JP2001284061A - Organic electroluminescent element and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescent element which can be driven on a low voltage and a manufacturing method of the same. SOLUTION: The organic electroluminescent element composed of a P-type layer as an anode, a luminous layer formed on the anode layer, and a cathode formed on the luminous layer, and a manufacturing method of the same are provided. The P-typed transparent conductive layer is made of the material represented in the chemical formula: M1M2O2, hereupon, M1 represents either one of Cu, Ag, Au and M2 represents metal atom of 3 valence.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an organic electroluminescence device and a method of manufacturing the same, and more particularly, to an organic electroluminescence device using a P-type transparent conductive film as an anode and a method of manufacturing the same.

[0002]

2. Description of the Related Art At present, an organic electroluminescence element has been receiving attention. Organic electroluminescent elements emit surface light, emit light with high luminance even at a low applied voltage, can be made thinner and lighter, have high manufacturability of large-area light-emitting elements, and have a wide variety of light-emitting materials. Can be combined and used, so that full color display is highly feasible.

[0003] Organic electroluminescent elements are used as direction indicators for automobiles and bicycles, tail lamps, displays such as personal computers and family computers, backlights for liquid crystal display devices, light emitting elements for toys, and night indicator lights for road construction. It is expected to be used for

In an organic electroluminescence device,
Emitting light with high brightness for practical use in the above applications,
In addition, there is a demand for driving with a low applied voltage.

Conventionally, a single-layer organic electroluminescent device having a structure of anode / light-emitting layer / cathode has been known as an organic electroluminescent device. This organic electroluminescent element emits light according to the following principle. Electrons are injected into the light emitting layer from the cathode. Holes are injected into the light emitting layer from the anode. When the injected electrons and holes recombine in the light emitting layer, the organic electroluminescent element emits light.

In addition, organic electroluminescent devices having various structures have been developed. For example, anode /
An organic electroluminescent element having a multilayer laminated structure composed of a hole transport layer / a light emitting layer / an electron transport layer / a cathode is exemplified. Here, each layer of the hole transport layer / light emitting layer / electron transport layer is formed as a thin film.

[0007] The hole transport layer is a layer for transporting holes injected from the anode to the light emitting layer. The electron transport layer is a layer for transporting electrons injected from the cathode to the light emitting layer. The light emitting layer is provided between the hole transport layer and the electron transport layer. The light emitting layer contains a light emitting agent. The light emitting layer has this light emitting agent dispersed in a low molecular or high molecular compound. This luminescent agent comprises a fluorescent substance. In particular, it is desirable that the light emitting layer is made of a single fluorescent substance having a high emission quantum efficiency.
The luminescent agent is arbitrarily selected from a dye for a dye laser, a fluorescent whitening agent, or a fluorescent substance that emits fluorescence when irradiated with ultraviolet light.

[0008] In addition, an organic electroluminescent device having a multilayer laminated structure and including at least one of a hole blocking layer, an electron injection layer, and a hole injection layer has been conventionally known.

[0009] The hole blocking layer is provided between the light emitting layer and the cathode. When the organic electroluminescence element does not include the hole blocking layer, holes that do not contribute to light emission in the light emitting layer pass through the light emitting layer to reach the cathode. The hole blocking layer traps holes that do not contribute to light emission in the light emitting layer. As a result, the organic electroluminescence element including the hole blocking layer enables many holes contributing to light emission to be confined in the light emitting layer. For this reason, the above-mentioned organic electroluminescence element obtains high luminous efficiency in the light emitting layer.

The electron injection layer is provided between the light emitting layer and the cathode or between the hole blocking layer and the cathode. The electron injection layer facilitates injection of electrons from the cathode into the light emitting layer. The hole injection layer is provided between the light emitting layer and the anode. The hole injection layer facilitates injection of holes from the anode into the light emitting layer.

As a material for a transparent electrode of a conventional organic electroluminescence element, indium tin oxide (ITO) having N-type conductivity is generally used.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic electroluminescent device which can be driven by a low applied voltage and a method for manufacturing the same.

Another object of the present invention is to provide a semiconductor device in which the hole injection is performed using ITO.
It is an object of the present invention to provide an organic electroluminescence device using an anode made of a more efficient material and a method for manufacturing the same.

Still another object of the present invention is to provide an organic electroluminescent device having an anode made of a transparent conductive film having P-type conductivity, and a method of manufacturing the same.

[0015]

Means for solving the problem are described as follows. The technical matters corresponding to the claims in the expression are appended with numbers, symbols, etc. in parentheses (). The numbers, symbols, etc. clarify the correspondence / correspondence between the technical matters corresponding to the claims and at least one of the plural / forms of implementation.
It is not intended to show that the technical matters corresponding to the claims are limited to the technical matters of the embodiment.

According to the present invention, there is provided an anode (1) made of a P-type transparent conductive film, a light-emitting layer (2) provided on the anode (1), and a light-emitting layer (2). And (3) an organic electroluminescence element comprising: a cathode (3) provided thereon;

[0017] In the organic electroluminescent device, a transparent conductive film is made of a material represented by Chemical Formula M1M2O _2, M1 is Cu, Ag, either Au,
M2 can consist of a trivalent metal atom.

