KR20170066307A - Charge-transporting varnish - Google Patents

Abstract

[식 중, R¹∼R⁸은, 서로 독립하여, 수소 원자 등을 나타내고, Ar¹은 페닐기 등을 나타내고, n은 1∼3의 정수를 나타내고, X는 식 (2a) 또는 (2b)로 표시되는 2가의 유기기를 나타낸다.

(식 중, R⁹ 및 R¹⁰은, 서로 독립하여, 탄소수 1∼20의 알킬기 등을 나타내고, R¹¹ 및 R¹²는, 서로 독립하여, 수소 원자 또는 불소 원자를 나타내고, R¹³∼R²⁰은, 서로 독립하여, 수소 원자 등을 나타내고, m은 1∼4의 정수를 나타낸다.)]The charge-transporting material comprising an arylamine derivative represented by the formula (1) shows good solubility in an organic solvent. When a thin film prepared from a charge-transporting varnish containing the charge-transporting material is applied to a hole-injecting layer, Can be realized.

Wherein Ar ¹ represents a phenyl group or the like, n represents an integer of 1 to 3, and X represents a group represented by the formula (2a) or (2b): wherein R ¹ to R ⁸ are independently of each other a hydrogen atom, Represents a divalent organic group to be represented.

(Wherein R ⁹ and R ¹⁰ are independently of each other an alkyl group having 1 to 20 carbon atoms and the like, R ¹¹ and R ¹² are each independently a hydrogen atom or a fluorine atom, and R ¹³ to R ²⁰ are , Independently of each other, represent a hydrogen atom or the like, and m represents an integer of 1 to 4))]

Description

{CHARGE-TRANSPORTING VARNISH}

The present invention relates to a charge transport varnish.

In organic electroluminescence (hereinafter referred to as organic EL) elements, a charge transporting thin film made of an organic compound is used as a light emitting layer or a charge injecting layer. In particular, the hole injecting layer carries out charge transfer between the anode, the hole transporting layer, or the light emitting layer, and performs an important function for achieving low voltage driving and high luminance of the organic EL element.

A method of forming a charge-transporting thin film is roughly divided into a dry process represented by a vapor deposition method and a wet process represented by a spin coating method. Comparing these processes, a wet process can efficiently produce a thin film having a large flatness . For this reason, a hole injection layer capable of being formed by a wet process has been demanded at present as the organic EL display is being made larger.

However, there are many problems that are not solved in the initial characteristics and lifetime characteristics of the organic EL device and the manufacturing process thereof. In order to solve these various problems, various studies have been made on a material for forming a functional thin film for an organic EL device. As a part of this, a charge-transporting material having a hole injecting property has been studied.

An arylbenzidine derivative is known as a charge-transporting substance having a hole injecting property. For example, tetraarylbenzidine as an arylbenzidine derivative is crosslinked with a fluorene structure or a cyclohexane structure as a charge-transporting substance (see, for example, Patent Documents 1 to 5).

However, an example of a charge-transporting material using a crosslinked product of an arylbenzidine derivative in which both nitrogen atoms have a bond with a hydrogen atom has not yet been confirmed.

European Patent Application Publication No. 2684932 International Publication No. 2013/022419 International Publication No. 2014/009310 Japanese Patent Application Laid-Open No. 2002-179630 European Patent Application Publication No. 650955

The present invention has been made in view of the above circumstances and provides a new charge-transporting material excellent in hole injection property, a charge transporting varnish containing the same, a charge transporting thin film obtained from the varnish, a method for producing the same, and an organic EL device having the thin film .

DISCLOSURE OF THE INVENTION The inventors of the present invention have made intensive investigations in order to achieve the above object and as a result have found that a desired arylamine derivative having a biphenylamine structure has excellent solubility in an organic solvent and dissolves it in an organic solvent, It has been found that a thin film exhibiting transportability can be obtained and a device having excellent luminance characteristics can be obtained when the thin film is applied to a hole injection layer of an organic EL device.

That is,

1. A charge-transporting material characterized by comprising an arylamine derivative represented by the formula (1)

[Wherein, R ¹ ~R ⁸ are, independent from each other, represents a hydrogen atom, a halogen atom, or Z ^1, which may be substituted with an alkyl or alkoxy of 1 to 20 carbon atoms having 1 to 20 carbon atoms, Ar ¹ is substituted by Z ² may represent is an aryl having a carbon number of 6~20, n represents an integer of 1~3, X denotes a divalent organic group represented by the formula (2a) or (2b),

(Wherein R ⁹ and R ¹⁰ are independently of each other an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms which may be substituted with Z ² , or R ⁹ And R ¹⁰ represents a cyclic hydrocarbon group which may be condensed to have 3 to 21 carbon atoms and R ¹¹ and R ¹² independently represent a hydrogen atom or a fluorine atom and R ¹³ to R ²⁰ may be mutually independent A hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, or Z ³ , and m represents an integer of 1 to 4).

Z ¹ is a halogen atom, a group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, a sulfonic acid group, a carboxylic acid group, or an aryl group of 6 to 20 carbon atoms optionally substituted by Z ³ or a C2-nitro represents a heteroaryl group of ~20, Z ² is a halogen atom, a nitro group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, a sulfonic acid group, a carboxylic acid group, having 1 that may be substituted by Z ³ or An alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 20 carbon atoms; Z ³ represents a halogen atom, a nitro group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, , Or a carboxylic acid group.

