Organic electroluminescent elements and electronic devices thereof

Abstract

[Problem] The purpose of the present invention is to provide a compound having a high refractive index and a low extinction coefficient in a capping layer at 450-750 nm in order to improve the light extraction efficiency of an organic EL element. [Solution] By focusing on the fact that a specific arylamine-based compound has excellent thin film stability and durability and that the refractive index can be improved by adjusting the molecular structure, an organic EL device having excellent luminous efficiency was obtained by designing a molecule for use as a material constituting the capping layer.

Description

[Technical Field]

[0001] The present invention relates to self-emissive electronic elements suitable for various display devices, particularly to compounds and elements suitable for organic electroluminescent elements (hereinafter abbreviated as organic EL elements), and more specifically to amine compounds having a benzofuran structure or a benzothiophene structure, and to organic EL elements or electronic devices using said amine compounds. [Background technology]

[0002] In 1987, CWTang et al. at Eastman Kodak made organic light-emitting diodes (OLEDs) practical by developing a multilayer structure in which various roles were assigned to different materials. They layered a phosphor capable of transporting electrons with an organic material capable of transporting holes, and injected both charges into the phosphor layer to cause light emission, achieving 1000 cd / m² at voltages of 10V or less. 2 The above high brightness levels can now be achieved (see Patent Documents 1 and 2).

[0003] To date, many improvements have been made to commercialize organic EL elements, and the various roles of the stacked structure have been further subdivided. In electroluminescent elements where an anode, hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, and cathode are sequentially arranged on a substrate, high efficiency and durability have been achieved by light-emitting elements with a bottom emission structure that emits light from the bottom (see, for example, Non-Patent Document 1).

[0004] In recent years, light-emitting devices with a top-emission structure, which use a metal with a high work function as the anode and emit light from the top, have come into use. In bottom-emission structures, where light is extracted from the bottom where the pixel circuit is located, the area of ​​the light-emitting part is limited. In contrast, top-emission light-emitting devices have the advantage of a wider light-emitting part because the pixel circuit does not obstruct the light as it is extracted from the top. In top-emission light-emitting devices, translucent electrodes such as LiF / Al / Ag (see, for example, Non-Patent Document 2), Ca / Mg (see, for example, Non-Patent Document 3), and LiF / MgAg are used as cathodes.

[0005] In such light-emitting devices, when light emitted from the light-emitting layer is incident on another film, if it is incident at an angle greater than a certain degree, it undergoes total internal reflection at the interface between the light-emitting layer and the other film. As a result, only a portion of the emitted light can be utilized. In recent years, in order to improve the light extraction efficiency, light-emitting devices have been proposed in which a high refractive index "capping layer" is provided on the outside of a low refractive index semi-transparent electrode (see, for example, Non-Patent Documents 2 and 3).

[0006] The effect of the capping layer in a light-emitting element with a top emission structure is Ir(ppy) In a light-emitting element using material 3 as the light-emitting material, the current efficiency was 38 cd / A when there was no capping layer, while in a light-emitting element using ZnSe with a capping layer thickness of 60 nm, an efficiency improvement of approximately 1.7 times was observed, reaching 64 cd / A. Furthermore, it has been shown that the maximum transmittance point of the translucent electrode and the capping layer does not necessarily coincide with the maximum efficiency point, and that the point of maximum light extraction efficiency is determined by interference effects (see, for example, Non-Patent Document 3).

[0007] Conventionally, the use of a highly detailed metal mask has been proposed for forming the capping layer. However, when used under high-temperature conditions, the metal mask becomes distorted by heat, resulting in a decrease in alignment accuracy. Therefore, since ZnSe has a high melting point of over 1100°C (see, for example, Non-Patent Document 3), it cannot be deposited in the correct position using a highly detailed metal mask, potentially affecting the light-emitting element itself. Furthermore, even with film deposition by sputtering, it can affect the light-emitting element, making capping layers composed of inorganic materials unsuitable for use.

[0008] Furthermore, when using tris(8-hydroxyquinoline)aluminum (hereinafter abbreviated as Alq3) as a capping layer to adjust the refractive index (see, for example, Non-Patent Document 2), Alq3 is known as an organic EL material commonly used as a green light-emitting material or electron transport material. However, because it has weak absorption around 450 nm, which is used for blue light-emitting materials, there were problems such as a decrease in color purity and a decrease in light extraction efficiency in the case of blue light-emitting elements.

[0009] Amine compounds containing benzothiophene, which are used in organic EL devices, have been disclosed, but these compounds are mainly used as hole transport materials (see, for example, Patent Documents 3-5).

[0010] To improve the characteristics of organic EL elements and to significantly improve light extraction efficiency, there is a need for capping layer materials that have a high refractive index, a low extinction coefficient, and excellent thin-film stability and durability. [Prior art documents] [Patent Documents]

[0011] [Patent Document 1] Japanese Patent Application Publication No. 8-048656 [Patent Document 2] Patent No. 3194657 [Patent Document 3] Patent No. 4604312

Patent Document 4

Patent Document 5

Patent Document 6

Non-Patent Document

[0012]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0013] An object of the present invention is to provide an organic EL device provided with a capping layer composed of a material that (1) has a high refractive index, (2) has good stability of a thin film, (3) is excellent in durability, (4) is excellent in light resistance, and (5) has no absorption in each wavelength region of blue, green, and red, in order to significantly improve the light extraction efficiency and improve the device characteristics of the organic EL device.

[0014] Physical properties of the material for the capping layer suitable for the present invention can include (1) having a high refractive index, (2) being capable of evaporation, (3) having a stable thin film state, and (4) having a high glass transition temperature. Also, physical properties of the device suitable for the present invention can include (1) having a high light extraction efficiency, (2) having no decrease in color purity, (3) transmitting light without change over time, and (4) having a long lifespan.

Means for Solving the Problems

[0015] Therefore, in order to achieve the above objectives, the inventors focused on the fact that arylamine-based materials have excellent stability and durability in thin films, and designed amine compounds having a specific benzofuran or benzothiophene structure with a high refractive index. They then fabricated organic EL elements using these compounds as materials for the capping layer and diligently evaluated the characteristics of the elements, which led to the completion of the present invention.

[0016] In other words, the present invention provides the following organic EL element.

[0017] 1) An organic EL element having at least an anode electrode, a hole transport layer, a light-emitting layer, an electron transport layer, a cathode electrode, and a capping layer in this order, wherein the organic EL element contains an amine compound represented by the following general formula (1) as the material for the capping layer.

[0018] [ka] (1)

[0019] (In the formula, Ar1 and Ar2 may be the same or different, and represent a monovalent group with either R5 or R6 as the bonding site, represented by the general formula (A) below. Ar3 represents a monovalent group, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group with either R5 or R6 as the bonding site, represented by the general formula (A) below. L1 and L2 may be the same or different, and represent a divalent group of a substituted or unsubstituted aromatic hydrocarbon with 6 to 18 ring constituent atoms, or a divalent group of a substituted or unsubstituted aromatic heterocyclic ring with 6 to 18 ring constituent atoms. L3 represents a divalent group of a substituted or unsubstituted aromatic hydrocarbon with 6 to 18 ring constituent atoms, a divalent group of a substituted or unsubstituted aromatic heterocyclic ring with 6 to 18 ring constituent atoms, or a single bond.)

[0020] [ka] (A)

[0021] (In the formula, X represents an oxygen atom or a sulfur atom. R1 to R4 may be the same or different from each other, and represent a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may be substituted, a cycloalkyl group having 5 to 10 carbon atoms which may be substituted, a linear or branched alkenyl group having 2 to 6 carbon atoms which may be substituted, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may be substituted, a cycloalkyloxy group having 5 to 10 carbon atoms which may be substituted, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aryloxy group, and R1 to R4 bonded to the same benzene ring are single-linked R5 and R6 may be linked to each other via a compound, substituted, or unsubstituted methylene group, oxygen atom, or sulfur atom to form a ring. Either R5 or R6 is a linking group acting as a bonding site, and represents a hydrogen atom, deuterium atom, fluorine atom, chlorine atom, cyano group, nitro group, optionally substituted linear or branched alkyl group having 1 to 6 carbon atoms, optionally substituted cycloalkyl group having 5 to 10 carbon atoms, optionally substituted linear or branched alkenyl group having 2 to 6 carbon atoms, optionally substituted linear or branched alkyloxy group having 1 to 6 carbon atoms, optionally substituted cycloalkyloxy group having 5 to 10 carbon atoms, substituted or unsubstituted aromatic hydrocarbon group, or substituted or unsubstituted aromatic heterocyclic group.

[0022] 2) The organic EL element according to 1) above, characterized in that the general formula (A) has a structure represented by the following general formula (A-1).

[0023] [ka] (A-1)

[0024] (In the formula, the dashed lines represent the joints, and X, R1 to R4, and R6 are as defined in the general formula (A) above.)

[0025] 3) The organic EL element according to 1) above, characterized in that the general formula (A) has a structure represented by the following general formula (A-2).

[0026] [ka] (A-2)

[0027] (In the formula, the dashed lines represent the connection points, and X and R1 to R5 are as defined in the general formula (A) above.)

