JP2011012190A - Material for low molecular weight application type organic electroluminescent element, ink composition for organic electroluminescent element and organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic EL material film-formable by a wet film-forming method and hardly crystallizable.SOLUTION: The material for a low molecular application type organic electroluminescent element comprises a compound expressed by formula [1]. In the formula, A expresses a carbazolyl and each of R-Rexpresses aromatic hydrocarbon.

Description

  The present invention relates to a material used when an organic layer of an organic electroluminescence element (hereinafter abbreviated as an organic EL element) is formed by a wet film forming method such as coating. More specifically, when used in an organic EL device, the material can be formed by a wet film formation method such as a spin coating method, a cast method, or an ink jet method, and has excellent performance (high glass transition temperature, high light emission). In particular, the present invention relates to an organic EL element material, an organic EL element ink composition, and an organic EL element that can be used suitably for a blue light emitting material.

In recent years, an electroluminescent element (organic electroluminescent element) using an organic thin film has been developed. Examples of the method for forming the organic thin film include a vacuum deposition method and a wet film formation method. The wet film formation method does not require a vacuum process, and it is easy to increase the area, and there are advantages such as easy mixing of multiple materials with various functions in one layer (coating solution). An organic EL element in which an organic thin film layer is formed by a wet film forming method has been reported (see Patent Document 1).
The

  In addition, many known light-emitting low-molecular materials are hardly soluble, and the light-emitting layer is usually formed by vacuum deposition. However, the vacuum deposition method has a number of drawbacks such as a complicated process and the need for a large deposition apparatus. The luminescent low molecular weight material has an advantage that it can be purified with high purity by a known technique such as column chromatography as compared with the luminescent high molecular weight material. Therefore, a low-molecular material is less affected by impurities that are mixed therein, and thus may be a light-emitting material having higher light-emitting performance.

  As described above, it is expected that the light emitting layer can be made high quality, and the light emission efficiency of the organic EL element can be improved and the life can be extended. Therefore, it is desired to easily form a low molecular material by wet film formation. Has been.

  Regarding the technique of the ink composition for forming the light emitting layer of the organic EL device, there has already been reported an organic solvent. (See Patent Document 2)

  Moreover, as a low molecular light-emitting ink composition for organic EL elements used for forming a coating film, for example, an anthracene derivative has been reported. (See Patent Documents 3 and 4)

International Publication No. 03/037836 Pamphlet JP 2003-308969 A JP 2004-224766 A International Publication No. 06/070712

  In the organic EL device having a layer made of a low molecular material formed by a wet film formation method, the present invention is difficult to crystallize a layer made of a low molecular material (hereinafter sometimes referred to as a low molecular organic layer). It is an object to provide an organic EL element material and an organic EL element having excellent characteristics such as luminous efficiency, low voltage driving, high color purity, long life, and heat resistance. Another object of the present invention is to provide an ink composition for an organic EL device, which has a high solubility of a low-molecular material suitable for forming a layer constituting an organic light-emitting device and can be easily formed into a thin film by a wet process. Is to provide.

  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 material for a low molecular weight coating type organic electroluminescence device comprising a compound represented by the following general formula [1].

General formula [1]

(In the formula, A represents a carbazolyl group represented by the following general formula [2],
R ^{1 to} R ⁹ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted or unsubstituted Monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group, acyl group, alkoxy A carbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group is represented. )

General formula [2]

(In the formula, Ar ¹ represents a substituted or unsubstituted monovalent aromatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic heterocyclic group;
R ^{10 to} R ¹⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted or unsubstituted Monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group, acyl group, alkoxy A carbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group is represented. )

The present invention also relates to a material for a low molecular weight coating type organic electroluminescence device comprising R ⁵ is a substituted or unsubstituted phenyl group represented by the following general formula [3].

（式中、Ｒ¹⁷〜Ｒ²¹は、それぞれ独立に、水素原子、ハロゲン原子、置換もしくは未置換の１価の脂肪族炭化水素基、置換もしくは未置換の１価の芳香族炭化水素基、置換もしくは未置換の１価の脂肪族複素環基、置換もしくは未置換の１価の芳香族複素環基、シアノ基、アルコキシル基、アリ−ルオキシ基、アルキルチオ基、アリ−ルチオ基、置換アミノ基、アシル基、アルコキシカルボニル基、アリ−ルオキシカルボニル基、アルキルスルホニル基、または、アリ−ルスルホニル基を表し、Ｒ¹⁷〜Ｒ²¹は、それぞれ隣り合う置換基同士で環を形成しても良い。） General formula [3]

(Wherein R ^{17 to} R ²¹ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted Or an unsubstituted monovalent aliphatic heterocyclic group, a substituted or unsubstituted monovalent aromatic heterocyclic group, a cyano group, an alkoxyl group, an aryloxy group, an alkylthio group, an arylthio group, a substituted amino group, It represents an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group, and R ^{17 to} R ²¹ may each form a ring with adjacent substituents. )

  Moreover, this invention relates to the ink composition for organic electroluminescent elements containing the said low molecular coating type organic electroluminescent element material and a solvent.

