organic electroluminescence element

Abstract

[Problem] The purpose of the present invention is to provide a material for organic EL elements having excellent hole injection and transport performance, electron blocking ability, stability in a thin film state, and durability. The purpose of the present invention is also to provide an organic EL element having high efficiency, low drive voltage, and a long lifespan, by combining excellent materials for organic EL elements such that the properties of each material can be effectively demonstrated. [Solution] A triarylamine compound having a specific structure according to the present invention has excellent hole injection and transport abilities, stability in a thin film state, and durability. Thus, said triarylamine compound having a specific structure is selected as a material for a hole transport layer, and consequently, holes injected from the positive electrode side can be transported efficiently. In addition, a variety of organic EL elements in which a light-emitting material having a specific structure and the like are combined exhibit good element properties.

Description

[Technical Field]

[0001] The present invention relates to an organic electroluminescent element, which is a self-emitting element suitable for various display devices, and more particularly to an organic electroluminescent element (hereinafter abbreviated as organic EL element) using a specific arylamine compound. [Background technology]

[0002] Organic EL elements are self-luminous elements, and therefore are brighter and more visible than liquid crystal elements, enabling clearer displays, and as such have been the subject of active research.

[0003] In 1987, C.W. Tang and his colleagues at Eastman Kodak Company made organic EL devices practical by developing a layered structure element in which various roles are assigned to each material. They layered a phosphor that can transport electrons and an organic material that can transport holes, and by injecting both charges into the phosphor layer to emit light, they achieved a brightness of 1000 cd / m at a voltage of 10 V or less. 2 Such high brightness has become possible (see, for example, Patent Documents 1 and 2).

[0004] To date, many improvements have been made to the practical application of organic EL devices, and the various roles of the laminated structure have been further subdivided, resulting in high efficiency and durability being achieved by electroluminescent devices in which an anode, a hole injection layer, a hole transport layer, an emitting layer, an electron transport layer, an electron injection layer, and a cathode are provided in this order on a substrate (see, for example, Non-Patent Document 1).

[0005] Furthermore, attempts have been made to utilize triplet excitons in order to further improve luminous efficiency, and the use of phosphorescent compounds has been investigated (see, for example, Non-Patent Document 2). In addition, elements that utilize light emission by thermally activated delayed fluorescence (TADF) have also been developed. In 2011, Adachi et al. of Kyushu University achieved an external quantum efficiency of 5.3% using an element that uses a thermally activated delayed fluorescence material. Ta( For example, see Non-Patent Document 3.。

[0006] The light-emitting layer can also be prepared by doping a charge-transporting compound, generally called a host material, with a fluorescent compound, a phosphorescent compound, or a material that emits delayed fluorescence. As described in the non-patent document, the selection of organic materials in an organic EL device has a significant effect on various properties of the device, such as efficiency and durability. Ru( For example, see Non-Patent Documents 1 to 3. 。

[0007] In organic EL devices, charges injected from both electrodes recombine in the light-emitting layer to emit light. However, it is important to efficiently transfer both charges (holes and electrons) to the light-emitting layer, making it necessary to achieve a device with excellent carrier balance. Furthermore, by improving hole injection and electron blocking properties (blocking electrons injected from the cathode), the probability of holes and electrons recombining can be increased, and by confining excitons generated in the light-emitting layer, high luminous efficiency can be achieved. Therefore, the role of hole transport materials is important, and hole transport materials with high hole injection properties, high hole mobility, high electron blocking properties, and high durability against electrons are required.

[0008] Furthermore, the heat resistance and amorphous nature of the material are also important factors in determining the lifespan of the element. Materials with low heat resistance will undergo thermal decomposition even at low temperatures due to the heat generated when the element is in operation, causing the material to deteriorate. Materials with low amorphous nature will undergo crystallization of the thin film even in a short period of time, causing the element to deteriorate. For this reason, the materials used must have high heat resistance and good amorphous nature.

[0009] N,N'-diphenyl-N,N'-di(α-naphthyl)benzidine (NPD) and various aromatic amine derivatives have been known to be hole transport materials used in organic EL devices up to now (see, for example, Patent Document 1 and Patent Document 2). NPD has good hole transport ability, but its glass transition temperature (Tg), which is an index of heat resistance, is low at 96°C, and crystallization occurs under high temperature conditions, resulting in a deterioration of device characteristics (see, for example, Non-Patent Document 4). In addition, among the aromatic amine derivatives described in the above patent documents, there are those with a hole mobility of 10 -3 cm 2 Although compounds with excellent mobility of 1 / Vs or more are known (see, for example, Patent Documents 1 and 2), their electron blocking properties are insufficient, so some electrons pass through the light-emitting layer, preventing improvements in luminous efficiency. For this reason, in order to further improve efficiency, materials with better electron blocking properties, more stable thin films, and high heat resistance are needed. Furthermore, although highly durable aromatic amine derivatives have been reported (see, for example, Patent Document 3), they were used as charge transport materials in electrophotographic photoreceptors, and there have been no examples of their use in organic EL devices.

[0010] Arylamine compounds having a substituted carbazole structure have been proposed as compounds with improved properties such as heat resistance and hole injection properties (see, for example, Patent Document 4 and Patent Document 5). However, in devices using these compounds in the hole injection layer or hole transport layer, although the heat resistance and luminous efficiency have been improved, they are still not sufficient, and further reduction in driving voltage and further improvement in luminous efficiency are required.

[0011] To improve the device characteristics and increase the yield of device production, there is a demand for devices that can recombine holes and electrons efficiently, have high luminous efficiency, low driving voltage, and have a long lifespan, by combining materials that have excellent hole and electron injection and transport properties, and have excellent thin film stability and durability.

[0012] Furthermore, in order to improve the device characteristics of organic EL devices, there is a demand for devices with a good carrier balance, high efficiency, low driving voltage, and long life by combining materials that have excellent hole and electron injection and transport properties, as well as thin film stability and durability. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] Japanese Patent Application Publication No. 8-048656 [Patent Document 2] Patent No. 3194657 [Patent Document 3] Patent No. 4943840 [Patent Document 4] Japanese Patent Application Laid-Open No. 2006-151979 [Patent Document 5] International Publication No. 2008 / 62636 [Patent Document 6] International Publication No. 2014 / 009310 [Non-patent literature]

[0014] [Non-Patent Document 1] Proceedings of the 9th Seminar of the Japan Society of Applied Physics, pp. 55-61 (2001) [Non-patent document 2] Proceedings of the 9th Seminar of the Japan Society of Applied Physics, pp. 23-31 (2001) [Non-patent document 3] Appl.Phys.Let.,98,083302(2011) [Non-patent document 4] Proceedings of the 3rd Regular Meeting of the Organic EL Symposium, pages 13-14 (2006) Summary of the Invention [Problem to be solved by the invention]

[0015] The object of the present invention is to provide a material for organic EL devices that has excellent hole injection / transport performance, electron blocking ability, and stability and durability in a thin film state, and further to provide an organic EL device that has high efficiency, low driving voltage, and long life by combining this material with various other materials for organic EL devices that have excellent hole and electron injection / transport performance, electron blocking ability, stability and durability in a thin film state so that the properties of each material can be effectively exhibited.

[0016] The physical properties that the organic compound to be provided by the present invention should have are: (1) good hole injection properties, (2) high hole mobility, (3) excellent electron blocking ability, (4) stable thin film state, and (5) excellent heat resistance. 、 can be given. The physical properties that the organic EL device to be provided by the present invention should have include (1) high luminous efficiency and power efficiency, (2) low luminous initiation voltage, (3) low practical driving voltage, and (4) long life. [Means for solving the problem]

[0017] To achieve the above object, the present inventors have focused on the fact that triarylamine compounds having a specific structure have excellent hole injection / transport capabilities, thin film stability, and durability, and have thoroughly investigated various triarylamine compounds and evaluated the properties of the organic EL devices they fabricated. As a result, the present inventors have discovered that when a triarylamine compound having a specific structure is used as a material for the hole transport layer, holes injected from the anode side can be efficiently transported. Furthermore, they have fabricated various organic EL devices in combination with light-emitting materials having specific structures, and evaluated the properties of the devices. As a result, they have completed the present invention.

[0018] That is, according to the present invention, the following organic EL device is provided.

[0019] 1) An organic EL device having at least a first hole transport layer, a second hole transport layer, a blue light-emitting layer, and an electron transport layer, arranged in this order from the anode side, between an anode and a cathode, wherein at least one layer of the second hole transport layer or a laminated film arranged between the first hole transport layer and the electron transport layer contains a triarylamine compound represented by the following general formula (1):

[0020] [ka] (1)

[0021] (In the formula, A, B, and C may be the same or different and represent a monovalent group having the dashed line portion shown in the following general formula (2-1) as the bonding site, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group. However, A, B, and C cannot all simultaneously be a monovalent group shown in the following general formula (2-1).)