2. One charge-transporting material selected from the bivalent organic groups represented by formulas (3a) to (3h)

3. A charge-transporting material comprising 1 or 2 charge-transporting materials,

4. One or two charge-transporting substances, a charge-transporting varnish comprising an organic solvent,

5. A charge transporting varnish of 4, further comprising a dopant material,

6. The charge transporting varnish of claim 5 wherein the dopant material comprises a heteropoly acid,

7. A charge-transporting thin film produced by using any one of the charge-transporting varnishes 4 to 6,

8. An organic electroluminescence device having a charge transporting thin film,

9. A process for producing a charge-transporting thin film, characterized in that any one of charge-transporting varnishes 4 to 6 is applied on a substrate and the solvent is evaporated

.

The arylamine derivative as a charge-transporting material of the present invention is easily dissolved in an organic solvent and can be easily dissolved in an organic solvent together with a dopant to prepare a charge-transporting varnish.

The thin film produced from the charge transporting varnish of the present invention exhibits high charge transportability and can therefore be suitably used as a thin film for an electronic device including an organic EL device. In particular, by applying this thin film to the hole injection layer of the organic EL device, an organic EL device having excellent luminance characteristics can be obtained.

Further, since the charge transporting varnish of the present invention can produce a thin film having excellent charge transportability with good reproducibility even when various wet processes such as the spin coating method and the slit coating method are used, It can cope with the progress of

The thin film obtained from the charge transporting varnish of the present invention can also be used as an antistatic film or a positive electrode buffer layer of an organic thin film solar cell.

Hereinafter, the present invention will be described in more detail.

The charge-transporting material according to the present invention is composed of the arylamine derivative represented by the formula (1).

Here, charge transportability has the same meaning as conductivity and has the same meaning as hole transportability. The charge-transporting material may have a charge-transporting property itself, or may have charge-transporting property when used together with a dopant material. The charge transporting varnish may have charge transporting property itself, and the solid film obtained thereby may have charge transporting property.

In formula (1), R ¹ to R ⁸ independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, which may be substituted with Z ¹ .

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

Specific examples of the alkyl group having 1 to 20 carbon atoms may be linear, branched or cyclic, and examples thereof include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, A straight chain or branched chain alkyl group having 1 to 20 carbon atoms such as a butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, ; A cyclohexyl group, a bicyclohexyl group, a bicyclohexyl group, a cyclohexyl group, a cyclohexyl group, a cyclohexyl group, a cyclohexyl group, a cyclohexyl group, a cyclopentyl group, A cyclic alkyl group having 3 to 20 carbon atoms such as a cyclopentyl group, a cyclopentyl group, a cyclopentyl group, a cyclopentyl group, a cyclopentyl group, a cyclopentyl group, a cyclopentyl group, a cyclopentyl group,

As specific examples of the alkoxy group having 1 to 20 carbon atoms, the alkyl group in the alkyl group may be any of linear, branched and cyclic. Examples thereof include methoxy, ethoxy, n-propoxy, N-butoxy group, n-butoxy group, n-pentyloxy group, 1-methyl-n-butoxy group, 2-methyl-n-butyloxy group, N-butoxy group, a 1,1-dimethyl-n-propoxy group, a c-pentyloxy group, a 2-methyl- methyl-n-pentyloxy group, 1,1-dimethyl-n-butoxy group, 1-ethyl-n-butoxy group, 1,1,2- Butoxy group, n-heptyloxy group, n-octyloxy group, n-hexyloxy group, n-hexyloxy group, N-nonyloxy group, and n-decyloxy group.

Ar ¹ represents an aryl group having 6 to 20 carbon atoms which may be substituted with Z ² .

Specific examples of the aryl group having 6 to 20 carbon atoms include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, a 2-anthryl group, a 9-anthryl group, a 1-phenanthryl group, Group, a 3-phenanthryl group, a 4-phenanthryl group, and a 9-phenanthryl group.

n represents an integer of 1 to 3, preferably 1.

X represents a divalent organic group represented by the formula (2a) or (2b).

R ⁹ and R ¹⁰ independently of each other represent an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ² , or R ⁹ and R ¹⁰ , R ¹¹ and R ¹² independently represent a hydrogen atom or a fluorine atom and R ¹³ to R ²⁰ independently represent a hydrogen atom or a hydrocarbon group having ¹ to ²⁰ carbon atoms, , An alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, or Z ³ .

Examples of the alkyl group having 1 to 20 carbon atoms and the aryl group having 6 to 20 carbon atoms include the same groups as described above.

Specific examples of the fluoroalkyl group having 1 to 20 carbon atoms may be any of linear, branched and cyclic, and examples thereof include a trifluoromethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethyl group, Fluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, 2,2,3,3-tetrafluoropropyl group, 2,2,2-trifluoro-1- (trifluoro Nonyl fluoroethyl group, non-fluorobutyl group, 4,4,4-trifluorobutyl group, undecafluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoro 2,2,3,3,4,4,5,5-octafluoropentyl group, tridecafluorohexyl group, 2,2,3,3,4,4,5,5,6 , 6,6-undecafluorohexyl group, 2,2,3,3,4,4,5,5,6,6-decafluorohexyl group, 3,3,4,4,5,5, 6,6-nonafluorohexyl group, and the like.

m represents an integer of 1 to 4, but is preferably 1.

Examples of the cyclic hydrocarbon group having 3 to 21 carbon atoms which may be condensed and formed by combining R ⁹ and R ¹⁰ include those represented by the following formulas, but are not limited thereto.

(Wherein " · " represents a bonding site with a methylene chain).