[0028] 4) The organic EL element according to 1) above, characterized in that L1 and L2 in the general formula (1) are a divalent group obtained by removing two hydrogen atoms from unsubstituted benzene, a divalent group obtained by removing two hydrogen atoms from unsubstituted naphthalene, or a divalent group obtained by removing two hydrogen atoms from unsubstituted biphenyl.

[0029] 5) The organic EL element according to 1) above, characterized in that the amine compound represented by the general formula (1) is represented by the following general formula (1-a).

[0030] [ka] (1-a)

[0031] (In the formulas, X, Ar3, L3, R1-R4, and R6 are as defined in general formula (1) and general formula (A) above.)

[0032] 6) The organic EL element according to 1) above, characterized in that the amine compound represented by general formula (1) is represented by the following general formula (1-b).

[0033] [ka] (1-b)

[0034] (In the formulas, X, Ar3, L3, and R1-R5 are as defined in general formula (1) and general formula (A) above.)

[0035] 7) An organic EL element according to any one of 1) to 6) above, wherein the thickness of the capping layer is in the range of 30 nm to 120 nm.

[0036] 8) An organic EL element according to any one of 1) to 7) above, wherein the refractive index of the capping layer in the range of light wavelengths of 450 nm or more and 750 nm or less is 1.85 or more.

[0037] 9) An electronic device characterized by comprising an organic EL element as described in any of 1) to 8) above.

[0038] In this invention, "unsubstituted" in the context of "substituted or unsubstituted" means that the hydrogen atom is not substituted by a substituent.

[0039] In the present invention, the term "substituted or unsubstituted" specifically refers to: cyano groups, nitro groups, halogen atoms; linear or branched alkyl groups having 1 to 6 carbon atoms, such as methyl groups, ethyl groups, n-propyl groups, isopropyl groups, n-butyl groups, isobutyl groups, tert-butyl groups, n-pentyl groups, isopentyl groups, neopentyl groups, and n-hexyl groups; cycloalkyl groups having 5 to 10 carbon atoms, such as cyclopentyl groups, cyclohexyl groups, cycloheptyl groups, cyclooctyl groups, cyclononyl groups, cyclodecyl groups, and adamantyl groups; linear or branched alkenyl groups having 2 to 6 carbon atoms, such as ethenyl groups, propenyl groups, 2-methylpropenyl groups, 1-butenyl groups, 2-butenyl groups, 3-butenyl groups, and 1,3-butadienyl groups; methyl o Linear or branched alkyloxy groups having 1 to 6 carbon atoms, such as xyloxy, ethyloxy, n-propyloxy, isopropyloxy, n-butyloxy, n-pentyloxy, and n-hexyloxy; cycloalkyloxy groups having 5 to 10 carbon atoms, such as cyclopentyloxy and cyclohexyloxy; aromatic hydrocarbon groups such as phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenantrenyl, fluorenyl, spirobifluorenyl, indenyl, pyrenyl, perilenyl, fluoranthenyl, and triphenylenyl; pyridyl, pyrimidinyl, triazinyl, furyl, pyrrolyl, thienyl, quinolyl, isoquinolyl, benzofuranyl, benzothienyl, indolyl, and carbazolyl groups. ,tree Examples of aromatic heterocyclic groups include noxalinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothienyl, naphthilidinyl, phenanthrolinyl, acridinyl, carbonyl, benzoxazolyl, benzothiazolyl, and phenoxadinyl groups; and aryloxy groups such as phenyloxy and naphthyloxy groups. These substituents may be further substituted with the "substituents" exemplified above. These substituents may also be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form rings. In the present invention, among the "substituents" exemplified above, cyano groups, nitro groups, halogen atoms, methyl groups, ethyl groups, n-propyl groups, methyloxy groups, ethyloxy groups, n-propyloxy groups, and phenyl groups are preferably used.

[0040] In general formula (1), the "divalent groups of substituted or unsubstituted aromatic hydrocarbons with 6 to 18 ring-forming carbon atoms" represented by L1, L2, and L3 can be specifically exemplified by benzene, biphenyl, terphenyl, naphthalene, anthracene, phenanthrene, and fluorene. “Yoshi The term "divalent group of aromatic hydrocarbons" refers to a divalent group formed by removing two hydrogen atoms from the above-mentioned "aromatic hydrocarbons." Here, the "divalent group of aromatic hydrocarbons" preferably refers to a divalent group (phenylene group) formed by removing two hydrogen atoms from benzene, a divalent group formed by removing two hydrogen atoms from biphenyl, or a divalent group formed by removing two hydrogen atoms from naphthalene. Furthermore, as the divalent group (phenylene group) formed by removing two hydrogen atoms from benzene, it is preferable to use a divalent group (1,4-phenylene group) formed by removing two hydrogen atoms from the 1,4-positions of benzene, or a divalent group (1,3-phenylene group) formed by removing two hydrogen atoms from the 1,3-positions of benzene. Furthermore, as the divalent group formed by removing two hydrogen atoms from biphenyl, the divalent group formed by removing two hydrogen atoms from the 4,4'- positions of biphenyl is preferably used. Furthermore, a divalent group formed by removing two hydrogen atoms from naphthalene is a divalent group formed by removing two hydrogen atoms from the 1,4-positions of naphthalene, or Naphthalene A divalent group formed by removing two hydrogen atoms from the 2,7-positions is preferably used. Furthermore, in the present invention, L3 is preferably a single bond.

[0041] Examples of "aromatic heterocycles" in the "divalent groups of substituted or unsubstituted aromatic heterocycles with 6 to 18 ring constituent atoms" represented by L1, L2, and L3 in general formula (1) include pyridine, pyrimidine, quinoline, benzofuran, benzothiophene, benzoxazole, benzothiazole, dibenzofuran, dibenzothiophene, and phenanthroline. “Yoshi The term "divalent group of a heterocycle of the aromatic group" refers to a divalent group formed by removing two hydrogen atoms from the "aromatic heterocycle" described above.

[0042] In the "substituted or unsubstituted aromatic hydrocarbon groups" represented by Ar3 in general formula (1) and R1 to R6 in general formula (A), specific examples of "aromatic hydrocarbon groups" include phenyl group, biphenyl group, terphenyl group, naphthyl group, anthracenyl group, phenantrenyl group, fluorenyl group, spirobifluorenyl group, indenyl group, pyrenyl group, perilenyl group, fluoranthenyl group, and triphenylenyl group. Here, the "aromatic hydrocarbon group" in the "substituted or unsubstituted aromatic hydrocarbon group" represented by Ar3 above is preferably a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, or a phenantrenyl group.

[0043] In the "substituted or unsubstituted aromatic heterocyclic groups" represented by Ar3 in general formula (1) and R1 to R6 in general formula (A), specific examples of "aromatic heterocyclic groups" include pyridyl, pyrimidinyl, triazinyl, furyl, pyrrolyl, thienyl, quinolyl, isoquinolyl, benzofuranyl, benzothienyl, indolyl, carbazolyl, quinoxalinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothienyl, naphthylidinyl, phenanthrolinyl, acridinyl, carbonyl, benzoxazolyl, benzothiazolyl, and phenoxazinyl groups. Here, in the "substituted or unsubstituted aromatic heterocyclic group" represented by Ar3 above, the "aromatic heterocyclic group" is preferably a quinolyl group, isoquinolyl group, benzofuranyl group, benzothienyl group, dibenzofuranyl group, dibenzothienyl group, benzoxazolyl group, or benzothiazolyl group.

[0044] In the general formula (A), the "linear or branched alkyl group having 1 to 6 carbon atoms, which may have substituents" represented by R1 to R6, specifically include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, and n-hexyl groups.

[0045] In the general formula (A), the "cycloalkyl group" represented by R1 to R6, which may have substituents and has 5 to 10 carbon atoms, can specifically include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and adamantyl groups.

[0046] In the general formula (A), the "linear or branched alkenyl group having 2 to 6 carbon atoms, which may have substituents" represented by R1 to R6, specifically include the ethenyl group, propenyl group, 2-methylpropenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, and 1,3-butadienyl group.

[0047] In the general formula (A), the "linear or branched alkyloxy groups having 1 to 6 carbon atoms, which may have substituents," represented by R1 to R6, can specifically include methyloxy group, ethyloxy group, n-propyloxy group, isopropyloxy group, n-butyloxy group, n-pentyloxy group, n-hexyloxy group, and the like.

[0048] In the general formula (A), the "cycloalkyloxy group" represented by R1 to R6, which may have substituents and has 5 to 10 carbon atoms, can specifically be described as a cyclopentyloxy group, a cyclohexyloxy group, and the like.

[0049] In general formula (A), the "substituted or unsubstituted aryloxy groups" represented by R1 to R4 can specifically include phenyloxy groups, naphthyloxy groups, and the like.

[0050] In the organic EL element of the present invention, the thickness of the capping layer is preferably in the range of 30 nm to 120 nm, and more preferably in the range of 40 nm to 80 nm.

[0051] In the organic EL element of the present invention, the refractive index of the capping layer is preferably 1.85 or higher, more preferably 1.88 or higher, and even more preferably 1.92 or higher, in the range of 450 nm to 750 nm in which the wavelength of light transmitted through the capping layer is within that range.

