JP2001351785A - Organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long-life organic EL element, capable of being driven by a low voltage, and obtaining easily luminescence in addition to high brightness and various colors. SOLUTION: This organic electroluminescent element has an organic layers, comprising one or more layers between a pair of positive electrode and a negative electrode at least one of which is transparent or translucent. In the element, one or more layers of the organic layers includes one or more kinds of compounds including one or more kinds of compound groups to the number of 1 to 4 selected from a group comprising aryl groups having a hydroxyl group and the carbon number of 6 to 20 and heterocyclic compound groups having a hydroxyl group and the carbon number of 4 to 20, and the compounds have molecular weights smaller than 2,000, and the total amount of the compounds is 0.02 wt.% or higher and 9 wt.% or smaller as compared with the weight of the layers including the compounds, and a layer (including the case where the layer is a part or the whole of the negative electrode) which contains an alkali metal or the like is formed adjacent to the layers including the compounds.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescence device (hereinafter, sometimes referred to as an organic EL device).

[0002]

2. Description of the Related Art Compared with conventional inorganic EL devices, organic EL devices are characterized in that they can be driven at a lower voltage, have higher luminance, and easily emit light of many colors. Many attempts have been reported on organic charge transport compounds [Japanese Journal of Applied Physics (Jpn. J. Appl. Phys.).
s. 27, L269 (1988)], [Journal of Applied Physics (J. App.)
l. Phys. Vol. 65, p. 3610 (1989)
Year)〕.

Further, among organic EL devices, a polymer light emitting device using a high molecular weight light emitting material (hereinafter referred to as a polymer fluorescent substance) is disclosed in WO 9013148, JP-A-3-244630,・ Physics ・
Letters (Appl. Phys. Lett.) No. 58
Vol., 1982 (1991).
The polymeric fluorescent substance or its precursor is soluble in a solvent,
There is an advantage that a light emitting layer can be formed by a coating method.

In order to improve the performance such as the life of the organic EL device including the above-mentioned polymer light emitting device, Japanese Patent Application Laid-Open No. 9-1068 has been proposed.
No. 89, JP-A-9-125054, JP-A-1
Japanese Patent Application No. 0-255981 describes that a phenolic additive or the like is added to the organic layer of the device.

However, in order to further enhance the practicability of the organic EL device, it is necessary to maintain the characteristics of the organic EL device such that it can easily emit light of many colors in addition to low voltage driving and high luminance. There was a demand for a longer life.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an organic EL device which can easily emit light of many colors in addition to driving at a low voltage and high luminance. An EL element is provided.

[0007]

In view of such circumstances, the present inventors have at least one organic layer between a pair of anodes and cathodes, at least one of which is transparent or translucent. In an organic EL device, at least one of the organic layers contains a specific compound in a specific amount,
In addition, the present inventors have found that providing a specific layer adjacent to a layer containing the compound can further extend the life of the organic EL device, and have accomplished the present invention.

That is, the present invention provides the following [1] to [5]
It is related to. [1] In an organic electroluminescence device having at least one organic layer between an electrode composed of a pair of anodes and cathodes, at least one of which is transparent or translucent, at least one of the organic layers has a carbon group having a hydroxyl group. An aryl group having 6 to 20 carbon atoms and a hydroxyl group having 4 carbon atoms
A compound containing from 1 to 4 at least one compound group selected from the group consisting of up to 20 heterocyclic compound groups (hereinafter sometimes referred to as a compound group having a hydroxyl group); Is a compound having a molecular weight of 2,000 or less, wherein the total amount of the compounds is 0.02% by weight or more and 9% by weight or less based on the weight of the layer containing the compound, and is adjacent to the layer containing the compound. And an organic electroluminescent element provided with a layer containing an alkali metal, an alloy containing an alkali metal, or a compound containing an alkali metal (including a case where the layer is part or all of a cathode). [2] A planar light source using the organic electroluminescent device of [1]. [3] A segment display device using the organic electroluminescence device of [1]. [4] A dot matrix display device using the organic electroluminescence device of [1]. [5] A liquid crystal display device using the organic electroluminescence element of [1] as a backlight.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the organic EL device of the present invention will be described in detail. The organic EL device of the present invention is an organic electroluminescence device having at least one organic layer between an electrode composed of a pair of anodes and cathodes, at least one of which is transparent or translucent, wherein at least one of the organic layers is At least one compound group selected from the group consisting of an aryl group having 6 to 20 carbon atoms having a hydroxyl group and a heterocyclic compound group having 4 to 20 carbon atoms having a hydroxyl group (hereinafter referred to as a compound group having a hydroxyl group; Is a compound having a molecular weight of 2,000 or less, and the total amount of the compounds is 0.02 to the weight of the layer containing the compound. An alkali metal, an alloy containing an alkali metal, or an alkali metal, which is not less than 9% by weight and not more than 9% by weight and is adjacent to a layer containing the compound; Layer containing a compound containing, characterized in that a (said layer including those which are part or all of the cathode).

The organic EL device of the present invention has at least a light emitting layer, and may further have one or more layers selected from a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer. . As the organic EL device of the present invention, at least one of the layers containing an additive (compound having a molecular weight of 2000 or less) is used.
Those in which the layer is a light emitting layer are preferred.

The present invention also provides a light emitting layer, a hole transporting layer,
The use of two or more electron transport layers is also exemplified. The position of each of these layers in the device, from the cathode to the anode,
In general, an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, a hole injection layer, and an anode are used in this order. Is omitted. When a plurality of layers are used, the second layer
There is no particular limitation on the position where the layer is used, and the layer can be appropriately used in consideration of luminous efficiency and device life.

The additives used in the organic EL device of the present invention include:
It is a compound containing at least one compound containing 1 to 4 hydroxyl-containing compound groups and having a molecular weight of 2000 or less, preferably having 2 to 4 hydroxyl-containing compound groups, and having a molecular weight of 2 to 4. Those having 300 or more and 1200 or less are preferable. Further, the melting point of the additive is preferably 100 ° C. or higher.

Among the compound groups having a hydroxyl group, the aryl group having a hydroxyl group and having 6 to 20 carbon atoms may have at least one hydroxyl group in the aryl group. Examples of the aryl group include a phenyl group and a naphthyl group. Groups, anthryl groups, phenanthryl groups, etc., which are further substituted with one or more straight-chain, branched or cyclic alkyl groups having 1 to 20 carbon atoms, An alkoxy group having a chain, branched or cyclic alkyl group, an aryl group having 6 to 20 carbon atoms, a heterocyclic compound group having 2 to 20 carbon atoms, a carboxyl group, an acyl group, an amino group,
It may have a substituent selected from the group consisting of a nitro group, a cyano group and a halogen atom. Where linear,
An alkoxy group having a branched or cyclic alkyl group means that the alkyl group constituting the alkoxy group is a linear, branched or cyclic alkyl group (the same applies hereinafter). Among them, a group represented by the following general formula (1) is preferable.

Embedded image [Here, Ar ₁ represents an aryl group having 6 to 20 carbon atoms. R ₁ represents a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms or an alkoxy group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms;
Represents an integer of 1 to 3, and n represents 0 or an integer of 1 or more.
When n is 2 or more, R ₁ may be the same or different. (M + n) ≦ (the number of hydrogen atoms possessed when Ar ₁ is unsubstituted). ]

Further, among the compound groups having a hydroxyl group,
As the heterocyclic compound group having 4 to 20 carbon atoms having a hydroxyl group, it is sufficient that the heterocyclic compound group has at least one hydroxyl group. , A pyrazyl group,
Piperazyl group, quinolyl group, isoquinolyl group, quinoxalyl group, cinnolyl group, quinazolyl group, indolyl group,
Acrylol group, quinolyl group in which an aromatic ring is fused, isoquinolyl group in which an aromatic ring is fused, phenazyl group,
Carbazoyl, furyl, benzofuryl, dibenzofuryl, thienyl, benzothienyl, dibenzothienyl, dibenzothiazolyl, oxadiazolyl, oxazolyl, triazolyl, thiodiazolyl, benzoxazolyl, benzodiazolyl , A silolyl group, a benzosilolyl group, a chromone group, a flavone group, and the like. The group further includes one or more linear, branched or cyclic alkyl groups having 1 to 20 carbon atoms as substituents, Alkoxy group having 1 to 20 linear, branched or cyclic alkyl groups, aryl group having 6 to 20 carbon atoms, heterocyclic compound group having 2 to 20 carbon atoms, carboxyl group, acyl group, amino group, nitro group Group, a cyano group and a halogen atom. Among them, may have a substituent, a quinolyl group, an isoquinolyl group, a cinnolyl group, a quinoxalyl group, a quinazolyl group, a quinolyl group in which an aromatic ring is fused, and an isoquinolyl group in which an aromatic ring is fused. Preferably, a quinolyl group which may have a substituent,
A quinolyl group in which an aromatic ring is fused, an isoquinolyl group,
An isoquinolyl group in which an aromatic ring is fused is particularly preferred.

Next, the substituents of the compound having a hydroxyl group will be described more specifically. Among the substituents, examples of the linear, branched or cyclic alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an iso group.
-Propyl group, n-butyl group, iso-butyl group, te
rt-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, lauryl group, cyclopropyl group, cyclobutyl group, cyclopentyl group,
Examples thereof include a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, and a cyclododecyl group, and a methyl group, an ethyl group, and a tert-butyl group are preferable. In addition, when the example which does not describe prefixes, such as n- and iso-, is given as an alkyl group, the example illustrates all the alkyl groups of a linear structure and a branched structure. (The same applies hereinafter).

Examples of the alkoxy group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, an n-propyloxy group, an iso-propyloxy group, an n-butoxy group, an iso-butoxy group,
tert-butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, nonyloxy group, decyloxy group, lauryloxy group, cyclopropyloxy group, cyclobutyloxy group, cyclopentyloxy group, cyclohexyloxy group, cyclo Heptyloxy group and the like, methoxy group, ethoxy group,
An iso-propyloxy group and a tert-butoxy group are preferred.

The aryl group having 6 to 20 carbon atoms includes a phenyl group and a C ₁ -C ₁₂ alkoxyphenyl group (C ₁ -C ₁₂
Indicates that the number of carbon atoms is 1 to 12. The same applies to the following. ), C ₁ -C ₁₂ alkylphenyl group, 1-naphthyl, 2-naphthyl, anthryl group, etc. phenanthryl group and the like, a phenyl group, the C ₁ -C ₁₂ alkylphenyl group are preferable.

