[0044] 5) The organic EL element described in any one of 1) to 4) above, characterized in that, in the above general formula (1) or general formula (1a), A1 is a divalent group (phenylene) generated by removing two hydrogen atoms from benzene, whether substituted or unsubstituted.

[0045] 6) The organic EL element described in any one of 1) to 5) above, characterized in that the light-emitting layer contains a cyan light-emitting dopant.

[0046] 7) The organic EL element described in 6) above is characterized in that the cyan luminescent dopant is a pyrene derivative having a pyrene skeleton in the molecule.

[0047] 8) The organic EL element described in 6) above is characterized in that the cyan luminescent dopant is a compound represented by the following general formula (2) or general formula (3).

[0048] [Chemistry 3]

[0049]

[0050] [Chemistry 4]

[0051]

[0052] In general formulas (2) and (3), Q1 to Q3 may be the same or different from each other, representing substituted or unsubstituted aromatic hydrocarbons, substituted or unsubstituted fused polycyclic aromatic hydrocarbons, or substituted or unsubstituted aromatic heterocycles. X represents B, P, P=O, or P=S. Y1 to Y3 may be the same or different from each other, and are selected from any one of N-R4, CR5R6, O, S, Se, or SiR7R8. R4 to R8 may be the same or different from each other, representing hydrogen atoms, deuterium atoms, fluorine atoms, chlorine atoms, cyano, nitro, straight-chain or branched alkyl groups with 1 to 6 carbon atoms that may have substituents, cycloalkyl groups with 5 to 10 carbon atoms that may have substituents, or straight-chain alkyl groups with 2 to 6 carbon atoms that may have substituents. The groups can be branched alkenyl groups, linear or branched alkoxy groups with 1 to 6 carbon atoms that may have substituents, cycloalkoxy groups with 5 to 10 carbon atoms that may have substituents, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted fused polycyclic aromatic groups, or substituted or unsubstituted aryloxy groups. Furthermore, R5 and R6, and R7 and R8 can form rings by bonding between the respective groups via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms. However, when Y1 to Y3 are N-R4, CR5R6, or SiR7R8, R4 to R8 can form rings by bonding with their respective adjacent Q1, Q2, or Q3 via substituted or unsubstituted methylene groups, oxygen atoms, sulfur atoms, monosubstituted amino groups, etc.

[0053] 9) The organic EL element described in any one of 1) to 8) above, characterized in that the light-emitting layer contains an anthracene derivative having an anthracene skeleton in the molecule.

[0054] 10) The organic EL element described in 9) above, characterized in that the light-emitting layer contains a host material, which is an anthracene derivative having an anthracene skeleton in the molecule.

[0055] The terms R1 to R3 in general formula (1) represent "linear or branched alkyl groups having 1 to 6 carbon atoms that may have substituents", "cycloalkyl groups having 5 to 10 carbon atoms that may have substituents", or "linear or branched alkenyl groups having 2 to 6 carbon atoms that may have substituents". Specifically, examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, vinyl, allyl, isopropenyl, 2-butenyl, etc.

[0056] The "substituents" in general formula (1), represented by R1 to R3 as "linear or branched alkyl groups having 1 to 6 carbon atoms with substituents", "cycloalkyl groups having 5 to 10 carbon atoms with substituents", or "linear or branched alkenyl groups having 2 to 6 carbon atoms with substituents", specifically include deuterium atoms, cyano, nitro; halogen atoms such as fluorine, chlorine, bromine, and iodine; linear or branched alkoxy groups having 1 to 6 carbon atoms such as methoxy, ethoxy, and propoxy; alkenyl groups such as vinyl and allyl; aryloxy groups such as phenoxy and tolyoxy; arylalkoxy groups such as benzyloxy and phenethoxy; phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluorenyl, indene, pyrene, perylene, fluoranyl, and benzo[9,10] Aromatic hydrocarbon groups such as phenanthrene or fused polycyclic aromatic groups; aromatic heterocyclic groups such as pyridyl, pyrimidinyl, triazine, thiophene, furanyl, pyrrole, quinolinyl, isoquinolinyl, benzofuranyl, benzothiophene, indolyl, carbazoyl, benzoxazolyl, benzothiazoyl, quinoxalinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiophene, carbazoyl; disubstituted amino groups such as diphenylamino and dinaphthylamino, which are substituted with aromatic hydrocarbon groups or fused polycyclic aromatic groups; disubstituted amino groups such as dipyridylamino and dithiopheneamino, which are substituted with aromatic heterocyclic groups; and disubstituted amino groups substituted with substituents selected from aromatic hydrocarbon groups, fused polycyclic aromatic groups, or aromatic heterocyclic groups, which may be further substituted with the substituents exemplified above.

[0057] The terms R1 to R3 in general formula (1) represent "a straight-chain or branched alkoxy group having 1 to 6 carbon atoms that may have substituents" or "a cycloalkoxy group having 5 to 10 carbon atoms that may have substituents". Specifically, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy, n-pentoxy, n-hexoxy, cyclopentoxy, cyclohexoxy, cycloheptoxy, cyclooctoxy, 1-adamantoxy, 2-adamantoxy, etc.

[0058] In addition, these groups may have substituents, and as substituents, the same groups as those represented by "substituents" in the above general formula (1) R1 to R3, which are "linear or branched alkyl groups having 1 to 6 carbon atoms with substituents", "cycloalkyl groups having 5 to 10 carbon atoms with substituents" or "linear or branched alkenyl groups having 2 to 6 carbon atoms with substituents".

[0059] The "aromatic hydrocarbon group", "aromatic heterocyclic group" or "fused polycyclic aromatic group" represented by R1 to R3 in general formula (1) can specifically include phenyl, biphenyl, terphenyl, naphthyl, anthraceneyl, phenanthryl, fluorenyl, indene, and pyrene. The compounds include benzo[9,10]phenanthryl, perylyl, fluoranthyl, benzo[9,10]phenanthryl, pyridyl, pyrimidinyl, triazinyl, furanyl, pyrroliyl, thiopheneyl, quinolinyl, isoquinolinyl, benzofuranyl, benzothiopheneyl, indolyl, carbazolyl, benzooxazolyl, benzothiazolyl, quinoxalinyl, benzoimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiopheneyl, naphridinyl, phenanthrolyl, acridineyl, and carbazolyl, etc.

[0060] In addition, these groups may have substituents. Specifically, examples of substituents include deuterium atoms, cyano, nitro; halogen atoms such as fluorine, chlorine, bromine, and iodine; straight-chain or branched alkyl groups with 1 to 6 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, and n-hexyl; straight-chain or branched alkoxy groups with 1 to 6 carbon atoms such as methoxy, ethoxy, and propoxy; alkenyl groups such as vinyl and allyl; aryloxy groups such as phenoxy and tolyoxy; arylalkoxy groups such as benzyloxy and phenethoxy; and aromatic hydrocarbon groups such as phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluorenyl, indene, pyrene, perylene, fluoranyl, and benzo[9,10]phenanthrene. Fused polycyclic aromatic groups; aromatic heterocyclic groups such as pyridyl, pyrimidinyl, triazine, thiophene, furanyl, pyrroleyl, quinolinyl, isoquinolinyl, benzofuranyl, benzothiophene, indolyl, carbazoyl, benzoxazolyl, benzothiazoyl, quinoxalinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiophene, carbazoyl, etc.; disubstituted amino groups such as diphenylamino, dinaphthylamino, etc., which are substituted with aromatic hydrocarbon groups or fused polycyclic aromatic groups; disubstituted amino groups such as dipyridylamino, dithiopheneamino, etc., which are substituted with aromatic heterocyclic groups; disubstituted amino groups substituted with substituents selected from aromatic hydrocarbon groups, fused polycyclic aromatic groups, or aromatic heterocyclic groups, which may be further substituted with the substituents exemplified above.

[0061] As for the "aryloxy group" represented by R1 to R3 in general formula (1), specifically, phenoxy, biphenyloxy, terphenyloxy, naphthoxy, anthraquinoneoxy, phenanthreneoxy, fluorenoxy, indoxy, pyreneoxy, peryloxy, etc. can be listed.

[0062] In addition, these groups may have substituents, and as substituents, the same groups that can be represented by substituents as R1 to R3 in the above general formula (1), which represent "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group" or "substituted or unsubstituted fused polycyclic aromatic group", can be listed.

