Arylamine compound, organic electroluminescent element, and electronic device

Abstract

The purpose of the present invention is: to provide an organic compound that is for use as a material for a highly efficient and durable organic EL element, that has excellent hole injection / transport performance, that has an electron-blocking ability, and that has high stability and excellent properties in a thin-film state; and to further provide a highly efficient and durable organic EL element using said compound.　The present invention is an arylamine compound represented by general formula (1) below.　In the formula, Ar1 and Ar2 represent a substituted or unsubstituted aromatic hydrocarbon group, etc., Ar3 and Ar4 represent a substituted or unsubstituted phenyl group, etc., L represents a substituted or unsubstituted divalent aromatic hydrocarbon group, etc., R1-R3 represent a hydrogen atom, etc., and n represents an integer of 1-2.

Description

[Technical Field]

[0001] The present invention relates to a compound and an element suitable for an organic electroluminescence element (hereinafter abbreviated as organic EL element), which is a self-luminous element suitable for various display devices, and more particularly to an arylamine compound and an organic EL element using the 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 therefore active research has been conducted on them.

[0003] In 1987, C.W. Tang and his colleagues at Eastman Kodak Company developed a layered structure element in which various roles were assigned to each material, making organic EL devices practical. They layered a phosphor capable of transporting electrons and an organic material capable of transporting holes, and injected both charges into the phosphor layer to emit light, achieving an luminance of 1000 cd / m at a voltage of 10 V or less. 2 Such high brightness has been achieved (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). Furthermore, devices that utilize luminescence due to thermally activated delayed fluorescence (TADF) have also been developed, and in 2011, Adachi et al. of Kyushu University achieved an external quantum efficiency of 5.3% using a device that uses a thermally activated delayed fluorescence material (see, for example, 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 aforementioned non-patent document, the selection of organic materials in an organic EL device has a significant impact on various properties of the device, such as efficiency and durability (see, for example, non-patent document 2).

[0007] In organic EL devices, charges injected from both electrodes recombine in the light-emitting layer to emit light. However, the efficient transfer of both hole and electron charges to the light-emitting layer is crucial, making it necessary to achieve a device with excellent carrier balance. Therefore, by using a material that has the properties of enhancing hole injection properties (supplying holes injected from the anode to the light-emitting layer) and enhancing electron blocking properties (blocking electrons injected from the cathode), the probability of holes and electrons recombining in the light-emitting layer can be improved, and by confining excitons generated in the light-emitting layer, high luminous efficiency can be achieved. To achieve this, the role played by 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] Hole transport materials that have been used in organic EL devices to date include N,N'-diphenyl-N,N'-di(α-naphthyl)benzidine (NPD) and various aromatic amine derivatives (see, for example, Patent Document 1 and Patent Document 2). However, although NPD has good hole transport capabilities, its glass transition temperature (Tg), which is an indicator of heat resistance, is as low as 96°C, and crystallization occurs under high-temperature conditions, causing a deterioration in device characteristics (see, for example, Non-Patent Document 4).

[0010] In addition, among the aromatic amine derivatives described in the above patent documents, the hole mobility is 10 -3 cm 2 Although there are compounds with excellent mobility of 1 / Vs or more (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 achieve even higher efficiency, materials with better electron blocking properties, more stable thin films, and higher 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.

[0011] In order to solve this problem, arylamine compounds having a substituted carbazole structure or a triarylbenzene structure have been proposed as compounds with improved properties such as heat resistance and hole injection properties (see, for example, Patent Documents 4 and 5). However, although the device life and luminous efficiency have been improved in devices using these compounds in the hole injection layer or hole transport layer, they are still not sufficient, and there is a demand for further reduction in driving voltage, improvement in luminous efficiency, and extension of the device life. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] U.S. Patent No. 5,792,557 [Patent Document 2] U.S. Patent No. 5,639,914 [Patent Document 3] U.S. Patent No. 7,759,030 [Patent Document 4] U.S. Patent No. 8,021,764 [Patent Document 5] U.S. Patent No. 10,818,844 [Patent Document 6] European Patent No. 2684932 [Non-patent literature]

[0013] [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

[0014] The object of the present invention is to provide a material for highly efficient and durable organic EL devices, which has (1) excellent hole injection and transport properties, (2) electron blocking ability, (3) high stability in a thin film state, and (4) excellent durability. Furthermore, by using the above material, it is possible to provide an organic EL device that (1) has high luminous efficiency and power efficiency, (2) has low luminous initiation voltage and practical driving voltage, and (3) has a long life.

[0015] To achieve the above object, the present inventors focused on the advantages of arylamine compounds having a triarylphenyl structure, such as excellent hole injection / transport capability, electron blocking capability, and thin film stability and durability, and discovered that by optimizing the structure by introducing substituents at specific positions, the properties of the material can be dramatically improved. The use of this material in organic EL devices improves luminous efficiency and power efficiency, enables suppression of light-emission onset voltage and practical driving voltage, and realizes a longer lifespan than conventional devices, thereby completing the present invention.

[0016] 1) That is, the present invention is an arylamine compound represented by the following general formula (1):

[0017] [ka] In the formula, Ar1 and Ar2 may be the same or different and each represent a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted fused polycyclic aromatic group; Ar3 and Ar4 may be the same or different and represent a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylsilyl group, a substituted or unsubstituted carbazolyl group, or a substituted or unsubstituted phenanthrenyl group; L represents a substituted or unsubstituted divalent aromatic hydrocarbon group, a substituted or unsubstituted divalent aromatic heterocyclic group, or a substituted or unsubstituted divalent condensed polycyclic aromatic group; R1 to R3 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 aromatic heterocyclic group, a substituted or unsubstituted fused polycyclic aromatic group, or a substituted or unsubstituted aryloxy group; n represents an integer of 1 to 2, and when n is 2, L's may be the same or different.

[0018] 2) The present invention also relates to the arylamine compound according to the above item 1), wherein R1 to R3 in the general formula (1) may be the same or different and each represent a hydrogen atom or a deuterium atom.

[0019] 3) The present invention also relates to the arylamine compound according to 1) or 2) above, wherein at least one of Ar3 and Ar4 in general formula (1) is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted carbazolyl group.

[0020] 4) The present invention also relates to the arylamine compound according to any one of the above 1) to 3), wherein Ar4 in the general formula (1) is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted carbazolyl group.

[0021] 5) The present invention also relates to the arylamine compound according to any one of the above 1) to 4), wherein L in the general formula (1) is an unsubstituted phenylene group, an unsubstituted biphenylene group, or an unsubstituted naphthylene group.

[0022] 6) The present invention also relates to the arylamine compound according to any one of the above 1) to 5), wherein Ar1 and Ar2 in general formula (1) may be the same or different and are a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted phenanthrenyl group, a substituted or unsubstituted triphenylsilyl group, a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, or a substituted or unsubstituted dibenzothienyl group.

[0023] 7) The present invention also relates to the arylamine compound according to any one of the above 1) to 6), wherein n in the general formula (1) is 1.

[0024] 8) The present invention also provides an organic EL device having a pair of electrodes and at least one organic layer sandwiched between them, wherein the organic layer contains the arylamine compound described in any one of 1) to 7) above.