In the above organic electroluminescence device, the transparent conductive film is made of CuBO ₂ , CuAl
O ₂ , CuGaO ₂ , CuInO ₂ , CuTlO ₂ , A
_{gBO 2, AgAlO 2, AgGaO 2} , AgIn
O ₂ , AgTlO ₂ , AuBO ₂ , AuAlO ₂ , Au
It can be made of a material selected from GaO ₂ , AuInO ₂ , and AuTlO ₂ .

Further, in the above-mentioned organic electroluminescence device, the light emitting layer (2) is provided with a hole transport layer (1).
2) and an electron transport layer (13) provided on the hole transport layer (12), wherein the hole transport material constituting the hole transport layer (12) has an ionization potential of 5.4 eV or more. It is possible.

According to the present invention, in order to solve the above-mentioned problems, (a) forming a P-type transparent conductive film on a transparent insulating substrate; and (b) forming a light emitting layer on the transparent conductive film. And (c) forming a cathode on the light-emitting layer.

In the above method for manufacturing an organic electroluminescence device, the transparent conductive film may have a chemical formula of M1M2O.
₂ wherein M1 is Cu, A
Either g or Au, M2 can be composed of a trivalent metal atom.

In the above method for manufacturing an organic electroluminescence device, the transparent conductive film is made of CuBO ₂ , Cu
AlO ₂ , CuGaO ₂ , CuInO ₂ , CuTl
_{O 2, AgBO 2, AgAlO 2} , AgGaO 2, Ag
InO ₂ , AgTlO ₂ , AuBO ₂ , AuAlO ₂ ,
It can be made of a material selected from any of AuGaO ₂ , AuInO ₂ , and AuTlO ₂ .

In the above method for manufacturing an organic electroluminescence device, the step (a) is performed in accordance with the chemical formula M1M
The method can include a step of forming a target of a material represented by 2O ₂ and a step of forming a P-type transparent conductive film on a transparent insulating substrate by a sputtering method using the target.

In the above method for manufacturing an organic electroluminescence device, the step (b) comprises forming a hole transport layer on a P-type transparent conductive film, and the hole forming the hole transport layer. The transport material has an ionization potential of 5.4 eV or more, and may include a step of forming an electron transport layer on the hole transport layer.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an organic electroluminescence device according to the present invention will be described with reference to the drawings.

FIG. 1 shows a first embodiment of the organic electroluminescence device according to the present invention. The first embodiment of the organic electroluminescence device according to the present invention comprises an anode 1, a bipolar light emitting layer 2, and a cathode 3. Bipolar light emitting layer 2 is formed on anode 1. The cathode 3 is formed on the bipolar light emitting layer 2.

The anode 1 is made of a transparent P-type conductive material formed on a transparent insulating support such as a glass substrate.
Material of the anode 1 is represented by Formula M1M2O _2. Here, M1 is any of Cu, Ag, and Au, and M2 is a trivalent metal atom. In particular, the material of the anode 1 is CuB
O ₂ , CuAlO ₂ , CuGaO ₂ , CuInO ₂ , C
_{uTlO 2, AgBO 2, AgAlO 2} , AgGa
O ₂ , AgInO ₂ , AgTlO ₂ , AuBO ₂ , Au
AlO ₂ , AuGaO ₂ , AuInO ₂ , AuTlO ₂
Selected from any of the following.

The bipolar light emitting layer 2 contains a hole transporting agent and / or an electron transporting agent. Further, the bipolar light emitting layer 2 can contain a fluorescent substance as a doped light emitting material dispersed therein. Further, the bipolar light emitting layer 2 may include a binder polymer.

The hole transporting agent comprises a hole transporting organic substance. The hole transporting organic substance is composed of a hole transporting low molecule or a hole transporting polymer.

The hole transporting small molecule is

Embedded image N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1'-biphenyl-4,4'-diamine shown below (hereinafter also referred to as TPD)

Embedded image 4,4'-bis (9-carbazolyl) biphenyl shown in

Embedded image N, N'-diphenyl-N, N'-bis (1-naphthyl) -1,1'-biphenyl-4,4'-diamine shown in

Embedded image 4,4'-bis (10-phenothiazinyl) biphenyl shown in

Embedded image Copper phthalocyanine, shown in

Embedded image TPAC shown in

Embedded image PDA shown in

Embedded image And the derivatives of the above compounds.

The hole transporting polymer is

Embedded image Poly (N-vinylcarbazole) (hereinafter also referred to as PVK), polyvinylnaphthalene, polyvinylanthracene, polyvinylphenanthrene, polyvinylpyrene,
It is preferable to be selected from polyvinyl perylene.

Alternatively, the hole transporting polymer is poly (paraphenylene) and its derivative,

Embedded image Conductive polymer light-emitting materials such as poly (para-phenylenevinylene) (PPV) and its derivatives shown in

Embedded image PTPDMA represented by the chemical formula [Formula 11] and derivatives thereof,

Embedded image A compound represented by the chemical formula [Formula 12] and a derivative thereof,

Embedded image A compound represented by the chemical formula [Formula 13] and a derivative thereof,

Embedded image A compound represented by the chemical formula [Formula 14] and a derivative thereof,

Embedded image PTPDEK represented by the chemical formula [Formula 15] and derivatives thereof,

Embedded image PTPDES represented by the chemical formula [Formula 16] and derivatives thereof,

Embedded image PTPDBPA represented by the chemical formula [Formula 17] and derivatives thereof,

Embedded image PTPDEK2 represented by the chemical formula [Formula 18] and derivatives thereof,

Embedded image It is preferable to select from conductive polymer light-emitting materials such as PTPDES2 represented by the chemical formula [Formula 19] and derivatives thereof.

