JP2009029725A - Compound having carbazolyl group and use thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compound having carbazolyl groups and usable as a material for organic EL elements. <P>SOLUTION: An organic EL material is produced by synthesizing a compound having carbazolyl groups and obtained by using one molecule of a fluorene derivative as a center and bonding each one molecule of a carbazole derivative to the symmetrical positions of the center molecule. The organic EL element produced from a compound having carbazolyl groups among a carbazole derivative-fluorene derivative-carbazole derivative exhibits low-voltage driving performance, long life, etc., and accordingly is usable as a flat light, a liquid crystal display, a displaying plate, a marker light, etc. The molecular weight of the compound having carbazolyl groups is especially preferably ≤1,100 and too high molecular weight of the compound may cause difficulty in the evaporation in the case of producing an element by evaporation coating. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a novel compound having a carbazolyl group, and more specifically, when used in an organic electroluminescence device (hereinafter abbreviated as an organic EL device), it can be formed by vapor deposition and has excellent performance (low voltage driving). , A compound having a carbazolyl group that exhibits a long lifetime.

  In recent years, organic EL elements have been required to have a long lifetime. There are various factors that may affect the lifetime of the element (see Non-Patent Document 1). As one of the factors, the glass transition temperature (Tg) of the material constituting the element has a large effect on the lifetime of the element. It is considered a thing. That is, it has been pointed out that when the temperature of the element exceeds the Tg of the constituent material due to the use environment of the element or the heat generated during driving, the material crystallizes and a non-light emitting region called a dark spot is generated. . For this reason, development of materials exhibiting higher Tg has been actively studied.

  Application of carbazole derivatives to various functional materials and electronic materials has been studied. Utilizing the fact that the carbazole skeleton has a hole transporting property and a structure having high heat resistance, application to, for example, a charge transport material of an electrophotographic photosensitive member or a material for an organic EL element has been studied. ing. As typical examples, polyvinyl carbazole (PVK) and N, N′-dicarbazoyl-4,4′-biphenyl (CBP) are widely studied as materials for organic EL devices (Non-patent Documents 2 and 3). reference). Although carbazoles such as PVK and CBP have a relatively high Tg and heat resistance, they have a highly symmetrical structure. Therefore, when a thin film is formed by vacuum deposition or spin coating, the stability of the film is improved. However, it has a problem that it is easily crystallized and the lifetime of the device is extremely short.

  Fluorene derivatives have also been studied as organic EL materials exhibiting high heat resistance and blue light emission. Typical examples include polyfluorene (PF) and derivatives thereof (see Non-Patent Document 4 and Patent Documents 1 to 6).

  In addition, as derivatives having a low-molecular carbazolyl group, thiophene derivatives linked by a divalent linking group (see Patent Document 7) and carbazole derivatives having a 2-fluorenyl group in a partial structure have been reported (patents). Reference 8). In addition, carbazole derivatives to which fluorene is bonded (see Patent Document 9) and derivatives in which a carbazole skeleton is substituted with a triphenylsilyl group have been studied (see Patent Document 10). However, the organic EL element produced using these derivatives has a problem that the light emission lifetime is short.

Shizutoki Tokito, Chiba Adachi, Hideyuki Murata, Organic EL Display, Ohmsha, 2004, 139 pages Applied Physics Letters, 2001, 78, 278 Journal of the American Chemical Society 2001, 123, 4304 Macromolecules 2005, 38, 4970-4976 WO2006 / 126439 WO2006 / 096399 WO 2006/096332 WO2004 / 072205 JP-T-2006-520409 WO2004 / 029134 JP 2004-217557 A JP 2005-289914 A WO03 / 090502 A2 publication US2006 / 0177691 A1 publication

  The subject of this invention is providing the compound which has a carbazolyl group which exhibits characteristics, such as a low voltage drive and long life, when an organic EL element is produced by vapor deposition.

As a result of intensive studies to solve the above problems, the present inventors have arrived at the present invention.
That is, the present invention relates to a compound having a carbazolyl group represented by the following general formula [1].

