JPH11102784A - Organic electroluminescent device material and organic electroluminescent device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescence(EL) element high in luminous efficiency and superior in emission life by using a specific organic EL element material. SOLUTION: Organic EL element material is expressed by a formula, where Q<1> , Q<2> independently represents a hydrogen atom, a cyano group, a substituted or unsubstituted monocyclic group and a substituted or unsubstituted condensed polycyclic groups, R<1> -R<12> and R<13> -R<32> independently represents a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted monocyclic group and a substituted or unsubstituted condensed polycyclic group, X<1> -X<4> independently represents O, S, C=O, C≡C, CZ<1> =CZ<2> , SO2 , or (CH2 )x-O-(CH2 )y, where Z<1> and Z<4> respectively independently represents a hydrogen atom or a cyano group, and x and y represent respectively positive integers of 0-20, but there is no case where x+y=0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

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

[0003] Conventional organic EL devices have a higher driving voltage and lower luminous brightness and luminous efficiency than inorganic EL devices.
In addition, the characteristic deterioration was remarkable, and it had not been put to practical use.
2. Description of the Related Art In recent years, an organic EL in which thin films containing an organic compound having high fluorescence quantum efficiency and emitting light at a low voltage of 10 V or less are laminated.
Devices have been reported and are of interest (see Applied Physics Letters, vol. 51, p. 913, 1987). In this method, the metal chelate complex is converted into a phosphor layer,
High brightness green light emission is obtained by using an amine compound for the hole injection layer, and the brightness is 100 c at a DC voltage of 6 to 7 V.
d / m ² and maximum luminous efficiency of 1.5 lm / W,
Has performance close to the practical range. However, organic EL devices up to now have improved light emission intensity due to the improved structure, but do not yet have sufficient light emission luminance.
In addition, there is a major problem that the stability upon repeated use is poor.

[0004] In order to improve the luminous efficiency of an organic EL device, there is disclosed a technique in which a luminescent layer is formed by doping a host material, which is a luminescent material, with a guest material. For example, an organic EL device in which a light emitting layer is doped with a tris (8-hydroxyquinoline) aluminum complex as a host material and a coumarin dye or a DCM dye as a fluorescent guest material (Journal of Applied Physics, Vol. 65,
3610, 1989), N, N-diphenyl-N, N '-(3-methylphenyl) -1,1'-biphenyl-4,4'-diamine as a host material and rubrene as a fluorescent guest material EL device doped as a material (see Japanese Journal of Applied Physics, Vol. 34, page L824, 1995)
However, the luminous efficiency of these organic EL devices was not sufficient. For these reasons, there is currently a need for the development of fluorescent guest materials that can be easily uniformly doped into the light emitting layer, and organic EL devices that have higher luminous efficiency and excellent luminous life. It is.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic EL device having high luminous efficiency and excellent luminous life. As a result of extensive studies by the inventors, general formulas [1] to
It has been found that an organic EL device using at least one organic EL device material of the compound represented by [3] in at least one layer has high luminous efficiency in the yellow to red spectral region and excellent luminous life, and has led to the present invention. Was.

That is, the present invention relates to an organic electroluminescent device material represented by the following general formula [1]. General formula [1]

Embedded image [In the formula, Q ¹ and Q ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, or a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² and R ^{13 to} R ³² are each independently
Hydrogen atom, halogen atom, cyano group, nitro group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted Represents an arylthio group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkylamino group, or a substituted or unsubstituted arylamino group. X ^{1 to} X
⁴ are independently O, S, C = O, C≡C, CZ
_{^{1 = CZ 2, SO 2,}} (CH 2) x-O- (CH 2)
y represents a substituted or unsubstituted alkylene group or a substituted or unsubstituted aliphatic ring residue. Where Z ¹ and Z ²
Each independently represents a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, and x and y are
Each represents a positive integer of 0 to 20, but does not satisfy x + y = 0. R ^{1 to} R ¹² or R ^{13 to} R ³² may be bonded by adjacent groups to form a new ring. ]

Further, the present invention is an organic electroluminescent device material represented by the following general formula [2]. General formula [2]

Embedded image [Wherein, Q ¹ and Q ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, or And a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² and R ^{13 to} R ³² each independently represent a hydrogen atom, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted Aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted arylthio group, substituted or unsubstituted monocyclic group, substituted or unsubstituted fused polycyclic group, substituted or unsubstituted amino group, substituted or unsubstituted Represents a substituted alkylamino group or a substituted or unsubstituted arylamino group. X ^{1 to} X ⁴ are each independently O, S, C = O,
C≡C, CZ ¹ = CZ ² , SO ₂ , (CH ₂ ) x—O—
(CH ₂ ) y represents a substituted or unsubstituted alkylene group or a substituted or unsubstituted aliphatic ring residue. Where Z ¹
And Z ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, and x and y each represent 0 Represents a positive integer of ２０20, but x +
y = 0 never occurs. R ^{1 to} R ¹² or R ¹³ to
R ³² may be bonded via adjacent groups to form a new ring. ]