[0022] [ka] (2-1)

[0023] (In the formula, the dashed line represents a bonding site. R represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, an optionally substituted linear or branched alkyl group of 1 to 6 carbon atoms, an optionally substituted cycloalkyl group of 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group of 2 to 6 carbon atoms, an optionally substituted linear or branched alkyloxy group of 1 to 6 carbon atoms, an optionally substituted cycloalkyloxy group of 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. n is the number of R. , and an integer of 0 to 3. When n is 2 or 3, multiple Rs bonded to the same benzene ring may be the same or different from each other, and may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring. L represents a substituted or unsubstituted aromatic hydrocarbon divalent group, a substituted or unsubstituted aromatic heterocyclic divalent group, or a substituted or unsubstituted condensed polycyclic aromatic divalent group, and m represents an integer of 1 to 3. When m is 2 or 3, Ls may be the same or different from each other. Ar1 and Ar2 may be the same or different from each other, and represent a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted condensed polycyclic aromatic group.

[0024] 2) The organic EL device according to 1) above, wherein the general formula (2-1) is a monovalent group represented by the following general formula (2-2):

[0025] [ka] (2-2)

[0026] (In the formula, the dashed line represents a bonding site, and Ar1, Ar2, L, m, n, and R are as defined in the general formula (2-1) above.)

[0027] 3) The organic EL device according to 1) above, wherein the general formula (2-1) is a monovalent group represented by the following general formula (2-3):

[0028] [ka] (2-3)

[0029] (In the formula, the dashed line represents a bonding site, and Ar1, Ar2, n, and R are as defined in the general formula (2-1) above. p represents 0 or 1.)

[0030] 4) The organic EL device according to 1) above, wherein the general formula (2-1) is a monovalent group represented by the following general formula (2-4):

[0031] [ka] (2-4)

[0032] (In the formula, the dashed line represents a bonding site, and Ar1 and Ar2 are as defined in the general formula (2-1) above. p represents 0 or 1.)

[0033] 5) The organic EL device according to any one of the above 1) to 4), wherein the blue light-emitting layer contains a blue light-emitting dopant.

[0034] 6) The organic EL device according to 5) above, wherein the blue light-emitting dopant is a compound represented by the following general formula (3-1) or (3-2):

[0035] [ka] (3-1)

[0036] [ka] (3-2)

[0037] In the general formulas (3-1) and (3-2), Q1 to Q3 may be the same or different from one another and represent a substituted or unsubstituted aromatic hydrocarbon, a substituted or unsubstituted fused polycyclic aromatic, or a substituted or unsubstituted aromatic heterocycle. X represents B, P, P=O, or P=S. Y1 to Y3 may be the same or different from one another and represent any one selected from N-R4, CR5R6, O, S, Se, or SiR7R8, where R4 to R8 may be the same or different from one another and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent, a linear or branched alkyl group having 2 to 6 carbon atoms which may have a substituent, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent, a cycloalkyl ... represents an alkenyl group, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent, a cycloalkyloxy group having 5 to 10 carbon atoms which may have a substituent, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group. Furthermore, R5 and R6, and R7 and R8 may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring. Here, when Y1 to Y3 are N-R4, CR5R6, or SiR7R8, R4 to R8 may be bonded to the adjacent Q1, Q2, or Q3 via a linking group such as a substituted or unsubstituted methylene group, an oxygen atom, a sulfur atom, or a monosubstituted amino group to form a ring.

[0038] 7) The organic EL device according to any one of 1) to 6) above, wherein the blue light-emitting layer contains an anthracene derivative having an anthracene skeleton in the molecule.

[0039] 8) The organic EL device according to 7) above, wherein the blue light-emitting layer contains a host material which is an anthracene derivative having an anthracene skeleton in the molecule.

[0040] Specific examples of the "aromatic hydrocarbon group", "aromatic heterocyclic group", or "condensed polycyclic aromatic group" in the "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group", or "substituted or unsubstituted condensed polycyclic aromatic group" represented by R in the general formula (2-1) include a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a fluorenyl group, a spirobifluorenyl group, an indenyl group, a pyrenyl group, a perylenyl group, a fluoranthenyl group, a triphenylenyl group, a pyridyl group, a pyrimidinyl group, a phenyl ...fluorenyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a fluorimidinyl group, a In addition to a pyrazinyl group, a triazinyl group, a furyl group, a pyrrolyl group, a thienyl group, a quinolyl group, an isoquinolyl group, a benzofuranyl group, a benzothienyl group, an indolyl group, a carbazolyl group, a benzoxazolyl group, a benzothiazolyl group, a quinoxalinyl group, a benzimidazolyl group, a pyrazolyl group, a dibenzofuranyl group, a dibenzothienyl group, a naphthyridinyl group, a phenanthrolinyl group, an acridinyl group, a carbolinyl group, and the like, an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 2 to 30 carbon atoms can be selected. Furthermore, when a plurality of these groups are bonded to the same benzene ring, they may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring, or each group may be bonded to the benzene ring to which it is bonded via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring.

[0041] Specific examples of the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in the general formula (2-1) include a deuterium atom, a cyano group, a nitro group; a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom; a silyl group such as a trimethylsilyl group or a triphenylsilyl group; a linear or branched alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, or a propyl group; a linear or branched alkyloxy group having 1 to 6 carbon atoms such as a methyloxy group, an ethyloxy group, or a propyloxy group; an alkenyl group such as a vinyl group or an allyl group; an aryloxy group such as a phenyloxy group or a tolyloxy group; or an arylalkyloxy group such as a benzyloxy group or a phenethyloxy group. aromatic hydrocarbon groups or condensed polycyclic aromatic groups such as a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a fluorenyl group, a spirobifluorenyl group, an indenyl group, a pyrenyl group, a perylenyl group, a fluoranthenyl group, or a triphenylenyl group; and aromatic heterocyclic groups such as a pyridyl group, a thienyl group, a furyl group, a pyrrolyl group, a quinolyl group, an isoquinolyl group, a benzofuranyl group, a benzothienyl group, an indolyl group, a carbazolyl group, a benzoxazolyl group, a benzothiazolyl group, a quinoxalinyl group, a benzimidazolyl group, a pyrazolyl group, a dibenzofuranyl group, a dibenzothienyl group, or a carbolinyl group, and these substituents may be further substituted with the substituents exemplified above. Furthermore, these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0042] Specific examples of the "C-C linear or branched alkyl group," "C-C cycloalkyl group," or "C-C linear or branched alkenyl group" in the "C-C linear or branched alkyl group which may have a substituent," "C-C cycloalkyl group which may have a substituent," or "C-C linear or branched alkenyl group which may have a substituent" represented by R in the general formula (2-1) 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, and 2-butenyl. Furthermore, when a plurality of these groups are bonded to the same benzene ring, they may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring, or each group may be bonded to the benzene ring to which it is bonded via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring.

[0043] Examples of the "substituent" in the "substituted linear or branched alkyl group having 1 to 6 carbon atoms," "substituted cycloalkyl group having 5 to 10 carbon atoms," or "substituted linear or branched alkenyl group having 2 to 6 carbon atoms," represented by R in the general formula (2-1), specifically include a deuterium atom, a cyano group, a nitro group; a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom; a silyl group such as a trimethylsilyl group or a triphenylsilyl group; a linear or branched alkyloxy group having 1 to 6 carbon atoms such as a methyloxy group, an ethyloxy group, or a propyloxy group; an alkenyl group such as a vinyl group or an allyl group; an aryloxy group such as a phenyloxy group or a tolyloxy group; an alkyl group such as a benzyloxy group or a phenethyloxy group; aromatic hydrocarbon groups or condensed polycyclic aromatic groups such as a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a fluorenyl group, a spirobifluorenyl group, an indenyl group, a pyrenyl group, a perylenyl group, a fluoranthenyl group, or a triphenylenyl group; and aromatic heterocyclic groups such as a pyridyl group, a thienyl group, a furyl group, a pyrrolyl group, a quinolyl group, an isoquinolyl group, a benzofuranyl group, a benzothienyl group, an indolyl group, a carbazolyl group, a benzoxazolyl group, a benzothiazolyl group, a quinoxalinyl group, a benzimidazolyl group, a pyrazolyl group, a dibenzofuranyl group, a dibenzothienyl group, or a carbolinyl group, and these substituents may be further substituted with the substituents exemplified above. Furthermore, these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0044] Specific examples of the "C1 to C6 straight-chain or branched alkyloxy group" or "C5 to C10 cycloalkyloxy group" in the "C1 to C6 linear or branched alkyloxy group which may have a substituent" or "C5 to C10 cycloalkyloxy group which may have a substituent" represented by R in the general formula (2-1) include methyloxy, ethyloxy, n-propyloxy, isopropyloxy, n-butyloxy, tert-butyloxy, n-pentyloxy, n-hexyloxy, cyclopentyloxy, cyclohexyloxy, cycloheptyloxy, cyclooctyloxy, 1-adamantyloxy, 2-adamantyloxy, and the like. Furthermore, when a plurality of these groups are bonded to the same benzene ring, they may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring, or each group may be bonded to the benzene ring to which it is bonded via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring.

