JP2003040844A - Organic electroluminescence element, organic electroluminescence element material and compound used for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescence element emitting light in high brightness, and to provide a compound used for the same. SOLUTION: This compound is represented by general formula (1) or (2) [one of T1 to T2 is a substituent; R1 to R14 are each H or a substituent; Ar1 and Ar2 are each an aromatic group; one of Ar1 and Ar2 is 1-naphthyl, 2- naphthyl, 1-anthryl; one of T5 to T8 is a substituent; R15 to R18 are each H or a substituent; Ar3 to Ar6 are each an aromatic group; one of Ar3 to Ar6 is 1-naphthyl, 2-naphthyl or 1-anthryl]. The organic electroluminescence element contains the compounds in a light-emitting layer or a hole transport layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescence (hereinafter abbreviated as organic EL) element and an organic electroluminescence element material, and specifically, a light emitting type multicolor or full color display, a display panel, and the like. The present invention relates to an organic electroluminescence element and an organic electroluminescence element material that are preferably used in consumer and industrial display devices.

[0002]

2. Description of the Related Art An electroluminescent display (ELD) is used as a light emitting type electronic display device.
There is. Examples of the ELD constituent elements include an inorganic electroluminescent element and an organic electroluminescent element. The inorganic electroluminescent device is
Although it has been used as a flat light source, a high alternating voltage is required to drive a light emitting element. An organic electroluminescence device has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode, and electrons and holes are injected into the light emitting layer to recombine to generate excitons (excitons). It is an element that emits light by utilizing the emission of light (fluorescence / phosphorescence) when the excitons are deactivated, and can emit light at a voltage of several V to several tens of V. Further, it is a self-luminous type. Therefore, it is highly dependent on the viewing angle and has high visibility, and since it is a thin-film type complete solid-state element, it is attracting attention from the viewpoints of space saving, portability, and the like.

However, as an organic EL element for practical use in the future, it is desired to develop an organic EL element which emits light efficiently, with high brightness and long life with further low power consumption.

Various organic EL devices have been reported so far, but at present, they have been put into practical use only in monocolor or area color.

One of conventional full-color methods for organic EL elements is a method of directly patterning each pixel of blue (B), green (G) and red (R). Since it is necessary to separately paint in different colors, the yield at the time of manufacture is poor, and the fact that no red light emitting material with high color purity has been found has been an obstacle to practical use.

Further, in the method of combining white light emission and a color filter described in JP-A-7-220871, etc.,
There are drawbacks such as low utilization efficiency of light and a white light emitting element having a short life and a low luminous efficiency.

Further, by using a blue light emitting material described in JP-A-3-152897, etc., the blue light is absorbed to absorb B, G,
In the method of applying the color conversion layer that emits light to R, it is not necessary to separately paint the light emitting element into three colors, and the yield during manufacturing is improved. Furthermore, in principle, the light utilization efficiency is high. However, when a material that emits EL light in blue is used and a red color is produced by color conversion, the color purity is poor. This is because a plurality of organic compounds having a small Stokes shift are used as a compound for color conversion, and thus it is necessary to perform color conversion a plurality of times when color conversion from blue to red.

The full color system of the organic EL device of the present invention uses a blue-violet to near-ultraviolet light emitting material and absorbs the blue-violet to near-ultraviolet light to emit light in B, G and R. It is envisioned that the method will be applied. Blue-violet like the present invention ~
In the case of near-ultraviolet light emission, there is a possibility that an inorganic compound having a large Stokes shift, such as an Eu ³⁺ complex or an inorganic phosphor containing Eu ³⁺ , can be used. The red color purity and luminous efficiency can be increased.

When this system is adopted, a material that emits blue-violet to near-ultraviolet light is required. Conventional materials that emit blue-blue-violet emission are sufficient in various properties such as emission brightness and emission life. There are still no reported cases that satisfy such performance. For example, in Japanese Patent Laid-Open No. 3-152897, p-
It has been reported that an organic electroluminescence device containing quarterphenyl emits light at 420 nm, but the emission brightness is low and not sufficient.

Further, when the polysilane compound disclosed in JP-A No. 11-26159 is used, ultraviolet to near-ultraviolet light emission can be obtained relatively easily, but the polysilane compound is generally unstable. It is difficult to maintain this light emission at room temperature, and one that emits light at room temperature has been recently discovered, but its light emission efficiency is low, and when it is used as an organic EL device, the light emission life is extremely short. Had.

Further, by simply using a material having fluorescence emission in blue-violet to near-ultraviolet as an organic EL element and laminating a conventionally known hole injection layer or hole-transporting layer, a desired blue-violet to near-violet layer can be obtained. It was found that it was not possible to obtain ultraviolet light emission.

4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] is added to the hole injection layer.
N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1′-biphenyl] -4,4 ′ is formed in a hole transport layer such as triphenylamine (m-MTDATA).
-Diamine (TPD), 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NP
When a hole injection layer or a hole transport layer using a conventionally known material such as D) is used for an organic EL device, even if a material emitting light in a blue-violet to near-ultraviolet wavelength shorter than that is used for the light-emitting layer. It was found that light emission was obtained from the compounds of the hole injection layer and the hole transport layer, and only blue light emission was obtained.

[0013] TPD has hitherto been known as a material for a hole transport layer, but since it has fluorescence emission, it can be considered to be used as a light emitting material. However, its emission color was blue, and the emission wavelength was too long for our purpose and was not suitable.

Further, in JP-A-8-48656 and JP-A-10-88119 in which compounds similar to TPD are described, a benzidine derivative in which four or two aryl groups of tetraarylbenzidine are replaced by biphenyl groups, respectively. However, it is disclosed that the organic EL device has excellent durability and is preferable. However, when these are used as the light emitting material, the emission color becomes longer than that of TPD,
The emission color from blue to blue-green was not suitable for our purpose because the emission wavelength was too long.

Further, in Japanese Patent Laid-Open No. 11-312586, N
It has been disclosed that a benzidine derivative in which two naphthyl groups of PD are replaced with phenanthryl groups is excellent in durability as an organic EL device and is preferable, but these luminescent colors emit blue light having a maximum emission wavelength at 455 nm. It was not suitable for our purpose because the emission wavelength was too long.

[0016]

As described above, as an organic electroluminescence device, an organic E having a long life and a high brightness, which emits light having a short emission wavelength of blue-violet to near-ultraviolet.
L element is required.

Therefore, an object of the present invention is to provide a novel compound which emits light with high brightness and long life in blue-violet to near-ultraviolet, an organic electroluminescence device which emits light with high brightness, an organic electroluminescence device with long life, and easy manufacture. It provides at least one organic electroluminescent device.

[0018]

The above objects of the present invention can be achieved by the following constitutions.

1) The compound represented by the general formula (1)
1 " In the above general formula (1), 2) T₁~ T_FourAre all replaced
Being a group, 3) R ₁~ R₁₄Are hydrogen atom and halo, respectively
Gen atom, alkyl group, cycloalkyl group, aryl
Group, alkoxy group, aryloxy group, dialkylamido
It is preferably a no group or a diarylamino group.

4) The compound represented by the general formula (2)
2 " In the above general formula (2), 5) T_Five~ T₈Are all replaced
Being a group, 6) R ₁₅~ R₁₈Are hydrogen atom and halo, respectively
Gen atom, alkyl group, cycloalkyl group, aryl
Group, alkoxy group, aryloxy group, dialkylamido
It is preferably a no group or a diarylamino group.

7) An organic electroluminescence device material containing the compound according to any one of 1) to 6).

8) An organic electroluminescence device containing the device material described in 7). 9) An organic electroluminescence device containing the compound according to any one of 1) to 6) in a light emitting layer.

10) An organic electroluminescent device containing the compound according to any one of 1) to 6) in a hole transport layer.

