JP2009173565A - Material for organic electroluminescent element and organic electroluminescent element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a material for an organic electroluminescent element, exhibiting excellent characteristics such as high brightness, high efficiency, low voltage drive, long life and heat resistance, and to provide the organic electroluminescent element using the material. <P>SOLUTION: The material for the organic electroluminescent element is a compound represented by general formula [1], wherein R<SP>1</SP>and R<SP>2</SP>are each independently a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group or a substituted or unsubstituted monovalent aromatic heterocyclic group. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a material for an organic electroluminescence element used for a planar light source and display, and an organic electroluminescence element using the same.

  Recent advances in organic electroluminescence devices are remarkable, and their features are high brightness, diversity of emission wavelengths, high-speed response, thinness, and light-emitting devices with low applied voltage, making them suitable for a wide range of applications. Suggests the possibility.

  However, under the present circumstances, light output with higher brightness or higher conversion efficiency is required. In addition, there are still many problems in terms of durability, such as changes over time due to long-term use and deterioration due to atmospheric gas or moisture containing oxygen. Furthermore, blue, green, and red light emission with high color purity is required when considering application to a full color display or the like, but these problems are still not sufficient.

  In particular, with respect to blue light emitting elements, there are few blue light emitting materials that provide elements with excellent durability. As an example, a technique using an anthracene compound for a blue light emitting element is disclosed. Blue light emitting devices using various anthracene compounds (Patent Documents 1 to 4) have been reported, but all have insufficient durability against heat and oxygen.

As the application of the bithiazole compound to organic electroluminescence, a structure in which a nitrogen atom is introduced at the 2-position of the thiazole ring has already been disclosed (Non-patent Document 1). However, there is no disclosure regarding a bithiazole compound having a structure in which a nitrogen atom is introduced at the 5-position of the thiazole ring.
In addition, the application of 5,5′-bithiazole derivatives to organic semiconductor materials has been studied so far. (Non-patent document 2) However, the performance as a light-emitting material for an organic electroluminescence element was completely unknown.

Synthetic Metals, 121, 1689, 2001 Journal of American Chemical Society, 127, 5336, published in 2005 JP 2003-306454 A Japanese Patent Laid-Open No. 2004-2351 WO2005 / 113531 JP 2007-63501 A

  The subject of this invention is providing the organic electroluminescent element material which shows the outstanding characteristics, such as high brightness | luminance, high efficiency, low voltage drive, long life, and heat resistance, and an organic electroluminescent element using the same. .

  As a result of intensive studies to solve the above problems, the present inventors have arrived at the present invention.

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

General formula [1]

Wherein R ¹ and R ² are each independently a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted Represents a monovalent aromatic heterocyclic group.)

In the present invention, R ¹ and R ² are each independently a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted carbon atom having 3 to 18 carbon atoms. The present invention relates to the material for an organic electroluminescence device, which is a monovalent aromatic heterocyclic group.

In the present invention, R ¹ and R ² are each independently a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted carbon atom having 6 to 18 carbon atoms. The present invention relates to the material for an organic electroluminescence device, which is a monovalent aromatic heterocyclic group.

In the present invention, R ¹ and R ² are each independently an unsubstituted monovalent aromatic hydrocarbon group or an unsubstituted monovalent aromatic heterocyclic group. The present invention relates to a material for an organic electroluminescence element.
Further, the present invention provides an organic electroluminescence device comprising a plurality of organic layers including a light emitting layer between a pair of electrodes, wherein at least one of the organic layers comprises the material for an organic electroluminescence device. The present invention relates to an organic electroluminescence element.

  In addition, the present invention provides an organic electroluminescent device in which a light emitting layer or a plurality of organic layers including a light emitting layer is formed between a pair of electrodes, wherein the light emitting layer includes the organic electroluminescent device material. The present invention relates to an electroluminescence element.

  The present invention also relates to a compound represented by the following general formula [1].

General formula [1]

Wherein R ¹ and R ² are each independently a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted Represents a monovalent aromatic heterocyclic group.)

  Since the compound represented by the general formula [1] of the present invention exhibits strong light emission, it is useful as a light-emitting material to be contained in the light-emitting layer of the organic electroluminescence device, and of course, the light-emitting layer host in organic electroluminescence. It is also useful as a material, a light emitting layer dopant material, and an electron injection material, and can also be used as a fluorescent indicator for detecting trace components by utilizing its light emission characteristics. Organic electroluminescent elements using these organic electroluminescent element materials can be suitably used as flat panel displays such as wall-mounted televisions and flat light emitters because they are driven at a low voltage and have a long lifetime. It can be applied to light sources such as copiers and printers, light sources such as liquid crystal displays and instruments, display boards, and indicator lights.

  Hereinafter, the present invention will be described in detail.

First, R ¹ and R ² in the general formula [1] are each independently a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or substituted or unsubstituted It represents an unsubstituted monovalent aromatic heterocyclic group.

  Here, examples of the monovalent aliphatic hydrocarbon group include an alkyl group, an alkenyl group, an alkynyl group, and a cycloalkyl group.

  Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, Examples include a decyl group, a dodecyl group, a pentadecyl group, and an octadecyl group, and an alkyl group having 1 to 18 carbon atoms is preferable.

  Examples of the alkenyl group include vinyl group, 1-propenyl group, 2-propenyl group, isopropenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1-octenyl group, 1-decenyl group, 1 -Groups such as an octadecenyl group are exemplified, and an alkenyl group having 2 to 18 carbon atoms is preferred.

  Examples of the alkynyl group include ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-butynyl group, 1-octynyl group, 1-decynyl group and 1-octadecynyl group. Group, preferably an alkynyl group having 2 to 18 carbon atoms.

  Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclooctadecyl group, and preferably a cycloalkyl group having 3 to 18 carbon atoms. It is.

  Furthermore, examples of the monovalent aromatic hydrocarbon group include a monovalent monocyclic ring, a condensed ring, and a ring assembly hydrocarbon group. Here, examples of the monovalent monocyclic aromatic hydrocarbon group include groups such as phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 2,4-xylyl group, p-cumenyl group, and mesityl group. Preferably, it is a C6-C18 monocyclic aromatic hydrocarbon group.

  Examples of the monovalent condensed ring hydrocarbon group include 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 5-anthryl group, 1-phenanthryl group, 9-phenanthryl group, 1- Examples include acenaphthyl group, 2-azurenyl group, 1-pyrenyl group, and 2-triphenylyl group, and a monocyclic aromatic hydrocarbon group having 10 to 18 carbon atoms is preferable.

  Examples of the monovalent ring assembly hydrocarbon group include groups such as an o-biphenylyl group, an m-biphenylyl group, and a p-biphenylyl group, and preferably a monocyclic aromatic hydrocarbon group having 12 to 18 carbon atoms. .

  The monovalent aromatic hydrocarbon is preferably a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms.