  Further, the present invention provides an organic electroluminescent 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 wets the ink composition for an organic electroluminescent device. The present invention relates to an organic electroluminescence element which is a layer formed by a film forming method.

  Further, 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 wets the ink composition for an organic electroluminescence device. The present invention relates to an organic electroluminescence element which is a layer formed by a film forming method.

  Moreover, this invention relates to the said organic electroluminescent element in which a light emitting layer further contains a phosphorescence-emitting material.

  The organic EL element material of the present invention has very high heat resistance and is excellent in solubility in a solvent. By using this organic EL element material, it is possible to form a film that is hardly crystallized, has excellent thermal stability, and has excellent light emission characteristics by a wet film forming method. Moreover, since the organic EL element used as the organic EL element material according to the present invention is driven at a low voltage and has a long life, it can be suitably used as a flat panel display such as a wall-mounted television or a flat light emitter. It can be applied to light sources such as copiers and printers, light sources such as liquid crystal displays and instruments and lighting, display boards, and indicator lights, and has great technical value.

  Embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention, and the present invention does not exceed the gist thereof. It is not specified in the contents.

R ^{1 to} R ⁹ in the general formula [1] are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic hydrocarbon group. Substituted or unsubstituted monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group A group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group;

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

  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. Is mentioned.

  Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, 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 -C2-C18 alkenyl groups, such as an octadecenyl group, are mentioned.

  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 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-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, bipyridyl group, and monovalent aromatic heterocyclic group having 2 to 18 carbon atoms such phenanthrolyl group.

  Moreover, as an alkoxyl 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.

  Moreover, as an aryloxycarbonyl group, C2-C14 aryloxycarbonyl groups, such as a phenoxycarbonyl group and a naphthyloxycarbonyl group, are mentioned.

  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.

In these R ^{1 to} R ⁹ , the monovalent aliphatic hydrocarbon group, aromatic hydrocarbon group, aliphatic heterocyclic group, and aromatic heterocyclic group may be further substituted with other substituents. 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.

R ^{10 to} R ¹⁶ in the general formula [2] are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, or a substituted or unsubstituted monovalent aromatic hydrocarbon group. Substituted or unsubstituted monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group A group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, and an arylsulfonyl group;

In R ^{10 to} R ¹⁶ in the general formula [2], a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted or unsubstituted Monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group, acyl group, alkoxy The carbonyl group, aryloxycarbonyl group, alkylsulfonyl group, and arylsulfonyl group are each a halogen atom in R ^{1 to} R ⁹ , a substituted or unsubstituted monovalent aliphatic hydrocarbon group, substituted or Unsubstituted monovalent aromatic hydrocarbon group, substituted or unsubstituted monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group Ali - aryloxy group, an alkylthio group, ant - thio group, substituted amino group, an acyl group, an alkoxycarbonyl group, ant - Le oxycarbonyl group, an alkylsulfonyl group, and ants - is synonymous with Rusuruhoniru group.

Ar ¹ in the general formula [2] is a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted monovalent aromatic heterocyclic group having 2 to 18 carbon atoms. Represents. The monovalent aromatic hydrocarbon group and monovalent aromatic heterocyclic group referred to here are the monovalent aromatic hydrocarbon group and monovalent aromatic heterocyclic group in R ^{1 to} R ⁹ , and It is synonymous.

Preferable examples of R ⁵ in the general formula [1] include a substituted or unsubstituted monovalent aromatic hydrocarbon group having 10 to 18 carbon atoms, and more preferably a substituent represented by the general formula [3]. Or an unsubstituted phenyl group is mentioned.

From the viewpoint of further improving the solubility and the amorphousness, R ² in the general formula [1] is preferably a substituted or unsubstituted monovalent aliphatic hydrocarbon group having 1 to 18 carbon atoms or a general formula A substituted or unsubstituted phenyl group represented by [3], and more preferably, the substituent of the substituted or unsubstituted phenyl group represented by the general formula [3] has a substituent. May be a lower alkyl group such as a methyl group, an ethyl group, an n-propyl group, a 2-propyl group, an n-butyl group, an isobutyl group, or a tert-butyl group, and more preferably a methyl group. Group or ethyl group.

R ^{17 to} R ²¹ in the general formula [3] each independently represents a hydrogen atom, a halogen atom, or a monovalent organic residue.

