JPH0848656A - Compound for organic el element and organic el element - Google Patents

Abstract

PURPOSE:To obtain a compound which can be used as an organic EL element, particularly as a hole infusion transporting layer, because it shows prolonged emission life and high brilliance of high durability and reliability. CONSTITUTION:This compound is represented by the formula (R1-R4 are each an aryl, an alkyl, an alkoxy, amino, halogen; r1-r4 are each 0-5; R5-R6 are each an alkyl, alkoxy, amino, halogen; r5, r6 are each 0-4), for example, N,N,N',N'- tetra(3-biphenylyl)benzidine. This compound is obtained by heating a di(biphenyl) amine compound and a diiodo-biphenyl, or N,N'-diphenylbenzine and a iodobiphenyl in combination, respectively, in the presence of copper. This compound has a high melting point, high glass transition point and the thin film formed by metallization or the like is clear and forms a stabilized amorphous smooth thin film even over the room temperature, thus it can be formed into a thin film by itself in no need of a resin binder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compound for an organic EL device, which is a tetraaryldiamine derivative, and an organic EL.
(Electroluminescence) element

[0002]

2. Description of the Related Art Conventionally, a low molecular weight organic compound which causes conductivity, charge generation, or the like by irradiation with light, that is, a low-molecular weight organic compound having an optical / electronic function is not often capable of forming a thin film by itself. In order to form a film, it was necessary to disperse it in a binder resin, and thus to coat it in a diluted state to form a thin film. In addition, even when it has the ability to form a thin film by a method such as vacuum deposition,
The stability of the thin film was insufficient and it was easy to cause physical changes such as phase transition.

On the other hand, a specific tetraaryldiamine compound is disclosed in JP-A-2-277071 as a material for forming a photosensitive layer of an electrophotographic photoreceptor, but it is not used as a compound for an organic EL device. No suggestion is made.

On the other hand, the organic EL element has a structure in which a thin film containing a fluorescent organic compound is sandwiched between a cathode and an anode,
Excitons (exciton) are generated by injecting electrons and holes (holes) into the thin film and recombining with each other, and light is emitted by utilizing light emission (fluorescence / phosphorescence) when the exciton is deactivated. It is an element.

The characteristic of this organic EL element is that it is capable of high-luminance surface emission of about 100 to 100,000 cd / m ² at a low voltage of 10 V or less, and from blue to red by selecting the type of fluorescent substance. It is possible to emit light.

However, the problem with the organic EL element is that
It has a short emission life, low durability, and low reliability.

Physical changes of organic compounds (Appearance and growth of crystal grain boundaries cause non-uniformity of the interface, which causes deterioration of the charge injection capability of the device, short circuit, and dielectric breakdown. When a low molecular weight compound is used, the appearance and growth of crystal grain boundaries occur and the film properties are significantly reduced.Also, even if the interface such as ITO is rough, the appearance and growth of crystal grain boundaries occur, and the luminous efficiency is improved. It causes a decrease in light emission, current leakage, and no light emission.It also causes a dark spot, which is a partially non-light emitting site.)

Oxidation and peeling of the cathode (Mg, Li, Na, Al, etc. are used as the metal having a small work function for the cathode in order to facilitate the injection of electrons. These metals are water in the atmosphere. When the film is formed by a wet method such as spin coating, the residual solvent and decomposition products during film formation accelerate the oxidation reaction of the electrode. Therefore, peeling of the electrode occurs and dark spots are likely to occur.)

Low luminous efficiency and high calorific value (Because a current is passed through the organic compound, the organic compound must be placed under a high electric field strength and cannot escape from heat generation.
The heat causes deterioration or destruction of the element due to melting, crystallization, thermal decomposition, etc. of the organic compound. )

Examples include photochemical changes and electrochemical changes of the organic compound layer.

As means for solving these problems, an organic EL having a hole injecting and transporting zone composed of a hole injecting porphyrin compound and a hole transporting aromatic tertiary amine
A device is disclosed in Japanese Patent Laid-Open No. 63-295695 (corresponding US Pat. No. 4,720,432). Specifically, in Examples 1, 10 and 11 of JP-A-63-295695, a transparent anode of indium tin oxide coated glass, copper phthalocyanine for hole injection (PC-10) (35 nm, or 37.5 nm), 1,1′-bis (4-di-p-tolylaminophenyl) cyclohexane (ATA-1) (35 nm or 37.5 nm) for hole transport, aluminum trisoxine for light emission and electron injection transport Organic EL formed by (CO-1) (60 nm) and Mg-Ag cathode (200 nm)
A device is disclosed. When this device was driven at a constant current density for 500 hours, the initial output was 0.08 mW / cm ² to 0.05 mW / cm ² (reduction rate 37.5) at 5 mA / cm ^2.
%), And at 20 mA / cm ² , 0.45 mW / cm ² to 0.
066mW / cm ² (reduction rate 86.7%), 40mA / cm ²
Then, from 1.15 mW / cm ² to <0.1 mW / cm ² (reduction rate> 9
1.3%). As another hole-transporting aromatic tertiary amine in Examples 12 and 13, N, N,
N ', N'-tetra-p-tolyl-4,4'-diaminobiphenyl (ATA-7), and N, N, N', N '
-Tetraphenyl-4,4'-diaminobiphenyl (A
Although TA-8) (37.5 nm) is disclosed, the former has a small initial output with respect to the same current density, the output decrease is 62.5%, and the latter is 60% decrease.

Further, triarylamine (ATA-
The combination of 1) and tetraarylamine (ATA-7) is disclosed in Examples 14 and 15, but this also has a small initial output for the same current density and a large output drop. As can be seen from these results, the life of the light emitting element has not yet reached the practical level, and especially when driven at high current density in order to obtain high output (high brightness) emission corresponding to the practical level, The output drop near the operation is abrupt.

For the purpose of improving this sudden output drop, US Pat.
No. 234681 discloses a particularly selected hole-transporting aromatic tertiary amine. Specifically, it is a compound containing at least two tertiary amine components, and the aromatic component bonded to the nitrogen atom of the tertiary amine contains at least two fused aromatic rings. However, it is very difficult to obtain stable light emission over a long period of time even if these specific hole-transporting aromatic tertiary amines are used, and the life of a light-emitting device at a practical level is still insufficient. .

This is because the hole-transporting aromatic tertiary amine specifically disclosed in the above-mentioned specification or the above-mentioned publication has a low thermal property, so that heat generated due to Joule heat of the device causes It is considered that the stability of the thin film in the amorphous state becomes insufficient, and when it is used for an organic EL element, the light emitting efficiency is low, the light emitting life is short, and the durability and reliability are reduced.

The transparent electrode is made of ITO glass or the like because it must have a small surface resistance (10 to 30 Ω / □) or less. However, according to the observation with a scanning tunneling microscope (STM) or atomic force microscope (AFM), it is 20 nm for the sputter-deposition substrate and 40 nm for the EB vapor deposition substrate.
There is unevenness to some extent, and the surface is roughened due to damage during ITO patterning, and the environment is such that crystallization of the organic thin film is easily promoted.

In order to improve this, a metal-containing phthalocyanine or a metal-free phthalocyanine is provided on the surface of ITO (US Pat. No. 4,720,432 or JP-A-63-295695), and polyarylene vinylene is used. Measures such as spin coating have been adopted. However, the metal-containing phthalocyanine and the metal-free phthalocyanine are microcrystals and do not necessarily exhibit the effect.In the case of polyarylene vinylene, the ITO is damaged by the acid at the time of conversion, the oxidation of the electrode is promoted by the residual solvent, and the spin Since it is a non-uniform film formed by coating,
The reliability of the device did not improve.

On the other hand, recently, various EL devices having a mixed layer in which two or more compounds having different functions are mixed have been proposed for the purpose of improving the device performance. For example, Japanese Patent Laid-Open No.
-250292 discloses a thin film or a mixture thin film having a laminated structure of an organic compound having a hole transporting ability and a light emitting function and an organic compound having an electron transporting ability as a light emitting layer for the purpose of improving brightness and durability. JP-A-2-291696 proposes to use a mixture thin film of an organic compound having a hole-transporting function and a fluorescent organic compound having an electron-transporting function as a light-emitting layer. Further, JP-A-3-114197 discloses that a mixed layer in which a charge injection material and an organic phosphor are mixed is provided between the charge injection layer and the light emitting layer for the purpose of improving the light emission efficiency and the light emission brightness. Proposed. Also, Japanese Patent Laid-Open No. 3-190088
In the publication, for the purpose of facilitating the injection of holes and electrons into the light emitting layer, a hole transport layer and //
Alternatively, it has been proposed to provide a mixed layer containing the constituent materials of both facing layers between the electron transport layer and the organic light emitting layer. Further, in JP-A-4-334894, when a plurality of organic compound layers are formed, a layer in which compounds having different functions coexist, for example, a layer containing a hole transporting light emitting material and a hole transporting light emitting material It has been proposed to provide a layer in which the electron-transporting material and the electron-transporting material coexist to increase the luminance of emitted light, exhibit various emission hues, and improve durability. Further, JP-A-5-182762 proposes to form a mixed layer of a light emitting substance and a charge injection substance between the light emitting layer and the charge injection layer to reduce the driving voltage. Further, in JP-A-3-289090, the light-emitting layer is made of a thin film in which a hole-conductive organic compound and an organic complex of a rare earth metal are mixed, and has a narrow emission spectrum width and excellent monochromaticity. It has been proposed to improve efficiency. In addition, Japanese Patent Laid-Open No. 4-178
No. 487 and JP-A-5-78655, a thin film layer in which the component of the organic light emitting thin film layer is a mixture of an organic charge material and an organic light emitting material is provided to prevent concentration quenching and widen the selection range of the light emitting material. It has been proposed that a high-luminance full-color element be used. Further, JP-A-4-357694 proposes to form a graded structure layer in which a concentration gradient is provided by each component forming each layer between layers to reduce the driving voltage and improve the durability. There is.

Further, a structure using rubrene for the organic compound layer has been proposed. As the organic compound layer doped with rubrene, an organic EL device having a hole transport layer formed of a mixed film of a hydrazine derivative and a light emitting layer of tris (8-quinolinolato) aluminum as the organic compound layer is a hole transport layer. It has been proposed that rubrene is doped with rubrene, or that half of the hole transport layer on the organic interface side and the entire light emitting layer are doped with rubrene. When the hole transport layer is doped, light emission occurs from both tris (8-quinolinolato) aluminum and rubrene, and when the hole transport layer and the light emitting layer are doped, emission efficiency is improved. In addition, it has been reported that the increase of dark spots during storage can be suppressed [Kanai, Yajima, Sato, Proceedings of the 39th Joint Lecture on Applied Physics, 28p-Q-8 (1992): Sato, Kanai, Organic Electronics Material Study Group (JOE
M) Workshop 92 Proceedings, 31 (1992)].
Further, it has been proposed that a hole transport layer of a triphenyldiamine derivative (TPD) is doped with rubrene, and it is reported that the luminance half-life is improved [Fujii, Sano, Fujita, Hamada, Shibata, No. Proceedings of 54th Applied Physics Conference, 29p-ZC-7 (1993)].

Further, Japanese Patent Application Laid-Open No. 2-207488 proposes one provided with an organic compound thin film layer composed of a p-type inorganic semiconductor thin film layer and a layer mainly composed of rubrene, and has sufficient emission brightness. It is described that stability of emission brightness can be obtained.

However, none of these EL devices is satisfactory in terms of improving the light emission life.

[0021]

The object of the present invention is, firstly, that it has a high melting point and a glass transition temperature and is excellent in thermal characteristics.
The stability of the thin film in the amorphous state can be sufficiently obtained over a long period of time, and therefore, it can be made into a thin film by itself without using a binder resin, and there is little physical change, photochemical change, or electrochemical change. Organic E which is a specific tetraaryldiamine derivative having photo / electronic functions
It is to provide a compound for an L element.

Secondly, by using this compound for organic EL device, it is possible to realize an organic EL device having a long emission life, high durability, and high brightness. In particular, it is to realize a highly reliable high-brightness light-emitting element in which a voltage rise and a current leak at the time of driving the element, a partial non-light emitting portion appearing and growing, and an initial luminance drop are suppressed.

[0023]

Such an object is achieved by the present invention described in (1) to (41) below. (1) A compound for an organic EL device, which is a tetraaryldiamine derivative represented by the following chemical formula 16.

[0024]

Embedded image

[In the chemical formula 16, R ₁ , R ₂ , R ₃ and R ₄ each represent an aryl group, an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, and R ₁ , R ₂ , R 4 _At least one of ₃ and R ₄ is an aryl group. r1, r2, r3 and r
4 is 0 or an integer of 1 to 5, respectively, r1, r
The sum of 2, r3 and r4 is an integer of 1 or more, and at least one aryl group is present as R _{1 to} R ₄ . R
₅ and R ₆ are each an alkyl group, an alkoxy group,
It represents an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. (2) 2 to ₄ of R _{1 to} R ₄ are aryl groups, and at least 2 of these aryl groups are N.
The compound for an organic EL device according to (1), which is bound to a para position or a meta position with respect to the bonding position of. (3) The compound for organic EL device according to (2), wherein at least one aryl group of R _{1 to} R ₄ is a phenyl group. (4) The compound for organic EL device according to any one of the above (1) to (3), represented by the following chemical formula 17.

[0026]

[Chemical 17]

[In the chemical formula 17, A ₁ , A ₂ , A ₃ and A ₄ are each a phenyl group bonded to the para position or the meta position with respect to the bonding position of N, and these may be the same or different. May be. R ₇ , R ₈ , R ₉ and R
Each of ₁₀ represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r
7, r8, r9 and r10 are each 0 or 1 to 4
Is an integer. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5
And r6 are 0 or an integer of 1 to 4, respectively. (5) The organic EL of (2) above, wherein at least one aryl group of R _{1 to} R ₄ is a naphthyl group, anthryl group, pyrenyl group, perylenyl group or coronenyl group.
Compounds for devices. (6) The compound for organic EL device of the above (1), (2) or (5) represented by the following chemical formula 18.

