JP2003020477A - Material for organic electroluminescent element and organic electroluminescent element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emiting material for an organic EL element having luminescent colors from yellow to red, and having high emission brightness and a long emission life, and to provide an organic EL element using the light emitting material. SOLUTION: The material for an organic electroluminescent element is expressed by the general formula [1] (wherein, Ar<1> is a monovalent organic residue containing a monocyclic ring or a condensed polycyclic ring; Ar<2> is a divalent organic residue containing a monocyclic ring or a condensed polycyclic ring; R<1> to R<8> are each independently H, cyano or the like, and at least one of R<5> and R<6> is cyano; and n and m are each an integer of 0-10).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting material for an organic electroluminescence (EL) element used for a flat light source or a display and a high brightness light emitting element.

[0002]

2. Description of the Related Art An EL element using an organic substance is expected to be used as a solid-state light emitting type inexpensive large area full color display element, and many developments have been made. Generally, an EL element is composed of a light emitting layer and a pair of counter electrodes sandwiching the light emitting layer. In light emission, when an electric field is applied between both electrodes, electrons are injected from the cathode side, holes are injected from the anode side, the electrons recombine with the holes in the light emitting layer, and the energy level changes from the conduction band. This is a phenomenon in which energy is emitted as light when returning to the valence band.

A conventional organic EL element has a higher driving voltage and lower emission brightness and emission efficiency than an inorganic EL element.
In addition, the deterioration of the characteristics was remarkable and it was not put to practical use.
In recent years, an organic EL in which thin films containing an organic compound having a high fluorescence quantum efficiency that emits light at a low voltage of 10 V or less are laminated
The device has been reported and is of great interest (see Applied Physics Letters, 51, 913, 1987). This method uses a metal chelate complex as a light emitting layer and an amine compound as a hole injecting layer to obtain high-intensity green light emission, and a direct current voltage of 6 to 7 V produces a brightness of several thousand c.
d / m ² , maximum luminous efficiency of 1.5 lm / W is achieved,
It has a performance close to the practical range.

Particularly, as a light emitting material for an organic EL device for obtaining yellow to red light emission, as an electron transporting material,
Tris (8-quinolinol) aluminum (hereinafter Alq
3) and DCM (4-dicyanomethylene-6- (p
-Dimethylaminostyryl) -2-methyl-4H-pyrazine) -doped orange emission (Chem.Funcl.Dyes.Pr)
oc.Int.Symp., 2nd 536 pages 1993), etc., but it is not satisfactory as a display material in terms of maximum brightness and color purity, and it is desired to realize a red light emitting device with higher brightness and good color purity. Is the current situation.

[0005]

However, although the organic EL devices to date have been improved in the emission brightness due to the improved structure, they still do not have sufficient emission brightness. Further, it has a big problem that it is inferior in stability when repeatedly used. This is because, for example, a metal chelate complex such as a tris (8-hydroxyquinolinato) aluminum complex is chemically unstable during electroluminescence, has poor adhesion to the cathode, and is greatly deteriorated by light emission in a short time. Was there. For the above reasons, in order to develop an organic EL element having high emission brightness and emission efficiency and excellent stability in repeated use, development of a light emitting material having excellent emission ability and durability Is desired.

Further, Japanese Patent Application Laid-Open No. 6-207170 proposes to use a specific styryl compound as an organic electroluminescent material. However, the intended luminescent color is blue, and the cyano group is not used for red. Japanese Patent Laid-Open No. 7-987
Also in the 87 publication, the emission color is from blue to green.

The present invention is an organic E having a high emission brightness and a long emission life while having emission colors from yellow to red.
A light emitting material for an L element and an organic EL element using the same. As a result of diligent studies by the present inventors, the use of a styryl compound having a specific chemical structure represented by the general formula [1] as a light emitting material causes the organic EL device to emit yellow to red light, and thus the emission brightness and the light emission. High efficiency,
It has been found that the light emission life is also excellent.

[0008]

The present invention relates to a material for an organic electroluminescence device represented by the following general formula [1]. General formula [1]

[0009]

[Chemical 2]

[In the formula, Ar ¹ represents a monovalent organic residue containing a monocyclic ring or a condensed polycyclic ring, Ar ² represents a divalent organic residue containing a monocyclic ring or a condensed polycyclic ring, R 2 ^{1 to} R ⁸ each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and at least one of R ^{5 and} R ⁶ is a cyano group. A ring may be formed between R ¹ or R ² and Ar ² . n and m are integers from 0 to 10. The present invention also provides an organic electroluminescent device comprising a light emitting layer or a plurality of organic compound thin films including a light emitting layer formed between a pair of electrodes, wherein any one of the layers is a material for the organic electroluminescent device. It is an organic electroluminescent element characterized by containing a single or a mixture.

Further, the present invention is an organic electroluminescence device comprising a light emitting layer or a plurality of organic compound thin films including a light emitting layer formed between a pair of electrodes, wherein the light emitting layer is made of the above-mentioned material for organic electroluminescence device alone. Alternatively, it is an organic electroluminescent device characterized by being contained as a mixture.

Further, the present invention is the above-mentioned organic electroluminescence device, further comprising a hole injection layer formed between the anode and the light emitting layer.

Further, the present invention is the above-mentioned organic electroluminescent device, further comprising an electron injection layer formed between the cathode and the light emitting layer.

Further, the present invention is the above-mentioned organic electroluminescent device, wherein the electron injection layer is a layer containing a metal complex compound or a nitrogen-containing aromatic ring compound.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION That is, the present invention relates to an organic electroluminescence device, wherein an organic layer having a light emitting region is provided between an anode and a cathode, and an organic substance which emits light when an electric current is injected is contained as a component. The organic layer contains a novel distyryl compound represented by the general formula [1] as an organic light emitting material.

In the compound represented by the general formula [1] in the present invention, Ar ¹ represents a monovalent organic residue containing a monocycle or a condensed polycycle, and Ar ² contains a monocycle or a condensed polycycle. Represents a divalent organic residue, R ^{1 to} R ⁸ each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group,
At least one of R ^{5 and} R ⁶ is a cyano group. R ¹
Alternatively, a ring may be formed between R ² and Ar ² . n, m
Is an integer from 0 to 10.

Specific examples of the monocyclic group include a monocyclic cycloalkyl group, a monocyclic aryl group and a monocyclic heterocyclic group.

The monocyclic cycloalkyl group includes cycloalkyl groups such as cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group and cyclooctyl group.

The monocyclic aryl group includes a phenyl group.

As the monocyclic heterocyclic group, thienyl group, furyl group, pyrrolyl group, imidazolyl group, pyrazolyl group, pyridinyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, triazinyl group, triazolyl group, oxazolyl group, thiazolyl group, Examples include an oxadiazolyl group, a thiadiazolyl group, and an imidazoliazolyl group.

Examples of the substituted or unsubstituted condensed polycyclic group include condensed polycyclic aryl group, condensed polycyclic heterocyclic group, condensed polycyclic cycloalkyl group and the like.