[0052] Furthermore, in the organic EL element of the present invention, the capping layer may be made by stacking or mixing two or more different constituent materials, in which case it is preferable that the constituent materials consist of two or more different compounds selected from the amine compounds represented by the general formula (1) that are suitably used in the organic EL element of the present invention. [Effects of the Invention]

[0053] The present invention provides an organic EL element that significantly improves light extraction efficiency by having a capping layer with a higher refractive index than the transparent or translucent electrodes, which is provided on the outside of the transparent or translucent electrodes. [Brief explanation of the drawing]

[0054] [Figure 1]This figure shows the structural formulas of compounds (1-1) to (1-15), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 2] This figure shows the structural formulas of compounds (1-16) to (1-30), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 3] This figure shows the structural formulas of compounds (1-31) to (1-45), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 4] This figure shows the structural formulas of compounds (1-46) to (1-60), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 5] This figure shows the structural formulas of compounds (1-61) to (1-75), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 6] This figure shows the structural formulas of compounds (1-76) to (1-90), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 7] This figure shows the structural formulas of compounds (1-91) to (1-105), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 8] This figure shows the structural formulas of compounds (1-106) to (1-120), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 9] This figure shows the structural formulas of compounds (1-121) to (1-135), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 10] This figure shows the structural formulas of compounds (1-136) to (1-150), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 11]This figure shows the structural formulas of compounds (1-151) to (1-165), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 12] This figure shows the structural formulas of compounds (1-166) to (1-180), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 13] This figure shows the structural formulas of compounds (1-181) to (1-195), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 14] This figure shows the structural formulas of compounds (1-196) to (1-210), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 15] This figure shows the structural formulas of compounds (1-211) to (1-218), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 16] This figure shows the structural formulas of compounds (1-219) to (1-224), which are amine compounds represented by general formula (1) that are suitably used in the organic EL element of the present invention. [Figure 17] This figure shows the structural formula of compound (1-225), which is an amine compound represented by general formula (1) that is suitably used in the organic EL element of the present invention. [Figure 18] This figure shows the organic EL element configurations of Examples 38-70 and Comparative Examples 1-2. [Modes for carrying out the invention]

[0055] The amine compound represented by the general formula (1), which is suitably used in the organic EL element of the present invention, can itself be synthesized by known methods (see, for example, Patent Document 4).

[0056] Specific examples of amine compounds represented by the general formula (1) that are suitably used in the organic EL element of the present invention are shown in Figures 1 to 17, but the invention is not limited to these compounds.

[0057] The method for producing the amine compound represented by the general formula (1), which is suitably used in the organic EL element of the present invention, is not particularly limited. However, the purification of the compound can be carried out by known methods used for the purification of organic compounds, such as purification by column chromatography, adsorption purification using silica gel, activated carbon, activated clay, etc., and recrystallization or crystallization with a solvent. Finally, purification was carried out by methods such as sublimation purification. The compound can be identified by NMR analysis, etc. It is preferable to measure the melting point, glass transition temperature (Tg), refractive index, and extinction coefficient as physical properties.

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

[0059] The refractive index and extinction coefficient can be measured by fabricating an 80 nm thin film on a silicon substrate and using a spectroscopic measurement device (F10-RT-UV, manufactured by Filmetrics).

[0060] Examples of the structure of the organic EL element of the present invention include, for example, a light-emitting element with a top emission structure consisting of an anode, a hole transport layer, a light-emitting layer, an electron transport layer, a cathode, and a capping layer sequentially on a glass substrate, as well as a structure having a hole injection layer between the anode and the hole transport layer, an electron blocking layer between the hole transport layer and the light-emitting layer, a hole blocking layer between the light-emitting layer and the electron transport layer, and an electron injection layer between the electron transport layer and the cathode. In these multilayer structures, it is possible to omit or combine several organic layers. For example, a configuration in which the hole injection layer and hole transport layer are combined, a configuration in which the hole transport layer and electron blocking layer are combined, a configuration in which the hole blocking layer and electron transport layer are combined, and a configuration in which the electron transport layer and electron injection layer are combined. It is also possible to have a configuration in which two or more organic layers having the same function are stacked. For example, a configuration in which two hole transport layers are stacked, two light-emitting layers are stacked, two electron transport layers are stacked, and two capping layers are stacked.

[0061] The total thickness of each layer of the organic EL element is preferably around 200 nm to 750 nm, and more preferably around 350 nm to 600 nm. The thickness of the capping layer is preferably, for example, 30 nm to 120 nm, and more preferably 40 nm to 80 nm. In this case, good light extraction efficiency can be obtained. The thickness of the capping layer can be appropriately changed depending on the type of light-emitting material used for the light-emitting element, the thickness of each layer of the organic EL element other than the capping layer, etc.

[0062] For the anode of the organic EL element of the present invention, electrode materials with a large work function, such as ITO or gold, are used.

[0063] As the hole injection layer of the organic EL element of the present invention, materials such as arylamine compounds having a structure in which two or more triphenylamine structures are linked in the molecule by single bonds or divalent groups that do not contain heteroatoms, such as benzidine derivatives, starburst-type triphenylamine derivatives, and various triphenylamine tetramers are preferred. In addition, porphyrin compounds represented by copper phthalocyanine, acceptor-type heterocyclic compounds such as hexacyanoazatriphenylene, and coating-type polymer materials can be used. These may be deposited as films on their own, or as monolayers deposited by mixing them with other materials. They may also be used in laminated structures of layers deposited individually, layers deposited by mixing, or layers deposited individually and layers deposited by mixing. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and inkjet.

[0064] As the hole transport layer of the organic EL device of the present invention, it is preferable to use benzidine derivatives such as N,N'-diphenyl-N,N'-di(m-tolyl)benzidine (TPD), N,N'-diphenyl-N,N'-di(α-naphthyl)benzidine (NPD), N,N,N',N'-tetrabiphenylylbenzidine, 1,1-bis[4-(di-4-tolylamino)phenyl]cyclohexane (TAPC), and especially arylamine compounds having a structure in which two triphenylamine structures are linked by single bonds or divalent groups that do not contain heteroatoms, such as N,N,N',N'-tetrabiphenylylbenzidine. It is also preferable to use arylamine compounds having only one triphenylamine structure in the molecule, or arylamine compounds having a structure in which three or more triphenylamine structures are linked by single bonds or divalent groups that do not contain heteroatoms, such as various triphenylamine trimers and tetramers. These materials may be deposited individually, or they may be used as single layers formed by mixing them with other materials. They may also be used in laminated structures, such as layers deposited individually, layers deposited by mixing, or layers deposited individually and layers deposited by mixing. Furthermore, a coating-type polymer material such as poly(3,4-ethylenedioxythiophene) (PEDOT) / poly(styrene sulfonate) (PSS) can be used as the hole injection / transport layer. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0065] Furthermore, in the hole injection layer or hole transport layer, it is preferable to further dope the material commonly used in the layer with trisbromophenylamine hexachloroantimony, radialene derivatives, etc. Also, polymer compounds having the structure of benzidine derivatives such as TPD as a substructure can be used.

[0066] As the electron blocking layer of the organic EL device of the present invention, compounds having electron blocking properties can be used, such as carbazole derivatives such as 4,4',4''-tri(N-carbazolyl)triphenylamine (TCTA), 9,9-bis[4-(carbazole-9-yl)phenyl]fluorene, 1,3-bis(carbazole-9-yl)benzene (mCP), and 2,2-bis(4-carbazole-9-yl-phenyl)adamantane (Ad-Cz), and compounds having a triphenylsilyl group and a triarylamine structure, represented by 9-[4-(carbazole-9-yl)phenyl]-9-[4-(triphenylsilyl)phenyl]-9H-fluorene. These may be deposited individually, or used as a single layer by mixing them with other materials. They may also be used in a laminated structure of layers deposited individually, layers deposited by mixing them, or layers deposited individually and layers deposited by mixing them. These materials can be formed into thin films using known methods such as vapor deposition, spin coating, and inkjet printing.

[0067] As the light-emitting layer of the organic EL element of the present invention, in addition to metal complexes of quinolinol derivatives such as Alq3, various metal complexes, anthracene derivatives, bis-styrylbenzene derivatives, pyrene derivatives, oxazole derivatives, poly(p-phenylenevinylene) derivatives, etc., can be used. The light-emitting layer may also be composed of a host material and a dopant material. Anthracene derivatives are preferably used as the host material, but in addition to the above-mentioned light-emitting materials, heterocyclic compounds having an indole ring as a substructure of the fused ring, heterocyclic compounds having a carbazole ring as a substructure of the fused ring, carbazole derivatives, thiazole derivatives, benzimidazole derivatives, polydialkylfluorene derivatives, etc., can be used. As the dopant material, quinacridone, coumarin, rubrene, perylene and their derivatives, benzopyran derivatives, rhodamine derivatives, aminostyryl derivatives, etc., can be used. These materials may be deposited individually, or they may be used as single layers deposited by mixing them with other materials. They may also be used in a laminated structure consisting of layers deposited individually, layers deposited by mixing, or layers deposited individually and layers deposited by mixing.