Here, the halogen atom and the monovalent organic residue in R ^{17 to} R ^{21 have} the same meanings as the halogen atom and the monovalent organic residue in R ^{1 to} R ⁹ .

R ^{17 to} R ²¹ may form a ring with adjacent substituents. Specific examples thereof include a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, a 2-anthryl group, Examples include 5-anthryl group, 1-phenanthryl group, 9-phenanthryl group, and 1-acenaphthyl group.

Preferred examples of R ^{10 to} R ¹⁶ in the general formula [2] include a hydrogen atom, a monovalent aliphatic hydrocarbon group, and a monovalent aromatic hydrocarbon group. A more preferred example is a hydrogen atom. A monovalent aromatic hydrocarbon group is mentioned, A hydrogen atom is especially preferable.

  In the present invention, the wet film forming method is a coating method, an inkjet method, a dip coating method, a die coating method, a spray coating method, a spin coating method, a roll coater method, a dipping coating method, a screen printing method, flexographic printing, The composition is applied to form a film by a screen printing method, an LB method, or the like.

  As described above, the organic EL device material having an N-carbazolyl group represented by the general formula [1] of the present invention is a low molecular weight material, and its molecular weight is 4000 or less, preferably 3000 or less, more preferably. Is 2700 or less, particularly preferably 1800 or less, and usually 300 or more, preferably 450 or more, more preferably 550 or more. If the molecular weight exceeds the upper limit, purification may be difficult due to the high molecular weight of impurities, and if the molecular weight is lower than the lower limit, the glass transition temperature and melting point will decrease, so heat resistance may be significantly impaired. There is sex.

  Although the typical example of the low molecular application type organic EL element material of this invention is shown in the following Table 1, this invention is not limited to this representative example.

Table 1

  The organic EL device material 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 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 device material is particularly preferably used.

  When used as a material for an organic EL device, a high-purity material is required, but the compound having a carbazolyl group of the present invention is a sublimation purification method, recrystallization method, reprecipitation method, zone melting method, column purification. Method, adsorption method, etc., or a combination of these methods. 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.

  Next, the ink composition for organic EL elements will be described.

  The ink composition for organic EL elements to which this embodiment is applied contains at least the material for organic EL elements of the present invention and a solvent.

  Various solvents are applicable as the solvent contained in the above-mentioned ink composition for organic EL elements, and are not particularly limited. For example, aromatic hydrocarbons such as toluene, xylene, methicylene, cyclohexylbenzene and tetralin; halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene and trichlorobenzene; 1,2-dimethoxybenzene, 1,3-dimethoxybenzene and anisole , Phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole and other aromatic ethers; phenyl acetate, phenyl propionate, methyl benzoate, benzoic acid Aromatic esters such as ethyl, propyl benzoate and n-butyl benzoate; ketones having an alicyclic ring such as cyclohexanone and cyclooctanone; aliphatic ketones such as methyl ethyl ketone and dibutyl ketone; methyl ethyl ketone and cyclohexano Alcohol having an alicyclic ring such as ruthenium or cyclooctanol; Aliphatic alcohol such as butanol or hexanol; Aliphatic ether such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether or propylene glycol-1-monomethyl ether acetate (PGMEA); Ethyl acetate And aliphatic esters such as n-butyl acetate, ethyl lactate and n-butyl lactate.

  Of these, aromatic hydrocarbons such as toluene, xylene, methicylene, cyclohexylbenzene, tetralin and the like are preferable in that they have low water solubility and are not easily altered.

  These solvents may be used alone or in combination. In addition, the solvent which can be used is not limited to these.

  Since organic electroluminescent devices use many materials such as cathodes that deteriorate significantly due to moisture, the presence of moisture in the composition causes moisture to remain in the dried film, degrading the device characteristics. The possibility is considered and it is not preferable.

  Further, in order to reduce a decrease in film formation stability due to solvent evaporation from the composition during wet film formation, the boiling point is 100 ° C. or higher, preferably 150 ° C. as the solvent of the composition for organic EL elements. As described above, it is more effective to use a solvent having a boiling point of 200 ° C. or higher.

  The ink composition for an organic EL element of the present invention is preferably used for an organic EL light emitting element in which a light emitting material is a low molecular material and a layer containing the light emitting material is formed by a wet film forming method.

  The composition for an organic EL device of the present invention is mainly used for containing a light emitting material and forming a light emitting layer, but may be used for other layers such as a hole transport layer.

  In the present invention, as long as the object of the present invention is not impaired, if desired, the ink composition of the present invention may contain other known luminescent materials in the light emitting layer. A light-emitting layer containing another known light-emitting material may be stacked on the light-emitting layer formed by a wet film formation method. In this case, the light emitting layer containing another known light emitting material may be formed by a dry method such as a vacuum evaporation method.