Examples of the condensed polycyclic aryl group include a naphthyl group, anthryl group, phenanthryl group, fluorenyl group, acenaphthyl group, azulenyl group, heptanenyl group,
Examples thereof include a pyrenyl group, a perynyl group and a triphenylenyl group.

Examples of the condensed polycyclic heterocyclic group include indolyl group, quinolyl group, isoquinolyl group, phthalazinyl group, quinoxalinyl group, quinazolinyl group, carbazolyl group, acridinyl group, phenazinyl group, benzofuryl group, isothiazolyl group, isoxazolyl group and flazanyl group. , Phenoxazinyl group, benzothiazolyl group, benzoxazolyl group, benzimidazolyl group, benzotriazolyl group, pyranyl group and the like. As other condensed polycyclic group,
1-tetralyl group, 2-tetralyl group, tetrahydroquinolyl group and the like.

Further, the above monocyclic group or condensed polycyclic group is
You may connect via the non-aromatic ring structural unit which consists of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom.

The non-aromatic ring structural unit composed of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom and a sulfur atom has a valence of 2 or more, is linear, branched or cyclic, and may not contain an aromatic ring. . Preferably, it has 1 to 40 atoms. Examples of the non-aromatic ring structural unit include an oxygen atom, a sulfur atom, an alkyl group, an alkylene group, an alkyloxy group, an alkylthio group, a cycloalkyl group, an amino group,
Examples thereof include residues such as alkylamino groups.

When the aromatic ring structural units are linked directly or via a non-aromatic ring structural unit, the number of aromatic ring structural units is 2 to 10, and they may be bonded at two or more positions. Furthermore, at least one of the aromatic ring structural units may be a condensed aromatic ring or a condensed heteroaromatic ring, and may have a bond between a single ring and a condensed ring.

The aromatic ring structural unit may be substituted with an alkyl group or the like.

Specifically, examples of direct bonding of two or more aromatic ring structural units include binaphthyl, biquinoline, flavone, phenyltriazine, bisbenzothiazole,
Bithiophene, phenylbenzotriazole, phenylbenzimidazole, phenylacridine, bis (benzoxazolyl) thiophene, bis (phenyloxazolyl) benzene, biphenylylphenyloxadiazole, diphenylbenzoquinone, diphenylisobenzofuran, diphenylpyridine, stilbene, Dibenzyl,
Examples thereof include residues having a skeleton of diphenylmethane, bis (phenylisopropyl) benzene, diphenylfluorene, diphenylhexafluoropropane.

Examples of two or more aromatic ring structural units bonded via a non-aromatic ring structural unit include dibenzylnaphthylketone, dibenzylidenecyclohexanone, distyrylnaphthalene, (phenylethyl) benzylnaphthalene, diphenylether, Methyldiphenylamine,
Benzophenone, phenyl benzoate, diphenylurea,
Diphenyl sulfide, diphenyl sulfone, diphenoxybiphenyl, bis (phenoxyphenyl) sulfone, bis (phenoxyphenyl) propane, diphenoxybenzene, ethylene glycol diphenyl ether,
Examples thereof include residues having a skeleton of neopentyl glycol diphenyl ether, dipicolylamine, and dipyridylamine. .

Preferably, a condensed aromatic ring group having 10 to 40 carbon atoms, or at least one 10 to 10 carbon atoms.
Aromatic ring structural units 2-1 containing 40 fused aromatic rings
0 is a group directly linked. Specific examples thereof include naphthalene, anthracene, phenanthrene, fluorene, pyrene, chrysene, naphthacene, pentacene, perylene, azulene, coronene, rubicene, decacyclene, 1,1-
Examples include binaphthalene and 9,9-bianthracene.

Specific examples of the substituent which may be substituted for Ar ¹ and Ar ^{2 in} the structural formula represented by the general formula [1] in the present invention include, as the halogen atom, fluorine, chlorine, bromine, iodine, substituted or unsubstituted. As the substituted alkyl group, a methyl group, an ethyl group, a propyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a stearyl group, a 2-phenylisopropyl group, Trichloromethyl group, trifluoromethyl group, benzyl group, α-phenoxybenzyl group, α, α
-Dimethylbenzyl group, α, α-methylphenylbenzyl group, α, α-ditrifluoromethylbenzyl group, triphenylmethyl group, α-benzyloxybenzyl group and the like. As the substituted or unsubstituted alkoxyl group,
Methoxy group, ethoxy group, propoxy group, n-butoxy group, t-butoxy group, n-octyloxy group, t-octyloxy group, 1,1,1-tetrafluoroethoxy group, phenoxy group, benzyloxy group, octyl There are phenoxy groups and the like. The substituted or unsubstituted aryl group includes a phenyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a biphenyl group, a 4-methylbiphenyl group and a 4-ethylbiphenyl group. Group, 4-cyclohexylbiphenyl group, terphenyl group, 3,5-dichlorophenyl group, naphthyl group, 5-methylnaphthyl group, anthryl group, pyrenyl group and the like. Examples of the substituted or unsubstituted amino group include an amino group, a dimethylamino group, a diethylamino group, a phenylmethylamino group, a diphenylamino group, a ditolylamino group and a dibenzylamino group. Substituted or unsubstituted cyclopentene ring, cyclohexene ring, phenyl ring, naphthalene ring, anthracene ring, pyrene ring, fluorene ring, furan ring, thiophene ring, or pyrrole ring, which are bonded to each other with adjacent substituents. , Oxazole ring, thiazole ring, imidazole ring, pyridine ring, pyrazine ring, pyrroline ring, pyrazoline ring, indole ring, quinoline ring, quinoxaline ring, xanthene ring, carbazole ring, acridine ring, phenanthroline ring, etc. good.

R represented by the general formula [1] in the present invention
^{1 to} R ⁸ each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, and at least one of R ^{5 and} R ⁶ is a cyano group. A ring may be formed between R ¹ or R ² and Ar ² . Specific examples thereof include a substituted or unsubstituted alkyl group, a methyl group, an ethyl group, a propyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, Stearyl group, 2-phenylisopropyl group, trichloromethyl group, trifluoromethyl group, benzyl group,
α-phenoxybenzyl group, α, α-dimethylbenzyl group, α, α-methylphenylbenzyl group, α, α-ditrifluoromethylbenzyl group, triphenylmethyl group,
There is an α-benzyloxybenzyl group and the like. The substituted or unsubstituted aryl group includes a phenyl group, a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a biphenylyl group, a 4-methylbiphenylyl group, and a 4-ethyl group. Biphenyl group, 4-cyclohexylbiphenylyl group, terphenylyl group, 3,
There are a 5-dichlorophenyl group, a naphthyl group, a 5-methylnaphthyl group, an anthryl group, a pyrenyl group and the like. Substituted or unsubstituted cyclopentene ring, cyclohexene ring, benzene ring, naphthalene ring, anthracene ring, pyrene ring, fluorene ring, furan ring, thiophene ring, or pyrrole ring, which are bonded to each other with adjacent substituents. , Oxazole ring, thiazole ring, imidazole ring, pyridine ring, pyrazine ring, pyrroline ring, pyrazoline ring, indole ring, quinoline ring, quinoxaline ring, xanthene ring, carbazole ring, acridine ring, phenanthroline ring, etc. good.