[0063] In general formula (1), A1 represents "a divalent group of a substituted or unsubstituted aromatic hydrocarbon," "a divalent group of a substituted or unsubstituted aromatic heterocycle," or "a divalent group of a substituted or unsubstituted fused polycyclic aromatic hydrocarbon." The terms "substituted or unsubstituted aromatic hydrocarbon," "substituted or unsubstituted aromatic heterocycle," or "substituted or unsubstituted fused polycyclic aromatic hydrocarbon" in these contexts refer to "aromatic hydrocarbon," "aromatic heterocycle," or "fused polycyclic aromatic hydrocarbon." Specifically, it can be listed as benzene, biphenyl, terphenyl, tetraphenyl, styrene, naphthalene, anthracene, acenaphthene, fluorene, phenanthrene, indene, pyrene, benzo[9,10]phenanthrene, pyridine, pyrimidine, triazine, pyrrole, furan, thiophene, quinoline, isoquinoline, benzofuran, benzothiophene, indoline, carbazole, carboline, benzoxazole, benzothiazole, quinoxaline, benzimidazole, pyrazole, dibenzofuran, dibenzothiophene, naphthidine, phenanthrene, acridine, etc.

[0064] Furthermore, the "divalent group of aromatic hydrocarbon", "divalent group of aromatic heterocycle" or "divalent group of fused polycyclic aromatic hydrocarbon" represented by A1 in general formula (1) indicates a divalent group generated by removing two hydrogen atoms from the aforementioned "aromatic hydrocarbon", "aromatic heterocycle" or "fused polycyclic aromatic hydrocarbon". In addition, these divalent groups may have substituents, and the substituents can be the same groups as those represented by the substituents that can be present in the "aromatic hydrocarbon group", "aromatic heterocycle group" or "fused polycyclic aromatic hydrocarbon group" represented by R1 to R3 in general formula (1) above.

[0065] The "aromatic hydrocarbon group," "aromatic heterocyclic group," or "fused polycyclic aromatic group" in Ar1 to Ar3 of general formula (1) specifically includes phenyl, biphenyl, terphenyl, naphthyl, anthraceneyl, phenanthryl, fluorenyl, indene, etc. Pyrene, perylene, fluoranthryl, benzo[9,10]phenanthrene, pyridinyl, pyrimidinyl, triazinyl, furanyl, pyrrolithyl, thiopheneyl, quinolinyl, isoquinolinyl, benzofuranyl, benzothiopheneyl, indolyl, carbazolyl, benzooxazolyl, benzothiazolyl, quinoxalinyl, benzoimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiopheneyl, naphridinyl, phenanthrolyl, acridineyl, and carbazolyl, etc.

[0066] In addition, these groups may have substituents, and as substituents, the same groups that can be represented by substituents as R1 to R3 in the above general formula (1), which represent "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group" or "substituted or unsubstituted fused polycyclic aromatic group", can be listed.

[0067] In general formula (1) or general formula (1a), A1 is preferably a "divalent group of a substituted or unsubstituted aromatic hydrocarbon" or a "divalent group of a substituted or unsubstituted fused polycyclic aromatic hydrocarbon", more preferably a divalent group generated by removing two hydrogen atoms from benzene, biphenyl, or naphthalene, and particularly preferably a divalent group generated by removing two hydrogen atoms from benzene.

[0068] In general formula (1) or general formula (1a), Ar1 is preferably "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted fused polycyclic aromatic group", carbazolyl, indolyl, dibenzofuranyl, or dibenzothiophene, more preferably substituted or unsubstituted phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, anthracenel, fluorenyl, carbazolyl, indolyl, dibenzofuranyl, or dibenzothiophene, and particularly preferably substituted or unsubstituted phenyl.

[0069] In general formula (1) or general formula (1a), Ar2 is preferably "substituted or unsubstituted aromatic hydrocarbon group" or "substituted or unsubstituted fused polycyclic aromatic group", more preferably substituted or unsubstituted phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, anthracene, fluorenyl, and especially preferably substituted or unsubstituted phenyl.

[0070] In general formula (1) or general formula (1a), Ar3 is preferably "substituted or unsubstituted aromatic hydrocarbon group" or "substituted or unsubstituted fused polycyclic aromatic group", more preferably substituted or unsubstituted phenyl, biphenyl, terphenyl, naphthyl, fluorenyl, and especially preferably substituted or unsubstituted phenyl.

[0071] Furthermore, among the compounds represented by general formula (1), compounds represented by general formula (1a) are more preferred.

[0072] The "aromatic hydrocarbon", "fused polycyclic aromatic hydrocarbon" or "aromatic heterocycle" represented by Q1 to Q3 in general formulas (2) and (3) can specifically include benzene, naphthalene, anthracene, fluorene, phenanthrene, pyridine, pyrimidine, triazine, pyrrole, furan, thiophene, quinoline, isoquinoline, indene, benzofuran, benzothiophene, indole, indololin, carbazole, carboline, benzoxazole, benzothiazole, quinoxaline, benzimidazole, pyrazole, dibenzofuran, dibenzothiophene, naphthidine, phenanthrene, acridine, etc.

[0073] Furthermore, these may have substituents, and the substituents can be the same groups that can be represented by the substituents in "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group" or "substituted or unsubstituted fused polycyclic aromatic group" represented by R1 to R3 in the above general formula (1). In addition, these substituents may form rings by bonding with each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms or sulfur atoms.

[0074] In general formulas (2) and (3), X represents B, P, P=O, or P=S. B is defined as a boron atom, P is defined as a phosphorus atom, P=O is defined as a phosphorus atom bonded to an oxygen atom by a double bond, or P=S is defined as a phosphorus atom bonded to a sulfur atom by a double bond.

[0075] In general formulas (2) and (3), Y1 to Y3 may be the same or different from each other, and are selected from any one of N-R4, CR5R6, O, S, Se, or SiR7R8. N-R4 is defined as a nitrogen atom having R4 as a substituent, CR5R6 is defined as a carbon atom having R5 and R6 as substituents, O is defined as an oxygen atom, S is defined as a sulfur atom, Se is defined as a selenium atom, and SiR7R8 is defined as a silicon atom having R7 and R8 as substituents. It should be noted that the definitions of R4 to R8 will be explained in more detail in the following description.

[0076] When Y1 to Y3 in general formulas (2) and (3) are N-R4, CR5R6, or SiR7R8, the terms "linear or branched alkyl group with 1 to 6 carbon atoms that may have substituents", "cycloalkyl group with 5 to 10 carbon atoms that may have substituents", or "linear or branched alkenyl group with 2 to 6 carbon atoms that may have substituents" represented by R4 to R8, specifically, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, vinyl, allyl, isopropenyl, 2-butenyl, etc. can be listed.

[0077] In addition, they may have substituents, and as substituents, the same groups as those represented by "substituents" in the above general formula (1) R1 to R3, which are "linear or branched alkyl groups having 1 to 6 carbon atoms with substituents", "cycloalkyl groups having 5 to 10 carbon atoms with substituents" or "linear or branched alkenyl groups having 2 to 6 carbon atoms with substituents".

[0078] When Y1 to Y3 in general formulas (2) and (3) are N-R4, CR5R6, or SiR7R8, the terms "linear or branched alkoxy group with 1 to 6 carbon atoms that may have substituents" or "cycloalkoxy group with 5 to 10 carbon atoms that may have substituents" represented by R4 to R8, specifically, can include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy, n-pentoxy, n-hexoxy, cyclopentoxy, cyclohexoxy, cycloheptoxy, cyclooctoxy, 1-adamantoxy, 2-adamantoxy, etc.

[0079] In addition, these groups may have substituents, and as substituents, the same groups as those represented by "substituents" in the above general formula (1) R1 to R3, which are "linear or branched alkyl groups having 1 to 6 carbon atoms with substituents", "cycloalkyl groups having 5 to 10 carbon atoms with substituents" or "linear or branched alkenyl groups having 2 to 6 carbon atoms with substituents".

[0080] When Y1 to Y3 in general formulas (2) and (3) are N-R4, CR5R6, or SiR7R8, the "aromatic hydrocarbon group" and "fused polycyclic aromatic group" represented by R4 to R8 can specifically include phenyl, biphenyl, terphenyl, naphthyl, anthraceneyl, phenanthrene, etc.

[0081] In addition, these groups may have substituents, and as substituents, the same groups that can be represented by substituents as R1 to R3 in the above general formula (1), which represent "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group" or "substituted or unsubstituted fused polycyclic aromatic group", can be listed.

[0082] In the case where Y1 to Y3 in general formula (2) and general formula (3) are N-R4, CR5R6, or SiR7R8, the "aryloxy group" represented by R4 to R8 can specifically include phenoxy, biphenyloxy, terphenyloxy, naphthoxy, anthraceneoxy, phenanthroxy, fluorenoxy, indoxy, pyreneoxy, peryloxy, etc.