[0028]

Embedded image

[In chemical formula 18, Ar represents an aryl group bonded to the para position or the meta position with respect to the bonding position of N. Z ₁ , Z ₂ and Z ₃ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. However, at least one of Z ₁ , Z ₂ and Z ₃ represents an aryl group bonded to the para position or the meta position with respect to the bonding position of N, and Ar, Z ₁ ,
Z ₂ and Z ₃ do not become a phenyl group bonded to the para position or meta position with respect to the N bonding position at the same time. s
1, s2 and s3 are each 0 or an integer of 1 to 5, and the sum of s1, s2 and s3 is an integer of 1 or more. R ₀ is an alkyl group, an alkoxy group, an aryl group,
It represents an aryloxy group, an amino group or a halogen atom. r0 is 0 or an integer of 1 to 4, respectively. R
₅ and R ₆ are each an alkyl group, an alkoxy group,
It represents an aryl group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. (7) The compound for organic EL device according to any one of the above (1) to (4), which is represented by the following Chemical Formula 19.

[0030]

[Chemical 19]

[In Chemical Formula 19, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. It may be.
r7, r8, r9 and r10 are each 0 or 1
Is an integer of ~ 4. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r11, r1
2, r13 and r14 are each 0 or an integer of 1 to 5. R ₅ and R ₆ are each an alkyl group,
It represents an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] (8) The above r5, r6, r7, r8, r9, r10, r
The compound for organic EL device of the above (7), wherein 11, r12, r13 and r14 are each 0. (9) The compound for organic EL device according to any one of the above (1) to (4), which is represented by the following Chemical Formula 20.

[0032]

Embedded image

[In Chemical Formula 20, R ₇ , R ₈ , R ₉ and R ₁₀ represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. It may be.
r7, r8, r9 and r10 are each 0 or 1
Is an integer of ~ 4. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r11, r1
2, r13 and r14 are each 0 or an integer of 1 to 5. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r
6 is 0 or an integer of 1 to 4, respectively. ] (10) The r5, r6, r7, r8, r9, r10,
The compound for organic EL devices of the above (9), wherein each of r11, r12, r13 and r14 is 0. (11) The compound for organic EL device according to any one of the above (1) to (4), which is represented by the following Chemical Formula 21.

[0034]

[Chemical 21]

[In the formula 21, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. It may be.
r7, r8, r9 and r10 are each 0 or 1
Is an integer of ~ 4. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r11, r1
2, r13 and r14 are each 0 or an integer of 1 to 5. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r
6 is 0 or an integer of 1 to 4, respectively. ] (12) The r5, r6, r7, r8, r9, r10,
The compound for organic EL devices of the above (11), wherein r11, r12, r13 and r14 are each 0. (13) The compound for organic EL device according to any one of the above (1) to (4), represented by the following chemical formula 22.

[0036]

[Chemical formula 22]

[In the formula 22, R ₇ , R ₈ , R ₉ and R ₁₀ represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. It may be.
r7, r8, r9 and r10 are each 0 or 1
Is an integer of ~ 4. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r11, r1
2, r13 and r14 are each 0 or an integer of 1 to 5. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r
6 is 0 or an integer of 1 to 4, respectively. ] (14) The above r5, r6, r7, r8, r9, r10,
The compound for organic EL devices of the above (13), wherein each of r11, r12, r13 and r14 is 0. (15) The compound for organic EL device according to any one of the above (1) to (4), represented by the following chemical formula 23.

[0038]

[Chemical formula 23]

[In the chemical formula 23, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. It may be.
r7, r8, r9 and r10 are each 0 or 1
Is an integer of ~ 4. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r11, r1
2, r13 and r14 are each 0 or an integer of 1 to 5. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r
6 is 0 or an integer of 1 to 4, respectively. ] (16) The above r5, r6, r7, r8, r9, r10,
The compound for organic EL device of the above (15), wherein each of r11, r12, r13 and r14 is 0. (17) The compound for organic EL device according to any one of the above (1) to (4), which is represented by the following chemical formula 24.

[0040]

[Chemical formula 24]

[In the formula 24, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. It may be.
r7, r8, r9 and r10 are each 0 or 1
Is an integer of ~ 4. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r11, r1
2, r13 and r14 are each 0 or an integer of 1 to 5. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r
6 is 0 or an integer of 1 to 4, respectively. ] (18) The r5, r6, r7, r8, r9, r10,
The compound for organic EL device of the above (17), wherein r11, r12, r13 and r14 are each 0. (19) The above (1), (2), which is represented by the following chemical formula 25:
The compound for organic EL devices according to (5) or (6).

[0042]

[Chemical 25]

[In Chemical Formula 25, Ar ₁ and Ar ₂
Represent aryl groups, which may be the same or different. R ₁₅ and R ₁₆ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r15 and r16
Are each 0 or an integer of 1 to 4. R ₁₇ and R ₁₈ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r17 and r
18 is 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are each 0
Alternatively, it is an integer of 1 to 4. (20) The compound for organic EL devices according to the above (19), wherein each of r5, r6, r15, r16, r17 and r18 is 0. (21) The above (1), (2) represented by the following Chemical Formula 26,
The compound for organic EL devices according to (5) or (6).

[0044]

[Chemical formula 26]

[In chemical formula 26, Ar ₁ and Ar ₃
Represent aryl groups, which may be the same or different. R ₁₅ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r15 and r20
Are each 0 or an integer of 1 to 4. R ₁₅ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r18 and r
19 is 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are each 0
Alternatively, it is an integer of 1 to 4. (22) The compound for organic EL devices according to the above (21), wherein each of r5, r6, r15, r18, r19 and r20 is 0. (23) The above (1), (2), which is represented by the following Chemical Formula 27,
The compound for organic EL devices according to (5) or (6).

[0046]

[Chemical 27]

[In the formula 27, Ar ₁ , Ar ₂ and Ar ₃ each represent an aryl group, and they may be the same or different. R ₁₅ , R ₁₆ and R
₂₀ represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r
15, r16 and r20 are each 0 or 1 to 4
Is an integer. R ₁₈ represents an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom.
r18 is 0 or an integer of 1 to 5. R ₅ and R
₆ represents an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. (24) The compound for an organic EL device according to the above (23), wherein each of r5, r6, r15, r16, r18 and r20 is 0. (25) The above (1), (2), which are represented by the following Chemical Formula 28,
The compound for organic EL devices according to (5) or (6).

[0048]

[Chemical 28]

[In Chemical Formula 28, Ar ₄ and Ar ₅
Represent aryl groups, which may be the same or different. R ₁₅ and R ₁₆ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r15 and r16
Are each 0 or an integer of 1 to 4. R ₁₇ and R ₁₈ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r17 and r
18 is 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are each 0
Alternatively, it is an integer of 1 to 4. (26) The compound for organic EL device according to the above (25), wherein each of r5, r6, r15, r16, r17 and r18 is 0. (27) The above (1), (2),
The compound for organic EL devices according to (5) or (6).

[0050]

[Chemical 29]

[In Chemical formula 29, Ar ₄ and Ar ₆
Represent aryl groups, which may be the same or different. R ₁₅ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r15 and r20
Are each 0 or an integer of 1 to 4. R ₁₈ and R ₁₉ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r18 and r
19 is 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are each 0
Alternatively, it is an integer of 1 to 4. (28) The compound for organic EL devices according to the above (27), wherein each of r5, r6, r15, r18, r19 and r20 is 0. (29) The above (1), (2) represented by the following Chemical Formula 30,
The compound for organic EL devices according to (5) or (6).

[0052]

Embedded image

[In Chemical Formula 30, Ar ₄ , Ar ₅ and Ar ₆ each represent an aryl group, and these may be the same or different. R ₁₅ , R ₁₆ and R
₂₀ represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r
15, r16 and r20 are each 0 or 1 to 4
Is an integer. R ₁₈ represents an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom.
r18 is 0 or an integer of 1 to 5. R ₅ and R
₆ represents an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. (30) The compound for organic EL devices according to the above (29), wherein each of r5, r6, r15, r16, r18 and r20 is 0. (31) An organic EL device having at least one layer containing at least one kind of the compound for organic EL device according to any one of (1) to (30). (32) The organic EL device according to (31), which has at least one layer containing at least one compound of the organic EL device compound and a mixture of at least one compound having an electron injecting and transporting function. (33) The organic EL device according to the above (32), wherein the compound having an electron transporting function is tris (8-quinolinolato) aluminum. (34) The organic EL device according to the above (32) or (33), wherein the layer containing the mixture is a light emitting layer. (35) The organic EL device according to any one of (31) to (34), wherein at least one layer containing at least one kind of the compound for organic EL device is doped with a fluorescent substance. (36) The organic EL device according to the above (35), wherein the fluorescent substance is rubrene. (37) Any of the above (31) to (36), wherein the layer containing at least one kind of the compound for organic EL device is a hole injecting and transporting layer, and having the hole injecting and transporting layer and the light emitting layer. Organic EL device. (38) The organic EL device according to (37), wherein the hole injecting and transporting layer is composed of two or more layers having different compositions. (39) The organic EL device according to the above (38), wherein at least one layer of the hole injecting and transporting layer contains polythiophene. (40) The organic EL device according to any one of (37) to (39), which has an electron injecting and transporting layer. (41) The layer containing at least one kind of the compound for organic EL device is a layer having a hole injecting and transporting function,
A layer having a light emitting function or a layer having an electron injecting and transporting function is provided in contact with this layer, and a layer having the hole injecting and transporting function and a layer having the light emitting function or a layer having an electron injecting and transporting function are provided. The difference in ionization potential Ip is 0.25 eV or more (31), (35) or (3)
6) Organic EL device.

[0054]

The tetraaryldiamine derivative represented by Chemical formula 16, which is the compound for organic EL device of the present invention, has a high melting point and glass transition temperature, and the thin film formed by vapor deposition thereof is transparent and stable even at room temperature or higher. It forms an amorphous state and shows a smooth and good film quality for a long period of time.

Therefore, without using a binder resin,
It can be thinned by itself.

This effect is considered to be due to the following.

Increasing the molecular weight to a high melting point. Optimize the intermolecular overlap by introducing bulky substituents such as the sterically hindered phenyl group. The number of conformations that the molecule can have is large, which hinders the rearrangement of the molecule.

Further, the molecule contains a large number of hole injecting and transporting units such as N-phenyl group, and by introducing a phenyl group into R _{1 to} R ₄ to form a biphenyl group, the π-conjugated system is widened and carrier transfer is facilitated. It is advantageous, and the hole injecting and transporting ability is also very excellent.

Therefore, the organic EL device of the present invention is
Since a tetraaryldiamine derivative represented by is used as an organic EL device compound in an organic compound layer, particularly preferably in a hole injecting and transporting layer, uniform surface emission without unevenness is possible, and high brightness is obtained for a long time. It can be stably obtained over a long period of time. 100 to 100,000 cd / m, depending on wavelength
A high brightness of about ² or more can be stably obtained. The maximum emission wavelength of the organic EL element of the present invention is 3
It is about 50 to 700 nm.

Further, the heat resistance and durability are high, and stable driving is possible even when the device current density is about 1 A / cm ² or more.

Furthermore, by using the compound for organic EL device of the present invention in the organic compound layer, the energy level is optimized, and the carriers are effectively blocked at the interface, so that stable carrier recombination and light emission can be achieved. Occur. In particular, by using the compound for organic EL device of the present invention in the hole injecting and transporting layer, a layer having a light emitting function in contact with the hole injecting and transporting layer (the light emitting layer serving also as the electron injecting and transporting layer is formed. , Or when the hole injecting and transporting layer is also a layer having a hole injecting and transporting function also serving as a light emitting layer, the difference in ionization potential Ip between this layer and the electron injecting and transporting layer in contact with this layer is optimized, and Since the carrier blocking effect is enhanced and the injection of carriers that are inferior or unstable in polarity is less likely to occur, the organic compound in each layer is less likely to be damaged, and carriers and excitons are lost in the carrier recombination region and the light emitting region. It is less likely to generate live points. As a result, stable light emission is obtained and the life is greatly improved.

By providing an organic compound layer in which the compound for organic EL device of the present invention is mixed with a compound having an electron injecting and transporting function, particularly as a light emitting layer, a hopping conduction path of carriers can be formed in the mixed layer. So
Each carrier injected into the mixed layer migrates in the more polar material. That is, holes move in the hole injecting / transporting substance and electrons move in the electron injecting / transporting substance, and carrier injection of the opposite polarity is less likely to occur, so that the organic compound is less likely to be damaged, and EL The life of the device is significantly improved.

Further, in the constitution in which the organic compound layer containing the compound for organic EL device of the present invention is doped with a fluorescent substance, by using the compound for organic EL device of the present invention in the hole injecting / transporting layer A layer having a light emitting function in contact with the hole injecting and transporting layer (the light emitting layer also serves as an electron injecting and transporting layer.
It includes an electron injecting and transporting layer. ) Or when the hole injecting and transporting layer is a layer having a hole injecting and transporting function also serving as a light emitting layer, the difference in ionization potential Ip between the layer and the electron injecting and transporting layer in contact with this layer is optimized, and the carrier blocking effect at the interface is obtained. Since the injection of carriers that are inferior or unstable in polarity is less likely to occur, the organic compound in each layer is less likely to be damaged, and deactivation points of carriers and excitons are generated in the carrier recombination region and the light emitting region. It gets harder. Further, particularly when rubrene is doped as a fluorescent substance, rubrene has a bibola transport property, and carrier recombination occurs in rubrene, so that the damage to the organic compound is further reduced accordingly.
In addition, since rubrene is present near the carrier recombination region, energy transfer from excitons to rubrene occurs, and non-radiative deactivation is reduced.As a result, stable light emission is obtained and life is greatly improved. To do.

[0064]

Specific Structure The specific structure of the present invention will be described in detail below.

