Arylamine compound, organic electroluminescent element, and electronic device

Abstract

To provide a material for an organic EL element that exhibits excellent hole transport capability and electron blocking capability and high thermal stability in a thin-film state, and an organic EL element that has a low driving voltage and exhibits high emission efficiency and power efficiency.SOLUTION: An arylamine compound represented by the following general formula (1), wherein Ar1 represents a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group, Ar2 to Ar5 may be identical to or different from each other and each represent a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group, R1 to R14 represent a hydrogen atom or a deuterium atom, and m and n each independently represent an integer of 1 to 2).SELECTED DRAWING: None

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 made organic EL devices practical by developing a layered structure element in which various roles are assigned to each material. They layered a phosphor capable of transporting electrons and an organic material capable of transporting holes, and by injecting both charges into the phosphor layer to emit light, they achieved 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 above non-patent documents, the selection of organic materials for an organic EL device has a significant impact on various properties of the device, such as efficiency and durability (see, for example, 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, 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, which supply holes injected from the anode to the light-emitting layer, and enhancing electron blocking properties, which block 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. To achieve even higher efficiency, materials with better electron blocking properties, more stable thin films, and higher heat resistance have been required. Furthermore, although highly durable aromatic amine derivatives have been reported (see, for example, Patent Document 3), these have been 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, substituted carbazole structures and arylamine compounds 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, in devices using these compounds in the hole injection layer or hole transport layer, although improvements have been made in the device life and luminous efficiency, these improvements are still insufficient, and there is a demand for further reductions in driving voltage, improvements in luminous efficiency, and longer 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] Japanese Patent Application Laid-Open No. 2009-076817 [Patent Document 5] Patent No. 7177966 [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 [Problem to be solved by the invention]

[0014] The object of the present invention is to provide a material for an organic EL device that has excellent hole transporting ability and electron blocking ability, and high thermal stability in a thin film state, and also to provide an organic EL device that has a low driving voltage, high luminous efficiency and power efficiency, and a long device life. [Means for solving the problem]

[0015] To achieve the above object, the inventors have focused on the fact that certain triarylamine compounds have excellent hole injection / transport capabilities, electron blocking capabilities, and thin film stability and durability, and have found that by optimizing the structure by introducing substituents at specific positions, the properties of the material can be dramatically improved. Furthermore, in organic EL devices, the luminous efficiency and power efficiency have been improved, and it has become possible to suppress the light-emission onset voltage and practical driving voltage, thereby realizing a longer lifespan than conventional devices, thereby completing the present invention.

[0016] That is, according to the present invention, the following arylamine compounds and organic electroluminescence devices using the same are provided: Devices and electronics are provided.

[0017] 1) An arylamine compound represented by the following general formula (1):

[0018] [ka] (In the formula, Ar1 represents a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group; Ar2 to Ar5 may be the same or different and represent a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group; R1 to R 14 represents a hydrogen atom or a deuterium atom, and m and n each independently represent an integer of 1 or 2.

[0019] 2) The arylamine compound according to 1) above, wherein in the general formula (1), Ar2 to Ar5 may be the same or different and are a group represented by the following general formula (2):

[0020] [ka] (In the formula, R 15 ~R 19 may be the same or different and represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group; R 15 ~R 19 Adjacent groups may be bonded to each other to form a ring.

[0021] 3) In the above general formula (2), R 15 ~R 19 The arylamine compound according to the above 2), wherein is a hydrogen atom.

[0022] 4) The arylamine compound according to 1) above, wherein m or n is 1 in the general formula (1).

[0023] 5) An organic EL device having a pair of electrodes and at least one organic layer sandwiched therebetween, wherein the organic layer contains the arylamine compound according to any one of 1) to 4) above.

[0024] 6) The organic EL device according to the above 5), wherein the organic layer is a hole transport layer.

[0025] 7) The organic EL device according to the above 5), wherein the organic layer is an electron blocking layer.

[0026] 8) The organic EL device according to the above 5), wherein the organic layer is a hole injection layer.