Further, the present invention is an organic electroluminescent device material represented by the following general formula [3]. General formula [3]

Embedded image [In the formula, Q ¹ and Q ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, or a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² and R ^{13 to} R ³² are each independently
Hydrogen atom, halogen atom, cyano group, nitro group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted Represents an arylthio group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkylamino group, or a substituted or unsubstituted arylamino group. Y ^{1 to} Y
⁸ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monocyclic group having 6 to 16 carbon atoms, or a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² or R ^{13 to} R ³² may be bonded by adjacent groups to form a new ring. ]

Further, the present invention relates to an organic electroluminescence device in which a plurality of organic compound thin films including a light emitting layer are formed between a pair of electrodes, wherein the light emitting layer has a general formula [1] to
[3] An organic electroluminescence device, which is a layer containing the organic electroluminescence device material according to any one of the above.

Further, according to the present invention, the light emitting layer comprises a host material and a doping material, and the doping material has the general formula [1]
[3] The organic electroluminescence device according to any one of [1] to [3], which is the organic electroluminescence device material according to any one of [1] to [3].

Further, according to the present invention, there is provided a method in which a light-emitting layer is provided between a light-emitting layer and a cathode.
The organic electroluminescence device as described above, wherein four electron injection layers and an electron transport layer are formed.

Further, according to the present invention, there is provided a light-emitting device in which
The organic electroluminescence device according to the above, wherein four hole injection layers and a hole injection layer are formed.

BEST MODE FOR CARRYING OUT THE INVENTION

In the compounds represented by the general formulas [1] to [3], R ^{1 to} R ³² each independently represent a hydrogen atom, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkyl group. Unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted arylthio group,
Substituted or unsubstituted cycloalkyl group, substituted or unsubstituted monocyclic group, substituted or unsubstituted fused polycyclic group, substituted or unsubstituted amino group, substituted or unsubstituted alkylamino group, substituted or unsubstituted Represents an arylamino group.

Specific examples of the halogen atom of R ^{1 to} R ^{32 in} the compounds represented by the general formulas [1] to [3] in the present invention include chlorine, bromine, iodine and fluorine, and specific examples of the alkyl group As a methyl group, an ethyl group, a propyl group,
Butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, stearyl group, trichloromethyl group, etc. Specific examples of cycloalkyl include cyclopentane ring, cyclohexane ring and the like. There is.

Specific examples of the alkoxy groups represented by R ^{1 to} R ^{32 in} the compounds represented by the general formulas [1] to [3] in the present invention include methoxy, ethoxy, n-butoxy and te.
rt-butoxy group, trichloromethoxy group, trifluoroethoxy group, pentafluoropropoxy group, 2,2,2
3,3-tetrafluoropropoxy group, 1,1,1,
3,3,3-hexafluoro-2-propoxy group, 6-
(Perfluoroethyl) hexyloxy group and the like. Specific examples of the aryloxy group include a phenoxy group and a p-
Examples include a nitrophenoxy group, a p-tert-butylphenoxy group, a 3-fluorophenoxy group, a pentafluorophenyl group, and a 3-trifluoromethylphenoxy group.

Specific examples of the alkylthio group represented by R ^{1 to} R ^{32 in} the compounds represented by the general formulas [1] to [3] in the present invention include a methylthio group, an ethylthio group, a tert-butylthio group, a hexylthio group, Examples thereof include an octylthio group and a trifluoromethylthio group. Specific examples of the arylthio group include a phenylthio group, a p-nitrophenylthio group, and a p-nitrophenylthio group.
Examples include a tert-butylphenylthio group, a 3-fluorophenylthio group, a pentafluorophenylthio group, and a 3-trifluoromethylphenylthio group.

In the present invention, the monocyclic group represented by R ^{1 to} R ^{32 in} the compounds represented by the general formulas [1] to [3] is phenyl, thionyl, thiophenyl, furanyl, pyrrolyl, imidazolyl, There are pyrazolyl group, pyridyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, oxazolyl group, thiazolyl group, oxadiazolyl group, thiadiazolyl group, imidadiazolyl group and the like.

The condensed polycyclic group represented by R ^{1 to} R ^{32 in} the compounds represented by the general formulas [1] to [3] in the present invention includes naphthyl, anthryl, phenanthryl, fluorenyl, pyrenyl, indole and the like. Group, purine group, quinoline group, isoquinoline group, sinoline group, quinoxaline group, benzoquinoline group, fluorenone group, carbazole group, oxazole group, oxadiazole group, thiazole group, thiadiazole group, triazole group, imidazole group, benzoxazole group , Benzothiazole, benzotriazole, benzimidazole, bisbenzoxazole, bisbenzothiazole, bisbenzimidazole, anthrone, dibenzofuran, dibenzothiophene, anthraquinone, acridone, phenothiazine, Lysine group, dioxane group, a morpholine group.