The compound for organic EL device of the present invention (also referred to as "the compound of the present invention") is a tetraaryldiamine derivative represented by Chemical formula 16 (also referred to as "Compound of Chemical formula 16").

The chemical formula 16 will be explained. In the chemical formula 16, R _{1 to} R ₄ are each an aryl group, an alkyl group,
It represents an alkoxy group, an aryloxy group, an amino group or a halogen atom, and at least one of R _{1 to} R ₄ is an aryl group. r1 to r4 are 0 or 1 respectively
It is an integer of 5 and r1 to r4 cannot be 0 at the same time. Therefore, r1 + r2 + r3 + r4 is an integer of 1 or more, and is a number satisfying the condition that at least one aryl group exists. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5
And r6 are 0 or an integer of 1 to 4, respectively.

The aryl group represented by R _{1 to} R ₄ may be monocyclic or polycyclic, and includes condensed rings and ring assemblies. The total carbon number is preferably 6 to 20 and may have a substituent. Examples of the substituent in this case include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group and a halogen atom.

Specific examples of the aryl group represented by R _{1 to} R ₄ include phenyl group, (o-, m-, p-) tolyl group, pyrenyl group, perylenyl group, coronenyl group, naphthyl group and anthryl group. , A biphenylyl group, a phenylanthryl group, a tolylanthryl group, and the like. Particularly, a phenyl group is preferable, and an aryl group, particularly a phenyl group, has a 3-position (meta position with respect to the N-bond position) or 4-position. It is preferably (para position to the bonding position of N).

The alkyl group represented by R _{1 to} R ₄ may be linear or branched, preferably has 1 to 10 carbon atoms, and may have a substituent. . Examples of the substituent in this case include those similar to the aryl group.

Examples of the alkyl group represented by R _{1 to} R ₄ include a methyl group, an ethyl group, a (n-, i-) propyl group,
(N-, i-, s-, t-) butyl group etc. are mentioned.

The alkoxy group represented by R _{1 to} R ₄ is preferably an alkyl group having 1 to 6 carbon atoms, and specific examples thereof include a methoxy group, an ethoxy group and a t-butoxy group. The alkoxy group may be further substituted.

The aryloxy group represented by R _{1 to} R ₄ includes a phenoxy group, a 4-methylphenoxy group and a 4-methylphenoxy group.
(T-butyl) phenoxy group and the like.

As the amino group represented by R _{1 to} R ₄ ,
Although it may be unsubstituted or may have a substituent, those having a substituent are preferable, and specifically, dimethylamino group, diethylamino group, diphenylamino group, ditolylamino group, dibiphenylylamino group, N-phenyl. -N
-Tolylamino group, N-phenyl-N-naphthylamino group, N-phenyl-N-biphenylylamino group, N-phenyl-N-anthrylamino group, N-phenyl-N-
Examples thereof include a pyrenylamino group, a dinaphthylamino group, a dianthrylamino group, and a dipyrenylamino group.

Examples of the halogen atom represented by R _{1 to} R ₄ include chlorine atom and bromine atom.

At least one of R _{1 to} R ₄ is an aryl group, and it is particularly preferable that 2 to 4 aryl groups are present in one molecule as R _{1 to} R ₄ , and r _{1 to} r ₄
It is preferable that 2 to 4 of them are integers of 1 or more. In particular, 2 to 4 aryl groups are present in the molecule in total, more preferably 2 to 4 of r1 to r4 are 1, and r1 to r4 are 1, and R ₁ to R ₁ to
It is preferred that all of R ₄ are aryl groups. That is, there are a total of 2 to 4 aryl groups on the 4 benzene rings that may be substituted by R _{1 to} R ₄ in the molecule,
The benzene rings to which 2 to 4 aryl groups are bonded may be the same or different among the 4 benzene rings, but in particular, 2 to 4 aryl groups may be bonded to different benzene rings. preferable. Further, it is more preferable that at least two of them are bonded to the para position or the meta position with respect to the bonding position of N. In this case, it is preferable that at least one of the aryl groups is a phenyl group, that is, it is preferable that the aryl group and the benzene ring together form a 4- or 3-biphenylyl group with respect to the N atom. It is particularly preferred that 2 to 4 are 4- or 3-biphenylyl groups. The 4- or 3-biphenylyl group may be only one or may be a mixture of both. Further, as the aryl group other than the phenyl group, a (1-, 2-) naphthyl group, a (1-, 2-, 9-) anthryl group, a pyrenyl group, a perylenyl group, a coronenyl group and the like are particularly preferable, and other than the phenyl group. It is preferable that the aryl group of is also bonded to the para position or the meta position with respect to the bonding position of N. These aryl groups may also be mixed with the phenyl group.

In the chemical formula 16, the alkyl group, alkoxy group, amino group and halogen atom represented by R ₅ and R ₆ are the same as those mentioned in R _{1 to} R ₄ .

Both r5 and r6 are preferably 0, and the biphenylene group connecting the two arylamino groups is preferably unsubstituted.

When r1 to r4 are integers of 2 or more,
Each R _{1 to} R ₄ may be the same or different. Further, when r5 and r6 are integers of 2 or more, R _{5 s} and R _{6 s} may be the same or different.

Among the compounds of Chemical formula 16, the compounds represented by Chemical formulas 17 and 18 are preferable. First, the chemical formula 17 will be described. In the chemical formula 17, A _{1 to} A ₄ each represent a phenyl group bonded to the para position (4 position) or the meta position (3 position) with respect to the bonding position of N, and these are the same. However, it may be different. These phenyl groups may further have a substituent, and examples of the substituent in this case include the same substituents as those mentioned for the aryl group represented by R _{1 to} R ₄ . R _{7 to} R ₁₀
Each represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom,
These may be the same or different. Specific examples thereof include the same as those listed for R _{1 to} R _{4 in} Chemical formula 16.

R7 to r10 are each 0 or an integer of 1 to 4, and r7 to r10 are preferably 0.

Further, in Chemical formula 17, R ₅ , R ₆ , and r5
And r6 are synonymous with those of Chemical formula 16, and r5 = r6 =
It is preferably 0.

In Chemical formula 17, when r7 to r10 are each an integer of 2 or more, R _{7 to} R ₁₀ may be the same or different.

Next, the chemical formula 18 will be explained.
In, Ar is at the para-position or meta-position of the N-bonding position.
It represents an aryl group to be bonded. As the aryl group,
6 R₁ ~ R_Four The aryl group represented by
The same as those mentioned above, especially phenyl
Groups are preferred. In this case, the aryl group is further substituted
R may be present as such a substituent.₁ ~ R_Four of
By the way, the exemplified ones can be given. With substituents
Also, an amino group is preferable. However, if the amino group is
In some cases, it may be cyclized to form a heterocyclic group. Concrete
Specifically R₁ ~ R _Four Selected from the amino groups represented by
Can be Z₁ , Z₂ And Z₃Are each
Alkyl group, alkoxy group, aryl group, aryloxy
Group, amino group or halogen atom, which are the same
However, it may be different. As specific examples of these
Is R of₁ ~ R_Four The same as the ones listed in
Can be mentioned. However, Z₁ , Z₂ And Z
₃ At least one of these is the para position of the N binding position or
Represents an aryl group bonded to the meta position, and Ar, Z₁ ~
Z₃ Are all para positions relative to the N bonding position
Is not a phenyl group bonded to the meta position, and 4
2 to 3 of the benzene rings of each are in para or meta position
It is preferable to have one aryl group. Therefore,
Z₁ ~ Z₂ 1 or 2 of these are such allies
It is preferably a phenyl group. The aryl group includes (1
-, 2-) naphthyl group, (1-, 2-, 9-) antry
Group, pyrenyl group, perylenyl group, coronenyl group, etc. are also preferable.
However, a phenyl group is most preferable.

The aryl group represented by Z _{1 to} Z ₃ may have a substituent, and the substituent may be R ₁ to
The examples of R ₄ can be mentioned. Particularly, an amino group is preferable as the substituent. In particular,
It can be selected from the amino groups represented by R _{1 to} R ₄ . s1 to s3 are each 0 or an integer of 1 to 5, but they are never 0 at the same time, and the sum thereof is 1
It is an integer above the above. s1 to s3 are 0 or 1 respectively
And a combination in which one or two of s1 to s3 is 1 and the rest is 0 is preferable, and in this case, Z contained when s1 to s3 is 1
_{1 to} Z ₃ are preferably an aryl group bonded to the para position or the meta position with respect to the bonding position of N, particularly a phenyl group.

In Chemical formula 18, when s1 to s3 are integers of 2 or more, Z _{1 to} Z ₃ may be the same or different. In addition, R ₀ and r 0
Are each synonymous with R ₇ and r7 of Chemical formula 17, and R ₅ , R ₆ , r5 and r6 of Chemical formula 18 are respectively synonymous with those of Chemical formula 17, and the preferred ones are also the same.

Among the compounds of Chemical formula 17, Chemical formula 19 to Chemical formula 2
The compound represented by 4 is preferable. In each of Chemical formulas 19 to 24, R _{11 to} R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Specific examples thereof include the same as those listed for R _{1 to} R ₄ .

R11 to r14 are 0 or 1 to 5, respectively.
And it is preferable that r11 to r14 are 0 in any of Chemical formulas 19 to 24.

When r11 to r14 are each an integer of 2 or more, R _{11 to} R ₁₄ may be the same or different.

In each of Chemical formulas 19 to 24, R _{5 to} R
₁₀ and r5 to r10 have the same meanings as in Chemical formula 17, respectively, and the preferred ones are also the same.

On the other hand, among the compounds of Chemical formula 18,
The compound represented by Chemical formula 30 is preferable. Of each Ar ₁ to Ar ₆ shown in each of 25 of 30 represents an aryl group, of Ar ₁ and Ar ₂ of 25, the reduction 26 Ar ₁ and Ar
₃ , Ar ₁ and Ar ₂ and Ar ₃ of Chemical formula 27, Ar _{4 of} Chemical formula 28
And Ar ₅ ; Ar ₄ and Ar ₆ of Chemical formula 29; and Ar ₄ and Ar ₅ and Ar _{6 of} Chemical formula 30 may be the same or different. Specific examples of the aryl group include R ₁ of Chemical formula 16
The same as those described above for R ₄ to R ₄ can be mentioned, and a phenyl group is particularly preferable.

R ₁₅ of Chemical formulas 25 to 30, Chemical formulas 25 and 27,
R ₁₆ of Chemical formula 28, Chemical formula 30, Chemical formula 26, Chemical formula 27, Chemical formula 29, Chemical formula 3
R ₂₀ of 0 represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, respectively, and R ₁₅ and R ₁₆ of Chemical formula 25, Chemical formula 26, Chemical formula 26, Chemical formula 2
R ₁₅ and R ₂₀ in Chemical formula 9 and Chemical formula 27, and R ₁₅ and R ₁₆ and R _{20 in} Chemical formula 30 may be the same or different. Specific examples thereof include the same as those listed for R _{1 to} R _{4 in} Chemical formula 16.

R15 of Chemical formulas 25 to 30, Chemical formula 25, and Chemical formula 2
R16 of Chemical formula 7, Chemical formula 28, Chemical formula 30, Chemical formula 26, Chemical formula 27, Chemical formula 2
In formula 9 and formula 30, r20 is 0 or an integer of 1 to 4, and r15, r16 and r20 are preferably 0.

[0093] of 25, R ₁₉ of R _17, of 25 of 30 of R _18, reduction 26, of 29 of 28 each represent an alkyl group,
Represents an alkoxy group, an aryloxy group, an amino group or a halogen atom, wherein R ₁₇ and R ₁₈ in Chemical formula 25 and Chemical formula 2
R ₁₈ and R ₁₉ in Chemical Formula 6 and Chemical Formula 29 may be the same or different. Specific examples of these include R of Chemical formula 16
_The same as those mentioned in _{1 to} R ₄ can be mentioned.

R17 of Chemical formulas 25 and 28, Chemical formulas 25 to 30
R18 in Chemical formula 26, and r19 in Chemical formula 29 are 0 or 1 to 5
However, r17, r18 and r19 are preferably 0.

In the formulas 25 to 30, r15,
r16, if r20 is an integer of 2 or more, R ₁₅ to each other,
R _{16 s} and R _{20 s} may be the same or different, and when r ₁₇ , r ₁₈ and r ₁₉ are integers of 2 or more, R _{17 s} , R _{18 s} and R _{19 s} are the same or different. May be

In each of Chemical formulas 25 to 30, R ₅ , R _5
6 , r5 and r6 have the same meanings as those of chemical formula 16,
It is preferable that = r6 = 0.

Specific examples of the compound of Chemical formula 16 are shown below.
However, the present invention is not limited to this. In addition,
31, Chemical 37, Chemical 42, Chemical 47, Chemical 53, Chemical 58, Chemical 6
4, chemical formula 70, chemical formula 78, chemical formula 84, chemical formula 90, and chemical formula 95 are general formulas.
Chemical formulas 32 to 36, Chemical formulas 38 to 41, Chemical formulas 43 to 46,
Chemical formula 48 to 52, chemical formula 54 to 57, chemical formula 59 to 63, chemical formula 65
69, chemical formulas 71 to 77, chemical formulas 79 to 83, chemical formulas 85 to 89, chemical formulas
91 to 94, R to 96 to 100¹ Specific examples of combinations such as
Is shown. In this display, Ar₁ ~ Ar ₆ Excluding
And when all are H, they are shown as H, and there is a substituent
When the substituent is present, only the substituent is shown, and the other is H.
It means that there is.