[0027] 9) An electronic device including an electronic element having a pair of electrodes and at least one organic layer sandwiched between them, wherein the organic layer contains the arylamine compound according to any one of 1) to 4) above. [Effects of the Invention]

[0028] The compound of the present invention has excellent hole transporting ability and electron blocking ability, and also has high thermal stability in a thin film state, and is therefore useful as an electron blocking material or hole transporting material. Organic electroluminescence devices using the compound of the present invention as a material for an organic layer can achieve low driving voltage, high luminous efficiency, and long device life. [Brief explanation of the drawings]

[0029] [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 (72) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 7] FIG. 1 shows compounds (73) to (84) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 8] FIG. 1 shows compounds (85) to (96) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 9] FIG. 1 shows compounds (97) to (108) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 10] FIG. 1 shows compounds (109) to (118) as preferred specific examples of the arylamine compound represented by general formula (1). [Figure 11] FIG. 1 is a diagram showing the configurations of the organic EL devices of Examples 8 to 12 and Comparative Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention will be described in detail below. The following description of the constituent elements may be based on representative embodiments or specific examples of the present invention, but the present invention is not limited to such embodiments or specific examples. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0031] In the "substituted or unsubstituted aromatic hydrocarbon group" represented by Ar1 to Ar5 in general formula (1), the aromatic ring constituting the "aromatic hydrocarbon group" (aryl group) may be a monocyclic ring, a fused ring (fused polycyclic aromatic group) in which two or more rings are fused, a linked ring in which two or more rings are linked by a single bond, a linked ring in which two or more rings are linked by a single bond, or a spiro ring in which two or more rings are linked by a spiro bond. The number of carbon atoms in the aromatic ring is selected, for example, from the range of 6 to 30. Specific examples of the "aromatic hydrocarbon group" include a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, an anthryl group, a phenanthryl group, an indenyl group, a pyrenyl group, a perylenyl group, a fluoranthenyl group, a triphenylenyl group, a fluorenyl group, and a spirobifluorenyl group.

[0032] The "aromatic heterocyclic group" (heteroaryl group) in the "substituted or unsubstituted aromatic heterocyclic group" represented by Ar1 to Ar5 in general formula (1) may be a monocyclic ring or a fused ring in which two or more rings are fused. The number of carbon atoms in the aromatic heterocyclic ring is selected from, for example, 2 to 40, and may also be selected from the range of 2 to 20. Specific examples of the "aromatic heterocyclic group" include a pyridyl group, a pyrimidinyl 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, an azafluorenyl group, a diazafluorenyl group, an azaspirobifluorenyl group, a diazaspirobifluorenyl 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, and a carbolinyl group.

[0033] Examples of the "substituents" in the "substituted aromatic hydrocarbon group" and "substituted aromatic heterocyclic group" represented by Ar1 to Ar5 in general formula (1) include deuterium atoms, cyano groups, nitro groups; halogen atoms such as fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms; silyl groups such as trimethylsilyl groups and triphenylsilyl groups; linear or branched alkyl groups having 1 to 6 carbon atoms such as methyl groups, ethyl groups, and propyl groups; linear or branched alkyloxy groups having 1 to 6 carbon atoms such as methyloxy groups, ethyloxy groups, and propyloxy groups; alkenyl groups such as vinyl groups and allyl groups; aryloxy groups such as phenyloxy groups and tolyloxy groups; arylalkyloxy groups such as benzyloxy groups and phenethyloxy groups; 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. 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.

[0034] Ar1 in the general formula (1) is a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenyl group, Preferred are substituted or unsubstituted biphenylyl groups, substituted or unsubstituted terphenylyl groups, substituted or unsubstituted naphthyl groups, substituted or unsubstituted phenanthrenyl groups, substituted or unsubstituted carbazolyl groups, substituted or unsubstituted fluorenyl groups, and substituted or unsubstituted dibenzofuranyl groups, more preferred are substituted or unsubstituted biphenylyl groups, substituted or unsubstituted terphenylyl groups, substituted or unsubstituted fluorenyl groups, and substituted or unsubstituted dibenzofuranyl groups, and most preferred are unsubstituted biphenylyl groups, unsubstituted terphenylyl groups, 9,9-dialkylfluorenyl groups in which the alkyl group has 1 to 6, preferably 1 to 3, carbon atoms, and unsubstituted dibenzofuranyl groups.