Examples of the heterocyclic compound group having 2 to 20 carbon atoms include a pyrrolyl group, a pyridyl group, a pyridazyl group, a pyrazyl group, a piperazyl group, a quinolyl group, an isoquinolyl group, a quinoxalyl group, a cinnolyl group, a quinazolyl group, an indolyl group, and an acridyl group. Group, phenazyl group, carbazoyl group, furyl group, benzofuryl group, dibenzofuryl group, thienyl group, benzothienyl group, dibenzothienyl group, oxadiazolyl group, oxazolyl group, triazolyl group, thiodiazolyl group, benzoxazolyl group, benzodiazolyl group, Examples include a silyl group, a benzosilolyl group, a chromone group, and a flavone group. Thienyl, pyridyl, quinolyl, isoquinolyl, triazolyl, oxadiazolyl, thiodiazolyl, benzodiazolyl, and benzooxadiazoli Group, benzothiophenyl diazo Lil group.

Next, the portion of the additive used in the present invention other than the compound having a hydroxyl group will be described. The moiety includes a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, ~
An aryl group optionally having 20 substituents, having 2 carbon atoms
A heterocyclic compound group, a carboxyl group, an acyl group, an amino group, a nitro group, a cyano group, or a halogen atom which may have a substituent of up to 20; The compound group may be further connected with one or more divalent, trivalent or tetravalent linking groups. Further, a compound group having a plurality of hydroxyl groups may be directly bonded, or may be connected by one or more divalent, trivalent or tetravalent linking groups.

The divalent linking group includes a group having 1 to 2 carbon atoms.
An alkylene group of 0, an alkylidene group having 1 to 20 carbon atoms,
An alkenylene group having 1 to 20 carbon atoms, an alkynylene group having 1 to 20 carbon atoms, an arylene group having 6 to 20 carbon atoms, an alkylenedioxy group having 1 to 20 carbon atoms, an arylenedioxy group having 6 to 20 carbon atoms, Examples thereof include a divalent alcohol residue, a carbonyl group, a divalent acyl group, an imino group, an azo group, and a group represented by the following formula (4). Here, R ′ is a hydrogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, or an alkoxy group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms. , Carbon number 6-2
An aryl group optionally having 0 substituents, having 2 to 2 carbon atoms
A heterocyclic compound group which may have 20 substituents, a carboxyl group, an acyl group, an amino group, a nitro group, a cyano group and a halogen group, and Ar ′ is a hydrocarbon having 6 to 60 carbon atoms. Represents a group.

Embedded image

The trivalent linking group is preferably a group having 1 to 2 carbon atoms.
Examples include an alkylidyl group of 0, an alkyltriyl group having 3 to 20 carbon atoms, a trivalent alcohol residue, a trivalent acyl group, and a group represented by the following formula (5).

Embedded image

Examples of the tetravalent linking group include an alkyltetrayl group having 3 to 20 carbon atoms, a tetravalent alcohol residue, a tetravalent acyl group, and a group represented by the following formula (6).

Embedded image

Next, specific examples of the additives used in the organic EL device of the present invention will be described. Among the additives, compounds containing an aryl group having a hydroxyl group include 2,6-di-te
rt-butylphenol, 2,4-di-tert-butylphenol, 2-tert-butyl-4-methoxyphenol, 2-tert-butyl-4,6-di-methylphenol, 2,6-di-tert-butyl- 4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,4,6-tri-tert-butylphenol, 2,6-di-tert-butyl-4-hydroxymethylphenol, 2, 6-di-tert-butyl-2-dimethylamino-p-cresol, 2,5-di-tert-butylhydroquinone, 2,5-di-ter
t-amylhydroquinone, n-octadecyl-3-
(3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t
tert-butylanilino) -1,3,5-triazine,
Phenol substituted with a 1-phenylethyl group, phenol substituted with a 1-phenylethyl group and a methyl group, 2-tert-butyl-6- (3′-tert-butyl-5′-methyl-2′-hydroxy Benzyl) -4
-Methylphenyl acrylate, 2,2'-methylene-
Bis- (4-methyl-6-tert-butylphenol), 2,2′-methylene-bis- (4-ethyl-6
tert-butylphenol), 2,2′-methylene-
Bis- (6-cyclohexyl-4-methylphenol), 2,2′-methylene-bis- [6- (1-methylcyclohexyl) -p-cresol], 2,2′-ethylidene-bis- (2,4 -Di-tert-butylphenol), 2,2'-butylidene-bis- (2-tert
-Butyl-4-methylphenol), 4,4'-methylene-bis- (2,6-di-tert-butylphenol), 4,4'-butylidene-bis- (3-methyl-6
-Tert-butylphenol), 4,4'-butylidene-bis- (3-methyl-6-tert-butylphenol), 1,6-hexanediol-bis- [3-
(3,5-di-tert-butyl-4-hydroxyphenyl) -propionate], tri-ethyleneglycol-bis- [3- (3-tert-butyl-5-methyl-
4-hydroxyphenyl) -propionate], N,
N'-bis- [3- (3,5-di-tert-butyl-
4-hydroxyphenyl) -propionyl] -hydrazine, N, N'-bis- [3- (3,5-di-tert-
Butyl-4-hydroxyphenyl) -propionyl]-
Hexamethylenediamine, 2,2'-thio-bis- (4
-Methyl-6-tert-butylphenol), 4,
4'-thio-bis- (3-methyl-6-tert-butylphenol), 2,2'-thio-diethylene-bis-
[3- (3,5-di-tert-butyl-4-hydroxyphenyl) -propionate], bis [2-tert
-Butyl-4-methyl-6- (3-tert-butyl-
5-methyl-2-hydroxybenzyl) -phenyl]-
Terephthalate, 1,1,3-tris- (2-methyl-
4-hydroxy-5-tert-butylphenyl) -butane, 1,3,5-trimethyl-2,4,6-tris-
(3,5-di-tert-butyl-4-hydroxybenzyl) -benzene, tris (3,5-di-tert-butyl-4-hydroxybenzyl) -isocyanurate,
Tris [2- (3,5-di-tert-butyl-4-hydroxyhydro-cinnamyloxy) ethyl] isocyanurate, tris (4-tert-butyl-2,6-di-methyl-3-hydroxybenzyl) -isocyanate Nurate, tetrakis- [methylene-3- (3,5-di-te
rt-butyl-4-hydroxyphenyl) propionate] -methane, calcium bis- [ethyl- (3,5-
Di-tert-butyl-4-hydroxybenzyl) -phosphate], propyl-3,4,5-tri-hydroxybenzenecarbonate, octyl-3,4,5-tri-hydroxybenzenecarbonate, dodecyl-3,
4,5-tri-hydroxybenzene carbonate, 2,
2'-methylene-bis- (4-m-ethyl-6-ter
t-butylphenol), 4,4'-methylene-bis-
(2,6-di-tert-butylphenol), 1,1
-Bis- (4-hydroxy-phenyl) -cyclohexane, 1,1,3-tris- (2-methyl-4-hydroxy-5-tert-butylphenyl) -butane, 1,
3,5-trimethyl-2,4,6-tris- (3,5-
Di-tert-butyl-4-hydroxybenzyl) benzene, 3,9-bis [1,1, -di-methyl-2- [β
-(3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] -2,4.
8,10-tetraoxaspiro [5,5] undecane,
2-pyridyl-2-yl-phenol, 2-pyrimidyl-2-yl-phenol, 2-pyrazyl-2-yl-phenol, 2-pyridyl-2-yl-α-naphthol, 3
-Pyridyl-2-yl-β-naphthol, 2-quinoline-
2-yl-phenol, 2-quinazolin-2-yl-phenol, 2-quinoxalin-2-yl-phenol,
2-quinolin-2-yl-α-naphthol, 3-quinolin-2-yl-β-naphthol, 2-benzoxazole-
2-yl-phenol, 2-benzothiazol-2-yl-phenol, 3-benzoxazol-2-yl-
β-naphthol, 3-benzothiazol-2-yl-β-naphthol, 2-5′-phenyloxadiazole-2-
Yl-phenol, 2-5′-phenylthiodiazol-2-yl-phenol, 2-5′-α-naphthyloxadiazol-2-yl-phenol, 3-5′-phenylthiodiazol-2-yl -Β naphthol, 3-5 '
-Α-naphthyloxadiazol-2-yl-β-naphthol, 2-5′-α-naphthylthiodiazol-2-yl-
Phenol, 2-5'-β naphthyloxadiazole-
2-yl-phenol, 2-5′-βnaphthylthiodiazol-2-yl-phenol, 2-3′-phenylbenzodiazol-2-yl-phenol, 2-3′-α
Naphthylbenzodiazol-2-yl-phenol, 3
-3'-phenylbenzodiazol-2-yl-β naphthol and the like. Preferably, 3,9-bis [1,1, -di-methyl-2- [β- (3-tert-
Butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane.

Among the additives, compounds containing a heterocyclic compound group having a hydroxyl group include 8-quinolinol, 2-methyl-8-quinolinol, 3-methyl-8-quinolinol, 4-methyl-8-quinolinol, Methyl-8-
Quinolinol, 6-methyl-8-quinolinol, 7-methyl-8-quinolinol, 2,4-dimethyl-8-quinolinol, 3,4-dimethyl-8-quinolinol, 4,
5-dimethyl-8-quinolinol, 2,4,5-trimethyl-8-quinolinol, 2-ethyl-8-quinolinol, 3-ethyl-8-quinolinol, 4-ethyl-8-
Quinolinol, 5-ethyl-8-quinolinol, 6-ethyl-8-quinolinol, 7-ethyl-8-quinolinol, 2,4-diethyl-8-quinolinol, 3,4-diethyl-8-quinolinol, 4,5- Diethyl-8-quinolinol, 2,4,5-triethyl-8-quinolinol, 2-phenyl-8-quinolinol, 3-phenyl-
8-quinolinol, 4-phenyl-8-quinolinol,
5-phenyl-8-quinolinol, 6-phenyl-8-
Quinolinol, 7-phenyl-8-quinolinol, 4,
5-diphenyl-8-quinolinol, 4,6-diphenyl-8-quinolinol, 8-hydroxycinnoline, 8
-Hydroxyquinazoline, 8-hydroxyquinoxaline, 4-hydroxyacridine, 4-hydroxyphenanthridine, 4-hydroxyphenazine, 10-hydroxybenzo [h] quinoline, 8-hydroxycarbazole, 5-hydroxychromone, 5-hydroxyflavone and the like Is raised.