General formula [1]

(In the formula, A ¹ and A ² each independently represent a carbazolyl group represented by the following general formula [2], and R ^{1 to} R ² each independently represent a hydrogen atom or a monovalent organic group. And R ^{3 to} R ⁸ each independently represents a hydrogen atom, a halogen atom, or a monovalent organic residue.)

General formula [2]

(In the formula, Ar ¹ represents a monovalent aliphatic hydrocarbon group, a monovalent aromatic hydrocarbon group, or a monovalent aromatic heterocyclic group, and R ^{9 to} R ¹⁵ are each independently hydrogen. Represents an atom, a halogen atom, or a monovalent organic residue.)

The present invention also relates to a compound in which Ar ¹ has the above carbazolyl group, which is a monovalent aromatic hydrocarbon group.

The present invention also relates to a compound having the carbazolyl group, wherein Ar ¹ is a phenyl group which may have a substituent represented by the following general formula [3].

General formula [3]

(Wherein R ^{16 to} R ²⁰ represent a hydrogen atom, a halogen atom, or a monovalent organic residue, and adjacent substituents may be bonded to form a new ring.)
Moreover, this invention relates to the compound which has the said carbazolyl group whose R < ³ > -R < ⁸ > is a hydrogen atom.

Moreover, this invention relates to the compound which has the said carbazolyl group whose R < ⁹ > -R < ¹⁵ > is a hydrogen atom.

  The present invention also relates to a material for an organic electroluminescence device comprising the above compound having a carbazolyl group.

  Further, the present invention provides an organic electroluminescent device comprising a light emitting layer or a plurality of organic layers including a light emitting layer between a pair of electrodes, wherein at least one layer of the light emitting layer comprises the material for an organic electroluminescent device. It is related with the organic electroluminescent element which comprises.

  Moreover, 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 comprises the material for an organic electroluminescent device. The present invention relates to an organic electroluminescence element.

  In addition, the present invention provides an organic electroluminescence 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 comprises a phosphorescent material and the organic electroluminescent device. The present invention relates to an organic electroluminescence device comprising a material.

  An organic EL device using the compound having a carbazolyl group of the present invention as a material for an organic EL device is driven at a low voltage and has a long life, and thus is suitable as a flat panel display such as a wall-mounted television or a flat light emitter. It can be used, and 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, the compound having a carbazolyl group represented by the general formula [1] will be described.

First, R ¹ and R ² , R ^{3 to} R ⁸ , R ^{9 to} R ¹⁵ will be described. R ¹ and R ² each independently represents a hydrogen atom or a monovalent organic residue, and R ^{3 to} R ⁸ and R ^{9 to} R ¹⁵ each independently represent a hydrogen atom, a halogen atom or a monovalent group. Represents an organic residue.

  Here, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  The monovalent organic residue includes a monovalent aliphatic hydrocarbon group which may have a substituent, a monovalent aromatic hydrocarbon group which may have a substituent, and a substituent. Monovalent aliphatic heterocyclic group, monovalent aromatic heterocyclic group optionally having substituent, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group An acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, and the like.

  Here, the monovalent aliphatic hydrocarbon group refers to a monovalent aliphatic hydrocarbon group having 1 to 18 carbon atoms, such as an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group. Can be given.

  Therefore, as the alkyl group, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, hexyl group, heptyl group, octyl group, C1-C18 alkyl groups, such as a decyl group, a dodecyl group, a pentadecyl group, and an octadecyl group, are mentioned.

  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 -An alkenyl group having 2 to 18 carbon atoms such as an octadecenyl group.

  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. Examples thereof include alkynyl groups having 2 to 18 carbon atoms.

  Examples of the cycloalkyl group include cycloalkyl groups having 3 to 18 carbon atoms such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclooctadecyl group.

  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 a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a 2,4-xylyl group, a p-cumenyl group, and a mesityl group. Examples thereof include monovalent monocyclic aromatic hydrocarbon groups having 6 to 18 carbon atoms.

  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 thereof include monovalent condensed ring hydrocarbon groups having 10 to 18 carbon atoms such as acenaphthyl group, 2-azurenyl group, 1-pyrenyl group and 2-triphenylyl group.