[0098]

[Chemical 31]

[0099]

[Chemical 32]

[0100]

[Chemical 33]

[0101]

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[0102]

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[0103]

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[0104]

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[0105]

[Chemical 38]

[0106]

[Chemical Formula 39]

[0107]

[Chemical 40]

[0108]

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[0109]

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[0110]

[Chemical 43]

[0111]

[Chemical 44]

[0112]

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[0113]

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[0114]

[Chemical 47]

[0115]

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[0116]

[Chemical 49]

[0117]

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[0118]

[Chemical 51]

[0119]

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[0120]

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[0121]

[Chemical 54]

[0122]

[Chemical 55]

[0123]

[Chemical 56]

[0124]

[Chemical 57]

[0125]

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[0126]

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[0127]

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[0128]

[Chemical formula 61]

[0129]

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[0130]

[Chemical formula 63]

[0131]

[Chemical 64]

[0132]

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[0133]

[Chemical formula 66]

[0134]

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[0135]

[Chemical 68]

[0136]

[Chemical 69]

[0137]

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[0138]

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[0139]

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[0140]

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[0141]

[Chemical 74]

[0142]

[Chemical 75]

[0143]

[Chemical 76]

[0144]

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[0145]

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[0146]

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[0147]

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[0148]

[Chemical 81]

[0149]

[Chemical formula 82]

[0150]

[Chemical 83]

[0151]

[Chemical 84]

[0152]

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[0153]

[Chemical 86]

[0154]

[Chemical 87]

[0155]

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[0156]

[Chemical 89]

[0157]

[Chemical 90]

[0158]

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[0159]

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[0160]

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[0161]

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[0162]

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[0163]

[Chemical 96]

[0164]

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[0165]

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[0166]

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[0167]

[Chemical 100]

[0168]

[Chemical 101]

[0169]

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The compounds of the present invention are commercially available from Jean Piccard, Herr.
Chim. Acta., 7 , 789 (1924), JeanPiccard, J. Am. Ch
According to the method described in em. Soc., 48 , 2878 (1926) etc.
Alternatively, it can be synthesized in a similar manner. Specifically, a combination of a di (biphenyl) amine compound and a diiodobiphenyl compound or a combination of N, N′-diphenylbenzidine compound and an iodobiphenyl compound is heated in the presence of copper, depending on the target compound. (Ullmann reaction).

The compounds of the present invention were analyzed by mass spectrometry, infrared absorption spectrum (IR), ¹ H nuclear magnetic resonance spectrum (NM).
R) and the like.

These compounds of the present invention are 640 to 20
It has a molecular weight of about 00, has a high melting point of 190 to 300 ° C., exhibits a high glass transition temperature of 80 to 200 ° C., forms a transparent amorphous state stable even at room temperature or higher by ordinary vacuum deposition, etc., and is smooth. A good film is obtained, and it is maintained for a long period of time. It should be noted that some of the compounds of the present invention do not show a melting point and exhibit an amorphous state even at high temperatures. Therefore, a thin film can be formed by itself without using a binder resin.

The compounds of the present invention may be used alone or in combination of two or more.

The organic EL device of the present invention has at least one organic compound layer, and at least one organic compound layer contains the compound for organic EL device of the present invention. An example of the structure of the organic EL element of the present invention is shown in FIG. The organic EL device 1 shown in the figure has an anode 3, a hole injecting and transporting layer 4, a light emitting layer 5, an electron injecting and transporting layer 6, and a cathode 7 in this order on a substrate 2.

The light emitting layer has a function of injecting holes and electrons, a function of transporting them, and a function of generating excitons by recombination of holes and electrons. It is preferable to use a relatively electronically neutral compound in the light emitting layer.
The hole injecting and transporting layer has a function of facilitating injection of holes from the anode, a function of transporting holes and a function of hindering electrons, and the electron injecting and transporting layer facilitates injection of electrons from the cathode. These layers have a function of transporting electrons, a function of transporting electrons, and a function of blocking holes, and these layers increase and confine holes and electrons injected into the light emitting layer, optimize the recombination region, and emit light. Improve efficiency. The hole injecting and transporting layer and the electron injecting and transporting layer consider the height of each of the hole injecting, hole transporting, electron injecting, and electron transporting functions of the compound used for the light emitting layer,
It is provided as needed. For example, when the compound used for the light emitting layer has a high hole injecting / transporting function or an electron injecting / transporting function, the light emitting layer is not provided with the hole injecting / transporting layer or the electron injecting / transporting layer, and the light emitting layer is the hole injecting / transporting layer or the electron injecting / transporting layer. It can be configured to also serve as a transport layer. In some cases, neither the hole injecting / transporting layer nor the electron injecting / transporting layer may be provided. In addition, the hole injecting and transporting layer and the electron injecting and transporting layer may be separately provided in the layer having the injection function and the layer having the transport function.

The thickness of the light emitting layer, the thickness of the hole injecting and transporting layer and the thickness of the electron injecting and transporting layer are not particularly limited and may vary depending on the forming method, but are usually about 5 to 1000 nm, particularly 1 nm.
It is preferably 0 to 200 nm.

The thickness of the hole injecting and transporting layer and the thickness of the electron injecting and transporting layer may be the same as the thickness of the light emitting layer or about 1/10 to 10 times, although it depends on the design of the recombination / light emitting region. . When the electron injection layer and the electron injection layer are separated from the transport layer, it is preferable that the injection layer has a thickness of 1 nm or more and the transport layer has a thickness of 20 nm or more. At this time, the upper limit of the thickness of the injection layer and the transport layer is usually about 100 nm in the injection layer and 100 in the transport layer.
It is about 0 nm. Such a film thickness is the same when two injecting and transporting layers are provided.

Also, recombination can be achieved by controlling the film thickness while considering the carrier mobility and carrier density (determined by the ionization potential and electron affinity) of the light emitting layer, electron injecting and transporting layer and hole injecting and transporting layer to be combined. It is possible to freely design the area and the light emitting area, and it is possible to design the light emitting color, control the light emitting luminance and the light emitting spectrum by the interference effect of both electrodes, and control the spatial distribution of light emission.

The compound of the present invention can be applied to both a light emitting layer and a hole injecting / transporting layer, but since it has a good hole injecting / transporting property, it is preferably used in the hole injecting / transporting layer.

The case where the compound of the present invention is used in the hole injecting and transporting layer will be described. The hole injecting and transporting layer may be formed by vapor-depositing the compound of the present invention or by dispersing it in a resin binder and coating it. Particularly, good vapor deposition can be obtained by vapor deposition.

Various organic compounds used in ordinary organic EL devices, for example, JP-A-63-295695.
Japanese Patent Laid-Open No. Hei 2-191694, Japanese Patent Laid-Open No. 3-7
Various organic compounds described in Japanese Patent Publication No. 92, etc. can be used in combination with the hole injecting and transporting layer. For example, an aromatic tertiary amine other than the compound of the present invention, a hydrazone derivative,
Carbazole derivative, triazole derivative, imidazole derivative, oxadiazole derivative having amino group,
Polythiophene and the like may be laminated or mixed with the compound of the present invention.

When the hole injecting and transporting layer is separately formed into the hole injecting layer and the hole transporting layer, preferable combinations can be selected and used from the compounds for the hole injecting and transporting layer. At this time, it is preferable to stack layers of a compound having a small ionization potential in order from the anode (ITO or the like) side. Further, it is preferable to use a compound having a good thin film property on the surface of the anode. This stacking order is the same when two or more hole injecting and transporting layers are provided. By adopting such a stacking order, the driving voltage is lowered, and it is possible to prevent the occurrence of current leakage and the generation / growth of dark spots. In addition, since vapor deposition is used to form a device, a thin film of about 1 to 10 nm can be made uniform and pinhole-free, so that the hole injection layer has a small ionization potential and absorption in the visible region. Even if such a compound is used, it is possible to prevent a decrease in efficiency due to a change in the color tone of the emission color or reabsorption.

Polythiophene is preferable as the organic compound used in the hole injecting / transporting layer containing the compound of the present invention as a main component, and polythiophene is used as the positive hole injecting / transporting layer having a good thin film property. From the viewpoint of ionization potential, it is more preferable to stack the compound of the present invention as a hole transport layer or a second hole injection transport layer after vapor deposition on the above.

The polythiophene preferably used in the present invention is a polymer having a structural unit represented by Chemical formula 103 (hereinafter, also referred to as "polymer A"), a structural unit represented by Chemical formula 103 and a chemical unit represented by Chemical formula 104. And a polymer having a structural unit (hereinafter, also referred to as “copolymer B”) and a polymer represented by Chemical Formula 105 (hereinafter, “polymer C”).

[0185]

Embedded image

[0186]

[Chemical 104]

[0187]

Embedded image

First, the polymer A will be described. The polymer A has a structural unit represented by Chemical Formula 103 and is represented by, for example, Chemical Formula 106.

[0189]

[Chemical formula 106]

As for chemical formulas 103 and 106, R ₃₁
And R ₃₂ each represent a hydrogen atom, an aromatic hydrocarbon group or an aliphatic hydrocarbon group, which may be the same or different.

The aromatic hydrocarbon group represented by R ₃₁ and R ₃₂ may be unsubstituted or may have a substituent, and preferably has 6 to 15 carbon atoms. When it has a substituent, examples of the substituent include an alkyl group, an alkoxy group, an amino group and a cyano group. Specific examples of the aromatic hydrocarbon group include a phenyl group, a tolyl group, a methoxyphenyl group, a biphenyl group and a naphthyl group.

Examples of the aliphatic hydrocarbon group represented by R ₃₁ and R ₃₂ include an alkyl group and a cycloalkyl group, which may be unsubstituted or may have a substituent. Of these, those having 1 to 6 carbon atoms are preferable, and specific examples thereof include a methyl group, an ethyl group, an i-propyl group, and a t-butyl group.

As R ₃₁ and R ₃₂ , a hydrogen atom and an aromatic hydrocarbon group are preferable, and a hydrogen atom is particularly preferable.

Average Polymerization Degree of Polymer A in Layer (Chemical Formula 1
M) of 06 is 4 to 100, preferably 5 to 40, more preferably 5 to 20. In this case, a polymer (homopolymer) in which the repeating unit shown in Chemical formula 103 is completely the same
Alternatively, the compound may be a copolymer in which the combination of R ₃₁ and R ₃₂ in Chemical formula 103 is different. As the copolymer, a random copolymer,
It may be an alternating copolymer, a block copolymer, or the like.

The weight average molecular weight of the polymer A in the layer is about 300 to 10,000.

The terminal groups (X ₁ and X _{2 in} Chemical Formula 106) of the polymer A are hydrogen atoms, halogen atoms such as chlorine, bromine and iodine. This end group is generally introduced depending on the starting material in the synthesis of polymer A. Furthermore, other substituents can be introduced at the final stage of the polymerization reaction.

The polymer A is preferably composed only of the structural unit represented by Chemical formula 103, but may contain other monomer components as long as it is 10 mol% or less.

A specific example of the polymer A is shown in Chemical formula 107. Chemical 1
In No. 07, a combination of R ₃₁ and R _{32 in} Chemical formula 103 to Chemical formula 106 is shown.

[0199]

[Chemical formula 107]

Next, the copolymer B will be described. The copolymer B has a structural unit of chemical formula 103 and a structural unit of chemical formula 104, and is, for example, one shown in chemical formula 108.

[0201]

[Chemical 108]

The chemical formula 103 is the same as that of the polymer A. Therefore, R ₃₁ and R ₃₂ in Chemical formula 108 are the same as those in Chemical formula 103.

With regard to the chemical formula 104, R ₃₃ and R ₃₄ each represent a hydrogen atom, an aromatic hydrocarbon group or an aliphatic hydrocarbon group, which may be the same or different.

An aromatic hydrocarbon group represented by R ₃₃ and R ₃₄ ,
Specific examples of the aliphatic hydrocarbon group are the same as those listed for R ₃₁ and R _{32 in} Chemical formula 103. Further, the preferable ones of R ₃₃ and R ₃₄ are the same as those of R ₃₁ and R ₃₂ . Further, R ₃₃ and R ₃₄ may be bonded to each other to form a ring and condensed with a thiophene ring. Examples of the condensed ring in this case include a benzene ring. This R ₃₃ ,
For R ₃₄ is the same in the reduction 108.

The average degree of polymerization of copolymer B in the layer (v + w in Chemical Formula 108) is 4 to 1 as in the case of polymer A.
00, preferably 5 to 40, more preferably 5 to 20
Is. Further, the ratio of the structural unit of Chemical formula 103 to the structural unit of Chemical formula 104 is about 10/1 to 1/10 in molar ratio of the structural unit of Chemical formula 103 / the structural unit of Chemical formula 104.

The weight average molecular weight of the copolymer B in the layer is about 300 to 10,000.

The terminal groups of the copolymer B (X ₁ and X ₂ in Chemical Formula 108) are the same as those of the polymer A,
In general, it depends on the starting materials used in the synthesis of copolymer B and the ratio thereof.

The copolymer B is the same as the polymer A,
It is preferably composed of the structural unit of Chemical formula 103 and the structural unit of Chemical formula 104, but other monomer components may be contained as long as they are 10 mol% or less. Further, the copolymer B is
It may be a random copolymer, an alternating copolymer, a block copolymer, or the like, and the structural formula of Chemical formula 108 includes such a structure. Furthermore,
The structural units 04 may be the same or different.

A specific example of the copolymer B is shown in Chemical formula 109. In chemical formula 109, a combination of R ₃₁ and R _{32 in} chemical formula 103, a combination of R ₃₃ and R _{34 in} chemical formula 104, that is, R ₃₁ and R ₃₂ in chemical formula 108,
The combination of R ₃₃ and R ₃₄ is shown.

[0210]

[Chemical 109]

Further, the polymer C of Chemical formula 105 will be described. As for the chemical formula 105, R ₃₃ and R ₃₄ are the chemical formula 1.
It has the same meaning as that of No. 04, and the preferred ones are also similar.

X ₁ and X _{2, which} may be the same or different, each is a hydrogen atom or a halogen atom such as chlorine, bromine or iodine, like the terminal groups of the polymer A and the copolymer B. . X ₁ and X ₂ depend on the starting materials in the synthesis of polymer C.

N represents the average degree of polymerization, and is 4 to 100, preferably 5 to 4 as in the case of the polymer A and the copolymer B in the layer.
It is 0, more preferably 5 to 20. In this case, R ₃₃
The combination of R ₃₄ and R ₃₄ may be the same polymer (homopolymer), or the combination of R ₃₃ and R ₃₄ may be different copolymers. The copolymer may be a random copolymer, an alternating copolymer, a block copolymer, or the like.