11) Purish of CIE chromaticity coordinates
Blue (purple blue), Blueish Purple
The organic electroluminescence device according to 8), 9) or 10), which emits light in a (blue-violet) or purple (purple) region.

12) 400 to 500 nm, respectively, by absorbing electroluminescence emission of the above compound, 5
Any one of 8) to 11) having at least one conversion layer containing at least one inorganic compound having a maximum emission wavelength within the range of 01 to 600 nm and 601 to 700 nm.
The organic electroluminescence device according to the item.

The present invention will be described in more detail below. Figure 1
The structure of the organic EL element will be described with reference to. The organic EL element is composed of a light emitting layer 3 and an electrode composed of a cathode 1 and an anode 5. The light emitting layer 3 has a structure in which it is sandwiched between the anode 5 and the cathode 1 via the hole transport layer 4 and the electron transport layer 2, respectively. When an electric current is applied to the electrodes, the organic compound contained in the light emitting layer 3 emits light. This is the cathode 1
Positive and negative carriers are injected from the anode 5 and the carriers move and recombine in the organic layer to form a singlet excited state of the compound, and the singlet excited state is deactivated from the singlet excited state to the ground state. Are believed to emit light.

As shown in FIG. 1, the organic EL element is provided with color conversion layers 7B, 7G and 7R, and these color conversion layers 7B and 7R are provided.
By G and 7R, the light of the compound contained in the light emitting layer can be converted into light having different wavelengths. By providing three kinds of organic EL elements having such color conversion layers having different conversion wavelengths, full color can be realized.

In the full-color system of the organic EL device of the present invention, a blue-violet to near-ultraviolet light emitting material is used, and a color conversion layer that absorbs the blue-violet to near-ultraviolet light and emits B, G, and R is coated. It is supposed to be installed. In the case of blue-violet to near-ultraviolet light emission as in the present invention, there is a possibility that an inorganic compound having a large Stokes shift such as an Eu ³⁺ complex or an inorganic phosphor containing Eu ³⁺ can be used. A red color can be produced by converting the number of times, and the color purity of red and luminous efficiency can be improved.

The inventors paid attention to TPD as a material that emits fluorescence in the blue-violet to near-ultraviolet light, and earnestly studied the shortening of the wavelength by twisting the biphenyl moiety of tetraphenylbenzidine. As a result, by using the compound of the present invention, it was possible to produce an organic electroluminescence device which emits light of high brightness and long life in blue-violet to near-ultraviolet.

When the fluorescent emission of the material of the light emitting layer is blue-violet to near-ultraviolet light, the material having fluorescent emission in the blue-violet to near-ultraviolet light of the present invention can be used as a hole transport material in an organic EL device. It is possible to obtain blue-violet to near-ultraviolet light emission as it is.

The light emitting layer in the present invention is, in a broad sense,
A layer that emits light when a current is applied to an electrode composed of a cathode and an anode. Specifically, it refers to a layer containing an organic compound that emits light when a current is applied to an electrode composed of a cathode and an anode.

Usually, the light emitting layer has a structure in which the light emitting layer is sandwiched between a pair of electrodes. The organic EL device of the present invention has a hole injection layer, an electron injection layer, a hole transport layer and an electron transport layer in addition to the light emitting layer as required, and has a structure sandwiched between a cathode and an anode.

Specifically, there are the following structures. (I) Anode / light emitting layer / cathode (ii) Anode / hole injection layer / light emitting layer / cathode (iii) Anode / light emitting layer / electron injection layer / cathode (iv) Anode / hole injection layer / light emitting layer / electron Injection layer / cathode (v) Anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode Furthermore, a cathode buffer layer (lithium fluoride) is provided between the electron injection layer and the cathode. Etc.) may be inserted. Further, an anode buffer layer (copper phthalocyanine or the like) may be inserted between the anode and the hole injection layer.

The above-mentioned light emitting layer includes a hole injection layer on the light emitting layer itself,
You may provide an electron injection layer, a hole transport layer, an electron transport layer, etc. That is, (1) an injection function capable of injecting holes from the anode or the hole injection layer and applying electrons from the cathode or the electron injection layer when an electric field is applied to the light emitting layer,
(2) A transport function of moving the injected charges (electrons and holes) by the force of the electric field, (3) a light emitting function of providing a field for recombination of electrons and holes inside the light emitting layer, and connecting this to light emission, In this case, at least one of a hole injection layer, an electron injection layer, a hole transport layer, and an electron transport layer must be provided separately from the light emitting layer. Will disappear. Further, the hole injection layer, the electron injection layer, the hole transport layer, the electron transport layer, and the like may contain a compound that emits light to impart a function as a light emitting layer.

The light-emitting layer may have different easiness of injecting holes and easiness of injecting electrons, and has a large or small transport function represented by mobility of holes and electrons. Good, but
Those having a function of moving at least one of the charges are preferable.

As a method for forming a light emitting layer using the above materials, for example, a vapor deposition method, a spin coating method, a casting method,
It can be formed by thinning it by a known method such as the LB method, but a molecular deposition film is particularly preferable. Here, the molecular deposition film is a thin film formed by depositing the above compound in a vapor phase state, or a film formed by solidifying a molten state or a liquid phase state of the compound. Usually, this molecular deposited film can be distinguished from a thin film (molecular cumulative film) formed by the LB method based on the difference in agglomeration structure and higher-order structure and the functional difference resulting therefrom.

Further, this light emitting layer is disclosed in JP-A-57-5178.
As described in No. 1, it can be formed by dissolving the above light emitting material together with a binder such as a resin in a solvent to form a solution, and then thinning the solution by a spin coating method or the like.
The thickness of the light emitting layer thus formed is not particularly limited and can be appropriately selected depending on the situation, but is usually in the range of 5 nm to 5 μm.

Next, the compound represented by formula (1) or (2) of the present invention will be described in detail. In the general formula (1), Ar ₁ and Ar ₂ are aromatic groups which may have a substituent, and at least one is 1-naphthyl, 2-naphthyl, 1-anthryl, 9-anthryl, 1-. Pyrenyl,
2-pyrenyl or an aromatic heterocyclic group.

R _{1 to} R ₁₄ each represent a hydrogen atom or a substituent, and the substituent is a halogen atom, an alkyl group (methyl, ethyl, i-propyl, hydroxyethyl,
Methoxymethyl, trifluoromethyl, perfluoropropyl, perfluorobutyl, perfluoro-t-butyl, t-butyl etc.), cycloalkyl group (cyclopentyl, cyclohexyl etc.), aralkyl group (benzyl, 2
-Phenethyl, etc.), aryl groups (phenyl, naphthyl,
p-tolyl, p-chlorophenyl, etc.), alkoxy group (methoxy, ethoxy, i-propoxy, butoxy, etc.), aryloxy group (phenoxy, etc.), alkenyl group, carboxyl group, hydroxyl group, amide group, alkoxycarbonyl group, etc. Can be mentioned. Further, these groups may be further substituted with the above-mentioned substituents, or may be condensed with each other to form a ring. However, at least one of R _{1 to} R ₄ is a substituent.

In the general formula (2), Ar _{3 to} Ar ₆
Is an aromatic group which may have a substituent, and at least one is 1-naphthyl, 2-naphthyl, 1-anthryl, 9
-Anthryl, 1-pyrenyl, 2-pyrenyl or an aromatic heterocyclic group.

R _{15 to} R ₁₈ each represent a hydrogen atom or a substituent, and as the substituent, a halogen atom, an alkyl group (methyl, ethyl, i-propyl, hydroxyethyl,
Methoxymethyl, trifluoromethyl, perfluoropropyl, perfluorobutyl, perfluoro-t-butyl, t-butyl etc.), cycloalkyl group (cyclopentyl, cyclohexyl etc.), aralkyl group (benzyl, 2
-Phenethyl, etc.), aryl groups (phenyl, naphthyl,
p-tolyl, p-chlorophenyl, etc.), alkoxy group (methoxy, ethoxy, i-propoxy, butoxy, etc.), aryloxy group (phenoxy, etc.), alkenyl group, carboxyl group, hydroxyl group, amide group, alkoxycarbonyl group, etc. Can be mentioned. Further, these groups may be further substituted with the above-mentioned substituents, or may be condensed with each other to form a ring. However, at least one of R _{15 to} R ₁₈ is a substituent.