[0035] In the general formula (1), Ar2 to Ar5 may be the same or different from one another and are preferably substituted or unsubstituted aromatic hydrocarbon groups, more preferably substituted or unsubstituted phenyl groups, substituted or unsubstituted biphenylyl groups, or substituted or unsubstituted naphthyl groups, and even more preferably substituted or unsubstituted phenyl groups or substituted or unsubstituted biphenylyl groups. Ar2 and Ar4 may be the same, Ar3 and Ar5 may be the same, or Ar2 to Ar5 may all be the same.

[0036] R to R in general formula (1) 14 represents a hydrogen atom or a deuterium atom, but some or all of them may be deuterium atoms.

[0037] In general formula (1), m and n represent integers of 1 to 2, and m may be 1 and n may be 1, m may be 2 and n may be 2, m may be 1 and n may be 2, or m may be 2 and n may be 1. In the present invention, it is preferable that m or n is 1.

[0038] Furthermore, Ar2 to Ar5 may be the same or different from one another and are preferably groups represented by the general formula (2). In the general formula (1), when Ar2 to Ar5 are represented by the general formula (2), R 15 ~R 19 The aromatic ring constituting the "aromatic hydrocarbon group" (aryl group) in the "substituted or unsubstituted aromatic hydrocarbon group" represented by the formula (1) may be a monocyclic ring, a fused ring in which two or more rings are fused (fused polycyclic aromatic group), a linked ring in which two or more rings are linked by a single bond, a linked ring in which two or more rings are linked by a single bond, or a spiro ring in which two or more rings are linked by a spiro bond. Specific examples include the same as those given for the "substituted or unsubstituted aromatic hydrocarbon group" represented by Ar1 to Ar5 in general formula (1).

[0039] In addition, R in general formula (2) 15 ~R 19 The "aromatic heterocyclic group" (heteroaryl group) in the "substituted or unsubstituted aromatic heterocyclic group" represented by the formula (1) may be a monocyclic ring or a fused ring in which two or more rings are fused. The number of carbon atoms in the aromatic heterocyclic ring is selected from, for example, 2 to 40, and may also be selected from the range of 2 to 20. Specific examples include the same as those given for the "substituted or unsubstituted aromatic heterocyclic group" represented by Ar1 to Ar5 in general formula (1).

[0040] R in general formula (2) 15 ~R 19 Examples of the "substituent" in the "substituted or unsubstituted aromatic hydrocarbon group" and "substituted or unsubstituted aromatic heterocyclic group" represented by the above formula (1) include the same as the "substituent" in the "substituted aromatic hydrocarbon group" and "substituted aromatic heterocyclic group" represented by Ar1 to Ar5 in general formula (1).

[0041] R in general formula (2) 15 ~R 19 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.

[0042] In general formula (2), R 15 ~R 19may be the same or different, and are preferably hydrogen atoms or deuterium atoms, and more preferably all are hydrogen atoms.

[0043] The arylamine compound represented by the general formula (1) suitably used in the organic EL device of the present invention is excellent in hole injection / transport ability, thin film stability, and durability, and is therefore preferably used as a constituent material for 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 for the hole transport layer or electron blocking layer.

[0044] 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.

[0045] 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). The arylamine compound represented by general formula (1) can be purified by known methods such as purification by column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., recrystallization or crystallization using a solvent, sublimation purification, etc. The compound can be identified by NMR analysis.

[0046] Among the arylamine 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 Figures 1 to 10, but the compounds are not limited to these. 1 H) is omitted. Also, D is a deuterium atom ( 2 In the arylamine compound represented by general formula (1), all of the hydrogen atoms in the exemplified structure may be replaced with deuterium atoms.