The compound of the present invention has strong fluorescence not only in solution but also as an individual, and is useful as a fluorescent material whose fluorescence color is from yellow to red. Moreover, since the glass transition point and the melting point are high, the resistance (heat resistance) to Joule heat generated in the organic layer during the electroluminescence, between the organic layers, or between the organic layer and the metal electrode is improved.
When it is used as a device material, it exhibits high emission brightness and is advantageous even when emitting light for a long time.

Further, an ethenyl group containing a cyano group and Ar
It is also possible to adjust the maximum emission wavelength to a longer wavelength side by introducing n or m substituted or unsubstituted ethenyl groups between the ^two .

Two general synthetic methods of the compound of the present invention are shown below.

In the first method, the compound represented by the general formula [2] and a substituted or unsubstituted monocyclic compound or a substituted or unsubstituted condensed polycyclic compound compound in a formyl substitution product are treated with a high-boiling alcohol, The target compound can be synthesized by dehydration condensation using a base as a catalyst. As the high boiling point solvent, n-propanol, i-propanol, n-butanol, tert-butanol, n
-Pentyl alcohol, iso-pentanol and the like. Examples of the base include piperidine, DBU and the like. General formula [2]

[0037]

[Chemical 3]

[Wherein Ar ² , R ¹ , R ² , R ³ , R ⁴ , m
Is equivalent to Ar ² , R ¹ , R ² , R ³ , R ⁴ and m in the general formula [1]. As the second method, at least one compound represented by the general formula [3] and at least one compound represented by the general formula [4] are dehydrated and condensed in a high boiling alcohol using a base as a catalyst. By doing so, the target compound can be synthesized. Examples of the high boiling point solvent include n-propanol, i-propanol, n-butanol, tert-butanol, n-pentyl alcohol, and iso-pentanol. Examples of the base include piperidine, DBU and the like. The above synthesis method is an example and is not particularly limited. General formula [3]

[0039]

[Chemical 4]

[Wherein Ar ² , R ¹ , R ² , R ³ , R ⁴ ,
R ⁵ and m are Ar ² , R ¹ , R ² and R ³ of the general formula [1],
It is equivalent to R ⁴ , R ⁵ and m. ] General formula [4]

[0041]

[Chemical 5]

[0042] [In the formula, ^{Ar 1, R 7, R 8} , n is equivalent to ^{Ar 1, R 7, R 8} , n in the general formula [1]. Hereinafter, typical examples of the compound of the present invention will be specifically illustrated in Table 1, but the present invention is not limited to these typical examples. Table 1

[0043]

[Table 1]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

The compound of the present invention is a compound having strong fluorescence in the solid state and is excellent in electroluminescence. Further, since it has both excellent electron injecting property and electron transporting property from the metal electrode, it can be effectively used as a light emitting material, and further, other hole transporting material, electron transporting material or It does not matter if a doping material is used.

The organic EL element is an element in which a single-layer or multi-layer organic thin film is formed between the anode and the cathode. In the case of the single layer type, a light emitting layer is provided between the anode and the cathode. The light emitting layer contains a light emitting material, and may further contain a hole injecting material or an electron injecting material for transporting holes injected from the anode or electrons injected from the cathode to the light emitting material. However, the luminescent material of the present invention is
Since it is possible to form a uniform thin film having extremely high emission quantum efficiency, high hole transporting ability and electron transporting ability, it is also possible to form a light emitting layer using only the light emitting material of the present invention. The multilayer type is (anode / hole injection zone / emission layer / cathode), (anode / emission layer / electron injection zone / cathode),
(Anode / hole injection zone / light emitting layer / electron injection zone / cathode)
There is an organic EL element laminated in a multilayer structure. Since the compound of the present invention has high emission characteristics and has hole injecting property, hole transporting property, electron injecting property, and electron transporting property,
It can be used as a light emitting material in a light emitting layer.

In the light emitting layer, if necessary, in addition to the compound of the present invention, further known light emitting materials, doping materials, hole injecting materials and electron injecting materials can be used. When the organic EL element has a multi-layered structure, it is possible to prevent deterioration in brightness and life due to quenching.
If necessary, a light emitting material, a doping material, a hole injecting material, and an electron injecting material can be used in combination. Further, by using the doping material, it is possible to improve emission brightness and emission efficiency and obtain red and blue emission. Also,
The hole injecting zone, the light emitting layer, and the electron injecting zone may each be formed by a layer structure of two or more layers. In that case, in the case of the hole injection zone, the layer that injects holes from the electrode is the hole injection layer, and the layer that receives holes from the hole injection layer and transports the holes to the light emitting layer is the hole transport layer. Call. Similarly, in the case of the electron injection zone, the layer that injects electrons from the electrode is called an electron injection layer, and the layer that receives electrons from the electron injection layer and transports the electrons to the light emitting layer is called an electron transport layer. Each of these layers is selected and used according to factors such as the energy level of the material, heat resistance, and adhesion to the organic layer or the metal electrode.

As the light emitting material or the doping material which can be used in the light emitting layer together with the compound of the present invention, anthracene, naphthalene, phenanthrene, pyrene, tetracene, coronene, chrysene, fluorescein, perylene,
Phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene,
Tetraphenyl butadiene, coumarin, oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, quinoline metal complex, aminoquinoline metal complex, benzoquinoline metal complex, imine, diphenylethylene, vinylanthracene, diaminocarbazole, pyran , Thiopyran, polymethine, merocyanine, imidazole chelated oxinoid compounds, quinacridone, rubrene, and dyes such as fluorescent dyes for laser and whitening, but not limited to these.

The abundance ratio of the compound of the present invention and the above compound that can be used together in the light emitting layer in the light emitting layer may be any of the main components. That is, by the respective combinations of the above compounds and the compound of the present invention, the compound of the present invention can be a main material forming a light emitting layer or a dope pink material in another main material.

The hole-injecting material has a capability of transporting holes, has a hole-injecting effect from the anode and an excellent hole-injecting effect to the light-emitting layer or the light-emitting material, and is produced in the light-emitting layer. Examples thereof include compounds that prevent excitons from moving to the electron injection zone or the electron injection material and have excellent thin film forming ability. Specifically, phthalocyanine derivative, naphthalocyanine derivative, porphyrin derivative, oxazole, oxadiazole, triazole, imidazole, imidazolone, imidazolethione, pyrazoline, pyrazolone,
Tetrahydroimidazole, oxazole, oxadiazole, hydrazone, acylhydrazone, polyarylalkane, stilbene, butadiene, benzidine type triphenylamine, styrylamine type triphenylamine, diamine type triphenylamine, and their derivatives, and polyvinylcarbazole. Polymer materials such as polysilane and conductive polymers are available, but are not limited thereto.