These additives may be used alone or as a mixture of two or more. The use amount of these additives is 0.02% by weight or more and 9% by weight or less, preferably 0.2% by weight or more and 5% by weight or less, more preferably 0.5% by weight or more based on the layer containing the compound. It is more preferably at most 4% by weight. When the amount is less than 0.02% by weight, the effect of the present invention is insufficient, and when it exceeds 9% by weight, the characteristics of the organic EL device are impaired.

There is no particular limitation on the method of adding an additive to the organic layer constituting the organic EL element.
Alternatively, a method by film formation from a mixed solution is exemplified. When forming a film from a solution, a polymer binder may be used in combination. When the organic layer is made of a polymer material, a method of forming a film from a mixed solution is exemplified.

The solvent used for film formation from a solution is not particularly limited as long as it can dissolve a low molecular material, a high molecular material, and an additive. As the solvent, chloroform, methylene chloride, chlorine solvents such as dichloroethane, ether solvents such as tetrahydrofuran, aromatic hydrocarbon solvents such as toluene and xylene, acetone, ketone solvents such as methyl ethyl ketone, ethyl acetate, butyl acetate, Ester solvents such as ethylcellose acetate are exemplified.

As a method of forming a film from a solution, microgravure coating from a solution, gravure coating, bar coating, roll coating, wire bar coating, dip coating, spray coating, screen printing,
Flexographic printing, offset printing, inkjet printing, and the like can be given. As the polymer binder, those which do not extremely impair the charge transporting performance and the light emitting performance are preferable, and those which do not strongly absorb visible light are suitably used. Examples of the polymer binder include polycarbonate, polyacrylate, polymethyl acrylate, polymethyl methacrylate, polystyrene, polyvinyl chloride, and polysiloxane.

In the organic EL device of the present invention, lithium or lithium is used as the alkali metal used in the layer adjacent to the layer containing the additive and containing the alkali metal, the alloy containing the alkali metal, or the compound containing the alkali metal. Sodium, potassium, rubidium, cesium,
Lithium is preferred. Examples of the alloy containing an alkali metal include two or more alloys of lithium, sodium, potassium, rubidium, and cesium, or one of them.
One or more, beryllium, magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium, ytterbium, gold, silver, platinum, copper, manganese, titanium, cobalt, An alloy with one or more of nickel, tungsten, and tin is given.

Examples of alloys include lithium-silver alloy, lithium-indium alloy, lithium-magnesium alloy, lithium-aluminum alloy, lithium-calcium alloy, lithium-ytterbium alloy, lithium-zinc alloy, potassium-sodium alloy, rubidium -Silver alloy, rubidium-indium alloy, rubidium-magnesium alloy, rubidium-aluminum alloy, rubidium-calcium alloy, rubidium-ytterbium alloy, rubidium-zinc alloy, cesium-silver alloy, cesium-indium alloy, cesium-magnesium alloy, cesium -Aluminum alloy, cesium-calcium alloy, cesium-ytterbium alloy, cesium-zinc alloy and the like. Preferably, lithium-aluminum alloy, sodium-aluminum alloy, potassium-
Aluminum alloy, rubidium-aluminum alloy, and cesium-aluminum alloy.

Examples of the compound containing an alkali metal include halides such as an oxide of an alkali metal, a sulfide of an alkali metal, a fluoride and a chloride of an alkali metal, a salt containing an alkali metal, a complex containing an alkali metal, Inclusion compounds such as crown ethers containing alkali metals. Specifically, as an alkali metal oxide,
Lithium oxide, lithium peroxide, lithium aluminate,
Lithium metaborate, lithium tetraborate, lithium germanate, lithium molybdate, lithium niobate, lithium metasilicate, lithium tantalate, lithium titanate, lithium vanadate, lithium tungstate, lithium zirconate, sodium oxide, sodium peroxide , Sodium aluminate, sodium tetraborate, sodium metaborate, sodium tetraborate, sodium bismuthate, sodium germanate, sodium molybdate, sodium niobate, sodium metasilicate, sodium tantalate, sodium titanate, sodium vanadate, tungsten Sodium silicate, sodium zirconate, potassium oxide, potassium aluminate, potassium germanate, potassium molybdate, potassium niobate, potassium silicate, Potassium tantalum, potassium titanate, potassium vanadate, potassium tungstate,
Examples include potassium zirconate, rubidium oxide, rubidium peroxide, rubidium chromate, cesium oxide, and cesium chromate.

The alkali metal halides include lithium fluoride, lithium chloride, lithium bromide, lithium iodide, sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, and bromide. Examples include potassium, potassium iodide, rubidium fluoride, rubidium chloride, rubidium bromide, rubidium iodide, cesium fluoride, cesium chloride, cesium bromide, cesium iodide, and the like. Preferred are lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, and cesium fluoride.

Examples of the alkali metal salts include lithium carbonate, lithium oxalate, lithium nitrate, lithium phosphate, lithium sulfate, lithium nitride, lithium sulfide, sodium carbonate, sodium oxalate, sodium nitrate, sodium phosphate, sodium sulfate, and the like. Examples include sodium sulfide, potassium carbonate, potassium oxalate, potassium nitrate, potassium phosphate, potassium sulfate, potassium sulfide, rubidium carbonate, rubidium nitrate, rubidium sulfate, cesium carbonate, cesium nitrate, and cesium sulfate.

Examples of the complex containing an alkali metal include an acetylacetonate complex, an acetylacetone complex, a quinoline complex, a pyridine complex, an ethylenediamine complex, a phenanthroline complex, a porphyrin complex, and a phthalocyanine complex containing an alkali metal. Is raised. 18-crown-6, dibenzo-14-crown-4, dibenzo-18-crown-6, dibenzo-24-crown-8, dibenzo-30-crown containing an alkali metal as an inclusion compound containing an alkali metal -1
0, cyclohexyl-18-crown-6, cyclodextrin, cyclophan, azacyclophan and the like. Among compounds containing an alkali metal, preferred are halides such as lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, and cesium fluoride, and acetylacetonate-based complexes containing an alkali metal.

An alkali metal, an alloy containing an alkali metal,
Alternatively, as a method for forming a layer containing a compound containing an alkali metal, a vacuum evaporation method, a sputtering method, or the like is used. When the compound containing an alkali metal is soluble in an organic solvent or the like, coating from a solution in which the compound is dissolved in an organic solvent, or coating from a mixed solution in which the compound and a polymer compound are dissolved in an organic solvent Can be used.

Alkali metals, alloys containing alkali metals,
Alternatively, the film thickness of the layer containing the compound containing an alkali metal may have an optimum value which varies depending on the material used, and may be selected so as to obtain good characteristics of the organic EL element. For example, the thickness is 0.1 nm to 100 nm, Preferably 0.
2 nm to 50 nm, more preferably 0.5 nm
５5 nm.

Next, the members used for the organic EL device of the present invention will be described. As the light emitting material contained in the light emitting layer of the organic EL device in the present invention, a known material can be used. Examples of the low molecular weight compound include naphthalene or a derivative thereof, anthracene or a derivative thereof, perylene or a derivative thereof, polymethine-based, xanthene-based, coumarin-based, and cyanine-based dyes, 8-hydroxyquinoline or a metal complex of a derivative thereof, and an aromatic compound. Group amine,
For example, tetraphenylcyclopentadiene or a derivative thereof, or tetraphenylbutadiene or a derivative thereof can be used. Specifically, known materials such as those described in JP-A-57-51781 and JP-A-59-194393 can be used. Further, as the light emitting material used in the light emitting layer of the organic EL element in the present invention, a polymeric fluorescent substance is preferable. A polymeric fluorescent substance having a molecular weight of ³ to 1 × 10 ⁸ is preferably used, has fluorescence in a solid state, and has a number average molecular weight of 1 × 10 ³ to 1 in terms of polystyrene.
× 10 ⁸ , and a polymeric fluorescent substance containing at least one kind of a repeating unit represented by the following formula (2) is more preferable.

Embedded image -Ar _2- (CR ₂ = CR ₃ ) _k- (2) wherein Ar ₂ is a divalent group forming a carbon-carbon bond with two adjacent groups. An arylene group having 6 to 60 carbon atoms participating in conjugation, or 4 to 60 carbon atoms participating in conjugation.
Or less, and the arylene group and the heterocyclic compound group may have a substituent. R ₂ and R ₃ each independently represent a hydrogen atom,
A group selected from the group consisting of a linear, branched or cyclic alkyl group of 20, an aryl group having 6 to 60 carbon atoms, a heterocyclic compound group having 4 to 60 carbon atoms, and a cyano group; The ring compound group may have a substituent. k is 0 or 1. In the organic EL device of the present invention, two or more kinds of light-emitting layers, for example, a polymer phosphor,
A light emitting material composed of a low molecular compound may be used as a mixture. A light-emitting layer containing a light-emitting material other than the polymeric fluorescent substance,
It may be laminated with the light emitting layer containing the polymer fluorescent substance.

Further, the polymeric fluorescent substance used in the present invention has fluorescence in a solid state, has a polystyrene equivalent number average molecular weight of 1 × 10 ³ to 1 × 10 ⁸ , and has the following formula (3): It is still more preferable that it contains at least one kind of the repeating units represented by the following formulas (4) and (5), and particularly preferable that the repeating units are represented by the formulas (3), (4) and (5) Respectively at least one kind.