  Examples of the monovalent aromatic heterocyclic group include triazolyl group, 3-oxadiazolyl group, 2-furanyl group, 3-furanyl group, 2-furyl group, 3-furyl group, 2-thienyl group and 3-thienyl group. 1-pyrrolyl group, 2-pyrrolyl group, 3-pyrrolyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, 2-pyrazyl group, 2-oxazolyl group, 3-isoxazolyl Group, 2-thiazolyl group, 3-isothiazolyl group, 2-imidazolyl group, 3-pyrazolyl group, 2-quinolyl group, 3-quinolyl group, 4-quinolyl group, 5-quinolyl group, 6-quinolyl group, 7-quinolyl group Group, 8-quinolyl group, 1-isoquinolyl group, 2-quinoxalinyl group, 2-benzofuryl group, 2-benzothienyl group, N-indolyl group, N-carbazolyl group, N-acridinyl group, 2- Ofeniru group, 3-thiophenyl group, a bipyridyl group, include groups such phenanthrolyl group, preferably a monovalent aromatic heterocyclic group having 2 to 18 carbon atoms.

The monovalent aliphatic hydrocarbon group, monovalent aromatic hydrocarbon group, and monovalent aromatic heterocyclic group in R ¹ and R ² may be further substituted with other substituents. Examples of the substituent which may be further substituted include a halogen atom and a monovalent organic residue.

  Here, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among these, preferred are a fluorine atom and a chlorine atom, and particularly preferred is a fluorine atom.

  The monovalent organic residue is not particularly limited, but may be a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted or unsubstituted 1 Valent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxy group, aryloxy group, alkylthio group, arylthio group, substituted amino group, acyl group, alkoxycarbonyl group, aryl Examples thereof include an oxycarbonyl group, an alkylsulfonyl group, and an arylsulfonyl group.

Here, examples of the monovalent aliphatic hydrocarbon group, monovalent aromatic hydrocarbon group, and monovalent aromatic heterocyclic group include those described above.
Examples of the monovalent aliphatic heterocyclic group include a 2-pyrazolino group, a piperidino group, a morpholino group, and a 2-morpholino group, and preferably a monovalent aliphatic heterocyclic group having 3 to 18 carbon atoms. .

  Moreover, as an alkoxy group, C1-C8 alkoxyl groups, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a tert-butoxy group, an octyloxy group, a tert-octyloxy group, are mentioned.

  The aryloxy group includes aryloxy groups having 6 to 14 carbon atoms such as phenoxy group, 4-tert-butylphenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, and 9-anthryloxy group. Can be mentioned.

  Moreover, as an alkylthio group, a C1-C8 alkylthio group, such as a methylthio group, an ethylthio group, a tert- butylthio group, a hexylthio group, and an octylthio group, is mentioned.

  Examples of the arylthio group include arylthio groups having 6 to 14 carbon atoms such as a phenylthio group, a 2-methylphenylthio group, and a 4-tert-butylphenylthio group.

  The substituted amino group includes N-methylamino group, N-ethylamino group, N, N-diethylamino group, N, N-diisopropylamino group, N, N-dibutylamino group, N-benzylamino group, N , N-dibenzylamino group, N-phenylamino group, N-phenyl-N-methylamino group, N, N-diphenylamino group, N, N-bis (m-tolyl) amino group, N, N-bis (P-tolyl) amino group, N, N-bis (p-biphenylyl) amino group, bis [4- (4-methyl) biphenylyl] amino group, N-α-naphthyl-N-phenylamino group, N-β -Substituted amino groups having 2 to 26 carbon atoms such as naphthyl-N-phenylamino group.

  Moreover, as an acyl group, C2-C14 acyl groups, such as an acetyl group, a propionyl group, a pivaloyl group, a cyclohexyl carbonyl group, a benzoyl group, a toluoyl group, an anisoyl group, a cinnamoyl group, are mentioned.

  Moreover, as an alkoxycarbonyl group, C2-C14 alkoxycarbonyl groups, such as a methoxycarbonyl group, an ethoxycarbonyl group, a benzyloxycarbonyl group, are mentioned.

  Examples of the aryloxycarbonyl group include aryloxycarbonyl groups having 2 to 14 carbon atoms such as phenoxycarbonyl group and naphthyloxycarbonyl group.

  Moreover, as an alkylsulfonyl group, C2-C14 alkylsulfonyl groups, such as a mesyl group, an ethylsulfonyl group, a propylsulfonyl group, are mentioned.

  Moreover, as an arylsulfonyl group, C2-C14 arylsulfonyl groups, such as a benzenesulfonyl group and p-toluenesulfonyl group, are mentioned.

What is preferable as R ¹ and R ² in the general formula [1] is a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms or a monovalent aromatic heterocyclic group having 3 to 18 carbon atoms, and more A monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms or a monovalent aromatic heterocyclic group having 6 to 18 carbon atoms is preferable. As mentioned above, these may have a halogen atom or a monovalent organic residue as a substituent.

More preferable examples of R ¹ and R ² in the general formula [1] include an unsubstituted monovalent aromatic hydrocarbon group or an unsubstituted monovalent aromatic heterocyclic group, and are particularly preferable. The thing includes an unsubstituted monovalent aromatic heterocyclic group.

    Typical examples of the compound represented by the general formula [1] that can be used for the organic electroluminescence device material of the present invention are shown in the following Table 1. However, the present invention is not limited to these representative examples. Absent.

      Table 1

  The compound group represented by the general formula [1] can be obtained by a known method. For example, a 5-bromo-2-thiazole derivative in a tetrahydrofuran solvent is mixed with n-butyllithium and tris (2,4-pentane. Dionate) can be obtained by reacting with iron (III).

  The material for an organic electroluminescence device is required to have a high purity material, but the material for an organic electroluminescence device of the present invention is a sublimation purification method, a recrystallization method, a reprecipitation method, a zone melting method, a column purification method, An adsorption method or a combination of these methods can be used. Of these purification methods, the recrystallization method is preferred. For compounds having sublimation properties, it is preferable to employ a sublimation purification method. In the sublimation purification, it is preferable to employ a method in which the sublimation boat is maintained at a temperature lower than the temperature at which the target compound sublimates, and the sublimation impurities are removed in advance. In addition, it is desirable to apply a temperature gradient to the portion where the sublimate is collected so that the sublimate is dispersed in the impurities and the target product. Sublimation purification as described above is purification that separates impurities, and can be applied to the present invention. In addition, sublimation purification is useful for predicting the difficulty of the material vapor deposition.

  Here, the organic electroluminescent element which can be produced using the organic electroluminescent element material of the present invention will be described in detail.

  An organic electroluminescent element is composed of an element in which a single layer or a multilayer organic layer is formed between an anode and a cathode. Here, a single layer type organic electroluminescent element is composed of only a light emitting layer between an anode and a cathode. The element which becomes. On the other hand, a multi-layer organic electroluminescent element is one that facilitates the injection of holes and electrons into the light emitting layer in addition to the light emitting layer, and facilitates recombination of holes and electrons in the light emitting layer. For example, a layer in which a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, and the like are stacked is used. Therefore, typical device configurations of the multilayer organic electroluminescence device include (1) anode / hole injection layer / light emitting layer / cathode, and (2) anode / hole injection layer / hole transport layer / light emitting layer / Cathode, (3) anode / hole injection layer / light emitting layer / electron injection layer / cathode, (4) anode / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode, (5) anode / Hole injection layer / light emitting layer / hole blocking layer / electron injection layer / cathode, (6) anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron injection layer / cathode, (7 An element configuration in which a multilayer structure such as () anode / light emitting layer / hole blocking layer / electron injection layer / cathode, (8) anode / light emitting layer / electron injection layer / cathode is considered.