  In general, the organic EL element is manufactured on a light-transmitting substrate. The translucent substrate referred to here is a substrate that supports the organic EL element, and is preferably a smooth substrate having a light transmittance in the visible region of 400 to 700 nm of 50% or more.

  Specifically, a glass plate, a polymer plate, etc. are mentioned. 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 polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone.

  In the organic EL element ink composition of the present invention, the content of the organic EL element material of the present invention is preferably 0.5 wt% or more. Usually, the thickness of the light-emitting layer of the organic EL element is 10 to 100 nm, but generally it is often 50 nm or more. When the film thickness is less than 50 nm, problems such as a decrease in light emission performance and a large color tone deviation occur. In order to easily form a film thickness of 50 nm or more, the solution concentration is preferably 0.5 wt% or more. When the concentration is lower than 0.5 wt%, it is difficult to form a thick film.

  In addition to the organic EL element material and solvent described above, a known additive may be added to the ink composition for an organic EL element of the present invention as necessary.

  The luminescent ink composition for organic EL devices of the present invention is a known wet film forming method, for example, coating method, ink jet method, dip coating method, die coating method, spray coating method, spin coating method, roll coater method, dipping method. A film can be formed by a coating method, screen printing method, flexographic printing, screen printing method, LB method, or the like.

  Here, the organic EL element which can be produced using the ink composition for organic EL elements 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. Further, an interlayer that is adjacent to the light emitting layer between the light emitting layer and the anode and has a role of separating the light emitting layer and the anode or the light emitting layer from the hole injection layer or the hole transport layer. Layers may be inserted. 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) Anode / light emitting layer / hole blocking layer / electron injection layer / cathode, (8) anode / light emitting layer / electron injection layer / cathode, etc. (9) Anode / hole injection layer / hole transport layer / interlayer layer / light emission Layer / cathode, (10) anode / hole injection layer / interlayer layer / light emitting layer / electron injection layer / cathode, (11) anode / hole injection layer / hole transport layer / in Chromatography / light-emitting layer / electron injection layer / cathode, it is considered elements formed by laminating a multilayer structure of.

  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 There is a method of laminating a plurality of portions.

  The material for an organic EL device of the present invention may be used for any of the above-described layers, but can be suitably used as a light emitting layer material particularly when producing a blue light emitting device. Further, 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, by mixing and laminating. Furthermore, in the light emitting layer mentioned above, you may use with another 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 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 (Japanese Unexamined Patent Publication No. 2-282263), Japanese Unexamined Patent Publication No. 1-211399, conductive polymer oligomers (especially thiophene oligomers), polyethylene dioxythiophene / polysulfonic acid (PEDOT / PSS), etc. Can do.

  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.

Further, materials that can be used for the hole injection layer include molybdenum oxide (MnO _x ), vanadium oxide (VO _x ), ruthenium oxide (RuO _x ), copper oxide (CuO _x ), tungsten oxide (WO _x ), and iridium oxide. Inorganic oxides such as (IrO _x ) are also included.

  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 preferred examples of the hole injection material are shown in Table 2.

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

  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.

  Examples of the material used for the interlayer layer include polymers containing aromatic amines such as polyvinylcarbazole and derivatives thereof, polyarylene derivatives having aromatic amines in the side chain or main chain, arylamine derivatives, and triphenyldiamine derivatives. In addition, as a method for forming the interlayer layer, when a high molecular weight material is used, a method by film formation from a solution is exemplified.

  For the formation of an interlayer layer from a solution, a known wet film forming method, for example, a spin coating method, a casting method, a micro gravure coating method, a gravure coating method, a bar coating method, a roll coating method, a wire bar coating method, Coating methods such as a dip coating method, a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, an ink jet printing method, a capillary coating method, and a nozzle coating method can be used.

  The thickness of the interlayer layer varies depending on the material to be used, and may be selected so that the driving voltage and the light emission efficiency are appropriate values. Usually, the thickness is 1 nm to 1 μm, preferably 2 to 500 nm. More preferably, it is 5-200 nm.

  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, polyquinoline and its derivatives, polyquinoxaline and its derivatives, polyfluorene and its 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.

  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.

  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.

  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).

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

  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 [ 6] to those having the structure of the general formula [8].

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-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 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.

  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 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 11 elements are targeted. Specific examples include iridium, platinum, and copper. 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 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 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 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 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 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 Table 2002-53482, S.I. T. T. et al. 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.

  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).

  Examples of the main method of full colorization of the organic EL device 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. T. et al. 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 element using the organic electroluminescent element-containing material having a carbazolyl group of the present invention can obtain long-term blue light emission with 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.