Z ¹ is a halogen atom, a group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, a sulfonic acid group, a carboxylic acid group, or an aryl group of 6 to 20 carbon atoms optionally substituted by Z ³ or a C2-nitro represents a heteroaryl group of ~20, Z ² is a halogen atom, a nitro group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, a sulfonic acid group, a carboxylic acid group, having 1 that may be substituted by Z ³ or An alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 20 carbon atoms; Z ³ represents a halogen atom, a nitro group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, , Or a carboxylic acid group.

Examples of the halogen atom, the alkyl group having 1 to 20 carbon atoms, and the aryl group having 6 to 20 carbon atoms are the same as described above.

Specific examples of the heteroaryl group having 2 to 20 carbon atoms include a 2-thienyl group, a 3-thienyl group, a 2-furanyl group, a 3-furanyl group, a 2-oxazolyl group, Isothiazolyl group, 3-isothiazolyl group, 3-isothiazolyl group, 4-isooxazolyl group, 5-isothiazolyl group, A thiazolyl group, a thiazolyl group, a 5-isothiazolyl group, a 2-imidazolyl group, a 4-imidazolyl group, a 2-pyridyl group, a 3-pyridyl group and a 4-pyridyl group.

Specific examples of the alkenylene group having 2 to 20 carbon atoms include an ethynyl group, an n-1-propenylene group, an n-2-propenylene group, a 1-methylethenyl group, methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, 1-methyl- Propenylene group, n-1-pentenylene group, n-1-deceneyl group, n-1-eicosenyl group and the like.

Specific examples of the alkynyl group having 2 to 20 carbon atoms include ethynyl, n-1-propynyl, n-2-propynyl, n-1-butynyl, N-pentyl group, n-4-pentynyl group, 1-methyl-n-butynyl group, 2-methyl n-propynyl group, n-1-hexynyl group, n-1-decynyl group, n-1-pentadecynyl group, n-1-eicosynyl group and the like.

Among them, R ¹ to R ⁸ are preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and are independently of each other preferably a hydrogen atom, a methyl group, an ethyl group or a methoxy group , All hydrogen atoms are further preferable.

As Ar ^1, a phenyl group which may be substituted with Z ² is preferable, and an unsubstituted phenyl group is more preferable.

R ⁹ and R ¹⁰ are preferably an alkyl group having 1 to 6 carbon atoms, a fluoroalkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 18 carbon atoms which may be substituted with Z ² , a cyclic group represented by the following formula in which R ⁹ and R ¹⁰ are bonded A hydrocarbon group is preferable and a cyclic hydrocarbon group represented by the following formula in which a methyl group and R ⁹ and R ¹⁰ are bonded is more preferable.

R ¹¹ and R ¹² are all preferably hydrogen atoms.

As R ¹³ to R ²⁰ , a hydrogen atom, a methyl group, an ethyl group, a trifluoromethyl group, and a halogen atom are preferable, and hydrogen atoms are more preferable.

(Wherein " · " represents a bonding site with a methylene chain).

Therefore, as X, any one of the divalent organic groups represented by the formulas (3a) to (3h) is suitable.

Among them, the divalent organic group represented by any one of formulas (3a ') to (3h') is more preferable.

The number of carbon atoms of the alkyl group, fluoroalkyl group, alkoxy group, alkenyl group and alkynyl group is preferably 10 or less, more preferably 6 or less, still more preferably 4 or less.

The number of carbon atoms of the aryl group and the heteroaryl group is preferably 14 or less, more preferably 10 or less, still more preferably 6 or less.

The molecular weight of the arylamine derivative is usually 300 to 5,000, but is preferably 4,000 or less, more preferably 3,000 or less, still more preferably 2,000 or less, from the viewpoint of improving solubility.

The arylamine derivative represented by the formula (1) of the present invention can be produced by reacting a biphenyl compound and a diamine compound in the presence of a catalyst, but the production method is not limited thereto.

For example, the arylamine derivative (6) having a bivalent organic group represented by the formula (2a) as X is obtained by reacting the biphenyl compound represented by the formula (4) with the diamine compound represented by the formula (5) . ≪ / RTI >

(Wherein Z represents a halogen atom or a similar arylene group, and R ¹ to R ¹⁰ , R ¹³ to R ²⁰ , Ar ¹ and n have the same meanings as defined above.)

The arylamine derivative (8) having a bivalent organic group represented by the formula (2b) as X is obtained by reacting the biphenyl compound represented by the formula (4) and the diamine compound represented by the formula (7) Can be obtained.

(Wherein Z represents a halogen atom or a similar halogen group, and R ¹ to R ⁸ , R ¹¹ to R ²⁰ , Ar ¹ , m and n have the same meanings as defined above.)

Examples of the halogen atom include the same ones as described above.

Examples of the similar benzene group include a (fluoro) alkylsulfonyloxy group such as methanesulfonyloxy group, trifluoromethanesulfonyloxy group and nonafluorobutainesulfonyloxy group; And aromatic sulfonyloxy groups such as benzenesulfonyloxy group and toluenesulfonyloxy group.

The charging ratio of the diamine compound represented by the formula (5) and the biphenyl compound represented by the formula (4) can be equal to or more than the equivalent amount of the biphenyl compound to the total NH group content of the diamine compound, About 1 to 1.2 equivalents are suitable.