[0045] Specific examples of the "substituent" in the "substituted linear or branched alkyloxy group having 1 to 6 carbon atoms" or "substituted cycloalkyloxy group having 5 to 10 carbon atoms" represented by R in the general formula (2-1) include a deuterium atom, a cyano group, a nitro group; a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom; a silyl group such as a trimethylsilyl group or a triphenylsilyl group; a linear or branched alkyloxy group having 1 to 6 carbon atoms such as a methyloxy group, an ethyloxy group, or a propyloxy group; an alkenyl group such as a vinyl group or an allyl group; an aryloxy group such as a phenyloxy group or a tolyloxy group; an arylalkyloxy group such as a benzyloxy group or a phenethyloxy group; a phenyl and aromatic hydrocarbon groups or condensed polycyclic aromatic groups such as a biphenylyl group, a terphenylyl group, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a fluorenyl group, a spirobifluorenyl group, an indenyl group, a pyrenyl group, a perylenyl group, a fluoranthenyl group, or a triphenylenyl group; and aromatic heterocyclic groups such as a pyridyl group, a thienyl group, a furyl group, a pyrrolyl group, a quinolyl group, an isoquinolyl group, a benzofuranyl group, a benzothienyl group, an indolyl group, a carbazolyl group, a benzoxazolyl group, a benzothiazolyl group, a quinoxalinyl group, a benzimidazolyl group, a pyrazolyl group, a dibenzofuranyl group, a dibenzothienyl group, or a carbolinyl group, and these substituents may be further substituted with the substituents exemplified above. Furthermore, these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0046] Specific examples of the "aryloxy group" in the "substituted or unsubstituted aryloxy group" represented by R in general formula (2-1) include a phenyloxy group, a biphenylyloxy group, a terphenylyloxy group, a naphthyloxy group, an anthracenyloxy group, a phenanthrenyloxy group, a fluorenyloxy group, an indenyloxy group, a pyrenyloxy group, and a perylenyloxy group. Furthermore, when a plurality of these groups are bonded to the same benzene ring, they may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring, or each group may be bonded to the benzene ring to which it is bonded via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring.

[0047] Examples of the "substituent" in the "substituted aryloxy group" represented by R in the general formula (2-1) include the same as those exemplified as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in the general formula (2-1), and these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0048] Examples of the "aromatic hydrocarbon group", "aromatic heterocyclic group", or "fused polycyclic aromatic group" in the "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group", or "substituted or unsubstituted fused polycyclic aromatic group" represented by Ar1 and Ar2 in general formula (2-1) include the same as those exemplified as the "aromatic hydrocarbon group", "aromatic heterocyclic group", or "fused polycyclic aromatic group" in the "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group", or "substituted or unsubstituted fused polycyclic aromatic group" represented by R in the above general formula (2-1).

[0049] Examples of the "substituents" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by Ar1 and Ar2 in general formula (2-1) include the same as those shown as the "substituents" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in general formula (2-1) above, and these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0050] Examples of the "aromatic hydrocarbon group", "aromatic heterocyclic group", or "fused polycyclic aromatic group" in the "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group", or "substituted or unsubstituted fused polycyclic aromatic group" represented by A, B, and C in general formula (1) include the same as those exemplified as the "aromatic hydrocarbon group", "aromatic heterocyclic group", or "fused polycyclic aromatic group" in the "substituted or unsubstituted aromatic hydrocarbon group", "substituted or unsubstituted aromatic heterocyclic group", or "substituted or unsubstituted fused polycyclic aromatic group" represented by R in general formula (2-1) above.

[0051] Examples of the "substituents" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by A, B, and C in general formula (1) include the same as those shown as the "substituents" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in general formula (2-1) above, and these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0052] Specific examples of the "aromatic hydrocarbon", "aromatic heterocycle", or "condensed polycyclic aromatic" in the "substituted or unsubstituted aromatic hydrocarbon divalent group", "substituted or unsubstituted aromatic heterocycle", or "substituted or unsubstituted condensed polycyclic aromatic divalent group" represented by L in the general formula (2-1) include benzene, biphenyl, terphenyl, tetrakisphenyl, styrene, and the like. Examples of the aromatic hydrocarbon include phenylene, naphthalene, anthracene, acenaphthalene, fluorene, phenanthrene, indane, pyrene, triphenylene, pyridine, pyrimidine, triazine, pyrrole, furan, thiophene, quinoline, isoquinoline, benzofuran, benzothiophene, indoline, carbazole, carboline, benzoxazole, benzothiazole, quinoxaline, benzimidazole, pyrazole, dibenzofuran, dibenzothiophene, naphthyridine, phenanthroline, and acridine. And, "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 condensed polycyclic aromatic ring" represented by L in the general formula (2-1) "Divalent aromatic hydrocarbon radical," "Divalent aromatic heterocyclic radical," or "Divalent condensed polycyclic aromatic radical" represents a divalent group obtained by removing two hydrogen atoms from the above-mentioned "aromatic hydrocarbon," "aromatic heterocycle," or "condensed polycyclic aromatic ring."

[0053] Examples of the "substituent" in the "divalent substituted aromatic hydrocarbon group," "divalent substituted aromatic heterocyclic group," or "divalent substituted fused polycyclic aromatic group" represented by L in general formula (2-1) include the same as those exemplified as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in general formula (2-1) above, and these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0054] In the triarylamine compound represented by general formula (1), it is preferable that at least one of A, B, and C is a monovalent group represented by general formula (2-1).

[0055] In the triarylamine compound represented by general formula (1), the monovalent group represented by general formula (2-1) is preferably a monovalent group represented by general formula (2-2), more preferably a monovalent group represented by general formula (2-3), and even more preferably a monovalent group represented by general formula (2-4).

[0056] In the triarylamine compound represented by general formula (1), Ar1 and / or Ar2 in general formulae (2-1) to (2-4) are preferably "substituted or unsubstituted aromatic hydrocarbon groups" or "substituted or unsubstituted fused polycyclic aromatic groups", more preferably substituted or unsubstituted phenyl groups, naphthyl groups, or biphenylyl groups, and even more preferably unsubstituted phenyl groups or naphthyl groups. In the triarylamine compound represented by general formula (1), L in general formulas (2-1) to (2-2) is preferably an "unsubstituted aromatic hydrocarbon divalent group," "unsubstituted aromatic heterocyclic divalent group," or "unsubstituted fused polycyclic aromatic divalent group." Furthermore, it is preferably a divalent group obtained by removing two hydrogen atoms from an "aromatic hydrocarbon" or a "fused polycyclic aromatic," more preferably a divalent group obtained by removing two hydrogen atoms from an "aromatic hydrocarbon," and even more preferably a divalent group obtained by removing two hydrogen atoms from benzene (phenylene group).

[0057] In the triarylamine compound represented by the general formula (1), it is preferable that the number n of the substituents R in the general formula (2-1) is zero (0), that is, that the compound has no substituents R. In the triarylamine compound represented by the general formula (1), the number m of the divalent groups L in the general formula (2-1) is preferably 1 or 2.

[0058] Specific examples of the "aromatic hydrocarbon," "condensed polycyclic aromatic," or "aromatic heterocycle" in the "substituted or unsubstituted aromatic hydrocarbon," "substituted or unsubstituted condensed polycyclic aromatic," or "substituted or unsubstituted aromatic heterocycle" represented by Q1 to Q3 in general formula (3-1) and general formula (3-2) include benzene, naphthalene, anthracene, fluorene, phenanthrene, pyridine, pyrimidine, triazine, pyrrole, furan, thiophene, quinoline, isoquinoline, indene, benzofuran, benzothiophene, indole, indoline, carbazole, carboline, benzoxazole, benzothiazole, quinoxaline, benzimidazole, pyrazole, dibenzofuran, dibenzothiophene, naphthyridine, phenanthroline, and acridine.

[0059] In addition, these Based on may have a substituent, and examples of the substituent include the same as those exemplified as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in the general formula (2-1). Furthermore, these substituents may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring.

[0060] In the general formula (3-1) and the general formula (3-2), X represents B, P, P=O, or P=S. B represents a boron atom, P represents a phosphorus atom, and P=O represents a phosphorus atom bonded to an oxygen atom by a double bond, or TaP =S is defined as a phosphorus atom with a sulfur atom attached by a double bond.

[0061] In general formula (3-1) and general formula (3-2), Y1 to Y3 may be the same or different and are any one selected from N-R4, CR5R6, O, S, Se, and 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. Here, R4 to R8 may each be bonded to the adjacent Q1, Q2, or Q3 via a linking group such as a substituted or unsubstituted methylene group, oxygen atom, sulfur atom, or monosubstituted amino group to form a ring, i.e., Q1 when Y1 is N-R4, CR5R6, or SiR7R8, Q2 or Q3 when Y2 is N-R4, CR5R6, or SiR7R8, or Q3 when Y3 is N-R4, CR5R6, or SiR7R8. Furthermore, R5 and R6, and R7 and R8 may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring. The definitions of R4 to R8 will be explained in more detail below.