The electron transporting agent comprises an electron transporting low molecule or an electron transporting polymer.

The electron transporting small molecule is

Embedded image Tris (8-hydroxyquinolinato) aluminum shown in [Chemical Formula 20] (hereinafter also referred to as Alq3)

Embedded image 3- (4-biphenylyl) -5- (4
-Tert-butylphenyl) -4-phenyl-1,
2,4-triazole (hereinafter also referred to as TAZ),

Embedded image 2- (4-biphenylyl) -5- (4
-Tert-butylphenyl) -1,3,4-oxadiazole (hereinafter also referred to as PBD)

Embedded image 4,4′-bis (1,1-diphenylethenyl) biphenyl (hereinafter also referred to as DPVBi) shown in [Formula 23],

Embedded image 2,5-bis (1-naphthyl) -1 shown in [Formula 24].
3.4-oxadiazole (hereinafter also referred to as BND)

Embedded image 4,4′-bis (1,1-bis (4-methylphenyl) ethenyl) biphenyl (hereinafter referred to as D
TVBi),

Embedded image 2,5-bis (4-biphenylyl) -1,3,4-oxadiazole (hereinafter also referred to as BBD) shown in [Chemical Formula 26] and the like.

The electron transporting polymer is

Embedded image

Embedded image An oxadiazole-based polymer compound represented by the following [Formula 27] or [Formula 28],

Embedded image

Embedded image It is selected from triazole-based polymer compounds as shown in [Formula 29] and [Formula 30].

The fluorescent substances are coumarin 1, coumarin 2, coumarin 6, coumarin 7, coumarin 30, coumarin 10
2. Coumarin 106, Coumarin 334, Coumarin 33
7, Coumarin 4, Coumarin 314, Coumarin 153, Coumarin 3CA, Coumarin 307, Coumarin 314T, Coumarin 338, Coumarin 500, Coumarin 138, Coumarin 152, Coumarin 151, Coumarin 339, 3-
(2-benzothiazolyl) -7- (dibutylamino) coumarin, 3- (2-benzothiazolyl) -7- (diheptylamino) coumarin, 3- (2-benzothiazolyl)
-7- (Dioctylamino) coumarin, 10- (2-benzothiazolyl) -2,3,6,7-tetrahydro-
1,1,7,7-tetramethyl 1H, 5H, 11H-
[1] Benzopyrano [6,7,8-ij] coumarin-1
Coumarin derivatives such as 1-One,

Embedded image (2- (2- (4- (dimethylamino) phenyl) ethenyl) -6-methyl-4H-pyran-4-ylidene) propanedinitrile (hereinafter also referred to as DCM),
(2- (2- (4- (dipropylamino) phenyl) ethenyl) -6-methyl-4H-pyran-4-ylidene)
Propandinitrile, (2- (2- (4- (dibutylamino) phenyl) ethenyl) -6-methyl-4H-pyran-4-ylidene) propanedinitrile, (2- (2-
(4- (dioctylamino) phenyl) ethenyl) -6
-Methyl-4H-pyran-4-iridene) propanedinitrile

Embedded image

Embedded image

Embedded image DCM compounds such as compounds represented by chemical formulas [Formula 32], [Formula 33] and [Formula 34],

Embedded image

Embedded image Compounds represented by the chemical formulas [Formula 35] and [Formula 36], dyes such as Nile Red, 5,6,11,12-tetraphenylnaphthacene (hereinafter also referred to as rubrene), quinacridone, aromatic compounds, anthracene, and anine Aromatic amines, derivatives of aromatic imines,

Embedded image 1,1,4,4-tetraphenyl-1,3-butadiene (hereinafter also referred to as TPB), 1- (9-anthracenyl) -4-phenyl-1,3-butadiene, 1- (4
-Quinolyl) -4- (P-dimethylamino) phenyl-
Butadiene derivatives such as 1,3-butadiene, acridine derivatives, stilbene derivatives such as 4,4′-bis (5-methyl-2-benzooxazolyl) stilbene,
Derivatives of isobenzofuran such as 1,3-isobenzofuran, excimers such as 1,3-dipyrenylpropane or compounds exhibiting exciplex emission, 7-
Benzoxadiazole derivatives such as (p-methoxybenzylamino) -4-nitrobenzoxadiazole,
Fluorescent brighteners such as oxazole, oxadiazol, benzimidazole and thiazole derivatives, metal complexes of 8-hydroxyquinoline and its derivatives, ruthenium complexes, rare earth complexes, benzoyltrifluoroacetone, fluoryltrifluoroacetone, eurobium of hexafluoroacetone It is selected from a fluorescent metal complex represented by a complex, a rare earth complex, or a rare earth salt such as terbium picolinate.

The binder polymer is polystyrene,
Polyvinyl biphenyl, polyvinyl phenanthrene, polyvinyl anthracene, polyvinyl perylene, poly (ethylene-co-vinyl acetate), polybutadiene
cis and trans, poly (2-vinylnaphthalene), polyvinylpyrrolidone, polystyrene, poly (methyl methacrylate), poly (vinyl acetate), poly (2-vinylpyridine-co-styrene), polyacenaphthylene, poly (acrylonitrile-) co-butadiene), poly (benzyl methacrylate), poly (vinyltoluene), poly (styrene-co-acrylonitrile), poly (4-
Vinyl biphenyl) and polyethylene glycol.