Examples of the catalyst used in the reaction include copper catalysts such as copper chloride, copper bromide and copper iodide; Pd (PPh _{3) 4} (tetrakis (triphenylphosphine) _{palladium), Pd (PPh 3) 2} Cl 2 ( bis (triphenylphosphine) dichloropalladium), Pd (dba) ₂ (bis (dibenzylidene acetone Palladium catalysts such as palladium (Pd), Pd ₂ (dba) ₃ (tris (benzylideneacetone) dipalladium), Pd (Pt- Bu ₃ ) ₂ . These catalysts may be used alone or in combination of two or more. These catalysts may also be used together with any known ligands.

The amount of the catalyst to be used can be about 0.001 to 0.5 mol, preferably about 0.01 to 0.1 mol, in the case of using 1 mol of the diamine compound to be used.

When a ligand is used, its amount to be used may be 0.1 to 5 equivalents based on the metal complex used, but 1 to 2 equivalents are suitable.

The reaction may be carried out in a solvent. When a solvent is used, the kind thereof is not particularly limited as long as it does not adversely affect the reaction. Specific examples thereof include aliphatic hydrocarbons (pentane, n-hexane, n-octane, n-decane, decalin and the like), halogenated aliphatic hydrocarbon (such as chloroform, dichloromethane, dichloroethane, Etc.), aromatic hydrocarbons (benzene, nitrobenzene, toluene, o-xylene, m-xylene, p-xylene and mesitylene), halogenated aromatic hydrocarbons (chlorobenzene, bromobenzene dichlorobenzene, p-dichlorobenzene), ether (diethylether, diisopropylether, t-butylmethylether, tetrahydrofuran, dioxane, 1 Dimethoxyethane, 1,2-diethoxyethane and the like), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone and cyclohexanone), amides (N, Dimethylformamide, N, N-dimethylacetamide, etc.), lactams and lactones (N-methylpyrrolidone,? -Butyrolactone, etc.) (N, N-dimethylimidazolidinone, tetramethylurea and the like), sulfoxides (dimethylsulfoxide, sulfolane, etc.), nitriles (such as acetonitrile, propionitrile, ). These solvents may be used alone or in combination of two or more.

The reaction temperature may be appropriately set in the range from the melting point to the boiling point of the solvent to be used, particularly preferably from 0 to 200 캜, more preferably from 20 to 150 캜.

After completion of the reaction, the desired arylamine derivative can be obtained by post-treatment according to the conventional method.

The biphenyl compound represented by the formula (4) can be produced by reacting a biphenyl compound represented by Ar ¹ NH ₂ (wherein Ar ¹ has the same meaning as described above), a 4,4'-dihalogenated or di- Under the same catalyst.

Specific examples of the arylamine derivative represented by the formula (1) include those represented by the following formulas, but are not limited thereto. In the formulas, Y ¹ and Y ² each represent a monovalent organic group shown below.

The charge-transporting varnish of the present invention contains a charge-transporting material comprising an arylamine derivative represented by the formula (1) and an organic solvent. Depending on the purpose of the resulting thin film, the charge- Or may contain a substance.

The dopant material is not particularly limited as long as it is soluble in at least one solvent used for the varnish, and both an inorganic dopant material and an organic dopant material can be used.

Examples of the inorganic dopant substance include inorganic acids such as hydrogen chloride, sulfuric acid, nitric acid, and phosphoric acid; Aluminum chloride (III) (AlCl ₃ ), titanium tetrachloride (TiCl ₄ ), boron tribromide (BBr ₃ ), boron trifluoride ether complex (BF ₃ OEt ₂ ) ₃ ), copper (II) chloride (CuCl ₂ ), antimony antimony (V) (SbCl ₅ ), antimony pentoxide (V) (SbF ₅ ), arsenic pentafluoride (AsF ₅ ) Metal halides such as phosphorus (PF ₅ ) and tris (4-bromophenyl) aluminum hexachloroantimonate (TBPAH); Cl ₂ , Br ₂ , I ₂ , ICI, ICI ₃ , IBr, IF ₄ ; And heteropoly acids such as iminolibdic acid and phosphoric acid tungstic acid.

Organic dopants include benzenesulfonic acid, tosylic acid, p-styrenesulfonic acid, 2-naphthalenesulfonic acid, 4-hydroxybenzenesulfonic acid, 5-sulfosalicylic acid, p-dodecylbenzenesulfonic acid, Naphthalene sulfonic acid, dodecyl naphthalene sulfonic acid, 6,7-dibutyl-2-naphthalene sulfonic acid, dodecyl naphthalene sulfonic acid, 3-dodecyl-2-naphthalene sulfonic acid, hexyl naphthalene Hexyl-1-naphthalenesulfonic acid, 6-hexyl-2-naphthalenesulfonic acid, 2-octyl-1-naphthalenesulfonic acid, hexylnaphthalenesulfonic acid, Sulfonic acid, dynonylnaphthalenesulfonic acid, 2,7-dynonyl-4-naphthalenesulfonic acid, dynonylnaphthalenedisulfonic acid, 2,7-dynonyl-4,5-naphthalenedisulfonic acid, The 1,4-benzodioxane disulfonic acid compound described in the specification of International Publication No. 2006-025342, the arylsulfonic acid compound described in WO 2006/025342, International Publication No. 2009/096352 Aryl sulfone compounds such as aryl-sulfonic acid compounds, polystyrene sulfonic acid; Non-aryl sulfone compounds such as 10-camphorsulfonic acid; Organic oxidizing agents such as 7,7,8,8-tetracyanoquinodimethane (TCNQ) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) have.

These inorganic and organic dopant materials may be used singly or in combination of two or more.

Among these dopant materials, heteropolyacids are suitable, and heteropoly acids are used as the dopant materials. In addition to the fixation hole capacity represented by indium tin oxide (ITO) and indium zinc oxide (IZO) from transparent electrodes, It is possible to obtain a thin film having excellent charge transportability and exhibiting fixability to the metal anode.