[0062] When Y1 to Y3 in the general formula (3-1) and the general formula (3-2) are N-R4, CR5R6, or SiR7R8, the "linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent", the "cycloalkyl group having 5 to 10 carbon atoms which may have a substituent", or the "linear or branched alkyl group having 1 to 6 carbon atoms", "the cycloalkyl group having 5 to 10 carbon atoms which may have a substituent", or the "linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent" represented by R4 to R8 are Specific examples of the "cycloalkyl group having 5 to 10 carbon atoms" or the "linear or branched alkenyl group having 2 to 6 carbon atoms" include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, an n-hexyl group, a cyclopentyl group, a cyclohexyl group, a 1-adamantyl group, a 2-adamantyl group, a vinyl group, an allyl group, an isopropenyl group, and a 2-butenyl group.

[0063] In addition, these Based onmay have a substituent, and examples of the substituent include the same as those exemplified as the "substituent" in the "substituted linear or branched alkyl group having 1 to 6 carbon atoms," "substituted cycloalkyl group having 5 to 10 carbon atoms," or "substituted linear or branched alkenyl group having 2 to 6 carbon atoms" represented by R in the general formula (2-1).

[0064] When Y1 to Y3 in general formula (3-1) and general formula (3-2) are N-R4, CR5R6, or SiR7R8, specific examples of the "linear or branched alkyloxy group having 1 to 6 carbon atoms which may have a substituent" or "cycloalkyloxy group having 5 to 10 carbon atoms" represented by R4 to R8 include a methyloxy group, an ethyloxy group, an n-propyloxy group, an isopropyloxy group, an n-butyloxy group, a tert-butyloxy group, an n-pentyloxy group, an n-hexyloxy group, a cyclopentyloxy group, a cyclohexyloxy group, a cycloheptyloxy group, a cyclooctyloxy group, a 1-adamantyloxy group, and a 2-adamantyloxy group.

[0065] These groups may have a substituent, and examples of the substituent include the same as those exemplified as the "substituent" in the "substituted linear or branched alkyloxy group having 1 to 6 carbon atoms" or the "substituted cycloalkyloxy group having 5 to 10 carbon atoms" represented by R in the general formula (2-1).

[0066] When Y1 to Y3 in general formula (3-1) and general formula (3-2) are N-R4, CR5R6, or SiR7R8, specific examples of the "aromatic hydrocarbon group" or "condensed polycyclic aromatic group" in the "substituted or unsubstituted aromatic hydrocarbon group" or "substituted or unsubstituted condensed polycyclic aromatic group" represented by R4 to R8 include a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, an anthracenyl group, and a phenanthrenyl group.

[0067] These groups may have a substituent, and examples of the substituent include the same as those exemplified as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in the general formula (2-1).

[0068] When Y1 to Y3 in general formula (3-1) and general formula (3-2) are N-R4, CR5R6, or Si-R7R8, specific examples of the "aryloxy group" in the "substituted or unsubstituted aryloxy group" represented by R4 to R8 include a phenyloxy group, a biphenylyloxy group, a terphenylyloxy group, a naphthyloxy group, an anthracenyloxy group, a phenanthrenyloxy group, a fluorenyloxy group, an indenyloxy group, a pyrenyloxy group, and a perylenyloxy group.

[0069] These groups may have a substituent, and examples of the substituent include the same as those exemplified as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by R in the general formula (2-1).

[0070] In general formulas (3-1) and (3-2), the "aromatic hydrocarbon", "condensed polycyclic aromatic" or "aromatic heterocycle" in the "substituted or unsubstituted aromatic hydrocarbon", "substituted or unsubstituted condensed polycyclic aromatic" or "substituted or unsubstituted aromatic heterocycle" of Q1 to Q3 is preferably benzene, naphthalene, phenanthrene, pyridine, pyrimidine, indene, benzofuran, benzothiophene or indole, more preferably benzene or naphthalene.

[0071] In general formulas (3-1) and (3-2), when Y1 to Y3 are N-R4, CR5R6, or SiR7R8, R4 to R8 are preferably an optionally substituted linear or branched alkyl group of 1 to 6 carbon atoms, an optionally substituted cycloalkyl group of 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group of 2 to 6 carbon atoms, an optionally substituted linear or branched alkyloxy group of 1 to 6 carbon atoms, a optionally substituted cycloalkyloxy group of 5 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted aryloxy group, and R4 is more preferably an optionally substituted linear or branched alkyl group of 1 to 6 carbon atoms, a cycloalkyl group of 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group of 2 to 6 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted condensed polycyclic aromatic group. In general formula (3-1) and general formula (3-2), Y1 is preferably N-R4, O, or S, and more preferably O or S. In general formula (3-1) and general formula (3-2), at least one of Y2 and Y3 is preferably N-R4, and more preferably both are N-R4. R4 is preferably a "substituted or unsubstituted aromatic hydrocarbon group" or a "substituted or unsubstituted fused polycyclic aromatic group," and more preferably a substituted or unsubstituted phenyl group, biphenylyl group, terphenylyl group, or naphthyl group. [Effects of the Invention]

[0072] The triarylamine compound of the present invention represented by the general formula (1) has the following properties: (1) good hole injection properties, (2) high hole mobility, (3) excellent electron blocking ability, (4) stable thin film state, and (5) excellent heat resistance. Therefore, it is suitable for use as a constituent material of the hole transport layer of the organic EL device of the present invention.

[0073] The organic EL device of the present invention, which uses the triarylamine compound represented by the general formula (1) according to the present invention as a constituent material of the hole transport layer, has a higher hole mobility than conventional hole transport materials, an excellent electron blocking ability, excellent amorphous properties, and a stable thin film state, and therefore can realize an organic EL device with high efficiency, a low driving voltage, and a long life.

[0074] Furthermore, in the present invention, the hole transport layer has a two-layer structure consisting of a first hole transport layer and a second hole transport layer, and the second hole transport layer located on the light-emitting layer side is formed from the triarylamine compound of general formula (1). This makes it possible to make the most of the electron blocking ability of the triarylamine compound, thereby realizing an organic EL device with higher efficiency and longer life.

[0075] Furthermore, in the present invention, the organic EL device of the present invention uses the triarylamine compound represented by the general formula (1) as a constituent material in at least one layer of either the second hole transport layer or the laminated film disposed between the first hole transport layer and the electron transport layer. Since the triarylamine compound has excellent amorphous properties and is stable in a thin film state, it is possible to realize an organic EL device with high efficiency, a low driving voltage, and a long life. [Brief explanation of the drawings]

[0076] [Figure 1] FIG. 1 shows structural formulas of compounds 1-1 to 1-12 as examples of triarylamine compounds represented by general formula (1). [Figure 2] FIG. 1 shows the structural formulas of compounds 1-13 to 1-24 as examples of triarylamine compounds represented by general formula (1). [Figure 3] FIG. 1 shows the structural formulas of compounds 1-25 to 1-36 as examples of triarylamine compounds represented by general formula (1). [Figure 4] FIG. 1 shows the structural formulas of compounds 1-37 to 1-48 as examples of triarylamine compounds represented by general formula (1). [Figure 5] FIG. 1 shows the structural formulas of compounds 1-49 to 1-60, which are examples of triarylamine compounds represented by general formula (1). [Figure 6] FIG. 1 shows the structural formulas of compounds 1-61 to 1-72 as examples of triarylamine compounds represented by general formula (1). [Figure 7] FIG. 1 shows the structural formulas of compounds 1-73 to 1-84 as examples of triarylamine compounds represented by general formula (1). [Figure 8] FIG. 1 shows the structural formulas of compounds 1-85 to 1-95 as examples of triarylamine compounds represented by general formula (1). [Figure 9] FIG. 1 shows the structural formulas of compounds 1-96 to 1-107 as examples of triarylamine compounds represented by general formula (1). [Figure 10] FIG. 1 shows the structural formulas of compounds 1-108 to 1-119 as examples of triarylamine compounds represented by general formula (1). [Figure 11] FIG. 1 shows the structural formulas of compounds 1-120 to 1-131 as examples of triarylamine compounds represented by general formula (1). [Figure 12] FIG. 1 shows the structural formulas of compounds 1-132 to 1-142 as examples of triarylamine compounds represented by general formula (1). [Figure 13] FIG. 1 shows the structural formulas of compounds 1-143 to 1-154 as examples of triarylamine compounds represented by general formula (1). [Figure 14]FIG. 1 shows the structural formulas of compounds 1-155 to 1-166 as examples of triarylamine compounds represented by general formula (1). [Figure 15] FIG. 1 shows the structural formulas of compounds 1-167 to 1-178 as examples of triarylamine compounds represented by general formula (1). [Figure 16] FIG. 1 shows the structural formulas of compounds 1-179 to 1-190, which are examples of triarylamine compounds represented by general formula (1). [Figure 17] FIG. 1 shows the structural formulas of compounds 1-191 to 1-201 as examples of triarylamine compounds represented by general formula (1). [Figure 18] FIG. 1 shows the structures of compounds 3-1-1 to 3-1-9 as examples of compounds represented by general formula (3-1). [Figure 19] FIG. 1 shows the structural formulas of compounds 3-1-10 to 3-1-24 as examples of compounds represented by general formula (3-1). [Figure 20] FIG. 1 shows the structures of compounds 3-2-1 to 3-2-6 as examples of compounds represented by general formula (3-2). [Figure 21] 1 is a diagram showing an example of the configuration of an organic EL element of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0077] Among the triarylamine compounds represented by the general formula (1) that are suitably used in the organic EL device of the present invention, specific examples of preferred compounds are shown in FIGS. 1 to 17, but the present invention is not limited to these compounds.