[0025] 9) The present invention also relates to the organic EL device according to the above 8), wherein the organic layer is a hole transport layer.

[0026] 10) The present invention also relates to the organic EL device according to the above item 8), wherein the organic layer is an electron blocking layer.

[0027] 11) The present invention also relates to the organic EL device according to the above item 8), wherein the organic layer is a hole injection layer.

[0028] 12) The present invention also relates to the organic EL device according to the above item 8), wherein the organic layer is a light-emitting layer.

[0029] 13) The present invention also relates to an electronic device including an element having a pair of electrodes and at least one organic layer sandwiched between them, wherein the organic layer contains the arylamine compound described in any one of 1) to 6) above.

[0030] 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 to Ar4 in general formula (1), examples of the "aromatic hydrocarbon group", "aromatic heterocyclic group" or "fused polycyclic aromatic group" include a phenyl group, a biphenyl group, a terphenyl 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 triazinyl group, a furyl group, a pyrrolidinyl group, a pyrid ... Examples of the alkyl group include an alkyl group, an alkyl group, an alkyl aryl group, an alkyl thienyl group, an alkyl quinolyl group, an isoquinolyl group, an alkyl benzofuranyl group, an alkyl benzothienyl group, an indolyl group, a carbazolyl group, an alkyl benzoxazolyl group, an alkyl benzothiazolyl group, an alkyl azafluorenyl group, an alkyl diazafluorenyl group, an alkyl azaspirobifluorenyl group, an alkyl diazaspirobifluorenyl group, an alkyl quinoxalinyl group, an alkyl benzimidazolyl group, an alkyl pyrazolyl group, an alkyl dibenzofuranyl group, an alkyl dibenzothienyl group, an alkyl naphthyridinyl group, an alkyl phenanthrolinyl group, an alkyl acridinyl group, an alkyl carbolinyl group, an alkyl aryl group having 6 to 30 carbon atoms, and an alkyl heteroaryl group having 2 to 20 carbon atoms.

[0031] Examples of the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by Ar1 to Ar4 in general formula (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; an arylalkyloxy group such as a benzyloxy group or a phenethyloxy group; Examples of such groups include a silyl group; aromatic hydrocarbon groups or condensed polycyclic aromatic groups such as a phenyl group, a biphenyl group, a terphenyl 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. In addition, benzene rings substituted with these substituents, or multiple substituents substituted on the same benzene ring, 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.

[0032] Examples of the "divalent aromatic hydrocarbon group," "divalent aromatic heterocyclic group," or "divalent fused polycyclic aromatic group" in the "substituted or unsubstituted divalent aromatic hydrocarbon group," "substituted or unsubstituted divalent aromatic heterocyclic group," or "substituted or unsubstituted divalent fused polycyclic aromatic group" represented by L in general formula (1) include groups in which one hydrogen atom has been removed from the group shown 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 Ar1 to Ar4 in general formula (1).

[0033] Examples of the "substituent" in the "substituted or unsubstituted divalent aromatic hydrocarbon group," "substituted or unsubstituted divalent aromatic heterocyclic group," or "substituted or unsubstituted divalent fused polycyclic aromatic group" represented by L in general formula (1) include the same as those shown as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by Ar1 to Ar4 in general formula (1), and possible embodiments thereof are also similar.

[0034] In the "linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent," "cycloalkyl group having 5 to 10 carbon atoms which may have a substituent," or "linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent," represented by R1 to R3 in general formula (1), examples of the "linear or branched alkyl group having 1 to 6 carbon atoms," "cycloalkyl group having 5 to 10 carbon atoms," or "linear or branched alkenyl group having 2 to 6 carbon atoms" include, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an ethyl ... Examples of the substituent include an alkyl 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. Benzene rings substituted with these substituents, or multiple substituents substituted on the same benzene ring, 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.

[0035] Examples of the "substituent" in the "optionally substituted linear or branched alkyl group of 1 to 6 carbon atoms," "optionally substituted cycloalkyl group of 5 to 10 carbon atoms," or "optionally substituted linear or branched alkenyl group of 2 to 6 carbon atoms" represented by R1 to R3 in general formula (1) include the same as those shown as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by Ar1 to Ar4 in general formula (1), and possible embodiments thereof are also similar.

[0036] In 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, which may have a substituent," represented by R1 to R3 in general formula (1), examples of the "linear or branched alkyloxy group having 1 to 6 carbon atoms" or "cycloalkyloxy group having 5 to 10 carbon atoms" 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. Benzene rings substituted with these substituents, or multiple substituents substituted on the same benzene ring, 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.

[0037] Examples of the "substituent" in the "linear or branched alkyloxy group having 1 to 6 carbon atoms, which may have a substituent," or the "cycloalkyloxy group having 5 to 10 carbon atoms, which may have a substituent," represented by R1 to R3 in general formula (1) include the same as those shown as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group," which are represented by Ar1 to Ar4 in general formula (1), and possible embodiments thereof are also similar.

[0038] 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 R1 to R3 in general formula (1) include the same as those given 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 Ar1 to Ar4 in general formula (1).

[0039] Examples of the "substituent" in the "substituted or unsubstituted aromatic hydrocarbon group," "substituted or unsubstituted aromatic heterocyclic group," or "substituted or unsubstituted fused polycyclic aromatic group" represented by R1 to R3 in general formula (1) include the same as those shown as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by Ar1 to Ar4 in general formula (1), and possible embodiments thereof are also similar.

[0040] Examples of the "aryloxy group" in the "substituted or unsubstituted aryloxy group" represented by R1 to R3 in general formula (1) include a phenyloxy group, a biphenylyloxy group, a terphenylyloxy group, a naphthyloxy group, an anthracenyloxy group, a phenanthrenyloxy group, a fluorenyloxy group, a spirobifluorenyloxy group, an indenyloxy group, a pyrenyloxy group, a perylenyloxy group, a fluoranthenyloxy group, a triphenylenyloxy group, a benzofuranyloxy group, a benzothienyloxy group, an indolyloxy group, a carbazolyloxy group, a dibenzofuranyloxy group, and a dibenzothienyloxy group, as well as an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms. Benzene rings substituted with these substituents, or multiple substituents substituted on the same benzene ring, 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.

[0041] Examples of the "substituent" in the "substituted or unsubstituted aryloxy group" represented by R1 to R3 in general formula (1) include the same as those shown as the "substituent" in the "substituted aromatic hydrocarbon group," "substituted aromatic heterocyclic group," or "substituted fused polycyclic aromatic group" represented by Ar1 to Ar4 in general formula (1), and possible embodiments thereof are also similar.

[0042] At least one of Ar3 and Ar4 in general formula (1) is preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted carbazolyl group, and more preferably an unsubstituted phenyl group, an unsubstituted biphenyl group, or an unsubstituted carbazolyl group.

[0043] In general formula (1), Ar3 and Ar4 may be the same or different and are preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted naphthyl group because they have excellent electron blocking ability, more preferably an unsubstituted phenyl group, an unsubstituted biphenyl group, or an unsubstituted naphthyl group, and particularly preferably an unsubstituted phenyl group or an unsubstituted naphthyl group.