The cathode 3 is made of a conductive cathode material. The cathode material is selected from metals such as indium, silver, gold, copper, tin, aluminum, lead, magnesium, lithium, lanthanum, europium, and ytterbium, rare earths alone, lithium fluoride, and composites thereof. Cathode 3 may be translucent or opaque.

Next, a method of manufacturing the organic electroluminescence device according to the first embodiment of the present invention will be described.

First, the anode 1 is formed on a glass substrate by an evaporation method using an anode material as a target. Here, the method of forming this target is described in Hiroshi Kawasoe, “Chemical Design of Wide-Gap P-Type Conductive Oxide”, Solid Physics vol.33, No.11, 1
998, pp. 937-943.

Next, a solution is prepared in which at least one of the hole transporting agent and the electron transporting agent is dissolved or dispersed in a solvent. Further, this solution may dissolve or disperse the fluorescent substance shown above or the binder polymer shown above. The bipolar light emitting layer 2 is formed on the anode 1 by a wet method using this solution. At this time, the solvent is removed from the bipolar light emitting layer 2 by evaporating by natural drying or heat drying.

In the wet method described above, it is not necessary to carry out processes such as polymerization and curing by heating and irradiation of ultraviolet rays. Therefore,
The wet method described above has a simplified manufacturing process and can improve production efficiency.

The wet method includes, for example, a casting method, a blade coating method, a dip coating method, a spin coating method,
Includes normal coating methods such as spray coating and roll coating.

Finally, the cathode 3 is formed on the bipolar light emitting layer 2 by an evaporation method using a cathode material.

In the above-described method for producing an organic electroluminescence device, the solvent used for forming the bipolar light emitting layer is a general organic solvent, and at least one of the hole transporting agent and the electron transporting agent is dissolved or dispersed therein. A choice is made from the possibilities. Further, the solvent may be any solvent that can further dissolve or disperse the binder polymer. Examples of the solvent to be used include one or a mixture of two or more of the following solvents. Examples of the solvent include alcohols such as methanol, ethanol and isopropyl alcohol, ketones such as acetone and methyl ethyl ketone, N, N dimethylformaldehyde, N, N
Dimethylacetaldehyde, amides such as N-methylpyrrolidinone, tetrahydrofuran, dioxoic acid, ethers such as ethylene glycol monomethyl ether, n-methylamine, pyrididine, quinoline, amines such as aniline,
m-cresol, α-chloronaphthalene, 2,2-dimethylbutane, 2,4-dimethylpentane, 2-methylhexane, 3-methylhexane, 2,2,4-trimethylpentane, 2-methylbutane, 2,2, 5-trimethylhexane, 1,1,2-trichloro-1,2,2-trifluoroethane, 1-pentene, 2,2,3-trimethylpentane, 2-methylpentane, n-pentane, tr
ans-2-pentene, 1-hexene, cis-2-pentene, 2-chloro-2-methylpropane, 1,1,
2,2-tetrachloro-1,2-difluoroethane, 1
-Heptene, hexane, n-octane, 1-octene,
Heptane, n-nonane, 1-nonene, n-decane, 1-
Chloropentane, 1-decene, 2-chlorobutane, benzotrifluoride, methylcyclohexane, methylcyclopentane, 2-chloropropane, mesitylene, 1-chlorobutane, ethylcyclohexane, p-xylene, m
-Xylene, 2-bromopropane, cyclohexene, cyclopentane, 1-chloropropane, cyclohexane,
2,3-dimethylbutane, o-xylene, tetrachloromethane, hexafluorobenzene, pentachloroethane, 1-chloro-2-methylpropane, 1,1-dichloroethylene, 1,1,1,2-tetrachloroethane,
1,1,1-trichloroethane, 1-bromopropane,
Cumene, p-chlorotoluene, diethyl sulfide,
o-chlorotoluene, p-dichlorobenzene, 1,1-
Dichloroethane, tetrachloroethylene, m-dichlorobenzene, p-diethylbenzene, m-diethylbenzene, ethylbenzene, trichloroethylene, 3-chloropropene, o-diethylbenzene, o-dichlorobenzene, bromoethane, toluene, chlorobenzene, trichloromethane, fluorobenzene, 1,2 -Dichloroethylene (trans), 1,1,2,2-tetrachloroethane, 1.2-dichloropropane, benzene, 1,2,2
3-trichloropropane, styrene, isobutyronitrile, 1,2-dichloroethylene (cis), 1-bromo-2-chloroethane, 1,2-dichloroethane, hexachloroethylene, 1,2-dibromoethane, 1,1,2
-Trichloroethane, dichloromethane, valeronitrile, thiophene, carbon disulfide, chlorobromomethane, bromobenzene, 2-nitropropane, 1-
Examples include nitropropane, benzonitrile, nitroethane, and the like, and a mixed solvent thereof.