[0083] In addition, these groups may have substituents, and as substituents, the same groups that can be represented by substituents as R1 to R3 in the above general formula (1), which represent "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group" or "substituted or unsubstituted fused polycyclic aromatic group", can be listed.

[0084] In general formulas (2) and (3), the "aromatic hydrocarbon", "fused polycyclic aromatic hydrocarbon" or "aromatic heterocycle" in "substituted or unsubstituted aromatic hydrocarbon", "substituted or unsubstituted fused polycyclic aromatic hydrocarbon" or "substituted or unsubstituted aromatic heterocycle" as Q1 to Q3 are preferably benzene, naphthalene, phenanthrene, pyridine, pyrimidine, indene, benzofuran, benzothiophene, or indole, and more preferably benzene or naphthalene.

[0085] In general formulas (2) and (3), when Y1 to Y3 are N-R4, CR5R6, or SiR7R8, R4 to R8 are preferably straight-chain or branched alkyl groups having 1 to 6 carbon atoms that may have substituents, cycloalkyl groups having 5 to 10 carbon atoms that may have substituents, straight-chain or branched alkenyl groups having 2 to 6 carbon atoms that may have substituents, straight-chain or branched alkoxy groups having 1 to 6 carbon atoms that may have substituents, or carbon atoms having substituents. The cycloalkoxy group having 5 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group, wherein R4 is more preferably a straight-chain or branched alkyl group having 1 to 6 carbon atoms that may have a substituent, a cycloalkyl group having 5 to 10 carbon atoms that may have a substituent, a straight-chain or branched alkenyl group having 2 to 6 carbon atoms that may have a substituent, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted fused polycyclic aromatic group.

[0086] In general formulas (2) and (3), Y1 is preferably N-R4, O, or S, and more preferably O or S. Furthermore, in general formulas (2) and (3), at least one of Y2 and Y3 is preferably N-R4, and more preferably both are N-R4. R4 is preferably "substituted or unsubstituted aromatic hydrocarbon group" or "substituted or unsubstituted fused polycyclic aromatic group", and more preferably substituted or unsubstituted phenyl, biphenyl, terphenyl, or naphthyl.

[0087] The effects of the invention

[0088] The arylamine compound represented by the above general formula (1) suitable for use in the organic EL element of the present invention can be used as a constituent material of the hole transport layer of the organic EL element. The arylamine compound represented by the above general formula (1) has the following characteristics: (1) good hole injection characteristics; (2) high hole mobility; (3) excellent electron blocking ability; (4) stable film state; (5) excellent heat resistance.

[0089] Regarding the organic EL element of the present invention, since an arylamine compound with a higher hole mobility than conventional hole transport materials, excellent electron blocking ability, excellent amorphous properties, and stable thin film state is used, a high-efficiency, low-drive-voltage, and long-life organic EL element can be realized.

[0090] Furthermore, in this invention, by making the hole transport layer a two-layer structure of a first hole transport layer and a second hole transport layer, and by forming the second hole transport layer on the light-emitting layer side using the arylamine compound represented by the above general formula (1), the electron blocking properties of the arylamine compound can be utilized to the maximum extent, and a long-life organic EL element can be realized with higher efficiency. Attached Figure Description

[0091] Figure 1 A diagram showing the structural formulas of compounds 1-1 to 1-15, which are arylamine compounds represented by general formula (1).

[0092] Figure 2 A diagram showing the structural formulas of compounds 1-16 to 1-20, which are arylamine compounds represented by general formula (1).

[0093] Figure 3 A diagram showing the structural formulas of compounds 1-21 to 1-31, which are arylamine compounds represented by general formula (1).

[0094] Figure 4 A diagram showing the structural formulas of compounds 1-32 to 1-42, which are arylamine compounds represented by general formula (1).

[0095] Figure 5 A diagram showing the structural formulas of compounds 1-43 to 1-55, which are arylamine compounds represented by general formula (1).

[0096] Figure 6 A diagram showing the structural formulas of compounds 1-56 to 1-64, which are arylamine compounds represented by general formula (1).

[0097] Figure 7A diagram showing the structural formulas of compounds 2-1 to 2-15, which are compounds represented by general formula (2).

[0098] Figure 8 A diagram showing the structural formulas of compounds 2-16 to 2-22, which are compounds represented by general formula (2).

[0099] Figure 9 A diagram showing the structural formulas of compounds 3-1 to 3-8, which are compounds represented by general formula (3).

[0100] Figure 10 The diagram illustrates the configuration of the organic EL elements in Examples 17-29 and Comparative Examples 1-3. Detailed Implementation

[0101] Specific examples of preferred compounds among the arylamine compounds represented by the above general formula (1) suitable for use in the organic EL element of the present invention are shown below. Figures 1-6 However, it is not limited to these compounds.

[0102] Specific examples of preferred compounds among those represented by the above general formula (2) or general formula (3) suitable for use in the organic EL element of the present invention are shown in the figures. Figures 7-8 or Figure 9 However, this invention is not limited to these compounds.

[0103] Regarding the purification of arylamine compounds represented by general formula (1), purification can be carried out by column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization using solvents, crystallization, sublimation purification, etc. For the identification of compounds, NMR analysis can be used. Glass transition temperature (Tg) and work function are measured as physical properties. Glass transition temperature (Tg) is an indicator of the stability of the thin film state, and work function is an indicator of hole transport and electron blocking properties. Furthermore, regarding the compounds used in the organic EL element of the present invention, a product purified by column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization using solvents, crystallization, etc., and finally purified by sublimation purification was used.

[0104] Regarding the glass transition temperature (Tg), for example, it can be determined using a high-sensitivity differential scanning calorimeter (manufactured by Blu-ray Aixes, DSC3100SA) for powder.

[0105] Regarding the work function, a 100nm thin film is fabricated on an ITO substrate, and the work function is determined using an ionization potential measuring device (manufactured by Sumitomo Heavy Industries, Ltd., PYS-202).

[0106] Examples of the organic EL element structure of the present invention include a structure that sequentially comprises an anode, a hole transport layer, a light-emitting layer, an electron transport layer, and a cathode on a substrate; a structure with a hole injection layer between the anode and the hole transport layer; a structure with a hole blocking layer between the light-emitting layer and the electron transport layer; and a structure with an electron injection layer between the electron transport layer and the cathode. In these multilayer structures, one or more organic layers may be omitted or may serve as multiple layers; for example, a structure that serves as both a hole injection layer and a hole transport layer, or a structure that serves as both an electron injection layer and an electron transport layer, etc., can also be fabricated. Furthermore, structures that stack two or more organic layers having the same function, structures that stack two hole transport layers, structures that stack two light-emitting layers, structures that stack two electron transport layers, etc., can also be fabricated.

[0107] As the structure of the organic EL element of the present invention, it is preferred that the hole transport layer is a two-layer structure consisting of a first hole transport layer and a second hole transport layer. In this case, the second hole transport layer is preferably adjacent to the light-emitting layer, and can function as an electron blocking layer.

[0108] As the anode of the organic EL element of the present invention, electrode materials with high work functions such as ITO and gold are used. As the hole injection layer of the organic EL element of the present invention, starburst-type triphenylamine derivatives; various triphenylamine tetramers and other triphenylamine derivatives; porphyrin compounds represented by copper phthalocyanine; acceptor heterocyclic compounds such as hexacyanoazabenzo[9,10]phenanthrene; and coating-type polymer materials can be used. In addition to vapor deposition, these materials can also be used to form thin films by known methods such as spin coating and inkjet printing.

[0109] As the hole transport layer of the organic EL element of the present invention, an arylamine compound represented by the above general formula (1) is used. As a hole transport material that can be mixed or used simultaneously with the arylamine compound represented by the above general formula (1), various organic amine compounds such as N,N'-diphenyl-N,N'-di(m-tolyl)benzidine (TPD), N,N'-diphenyl-N,N'-di(α-naphthyl)benzidine (NPD), N,N,N',N'-tetraphenylbenzidine and other benzidine derivatives, 1,1-bis[4-(di-4-tolylamino)phenyl]cyclohexane (TAPC), and arylamine compounds having a structure in which four triphenylamine structures are linked by single bonds or divalent groups without heteroatoms in the molecule, or arylamine compounds having a structure in which two triphenylamine structures are linked by single bonds or divalent groups without heteroatoms in the molecule, can be used. These materials can be used as individual films, as monolayers mixed with other materials, or as laminates of individual films, mixed films, or layers of mixed films. In addition to vapor deposition, these materials can also be used to form films using known methods such as spin coating and inkjet printing.