The weight average molecular weight of the polymer C in the layer is about 300 to 10,000.

The polymer C preferably has the structure shown in Chemical formula 105, but like the polymers A and B, if it is 10 mol% or less, it contains other monomer components. May be.

Specific examples of the polymer C are shown in Chemical formulas 110 and 111. The chemical formula 110 is the same as the chemical formula 105, and the chemical formula 111 shows the combination of R ₃₃ and R ₃₄ of the chemical formula 110.

[0219]

[Chemical 110]

[0218]

[Chemical 111]

In the present invention, as the polythiophene, it is particularly preferable to use the polymer C among the above polymers.

The polythiophene may be used alone or in combination of two or more.

The melting point of polythiophene used in the present invention is 3
It has a temperature of not lower than 00 ° C. or has no melting point, and a high-quality film in an amorphous state or a microcrystalline state can be obtained by vacuum vapor deposition.

As described above, when the compound of the present invention is used in the hole injecting and transporting layer, the light emitting layer contains a fluorescent substance which is a compound having a light emitting function. Examples of the fluorescent substance include at least one selected from compounds such as those disclosed in JP-A-63-264692, such as quinacridone, rubrene, and styryl dyes. Other metal complex dyes such as tris (8-quinolinolato) aluminum, tetraphenylbutadiene, anthracene, perylene, coronene, 12-
Examples include phthaloperinone derivatives. These organic phosphors are vapor-deposited or dispersed in a resin binder for coating to form a light-emitting layer with a predetermined thickness.

The electron injecting and transporting layer includes an organometallic complex such as tris (8-quinolinolato) aluminum, an oxadiazole derivative, a perylene derivative, a pyridine derivative, a pyrimidine derivative, a quinoline derivative, a quinoxaline derivative, a diphenylquinone derivative, and a nitro-substituted fluorene. A derivative or the like can be used. The electron injecting and transporting layer may also serve as the light emitting layer. In such a case, tris (8-
It is also preferable to use quinolinolato) aluminum or the like. The electron injecting and transporting layer may be formed by vapor deposition or the like as in the hole injecting and transporting layer and the light emitting layer.

When the electron injecting and transporting layer is separately formed into the electron injecting layer and the electron transporting layer, preferable combinations can be selected and used from the compounds for the electron injecting and transporting layer. At this time, it is preferable to stack the compound layers having a large electron affinity value in this order from the cathode side. The stacking order is the same when two or more electron injecting and transporting layers are provided.

Further, the organic compound layer may contain a singlet oxygen quencher.

Examples of such a quencher include rubrene, nickel complex, diphenylisobenzofuran and tertiary amine. Of these, rubrene is particularly preferable. When used in combination with the compound of the present invention, the content of such a quencher is preferably 10 mol% or less of the compound of the present invention.

In the present invention, it is preferable to dope the organic compound layer with rubrene.

Doping may be performed on the entire organic compound layer,
Preferably, the entire area of the hole injecting and transporting layer is used. In particular, it is considered that it is preferable that rubrene exists at the carrier recombination region, the light emitting region and its vicinity, for example, at the contact interface with the organic compound layer of the hole injecting and transporting layer. As a half region of the hole injecting and transporting layer which is in contact with the light emitting layer (including the case of also serving as the electron injecting and transporting layer) or the electron injecting and transporting layer (when the hole injecting and transporting layer also serves as the light emitting layer) However, it is usually the entire area of the hole injecting and transporting layer. In some cases, the entire hole injecting and transporting layer or the hole injecting and transporting layer,
It is also possible to form a half region on the side of the light emitting layer or the electron injecting and transporting layer which is in contact with this, and a half region of the light emitting layer or the electron injecting and transporting layer on the side of the hole injecting and transporting layer. In particular, in the hole injecting and transporting layer, the combined use of the compound of the present invention and rubrene is preferable.

The doping concentration of rubrene is not preferably high because rubrene causes concentration quenching, and is preferably 0.1 to 50 wt%, more preferably 0.1 to 30 wt% with respect to the entire doped layer. , Especially 0.1
20 wt% is preferable.

In the present invention, in addition to rubrene, another fluorescent substance may be doped.

In the present invention, a mixed layer containing a mixture of both compounds is provided between the layer containing the compound of the present invention and the layer containing the compound having another function, particularly as a light emitting layer. preferable. Further, in order to increase the emission intensity, the mixed layer may be doped with a compound having a light emitting function (fluorescent substance).

In particular, since the compound of the present invention is a compound having a hole injecting and transporting function, a layer containing a mixture with a compound having an electron injecting and transporting function (including a compound having a light emitting function) emits light. It is preferably provided as a layer. The compound having an electron injecting and transporting function to be used for this mixing can be selected from the above compounds for electron injecting and transporting and used. Specifically, it is preferable to use tris (8-quinolinolato) aluminum or the like.

Further, in the mixed layer, the compounds having a hole and electron injecting and transporting function may be used alone or in combination of two or more, and as the compound having a hole injecting and transporting function, the present invention may be used. In addition to the above compound, it can be selected and used from the above compounds for hole injecting and transporting.

In particular, a hole injecting and transporting layer using the compound of the present invention is laminated on the hole injecting and transporting layer using polythiophene, and the hole injecting and transporting layer and the electron injecting and transporting layer are interposed between the layers. It is preferable to interpose a mixed layer of both as a light emitting layer.

The mixing ratio in this case depends on the carrier mobility, but the compound of the present invention is 30 to 70 wt% with respect to the entire mixed layer.
%, Further 40 to 60 wt%, especially about 50 wt% (therefore, the weight ratio of the compound of the present invention / the compound having an electron injecting and transporting function is usually 30/70 to 70/30, further 40/60 to 60). / 40, and especially about 50/50).

Further, the thickness of the mixed layer is preferably less than the thickness of the organic compound layer from the thickness corresponding to one molecular layer, specifically 1 to 85 nm,
Further, it is preferably 5 to 60 nm, and particularly preferably 5 to 50 nm.

As a method for forming the mixed layer, co-evaporation in which evaporation is performed from different evaporation sources is preferable, but when vapor pressures (evaporation temperatures) are similar or very close, they are mixed in advance in the same evaporation board. It can also be vapor-deposited. Although it is preferable that the compounds are uniformly mixed in the mixed layer, the compounds may exist in an island shape in some cases.

The mixed layer can also be used for an organic compound layer other than the light emitting layer. However, it is preferable to form a part of the organic compound layer existing in the device, and if all the organic compound layers are mixed layers, it may be difficult to obtain high-luminance uniform light emission.

The compound of the present invention is preferably used in the hole injecting and transporting layer, and the ionization potential Ip with the light emitting layer (which also serves as the electron injecting and transporting layer) provided in contact with the hole injecting and transporting layer. Is preferably 0.25 eV or more, and particularly preferably 0.25 to 0.40 eV.

The difference in the above-mentioned ionization potential Ip is
When the layer containing the compound of the present invention is a layer having a hole injecting and transporting function and also functions as a light emitting layer,
Since the layer in contact with this layer is an electron injecting and transporting layer, the difference from this layer is set.

The absolute value of the ionization potential Ip of the compound of the present invention is about 5.0 to 5.4 eV.

The above-mentioned ionization potential Ip is determined by the low energy electron spectrometer "Model AC-" according to the description of Shirahashi, Isobe, Uda, Electronic Materials, 123 (1985).
1 ”(manufactured by Riken Keiki Co., Ltd.) and a value obtained by using a sample in which a 10-200 nm-thick single-layer deposited film is formed on a substrate having an ITO transparent electrode, a slide glass, or the like.

The above-mentioned low-energy electron spectrometer is shown in FIG.
It has the configuration shown in.

As shown in FIG. 2, the spectroscopic device 10 comprises an ultraviolet lamp 11, a monochromator 12, a detector 13, a low-energy electron counting device 14, a control device 15, a calculation display device 16 and an XY stage 17. And X-
The sample S is placed on the Y stage for measurement.

A deuterium lamp is used as the ultraviolet lamp 11, and the light emitted from this lamp is dispersed by the monochromator 12 into an arbitrary wavelength of 200 to 360 nm, and the sample S surface is irradiated with the light. Light of 200 to 360 nm is E = hν = h
(C / λ) (E: energy, h: Planck's constant, ν:
When converted into energy using the formula of frequency, λ: wavelength), each becomes 6.2 to 3.4 eV. When this light is swept from the lower excitation energy to the higher excitation energy, electron emission due to the photoelectric effect starts at a certain energy. This energy is a value generally called a photoelectric work function. The photoelectrons emitted in this way are detected by the detector 1.
3 and the low-energy electron counter 14 to perform counting such as bagland correction and correction of counting down during dead time, and then excitation energy / emission electron amount characteristics (basic characteristics) as shown in FIG. Calculation display device 16
On the display of.

As shown in the basic characteristics, this photoelectron emission rate
Relationship: (C ount P er S econd CPS) and the excitation energy (eV) is the vertical axis n-th power of the light emission rate and (CPS) ^n, when the horizontal axis and the excitation energy can be expressed in a linear relationship . Here, the value of n is usually 1/2.

The control unit 15 is the monochromator 12
Wavelength control, sample position control by the XY stage 17, and counting control of the low energy electron coefficient device 14.

Therefore, in the present invention, the photoelectric work function obtained from FIG. 3 is used as the ionization potential Ip.

When the layer containing the compound of the present invention further contains another compound and the compound of the present invention is the main component (usually 50 wt% or more), The value of the ionization potential Ip obtained from the monolayer film of the compound of the invention is calculated as the ionization potential Ip of this layer.
Shall be considered. Also, when two or more compounds are contained in a layer to be compared with a layer containing the compound of the present invention,
The value of the ionization potential Ip obtained from the monolayer film of the compound as the main component (usually the content of 50 wt% or more) shall be regarded as the ionization potential Ip of this layer.

The absolute value of the ionization potential Ip is smaller in the monolayer film of the compound of the present invention than in the monolayer film of the compound to be compared and controlled.

It should be noted that such a concept of the ionization potential is not applied to the structure in which the mixed layer is interposed.

For the cathode, it is preferable to use a material having a low work function, for example, Li, Na, Mg, Al, Ag, In or an alloy containing at least one of these. Further, the cathode preferably has fine crystal grains, and particularly preferably is in an amorphous state. The thickness of the cathode is 10
It is preferably about 1000 nm.

At least one of the electrodes must be transparent or semi-transparent in order to make the organic EL device emit surface light. Since the cathode material is limited as described above, the transmittance of emitted light is preferable. It is preferable to determine the material and thickness of the anode so that the ratio is 80% or more. Specifically, for example, ITO, SnO ₂ , Ni, Au, Pt, P
It is preferable to use d, a polypyrrole doped with a dopant, or the like for the anode. The thickness of the anode is 10-50.
It is preferably about 0 nm. In addition, a low drive voltage is required to improve the reliability of the device,
A preferable example is ITO of 10 to 30 Ω / □.

The substrate material is not particularly limited, but in the illustrated example, a transparent or translucent material such as glass or resin is used in order to take out the emitted light from the substrate side. Further, the substrate may be provided with a color filter film, a color conversion film containing a fluorescent substance, or a dielectric reflection film to control the emission color.

Note that when an opaque material is used for the substrate, the stacking order shown in FIG. 1 may be reversed.

Next, a method for manufacturing the organic EL device of the present invention will be described.

The cathode and anode are preferably formed by vapor phase growth method such as vapor deposition method and sputtering method.

For forming the hole injecting / transporting layer, the light emitting layer and the electron injecting / transporting layer, it is preferable to use the vacuum deposition method because a uniform thin film can be formed. When the vacuum deposition method is used, a homogeneous thin film having an amorphous state or a crystal grain size of 0.1 μm or less (usually, the lower limit is about 0.001 μm) can be obtained. If the crystal grain size exceeds 0.1 μm, non-uniform light emission occurs, the drive voltage of the device must be increased, and the charge injection efficiency is significantly reduced.

The conditions of vacuum vapor deposition are not particularly limited, but 1
The degree of vacuum is 0 ^-3 Pa or less, and the deposition rate is 0.1 to 1 nm / se.
It is preferably about c. Moreover, it is preferable to form each layer continuously in a vacuum. If they are continuously formed in a vacuum, it is possible to prevent impurities from adsorbing to the interface of each layer, so that high characteristics can be obtained. In addition, the drive voltage of the element can be lowered.

When a vacuum vapor deposition method is used to form each of these layers, when a plurality of compounds are contained in one layer, it is preferable that the boats containing the compounds are individually temperature-controlled for co-evaporation, but they are mixed in advance. You may vapor-deposit after that.
In addition to this, a solution coating method (spin coating, dip, cast, etc.) Langmuir-Blodgett (LB) method or the like can also be used. In the solution coating method, the compound of the present invention may be dispersed in a matrix substance such as a polymer.

The organic EL device of the present invention is usually used as a DC drive type EL device, but it can also be AC drive or pulse drive. The applied voltage is usually 2 to 20.
It is about V.

The compound of the present invention can be applied as an organic semiconductor material having a donor property to photoelectric conversion elements other than organic EL elements, for example, photocells and photosensors.
Furthermore, it is also useful as a thermochromic material that utilizes the transition between an amorphous state and crystals.

[0263]

EXAMPLES Hereinafter, the present invention will be described in more detail by showing specific examples of the present invention together with comparative examples.

Example 1 Synthesis of N, N, N ′, N′-tetra (3-biphenylyl) benzidine (Compound No. I-1) m-nitrobiphenyl 25 was added to a 2000 ml atmospheric pressure hydrogenation device.
0 g (1.26 mol), 5% Pd-C 12.5 g and ethanol 1250 ml were charged, and the theoretical amount of hydrogen gas was absorbed at room temperature. The catalyst was removed by filtration, and the filtrate was evaporated to give 212 g of m-aminobiphenyl (yield 99.9%). In addition, 254 m-nitrobiphenyl
Another 1 on the same scale except g (1.28 mol)
Batch reaction was performed to obtain 215 g of m-aminobiphenyl (yield 99.7%).