  First, a synthesis example of the organic EL element material of the present invention is shown.

Synthesis example 1
Method for synthesizing compound (1)

  Compound (1) was synthesized according to Reaction 1 to Reaction 4.

Reaction 1

  Hereinafter, the synthesis method will be described with reference to Reaction 1. Under nitrogen atmosphere at −78 ° C., 9.63 g (0.03 mol) of 3-bromo-9-phenylcarbazole (I) and 33 ml of n-butyllithium (1.52 M hexane solution) in tetrahydrofuran (100 ml). The reaction was carried out to lithiate the 3-position of 3-bromo-9-phenylcarbazole. After stirring for 2 hours, 10.39 g (0.1 mol) of trimethyl borate was slowly added dropwise at −78 ° C., stirred at the same temperature for 2 hours, and further stirred at room temperature for 3 hours. Thereafter, 200 ml of 1% aqueous hydrochloric acid solution was added to the reaction product, stirred for 30 minutes, neutralized with 1% aqueous sodium hydroxide solution, extracted with ether, dried, concentrated with an evaporator, and 8.65 g of 9-phenyl. Carbazole-3-boronic acid (II) was obtained.

Reaction 2

  Hereinafter, the synthesis method will be described with reference to Reaction 2. Under a nitrogen atmosphere, (III) 10.38 g (0.04 mol), (IV) 10.0 g (0.05 mol), tetrakis (triphenylphosphine) palladium 0.3 g, potassium carbonate (2M aqueous solution) 50 g, tetrahydrofuran 50 g Was added to 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 in a hot vacuum to obtain 12 g of (V) as a crude product. Purified by chromatography.

Reaction 3

Hereinafter, the synthesis method will be described with reference to Reaction 3. Under a nitrogen atmosphere, 10 g (0.033 mol) of (V) and 130 ml of carbon tetrachloride were added into a three-necked flask, and 5.8 g (0.033 mol) of bromine and 10 ml of carbon tetrachloride were slowly added using a dropping funnel. Dripping.
After completion of the dropwise addition, the mixture is stirred at room temperature for 1 hour, and then the reaction is terminated with an aqueous sodium thiosulfate solution. Thereafter, the organic layer was neutralized, washed with water, and the solvent was removed with an evaporator. 9.5g of compound (VI) was obtained by recrystallizing the obtained yellow powder with toluene.

Reaction 4

Hereinafter, the synthesis method will be described with reference to Reaction 4. Under a nitrogen atmosphere, 4.09 g (0.01 mol) of (VI), 3.00 g (0.012 mol) of (II), 0.3 g of tetrakis (triphenylphosphine) palladium, 50 g of potassium carbonate (2M aqueous solution), 50 g of tetrahydrofuran Was added to 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 in a hot vacuum to obtain 3.20 g of (compound (1)) as a crude product. The obtained crude product was purified by silica gel column chromatography, and further sublimation purification was performed. Compound (1) was identified by mass spectrum (manufactured by Bruker Daltonics, Autoflex II), ¹ H-NMR, and ¹³ C-NMR (manufactured by JEOL, ECX-400P). The UV spectrum and fluorescence (PL) spectrum of the compound (1) are shown in FIGS. The UV spectrum was measured with a photometer (U-3500) manufactured by Hitachi Spectro Co., Ltd., and the fluorescence (PL) spectrum was measured with a fluorescence spectrophotometer (FP-6500) manufactured by JASCO Corporation.

  The 3-bromo-9-phenylcarbazole (I) used for the synthesis of compound (1) was synthesized according to the method described in WO2007 / 43484. Commercially available reagents were used for 4-biphenylboronic acid (II) and 9-bromoanthracene (III).

Synthesis Examples 2 to 30
The synthesis method combined the following reactions 5 to 10 to synthesize the compounds in Table 1.

Reaction 5

R ^{22 to} R ²⁶ 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 (VII) with n-butyllithium (n-BuLi) at -78 ° 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 (VIII) form.

Reaction 6

R ^{1 to} R ⁹ 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. R ^{22 to} R ²⁶ have the same meanings as described above. As a synthesis method, the target compound is obtained by performing the same operation as in Synthesis Example 1 except that the carbazole derivative (VIII) is equivalently reacted with the 9-bromoanthracene derivative (IX).

Reaction 7

R ^{10 to} R ¹⁶ 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 has the same meaning as described above. As the synthesis method, except that the equivalent reaction of 9-bromoanthracene derivative (IX) corresponding to (III) instead of (III) of Synthesis Example 1 and carbazole derivative (XI) corresponding to (II) instead of (II) is carried out. The target compound (XII) was obtained by the same operation as in Example 1.