[0044] In general formula (1), L is preferably an unsubstituted phenylene group, an unsubstituted biphenylene group, or an unsubstituted naphthylene group because of its excellent electron blocking ability, and more preferably an unsubstituted phenylene group or an unsubstituted biphenylene group. In addition, n in general formula (1) is preferably 1.

[0045] In general formula (1), Ar1 and Ar2 may be the same or different and are preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, or a substituted or unsubstituted terphenyl group, because these groups have excellent electron blocking ability, and are more preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group.

[0046] R1 to R3 in general formula (1) may be the same or different and are preferably hydrogen atoms or deuterium atoms, more preferably hydrogen atoms for ease of synthesis.

[0047] The arylamine compound represented by the general formula (1) and suitably used in the organic EL device of the present invention is preferably used as a constituent material of the hole injection layer, hole transport layer, electron blocking layer, or light-emitting layer of the organic EL device, and more preferably as a constituent material of the hole transport layer or electron blocking layer.

[0048] The arylamine compounds of the present invention have the following properties compared to conventional materials: (1) better hole injection properties, (2) higher hole mobility, (3) superior electron blocking ability, (4) higher electron resistance, (5) stable existence in a thin film state, and (6) superior heat resistance. By using the arylamine compounds of the present invention in organic EL devices, properties such as (7) higher luminous efficiency, (8) lower luminous initiation voltage, (9) lower practical driving voltage, and (10) longer life can be obtained.

[0049] The arylamine compound of the present invention has excellent hole injection / transport properties, thin film stability, and durability. As a result, an organic EL device having a hole injection layer and / or hole transport layer prepared using the compound as a hole injection material and / or hole transport material has improved hole transport efficiency to the light-emitting layer, thereby improving luminous efficiency, and can also improve durability of the device by reducing the driving voltage, thereby achieving high efficiency, low driving voltage, and long life.

[0050] The arylamine compound of the present invention has excellent electron blocking ability, high electron resistance, and is stable even in a thin film state, and is characterized by its ability to confine excitons generated in the light-emitting layer. As a result, organic EL devices having an electron-blocking layer prepared using the compound as an electron-blocking material have high luminous efficiency due to an improved probability of hole-electron recombination and suppression of thermal deactivation, and also have improved maximum luminance due to a reduced driving voltage and improved current resistance.

[0051] The arylamine compound of the present invention has excellent hole-transporting properties and a wide band gap. As a result, an organic EL device having an emitting layer fabricated using the compound as a host material can have a reduced driving voltage and improved luminous efficiency by forming the emitting layer by supporting a fluorescent emitter, a phosphorescent emitter, or a delayed fluorescent emitter, which are called dopants.

[0052] Therefore, the arylamine compound of the present invention is useful as a material for a hole injection layer, a hole transport layer, an electron blocking layer, or an emitting layer of an organic EL device, and can improve the luminous efficiency, driving voltage, and durability of conventional organic EL devices.

[0053] Additionally, the arylamine compound of the present invention can be used not only in organic EL devices but also in the field of electronic devices such as electrophotographic photoreceptors, image sensors, photoelectric conversion elements, and solar cells. [Brief explanation of the drawings]

[0054] [Figure 1] FIG. 1 shows compounds (1) to (12) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 2] FIG. 1 shows compounds (13) to (24) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 3] FIG. 1 shows compounds (25) to (36) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 4] FIG. 1 shows compounds (37) to (48) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 5] FIG. 1 shows compounds (49) to (60) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 6] FIG. 1 shows compounds (61) to (75) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 7] FIG. 1 shows compounds (76) to (87) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 8] FIG. 1 shows compounds (88) to (99) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 9]FIG. 1 shows compounds (100) to (111) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 10] FIG. 1 shows compounds (112) to (123) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 11] FIG. 1 shows compounds (124) to (135) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 12] FIG. 1 shows compounds (136) to (146) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 13] FIG. 1 shows compounds (147) to (158) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 14] FIG. 1 shows compounds (159) to (170) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 15] FIG. 1 shows compounds (171) to (182) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 16] FIG. 1 shows compounds (183) to (185) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 17] FIG. 1 is a diagram showing the configurations of the organic EL devices of Examples 17 to 21 and Comparative Examples 1 and 2. DETAILED DESCRIPTION OF THE INVENTION

[0055] The arylamine compounds of the present invention are novel compounds, but these compounds can be synthesized according to methods known per se (see, for example, Patent Document 5).

[0056] Among the arylamine compounds represented by the general formula (1) that can be suitably used in the organic EL device of the present invention, specific examples of preferred compounds are shown in Figures 1 to 16, but the present invention is not limited to these compounds.

[0057] The arylamine compound represented by general formula (1) can be purified by known methods such as column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization or crystallization using a solvent, or sublimation purification. The compound can be identified by NMR analysis. Physical properties include measurements of melting point, glass transition point (Tg), and work function. The melting point is an index of vapor deposition properties, the glass transition point (Tg) is an index of stability in the thin film state, and the work function is an index of hole injection properties, hole transport properties, or electron blocking properties.

[0058] The melting point and glass transition point (Tg) can be measured, for example, by a high-sensitivity differential scanning calorimeter (manufactured by Bruker AXS, DSC3100SA) using a powder.

[0059] The work function can be determined, for example, by forming a 100 nm thin film on an ITO substrate and measuring it with an ionization potential measuring device (PYS-202, manufactured by Sumitomo Heavy Industries, Ltd.).

[0060] The organic EL device of the present invention may have a structure comprising, in order on a substrate, an anode, a hole injection layer, a hole transport layer, an emitting layer, an electron transport layer, an electron injection layer, and a cathode; an electron blocking layer between the hole transport layer and the emitting layer; or a hole blocking layer between the emitting layer and the electron transport layer. In these multilayer structures, a single organic layer may serve multiple functions. For example, a single organic layer may serve both as a hole injection layer and a hole transport layer, or as an electron injection layer and an electron transport layer. Two or more organic layers having the same function may also be stacked, such as two stacked hole transport layers, two stacked emitting layers, or two stacked electron transport layers.

[0061] For the anode of the organic EL device of the present invention, an electrode material with a large work function, such as ITO or gold, is used. Materials that can be used for the hole injection layer of the organic EL device of the present invention include porphyrin compounds typified by copper phthalocyanine, starburst triphenylamine derivatives, arylamine compounds having two or more triphenylamine structures or carbazolyl structures in the molecule, each of which is linked by a single bond or a divalent group containing no heteroatom, 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.

[0062] In addition to the arylamine compound of the present invention, materials for the hole injection layer and hole transport layer of the organic EL device of the present invention can 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[(di-4-tolylamino)phenyl]cyclohexane (TAPC), and arylamine compounds having two or more triphenylamine structures or carbazolyl structures in the molecule, each linked by a single bond or a divalent group containing no heteroatom. These materials can be used to form a film alone or in combination, and each can be used as a single layer. The layer may also be a laminate structure of layers formed from these materials alone, a laminate structure of layers formed from a mixture of these materials, or a laminate structure of layers formed from a mixture of these materials alone and layers formed from a mixture of multiple materials. Furthermore, a coating-type polymer material such as poly(3,4-ethylenedioxythiophene) (PEDOT) / poly(styrene sulfonate) (PSS) can be used as the material for the hole injection / transport layer. These materials can be formed into thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0063] For the hole injection layer and the hole transport layer, materials that are typically used for these layers can be doped with P, such as trisbromophenylaminehexachloroantimony or radialene derivatives (see, for example, Patent Document 6), or polymer compounds that have the structure of a benzidine derivative such as TPD in their partial structure.