In the general formula (1), R ₁ , R ₂ , R ₃ ,
As R ₄ , an alkyl group is preferable, and above all, it is particularly preferable that any two or all four of them are methyl groups. Similarly in the general formula (2), R _{15 to} R _{18 are also the same.}
It is particularly preferable that any two or all four of them are methyl groups. In this way, by introducing a substituent in the center of the biphenyl group, the molecule can have a more twisted structure, and the emission wavelength can be a shorter wavelength blue to blue-violet emission color.

The color emitted by the organic compound of the present invention is shown in Fig. 4.16 on page 108 of "Handbook of Color Science by New Edition" (edited by the Japanese Society for Color Science, Tokyo University Press, 1985).
The result measured by the spectral radiance meter CS-1000 (manufactured by Minolta Co., Ltd.) is determined by the color when it is fitted to the CIE chromaticity coordinates, and the measurement result is the purple-blue region of the CIE chromaticity coordinates "P.
“urplish Blue”, a blue-violet region “Bl
"uish Purple" or "P which is a purple region
Say to enter "urple".

Since the compounds represented by the general formulas (1) and (2) have a high glass transition temperature (Tg), they have sufficient thermal stability as a material for an organic electroluminescence device. Tg is preferably 100 degrees or more.

Since the compounds represented by the general formulas (1) and (2) are compounds that emit light with high brightness, they are of course useful as compounds that emit light in the light emitting layer of the organic electroluminescence device. In addition to the above, by utilizing the above properties, the compound can be used as a material such as a labeled compound for a drug using fluorescence emission.

The molecular weight of the compounds represented by formulas (1) and (2) is preferably in the range of 500 to 2000. When the molecular weight is within this range, the light emitting layer can be easily produced by the vacuum vapor deposition method, and the production of the organic EL device becomes easy. Furthermore, the thermal stability of the organic compound in the organic EL device is improved.

The compounds represented by the general formulas (1) and (2) are any of a hole injecting layer, an electron injecting layer, a hole transporting layer and an electron transporting layer in addition to the light emitting layer of the organic EL device. Can also be used for Preferably, a light emitting layer or a hole injection layer,
It is a hole transport layer.

Specific examples of the compound represented by formula (1) or (2) in the invention are shown below, but the invention is not limited thereto.

[0049]

[Chemical 3]

[0050]

[Chemical 4]

[0051]

[Chemical 5]

[0052]

[Chemical 6]

[0053]

[Chemical 7]

[0054]

[Chemical 8]

[0055]

[Chemical 9]

[0056]

[Chemical 10]

[0057]

[Chemical 11]

[0058]

[Chemical 12]

[0059]

[Chemical 13]

[0060]

[Chemical 14]

[0061]

[Chemical 15]

[0062]

[Chemical 16]

[0063]

[Chemical 17]

[0064]

[Chemical 18]

[0065]

[Chemical 19]

[0066]

[Chemical 20]

[0067]

[Chemical 21]

[0068]

[Chemical formula 22]

[0069]

[Chemical formula 23]

[0070]

[Chemical formula 24]

Next, the hole injection layer and the electron injection layer will be described. The hole injection layer has a function of transmitting holes injected from the anode to the light emitting layer. By interposing this hole injection layer between the anode and the light emitting layer, many holes can be generated at a lower electric field. Are injected into the light emitting layer, and the electrons injected into the light emitting layer from the cathode or the electron injection layer are accumulated at the interface in the light emitting layer due to the electron barrier existing at the interface between the light emitting layer and the hole injection layer. The device has excellent light emission performance such as improved light emission efficiency. The material of the hole injection layer (hereinafter referred to as the hole injection material) is not particularly limited as long as it has the above-mentioned preferable properties, and conventionally, as a charge injection / transport material for holes in an optical transmission material. It can be arbitrarily selected from the conventionally used ones and known ones used for the hole injection layer of EL elements.

The hole injecting material has any of hole injecting property and electron blocking property, and may be either organic substance or inorganic substance. Examples of the hole injection material include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives. , Fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers,
Examples thereof include conductive polymer oligomers, especially thiophene oligomers. As the hole injecting material, the above materials can be used, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

Typical examples of the aromatic tertiary amine compound and the styrylamine compound are N, N, N ', N'.
-Tetraphenyl-4,4'-diaminophenyl; N,
N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD); 2,2-bis (4-di-p-tolyl) Aminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′,
N'-tetra-p-tolyl-4,4'-diaminobiphenyl; 1,1-bis (4-di-p-tolylaminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl ) Phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N'-di (4-methoxyphenyl) -4,4'-diaminobiphenyl; N,
N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) biphenyl; N, N, N-tri (p-tolyl) amine; 4- (di- p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N,
N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4′-N, N-diphenylaminostilbenzene; N-phenylcarbazole, and further
Those having two fused aromatic rings in the molecule described in U.S. Pat. No. 5,061,569, such as 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD ), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] in which the triphenylamine units described in JP-A-4-308688 are linked in a three star burst type. Triphenylamine (MTDATA) etc. are mentioned.

Inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material. The hole injection layer can be formed by thinning the hole injection material by a known method such as a vacuum vapor deposition method, a spin coating method, a casting method, and an LB method. The thickness of the hole injection layer is not particularly limited, but is usually 5 nm to 5 nm.
It is about μm.

This hole injection layer is formed of one or two of the above materials.
It may have a one-layer structure composed of at least one kind or a laminated structure composed of a plurality of layers having the same composition or different compositions.

The electron injection layer has only to have a function of transmitting the electrons injected from the cathode to the light emitting layer, and its material can be arbitrarily selected from conventionally known compounds.

Materials used for this electron injection layer (hereinafter,
Examples of electron injection materials) include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, heterocyclic tetracarboxylic acid anhydrides such as naphthaleneperylene, carbodiimides, fluorenylidene methane derivatives, anthraquinone dimethane and Examples thereof include anthrone derivative and oxadiazole derivative. Further, a series of electron-transporting compounds described in JP-A-59-194393 are disclosed as materials for forming a light emitting layer in the publication, but as a result of investigations by the present inventors, they are used as electron injection materials. It turned out to be usable. Further, in the above oxadiazole derivative, a thiadiazole derivative in which an oxygen atom of the oxadiazole ring is substituted with a sulfur atom, or a quinoxaline derivative having a quinoxaline ring known as an electron-withdrawing group can also be used as an electron injecting material. or,
Metal complexes of 8-quinolinol derivatives, such as tris (8
-Quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum, tris (2-methyl-8-quinolinol)
Aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Z
nq), etc., and the central metals of these metal complexes are In, M
A metal complex replacing g, Cu, Ca, Sn, Ga or Pb can also be used as the electron injecting material. In addition, metal-free or metal phthalocyanine, or those whose terminal is substituted with an alkyl group, a sulfonic acid group, or the like can also be preferably used. Further, the distyrylpyrazine derivative exemplified as the material for the light emitting layer can also be used as the electron injecting material, and as with the hole injecting layer, n
Inorganic semiconductors such as type-Si and n-type-SiC can also be used as the electron injection material.

The electron injection layer can be formed by forming the above compound into a film by a known thinning method such as a vacuum vapor deposition method, a spin coating method, a casting method and an LB method.

The thickness of the electron injection layer is not particularly limited, but is usually selected in the range of 5 nm to 5 μm. The electron injection layer may have a single-layer structure composed of one kind or two or more kinds of these electron injection materials, or a laminated structure composed of a plurality of layers having the same composition or different compositions.