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

  Examples of the monovalent aliphatic heterocyclic group include monovalent aliphatic heterocyclic groups having 3 to 18 carbon atoms such as a 2-pyrazolino group, a piperidino group, a morpholino group, and a 2-morpholinyl group.

  Examples of the monovalent aromatic heterocyclic group include triazolyl group, 3-oxadiazolyl group, 2-furyl group, 3-furyl group, 2-thienyl group, 3-thienyl group, 1-pyrrolyl group, 2- Pyrrolyl, 3-pyrrolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrazyl, 2-oxazolyl, 3-isoxazolyl, 2-thiazolyl, 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, 8-quinolyl group, 1-isoquinolyl group A monovalent aromatic compound having 2 to 18 carbon atoms such as a group, 2-quinoxalinyl group, 2-benzofuryl group, 2-benzothienyl group, N-indolyl group, N-carbazolyl group, N-acridinyl group. Ring group, and the like.

  Examples of the alkoxyl group include C1-C8 alkoxyl groups such as methoxy group, ethoxy group, propoxy group, butoxy group, tert-butoxy group, octyloxy group, and tert-octyloxy group.

  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 give.

  Examples of the alkylthio group include C1-C8 alkylthio groups such as a methylthio group, an ethylthio group, a tert-butylthio group, a hexylthio group, and an octylthio group.

  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 Examples thereof include substituted amino groups having 2 to 26 carbon atoms such as naphthyl-N-phenylamino group.

  Examples of the acyl group include acyl groups having 2 to 14 carbon atoms such as an acetyl group, a propionyl group, a pivaloyl group, a cyclohexylcarbonyl group, a benzoyl group, a toluoyl group, an anisoyl group, and a cinnamoyl group.

  Moreover, as an alkoxycarbonyl group, C2-C14 alkoxycarbonyl groups, such as a methoxycarbonyl group, an ethoxycarbonyl group, a benzyloxycarbonyl group, are mention | raise | lifted.

  Moreover, as an aryloxycarbonyl group, C2-C14 aryloxycarbonyl groups, such as a phenoxycarbonyl group and a naphthyloxycarbonyl group, are mention | raise | lifted.

  Moreover, as an alkylsulfonyl group, C2-C14 alkylsulfonyl groups, such as a mesyl group, an ethylsulfonyl group, a propylsulfonyl group, are mention | raise | lifted.

  Moreover, as an arylsulfonyl group, C2-C14 arylsulfonyl groups, such as a benzenesulfonyl group and p-toluenesulfonyl group, are mention | raise | lifted.

The monovalent aliphatic hydrocarbon group, aromatic hydrocarbon group, aliphatic heterocyclic group and aromatic heterocyclic group in R ¹ and R ² , R ^{3 to} R ⁸ and R ^{9 to} R ¹⁵ It may be substituted with a substituent. Such substituents include halogen atoms, cyano groups, alkoxyl groups, aryloxy groups, alkylthio groups, arylthio groups, substituted amino groups, acyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, alkylsulfonyls. Group, arylsulfonyl group and the like. Examples of these substituent groups include those described above.

Further, Ar ¹ in the general formula [2] represents a monovalent aliphatic hydrocarbon group, a monovalent aromatic hydrocarbon group, or a monovalent aromatic heterocyclic group. The monovalent aliphatic hydrocarbon group, monovalent aromatic hydrocarbon group, or monovalent aromatic heterocyclic group referred to here is R ¹ and R ² , R ^{3 to} R ⁸ , R ^{9 to} R ^15. In the monovalent organic residue.

A preferable example of Ar ¹ is a monovalent aromatic hydrocarbon group, and a more preferable example is General Formula [3].

In the general formula [3], R ^{16 to} R ^{20 each} represents a hydrogen atom or a monovalent organic residue, and these substituents may be bonded to each other to form a new ring.

Furthermore, examples of the monovalent organic residue mentioned here include those described in the section of monovalent organic residues in R ¹ and R ² , R ^{3 to} R ⁸ , and R ^{9 to} R ¹⁵ . Examples of the substituent that may be included include the halogen atoms described above and monovalent organic residues.

  Examples of the group in which these substituents may be bonded to each other to form a new ring include a 1-naphthyl group, a 2-naphthyl group, a quinolyl group, and the like.