[0064] In addition to the arylamine compound of the present invention, other compounds with electron blocking properties can be used as materials for the electron-blocking layer of the organic EL device of the present invention, 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. These materials may also serve as materials for the hole-transporting layer. These materials may be used alone or in combination to form a film, and multiple types may be used as a mixture, each of which may be used as a single layer. Furthermore, the laminated structure may be a laminated structure of layers formed from these materials alone, a laminated structure of layers formed from a mixture of these materials, or a laminated structure of layers formed from a mixture of these materials alone and a layer formed from a mixture of several kinds of these materials. These materials can be formed into thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0065] In addition to the arylamine compound of the present invention, other materials that can be used for the light-emitting layer of the organic EL device of the present invention include metal complexes of quinolinol derivatives such as tris(8-quinolinolato)aluminum (Alq3), various metal complexes, anthracene derivatives, bisstyrylbenzene derivatives, pyrene derivatives, oxazole derivatives, and polyparaphenylenevinylene derivatives. The light-emitting layer may also be composed of a host material and a dopant material. Anthracene derivatives are preferred as the host material. In addition to the light-emitting materials, such as the arylamine compound of the present invention, heterocyclic compounds having an indole ring as a fused ring substructure, heterocyclic compounds having a carbazole ring as a fused ring substructure, carbazole derivatives, thiazole derivatives, benzimidazole derivatives, and polydialkylfluorene derivatives can also be used. Furthermore, dopant materials that can be used include quinacridone, coumarin, rubrene, perylene, and their derivatives, benzopyran derivatives, rhodamine derivatives, and aminostyryl derivatives. These materials may be used alone or in combination, and each may be used as a single layer. These materials may be used in a laminated structure consisting of layers formed from a single material, a laminated structure consisting of layers formed from a mixture of materials, or a laminated structure consisting of layers formed from a single material and a mixture of materials. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0066] Phosphorescent emitters can also be used as light-emitting materials. Examples of phosphorescent emitters include metal complexes of iridium, platinum, and the like. Examples include green phosphorescent emitters such as Ir(ppy)3, blue phosphorescent emitters such as FIrpic and FIr6, and red phosphorescent emitters such as Btp2Ir(acac). In this case, examples of host materials include hole-injecting / transporting host materials such as carbazole derivatives such as 4,4'-di(N-carbazolyl)biphenyl (CBP), TCTA, and mCP, as well as the arylamine compounds of the present invention. Examples of electron-transporting host materials include p-bis(triphenylsilyl)benzene (UGH2) and 2,2',2''-(1,3,5-phenylene)-tris(1-phenyl-1H-benzimidazole) (TPBI). Using these materials allows for the fabrication of high-performance organic EL devices.

[0067] 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 to avoid concentration quenching.

[0068] Furthermore, materials that emit delayed fluorescence, such as CDCB derivatives such as PIC-TRZ, CC2TA, PXZ-TRZ, and 4CzIPN, can also be used as light-emitting materials (see, for example, Non-Patent Document 3). These materials can be formed into thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0069] Materials for the hole-blocking layer of the organic EL device of the present invention include compounds with hole-blocking properties, such as phenanthroline derivatives such as bathocuproine (BCP), metal complexes of quinolinol derivatives such as bis(2-methyl-8-quinolinolato)-4-(phenylphenolato)aluminum (BAlq), various rare earth complexes, oxazole derivatives, triazole derivatives, and triazine derivatives. These materials may also serve as materials for the electron-transporting layer. These materials may be formed into films alone or in combination, and each may be used as a single layer. Furthermore, these materials may be used in a laminated structure consisting of layers formed alone or in a mixture, or in a laminated structure consisting of layers formed alone and layers formed in a mixture. These materials can be formed into thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0070] Materials for the electron transport layer of the organic EL device of the present invention include 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, and silole derivatives. These materials can be used to form films alone or in combination, and each can be used as a single layer. Furthermore, these materials can be used in a laminated structure consisting of layers formed alone, layers formed in a mixture, or layers formed in a mixture of these materials alone and layers formed in a mixture. These materials can be used to form thin films using known methods such as vapor deposition, spin coating, and inkjet printing.

[0071] Materials that can be used for the electron injection layer of the organic EL device of the present invention include 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, and metals such as ytterbium (Yb), samarium (Sm), calcium (Ca), strontium (Sr), and cesium (Cs). The electron injection layer can be omitted by selecting the electron transport layer and the cathode appropriately.

[0072] Furthermore, for the electron injection layer and the electron transport layer, materials that are normally used for these layers and are doped with N-type metals such as cesium can be used.

[0073] For the cathode of the organic EL device of the present invention, a metal 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 is used as the electrode material. [Example]

[0074] Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention.

[0075] [Example 1] <Synthesis of biphenyl-4-yl-phenyl-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (2))> A reaction vessel was charged with 49.0 g of 4'-iodo-[1,1':2',1"]terphenyl, 55.3 g of biphenyl-4-yl-phenyl-amino-4-phenylboronic acid, 4.0 g of tetrakis(triphenylphosphine)palladium(0), and 28.5 g of potassium carbonate, and the mixture was refluxed overnight in a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, followed by concentration to obtain a crude product. The crude product was purified by column chromatography (carrier: silica gel, eluent: toluene / n-heptane) to obtain 65.7 g (yield: 86.9%) of biphenyl-4-yl-phenyl-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (2)) as a pale yellow powder.

[0076] [ka]

[0077] [Example 2] <Synthesis of biphenyl-4-yl-{4-(naphthalen-2-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (33))> A reaction vessel was charged with 14.7 g of biphenyl-4-yl-{4-(naphthalen-2-yl)-phenyl}-phenylamine and stirred under ice cooling in dichloromethane. Then, 5.9 g of N-bromosuccinimide was added and stirred overnight at room temperature. After the reaction was complete, H2O was added to the system, and the organic layer was extracted and separated. The organic layer was concentrated to obtain a crude product. The crude product was purified by recrystallization using acetone to obtain 16.7 g of biphenyl-4-yl-(4-bromophenyl)-{4-(naphthalen-2-yl)phenyl}-amine as a white powder (yield: 96.6%).

[0078] [ka]

[0079] Next, 9.0 g of biphenyl-4-yl-(4-bromophenyl)-{4-(naphthalen-2-yl)phenyl}amine, 6.7 g of 4,4,5,5-tetramethyl-2-[1,1':2',1]terphenyl-4'-yl-[1,3,2]dioxaborolane, 0.5 g of tetrakis(triphenylphosphine)palladium(0), and 3.1 g of potassium carbonate were added to a reaction vessel and refluxed overnight under a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, followed by concentration to obtain a crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 7.2 g (yield: 62.3%) of biphenyl-4-yl-{4-(naphthalen-2-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (33)) as a white powder.