Next, as a preferable example of producing an organic EL device, the above-mentioned anode / hole injection layer / light-emitting layer / electron injection layer /
The EL element including the cathode will be described.

First, a thin film of a desired electrode material, for example, a material for an anode, is formed on a suitable substrate by a method such as vapor deposition or sputtering so as to have a thickness of 1 μm or less, preferably 10 nm to 200 nm. To make.
Next, on this, a hole injection layer, a light emitting layer, which are element materials,
A thin film made of the material of the electron injection layer is formed. Further, a buffer layer (electrode interface layer) is provided between the anode and the light emitting layer or hole injection layer, and between the cathode and the light emitting layer or electron injection layer.
May be present.

The buffer layer is a layer provided between the electrode and the organic layer in order to reduce the driving voltage and improve the luminous efficiency.
Second edition of January 30, published by NTS),
It is described in detail in Chapter 2 "Electrode Materials" (pages 123 to 166), and includes an anode buffer layer and a cathode buffer layer.

The anode buffer layer is formed as described in JP-A-9-4547.
The details are also described in No. 9, No. 9-260062, No. 8-288069 and the like, and as a specific example, a phthalocyanine buffer layer represented by copper phthalocyanine,
Examples thereof include an oxide buffer layer typified by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) and polythiophene.

The cathode buffer layer is described in JP-A-6-3258.
No. 71, No. 9-17574, No. 10-74586, etc. are also described in detail. Specifically, a metal buffer layer typified by strontium and aluminum, an alkali metal compound typified by lithium fluoride, etc. Examples thereof include a buffer layer, an alkaline earth metal compound buffer layer typified by magnesium fluoride, and an oxide buffer layer typified by aluminum oxide.

It is desirable that the buffer layer is an extremely thin film, and the film thickness is 0.1 to 10 depending on the material.
The range of 0 nm is preferred.

In addition to the above basic constituent layers, if necessary, layers having other functions may be laminated, for example, JP-A Nos. 11-204258 and 11-204359.
And "organic EL device and its industrial frontier (above)", page 237, etc., may have a functional layer such as a hole blocking (hole blocking) layer.

The buffer layer may function as a light emitting layer when at least one kind of the compound of the present invention is present in at least one of the cathode buffer layer and the anode buffer layer.

Next, the electrodes of the organic EL element will be described. The electrodes of the organic EL element are composed of a cathode and an anode. As the anode in this organic EL element, a material having an electrode substance of a metal, an alloy, an electrically conductive compound or a mixture thereof having a large work function (4 eV or more) is preferably used. Specific examples of such an electrode material include metals such as Au, CuI, indium tin oxide (ITO), and Sn.
Conductive transparent materials such as O ₂ and ZnO are mentioned.

For the above-mentioned anode, a thin film may be formed by a method such as vapor deposition or sputtering of these electrode substances, and a pattern of a desired shape may be formed by a photolithography method, or when pattern accuracy is not required so much. (About 100 μm or more), a pattern may be formed through a mask having a desired shape during vapor deposition or sputtering of the electrode material. When light emission is taken out from this anode, it is desirable that the transmittance be greater than 10%,
The sheet resistance of the anode is preferably several hundred Ω / □ or less. Further, the film thickness depends on the material, but is usually 10 nm to 1 μm.
m, preferably 10 to 200 nm.

On the other hand, as the cathode, a metal having a low work function (4 eV or less) (referred to as an electron injecting metal), an alloy, an electrically conductive compound, or a mixture thereof is used as an electrode material. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum /
Aluminum oxide (Al ₂ O ₃ ) mixture, indium, lithium / aluminum mixture, rare earth metal and the like can be mentioned. Among these, from the viewpoint of electron injecting property and durability against oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function value, for example, a magnesium / silver mixture, magnesium / magnesium / Aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide mixtures, lithium / aluminum mixtures and the like are suitable.

The above cathode can be produced by forming a thin film of these electrode substances by a method such as vapor deposition or sputtering. The sheet resistance of the cathode is several hundred Ω / □
The following is preferred, and the film thickness is usually selected in the range of 10 nm to 1 μm, preferably 50 to 200 nm. In order to transmit light, it is convenient that either the anode or the cathode of the organic EL element is transparent or semi-transparent and the light emission efficiency is improved.

Next, a method for manufacturing the organic EL element will be described. As a method for thinning the film, there are the spin coating method, the casting method, the vapor deposition method and the like as described above, but the vacuum vapor deposition method is preferable from the viewpoints that a uniform film is easily obtained and pinholes are hard to be generated. When a vacuum vapor deposition method is used for thinning, the vapor deposition conditions vary depending on the type of compound used, the target crystal structure of the molecular deposited film, the association structure, etc., but generally, the boat heating temperature is 50 to 450 ° C., and the degree of vacuum is 10
^-6 to 10 ^-3 Pa, vapor deposition rate of 0.01 to 50 nm / sec, substrate temperature of -50 to 300 ° C., and film thickness of 5 nm to 5 μm are preferably selected as appropriate.

After the formation of these layers, a thin film made of the material for the cathode is formed thereon and has a thickness of 1 μm or less, preferably 50 to 200 n.
A desired organic EL device can be obtained by forming a film having a thickness in the range of m by a method such as vapor deposition or sputtering and providing a cathode. In order to manufacture this organic EL device, it is preferable to consistently manufacture from the hole injecting layer to the cathode by vacuuming once, but the manufacturing order is reversed, and the cathode, the electron injecting layer, the light emitting layer, and the hole injecting It is also possible to fabricate the layers and the anode in this order.

When a DC voltage is applied to the organic EL device thus obtained, light emission can be observed by applying a voltage of about 5 to 40 V with the anode having a positive polarity and the cathode having a negative polarity. Also, even if voltage is applied with the opposite polarity, no current flows,
No light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the − state. The waveform of the alternating current applied may be arbitrary.

Next, the color conversion layer will be described. In a broad sense, the color conversion layer referred to in the present invention refers to a layer that converts light emitted from the light emitting layer of the organic EL element into light having different wavelengths. Specifically, it refers to a layer containing a substance that absorbs light emitted from a light emitting layer and emits light of different wavelengths.

An organic EL device according to claim 8 of the present invention is
As the color conversion layer, a color conversion layer containing an inorganic compound that is excited by the emission wavelength of the compound in the light emitting layer and emits light with a maximum emission wavelength in the range of 400 to 500 nm, the emission wavelength of the compound in the light emitting layer And a color conversion layer containing an inorganic compound that emits light having a maximum emission wavelength within the range of 501 to 600 nm, and is excited by the emission wavelength of the compound in the emission layer, 60
It is preferable to have at least one of the color conversion layers containing an inorganic compound that emits light with a maximum emission wavelength in the range of 1 to 700 nm.

By making all the color conversion materials contained in the color conversion layer inorganic compounds, full-color organic E
It is possible to provide an L element having a long life and low power consumption. Further, four or more color conversion layers may be provided as long as full color conversion is efficiently achieved.

The inorganic compound contained in the color conversion layer of the organic EL element is preferably an inorganic phosphor or a rare earth complex phosphor. The composition of the inorganic phosphor is not particularly limited, but Y ₂ O ₂ S, Zn ₂ SiO ₄ , Ca ₅ (PO ₄ ) ₃ Cl, which are the crystal matrix, are used.
Oxides such as ZnS, SrS, CaS
Such as Ce, Pr, Nd, Pm, S
m, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb
Ions of rare earth metals such as Ag, Al, Mn, In, C
A combination of metal ions such as u and Sb as an activator or co-activator is preferable.

