JPH09268284A - Luminescent material for organic electroluminescence element and organic electroluminescent element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a luminescent material for organic electroluminescent element which has a specific chemical structure, can attain high intensity and luminescent properties of high efficiency, shows excellent durability in stability, when used repetitively, and is useful in a high-intensity luminescent element to be used in a planar light source or a display. SOLUTION: This luminescent material has a chemical structure represented by formula I A and X<1> -X<4> are each a (substituted) 6-20C arylene; Y<1> -Y<4> are each a group of formula II [R<1> -R<4> are each H, (substituted) alkyl, (substituted) aryl, cyano; R<1> and R<2> or R<3> and R<4> may bond to each other to form a triple bond; Z is a (substituted) aryl; n is 0, 1]; a-d are each 0-2} and typically N,N,N', N'-tetrakis(4-styrilphenyl)-p-phenylenediamine is exemplified.

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 device using an organic substance is expected to be used as an inexpensive, large-area, full-color display device of a solid light emitting type, and many developments have been made. Generally EL
Is composed of a light-emitting layer and a pair of opposed electrodes sandwiching the layer. In light emission, when an electric field is applied between both electrodes, electrons are injected from the cathode side and holes are injected from the anode side. Further, the electrons are recombined with holes in the light emitting layer, and energy is emitted as light when the energy level returns from the conduction band to the valence band.

[0003] Conventional organic EL devices have a higher driving voltage and lower luminous brightness and luminous efficiency than inorganic EL devices.
In addition, the characteristic deterioration was remarkable, and it had not been put to practical use.
2. Description of the Related Art In recent years, an organic EL in which a thin film containing an organic compound having high fluorescence quantum efficiency that emits light at a low voltage of 10 V or less is laminated.
Devices have been reported and are of interest (see Applied Physics Letters, vol. 51, p. 913, 1987). This method uses a metal chelate complex for a light emitting layer and an amine compound for a hole injection layer to obtain high-intensity green light emission.
d / m ² and maximum luminous efficiency of 1.5 lm / W,
Has performance close to the practical range.

[0004] However, organic EL devices up to now have improved luminous intensity due to the improved structure, but do not yet have sufficient luminous brightness. In addition, there is a major problem that the stability upon repeated use is poor. 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 a cathode, and is greatly deteriorated by short-time light emission. I was For the above reasons, in order to develop an organic EL device having high luminous luminance and luminous efficiency and excellent stability in repeated use, development of a durable luminescent material having excellent luminous ability has been required. Is desired.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic EL device having a high emission luminance and excellent stability when used repeatedly. As a result of diligent studies by the present inventors, the organic EL device using at least one layer of the organic EL device material represented by the general formula [1] has high emission brightness and emission efficiency, and excellent stability during repeated use. Therefore, the present invention has been accomplished.

[0006]

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

[0007]

Embedded image

[In the formula, A and X ^{1 to} X ⁴ each independently represent a substituted or unsubstituted arylene group having 6 to 20 carbon atoms. Y ^{1 to} Y ⁴ each independently represent an organic group represented by the following general formula [2]. General formula [2]

[0009]

[Chemical 6]

(Wherein R ^{1 to} R ⁴ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a cyano group, or R ¹ and R ² or R ³ and R
⁴ represents a triple bond bonded. Z represents a substituted or unsubstituted aryl group. a to d represent a positive integer of 0 to 2. n represents 0 or 1. )]

Further, the present invention is the above-mentioned material for an organic electroluminescence device, wherein A in the general formula [1] is a substituted or unsubstituted condensed arylene group having 10 to 20 carbon atoms.

Furthermore, the present invention is a light emitting material for an organic electroluminescence device represented by the above general formula [1].

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, at least one of which contains the material for an organic electroluminescence device. It is an organic electroluminescence element which is a layer.

The present invention further provides a layer containing an aromatic tertiary amine derivative and / or a phthalocyanine derivative,
The above organic electroluminescent element is formed between the light emitting layer and the anode.