[0110] In addition, in the hole injection layer or hole transport layer, products obtained by further P-doping of materials commonly used in this layer, such as tri(bromophenyl)amine antimony hexachloride and axial alkene derivatives (e.g., see Patent Document 6), or polymeric compounds having structures of benzidine derivatives such as TPD in part of their structure can be used.

[0111] In the case where the hole transport layer of the organic EL element of the present invention has a two-layer structure of a first hole transport layer and a second hole transport layer, an arylamine compound represented by the above general formula (1) is used as the second hole transport layer located on the light-emitting layer side. As hole transport materials that can be mixed or used simultaneously with the arylamine compound represented by the above general formula (1), examples include carbazole derivatives such as 4,4',4”-tris(N-carbazolyl)triphenylamine (TCTA), 9,9-bis[4-(carbazo-9-yl)phenyl]fluorene, 1,3-bis(carbazo-9-yl)benzene (mCP), and 2,2-bis(4-carbazo-9-ylphenyl)adamantane (Ad-Cz), and compounds with electron blocking effects such as compounds having triphenylsilyl and triarylamine structures, represented by 9-[4-(carbazo-9-yl)phenyl]-9-[4-(triphenylsilyl)phenyl]-9H-fluorene.

[0112] These materials can be used as individual films, as monolayers mixed with other materials, or as laminates of individual films, mixed films, or layers of mixed films. In addition to vapor deposition, these materials can also be used to form films using known methods such as spin coating and inkjet printing.

[0113] As the light-emitting layer of the organic EL element of the present invention, compounds represented by the above general formula (2) or general formula (3) are preferably used. Furthermore, in addition to metal complexes of quinoline phenol derivatives, primarily Alq3, various metal complexes, anthracene derivatives, bis(styrene)benzene derivatives, pyrene derivatives, oxazole derivatives, poly(p-phenylene)ethylene derivatives, etc., can be used. Additionally, the light-emitting layer can be composed of a host material and a dopant material; in this case, anthracene derivatives having an anthracene skeleton in the molecule are preferably used as the host material. In addition, as dopant materials, pyrene derivatives having a pyrene skeleton in the molecule, compounds represented by the above general formula (2) or general formula (3) are preferred. Furthermore, heterocyclic compounds having a partial structure with an indole ring as a fused ring, heterocyclic compounds having a partial structure with a carbazole ring as a fused ring, carbazole derivatives, thiazole derivatives, benzimidazole derivatives, polydialkylfluorene derivatives, quinacridones, coumarin, rubrene, perylene, and their derivatives, benzopyran derivatives, indophenanthrene derivatives, rhodamine derivatives, aminostyryl derivatives, etc., can be used. These materials can be formed into films individually, or used as monolayers mixed with other materials to form films, or can be formed into stacked structures of layers formed individually, layers mixed to form films, or layers formed individually and layers mixed to form films.

[0114] In addition, phosphorescent materials can also be used as luminescent materials. Phosphorescent materials composed of metal complexes such as iridium and platinum can be used. Examples include green phosphorescent materials such as Ir(ppy)3, cyan phosphorescent materials such as Firpic and Fir6, and red phosphorescent materials such as Btp2Ir(acac). For this purpose, anthracene derivatives having an anthracene skeleton in the molecule are preferred as the host material. Furthermore, as host materials for hole injection and transport, carbazole derivatives such as 4,4'-bis(N-carbazolyl)biphenyl (CBP), TCTA, and mCP can be used. As host materials for electron transport, p-bis(triphenylsilyl)benzene (UGH2) and 2,2',2”-(1,3,5-phenylene)-tris(1-phenyl-1H-benzimidazole) (TPBI) can be used, enabling the fabrication of high-performance organic EL devices.

[0115] Regarding the doping of phosphorescent luminescent materials in the host material, in order to avoid concentration extinction, it is preferable to dope by co-evaporation at a rate of 1 to 30% by weight relative to the overall luminescent layer.

[0116] Alternatively, materials that emit delayed fluorescence, such as PIC-TRZ, CC2TA, PXZ-TRZ, 4CzIPN, and other CDCB derivatives, can also be used as luminescent materials (see, for example, Non-Patent Literature 3).

[0117] In addition to vapor deposition, these materials can also be used to form thin films using known methods such as spin coating and inkjet printing.

[0118] As the hole-blocking layer for the organic EL element of the present invention, in addition to metal complexes of phenanthroline derivatives such as copper bath (BCP) and quinolinephenol derivatives such as bis(2-methyl-8-hydroxyquinoline)-4-phenylphenol aluminum(III) (BAlq), various rare earth complexes, triazole derivatives, triazine derivatives, oxadiazole derivatives, and other compounds with hole-blocking properties can also be used. These materials can also serve as electron transport layer materials. These materials can be formed into films individually, or used as monolayers mixed with other materials to form films, or they can be fabricated into stacked structures of individually formed layers, mixed layers, or individually formed layers and mixed layers. In addition to vapor deposition, these materials can also be formed into thin films using known methods such as spin coating and inkjet printing.

[0119] As the electron transport layer of the organic EL element of the present invention, metal complexes of quinoline phenol derivatives, primarily Alq3 and BAlq, various metal complexes, triazole derivatives, triazine derivatives, oxadiazole derivatives, pyridine derivatives, pyrimidine derivatives, benzimidazole derivatives, thiadiazole derivatives, anthracene derivatives, carbodiimide derivatives, quinoxaline derivatives, pyridinodole derivatives, phenanthroline derivatives, thiophene derivatives, etc., can be used. These materials can be used individually as films, or mixed with other materials to form monolayer films, or layered structures of individually formed layers, mixed layers, or individually formed layers and mixed layers. In addition to vapor deposition, these materials can also be used to form thin films using known methods such as spin coating and inkjet printing.

[0120] As the electron injection layer of the organic EL element of the present invention, alkali metal salts such as lithium fluoride and cesium fluoride, alkaline earth metal salts such as magnesium fluoride, metal complexes of quinoline phenol derivatives such as lithium quinoline phenol, metal oxides such as aluminum oxide, or metals such as ytterbium (Yb), samarium (Sm), calcium (Ca), strontium (Sr), and cesium (Cs) can be used. However, in the preferred selection of the electron transport layer and the cathode, these can be omitted.

[0121] Furthermore, in the electron injection layer or electron transport layer, it is possible to use products that have been further N-doped with metals such as cesium, compared to the materials typically used in that layer.

[0122] As the cathode of the organic EL element of the present invention, an electrode material with a low work function, such as aluminum, or an alloy with an even lower work function, such as a magnesium-silver alloy, a magnesium-indium alloy, or an aluminum-magnesium alloy, is used.

[0123] The embodiments of the present invention will be specifically described below through examples, but the present invention is not limited to the following examples.

[0124] Example 1

[0125] Synthesis of (4-naphth-2-yl-phenyl)-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine (1-2)

[0126] In a reaction vessel, 15.0 g of (4-naphth-2-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine, 12.3 g of 9-(4-bromo-phenyl)-phenanthrene, 4.8 g of sodium tert-butoxy, and 240 mL of toluene were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen gas was introduced. Then, 0.1 g of palladium(II) acetate and 0.3 g of tris(tert-butyl)phosphine were added, and the mixture was refluxed and stirred for 4 hours. After natural cooling, the filtrate was concentrated under reduced pressure to obtain a crude product. The crude product was purified by recrystallization using toluene to obtain 18.7 g of a white powder of (4-naphth-2-yl-phenyl)-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine (1-2) (yield 80%).

[0127] [Chemistry 5]

[0128]

[0129] The structure of the obtained white powder was identified using NMR.

[0130] use 1 H-NMR (CDCl3) detected the following 37 hydrogen signals.

[0131] δ(ppm)=8.81(1H), 8.76(1H), 8.11(1H), 8.09(1H), 7.92(4H), 7.80(1H), 7. 77(2H), 7.75-7.58(5H), 7.57-7.48(4H), 7.48-7.30(7H), 7.27-7.14(10H).

[0132] Example 2

[0133] Synthesis of (4-naphth-1-yl-phenyl)-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine (1-3)

[0134] In a reaction vessel, 15.0 g of (4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine, 9.4 g of 1-(4-bromo-phenyl)-naphthalene, 4.3 g of sodium tert-butoxy, and 210 mL of toluene were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen was introduced. Then, 0.1 g of palladium(II) acetate and 0.1 g of tris(tert-butyl)phosphine were added, and the mixture was refluxed and stirred overnight. After natural cooling, the filtrate was concentrated under reduced pressure to obtain a crude product. The crude product was purified by column chromatography (support: silica gel, eluent: dichloromethane / n-heptane) to obtain 15.9 g of a white powder of (4-naphthyl-1-yl-phenyl)-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine (1-3) (yield 76%).