[0078] Among the compounds represented by the general formula (3-1) or the general formula (3-2) that are suitably used in the organic EL device of the present invention, specific examples of preferred compounds are shown in Figures 18 to 19 and Figure 20, respectively, but the present invention is not limited to these compounds.

[0079] The triarylamine compounds represented by general formula (1) were purified by column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization or crystallization using solvents, sublimation purification, etc. The compounds were identified by NMR analysis. The glass transition temperature (Tg) and work function were measured as physical properties. The glass transition temperature (Tg) is an index of the stability of the thin film state, and the work function is an index of hole transport properties and electronic In addition, the compounds used in the organic EL device of the present invention are purified by column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization or crystallization using a solvent, etc., and finally purified by sublimation purification.

[0080] The glass transition temperature (Tg) was measured using a high-sensitivity differential scanning calorimeter (DSC3100SA, manufactured by Bruker AXS) using powder.

[0081] The work function was determined by forming a 100 nm thin film on an ITO substrate and using an ionization potential measuring device (PYS-202, manufactured by Sumitomo Heavy Industries, Ltd.).

[0082] The organic EL device of the present invention may have a structure comprising, in order on a substrate, an anode, a hole transport layer, an emitting layer, an electron transport layer, and a cathode; a hole injection layer between the anode and the hole transport layer; a hole blocking layer between the emitting layer and the electron transport layer; or an electron injection layer between the electron transport layer and the cathode. In these multilayer structures, some organic layers may be omitted or may serve as both layers. For example, a layer may serve as both a hole injection layer and a hole transport layer, or a layer may serve as both an electron injection layer and an electron transport layer. Two or more organic layers having the same function may also be stacked, such as a two-layer hole transport layer, a two-layer emitting layer, or a two-layer electron transport layer. The organic EL device of the present invention preferably has a two-layer structure in which the hole transport layer is a first hole transport layer and a second hole transport layer. In this case, the second hole transport layer is preferably adjacent to the emitting layer, and in this case, it can function as an electron blocking layer.

[0083] The anode of the organic EL device of the present invention is made of an electrode material having a large work function, such as ITO or gold. An arylamine compound having a structure in which two triphenylamine structures are linked in the molecule by a single bond or a divalent group containing no heteroatom is preferred. Materials that can be used include starburst-type triphenylamine derivatives, various triphenylamine tetramers, porphyrin compounds such as copper phthalocyanine, acceptor heterocyclic compounds such as hexacyanoazatriphenylene, and coating-type polymer materials. These materials can be formed into thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0084] The triarylamine compound represented by the general formula (1) is used for the hole-transport layer of the organic EL device of the present invention. Examples of hole-transporting materials that can be mixed with or used simultaneously with the triarylamine compound represented by the general formula (1) include benzidine derivatives such as N,N'-diphenyl-N,N'-di(m-tolyl)benzidine (TPD), N,N'-diphenyl-N,N'-di(α-naphthyl)benzidine (NPD), and N,N,N',N'-tetrabiphenylylbenzidine, 1,1-bis[4-(di-4-tolylamino)phenyl]cyclohexane (TAPC), and various triphenylamine derivatives such as arylamine compounds having a structure in which four triphenylamine structures are linked in the molecule by a divalent group not containing a single bond or a heteroatom, or arylamine compounds having a structure in which two triphenylamine structures are linked in the molecule by a divalent group not containing a single bond or a heteroatom. These may be formed as a film by themselves, or may be mixed with other materials and formed as a single layer. often The material may be a laminated structure of layers formed independently, layers formed in a mixture, or layers formed in a mixture with layers formed independently. These materials can be formed into thin films by known methods such as vapor deposition, spin coating, ink jetting, etc. 。

[0085] Furthermore, in the hole injection layer or hole transport layer, materials that are typically used for the layer can be further doped with P, such as trisbromophenylaminehexachloroantimony or radialene derivatives (see, for example, Patent Document 6), or polymer compounds having a structure of a benzidine derivative such as TPD in their partial structure.

[0086] When the hole-transport layer of the organic EL device of the present invention has a two-layer structure consisting of a first hole-transport layer and a second hole-transport layer, the second hole-transport layer located on the light-emitting layer side uses a triarylamine compound represented by the general formula (1). Examples of hole-transporting materials that can be mixed with or used simultaneously with the triarylamine compound represented by the general formula (1) include compounds with electron blocking properties, such as carbazole derivatives such as 4,4',4"-tri(N-carbazolyl)triphenylamine (TCTA), 9,9-bis[4-(carbazol-9-yl)phenyl]fluorene, 1,3-bis(carbazol-9-yl)benzene (mCP), and 2,2-bis(4-carbazol-9-ylphenyl)adamantane (Ad-Cz), and compounds having a triphenylsilyl group and a triarylamine structure, such as 9-[4-(carbazol-9-yl)phenyl]-9-[4-(triphenylsilyl)phenyl]-9H-fluorene.

[0087] These may be formed as a film by themselves, or may be mixed with other materials and formed as a single layer. often The material may be a laminate of layers formed independently, layers formed by mixing, or layers formed by mixing layers formed independently. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and ink jet printing.

[0088] The compound represented by the general formula (3-1) or (3-2) is preferably used as the light-emitting layer of the organic EL device of the present invention. In addition, metal complexes of quinolinol derivatives such as Alq3, various metal complexes, anthracene derivatives, bisstyrylbenzene derivatives, pyrene derivatives, oxazole derivatives, polyparaphenylenevinylene derivatives, etc. can be used. The light-emitting layer may also be composed of a host material and a dopant material. oftenIn this case, an anthracene derivative having an anthracene skeleton in the molecule is preferably used as the host material, but other materials that can be used include various metal complexes, bisstyrylbenzene derivatives, pyrene derivatives, oxazole derivatives, polyparaphenylenevinylene derivatives, heterocyclic compounds having an indole ring as a partial structure of a fused ring, heterocyclic compounds having a carbazole ring as a partial structure of a fused ring, carbazole derivatives, thiazole derivatives, benzimidazole derivatives, and polydialkylfluorene derivatives. As the dopant material, a compound represented by the general formula (3-1) or (3-2) is preferably used, but other materials that can be used include pyrene derivatives having a pyrene skeleton in the molecule, heterocyclic compounds having an indole ring as a partial structure of a fused ring, heterocyclic compounds having a carbazole ring as a partial structure of a fused ring, carbazole derivatives, thiazole derivatives, benzimidazole derivatives, polydialkylfluorene derivatives, quinacridone, coumarin, rubrene, perylene, and derivatives thereof, benzopyran derivatives, indenophenanthrene derivatives, rhodamine derivatives, aminostyryl derivatives, etc. These may be used alone to form a film, or may be mixed with other materials to form a single layer. often Alternatively, the layer may be a laminated structure of layers formed independently, layers formed in a mixture, or layers formed in a mixture with layers formed independently.

[0089] Phosphorescent emitters can also be used as light-emitting materials. Examples of phosphorescent emitters include metal complexes of iridium and platinum. Green emitters such as Ir(ppy)3, blue emitters such as FIrpic and FIr6, and red emitters such as Btp2Ir(acac) are commonly used. Anthracene derivatives with an anthracene skeleton are preferred as host materials. Other examples of hole-injecting and transporting host materials include carbazole derivatives such as 4,4'-di(N-carbazolyl)biphenyl (CBP), TCTA, and mCP. Electron-transporting host materials such as p-bis(triphenylsilyl)benzene (UGH2) and 2,2',2''-(1,3,5-phenylene)-tris(1-phenyl-1H-benzimidazole) (TPBI) can be used to fabricate high-performance organic EL devices.

[0090] In order to avoid concentration quenching, the phosphorescent light-emitting material is preferably doped into the host material by co-evaporation in a range of 1 to 30 weight percent based on the entire light-emitting layer.

[0091] It is also possible to use materials that emit delayed fluorescence, such as CDCB derivatives such as PIC-TRZ, CC2TA, PXZ-TRZ, and 4CzIPN, as light-emitting materials. Ru( For example, see Non-Patent Document 3. 。

[0092] These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and ink jet printing.

[0093] For the hole-blocking layer of the organic EL device of the present invention, compounds having hole-blocking properties can be used, such as phenanthroline derivatives such as bathocuproine (BCP) and metal complexes of quinolinol derivatives such as aluminum (III) bis(2-methyl-8-quinolinato)-4-phenylphenolate (BAlq), as well as various rare earth complexes, triazole derivatives, triazine derivatives, and oxadiazole derivatives. These materials may also serve as materials for the electron-transporting layer. These materials may be formed alone or mixed with other materials to form a single layer. often The material may be a laminate of layers formed independently, layers formed by mixing, or layers formed by mixing layers formed independently. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and ink jet printing.