[0080] [ka]

[0081] The structure of the obtained white powder was identified using NMR. 1 The following 37 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.07(1H), 7.93(2H), 7.89(1H), 7.79(1H), 7.70(3H), 7.69(1H) , 7.65(2H), 7.63(2H), 7.58(2H), 7.52(3H), 7.47(2H), 7.39-7.18(17H).

[0082] [Example 3] <Synthesis of biphenyl-4-yl-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-([1,1':4',1"]terphenyl-4"-yl)-amine (compound (34))> A reaction vessel was charged with 9.0 g of biphenyl-4-yl-phenyl-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (2)), and the mixture was stirred under ice cooling in dichloromethane solvent. 21.0 g of N-bromosuccinimide was then added and the mixture was stirred overnight at room temperature. After the reaction was completed, H2O was added to the system, and the organic layer was extracted and separated, and concentrated to obtain a crude product. The obtained crude product was purified by crystallization using an acetone / n-heptane mixed solvent, yielding 64.0 g (yield: 85.4%) of biphenyl-4-yl-(4-bromophenyl)-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine as a white powder.

[0083] [ka]

[0084] Subsequently, 9.0 g of biphenyl-4-yl-(4-bromophenyl)-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine, 3.1 g of 4-biphenylboronic acid, 0.4 g of tetrakis(triphenylphosphine)palladium(0), and 2.6 g of potassium carbonate were placed in a reaction vessel and stirred under reflux overnight in a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, followed by concentration to obtain a crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 9.5 g (yield: 94.5%) of a white powder of biphenyl-4-yl-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-([1,1':4',1"]terphenyl-4"-yl)-amine (compound (34)).

[0085] [ka]

[0086] The structure of the obtained white powder was identified using NMR. 1The following 39 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.71(2H), 7.70(4H), 7.66(3H), 7.62(3H), 7.59(2H), 7.56(1H), 7.5 3(1H), 7.48(4H), 7.39(1H), 7.35(1H), 7.30(3H), 7.28(5H), 7.27-7.19(9H).

[0087] [Example 4] <Synthesis of biphenyl-4-yl-{4-(phenanthren-9-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (40))> A reaction vessel was charged with 9.0 g of biphenyl-4-yl-(4-bromophenyl)-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine, 3.5 g of 9-phenanthreneboronic acid, 0.4 g of tetrakis(triphenylphosphine)palladium(0), and 2.6 g of potassium carbonate, and the mixture was refluxed overnight under a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated. The organic layer was concentrated to obtain a crude product. The resulting crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 8.4 g (yield: 80.8%) of biphenyl-4-yl-{4-(phenanthren-9-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (40)) as a white powder.

[0088] [ka]

[0089] The structure of the obtained white powder was identified using NMR. 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.79(1H), 8.73(1H), 8.08(1H), 7.91(1H), 7.74(1H), 7.73-7.54(12H), 7.51(1H), 7.48(2H), 7.44(2H), 7.33(7H), 7.25-7.16(10H).

[0090] [Example 5] Synthesis of {4-(naphthalen-1-yl)-phenyl}-{4-(naphthalen-2-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (43)) A reaction vessel was charged with 9.0 g of (4-bromophenyl)-{4-(naphthalen-1-yl)-phenyl}-{4-(naphthalen-2-yl)-phenyl}amine, 6.1 g of 4,4,5,5-tetramethyl-2-[1,1':2',1]terphenyl-4'-yl-[1,3,2]dioxaborolane, 0.5 g of tetrakis(triphenylphosphine)palladium(0), and 2.8 g of potassium carbonate, and the mixture was refluxed overnight under a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, followed by concentration to obtain the crude product. The obtained crude product was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / n-heptane) to obtain 9.3 g (yield: 82.1%) of white powder of {4-(naphthalen-1-yl)-phenyl}-{4-(naphthalen-2-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (43)).

[0091] [ka]

[0092] The structure of the obtained white powder was identified using NMR. 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.05(2H), 7.91(3H), 7.86(2H), 7.78(1H), 7.70(2H), 7.68(2H), 7.65(2H), 7.57-7.42(9H), 7.36(3H), 7.33(3H), 7.25-7.16(10H).

[0093] [Example 6] <Synthesis of bis{4-(naphthalen-1-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (45))> A reaction vessel was charged with 9.0 g of bis{4-(naphthalen-2-yl)phenyl}-(4-bromophenyl)amine, 6.1 g of 4,4,5,5-tetramethyl-2-[1,1':2',1]terphenyl-4'-yl-[1,3,2]dioxaborolane, 0.5 g of tetrakis(triphenylphosphine)palladium(0), and 2.8 g of potassium carbonate, and the mixture was refluxed overnight under a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, followed by concentration to obtain the crude product. The obtained crude product was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / n-heptane) to obtain 7.6 g (yield: 67.1%) of white powder of bis{4-(naphthalen-1-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (45)).

[0094] [ka]

[0095] The structure of the obtained white powder was identified using NMR. 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.07(2H), 7.92(2H), 7.86(2H), 7.68(2H), 7.66(1H), 7.65(1H), 7.57-7.44(13H), 7.40-7.34(6H), 7.25-7.17(10H).

[0096] [Example 7] <Synthesis of biphenyl-4-yl-{4'-(naphthalen-1-yl)-biphenyl-4-yl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (55))> A reaction vessel was charged with 9.0 g of biphenyl-4-yl-(4-bromophenyl)-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine, 3.9 g of 4-(naphthalen-1-yl)phenylboronic acid, 0.4 g of tetrakis(triphenylphosphine)palladium(0), and 2.6 g of potassium carbonate, and the mixture was refluxed overnight in a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, and concentrated to obtain a crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 9.6 g (yield: 89.1%) of a white powder of biphenyl-4-yl-{4'-(naphthalen-1-yl)-biphenyl-4-yl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (55)).

[0097] [ka]

[0098] The structure of the obtained white powder was identified using NMR. 1 The following 41 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.99(1H), 7.92(1H), 7.88(1H), 7.73(2H), 7.67(1H), 7.66-7.59(7H), 7.56(5H), 7 .53(1H), 7.51(1H), 7.49(1H), 7.47(2H), 7.43(2H), 7.34(1H), 7.29(6H), 7.25-7.16(9H).

[0099] [Example 8] <Synthesis of biphenyl-4-yl-{3'-(naphthalen-1-yl)-biphenyl-4-yl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (58))> A reaction vessel was charged with 9.0 g of biphenyl-4-yl-(4-bromophenyl)-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine, 3.9 g of 3-(naphthalen-1-yl)phenylboronic acid, 0.4 g of tetrakis(triphenylphosphine)palladium(0), and 2.6 g of potassium carbonate, and the mixture was refluxed overnight in a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, and concentrated to obtain a crude product. The obtained crude product was purified by crystallization using an acetone / methanol mixed solvent to obtain 10.4 g (yield: 96.6%) of a white powder of biphenyl-4-yl-{3'-(naphthalen-1-yl)-biphenyl-4-yl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (58)).