Concentrated hydrochloric acid 775 was added to a 10,000 ml reaction vessel.
ml, water 775 ml, and ice 775 g were charged, and 125 g (0.740 mol) of m-aminobiphenyl was added and suspended. 50.3g of sodium nitrite below 0 ℃
A (750 ml) aqueous solution of (0.816 mol) was added dropwise for 30 minutes, and then stirred at the same temperature for 50 minutes. 185 g of potassium iodide was added to the obtained diazonium salt aqueous solution at 0 ° C or lower.
A 1250 ml (1.12 mol) aqueous solution was added dropwise for 1 hour. After dropping, the mixture was stirred for 1 hour at the same temperature, returned to room temperature and stirred for 2 hours.

The reaction solution was extracted with ethyl acetate, the organic layer was washed with water, dried (magnesium sulfate) and the solvent was distilled off to obtain crude crystals. The mixture was further reacted on the same scale for one batch, and the obtained crude crystals were combined and purified by a silica gel column with n-hexane to obtain 297 g of m-iodobiphenyl (71.7% yield for the two batches combined). .

In a 2000 ml reaction vessel, 140 g (0.828 mol) of m-aminobiphenyl, 232 g (0.829 mol) of m-iodobiphenyl, and 63.1 of potassium carbonate.
g (0.457 mol), 13.9 g of copper powder and 800 ml of nitrobenzene were charged, and the mixture was heated under reflux for 32 hours under Ar flow. After completion of the reaction, insoluble matter was removed by filtration, and the filtrate was evaporated. The obtained residue is n-hexane / toluene = 4
Silica gel column purification with 1/1, and 44.5 g of di (3
-Biphenyl) amine (high purity product) was obtained (yield 16.
7%).

In a 500 ml reaction vessel, di (3-biphenyl) amine 44.5 g (0.139 mol), 4,4'-
27.6 g (0.0680 mol) of diiodobiphenyl,
Potassium carbonate 34.3 g (0.249 mol), copper powder 2.
3 g and 180 ml of nitrobenzene were charged, and the mixture was heated under reflux for 24 hours under Ar stream. After completion of the reaction, insoluble matter was removed by filtration, and the filtrate was evaporated. The obtained residue is purified by a silica gel column with n-hexane / toluene = 3/1,
30 g of primary purified N, N, N ', N'-tetra (3-biphenylyl) benzidine was obtained (yield 55.7%). This was recrystallized and purified with toluene to obtain 6.0 g of a 99.58% pure product and 5.0 g of a 99.23% pure product (yield 2
0.4%). Furthermore, sublimation purification is performed to obtain a purity of 99.99.
% 8.0 g was obtained.

Mass spectrum: m / e 792 (M ⁺ ) Infrared absorption spectrum (IR): FIG. 4 NMR spectrum: FIG. 5 Differential scanning calorimetry (DSC): Melting point 207.4 ° C., glass transition temperature 95.8 ° C.

Example 2 Synthesis of N, N, N ′, N′-tetra (4-biphenylyl) benzidine (Compound No. II-1) 4-aminobiphenyl 72.5 g (0.429 mol)
), 4-iodobiphenyl 120 g (0.429 mol
), Potassium carbonate 32.6 g (0.236 mol), copper 6.8 g (0.107 mol), nitrobenzene 430 ml
Was charged and reacted overnight at 210 ° C. Allow to cool after reaction,
After removing copper salts by filtration under reduced pressure and washing with chloroform, the solvent of the filtrate was distilled off under reduced pressure. 500 ml of methanol to the residue
After cooling, the precipitated crystals were collected by filtration. 49 g of crystals obtained
Was dissolved in 250 ml of dimethylformamide (DMF) by heating and cooled with water, by-product tribiphenylamine was precipitated, so it was filtered off. The filtrate was poured into 1000 ml of water and the precipitated crystals were collected by filtration and washed with water. , Washed with methanol.

35 g of the obtained water-containing crystals was recrystallized from 750 ml of toluene to give yellowish green scaly crystals of di (4-).
Biphenyl) amine was obtained. The mother liquor was concentrated to collect secondary crystals. The yield was 19 g (yield 13.8%).

15 g of di (4-biphenyl) amine (0.
0467 mol), 4,4'-diiodobiphenyl 9.5
g (0.0234 mol), potassium carbonate 9.7 g (0.
0702 mol), 0.74 g of copper (0.0117 mol),
76 ml of nitrobenzene was charged and reacted at 220 ° C. for 2 days and nights. After the reaction, 750 ml of DMF was added, and the mixture was filtered while hot to remove copper salts, the filtrate was cooled, and the precipitated crystals were collected by filtration. 25 g of the obtained water-containing crystal was mixed with 100 times amount of toluene.
By repeating recrystallization twice, N, which is a target product of light yellow crystals,
N, N ', N'-tetra (4-biphenylyl) benzidine was obtained (yield 9 g, yield 48.6%). Further, sublimation purification was performed to obtain a product with a purity of 99.99%.

Mass spectrum: m / e 792 (M ⁺ ) Infrared absorption spectrum (IR): FIG. 6 NMR spectrum: FIG. 7 Differential scanning calorimetry (DSC): Melting point 267.7 ° C., glass transition temperature 131.8 ° C.

<Example 3> Synthesis of N, N'-diphenyl-N, N'-di (3-biphenylyl) benzidine (Compound No. VII-1) In a 10000 ml reaction vessel, concentrated hydrochloric acid (155 ml) and water (155 ml) were added.
g, ice 155g, m-aminobiphenyl 25g
(0.148 mol) was added and suspended. A 150 ml aqueous solution of 11.3 g (0.164 mol) of sodium nitrite was added dropwise thereto at 0 ° C. or lower for 30 minutes, and then stirred at the same temperature for 50 minutes. To the resulting diazonium salt aqueous solution, 0 ° C
25 g of potassium iodide 37 g (0.223 mol)
A 0 ml aqueous solution was added dropwise for 1 hour. After dropping, the mixture was stirred for 1 hour at the same temperature, returned to room temperature and stirred for 2 hours. The reaction solution was extracted with ethyl acetate, the organic layer was washed with water, dried (magnesium sulfate),
The solvent was distilled off to obtain crude crystals.

This was purified by a silica gel column with n-hexane to obtain 28 g of m-iodobiphenyl.

In a 300 ml reaction vessel, 10 g (0.0298 mol) of N, N'-diphenylbenzidine, 25 g (0.0893 mol) of m-iodobiphenyl, 12.3 g (0.0891 mol) of potassium carbonate, 2.6 g of copper powder, 150 ml of nitrobenzene was charged and heated under reflux for 24 hours under Ar flow. After completion of the reaction, insoluble matter was removed by filtration, and the filtrate was evaporated. The obtained residue was purified by a silica gel column with n-hexane / ethyl acetate = 5/1 to obtain 15 g of primary purified N, N′-diphenyl-N, N′-di (3-biphenylyl) benzidine. Rate 78.8%). This was recrystallized and purified with toluene, and 10.6 g of purity 9
A 9.9% product was obtained (yield 55.6%). Further, sublimation purification was performed to obtain a product with a purity of 99.99%.

Mass spectrum: m / e 640 (M ⁺ ) Infrared absorption spectrum (IR): FIG. 8 NMR spectrum: FIG. 9 Differential scanning calorimetry (DSC): melting point 189.8 ° C., glass transition temperature 83.6 ° C.

<Example 4> N, N'-diphenyl-N, N'-bis [-4 '-(N
Synthesis of -phenyl-N-3-methylphenylamino) biphenyl-4-yl] benzidine (Compound No. X-10) 33.6 g (0.10 mol), m of N, N'-diphenylbenzidine in a 500 ml reaction vessel. -Iodotoluene 2
5.0 g (0.11 mol), potassium carbonate 27.6 g
(0.2 mol), copper powder 2.6 g, nitrobenzene 200
ml was charged and the mixture was heated under reflux for 24 hours under Ar flow. After completion of the reaction, insoluble matter was removed by filtration, and the filtrate was evaporated. The obtained residue was subjected to silica gel column purification twice with n-hexane / toluene = 1/2 to give 28.10 g of N, N'-diphenyl-N [-4- (N-phenyl-N.
-3-Methylphenylamino) biphenyl-4-yl]
Benzidine was obtained (yield 42%).

8.1 g (0.02 mol) of 4,4'-diiodobiphenyl and N, N'-diphenyl-N [-4- (N-phenyl-N-3-methylphenylamino) were placed in a 500 ml reaction vessel. Biphenyl-4-yl] benzidine 2
8.1 g (0.02 mol), potassium carbonate 11.04 g
(0.08mol), copper powder 1.0g, nitrobenzene 10
0 ml was charged, and the mixture was heated under reflux for 24 hours under Ar stream.
After completion of the reaction, insoluble matter was removed by filtration, and the filtrate was evaporated. The obtained residue was subjected to silica gel column purification twice with n-hexane / toluene = 2/1, and 11.62 g of high-purity N, N'-diphenyl-N, N'-bis [-4 '
-(N-phenyl-N-3-methylphenylamino) biphenyl-4-yl] benzidine was obtained (yield 58
%). This was recrystallized and purified with a mixed solvent of hexane and toluene to obtain 7.3 g of a light yellow transparent amorphous solid having a purity of 99.9%.

Mass spectrometry: m / e 1002 (M ⁺ ) Infrared absorption spectrum (IR): FIG. 10 NMR spectrum: FIG. 11 Differential scanning calorimetry (DSC): No melting point was observed (from the initial state, it was amorphous). there were). Glass transition temperature 132 ℃

<Example 5> N, N'-diphenyl-N, N'-bis [-4'-
(N, N-di-3-biphenylylamino) biphenyl-
Synthesis of 4-yl] benzidine (Compound No. X-3) Di (3-biphenylyl) amine 1 in a 300 ml reaction vessel.
6.1 g (0.050 mol), 4,4'-diiodobiphenyl 20.3 g (0.050 mol), potassium carbonate 1
3.8 g (0.10 mol), 1.0 g of copper powder and 100 ml of nitrobenzene were charged, and the mixture was heated under reflux for 24 hours under Ar flow. After completion of the reaction, insoluble matter was removed by filtration, and the filtrate was evaporated. The obtained residue is n-hexane / toluene =
Silica gel column purification at 5/1, 12.0 g of 4 '
-[N, N'-di (3-biphenylylamino)]-4-
Iodo-1,1′-biphenyl was obtained (yield 40%).

In a 300 ml reaction vessel, 4 '-[N, N'-
Di (3-biphenylyl) amino] -4-iodo-1,
12.0 g (0.020 mol) of 1'-biphenyl, N,
3.03 g of N'-diphenylbenzidine (0.009mo
l), 5.52 g (0.04 mol) of potassium carbonate, 0.5 g of copper powder and 100 ml of nitrobenzene were charged, and the mixture was heated under reflux for 24 hours under an Ar stream. After completion of the reaction, insoluble matter was removed by filtration, and the filtrate was evaporated. The obtained residue was subjected to silica gel column purification twice with toluene / n-hexane = 2/1, and 6.90 g of N, N′-diphenyl-N,
N'-bis [-4 '-(N, N-di-3-biphenylylamino) biphenyl-4-yl] benzidine was obtained (yield 60%). This was recrystallized and purified with toluene and then 5.2.
A pale yellow transparent amorphous solid having a purity of 99.9% was obtained. This compound was also identified by mass spectrometry, IR, and NMR as in Example 4.

The other compounds represented by Chemical formulas 31 to 102 were also synthesized according to the above method, and mass spectrometry, IR, N
It was identified by MR.

Example 6 A glass substrate having a 200 nm thick ITO transparent electrode (anode) was ultrasonically cleaned using a neutral detergent, acetone and ethanol. The substrate is pulled out from boiling ethanol, dried, and washed with UV / O ₃ , and then fixed on a substrate holder of a vapor deposition device and 1 × 10 5.
^The pressure was reduced to ^-4 Pa or less.

Then, the compound of Example 1 was evaporated at a deposition rate of 0.
It was vapor-deposited at a thickness of 55 nm at 2 nm / sec to obtain a transparent amorphous thin film. Even if it is left in a thermostat of 30 ° C-100% RH and 60 ° C-90% RH, which is more severe than in the atmosphere, for 10 months or longer, crystallization does not occur and a stable amorphous state is maintained. , Showed high thin film forming ability and storage stability. Further, when the ionization potential Ip of the film produced in the same manner was measured with a low energy electron spectrometer AC-1 (manufactured by Riken Keiki),
It was 5.35 eV.

<Example 7> The compounds of Examples 2 and 3 were also tested in the same manner as in Example 6, but as in Example 6, no crystallization occurred even if they were allowed to stand for 10 months or more. The Ip of the deposited film was 5.36 eV and 5.38 eV, respectively.

<Example 8> The compounds of Examples 4 and 5 were tested in the same manner as in Example 6. Example 6
Similarly to the above, crystallization did not occur even if left for 10 months or more. The Ip of the deposited film was 5.32 eV and 5.28 eV, respectively.

<Comparative Example 1> Instead of the compound of Example 1, the compound N, N'-diphenyl-N, N'-di (3
-Methylphenyl) -4,4'-diamino-1,1'-
Biphenyl (melting point: 171.2 ° C, glass transition temperature: 6
1.3 ° C.) or the compound 1,1′-bis (4-
A thin film was prepared in the same manner as in Example 6, except that di-p-tolylaminophenyl) cyclohexane (melting point: 187.8 ° C., glass transition temperature: 79.9 ° C.) was used.
It was left to stand in a constant temperature bath of 30 ° C-100% RH. Example 6-
Crystallization started on the 3rd day of the compound and on the 30th day of the compound, even though the compound was left in an environmental condition milder in temperature than that of 8.