[0094] For the electron transport layer of the organic EL device of the present invention, metal complexes of quinolinol derivatives such as 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, pyridoindole derivatives, phenanthroline derivatives, silole derivatives, etc. can be used. These may be formed into a film alone, or may be mixed with other materials to form a film as a single layer. often The material may be a laminate of layers formed independently, layers formed by mixing, or layers formed by mixing layers formed independently. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and ink jet printing.

[0095] The electron injection layer of the organic EL device of the present invention can be made of alkali metal salts such as lithium fluoride and cesium fluoride, alkaline earth metal salts such as magnesium fluoride, metal complexes of quinolinol derivatives such as lithium quinolinol, metal oxides such as aluminum oxide, or metals such as ytterbium (Yb), samarium (Sm), calcium (Ca), strontium (Sr), and cesium (Cs). However, in the preferred selection of the electron transport layer and the cathode, this can be omitted.

[0096] Furthermore, in the electron injection layer or electron transport layer, a material that is further doped with N metal such as cesium in addition to the material normally used for the layer can be used.

[0097] The cathode of the organic EL device of the present invention is made of an electrode material having a low work function such as aluminum, or an alloy having an even lower work function such as a magnesium-silver alloy, a magnesium-indium alloy, or an aluminum-magnesium alloy.

[0098] For the capping layer of the organic EL device of the present invention, it is preferable to use an arylamine compound having a structure in which 2 to 6 triphenylamine structures are linked in the molecule by a single bond or a divalent group not containing a heteroatom, an amine compound having a benzoazole ring structure, or an amine compound having an aromatic heterocyclic group in the molecule. These compounds may be formed into a film alone, or may be used as a single layer formed by mixing different materials together, or may be used as a laminate structure of layers formed alone, layers formed by mixing, or layers formed by mixing layers formed alone and layers formed by mixing. These materials can be formed into thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0099] Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples. [Example]

[0100] <Synthesis of bis(4-naphthalen-2-yl-phenyl)-(2',5'-diphenyl-biphenyl-4-yl)amine (Compound 1-4)> A reaction vessel was charged with 10.0 g of bis(4-naphthalen-2-yl-phenyl)amine, 11.0 g of 4-bromo-2',5'-diphenyl-biphenyl, 0.1 g of palladium(II) acetate, 0.2 g of tri(tert-butyl)phosphine, and 2.7 g of sodium tert-butoxide, and the mixture was refluxed and stirred in toluene for 3 hours. After cooling, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 9.0 g (yield: 52.3%) of a white powder of bis(4-naphthalen-2-yl-phenyl)-(2',5'-diphenyl-biphenyl-4-yl)-amine (Compound 1-4).

[0101] [ka] (Compound 1-4)

[0102] The obtained white powder was 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.06(2H), 7.92(6H), 7.78(4H), 7.73(1H), 7.68(5H), 7.53(7H), 7.42(1H), 7.39-7.23(9H), 7.14(4H) 。 [Example]

[0103] Synthesis of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-1-yl-phenyl)-phenanthren-9-yl-amine (Compound 1-58) A reaction vessel was charged with 8.5 g of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-1-yl-phenyl)amine, 4.8 g of 9-bromo-phenanthrene, 0.1 g of palladium(II) acetate, 0.3 g of tri(tert-butyl)phosphine, and 2.3 g of sodium tert-butoxide, and the mixture was refluxed and stirred in toluene for 3 hours. After cooling, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 8.3 g (73.1% yield) of a white powder of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-1-yl-phenyl)-phenanthren-9-yl-amine (Compound 1-58).

[0104] [ka] (Compound 1-58)

[0105] The obtained white powder was 1 The following 37 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.79(1H), 8.75(1H), 8.14(1H), 8.03(1H), 7.92(1H), 7.85(2H), 7.72(6H ), 7.65(2H), 7.60(1H), 7.50(7H), 7.42(1H), 7.36(3H), 7.27-7.18(6H), 7.09(4H) 。 [Example]

[0106] Synthesis of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)-phenanthren-9-yl-amine (Compound 1-59) A reaction vessel was charged with 8.0 g of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)amine, 4.5 g of 9-bromo-phenanthrene, 0.1 g of palladium(II) acetate, 0.2 g of tri(tert-butyl)phosphine, and 2.2 g of sodium tert-butoxide, and the mixture was refluxed and stirred in toluene for 3 hours. After cooling, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 6.6 g (yield: 61.7%) of a pale yellow powder of (2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)-phenanthren-9-yl-amine (Compound 1-59).

[0107] [ka] (Compound 1-59)

[0108] The obtained pale yellow powder was 1 The following 37 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.79(1H), 8.74(1H), 8.09(1H), 8.01(1H), 7.86(4H), 7.75(1H), 7.71(5H ), 7.66(2H), 7.60(3H), 7.50(5H), 7.39(1H), 7.34-7.23(6H), 7.20(2H), 7.07(4H) 。 [Example]

[0109] Synthesis of (2'',5''-diphenyl-[1,1':4',1'']terphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)-phenylamine (Compound 1-69) A reaction vessel was charged with 6.0 g of (4-naphthalen-2-yl-phenyl)-phenylamine, 10.3 g of 4-bromo-2'',5''-[1,1':4',1'']terphenyl, 0.1 g of palladium(II) acetate, 0.2 g of tri(tert-butyl)phosphine, and 2.3 g of sodium tert-butoxide, and the mixture was refluxed overnight in toluene. After cooling, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The crude product was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / n-heptane) to obtain 7.1 g (yield: 51.7%) of a white powder of (2'',5''-diphenyl-[1,1':4',1'']terphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)-phenylamine (Compound 1-69).

[0110] [ka] (Compound 1-69)

[0111] The obtained white powder was 1 The following 37 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.04(1H), 7.91(3H), 7.73(5H), 7.66(2H), 7.56(2H), 7.51(7H), 7.42(1H), 7.39-7.18(15H), 7.10(1H) 。 [Example]

[0112] Synthesis of (2'',5''-diphenyl-[1,1':4',1'']terphenyl-4-yl)-(4-phenanthren-9-yl-phenyl)-phenylamine (Compound 1-83) In a reaction vessel, 11.0 g of (4-phenanthren-9-yl-phenyl)-phenylamine, 4-bromo-2'',5''- Diphenyl-16.2 g of [1,1':4',1'']terphenyl, 0.1 g of palladium(II) acetate, 0.3 g of tri(tert-butyl)phosphine, and 3.7 g of sodium tert-butoxide were added and stirred under reflux overnight in toluene. After cooling, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The crude product was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / n-heptane) to obtain 11.2 g (yield: 48.5%) of a white powder of (2'',5''-diphenyl-[1,1':4',1'']terphenyl-4-yl)-(4-phenanthren-9-yl-phenyl)-phenylamine (Compound 1-83).

[0113] [ka] (Compound 1-83)

[0114] The obtained white powder was 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.81(1H), 8.75(1H), 8.09(1H), 7.93(1H), 7.71(7H), 7.65-7.44(10H), 7.44-7.22(17H), 7.11(1H) 。 [Example]

[0115] Synthesis of (2',5'-diphenyl-biphenyl-4-yl)-(4'-naphthalen-1-yl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)amine (Compound 1-108) A reaction vessel was charged with 11.0 g of 4-bromophenyl-(2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)amine, 4.8 g of 4-naphthalen-1-yl-phenylboronic acid, 0.4 g of tetrakis(triphenylphosphine)palladium(0), and 4.5 g of potassium carbonate. The mixture was refluxed overnight in a toluene / ethanol / HO mixture. After cooling, methanol was added, and the precipitated crude product was filtered. The crude product was purified by crystallization using a toluene / acetone mixture to yield 11.0 g (84.6% yield) of a white powder of (2',5'-diphenyl-biphenyl-4-yl)-(4'-naphthalen-1-yl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)amine (Compound 1-108).

[0116] [ka] (Compound 1-108)

[0117] The obtained white powder was 1 The following 43 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.04(1H), 7.99(1H), 7.92(1H), 7.90(1H), 7.87(3H), 7.76(1H), 7.74-7.69(5H), 7.6 5(3H), 7.61(2H), 7.57(2H), 7.54(1H), 7.53-7.42(8H), 7.38(1H), 7.34-7.21(9H), 7.11(4H) 。 [Example]

[0118] Synthesis of (2',5'-diphenyl-biphenyl-4-yl)-(3'-naphthalen-2-yl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)amine (Compound 1-112) A reaction vessel was charged with 12.0 g of 4-bromophenyl-(2',5'-diphenyl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)amine, 5.3 g of 3-naphthalen-2-yl-phenylboronic acid, 0.4 g of tetrakis(triphenylphosphine)palladium(0), and 4.9 g of potassium carbonate. The mixture was refluxed overnight in a toluene / ethanol / HO mixture. After cooling, methanol was added, and the precipitated crude product was filtered. The crude product was purified by crystallization using a toluene / acetone mixture to yield 11.3 g (79.7% yield) of a white powder of (2',5'-diphenyl-biphenyl-4-yl)-(3'-naphthalen-2-yl-biphenyl-4-yl)-(4-naphthalen-2-yl-phenyl)amine (Compound 1-112).