The heteropolyacid typically has a Keggin type represented by the formula (B1) or a Dawson type chemical structure represented by the formula (B2), wherein the heteroatom is located at the center of the molecule and the vanadium (V), molybdenum (Mo), and tungsten (W), and an oxygen acid of a different element. Oxygen acids such as silicon (Si), phosphorus (P), and arsenic (As) can be cited as such oxygenates of these different kinds of elements.

Specific examples of the heteropoly acid include iminolibdodic acid, silicolibdodic acid, tungstic acid, tungstic acid, and tinstomolybdoduric acid, and these may be used singly or in combination of two or more kinds . The heteropoly acid used in the present invention is available as a commercial product, and may be synthesized by a known method.

In particular, when the dopant material is composed of one kind of heteropoly acid alone, the one kind of heteropoly acid is preferably tungstic acid or phospholipidic acid, and tungstic acid is the most preferable. When the dopant material is composed of two or more kinds of heteropoly acids, one of the two or more kinds of heteropoly acids is preferably tungstic acid or phospholipidic acid, and tungstic acid is more preferable.

In the quantitative analysis such as elemental analysis, the heteropoly acid may be either a product having a large number of elements or a small number of elements from the structure represented by a general formula, a product obtained as a commercial product thereof, It can be used in the present invention.

That is, for example, generally is a tungsten acid formula _{H 3 (PW 12 O 40)} · a nH ₂ O, mold ribs deneom acid, but each of the formula _{H 3 (PMo 12 O 40)} · nH 2 O, quantitative In the analysis, even if the number of P (phosphorus), O (oxygen) or W (tungsten) or Mo (molybdenum) in the formula is large or small, it may be a commercially available product, Can be used in the present invention as long as they are synthesized appropriately according to the method. In this case, the mass of the heteropoly acid specified in the present invention is not a mass of the pure tungstic acid (synthetic tungstic acid content) in a composite or a commercial product, but is in a form obtainable on the market and in a form that can be isolated by a known synthetic method, And other impurities and the like.

An arylsulfonic acid compound may also be suitably used as a dopant material. In particular, the arylsulfonic acid compound represented by the formula (7) or (8) is preferable.

A ¹ represents O or S, with O being preferred.

A ² represents a naphthalene ring or an anthracene ring, but a naphthalene ring is preferable.

A ³ represents a perfluorobiphenyl group having 2 to 4 valences, p denotes an integer number of bonds between A ¹ and A ³ and is an integer satisfying 2? P? ⁴ , wherein A ³ is a divalent perfluorobiphenyl group , And p is preferably 2.

q represents a sulfonic acid group bonded to A ² and is an integer satisfying ^1? q? ⁴ , but 2 is optimal.

A ^{4 to} A ⁸ independently represent a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, or a halogenated alkenyl group having 2 to 20 carbon atoms , But at least three of A ^{4 to} A ⁸ are halogen atoms.

Examples of the halogenated alkyl group having 1 to 20 carbon atoms include a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2,2-pentafluoroethyl group, a 3,3,3-trifluoro- Propyl group, 2,2,3,3,3-pentafluoropropyl group, 1,1,2,2,3,3,3-heptafluoropropyl group, 4,4,4-trifluorobutyl group , 3,3,4,4,4-pentafluorobutyl group, 2,2,3,3,4,4,4-heptafluorobutyl group, 1,1,2,2,3,3,4 , 4,4-nonafluorobutyl group, and the like.

Examples of the halogenated alkenylene group having 2 to 20 carbon atoms include a perfluorovinyl group, a perfluoropropenyl group (allyl group), and a perfluorobutenyl group.

In addition, examples of the halogen atom and the alkyl group having 1 to 20 carbon atoms are the same as those described above, but a halogen atom is preferably a fluorine atom.

Of these, A ^{4 to} A ⁸ are a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 10 carbon atoms, or a halogenated alkenylene group having 2 to 10 carbon atoms, At least three of A ^{4 to} A ⁸ are preferably a fluorine atom and are preferably a hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 5 carbon atoms, an alkyl fluoride group having 1 to 5 carbon atoms, More preferably a fluorine atom, a fluorine atom, a cyano group, a perfluoroalkyl group having 1 to 5 carbon atoms, or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably at least three of A ^{4 to} A ⁸ are fluorine atoms, Perfluoroalkylene group, and further preferably A ⁴ , A ⁵ and A ⁸ are fluorine atoms.

The perfluoroalkyl group is a group in which all the hydrogen atoms of the alkyl group are substituted with fluorine atoms, and the perfluoroalkylene group is a group in which all the hydrogen atoms of the alkenyl group are substituted with fluorine atoms.

r is an integer satisfying 1? r? 4, preferably 2 to 4, and most preferably 2, the number of sulfonic acid groups bonded to the naphthalene ring.

The molecular weight of the arylsulfonic acid compound used as the dopant material is not particularly limited, but is preferably 2,000 or less, and more preferably 1,500 or less, in consideration of the solubility in an organic solvent when used together with the charge-transporting substance.

Specific examples of the arylsulfonic acid compound suitable as the dopant material in the present invention include, but are not limited to, the following.

When the dopant material is included in the charge transporting varnish of the present invention, the amount of the dopant material to be used is appropriately determined in consideration of the kind of the dopant material, the degree of desired charge transportability, and the like. Of the charge transport material 1 in terms of the mass ratio, but it is preferably in the range of 0.1 to 20, more preferably 0.2 to 10, from the viewpoint of improving the charge transportability of the resulting thin film.