Further, among R ¹⁶ to R ^20, examples of particularly preferred substituents, R ¹⁸ is, like hydrogen atom, a phenyl group, a biphenyl group, a tolyl group, and xylyl group, a methyl group, an ethyl group, and a fluorine atom The others are hydrogen atoms.

Preferred examples of R ¹ and R ² in the general formula [1] include a monovalent aliphatic hydrocarbon group, a monovalent aromatic hydrocarbon group, and a monovalent aromatic heterocyclic group, and more preferable. Examples thereof include a monovalent aliphatic hydrocarbon group and a monovalent aromatic hydrocarbon group, and particularly preferable examples include a monovalent aromatic hydrocarbon group.

Among R ^{3 to} R ⁸ in the general formula [1], a particularly preferable one is a hydrogen atom. Moreover, as a preferable thing as R < ⁹ > -R < ¹⁹ > in General formula [2], a hydrogen atom is mention | raise | lifted.

  As mentioned above, although the compound which has carbazolyl group represented by General formula [1] used for this invention was demonstrated, when using the compound which has these carbazolyl groups as an organic EL element material, as a molecular weight of a compound, 1500 or less Is preferably 1,300 or less, more preferably 1200 or less, and particularly preferably 1100 or less. This is because, when the molecular weight is large, there is a concern that vapor deposition is difficult when an element is formed by vapor deposition.

Representative examples of the compounds of the present invention are shown in Table 1 below, but the present invention is not limited to these representative examples. In Table 1, n-C ₆ H ₁₃ represents an n-hexyl group, and n-C ₈ H ₁₇ represents an n-octyl group.

Table 1

  The compound having a carbazolyl group of the present invention can be used for various applications. For example, functions such as sensitization effect, heat generation effect, color development effect, color fading effect, phosphorescence effect, phase change effect, photoelectric conversion effect, photomagnetic effect, photocatalytic effect, photocatalytic effect, light modulation effect, optical recording effect, radical generation effect, etc. It can also be used as a material, or conversely, a material having a light emitting function due to these effects. More specifically, light emitting materials, photoelectric conversion materials, optical recording materials, image forming materials, photochromic materials, organic EL materials, photoconductive materials, dichroic materials, radical generating materials, acid generating materials, base generating materials, phosphorescent materials Materials, nonlinear optical materials, second harmonic generation materials, third harmonic generation materials, photosensitive materials, light absorption materials, near infrared absorption materials, photochemical hole burning materials, optical sensing materials, optical marking materials, photochemical treatment Examples thereof include sensitizing materials, optical phase change recording materials, photosintered recording materials, magneto-optical recording materials, and dyes for photodynamic therapy.

  Of these various uses, the organic EL material (organic EL material, organic EL element material) is particularly preferably used.

  In the case of use as a material for an organic EL element, a high-purity material is particularly required. In such a case, the compound having a carbazolyl group of the present invention can be obtained by a sublimation purification method, a recrystallization method, a recrystallization method, or the like. A precipitation method, a zone melting method, a column purification method, an adsorption method, etc., 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 beforehand. 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 EL element that can be prepared using the compound having a carbazolyl group of the present invention will be described in detail.

  The organic EL 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, the single layer type organic EL element is an element composed of only a light emitting layer between an anode and a cathode. Point to. On the other hand, the multilayer organic EL element facilitates 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 the purpose of this, it refers to a layer in which a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, and the like are laminated. Therefore, typical element configurations of the multilayer organic EL element 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 / positive 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 structure in which a multilayer structure of anode / light emitting layer / hole blocking layer / electron injection layer / cathode, (8) anode / light emitting layer / electron injection layer / cathode, etc., 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, an element configuration called “multi-photon emission” in which a part of the above-described multilayer organic EL element is multilayered has been proposed in recent years for the purpose of improving light extraction efficiency. For example, in an organic EL 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, the charge generating layer and the light emitting unit A method of laminating a plurality of layers is an example.