[0068] Furthermore, phosphorescent materials can be used as light-emitting materials. As phosphorescent materials, metal complex phosphorescent materials such as iridium and platinum can be used. Green phosphorescent materials such as Ir(ppy)3, blue phosphorescent materials such as Firpic and Fir6, and red phosphorescent materials such as Btp2Ir(acac) are used. As the host material in this case, carbazole derivatives such as 4,4'-di(N-carbazolyl)biphenyl (CBP), TCTA, and mCP can be used as hole-injection and transport host materials. As electron-transport host materials, p-bis(triphenylsilyl)benzene (UGH2) and 2,2',2''-(1,3,5-phenylene)-tris(1-phenyl-1H-benzimidazole) (TPBI) can be used, and high-performance organic EL devices can be fabricated.

[0069] To avoid concentration quenching, it is preferable to dope the phosphorescent luminescent material onto the host material by co-deposition in an amount ranging from 1 to 30 weight percent of the entire luminescent layer.

[0070] Furthermore, it is possible to use materials that emit delayed fluorescence as luminescent materials. These materials can be formed into thin films using known methods such as vapor deposition, spin coating, and inkjet printing.

[0071] As the hole-blocking layer of the organic EL device of the present invention, compounds having hole-blocking properties can be used, such as phenanthroline derivatives like bathocuproine (BCP), metal complexes of quinolinol derivatives like aluminum(III) bis(2-methyl-8-quinolinate)-4-phenylphenolate (BAlq), various rare earth complexes, triazole derivatives, triazine derivatives, pyrimidine derivatives, oxadiazole derivatives, and benzoazole derivatives. These materials may also serve as the electron transport layer material. These materials may be deposited individually, or used as monolayers formed by mixing them with other materials. They may also be used in laminated structures, such as layers deposited individually, layers deposited by mixing, or layers deposited individually and layers deposited by mixing. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0072] As the electron transport layer of the organic EL device of the present invention, metal complexes of quinolinol derivatives such as Alq3 and BAlq, as well as various metal complexes, triazole derivatives, triazine derivatives, pyrimidine derivatives, oxadiazole derivatives, pyridine derivatives, benzimidazole derivatives, benzoazole derivatives, thiadiazole derivatives, anthracene derivatives, carbodiimide derivatives, quinoxaline derivatives, pyridoindole derivatives, phenanthroline derivatives, silole derivatives, etc., can be used. These may be deposited as films on their own, or as monolayers deposited by mixing them with other materials. They may also be used in laminated structures of layers deposited individually, layers deposited by mixing, or layers deposited individually and layers deposited by mixing. These materials can be used to form thin films by known methods such as vapor deposition, spin coating, and inkjet printing.

[0073] As the electron injection layer of the organic EL element of the present invention, alkali metal salts such as lithium fluoride and cesium fluoride, alkaline earth metal salts such as magnesium fluoride, metal complexes of quinolinol derivatives such as lithium quinolinol, metal oxides such as aluminum oxide, or metals such as ytterbium (Yb), samarium (Sm), calcium (Ca), strontium (Sr), and cesium (Cs) can be used, but these can be omitted in the preferred selection of the electron transport layer and cathode.

[0074] Furthermore, in the electron injection layer or electron transport layer, a material that is further doped with a metal such as cesium can be used in addition to the material normally used in the layer.

[0075] As the cathode of the organic EL element of the present invention, electrode materials with a low work function such as aluminum, or alloys with an even lower work function such as magnesium-silver alloy, magnesium-calcium alloy, magnesium-indium alloy, aluminum-magnesium alloy, or materials like ITO and IZO can be used.

[0076] It is preferable to use an amine compound represented by the general formula (1), (1-a), or (1-b) as the capping layer of the organic EL element of the present invention. These materials can be formed into thin films by known methods such as vapor deposition, spin coating, or inkjet printing.

[0077] The amine compound represented by the general formula (1), (1-a), or (1-b) that is suitably used in the organic EL element of the present invention has a wavelength of 450 nm or more. 750 The refractive index within the range of nm or less is preferably 1.85 or higher, more preferably 1.88 or higher, and even more preferably 1.92 or higher.

[0078] Although the above describes an organic EL element with a top emission structure, the present invention is not limited to this, and can be similarly applied to organic EL elements with a bottom emission structure, and organic EL elements with a dual emission structure that emit light from both the top and bottom. In these cases, the electrodes in the direction from which light is extracted from the light-emitting element must be transparent or semi-transparent. [Examples]

[0079] The embodiments of the present invention will be described in detail below with reference to examples, but the present invention is not limited to the following embodiments unless it exceeds the gist of the invention.

[0080] [Example 1] <Synthesis of compounds (1-10)> In a nitrogen-purged reaction vessel, 147 g of 1-bromo-4-iodobenzene, 61.6 g of 2-benzothiophene boronic acid, 600 mL of toluene, 200 mL of ethanol, and an aqueous solution of 71.7 g of potassium carbonate dissolved in 260 mL of purified water were added, and nitrogen gas was passed through for 30 minutes. 4.0 g of tetrakistriphenylphosphine palladium was added, and the mixture was stirred under reflux for 14 hours. After cooling to room temperature, the organic layer was collected by liquid-liquid separation of the reaction mixture. The obtained organic layer was heated, 50 g of silica gel was added at 80°C, and the mixture was stirred for 1 hour. The silica gel was removed by thermal filtration, and the filtrate was concentrated. 300 mL of heptane was added to the residue, and the mixture was stirred at room temperature for 1 hour. The resulting solid was collected by filtration to obtain 54.8 g of yellowish-white powder of 2-(4-bromophenyl)benzothiophene (yield: 54.8%).

[0081] 18.0 g of 2-(4-bromophenyl)benzothiophene, 7.6 g of 4-(9-phenantrenyl)benzeneamine, 180 mL of toluene, and 10.2 g of tert-butoxysodium were added to a nitrogen-purged reaction vessel, and nitrogen gas was passed through for 30 minutes. 0.5 g of trisdibenzylideneacetone dipalladium and 2.2 g of a 50% (w / v) toluene solution of tri-tert-butylphosphine were added, and the mixture was stirred under reflux for 8 hours. After cooling to room temperature, 90 mL of methanol was added, and the precipitated solid was collected by filtration. 80 mL of methanol and 80 mL of water were added to the obtained solid, and the mixture was stirred under reflux for 1 hour. The solid was collected by filtration, 400 mL of chlorobenzene was added, and the mixture was heated to 100°C to dissolve the solid. Then, 8 g of silica gel and 8 g of activated clay were added, and the mixture was stirred for 1 hour. The solid was removed by thermal filtration, and the resulting filtrate was concentrated. 180 mL of methanol was added to the residue and stirred under reflux for 1 hour to obtain 10.5 g of a yellow powder of compound (1-10) (yield: 54.1%).

[0082] [ka] (1-10)

[0083] The structure of the obtained yellow powder was identified using NMR. 1 The following 31 hydrogen signals were detected by 1H-NMR (THF-d8). δ(ppm)=8.80-8.93(2H), 8.08-8.10(1H), 7.96-7.98(1H), 7.86-7.88(2H), 7.57-7.81(15H), 7.29-7.40(10H).

[0084] [Example 2] <Synthesis of compounds (1-34)> In Example 1, the same procedure was carried out by substituting 4-(9-phenantrenyl)benzeneamine with 4-(3-dibenzofuranyl)benzeneamine to obtain 9.7 g (yield: 53%) of the yellow powder compound (1-34).

[0085] [ka] (1-34)

[0086] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=7.94-7.98(2H), 7.73-7.79(5H), 7.56-7.64(8H), 7.43-7.47(3H), 7.16-7.36(11H).

[0087] [Example 3] <Synthesis of compounds (1-7)> In Example 1, 4-(9-phenantrenyl)benzeneamine was used 4-amino-p-terphenyl Alternatively, the same procedure was performed to obtain 7.5 g (yield: 93%) of the yellow powder of compound (1-7).

[0088] [ka] (1-7)

[0089] The structure of the obtained yellow powder was identified using NMR. 1 The following 31 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=7.81(2H), 7.75(2H), 7.67(4H), 7.66-7.63(6H), 7.59(2H), 7.48-7.44(4H), 7.38-7.24(7H), 7.21(4H).

[0090] [Example 4] <Synthesis of compounds (1-29)> In Example 1, the same procedure was carried out by substituting 4-(9-phenantrenyl)benzeneamine with 4-(2-benzothiazolyl)benzeneamine to obtain 10.4 g (yield: 61%) of compound (1-29) as a yellow powder.

[0091] [ka] (1-29)

[0092] The structure of the obtained yellow powder was identified using NMR. 1 The following 26 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.04(1H), 8.00(2H), 7.89(1H), 7.28(2H), 7.77(2H), 7.66(4H), 7.51(2H), 7.48(1H) 、 7.40-7.28(5H), 7.27-7.21(6H).