[0100] [ka]

[0101] The structure of the obtained white powder was identified using NMR. 1 The following 41 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.97(1H), 7.92(1H), 7.88(1H), 7.74(1H), 7.67(1H), 7.65(1H), 7.64 (1H), 7.60(6H), 7.57-7.49(6H), 7.49-7.40(6H), 7.32(1H), 7.28-7.14(15H).

[0102] [Example 9] <Synthesis of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-{4-(naphthalen-2-yl)-phenyl}-amine (compound (93))> A reaction vessel was charged with 25.0 g of 1-(5-chloro-biphenyl-2-yl)-naphthalene, 32.4 g of biphenyl-4-yl-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl}amine, 3.6 g of tris(dibenzylideneacetone)dipalladium(0), 4.5 g of tricyclohexylphosphine, and 50.6 g of tripotassium phosphate, and the mixture was refluxed overnight under a 1,4-dioxane / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated, followed by concentration to obtain a crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 33.8 g (yield: 81.3%) of an ochre powder of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-amine.

[0103] [ka]

[0104] Subsequently, 8.0 g of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-amine, 4.8 g of 2-(4-bromo-phenyl)-naphthalene, 0.1 g of tris(dibenzylideneacetone)dipalladium(0), 0.2 g of tri-t-butylphosphine, and 1.8 g of sodium t-butoxide were placed in a reaction vessel and stirred under reflux in a toluene solvent for 5 hours. After allowing to cool, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 8.8 g (yield: 79.4%) of a pale yellow powder of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-{4-(naphthalen-2-yl)-phenyl}-amine (compound (93)).

[0105] [ka]

[0106] The structure of the resulting pale yellow powder was identified using NMR. 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.08(1H), 7.94(2H), 7.90(1H), 7.85(1H), 7.80(3H), 7.77(1H), 7.71(5H) , 7.65(2H), 7.59(2H), 7.53(2H), 7.47(4H), 7.42-7.23(10H), 7.16(2H), 7.08(3H).

[0107] [Example 10] <Synthesis of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-([1,1':4',1"]terphenyl-4"-yl)-amine (compound (94))> A reaction vessel was charged with 8.0 g of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-amine, 5.2 g of 4-bromo-[1,1':4',1"]terphenyl, 0.1 g of tris(dibenzylideneacetone)dipalladium(0), 0.2 g of tri-t-butylphosphine, and 1.8 g of sodium t-butoxide, and the mixture was reduced in a toluene solvent for 4 hours. The mixture was stirred under running water. After cooling, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The crude product was purified by recrystallization using acetone to obtain 10.4 g (yield: 90.5%) of a pale yellow powder of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-([1,1':4',1"]terphenyl-4"-yl)-amine (compound (94)).

[0108] [ka]

[0109] The structure of the resulting pale yellow powder was identified using NMR. 1The following 41 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.82(1H), 7.78(1H), 7.75(2H), 7.71-7.63(9H), 7.61(4H), 7.55(2H), 7.50(1H ), 7.46(2H), 7.42(3H), 7.36(4H), 7.29(6H), 7.22(1H), 7.13(1H), 7.11(1H), 7.04(3H).

[0110] [Example 11] <Synthesis of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-{4-(phenanthren-9-yl)-phenyl}-amine (compound (96))> A reaction vessel was charged with 8.0 g of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-amine, 5.6 g of 9-(4-bromo-phenyl)-phenanthrene, 0.1 g of tris(dibenzylideneacetone)dipalladium(0), 0.2 g of tri-t-butylphosphine, and 1.8 g of sodium t-butoxide, and the mixture was refluxed and stirred in toluene for 4 hours. 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 8.1 g (yield: 68.4%) of biphenyl-4-yl-{1'-(naphthalen-1-yl)-[1,2':4',1"]terphenyl-4"-yl}-{4-(phenanthren-9-yl)-phenyl}-amine (compound (96))) as a white powder.

[0111] [ka]

[0112] The structure of the obtained white powder was identified using NMR. 1 The following 41 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.79(1H), 8.73(1H), 8.08(1H), 7.91(1H), 7.82(1H), 7.79(1H), 7.75(3H), 7.70(3H) , 7.67(2H), 7.62(3H), 7.58(3H), 7.50(3H), 7.47-7.30(12H), 7.22(1H), 7.13(2H), 7.04(3H).

[0113] [Example 12] Synthesis of {4-(naphthalen-1-yl)-phenyl}-phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine (compound (148)) A reaction vessel was charged with 20.0 g of 4'-iodo-[1,1':2',1"]terphenyl, 21.9 g of phenyl-{4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-biphenyl-4-yl}-amine, 0.7 g of tetrakis(triphenylphosphine)palladium(0), and 11.6 g of potassium carbonate, and the mixture was refluxed overnight in a toluene / EtOH / HO mixed solvent. After cooling, methanol / HO was added to the system, and the solid was filtered to obtain a crude product. The resulting crude product was purified by crystallization using a monochlorobenzene / acetone mixed solvent to obtain 23.3 g (87.6% yield) of a pale red powder of phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine.

[0114] [ka]

[0115] Subsequently, 8.0 g of phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine, 5.3 g of 1-(4-bromo-phenyl)-naphthalene, 0.2 g of tris(dibenzylideneacetone)dipalladium(0), 0.2 g of tri-t-butylphosphine, and 2.0 g of sodium t-butoxide were placed in a reaction vessel and stirred under reflux in toluene for 4 hours. After allowing to cool, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The resulting crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 10.9 g (yield: 95.4%) of a pale red powder of {4-(naphthalen-1-yl)-phenyl}-phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine (compound (148)).

[0116] [ka]

[0117] The structure of the resulting pale red powder was identified using NMR. 1 The following 37 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.06(1H), 7.94(1H), 7.87(1H), 7.76(3H), 7.73(2H), 7.62(2H) , 7.55(2H), 7.50(2H), 7.44(2H), 7.37(2H), 7.32-7.19(18H), 7.12(1H).

[0118] [Example 13] Synthesis of {4-(naphthalen-2-yl)-phenyl}-phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine (compound (149)) A reaction vessel was charged with 7.5 g of phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine, 4.9 g of 2-(4-bromo-phenyl)-naphthalene, 0.2 g of tris(dibenzylideneacetone)dipalladium(0), 0.2 g of tri-t-butylphosphine, and 1.8 g of sodium t-butoxide, and the mixture was refluxed under stirring in toluene for 4 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 10.4 g (yield: 97.2%) of white powder of {4-(naphthalen-2-yl)-phenyl}-phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine (compound (149)).

[0119] [ka]

[0120] The structure of the obtained white powder was identified using NMR. 1 The following 37 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.03(1H), 7.90(2H), 7.86(1H), 7.76(3H), 7.71(3H), 7.69(1H), 7.65(2H) , 7.58(2H), 7.53(1H), 7.49(1H), 7.47(1H), 7.32(2H), 7.25-7.16(16H), 7.09(1H).