  Moreover, each organic layer mentioned above may be formed by the layer structure of two or more layers, respectively, and several layers may be laminated | stacked repeatedly. As such an example, in recent years, for the purpose of improving the light extraction efficiency, an element configuration called “multi-photon emission” in which some layers of the above-described multilayer organic electroluminescence element are multilayered has been proposed. . For example, in an organic electroluminescence device composed of a glass substrate / anode / hole transport layer / electron transporting light emitting layer / electron injection layer / charge generating layer / light emitting unit / cathode, a charge generating layer and a light emitting unit The method of laminating | stacking two or more layers of this part is mentioned.

  If necessary, in addition to the organic electroluminescence device material of the present invention, further known light emitting materials, doping materials, hole injection materials and electron injection materials can be used for the light emitting layer. Depending on the type and composition of the material used, it is possible to improve emission luminance and emission efficiency, and to obtain various emission colors such as red, blue, and green. In addition, white light emission can be obtained by combining a plurality of light emitting materials.

  Examples of the light emitting material or doping material that can be used in the light emitting layer together with the organic electroluminescent device material of the present invention include anthracene derivatives, naphthalene derivatives, phenanthrene derivatives, pyrene derivatives, tetracene derivatives, coronene derivatives, chrysene derivatives, fluorescein derivatives, perylene derivatives, Phthaloperylene derivatives, naphthaloperylene derivatives, perinone derivatives, phthaloperinone derivatives, naphthaloperinone derivatives, diphenylbutadiene derivatives, tetraphenylbutadiene derivatives, coumarin derivatives, oxadiazole derivatives, aldazine derivatives, bisbenzoxazoline derivatives, bisstyryl derivatives, diketopyrrolopyrrole derivatives, Pyrazine derivatives, cyclopentadiene derivatives, quinoline metal complex derivatives, diphenylethylene derivatives, biphenyl Luanthracene derivatives, carbazole derivatives, pyran derivatives, thiopyran derivatives, polymethine derivatives, merocyanine derivatives, imidazole chelating oxinoid compounds, quinacridone derivatives, rubrene derivatives, fluorescent dyes for dye lasers and whitening, etc. Is not to be done.

  Among the above materials, the light emitting layer constituting material that can be suitably used includes naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, pyrene derivatives, tetracene derivatives, perylene derivatives, carbazole derivatives, benzothiophene derivatives, benzofuran derivatives, benzoxazole derivatives, Examples thereof include benzothiazole derivatives, biphenyl derivatives, diketopyrrolopyrrole derivatives, and quinoline metal complexes.

  In addition, the light-emitting layer includes insulating resins such as polystyrene, polycarbonate, polyacrylate, polyester, polyamide, polyurethane, polysulfone, polymethyl methacrylate, polymethyl acrylate, and cellulose, and copolymers thereof, poly-N-vinylcarbazole. To the polymer such as photoconductive resin such as polysilane, conductive resin such as polythiophene and polypyrrole, the material of the present invention and the above light emitting layer constituting material, film formation improvement, film pinhole prevention, etc. What mixed antioxidant, a ultraviolet absorber, a plasticizer, etc. can also be used.

  Any of the organic electroluminescence device material of the present invention and the above-mentioned compound that can be used in the light emitting layer in the light emitting layer may be the main component. That is, depending on the combination of the above compound and the material for an organic electroluminescence device of the present invention, the compound of the present invention can be a main material for forming a light emitting layer or a dopink material in another main material.

For the hole injection layer, a hole injection material that exhibits an excellent hole injection effect with respect to the light emitting layer and that can form a hole injection layer excellent in adhesion to the anode interface and thin film formability is used. In addition, when such materials are laminated in multiple layers and a material having a high hole injection effect and a material having a high hole transport effect are laminated, the materials used for each are called a hole injection material and a hole transport material. Sometimes. The organic electroluminescent element material of the present invention can be suitably used for both hole injection materials and hole transport materials. These hole injection materials and hole transport materials need to have a high hole mobility and a small ionization energy of usually 5.5 eV or less. Such a hole injection layer is preferably a material that transports holes to the light emitting layer with a lower electric field strength, and further has a hole mobility of at least when an electric field of 10 ⁴ to 10 ⁶ V / cm is applied. What is 10 ^<-6 > cm ^{< 2} > / V * second is preferable. Other hole injection materials and hole transport materials that can be used by mixing with the organic electroluminescence device material of the present invention are not particularly limited as long as they have the above-mentioned preferable properties. Any one of those commonly used as hole charge transport materials in photoconductive materials and known materials used in hole injection layers of organic electroluminescent elements can be selected and used.

  Specific examples of such hole injection materials and hole transport materials include triazole derivatives (see US Pat. No. 3,112,197) and oxadiazole derivatives (US Pat. No. 3,189,447). Imidazole derivatives (see Japanese Patent Publication No. 37-16096), polyarylalkane derivatives (US Pat. Nos. 3,615,402, 3,820,989, 3,542,544, JP-B-45-555, JP-A-51-10983, JP-A-51-93224, JP-A-55-17105, JP-A-56-4148, JP-A-55- No. 108667, No. 55-156953, No. 56-36656, etc.), pyrazoline derivatives and pyrazolone derivatives (US Pat. No. 3,180, No. 29, No. 4,278,746, JP-A 55-88064, No. 55-88065, No. 49-105537, No. 55-51086, No. 56-80051. No. 56-88141, No. 57-45545, No. 54-112437, No. 55-74546, etc.), phenylenediamine derivatives (US Pat. No. 3,615,404, Japanese Patent Publication Nos. 51-10105, 46-3712, 47-25336, JP 54-53435, 54-110536, 54-1119925, etc.), arylamine Derivatives (US Pat. Nos. 3,567,450, 3,180,703, 3,240,597, 3 No. 658,520, No. 4,232,103, No. 4,175,961, No. 4,012,376, JP-B 49-35702, No. 39 -27577, JP-A-55-144250, JP-A-56-119132, JP-A-56-22437, West German Patent No. 1,110,518, etc.), amino-substituted chalcone derivatives (US patents) No. 3,526,501), oxazole derivatives (disclosed in US Pat. No. 3,257,203, etc.), styryl anthracene derivatives (see JP 56-46234 A, etc.), Fluorenone derivatives (see JP-A-54-110837, etc.), hydrazone derivatives (US Pat. No. 3,717,462, JP-A-54-59143, 55-52063, 55-52064, 55-46760, 55-85495, 57-11350, 57-148749, JP-A-2-311591, etc. Stilbene derivatives (Japanese Patent Laid-Open Nos. 61-210363, 61-228451, 61-14642, 61-72255, 62-47646, 62-36674) 62-10652, 62-30255, 60-93455, 60-94462, 60-174749, 60-175052, etc.), silazane derivatives (US) Patent No. 4,950,950), polysilane (JP-A-2-204996), aniline copolymer (JP-A-2-282263), an electroconductive oligomer (particularly a thiophene oligomer) disclosed in JP-A-1-211399 and the like.