Further, the present invention is the above organic electroluminescent device, wherein the aromatic tertiary amine derivative is a compound represented by the following general formula [3]. General formula [3]

Embedded image [In the formula, B ^{1 to} B ⁴ each independently represent a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. G
Represents a substituted or unsubstituted arylene group. ]

Further, the present invention is the above organic electroluminescence device, wherein a layer containing a metal complex compound or a nitrogen-containing five-membered ring derivative is formed between the light emitting layer and the cathode.

Furthermore, the present invention is the above organic electroluminescent device, wherein the metal complex compound is a compound represented by the following general formula [4]. General formula [4]

Embedded image [Wherein Q ¹ and Q ² each independently represent a substituted or unsubstituted hydroxyquinoline derivative or a substituted or unsubstituted hydroxybenzoquinoline derivative;
Is a halogen atom, a substituted or unsubstituted alkyl group,
A substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group optionally containing a nitrogen atom, -OR
(R is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, or a substituted or unsubstituted aryl group which may contain a nitrogen atom.),
Represents a ligand represented by —O—Ga—Q ³ (Q ⁴ ) (Q ³ and Q ⁴ have the same meaning as Q ¹ and Q ² ). ]

BEST MODE FOR CARRYING OUT THE INVENTION

A and X ^{1 to} X ⁴ of the compound represented by the general formula [1] in the present invention each independently represent a substituted or unsubstituted arylene group having 6 to 20 carbon atoms. Specific examples of A and X ^{1 to} X ⁴ are phenylene group, biphenylene group, terphenylene group, naphthylene group, anthrylene group, phenanthrylene group, fluorenylene group,
It is an arylene group such as a pyrenylene group or a thiophenylene group, and an arylene group represented by the following general formula [5] or general formula [6], but is not limited thereto.
The condensed arylene group having 10 to 20 carbon atoms has 10 carbon atoms such as naphthylene group, anthrylene group, phenanthrylene group, fluorenylene group, and pyrenylene group.
Represents a divalent fused aromatic ring consisting of

General formula [5]

Embedded image

General formula [6]

Embedded image

Here, general formula [5] and general formula [6]
Ar ^{1 to} Ar ⁴ each independently represent a substituted or unsubstituted arylene group having 6 to 20 carbon atoms. Ar ¹
Specific examples of Ar ⁴ to Ar ⁴ include a phenylene group, a biphenylene group,
Terphenylene group, naphthylene group, anthrylene group, phenanthrylene group, fluorenylene group, pyrenylene group,
An arylene group such as a thiophenylene group. D ^{1 to} D ³
Is a direct bond or a divalent linking group consisting of a chemically rational combination composed of 1 to 50 atoms selected from C, N, H, O and S.

R ^{1 to} R ⁴ of the compound represented by the general formula [2] in the present invention each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a cyano group. . Specific examples of R ^{1 to} R ⁴ include 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, and a heptyl group as the substituted or unsubstituted alkyl group. , 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, 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 biphenyl group, a 4-methylbiphenyl group and a 4-ethylbiphenyl group. Group, 4-cyclohexylbiphenyl group, terphenyl group, 3,5-dichlorophenyl group, naphthyl group, 5-
There are methylnaphthyl group, anthryl group, pyrenyl group and the like. In the general formula [1], a to d are each independently 0.
Represents a positive integer of 2 and n independently represents 0 or 1.

Z in the compound represented by the general formula [2] in the present invention each independently represents a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Specific examples of Z are aryl groups such as phenyl group, biphenyl group, terphenyl group, naphthyl group, anthryl group, phenanthryl group, fluorenyl group, pyrenyl group and thiophene group,
The aryl group may have a substituent. Specific examples of the substituent include, in addition to the alkyl group and aryl group described for R ^{1 to} R ⁴ , an alkoxy group, an amino group, a cyano group,
There are hydroxyl group, carboxylic acid group, ether group, ester group and the like.

Representative examples of the compound of the general formula [1] of the present invention are specifically shown in Table 1 below, but the present invention is not limited to these representative examples.

[0025]

[Table 1]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

Specific examples of B ^{1 to} B ⁴ of the compound represented by the general formula [3] in the present invention are substituted or unsubstituted aryl groups having 6 to 20 carbon atoms. Specifically, it is an aryl group that may contain a nitrogen atom, such as a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a fluorenyl group, and a pyrenyl group, and each aryl group is substituted. It may have a group. G is a divalent arylene group, which may contain a nitrogen atom such as a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group, an anthrylene group, a phenanthrylene group, a fluorenylene group, and a pyrenylene group. And each aryl group may have a substituent.