Embedded image [Here, Ar ₃ is a divalent group that forms a carbon-carbon bond with each of two adjacent groups, and an arylene group in which the number of carbon atoms involved in conjugation is 6 or more and 60 or less, or The number of carbon atoms involved in conjugation is 4 or more and 60
And a heterocyclic compound group consisting of not more than Ar
₃ is a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms other than -XR ₄ , an alkoxy group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, An alkylthio group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a monoalkylsilyl group, a dialkylsilyl group or a trialkylsilyl group having 1 to 60 carbon atoms (hereinafter referred to as mono, di or trialkyl A silyl group), a monoalkylamino group or a dialkylamino group having 1 to 40 carbon atoms (hereinafter sometimes referred to as a mono or dialkylamino group), an aryl group having 6 to 60 carbon atoms, and a 6 to 60 carbon atoms. Aryloxy group having 7 to 7 carbon atoms
Having a substituent selected from the group consisting of an arylalkyl group having 60, an arylalkoxy group having 7 to 60 carbon atoms, an arylamino group having 6 to 60 carbon atoms, a heterocyclic compound group having 4 to 60 carbon atoms, and a cyano group. And the aryl group, aryloxy group, arylalkyl group, arylalkoxy group, arylamino group, and heterocyclic compound group may further have a substituent. Where linear,
An alkylthio group having a branched or cyclic alkyl group means that the alkyl group constituting the alkylthio group is a straight-chain,
It means a branched or cyclic alkyl group (the same applies hereinafter). When Ar ₃ has a plurality of substituents, they may be the same or different. R ₄ is a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a mono-, di- or trialkylsilyl group having 1 to 60 carbon atoms, an aryl group having 6 to 60 carbon atoms, 60 arylalkyl groups and 4 to 6 carbon atoms
0 represents a group selected from the group consisting of a heterocyclic compound group,
The aryl group, the arylalkyl group and the heterocyclic compound group may have a substituent. Further, the carbon atom of the group represented by —X—R _{4 and} the substituent other than —X—R ₄ that Ar ₃ has may be replaced by an oxygen atom or a sulfur atom, if possible. ₃ has -X-
At least one hydrogen atom of the group and -X-R ₄ substituent other than represented by R ₄ may be replaced by fluorine atoms. o is an integer of 1 to 4. X is -O-, -S-,-
_{CR 7 R 8 -, - SiR} 9 R 10 -, - NR 11 -, - CO
-, - COO -, - SO 2 -, - CR 12 = CR 13 -, and represents a group selected from the group consisting of -C≡C-. o is
It is an integer of 1 to 4. R ₅ , R ₆ and R _{7 to} R ₁₃ each independently represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 60 carbon atoms, 60 represents a group selected from the group consisting of a heterocyclic compound group and a cyano group, and the aryl group and the heterocyclic compound group may have a substituent. p is 0 or 1. ]

[0039]

Embedded image [Here, Ar ₄ is a divalent group that forms a carbon-carbon bond with each of two adjacent groups, and an arylene group in which the number of carbon atoms involved in conjugation is 6 or more and 60 or less, or The number of carbon atoms involved in conjugation is 4 or more and 60
And a heterocyclic compound group consisting of not more than Here, Ar ₄ has a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms other than -Ar _5. Alkoxy group, alkylthio group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, mono-, di- or trialkylsilyl group having 1 to 60 carbon atoms, mono- or dialkylamino having 1 to 40 carbon atoms Group, an aryl group having 6 to 60 carbon atoms, an aryloxy group having 6 to 60 carbon atoms, and 7 carbon atoms
An arylalkyl group having from 60 to 60, an arylalkoxy group having from 7 to 60 carbon atoms, an arylamino group having from 6 to 60 carbon atoms,
It may have a substituent selected from the group consisting of a heterocyclic compound group having 4 to 60 carbon atoms and a cyano group, and may have an aryl group, an aryloxy group, an arylalkyl group, an arylalkoxy group, an arylamino group, and a heterocyclic group. The compound group may further have a substituent. When Ar ₄ has a plurality of substituents, they may be the same or different. Ar ₅ has 6 to 60 carbon atoms.
An aryl group or a heterocyclic compound group having 4 to 60 carbon atoms, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms. An alkoxy group having an alkyl group, an alkylthio group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a mono-, di- or trialkylsilyl group having 1 to 60 carbon atoms, Mono- or dialkylamino group, aryl group having 6 to 60 carbon atoms, aryloxy group having 6 to 60 carbon atoms, arylalkyl group having 7 to 60 carbon atoms, arylalkoxy group having 7 to 60 carbon atoms, 6 carbon atoms
A substituent selected from the group consisting of an arylalkenyl group having from 60 to 60, an arylalkynyl group having from 6 to 60 carbon atoms, an arylamino group having from 6 to 60 carbon atoms, a heterocyclic compound group having from 4 to 60 carbon atoms, and a cyano group. The aryl group, the aryloxy group, the arylalkyl group, the arylalkoxy group, the arylamino group, and the heterocyclic compound group may further have a substituent. In addition, Ar ₄
Carbon atom of the group and -Ar ₅ other substituents represented by -Ar ₅ which has, if possible, may be replaced with an oxygen atom or a sulfur atom, Ar ₄ has - One or more hydrogen atoms of the group represented by Ar ₅ and a substituent other than -Ar ₅ may be replaced by a fluorine atom. q is an integer of 1 to 4. R ₁₄ and R ₁₅ are each independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 60 carbon atoms, or a heterocyclic compound group having 4 to 60 carbon atoms. And a group selected from the group consisting of a cyano group, and the aryl group and the heterocyclic compound group may have a substituent. r is 0 or 1. ]

[0040]

Embedded image [Here, Ar ₆ is a divalent group that forms a carbon-carbon bond with each of two adjacent groups, and an arylene group in which the number of carbon atoms involved in conjugation is 6 or more and 60 or less, or The number of carbon atoms involved in conjugation is 4 or more and 60
And a heterocyclic compound group consisting of not more than Here, Ar ₆ has a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms other than -R _16. Alkoxy group, alkylthio group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, mono-, di- or trialkylsilyl group having 1 to 60 carbon atoms, mono- or dialkylamino having 1 to 40 carbon atoms Group, an aryl group having 6 to 60 carbon atoms, an aryloxy group having 6 to 60 carbon atoms, and 7 carbon atoms
An arylalkyl group having from 60 to 60, an arylalkoxy group having from 7 to 60 carbon atoms, an arylamino group having from 6 to 60 carbon atoms,
It may have a substituent selected from the group consisting of a heterocyclic compound group having 4 to 60 carbon atoms and a cyano group, and may have an aryl group, an aryloxy group, an arylalkyl group, an arylalkoxy group, an arylamino group, and a heterocyclic group. The compound group may further have a substituent. When Ar ₆ has a plurality of substituents, they may be the same or different. R ₁₆ is a linear, mono-, di- or trialkylsilyl group having 1 to 60 carbon atoms, a mono- or dialkylamino group having 1 to 40 carbon atoms, a branched or cyclic alkyl group, Number 4-60
And a group selected from the group consisting of a saturated heterocyclic compound group and an arylalkyl group having 7 to 60 carbon atoms, and the arylalkyl group may have a substituent. In addition, Ar ₆
Carbon atom of the group and -R ₁₆ substituent other than represented by in which -R ₁₆ which has, if possible oxygen atom may be replaced with a sulfur atom, Ar ₆ has - R ₁₆
In one or more of the hydrogen atoms of the group and -R ₁₆ substituent other than shown it may be replaced by fluorine atoms. s is
It is an integer of 1 to 4. R ₁₇ and R ₁₈ each independently represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 60 carbon atoms,
And 60 represents a group selected from the group consisting of a heterocyclic compound group and a cyano group, and the aryl group and the heterocyclic compound group may have a substituent. t is 0 or 1. ]

Among them, the total of the repeating units represented by the formulas (3), (4) and (5) is preferably at least 50 mol% of all the repeating units, and the formulas (3) and (4) And 0.1 to 30 mol% of the repeating unit of the formula (3) and 30 mol% of the repeating unit of the formula (4) based on the total of the repeating units of the formula (5). The polymer fluorescent substance has a repeating unit represented by the formula (5) of 30 mol% or more and 70 mol% or less. Most preferably, the repeating unit represented by the formula (3) is at least 0.2 mol% and at most 10 mol% based on the total number of repeating units.

Ar ₂ , Ar ₃ , Ar ₄ and Ar ₆ may be selected so as not to impair the fluorescent properties of the polymeric fluorescent substance. And divalent groups.

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Here, in the case of Ar ₃ , R is -X-
It is selected so as to have 1 to 4 substituents represented by R ₄ , and in the case of Ar ₄ , the substituent represented by -Ar ₅ is 1 to 4
Four, and in the case of Ar ₆ ,
Selected substituents represented by R ₁₆ to have 1-4. The remaining R is a hydrogen atom, a linear C 1-20,
A branched or cyclic alkyl group, a linear or branched or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group having a linear or branched or cyclic alkyl group having 1 to 20 carbon atoms, Group, C 1-60 mono,
Di- or trialkylsilyl group, mono- or di-alkylamino group having 1 to 40 carbon atoms, aryl group having 6 to 60 carbon atoms, aryloxy group having 6 to 60 carbon atoms, 7 to 6 carbon atoms
An arylalkyl group having 0, an arylalkoxy group having 7 to 60 carbon atoms, an arylalkenyl group having 8 to 60 carbon atoms,
Arylalkynyl group having 8 to 60 carbon atoms, 6 to 6 carbon atoms
0 represents a substituent selected from the group consisting of a monoarylamino group or a diarylamino group (hereinafter sometimes referred to as a mono or diarylamino group), a heterocyclic compound group having 2 to 60 carbon atoms, and a cyano group, The aryloxy group, the arylalkyl group, the arylalkoxy group, the arylalkenyl group, the arylalkynyl group, the mono- or diarylamino group and the heterocyclic compound group may further have a substituent.

In the above example, one structural formula has a plurality of Rs, but they may be the same,
The groups may be different and are each independently selected.
Further, the carbon atom of the substituent of Ar ₂ , Ar ₃ , Ar ₄ and Ar ₆ may be replaced with an oxygen atom or a sulfur atom, or the substituent of Ar ₂ , Ar ₃ , Ar ₄ and Ar ₆ One or more hydrogen atoms may be replaced by a fluorine atom.

In order to enhance the solubility in a solvent, it is preferable that the compound has at least one substituent that is not a hydrogen atom, and that the repeating unit including the substituent has a low symmetry. .

[0046] X is -O -, - S -, - CR 7 R 8 -, - S
_{iR 9 R 10 -, - NR} 11 -, - CO -, - COO -, -
A group selected from the group consisting of SO ₂ —, —CR ₁₂ ＣＲCR ₁₃ —, and —C≡C—, but —O—, —S—, and —C
R ₁₂ ＣＲCR ₁₃ — and —C≡C— are preferred, and —O—
Is more preferred. R ₇ to R ₁₃ each independently represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 60 carbon atoms,
And 60 represents a group selected from the group consisting of a heterocyclic compound group and a cyano group, and the aryl group and the heterocyclic compound group may further have a substituent.

As a specific example of R ₄ and R ₁₆ , carbon atoms of 1
Examples of the linear, branched or cyclic alkyl group of -20 include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an iso-butyl group and a tert.
-Butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, lauryl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclo A dodecyl group and the like are exemplified, and a pentyl group, a hexyl group, an octyl group, a decyl group, and a cyclohexyl group are preferred.