When the compound and the compound were measured for Ip in the same manner as in Example 6, both were found to be 5.40 eV.

Example 9 A glass substrate having a 200 nm thick ITO transparent electrode (anode) was ultrasonically cleaned using a neutral detergent, acetone and ethanol. The substrate is pulled out from boiling ethanol, dried, and washed with UV / O ₃ , and then fixed on a substrate holder of a vapor deposition device and 1 × 10 5.
^The pressure was reduced to ^-4 Pa or less.

First, the compound of Example 1 was deposited at a deposition rate of 0.2.
It was vapor-deposited to a thickness of 75 nm at nm / sec to form a hole injecting and transporting layer.

Next, while maintaining the reduced pressure, tris (8-quinolinolato) aluminum was deposited at a deposition rate of 0.2 nm.
It was vapor-deposited to a thickness of 50 nm at a rate of / sec to form an electron injecting / transporting / light emitting layer.

[0293] Further, while maintaining the reduced pressure state, MgAg
(Weight ratio 10: 1) 200nm at deposition rate 0.2nm / sec
Was evaporated to a cathode to obtain an organic EL device.

A direct current voltage was applied to this EL device, and it was continuously driven at a constant current density of 10 mA / cm ² in a dry atmosphere. In the initial stage, emission of yellow-green (maximum emission wavelength λ max = 500 nm) of 6.5 V and 400 cd / m ² was confirmed. The luminance half-life is 600 hours, during which the drive voltage rises by 4.0.
Vp, and the vapor deposition film of tris (8-quinolinolato) aluminum used as the light emitting layer had an Ip of 5.64 eV, which was different from the compound of Example 1 used as the hole injecting and transporting layer.
It was 0.29 eV.

<Examples 10 and 11> In Example 9,
An EL device was similarly obtained using the compound of Example 2 or the compound of Example 3 instead of the compound of Example 1, and the characteristics were similarly examined.

<Comparative Examples 2 and 3> In Example 9, the compound of Comparative Example 1 was used instead of the compound of Example 1 to obtain an EL device in the same manner, and the characteristics were similarly examined.

The characteristics of Examples 9 to 11 and Comparative Examples 2 to 3 are summarized in Table 1.

[0298]

[Table 1]

<Examples 12 and 13> In Example 9,
An EL device was obtained in the same manner by using the compound of Example 4 or 5 instead of the compound of Example 1, and the characteristics were examined in the same manner. In all cases, good results equivalent to or higher than those of Example 9 were shown. It was The difference in Ip from tris (8-quinolinolato) aluminum was 0.3 in the compound of Example 4.
2 eV, 0.36 eV for the compound of Example 5.

Example 14 A glass substrate having a 200 nm thick ITO transparent electrode (anode) was ultrasonically cleaned using a neutral detergent, acetone and ethanol. The substrate is pulled out from boiling ethanol, dried, and washed with UV / O ₃ , and then fixed on a substrate holder of a vapor deposition device and 1 × 10 5.
^The pressure was reduced to ^-4 Pa or less.

First, poly (thiophene-2,5-diyl) was vapor deposited at a vapor deposition rate of 0.1 nm / sec to a thickness of 20 nm.
The first hole injecting and transporting layer was used.

[0302] Next, with the reduced pressure being maintained, Example 1
Was vapor-deposited at a deposition rate of 0.2 nm / sec to a thickness of 55 nm to form a second hole injecting and transporting layer.

Further, while keeping the reduced pressure, tris (8-quinolinolato) aluminum was deposited at a deposition rate of 0.2 nm.
It was vapor-deposited to a thickness of 50 nm at a rate of / sec to form an electron injecting / transporting / light emitting layer.

[0304] Furthermore, while maintaining the reduced pressure, MgAg
(Weight ratio 10: 1) 200nm at deposition rate 0.2nm / sec
Was evaporated to a cathode to obtain an organic EL device.

A direct current voltage was applied to this EL device, and it was continuously driven at a constant current density of 10 mA / cm ² in a dry atmosphere. In the initial stage, light emission of yellow-green (maximum emission wavelength λ max = 500 nm) of 6.0 V and 350 cd / m ² was confirmed. The half-life time of luminance is 1600 hours, and the driving voltage rises during that period is 2.
It was 3V and there was no appearance or growth of dark spots.

Further, after that, current leakage did not occur and stable light emission was shown.

These results sufficiently satisfy the necessary conditions for application as a display, but have a higher current density (40 mA / cm ² ) in order to accelerate the life test.
It was driven continuously. At the initial stage, it showed a high brightness of 1400 cd / m ² , its half-life was 400 hours, and the driving voltage during that time was 5.0 V.

<Examples 15 and 16> In Example 14, an EL device was similarly obtained by using the compound of Example 2 or the compound of Example 3 instead of the compound of Example 1, and the current density was 10 mA / cm 2. ^The characteristics were similarly examined under the condition of ² .

For Examples 14 to 16 current density 10 mA
The characteristics under the condition of / cm ² are summarized in Table 2.

[0310]

[Table 2]

<Examples 17 and 18> EL devices were obtained in the same manner as in Example 14 except that the compound of Example 4 or the compound of Example 5 was used instead of the compound of Example 1, and the current density was 10 mA / cm 2. ^{When the} characteristics were similarly examined under the condition of ² ,
In all cases, good results equivalent to or higher than those of Example 14 were shown.

Example 19 A glass substrate having a 200 nm thick ITO transparent electrode (anode) was ultrasonically cleaned with a neutral detergent, acetone and ethanol. The substrate is pulled out from boiling ethanol, dried, and washed with UV / O ₃ , and then fixed on a substrate holder of a vapor deposition device and 1 × 10 5.
^The pressure was reduced to ^-4 Pa or less.

First, the compound of Example 1 and rubrene were vapor-deposited to a total thickness of 75 nm at vapor deposition rates of 0.2 nm / sec and 0.02 nm / sec, respectively, to form a hole injecting and transporting layer.

Then, while maintaining the reduced pressure, tris (8-quinolinolato) aluminum was deposited at a deposition rate of 0.2 nm.
It was vapor-deposited to a thickness of 50 nm at a rate of / sec to form an electron injecting / transporting / light emitting layer.

Further, with the reduced pressure maintained, MgAg
(Weight ratio 10: 1) 200nm at deposition rate 0.2nm / sec
Was evaporated to a cathode to obtain an organic EL device.

A direct current voltage was applied to this EL device, and it was continuously driven at a constant current density of 10 mA / cm ² in a dry atmosphere. In the early stage, a yellow emission (maximum emission wavelength λmax = 550 nm) of 6.2 V and 550 cd / m ² was confirmed. The half-life time of luminance is 1500 hours, and the driving voltage rises during that time is 2.8.
It was V.

<Examples 20 and 21> In Example 19, instead of the compound of Example 1, the compound of Example 2 or the compound of Example 3 was used to obtain EL devices in the same manner, and the characteristics were similarly examined. It was

Table 3 summarizes the characteristics of Examples 19 to 21.

[0319]

[Table 3]

<Examples 22 and 23> In Example 19, instead of the compound of Example 1, the compound of Example 4 or the compound of Example 5 was used to obtain EL devices in the same manner, and the characteristics were similarly examined. As a result, a good result equal to or higher than that of Example 19 was shown.

Example 24 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was ultrasonically cleaned with a neutral detergent, acetone, and ethanol. The substrate was taken out from boiling ethanol, dried, washed with UV / O ₃ , and then fixed on a substrate holder of a vacuum vapor deposition apparatus, and the vacuum chamber was depressurized to 1 × 10 ⁻⁴ Pa or less.

First, poly (thiophene-2,5-diyl) was deposited at a deposition rate of about 0.1 nm / sec. To a thickness of about 20 nm to form a first hole injecting and transporting layer.

Then, the vacuum chamber was returned to the atmosphere, and the vacuum chamber was depressurized again to 1 × 10 ⁻⁴ Pa or less. Then, the compound of Example 1 and rubrene were deposited at a deposition rate of 0.1 to 0.2 nm / sec, respectively.
It was co-deposited at a total thickness of about 55 nm at 0.01 to 0.02 nm / sec to form a second hole injecting and transporting layer.

Further, while maintaining the reduced pressure, tris (8-quinolinolato) aluminum was deposited at a deposition rate of 0.1 to
It was vapor-deposited at a thickness of about 50 nm at 0.2 nm / sec to form an electron injecting / transporting / light emitting layer.

Further, while maintaining the reduced pressure state, MgAg
(Weight ratio 10: 1) about 200 at a deposition rate of 0.2 nm / sec
An EL device was obtained by vapor deposition to a thickness of nm to form a cathode.

A direct current voltage was applied to this EL device, and it was continuously driven at a constant current density of 10 mA / cm ² in a dry atmosphere. In the early stage, a yellow emission (maximum emission wavelength λ max = 550 nm) of 6.2 V and 420 cd / m ² was confirmed. The half-life time of luminance is 2000 hours, during which the driving voltage rises 4.9.
It was V.

These results sufficiently satisfy the necessary conditions for application as a display, but in order to accelerate the life test, a higher current density (40 mA / cm ² ) was obtained.
It was driven continuously. At the initial stage, it showed a high luminance of 1490 cd / m ² , its half-life was 500 hours, and the driving voltage during that period was 3.5 V.

Example 25 An EL device was obtained in the same manner as in Example 24 except that the compound of Example 4 was used instead of the compound of Example 1 used for the second hole injecting and transporting layer. When the characteristics of this EL device were examined in the same manner as in Example 24, good results equivalent to or higher than those in Example 24 were shown.

Example 26 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was ultrasonically cleaned with a neutral detergent, acetone, and ethanol, and the substrate was taken out from boiling ethanol and dried. After cleaning with UV / O _3, the substrate was fixed to a substrate holder of a vacuum vapor deposition apparatus and the vacuum chamber was depressurized to 1 × 10 ⁻⁴ Pa or less.

First, the compound of Example 1 was deposited at a deposition rate of 0.1.
A hole injecting and transporting layer was obtained by vapor deposition at a thickness of about 0.2 nm / sec to a thickness of about 55 nm / sec.

Further, while maintaining the reduced pressure, tris (8-quinolinolato) aluminum as the hole injecting and transporting material and the electron injecting and transporting material are deposited at almost the same deposition rate (0.1
Co-evaporated at a rate of about 0.2 nm / sec) to form the mixed layer as a light emitting layer with a thickness of about 40 nm.

Further, the electron injecting and transporting material is deposited at a deposition rate of 0.1 to 0.2 nm / sec for about 30 while maintaining the reduced pressure.
It was vapor-deposited to a thickness of nm to form an electron injecting and transporting layer.

Further, while maintaining the reduced pressure state, MgAg
(Weight ratio 10: 1) about 200 at a deposition rate of 0.2 nm / sec
An EL device was obtained by vapor deposition to a thickness of nm to form a cathode.

A direct current voltage was applied to this EL device, and it was continuously driven at a constant current density of 10 mA / cm ² in a dry atmosphere. In the initial stage, 6.7 V, 470 cd / m ² yellow-green light emission (maximum emission wavelength λ max = 500 nm) was confirmed. The half-life time of luminance is 2000 hours, and the driving voltage rises during that period is 3.
It was 0V.

<Example 27> An EL device was prepared in the same manner as in Example 26 except that the compound of Example 4 was used instead of the compound of Example 1 used for the hole injecting / transporting layer and the mixed layer (light emitting layer). Got Example 2 of this EL device
When the characteristics were examined in the same manner as in Example 6, good results equal to or higher than those in Example 26 were shown.

Example 28 A glass substrate having a 200 nm thick ITO transparent electrode (anode) was ultrasonically cleaned using a neutral detergent, acetone and ethanol. The substrate was taken out from boiling ethanol, dried, washed with UV / O ₃ , and then fixed on a substrate holder of a vacuum vapor deposition apparatus, and the vacuum chamber was depressurized to 1 × 10 ⁻⁴ Pa or less.

First, poly (thiophene-2,5-diyl) was deposited at a deposition rate of about 0.1 nm / sec to a thickness of 20 nm to form a first hole injecting and transporting layer.

Then, the vacuum chamber was returned to the atmosphere, the pressure inside the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa or less, and the compound of Example 1 was deposited at a deposition rate of 0.1 to 0.2 nm / sec to a thickness of about 35 nm. Then, a second hole injecting and transporting layer was formed by vapor deposition.

Furthermore, with the reduced pressure maintained, tris (8) is used as the second hole injecting and transporting material and the electron injecting and transporting material.
-Quinolinolato) aluminum was co-deposited at almost the same deposition rate (0.1 to 0.2 nm / sec) to form the mixed layer as a light emitting layer to a thickness of about 40 nm.

Further, the electron injecting and transporting material is deposited at a deposition rate of 0.1 to 0.2 nm / sec for about 30 while maintaining the reduced pressure.
It was vapor-deposited to a thickness of nm to form an electron injecting and transporting layer.

Further, while maintaining the reduced pressure state, MgAg
(Weight ratio 10: 1) about 200 at a deposition rate of 0.2 nm / sec
An EL device was obtained by vapor deposition to a thickness of nm to form a cathode.

A direct current voltage was applied to this EL device, and it was continuously driven at a constant current density of 10 mA / cm ² in a dry atmosphere. In the initial stage, emission of yellow-green (maximum emission wavelength λ max = 500 nm) of 6.1 V and 350 cd / m ² was confirmed. The half-life of luminance is 3000 hours, and the driving voltage rises during that time is 5.
It was 0V.

Example 29 An EL device was obtained in the same manner as in Example 28 except that the thickness of the mixed layer was 10 nm, and the characteristics were evaluated in the same manner. As a result, the initial voltage was 6.2V, 3
60 cd / m ² yellow-green (maximum emission wavelength λmax = 500 nm)
Was confirmed to be emitted. The half-life time of luminance was 2,100 hours, and the driving voltage during that time was 3.3V.