[0135] [Chemistry 6]

[0136]

[0137] The structure of the obtained white powder was identified using NMR.

[0138] use 1 H-NMR (CDCl3) detected the following 37 hydrogen signals.

[0139] δ(ppm)=8.83(1H), 8.77(1H), 8.12(2H), 7.95(2H), 7.89(1H), 7.80(1H), 7.77-7.60(5H), 7.60-7.41(14H), 7.38(1H), 7.28-7.17(9H).

[0140] Example 3

[0141] <Synthesis of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”;4”,1”']tetraphenyl-4'-yl-amine (1-4)>

[0142] In a reaction vessel, 10.0 g of biphenyl-4-yl-(6-bromo-[1,1';4',1”]terphenyl-3-yl)-(4-phenanthrene-9-yl-phenyl)-amine, 2.5 g of phenylboronic acid, 3.6 g of potassium carbonate, 80 mL of toluene, 30 mL of ethanol, and 30 mL of H2O were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen gas was introduced. Then, 0.3 g of tetra(triphenylphosphine)palladium(0) was added, and the mixture was refluxed and stirred overnight. After natural cooling, the organic layer was separated and extracted by liquid-liquid extraction, and concentrated under reduced pressure to obtain the crude product. The crude product was purified by crystallization using a dichloromethane / acetone mixed solvent to obtain 5.4 g of a white powder of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”;4”,1”']tetraphenyl-4'-yl-amine (1-4) (yield 54%).

[0143] [Chemistry 7]

[0144]

[0145] The structure of the obtained white powder was identified using NMR.

[0146] use 1 H-NMR (CDCl3) detected the following 39 hydrogen signals.

[0147] δ(ppm)=8.82(1H), 8.76(1H), 8.11(1H), 7.94(1H), 7.78(1H), 7.75-7.56(10H), 7.56-7.37(15H), 7.37-7.30(3H), 7.27-7.20(6H).

[0148] Example 4

[0149] <Synthesis of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-(4”-naphth-1-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-5)>

[0150] In a reaction vessel, 10.0 g of biphenyl-4-yl-(6-bromo-4'-naphth-1-yl-biphenyl-3-yl)-(4-phenanthrene-9-yl-phenyl)-amine, 2.3 g of phenylboronic acid, 3.4 g of potassium carbonate, 80 mL of toluene, 30 mL of ethanol, and 30 mL of H2O were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen gas was introduced. Then, 0.3 g of tetra(triphenylphosphine)palladium(O) was added, and the mixture was refluxed and stirred overnight. After natural cooling, the organic layer was separated and extracted using a liquid-liquid extraction method, and concentrated under reduced pressure to obtain the crude product. The crude product was purified by column chromatography (support: silica gel, dissolution solution: dichloromethane / n-heptane) to obtain a white powder of biphenyl-4-yl-(4-phenanthroline-9-yl-phenyl)-(4”-naphth-1-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-5): 2.8 g (yield 28%).

[0151] [Chemistry 8]

[0152]

[0153] The structure of the obtained white powder was identified using NMR.

[0154] use 1 H-NMR (CDCl3) detected the following 41 hydrogen signals.

[0155] δ(ppm)=8.82(1H), 8.76(1H), 8.13(1H), 7.91(4H), 7.79(1H), 7.76-7.58(8H), 7.58-7.39(14H), 7.39-7.25(11H).

[0156] Example 5

[0157] <Synthesis of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-(4”-naphth-2-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-6)>

[0158] In a reaction vessel, 10.0 g of biphenyl-4-yl-(6-bromo-4'-naphth-2-yl-biphenyl-3-yl)-(4-phenanthrene-9-yl-phenyl)-amine, 2.3 g of phenylboronic acid, 3.4 g of potassium carbonate, 80 mL of toluene, 30 mL of ethanol, and 30 mL of H2O were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen gas was introduced. Then, 0.3 g of tetra(triphenylphosphine)palladium(O) was added, and the mixture was refluxed and stirred overnight. After natural cooling, the organic layer was separated and extracted using a liquid-liquid extraction method, and concentrated under reduced pressure to obtain the crude product. The crude product was purified by crystallization using a dichloromethane / acetone mixed solvent to obtain a white powder of biphenyl-4-yl-(4-phenanthroline-9-yl-phenyl)-(4”-naphth-2-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-6): 5.8 g (yield 58%).

[0159] [Chemistry 9]

[0160]

[0161] The structure of the obtained white powder was identified using NMR.

[0162] use 1 H-NMR (CDCl3) detected the following 41 hydrogen signals.

[0163] δ(ppm)=8.83(1H), 8.77(1H), 8.14(1H), 8.05(1H), 7.91(4H), 7.79(1H), 7.78-7.59(11H), 7.59-7.34(12H), 7.34-7.22(9H).

[0164] Example 6

[0165] <Synthesis of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,2'; 1',1”; 4”,1”']tetraphenyl-4'-yl-amine (1-7)>

[0166] In a reaction vessel, 14.5 g of biphenyl-4-yl-[1,2';1',1”;4”,1”']-tetraphenyl-4'-yl-amine, 9.3 g of 9-(4-bromo-phenyl)-phenanthrene, 3.2 g of sodium tert-butoxy, and 93 mL of toluene were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen was introduced. Then, 0.1 g of palladium(II) acetate and 0.2 g of tris(tert-butyl)phosphine were added, and the mixture was refluxed and stirred for 3 hours. After natural cooling, H2O was added, and the precipitated solid was filtered to obtain a crude product. The crude product was purified by crystallization using a chlorobenzene / acetone mixed solvent to obtain 14.0 g of a white powder of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,2';1',1”;4”,1”']tetraphenyl-4'-yl-amine (1-7) (yield 69%).

[0167] [Chemistry 10]

[0168]

[0169] The structure of the obtained white powder was identified using NMR.

[0170] use 1 H-NMR (CDCl3) detected the following 39 hydrogen signals.

[0171] δ(ppm)=8.84(1H), 8.77(1H), 8.14(1H), 7.90(1H), 7.80(1H), 7.78-7.60(10H), 7.60-7.33(17H), 7.33-7.20(7H).

[0172] Example 7

[0173] <Synthesis of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';4',1”;2”,1”':4”',1””]pentaphenyl-4”-yl-amine (1-12)>

[0174] Instead of phenylboronic acid in Example 3, 4-biphenylboronic acid was used, and the same operation was performed to obtain a white powder of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';4',1”;2”,1”':4”',1””]pentaphenyl-4”-yl-amine (1-12): 8.0 g (yield 73%).

[0175] [Chemistry 11]

[0176]

[0177] The structure of the obtained white powder was identified using NMR.

[0178] use 1H-NMR (CDCl3) detected the following 43 hydrogen signals.

[0179] δ(ppm)=8.76-8.84(2H), 8.12-8.14(1H), 7.94-7.96(1H), 7.79(1H), 7.60-7.75(12H), 7.42-7.56(18H), 7.28-7.39(8H).

[0180] Example 8

[0181] <Synthesis of phenyl-(4-phenanthrene-9-yl-phenyl)-(4-naphth-1-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-23)>

[0182] In a reaction vessel, 13.3 g of (4-phenanthrene-9-ylphenyl)-(4-naphth-1-yl-[1,1';2',1”]terphenyl-4'-yl)-amine, 3.7 g of bromobenzene, 3.1 g of sodium tert-butoxy, and 130 mL of toluene were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen gas was introduced. Then, 0.1 g of palladium(II) acetate and 0.2 g of tris(tert-butyl)phosphine were added, and the mixture was refluxed and stirred for 22 hours. After natural cooling, the filtrate was concentrated under reduced pressure to obtain a crude product. The crude product was purified by recrystallization using toluene and acetone to obtain 11.5 g of a white powder of phenyl-(4-phenanthrene-9-ylphenyl)-(4-naphth-1-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-23) (yield 77%).

[0183] [Chemistry 12]

[0184]

[0185] The structure of the obtained white powder was identified using NMR.

[0186] use 1 H-NMR (CDCl3) detected the following 37 hydrogen signals.

[0187] δ(ppm)=8.75-8.84(2H), 8.12-8.18(1H), 7.86-7.98(4H), 7.12-7.73(30H).

[0188] Example 9

[0189] <Synthesis of phenyl-(4-phenanthrene-9-yl-phenyl)-(4-naphth-2-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-24)>

[0190] Instead of (4-phenanthrene-9-yl-phenyl)-(4-naphth-1-yl-[1,1';2',1”]terphenyl-4'-yl)-amine in Example 8, the same operation was performed to obtain a white powder of phenyl-(4-phenanthrene-9-yl-phenyl)-(4-naphth-2-yl-[1,1';2',1”]terphenyl-4'-yl)-amine (1-24): 9.3 g (yield 73%).