[0119] [ka] (Compound 1-112)

[0120] The obtained white powder was 1 The following 43 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.11(1H), 8.03(1H), 7.97-7.93(7H), 7.81(1H), 7.78-7.57(10H), 7.57-7.43(8H), 7.37(1H), 7.33-7.03(14H) 。 [Example]

[0121] Synthesis of (9,9-diphenyl-9H-fluoren-2-yl)-(2'',5''-diphenyl-[1,1':4',1'']terphenyl-4-yl)-phenylamine (Compound 1-145) A reaction vessel was charged with 11.0 g of (2'',5''-diphenyl-[1,1':4',1'']terphenyl-4-yl)-phenylamine, 10.2 g of 2-bromo-9,9-diphenyl-9H-fluorene, 0.1 g of palladium(II) acetate, 0.2 g of tri(tert-butyl)phosphine, and 2.7 g of sodium tert-butoxide, and the mixture was refluxed and stirred overnight in toluene. After cooling, the mixture was filtered, and the filtrate was concentrated to obtain a crude product. The obtained crude product was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / n-heptane) to obtain 15.0 g (yield: 81.9%) of white powder of (9,9-diphenyl-9H-fluoren-2-yl)-(2'',5''-diphenyl-[1,1':4',1'']terphenyl-4-yl)-phenylamine (Compound 1-145).

[0122] [ka] (Compound 1-145)

[0123] The obtained white powder was 1 The following 43 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=7.71(2H), 7.67(3H), 7.60(1H), 7.52(1H), 7.50-7.40(6H), 7.40-7.30(3H), 7.27-7.13(21H), 7.08(4H), 7.04(1H), 7.00(1H) 。 [Example]

[0124] <Synthesis of biphenyl-4-yl-(5'-naphthalen-2-yl-[1,1':2',1'']terphenyl-4-yl)-([1,1':4',1'']terphenyl-4-yl)amine (Compound 1-174)> A reaction vessel was charged with 10.0 g of biphenyl-4-yl-(5'-naphthalen-2-yl-[1,1':2',1'']terphenyl-4-yl)amine, 6.5 g of 4-bromo-[1,1':4',1'']terphenyl, 0.1 g of palladium(II) acetate, 0.2 g of tri(tert-butyl)phosphine, and 2.2 g of sodium tert-butoxide, and the mixture was refluxed and stirred overnight in toluene. After cooling, the mixture was filtered, and the filtrate was concentrated to obtain a crude product. The obtained crude product was purified by crystallization using a mixed solvent of toluene and acetone to obtain 10.4 g (yield: 72.4%) of a white powder of biphenyl-4-yl-(5'-naphthalen-2-yl-[1,1':2',1'']terphenyl-4-yl)-([1,1':4',1'']terphenyl-4-yl)amine (compound 1-174).

[0125] [ka] (Compound 1-174)

[0126] The obtained white powder was 1 The following 41 hydrogen signals were detected by H-NMR (CDCl3), and the structure was identified. δ(ppm)=8.15(1H), 7.95(1H), 7.92(1H), 7.88(1H), 7.85(2H), 7.78(1H), 7.67(4H), 7.64(2H), 7.60(1H), 7 .57(3H), 7.55-7.48(5H), 7.45(2H), 7.43(2H), 7.36(1H), 7.34-7.26(6H), 7.20(4H), 7.15(2H), 7.07(2H) 。 [Example]

[0127] <Synthesis of compound (3-1-11)> A reaction vessel was charged with 45.0 g of 1-bromobenzene (D-substituted), 58.0 g of 4-tert-butylaniline, 1.0 g of palladium (II) acetate, and tert- Butoxy30.0 g of sodium, 2.0 g of bis(diphenylphosphino)-1,1'-binaphthyl, and 450 mL of toluene were added, and the mixture was refluxed and stirred for 24 hours. After cooling, the mixture was concentrated and purified by column chromatography to obtain 49.9 g (78% yield) of the following compound (3-1-11a) powder.

[0128] [ka] (3-1-11a)

[0129] A reaction vessel was charged with 20.0 g of the above compound (3-1-11a), 18.4 g of the following compound (3-1-11b), 0.5 g of palladium (II) acetate, and tert- Butoxy 18.9 g of sodium, 0.8 g of tri(tert-butyl)phosphine, and 200 mL of toluene were added, and the mixture was refluxed and stirred for 24 hours. After cooling, the mixture was concentrated and purified by column chromatography to obtain 21.5 g (yield 84%) of the following compound (3-1-11c) as a powder.

[0130] [ka] (3-1-11b)

[0131] [ka] (3-1-11c)

[0132] The above compound (3-1-11c): 12.0 g and 120 mL of tert-butylbenzene were added to a reaction vessel, and 42.5 mL of n-butyllithium was added dropwise at −78° C., followed by stirring at 60° C. for 3 hours. deathNitrogen gas was passed through the mixture while stirring. Next, 11.3 g of boron tribromide was added dropwise at -78°C, followed by stirring at room temperature for 1 hour. 5.9 g of N,N-diisopropylethylamine was added dropwise at 0°C, followed by stirring at 120°C for 2 hours. After cooling, an aqueous sodium acetate solution was added and the mixture was stirred, extracted with ethyl acetate, and the organic layer was concentrated and then purified by column chromatography to obtain 1.7 g (yield 11%) of the following compound (3-1-11) powder.

[0133] [ka] (3-1-11) [Example]

[0134] The glass transition temperature (Tg) of the triarylamine compound represented by general formula (1) was measured using a high-sensitivity differential scanning calorimeter (DSC3100SA, manufactured by Bruker AXS). The measurement results are shown below. Glass transition temperature (Tg) Compound of Example 1 107.1°C Compound of Example 2 131.2°C Compound of Example 3 129.7°C Compound of Example 4 110.0°C Compound of Example 5 127.9°C Compound of Example 6 121.4°C Compound of Example 7 109.5°C Compound of Example 8 136.2°C Compound of Example 9 116.1°C

[0135] The triarylamine compound represented by the general formula (1) has a glass transition point (Tg) of 100° C. or higher, which indicates that the thin film state is stable. [Example]

[0136] A 100 nm thick film was formed by vapor deposition on an ITO substrate using the triarylamine compound represented by general formula (1), and the work function was measured using an ionization potential measurement device (PYS-202, manufactured by Sumitomo Heavy Industries, Ltd.). The measurement results are shown below. Work function Compound of Example 1 5.67 eV Compound of Example 2 5.72 eV Compound of Example 3 5.75 eV Compound of Example 4 5.72 eV Compound of Example 5 5.76 eV Compound of Example 6 5.69 eV Compound of Example 7 5.69 eV Compound of Example 8 5.68 eV Compound of Example 9 5.69 eV

[0137] The triarylamine compounds represented by general formula (1) exhibit a favorable energy level compared to the work function of 5.4 eV of common hole transport materials such as NPD and TPD, and are found to have good hole transport ability and excellent electron blocking ability. [Example]

[0138] As shown in Figure 21, the organic EL device was fabricated by depositing a hole injection layer 3, a first hole transport layer 4, a second hole transport layer 5, an emitting layer 6, an electron transport layer 7, an electron injection layer 8, a cathode 9, and a capping layer 10 in this order on a glass substrate 1 on which a reflective ITO electrode had previously been formed as a transparent anode 2.

[0139] Specifically, a 50 nm thick ITO film, a 100 nm thick silver alloy reflective film, and a 5 nm thick ITO film were sequentially formed on a glass substrate 1 as a transparent anode 2. The film was then subjected to ultrasonic cleaning in isopropyl alcohol for 20 minutes and then dried on a hot plate heated to 250°C for 10 minutes. After 15 minutes of UV ozone treatment, the ITO-attached glass substrate was placed in a vacuum deposition machine and the pressure was reduced to 0.001 Pa or less. Next, a hole injection layer 3 was formed covering the transparent anode 2 by binary deposition of an electron acceptor (Acceptor-1) of the following structural formula and a compound (HTM-1) of the following structural formula at a deposition rate ratio of Acceptor-1:Compound (HTM-1) = 3:97, resulting in a thickness of 10 nm. On top of this hole injection layer 3, a first hole transport layer 4 was formed of a compound (HTM-1) of the following structural formula to a thickness of 140 nm. On the first hole transport layer 4, the compound (1-4) of Example 1 was formed as a second hole transport layer 5 to a thickness of 5 nm. 10 Compound (3-1-11) of the formula shown below and compound (EMH-1) of the formula shown below were binary-evaporated at a vapor deposition rate ratio of compound (3-1-11):compound (EMH-1) = 5:95 to form a film thickness of 20 nm. On this light-emitting layer 6, compound (ETM-1) of the formula shown below and compound (ETM-2) of the formula shown below were binary-evaporated at a vapor deposition rate ratio of compound (ETM-1):compound (ETM-2) = 50:50 to form an electron-transporting layer 7 to form a film thickness of 30 nm. On this electron-transporting layer 7, lithium fluoride was formed as electron-injecting layer 8 to a film thickness of 1 nm. On this electron-injecting layer 8, magnesium-silver alloy was formed as cathode 9 to a film thickness of 12 nm. Finally, compound (CPL-1) of the formula shown below was formed as capping layer 10 to a film thickness of 60 nm. A DC voltage was applied to the fabricated organic EL device in the atmosphere at room temperature. When The luminescence characteristics were measured, and the results are summarized in Table 1.