[0047] The compound represented by general formula (1) of the present invention has excellent hole transporting ability and electron blocking ability, and has high thermal stability in a thin film state, and is therefore useful as a material for the organic layer of an organic electroluminescent device. The compound represented by general formula (1) can be used, for example, as a constituent material for the hole injection layer, electron blocking layer, hole transport layer, and light-emitting layer of an organic electroluminescent device, and is particularly useful as a constituent material for the electron blocking layer and hole transport layer.

[0048] 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.

[0049] Furthermore, by using the material of the present invention, 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.

[0050] Physical properties that can be used as indicators of the usefulness of the compound represented by general formula (1) include measurements of the melting point, glass transition point (Tg), and work function (HOMO energy level). The melting point is an indicator of vapor deposition properties, the glass transition point (Tg) is an indicator of the stability of the thin film state, and the work function is an indicator of hole injection properties, hole transport properties, or electron blocking properties.

[0051] The melting point and glass transition point (Tg) can be measured, for example, using a powder with a high-sensitivity differential scanning calorimeter (manufactured by Rigaku, DSCvesta Thermo plus EV02 series).

[0052] The work function (HOMO energy level) 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.).

[0053] <Organic electroluminescence element> The organic electroluminescence device (organic EL device) of the present invention has a pair of electrodes and an organic layer including at least a light-emitting layer between the pair of electrodes, and may include one or more organic layers in addition to the light-emitting layer. Here, the pair of electrodes is an anode and a cathode. The organic layer of the organic EL device of the present invention includes at least an emitting layer, and may include one or more organic layers in addition to the emitting layer. The compound represented by general formula (1) may be contained in the emitting layer or in an organic layer other than the emitting layer, but is preferably contained in an organic layer disposed between the emitting layer and the anode. Specific examples of organic layers disposed between the emitting layer and the anode include a hole injection layer, a hole transport layer, and an electron blocking layer. The compound represented by general formula (1) is preferably contained in the hole transport layer or the electron blocking layer, and more preferably in the electron blocking layer. Materials for these organic layers can be appropriately selected from known materials.

[0054] 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. It may also have 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. It may also have a structure in which two or more organic layers having the same function are stacked, such as a structure in which two hole transport layers are stacked, a structure in which two emitting layers are stacked, or a structure in which two electron transport layers are stacked. The organic EL device of the present invention may have at least an anode, a hole transport layer, an emitting layer, an electron transport layer, and a cathode in the above order, and this does not exclude embodiments in which other layers are present between the layers.

[0055] [anode] The anode of the organic EL device of the present invention is made of an electrode material with a large work function, such as ITO or gold. Materials for the hole injection layer of the organic EL device of the present invention include porphyrin compounds, such as copper phthalocyanine, starburst triphenylamine derivatives, arylamine compounds having two or more triphenylamine or carbazolyl structures in the molecule, each of which is linked by a single bond or a divalent group not containing a 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.

[0056] [Hole injection layer, hole transport layer] The hole injection layer is provided between the anode and the light-emitting layer, or between the anode and the hole transport layer, for example, to lower the injection barrier for holes supplied from the anode, thereby reducing the driving voltage and improving the luminance of light emitted. The hole transport layer is a layer having a function of transporting holes. The hole transport layer may be a hole injection transport layer that also functions as a hole injection layer. Materials that can be used for the hole injection layer of the organic EL device of the present invention include phthalocyanine 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.

[0057] 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.

[0058] Furthermore, for the hole injection layer or the hole transport layer, materials that are normally used for these layers can be 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 can be used.

[0059] The arylamine compound of the present invention represented by general formula (1) 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 can improve the efficiency of hole transport to the light-emitting layer, reduce the driving voltage, and thereby improve the durability of the device, thereby achieving high efficiency, low driving voltage, and long life.