  As the hole injecting material and the hole transporting material, those described above can be used. Porphyrin compounds (Japanese Patent Laid-Open No. 63-295965), aromatic tertiary amine compounds and styrylamine compounds (US Pat. No. 4,127,412, JP-A-53-27033, 54-58445, 54-149634, 54-64299, 55-79450, 55-144250 No. 56-119132, No. 61-295558, No. 61-98353, No. 63-295695, etc.) can also be used. For example, 4,4′-bis (N- (1-naphthyl) -N-phenylamino) biphenyl having two condensed aromatic rings in the molecule described in US Pat. No. 5,061,569, etc. And 4,4 ′, 4 ″ -tris (N- (3-methylphenyl) -N-phenyl, in which three triphenylamine units described in JP-A-4-308688 are linked in a starburst type. Amino) triphenylamine, etc. In addition, examples of the hole injection material include phthalocyanine derivatives such as copper phthalocyanine and hydrogen phthalocyanine, and other aromatic dimethylidene compounds, p-type Si, p-type SiC, etc. These inorganic compounds can also be used as hole injection materials and hole transport materials.

Specific examples of the aromatic tertiary amine derivative include, for example, N, N′-diphenyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N , N ′, N ′-(4-methylphenyl) -1,1′-phenyl-4,4′-diamine, N, N, N ′, N ′-(4-methylphenyl) -1,1′- Biphenyl-4,4′-diamine, N, N′-diphenyl-N, N′-dinaphthyl-1,1′-biphenyl-4,4′-diamine, N, N ′-(methylphenyl) -N, N '-(4-n-Butylphenyl) -phenanthrene-9,10-diamine, N, N-bis (4-di-4-tolylaminophenyl) -4-phenyl-cyclohexane, N, N'-bis (4 '-Diphenylamino-4-biphenylyl) -N, N'-diphenylbenzidine, N, N'-bis (4 '-Diphenylamino-4-phenyl) -N, N'-diphenylbenzidine, N, N'-bis (4'-diphenylamino-4-phenyl) -N, N'-di (1-naphthyl) benzidine, N , N′-bis (4′-phenyl (1-naphthyl) amino-4-phenyl) -N, N′-diphenylbenzidine, N, N′-bis (4′-phenyl (1-naphthyl) amino-4- Phenyl) -N, N′-di (1-naphthyl) benzidine and the like, and these can be used for both hole injection materials and hole transport materials.
Particularly preferred examples of the hole injection material are shown in Table 2.

Table 2

  Moreover, as a hole transport material which can be used with the organic electroluminescent element material of this invention, the compound shown in following Table 3 is also mentioned.

Table 3

  In order to form the hole injection layer described above, the above-mentioned compound is thinned by a known method such as a vacuum deposition method, a spin coating method, a casting method, or an LB method. The thickness of the hole injection layer is not particularly limited, but is usually 5 nm to 5 μm.

  On the other hand, for the electron injection layer, an electron injection material that exhibits an excellent electron injection effect with respect to the light emitting layer and that can form an electron injection layer excellent in adhesion to the cathode interface and thin film formability is used. Examples of such electron injection materials include metal complex compounds, nitrogen-containing five-membered ring derivatives, fluorenone derivatives, anthraquinodimethane derivatives, diphenoquinone derivatives, thiopyrandioxide derivatives, perylenetetracarboxylic acid derivatives, fluorenylidenemethane. Derivatives, anthrone derivatives, silole derivatives, triarylphosphine oxide derivatives, calcium acetylacetonate, sodium acetate and the like. In addition, inorganic / organic composite materials doped with metal such as cesium in bathophenanthroline (Proceedings of the Society of Polymer Science, Vol. 50, No. 4, 660, published in 2001), and the 50th Applied Physics Related Lecture Lecture Proceedings, No. Examples of electron injection materials include BCP, TPP, T5MPyTZ, etc., published on page 3, 1402, 2003. However, a thin film necessary for device fabrication can be formed, electrons from the cathode can be injected, and electrons can be transported. If it is material, it will not specifically limit to these.

  Preferable examples of the electron injection material include metal complex compounds, nitrogen-containing five-membered ring derivatives, silole derivatives, and triarylphosphine oxide derivatives. As a preferable metal complex compound that can be used in the present invention, a metal complex of 8-hydroxyquinoline or a derivative thereof is suitable. Specific examples of the metal complex of 8-hydroxyquinoline or a derivative thereof include tris (8-hydroxyquinolinate) aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (4-methyl-8- Hydroxyquinolinato) aluminum, tris (5-methyl-8-hydroxyquinolinato) aluminum, tris (5-phenyl-8-hydroxyquinolinato) aluminum, bis (8-hydroxyquinolinato) (1-naphtholate) ) Aluminum, bis (8-hydroxyquinolinate) (2-naphtholate) aluminum, bis (8-hydroxyquinolinate) (phenolate) aluminum, bis (8-hydroxyquinolinato) (4-cyano-1-naphtholate) ) Aluminum, bis (4-methyl-8) Hydroxyquinolinato) (1-naphtholato) aluminum, bis (5-methyl-8-hydroxyquinolinato) (2-naphtholato) aluminum, bis (5-phenyl-8-hydroxyquinolinato) (phenolate) aluminum, Bis (5-cyano-8-hydroxyquinolinate) (4-cyano-1-naphtholato) aluminum, bis (8-hydroxyquinolinato) chloroaluminum, bis (8-hydroxyquinolinato) (o-cresolate) Aluminum complex compounds such as aluminum, tris (8-hydroxyquinolinato) gallium, tris (2-methyl-8-hydroxyquinolinato) gallium, tris (4-methyl-8-hydroxyquinolinato) gallium, tris ( 5-Methyl-8-hydroxyquinolinate Gallium, tris (2-methyl-5-phenyl-8-hydroxyquinolinato) gallium, bis (2-methyl-8-hydroxyquinolinato) (1-naphtholato) gallium, bis (2-methyl-8-hydroxy) Quinolinate) (2-naphtholato) gallium, bis (2-methyl-8-hydroxyquinolinato) (phenolate) gallium, bis (2-methyl-8-hydroxyquinolinato) (4-cyano-1-naphtholate) ) Gallium, bis (2,4-dimethyl-8-hydroxyquinolinato) (1-naphtholate) gallium, bis (2,5-dimethyl-8-hydroxyquinolinato) (2-naphtholato) gallium, bis (2 -Methyl-5-phenyl-8-hydroxyquinolinate) (phenolate) gallium, bis (2-methyl-5- Cyano-8-hydroxyquinolinate) (4-cyano-1-naphtholate) gallium, bis (2-methyl-8-hydroxyquinolinate) chlorogallium, bis (2-methyl-8-hydroxyquinolinate) ( In addition to gallium complex compounds such as o-cresolate) gallium, 8-hydroxyquinolinate lithium, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, bis (10-hydroxybenzo [h ] Quinolinato) metal complex compounds such as beryllium, bis (8-hydroxyquinolinato) zinc, bis (10-hydroxybenzo [h] quinolinato) zinc.