[0093] [Example 5] <Synthesis of compounds (1-32)> In Example 1, the reaction was carried out similarly, with 4-(9-phenantrenyl)benzeneamine replaced by 4-(1-dibenzofuranyl)benzeneamine. After solid collection, the compound (1-32) was purified by crystallization with tetrahydrofuran and acetone. of 5.1 g of yellow powder (yield: 65%) was obtained.

[0094] [ka] (1-32)

[0095] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=7.82(2H), 7.77(2H), 7.72(1H), 7.68(4H), 7.60-7.56(4H), 7.52-7.48(3H), 7.44(1H), 7.37-7.28(11H), 7.22(1H).

[0096] [Example 6] <Synthesis of compounds (1-33)> In Example 1, the same reaction was carried out by substituting 4-(9-phenantrenyl)benzeneamine with 4-(2-dibenzofuranyl)benzeneamine. After solid collection, crystallization purification using tetrahydrofuran and acetone was performed to obtain 10.2 g (yield: 66%) of compound (1-33) as a yellow powder.

[0097] [ka] (1-33)

[0098] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.16(1H), 8.01(1H), 7.82(2H), 7.76(2H), 7.71-7.59(9H), 7.51-7.47(3H), 7.39-7.28(7H), 7.23(4H).

[0099] [Example 7] <Synthesis of compounds (1-35)> In Example 1, the same reaction was carried out, but with 4-(9-phenantrenyl)benzeneamine replaced by 4-(4-dibenzofuranyl)benzeneamine. After solid collection, crystallization purification using tetrahydrofuran and acetone was performed to obtain 11.1 g (yield: 66%) of compound (1-35) as a yellow powder.

[0100] [ka] (1-35)

[0101] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ (ppm) = 8.00 (1H), 7.93 (1H), 7.91 (2H), 7.83 (2H), 7.77 (2H), 7.67 (4H), 7.63 (2H), 7.50 (2H), 7.48 - 7.42 (2H), 7.39 - 7.26 (11H).

[0102] [Example 8] <Synthesis of Compound (1-37)>[ In Example 1, 4-(9-phenanthrenyl)benzenamine was replaced with 4-(2- Dibenzothienyl )benzenamine, and the same reaction was carried out. After solid collection, crystallization purification using tetrahydrofuran and acetone was performed to obtain 10.2 g (yield: 45%) of a yellow powder of Compound (1-37).

[0103] [Chemical Formula] (1-37)

[0104] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ (ppm) = 8.36 (1H), 8.23 (1H), 7.92 (1H), 7.88 (1H), 7.83 (2H), 7.77 (2H), 7.71 (1H), 7.68 - 7.65 (6H), 7.52 - 7.48 (5H), 7.38 - 7.23 (9H)

[0105] [Example 9] <Synthesis of Compound (1-39)>[ In Example 1, 4-(9-phenanthrenyl)benzenamine was replaced with 4-(4- DibenzothienylBy replacing benzeneamine with the same procedure, 6.6 g (yield: 88%) of compound (1-39) as a yellow powder was obtained.

[0106] [ka] (1-39)

[0107] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.20(1H), 8.16(1H), 7.86(1H), 7.83(2H), 7.77(2H), 7.71(2H), 7.67(4H), 7.57(1H), 7.53-7.47(5H), 7.37-7.26(10H).

[0108] [Example 10] <Synthesis of compounds (1-87)> In Example 1, 4-(9-phenantrenyl)benzeneamine was 4-( 4-Dibenzothienyl) The same reaction was carried out using phthalen-1-ylamine instead. After solid collection, crystallization purification using a toluene / acetone mixed solvent was performed to obtain 6.6 g (yield: 64%) of compound (1-87) as a yellow powder.

[0109] [ka] (1-87)

[0110] The structure of the obtained yellow powder was identified using NMR. 1 The following 31 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.28(1H), 8.25(1H), 8.08(1H), 7.81(2H), 7.78(1H), 7.76-7.72(3H), 7.68(1H) , 7.66-7.62(5H), 7.57(1H), 7.53-7.50(2H), 7.49-7.44(4H), 7.42-7.26(5H), 7.21(4H).

[0111] [Example 11] <Synthesis of compounds (1-95)> In a nitrogen-purged reaction vessel, 4.5 g of 4-(2-naphthyl)benzeneamine, 68 mL of xylene, 14.6 g of 2-(7-bromonaphthalene-2-yl)benzothiophene, 4.9 g of tert-butoxysodium, 0.2 g of trisdibenzylideneacetone dipalladium, and 0.2 g of a 50% (w / v) toluene solution of tri-tert-butylphosphine were added and stirred overnight under heating and reflux. After cooling to room temperature, methanol was added, and the solid was collected by filtration. The obtained solid was purified by crystallization using a chlorobenzene / acetone mixed solvent to obtain 2.9 g (yield: 19%) of compound (1-95) as a yellow powder.

[0112] [ka] (1-95)

[0113] The structure of the obtained yellow powder was identified using NMR. 1 The following 33 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.17(2H), 7.96(2H), 7.91-7.73(13H), 7.65(4H), 7.57(1H), 7.40(2H), 7.38-7.27(9H).

[0114] [Example 12] <Synthesis of compounds (1-96)> In Example 11, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(2-benzoxazolyl)benzeneamine to obtain 5.5 g (yield: 35%) of compound (1-96) as a yellow powder.

[0115] [ka] (1-96)

[0116] The structure of the obtained yellow powder was identified using NMR. 1 The following 30 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.07(1H), 7.95(2H), 7.94-7.74(13H), 7.70(2H), 7.64(2H), 7.62(1H), 7.50(2H), 7.42(2H), 7.38-7.27(5H).

[0117] [Example 13] <Synthesis of compound (1-211)> In Example 11, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(3-dibenzofuranyl)benzeneamine, and the yellow powder compound (1-211) was obtained. ; 8.9 g (yield: 74%) was obtained.

[0118] [ka] (1-211)

[0119] The structure of the obtained yellow powder was identified using NMR. 1 The following 33 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.00(1H), 7.97(1H), 7.95(2H), 7.83(6H), 7.77(5H), 7.64(7H), 7.79(1H), 7.46(1H), 7.42(2H), 7.39-7.27(7H).

[0120] [Example 14] <Synthesis of Compounds (1-152)> In a nitrogen-purged reaction vessel, combine 5.0 g of 4-(2-naphthyl)benzeneamine, 100 mL of toluene, 13.7 g of 2-(4-bromophenyl)benzofuran, and tert-butoxysodium. ; 6.6 g of trisdibenzylideneacetone dipalladium, 0.8 g of tri-tert-butylphosphine in a 50% (w / v) toluene solution, and 0.8 g of tri-tert-butylphosphine were added and stirred overnight under heating reflux. After cooling to room temperature, methanol was added and the solid was collected by filtration. The obtained solid was purified by crystallization using tetrahydrofuran and acetone to obtain 8.2 g (yield: 53%) of compound (1-152) as a yellow powder.

[0121] [ka] (1-152)

[0122] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.05(1H), 7.90(2H), 7.86(1H), 7.79(4H), 7.76(1H), 7.68(2H), 7.57(2H), 7.52(2H), 7.49(2H), 7.32-7.19(10H), 6.95(2H).

[0123] [Example 15] <Synthesis of Compounds (1-153)> In Example 14, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(9-phenantrenyl)benzeneamine to obtain 3.4 g (yield: 31%) of the yellow powder compound (1-153).

[0124] [ka] (1-153)

[0125] The structure of the obtained yellow powder was identified using NMR. 1 The following 31 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.80(1H), 8.74(1H), 8.07(1H), 7.92(1H), 7.83(4H), 7.75(1H), 7.73-7.58(6H), 7.54-7.51(4H), 7.34-7.22(10H), 6.97(2H).

[0126] [Example 16] <Synthesis of Compounds (1-154)> In Example 14, the same reaction was carried out, with 4-(2-naphthyl)benzeneamine replaced by 4-(2-benzoxazolyl)benzeneamine. After solid collection, crystallization purification using a chlorobenzene / acetone mixed solvent was performed to obtain 10.7 g (yield: 75%) of compound (1-154) as a yellow powder.

[0127] [ka] (1-154)

[0128] The structure of the obtained yellow powder was identified using NMR. 1 The following 26 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.15(2H), 7.83(4H), 7.76(1H), 7.58(3H), 7.52(2H), 7.34(2H), 7.32-7.21(10H), 6.99(2H).

[0129] [Example 17] <Synthesis of Compounds (1-158)> In Example 14, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(2-dibenzofuranyl)benzeneamine to obtain 3.8 g (yield: 31%) of the yellow powder compound (1-158).

[0130] [ka] (1-158)

[0131] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.16(1H), 8.01(1H), 7.79(4H), 7.70(1H), 7.64-7.57(6H), 7.53-7.47(3H), 7.38(1H), 7.30-7.21(10H), 6.96(2H).

[0132] [Example 18] <Synthesis of compounds (1-160)> In Example 14, 4-(2-naphthyl)benzeneamine was 4-(2- Dibenzothienyl By replacing benzeneamine with the same procedure, 6.7 g (yield: 40%) of compound (1-160) as a yellow powder was obtained.