Further, using a solvent that easily dissolves water,
When the bipolar light-emitting layer 2 is formed by a wet method, moisture in the solvent remains in the bipolar light-emitting layer 2 itself. As a result, the light emitting characteristics of the bipolar light emitting layer 2 itself deteriorate. By reducing or eliminating the influence of such deterioration, the durability of the bipolar light emitting layer 2 can be improved. For this purpose, it is desirable to use a solvent in which the solubility of water in the solvent used in the wet method is less than a certain ratio at room temperature (normal temperature). In particular, it is desirable for the solvent to have a water solubility of 2 percent by weight or less. More preferably, the solvent has a water solubility of 1 percent by weight or less.

Such solvents include α-chloronaphthalene, 2,2-dimethylbutane, 2,4-dimethylpentane, 2-methylhexane, 3-methylhexane,
2,4-trimethylpentane, 2-methylbutane, 2,
2,5-trimethylhexane, 1,1,2-trichloro-1,2,2-trifluoroethane, 1-pentene,
2,2,3-trimethylpentane, 2-methylpentane, n-pentane, trans-2-pentene, 1-hexene, cis-2-pentene, 2-chloro-2-methylpropane, 1,1,2,2 -Tetrachloro-1,2-
Difluoroethane, 1-heptene, hexane, n-octane, 1-octene, heptane, n-nonane, 1-nonene, n-decane, 1-chloropentane, 1-decene, 2
-Chlorobutane, benzotrifluoride, methylcyclohexane, methylcyclopentane, 2-chloropropane, mesitylene, 1-chlorobutane, ethylcyclohexane, p-xylene, m-xylene, 2-bromopropane, cyclohexene, cyclopentane, 1-chloropropane, cyclohexane , 2,3-dimethylbutane, o-
Xylene, tetrachloromethane, hexafluorobenzene, pentachloroethane, 1-chloro-2-methylpropane, 1,1-dichloroethylene, 1,1,1,2-tetrachloroethane, 1,1,1-trichloroethane,
-Bromopropane, cumene, p-chlorotoluene, diethylsulfide, o-chlorotoluene, p-dichlorobenzene, 1,1-dichloroethane, tetrachloroethylene, m-dichlorobenzene, p-diethylbenzene,
m-diethylbenzene, ethylbenzene, trichloroethylene, 3-chloropropene, o-diethylbenzene,
o-dichlorobenzene, bromoethane, toluene, chlorobenzene, trichloromethane, fluorobenzene,
1,2-dichloroethylene (trans), 1,1,
2,2-tetrachloroethane, 1.2-dichloropropane, benzene, 1,2,3-trichloropropane, styrene, isobutyronitrile, 1,2-dichloroethylene (cis), 1-bromo-2-chloroethane, 1 , 2-
Dichloroethane, hexachloroethylene, 1,2-dibromoethane, 1,1,2-trichloroethane, dichloromethane, valeronitrile, thiophene, carbon disulfide, chlorobromomethane, bromobenzene, 2-
It is selected from nitropropane, 1-nitropropane, benzonitrile, nitroethane, and the like, and a mixed solvent thereof.

When a solution using a solvent having a strong hydrogen bond is left for a long time, the material in the solvent may be deteriorated. In order to prevent such deterioration of the material, it is preferable to use a solvent having a relatively weak hydrogen bond of the solvent itself, such as a hydrocarbon, a halogenated hydrocarbon, a nitrated hydrocarbon, or a nitrile. Such solvents include α-chloronaphthalene, 2,2-dimethylbutane, 2,4-dimethylpentane, 2-methylhexane, 3-methylhexane,
2,2,4-trimethylpentane, 2-methylbutane,
2,2,5-trimethylhexane, 1,1,2-trichloro-1,2,2-trifluoroethane, 1-pentene, 2,2,3-trimethylpentane, 2-methylpentane, n-pentane, trans -2-pentene, 1-
Hexene, cis-2-pentene, 2-chloro-2-methylpropane, 1,1,2,2-tetrachloro-1,2
-Difluoroethane, 1-heptene, hexane, n-octane, 1-octene, heptane, n-nonane, 1-nonene, n-decane, 1-chloropentane, 1-decene,
2-chlorobutane, benzotrifluoride, methylcyclohexane, methylcyclopentane, 2-chloropropane, mesitylene, 1-chlorobutane, ethylcyclohexane, p-xylene, m-xylene, 2-bromopropane, cyclohexene, cyclopentane, 1-chloropropane, Cyclohexane, 2,3-dimethylbutane, o-
Xylene, tetrachloromethane, hexafluorobenzene, pentachloroethane, 1-chloro-2-methylpropane, 1,1-dichloroethylene, 1,1,1,2-tetrachloroethane, 1,1,1-trichloroethane,
-Bromopropane, cumene, p-chlorotoluene, diethylsulfide, o-chlorotoluene, p-dichlorobenzene, 1,1-dichloroethane, tetrachloroethylene, m-dichlorobenzene, p-diethylbenzene,
m-diethylbenzene, ethylbenzene, trichloroethylene, 3-chloropropene, o-diethylbenzene,
o-dichlorobenzene, bromoethane, toluene, chlorobenzene, trichloromethane, fluorobenzene,
1,2-dichloroethylene (trans), 1,1,
2,2-tetrachloroethane, 1.2-dichloropropane, benzene, 1,2,3-trichloropropane, styrene, isobutyronitrile, 1,2-dichloroethylene (cis), 1-bromo-2-chloroethane, 1 , 2-
Dichloroethane, hexachloroethylene, 1,2-dibromoethane, 1,1,2-trichloroethane, dichloromethane, valeronitrile, thiophene, carbon disulfide, chlorobromomethane, bromobenzene, 2-
It is selected from nitropropane, 1-nitropropane, benzonitrile, nitroethane, and the like, and a mixed solvent thereof.