Representative examples of the compound of the general formula [3] of the present invention which is an effective hole injecting material and other materials are specifically shown in Table 2 below, which is a representative example of the present invention. It is not limited to the example.

[0039]

[Table 2]

[0040]

[0041]

[0042]

The compound represented by the general formula [4] in the present invention
Q of compound¹, Q^FourIs 8-hydroxyquinoline, 8-hi
Droxyquinaldine, 8-hydroxy-2-phenyl key
Norrin, 8-hydroxy-5-methylquinoline, 8-hi
Hydrides such as droxy-3,5,7-trifluoroquinoline
Roxyquinoline derivative, L is a halogen atom,
Or unsubstituted alkyl group, substituted or unsubstituted cyclo
Even if it contains an alkyl group or a substituted or unsubstituted nitrogen atom
Good aryl group, -OR (R is hydrogen atom, substituted or
Unsubstituted alkyl group, substituted or unsubstituted cycloal
It may contain a kill group or a substituted or unsubstituted nitrogen atom.
It is an aryl group. ), -O-Ga-Q ^Three(Q^Four) (Q
^ThreeAnd Q^FourIs Q¹And Q^TwoHas the same meaning as )
Is shown. Here, a halogen atom, an alkyl group, a cycloalkyl group
A alkyl group, an aryl group which may contain a nitrogen atom, and
-OR group R alkyl group, cycloalkyl group, nitrogen atom
The aryl group which may contain a child is represented by the above general formula [2].
Described R¹~ R^FourRepresents the same group as

The representative examples of the compound of the general formula [4] and the representative examples of the electron injection material used in the organic EL device of the present invention are specifically shown in Table 3 below. It is not limited to the example.

[0045]

[Table 3]

[0046]

[0047]

[0048]

[0049]

[0050]

The compound represented by the general formula [1] 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 hole injecting property and hole transporting property from the metal electrode or the organic thin film layer, and excellent electron injecting property and electron transporting property from the metal electrode or the organic thin film layer, it can be used as a light emitting material. It can be effectively used, and further, another hole transporting material, electron transporting material or doping material may be 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-injection material or an electron-injection material for transporting holes injected from an anode or electrons injected from a cathode to the light-emitting material. However, the luminescent material of the present invention
Since it has extremely high emission quantum efficiency, high hole transport ability and electron transport ability and can form a uniform thin film, it is possible to form a light emitting layer using only the light emitting material of the present invention. The multilayer type includes (anode / hole injection layer / electron injection layer / cathode), (anode / hole injection layer / electron injection layer / cathode), and (anode / hole injection layer / light emission layer / electron injection layer / cathode) multilayer. There is an organic EL element stacked in a configuration. The compound of the general formula [1] has a high light emitting property and has a hole injecting property, a hole transporting property, an electron injecting property, and an electron transporting property, so that 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 general formula [1] of the present invention, a further known light emitting material,
A doping material, a hole injection material, or an electron injection material can also be used. When the organic EL element has a multilayer structure, it is possible to prevent a decrease in luminance and life due to quenching. If necessary, a combination of a light emitting material, a doping material, a hole injection material, and an electron injection material can be used. Further, by using the doping material, it is possible to improve emission brightness and emission efficiency and obtain red and blue emission. Further, each of the hole injection layer, the light emitting layer, and the electron injection layer may be formed in a layer structure of two or more layers. In this case, in the case of a hole injection layer, a layer for injecting holes from the electrode is a hole injection layer, and a layer for receiving holes from the hole injection layer and transporting holes to the light emitting layer is a hole transport layer. Call. Similarly, in the case of an electron injection layer, a layer for injecting electrons from the electrode is an electron injection layer,
A 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 depending on 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 general formula [1], anthracene, naphthalene, phenanthrene, pyrene, tetracene, coronene, chrysene, fluorescein, perylene, phthaloperylene, naphthaloperylene, perinone, phthaloperinone, Naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, 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, quinacry Emissions, there are rubrene and fluorescent dyes, etc., but is not limited thereto.