[0133] [ka] (1-160)

[0134] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.36(1H), 8.22(1H), 7.91(1H), 7.87(1H), 7.79(4H), 7.70(1H) , 7.66(1H), 7.57(2H), 7.52(2H), 7.48(2H), 7.30-7.21(11H), 6.95(2H).

[0135] [Example 19] <Synthesis of Compound (1-161)> In Example 14, 4-(2-naphthyl)benzeneamine was 4-(4- Dibenzothienyl By replacing benzeneamine with the same procedure, 4.5 g (yield: 42%) of compound (1-161) as a yellow powder was obtained.

[0136] [ka] (1-161)

[0137] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.20(1H), 8.15(1H), 7.86(1H), 7.81(4H), 7.71(2H), 7.58-7.51(6H), 7.47(2H), 7.33-7.21(10H), 6.96(2H).

[0138] [Example 20] <Synthesis of compounds (1-166)> In Example 14, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(3-quinolyl)benzeneamine to obtain 10.7 g (yield: 75%) of compound (1-166) as a yellow powder.

[0139] [ka] (1-166)

[0140] The structure of the obtained yellow powder was identified using NMR. 1 The following 28 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=9.21(1H), 8.30(1H), 8.14(1H), 7.89(1H), 7.80(4H), 7.72(1H), 7.6 7(2H), 7.58(1H), 7.57(2H), 7.52(2H), 7.32(2H), 7.31-7.20(8H), 6.96(2H).

[0141] [Example 21] <Synthesis of compound (1-212)> In Example 14, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-amino-p-terphenyl to obtain 9.2 g (yield: 60%) of the yellow powder compound (1-212).

[0142] [ka] (1-212)

[0143] The structure of the obtained yellow powder was identified using NMR. 1 The following 31 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=7.79(4H), 7.68(4H), 7.65(2H), 7.59(4H), 7.51(2H), 7.47(2H), 7.36(1H), 7.29-7.21(10H), 6.95(2H).

[0144] [Example 22] <Synthesis of compound (1-213)> In Example 14, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(3-dibenzofuranyl)benzeneamine to obtain 5.1 g (yield: 52%) of the yellow powder compound (1-213).

[0145] [ka] (1-213)

[0146] The structure of the obtained yellow powder was identified using NMR. 1 The following 29 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.00(1H), 7.97(1H), 7.81-7.79(5H), 7.66-7.57(6H), 7.52(2H), 7.47(1H), 7.37(1H), 7.30-7.21(10H), 6.96(2H).

[0147] [Example 23] <Synthesis of compound (1-214)> In Example 14, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4'-benzofuran-2-ylbiphenyl-4-ylamine to obtain 11.4 g (yield: 81%) of compound (1-214) as a pale yellow powder.

[0148] [ka] (1-214)

[0149] The structure of the obtained pale yellow powder was identified using NMR. 1 The following 31 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=7.95(2H), 7.80(4H), 7.70(2H), 7.62-7.51(8H), 7.34-7.21(12H), 7.07(1H) 、 6.96 (2H).

[0150] [Example 24] <Synthesis of compound (1-215)> In Example 14, the same procedure was carried out by substituting 4-(2-naphthyl)benzeneamine with 4'-benzoxazole-2-ylbiphenyl-4-ylamine to obtain 7.2 g (yield: 72%) of the yellow powder compound (1-215).

[0151] [ka] (1-215)

[0152] The structure of the obtained yellow powder was identified using NMR. 1 The following 30 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.33(2H), 7.81-7.76(7H), 7.64-7.51(7H), 7.38-7.36(2H), 7.30-7.21(10H), 6.96(2H).

[0153] [Example 25] <Synthesis of compound (1-216)> In Example 14, the same reaction was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(2-phenyl-benzoxazole-6-yl)benzeneamine. After solid collection, recrystallization purification using chlorobenzene was performed to obtain 14.3 g (yield: 70%) of compound (1-216) as a yellow powder.

[0154] [ka] (1-216)

[0155] The structure of the obtained yellow powder was identified using NMR. 1 The following 30 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.28(2H), 7.80(6H), 7.65-7.54(8H), 7.52(2H), 7.31-7.20(10H), 6.96(2H).

[0156] [Example 26] <Synthesis of compound (1-217)> In Example 14, 4-(2-naphthyl)benzeneamine was replaced with 4'-(2-phenyl-benzoxazole-6-yl )bi The same reaction was carried out using phenyl-4-ylamine instead. After solid collection, recrystallization and purification using chlorobenzene were performed to obtain 5.4 g (yield: 53%) of compound (1-217) as a yellow powder.

[0157] [ka] (1-217)

[0158] The structure of the obtained yellow powder was identified using NMR. 1 The following 34 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.29(2H), 7.84(2H), 7.79(4H), 7.72(4H), 7.66(1H), 7.61(2H), 7.56(5H), 7.52(2H), 7.32-7.20(10H), 6.95(2H).

[0159] [Example 27] <Synthesis of compound (1-218)> In Example 14, the same reaction was carried out by substituting 4-(2-naphthyl)benzeneamine with 4-(2-phenyl-benzothiazole-6-yl)benzeneamine. After solid collection, crystallization purification using chlorobenzene was performed to obtain 7.6 g (yield: 80%) of compound (1-218) as a yellow powder.

[0160] [ka] (1-218)

[0161] The structure of the obtained yellow powder was identified using NMR. 1 The following 30 hydrogen signals were detected by 1H-NMR (CDCl3). δ (ppm) = 8.12 (4H), 7.79 (4H), 7.73 (1H), 7.61 (2H), 7.57 (2H), 7.51 (5H), 7.32 - 7.19 (10H), 6.95 (2H).

[0162] [Example 28] [Synthesis of Compound (1 - 219)] 4-(Naphthalen-1-yl)benzenamine; 5 g was added to a nitrogen-substituted reaction vessel, . toluene: 160 mL, 2-(4'-chlorophenyl)benzofuran; 16.6 g, sodium tert-butoxide; 6.8 g, tris(dibenzylideneacetone)dipalladium; 0.9 g, 50% (w / v) toluene solution of tri-tert-butylphosphine; 0.8 g were added, and the mixture was stirred overnight under heating and reflux. After cooling to room temperature, methanol was added, and the solid was collected by filtration. The obtained solid was purified by crystallization using monochlorobenzene and acetone to obtain 11.1 g (yield: 63%) of the yellow powder of Compound (1 - 219). Robi

[0163] [Chemical Formula] (1 - 219)

[0164] The structure of the obtained yellow powder was identified using NMR. 1 The following 37 hydrogen signals were detected by 1H-NMR (THF-d8). δ (ppm) = 8.02 (1H), 7.98 (4H), 7.91 (1H), 7.85 (1H), 7.77 (4H), 7.70 (4H), 7.58 (2H), 7.53 - 7.44 (8H) 、 7.31 (6H), 7.28 - 7.20 (6H).

[0165] [Example 29] <Synthesis of compounds (1-220)> In a nitrogen-purged reaction vessel, 30.0 g of 4-(2-naphthyl)benzeneamine, 300 mL of toluene, 37.4 g of 2-(4-bromophenyl)benzofuran, 26.3 g of tert-butoxysodium, 2.5 g of trisdibenzylideneacetone dipalladium, and 1.7 g of 2,2'-bis(diphenylphosphin)-1,1'-binaphthyl were added and stirred overnight under reflux. After cooling to room temperature, methanol was added, and the precipitated solid was collected by filtration. The obtained solid was purified by crystallization using a chlorobenzene / acetone mixed solvent to obtain 39.4 g (yield: 70%) of yellow powder (4-benzofuran-2-ylphenyl)-(4-naphthalene-2-ylphenyl)amine.

[0166] The obtained (4-benzofuran-2-ylphenyl)-(4-naphthalene-2-ylphenyl)amine: 7.5 g, xylene: 80 mL, 2-(4'-chlorobiphenyl-4-yl ) 6.1 g of tetrahydrofuran, 3.5 g of tert-butoxysodium, 0.2 g of trisdibenzylideneacetone dipalladium, and 0.4 g of a 50% (w / v) toluene solution of tri-tert-butylphosphine were added to a nitrogen-purged reaction vessel and stirred overnight under reflux. After cooling to room temperature, methanol was added, and the precipitated solid was collected by filtration. The obtained solid was purified by crystallization using a tetrahydrofuran / acetone mixed solvent to obtain 10.6 g (yield: 85%) of compound (1-220) as a yellow powder.

[0167] [ka] (1-220)

[0168] The structure of the obtained yellow powder was identified using NMR. 1 The following 33 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.05(1H), 7.95-7.86(5H), 7.80-7.75(3H), 7.71-7.68(4H), 7.6 0(4H), 7.56(1H), 7.53-7.46(4H), 7.37-7.21(9H), 7.07(1H), 6.95(1H).

[0169] [Example 30] <Synthesis of compound (1-221)> In Example 29, the same procedure was carried out by substituting (4-benzofuran-2-ylphenyl)-(4-naphthalene-2-ylphenyl)amine with (4-benzofuran-2-ylphenyl)-(4-dibenzofuran-3-ylphenyl)amine to obtain 7.4 g (yield: 69%) of the yellow powder compound (1-221).