Examples of the alkoxy group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, an n-propyloxy group, an iso-propyloxy group, an n-butoxy group, an iso-butoxy group,
tert-butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, nonyloxy group, decyloxy group, lauryloxy group, cyclopropyloxy group, cyclobutyloxy group, cyclopentyloxy group, cyclohexyloxy group, cyclo A heptyloxy group and the like are exemplified, and a pentyloxy group, a hexyloxy group, an octyloxy group, a decyloxy group, and a cyclohexyloxy group are preferable.

Examples of the alkylthio group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms include a methylthio group, an ethylthio group, an n-propylthio group and an iso-
Propylthio, n-butylthio, iso-butylthio, tert-butylthio, pentylthio, hexylthio, heptylthio, octylthio, nonylthio, decylthio, laurylthio, cyclopropylthio, cyclobutylthio, cyclopentyl Examples thereof include a thio group, a cyclohexylthio group, and a cycloheptylthio group, and a pentylthio group, a hexylthio group, an octylthio group, a decylthio group, and a cyclohexylthio group are preferable.

The mono-, di- or trialkylsilyl group having 1 to 60 carbon atoms includes monomethylsilyl group, dimethylsilyl group, trimethylsilyl group, monoethylsilyl group,
Diethylsilyl group, triethylsilyl group, monopropylsilyl group, dipropylsilyl group, tripropylsilyl group, monobutylsilyl group, dibutylsilyl group, tributylsilyl group, monopentylsilyl group, dipentylsilyl group, tripentylsilyl group, Monohexylsilyl group, dihexylsilyl group, trihexylsilyl group, monoheptylsilyl group, diheptylsilyl group, triheptylsilyl group, monooctylsilyl group, dioctylsilyl group, monooctylsilyl group, dioctylsilyl group, trioctylsilyl Group, monononylsilyl group, dinonylsilyl group, trinonylsilyl group, monodecylsilyl group, didecylsilyl group, tridecylsilyl group, monolaurylsilyl group, dilaurylsilyl group, trilaurylsilyl group, ethyldimethylsilyl group, Dimethylsilyl group, butyldimethylsilyl group, pentyldimethylsilyl group, hexyldimethylsilyl group, heptyldimethylsilyl group, octyldimethylsilyl group, nonyldimethylsilyl group, decyldimethylsilyl group, lauryldimethylsilyl group, and the like. Pentylsilyl group, trihexylsilyl group,
Trioctylsilyl, tridecylsilyl, pentyldimethylsilyl, hexyldimethylsilyl, octyldimethylsilyl, and decyldimethylsilyl are preferred.

The mono- or di-alkylamino group having 1 to 40 carbon atoms includes monomethylamino group, dimethylamino group, monoethylamino group, diethylamino group, monopropylamino group, dipropylamino group, monobutylamino group, dibutylamino group. Group, monopentylamino group, dipentylamino group, monohexylamino group, dihexylamino group, monoheptylamino group, diheptylamino group, monooctylamino group, dioctylamino group, monononylamino group, dinonylamino group, monodecylamino And a didecylamino group, a monolaurylamino group, a dilaurylamino group, and the like. It is preferred.

An arylalkoxy group having 7 to 60 carbon atoms and
Is phenyl-C₁~ C₁₂Alkoxy group, C₁~ C₁₂
Alkoxyphenyl-C₁~ C₁₂Alkoxy group, C₁~ C
₁₂Alkylphenyl-C₁~ C₁₂Alkoxy group, 1-na
Futyl-C₁~ C₁₂Alkoxy group, 2-naphthyl-C₁~
C₁₂And an alkenyl group such as phenyl-C.₁~ C
₁₂Alkoxy group, C₁~ C₁₂Alkoxyphenyl-C₁~
C₁₂Alkoxy group, C ₁~ C₁₂Alkylphenyl-C₁~
C₁₂Alkoxy groups are preferred. Ally with 6 to 60 carbon atoms
Phenyl, naphthyl, anthryl
Group, pyrenyl group, perylenyl group and the like;₁~
C₁₂Alkyl group, C₁~ C₁₂Alkoxy group, C₆~ C₂₀A
A reel group as a substituent;₁
~ C₁₂A phenyl group having an alkoxy group, C₁~ C₁₂A
A phenyl group having an alkyl group is preferred.

Examples of the aryloxy group having 6 to 60 carbon atoms include a phenoxy group, a naphthyloxy group, an anthryloxy group and the like, and include a C ₁ -C ₁₂ alkyl group, a C ₁ -C ₁₂
It may further have an alkoxy group or a C ₆ -C ₂₀ aryl group as a substituent, and is preferably a phenoxy group having a C ₁ -C ₁₂ alkoxy group or a phenoxy group having a C ₁ -C ₁₂ alkyl group.

The arylalkyl group having 7 to 60 carbon atoms includes a phenyl-C ₁ -C ₁₂ alkyl group and a naphthyl-C ₁
-C ₁₂ alkyl group, anthryl -C ₁ -C ₁₂ alkyl groups and the like, having C ₁ -C ₁₂ alkyl group, C ₁ -C ₁₂ alkoxy group, as a substituent a C ₆ -C ₂₀ aryl group even if well, C ₁ -C ₁₂ phenyl -C ₁ -C ₁₂ alkyl group having an alkoxy group, a phenyl -C ₁ -C ₁₂ alkyl group having a C ₁ -C ₁₂ alkyl group.

Examples of the arylalkoxy group having 7 to 60 carbon atoms include a phenyl-C ₁ -C ₁₂ alkoxy group, a naphthyl-C ₁ -C ₁₂ alkoxy group and an anthryl-C ₁ -C ₁₂ alkoxy group. ₁ -C ₁₂ alkyl group, C ₁ ~
C ₁₂ alkoxy group may have as a substituent a C ₆ -C _{2 0} aryl group, a phenyl -C ₁ -C ₁₂ alkoxy group having C ₁ -C ₁₂ alkoxy group, C ₁ -C ₁₂ alkyl preferably phenyl -C ₁ -C ₁₂ alkoxy group having a group.

Examples of the arylalkenyl group having 8 to 60 carbon atoms include a phenylethenyl group, a naphthylethenyl group, an anthrylethenyl group, a pyrenylethenyl group and the like, and include a C ₁ -C ₁₂ alkyl group and a C ₁ -C ₁₂ alkoxy group. Group, C
₆ -C ₂₀ aryl group may have as a substituent a, phenylethenyl group having phenylethenyl group, phenylethenyl group having C ₁ -C ₁₂ alkoxy group, a C ₁ -C ₁₂ alkyl group Is preferred.

[0057] As an arylalkynyl group having 8 to 60 carbon atoms, a phenyl ethynyl group, naphthylethynyl group, anthryl ethynyl group, a pyrenylethynyl group and the like, C ₁ -C ₁₂ alkyl group, C ₁ -C ₁₂ alkoxy group , C
₆ -C ₂₀ aryl group may have as a substituent a phenyl ethynyl group, phenylethynyl group having C ₁ -C ₁₂ alkoxy group, phenylethynyl group having C ₁ -C ₁₂ alkyl group.

The mono- or di-arylamino group having 6 to 60 carbon atoms includes a monophenylamino group, a C ₁ -C ₁₂ alkyl-phenylamino group, a diphenylamino group, a mononaphthylamino group and a C ₁ -C ₁₂ alkyl-naphthyl. amino group, dinaphthylamino group, a phenyl naphthyl amino group and the like, C ₁ -C ₁₂ alkyl group, C ₁ -C ₁₂ alkoxy group, which may have as a substituent a C ₆ -C ₂₀ aryl group Of these, a C ₁ -C ₁₂ alkylphenylamino group and a di (C ₁ -C ₁₂ alkylphenyl) amino group are preferred. .

As a heterocyclic compound group having 2 to 60 carbon atoms
Represents a pyrrolyl group, a pyridyl group, a piperazyl group, a quinolyl
Group, quinoxalyl group, indolyl group, carbazoyl group,
Furyl, benzofuryl, dibenzofuryl, thienyl
Group, benzothienyl group, dibenzothienyl group, oxa
Diazolyl, oxazolyl, triazolyl, thio
Diazolyl group, benzoxazolyl group, benzodiazolyl group
And a benzosilolyl group.
C₁~ C₁₂Alkyl group, C₁~ C₁₂Alkoxy group, C₆~
C₂₀The aryl group may further have a substituent.
Thienyl group, C₁ ~ C₁₂Thieni with alkyl group
Group, pyridyl group, C₁~ C₁₂Pyri with alkyl group
A jyl group is preferred.

Among the examples of the substituents of Ar ₂ , Ar ₃ , Ar ₄ and Ar ₆ , in the substituent containing an alkyl chain, they may be linear, branched or cyclic, or a combination thereof. When it is not linear, examples thereof include an isoamyl group, a 2-ethylhexyl group, a 3,7-dimethyloctyl group, a cyclohexyl group, and a 4-C ₁ -C ₁₂ alkylcyclohexyl group. In order to increase the solubility of the polymeric fluorescent substance in the solvent, Ar ₂ , Ar ₃ , Ar
Preferably, at least one of the substituents of ₄ and Ar ₆ contains a cyclic or branched alkyl chain. Also,
The ends of two alkyl chains may be linked to form a ring. Further, some carbon atoms of the alkyl chain may be replaced by a group containing a hetero atom, and examples of the hetero atom include an oxygen atom, a sulfur atom, and a nitrogen atom.

Further, Ar ₂ , Ar ₃ , Ar ₄ and Ar ₆
When the aryl group or the heterocyclic compound group is included in a part of the examples of the substituents described above, they may further have one or more substituents.

R ₂ , R ₃ , R _{5 to} R ₁₅ , R ₁₇ and R
_{When 18} is a substituent other than a hydrogen atom or a cyano group, as a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a methyl group, an ethyl group,
n-propyl group, iso-propyl group, n-butyl group,
iso-butyl group, tert-butyl group, pentyl group,
Hexyl group, heptyl group, octyl group, nonyl group, decyl group, lauryl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclododecyl group, and the like, Pentyl, hexyl, octyl, decyl and cyclohexyl are preferred.