Specific examples of the amino group represented by R ^{1 to} R ^{32 in} the compounds represented by the general formulas [1] to [3] in the present invention include an amino group, a bis (acetoxymethyl) amino group and a bis (acetoxyethyl) group. ) Amino group, bisacetoxypropyl) amino group, bis (acetoxybutyl) amino group and the like. Specific examples of the alkylamino group include an ethylamino group, a diethylamino group, a dipropylamino group, a dibutylamino group, and a benzylamino group. Specific examples of the arylamino group include a phenylamino group, a (3-methylphenyl) amino group, and a (4-methylphenyl) amino group. Specific examples of the phenylamino group include: Phenylamino group, phenylmethylamino group, diphenylamino group, ditolylamino group, dibiphenylamino group, 4-methylbiphenyl) amino group, di (3-methylphenyl) amino group, di (4-methylphenyl) amino group, naphthylphenylamino group, bis [4- (α, α′-dimethylbenzyl) phenyl] amino group Etc.

Adjacent groups R ^{1 to} R ³² are bonded to each other to form a saturated or unsaturated ring such as a phenyl ring, a naphthyl ring, an anthryl ring, a pyrenyl ring, a carbazole ring, a benzopyranyl ring and a cyclohexyl ring. May be formed.

Q ¹ and Q of the compounds of the general formulas [1] to [3]
² is each independently a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group,
Represents a substituted or unsubstituted fused polycyclic group. Alkyl group,
Specific examples of the monocyclic group and the condensed polycyclic group include the alkyl groups, monocyclic groups, and condensed polycyclic groups described for R ^{1 to} R ³² .

The general formulas [1] and [2] in the present invention
X ^{1 to} X ⁴ of the compound represented by are each independently
O, S, C = O, CZ ¹ = CZ ² , C≡C, SO ₂ ,
(CH ₂₎ represents the x-O-(CH ₂₎ y, a substituted or unsubstituted alkylene, substituted or unsubstituted aliphatic ring residue. Here, x and y each represent a positive integer of 0 to 20; however, x + y = 0 does not occur. Also, Z
¹ and Z ² are each independently a hydrogen atom, a cyano group,
Represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, or a substituted or unsubstituted fused polycyclic group. Specific examples of the alkyl group, the monocyclic group, and the condensed polycyclic group include the above-described R ¹
Alkyl groups described to R ^32, a monocyclic group, and condensed polycyclic group. As a substituted or unsubstituted alkylene group, an alkylene group having 1 to 20 carbon atoms or a substituted product thereof, as a substituted or unsubstituted aliphatic ring residue, a cyclopentyl ring, a cyclohexyl ring, a methylcyclohexyl ring,
Examples thereof include a divalent residue of an aliphatic ring having 5 to 7 carbon atoms such as a cycloheptyl ring. Examples of the substituent of the substituted alkylene group or the substituted aliphatic ring residue of X ^{1 to} X ⁴ include the substituents represented by R ^{1 to} R ³² . Preferred as the substituted alkylene group for X ^{1 to} X ⁴ are 2-phenylisopropylene group, dichloromethylene group, difluoromethylene group, benzylene group, α-phenoxybenzylene group, α, α′-dimethylbenzylene group, α -Benzyloxybenzylene group and the like.

In the present invention, Y ¹ to Y ⁸ of the compound represented by the general formula [3] represent a substituted or unsubstituted C ¹ -C 1.
20 alkyl groups, substituted or unsubstituted 6-1 carbon atoms
6 represents a monocyclic group or a condensed polycyclic group. Alkyl group, monocyclic group,
Specific examples of the condensed polycyclic group include the alkyl groups, monocyclic groups, and condensed polycyclic groups described for R ^{1 to} R ³² .

Q in the present invention¹, Q^TwoAn alkyl group of
A monocyclic group, a fused polycyclic group, and R¹~ R³²A shown by
Alkyl group, alkoxy group, aryloxy group, alkyl
Thio group, arylthio group, cycloalkyl group, monocyclic group,
Condensed polycyclic group, amino group, alkylamino group, aryl group
A amino group, and X¹~ X^TwoAn alkylene group, and Y ¹
~ Y⁸Alkyl group, monocyclic group, fused polycyclic group, Z¹and
Z^TwoMay be substituted with an alkyl group, a monocyclic group, or a condensed polycyclic group.
Representative examples of the substituent include the following substituents.

Examples of the halogen atom include chlorine, bromine, iodine and fluorine. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a sec-butyl group, a ter
t-butyl group, pentyl group, hexyl group, heptyl group,
There are an octyl group, a stearyl group, a trichloromethyl group and the like. As the cycloalkyl, a cyclopentane ring, a cyclohexane ring, a 1,3-cyclohexadienyl group, a 2-
Examples thereof include a cyclopenten-1-yl group and a 2,4-cyclopentadiene-1-ylenyl group.

Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-butoxy group, a tert-butoxy group, a trichloromethoxy group, a trifluoroethoxy group, a pentafluoropropoxy group, a 2,2,3,3-tetrafluoropropoxy group. , 1,1,1,3,3,3-hexafluoro-2-propoxy group, 6- (perfluoroethyl) hexyloxy group and the like.
Phenoxy group, p-nitrophenoxy group, p-tert
-Butylphenoxy group, 3-fluorophenoxy group, pentafluorophenyl group, 3-trifluoromethylphenoxy group and the like.

As the alkylthio group, a methylthio group,
There are an ethylthio group, a tert-butylthio group, a hexylthio group, an octylthio group, a trifluoromethylthio group and the like. As the arylthio group, a phenylthio group, a p-nitrophenylthio group, a p-tert-butylphenylthio group, a 3-fluorophenyl A thio group, a pentafluorophenylthio group, a 3-trifluoromethylphenylthio group, and the like.

As the aryl group, phenyl group, biphenyl group, terphenyl group, naphthyl group, anthryl group,
There are a phenanthryl group, a fluorenyl group, a pyrenyl group, and the like, and examples of the heterocyclic group include a pyrrole group, a pyrroline group, a pyrazole group, a pyrazoline group, an imidazole group, a triazole group, a pyridine group, a pyridazine group, a pyrimidine group, a pyrazine group, and a triazine group. , Indole, purine, quinoline, isoquinoline, sinoline, quinoxaline, benzoquinoline, fluorenone, carbazole, oxazole, oxadiazole, thiazole, thiadiazole, triazole, imidazole, benzo Oxazole group, benzothiazole group, benzotriazole group, benzimidazole group, bisbenzooxazole group, bisbenzothiazole group, bisbenzimidazole group, anthrone group, dibenzofuran group, dibenzothiophene group Anthraquinone group, acridone group, a phenothiazine group, a pyrrolidine group, dioxane group,
A morpholine group.

Examples of the amino group include an amino group, a bis (acetoxymethyl) amino group, a bis (acetoxyethyl) amino group, a bis (acetoxypropyl) amino group and a bis (acetoxybutyl) amino group. Examples are ethylamino, diethylamino,
There are a dipropylamino group, a dibutylamino group, a benzylamino group and a dibenzylamino group. Specific examples of the arylamino group include a phenylamino group, a (3-methylphenyl) amino group, and a (4-methylphenyl) amino group. , Phenylmethylamino group, diphenylamino group, bis (4
-Phenoxyphenyl) amino group, bis (4-biphenyl) amino group, bis [4- (4-tolyl) phenyl] amino group, bis (3-methylphenyl) amino group, bis (4-methylphenyl) amino group, A naphthylphenylamino group and a bis [4- (α, α′-dimethylbenzyl) phenyl] amino group.

In the present invention, the compounds represented by the general formulas [1] to [3] can be synthesized, for example, by the following method. It can be obtained by heating the following general formulas [4] and [5] in tetrahydrofuran in the presence of titanium tetrachloride and zinc. Hereinafter, typical examples of the compound of the present invention are specifically illustrated in Table 1, but the present invention is not limited to the following typical examples.

The general formula [4]

Embedded image

General formula [5]

Embedded image [Wherein, R ^{1 to} R ¹² are the same as described above. ]

[0032]

[Table 1]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

The compounds represented by the general formulas [1] to [3] have two olefin sites (> C = C <) in one molecule. Due to the geometric isomer of this olefin moiety,
The compounds represented by the general formulas [1] to [3] have a combination of a cis-form and a trans-form, but the compound of the present invention may be any one of them and may be a mixture thereof.

The organic EL device is a device in which a single or multilayer organic thin film is formed between an anode and a cathode. In the case of a single layer type, a light emitting layer is provided between an anode and a cathode. The light-emitting layer contains a light-emitting material and may further contain a hole-injection material or an electron-injection material for transporting holes injected from an anode or electrons injected from a cathode to the light-emitting material. The electron injection material is a material capable of injecting electrons from the cathode, and the electron transport material is a material capable of transporting the injected electrons to the light emitting layer. The hole injection material is a material capable of injecting holes from the anode, and the hole transport material is a material capable of transporting the injected holes to the light emitting layer. The multilayer type includes (anode / hole injection layer / light-emitting layer / cathode), (anode / hole injection layer /
(Hole transport layer / light emitting layer / cathode), (anode / light emitting layer / electron injection layer / cathode), (anode / light emitting layer / electron transport layer / electron injection layer / cathode), (anode / hole injection layer / emission) Layer / electron injection layer / cathode), (anode / hole injection layer / hole transport layer / light emitting layer /
There is an organic EL device having a multilayer structure of (electron transport layer / electron injection layer / cathode). The multilayer hole transport layer and electron transport layer may be composed of a plurality of layers. The compounds represented by the general formulas [1] to [3] of the present invention are compounds having strong fluorescence in a solid state and have excellent electroluminescence properties, and thus can be used in a light emitting layer as a light emitting material.
Further, by doping the compounds of the general formulas [1] to [3] as the doping material in the light emitting layer at the optimum ratio in the light emitting layer, it is possible to select the high light emitting efficiency and the light emitting wavelength optimally. .