[0121] [Example 14] Synthesis of {4-(phenanthren-9-yl)-phenyl}-phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine (compound (150)) A reaction vessel was charged with 7.5 g of phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine, 5.8 g of 9-(4-bromo-phenyl)-phenanthrene, 0.2 g of tris(dibenzylideneacetone)dipalladium(0), 0.2 g of tri-t-butylphosphine, and 1.8 g of sodium t-butoxide, and the mixture was refluxed and stirred in toluene for 5 hours. After cooling, the mixture was filtered and the filtrate was concentrated to obtain a crude product. The resulting crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 11.0 g (yield: 95.7%) of white powder of {4-(phenanthren-9-yl)-phenyl}-phenyl-(2'-phenyl-[1,1':4',1":4",1"']quaterphenyl-4"'-yl)-amine (compound (150)).

[0122] [ka]

[0123] The structure of the obtained white powder was identified using NMR. 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.79(1H), 8.73(1H), 8.07(1H), 7.90(1H), 7.78-7.56(13H), 7.53(1H), 7.47(2H), 7.25-7.16(9H), 7.38-7.26(9H), 7.10(1H).

[0124] [Example 15] <Synthesis of bis{4-(naphthalen-2-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (44))> A reaction vessel was charged with 12.0 g of bis{4-(naphthalen-2-yl)-phenyl}-(3,4-dichloro-biphenyl-4'-yl)-amine, 6.8 g of phenylboronic acid, 0.9 g of tris(dibenzylideneacetone)dipalladium(0), 1.1 g of tricyclohexylphosphine, and 19.8 g of tripotassium phosphate, and the mixture was refluxed overnight under a 1,4-dioxane / HO mixed solvent. 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: toluene / n-heptane) to obtain 11.6 g (yield: 85.5%) of bis{4-(naphthalen-2-yl)-phenyl}-(2'-phenyl-[1,1':4',1"]terphenyl-4"-yl)-amine (compound (44))) as a white powder.

[0125] [ka]

[0126] The structure of the obtained white powder was identified using NMR. 1 The following 39 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=8.05(2H), 7.90(4H), 7.86(2H), 7.77(2H), 7.68(4H), 7.67(2H), 7.63(2H), 7.49(5H), 7.31(6H), 7.25-7.14(10H).

[0127] [Example 16] <Synthesis of biphenyl-4-yl-{1'-(naphthalen-2-yl)-[1,2':4',1"]terphenyl-4"-yl}-phenyl-amine (compound (103))> A reaction vessel was charged with 25.0 g of 2-chloro-4-bromo-iodobenzene, 14.2 g of 2-naphthaleneboronic acid, 1.8 g of tetrakis(triphenylphosphine)palladium(0), and 21.8 g of potassium carbonate, and the mixture was refluxed overnight under a toluene / EtOH / HO mixed solvent. After cooling, toluene / HO was added to the system, and the organic layer was extracted and separated. The organic layer was concentrated to obtain a crude product. The crude product was purified by column chromatography (carrier: silica gel, eluent: n-heptane) to obtain 18.1 g of 3-chloro-4-(naphthalen-2-yl)-bromobenzene as a white powder (yield: 72.5%).

[0128] [ka]

[0129] Next, 9.4 g of 3-chloro-4-(naphthalen-2-yl)-bromobenzene, 9.0 g of 4-(biphenyl-4-yl-phenyl-amino)-phenylboronic acid, 0.6 g of tetrakis(triphenylphosphine)palladium(0), and 7.1 g of potassium carbonate were charged into a reaction vessel and refluxed overnight under a toluene / EtOH / HO mixed solvent. After cooling, methanol was added to the system, and the solid was filtered to obtain a crude product. The resulting crude product was purified by crystallization using a MCB / methanol mixed solvent to obtain 13.4 g of biphenyl-4-yl-{3-chloro-4-(naphthalen-2-yl)-biphenyl-4'-yl}-phenyl-amine as a white powder (yield: 93.0%).

[0130] [ka]

[0131] Subsequently, 13.5 g of biphenyl-4-yl-{3-chloro-4-(naphthalen-2-yl)-biphenyl-4'-yl}-phenyl-amine, 3.1 g of phenylboronic acid, 0.7 g of tris(dibenzylideneacetone)dipalladium(0), 0.7 g of tricyclohexylphosphine, and 10.3 g of tripotassium phosphate were charged into a reaction vessel, and the mixture was refluxed overnight under stirring in a 1,4-dioxane / HO mixed solvent. After cooling, methanol was added to the system, and the solid was filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a toluene solvent to obtain 10.0 g (yield: 68.9%) of a white powder of biphenyl-4-yl-{1'-(naphthalen-2-yl)-[1,2':4',1"]terphenyl-4"-yl}-phenyl-amine (compound (103))).

[0132] [ka]

[0133] The structure of the obtained white powder was identified using NMR. 1 The following 33 hydrogen signals were detected by H-NMR (DMSO-d6). δ(ppm)=7.85(3H), 7.78(3H), 7.70(2H), 7.64(5H), 7.48(4H), 7.37(3H), 7.23(5H), 7.20-7.06(8H).

[0134] The melting points and glass transition points of the compounds synthesized in Examples 2 to 16 were measured using a high-sensitivity differential scanning calorimeter (DSC3100SA, manufactured by Bruker AXS). Furthermore, 100-nm-thick vapor-deposited films were prepared on ITO substrates using these compounds, and the work functions were measured using an ionization potential measurement device (PYS-202, manufactured by Sumitomo Heavy Industries, Ltd.). The results are summarized in Table 1.

[0135] [Table 1]

[0136] The compounds synthesized in Examples 2 to 16 have glass transition points of 100° C. or higher, which indicates that they are stable in the thin film state.

[0137] The compounds synthesized in Examples 2 to 16 exhibit a suitable energy level compared to the work function of 5.4 eV of common hole transport materials such as NPD and TPD, and have good hole transport ability.

[0138] [Example 17] <Fabrication and evaluation of organic EL devices> As shown in Figure 17, the organic EL device was fabricated by depositing a hole injection layer 3, a hole transport layer 4, an electron blocking 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 glass substrate 1 on which a 50 nm thick ITO film, a 100 nm thick silver alloy reflective film, and a 5 nm thick ITO film were formed in this order was subjected to ultrasonic cleaning in isopropyl alcohol for 20 minutes, and then dried for 10 minutes on a hot plate heated to 250° C. After that, it was subjected to UV ozone treatment for 2 minutes, and then the ITO-coated glass substrate was placed in a vacuum deposition machine and the pressure was reduced to 0.001 Pa or less. Subsequently, a hole injection layer 3 was formed to cover the transparent anode 2 by binary deposition of an electron acceptor (Acceptor-1) having the following structural formula and a compound (HTM-1) having the following structural formula at a deposition rate ratio of Acceptor-1:HTM-1=3:97, to a thickness of 10 nm. On this hole injection layer 3, a compound (HTM-1) having the following structural formula was formed as a hole transport layer 4 to a thickness of 140 nm. On this hole transport layer 4, the compound (33) of Example 2 was formed as an electron blocking layer 5 to a thickness of 5 nm. On this electron blocking layer 5, a compound (EMD-1) having the following structural formula and a compound (EMH-1) having the following structural formula were deposited by binary deposition at a deposition rate ratio of EMD-1:EMH-1=5:95 to form an emitting layer 6 having a thickness of 20 nm. On this light-emitting layer 6, an electron transport layer 7 was formed by binary deposition of a compound (ETM-1) with the following structural formula and a compound (ETM-2) with the following structural formula at a deposition rate ratio of ETM-1:ETM-2=50:50, to a thickness of 30 nm. On this electron transport layer 7, an electron injection layer 8 was formed of lithium fluoride to a thickness of 1 nm. On this electron injection layer 8, a cathode 9 made of a magnesium-silver alloy was formed to a thickness of 12 nm. Finally, a compound (CPL-1) having the following structure was formed as a capping layer 10 to a thickness of 60 nm. The characteristics of the fabricated organic EL device were measured in air at room temperature. The light-emitting characteristics of the fabricated organic EL device were measured by applying a DC voltage, and the results are summarized in Table 2.