The hole-injecting material has the ability to transport holes, has the effect of injecting holes from the anode, and has an excellent effect of injecting holes into the light-emitting layer or the light-emitting material. Examples thereof include compounds that prevent excitons from moving to the electron injection layer or the electron injection material and have excellent thin film forming ability. Specifically, phthalocyanine derivatives, naphthalocyanine derivatives, porphyrin derivatives, 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 derivatives thereof, and polyvinyl carbazole , Polysilane, and a polymer material such as a conductive polymer, but are not limited thereto.

Among the hole injecting materials that can be used in the organic EL device of the present invention, the more effective hole injecting material is
The aromatic tertiary amine derivative or phthalocyanine derivative represented by the general formula [3]. Specifically, triphenylamine, tritolylamine, tolyldiphenylamine, N, N′-diphenyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N, N ', N'-(4-methylphenyl)-
1,1'-phenyl-4,4'-diamine, N, N,
N ', N'-(4-methylphenyl) -1,1'-biphenyl-4,4'-diamine, N, N'-diphenyl-
N, N'-dinaphthyl-1,1'-biphenyl-4,
4'-diamine, N, N '-(methylphenyl) -N,
N '-(4-n-butylphenyl) -phenanthrene-
There are 9,10-diamine, N, N-bis (4-di-4-tolylaminophenyl) -4-phenyl-cyclohexane, etc., or oligomers or polymers having these aromatic tertiary amine skeletons. It is not limited to these.

As the phthalocyanine (Pc) derivative,
H ₂ Pc, CuPc, CoPc, NiPc, ZnPc,
PdPc, FePc, MnPc, ClAlPc, ClG
aPc, ClInPc, ClSnPc, Cl ₂ SiP
c, (HO) AlPc, (HO) GaPc, VOPc,
Examples include, but are not limited to, phthalocyanine derivatives such as TiOPc, MoOPc, GaPc-O-GaPc, and naphthalocyanine derivatives.

The electron injecting material has an ability to transport electrons, has an effect of injecting holes from the cathode and an excellent electron injecting effect on the light emitting layer or the light emitting material, and excites generated in the light emitting layer. Examples thereof include compounds that prevent migration to the hole injection layer and have excellent thin film forming ability. For example, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidenemethane, anthraquinodimethane,
Examples include, but are not limited to, anthrones and derivatives thereof. In addition, sensitization can be performed by adding an electron accepting substance to the hole injecting material and adding an electron donating substance to the electron injecting material.

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, as the metal complex compound, lithium 8-hydroxyquinolinate, bis (8
-Hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, tris (8-hydroxyquinolinato)
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-quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) (o-cresolate) gallium, bis (2-methyl-8-quinolinato) (1-naphtholate) aluminum , Bis (2-methyl-8-quinolinato) (2-naphtholate) gallium and the like,
It is not limited to these. As the nitrogen-containing five-membered derivative, an oxazole, thiazole, oxadiazole, thiadiazole or triazole derivative is preferable. Specifically, 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 are not limited thereto.

In the present organic EL device, in the light emitting layer,
In addition to the compound of the general formula [1], at least one of a light emitting material, a doping material, a hole injection material and an electron injection material may be contained in the same layer. Further, in order to improve the stability of the organic EL device obtained by the present invention against temperature, humidity, atmosphere, etc., a protective layer may be provided on the surface of the device,
It is also possible to protect the entire element with silicone oil, resin or the like.