By using a compound of the general formulas [1] to [3] as a doping material (guest material) as a host material of the light emitting layer, an organic EL device having high emission luminance can be obtained. The compounds of the general formulas [1] to [3] are desirably contained in the light-emitting layer in a range of 0.001% by weight to 50% by weight relative to the host material, and more preferably 0.1% by weight.
The range from 01% by weight to 10% by weight is effective.

Examples of the host material which can be used in combination with the compounds of the general formulas [1] to [3] include quinoline metal complex, oxadiazole, benzothiazole metal complex, benzoxazole metal complex, benzimidazole metal complex, triazole, imidazole , Oxazole, oxadiazole, stilbene, butadiene, benzidine triphenylamine, styrylamine triphenylamine, diamine triphenylamine fluorenone, diaminoanthracene triphenylamine, diaminophenanthrene triphenylamine, anthraquinodimethane, Diphenoquinone, thiadiazole, tetrazole, perylenetetracarboxylic acid, fluorenylidenemethane, anthraquinodimethane, triphenylene, anthrone and their derivatives, and , Polyvinylcarbazole, there polymeric materials and the like of the conductive polymer and polysilane, and the like. Table 2 below
However, the present invention is not limited to the following representative examples.

[0043]

[Table 2]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

Using the general formulas [1] to [3] as the host material, the emission color can be changed by using a doping material. As the doping material used together with the general formulas [1] to [3], anthracene, naphthalene, phenanthrene, pyrene, tetracene, coronene,
Chrysene, fluorescein, perylene, phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, coumarin, oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine,
Cyclopentadiene, quinoline metal complex, aminoquinoline metal complex, imine, diphenylethylene, vinylanthracene, diaminocarbazole, pyran, thiopyran, polymethine, merocyanine, imidazole chelated oxinoid compounds, quinacridone, rubrene and the like, and derivatives thereof. However, the present invention is not limited to this.

For the light emitting layer, a hole injection material or an electron injection material can be used if necessary, in addition to the light emitting material and the doping material.

The organic EL element has a multi-layer structure, so that it is possible to prevent a decrease in luminance and life due to quenching. If necessary, a combination of two or more kinds of light emitting materials, doping materials, hole injecting materials for injecting carriers, and electron injecting materials can also be used. Also,
The hole injection layer, the light-emitting layer, and the electron injection layer may each be formed in a layer structure of two or more layers, and an element structure in which holes or electrons are efficiently injected from the electrode and transported in the layer is selected. You.

The conductive material used for the anode of the organic EL element preferably has a work function of more than 4 eV, and includes carbon, aluminum, vanadium, iron, cobalt,
Nickel, tungsten, silver, gold, platinum, palladium and the like and alloys thereof, ITO substrate, metal oxide such as tin oxide and indium oxide called NESA substrate, and organic conductive resin such as polythiophene and polypyrrole are used. . The conductive material used for the cathode is preferably one having a work function of less than 4 eV, such as magnesium, calcium, tin, lead, titanium, yttrium,
Lithium, ruthenium, manganese and the like and alloys thereof are used. Representative examples of the alloy include magnesium / silver, magnesium / indium, and lithium / aluminum, but are not limited thereto. The ratio of the alloy is controlled by the heating temperature, atmosphere, and degree of vacuum, and an appropriate ratio is selected. The anode and the cathode may be formed by two or more layers if necessary.

In the organic EL device, it is desirable that at least one of the organic EL devices is sufficiently transparent in an emission wavelength region of the device in order to emit light efficiently. Further, it is desirable that the substrate is also transparent. The transparent electrode is set so as to secure a predetermined translucency by a method such as vapor deposition or sputtering using the above conductive material. The electrode on the light emitting surface desirably has a light transmittance of 10% or more. The substrate is not limited as long as it has mechanical and thermal strength and is transparent, but examples thereof include a transparent resin such as a glass substrate, a polyethylene plate, a polyether sulfone plate, and a polypropylene plate. .