More specifically, a metal oxide is preferable as the crystal matrix, and for example, (X) ₃ Al ₁₆ O ₂₇ ,
(X) ₄ Al ₁₄ O ₂₅ , (X) ₃ Al ₂ Si ₂ O ₁₀ , (X) ₄
Si ₂ O ₈ , (X) ₂ Si ₂ O ₆ , (X) ₂ P ₂ O ₇ , (X) _{2
P 2 O 5, (X)} 5 (PO 4) 3 Cl, (X) 2 Si 3 O 8 -2
(X) Cl ₂ [where X represents an alkaline earth metal.
The alkaline earth metal represented by X may be a single component or a mixed component of two or more kinds, and the mixing ratio thereof may be arbitrary. ] Alkaline earth metal-substituted aluminum oxide, silicon oxide, phosphoric acid, halophosphoric acid and the like are listed as typical examples.

Other preferable crystal matrixes include zinc oxides and sulfides, oxides of rare earth metals such as yttrium, gadolinium and lanthanum, and a part of oxygen in the oxides replaced with sulfur atoms (sulfides). Examples thereof include sulfides of rare earth metals and oxides or sulfides thereof mixed with an arbitrary metal element.

Preferred examples of the crystal matrix are listed below.
Mg_FourGeO_5.5F, Mg_FourGeO₆, ZnS, Y₂O₂S,
Y₃Al_FiveO₁₂, Y₂SiO_Ten, Zn₂SiO_Four, Y₂O₃,
BaMgAl_TenO₁₇, BaAl₁₂O₁₉, (Ba, Sr,
Mg) O ・ aAl₂O₃, (Y, Gd) BO₃, (Zn,
Cd) S, SrGa₂S_Four, SrS, GaS, SnO₂,
Ca_Ten(PO_Four)₆(F, Cl)₂, (Ba, Sr) (M
g, Mn) Al_TenO₁₇, (Sr, Ca, Ba, Mg)_Ten
(PO_Four)₆Cl₂, (La, Ce) PO_Four, CeMgAl
₁₁O₁₉, GdMgB_FiveO_Ten, Sr₂P ₂O₇, Sr_FourAl₁₄
O_{twenty five}, Y₂SO_Four, Gd₂O₂S, Gd₂O₃, YVO_Four, Y
(P, V) O_Fouretc.

The above-mentioned crystal matrix and activator or coactivator may be partially substituted with a homologous element,
The elemental composition is not particularly limited as long as it absorbs light in the ultraviolet region or light in the violet region and emits visible light.

In the present invention, preferred as the activator and co-activator for the inorganic phosphor are La, Eu, Tb and C.
e, Yb, Pr, and other lanthanoid element ions, and metal ions such as Ag, Mn, Cu, In, and Al, with a doping amount of 0.001 to 100 with respect to the base material.
Mol% is preferable, and 0.01 to 50 mol% is more preferable. The activator and co-activator are doped into the crystal by replacing a part of the ions constituting the crystal matrix with an ion such as the lanthanoid.

The actual composition of the phosphor crystal, if rigorously described, has the following composition formula. However, since the size of the activator often does not affect the essential fluorescence characteristics,
Hereinafter, unless otherwise specified, the numerical values of x and y below are not described. For example, Sr ₄ -xAl ₁₄ O ₂₅ : Eu
²⁺ _x is represented by Sr ₄ Al ₁₄ O ₂₅ : Eu ²⁺ in the present invention. The composition formulas of typical inorganic phosphors (inorganic phosphors composed of a crystal matrix and an activator) are shown below, but the present invention is not limited thereto.

(Ba_zMg_1-z)_3-xyAl₁₆O₂₇: Eu
²⁺ _x, Mn²⁺ _y, Sr_4-xAl₁₄O_{twenty five}: Eu²⁺ _x, (Sr
_1-zBa_z)_1-xAl₂Si₂O₈: Eu²⁺ _x, Ba_2-xSiO
_Four: Eu ²⁺ _x, Sr_2-xSiO_Four: Eu²⁺ _x, Mg_2-xSiO
_Four: Eu²⁺ _x, (BaSr)_1-xSiO_Four: Eu²⁺ _x, Y
_2-xySiO_Five: Ce³⁺ _x, Tb³⁺y, Sr_2-xP₂O_Five: E
u²⁺ _x, Sr_2-xP₂O₇: Eu²⁺ _x, (Ba_yCa_zMg
_1-yz)_5-x(PO_Four)₃Cl: Eu²⁺ _x, Sr_2-xSi₃O₈
2SrCl₂: Eu²⁺ _x.

X, y and z each represent an arbitrary number of 1 or less. The inorganic phosphors preferably used in the present invention are shown below, but the present invention is not limited thereto.

<Blue light-emitting / inorganic phosphor> BL-1: Sr ₂ P ₂ O ₇ : Sn ⁴⁺ BL-2: Sr ₄ Al ₁₄ O ₂₅ : Eu ²⁺ BL-3: BaMgAl ₁₀ O ₁₇ : Eu _{^{2+ BL-4: SrGa 2 S}} 4: Ce 3+ BL-5: CaGa 2 S 4: Ce 3+ BL-6: (Ba, Sr) (Mg, Mn) Al 10 O 17:
Eu ²⁺ BL-7: (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ C
^{_{l 2: Eu 2+ BL-8}} : BaAl 2 SiO 8: Eu 2+ BL-9: Sr 2 P 2 O 7: Eu 2+ BL-10: Sr 5 (PO 4) 3 Cl: Eu 2+ BL- 11: (Sr, Ca, Ba) ₅ (PO ₄ ) ₃ Cl:
_{^{Eu 2+ BL-12: BaMg 2}} Al 16 O 27: Eu 2+ BL-13: (Ba, Ca) 5 (PO 4) 3 Cl: Eu 2+ BL-14: Ba 3 MgSi 2 O 8: Eu 2 _{^{+ BL-15: Sr 3 MgSi}} 2 O 8: Eu 2+ < green emitting inorganic phosphor> GL-1: (BaMg) Al 16 O 27: Eu 2+, Mn 2+ GL-2: Sr 4 Al ₁₄ O ₂₅ : Eu ²⁺ GL-3: (SrBa) Al ₂ Si ₂ O ₈ : Eu ²⁺ GL-4: (BaMg) ₂ SiO ₄ : Eu ²⁺ GL-5: Y ₂ SiO ₅ : Ce3 +, Tb. _{^{3+ GL-6: Sr 2 P}} 2 O 7 -Sr 2 B 2 O 5: Eu 2+ GL-7: (BaCaMg) 5 (PO 4) 3 Cl: Eu 2+ GL-8: Sr 2 Si 3 O ^{_{8 -2SrCl 2: Eu 2+ GL-}} 9: Zr 2 SiO 4, MgAl 11 O 19: Ce 3+, T
_{^{b 3+ GL-10: Ba 2}} SiO 4: Eu 2+ GL-11: Sr 2 SiO 4: Eu 2+ GL-12: (BaSr) SiO 4: Eu 2+ GL-13: SrGa 2 S 4: Eu ²⁺ <red emitting inorganic _{phosphor> RL-1: Y 2 O} 2 S: Eu 3+ RL-2: YAlO 3: Eu 3+ RL-3: Ca 2 Y 2 (SiO 4) 6: Eu 3 _{^{+ RL-4: LiY 9 (}} SiO 4) 6 O 2: Eu 3+ RL-5: YVO 4: Eu 3+ RL-6: CaS: Eu 3+ RL-7: Gd 2 O 3: Eu 3+ RL _{-8: Gd 2 O 2 S:} Eu 3+ RL-9: Y (P, V) O 4: Eu 3+ RL-10: Mg 4 GeO 5.5 F: Mn 4+ RL-11: Mg 4 GeO 6: Mn ⁴⁺ inorganic phosphors may be subjected to surface modification treatment if necessary, or by chemical treatment such as a silane coupling agent as a method, submicron By physical treatment by the addition of fine particles of readers, more like due to their combination thereof.