As the conductive material used for the anode of the organic EL device, 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,
Further, an organic conductive resin such as polythiophene or polypyrrole is used. As the conductive material used for the cathode, those having a work function smaller than 4 eV are suitable, and magnesium, calcium, tin, lead, titanium,
Yttrium, lithium, ruthenium, manganese, aluminum and the like and alloys thereof are used, but not limited thereto. Representative examples of the alloy include magnesium / silver, magnesium / indium, and lithium / aluminum, but are not limited thereto. The ratio of the alloy is controlled by the temperature, atmosphere, degree of vacuum, and the like of the evaporation source, and is selected to be an appropriate ratio. The anode and the cathode may be formed by 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. Further, it is desirable that the substrate is also transparent. The transparent electrode is set using the above-described conductive material so as to secure a predetermined translucency by a method such as vapor deposition or sputtering. The electrode on the light emitting surface desirably has a light transmittance of 10% or more. The substrate is not limited as long as it has mechanical and thermal strength and is transparent, but includes a glass substrate and a transparent resin film. As the transparent resin film, polyethylene,
Ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polypropylene, polystyrene, polymethylmethacrylate, polyvinyl chloride, polyvinyl alcohol, polyvinyl butyral, nylon, polyether ether ketone, polysulfone, polyether sulfone, tetra Fluoroethylene-perfluoroalkyl vinyl ether, polyvinyl fluoride, tetrafluoroethylene-ethylene, tetrafluoroethylene-hexafluoropropylene, polychlorotrifluoroethylene, polyvinylidene fluoride, polyester, polycarbonate, polyurethane, polyimide, polyetherimide, polyimide , Polypropylene and the like.

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 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 small, pinholes and the like are generated, and sufficient light emission luminance cannot be obtained even when an electric field is applied. The normal film thickness is suitably in the range of 5 nm to 10 μm, but is 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,
The thin film is formed by dissolving or dispersing in a suitable solvent such as dioxane, and any solvent may be used. In any of the organic thin film layers, a suitable resin or additive may be used for improving film forming properties, preventing pinholes in the film, and the like. Examples of usable resins include insulating resins such as polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyurethane, polysulfone, polymethyl methacrylate, polymethyl acrylate, and cellulose, and copolymers thereof, and poly-N-vinyl. Examples thereof include photoconductive resins such as carbazole and polysilane, and conductive resins such as polythiophene and polypyrrole. Examples of the additive include an antioxidant, an ultraviolet absorber, and a plasticizer.

As described above, by using the compound of the present invention in the light emitting layer of an organic EL element and further combining it with a specific hole injecting layer or electron injecting layer, the organic EL element having the luminous efficiency, the maximum light emission luminance and the like can be obtained. The characteristics could be improved. In addition, this device is extremely stable against heat and current, and furthermore, it can emit light that can be practically used at a low driving voltage, so that the deterioration, which has been a major problem until now, can be significantly reduced. Was completed.

The organic EL device of the present invention can be used as a flat panel display such as a wall-mounted television or a flat light-emitting body.
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.

[0068]

The present invention will be described in more detail with reference to the following examples. Example 1 On a washed glass plate with an ITO electrode, the compound (3) in Table 1 as a light emitting material, 2,5-bis (1-naphthyl)-
1,3,4-oxadiazole and a polycarbonate resin (Teijin Kasei: Panlite K-1300) were dissolved in tetrahydrofuran at a weight ratio of 5: 3: 2, and a 100 nm-thick light emitting layer was obtained by spin coating. . An electrode having a thickness of 150 nm was formed thereon with an alloy of magnesium and silver mixed at a ratio of 10: 1 to obtain an organic EL device. The emission characteristics of this element are 130 (cd /
m ² ), maximum brightness of 3200 (cd / m ²⁾ , luminous efficiency of 0.
A light emission of 95 (lm / W) was obtained.

Example 2 On a cleaned glass plate with ITO electrodes, the compounds of Table 1
(8) is vacuum-deposited to form a light emitting layer with a thickness of 100 nm.
Then, magnesium and silver were mixed at a ratio of 10: 1.
An electrode with a thickness of 100 nm is formed of an alloy to produce an organic EL device.
Obtained. The light emitting layer is 10 ^-6Substrate temperature chamber in Torr vacuum
It was deposited under warm conditions. This device has a DC voltage of 5V
10 (cd / m^Two), Maximum brightness 2200 (cd /
m^Two), Light emission with a luminous efficiency of 0.75 (lm / W) was obtained.
Was.