As the organic solvent used for preparing the charge transporting varnish, a solvent capable of dissolving a charge-transporting material and a dopant material to be used as needed can be used.

Examples of such a solubilizing solvent include cyclohexanone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl- Diethylene glycol monomethyl ether, and the like, but are not limited thereto. These solvents may be used singly or in combination of two or more, and the amount thereof may be 5 to 100% by mass based on the total solvent used in the varnish.

Further, both the charge-transporting substance and the dopant substance are preferably completely dissolved or uniformly dispersed in the solvent, and more preferably completely dissolved.

In the present invention, the varnish preferably contains at least a highly viscous organic solvent having a viscosity of 10 to 200 mPa · s, particularly 35 to 150 mPa · s at 25 ° C. and a boiling point of 50 to 300 ° C., particularly 150 to 250 ° C., The inclusion of one kind makes it easy to adjust the viscosity of the varnish. As a result, it is possible to prepare a varnish suitable for a coating method in which thin films with high flatness are supplied with good reproducibility.

Examples of the highly viscous organic solvent include organic solvents such as cyclohexanol, ethylene glycol, ethylene glycol diglycidyl ether, 1,3-octyleneglycol, diethylene glycol, dipropylene glycol, Triethylene glycol, tripropylene glycol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, propylene glycol, hexylene glycol and the like But the present invention is not limited thereto. These solvents may be used alone or in combination of two or more.

The addition ratio of the highly viscous organic solvent to the entire solvent used in the varnish of the present invention is preferably within a range where no solid is precipitated, and the addition ratio is preferably 5 to 90% by mass so long as no solid is precipitated.

Further, for the purpose of improving the wettability of the substrate, adjusting the surface tension of the solvent, adjusting the polarity, and adjusting the boiling point, other solvents may be used in an amount of 1 to 90% by mass, And may be mixed at a ratio of 1 to 50 mass%.

Examples of such a solvent include propylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol Diethylene glycol monomethyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, diacetone Alcohols,? -Butyrolactone, ethyl lactate, n-hexyl acetate, and the like, but are not limited thereto. These solvents may be used singly or in combination of two or more.

The viscosity of the varnish of the present invention is suitably set in accordance with the thickness of the thin film to be produced or the solid content concentration, but is usually 1 to 50 mPa · s at 25 ° C.

The solid concentration of the charge transporting varnish in the present invention is appropriately set in consideration of the viscosity and the surface tension of the varnish, the thickness of the thin film to be produced, and the like, but is usually about 0.1 to 10.0 mass% It is preferably about 0.5 to 5.0 mass%, and more preferably about 1.0 to 3.0 mass%.

The charge-transporting thin film can be formed on the substrate by applying the charge-transporting varnish described above to the substrate and firing it.

The application method of the varnish is not particularly limited, and examples thereof include a dipping method, a spin coating method, a transfer printing method, a roll coating method, a brush coating method, an ink jet method, a spraying method and a slit coating method. It is preferable to adjust the viscosity and the surface tension of the polymer.

The firing atmosphere is not particularly limited, but an atmosphere is preferable.

The firing temperature is suitably set in the range of about 100 to 260 DEG C in consideration of the use of the thin film to be obtained, the degree of charge transportability given to the resulting thin film, the type and boiling point of the solvent, When used as an injection layer, it is preferably about 140 to 250 캜, and more preferably about 145 to 240 캜.

Further, at the time of firing, a temperature change of two or more stages may be given for the purpose of developing a higher uniform film-forming property or promoting the reaction on a substrate. Heating may be carried out by, for example, You can do this using a device.

Though the thickness of the charge transporting thin film is not particularly limited, it is preferably 5 to 200 nm when used as the hole injecting layer in the organic EL device. As a method of changing the film thickness, there is a method of changing the solid content concentration in the varnish or changing the amount of the solution on the substrate at the time of coating.

Materials and methods for producing an organic EL device using the charge transporting varnish of the present invention include, but are not limited to, the following materials.

It is preferable that the electrode substrate to be used is cleaned by previously performing liquid cleaning with detergent, alcohol, pure water or the like. For example, in the case of the positive electrode substrate, it is preferable to perform surface treatment such as UV ozone treatment and oxygen- Do. However, in the case where the anode material is composed mainly of an organic material, the surface treatment need not be performed.

An example of a method for producing an organic EL device having a hole injection layer made of a thin film obtained from the charge transporting varnish of the present invention is as follows.

By the above method, the charge transporting varnish of the present invention is coated on the anode substrate and fired to prepare a hole transporting layer on the electrode. This is introduced into a vacuum deposition apparatus, and a hole transporting layer, a light emitting layer, an electron transporting layer, an electron injecting layer / hole blocking layer, and a cathode metal are sequentially deposited to obtain an organic EL device. If necessary, an electron blocking layer may be provided between the light emitting layer and the hole transporting layer.

As the cathode material, a transparent anode typified by indium tin oxide (ITO) or indium zinc oxide (IZO), a metal anode typified by aluminum, or a metal anode composed of an alloy thereof may be used. . A polythiophene derivative or a polyaniline derivative having high charge transportability may be used.

Examples of other metals constituting the metal anode include scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, yttrium, zirconium, niobium, molybdenum, ruthenium, Cadmium, indium, scandium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, hafnium, thallium, tungsten, rhenium, osmium, Gold, titanium, lead, bismuth, and alloys thereof, but are not limited thereto.