[0191] [Chemistry 13]

[0192]

[0193] The structure of the obtained white powder was identified using NMR.

[0194] use 1 H-NMR (CDCl3) detected the following 37 hydrogen signals.

[0195] δ(ppm)=8.75-8.83(2H), 8.08-8.12(2H), 7.88-7.95(4H), 7.62-7.79(8H), 7.23-7.54(20H), 7.14-7.16(1H).

[0196] Example 10

[0197] <Synthesis of Naphth-1-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”,4”,1”']tetraphenyl-5'-yl-amine (1-29)>

[0198] In a reaction vessel, 20.0 g of (4-phenanthrene-9-yl-phenyl)-[1,1';2',1”,4”,1”']tetraphenyl-5'-yl-amine, 8.0 g of 1-bromonaphthalene, 5.0 g of sodium tert-butoxy, and 200 mL of toluene were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen gas was introduced. Then, 0.4 g of palladium(II) acetate and 0.7 g of tris(tert-butyl)phosphine were added, and the mixture was refluxed and stirred for 2 hours. After natural cooling, the filtrate was concentrated under reduced pressure to obtain a crude product. The crude product was purified by recrystallization using toluene and acetone to obtain 4.4 g of a white powder of naphth-1-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”,4”,1”']tetraphenyl-5'-yl-amine (1-29) (yield 18%).

[0199] [Chemistry 14]

[0200]

[0201] The structure of the obtained white powder was identified using NMR.

[0202] use 1 H-NMR (CDCl3) detected the following 37 hydrogen signals.

[0203] δ(ppm)=8.73-8.81(2H), 8.17-8.20(1H), 8.07-8.09(1H), 7.97-8.01(1H), 7.86-7.91(2H), 7.29-7.74(22H), 7.14-7.24(8H).

[0204] Example 11

[0205] <Synthesis of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';3',1”;2”,1”':4”',1””]pentaphenyl-4”-yl-amine (1-41)>

[0206] Instead of phenylboronic acid in Example 3, 3-biphenylboronic acid was used, and the same operation was performed to obtain a white powder of biphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';3',1”;2”,1”':4”',1””]pentaphenyl-4”-yl-amine (1-41): 5.6 g (yield 51%).

[0207] [Chemistry 15]

[0208]

[0209] The structure of the obtained white powder was identified using NMR.

[0210] use 1 H-NMR (CDCl3) detected the following 43 hydrogen signals.

[0211] δ(ppm)=8.75-8.84(2H), 8.12-8.14(1H), 7.94-7.96(1H), 7.79(1H), 7.60-7.75(10H), 7.27-7.56(28H).

[0212] Example 12

[0213] Synthesis of [1,1':3',1”]terphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine (1-60)>

[0214] In a reaction vessel, 9.2 g of (4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine, 5.2 g of 4-bromo-[1,1':3',1”]terphenyl, 1.9 g of sodium tert-butoxy, and 78 mL of toluene were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen was introduced. Then, 0.1 g of palladium(II) acetate and 0.1 g of tris(tert-butyl)phosphine were added, and the mixture was refluxed and stirred for 3 hours. After natural cooling, the filtrate was concentrated to obtain a crude product. The crude product was purified by column chromatography to obtain 7.1 g of a white powder of [1,1':3',1”]terphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”]terphenyl-4'-yl-amine (1-60) (yield 58%).

[0215] [Chemistry 16]

[0216]

[0217] The structure of the obtained white powder was identified using NMR.

[0218] use 1 H-NMR (CDCl3) detected the following 39 hydrogen signals.

[0219] δ(ppm)=8.75-8.84(2H), 8.11-8.13(1H), 7.93-7.95(1H), 7.87(1H), 7.78(1H), 7.48-7.72(15H), 7.17-7.43(18H).

[0220] Example 13

[0221] Synthesis of <[1,1':4',1”]terphenyl-4-yl-(4-phenanthrene-9-yl-phenyl)-[1,1';2',1”:3",1”']tetraphenyl-5'-yl-amine (1-61)>

[0222] In a reaction vessel, 8.9 g of (4-phenanthrene-9-ylphenyl)-[1,1';2',1”:3",1”']tetraphenyl-5'-yl-amine, 4.0 g of 4-bromo-[1,1':4',1”]terphenyl, 1.9 g of sodium tert-butoxy, and 40 mL of toluene were added. The mixture was irradiated with ultrasound for 30 minutes while nitrogen gas was introduced. Then, 0.1 g of palladium(II) acetate and 0.2 g of tris(tert-butyl)phosphine were added, and the mixture was refluxed and stirred for 5 hours. After natural cooling, the filtrate was concentrated to obtain a crude product. The crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain a white powder of [1,1':4',1”]terphenyl-4-yl-(4-phenanthrene-9-ylphenyl)-[1,1';2',1”:3",1”']tetraphenyl-5'-yl-amine (1-61).

[0223] 9.1g (yield 88%).

[0224] [Chemistry 17]

[0225]

[0226] The structure of the obtained white powder was identified using NMR.

[0227] use 1 H-NMR (CDCl3) detected the following 43 hydrogen signals.

[0228] δ(ppm)=8.76-8.84(2H), 8.11-8.13(1H), 7.94-7.96(1H), 7.79(1H), 7.61-7.75(12H), 7.22-7.56(26H).

[0229] Example 14

[0230] <Synthesis of Compound (2-11)>

[0231] In a reaction vessel, 45.0 g of 1-bromobenzene (D-substituted), 58.0 g of 4-tert-butylaniline, 1.0 g of palladium(II) acetate, 30.0 g of sodium tert-butoxy, 2.0 g of bis(diphenylphosphine)-1,1'-binaphthylene, and 450 mL of toluene were added and stirred under reflux for 24 hours. After natural cooling, the mixture was concentrated and purified by column chromatography to obtain 49.9 g (78% yield) of the following compound (2-11a) in powder form.

[0232] [Chemistry 18]

[0233]

[0234] The following compounds were added to a reaction vessel: 20.0 g of compound (2-11a), 18.4 g of compound (2-11b), 0.5 g of palladium(II) acetate, 18.9 g of sodium tert-butoxy, 0.8 g of tris(tert-butyl)phosphine, and 200 mL of toluene. The mixture was refluxed and stirred for 24 hours. After natural cooling, the mixture was concentrated and purified by column chromatography to obtain 21.5 g (84% yield) of powder of compound (2-11c).

[0235] [Chemistry 19]

[0236]

[0237] [Chemistry 20]

[0238]

[0239] The above compound (2-11c) 12.0 g and tert-butylbenzene 120 mL were added to a reaction vessel. Then, 42.5 mL of n-butyllithium was added dropwise at -78 °C, and the mixture was stirred at 60 °C for 3 hours while nitrogen gas was introduced. Next, 11.3 g of boron tribromide was added dropwise at -78 °C, and the mixture was stirred at room temperature for 1 hour. Then, 5.9 g of N,N-diisopropylethylamine was added dropwise at 0 °C, and the mixture was stirred at 120 °C for 2 hours. After natural cooling, an aqueous sodium acetate solution was added, stirred, and extracted with ethyl acetate. The organic layer was concentrated and purified by column chromatography to obtain 1.7 g (yield 11%) of the following compound (2-11).

[0240] [Chemistry 21]

[0241]

[0242] Example 15

[0243] For arylamine compounds represented by general formula (1), the glass transition temperature (Tg) was determined by a high-sensitivity differential scanning calorimeter (manufactured by Blu-ray Aixes, DSC3100SA).

[0244]

[0245] Arylamine compounds represented by general formula (1) have a glass transition temperature (Tg) of over 100 °C, indicating that the thin film is stable.

[0246] Example 16

[0247] Using an arylamine compound represented by general formula (1), a vapor-deposited film with a thickness of 100 nm was fabricated on an ITO substrate, and the work function was measured by an ionization potential measuring device (manufactured by Sumitomo Heavy Industries, Ltd., PYS-202).

[0248]

[0249] It can be seen that, for arylamine compounds represented by general formula (1), compared with the work function of 5.4 eV of general hole transport materials such as NPD and TPD, they exhibit suitable energy levels, good hole transport capability, and excellent electron blocking capability.