  The compound (organic EL device material) having a carbazolyl group of the present invention may be used in any of the above-described layers, but can be suitably used particularly for a light emitting layer, an electron injection layer, and an electron transport layer. The organic EL device material of the present invention can be used not only as a single compound but also as a combination of two or more compounds, that is, mixed, co-evaporated, laminated, etc. is there. Furthermore, in the light emitting layer, the electron injection layer, and the electron transport layer described above, they may be used together with other materials.

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 EL device 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 EL device material of the present invention are not particularly limited as long as they have the above-mentioned preferable properties. Any material can be selected and used from those commonly used as charge transport materials for holes in a conductive material and known materials used for hole injection layers of organic EL devices.

  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'-diphenyl Nzine, 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 can be mentioned, and these can be used for both hole injection materials and hole transport materials.

  Particularly, it is suitably used as a hole injection material. Table 2 below shows particularly preferred examples.

Table 2

  Moreover, as a hole transport material which can be used with the compound (organic EL element material) of this invention, the compound shown in following Table 3 is mention | raise | lifted.

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. Electrons can be transported by forming a thin film necessary for device fabrication and injecting electrons from the cathode. 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 And quinolinato) beryllium, bis (8-hydroxyquinolinato) zinc, and 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- Examples thereof include bis (1-naphthyl) -1,3,4-triazole, 1,4-bis [2- (5-phenyltriazolyl)] benzene and the like.

  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) ( 4-phenylphenolate) gallium complex compounds such as gallium, and nitrogen-containing condensed aromatic compounds such as 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP).

The light emitting layer of the organic EL device of the present invention preferably has the following functions.
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 compound of the present invention can be suitably used as a light emitting layer. Moreover, you may form a light emitting layer combining with another compound. For example, in order to obtain light emission in the visible region, particularly blue to green, fluorescent whitening agents such as benzothiazole, benzimidazole, and benzoxazole, metal chelated oxinoid compounds, and styrylbenzene 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 [ 4] to those having the structure of the general formula [6].

General formula [4]

(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 [5]

(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 [6]

(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-quinolinolate 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 EL 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.

  In the organic electroluminescence device of the present invention, a phosphorescent material can be used. 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 electroluminescent device of the present invention include organometallic complexes, where the metal atom is usually a transition metal, preferably in the fifth or sixth period, in terms of group, 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 is 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 EL 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 substance. 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 EL device of the present invention is a material having a small work function (4 eV or less) metal, alloy, electrically conductive compound and a mixture thereof as an electrode substance. 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 the 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 EL 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. do it. Moreover, an organic EL element can also be produced from the cathode to the anode in the reverse order.

  This organic EL element is manufactured on a translucent substrate. This translucent substrate is a substrate that supports the organic EL element, and for the translucency, it is desirable that the transmittance of light in the visible region of 400 to 700 nm is 50% or more, preferably 90% or more, Further, it is preferable to use a smooth 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 made of polycarbonate resin, acrylic resin, polyethylene terephthalate resin, polyether sulfide resin, polysulfone resin, and the like.

  As a method for forming each layer of the organic EL element 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. Either method can be applied. In addition, Special Tables 2002-534882 and S.A. 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 EL element with respect to temperature, humidity, atmosphere and the like, 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 EL 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 EL device driving method of the present invention can be driven not only by the passive matrix method but also by the active matrix method. Further, the method for extracting light from the organic EL 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 Shinji Kido, “All about organic EL”, published by Nihon Jitsugyo Shuppansha (published in 2003).

  The main methods of the full color method of the organic EL 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, there are a vapor deposition method using a shadow mask, an ink jet method and a printing method. In addition, Special Tables 2002-534882 and S.A. 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 EL element to extract light of three primary colors through a color filter for liquid crystal. In addition to these three primary colors, a part of white light is directly extracted and used for light emission. Thus, the luminous efficiency of the entire device can be increased.

  Furthermore, the organic EL element of the present invention may adopt a microcavity structure. This is because the organic EL element has a structure in which the light emitting layer is sandwiched between the anode and the cathode, and the emitted light causes multiple interference between the anode and the cathode, but the reflectance and transmission of the anode and the cathode. This is a technology that actively uses the multiple interference effect and controls the emission wavelength extracted from the device by appropriately selecting the optical characteristics such as the rate and the film thickness of the organic layer sandwiched between them. . 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 organic EL device using the compound having a carbazolyl group of the present invention can obtain long-term blue light emission at a low driving voltage. Therefore, this organic EL device can be 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 or a printer, a light source such as a liquid crystal display or an instrument, a display board, a marker lamp, etc. Can be applied.