Example 3 Compound (12) shown in Table 1 was dissolved in methylene chloride on a washed glass plate with an ITO electrode, and a light emitting layer having a thickness of 50 nm was obtained by spin coating. Then, Table 3
Of the compound (B-10) is vacuum-deposited to form an electron-injection layer having a thickness of 30 nm, and magnesium and silver (1) are added to the layer.
An electrode having a thickness of 100 nm was formed from an alloy mixed with 0: 1 to obtain an organic EL element. 10 for the light emitting layer and the electron injection layer
Deposition was carried out in a vacuum of ^-6 Torr at a substrate temperature of room temperature. This element is 350 (cd /
m ² ), maximum brightness of 5400 (cd / m ² ), and luminous efficiency of 1.3 (lm / W) were obtained.

Example 4 The compound (16) shown in Table 1 was vacuum-deposited on a washed glass plate with an ITO electrode to form a light emitting layer with a film thickness of 50 nm. Then, the compound (B-3) in Table 3 is vacuum-deposited to form an electron injection layer having a film thickness of 10 nm, and an alloy in which magnesium and silver are mixed at a ratio of 10: 1 has a film thickness of 100 nm.
Was formed to obtain an organic EL device. The hole injection layer and the light emitting layer were deposited in a vacuum of 10 ^-6 Torr at a substrate temperature of room temperature. This device has a DC voltage of 5V
0 (cd / m ² ), maximum brightness 10000 (cd / m ²
m ² ), and green light emission with a luminous efficiency of 1.6 (lm / W) was obtained.

Examples 5 to 51 On a cleaned glass plate with an ITO electrode, under the conditions shown in Table 4,
The hole injection material was vacuum-deposited to obtain a hole injection layer having a thickness of 30 nm. Next, a luminescent material is vacuum-deposited to a thickness of 30 n.
m light emitting layers were obtained. Further, an electron injecting material is vacuum-deposited to form an electron injecting layer having a thickness of 30 nm.
An electrode having a thickness of m was formed to obtain an organic EL device. Each layer was deposited at a substrate temperature of room temperature in a vacuum of 10 ^-6 Torr. Table 4 shows the emission characteristics of this device. The emission luminance here is the luminance when a DC voltage of 5 V is applied, and all the organic EL elements of this embodiment have a maximum luminance of 10,000 (cd / m
² ) It had the above high luminance characteristics. As the element structure of the organic EL element, the element in which the light emitting material of the general formula and the hole injecting material of the general formula [3] and the electron injecting material of the general formula [4] were combined exhibited the best characteristics.

[0073]

[Table 4]

Example 52 A hole injection material (A-13) was vacuum-deposited on a washed glass plate with an ITO electrode to obtain a hole injection layer having a thickness of 40 nm. Next, the compound (8) was vacuum-deposited as a light emitting material to obtain a light emitting layer having a thickness of 40 nm. Furthermore, (B-11) is vacuum-deposited as an electron injection material to obtain a film thickness of 30 n.
m electron injection layer was obtained. An electrode having a film thickness of 150 nm was formed on the aluminum: lithium alloy with a ratio of 50: 1 to obtain an organic EL device. This element has a DC voltage of 5
8000 (cd / m ² ) at V, maximum brightness 131000
Light emission with (cd / m ² ) and a luminous efficiency of 13.8 (lm / W) was obtained.

Example 53 A hole injecting layer having a film thickness of 5 nm of metal-free phthalocyanine was provided between the ITO electrode and the compound (A-13), except that
An organic EL device was produced in the same manner as in Example 52. This element is 10000 (cd / m ² ) at 5V DC voltage,
Maximum brightness 99000 (cd / m ² ), luminous efficiency 10.2
Light emission of (lm / W) was obtained.

Example 54 Example 48 was repeated except that a hole injection layer having a film thickness of 15 nm of metal-free phthalocyanine was provided instead of the compound (A-13).
An organic EL device was produced in the same manner as in the above. This element
3500 (cd / m ² ) at DC voltage 5V, maximum brightness 77
Light emission of 000 (cd / m ² ) and a luminous efficiency of 5.8 (lm / W) was obtained.

Examples 55 to 64 Compound (8) and the compounds shown in Table 5 were used as a light emitting layer in an amount of 1: 1.
An organic EL device was produced in the same manner as in Example 52 except that the light emitting layer having a film thickness of 20 nm vapor-deposited at a weight ratio of 00: 1 was used. Table 6 shows the emission characteristics of this device. The light emission luminance here is the luminance when a DC voltage of 5 V is applied, and all the organic EL elements of this example have a maximum luminance of 10,000 (cd
/ M ² ) or more, and a desired emission color could be obtained.