[0060] [Electron blocking layer] The electron blocking layer is disposed, for example, between the light-emitting layer and the hole-transporting layer, and has the function of suppressing the diffusion of electrons present in the light-emitting layer to the outside of the light-emitting layer (toward the hole-transporting layer). This can improve the probability of recombination of electrons and holes in the light-emitting layer. The electron blocking layer usually also has the function of transporting holes. The electron blocking layer may also function as an exciton blocking layer, suppressing the diffusion of excitons from the light-emitting layer. 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.

[0061] The arylamine compound of the present invention has excellent electron blocking ability, high electron tolerance, 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 tolerance.

[0062] [Emitting layer] The light-emitting layer is a layer that emits light after generating excitons by recombination of holes and electrons injected from the anode and cathode, respectively. The light-emitting layer may be used alone as the light-emitting layer, but preferably contains a light-emitting material and a host material. 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.

[0063] 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.

[0064] 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.

[0065] Furthermore, as the light-emitting material, it is also possible to use triazine derivatives such as PIC-TRZ and CC2TA, phenoxazine derivatives such as PXZ-TRZ, and carbazolyldicyanobenzene derivatives (CDCB derivatives) such as 4CzIPN, which emit delayed fluorescence (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.

[0066] The arylamine compound of the present invention represented by general formula (1) has excellent hole-transporting properties and a wide band gap. As a result, an organic EL device having an emissive layer fabricated using the compound as a host material can have a reduced driving voltage and improved luminous efficiency by forming the emissive layer by supporting a fluorescent emitter, a phosphorescent emitter, or a delayed fluorescent emitter, which are called dopants.

[0067] [Hole blocking layer] The hole blocking layer is disposed, for example, between the light emitting layer and the electron transporting layer, and has the function of preventing holes present in the light emitting layer from diffusing outside the light emitting layer (towards the electron transporting layer). 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.

[0068] [Electron transport layer, electron injection layer] The electron injection layer is provided between the cathode and the light-emitting layer, or between the cathode and the electron transport layer, for example, to lower the injection barrier for electrons supplied from the cathode, thereby reducing the driving voltage and improving the luminance of emitted light. The electron transport layer is a layer having a function of transporting electrons. The electron transport layer may also function as an electron injection layer.

[0069] 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.

[0070] 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.

[0071] Furthermore, for the electron injection layer and the electron transport layer, materials that are usually used for these layers and to which a metal such as cesium is added (N-type doping) can be used.

[0072] [cathode] 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.

[0073] The arylamine compound represented by the general formula (1) is preferably used as a constituent material for the hole injection layer, hole transport layer, electron blocking layer, or light emitting layer of the organic EL device of the present invention, and more preferably used as a constituent material for the hole transport layer or electron blocking layer.

[0074] Therefore, the arylamine compound represented by general formula (1) 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.

[0075] <Electronic equipment> The electronic device of the present invention has a pair of electrodes and at least one organic layer disposed between the pair of electrodes, and at least one of the organic layers contains a compound represented by general formula (I). For an explanation of the compound represented by general formula (I), please refer to the description in the above section <Compound represented by general formula (I)>. Examples of the electronic device include a display device and a light-emitting device equipped with an organic EL element, and examples of the display device include display components such as an organic EL panel module, a television, a mobile phone, a tablet, or a personal computer, etc. Examples of the light-emitting device include lighting or a vehicle lamp, etc. [Example]

[0076] 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.

[0077] [Example 1] <Synthesis of compound (1-4)> A reaction vessel was charged with 5.0 g of bis[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-biphenyl-4-ylamine, 6.4 g of 4'-iodo-1,1':2',1"-terphenyl, 3.6 g of potassium carbonate, and 202 mg of tetrakistriphenylphosphinepalladium(0), and the mixture was refluxed and stirred for 8 hours in a mixed solvent of 1,4-dioxane (40 mL) and purified water (12 mL). After cooling, methanol was added and the mixture was filtered to obtain a crude product. The obtained crude product was purified by adsorption with silica gel and then crystallized from toluene to obtain 4.3 g (yield: 63.1%) of bis[4-(1,1':2',1"-terphenyl-4-yl)phenyl]-biphenyl-4-ylamine (compound (1-4)) as a white powder.