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

Example 1
Synthesis Method of Compound (1) A synthesis scheme is shown in Reaction 1. (N-C ₆ H ₁₃ represents an n-hexyl group.)

Reaction 1

Hereinafter, the synthesis method will be described with reference to Reaction 1. Under a nitrogen atmosphere, 5.0 g (0.01 mol) of (I), 8.0 g (0.025 mol) of 3-bromo-9-phenylcarbazole (II), 0.96 g of tetrakis (triphenylphosphine) palladium, potassium carbonate (2M aqueous solution) 100 g and tetrahydrofuran 100 g were placed in a four-necked flask and heated to reflux for 5 hours. Thereafter, the reaction solution was poured into 400 ml of methanol, and the precipitated solid was collected by filtration and dried under hot vacuum to obtain 8.76 g of (III) (= compound (1)) as a crude product. The obtained crude product was purified by silica gel column chromatography, and further sublimation purification was performed. The compound was identified by mass spectrum (manufactured by Bruker Daltonics, Autoflex II), ¹ H-NMR, and ¹³ C-NMR (manufactured by JEOL, ECX-400P). ¹ H-NMR, ¹³ C-NMR, UV spectrum, and fluorescence (PL) spectrum of the compound (1) are shown in FIGS. The UV spectrum was measured with a Hitachi spectrophotometer (U-3500), and the fluorescence (PL) spectrum was measured with a Japan spectrofluorometer (FP-6500).

  In addition, (I) used for the synthesis | combination of a compound (1) used the commercially available reagent. As 3-bromo-9-phenylcarbazole (II), one synthesized according to the method described in WO2007 / 43484 was used.

Examples 2-40
In the synthesis method, the compounds shown in Table 1 were synthesized by combining the following reactions 2 to 7.

Reaction 2

R ^{16 to} R ²⁰ are substituents necessary for synthesizing the compound of the present invention, and each represents a hydrogen atom, a halogen atom, or a monovalent organic residue. As a synthesis method, Li-lithium produced by reacting a 3-bromo-9-phenylcarbazole derivative (IV) with n-butyllithium (n-BuLi) at -76 ° C. under a nitrogen stream in accordance with a conventional method, was produced. The derivative was reacted with B (OMe) ₃ to synthesize the desired boronic acid derivative (V) form.

Reaction 3

R ¹ and R ² are substituents necessary for synthesizing the compound of the present invention, and each independently represents a hydrogen atom or a monovalent organic residue. R ^{16 to} R ²⁰ are as defined above. As a synthesis method, the target compound is obtained by the same operation as in Example 1 except that the carbazole derivative (V) is reacted with 3 equivalents of the 2,7-dibromofluorene derivative (VI).

Reaction 4

Here, R < ⁹ > -R < ¹⁵ > is a substituent required in order to synthesize | combine the compound of this invention, and represents a hydrogen atom, a halogen atom, or a monovalent organic residue each independently. Ar ¹ represents a monovalent aliphatic hydrocarbon group, a monovalent aromatic hydrocarbon group, or a monovalent aromatic heterocyclic group. As a synthesis method, under a nitrogen stream at -78 ° C., 3-bromocarbazole derivative (VIII) was reacted with n-butyllithium to lithiate, and the resulting Li derivative was reacted with B (OMe) ₃ . The desired boronic acid derivative (IX) was synthesized.

Reaction 5

R ^{3 to} R ⁸ are substituents necessary for synthesizing the compound of the present invention, and each independently represents a hydrogen atom, a halogen atom, or a monovalent organic residue. Ar ¹ and R ^{9 to} R ¹⁵ are as defined above. The synthesis method is the same as in Example 1 except that 3 equivalents of the fluorene derivative (X) corresponding to (I) instead of (I) in Example 1 and the corresponding carbazole derivative (IX) instead of (II) are reacted. The target compound (XI) was obtained by the operation.