The aryl group having 6 to 60 carbon atoms includes
Phenyl, naphthyl, anthryl, pyrenyl,
Renyl group and the like are exemplified;₁~ C₁₂Alkyl group, C₁
~ C ₁₂Alkoxy group, C₆~ C₂₀Aryl group
A phenyl group, a C₁~ C₁₂
A phenyl group having an alkyl group is preferred.

As a heterocyclic compound group having 2 to 60 carbon atoms
Represents a pyrrolyl group, a pyridyl group, a piperazyl group, a quinolyl
Group, quinoxalyl group, indolyl group, carbazoyl group,
Furyl, benzofuryl, dibenzofuryl, thienyl
Group, benzothienyl group, dibenzothienyl group, oxa
Diazolyl, oxazolyl, triazolyl, thio
Diazolyl group, benzoxazolyl group, benzodiazolyl group
And a benzosilolyl group.
C₁~ C₁₂Alkyl group, C₁~ C₁₂Alkoxy group, C₆~
C₂₀The aryl group may further have a substituent.
Thienyl group, C₁ ~ C₁₂Thieni with alkyl group
Group, pyridyl group, C₁~ C₁₂Pyri with alkyl group
A jyl group is preferred.

The terminal group of the polymeric fluorescent substance is protected by a stable group, since if the polymerization active group is left as it is, the light emission characteristics and life of the device may be reduced. Is also good. Those having a conjugate bond continuous with the conjugate structure of the main chain are preferable, and examples thereof include a structure in which the conjugate structure is bonded to an aryl group or a heterocyclic compound group via a vinylene group. Specifically, substituents described in Chemical Formula 10 of JP-A-9-45478 are exemplified.

As a method for synthesizing the phosphor, when a main chain has a vinylene group, for example, Japanese Patent Application Laid-Open No. 5-202355
The method described in Japanese Unexamined Patent Publication (Kokai) No. H10-26095 can be mentioned. That is, polymerization of a dialdehyde compound and a diphosphonium salt compound or Horner of a dialdehyde compound and a diphosphate compound
Polymerization by a Wittig reaction such as polymerization by the Wadsworth-Emmons method, polymerization by a Heck reaction of a divinyl compound and a dihalogen compound or a vinyl halide compound alone, and polymerization of a compound having two methyl halide groups by a dehalogenation method. Examples of the method include condensation, polycondensation of a compound having two sulfonium bases by a sulfonium salt decomposition method, and polymerization of a dialdehyde compound and a diacetonitrile compound by a Knoevenagel reaction. Of these, JP-A-3-24
Polymerization by a Wittig reaction, polycondensation by a dehydrohalogenation method, and polycondensation by a sulfonium salt decomposition method disclosed in US Pat.

When there is no vinylene group in the main chain, for example, a method of polymerizing the corresponding monomer by a Suzuki coupling reaction, a method of polymerizing by a Grignard reaction, a method of polymerizing by a Ni (0) catalyst, FeCl ₃ And the like, a method of electrochemically oxidizing and polymerizing, a method of decomposing an intermediate polymer having an appropriate leaving group, and the like.

The polymeric fluorescent substance contains a repeating unit other than the repeating unit represented by the formula (1), (2) or (3) as long as the fluorescent property and the charge transport property are not impaired. May be. Further, the repeating unit represented by the formula (1), the formula (2) or the formula (3) or another repeating unit may be linked as a non-conjugated unit, or the repeating unit may have a non-conjugated portion. May be included. Examples of the bonding structure include a compound represented by the following formula (25), a combination of a compound represented by the following formula (25) and a vinylene group, and a combination of two or more compounds represented by the following formula (25). Here, R is a group selected from the same substituents as described above, and Ar represents a hydrocarbon group having 6 to 60 carbon atoms.

Embedded image

The polymeric fluorescent substance may be a random, block or graft copolymer, or a polymer having an intermediate structure between them, for example, a random copolymer having a block property. You may. From the viewpoint of obtaining a polymeric fluorescent substance having a high quantum yield of fluorescence, a random copolymer having block properties or a block or graft copolymer is preferable to a complete random copolymer. The case where the main chain is branched and there are three or more terminal portions, and dendrimers are also included.

Since light emission from a thin film is used, a polymer fluorescent substance having fluorescence in a solid state is preferably used. Examples of good solvents for the polymeric fluorescent substance include chloroform, methylene chloride, dichloroethane, tetrahydrofuran, toluene, xylene, mesitylene, tetralin, decalin, and n-butylbenzene. Although it depends on the structure and molecular weight of the polymeric fluorescent substance, it can be usually dissolved in these solvents in an amount of 0.1% by weight or more.

The polymeric fluorescent substance has a number average molecular weight of 1 × 10 ³ to 1 × 10 ⁸ in terms of polystyrene, and the degree of polymerization thereof varies depending on the repeating structure and its ratio. In general, the total number of repeating structures is preferably from 20 to 10,000, more preferably from 30 to 100, from the viewpoint of film forming properties.
00, particularly preferably 50-5000.

The optimum value of the thickness of the light emitting layer varies depending on the material used, and may be selected so that the driving voltage and the luminous efficiency have appropriate values. For example, the thickness is 1 nm to 1 μm, preferably 2 nm to 500 nm. And more preferably 5 nm to 200 nm.

When these polymer fluorescent materials are used as a light emitting material of an organic EL device, the purity affects the light emitting characteristics. Is preferably polymerized to
After the synthesis, it is preferable to carry out a purification treatment such as reprecipitation purification or fractionation by chromatography.

In the present invention, the organic EL element provided with a charge injection layer (electron injection layer, hole injection layer) includes an organic EL element provided with a charge injection layer adjacent to a cathode, and an electric charge adjacent to an anode. An organic EL device provided with an injection layer is exemplified.
Specific examples of the charge injection layer used include a layer containing a conductive polymer, provided between an anode and a hole transport layer, and a hole transport material contained in the anode material and the hole transport layer. A layer containing a material having an ionization potential of an intermediate value between the cathode material and the electron transport layer, and a material having an electron affinity of an intermediate value between the cathode material and the electron transport material contained in the electron transport layer. And the like.

When the charge injection layer is a layer containing a conductive polymer, the conductive polymer has an electric conductivity of 10 ⁻⁵ S / cm.
Or 10 ³ is preferably S / cm or less, and for decreasing leak current between light emitting pixels, 10 ^-5 S / c
m or more and 10 ² S / cm or less, more preferably 10 ⁻⁵ S / cm.
cm or more and 10 ¹ S / cm or less is more preferable. Usually, the electric conductivity of the conductive polymer is 10 ^-5 S / cm or more and 10
^The conductive polymer is doped with an appropriate amount of ions in order to make it ³ S / cm or less.

The type of ions to be doped is an anion for a hole injection layer and a cation for an electron injection layer.
Examples of anions include polystyrenesulfonate, alkylbenzenesulfonate, camphorsulfonate, and the like, and examples of cations include lithium, sodium, potassium, and tetrabutylammonium. The thickness of the charge injection layer is, for example, 1 nm to 100 nm, and preferably 2 nm to 50 nm.

The material used for the charge injection layer may be appropriately selected depending on the materials of the electrodes and the adjacent layers. Polyaniline and its derivatives, polythiophene and its derivatives, polypyrrole and its derivatives, polyphenylenevinylene and its derivatives, Thienylene vinylene and its derivatives, polyquinoline and its derivatives, polyquinoxaline and its derivatives, conductive polymers such as polymers having an aromatic amine structure in the main chain or side chain, metal phthalocyanine (copper phthalocyanine, etc.), carbon, etc. Illustrated.

The insulating layer having a thickness of 2 nm or less has a function of facilitating charge injection. Examples of the material for the insulating layer include metal fluorides, metal oxides, and organic insulating materials. As the organic EL element provided with an insulating layer having a thickness of 2 nm or less, an organic EL element provided with an insulating layer having a thickness of 2 nm or less adjacent to a cathode and an insulating layer having a thickness of 2 nm or less adjacent to an anode were provided. An organic EL element is mentioned.

When the organic EL device of the present invention has a hole transporting layer, the hole transporting material used includes polyvinyl carbazole or a derivative thereof, polysilane or a derivative thereof, and an aromatic amine in a side chain or a main chain. Polysiloxane derivative, pyrazoline derivative, arylamine derivative, stilbene derivative, triphenyldiamine derivative, polyaniline or its derivative, polythiophene or its derivative, polypyrrole or its derivative, poly (p-phenylenevinylene) or its derivative, or poly (2, 5-thienylenevinylene) or a derivative thereof.

Specifically, examples of the hole transport material include JP-A-63-70257, JP-A-63-175860, JP-A-2-135359, and JP-A-2-13536.
No. 1, No. 2-209988, No. 3-3799
No. 2, JP-A-3-152184, etc. are exemplified.

Among these, as a hole transporting material used for the hole transporting layer, polyvinyl carbazole or a derivative thereof, polysilane or a derivative thereof, a polysiloxane derivative having an aromatic amine compound group in a side chain or a main chain, polyaniline or a polyaniline Derivatives thereof, polythiophene or derivatives thereof, poly (p-phenylenevinylene)
Or a derivative thereof, or a polymer hole transporting material such as poly (2,5-thienylenevinylene) or a derivative thereof, and more preferably polyvinyl carbazole or a derivative thereof, polysilane or a derivative thereof,
A polysiloxane derivative having an aromatic amine in the side chain or main chain. In the case of a low-molecular-weight hole transport material, it is preferable to use the material by dispersing it in a polymer binder.

The polyvinyl carbazole or a derivative thereof is obtained, for example, from a vinyl monomer by cation polymerization or radical polymerization.

As the polysilane or a derivative thereof,
Chemical Review (Chem. Rev.) Vol. 89,
1359 (1989), British Patent GB230019
Compounds described in No. 6 published specification are exemplified. Although the synthesis methods described above can be used as the synthesis method, the Kipping method is particularly preferably used.

The polysiloxane or its derivative has almost no hole transporting property in the siloxane skeleton structure.
Those having the structure of the low-molecular-weight hole transporting material in the side chain or main chain are preferably used. In particular, those having a hole transporting aromatic amine in the side chain or main chain are exemplified.

The method for forming the hole transport layer is not limited.
In the case of the low-molecular-weight hole transport material, a method of forming a film from a mixed solution with a polymer binder is exemplified. In the case of a polymer hole transport material, a method of forming a film from a solution is exemplified.