Among the hole injection materials that can be used in the organic EL device of the present invention, the more effective hole injection material is
An arylamine derivative, a phthalocyanine compound or a triphenylene derivative. Specific examples of the arylamine derivative include triphenylamine, tritolylamine, tolyldiphenylamine, N, N′-diphenyl-
N, N'-di-m-tolyl-4,4'-biphenyldiamine, N, N, N ', N'-tetra (p-tolyl) -p
-Phenylenediamine, N, N, N ', N'-tetra-
p-tolyl-4,4'-biphenyldiamine, N, N '
-Diphenyl-N, N'-di (1-naphthyl) -4,
4'-biphenyldiamine, N, N'-di (4-n-butylphenyl) -N, N'-di-p-tolyl-9,10
-Phenanthrene diamine, 4,4 ', 4 "-tris (N-phenyl-Nm-tolylamino) triphenylamine, 1,1-bis [4- (di-p-tolylamino)
Examples thereof include, but are not limited to, phenyl] cyclohexane and the like, and oligomers and polymers having these aromatic tertiary amine skeletons.

Specific examples of the phthalocyanine (Pc) compound include H ₂ Pc, CuPc, CoPc, NiPc and Z.
nPc, PdPc, FePc, MnPc, ClAlP
c, ClGaPc, ClInPc, ClSnPc, Cl
₂ SiPc, (HO) AlPc, (HO) GaPc, V
OPc, TiOPc, MoOPc, GaPc-O-Ga
There are phthalocyanine derivatives such as Pc and naphthalocyanine derivatives, but not limited to these.

Specific examples of the triphenylene derivative include:
Hexamethoxytriphenylene, hexaethoxytriphenylene, hexahexyloxytriphenylene, hexabenzyloxytriphenylene, trimethylenedioxytriphenylene, hexaalkoxytriphenylenes such as triethylenedioxytriphenylene, hexaphenoxytriphenylene, hexanaphthyloxytriphenylene, hexabiphenylyloxytriphenylene ,
Examples thereof include, but are not limited to, hexaaryloxytriphenylenes such as triphenylene dioxytriphenylene, hexaacyloxytriphenylenes such as hexaacetoxytriphenylene, and hexabenzoyloxytriphenylene.

The electron injecting material has an ability to transport electrons, has a hole injecting effect from the cathode, and an excellent electron injecting effect to the light emitting layer or the light emitting material. Examples thereof include compounds that prevent migration to the hole injection zone and have excellent thin film forming ability. For example, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole,
Triazole, imidazole, perylene tetracarboxylic acid, fluorenylidene methane, anthraquinodimethane,
Examples include, but are not limited to, anthrone and derivatives thereof. It is also possible to sensitize the hole injecting material by adding an electron accepting substance and the electron injecting material by adding an electron donating substance.

In the organic EL device of the present invention, a more effective electron injection material is a metal complex compound or a nitrogen-containing five-membered ring derivative. Specifically, metal complex compounds include 8-hydroxyquinolinato lithium and bis (8
-Hydroxyquinolinato) zinc, bis (8-hydroxyquinolinate) copper, bis (8-hydroxyquinolinato) manganese, tris (8-hydroxyquinolinate)
Aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8-hydroxyquinolinato) gallium, bis (10-hydroxybenzo [h] quinolinato) beryllium, bis (10-hydroxybenzo [h] Quinolinato) zinc, bis (2-methyl-8-hydroxyquinolinato) chlorogallium, bis (2-methyl-8-hydroxyquinolinate) (o-
Cresolate) gallium, bis (2-methyl-8-hydroxyquinolinate) (1-naphtholato) aluminum, bis (2-methyl-8-hydroxyquinolinate)
(2-naphtholate) gallium, bis (2-methyl-8)
-Hydroxyquinolinato) phenolate gallium, bis (o- (2-benzoxazolyl) phenolate) zinc, bis (o- (2-benzothiazolyl) phenolate) zinc, bis (o- (2-benzotriazolyl) ) Phenolate) zinc and the like, but not limited thereto. Further, as the nitrogen-containing five-membered derivative, an oxazole, thiazole, oxadiazole, thiadiazole or triazole derivative is preferable. In particular,
2,5-bis (1-phenyl) -1,3,4-oxazole, dimethyl POPOP, 2,5-bis (1-phenyl) -1,3,4-thiazole, 2,5-bis (1-phenyl) ) -1,3,4-Oxadiazole, 2- (4 '
-Tert-butylphenyl) -5- (4 "-biphenyl) -1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1,3,4-oxadiazole,
1,4-bis [2- (5-phenyloxadiazolyl)]
Benzene, 1,4-bis [2- (5-phenyloxadiazolyl) -4-tert-butylbenzene], 2-
(4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-thiadiazole, 2,5-bis (1-naphthyl) -1,3,4-thiadiazole,
1,4-bis [2- (5-phenylthiadiazolyl)] benzene, 2- (4'-tert-butylphenyl) -5
-(4 "-biphenyl) -1,3,4-triazole,
2,5-bis (1-naphthyl) -1,3,4-triazole, 1,4-bis [2- (5-phenyltriazolyl)] benzene and the like, but not limited to .

In the present organic EL device, in the light emitting layer,
In addition to the compound of the present invention, at least one kind of light emitting material, doping material, hole injecting material and electron injecting material may be contained in the same layer. Further, in order to improve the stability of the organic EL element obtained by the present invention against temperature, humidity, atmosphere, etc., a protective layer is provided on the surface of the element, or the entire element is protected by silicone oil, resin or the like. Is also possible.

As the conductive material used for the anode of the organic EL element, one having a work function larger than 4 eV is suitable, and carbon, aluminum, vanadium, iron, cobalt, nickel, tungsten, silver, gold, platinum. , Palladium and their alloys, metal oxides such as tin oxide and indium oxide used for ITO substrates and NESA substrates,
Furthermore, organic conductive resins such as polythiophene and polypyrrole are used.

The conductive material used for the cathode is 4
Those having a work function smaller than eV are suitable, and magnesium, calcium, tin, lead, titanium, yttrium, lithium, ruthenium, manganese, aluminum and the like and alloys thereof are used, but are not limited thereto. . As an alloy, magnesium / silver,
Typical examples include magnesium / indium and lithium / aluminum, but the present invention is not limited thereto. The alloy ratio is controlled by the temperature of the vapor deposition source, the atmosphere, the degree of vacuum, etc., and is selected as an appropriate ratio. The anode and the cathode may be formed in a layered structure of two or more layers if necessary.

In the organic EL device, it is desirable that at least one of them is sufficiently transparent in the emission wavelength region of the device in order to emit light efficiently. It is also desirable that the substrate is transparent. The transparent electrode is made of the above-mentioned conductive material and is set by a method such as vapor deposition or sputtering so as to ensure a predetermined translucency. The electrode on the light emitting surface preferably has a light transmittance of 10% or more. The substrate has mechanical and thermal strength, and is not limited as long as it has transparency, but, for example, a glass substrate, a polyethylene plate, a polyethylene terephthalate plate, a polyether sulfone plate, Examples include transparent resins such as polypropylene plates.