Each layer of the organic EL device according to the present invention can be formed by any of dry film forming methods such as vacuum evaporation and sputtering and wet film forming methods such as spin coating and dipping. The thickness is not particularly limited, but each layer needs to be set to an appropriate thickness. If the film thickness is too large, a large applied voltage is required to obtain a constant light output, resulting in poor efficiency. If the film thickness is too small, pinholes and the like are generated, and sufficient light emission luminance cannot be obtained even when an electric field is applied. Normal thickness is 5nm to 10μ
The range of m is suitable, but the range of 10 nm to 0.2 μm is more preferable.

In the case of the wet film forming method, a material for forming each layer is dissolved or dispersed in an appropriate solvent such as chloroform, tetrahydrofuran, dioxane or the like to form a thin film.
The solvent may be any. In any of the thin films, a suitable resin or additive may be used to improve film forming properties, prevent pinholes in the film, and the like. Examples of such a resin include insulating resins such as polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyurethane, polysulfone, polymethyl methacrylate, polymethyl acrylate, and cellulose, and poly-N-.
Examples include photoconductive resins such as vinyl carbazole and polysilane, and conductive resins such as polythiophene and polypyrrole. Examples of the additive include an antioxidant, an ultraviolet absorber, and a plasticizer.

The hole injecting material or the hole transporting material has the ability to inject holes, has an excellent hole injecting effect on the light emitting layer or the light emitting material, and has an exciton generated in the light emitting layer. Compounds which prevent migration to the electron injection layer or the electron injection material and have excellent thin film forming ability are exemplified. Specifically, phthalocyanine-based compounds, naphthalocyanine-based compounds, porphyrin-based compounds, oxadiazole, triazole, imidazole, imidazolone, imidazolethione, pyrazoline, pyrazolone, tetrahydroimidazole, oxazole, oxadiazole, hydrazone, acylhydrazone, poly Arylalkane, stilbene, butadiene, benzidine-type triphenylamine,
Examples include, but are not limited to, styrylamine-type triphenylamine, diamine-type triphenylamine, and derivatives thereof, and polymer materials such as polyvinyl carbazole, polysilane, and conductive polymers.

The electron injecting material or the electron transporting material has a capability of injecting electrons, has an excellent electron injecting effect on the light emitting layer or the light emitting material, and has a hole injecting layer for excitons generated in the light emitting layer. Alternatively, a compound which prevents migration to a hole injecting material and has excellent thin film forming ability can be used. For example, quinoline metal complex, oxadiazole, benzothiazole metal complex, benzoxazole metal complex, benzimidazole metal complex, fluorenone, anthraquinodimethane, diphenoquinone, thiopyrandioxide, oxadiazole, thiadiazole, tetrazole, perylenetetracarbon Examples include, but are not limited to, acids, fluorenylidenemethane, anthraquinodimethane, anthrone, and derivatives thereof. Alternatively, an electron accepting material may be added to the hole injecting material and an electron donating material may be added to the electron injecting material to sensitize the material.

In order to improve the stability of the organic EL device obtained according to the present invention with respect to temperature, humidity, atmosphere, etc., a protective layer is provided on the surface of the device or silicon oil or the like is sealed to protect the entire device. It is also possible.

[0067]

The present invention will be described in more detail with reference to the following examples.

Synthesis Method of Compound (1) 100 ml of THF is put in a flask, cooled by an ice bath, and 12 ml of titanium tetrachloride is added dropwise. Then, 1-
6 g of formyl-4- [N, N′-di (4- (α, α′-dimethylbenzyl) phenyl)] amino-naphthalene is charged into the flask, and 8 g of zinc powder is added little by little.
After the addition, the flask was heated and reacted under reflux for 5 hours. After completion of the reaction, water was added and the resulting precipitate was collected by filtration. The precipitate was subjected to column purification using silica gel, and then to sublimation purification. The formation of the compound was confirmed by NMR, FD-MS, and IR.

Example 1 On a cleaned glass plate with ITO electrodes, N, N '-(3
-Methylphenyl) -N, N'-diphenyl-1,1-
Biphenyl-4,4-diamine (TPD) was vacuum-deposited to obtain a hole injection layer having a thickness of 20 nm. Next, the compound (1) was deposited to form a light emitting layer having a thickness of 40 nm, and a tris (8-hydroxyquinoline) aluminum complex (Alq
3) was deposited to obtain an electron injection layer having a thickness of 30 nm. An electrode having a thickness of 100 nm was formed thereon using an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL device. The hole injection layer and the light emitting layer were deposited in a vacuum of 10 ^-6 Torr at a substrate temperature of room temperature. This element has a DC voltage of 5
At 120 V, the emission luminance is 120 cd / m ² , and the maximum emission luminance is 4,200
Light emission with a luminous efficiency of 4.6 lm / W at 0 cd / m ² and 5 V was obtained. Next, as a result of a life test in which the device was continuously lit at a current density of 3 mA / cm ² , luminescence of １ ／ or more of the initial luminance was maintained for 10000 hours or more.