The silane coupling agent used in the present invention is published by Unicar Japan Ltd. (August 2, 1997)
Those described in the "NUC Silicone Silane Coupling Agents" catalog can be used as they are, and specific examples thereof include β- (3,4-epoxycyclohexyl) ethyltrialkoxysilane, glycidyloxyethyltriethoxysilane, γ- Acryloyloxypropyl
Tri-propyloxysilane, γ-methacryloyloxypropyl propyloxysilane, di (γ-acryloyloxypropyl) di-propyloxysilane, acryloyloxydimethoxyethylsilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane , N
-Β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane,
Examples thereof include N-phenyl-γ-aminopropyltrimethoxysilane and γ-mercaptopropyltrimethoxysilane.

The fine particles used in the present invention are preferably inorganic fine particles, and examples thereof include fine particles of silica, titania, zirconia, zinc oxide and the like.

The rare earth complex-based phosphors include Ce, Pr, Nd, Pm, Sm, Eu, Gd and T as rare earth metals.
Examples thereof include those having b, Dy, Ho, Er, Tm, Yb, and the like, and the organic ligand forming the complex may be either an aromatic type or a non-aromatic type, preferably the following general formula (B The compound represented by these is preferable.

General formula (B) Xa- (Lx)-(Ly)
_n- (Lz) -Ya In formula, Lx, Ly, and Lz each independently represent an atom having two or more bonds, n represents 0 or 1, and Xa represents Lx.
Represents a substituent having an atom capable of coordinating to the adjacent position of
Represents a substituent having an atom capable of coordinating to the adjacent position of Lz. Further, any part of Xa and Lx, and any part of Ya and Lz may be condensed with each other to form a ring, or Lx and Lz may be condensed with each other to form a ring,
Furthermore, at least one aromatic hydrocarbon ring or aromatic heterocycle exists in the molecule. However, Xa- (Lx)-(L
y) _n- (Lz) -Ya is a β-diketone derivative, a β-ketoester derivative, a β-ketoamide derivative or the above ketone in which an oxygen atom is replaced by a sulfur atom or —N (R ₂₀₁ ) —, crown ether or aza. In the case of representing a crown ether in which an oxygen atom of a crown ether or a thia crown ether or a crown ether is replaced with an arbitrary number of sulfur atoms or -N ( _R201 )-, there is no aromatic hydrocarbon ring or aromatic heterocycle. Good. Here, R ₂₀₁ represents a hydrogen atom, or a substituted or unsubstituted alkyl group or aryl group.

The coordinable atom represented by Xa and Ya is specifically an oxygen atom, a nitrogen atom, a sulfur atom, a selenium atom or a tellurium atom, and particularly an oxygen atom, a nitrogen atom or a sulfur atom. It is preferable.

The atom having two or more bonds represented by Lx, Ly and Lz is not particularly limited, and typical examples thereof include carbon atom, oxygen atom, nitrogen atom, silicon atom and titanium atom. However, preferred is a carbon atom.

Specific examples of the rare earth complex type phosphor represented by the general formula (B) are shown below, but the invention is not limited thereto.

[0115]

[Chemical 25]

[0116]

[Chemical formula 26]

[0117]

[Chemical 27]

[0118]

[Chemical 28]

[0119]

[Chemical 29]

[0120]

[Chemical 30]

[0121]

[Chemical 31]

Next, the substrate of the device will be described. Organic E
The substrate preferably used for the L element is not particularly limited as to the type of glass, plastic, etc., and is not particularly limited as long as it is transparent. Examples of the substrate preferably used in the present invention include glass, quartz, and a light-transmissive plastic film.

As the light-transmissive plastic film,
For example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether sulfone (PES), polyetherimide, polyether ether ketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC), cellulose Examples thereof include films made of acetate propionate (CAP) and the like.

The organic EL element of the present invention may be used as a kind of lamp for illumination or an exposure light source, or as a display device for reproducing a still image or a moving image. In particular, when used as a display device for reproducing moving images, the drive system may be a simple matrix (passive matrix) system or an active matrix system.

[0125]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, “%” in the examples means “mass%”.

First, the exemplified compounds 101, 124 and 10
An example of the synthesis of 7, 201 and 204 is shown.

Synthesis Example 1 (Synthesis of Compound 101)

[0128]

[Chemical 32]

2,2'-Dimethylbenzidine hydrochloride 1
5.0 g of 47% hydrogen bromide water 100 ml and water 150 ml
It was dissolved in water and cooled to 0 ° C with ice. An aqueous solution prepared by dissolving 8.0 g of sodium nitrite in 20 ml of water was added dropwise to this solution while maintaining the liquid temperature at 0 to 3 ° C. After completion of the dropping, the mixture was stirred for 1 hour (preparation of diazonium salt).

On the other hand, a solution prepared by dissolving 17.0 g of cuprous bromide in 70 ml of 47% hydrogen bromide water was also ice-cooled to 0 °. The solution of the diazonium salt prepared above was added dropwise to this solution while maintaining the liquid temperature at 0 to 5 ° C. Then, after stirring for 30 minutes, the liquid temperature was raised to 80 ° C. and stirring was continued for 3 hours. Then, 100 ml each of tetrahydrofuran and ethyl acetate were added to the reaction solution, and the organic layer was extracted. After drying over magnesium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by column chromatography in which the ratio of ethyl acetate and hexane was 1: 5 to obtain 12.3 g of compound (A-1) (yield 68.
%).

Next, after degassing, under a nitrogen atmosphere, 0.23 g of palladium acetate and 1 ml of tri-t-butylphosphine.
Was dissolved in 50 ml of dehydrated xylene. Then, 3.0 g of A-1, 4.8 g of phenyl.α-naphthylamine, and 2.2 g of sodium-t-butoxide were added, and 120 ° C was added.
The mixture was heated and stirred for 4 hours. Then, tetrahydrofuran, ethyl acetate, and water were added to the reaction solution, the mixture was filtered through diatomaceous earth, and then the organic layer was extracted. After drying over magnesium sulfate, the solvent was distilled off under reduced pressure, the residue was purified by column chromatography with a ratio of toluene to hexane of 1: 7, and recrystallized from toluene to obtain 2.6 g of the target compound 101 (yield). Rate 4
8%). Compound 10 by NMR and mass spectrum
It was confirmed to be 1.

Synthesis Example 2 (Synthesis of Compound 124)

[0133]

[Chemical 33]

Instead of the compound (A-1), 1.62 g of 2,7-dibromofluorene, 2.7 g of phenyl .alpha.-naphthylamine and 1.2 g of sodium t-butoxide were used.
By using 5 g, compound 124 was prepared in the same manner as in Synthesis Example 1.
Was obtained (yield 52%). It was confirmed to be the desired product by NMR and mass spectrum.

Synthesis Example 3 (Synthesis of Compound 107)

[0136]

[Chemical 34]

20 g of 3,5-dimethylnitrobenzene,
50 g of zinc powder was heated in 100 ml of ethanol, and when the mixture was refluxed, the heating was stopped and 100 ml of a 30% aqueous sodium hydroxide solution was added dropwise. When the boiling had subsided, heating was restarted and reflux was continued for 5 hours. After filtering the insoluble matter, 50 ml of ethanol was added to the insoluble matter.
Was added to reflux, and the filtered filtrates were combined and ethanol was distilled off. 100 ml of ethyl acetate and 30% acetic acid were added to the residue.
50 ml of 0.5 M sodium bisulfite aqueous solution was added for liquid separation, and the mixture was washed 3 times with 50 ml of water, and then ethyl acetate was distilled off to obtain 14.0 g of an orange crude product. By further recrystallizing in hexane, 11.0 g of compound (A-2)
Got

11.0 g of the compound (A-2) was dissolved in 500 ml of degassed 10% hydrochloric acid, and the mixture was refluxed for 6 hours. After cooling, the suspended matter was filtered, and a 20% sodium hydroxide solution was added until it became cloudy to neutralize. 200 ml of ethyl acetate was added for extraction, the organic phase was dehydrated with magnesium sulfate, and then ethyl acetate was distilled off to obtain 10.0 g of a reddish purple crude product.
Recrystallization was performed with a hexane: toluene = 2: 1 solution to obtain 7.1 g of a dark red powder (yield 65%). Compound (A-3) by NMR, mass spectrum and amine color reagent
Was confirmed.