  Among the electron injection materials that can be used in the present invention, preferable nitrogen-containing five-membered ring derivatives include oxazole derivatives, thiazole derivatives, oxadiazole derivatives, thiadiazole derivatives, and triazole derivatives. , 5-bis (1-phenyl) -1,3,4-oxazole, 2,5-bis (1-phenyl) -1,3,4-thiazole, 2,5-bis (1-phenyl) -1, 3,4-oxadiazole, 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) 1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1 , 3,4-oxadiazole, 1,4-bis [2- (5-phenyloxadiazolyl)] benzene, 1,4-bis [2- (5-phenyloxadiazolyl) -4-tert-butyl benzene], 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-thiadiazole, 2,5-bis (1-naphthyl) -1,3,4-thiadiazole, 1, 4-bis [2- (5-phenylthiadiazolyl)] benzene, 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-triazole, 2,5- Bis (1-naphthyl) -1,3,4-triazole, 1,4-bis [2- (5-phenyltriazolyl)] benzene and the like can be mentioned.

  Specific examples of particularly preferred oxadiazole derivatives among the electron injection materials that can be used in the present invention are shown in Table 4.

  Table 4

  Specific examples of particularly preferred triazole derivatives among the electron injection materials that can be used in the present invention are shown in Table 5. In Table 5, Ph represents a phenyl group.

Table 5

  Specific examples of particularly preferred silole derivatives among the electron injection materials that can be used in the present invention are shown in Table 6.

  Table 6

  Furthermore, a hole blocking material that can prevent holes from passing through the light emitting layer from reaching the electron injection layer and form a layer having excellent thin film formability is used for the hole blocking layer. Examples of such hole blocking materials include aluminum complex compounds such as bis (8-hydroxyquinolinate) (4-phenylphenolate) aluminum, and bis (2-methyl-8-hydroxyquinolinate) ( Examples include gallium complex compounds such as 4-phenylphenolate) gallium and nitrogen-containing condensed aromatic compounds such as 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP).

As the light emitting layer of the organic electroluminescence device of the present invention, those having the following functions are suitable.
Injection function; function transport function that can inject holes from the anode or hole injection layer when an electric field is applied, and electrons from the cathode or electron injection layer; electric field of injected charges (electrons and holes) Light emitting function: A function that provides a field for recombination of electrons and holes and connects it to light emission. However, there is a difference between the ease of hole injection and the ease of electron injection. In addition, the transport ability represented by the mobility of holes and electrons may be large or small.

  The material for an organic electroluminescence element of the present invention can be suitably used as a light emitting layer. The organic electroluminescence device material of the present invention can be used as a host material or a dopant material in a light emitting layer, and can be combined with other compounds to form a light emitting layer. In particular, a dopant material for producing a blue light emitting device. Can be suitably used.

  Fluorescent brighteners such as benzothiazole, benzimidazole, and benzoxazole, metal chelated oxinoid compounds, styrylbenzene, in order to obtain blue to green light emission by using the organic electroluminescent device material of the present invention Compounds can be used. Specific examples of these compounds include compounds disclosed in, for example, JP-A-59-194393. Still other useful compounds are listed in Chemistry of Synthetic Soybean (1971) pages 628-637 and 640.

  As the metal chelated oxinoid compound, for example, compounds disclosed in JP-A-63-295695 can be used. As typical examples, 8-hydroxyquinoline metal complexes such as tris (8-quinolinol) aluminum, dilithium epinetridione and the like can be mentioned as suitable compounds.

  As the styrylbenzene compound, for example, those disclosed in European Patent No. 0319881 and European Patent No. 0373582 can be used. And the distyrylpyrazine derivative currently disclosed by Unexamined-Japanese-Patent No. 2-252793 can also be used as a material of a light emitting layer. In addition, polyphenyl compounds disclosed in EP 0387715 can also be used as a material for the light emitting layer.

  Further, in addition to the above-described fluorescent brightener, metal chelated oxinoid compound, styrylbenzene compound and the like, for example, 12-phthaloperinone (J. Appl. Phys., Vol. 27, L713 (1988)), 1,4- Diphenyl-1,3-butadiene, 1,1,4,4-tetraphenyl-1,3-butadiene (Appl. Phys. Lett., Vol. 56, L799 (1990)), naphthalimide derivatives No. 2-305886), perylene derivatives (Japanese Patent Laid-Open No. 2-189890), oxadiazole derivatives (Japanese Patent Laid-Open No. Hei 2-216791, or the 38th Applied Physics Related Conference) were disclosed by Hamada et al. Oxadiazole derivatives), aldazine derivatives (JP-A-2-220393), pyrazirine Conductor (JP-A-2-220394), cyclopentadiene derivative (JP-A-2-289675), pyrrolopyrrole derivative (JP-A-2-29691), styrylamine derivative (Appl. Phys. Lett., 56th) Vol. L799 (1990), coumarin compounds (Japanese Patent Laid-Open No. 2-191694), International Patent Publications WO 90/13148 and Appl. Phys. Lett., Vol 58, 18, P1982 (1991). Polymer compounds, 9,9 ′, 10,10′-tetraphenyl-2,2′-bianthracene, PPV (polyparaphenylene vinylene) derivatives, polyfluorene derivatives and copolymers thereof, for example, the following general formula [ 3] to those having the structure of the general formula [5].

General formula [3]

(In the formula, R ^x1 and R ^X2 each independently represent a monovalent aliphatic hydrocarbon group, and n1 represents an integer of 3 to 100.)

General formula [4]

(In the formula, R ^x3 and R ^X4 each independently represent a monovalent aliphatic hydrocarbon group, and n2 and n3 each independently represent an integer of 3 to 100.)

General formula [5]

(In the formula, R ^X5 and R ^X6 each independently represent a monovalent aliphatic hydrocarbon group, n4 and n5 each independently represent an integer of 3 to 100, and Ph represents a phenyl group.)

In addition, the general formula (Rs-Q) _2- Al-O-L3 (wherein L3 is a hydrocarbon having 6 to 24 carbon atoms including a phenyl moiety) described in JP-A-5-258862, etc. O-L3 is a phenolate ligand, Q represents a substituted 8-quinolinolato ligand, Rs sterically represents that two or more substituted 8-quinolinolato ligands are bonded to an aluminum atom. And a bis (2-methyl-8-quinolinolato) (para-phenylphenolato) aluminum (III) compound, which represents an 8-quinolinolato ring substituent selected to interfere. ), Bis (2-methyl-8-quinolinolato) (1-naphtholato) aluminum (III) and the like.

Although there is no restriction | limiting in particular as a light emitting layer in the case of obtaining white light emission, The following can be used.
The energy level of each layer of the organic electroluminescence laminated structure is defined and light is emitted using tunnel injection (European Patent No. 0390551).
Similarly, a white light emitting element is described as an example of an element using tunnel injection (Japanese Patent Laid-Open No. 3-230584).
A light-emitting layer having a two-layer structure is described (JP-A-2-220390 and JP-A-2-216790).
A structure in which a light emitting layer is divided into a plurality of materials each having a different emission wavelength (Japanese Patent Laid-Open No. 4-51491).
A structure in which a blue phosphor (fluorescence peak 380 to 480 nm) and a green phosphor (480 to 580 nm) are stacked and a red phosphor is further contained (Japanese Patent Laid-Open No. 6-207170).
The blue light emitting layer contains a blue fluorescent dye, the green light emitting layer has a region containing a red fluorescent dye, and further contains a green phosphor (Japanese Patent Laid-Open No. 7-142169).
Among these, those having the above-described configuration are particularly preferable.