Reaction 6

R ^{3 to} R ⁸ are substituents necessary for synthesizing the compound of the present invention, and each independently represents a hydrogen atom, a halogen atom, or a monovalent organic residue. As a synthesis method, (X) was obtained by reacting fluorene derivative (XII) with an equal amount of bromine or N-bromosuccinimide in toluene according to a conventional method.

Reaction 7

R ^{3 to} R ⁸ and R ^{9 to} R ¹⁵ are substituents necessary for synthesizing the compound of the present invention and have the same meanings as described above. As the synthesis method, the target compound was easily obtained by the same operation as in Example 1.

  The structure of the compound of the present invention obtained by combining the above reactions 2 to 7 was identified by mass spectrum (manufactured by Bruker Daltonics, Autoflex II). The results are shown in Table 7. The compound numbers are the same as those in Table 1.

Table 7

Examples of Organic EL Device Hereinafter, preparation examples of organic EL devices using the compound of the present invention as a material for organic EL devices 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 and under conditions without temperature control such as substrate heating and cooling. In the evaluation of the light emission characteristics of the element, the characteristics of an organic EL element having an electrode area of 2 mm × 2 mm were measured.

Example 41
On the cleaned glass plate with an ITO electrode, HTM8 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 50 nm was obtained. Further, a tris (8-hydroxyquinolino) aluminum complex (Alq3) was vacuum-deposited to prepare a 20 nm-thick electron-injecting light-emitting layer. On top of this, first lithium fluoride was 1 nm and then aluminum (Al) was added. An electrode was formed by vapor deposition of 200 nm to obtain an organic EL device. 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 ). Table 8 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Examples 42-80
A device was produced in the same manner as in Example 41 except that the light emitting layer was produced using the compounds (2) to (40) shown in Table 1 instead of the compound (1). 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 ). Table 8 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Comparative Examples 1-4
A device was produced in the same manner as in Example 41 except that a light emitting layer was produced using the compounds (A), (B), (C), and (D) shown below. 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 ). Table 8 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Table 8

  As is clear from Table 8, all of the compounds of the present invention have a longer lifetime and higher luminance than the devices prepared using the compounds (A), (B), (C), and (D) of the comparative examples. Obtained.

Example 81
On the glass plate with an ITO electrode, HTM8 of Table 3 was vacuum-deposited to obtain a 60 nm-thick hole injection layer. Next, the compound (1) and the compound (E) in Table 1 were co-evaporated at a composition ratio of 100: 5 to form a light emitting layer having a thickness of 45 nm. Further, a compound (F) 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 EL device. This device showed an external quantum efficiency of 3.5% at a DC voltage of 10V. In addition, the luminance and half-life when driven at a constant current at an emission luminance of 300 (cd / m ² ) were measured. Table 9 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Examples 82-90
A device was prepared in the same manner as in Example 81 except that the compounds in Table 9 were used instead of the compound (1). These devices had an external quantum efficiency of 3% or more at a DC voltage of 10 V, and the luminance and half-life when driven at a constant current with an emission luminance of 200 (cd / m ² ) were measured. Table 9 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Comparative Examples 5 and 6
A device was prepared in the same manner as in Example 81 except that the compound (A) or the compound (B) and the compound (E) were co-evaporated at a weight composition ratio of 100: 5 to prepare a light emitting layer having a film thickness of 45 nm. . 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 ). Table 9 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Table 9

  As is clear from Table 9, all of the compounds of the present invention had a longer lifetime and higher luminance than the devices prepared using the compounds (A) and (B) of the comparative examples.

Example 96
On the glass plate with an ITO electrode, HTM8 of Table 3 was vacuum-deposited to obtain a 60 nm-thick hole injection layer. Next, the compound (G) and the compound (1) in Table 1 were co-evaporated at a weight composition ratio of 100: 3 to form a light emitting layer having a thickness of 45 nm. Further, a compound (H) 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 EL device. This device showed an external quantum efficiency of 3.5% at a DC voltage of 10V. In addition, the luminance and half-life when driven at a constant current at an emission luminance of 300 (cd / m ² ) were measured. Table 10 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Examples 97-105
A device was prepared in the same manner as in Example 96 except that the compounds in Table 10 were used instead of the compound (1). These devices had an external quantum efficiency of 3% or more at a DC voltage of 10 V, and the luminance and half-life when driven at a constant current at an emission luminance of 200 (cd / m ² ) were measured. Table 10 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Comparative Examples 7 and 8
A device was prepared in the same manner as in Example 96 except that the light emitting layer having a film thickness of 45 nm was formed by co-evaporating the compound (G) and the compound (A) or the compound (B) at a weight composition ratio of 100: 5. . 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 ). Table 10 shows the initial luminance when driven at a current density of 10 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 100 ° C.