[0250] Example 17

[0251] Regarding organic EL devices, such as Figure 10 As shown, the product on which an ITO electrode is pre-formed as a transparent anode 2 on a glass substrate 1 is deposited by vapor deposition in the following order: hole injection layer 3, first hole transport layer 4, second hole transport layer 5, light-emitting layer 6, electron transport layer 7, electron injection layer 8, and cathode (aluminum electrode) 9.

[0252] Specifically, a glass substrate 1 with an ITO film of 150 nm thickness was ultrasonically cleaned in isopropanol for 20 minutes and then dried on a hot plate heated to 200°C for 10 minutes. After a 15-minute UV ozone treatment, the ITO-coated glass substrate was mounted in a vacuum evaporation machine, and the pressure was reduced to below 0.001 Pa. Next, as a hole injection layer 3 covering a transparent anode 2, binary evaporation was performed on an electron acceptor (acceptor-1) and a compound (HTM-1) of the following structural formula at a evaporation rate ratio of acceptor-1:compound (HTM-1) = 3:97, resulting in a film thickness of 10 nm. On this hole injection layer 3, as a first hole transport layer 4, a compound (HTM-1) of the following structural formula was formed to achieve a film thickness of 55 nm. On this first hole transport layer 4, as a second hole transport layer 5, compounds (1-2) of Example 1 were formed to achieve a film thickness of 5 nm. On the second hole transport layer 5, as the light-emitting layer 6, binary deposition was performed on compounds (2-11) of Example 14 and compound (EMH-1) with the following structural formula at a deposition rate ratio of compound (2-11): compound (EMH-1) = 5:95, forming a film thickness of 20 nm. On the light-emitting layer 6, as the electron transport layer 7, binary deposition was performed on compounds (ETM-1) and (ETM-2) with the following structural formula at a deposition rate ratio of compound (ETM-1): compound (ETM-2) = 50:50, forming a film thickness of 30 nm. On the electron transport layer 7, as the electron injection layer 8, lithium fluoride was formed to achieve a film thickness of 1 nm. Finally, 100 nm of aluminum was deposited to form the cathode 9. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of measuring the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0253] [Chemistry 22]

[0254]

[0255] [Chemistry 23]

[0256]

[0257] [Chemistry 24]

[0258]

[0259] [Chemistry 25]

[0260]

[0261] [Chemistry 26]

[0262]

[0263] [Chemistry 27]

[0264]

[0265] [Chemistry 28]

[0266]

[0267] Example 18

[0268] In Example 17, compound (1-3) of Example 2 was used instead of compound (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0269] [Chemistry 29]

[0270]

[0271] Example 19

[0272] In Example 17, compounds (1-4) of Example 3 were used instead of compounds (1-2) of Example 1 as the material for the second hole transport layer 5, and an organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of the measurement of the luminescence characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0273] [Chemistry 30]

[0274]

[0275] Example 20

[0276] In Example 17, compounds (1-5) of Example 4 were used instead of compounds (1-2) of Example 1 as the material for the second hole transport layer 5, and an organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of the measurement of the luminescence characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0277] [Chemistry 31]

[0278]

[0279] Example 21

[0280] In Example 17, compounds (1-6) of Example 5 were used instead of compounds (1-2) of Example 1 as the material for the second hole transport layer 5, and an organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of the measurement of the luminescence characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0281] [Chemistry 32]

[0282]

[0283] Example 22

[0284] In Example 17, compounds (1-7) of Example 6 were used instead of compounds (1-2) of Example 1 as the material for the second hole transport layer 5, and an organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of the measurement of the luminescence characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0285] [Chemistry 33]

[0286]

[0287] Example 23

[0288] In Example 17, compounds (1-12) of Example 7 were used instead of compounds (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0289] [Chemistry 34]

[0290]

[0291] Example 24

[0292] In Example 17, the compound (1-23) of Example 8 was used instead of the compound (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0293] [Chemistry 35]

[0294]

[0295] Example 25

[0296] In Example 17, compound (1-24) of Example 9 was used instead of compound (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0297] [Chemistry 36]

[0298]

[0299] Example 26

[0300] In Example 17, the compound (1-29) of Example 10 was used instead of the compound (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0301] [Chemistry 37]

[0302]

[0303] Example 27

[0304] In Example 17, the compound (1-41) of Example 11 was used instead of the compound (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0305] [Chemistry 38]

[0306]

[0307] Example 28

[0308] In Example 17, compound (1-60) of Example 12 was used instead of compound (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0309] [Chemistry 39]

[0310]

[0311] Example 29

[0312] In Example 17, the compound (1-61) of Example 13 was used instead of the compound (1-2) of Example 1 as the material for the second hole transport layer 5, and the organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the light emission characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0313] [Chemistry 40]

[0314]

[0315] [Comparative Example 1]

[0316] For comparison, in Example 17, the material for the second hole transport layer 5 was replaced by compound (HTM-2) with the following structural formula, and an organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of the measurement of the luminescence characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0317] [Chemistry 41]

[0318]

[0319] [Comparative Example 2]

[0320] For comparison, in Example 17, the material for the second hole transport layer 5 was replaced by compound (HTM-3) with the following structural formula, and an organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of the measurement of the luminescence characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0321] [Chemistry 42]

[0322]

[0323] [Comparative Example 3]

[0324] For comparison, in Example 17, the material for the second hole transport layer 5 was replaced by a compound with the following structural formula (HTM-4) instead of compounds (1-2) from Example 1, and an organic EL element was fabricated under the same conditions. The characteristics of the fabricated organic EL element were measured in air at room temperature. The results of the measurement of the luminescence characteristics of the fabricated organic EL element when a DC voltage was applied are summarized in Table 1.

[0325] [Chemistry 43]

[0326]

[0327] The results of measuring the lifetime of the organic EL devices prepared in Examples 17-29 and Comparative Examples 1-3 are summarized in Table 1. Regarding the lifetime, the initial luminous intensity (initial luminance) at the start of luminescence was set to 2000 cd / m². 2 When driven by a constant current, the luminous intensity decays until it reaches 1900 cd / m². 2 The measurement was taken at a time when the initial brightness was set to 100% and the decay was 95% (equivalent to 95% attenuation).

[0328] [Table 1]

[0329]

[0330] As shown in Table 1, the current density is 10 mA / cm². 2 Regarding the luminous efficiency under flowing current, the organic EL elements of Comparative Examples 1-3 have an efficiency of 7.42-9.34 cd / A, while those of Examples 17-29 have an efficiency of 10.04-11.18 cd / A, indicating higher efficiency. Furthermore, in terms of power efficiency, the organic EL elements of Comparative Examples 1-3 have an efficiency of 6.26-7.91 lm / W, while those of Examples 17-29 have an efficiency of 8.65-9.82 lm / W, also indicating higher efficiency. Moreover, in terms of device lifetime (95% decay), the organic EL elements of Comparative Examples 1-3 have a lifetime of 206-235 hours, while those of Examples 17-29 have a lifetime of 285-356 hours, indicating a longer lifetime.

[0331] As can be seen from the above results, the arylamine compound represented by general formula (1) with a specific structure has a higher hole mobility and excellent electron blocking ability compared with the conventional arylamine compounds used in Comparative Examples 1 to 3. Therefore, for the organic EL element of the embodiment using the material of the present invention, compared with the organic EL element of the comparative example using the conventional material, it is possible to achieve an organic EL element with high luminous efficiency and long lifetime.

[0332] Industrial availability

[0333] The organic EL element of the present invention, which uses an arylamine compound with a specific structure, has improved luminous efficiency and can improve the durability of the organic EL element, for example, it can be developed for use in household electrical appliances and lighting.