3.4 g of the compound (A-3) was dissolved in 30 ml of 10% sulfuric acid, and sodium nitrite 2.1.
A solution of 4 g dissolved in 21 ml of water was added dropwise with stirring. After stirring for 1 hour after dropping, 10% copper (I) bromide-4
Poured into 214 ml of 8% hydrogen bromide solution. Furthermore, it heated at 50 degreeC and stirred for 4 hours. After cooling, ethyl acetate 150m
It was extracted with 1 and dried over magnesium sulfate, then the solvent was distilled off and purified by column chromatography with a ratio of ethyl acetate and hexane of 1: 5 to obtain 2.7 g of compound (A-4) (yield 53%).

After degassing, under nitrogen atmosphere, 0.10 g of palladium acetate and 0.45 ml of tri-t-butylphosphine.
Was dissolved in 15 ml of dehydrated xylene. Then, 0.92 g of compound (A-4), 1.05 g of 3-methyldiphenylamine, and 0.55 g of sodium-t-butoxide were added, and the mixture was heated and stirred at 120 ° C. for 4 hours. Then, tetrahydrofuran, ethyl acetate, and water were added to the reaction solution, the mixture was filtered through diatomaceous earth, and then the organic layer was extracted. After drying over magnesium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by column chromatography with a toluene / hexane ratio of 1: 7.
Recrystallize with toluene to obtain 0.7 of the desired compound 107.
9 g was obtained (yield 49%). The compound was confirmed to be the target compound by NMR and mass spectrum.

Synthesis Example 4 (Synthesis of Compound 201)

[0142]

[Chemical 35]

0.42 g of 2,2'-dimethylbenzidine
And 1-bromonaphthalene 2.38 g, sodium t-butoxy 1.10 g, palladium acetate 200 mg, tri (t-butyl) phosphine 0.9 ml, dehydrated xylene 3
0 ml was put into a 200 ml flask and refluxed for 5 hours.
After the reaction is completed, 30 ml of tetrahydrofuran is added to the reaction solution,
The suspended matter in the reaction solution containing 30 ml of water was removed by filtration. The filtrate was separated and further washed twice with 30 ml of water. The organic layer was dehydrated with magnesium sulfate and then distilled off to obtain a brown crude product. This was purified by silica gel column chromatography to obtain 0.75 g of compound 201 (yield 50%). It was confirmed to be the desired product by NMR and mass spectrum.

Synthesis Example 5 (Synthesis of Compound 204)

[0145]

[Chemical 36]

After degassing, 0.16 g of palladium acetate and 0.7 ml of tri-t-butylphosphine were dissolved in 15 ml of dehydrated xylene under a nitrogen atmosphere. Thereafter, 0.96 g of the compound (A-3), 4.1-iodonaphthalene 4.1
7 g and 1.58 g of sodium-t-butoxide were added, and the mixture was heated and stirred at 120 ° C. for 4 hours. Then, tetrahydrofuran, ethyl acetate, and water were added to the reaction solution, the mixture was filtered through diatomaceous earth, and then the organic layer was extracted. After drying over magnesium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by column chromatography in which the ratio of toluene to hexane was 1: 7, and then recrystallized from toluene to obtain 1.22 of the target compound 204.
g was obtained (41% yield). It was confirmed by NMR and mass spectra that the compound of interest was (204).

Example 1 As an anode, 150 (ITO) indium tin oxide was formed on a glass substrate of 100 mm × 100 mm × 1.1 mm.
Substrate with nm film (NH-45 manufactured by NH Techno Glass Co., Ltd.)
After patterning, the transparent support substrate provided with this ITO transparent electrode was ultrasonically cleaned with i-propyl alcohol, dried with dry nitrogen gas, and UV ozone cleaned for 5 minutes.

This transparent support substrate was fixed to a substrate holder of a commercially available vacuum evaporation system, while 200 mg of m-MTDATXA was put into a resistance heating boat made of molybdenum, and the comparative compound (1) was put in another resistance heating boat made of molybdenum. 20
0 mg was put, 200 mg of vascuproin (BC) was put into another molybdenum resistance heating boat, and it was attached to a vacuum vapor deposition apparatus. Next, after depressurizing the vacuum chamber to 4 × 10 ⁻⁴ Pa, the heating boat containing m-MTDATXA was energized to heat up to 220 ° C., and the vapor deposition rate was 0.1 to 10.
Deposition at a thickness of 33 nm on a transparent support substrate at 0.3 nm / sec.
nm hole transport layer was provided. Further, the heating boat containing the comparative compound (1) is energized to heat to 220 ° C.,
A light emitting layer having a film thickness of 33 nm was provided by vapor deposition on the hole transport layer at a vapor deposition rate of 0.1 to 0.3 nm / sec. The substrate temperature during vapor deposition was room temperature. Further, the heating boat containing BC is energized and heated to 250 ° C., and vapor-deposited on the light-emitting layer at a vapor deposition rate of 0.1 nm / sec to form a film having a thickness of 3
An electron injection layer of 3 nm was provided. The substrate temperature during vapor deposition was room temperature.

Next, the vacuum chamber was opened and a rectangular perforated mask made of stainless steel was placed on the electron injection layer, while 3 g of magnesium was placed in a molybdenum resistance heating boat.
0.5 g of silver was placed in a tungsten vapor deposition basket, the vacuum chamber was decompressed again to 2 × 10 ⁻⁴ Pa, and a boat containing magnesium was energized to deposit a vapor deposition rate of 1.5 to 2.
Magnesium is vapor-deposited at 0 nm / sec, and at the same time, a silver basket is heated at a vapor deposition rate of 0.1 nm / se.
A comparative organic EL element 1-1 was prepared by vapor-depositing silver with c to form a counter electrode made of the mixture of magnesium and silver. M-MTDATX used above
The structures of A, BC and comparative compound (1) are shown below.

[0150]

[Chemical 37]

In the above, comparative compound (1) for the light emitting layer
Comparative organic EL devices 1-2 to 1-6 and organic EL devices 1-7 to 1-14 of the invention were prepared by the same method except that the compounds shown in Table 1 were replaced. Comparative Organic E
Comparative compound (2) used for L element 1-2 to 1-6
The structure of (6) is shown below. Among them, the comparative compound (6) is one of the compound examples disclosed in JP-A No. 11-312586.

[0152]

[Chemical 38]

With respect to the organic EL elements 1-1 to 1-10, the maximum radiant energy and the emission lifetime were measured and evaluated using the ITO electrode of the element as an anode and the counter electrode made of magnesium and silver as a cathode.

In the comparative organic EL elements 1-1 to 1-5,
Blue or purple-blue light emission from the compound of the light emitting layer was observed. In the organic EL device 1-6, yellow-green light emission was observed, probably because it forms an exciplex with BC of the electron transport layer. Also, because of this, the light emission life was short. On the other hand, in the organic EL device 1-7 of the present invention, a current started to flow at an initial drive voltage of 5 V, and bluish-violet light was emitted from the compound of the light emitting layer. 6 W / Sr · at maximum radiant energy of 9 V
It was m ² . Table 1 shows the value (relative value) of the ratio of the maximum radiant energy of each organic EL device sample when the maximum radiant energy of 1-7 is 100.