The solvent used for film formation from a solution is not particularly limited as long as it can dissolve the hole transport material.
As the solvent, chloroform, methylene chloride, chlorine solvents such as dichloroethane, ether solvents such as tetrahydrofuran, toluene, aromatic hydrocarbon solvents such as xylene, acetone, ketone solvents such as methyl ethyl ketone,
Ester solvents such as ethyl acetate, butyl acetate and ethyl cellosolve acetate are exemplified.

As a method for forming a film from a solution, spin coating from a solution, casting, microgravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, spray coating, etc. Method, screen printing method, flexographic printing method,
A coating method such as an offset printing method and an inkjet printing method can be used.

As the polymer binder to be mixed, those which do not extremely inhibit charge transport are preferable, and those which do not strongly absorb visible light are suitably used. Examples of the polymer binder include polycarbonate, polyacrylate, polymethyl acrylate, polymethyl methacrylate, polystyrene, polyvinyl chloride, and polysiloxane.

The optimum value of the thickness of the hole transport layer depends on the material used, and may be selected so that the driving voltage and the luminous efficiency are appropriate. Is necessary, and if it is too thick,
The driving voltage of the device is undesirably high. Therefore, the thickness of the hole transport layer is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, and more preferably 5 nm to 200 nm.

When the organic EL device of the present invention has an electron transporting layer, known electron transporting materials can be used, and oxadiazole derivatives, anthraquinodimethane or its derivatives, benzoquinone or its derivatives, Naphthoquinone or a derivative thereof, anthraquinone or a derivative thereof, tetracyanoanthraquinodimethane or a derivative thereof, a fluorenone derivative, diphenyldicyanoethylene or a derivative thereof, a diphenoquinone derivative, or a metal complex of 8-hydroxyquinoline or a derivative thereof, polyquinoline or a derivative thereof, Examples thereof include polyquinoxaline or a derivative thereof, polyfluorene or a derivative thereof, and the like.

More specifically, JP-A-63-70257, JP-A-63-175860, and JP-A-2-1353
No. 59, 2-135361, 2-209
988, 3-37992, 3-152
No. 184 is exemplified.

Of these, oxadiazole derivatives,
Benzoquinone or a derivative thereof, anthraquinone or a derivative thereof, a metal complex of 8-hydroxyquinoline or a derivative thereof, polyquinoline or a derivative thereof, polyquinoxaline or a derivative thereof, polyfluorene or a derivative thereof are preferable, and 2- (4-biphenylyl) -5 is preferable. -(4-t-butylphenyl) -1,
3,4-oxadiazole, benzoquinone, anthraquinone, tris (8-quinolinol) aluminum, and polyquinoline are more preferred.

The method for forming the electron transporting layer is not particularly limited. For the low molecular weight electron transporting material, a vacuum evaporation method from powder or a method by film formation from a solution or a molten state is used. In the examples, a method by film formation from a solution or a molten state is exemplified. When forming a film from a solution or a molten state, a polymer binder may be used in combination.

The solvent used for film formation from a solution is not particularly limited as long as it can dissolve the electron transport material and / or the polymer binder. As the solvent, chloroform, methylene chloride, chlorine solvents such as dichloroethane, ether solvents such as tetrahydrofuran, aromatic hydrocarbon solvents such as toluene and xylene, acetone, ketone solvents such as methyl ethyl ketone, ethyl acetate, butyl acetate, Ester solvents such as ethyl cellosolve acetate are exemplified.

Examples of the film forming method from the solution or molten state include spin coating, casting, microgravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, spray coating. , A screen printing method, a flexographic printing method, an offset printing method, an ink-jet printing method, or the like.

As the polymer binder to be mixed, those which do not extremely inhibit charge transport are preferable, and those which do not strongly absorb visible light are suitably used. Examples of the polymer binder include poly (N-vinylcarbazole), polyaniline or a derivative thereof, polythiophene or a derivative thereof, poly (p-phenylenevinylene) or a derivative thereof, poly (2,5-thienylenevinylene) or a derivative thereof, and polycarbonate. , Polyacrylate, polymethyl acrylate, polymethyl methacrylate, polystyrene, polyvinyl chloride, or polysiloxane.

The optimum value of the film thickness of the electron transporting layer is different depending on the material used, and may be selected so that the driving voltage and the luminous efficiency have appropriate values. Necessary and too thick,
The driving voltage of the device is undesirably high. Therefore, the thickness of the electron transport layer is, for example, 1 nm to 1 μm, preferably 2 nm to 500 nm, and more preferably 5 nm to 200 nm.

The substrate on which the organic EL device of the present invention is formed comprises:
Any material may be used as long as it does not change when an electrode is formed and an organic layer is formed, and examples thereof include glass, plastic, a polymer film, and a silicon substrate. In the case of an opaque substrate, the opposite electrode is preferably transparent or translucent.

In the present invention, the anode is preferably transparent or translucent. As the material for the anode, a conductive metal oxide film, a translucent metal thin film, or the like is used.
Specifically, a film (NESA) formed using a conductive glass made of indium oxide, zinc oxide, tin oxide, or a complex thereof, such as indium tin oxide (ITO) or indium zinc oxide. Such)
And gold, platinum, silver, copper and the like are used, and ITO, indium / zinc / oxide, and tin oxide are preferable. Examples of the manufacturing method include a vacuum deposition method, a sputtering method, an ion plating method, and a plating method. Further, as the anode, an organic transparent conductive film such as polyaniline or a derivative thereof, polythiophene or a derivative thereof may be used. The thickness of the anode can be appropriately selected in consideration of light transmittance and electric conductivity.
m to 10 μm, preferably 20 nm to 1 μm, and more preferably 50 nm to 500 nm.
Further, on the anode, in order to facilitate charge injection, a layer made of a phthalocyanine derivative, a conductive polymer, carbon, or the like, or an average film thickness of 2 nm or less made of a metal oxide, a metal fluoride, an organic insulating material, or the like. A layer may be provided.

As a material for the cathode used in the organic EL device of the present invention, a material having a small work function is preferable. The alkali metal or an alloy containing an alkali metal can be used, but other metals, for example, beryllium,
Magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc,
Metals such as yttrium, indium, cerium, samarium, europium, terbium, ytterbium,
And alloys of two or more thereof, or alloys of one or more of them with one or more of gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten, tin, graphite or graphite An interlayer compound or the like is used. Examples of the alloy include a magnesium-silver alloy, a magnesium-indium alloy, a magnesium-aluminum alloy, an indium-silver alloy, a calcium-aluminum alloy, and the like. The cathode may have a laminated structure of two or more layers.

The thickness of the cathode can be appropriately selected in consideration of electric conductivity and durability. is there.

As a method for producing the cathode, a vacuum evaporation method, a sputtering method, a lamination method for thermocompression bonding a metal thin film, or the like is used. Further, a layer made of a conductive polymer or a layer made of a metal oxide, a metal fluoride, an organic insulating material, or the like having an average thickness of 2 nm or less may be provided between the cathode and the organic material layer. A protective layer for protecting the organic EL element may be provided. In order to use the organic EL device stably for a long period of time, it is preferable to attach a protective layer and / or a protective cover to protect the device from the outside.

As the protective layer, polymer compounds, metal oxides, metal fluorides, metal borides and the like can be used. Further, as the protective cover, a glass plate, a plastic plate having a surface subjected to a low water-permeability treatment, or the like can be used, and a method in which the cover is bonded to the element substrate with a heat effect resin or a photocurable resin and hermetically sealed is preferable. Used for If the space is maintained by using the spacer, it is easy to prevent the element from being damaged. If the space is filled with an inert gas such as nitrogen or argon, oxidation of the cathode can be prevented. Makes it easier to prevent the element from damaging the element. It is preferable to take any one or more of these measures.

To obtain planar light emission using the organic EL device of the present invention, a planar anode and a planar cathode may be arranged so as to overlap. Further, in order to obtain patterned light emission, a method in which a mask having a patterned window provided on the surface of the planar light emitting element is provided. There is a method of emitting light, a method of forming one or both of an anode and a cathode in a pattern. By forming a pattern by any of these methods and arranging some electrodes so that they can be independently turned on / off, a segment type display element capable of displaying numbers, characters, simple symbols, and the like can be obtained.
Further, in order to form a dot matrix element, both the anode and the cathode may be formed in a stripe shape and arranged orthogonally. A partial color display and a multi-color display can be achieved by a method of separately applying a plurality of types of polymer fluorescent substances having different emission colors or a method using a color filter or a fluorescence conversion filter. The dot matrix element can be driven passively or may be driven actively in combination with a TFT or the like. These display elements can be used as display devices for computers, televisions, mobile terminals, mobile phones, car navigation systems, viewfinders of video cameras, and the like.

Further, the planar light emitting element is a self-luminous thin type, and is a planar light source for a backlight of a liquid crystal display device.
Alternatively, it can be suitably used as a planar illumination light source. If a flexible substrate is used, it can be used as a curved light source or a display device.

[0106]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but it should not be construed that the present invention is limited thereto. Here, as for the number average molecular weight, the number average molecular weight in terms of polystyrene was determined by gel permeation chromatography (GPC) using chloroform as a solvent.

Reference Synthesis Example 1 <Synthesis of polymeric fluorescent substance 1> 2-Methoxy-5- (2-ethylhexyloxy) -p-xylylenedichloride
244 g (0.73 mmol) and 2,5-bis (chloromethyl) -3 ′-(3,7-dimethyloctyloxy)
1.83 g (4.5 mmol) of biphenyl and 1.63 g (3.9 mmol) of 2-methyl-5- (3,7-dimethyloctyl) -p-xylylenedibromide were added to 660 g of dehydrated 1,4-dioxane. Was dissolved. At this time, the ratio of each monomer to all monomers was 8 mol%, 49 mol%, and 43 mol%, respectively. This solution is
After the inside of the system was replaced with nitrogen by bubbling nitrogen for 20 minutes, the temperature was raised to 95 ° C. in a nitrogen atmosphere. To this solution, a solution in which 4.7 g of potassium-t-butoxide was dissolved in 80 g of dehydrated 1,4-dioxane was added dropwise in about 10 minutes. After the dropwise addition, polymerization was carried out at 97 ° C. for 2.5 hours. After the polymerization, the polymerization solution was cooled to 50 ° C., and neutralized by adding acetic acid. After cooling to room temperature, the polymerization solution was
The mixture was poured into 800 g of methanol, and the formed precipitate was collected. The precipitate was washed with ethanol and dried under reduced pressure. 1.5 g of the obtained polymer was mixed with 400 g of THF.
Was dissolved. This solution was poured into 800 g of methanol, and the generated precipitate was collected. The precipitate was washed with ethanol and dried under reduced pressure to obtain 1.4 g of a polymer. This polymer is referred to as polymeric fluorescent substance 1. The number average molecular weight of polymeric fluorescent substance 1 was 2 × 10 ⁵ .