<Example 30> The same operation as in Example 28 was carried out except that the compound of Example 4 was used instead of the compound of Example 1 used for the second hole injecting and transporting layer and the mixed layer (light emitting layer). An EL device was obtained. When the characteristics of this EL device were examined in the same manner as in Example 28, good results equivalent to or higher than those in Example 28 were shown.

In addition to the compounds of the present invention described above in Examples 9 to 30, one of the exemplified compounds of the present invention was used.
Various EL devices were similarly obtained by using the same kinds or more, and the characteristics were evaluated in the same manner. As a result, similar results were shown depending on the constitution of the device.

[0346]

The compound of the present invention has a high melting point and glass transition temperature, and a thin film formed by vapor deposition or the like is transparent and forms a stable amorphous state even at room temperature or higher, showing a smooth and good film quality. . Therefore, a thin film can be formed by itself without using a binder resin.

In the organic EL device of the present invention, since the compound for organic EL device containing the above compound is used in the organic compound layer, particularly preferably in the hole injecting and transporting layer, uniform and even surface emission is possible, High brightness can be stably obtained for a long time, and it has excellent durability and reliability.

In particular, in the organic EL device of the present invention in which the compound of the present invention is used in one layer and the polythiophene is used in the other one layer with two hole injecting and transporting layers, the driving voltage and its rise are suppressed to a low level. Therefore, a dark spot is not generated for a long time, and stable light emission can be maintained.

Furthermore, since the organic EL element of the present invention has an element structure in which the difference in Ip is optimized, the initial luminance reduction is suppressed and the light emission life is extended.

[0350] Further, in the case where rubrene is doped, the initial luminance is increased and the light emission life is extended.

Further, even when a mixed layer of the compound of the present invention and a compound having an electron injecting and transporting function is used as a light emitting layer, the light emission life is extended.

[Brief description of drawings]

FIG. 1 is a side view showing a configuration example of an organic EL element of the present invention.

FIG. 2 is a block diagram showing a configuration of a low energy electron spectrometer.

FIG. 3 is a graph showing the relationship between excitation energy and electron yield.

FIG. 4 is a diagram showing an infrared absorption spectrum of the compound of the present invention in Example 1.

5 is a diagram showing an NMR spectrum of the compound of the present invention in Example 1. FIG.

FIG. 6 is a diagram showing an infrared absorption spectrum of the compound of the present invention in Example 2.

FIG. 7 is a diagram showing an NMR spectrum of the compound of the present invention in Example 2.

FIG. 8 is a diagram showing an infrared absorption spectrum of the compound of the present invention in Example 3.

FIG. 9 is a diagram showing an NMR spectrum of the compound of the present invention in Example 3.

FIG. 10 is a diagram showing an infrared absorption spectrum of the compound of the present invention in Example 4.

11 is a diagram showing an NMR spectrum of the compound of the present invention in Example 4. FIG.

[Explanation of symbols]

 1 EL Element 2 Substrate 3 Anode 4 Hole Injecting and Transporting Layer 5 Light Emitting Layer 6 Electron Injecting and Transporting Layer 7 Cathode 10 Low Energy Electron Spectrometer 11 Ultraviolet Lamp 12 Monochromator 13 Detector 14 Low Energy Electron Counting Device 15 Control Device 16 Calculation Display Device 17 XY stage

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C09K 11/06 Z 9280-4H H01L 51/00 H05B 33/14

Claims (41)

[Claims] 1. A compound for an organic EL device, which is a tetraaryldiamine derivative represented by the following chemical formula 1. Embedded image [In Chemical Formula 1, R ₁ , R ₂ , R ₃ and R ₄ each represent an aryl group, an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, and R ₁ ,
At least one of R ₂ , R ₃ and R ₄ is an aryl group. r1, r2, r3 and r4 are each 0 or an integer of 1 to 5, the sum of r1, r2, r3 and r4 is an integer of 1 or more, and at least one aryl group is represented by R _{1 to} R _4. Exists. R ₅ and R ₆
Each represents an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or 1 respectively
Is an integer of ~ 4. ] 2. 2 to ₄ of R _{1 to} R ₄ are aryl groups, and at least 2 of these aryl groups are bound to the para position or meta position with respect to the bonding position of N. The compound for organic EL device according to claim 1. 3. The compound for an organic EL device according to claim 2, wherein at least one aryl group of R _{1 to} R ₄ is a phenyl group. 4. The compound for organic EL device according to claim 1, which is represented by the following chemical formula 2. Embedded image [In Chemical Formula 2, A ₁ , A ₂ , A ₃ and A ₄ are phenyl groups bonded to the para position or meta position with respect to the bonding position of N, and these may be the same or different. . R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r7, r8, r9 and r10 are each 0 or an integer of 1 to 4. R
₅ and R ₆ are each an alkyl group, an alkoxy group,
It represents an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 5. The compound for an organic EL device according to claim 2, wherein at least one aryl group of R _{1 to} R ₄ is a naphthyl group, anthryl group, pyrenyl group, perylenyl group or coronenyl group. 6. The compound for organic EL device according to claim 1, 2 or 5 represented by the following chemical formula 3. [Chemical 3] [In Chemical Formula 3, Ar represents an aryl group bonded to the para position or the meta position with respect to the bonding position of N. Z ₁ , Z ₂ and Z ₃ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. However, Z _1, at least one of the Z ₂ and Z ₃ represents an aryl group attached to the para-position or meta position with respect to the binding position of the _{N, Ar, Z 1, Z} 2 and Z ₃
Does not simultaneously form a phenyl group that is bonded to the para position or meta position with respect to the N bonding position. s1, s2 and s3 are each 0 or an integer of 1 to 5, s1,
The sum of s2 and s3 is an integer of 1 or more. R ₀ represents an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom. r0 is 0 or an integer of 1 to 4, respectively. R ₅ and R ₆ are
Each represents an alkyl group, an alkoxy group, an aryl group or a halogen atom, which may be the same or different. r5 and r6 are each 0 or 1
It is an integer of 4. ] 7. The compound for an organic EL device according to claim 1, which is represented by the following chemical formula 4. [Chemical 4] [In Chemical Formula 4, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. Good. r7, r8, r
9 and r10 are 0 or an integer of 1-4, respectively. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Each of r11, r12, r13 and r14 is 0 or an integer of 1 to 5. R
₅ and R ₆ are each an alkyl group, an alkoxy group,
It represents an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 8. The r5, r6, r7, r8, r9, r
The compound for organic EL device according to claim 7, wherein 10, r11, r12, r13 and r14 are each 0. 9. The compound for an organic EL device according to claim 1, which is represented by the following chemical formula 5. Embedded image [In Chemical Formula 5, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. Good. r7, r8, r
9 and r10 are 0 or an integer of 1-4, respectively. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Each of r11, r12, r13 and r14 is 0 or an integer of 1 to 5. R ₅
And R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 10. The r5, r6, r7, r8, r9,
The compound for organic EL device according to claim 9, wherein r10, r11, r12, r13 and r14 are each 0. 11. The compound for organic EL device according to claim 1, which is represented by the following chemical formula 6. [Chemical 6] [In Chemical Formula 6, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Good. r7, r8, r
9 and r10 are 0 or an integer of 1-4, respectively. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Each of r11, r12, r13 and r14 is 0 or an integer of 1 to 5. R ₅
And R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 12. The r5, r6, r7, r8, r9,
The compound for organic EL device according to claim 11, wherein r10, r11, r12, r13 and r14 are each 0. 13. The compound for organic EL device according to claim 1, which is represented by the following chemical formula 7. [Chemical 7] [In Chemical Formula 7, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Good. r7, r8, r
9 and r10 are 0 or an integer of 1-4, respectively. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Each of r11, r12, r13 and r14 is 0 or an integer of 1 to 5. R ₅
And R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 14. The r5, r6, r7, r8, r9,
14. The compound for organic EL device according to claim 13, wherein r10, r11, r12, r13 and r14 are each 0. 15. The compound for organic EL device according to claim 1, which is represented by the following chemical formula 8. Embedded image [In the chemical formula 8, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. Good. r7, r8, r
9 and r10 are 0 or an integer of 1-4, respectively. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Each of r11, r12, r13 and r14 is 0 or an integer of 1 to 5. R ₅
And R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 16. The r5, r6, r7, r8, r9,
16. The compound for organic EL device according to claim 15, wherein r10, r11, r12, r13 and r14 are each 0. 17. The compound for organic EL device according to claim 1, which is represented by the following chemical formula 9. [Chemical 9] [In Chemical Formula 9, R ₇ , R ₈ , R ₉ and R ₁₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Good. r7, r8, r
9 and r10 are 0 or an integer of 1-4, respectively. R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. Each of r11, r12, r13 and r14 is 0 or an integer of 1 to 5. R ₅
And R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 18. The r5, r6, r7, r8, r9,
18. The compound for organic EL device according to claim 17, wherein r10, r11, r12, r13 and r14 are each 0. 19. The method according to claim 1, wherein
The compound for organic EL devices of 5 or 6. [Chemical 10] [In Chemical Formula 10, Ar ₁ and Ar ₂ each represent an aryl group, and these may be the same or different. R ₁₅ and R ₁₆ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r15 and r16 are 0 or an integer of 1 to 4, respectively. R ₁₇ and R ₁₈ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r17 and r18 are 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 20. The r5, r6, r15, r16, r
The compound for an organic EL device according to claim 19, wherein 17 and r18 are each 0. 21. A method according to claim 1, 2 or 3,
The compound for organic EL devices of 5 or 6. [Chemical 11] [In Chemical Formula 11, Ar ₁ and Ar ₃ each represent an aryl group, and these may be the same or different. R ₁₅ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r15 and r20 are 0 or an integer of 1 to 4, respectively. R ₁₅ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r18 and r19 are 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 22. The r5, r6, r15, r18, r
22. The compound for an organic EL device according to claim 21, wherein 19 and r20 are each 0. 23. A method according to claim 1, wherein
The compound for organic EL devices of 5 or 6. [Chemical 12] [In Chemical Formula 12, Ar ₁ , Ar ₂ and Ar ₃ each represent an aryl group, and these may be the same or different. R ₁₅ , R ₁₆ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r15, r16 and r20 are each 0 or an integer of 1 to 4. R ₁₈
Represents an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom. r18 is 0 or an integer of 1 to 5. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r
5 and r6 are 0 or an integer of 1 to 4, respectively. ] 24. The r5, r6, r15, r16, r
The compound for an organic EL device according to claim 23, wherein 18 and r20 are each 0. 25. The method according to claim 1, represented by the following chemical formula 13,
The compound for organic EL devices of 5 or 6. [Chemical 13] [In Chemical Formula 13, Ar ₄ and Ar ₅ each represent an aryl group, and these may be the same or different. R ₁₅ and R ₁₆ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r15 and r16 are 0 or an integer of 1 to 4, respectively. R ₁₇ and R ₁₈ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r17 and r18 are 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 26. The r5, r6, r15, r16, r
The compound for an organic EL device according to claim 25, wherein 17 and r18 are each 0. 27. A method according to claim 1, wherein
The compound for organic EL devices of 5 or 6. Embedded image [In Chemical Formula 14, Ar ₄ and Ar ₆ each represent an aryl group, and these may be the same or different. R ₁₅ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, and these may be the same or different. r15 and r20 are 0 or an integer of 1 to 4, respectively. R ₁₈ and R ₁₉ each represent an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r18 and r19 are 0 or an integer of 1 to 5, respectively. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r5 and r6 are 0 or an integer of 1 to 4, respectively. ] 28. The r5, r6, r15, r18, r
The compound for an organic EL device according to claim 27, wherein 19 and r20 are each 0. 29. The method according to claim 1, 2 or 3,
The compound for organic EL devices of 5 or 6. [Chemical 15] [In Chemical Formula 15, Ar ₄ , Ar ₅ and Ar ₆ each represent an aryl group, and these may be the same or different. R ₁₅ , R ₁₆ and R ₂₀ each represent an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group or a halogen atom, which may be the same or different. r15, r16 and r20 are each 0 or an integer of 1 to 4. R ₁₈
Represents an alkyl group, an alkoxy group, an aryloxy group, an amino group or a halogen atom. r18 is 0 or an integer of 1 to 5. R ₅ and R ₆ each represent an alkyl group, an alkoxy group, an amino group or a halogen atom, which may be the same or different. r
5 and r6 are 0 or an integer of 1 to 4, respectively. ] 30. The r5, r6, r15, r16, r
30. The compound for an organic EL device according to claim 29, wherein 18 and r20 are each 0. 31. The organic EL according to claim 1.
An organic EL device having at least one layer containing at least one kind of device compound. 32. The organic EL device according to claim 31, further comprising at least one layer containing at least one compound of the organic EL device compound and a mixture of at least one compound having an electron injecting and transporting function. 33. The compound having an electron transporting function,
33. The organic EL device according to claim 32, which is tris (8-quinolinolato) aluminum. 34. The organic EL device according to claim 32, wherein the layer containing the mixture is a light emitting layer. 35. The organic EL device according to claim 31, wherein at least one layer containing at least one kind of the compound for organic EL device is doped with a fluorescent substance. 36. The organic EL device according to claim 35, wherein the fluorescent substance is rubrene. 37. The hole injecting and transporting layer is a layer containing at least one kind of the compound for organic EL device, and the hole injecting and transporting layer and the light emitting layer are included. Organic EL device. 38. The hole injecting and transporting layer is different in composition from 2
38. The organic EL device according to claim 37, which is composed of more than one layer. 39. The organic EL device according to claim 38, wherein at least one layer of the hole injecting and transporting layer contains polythiophene. 40. The method according to claim 37, further comprising an electron injecting and transporting layer.
39. The organic EL device according to any one of 39. 41. A layer containing at least one kind of the compound for organic EL device is a layer having a hole injecting and transporting function, and a layer having a light emitting function or a layer having an electron injecting and transporting function in contact with this layer. And the difference in ionization potential Ip between the layer having the hole injecting and transporting function and the layer having the light emitting function or the layer having the electron injecting and transporting function is 0.25 eV or more. 36 organic EL devices.