Each layer of the organic EL device according to the present invention can be formed by any one of dry film forming methods such as vacuum deposition, sputtering, plasma and ion plating, and wet film forming methods such as spin coating, dipping and flow coating. Can be applied. The film thickness is not particularly limited, but it needs to be set to an appropriate film thickness. If the film thickness is too thick, a large applied voltage is required to obtain a constant light output, resulting in poor efficiency. If the film thickness is too thin, pinholes and the like will occur, and even if an electric field is applied, sufficient emission brightness cannot be obtained. The normal film thickness is preferably in the range of 5 nm to 10 μm, more preferably in the range of 10 nm to 0.2 μm.

In the case of the wet film forming method, the material forming each layer is ethanol, chloroform, tetrahydrofuran,
A thin film is formed by dissolving or dispersing in a suitable solvent such as dioxane, and any solvent may be used. Further, in any of the organic thin film layers, an appropriate resin or additive may be used for improving the film forming property and preventing pinholes in the film. Examples of usable resins include insulating resins such as polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyurethane, polysulfone, polymethylmethacrylate, polymethylacrylate and cellulose, and copolymers thereof, poly-N-vinyl. Examples include photoconductive resins such as carbazole and polysilane, and conductive resins such as polythiophene and polypyrrole. Examples of the additives include antioxidants, ultraviolet absorbers, plasticizers and the like.

As described above, by using the compound of the present invention in the light emitting layer of an organic EL device, it was possible to improve the organic EL device characteristics such as luminous efficiency and maximum luminous brightness. In addition, this device is extremely stable against heat and current, and because it can obtain practically usable light emission brightness at a low driving voltage, it can significantly reduce deterioration, which was a major problem until now. I was able to.

The organic EL device of the present invention can be used as a flat panel display such as a wall-mounted TV or a flat light emitting device.
It can be applied to light sources such as copiers and printers, light sources such as liquid crystal displays and instruments, display boards, marker lights, etc., and its industrial value is very large.

The material of the present invention can also be used in the fields of organic EL devices, electrophotographic photoreceptors, photoelectric conversion devices, solar cells, image sensors and the like.

[0079]

The present invention will be described in more detail based on the following examples. Method for synthesizing compound (5) Under a nitrogen stream, 50 ml of dehydrated ethanol, 6.55 g of p-xylyl cyanide, and 8.76 g of 4-N, N-dimethylaminocinnamaldehyde are stirred and dissolved at room temperature.
To this, sodium ethylate consisting of 250 mg of sodium hydroxide and 30 ml of dehydrated ethanol was slowly added dropwise. By stirring at room temperature for 1 hour, an orange product was precipitated. Then, the mixture was diluted with 100 ml of methanol, the precipitated orange solid was filtered by suction, dispersed and washed with 200 ml of ethanol, and 5.2 g of a yellow-orange solid was obtained by column purification using silica gel. The compound (5) was confirmed by molecular weight analysis by FD-MS, analysis by NMR spectrum and the like. The infrared absorption spectrum (KBr tablet method) of this compound is shown in FIG. Method for synthesizing compound (6) Under a nitrogen stream, 50 ml of dehydrated ethanol, 6.55 g of p-xylyl cyanide and 7.45 g of 4-N, N-dimethylaminobenzyl aldehyde are stirred and dissolved at room temperature.
To this, sodium ethylate consisting of 250 mg of sodium hydroxide and 30 ml of dehydrated ethanol was slowly added dropwise. By stirring at room temperature for 1 hour, a yellow product was precipitated. Then, the mixture was diluted with 100 ml of methanol, and the precipitated yellow solid was filtered by suction and dispersed and washed with 200 ml of ethanol. Column purification with silica gel gave 8.1 g of a yellow solid. The compound (6) was confirmed by molecular weight analysis by FD-MS, analysis by NMR spectrum and the like. The infrared absorption spectrum (KBr tablet method) of this compound is shown in FIG. Method for synthesizing compound (10) Under a nitrogen stream, 100 ml of dehydrated ethanol, 4.12 g of 9-formylanthracene and 3.62 g of 4-bromobenzylcyanide are stirred and dissolved at room temperature. To this, sodium ethylate consisting of 250 mg of sodium hydroxide and 30 ml of dehydrated ethanol was slowly added dropwise. By stirring at room temperature for 1 hour, a yellow product was precipitated. Then, the mixture was diluted with 100 ml of methanol, the precipitated yellow solid was filtered off with suction, and dispersed and washed with 200 ml of ethanol to give 2-cyano-2- (4-bromophenyl).
6.4 g of vinyl-9-anthracene was obtained. 3.8 g of the above compound, 1.97 g of p, p-ditolylamine, 1.9 g of potassium carbonate, 50 ml of nitrobenzene, and 0.1 g of cuprous chloride were heated and stirred at 200 ° C. for 10 hours under a nitrogen stream. 2. By column purification using silica gel.
6 g of a yellow-orange solid was obtained. The compound (10) was analyzed by molecular weight analysis by FD-MS, NMR spectrum and the like.
Was confirmed. The infrared absorption spectrum (KBr tablet method) of this compound is shown in FIG. Method for synthesizing compound (12) Under a nitrogen stream, dehydrated ethanol 100 ml, benzaldehyde 2.12 g, 4-bromobenzyl cyanide 3.92.
g is dissolved by stirring at room temperature. To this, sodium ethylate consisting of 250 mg of sodium hydroxide and 30 ml of dehydrated ethanol was slowly added dropwise. By stirring at room temperature for 1 hour, a yellow product was precipitated. Then, the mixture was diluted with 100 ml of methanol, the precipitated yellow solid was filtered off with suction, and dispersed and washed with 200 ml of ethanol to give 2-cyano-2- (4-bromophenyl) vinyl-.
6.0 g of 1-benzene was obtained. 5.68 the above compound
g, p, p-ditolylamine 3.94 g, potassium carbonate 4.1 g, nitrobenzene 50 ml, cuprous chloride 0.1
g was heated and stirred at 200 ° C. for 10 hours under a nitrogen stream. By column purification using silica gel, 4.5 g of a yellow solid was obtained. Molecular weight analysis by FD-MS, NM
It was confirmed to be the compound (12) by analysis of R spectrum and the like. Infrared absorption spectrum of this compound (KB
r tablet method) is shown in FIG.

Examples using the compounds of the present invention are shown below. In this example, the characteristics of an organic EL device having an electrode area of 2 mm × 2 mm were measured.

Example 1 Compound (10) shown in Table 1 and 2,5-bis (1-naphthyl) as a light emitting material was placed on a washed glass plate with an ITO electrode.
-1,3,4-oxadiazole, polycarbonate resin (Teijin Kasei: Panlite K-1300) 1: 2: 1
It was dissolved in tetrahydrofuran at a weight ratio of 0 and a light emitting layer having a film thickness of 100 nm was obtained by a spin coating method. An electrode having a film thickness of 150 nm was formed on it with an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL element.
The light emission characteristics of this element are as follows:
(Cd / m ² ), maximum emission brightness 1000 (cd / m ² ),
Yellow light emission with a luminous efficiency of 0.10 (lm / W) was obtained. Example 2 On a washed glass plate with an ITO electrode, the compound (12) shown in Table 1 and 2,5-bis (1-naphthyl) as a light emitting material were used.
-1,3,4-oxadiazole, polycarbonate resin (Teijin Kasei: Panlite K-1300) 1: 2: 1
It was dissolved in tetrahydrofuran at a weight ratio of 0 and a light emitting layer having a film thickness of 100 nm was obtained by a spin coating method. An electrode having a film thickness of 150 nm was formed on it with an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL element.
The light emission characteristic of this element is that the light emission luminance is 70 at a DC voltage of 5V.
Yellow-orange light emission with (cd / m ² ), maximum emission luminance of 800 (cd / m ² ) and emission efficiency of 0.10 (lm / W) was obtained.