Examples 2 to 21 Organic EL devices were prepared in the same manner as in Example 1 except that the compounds shown in Table 3 were used instead of the compound (1) in the light emitting layer. This device exhibited the emission characteristics shown in Table 3.

[0071]

[Table 3]

Example 22 A compound (12) was vacuum-deposited on a washed glass plate with an ITO electrode to form a 100 nm-thick light-emitting layer, and an alloy obtained by mixing magnesium and silver at a ratio of 10: 1 was formed thereon. An electrode having a thickness of 150 nm was formed to obtain an organic EL device. The light emitting layer and the cathode were deposited at a substrate temperature of room temperature in a vacuum of 10 ^-6 Torr. This element has a DC voltage of 5
Luminance 50 cd / m ² at V, maximum luminance 3500 c
Light emission with a luminous efficiency of 0.4 lm / W at d / m ² and 5 V was obtained. Next, at a current density of 3 mA / cm ² , as a result of a life test in which the device was continuously emitted, 1 / l of the initial luminance was obtained.
Two or more light emissions were maintained for 5000 hours or more.

Example 23 TPD was vacuum-deposited on a washed glass plate with an ITO electrode to obtain a hole injection layer having a thickness of 20 nm. Then
N, N '-(4-methylphenyl) -N, N'-(4-
(n-butylphenyl) -phenanthrene-9,10-diamine and compound (1) were deposited at a weight ratio of 100: 1 to form a 40 nm-thick light emitting layer, and Alq3 was deposited,
An electron injection layer having a thickness of 10 nm was obtained. An electrode having a thickness of 100 nm was formed thereon using an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL device. The hole injection layer and the light emitting layer were deposited in a vacuum of 10 ^-6 Torr at a substrate temperature of room temperature. This element has a light emission luminance of 2 with a DC voltage of 5 V.
50 cd / m ² , maximum emission luminance 44000 cd / m ² ,
Light emission with a luminous efficiency of 3.8 lm / W at 5 V was obtained.
Next, as a result of a life test in which the device was continuously lit at a current density of 3 mA / cm ² , luminescence of １ ／ or more of the initial luminance was maintained for 10000 hours or more.

Example 24 4, 4 ′, 4 ″ was placed on a washed glass plate with an ITO electrode.
-Tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine was vacuum deposited to a film thickness of 40
As a result, a hole injection layer having a thickness of nm was obtained. Then, 4,4′-bis [N
-(1-Naphthyl) -N-phenylamino] biphenyl (α-NPD) was vacuum-deposited to obtain a 10-nm-thick second hole injection layer. Further, the compound (1) was vacuum-deposited to form a light-emitting layer having a thickness of 30 nm.
A methyl-8-hydroxyquinolinato) (1-phenolate) gallium complex was vacuum-deposited to form a 30-nm-thick electron injection layer, on which aluminum and lithium were added for 2 hours.
An electrode having a thickness of 150 nm was formed from an alloy mixed at 5: 1 to obtain an organic EL device. The hole injection layer and the light emitting layer are 1
Vapor deposition was performed at a substrate temperature of room temperature in a vacuum of 0 ^-6 Torr. This device has a light emission luminance of 240 (c) at a DC voltage of 5 V.
d / m ² ), maximum emission luminance 54000 (cd / m ² ),
Light emission with a luminous efficiency of 4.8 (lm / W) was obtained.

Examples 25 to 44 Organic EL devices were produced in the same manner as in Example 1 except that the compounds shown in Table 4 were used instead of the compound (1) for the light emitting layer. This device exhibited the emission characteristics shown in Table 4.

[0076]

[Table 4]

Example 45 Compound (3) was placed on a washed glass plate with an ITO electrode.
Alq3, TPD, polycarbonate resin (PC-A)
Was dissolved in tetrahydrofuran at a weight ratio of 3: 2: 3: 8, and a light-emitting layer having a thickness of 100 nm was obtained by spin coating. An electrode having a thickness of 150 nm is formed thereon by using an alloy obtained by mixing magnesium and silver at a ratio of 10: 1.
An element was obtained. This device has a DC voltage of 5 V and a luminance of 20 c.
d / m ² , maximum light emission luminance of 3100 cd / m ² , and light emission with a luminous efficiency of 0.5 lm / W at 5 V were obtained. Then 3m
As a result of a life test in which the device was continuously lit at a current density of A / cm ² , luminescence having 30% or more of the initial luminance was 30%.
It was kept for more than 00 hours.