Reference Synthesis Example 2 <Synthesis of polymeric fluorescent substance 2> 0.41 g of 1,4-bis (chloromethyl) -2- {4 '-(3,7-dimethyloctyloxy) phenyl} benzene (1. 0 mmol)
And 1,4-bis (bromomethyl) -2- (dimethyloctylsilyl) benzene 0.184 (0.43 mmol)
g and 2-methyl-5- (3,7-dimethyloctyl)-
0.18 (0.43 mmol) g of p-xylylene dibromide and 0.0533 g of 2-methoxy-5- (2-ethylhexyloxy) -p-xylylene dichloride
(0.16 mmol) was dissolved in 200 g of 1,4-dioxane (dehydrated). At this time, the ratio of each monomer to all monomers was 50 mol%, 21 mol%, 21 mol%, and 8 mol%, respectively. This solution is
After purging the system with nitrogen by bubbling nitrogen for minutes,
The temperature was raised to 95 ° C. in a nitrogen atmosphere. Then in this solution,
In advance, 1.1 g of potassium-t-butoxide was dissolved in 30 ml of 1,4-dioxane (dehydrated), and the solution was replaced with nitrogen gas by bubbling with nitrogen gas.
It was dropped in about 10 minutes. After the addition, the reaction was continued at 95 ° C. for 2 hours. The reaction was performed in a nitrogen gas atmosphere.
Next, after cooling this solution, acetic acid was added for neutralization. Methanol was added to this solution, and the generated precipitate was collected. Next, the precipitate was washed with ethanol and dried under reduced pressure to obtain 0.40 g of a polymer. Next, this precipitate is
After dissolving in about 120 g of HF, the solution was reprecipitated and purified by adding methanol. The obtained precipitate was washed with ethanol and then dried under reduced pressure to obtain 0.36 g of a polymer.
I got The obtained polymer is called polymeric fluorescent substance 2. The number average molecular weight in terms of polystyrene of the polymeric fluorescent substance 2 is:
It was 1.2 × 10 ⁵ .

Example 1 <Preparation and Evaluation of Element>
3% by weight of a phenolic compound represented by the following formula (Sumitize Chemical Industry Co., Ltd., trade name: Sumilize)
A 0.6% by weight toluene solution of polymeric fluorescent substance 1 containing (rGA-80) was prepared.

Embedded image Poly (3,4) ethylenedioxythiophene / polystyrene sulfonic acid (manufactured by Bayer, By) was applied to a glass substrate on which an ITO film having a thickness of 150 nm was formed by a sputtering method.
(Tron P TP AI 4083) was formed into a film having a thickness of 50 nm by spin coating and dried on a hot plate at 120 ° C. for 10 minutes. A light-emitting layer having a thickness of 80 nm was formed thereon by spin coating using the toluene solution of the polymeric fluorescent substance 1. Furthermore, after drying this under reduced pressure at 80 ° C. for 1 hour, lithium fluoride was vapor-deposited in an amount corresponding to about 0.4 nm, and then calcium was deposited to a thickness of 40 nm.
Aluminum was further evaporated to a thickness of 70 nm to produce an organic EL device. The degree of vacuum at the time of deposition is 8 × 10 ^-6
Torr or less. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. Under a nitrogen stream, the device was driven with a constant current at a current density of 25mA / cm ^2, emission luminance of 1,800 cd / m ² is, becomes 1600 cd / m ² (retention 89% brightness) after 1 hour,
It halved in about 60 hours.

Comparative Example 1 Sumilizer G was added to a toluene solution of polymeric fluorescent substance 1.
Example 1 except that A-80 was contained at 11.2% by weight.
An organic EL device was produced in the same manner as in the above. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. When a constant current drive was performed at a current density of 25 mA / cm ² under a nitrogen stream, the emission luminance of 2000 cd / m ² was reduced by half in about 5 hours.

Comparative Example 2 Sumilizer G was added to a toluene solution of polymeric fluorescent substance 1.
An organic EL device was produced in the same manner as in Example 1 except that A-80 was not contained. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. Under a nitrogen stream, the device was driven with a constant current at a current density of 25mA / cm ^2, emission luminance of 1400cd / m ² is, after 1 hour attenuated to 900 cd / m ² (retention 64% brightness), in about 50 hours Halved.

Comparative Example 3 40 n of calcium was deposited without depositing lithium fluoride.
Example 1 except that m and aluminum were deposited to a thickness of 70 nm.
An organic EL device was produced in the same manner as in the above. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. Under a nitrogen stream, the device was driven with a constant current at a current density of 25mA / cm ^2, emission luminance of 1400cd / m ² is 1 hour after the 950 cd / m ² (luminance retention of 67
%)Became.

Example 2 <Preparation and evaluation of device>
A 0.75 wt% toluene solution of the polymeric fluorescent substance 2 containing 0 wt% Sumilizer GA-80 was prepared. I
Bytron P TP AI on glass substrate with TO film
The suspension of 4083 was formed into a film having a thickness of 50 nm by spin coating, and dried on a hot plate at 120 ° C. for 10 minutes. A light emitting layer having a thickness of 80 nm was formed thereon by spin coating using the toluene solution of the polymeric fluorescent substance 2. Further, this was dried at 80 ° C. for 1 hour under reduced pressure, and then, as a cathode, rubidium was vapor-deposited in an amount corresponding to about 0.4 nm, and aluminum was vapor-deposited to a thickness of 70 nm.
An element was manufactured. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. When a constant current drive was performed at a current density of 25 mA / cm ² under a nitrogen stream, the emission luminance of 2200 cd / m ² was 1 hour after 1 hour.
800 cd / m ² (luminance retention rate: 82%).

Comparative Example 4 Sumilizer G was added to a toluene solution of polymeric fluorescent substance 2.
An organic EL device was produced in the same manner as in Example 2 except that A-80 was not contained. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. Under a nitrogen stream, the device was driven with a constant current at a current density of 25mA / cm ^2, emission luminance of 2100cd / m ² is, after 1 hour was attenuated to 1430cd / m ² (retention of 68% of the luminance).

Example 3 <Preparation and evaluation of device> An organic EL device was prepared in the same manner as in Example 2, except that cesium was vapor-deposited in an amount of about 0.4 nm instead of rubidium. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. When a constant current drive was performed at a current density of 25 mA / cm ² under a nitrogen stream, the emission luminance of 2500 cd / m ² was 1
After 2130 cd / m ² (85% luminance retention)
Became.

Comparative Example 5 Sumilizer G was added to a toluene solution of polymeric fluorescent substance 2.
An organic EL device was produced in the same manner as in Example 3 except that A-80 was not contained. When a voltage was applied to the obtained device under a nitrogen stream, yellow EL emission was observed. Under a nitrogen stream, the device was driven with a constant current at a current density of 25mA / cm ^2, emission luminance of 2200cd / m ² is, after 1 hour was attenuated to 1200 cd / m ² (luminance retention of 55%).

[0117]

The organic EL device of the present invention has a longer life while maintaining the characteristics of the organic EL device, and thus can be preferably used as devices such as a planar light source as a backlight and a flat panel display.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H091 FA43Z FA44Z FB06 FB13 LA01 LA15 3K007 AB00 AB02 AB04 AB06 BA06 CA00 CA01 CA05 CA06 CB01 CB03 DA00 DB03 EB00 FA01

Claims (9)

[Claims] At least one electrode is provided between a pair of anodes and cathodes, at least one of which is transparent or translucent.
In an organic electroluminescent device having a plurality of organic layers, at least one of the organic layers is a group consisting of an aryl group having 6 to 20 carbon atoms having a hydroxyl group and a heterocyclic compound group having 4 to 20 carbon atoms having a hydroxyl group. At least one compound having from 1 to 4 at least one compound group selected from the group consisting of a compound having a molecular weight of 200
0 or less, and the total amount of the compounds is 0.02% by weight to 9% by weight based on the weight of the layer containing the compound.
And a layer containing an alkali metal, an alloy containing an alkali metal, or a compound containing an alkali metal (including a case where the layer is part or all of a cathode, adjacent to a layer containing the compound, ). An organic electroluminescence device comprising: 2. The organic electroluminescent device according to claim 1, wherein the aryl group having a hydroxyl group is a group represented by the following general formula (1). Embedded image [Here, Ar ₁ represents an aryl group having 6 to 20 carbon atoms. R ₁ represents a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms or an alkoxy group having a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms;
Represents an integer of 1 to 3, and n represents 0 or an integer of 1 or more.
When n is 2 or more, R ₁ may be the same or different. (M + n) ≦ (the number of hydrogen atoms possessed when Ar ₁ is unsubstituted). ] 3. The organic electroluminescent device according to claim 1, wherein the alkali metal is lithium. 4. The organic electroluminescent device according to claim 1, wherein at least one of the layers containing a compound having a molecular weight of 2000 or less is a light emitting layer. 5. The light-emitting layer has fluorescence in a solid state, has a number average molecular weight of 1 × 10 ³ to 1 × 10 ⁸ in terms of polystyrene, and has at least one repeating unit represented by the following general formula (2). 5. The organic electroluminescent device according to claim 4, wherein the organic electroluminescent device contains a polymer fluorescent material containing various kinds. Embedded image —Ar ₂ — (CR ₂ = CR ₃ ) _k — (2) [where Ar ₂ is a divalent group that forms a carbon-carbon bond with two adjacent groups. An arylene group comprising 6 to 60 carbon atoms participating in conjugation, or 4 to 60 carbon atoms participating in conjugation.
Or less, and the arylene group and the heterocyclic compound group may further have a substituent. R ₂ and R ₃ each independently represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 60 carbon atoms, or a heterocyclic compound group having 4 to 60 carbon atoms. And a group selected from the group consisting of a cyano group, and the aryl group and the heterocyclic compound group may further have a substituent. k is 0 or 1. ] 6. A planar light source using the organic electroluminescence device according to claim 1. 7. A segment display device using the organic electroluminescence element according to claim 1. 8. A dot matrix display device using the organic electroluminescence device according to claim 1. 9. A liquid crystal display device comprising the organic electroluminescence element according to claim 1 as a backlight.