As a result of performing a life test on the element 1-7 in a nitrogen gas atmosphere, the initial radiant energy was 1 W / Sr.
The half-life of · m ² was 1160 hours. The values (relative values) of the emission lifetime ratios of the respective organic EL element samples when the emission lifetime of the organic EL elements 1-7 is set to 100 are also shown in Table 1.
Shown in.

[0156]

[Table 1]

As is clear from Table 1, the electroluminescence device using the compound of the present invention in the light emitting layer has high maximum luminance and long light emission life.
It turned out to be very useful as a device.

Since the luminosity differs greatly depending on the color of the light emitted, the comparison is made not with the luminance but with the radiant energy.

Example 2 Organic electroluminescence device 2-1 was prepared in the same manner as in Example 1 except that the compound used for the light emitting layer was DMPhen and the compound used for the hole transport layer was the compound shown in Table 2. ~ 2-13 were prepared.

[0160]

[Chemical Formula 39]

In the comparative organic EL elements 2-1 to 2-5,
Blue or purple-blue light emission from the compound of the hole transport layer was observed. In the organic EL element 2-6, the DMPh of the light emitting layer
Yellow-green luminescence was observed, probably due to the formation of an exciplex with en. Also, because of this, the light emission life was short.

In the organic EL device 2-7 of the present invention, a current started to flow at an initial drive voltage of 5 V, and bluish purple emission was exhibited.
17 W / Sr · at maximum radiant energy of 11 V
It was m ² . Table 2 shows the value (relative value) of the ratio of the maximum radiant energy of each organic EL device sample when the maximum radiant energy of 2-7 is 100.

Further, as a result of performing a life test on the device of No. 2-1 in a nitrogen gas atmosphere, the initial radiant energy was 1 W / Sr.
-The half-life of m ² was 380 hours. The light emission lifetime of the other elements is shown in Table 2 as a relative value when the value of the organic EL element 2-1 is 100.

[0164]

[Table 2]

As is clear from Table 2, the electroluminescence device using the compound of the present invention in the hole transport layer has a high maximum luminance and a long emission life, and is therefore very useful as an organic EL device. It has been found.

Example 3 It carried out about the organic EL element with a color conversion filter.

(Preparation of Color Conversion Filter Using Inorganic Phosphor) 15 g of ethanol and 0.22 g of γ-glycidoxypropyltriethoxysilane were added to 0.16 g of Aerosil having an average particle size of 5 nm, and the temperature was maintained at room temperature in an open system. It was stirred for 1 hour. This mixture and 20 g of (RL-10) were transferred to a mortar and mixed well, and then in an oven at 70 ° C. for 2 hours,
Further, it was heated in an oven at 120 ° C. for 2 hours to obtain a surface-modified (RL-10). Similarly, (GL-13),
The surface of (BL-3) was also modified.

(RL-10) 1 which has been subjected to the above surface modification
To 0 g, a mixed solution of toluene / ethanol = 1/1 (3
Then, 30 g of butyral (BX-1) dissolved in 00 g) was added, stirred, and then coated on glass with a wet film thickness of 200 μm. The obtained coated glass is heated and dried in an oven at 100 ° C. for 4 hours to obtain the color conversion filter (F
-R) was prepared. Also, in the same way as this (GL-
3), a color conversion filter (F-
G) and (FB) were produced.

Organic EL Element 1-Manufactured in Examples 1 and 2
On the substrates 1 to 1-14 and 2-1 to 2-14, a color conversion filter (FB) as a blue conversion layer, a color conversion filter (FG) as a green conversion layer, and a color as a red conversion layer. Conversion filters (F-R) were applied at intervals of 1.5 mm to produce organic EL elements 3-1 to 3-28.

For each of the organic EL elements 3-1 to 3-20,
Applying a DC voltage of 9 V in a dry nitrogen gas atmosphere at a temperature of 23 ° C., the emission brightness of each of blue, green, and red, the time for which the brightness is halved,
And chromaticity coordinates were measured using Minolta CS-1000.

Comparative organic EL elements 3-1 to 6 and 15 to 2
In 0, the light emission from the organic EL element was blue and did not match the absorption of the phosphor, or the light emission was weak, and thus the color conversion efficiency into blue, green, and red was low. On the other hand, in the organic EL elements 3-7 to 14 and 21 to 28 of the present invention, the phosphor is excited by the blue-violet emission from the organic EL element, and blue, green, and
High color conversion efficiency to red was achieved. The maximum ultimate brightness of each element, the emission life is the maximum ultimate brightness of the organic EL element 3-7,
It was expressed as a relative value when the emission lifetime was 100.

The results are shown in Tables 3 and 4.

[0173]

[Table 3]

[0174]

[Table 4]

As is clear from Table 3, the electroluminescent device of the present invention has been found to be extremely useful as an organic EL device since it has a maximum brightness and a long emission life.

[0176]

According to the present invention, it is possible to obtain a high-luminance and long-life organic EL device which emits light of blue-violet to near-ultraviolet.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of the configuration of an organic electroluminescence element of the present invention.

[Explanation of symbols]

1 cathode 2 Electron transport layer 3 light emitting layer 4 Hole transport layer 5 anode 6 glass substrates 7R Red conversion layer 7G green conversion layer 7B blue conversion layer

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09K 11/06 635 C09K 11/06 635 645 645 645 650 650 655 655 H05B 33/12 H05B 33/12 E 33/14 33 / 14 B 33/22 33/22 DF term (reference) 3K007 AB02 AB04 AB11 CA01 CB01 DA01 DB03 EB00 4C034 AA00 AA10 4H006 AA01 AB92

Claims (12)

[Claims] 1. A compound represented by the following general formula (1): [Chemical 1] [In the formula, at least one of T _{1 to} T ₄ is a substituent, and R _{1 to} R ₁₄ each represent a hydrogen atom or a substituent, and
r ₁ and Ar ₂ each represent an aromatic group which may have a substituent, but at least one of Ar ₁ and Ar ₂ is a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, a 9-anthryl group. A group, a 1-pyrenyl group, a 2-pyrenyl group or an aromatic heterocyclic group. ] 2. The compound according to claim 1, wherein in the general formula (1), all of T _{1 to} T ₄ are substituents. 3. In the general formula (1), R _{1 to} R ₁₄
Is a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, a dialkylamino group or a diarylamino group, respectively. 4. A compound represented by the following general formula (2). [Chemical 2] [In the formula, at least one of T _{5 to} T ₈ is a substituent, and R _{15 to} R ₁₈ each represent a hydrogen atom or a substituent, and
r _{3 to} Ar ₆ each represent an aromatic group which may have a substituent, but at least one of Ar _{3 to} Ar ₆ is a 1-naphthyl group,
It is a 2-naphthyl group, a 1-anthryl group, a 9-anthryl group, a 1-pyrenyl group, a 2-pyrenyl group or an aromatic heterocyclic group. ] 5. The compound according to claim 4, wherein in the general formula (2), all of T _{5 to} T ₈ are substituents. 6. In the general formula (2), R _{15 to} R ₁₈
Is a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, a dialkylamino group or a diarylamino group, respectively. 7. An organic electroluminescence device material containing the compound according to any one of claims 1 to 6. 8. An organic electroluminescence device comprising the device material according to claim 7. 9. An organic electroluminescence device comprising the compound according to claim 1 in a light emitting layer. 10. An organic electroluminescent device comprising the hole transport layer containing the compound according to claim 1. Description: 11. A Purlish of CIE chromaticity coordinates.
The organic electroluminescence device according to claim 8, 9 or 10, which emits light in a region of Blue (purple blue), Blue Purple (purple) or Purple (purple). 12. The electroluminescent light emission of the compound is absorbed to obtain 400 to 500 nm and 50, respectively.
9. At least one conversion layer containing at least one inorganic compound having a maximum emission wavelength within the range of 1 to 600 nm and 601 to 700 nm is provided.
11. The organic electroluminescence device according to any one of 1 to 11.