[0334] 1. Glass substrate

[0335] 2. Transparent anode

[0336] 3. Hole injection layer

[0337] 4 First Hole Transport Layer

[0338] 5. Second Hole Transport Layer

[0339] 6. Light-emitting layer

[0340] 7. Electron Transport Layer

[0341] 8 Electron Injection Layer

[0342] 9 Cathode

Claims

1. An organic electroluminescent element, comprising at least an anode, a hole transport layer, a light-emitting layer, an electron transport layer, and a cathode in sequence, characterized in that, The hole transport layer contains an arylamine compound represented by the following general formula (1). In the formula, R1 and R2 represent deuterium atoms, fluorine atoms, chlorine atoms, cyano groups, nitro groups, linear or branched alkyl groups with 1 to 6 carbon atoms that may have substituents, cycloalkyl groups with 5 to 10 carbon atoms that may have substituents, linear or branched alkenyl groups with 2 to 6 carbon atoms that may have substituents, linear or branched alkoxy groups with 1 to 6 carbon atoms that may have substituents, cycloalkoxy groups with 5 to 10 carbon atoms that may have substituents, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic heterocyclic groups, substituted or unsubstituted fused polycyclic aromatic groups, or substituted or unsubstituted aryloxy groups; R3 represents hydrogen atoms, deuterium atoms, fluorine atoms, chlorine atoms, cyano groups, nitro groups, linear or branched alkyl groups with 1 to 6 carbon atoms that may have substituents, cycloalkyl ... hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted aromatic hydrocarbon groups, The following are considered as substituents: a straight-chain or branched alkyl group having 1 to 6 carbon atoms; a cycloalkyl group having 5 to 10 carbon atoms; a straight-chain or branched alkenyl group having 2 to 6 carbon atoms; a straight-chain or branched alkoxy group having 1 to 6 carbon atoms; a cycloalkoxy group having 5 to 10 carbon atoms; a substituted or unsubstituted aromatic hydrocarbon group; a substituted or unsubstituted aromatic heterocyclic group; a substituted or unsubstituted fused polycyclic aromatic group; or a substituted or unsubstituted aryloxy group. A1 represents a divalent group of a substituted or unsubstituted aromatic hydrocarbon, a divalent group of a substituted or unsubstituted aromatic heterocycle, or a divalent group of a substituted or unsubstituted fused polycyclic aromatic hydrocarbon. Ar1~Ar2 represent substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthrayl, substituted or unsubstituted fluorenyl, substituted or unsubstituted indole, substituted or unsubstituted pyrene, substituted or unsubstituted peryl, substituted or unsubstituted fluoranyl, substituted or unsubstituted benzo[9,10]phenanthyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted triazine, substituted or unsubstituted furanyl, substituted or unsubstituted pyrroleyl, substituted or unsubstituted thiopheneyl, substituted or unsubstituted The following are substituted quinolinyl, substituted or unsubstituted isoquinolinyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted benzothiophenyl, substituted or unsubstituted indolyl, substituted or unsubstituted carbazoyl, substituted or unsubstituted benzooxazolyl, substituted or unsubstituted benzothiazoyl, substituted or unsubstituted quinoxalinyl, substituted or unsubstituted benzimidazolyl, substituted or unsubstituted pyrazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted naphthidyl, substituted or unsubstituted phenanthrolinel, substituted or unsubstituted acridinel, or substituted or unsubstituted carolinyl. When Ar1 to Ar2 have substituents, the substituents are deuterium atoms, cyano, nitro, halogen atoms, straight-chain or branched alkyl groups with 1 to 6 carbon atoms, straight-chain or branched alkoxy groups with 1 to 6 carbon atoms, alkenyl, aryloxy, arylalkoxy, phenyl, biphenyl, terphenyl, naphthyl, anthracene, fluorenyl, indene, pyrenyl, perylene, fluoranyl, benzo[9,10]phenanthryl, pyridyl, pyrimidinyl, triazine, thiophene, furanyl, pyrroleyl. Quinolinyl, isoquinolinyl, benzofuranyl, benzothiophenyl, indolyl, carbazoyl, benzoxazolyl, benzothiazoyl, quinoxolinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiaphenyl, carbazoyl, disubstituted amino group substituted with an aromatic hydrocarbon group or a fused polycyclic aromatic group, disubstituted amino group substituted with an aromatic heterocyclic group, or disubstituted amino group substituted with a substituent selected from aromatic hydrocarbon groups, fused polycyclic aromatic groups or aromatic heterocyclic groups. Ar3 represents substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthrayl, substituted or unsubstituted indole, substituted or unsubstituted pyrene, substituted or unsubstituted peryl, substituted or unsubstituted fluoranthyl, substituted or unsubstituted benzo[9,10]phenanthyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted triazine, substituted or unsubstituted furanyl, substituted or unsubstituted pyrroleyl, substituted or unsubstituted thiopheneyl, substituted or unsubstituted quinolinyl, etc. Substituted or unsubstituted isoquinolinyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted benzothiophenyl, substituted or unsubstituted indolyl, substituted or unsubstituted carbazoyl, substituted or unsubstituted benzooxazolyl, substituted or unsubstituted benzothiazoyl, substituted or unsubstituted quinoxalinyl, substituted or unsubstituted benzimidazolyl, substituted or unsubstituted pyrazolyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted naphthidyl, substituted or unsubstituted phenanthrolinel, substituted or unsubstituted acridineyl, or substituted or unsubstituted carolinyl. When Ar3 has substituents, the substituents are deuterium atoms, cyano, nitro, halogen atoms, straight-chain or branched alkyl groups with 1 to 6 carbon atoms, straight-chain or branched alkoxy groups with 1 to 6 carbon atoms, alkenyl, aryloxy, arylalkoxy, phenyl, biphenyl, terphenyl, naphthyl, anthracene, fluorenyl, indene, pyrenyl, perylene, fluoranyl, benzo[9,10]phenanthryl, pyridyl, pyrimidinyl, triazine, thiophene, furanyl, pyrroleyl, quinoline, etc. Phosphoryl, isoquinolinyl, benzofuranyl, benzothiophenyl, indolyl, carbazoyl, benzoxazolyl, benzothiazoyl, quinoxolinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiaphenyl, carbazoyl, disubstituted amino group substituted with an aromatic hydrocarbon group or a fused polycyclic aromatic group, disubstituted amino group substituted with an aromatic heterocyclic group, or disubstituted amino group substituted with a substituent selected from aromatic hydrocarbon groups, fused polycyclic aromatic groups or aromatic heterocyclic groups. r1 and r2 represent integers from 0 to 4.

2. The organic electroluminescent element according to claim 1, characterized in that, The hole transport layer is a two-layer structure consisting of a first hole transport layer and a second hole transport layer, wherein the second hole transport layer contains the arylamine compound represented by the general formula (1).

3. The organic electroluminescent element according to claim 1 or 2, characterized in that, The arylamine compound represented by general formula (1) is an arylamine compound represented by the following general formula (1a). In the formula, A1 and Ar1 to Ar3 are defined as in the general formula (1).

4. The organic electroluminescent element according to claim 1 or 2, characterized in that, In the general formula (1), Ar3 is a substituted or unsubstituted phenyl group.

5. The organic electroluminescent element according to claim 1 or 2, characterized in that, In the general formula (1), A1 is a divalent group generated by removing two hydrogen atoms from benzene, whether substituted or unsubstituted.

6. The organic electroluminescent element according to claim 1 or 2, characterized in that, The light-emitting layer contains a cyan luminescent dopant.

7. The organic electroluminescent element according to claim 6, characterized in that, The cyan luminescent dopant is a pyrene derivative having a pyrene skeleton in its molecule.

8. The organic electroluminescent element according to claim 6, characterized in that, The cyan luminescent dopant is a compound represented by the following general formula (2) or general formula (3). In general formulas (2) and (3), Q1 to Q3 may be the same or different from each other, representing substituted or unsubstituted aromatic hydrocarbons, substituted or unsubstituted fused polycyclic aromatic hydrocarbons, or substituted or unsubstituted aromatic heterocycles; X represents B, P, P=O, or P=S; Y1 to Y3 may be the same or different from each other, and are selected from any one of N-R4, CR5R6, O, S, Se, or SiR7R8; R4 to R8 may be the same or different from each other, representing hydrogen atoms, deuterium atoms, fluorine atoms, chlorine atoms, cyano, nitro, straight-chain or branched alkyl groups with 1 to 6 carbon atoms that may have substituents, cycloalkyl groups with 5 to 10 carbon atoms that may have substituents, or straight-chain or branched alkyl groups with 2 to 6 carbon atoms that may have substituents. The groups can be branched alkenyl groups, straight-chain or branched alkoxy groups with 1 to 6 carbon atoms that may have substituents, cycloalkoxy groups with 5 to 10 carbon atoms that may have substituents, substituted or unsubstituted aromatic hydrocarbon groups, substituted or unsubstituted fused polycyclic aromatic groups, or substituted or unsubstituted aryloxy groups. In addition, R5 and R6, R7 and R8 can form rings by bonding between each group via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms. However, when Y1 to Y3 are N-R4, CR5R6, or SiR7R8, R4 to R8 can form rings by bonding with their respective adjacent Q1, Q2, or Q3 via substituted or unsubstituted methylene groups, oxygen atoms, sulfur atoms, monosubstituted amino groups, etc.

9. The organic electroluminescent element according to any one of claims 1 to 8, characterized in that, The luminescent layer contains anthracene derivatives having an anthracene skeleton in the molecule.

10. The organic electroluminescent element according to claim 9, characterized in that, The luminescent layer contains a host material, which is an anthracene derivative having an anthracene skeleton in the molecule.

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