Reaction 8

R ^{17 to} R ²¹ are as defined above. As the synthesis method, Example 9 was carried out except that the equivalent reaction of 9-bromoanthracene derivative (XIII) corresponding to (III) instead of (III) and the corresponding benzene derivative (XIV) instead of (II) was carried out. The target compound (XV) was obtained by carrying out the same operations as in.

Reaction 9

R ^{17 to} R ²¹ are substituents necessary for synthesizing the compound of the present invention. As a synthesis method, bromination was performed according to a conventional method using bromine or NBS, using the corresponding anthracene derivative (XIX) instead of (IV) in Example 1.

Reaction 10

R ^{15 to} R ²¹ 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 has the same meaning as described above. As the synthesis method, Example 9 was carried out except that equivalent reaction of 9-bromoanthracene derivative (XX) corresponding to (III) instead of (III) and equivalent carbazole derivative (XXI) instead of (II) was performed. The target compound (XXII) was obtained by the same operation as in Example 1.

  The structure of the compound of the present invention obtained by combining the above reactions 1 to 10 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.

  Hereinafter, although the following Example demonstrates the ink composition for organic EL elements of this invention, this invention is not limited to the following Example.

Example 51
Solubility measurement of compound (1)

  The solubility of the compound (1) of the present invention in toluene was examined, and the results are shown in Table 8. As shown in Table 1, the compound (1) showed sufficient solubility for film formation in toluene.

Examples 52-100
Table 8 shows the results of examining the solubility in toluene using the compounds shown in Table 1 instead of the compound (1).

Comparative Example 1
The solubility in toluene was examined using the compound (A) shown below. The results are shown in Table 8.

Hereinafter, although the organic EL element which used the compound of this invention as an organic EL element material is demonstrated by the following example, this invention is not limited to the following example. 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 spin coating was rotated for 1 minute at a rotational speed between 500 rpm and 2500 rpm in accordance with the solvent type and the target film thickness. The light emission characteristics of the element were measured using an organic EL element having a light emitting element area of 2 mm × 2 mm.

Example 101
On the washed glass plate with an ITO electrode, HTM5 of Table 3 was vacuum-deposited to obtain a hole injection layer having a thickness of 60 nm. Subsequently, the toluene solution (concentration: 2 wt%) of the compound (1) in Table 1 of the present invention was spin-coated, and then dried under reduced pressure at 70 ° C. for 1 hour to obtain a light emitting layer having a thickness of 50 nm. Furthermore, tris (8-hydroxyquinolino) aluminum complex (Alq3) was vacuum-deposited to form an electron injection layer having a thickness of 20 nm, on which 1 nm of lithium fluoride and then 150 nm of aluminum (Al) were deposited. Thus, an electrode was formed to obtain an organic EL element. The chromaticity when this device was driven to 6 V was blue light emission of CIE (x, y) = (0.14, 0.04). 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. In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 9.

Examples 102-126
A device was prepared in the same manner as in Example 101 except that a light emitting layer was prepared using the compounds shown in Table 1 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 15 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 9.

Comparative Example 2
A device was produced in the same manner as in Example 101 except that a light emitting layer was produced using the compound (A) shown above. The chromaticity when this device was driven to 6 V was blue light emission of CIE (x, y) = (0.08, 0.03). 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 ). In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 9.

  As is apparent from Table 9, all the compounds of the present invention had a longer lifetime and higher luminance than the device prepared in Comparative Example 2.

Example 127
HIM3 in Table 2 was dissolved in toluene at a concentration of 2% by weight, and a hole injection layer having a thickness of 70 nm was formed on a glass plate with an ITO electrode by spin coating using the obtained solution. Next, the compound (1) and the compound (B) in Table 1 are dissolved in xylene at a weight ratio of 5: 100 to prepare a 1.5 wt% solution, and spin coating is performed using the obtained solution. A light emitting layer having a thickness of 40 nm was formed. Further, Compound EX5 in Table 4 was dissolved in toluene at a concentration of 2% by weight, and an electron injection layer having a thickness of 20 nm was formed by spin coating using the obtained solution. 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. When this device was driven at a direct current of 10 V, the external quantum efficiency was 4.6%. Further, the luminance half life when driving at constant current with emission luminance of 500 (cd / m ² ) was measured. Further, the initial luminance when driven at a current density of 13.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 10.

Examples 128-152
A device was prepared in the same manner as in Example 127 except that the compounds in Table 10 were used instead of the compound (1). All of these devices exhibited an external quantum efficiency of 4% or more at a DC voltage of 10V. Further, the luminance half life when driving at constant current with emission luminance of 500 (cd / m ² ) was measured. In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 10.

Comparative Example 3
A device was prepared in the same manner as in Example 127 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 with an emission luminance of 500 (cd / m ² ) was measured. In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 10.