  Moreover, in the organic electroluminescent element of this invention, a phosphorescence-emitting material can also be used. In this case, the compound of the present invention can be used as a host material in the light emitting layer. The phosphorescent light-emitting material here means a compound that emits light when transitioning from an excited triplet state to a ground state. Examples of phosphorescent materials that can be used in the organic electroluminescence device of the present invention include organometallic complexes, where the metal atom is usually a transition metal, preferably in the fifth or sixth period, Group 6 to 11 elements, more preferably group 8 to 10 elements are targeted. Specific examples include iridium and platinum. Examples of the ligand include 2-phenylpyridine and 2- (2'-benzothienyl) pyridine, and the carbon atom on these ligands is directly bonded to the metal. Another example is a porphyrin or tetraazaporphyrin ring complex, and the central metal includes platinum. For example, the following known compounds are suitably used as the phosphorescent material (where Ph represents a phenyl group).

Furthermore, the material used for the anode of the organic electroluminescence device of the present invention is preferably a material having a work function (4 eV or more) metal, alloy, electrically conductive compound or a mixture thereof as an electrode material. Specific examples of such an electrode substance include metals such as Au and conductive materials such as CuI, ITO, SnO ₂ and ZnO. In order to form this anode, a thin film can be formed from these electrode materials by a method such as vapor deposition or sputtering. The anode desirably has such a characteristic that when light emitted from the light emitting layer is extracted from the anode, the transmittance of the anode for light emission is greater than 10%. The sheet resistance of the anode is preferably several hundred Ω / □ or less. Further, although the film thickness of the anode depends on the material, it is usually selected in the range of 10 nm to 1 μm, preferably 10 to 200 nm.

  The material used for the cathode of the organic electroluminescence device of the present invention is a material having a work function (4 eV or less) metal, alloy, electrically conductive compound and a mixture thereof as an electrode material. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / silver alloy, aluminum / aluminum oxide, aluminum / lithium alloy, indium, and rare earth metals. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. Here, when light emitted from the light-emitting layer is extracted from the cathode, the transmittance of the cathode for light emission is preferably greater than 10%. The sheet resistance as a cathode is preferably several hundred Ω / □ or less, and the film thickness is usually 10 nm to 1 μm, preferably 50 to 200 nm.

  Regarding the method for producing the organic electroluminescence device of the present invention, an anode, a light emitting layer, a hole injection layer as necessary, and an electron injection layer as necessary are formed by the above materials and methods, and finally a cathode is formed. What is necessary is just to form. Moreover, an organic electroluminescent element can also be produced from the cathode to the anode in the reverse order.

  This organic electroluminescence element is manufactured on a translucent substrate. This light-transmitting substrate is a substrate that supports the organic electroluminescence element. Regarding the light-transmitting property, it is desirable that the light transmittance in the visible region of 400 to 700 nm is 50% or more, preferably 90% or more. Further, it is preferable to use a smoother substrate.

  These substrates have mechanical and thermal strengths and are not particularly limited as long as they are transparent. For example, glass plates, synthetic resin plates and the like are preferably used. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the synthetic resin plate include plates such as polycarbonate resin, acrylic resin, polyethylene terephthalate resin, polyether sulfide resin, and polysulfone resin.

  As a method for forming each layer of the organic electroluminescence device of the present invention, a dry film forming method such as vacuum deposition, electron beam irradiation, sputtering, plasma, ion plating, or a wet film forming method such as spin coating, dipping, or flow coating is used. Any method of law can be applied. In addition, Special Table 2002-53482, S.I. T.A. Lee, et al. , Proceedings of SID'02, p. LITI (Laser Induced Thermal Imaging) method described in 784 (2002), printing (offset printing, flexographic printing, gravure printing, screen printing), inkjet, and the like can also be applied.

  The organic layer is particularly preferably a molecular deposited film. Here, the molecular deposited film is a thin film formed by deposition from a material compound in a gas phase state or a film formed by solidifying from a material compound in a solution state or a liquid phase state. Can be classified from a thin film (accumulated film) formed by the LB method according to a difference in an agglomerated structure and a higher-order structure and a functional difference resulting therefrom. Further, as disclosed in JP-A-57-51781, a binder such as a resin and a material compound are dissolved in a solvent to form a solution, which is then thinned by a spin coat method or the like. An organic layer can be formed. The film thickness of each layer is not particularly limited, but if the film thickness is too thick, a large applied voltage is required to obtain a constant light output, resulting in poor efficiency. Conversely, if the film thickness is too thin, pinholes, etc. And it becomes difficult to obtain sufficient light emission luminance even when an electric field is applied. Accordingly, the thickness of each layer is suitably in the range of 1 nm to 1 μm, but more preferably in the range of 10 nm to 0.2 μm.

  Further, in order to improve the stability of the organic electroluminescence element against temperature, humidity, atmosphere, etc., a protective layer may be provided on the surface of the element, or the entire element may be covered or sealed with a resin or the like. In particular, when the entire element is covered or sealed, a photocurable resin that is cured by light is preferably used.

  The current applied to the organic electroluminescence element of the present invention is usually a direct current, but a pulse current or an alternating current may be used. The current value and the voltage value are not particularly limited as long as the element is within a range not destroying the element. However, considering the power consumption and life of the element, it is desirable to efficiently emit light with as little electrical energy as possible.

  The organic electroluminescence element driving method of the present invention can be driven not only by the passive matrix method but also by the active matrix method. The method for extracting light from the organic electroluminescence device of the present invention is applicable not only to the method of bottom emission for extracting light from the anode side but also to the method of top emission for extracting light from the cathode side. These methods and techniques are described in Keiji Kido, “All about organic electroluminescence”, published by Nihon Jitsugyo Shuppansha (published in 2003).

  Examples of the main method of full colorization of the organic electroluminescence element of the present invention include a three-color coating method, a color conversion method, and a color filter method. In the three-color coating method, an evaporation method using a shadow mask, an ink jet method, and a printing method can be used. In addition, Special Table 2002-53482, S.I. T.A. Lee, et al. , Proceedings of SID'02, p. 784 (2002) can also be used. The laser thermal transfer method (also referred to as Laser Induced Thermal Imaging, LITI method) can also be used. In the color conversion method, a blue light emitting layer is used to convert green and red having a longer wavelength than blue through a color conversion (CCM) layer in which fluorescent dyes are dispersed. The color filter method uses a white light emitting organic electroluminescence element to extract light of the three primary colors through the color filter for liquid crystal. In addition to these three primary colors, some white light is extracted as it is and used for light emission. As a result, the luminous efficiency of the entire device can be increased.

  Furthermore, the organic electroluminescence element of the present invention may adopt a microcavity structure. This is an organic electroluminescence element having a structure in which a light emitting layer is sandwiched between an anode and a cathode, and the emitted light causes multiple interference between the anode and the cathode, but the reflectance of the anode and the cathode, A technology that actively utilizes the multiple interference effect and controls the emission wavelength extracted from the device by appropriately selecting the optical characteristics such as transmittance and the film thickness of the organic layer sandwiched between them. is there. Thereby, it is also possible to improve the emission chromaticity. For the mechanism of this multiple interference effect, see J.A. Yamada et al., AM-LCD Digest of Technical Papers, OD-2, p. 77-80 (2002).