[0140] [ka] (Acceptor-1)

[0141]

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[0142]

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[0143]

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[0144]

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[0145]

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[0146]

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[0147]

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Example

[0148] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-58) of Example 2 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the air at room temperature. The results are summarized in Table 1.

[0149] [ka] Compound (1-58) [Example]

[0150] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-59) of Example 3 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0151] [ka] Compound (1-59) [Example]

[0152] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-69) of Example 4 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0153] [ka] Compound (1-69) [Example]

[0154] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-83) of Example 5 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0155] [ka] Compound (1-83) [Example]

[0156] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-108) of Example 6 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0157] [ka] Compound (1-108) [Example]

[0158] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-112) of Example 7 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0159] [ka] Compound (1-112) [Example]

[0160] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-145) of Example 8 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0161] [ka] Compound (1-145) [Example]

[0162] An organic EL device was fabricated under the same conditions as in Example 13, except that compound (1-174) of Example 9 was used instead of compound (1-4) of Example 1 as the material for the second hole transport layer 5. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0163] [ka] Compound (1-174)

[0164] [Comparative Example 1] For comparison, an organic EL device was fabricated under the same conditions as in Example 13, except that the compound (HTM-2) of the following structural formula was used as the material for the second hole transport layer 5 instead of the compound (1-4) in Example 1. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0165] [ka] (HTM-2)

[0166] Comparative Example 2 For comparison, an organic EL device was fabricated under the same conditions as in Example 13, except that the compound (HTM-3) of the following structural formula was used as the material for the second hole transport layer 5 instead of the compound (1-4) in Example 1. The light-emitting characteristics of the fabricated organic EL device were measured when a DC voltage was applied in the atmosphere at room temperature. The results are summarized in Table 1.

[0167] [ka] (HTM-3)

[0168] The device life was measured using the organic EL devices fabricated in the examples and comparative examples. The results are summarized in Table 1. The device life was measured when the luminance at the start of light emission (initial luminance) was 2000 cd / m 2 When driven at a constant current, the luminance was 1900 cd / m 2 (corresponding to 95% of the initial brightness of 100%: 95% decay)

[0169] [Table 1]

[0170] As shown in Table 1, the current density was 10 mA / cm 2 The luminous efficiency when a current of 100 kJ / A was passed was 7.42 to 8.97 cd / A in Comparative Examples 1 and 2, and was clearly higher in Examples 13 to 21 at 9.57 to 10.52 cd / A. Furthermore, the power efficiency was also clearly higher at 8.83 to 9.75 lm / W in Examples 13 to 21, and was clearly higher in Examples 13 to 21, and was 6.75 to 8.19 lm / W in Comparative Examples 1 and 2. Furthermore, it can be seen that the element lifetime (95% decay) was 223 to 245 hours in Comparative Examples 1 and 2, and was 303 to 645 hours in Examples 13 to 21, which was significantly longer.

[0171] As is clear from the above results, the triarylamine compound having a specific structure represented by general formula (1) has a higher hole mobility and an excellent electron blocking ability compared to the conventional triarylamine compound used in the comparative example element. Therefore, it is understood that an organic EL element using the triarylamine compound together with the material used in the light-emitting layer of the present invention can realize an organic EL element having a higher luminous efficiency and a longer lifetime compared to the conventional organic EL element. [Industrial Applicability]

[0172] The organic EL device using the triarylamine compound having a specific structure of the present invention has improved luminous efficiency and durability compared to conventional organic EL devices, and therefore can be applied to, for example, home appliances and lighting.

[0173] 1. Glass substrate 2 transparent anode 3. Hole injection layer 4 First hole transport layer 5 Second hole transport layer 6. Light-emitting layer 7 Electron transport layer 8 Electron injection layer 9 Cathode 10 Capping Layer

Claims

1. An organic electroluminescence device having at least a first hole transport layer, a second hole transport layer, a blue light-emitting layer, and an electron transport layer, arranged in this order from the anode side, between an anode and a cathode, wherein at least one layer of the second hole transport layer or a laminate film arranged between the first hole transport layer and the electron transport layer contains a triarylamine compound represented by the following general formula (1), and the blue light-emitting layer contains a compound represented by the following general formula (3-1) or (3-2) as a blue light-emitting dopant: 【Chemistry 1】 （１） (In the formula, A is a monovalent group having the dashed line portion shown in the following general formula (2-2) as a bonding site, and B and C may be the same or different and represent a monovalent group having the dashed line portion shown in the following general formula (2-2) as a bonding site, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted condensed polycyclic aromatic group. However, B and C are not simultaneously monovalent groups shown in the following general formula (2-2).) 【Chemistry 2】 （２－２） (In the formula, the dashed line represents a bonding site. R represents a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, an optionally substituted linear or branched alkyl group of 1 to 6 carbon atoms, an optionally substituted cycloalkyl group of 5 to 10 carbon atoms, an optionally substituted linear or branched alkenyl group of 2 to 6 carbon atoms, an optionally substituted linear or branched alkyloxy group of 1 to 6 carbon atoms, an optionally substituted cycloalkyloxy group of 5 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or un ... cycloalkyloxy group of 5 to 10 carbon atoms, a substituted or unsubstituted cycloalkyloxy group of 5 to 10 carbon atoms, a substituted or unsubstituted cycloalkyloxy group of 5 to 10 carbon atoms, a substituted or unsubstituted cycloalkyloxy group of 5 to 10 carbon atoms, a substituted or unsubstituted cycloalkyloxy group represents a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group. n is the number of R and represents an integer of 0 to 3. When n is 2 or 3, multiple Rs bonded to the same benzene ring may be the same or different, and may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring. L represents a divalent group of a substituted or unsubstituted aromatic hydrocarbon, or a divalent group of a substituted or unsubstituted fused polycyclic aromatic. m represents an integer of 1 to 3. When m is 2 or 3, Ls may be the same or different. Ar １ , Ar ２ may be the same or different and represent a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group. 【Transformation 3】 （３－１） 【Chemistry 4】 （３－２） (In the general formula (3-1) and the general formula (3-2), Q １ ~Q ３ may be the same or different, and represent substituted or unsubstituted benzene, substituted or unsubstituted naphthalene, substituted or unsubstituted anthracene, substituted or unsubstituted fluorene, substituted or unsubstituted phenanthrene, substituted or unsubstituted pyridine, substituted or unsubstituted pyrimidine, substituted or unsubstituted triazine, substituted or unsubstituted pyrrole, substituted or unsubstituted quinoline, substituted or unsubstituted isoquinoline, substituted or unsubstituted indene, substituted or unsubstituted indole, substituted or unsubstituted indoline, substituted or unsubstituted carbazole, substituted or unsubstituted carboline, substituted or unsubstituted benzoxazole, substituted or unsubstituted benzothiazole, substituted or unsubstituted quinoxaline, substituted or unsubstituted benzimidazole, substituted or unsubstituted pyrazole, substituted or unsubstituted dibenzofuran, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted naphthyridine, substituted or unsubstituted phenanthroline, or substituted or unsubstituted acridine. X represents B, P, P=O, or P=S. Y １ ~Y ３ may be the same or different, and N-R ４ , C.R. ５ R ６ , O, S, Se or SiR ７ R ８ and R ４ ~R ８ may be the same or different, and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group of 1 to 6 carbon atoms which may have a substituent, a cycloalkyl group of 5 to 10 carbon atoms which may have a substituent, a linear or branched alkenyl group of 2 to 6 carbon atoms which may have a substituent, a linear or branched alkyloxy group of 1 to 6 carbon atoms which may have a substituent, a cycloalkyloxy group of 5 to 10 carbon atoms which may have a substituent, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted aryloxy group. ５ and R ６ , R ７ and R ８ The groups may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom, or a sulfur atom to form a ring. １ ~Y ３ N-R ４ , C.R. ５ R ６ , or SiR ７ R ８ In the case of ４ ~R ８ are the adjacent Q １ , Q ２ or Q ３ and may be bonded to each other via a linking group such as a substituted or unsubstituted methylene group, an oxygen atom, a sulfur atom, or a monosubstituted amino group to form a ring.)

2. 2. The organic electroluminescence device according to claim 1, wherein the general formula (2-2) is a monovalent group represented by the following general formula (2-3): 【Transformation 5】 （２－３） (In the formula, the dashed line represents the bonding site, and Ar １ , Ar ２ , n and R are as defined in the general formula (2-2). p represents 0 or 1.

3. 2. The organic electroluminescence device according to claim 1, wherein the general formula (2-2) is a monovalent group represented by the following general formula (2-4): 【Transformation 6】 （２－４） (In the formula, the dashed line represents the bonding site, and Ar １ , Ar ２ is as defined in the general formula (2-2). p represents 0 or 1.

4. 4. The organic electroluminescence device according to claim 1, wherein the blue light-emitting layer contains an anthracene derivative having an anthracene skeleton in the molecule.

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