In particular, it is desirable to use a hydrocarbon solvent as a solvent that improves the durability of the element and does not deteriorate the material. Such hydrocarbon solvents include 2,2-dimethylbutane, 2,4-dimethylpentane, 2-methylhexane, 3-methylhexane, 2,2,4-trimethylpentane, 2-methylbutane, 2,2, 5-trimethylhexane, 1,1,2-trichloro-1,2,2-trifluoroethane, 1-pentene, 2,2,3-trimethylpentane, 2-methylpentane, n-pentane, tr
ans-2-pentene, 1-hexene, cis-2-pentene, 1-heptene, hexane, n-octane, 1-
Octene, heptane, n-nonane, 1-nonene, n-decane, 1-decene, methylcyclohexane, methylcyclopentane, mesitylene, ethylcyclohexane, p-
Xylene, m-xylene, cyclohexene, cyclopentane, cyclohexane, 2,3-dimethylbutane, o-
Xylene, cumene, p-diethylbenzene, m-diethylbenzene, ethylbenzene, o-diethylbenzene,
It is selected from toluene, benzene, styrene, and a mixed solvent thereof.

FIG. 2 shows a second embodiment of the organic electroluminescence device according to the present invention. In the second embodiment of the organic electroluminescence device according to the present invention, an anode 11, a hole transport layer 12, an electron transport layer 13
And a cathode 14. The hole transport layer 12 is formed on the anode 11. The electron transport layer 13 is a hole transport layer 12
Formed on top. The cathode 14 is formed on the electron transport layer 13.

The anode 11 and the cathode 14 have the same configuration as that of the first embodiment of the organic electroluminescence device according to the present invention.

The hole transporting layer 12 contains a hole transporting agent or a hole transporting polymer. Further, the hole transport layer can contain a fluorescent substance as a doped light emitting material dispersed therein. Further, the hole transport layer can include a binder polymer. Here, the hole transporting agent, the hole transporting polymer, the fluorescent substance, and the binder polymer are the same as those used in the first embodiment of the organic electroluminescence device of the present invention.

The electron transport layer 13 contains an electron transport agent. Further, the electron transporting layer can contain a fluorescent substance as a doping luminescent material dispersed therein. Further, the electron transport layer can include a binder polymer. here,
The electron transporting agent, the fluorescent substance, and the binder polymer are the same as those used in the first embodiment of the organic electroluminescence device of the present invention.

Next, a method of manufacturing an organic electroluminescence device according to a second embodiment of the present invention will be described.

First, the anode 1 is formed on a glass substrate by an evaporation method using an anode material as a target. Here, the method of forming the target is the same as the method of manufacturing the organic electroluminescence device according to the first embodiment of the present invention.

Next, a solution in which the hole transporting agent is dissolved or dispersed in a solvent is prepared. Further, this solution may dissolve or disperse the fluorescent substance shown above or the binder polymer shown above. The hole transport layer 12 is formed on the anode 11 by a wet method using this solution.
At this time, the solvent is removed by evaporation by natural drying or heat drying.

Next, a solution in which the electron transporting agent is dissolved or dispersed in a solvent is prepared. Further, this solution may dissolve or disperse the fluorescent substance shown above or the binder polymer shown above. The electron transport layer 13 is formed on the hole transport layer 12 by a wet method using this solution. At this time, the solvent is removed by evaporation by natural drying or heat drying.

The above wet method includes, for example, a casting method, a blade coating method, a dip coating method, a spin coating method,
Includes normal coating methods such as spray coating and roll coating.

Finally, the cathode 14 is formed on the electron transport layer 13 by an evaporation method using a cathode material.

Here, the solvent used for forming the hole transport layer 12 and the electron transport layer 13 is the same as that used in the method of manufacturing the organic electroluminescent device according to the first embodiment of the present invention. It is selected from the same solvents that are sometimes used.

Next, the organic electroluminescent device formed by the present inventors will be described below.

Example 1 First, a CuAlO ₂ target was formed by the following steps. 57.2 g of Cu ₂ O powder and 47.7 g of CuO powder are mixed. 102 g of Al ₂ O ₃ powder is mixed with this mixed powder. The mixture is fired in air at 1050 ° C. for 10 hours to obtain CuAlO ₂ powder. This CuAlO ₂ powder has a diameter of
Perform uniaxial molding in a 20 mm pellet. Uniaxially formed CuAlO ₂ powder is added to CIP (Cold Isos
taticalPress: cold isostatic pressing) The CIP-formed CuAlO ₂ powder is again heated in air at a temperature of 1050.
C. for 10 hours to obtain a CuAlO ₂ target.
Next, a 500 nm-thick transparent conductive film of CuAlO ₂ is formed on a glass substrate by a sputtering method using this target.

Next, as a hole transporting polymer, poly (N
A first solution is prepared by dissolving 6.9 mg of vinyl carbazole) in 1 ml of dichloroethane. A hole transport layer having a thickness of 50 nm is formed on the glass substrate by spin coating using the first solution. Here, the ionization energy of poly (N-vinyl carbazole) is 5.9 eV.