  As described above, the present organic electroluminescence element can obtain long-time light emission with a low driving voltage. Therefore, this organic electroluminescence device is used as a flat panel display such as a wall-mounted television and various flat light emitters, as well as a light source such as a copying machine and a printer, a light source such as a liquid crystal display and instruments, a display board, a marker lamp, etc. Application to is considered.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples at all.

  First, synthesis of a compound used as the material for an organic electroluminescence element of the present invention will be described.

Example 1
Synthesis Method of Compound (1) In a tetrahydrofuran (100 ml) solution containing 5.01 g (0.021 mol) of 5-bromo-2- (phenyl) -5,5′-bithiazole at −78 ° C. in a nitrogen atmosphere, 15.0 ml of n-butyllithium (1.66 M hexane solution) was added dropwise and stirred for 1 hour, and then 1.84 g (0.0088 mol) of tris (2,4-pentanedionato) iron (III) in tetrahydrofuran (25 ml). ) Was added dropwise. Then, after heating up to room temperature, it stirred for further 4 hours and concentrated the reaction liquid with the rotary evaporator. Thereafter, the residue was purified by column chromatography to obtain 1.2 g of 2,2-bis (4-phenyl) -5,5′-bithiazole as the compound (1).

Examples 2-110
The compounds in Table 1 were synthesized by combining the following reaction formulas 1 to 3.

  The compound group represented by the general formula [1] can be obtained by a known method. (For example, Journal of the American Chemical Society, 127, 5336, published in 2005)

Reaction formula 1

In Reaction Scheme 1, R ¹ represents a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic complex. Represents a cyclic group. In addition, as a synthesis method, tetrakis (triphenylphosphine) palladium was added in an amount of 0.1 equivalent of 2-bromothiazole derivative (II) to 1 equivalent of boronic acid derivative (II) under a nitrogen stream. A thiazole derivative (III) can be obtained by adding 05 equivalents and 3 equivalents of a 2M aqueous potassium carbonate solution and stirring with heating.

Reaction formula 2

  As a synthesis method, a solution in which 1.2 equivalents of bromine and 100 ml of carbon tetrachloride are mixed with 1 equivalent of thiazole derivative (III) is heated. Thereafter, the mixture is cooled to room temperature, extracted with dichloromethane, the organic layer is washed with water, dried over magnesium sulfate, and concentrated. Thereafter, after washing with hexane and vacuum drying, 5-bromothiazole derivative (IV) can be obtained.

Reaction formula 3

In Reaction Formula 3, R ² has the same meaning as that of R ¹ described above. As a synthesis method, 2.2 equivalents of n-butyllithium was dropped into a tetrahydrofuran solution containing 5-bromothiazole derivatives (IV) and (V) and stirred at −78 ° C. in a nitrogen atmosphere, Tetrahydrofuran of (2,4-pentanedionato) iron (III) is added dropwise. Then, after returning to room temperature, it stirs further and concentrates a reaction liquid with a rotary evaporator. Thereafter, the residue can be purified by column chromatography to obtain the 5,5′-bithiazole derivative (VI).

About the structure of the compound which is the organic electroluminescent element material of the present invention obtained by combining the above reaction formulas 1 to 3, the mass spectrum, ¹ H-NMR, ¹³ C-NMR is the same as in Example 1. Identified by Table 7 shows the synthesized compounds, the reaction formulas used, and the measurement results of the mass spectra of the compounds. The compound numbers are the same as those described in Table 1 in this specification.

Table 7

Examples of Organic Electroluminescent Element Hereinafter, the organic electroluminescent element using the organic electroluminescent element material of the present invention will be described with reference to the following examples, but the present invention is not limited to the following examples. In the examples, all mixing ratios are weight ratios unless otherwise specified. Vapor deposition (vacuum deposition) was performed in a vacuum of 10 ⁻⁶ Torr under conditions where temperature control such as heating and cooling of the substrate was not performed. The light emission characteristics of the element were measured using an organic electroluminescence element having a light emitting element area of 2 mm × 2 mm.

Example 111
On the washed glass plate with an ITO electrode, HTM7 of Table 3 was vacuum-deposited to obtain a hole injection layer having a thickness of 60 nm. Subsequently, the compound (1) in Table 1 of this invention was vacuum-deposited, and the light emitting layer with a film thickness of 20 nm was obtained. Furthermore, tris (8-hydroxyquinolino) aluminum complex (Alq3) was vacuum-deposited to form an electron injection layer having a thickness of 20 nm, on which first lithium fluoride was deposited to 1 nm and then aluminum (Al) was deposited to 150 nm. Thus, an electrode was formed to obtain an organic electroluminescence element. The chromaticity when this element was driven to 6 V was blue light emission of CIE (x, y) = (0.16, 0.13). The luminance half life when this device was driven at a constant current at room temperature with an emission luminance of 500 (cd / m ² ) was measured. Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 8.

Examples 112-220
A device was prepared in the same manner as in Example 111 except that the compounds in Table 8 were used instead of the compound (1). The luminance half life when this device was driven at a constant current at room temperature with an emission luminance of 500 (cd / m ² ) was measured. Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 8.

Comparative Example 1
A device was prepared in the same manner as in Example 111 except that a light emitting layer was prepared using the compound (A) shown below. The chromaticity when this element was driven to 6 V was blue light emission of CIE (x, y) = (0.19, 0.18). The device was measured for luminance and half-life when the device was driven at a constant current at room temperature with an emission luminance of 500 (cd / m ² ). Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 8.

Table 8

  As is apparent from Table 8, all the compounds of the present invention had a longer lifetime and higher luminance than the device prepared in Comparative Example 1.

Example 221
On the glass plate with an ITO electrode, HIM4 of Table 2 was vacuum-deposited to obtain a hole injection layer having a thickness of 70 nm. Next, the compound (1) and the compound (B) in Table 1 were co-evaporated at a composition ratio of 5: 100 to form a light-emitting layer having a thickness of 40 nm. Further, Alq3 was deposited to form an electron injection layer having a thickness of 20 nm. A cathode was formed thereon by vapor deposition of 1 nm of lithium oxide (Li ₂ O) and 100 nm of Al to obtain an organic electroluminescence device. When this device was driven at a direct current of 10 V, the external quantum efficiency was 3.6%. In addition, the luminance half life was measured when the device was driven at a constant current with an emission luminance of 350 (cd / m ² ). Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 9.

Examples 222-269
A device was prepared in the same manner as in Example 221 except that the compounds in Table 9 were used instead of the compound (1). All of these elements exhibited an external quantum efficiency of 3% or more at a DC voltage of 10V. In addition, the luminance half life was measured when the device was driven at a constant current with an emission luminance of 350 (cd / m ² ). Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 9.

Comparative Example 2
A device was prepared in the same manner as in Example 221 except that the compound (A) was used instead of the compound (1). The luminance half-life when this device was driven at a constant current at room temperature at an emission luminance of 350 (cd / m ² ) was measured. Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 9.

Table 9

  As is clear from Table 9, all the materials for organic electroluminescence elements of the present invention had a longer life and higher luminance than the element prepared in Comparative Example 2.