[0170] [ka] (1-221)

[0171] The structure of the obtained yellow powder was identified using NMR. 1 The following 33 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.01-7.93(4H), 7.81-7.78(3H), 7.71(2H), 7.66-7.45(12H), 7.39-7.21(10H), 7.01(1H), 6.96(1H).

[0172] [Example 31] <Synthesis of compound (1-222)> In Example 29, the same reaction was carried out by replacing (4-benzofuran-2-ylphenyl)-(4-naphthalene-2-ylphenyl)amine with (4-benzofuran-2-ylphenyl)-(4-benzoxazole-2-ylphenyl)amine. After solid collection, crystallization purification using a chlorobenzene / acetone mixed solvent was performed to obtain 8.0 g (yield: 96%) of compound (1-222) as a yellow powder.

[0173] [Chemical formula] (1 - 222)

[0174] The structure of the obtained yellow powder was identified using NMR. 1 The following 30 hydrogen signals were detected by 1H-NMR (CDCl3). δ (ppm) = 8.15 (2H), 7.95 (2H), 7.83 (2H), 7.75 (1H), 7.71 (2H), 7.66 - 7.50 (7H), 7.38 - 7.21 (12H), 7.07 (1H), 6.98 (1H).

[0175] [Example 32] [Synthesis of Compound (1 - 223)] (4 - Benzofuran - 2 - yl - phenyl)-(4 - naphthalene - 2 - yl - phenyl)amine; 5.0 g, xylene; 50 mL, 2-(4’ - chlorobiphenyl - 4 - yl) ) benzothiophene; 4.3 g, sodium tert - butoxide; 2.4 g, tris(dibenzylideneacetone)dipalladium; 0.2 g, 50% (w / v) toluene solution of tri - tert - butylphosphine; 0.2 g were added to a nitrogen - substituted reaction vessel and stirred overnight under heating and reflux. After cooling to room temperature, methanol was added, and the precipitated solid was collected by filtration. The obtained solid was purified by crystallization using a mixed solvent of tetrahydrofuran / acetone to obtain 5.7 g (yield: 67%) of the yellow powder of compound (1 - 223).

[0176] [Chemical formula] (1 - 223)

[0177] The structure of the obtained yellow powder was identified using NMR. 1 The following 33 hydrogen signals were detected by 1H-NMR (DMSO - d6). δ(ppm)=8.24(1H), 8.02-7.94(5H), 7.91-7.77(12H), 7.63(2H), 7.53(2H), 7.43-7.21(11H).

[0178] [Example 33] <Synthesis of compound (1-224)> In Example 32, the same procedure was carried out by substituting (4-benzofuran-2-ylphenyl)-(4-naphthalene-2-ylphenyl)amine with (4-benzofuran-2-ylphenyl)-(4-dibenzofuran-3-ylphenyl)amine to obtain 6.6 g (yield: 77%) of the yellow powder compound (1-224).

[0179] [ka] (1-224)

[0180] The structure of the obtained yellow powder was identified using NMR. 1 The following 33 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.00(1H), 7.97(1H), 7.84(1H), 7.81-7.78(6H), 7.68-7.56(11H), 7.52(1H), 7.47(1H), 7.38-7.21(10H), 6.95(1H).

[0181] [Example 34] <Synthesis of compound (1-225)> In Example 32, the same reaction was carried out by replacing (4-benzofuran-2-ylphenyl)-(4-naphthalene-2-ylphenyl)amine with (4-benzofuran-2-ylphenyl)-(4-benzoxazole-2-ylphenyl)amine. After solid collection, crystallization purification using a chlorobenzene / acetone mixed solvent was performed to obtain 7.8 g (yield: 91%) of compound (1-225) as a yellow powder.

[0182] [ka] (1-225)

[0183] The structure of the obtained yellow powder was identified using NMR. 1 The following 30 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.15(2H), 7.88-7.77(6H), 7.75(1H), 7.67(2H), 7.64-7.54(5H), 7.52(1H), 7.40-7.21(12H), 6.98(1H).

[0184] [Example 35] <Synthesis of compounds (1-72)> (4-benzothiophen-2-ylphenyl)-(4- Benzothiazole 7.0 g of (-2-ylphenyl)amine, 70 mL of toluene, 6.1 g of 2-(7-bromonaphthalene-2-yl)benzothiophene, 2.3 g of tert-butoxysodium, 0.4 g of trisdibenzylideneacetone dipalladium, and 0.8 g of a 50% (w / v) toluene solution of tri-tert-butylphosphine were added and stirred overnight under heating reflux. After cooling to room temperature, methanol was added, and the precipitated solid was collected by filtration. The obtained solid was purified by recrystallization using chlorobenzene to obtain 7.4 g (yield: 66%) of compound (1-72) as a yellow powder.

[0185] [ka] (1-72)

[0186] The structure of the obtained yellow powder was identified using NMR. 1 The following 28 hydrogen signals were detected by 1H-NMR (CDCl3). δ(ppm)=8.05(1H), 8.01(2H), 7.98(1H), 7.91-7.77(8H), 7.69-7.63(4H), 7.53(1H), 7.49(1H), 7.39-7.26(10H).

[0187] [Example 36] The glass transition temperature (Tg) and melting point of the amine compound represented by general formula (1) were measured using a high-sensitivity differential scanning calorimeter (Bruker AXS, DSC3100SA). The measurement results are summarized in Table 1. [Table 1]

[0188] Thus, the amine compound represented by general formula (1) that is suitably used in the organic EL element of the present invention has a glass transition temperature (Tg) of 100°C or higher, or does not exhibit a glass transition temperature (Tg), indicating that the thin film state is stable.

[0189] [Example 37] Using an amine compound represented by general formula (1), a vapor-deposited film with a thickness of 80 nm was fabricated on a silicon substrate, and the refractive index n and extinction coefficient k at wavelengths of 450 nm and 750 nm were measured using a spectroscopic measuring device (F10-RT-UV, Filmetrics). For comparison, measurements were also taken for a comparative compound (2-1) with the following structural formula and Alq3 (see, for example, Patent Document 6). The measurement results for refractive index n and extinction coefficient k are summarized in Table 2.

[0190] [ka] (2-1)

[0191] [Table 2]

[0192] As described above, the amine compound represented by general formula (1), which is suitably used in the organic EL element of the present invention, has a refractive index of 1.85 or higher in the wavelength range of 450 to 750 nm, which is higher than the refractive index of the conventional material Alq3 and comparative compound (2-1). Furthermore, the extinction coefficient is low, comparable to that of the conventional material Alq3 and comparative compound (2-1). This indicates that by using the amine compound represented by general formula (1), which is suitably used in the organic EL element of the present invention, as a constituent material for the capping layer, an improvement in the light extraction efficiency of the organic EL element can be expected.

[0193] [Example 38] As shown in Figure 18, the organic EL element was fabricated by pre-forming a reflective ITO electrode as a metal anode 2 on a glass substrate 1, and then depositing the following layers in order: hole injection layer 3, hole transport layer 4, light-emitting layer 5, electron transport layer 6, electron injection layer 7, cathode 8, and capping layer 9.

[0194] Specifically, a metal anode 2 was formed on a glass substrate 1 by sequentially depositing ITO with a thickness of 50 nm, a reflective silver alloy with a thickness of 100 nm, and ITO with a thickness of 5 nm. This was then ultrasonically cleaned in isopropyl alcohol for 20 minutes, and dried on a hot plate heated to 250°C for 10 minutes. After that, UV ozone treatment was performed for 2 minutes, and then this 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 covering the metal anode 2 by binary deposition of an electron acceptor (Acceptor-1) with the following structural formula and a compound (3-1) with the following structural formula, at a deposition rate ratio of (Acceptor-1):compound (3-1)=3:97, to a thickness of 10 nm. On this hole injection layer 3, a hole transport layer 4 was formed using the compound (3-1) with the following structural formula to a thickness of 140 nm. On this hole transport layer 4, two compounds with the following structural formulas (3-2) and (3-3) were deposited as an emissive layer 5 using binary deposition at a deposition rate ratio of compound (3-2):compound (3-3)=5:95 to a thickness of 20 nm. On this emissive layer 5, two compounds with the following structural formulas (3-4) and (3-5) were deposited as an electron transport layer 6 using binary deposition at a deposition rate ratio of compound (3-4):compound (3-5)=50:50 to a thickness of 30 nm. On this electron transport layer 6, lithium fluoride was deposited as an electron injection layer 7 to a thickness of 1 nm. On this electron injection layer 7, a magnesium-silver alloy was deposited as a cathode 8 to a thickness of 12 nm. Finally, compound (1-10) from Example 1 was deposited as a capping layer 9 to a thickness of 60 nm. The characteristics of the fabricated organic EL element were measured in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0195] [ka] (Acceptor-1)

[0196] [ka] (3-1)

[0197] [ka] (3-2)

[0198] [ka] (3-3)

[0199] [ka] (3-4)

[0200] [ka] (3-5)