Example 3 N, N '-(3
-Methylphenyl) -N, N'-diphenyl-1,1 '
-Biphenyl-4,4'-diamine (TPD) was vacuum-deposited to obtain a hole injection layer having a film thickness of 20 nm. Then, the compound (3) was vapor-deposited to form a light-emitting layer having a thickness of 40 nm, and then tris (8-hydroxyquinolinato) aluminum complex (Alq3) was vapor-deposited to obtain an electron injection layer having a thickness of 30 nm. An electrode having a film thickness of 100 nm was formed thereon with an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL element. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has a luminance of 90 (cd / m ² ) at a DC voltage of 5 V, a maximum luminance of 3500 (cd / m ² ), and a luminous efficiency of 0.5 (l).
m / W) yellow-orange emission was obtained.

Example 4 On a cleaned glass plate with an ITO electrode, N, N '-(3
-Methylphenyl) -N, N'-diphenyl-1,1 '
-Biphenyl-4,4'-diamine (TPD) was vacuum-deposited to obtain a hole injection layer having a film thickness of 20 nm. Then, the compound (4) was vapor-deposited to form a light-emitting layer having a film thickness of 40 nm, and then tris (8-hydroxyquinolinato) aluminum complex (Alq3) was vapor-deposited to obtain an electron injection layer having a film thickness of 30 nm. An electrode having a film thickness of 100 nm was formed thereon with an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL element. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has an emission luminance of 90 (cd / m ² ) at a DC voltage of 5 V, a maximum emission luminance of 4500 (cd / m ² ), and an emission efficiency of 0.5 (l
m / W) yellow emission was obtained.

Example 5 Compound (18) was applied onto a washed glass plate with an ITO electrode.
Was dissolved in methylene chloride, and a hole injection type light emitting layer having a film thickness of 50 nm was obtained by a spin coating method. Then, bis (2-methyl-8-hydroxyquinolinate) (1-
Naphthrate) gallium complex is vacuum deposited to a film thickness of 40n
An electron injection layer having a thickness of m was formed, and an electrode having a thickness of 100 nm was formed on the electron injection layer with an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL device. The light emitting layer and the electron injection layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has an emission luminance of 110 at a DC voltage of 5V.
(Cd / m ² ), maximum light emission brightness 7200 (cd /
m ² ), and a yellow-orange emission with a luminous efficiency of 0.60 (lm / W) was obtained.

Example 6 Compound (16) was applied onto a washed glass plate with an ITO electrode.
Was dissolved in methylene chloride, and a hole injection type light emitting layer having a film thickness of 50 nm was obtained by a spin coating method. Then, bis (2-methyl-8-hydroxyquinolinate) (1-
Naphthrate) gallium complex is vacuum deposited to a film thickness of 40n
An electron injection layer having a thickness of m was formed, and an electrode having a thickness of 100 nm was formed on the electron injection layer with an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL device. The light emitting layer and the electron injection layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has a luminance of 100 at a DC voltage of 5V.
(Cd / m ² ), maximum emission brightness 4200 (cd /
m ² ), and an orange light emission with a luminous efficiency of 0.50 (lm / W) was obtained.

Example 7 Compound (6) was vacuum-deposited on a washed glass plate with an ITO electrode to obtain a hole injection type light emitting layer having a film thickness of 50 nm.
Then, a bis (2-methyl-8-hydroxyquinolinato) (phenolate) gallium complex was vacuum-deposited to form an electron injection layer having a film thickness of 30 nm, and magnesium and silver were mixed thereon at a ratio of 10: 1. An electrode having a thickness of 100 nm was formed from the alloy to obtain an organic EL device. The light emitting layer and the electron injection layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has an emission luminance of 80 (cd / m ² ) at a DC voltage of 5 V and a maximum emission luminance of 8100 (cd / m ² ).
m ² ), and an orange emission having a luminous efficiency of 0.6 (lm / W) was obtained.

Example 8 Compound (22) was applied onto a washed glass plate with an ITO electrode.
Was vacuum-deposited to obtain a hole injection type light emitting layer having a film thickness of 50 nm. Then, a bis (2-methyl-8-hydroxyquinolinato) (phenolate) gallium complex was vacuum-deposited to form an electron injection layer having a film thickness of 30 nm, and magnesium and silver were mixed thereon at a ratio of 10: 1. Alloy film thickness 100 nm
An electrode was formed to obtain an organic EL device. The light emitting layer and the electron injection layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has an emission luminance of 130 (cd / m ² ) at a DC voltage of 5 V and a maximum emission luminance of 5200 (c
An orange light emission of d / m ² ) and a luminous efficiency of 0.5 (lm / W) was obtained.

Examples 9 to 18, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD) was vacuum-deposited on a washed glass plate with an ITO electrode to form a film. A hole injection layer having a thickness of 30 nm was formed. Next, the compounds of Table 1 were vacuum-deposited as a light emitting material to obtain a light emitting layer having a film thickness of 30 nm. Then bis (2-methyl-8-hydroxyquinolinate)
(Phenolate) gallium complex is vacuum-deposited to a film thickness of 30.
An electron injection layer having a thickness of 10 nm was formed, and an electrode having a thickness of 100 nm was formed from an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to form an organic EL element. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. Table 2 shows the emission characteristics of this device. The emission brightness here is the brightness when a DC voltage of 5 V is applied. The organic EL devices of this example all have a maximum brightness of 10,000 (cd /
m ² ) or higher, and a luminescence color from yellow to red could be obtained.

[0089]

[Table 2]

Example 19 4,4 ', 4 "was placed on a washed glass plate with ITO electrodes.
-Tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine was vacuum deposited to give a film thickness of 40
A hole injection layer of nm was obtained. Then, α-NPD was vacuum-deposited to obtain a second hole injection layer having a film thickness of 10 nm. Furthermore, the compound (30) is vacuum-deposited to form a light-emitting layer having a film thickness of 30 nm, and a bis (2-methyl-8-hydroxyquinolinato) (1-phenolate) gallium complex is further vacuum-deposited to have a film thickness. An electron injection layer having a thickness of 30 nm was formed, and an electrode having a film thickness of 150 nm was formed on the alloy in which aluminum and lithium were mixed at a ratio of 25: 1 to obtain an organic EL device. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This element is
Luminance 110 (cd / m ² ) at a DC voltage of 5 V, maximum luminance 5500 (cd / m ² ), luminous efficiency 0.5 (l
m / W) yellow-orange emission was obtained.