Example 270
On the glass plate with an ITO electrode, HIM9 of Table 2 was vacuum-deposited to obtain a hole injection layer having a thickness of 80 nm. Next, the compound (B) and the compound (1) were co-evaporated at a weight composition ratio of 100: 3 to form a light emitting layer having a thickness of 30 nm. Further, a compound (C) was deposited to form an electron injection layer having a thickness of 30 nm. On top of that, a cathode was formed by vapor deposition of 1 nm of Li ₂ O and 100 nm of Al to obtain an organic electroluminescence device. This device showed an external quantum efficiency of 3.5% at a DC voltage of 10V. In addition, the luminance half life was measured when the device was driven at a constant current with an emission luminance of 350 (cd / m ² ). Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 10.

Examples 271 to 290
A device was prepared in the same manner as in Example 270 except that the compounds in Table 10 were used instead of the compound (1). All of these devices had an external quantum efficiency of 3% or more at a DC voltage of 10 V, and the luminance half-life was measured when the device was driven at a constant current with an emission luminance of 350 (cd / m ² ). Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 10.

Comparative Example 3
A device was prepared in the same manner as in Example 270 except that the compound (A) was used instead of the compound (1). The luminance half-life when this device was driven at a constant current at room temperature at an emission luminance of 350 (cd / m ² ) was measured. Further, the initial luminance when driven at a current density of 12.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C. were measured. The results are shown in Table 10.

Table 10

  As is clear from Table 10, all the materials for organic electroluminescent elements of the present invention had a longer lifetime and higher luminance than the element prepared in Comparative Example 3.

Example 291
On the washed glass plate with an ITO electrode, HTM6 of Table 3 was vacuum-deposited to obtain a hole injection layer having a thickness of 60 nm. Subsequently, the compound (1) in Table 1 of this invention was vacuum-deposited, and the 60-nm-thick electron transport light emitting layer was obtained. An electrode was formed thereon by first depositing 1 nm of lithium fluoride and then 200 nm of Al, to obtain an organic electroluminescence device. This element exhibited blue light emission with an emission luminance of 6300 (cd / m ² ) at 8V.

Example 292
On the glass plate with an ITO electrode, HIM9 was vapor-deposited to form a 65 nm-thick hole injection layer. Next, the compound (2) and the compound (D) in Table 1 were co-evaporated at a composition ratio of 100: 3 to form a light emitting layer having a thickness of 45 nm. Further, ES2 in Table 6 was deposited to form an electron transport layer having a thickness of 20 nm. Further, Alq3 is vacuum-deposited to form an electron injection layer having a film thickness of 10 nm. On top of that, lithium fluoride is first deposited to 1 nm, and then Al is deposited to 200 nm to form an electrode. Organic electroluminescence An element was obtained. When this device was driven at a constant current at room temperature with an emission luminance of 500 (cd / m ² ), the luminance half life was 1000 hours or more.

Example 293
PEDOT / PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, BAYTRON P VP CH8000 manufactured by Bayer) manufactured on a cleaned glass plate with an ITO electrode by a spin coating method A hole injection layer having a thickness of 40 nm was obtained. Next, 60% of PVK (polyvinylcarbazole), 3% of compound (1), and 37% of electron transport material (compound (E)) were dissolved in toluene at a concentration of 2.0 wt%, and 70 nm by spin coating method. A light emitting layer having a film thickness was obtained. Furthermore, after depositing Ca to 20 nm thereon, Al was deposited to 200 nm to form an electrode to obtain an organic electroluminescence device. When this device was subjected to a current test, blue light emission with a maximum light emission luminance of 380 cd / m ² was obtained.

Example 294
PEDOT / PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, BAYTRON P VP CH8000 manufactured by Bayer) manufactured on a cleaned glass plate with an ITO electrode by a spin coating method A hole injection layer having a thickness of 40 nm was obtained. Next, 60% of PVK (polyvinylcarbazole), 3% of compound (3), and 37% of electron transport material (compound (F)) were dissolved in toluene at a concentration of 2.0 wt%, and 70 nm by spin coating method. A light emitting layer having a film thickness was obtained. Further thereon, 20 nm of Ca was vapor-deposited, and then 200 nm of Al was vapor-deposited to form an electrode to obtain an organic electroluminescence element (102). When this device was subjected to an energization test, blue light emission with a maximum light emission luminance of 360 cd / m ² was obtained.

Example 295
On the washed glass plate with an ITO electrode, HTM8 of Table 3 was vacuum-deposited to obtain a hole injection layer having a thickness of 70 nm. Subsequently, the compound (B) was vacuum-deposited to obtain a light emitting layer having a thickness of 20 nm. Further, the compound (17) in Table 1 of the present invention was vacuum-deposited to obtain an electron transport layer having a thickness of 60 nm. On top of this, 1 nm of lithium fluoride and then 200 nm of Al were vapor-deposited to form an electrode to obtain an organic electroluminescence device. This element showed blue light emission with an emission luminance of 610 (cd / m ² ) at 8V.

Example 296
On the washed glass plate with an ITO electrode, the compound (49) in Table 1 of the present invention was vacuum-deposited to obtain a hole injection layer having a thickness of 20 nm. Subsequently, the compound (B) was vacuum-deposited to obtain a light emitting layer having a thickness of 25 nm. On top of that, Alq3 is vacuum-deposited to form an electron injection layer having a thickness of 20 nm, and then an electrode is formed by first depositing 1 nm of lithium fluoride and then 150 nm of Al to form an organic electroluminescence device. It was. This element showed blue light emission with an emission luminance of 590 (cd / m ² ) at 8V.

  As described above, a high-performance electroluminescent element can be created by using the organic electroluminescent element material shown in the present invention. It is clear that remarkably high performance is exhibited with respect to the comparative compound, and high luminance, long life and high color purity blue light emission of the organic electroluminescence device can be achieved.

Claims (7)

A material for an organic electroluminescence device, which is a compound represented by the following general formula [1].
General formula [1]

Wherein R ¹ and R ² are each independently a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted Represents a monovalent aromatic heterocyclic group.) R ¹ and R ² are each independently a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted monovalent aromatic complex having 3 to 18 carbon atoms. The organic electroluminescent device material according to claim 1, wherein the material is a cyclic group. R ¹ and R ² are each independently a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted monovalent aromatic complex having 6 to 18 carbon atoms. 3. The material for an organic electroluminescence element according to claim 1, which is a cyclic group. 4. R ¹ and R ² are each independently an unsubstituted monovalent aromatic hydrocarbon group or an unsubstituted monovalent aromatic heterocyclic group. The material for organic electroluminescent elements as described.   In the organic electroluminescent element formed by forming a plurality of organic layers including a light emitting layer between a pair of electrodes, at least one of the organic layers includes the material for an organic electroluminescent element according to any one of claims 1 to 4. An organic electroluminescence device comprising:   In the organic electroluminescent element formed by forming a light emitting layer or a plurality of organic layers including a light emitting layer between a pair of electrodes, the light emitting layer contains the material for an organic electroluminescent element according to any one of claims 1 to 4. An organic electroluminescence device. A compound represented by the following general formula [1].
General formula [1]

Wherein R ¹ and R ² are each independently a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted Represents a monovalent aromatic heterocyclic group.)