(Triphenylamine) dimer derivative, [(triphenylamine) dimer] spiro dimer, and N, N'-bis (naphthalen-1-yl) -N, N'- -N, N'-bis (3-methylphenyl) -N, N'-bis (phenylnaphthyl) -Bis (phenyl) -benzidine, N, N'-bis (3-methylphenyl) -N, N'- -9,9-bis (phenyl) -9,9-spirobifluorene, N, N'-bis (3-methylphenyl) -N, N'- N, N'-bis (3-methylphenyl) -9,9-dimethyl-fluorene, N, N'-bis (naphthalen- (Phenyl) -9,9-diphenyl-fluorene, N, N'-bis (naphthalen-1-yl) -N, N'- N, N'-bis (phenyl) -2,2'-dimethylbenzidine, 2,2 ', 7,7'-tetra Kiss (N, N-diphenylamino) -9,9-spirobifluor Phenylen-9H-fluorene, 9,9-bis [4- (N, N-bis-naphthalene- Phenyl] -9H-fluorene, 2,2 ', 4'-bis [4- (N-naphthalen- N, N'-bis (phenanthrene-9-yl) -N, N'-tetrakis [N-naphthalenyl Bis (phenyl) -benzidine, 2,2'-bis [N, N-bis (biphenyl-4-yl) amino] -9,9- spirobifluorene, 2,2'-bis - diphenylamino) -9,9-spirobifluorene, di- [4- (N, N-di (p- tolyl) amino) -phenyl] cyclohexane, 2,2 ' N, N ', N'-tetra-naphthalen-2-yl-benzidine, and N, N'- N, N'-di (naphthalen-2-yl) -benzidine, N, N'-tetra- (3-methylphenyl) -3,3'-dimethylbenzidine, N, N ', N'-tetra (naphthalenyl) -benzidine, N, '- diphenyl-benzidine-1,4-diamine, N ^1, N ^4-diphenyl-1 -N, N ⁴ -di (m- tolyl) benzene-1,4-diamine, N ^2, N ^2, N ^6, N ⁶ - tetraphenyl naphthalene-2,6-diamine, tris (4- (quinolin-8-yl) phenyl) amine, 2,2'-bis (3- (N, N- di (p- tolyl ) Amino) phenyl) biphenyl, 4,4 ', 4 "-tris [3-methylphenyl (phenyl) amino] triphenylamine (4-methylphenyl) amino] phenyl} -2,2 ': 5' -tri (phenyl) amino] triphenylamine (1-TNATA) , 2 " -terthiophene (BMA-3T), and the like.

As the material for forming the light emitting layer, tris (8-quinolinolate) aluminum (III) (Alq ₃ ), bis (8-quinolinolate) zinc (II) (Znq ₂ ) Quinolinolate) -4- (p-phenylphenolate) aluminum (III) (BAlq), 4,4'-bis (2,2-diphenylvinyl) biphenyl, 9,10- Di (naphthalen-2-yl) anthracene, 2,7-bis [9,9-di (4-methylphenyl) (Naphthalene-2-yl) anthracene, 2- (9,9-spirobifluoren-2-yl) -9 , 9- spirobifluorene, 2,7-bis (9,9-spirobifluorene-2-yl) -9,9-spirobifluorene, 2- [9,9- -Methylphenyl) -fluorene-2-yl] -9,9-di (4-methylphenyl) fluorene, 2,2'- (9,10-diphenylanthracene), 2, 2, 3, 4, 5, 6, (Pyrene-1-yl) benzene, 6,13-di (pyrene-1-yl) benzene, (Biphenyl-4-yl) pentacene, 3,9-di (naphthalen-2-yl) perylene, 3,10- Phenyl] amine, 10,10'-di (biphenyl-4-yl) -9,9'-bianthracene, N, N'- 1,1 ': 4', 1 ": 4", 1 "" -quaterphenyl] -4,4''-diamine, 4,4'-di [10- (naphthalen- ) Anthracene-9-yl] biphenyl, dibenzo {[f, f '] -4,4', 7,7'- , 3'-lm] perylene, 1- (7- (9,9'-bianthracene-10-yl) -9,9- (Carbazole-9-yl) benzene, 1,1-bis (9,9'-bithanthracene-10-yl) -9,9-dihexyl-9H- (Carbazol-9-yl) benzene, 4,4 ', 4 "-tris (carbazol-9-yl) triphenylamine, 4,4'- ) Biphenyl, 4,4'-bis (carbazol-9-yl) -2,2'-di (Carbazol-9-yl) -9,9-dimethylfluorene, 2,2 ', 7,7'-tetrakis (carbazol-9-yl) -9, 9,9-bis [4- (carbazol-9-yl) -9,9-di (p-tolyl) fluorene, 9,9- ) -Phenyl] fluorene, 2,7-bis (carbazol-9-yl) -9,9-spirobifluorene, 1,4-bis (triphenylsilyl) benzene, 1,3- (4-N, N-diethylamino-2-methylphenyl) -4-methylphenyl methane, 2,7-bis (carbazol- , 4,4'-di (triphenylsilyl) -p-terphenyl, 4,4'-di (triphenylsilyl) biphenyl, 9- Carbazole, 9- (4-t-butylphenyl) -3,6-ditolyl-9H-carbazole, 9- (9- (9H-carbazol-9-yl) phenyl) pyridine, triphenyl (triphenylphosphine) (9- phenyl-9H-fluoren-9-yl) phenyl) silane, 9,9-dimethyl-N, N Phenyl) -9H-fluorene-2-amine, 3,5-bis (3- (9H- 9-yl) phenyl) pyridine, 9,9-spirobifluorene-2-yl-diphenylphosphine oxide, 9,9 '- (5- (triphenylsilyl) (9H-carbazole), 3- (2,7-bis (diphenylphosphoryl) -9-phenyl-9H-fluorene- , 4,8,8,12,12-hexa (p-tolyl) -4H-8H-12H-12C-aza dibenzo [cd, mn] pyrene, 4,7-di (9H-carbazol- Bis (diphenylphosphoryl) dibenzo [b, d] azepin-2-yl) -1,10-phenanthroline, 2,2'- Di (9H-carbazol-9-yl) phenyl] diphenylsilane, 3,6-bis (carbazol-9-yl ) -9- (4- (diphenylphosphoryl) phenyl) -9H-carbazole, 3,6-bis [(3,5-diphenyl) phenyl] -9-phenylcarbazole, and the like, and a luminescent dopant and notarization By, or formed of a light-emitting layer.