Example 20 4,4 ', 4 "was placed on a washed glass plate with ITO electrodes.
-Tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine was vacuum deposited to give a film thickness of 40
A hole injection layer of nm was obtained. Then, α-NPD was vacuum-deposited to obtain a second hole injection layer having a film thickness of 10 nm. Furthermore, the compound (16) was vacuum-deposited to form a light-emitting layer having a thickness of 30 nm, and bis (2-methyl-8-hydroxyquinolinato) (1-phenolate) gallium complex was further vacuum-deposited to have a film thickness. An electron injection layer having a thickness of 30 nm was formed, and an electrode having a film thickness of 150 nm was formed on the alloy in which aluminum and lithium were mixed at a ratio of 25: 1 to obtain an organic EL device. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This element is
Luminous intensity of 150 (cd / m ² ) at a DC voltage of 5 V, maximum luminous intensity of 6000 (cd / m ² ), luminous efficiency of 0.6 (l
m / W) yellow-orange emission was obtained.

Example 21 Example 3 was repeated except that a hole injection layer of copper phthalocyanine having a thickness of 5 nm was provided between the ITO electrode and the compound (34).
An organic EL device was produced by the same method as described above. This element is
Luminance of 180 (cd / m ² ) at a DC voltage of 5 V, maximum luminance of 7000 (cd / m ² ), luminous efficiency of 0.6 (lm)
/ W) was obtained.

Example 22 Example 3 was repeated except that a hole injection layer of copper phthalocyanine having a thickness of 5 nm was provided between the ITO electrode and the compound (31).
An organic EL device was produced by the same method as described above. This element is
Luminous intensity 180 (cd / m ² ), maximum luminous intensity 6500 (cd / m ² ) at a DC voltage of 5 V, luminous efficiency 0.6 (lm)
/ W) was obtained.

Example 23 4,4 ', 4 "-tris [N- (3-methylphenyl)]
An organic EL device was produced in the same manner as in Example 15 except that a hole injection layer having a film thickness of 20 nm of metal-free phthalocyanine was provided instead of —N-phenylamino] triphenylamine. This element has an emission luminance of 15 at a DC voltage of 5V.
0 (cd / m ² ), maximum emission brightness 8500 (cd / m ²
m ² ), and an orange emission having a luminous efficiency of 0.9 (lm / W) was obtained.

Example 24 4,4 ', 4 "-tris [N- (3-methylphenyl)
An organic EL device was produced in the same manner as in Example 15 except that a hole injection layer having a film thickness of 20 nm of metal-free phthalocyanine was provided instead of —N-phenylamino] triphenylamine. This element has an emission luminance of 15 at a DC voltage of 5V.
0 (cd / m ² ), maximum emission brightness 7500 (cd / m ²
m ² ), and an orange emission having a luminous efficiency of 0.8 (lm / W) was obtained.

Example 25 Compound (16): α-NPD was used as a light emitting layer in a ratio of 1:10.
An organic EL device was produced in the same manner as in Example 5 except that a thin film having a film thickness of 30 nm vapor-deposited at a ratio of 0 was provided.
This device has a luminance of 180 (cd / cd) at a DC voltage of 5V.
m ² ) Orange emission having a maximum emission luminance of 9500 (cd / m ² ) and an emission efficiency of 0.9 (lm / W) was obtained. Example 26 1:10 of compound (17): α-NPD was used as a light emitting layer.
An organic EL device was produced in the same manner as in Example 5 except that a thin film having a film thickness of 30 nm vapor-deposited at a ratio of 0 was provided.
This device has an emission luminance of 220 (cd / cd at a DC voltage of 5 V).
m ² ) Orange emission having a maximum emission luminance of 8500 (cd / m ² ) and a luminous efficiency of 1.0 (lm / W) was obtained.

Example 27 Compound (2): bis (2-methyl-8-) was used as a light emitting layer.
An organic EL device was produced in the same manner as in Example 5 except that a thin film having a thickness of 30 nm was formed by vapor-depositing a hydroxyquinolinate) (phenolate) gallium complex at a ratio of 1: 100. This device has an emission luminance of 23 at a DC voltage of 5V.
0 (cd / m ² ), maximum emission brightness 23000 (cd / m ^2
2 ), yellow-orange emission with a luminous efficiency of 2.1 (lm / W) was obtained.

Example 28 Compound (6): bis (2-methyl-8-) was used as a light emitting layer.
An organic EL device was produced in the same manner as in Example 5 except that a thin film having a thickness of 30 nm was formed by vapor-depositing a hydroxyquinolinate) (phenolate) gallium complex at a ratio of 1: 100. This device has an emission brightness of 25 at a DC voltage of 5V.
0 (cd / m ² ), maximum emission brightness 25000 (cd / m
² ), yellow-orange emission with a luminous efficiency of 2.8 (lm / W) was obtained.

Example 29 Example 5 was repeated except that a thin film having a thickness of 30 nm was formed by vapor-depositing the compound (7): tris (8-hydroxyquinolinato) aluminum complex at a ratio of 1: 100 as the light emitting layer. An organic EL device was produced by the same method. This device has a luminance of 250 (cd / m ² ) at a DC voltage of 5 V, a maximum luminance of 27500 (cd / m ² ), and a luminous efficiency of 2.3.
Yellow-orange emission of (lm / W) was obtained.

Example 30 The same as Example 5 except that a thin film having a thickness of 30 nm was formed by vapor-depositing the compound (12): tris (8-hydroxyquinolinato) aluminum complex at a ratio of 1: 100 as the light emitting layer. An organic EL device was produced by the same method. This device has a light emission brightness of 350 (cd / m ² ), a maximum light emission brightness of 35000 (cd / m ² ), and a light emission efficiency of 3.3 at a DC voltage of 5V.
Yellow luminescence of (lm / W) was obtained.

Example 31 Compound (14): Compound (20) was added to the light emitting layer in the amount of 5
An organic EL device was produced in the same manner as in Example 5, except that a thin film having a film thickness of 30 nm vapor-deposited at a ratio of 0:50 was provided. This device has an emission luminance of 250 (c
d / m ² ) Maximum emission A yellow-orange emission with a luminance of 8500 (cd / m ² ) and a luminous efficiency of 0.9 (lm / W) was obtained.

Example 32 Compound (13): Compound (20) was used as a light emitting layer in an amount of 5
An organic EL device was produced in the same manner as in Example 5, except that a thin film having a film thickness of 30 nm vapor-deposited at a ratio of 0:50 was provided. This device has an emission luminance of 250 (c
d / m ² ) Maximum light emission: An orange light emission with a luminance of 11,000 (cd / m ² ) and a light emission efficiency of 0.9 (lm / W) was obtained.

Example 33 As a light emitting layer, α-NPD: compound (22) was added to 100:
An organic EL device was produced in the same manner as in Example 15 except that a thin film having a film thickness of 30 nm vapor-deposited at a ratio of 5 was provided. This device has an emission luminance of 270 (c
d / m ²⁾ maximum radiance 15500 (cd / m ^2), orange light emission efficiency 1.5 (lm / W) was obtained.