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 device prepared in Comparative Example 3.

Example 153
HIM4 in Table 2 was dissolved in toluene at a concentration of 2% by weight, and a hole injection layer having a film thickness of 70 nm was formed on the glass plate with an ITO electrode by spin coating using the obtained solution. Next, the compound (1) and the compound (C) in Table 1 were dissolved in chloroform at a weight ratio of 3: 100 to prepare a 3% by weight solution, and the film thickness was obtained by spin coating using the obtained solution. A 40 nm light emitting layer was formed. Further, Alq3 was deposited to form an electron injection layer having a thickness of 20 nm. On top of this, 1 nm of lithium fluoride (LiF) and 100 nm of Al were further evaporated to form a cathode to obtain an organic EL device. When this device was driven at a direct current of 10 V, the external quantum efficiency was 4.6%. Further, the luminance half life when driving at constant current with emission luminance of 500 (cd / m ² ) was measured. Further, the initial luminance when driven at a current density of 13.5 mA / cm ² and the luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 11.

Examples 154-165
A device was prepared in the same manner as in Example 153 except that the compound in Table 11 was used instead of the compound (1). All of these devices exhibited an external quantum efficiency of 4% or more at a DC voltage of 10V. Further, the luminance half life when driving at constant current with emission luminance of 500 (cd / m ² ) was measured. In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 11.

Table 11

  As is apparent from Table 11, all the compounds of the present invention have a long lifetime and high brightness.

Example 166
A film of poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (manufactured by HC Starck, trade name: CLEVIOS P CH8000) was formed on a cleaned glass plate with an ITO electrode by a spin coating method. A hole injection layer having a thickness of 80 nm was obtained. Next, the compound (B) and the compound (1) are dissolved in isopropyl alcohol at a weight ratio of 100: 3 to prepare a 1 wt% solution, and the film thickness of 30 nm is formed by spin coating using the obtained solution. A light emitting layer was formed. Further, the compound (D) was dissolved in toluene at a concentration of 2% by weight, and an electron injection layer having a thickness of 30 nm was formed by spin coating using the obtained solution. 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 3.7% at a DC voltage of 10V. Further, the luminance half life when driving at constant current with emission luminance of 500 (cd / m ² ) was measured. In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 12.

Examples 167-186
A device was prepared in the same manner as in Example 166 except that the compounds in Table 10 were used instead of the compound (1). Each of these elements exhibited an external quantum efficiency of 3% or more at a DC voltage of 10 V, and the luminance half-life when the device was driven at a constant current at an emission luminance of 500 (cd / m ² ) was measured. In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 12.

Comparative Example 4
A device was prepared in the same manner as in Example 166 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 with an emission luminance of 500 (cd / m ² ) was measured. In addition, initial luminance when driven at a current density of 12.5 mA / cm ² and luminance after continuous driving for 100 hours in an environment of 80 ° C. were measured. The results are shown in Table 12.

Table 12

  As is clear from Table 12, all the compounds of the present invention had a longer lifetime and higher luminance than the device prepared in Comparative Example 4.

Example 187
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. Next, the compound (2) in Table 1 of the present invention was dissolved in toluene at a concentration of 2% by weight, and an electron transporting light emitting layer having a film thickness of 60 nm was obtained by spin coating using the obtained solution. 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 element showed blue light emission with an emission luminance of 2200 (cd / m ² ) at 8V.

Example 188
On the glass plate with an ITO electrode, HIM2 was vapor-deposited to form a 65 nm-thick hole injection layer. Next, the compound (2) and the compound (E) in Table 1 were dissolved in acetone at a weight ratio of 100: 3 to prepare a 1 wt% solution, and the film thickness was obtained by spin coating using the obtained solution. A 45 nm light emitting layer was formed. Furthermore, ES2 of Table 6 was vapor-deposited to form an electron transport layer having a thickness of 20 nm. Furthermore, Alq3 is further vacuum-deposited to form an electron injection layer having a thickness of 10 nm, and then an electrode is formed by first depositing 1 nm of lithium fluoride and then 200 nm of Al to form an electrode. Got. 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.

Example 189
Compound (5) was dissolved in toluene at a concentration of 2% by weight on a glass plate with an ITO electrode, and a hole injection layer having a film thickness of 65 nm was formed by spin coating using the resulting solution. Next, the compound (B) was deposited to form a 45 nm light emitting layer. Furthermore, Alq3 was vacuum-deposited to form an electron transport layer having a thickness of 20 nm, and then an electrode was formed thereon by first depositing lithium fluoride at 1 nm and then Al at 200 nm to obtain an organic EL device. 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.