Table 10

  As is clear from Table 10, all of the compounds of the present invention had a longer lifetime and higher luminance than the devices prepared using the compounds (A) and (B) of the comparative examples.

Example 106
On the cleaned glass plate with an ITO electrode, HTM8 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 carrying layer and light emitting layer were obtained. An electrode was formed thereon by first depositing 1 nm of lithium fluoride and then 200 nm of Al, to obtain an organic EL device. This device exhibited blue light emission with an emission luminance of 5000 (cd / m ² ) at 8V.

Example 107
Copper phthalocyanine was deposited on a glass plate with an ITO electrode to form a hole injection layer having a thickness of 25 nm. Next, the compound (6) and the compound (I) 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, (H) was vapor-deposited to form a 20 nm thick hole blocking layer. On top of that, Alq3 is further vacuum-deposited to form a 30 nm-thickness electron-injection-type light-emitting layer. On top of that, lithium fluoride is deposited to 1 nm and then Al is deposited to 200 nm to form an electrode. An EL element was obtained. When this device was driven at a constant current at a room temperature with an emission luminance of 500 (cd / m ² ), the luminance half life was 1000 hours or more.

  As described above, by using the compound having a carbazolyl group shown in the present invention, a high performance EL element can be produced. It is clear that remarkably high performance is exhibited with respect to the comparative compound, and it is possible to achieve a low driving voltage and a long life of the organic EL element.

FIG. 1 is ¹ H-NMR of the compound (1). (In heavy chloroform)

FIG. 2 is a ¹³ C-NMR of the compound (1). (In heavy chloroform)

FIG. 3 is a UV spectrum of the compound (1). (In toluene solvent)

FIG. 4 is a PL spectrum of the compound (1). (In toluene solvent)

Claims (9)

A compound having a carbazolyl group represented by the following general formula [1].
General formula [1]

(In the formula, A ¹ and A ² each independently represent a carbazolyl group represented by the following general formula [2], and R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group. And R ^{3 to} R ⁸ each independently represents a hydrogen atom, a halogen atom, or a monovalent organic residue.)
General formula [2]

(In the formula, Ar ¹ represents a monovalent aliphatic hydrocarbon group, a monovalent aromatic hydrocarbon group, or a monovalent aromatic heterocyclic group, and R ^{9 to} R ¹⁵ are each independently hydrogen. Represents an atom, a halogen atom, or a monovalent organic residue.) The compound having a carbazolyl group according to claim 1, wherein Ar ¹ is a monovalent aromatic hydrocarbon group. The compound having a carbazolyl group according to claim 1 or 2, wherein Ar ¹ is a phenyl group which may have a substituent represented by the following general formula [3].


General formula [3]

(Wherein R ^{16 to} R ²⁰ represent a hydrogen atom, a halogen atom, or a monovalent organic residue, and adjacent substituents may be bonded to form a new ring.) The compound having a carbazolyl group according to claim 1, wherein R ^{3 to} R ⁸ are hydrogen atoms. It R ⁹ to R ¹⁵ is claims 1 represents a hydrogen atom a compound having a carbazolyl group 4, wherein. The material for organic electroluminescent elements containing the compound which has a carbazolyl group of Claims 1-5. 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, wherein at least one layer of the light emitting layer contains the material for an organic electroluminescent element according to claim 6. An organic electroluminescence device. 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, wherein the light emitting layer comprises the organic electroluminescent element material according to claim 6. Luminescence element. 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, wherein the light emitting layer comprises a phosphorescent light emitting material and the material for an organic electroluminescent element according to claim 6. An organic electroluminescence device comprising the same.

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