Next, 2- (4-biphenyl) -5- (4-tert-butylphenyl) -1, an electron transporting agent was used.
6.25 mg of 3,4-oxadiazole (PBD) and coumarin 6 were used as a fluorescent substance.
g, a second solution is prepared by dissolving 6.25 mg of polystyrene as a binder in 1 ml of ethylbenzene. An electron transporting light emitting layer having a thickness of 50 nm is formed on the hole transporting layer by a spin coating method using the second solution.

Finally, a cathode is formed on the electron transporting light emitting layer by a co-evaporation method in which Mg and Al are evaporated at a mass ratio of 10: 1 as a cathode material.

The organic electroluminescent device formed by the above process has a luminance of 150 cd at an applied voltage of 10 V.
/ showed m ^2. Further, in the organic electroluminescent device, the voltage applied to emit light at a luminance 100 cd / m ² is a 9.2 V, the current density at this time 2.0 mA /
It was cm ^2.

COMPARATIVE EXAMPLE 1 An organic electroluminescent device was produced in the same steps as in Example 1 except for the step of forming an anode in Example 1. As the anode in Comparative Example 1, a commercially available ITO substrate (made by Asahi Glass, 20 Ω / cm ² ) is used.

The organic electroluminescent device of Comparative Example 1 exhibited a luminance of 100 cd / m ² at an applied voltage of 10 V. Further, in this organic electroluminescence element,
The voltage applied to emit light at a luminance of 100 cd / m ² is 10.0
V, and the current density at this time was 2.0 mA / cm ² .

For this reason, the organic electroluminescence device of the present invention emits light with higher luminance than before, or is driven with a lower applied voltage.

Examples 2 to 15 In Examples 2 to 15, the anode material in Example 1 was changed.
Then, in the same process as in Example 1, the organic electroluminescent
Create a sense element. [Table 1] is for Examples 2 to 15.
The anode material used, the anode is formed using the anode material
10V to the organic EL device
Luminance obtained when voltage is applied, luminance 100 cd / m ^TwoTo emit light
Voltage required for brightness and brightness 100 cd / m^TwoEmits light
Shows the current density when

[0071]

[Table 1] The organic electroluminescence device according to the present invention formed in Examples 2 to 15 also emits light with higher luminance than before, or is driven with a lower applied voltage.

Embodiments 16 to 21 An organic electroluminescent device is manufactured in the same process as in Embodiment 1 except that the hole transport material used in forming the hole transport layer in Embodiment 1 is changed. [Table 2] shows that the hole transporting materials used in Examples 16 to 21, the ionization potential of the hole transporting materials, and the voltage of 10 V were applied to the organic electroluminescent device having the hole transporting layer formed using the hole transporting materials. Brightness obtained by applying, 100cd / m brightness
^The applied voltage value required to emit light in ² , and the organic electroluminescent elements corresponding to Examples 16 to 21 formed by changing the anode to ITO were changed to a luminance of 100 cd /
Indicates the applied voltage value required to emit light at m ² .

[0073]

[Table 2] In the organic electroluminescence devices of Examples 1 and 16 to 21, the applied voltage required to obtain the same luminance is 5 times higher than that of the conventional organic electroluminescence device.
~ 10% reduction. In particular, Examples 1 and 16 to 2
In the first organic electroluminescence device, a hole transport material having an ionization potential of 5.4 eV or more is used. For this reason, the organic electroluminescent device of the present invention using a hole transporting material having an ionization potential of 5.4 eV or more emits light with higher luminance than before or is driven with a lower applied voltage.

Example 22 In Example 22, an organic electroluminescent device comprising an anode / a bipolar light emitting layer / a cathode was formed.

First, an anode is formed. The method for forming the anode is the same as that in the first embodiment.

Next, a bipolar light emitting layer is formed. The material of the bipolar light emitting layer is poly (2-methoxy, 5- (2 ′
-Ethyl-hexyloxy) -1,4-phenylenevinylene (MEH-PPV). Here, MEH-PP
V is represented by the chemical formula [Formula 38].

[0077]

Embedded image A 100 nm-thick bipolar light emitting layer is formed on the hole injection layer by a spin coating method using a solution of MEH-PPV dissolved in a solvent.

Finally, a cathode is formed. A cathode is formed on the bipolar light emitting layer using an evaporation method using Ca as a cathode material.

The organic electroluminescent device formed in Example 22 had a luminance of 1,000 cd / m ² at an applied voltage of 5 V.
Flashed.

An organic electroluminescence device is formed in the same manner as in Example 22 except that ITO is used for the anode. The organic electroluminescent device emitted light at a luminance of 1,000 cd / m ² at an applied voltage of 5.2 V.

Example 23 In Example 23, an organic electroluminescent element was formed in the same steps as in Example 22 except for the step of forming a bipolar light emitting layer. The steps of forming the bipolar light emitting layer are described below. The material of the bipolar light emitting layer is a poly (fluorene-thiophene) copolymer represented by the chemical formula [Formula 39].

[0082]

Embedded image A 100 nm-thick bipolar light-emitting layer is formed on the anode by spin coating using a solution of 10 mg of a poly (fluorene-thiophene) copolymer dissolved in a solvent.

The organic electroluminescent device formed in Example 23 had a luminance of 100 cd / m ² when the applied voltage was 10 V.
Flashed.

An organic electroluminescence device is formed in the same process as in Example 23 except that ITO is used for the anode. This organic electroluminescent device emitted light at a luminance of 100 cd / m ² at an applied voltage of 11 V.