[0078] The structure of the resulting compound (1-4) was identified using NMR. 1 The following 43 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.60-7.66(11H),7.49-7.55(4H),7.42-7.44(2H),7.31-7.33(1H),7.17-7.27(25H).

[0079] [ka]

[0080] [Example 2] <Synthesis of compound (1-7)> A reaction vessel was charged with 10.0 g of bis(4-bromophenyl)amine, 22.9 g of 4,4,5,5-tetramethyl-2-(ortho-terphenyl-4'-yl)-1,3,2-dioxaborolane, 12.7 g of potassium carbonate, and 707 mg of tetrakistriphenylphosphinepalladium(0). The mixture was refluxed and stirred for 15 hours in a toluene (100 mL), ethanol (25 mL), and purified water (12 mL) mixture. After cooling, toluene / saturated brine was added to the mixture, and the organic layer was extracted and separated. The crude product was then concentrated to obtain the crude product. The resulting crude product was purified by column chromatography (support: silica gel, eluent: toluene / hexane) to obtain 12.3 g (yield: 64.5%) of bis[para-(ortho-terphenyl-4'-yl)phenyl]amine (Intermediate 1) as a white powder.

[0081] [ka]

[0082] Subsequently, 4.0 g of (bis[para-(ortho-terphenyl-4'-yl)phenyl]amine, 2.2 g of 4-bromoterphenyl, 0.9 g of sodium-t-butoxide, 59 mg of tris(dibenzylideneacetone)dipalladium(0), and 51 mg of tri(t-butyl)phosphine were placed in a reaction vessel and refluxed under stirring in toluene (40 mL) for 2 hours. After cooling, methanol was added and the mixture was filtered to obtain a crude product. The obtained crude product was purified by crystallization using a toluene / acetone mixed solvent to obtain 2.5 g (yield: 46.5%) of a white powder of bis[4-(1,1':2',1"-terphenyl-4'-yl)phenyl]-1,1':4',1"-terphenyl-4-ylamine (compound (1-7))).

[0083] The structure of the resulting compound (1-7) was identified using NMR. 1 The following 47 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.66(4H),7.63-7.64(2H),7.40-7.55(20H),7.33-7.36(1H),7.18-7.24(20H).

[0084] [ka]

[0085] [Example 3] <Synthesis of compound (1-16)> A reaction vessel was charged with 4.0 g of (bis[para-(ortho-terphenyl-4'-yl)phenyl]amine, 1.7 g of 3-bromodibenzofuran, 0.9 g of sodium t-butoxide, 59 mg of tris(dibenzylideneacetone)dipalladium(0), and 51 mg of tri(t-butyl)phosphine, and the mixture was refluxed and stirred in 40 mL of toluene for 2 hours. After cooling, the mixture was filtered to obtain a crude product. The crude product was purified by adsorption using silica gel, and then purified by crystallization using a toluene / acetone mixed solvent, yielding 2.1 g (yield: 40.9%) of a white powder of bis(4-[1,1':2',1"-terphenyl-4'-yl]phenyl)-dibenzofuran-3-ylamine (compound (1-16)).

[0086] The structure of the resulting compound (1-16) was identified using NMR. 1 The following 41 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.85-7.86(1H), 7.78-7.79(1H), 7.40-7.51(17H),7.36-7.39(1H),7.29-7.32(2H),7.17-7.24(18H),7.13-7.15(1H).