Example 190
A film of poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (manufactured by HC Starck, trade name: CLEVIOS P CH8000) was formed 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 (27), 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. Furthermore, after depositing 20 nm of Ca thereon, 200 nm of Al was deposited to form an electrode to obtain an organic EL device. When this device was subjected to an energization test, blue light emission with a maximum light emission luminance of 750 cd / m ² was obtained.

Example 191
A film of poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (manufactured by HC Starck, trade name: CLEVIOS P AI4083) was formed 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 (40) and 37% of electron transport material (compound (G)) 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 20 nm of Ca thereon, 200 nm of Al was deposited to form an electrode to obtain an organic EL device. When this device was subjected to an energization test, blue light emission with a maximum light emission luminance of 640 cd / m ² was obtained.

Example 192
On a glass plate with an ITO electrode, poly (3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (manufactured by HC Starck, trade name: CLEVIOS P AI4083) was spin-coated to form a 65 nm hole injection layer. Obtained. Next, the compound (H) was dissolved in xylene at a concentration of 0.5% by weight, and an interlayer layer having a thickness of 10 nm was formed by spin coating using the obtained xylene solution. Subsequently, the compound (1) in Table 1 was dissolved in toluene at a concentration of 2% by weight, and a 60 nm light-emitting layer was obtained by spin coating using the obtained solution. 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 EL device. When this device was driven at a direct current of 10 V, blue light emission with an external quantum efficiency of 4.6% and a maximum light emission luminance of 710 cd / m ² was obtained.

  Here, the compound (H) is a random copolymer in which two repeating units represented by the following formula are constituted at a molar ratio of 50:50.

  (In the formula, n represents an integer of 3 to 500.)

Example 193
A polymer material (product number: ADS254BE manufactured by Sigma-Aldrich) was dissolved in toluene at a concentration of 2% by weight, and a hole injection layer having a film thickness of 65 nm was spin coated on the glass substrate with ITO using the obtained solution. I got it. Next, the compound (1) in Table 1 was dissolved in toluene at a concentration of 2% by weight, and a 60 nm light emitting layer was obtained by spin coating using the obtained solution. 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 EL device. When this device was subjected to an energization test, blue light emission with a maximum light emission luminance of 640 cd / m ² was obtained.

  As described above, a high-performance EL element can be produced by using the organic EL element material shown in the present invention. It is clear that remarkably high performance is exhibited with respect to the comparative compound, and high emission efficiency, low drive voltage, long life, and high color purity blue light emission of the organic EL element can be achieved.

Claims (6)

A material for a low molecular weight coating type organic electroluminescence device comprising a compound represented by the following general formula [1].
General formula [1]

(In the formula, A represents a carbazolyl group represented by the following general formula [2],
R ^{1 to} R ⁹ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted or unsubstituted Monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group, acyl group, alkoxy A carbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group is represented. )
General formula [2]

(In the formula, Ar ¹ represents a substituted or unsubstituted monovalent aromatic hydrocarbon group or a substituted or unsubstituted monovalent aromatic heterocyclic group;
R ^{10 to} R ¹⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted or unsubstituted Monovalent aliphatic heterocyclic group, substituted or unsubstituted monovalent aromatic heterocyclic group, cyano group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, substituted amino group, acyl group, alkoxy A carbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group is represented. ) The material for a low molecular weight coating type organic electroluminescence device according to claim 1, wherein R ⁵ is a substituted or unsubstituted phenyl group represented by the following general formula [3].
General formula [3]

(Wherein R ^{17 to} R ²¹ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted monovalent aliphatic hydrocarbon group, a substituted or unsubstituted monovalent aromatic hydrocarbon group, a substituted Or an unsubstituted monovalent aliphatic heterocyclic group, a substituted or unsubstituted monovalent aromatic heterocyclic group, a cyano group, an alkoxyl group, an aryloxy group, an alkylthio group, an arylthio group, a substituted amino group, It represents an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group, and R ^{17 to} R ²¹ may each form a ring with adjacent substituents. )   The ink composition for organic electroluminescent elements containing the low molecular application type organic electroluminescent element material and solvent of Claim 1 or 2.   4. An organic electroluminescence device comprising a plurality of organic layers including a light emitting layer formed between a pair of electrodes, wherein at least one of the organic layers is a wet film-forming ink composition for an organic electroluminescence device according to claim 3. An organic electroluminescence element which is a layer formed by a method.   4. An organic electroluminescent device comprising a light emitting layer or a plurality of organic layers including a light emitting layer formed between a pair of electrodes, wherein the light emitting layer is a wet film-forming ink composition for an organic electroluminescent device according to claim 3. An organic electroluminescence element which is a layer formed by a method.   The organic electroluminescent element according to claim 4 or 5, wherein the light emitting layer further comprises a phosphorescent light emitting material.