Example 24 In Example 24, an organic electroluminescence device comprising an anode / a hole transport layer / an electron transport layer / a cathode was formed.
The anode is formed in the same manner as in the first embodiment. The hole transport layer is formed by depositing a hole transport material with a thickness of 40 nm on the anode. This hole transporting layer material is composed of N, N′-diphenyl-N, N′-bis (3-methylphenyl) -1,1′-biphenyl-4,4′-diamine represented by the chemical formula [Chemical Formula 1]. TPD). The electron transport layer is formed by depositing an electron transport material with a thickness of 40 nm on the anode. This electron transport material is tris (8-hydroxyquinolinato) aluminum. The cathode uses Mg and Al for the cathode material.
g and Al are formed on the electron transport layer at a mass ratio of 10: 1 by a co-evaporation method.

The organic electroluminescent device formed in Example 24 had a luminance of 1,500 cd / m 2 at an applied voltage of 10 V.
Emitted in ² .

An organic electroluminescent device is formed in the same steps as in Example 24 except that ITO is used for the anode. The organic electroluminescent device emitted light at a luminance of 1,500 cd / m ² at an applied voltage of 10.3 V.

The organic electroluminescent devices of the present invention formed in Examples 22 to 24 are also driven at a lower applied voltage than before.

[0089]

The organic electroluminescent device of the present invention can be driven at a higher luminance or a lower applied voltage than the conventional organic electroluminescent device by using a transparent conductive film made of a P-type anode material for the anode. Has an effect.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of an organic electroluminescence element according to the present invention.

FIG. 2 shows a second embodiment of the organic electroluminescence element according to the present invention.

[Explanation of symbols]

 Reference Signs List 1,11 anode 2 bipolar light emitting layer 3,14 cathode 12 hole transport layer 13 electron transport layer

Continued on the front page (72) Inventor Koichiro Aikawa 1-10-1, Shinsayama, Sayama City, Saitama Prefecture Inside Honda Engineering Co., Ltd. (72) Inventor Akihiro Komatsuzaki 1-10-1, Shinsayama, Sayama City, Saitama Prefecture Honda Engineering (72) Inventor Yoichi Shimada 1-10-1 Shinsayama, Sayama-shi, Saitama Honda Engineering Co., Ltd. F-term (reference) 3K007 AB02 AB06 CA01 CB01 CB03 DA01 DB03 EB00 5G307 FA01 FB01 FC07

Claims (9)

[Claims] 1. An organic electroluminescent device comprising: an anode made of a P-type transparent conductive film; at least one layer provided on the anode, an organic layer serving as a light emitting layer, and a cathode provided on the organic layer. Luminescent element. In the organic electroluminescent device according to the claim 1, wherein the transparent conductive film is made of a material represented by Chemical Formula M1M2O _2, M1 is Cu, Ag, one of Au, M2 is a trivalent An organic electroluminescent device composed of metal atoms. 3. The organic electroluminescence device according to claim 2, wherein the transparent conductive film is made of CuBO ₂ , CuAlO ₂ , CuG.
aO ₂ , CuInO ₂ , CuTlO ₂ , AgBO ₂ , A
gAlO ₂ , AgGaO ₂ , AgInO ₂ , AgTlO
₂ , AuBO ₂ , AuAlO ₂ , AuGaO ₂ , AuI
An organic electroluminescence element made of a material selected from nO ₂ and AuTlO ₂ . 4. The organic electroluminescence device according to claim 1, wherein the organic layer includes a hole transport layer provided on the anode, and a hole transport material forming the hole transport layer. An organic electroluminescence device having an ionization potential of 5.4 eV or more. 5. A step of: (a) forming a P-type transparent conductive film on a transparent insulating substrate; and (b) forming at least one organic layer, which is a light emitting layer, on the transparent conductive film. (C) forming a cathode on the light emitting layer. 6. A method of manufacturing an organic electroluminescent device according to claim 5, wherein the transparent conductive film is made of a material represented by Chemical Formula M1M2O _2, wherein, M1 is Cu, Ag, one of Au, M2 Is a method for producing an organic electroluminescent device, comprising a trivalent metal atom. 7. The method for manufacturing an organic electroluminescence device according to claim 6, wherein the transparent conductive film is made of CuBO ₂ , CuAlO ₂ , CuG.
aO ₂ , CuInO ₂ , CuTlO ₂ , AgBO ₂ , A
gAlO ₂ , AgGaO ₂ , AgInO ₂ , AgTlO
₂ , AuBO ₂ , AuAlO ₂ , AuGaO ₂ , AuI
A method for manufacturing an organic electroluminescence device, comprising a material selected from nO ₂ and AuTlO ₂ . 8. The method for manufacturing an organic electroluminescence device according to claim 6, wherein the step (a) comprises: forming a target of a material represented by the chemical formula M1M2O ₂ ; and sputtering using the target. Forming a P-type transparent conductive film on a transparent insulating substrate by a method. 9. The method of manufacturing an organic electroluminescent device according to claim 5, wherein the step (b) comprises: forming a hole transport layer on the P-type transparent conductive film. Wherein the ion transport potential of the hole transport material constituting the hole transport layer is 5.4 eV or more, and comprising the step of forming an electron transport layer on the hole transport layer, the method for producing an organic electroluminescent element. .