[0201] [Example 39] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-34) from Example 2 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0202] [Example 40] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-7) from Example 3 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0203] [Example 41] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-29) from Example 4 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0204] [Example 42] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-32) from Example 5 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0205] [Example 43] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-33) from Example 6 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0206] [Example 44] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-35) from Example 7 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0207] [Example 45] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-37) from Example 8 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0208] [Example 46] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-39) from Example 9 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0209] [Example 47] In Example 38, an organic EL element was fabricated under the same conditions as in Example 10, except that the compound (1-87) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0210] [Example 48] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-95) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0211] [Example 49] In Example 38, an organic EL element was fabricated under the same conditions as in Example 12, except that the compound (1-96) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0212] [Example 50] In Example 38, an organic EL element was fabricated under the same conditions as in Example 13, except that the compound (1-211) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0213] [Example 51] In Example 38, an organic EL element was fabricated under the same conditions as in Example 14, except that the compound (1-152) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0214] [Example 52] In Example 38, an organic EL element was fabricated under the same conditions as in Example 15, except that the compound (1-153) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0215] [Example 53] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-154) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0216] [Example 54] In Example 38, an organic EL element was fabricated under the same conditions as in Example 17, except that the compound (1-158) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0217] [Example 55] In Example 38, an organic EL element was fabricated under the same conditions as in Example 18, except that the compound (1-160) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0218] [Example 56] In Example 38, an organic EL element was fabricated under the same conditions as in Example 19, except that the compound (1-161) from Example 1 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0219] [Example 57] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-166) from Example 20 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0220] [Example 58] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-212) from Example 21 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0221] [Example 59] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-213) from Example 22 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0222] [Example 60] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-216) from Example 25 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0223] [Example 61] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-217) from Example 26 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0224] [Example 62] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-218) from Example 27 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0225] [Example 63] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-219) from Example 28 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0226] [Example 64] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-220) from Example 29 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0227] [Example 65] In Example 38, an organic EL element was fabricated under the same conditions as in Example 38, except that the compound (1-221) from Example 30 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0228] [Example 66] In Example 38, an organic EL element was fabricated under the same conditions as in Example 38, except that the compound (1-222) from Example 31 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0229] [Example 67] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-223) from Example 32 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0230] [Example 68] In Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the compound (1-224) from Example 33 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0231] [Example 69] In Example 38, an organic EL element was fabricated under the same conditions as in Example 38, except that the compound (1-225) from Example 34 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0232] [Example 70] In Example 38, an organic EL element was fabricated under the same conditions as in Example 38, except that the compound (1-72) from Example 35 was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0233] [Comparative Example 1] For comparison, in Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that Alq3 was used as the capping layer 9 instead of the compounds (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0234] [Comparative Example 2] For comparison, in Example 38, an organic EL element was fabricated under the same conditions as in Example 1, except that the comparative compound (2-1) was used as the capping layer 9 instead of the compound (1-10) from Example 1. The fabricated organic EL element was subjected to characteristic measurements in air at room temperature. Table 3 summarizes the measurement results of the light emission characteristics when a DC voltage was applied to the fabricated organic EL element.

[0235] Table 3 summarizes the results of measuring the device lifetime using the organic EL devices fabricated in Examples 38-70 and Comparative Examples 1-2. The device lifetime was 10 mA / cm². 2When driven with a constant current, the time it took for the initial brightness to decay to 95% (95% decay) was measured.

[0236] [Table 3]

[0237] As shown in Table 3, the current density is 10 mA / cm². 2 The driving voltage at time was almost the same for the elements of Comparative Examples 1 and 2 and for the elements of Examples 38 to 70, which used an amine compound represented by general formula (1) as the capping layer. However, in terms of brightness, luminous efficiency, power efficiency, and element life, the elements of Examples 38 to 70 showed a significant improvement compared to the elements of Comparative Examples 1 and 2. This indicates that the amine compound represented by general formula (1), which is suitably used in the organic EL elements of the present invention, is a suitable material for the capping layer, and that the high refractive index of the capping layer can significantly improve the light extraction efficiency of the organic EL element. [Industrial applicability]

[0238] The amine compound represented by general formula (1), which is suitably used in the organic EL element of the present invention, has a high refractive index, can significantly improve light extraction efficiency, and maintains a stable thin film state, making it an excellent compound for suitability in organic EL elements. Organic EL elements fabricated using the amine compound represented by general formula (1), which is suitably used in the organic EL element of the present invention, can achieve high efficiency. Furthermore, by using the amine compound represented by general formula (1), which is suitably used in the organic EL element of the present invention and does not absorb in the blue, green, and red wavelength regions, it is particularly suitable when displaying images with good color purity, clarity, and brightness. For example, it has become possible to develop applications in home appliances and lighting. [Explanation of Symbols]

[0239] 1. Glass substrate 2 metal anode 3. Hole injection layer 4. Hole transport layer 5. Emitting layer 6 Electron transport layer 7 Electron injection layer 8 cathode 9. Capping layer

Claims

1. An organic electroluminescent element having at least an anode electrode, a hole transport layer, a light-emitting layer, an electron transport layer, a cathode electrode, and a capping layer in this order, wherein the capping layer contains an amine compound represented by the following general formula (1). 【Chemistry 1】 （１） (wherein, Ar １ , and Ar ２ may be the same as or different from each other, and has a structure represented by the following general formula (A), and represents a monovalent group having either R ５ , or R ６ as a bonding site. Ar ３ has a structure represented by the following general formula (A), and represents a monovalent group having either R ５ , or R ６ as a bonding site, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group. L １ , and L ２ may be the same as or different from each other, and represent a divalent group of a substituted or unsubstituted aromatic hydrocarbon having 6 to 18 ring-constituting carbon atoms, or a divalent group of a substituted or unsubstituted aromatic heterocyclic ring having 6 to 18 ring-constituting atoms. L 3 represents a divalent group of a substituted or unsubstituted aromatic hydrocarbon having 6 to 18 ring-constituting carbon atoms, a divalent group of a substituted or unsubstituted aromatic heterocyclic ring having 6 to 18 ring-constituting atoms, or a single bond.) 【Chemistry 2】 (A) (In the formula, X represents an oxygen atom or a sulfur atom. R １ ~R ４ R may be the same or different from each other and represents a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms which may be substituted, a cycloalkyl group having 5 to 10 carbon atoms which may be substituted, a linear or branched alkenyl group having 2 to 6 carbon atoms which may be substituted, a linear or branched alkyloxy group having 1 to 6 carbon atoms which may be substituted, a cycloalkyloxy group having 5 to 10 carbon atoms which may be substituted, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted aryloxy group, and is bonded to the same benzene ring. １ ~R ４ These may be bonded to each other via single bonds, substituted or unsubstituted methylene groups, oxygen atoms, or sulfur atoms to form a ring. ５ , and R ６ (Either of these is a linking group acting as a bonding site, and represents a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a linear or branched alkyl group having 1 to 6 carbon atoms (which may be substituted), a cycloalkyl group having 5 to 10 carbon atoms (which may be substituted), a linear or branched alkenyl group having 2 to 6 carbon atoms (which may be substituted), a linear or branched alkyloxy group having 1 to 6 carbon atoms (which may be substituted), a cycloalkyloxy group having 5 to 10 carbon atoms (which may be substituted), a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted aromatic heterocyclic group.)

2. The organic electroluminescent element according to claim 1, characterized in that the general formula (A) has a structure represented by the following general formula (A-1). 【Transformation 3】 (A-1) (In the formula, the dashed line represents the joint, X, R) １ ~R ４ , R ６ This is defined as in the general formula (A) above.

3. The organic electroluminescent element according to claim 1, characterized in that the general formula (A) has a structure represented by the following general formula (A-2). 【Chemistry 4】 (A-2) (In the formula, the dashed line represents the joint, X, R) １ ~R ５ This is defined as in the general formula (A) above.

4. L in the general formula (1) １ , and L ２ However, a divalent group can be formed by removing two hydrogen atoms from unsubstituted benzene, and a divalent group can be formed by removing two hydrogen atoms from unsubstituted naphthalene. The organic electroluminescent element according to claim 1, characterized in that it is a divalent group obtained by removing two hydrogen atoms from an unsubstituted biphenyl.

5. The organic electroluminescent element according to claim 1, characterized in that the amine compound represented by the general formula (1) is represented by the following general formula (1-a). 【Transformation 5】 (1-a) (wherein, X, Ar ３ , L ３ , R １ ~R ４ , R ６ This is defined as in general formula (1) and general formula (A) above.

6. The organic electroluminescent element according to claim 1, characterized in that the amine compound represented by the general formula (1) is represented by the following general formula (1-b). 【Transformation 6】 (1-b) (wherein, X, Ar ３ , L ３ , R １ ~R ５ This is defined as in general formula (1) and general formula (A) above.

7. The organic electroluminescent element according to any one of claims 1 to 6, wherein the thickness of the capping layer is in the range of 30 nm to 120 nm.

8. An organic electroluminescent element according to any one of claims 1 to 7, wherein the refractive index of the capping layer in the range of light wavelengths of 450 nm or more and 750 nm or less is 1.85 or more.

9. An electronic device characterized by comprising an organic electroluminescent element according to any one of claims 1 to 8.

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