[0078]

[Table 5]

[0079]

[0080]

[Table 6]

The organic EL device shown in this example has a luminous brightness of 10,000 (cd / m ² ) or more, and all of them can obtain high luminous efficiency. When the organic EL device shown in this example was continuously emitted at 3 (mA / cm ² ), stable emission was observed for 1000 hours or more, and almost no dark spot was observed. The organic EL device using the organic EL device material of the present invention has a very high fluorescence quantum efficiency of the light emitting material, so that in the device using this light emitting material, high brightness light emission in a low current application region is possible, Further, by using a doping material in addition to the compound of the general formula [1] in the light emitting layer, the maximum light emission brightness and the maximum light emission efficiency could be improved. Furthermore, by adding a doping material for red light emission or blue light emission to the compound of the general formula [1] that emits blue-green light, green light and yellow light, a light emitting device emitting red light or blue light could be obtained. .

The organic EL device of the present invention achieves an improvement in luminous efficiency, luminous brightness and a long life, and is used together with a luminescent material, a doping material, a hole injection material, an electron injection material, and a sensitizer. It does not limit the agent, resin, electrode material and the like, and the element manufacturing method.

[0083]

According to the organic EL device using the organic EL device material of the present invention as a light-emitting material, the device emits light with high luminous efficiency and high luminance as compared with the prior art, and a long-life organic EL device can be obtained. . As described above, using the compound shown in the present invention in at least one layer of an organic EL device, and
With the organic EL device formed by the device configuration of the present invention, an organic EL device having high luminance, high luminous efficiency, and long life can be easily manufactured.

Claims (8)

[Claims] 1. A material for an organic electroluminescence device represented by the following general formula [1]. General formula [1] [In the formula, A and X ^{1 to} X ⁴ each independently represent a substituted or unsubstituted arylene group having 6 to 20 carbon atoms. Y ^{1 to} Y ⁴ each independently represent an organic group represented by the following general formula [2]. General formula [2] (In the formula, R ^{1 to} R ⁴ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a cyano group, or R ¹ and R ² or R ³ and R ⁴ are bonded to each other. Represents a triple bond, Z represents a substituted or unsubstituted aryl group, a to d represent a positive integer of 0 to 2, and n represents
Represents 0 or 1. )] 2. The material for an organic electroluminescence device according to claim 1, wherein A in the general formula [1] is a substituted or unsubstituted condensed arylene group having 10 to 20 carbon atoms. 3. The material for an organic electroluminescence device according to claim 1, which is a light emitting material for an organic electroluminescence device. 4. 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, at least one of which is a material for an organic electroluminescence device according to claim 1. An organic electroluminescence element which is a layer containing. 5. The organic electroluminescence device according to claim 4, wherein a layer containing an aromatic tertiary amine derivative and / or a phthalocyanine derivative is formed between the light emitting layer and the anode. 6. The organic electroluminescent device according to claim 5, wherein the aromatic tertiary amine derivative is a compound represented by the following general formula [3]. General formula [3] [In the formula, B ^{1 to} B ⁴ each independently represent a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. G
Represents a substituted or unsubstituted arylene group. ] 7. The organic electroluminescence device according to claim 4, wherein a layer containing a metal complex compound or a nitrogen-containing five-membered ring derivative is formed between the light emitting layer and the cathode. 8. The organic electroluminescent device according to claim 4, wherein the metal complex compound is a compound represented by the following general formula [4]. General formula [4] [Wherein Q ¹ and Q ² each independently represent a substituted or unsubstituted hydroxyquinoline derivative or a substituted or unsubstituted hydroxybenzoquinoline derivative;
Is a halogen atom, a substituted or unsubstituted alkyl group,
A substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group optionally containing a nitrogen atom, -OR
(R is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, or a substituted or unsubstituted aryl group which may contain a nitrogen atom.),
Represents a ligand represented by —O—Ga—Q ³ (Q ⁴ ) (Q ³ and Q ⁴ have the same meaning as Q ¹ and Q ² ). ]