Example 46 α-NPD was vacuum-deposited on a washed glass plate with an ITO electrode to obtain a hole injection layer having a thickness of 30 nm. Next, a bis (2-methyl-8-hydroxyquinolinato) (1-phenolate) gallium complex as a host material and a compound (1) as a doping material are deposited at a weight ratio of 50: 1, and a film thickness of 30 nm. And a 20 nm-thick electron injection layer of [2- (4-tert-butylphenyl) -5- (biphenyl) -1,3,4-oxadiazole] is obtained by a vacuum evaporation method. Was. An electrode having a thickness of 150 nm was formed thereon using an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL device. The hole injection layer, the light emitting layer, the electron injection layer, and the cathode are each composed of 10 ^-6 To.
Vapor deposition was performed at a substrate temperature of room temperature in a vacuum of rr. This device emitted light with a luminance of 230 cd / m ² at a DC voltage of 5 V, a maximum luminance of 53000 cd / m ² , and a luminous efficiency of 4.6 lm / W at 5 V. Next, 3 mA / cm ²
As a result of a life test in which the device was continuously lit at a current density of, light emission of １ ／ or more of the initial luminance was maintained for 10000 hours or more.

Examples 47 to 57 Organic EL devices were produced in the same manner as in Example 24 except that the compounds shown in Table 5 were used as the host material and the doping material for the light emitting layer. This device exhibited the emission characteristics shown in Table 5.

[0080]

[Table 5]

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

[0082]

According to the present invention, it is possible to obtain an organic EL device having higher luminous efficiency, higher luminance and longer life than the conventional one.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Michiko Tamano 2-3-13 Kyobashi, Chuo-ku, Tokyo Inside Toyo Ink Manufacturing Co., Ltd. (72) Inventor Toshio Enoda 2-3-1 Kyobashi, Chuo-ku, Tokyo No. Toyo Ink Manufacturing Co., Ltd.

Claims (7)

[Claims] 1. An organic electroluminescent device material represented by the following general formula [1]. General formula [1] [In the formula, Q ¹ and Q ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, or a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² and R ^{13 to} R ³² are each independently
Hydrogen atom, halogen atom, cyano group, nitro group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted Represents an arylthio group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkylamino group, or a substituted or unsubstituted arylamino group. X ^{1 to} X
⁴ are independently O, S, C = O, C≡C, CZ
_{^{1 = CZ 2, SO 2,}} (CH 2) x-O- (CH 2)
y represents a substituted or unsubstituted alkylene group or a substituted or unsubstituted aliphatic ring residue. Where Z ¹ and Z ²
Each independently represents a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, and x and y are
Each represents a positive integer of 0 to 20, but does not satisfy x + y = 0. R ^{1 to} R ¹² or R ^{13 to} R ³² may be bonded by adjacent groups to form a new ring. ] 2. An organic electroluminescent device material represented by the following general formula [2]. General formula [2] [Wherein, Q ¹ and Q ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, or And a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² and R ^{13 to} R ³² each independently represent a hydrogen atom, a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted Aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted arylthio group, substituted or unsubstituted monocyclic group, substituted or unsubstituted fused polycyclic group, substituted or unsubstituted amino group, substituted or unsubstituted Represents a substituted alkylamino group or a substituted or unsubstituted arylamino group. X ^{1 to} X ⁴ are each independently O, S, C = O,
C≡C, CZ ¹ = CZ ² , SO ₂ , (CH ₂ ) x—O—
(CH ₂ ) y represents a substituted or unsubstituted alkylene group or a substituted or unsubstituted aliphatic ring residue. Where Z ¹
And Z ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, and x and y each represent 0 Represents a positive integer of ２０20, but x +
y = 0 never occurs. R ^{1 to} R ¹² or R ¹³ to
R ³² may combine with adjacent groups to form a new ring. ] 3. An organic electroluminescent device material represented by the following general formula [3]. General formula [3] [In the formula, Q ¹ and Q ² each independently represent a hydrogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted monocyclic group, or a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² and R ^{13 to} R ³² are each independently
Hydrogen atom, halogen atom, cyano group, nitro group, substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted aryloxy group, substituted or unsubstituted alkylthio group, substituted or unsubstituted Represents an arylthio group, a substituted or unsubstituted monocyclic group, a substituted or unsubstituted fused polycyclic group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkylamino group, or a substituted or unsubstituted arylamino group. Y ^{1 to} Y
⁸ represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted monocyclic group having 6 to 16 carbon atoms, or a substituted or unsubstituted fused polycyclic group. R ^{1 to} R ¹² or R ^{13 to} R ³² may be bonded by adjacent groups to form a new ring. ] 4. An organic electroluminescent device having a plurality of organic compound thin films including a light emitting layer formed between a pair of electrodes, wherein the light emitting layer contains the organic electroluminescent device material according to claim 1. An organic electroluminescence device. 5. A light emitting layer comprising a host material and a doping material, wherein the doping material is the organic electroluminescence device material according to claim 1.
The organic electroluminescent device according to the above. 6. The organic electroluminescent device according to claim 4, wherein one to four electron injection layers and electron transport layers are formed between the light emitting layer and the cathode. 7. The organic electroluminescent device according to claim 4, wherein 1 to 4 hole injection layers and hole transport layers are formed between the light emitting layer and the anode.