[0087] [ka]

[0088] [Example 4] <Synthesis of compound (1-26)> A reaction vessel was charged with 4.0 g of (bis[4-(1,1':2',1"-terphenyl-4'-yl)phenyl]amine, 1.9 g of 2-bromo-9,9-dimethyl-9H-fluorene, 0.9 g of sodium t-butoxide, 59 mg of tris(dibenzylideneacetone)dipalladium(0), and 51 mg of tri(t-butyl)phosphine, and the mixture was refluxed and stirred in 40 mL of toluene for 1 hour. After cooling, the mixture was filtered to obtain a crude product. The crude product was purified by adsorption using silica gel, and then purified by crystallization using a toluene / acetone mixed solvent, yielding 2.8 g (yield: 53.2%) of a white powder of bis(4-[1,1':2',1"-terphenyl-4'-yl]phenyl)-(9,9-dimethyl-9-fluoren-2-yl)amine (compound (1-26)). The structure of the resulting compound (1-26) was identified using NMR. 1 The following 47 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.65(1H),7.60(1H),7.56-7.38(17H),7.35-7.13(21H),7.09(1H),1.43(6H).

[0089] [ka]

[0090] [Example 5] <Synthesis of compound (1-117)> A reaction vessel was charged with 3.3 g of (biphenyl-4-yl)-(4'-phenyl-[1,1':3',1"]terphenyl-4-yl)amine, 3.2 g of 4-bromo-4"-phenyl-[1,1':4',1":3",1"']quaterphenyl, 0.9 g of sodium t-butoxide, 160 mg of tris(dibenzylideneacetone)dipalladium(0), and 140 mg of tri(t-butyl)phosphine, and the mixture was refluxed under stirring for 5 hours in toluene (40 mL). The mixture was stirred. After cooling, the mixture was filtered to obtain a crude product. The obtained crude product was purified by adsorption using silica gel, and the obtained crude product was purified by recrystallization using ethyl acetate solvent to obtain 4.8 g (yield: 81.7%) of a white powder of (biphenyl-4-yl)-(4'-phenyl-[1,1':3',1"]terphenyl-4-yl)-(4"-phenyl-[1,1':4',1":3",1"']quaterphenyl-4-yl)-amine (compound (1-117)). The structure of the resulting compound (1-117) was identified by NMR. 1 The following 47 hydrogen signals were detected by H-NMR (CDCl3). δ(ppm)=7.66(4H),7.60(2H),7.56(2H),7.54-7.42(18H),7.33(1H),7.27-7.18(20H).

[0091] [ka]

[0092] [Example 6] The glass transition temperatures of the arylamine compound represented by general formula (1) and EBM-1, a comparative compound having the following structure disclosed in Patent Document 5, were measured using a high-sensitivity differential scanning calorimeter (Rigaku, DSCvesta Thermo plus EV02 series). The results are summarized in Table 1.

[0093] [ka]

[0094]

Table 1

[0095] The glass transition temperature of the comparative compound (EBM-1) is 103 °C, while the arylamine compound represented by the general formula (1) has a glass transition point of 120 °C or higher, indicating that the thin film state is stable. Therefore, by using the arylamine compound represented by the general formula (1) in an organic EL device, a device with excellent thermal stability can be fabricated.

[0096] [Example 7] <Measurement of HOMO level> An evaporation film with a thickness of 100 nm was formed on an ITO substrate from the arylamine compound represented by the general formula (1) and EBM-1 having the above structure. The results of measuring the work function (corresponding to the absolute value of the HOMO level) by an ionization potential measuring device (Sumitomo Heavy Industries, Ltd., PYS-202) are summarized in Table 2.

[0097]

Table 2

[0098] The arylamine compound represented by the general formula (1) shows a suitable energy level and has good hole transport ability as compared with the work function of 5.4 eV of common hole transport materials such as NPD and TPD.

[0099] [Example 8] <Evaluation of organic EL device> As shown in Fig. 11, the organic EL device was fabricated by sequentially depositing a hole injection layer 3, a hole transport layer 4, an electron blocking layer 5, a light-emitting layer 6, an electron transport layer 7, an electron injection layer 8, a cathode 9, and a capping layer 10 on a glass substrate 1 on which a reflective ITO electrode was previously formed as a transparent anode.