[0140] [ka]

[0141] [ka]

[0142] [ka]

[0143] [Example 18] An organic EL device was fabricated under the same conditions as in Example 17, except that compound (93) of Example 9 was used as the material for the electron-blocking layer 5 instead of compound (33) of Example 2. The characteristics of the fabricated organic EL device were measured in the air at room temperature. The measurement results of the light-emitting characteristics when a DC voltage was applied to the fabricated organic EL device are summarized in Table 2.

[0144] [Example 19] An organic EL device was fabricated under the same conditions as in Example 17, except that compound (148) of Example 12 was used as the material for the electron-blocking layer 5 instead of compound (33) of Example 2. The characteristics of the fabricated organic EL device were measured in the atmosphere at room temperature. The measurement results of the luminescence characteristics when a DC voltage was applied to the fabricated organic EL device are summarized in Table 2.

[0145] [Example 20] An organic EL device was fabricated under the same conditions as in Example 17, except that compound (44) of Example 15 was used instead of compound (33) of Example 2 as the material for the electron-blocking layer 5. The characteristics of the fabricated organic EL device were measured in the atmosphere at room temperature. The measurement results of the luminescence characteristics when a DC voltage was applied to the fabricated organic EL device are summarized in Table 2.

[0146] [Example 21] An organic EL device was fabricated under the same conditions as in Example 17, except that compound (103) of Example 16 was used as the material for the electron-blocking layer 5 instead of compound (33) of Example 2. The characteristics of the fabricated organic EL device were measured in the atmosphere at room temperature. The measurement results of the luminescence characteristics when a DC voltage was applied to the fabricated organic EL device are summarized in Table 2.

[0147] [Comparative Example 1] For comparison, an organic EL device was fabricated under the same conditions as in Example 17, except that a compound (HTM-2) having the following structural formula (see, for example, Patent Document 5) was used as the material for the electron-blocking layer 5 instead of the compound (33) in Example 2. The characteristics of the fabricated organic EL device were measured in the atmosphere at room temperature. The measurement results of the light-emitting characteristics when a DC voltage was applied to the fabricated organic EL device are summarized in Table 2.

[0148] [ka]

[0149] Comparative Example 2 For comparison, an organic EL device was fabricated under the same conditions as in Example 17, except that the compound (33) in Example 2 was replaced with a compound (HTM-3) having the following structural formula (see, for example, Patent Document 5) as the material for the electron-blocking layer 5. The characteristics of the fabricated organic EL device were measured in the atmosphere at room temperature. The measurement results of the light-emitting characteristics when a DC voltage was applied to the fabricated organic EL device are summarized in Table 2.

[0150] [ka]

[0151] Using the organic EL devices prepared in Examples 17 to 21 and Comparative Examples 1 and 2, a current density of 10 mA / cm 2 The voltage, luminous efficiency, power efficiency, and device lifespan were measured when a current of 1000 cd / m was applied. The device lifespan was measured when the luminance at the start of light emission (initial luminance) was increased to 1000 cd / m. 2 When driven at a constant current, the luminance was 950 cd / m 2 The time it took for the brightness to decay to 95% (corresponding to 95% of the initial brightness taken as 100%) was measured.

[0152] [Table 2]

[0153] As shown in Table 2, the current density was 10 mA / cm 2 The luminous efficiency when a current of 10.04 to 10.26 cd / A was passed through the organic EL elements of Examples 17 to 21, which was higher than the luminous efficiency of 9.34 to 9.85 cd / A of the organic EL elements of Comparative Examples 1 and 2. The power efficiency was also higher than the luminous efficiency of 8.61 to 9.15 lm / W of the organic EL elements of Comparative Examples 1 and 2, which was higher than the luminous efficiency of 9.56 to 9.66 lm / W of the organic EL elements of Examples 17 to 21. Furthermore, the element lifetime (95% decay) was 425 to 512 hours, which was longer than the luminous efficiency of 223 to 306 hours of the organic EL elements of Comparative Examples 1 and 2.

[0154] As is clear from the above results, the organic EL device of the present invention uses an arylamine compound having high hole mobility and excellent electron blocking ability, and therefore can achieve high luminous efficiency and long life compared to conventional organic EL devices. [Industrial Applicability]

[0155] The organic EL device using the arylamine compound having a specific structure of the present invention can improve the luminous efficiency and durability of the organic EL device, making it possible to expand the use of the organic EL device to, for example, home appliances and lighting. [Explanation of symbols]

[0156] 1. Glass substrate 2 transparent anode 3. Hole injection layer 4. Hole transport layer 5 Electron blocking layer 6. Light-emitting layer 7 Electron transport layer 8 Electron injection layer 9 Cathode 10 Capping Layer

Claims

1. An arylamine compound represented by the following general formula (1): 【Chemical 1】 In the formula, Ar １ and Ar ２ represent, each of which may be the same or different, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted carbazolyl group, wherein the substituent is a naphthyl group; Ar ３ and Ar ４ represent, each of which may be the same or different, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted triphenylsilyl group, a substituted or unsubstituted carbazolyl group, or a substituted or unsubstituted phenanthrenyl group, Ar ３ and Ar ４ at least one of is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted carbazolyl group; L represents an unsubstituted phenylene group or an unsubstituted biphenylene group; R １ ~R ３ represent a hydrogen atom or a deuterium atom, which may be the same or different, n is 2, and L may be the same or different from each other.

2. Ar in the general formula (1) ４ The arylamine compound according to claim 1 , wherein is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted carbazolyl group.

3. 3. An organic electroluminescence device having a pair of electrodes and at least one organic layer sandwiched between them, wherein the organic layer contains the arylamine compound according to claim 1.

4. 4. The organic electroluminescent device according to claim 3, wherein the organic layer is a hole transport layer.

5. 4. The organic electroluminescent device according to claim 3, wherein the organic layer is an electron blocking layer.

6. 4. The organic electroluminescent device according to claim 3, wherein the organic layer is a hole injection layer.

7. 4. The organic electroluminescence device according to claim 3, wherein the organic layer is a light-emitting layer.

8. 10. An electronic device comprising an element having a pair of electrodes and at least one organic layer sandwiched therebetween, wherein the organic layer contains the arylamine compound according to claim 1.

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