Example 34 As a light emitting layer, α-NPD: compound (21) was added to 100:
An organic EL device was produced in the same manner as in Example 15 except that a thin film having a film thickness of 30 nm vapor-deposited at a ratio of 5 was provided. This device has an emission luminance of 280 (c
d / m ²⁾ maximum radiance 18500 (cd / m ^2), yellow-orange light emission efficiency 1.7 (lm / W) was obtained.

Example 35 As the light emitting layer, compound (14): 4- (dicyanomethyl
) -2-Methyl-6- (p-dimethylaminostyrene)
Steam) 4H-pyran (DCM) at a ratio of 50:50.
A thin film with a thickness of 30 nm is provided, and tris (8-
Vacuum deposition of (hydroxyquinolinate) aluminum complex
Except that the electron injection layer with a thickness of 30 nm is formed
An organic EL device was produced in the same manner as in Example 15. This element
The child has an emission luminance of 500 (cd / m at a DC voltage of 5 V).²)
Maximum emission brightness 15000 (cd / m ²), Luminous efficiency 1.
A yellow-orange emission of 4 (lm / W) was obtained.

Comparative Example 1 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD) was vacuum-deposited on a washed glass plate with an ITO electrode to form a film having a thickness of 30 nm. The hole injection layer of was formed. Then, the following compound (49) was vacuum-deposited as a light emitting material to obtain a light emitting layer having a film thickness of 30 nm.
Then, a bis (2-methyl-8-hydroxyquinolinato) (phenolate) gallium complex was vacuum-deposited to form an electron injection layer having a film thickness of 30 nm, and magnesium and silver were mixed thereon at a ratio of 10: 1. An electrode having a thickness of 100 nm was formed from the alloy to obtain an organic EL device. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has an emission brightness of 60 (cd / m ² ) at a DC voltage of 5 V and a maximum emission brightness of 6500 (cd / m ² ).
m ² ), and blue-green light emission with a luminous efficiency of 0.4 (lm / W) was obtained. Compound [49]

[0107]

[Chemical 6]

Comparative Example 2 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD) was vacuum-deposited on a washed glass plate with an ITO electrode to form a film having a thickness of 30 nm. The hole injection layer of was formed. Then, the following compound (50) was vacuum-deposited as a light emitting material to obtain a light emitting layer having a film thickness of 30 nm.
Then, a bis (2-methyl-8-hydroxyquinolinato) (phenolate) gallium complex was vacuum-deposited to form an electron injection layer having a film thickness of 30 nm, and magnesium and silver were mixed thereon at a ratio of 10: 1. An electrode having a thickness of 100 nm was formed from the alloy to obtain an organic EL device. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. This device has an emission luminance of 60 (cd / m ² ) at a DC voltage of 5 V and a maximum emission luminance of 1500 (cd / m ² ).
m ² ), green light emission with a light emission efficiency of 0.1 (lm / W) was obtained, but spots were observed on the light emitting surface, and the light emission life was several hours. Compound [50]

[0109]

[Chemical 7]

As is clear from the comparison between Comparative Example 1 and Comparative Example 2 and Example 8, the presence of a cyano group in R ⁵ causes the emission color to change to yellow-red and the characteristics such as maximum emission luminance are remarkable. Improvement was seen.

The organic EL device shown in this example has a maximum emission luminance of 10,000 in the device structure of two layers or more.
Light emission of (cd / m ² ) or more was obtained, and high emission efficiency could be obtained in all cases. When the organic EL device shown in this example was made to continuously emit light at 3 (mA / cm ² ), stable light emission for 1000 hours or more could be observed.

The organic EL device of the present invention achieves improvement of luminous efficiency, luminous brightness and prolongation of life, and is used together with a light emitting material, a doping material, a hole injecting material, an electron injecting material and a sensitizing material. It does not limit the agent, resin, electrode material, etc., and the method for producing the element.

The organic EL device shown in this embodiment has a maximum emission luminance of 5000 (c
Light emission of not less than d / m ² ) was obtained, and high emission efficiency could be obtained in all cases. When the organic EL device shown in this example was made to continuously emit light at 2 (mA / cm ² ),
Stable light emission could be observed for 1000 hours or more.

The organic EL device of the present invention achieves improvement in luminous efficiency, luminous brightness and long life, and is used together with a light emitting material, a doping material, a hole injecting material, an electron injecting material and a sensitizing material. It does not limit the agent, resin, electrode material, etc., and the method for producing the element.

[0115]

The organic EL device using the organic EL device material of the present invention as a light emitting material has a cyano group in the double bond of the styryl skeleton, and thus can emit light in the long wavelength range from yellow to red. In addition, it is possible to obtain an organic EL element having higher luminous efficiency and higher luminance than conventional ones and having a long luminous lifetime.

[Brief description of drawings]

1] Infrared absorption spectrum of compound (5)

FIG. 2 is an infrared absorption spectrum diagram of compound (6).

FIG. 3 is an infrared absorption spectrum diagram of compound (10).

FIG. 4 is an infrared absorption spectrum diagram of compound (12).

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C07D 333/60 C07D 333/60 4C204 471/04 112 471/04 112Z 4H006 H05B 33/14 H05B 33/14 B // C07D 209/86 C07D 209/86 333/24 333/24 F term (reference) 3K007 AB02 AB03 AB04 AB06 AB11 CA01 CB01 DA01 DB03 EB00 4C023 EA11 4C037 HA31 4C056 AA02 AB01 AC03 AD05 AE01 EA01 EB01 EC0 CC09A03A0 DD01 EE02 HH01 HH02 JJ01 KK01 KK02 LL01 PP03 4C204 BB05 BB09 CB25 DB01 EB01 FB03 FB08 FB25 GB19 4H006 AA03 AB90 QN30

Claims (6)

[Claims] 1. A material for an organic electroluminescence device represented by the following general formula [1]. General formula [1] [In the formula, Ar ¹ represents a monovalent organic residue containing a monocycle or a condensed polycycle, Ar ² represents a divalent organic residue containing a monocycle or a condensed polycycle, and R ^{1 to} R ^{1 8} independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group,
At least one of R ^{5 and} R ⁶ is a cyano group. R ¹
Alternatively, a ring may be formed between R ² and Ar ² . n, m
Is an integer from 0 to 10. ] 2. In an organic electroluminescence device comprising a light emitting layer or a plurality of organic compound thin films including a light emitting layer formed between a pair of electrodes, any one of the layers is
An organic electroluminescence device comprising the material for organic electroluminescence device according to claim 1 alone or as a mixture. 3. An organic electroluminescence device comprising a light emitting layer or a plurality of organic compound thin films including a light emitting layer formed between a pair of electrodes, wherein the light emitting layer is the material for an organic electroluminescence device according to claim 1. Alternatively, the organic electroluminescence device is contained as a mixture. 4. The organic electroluminescence device according to claim 2, further comprising a hole injection layer formed between the anode and the light emitting layer. 5. The organic electroluminescence device according to claim 2, further comprising an electron injection layer formed between the cathode and the light emitting layer. 6. The organic electroluminescence device according to claim 5, wherein the electron injection layer is a layer containing a metal complex compound or a nitrogen-containing aromatic ring compound.