[0100] 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 sequentially formed 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 (BCFN) having the following structural formula at a deposition rate ratio of Acceptor-1:BCFN=3:97, to a thickness of 10 nm. On this hole injection layer 3, a compound (BCFN) 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 (1-4) of Example 1 was formed as an electron blocking layer 5 to a thickness of 5 nm. On this electron blocking layer 5, a compound (Dopant-1) having the following structural formula and a compound (ADN) having the following structural formula were deposited by binary deposition at a deposition rate ratio of Dopant-1:ADN=2:98 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.

[0101] [ka]

[0102] [ka]

[0103] [ka]

[0104] [ka]

[0105] [Example 9] An organic EL device was fabricated under the same conditions as in Example 8, except that compound (1-7) of Example 2 was used instead of compound (1-4) of Example 1 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 3.

[0106] [Example 10] An organic EL device was fabricated under the same conditions as in Example 8, except that compound (1-16) of Example 3 was used instead of compound (1-4) of Example 1 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 3.

[0107] [Example 11] An organic EL device was fabricated under the same conditions as in Example 8, except that compound (1-26) of Example 4 was used instead of compound (1-4) of Example 1 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 3.

[0108] [Example 12] An organic EL device was fabricated under the same conditions as in Example 8, except that compound (1-117) of Example 5 was used instead of compound (1-4) of Example 1 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 3.

[0109] [Comparative Example 1] For comparison, an organic EL device was fabricated under the same conditions as in Example 8, except that EBM-1 having the above structural formula was used as the material for the electron-blocking layer 5 instead of compound (1-4) in Example 1. 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 3.

[0110] The device life was measured using the organic EL devices fabricated in Examples 8 to 12 and Comparative Example 1, and the results are summarized in Table 3. The device life was measured when the luminance at the start of light emission (initial luminance) was 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 of 100%) was measured.

[0111] [Table 3]

[0112] As shown in Table 3, the current density was 10 mA / cm 2 The luminous efficiency when a current of 10.63 cd / A was passed through the organic EL element of Comparative Example 1 was 10.63 cd / A, while the organic EL elements of Examples 8 to 12 were highly efficient at 10.72 to 11.19 cd / A. The power efficiency was also high, at 9.27 to 9.56 lm / W, while the organic EL elements of Comparative Example 1 was 9.12 lm / W. Furthermore, the element lifetime (95% decay) was 363 hours for the organic EL element of Comparative Example 1, at 405 to 476 hours for the organic EL elements of Examples 8 to 12, demonstrating a longer lifetime.

[0113] As is clear from the above results, the organic EL element of the present invention uses an arylamine compound that has high thermal stability and excellent electron blocking ability, and therefore it has been found that it is possible to realize an organic EL element with higher luminous efficiency and longer life than conventional organic EL elements. [Industrial Applicability]

[0114] 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]

[0115] 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): 【Chemistry 1】 (In the formula, Ar １ represents a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group; Ar ２ ~Ar ５ may be the same or different and represent a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aromatic heterocyclic group; R １ ~R １４ represents a hydrogen atom or a deuterium atom, and m and n each independently represent an integer of 1 or 2.

2. In the above general formula (1), Ar ２ ~Ar ５ and may be the same or different from each other and are a group represented by the following general formula (2): 【Chemistry 2】 (In the formula, R １５ ~R １９ may be the same or different and represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group; R １５ ~R １９ Adjacent groups may be bonded to each other to form a ring.

3. In the above general formula (2), R １５ ~R １９ The arylamine compound according to claim 2, wherein is a hydrogen atom.

4. 2. The arylamine compound according to claim 1, wherein m or n is 1 in the general formula (1).

5. 10. An organic EL device comprising 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.

6. 6. The organic EL device according to claim 5, wherein the organic layer is a hole transport layer.

7. 6. The organic EL device according to claim 5, wherein the organic layer is an electron blocking layer.

8. 6. The organic EL device according to claim 5, wherein the organic layer is a hole injection layer.

9. 10. An electronic device including an electronic element 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.

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