Examples of the luminescent dopant include 3- (2-benzothiazolyl) -7- (diethylamino) quadmarine, 2,3,6,7-tetrahydro-1,1,7,7-tetramethyl- , 11H-10- (2-benzothiazolyl) quinolizino [9,9a, 1gh] quimarin, quinacridone, N, N'-dimethyl- quinacridone, tris (2-phenylpyridine) iridium (III) (Ir (ppy) _3), bis (2-phenylpyridine) (acetylacetonate) iridium (III) (Ir (ppy) ₂ (acac)), tris [2- (p- tolyl) pyridine] iridium (M-tolyl) amino] anthracene, bis [2, ₃ -di (p- tolyl) amino] anthracene, - (2-hydroxyphenyl) benzothiazolale] zinc (II), N ¹⁰ , N ¹⁰ , N ^{10 '} , N ^10' '- ^{diamine, N 10, N 10, N} 10', N 10 '- tetraphenyl -9,9'- bi anthracene -10,10'- diamine, N ^10, N ^10' - ¹⁰ -N-diphenyl , ¹⁰ N ^'- dimethyl -9,9'- bi-naphthalenyl anthracene -10,10'- diamine, 4,4'-bis (9-ethyl-3-vinyl carbazole crude alkylene) -1,1' Bis [2- (3-N-ethylcarbazolyl) vinyl] benzene, 4,4'-bis [ 4 - [(di-p-tolylamino) styryl] stilbene, bis (3,5 (2-pyridyl) phenyl- (2-carboxypyridyl) iridium (III), 4,4'-bis [4- (diphenylamino) styryl] biphenyl, bis N, N'-bis (phenyl) -bis (iridium) borate iridium (III) -Tris (9,9-dimethylfluorenylene), 2,7-bis {2- [phenyl (m-tolyl) amino] -9,9- -Dimethyl-fluorene, N- (4 - ((E) -2- (6 (E) -4- (diphenylamino) styryl) naphthalen- Iridium (III) tris (1-phenyl-3-methylbenzimidazoline-2-ylidene-C, C ^{2 '} ), mer- Benzimidazole 2-ylidene-C, C ^{2 '} ), 2,7-bis [4- (diphenylamino) styryl] -9,9- spirobifluorene, Yl) phenyl) benzo [d] thiazole, 1,4-di [4- (N, N (E) -6- (4- (diphenylamino) styryl) benzene, 1,4-bis (4- (9H-carbazol- (III), N, N-diphenyl naphthalene-2-amine, bis (2,4-difluorophenylpyridinate) (5- (pyridin- Bis (3-trifluoromethyl-5- (2-pyridyl) pyrazole) ((2,4-difluorobenzyl) diphenylphosphinate) iridium (III) (Benzyl diphenylphosphinate) iridium (III), bis (1- (2,4-difluorobenzyl) -3-methylbenzimidazolium) ( 3- (Trifluoromethyl) -5- (2-pyridyl) -1,2,4-triazololate A solution of iridium (III), bis (3-trifluoromethyl- (4 ', 6'-difluorophenyl pyridinate) (3', 6'-difluorophenyl pyridinate) iridium (III) (Trifluoromethyl) -2- (2'-pyridyl) pyrrolate), iridium (III), bis (4 ', 6'-difluorophenylpyridinate) (2-pyridyl) -1,2,4-triazolate) iridium (III), (Z) -6-mesityl-N- (6-mesitylquinolin- - ylidene) quinolin-2-amine _{-BF 2, (E) -2- (} 2- (4- ( dimethylamino) styryl) -6-methyl -4H- pyran-4-ylidene) words furnace nitro Methyl-6-methyl-6- (1, 1, 7-tetramethyl- , 7-tetramethyljulolididyl-9-enyl) -4H-pyran, 4- (dicyanomethylene) -2-t- butyl- 6- (1,1,7,7-tetramethyl- 4-yl-vinyl) -4H-pyran, tris (dibenzoylmethane) phenanthroline europium (III), 5,6,11,12-tetraphenylnaphthacene, bis Iridium (III), tris (1-phenylisoquinoline) iridium (III), bis (1-phenylisoquinoline) (acetylacetonate) iridium (III) - (9,9-dimethyl-9H-fluoren-2-yl) -isoquinoline] (acetylacetonate) iridium (III) (2,2 ') - bipyridine] ruthenium (III) bis (hexafluorophosphate), and tris [4,4'-di- Tris (2-phenylquinoline) iridium (III), bis (2-phenylquinoline) (acetylacetonate) iridium (III), 2,8- Butylphenyl) -6,12-diphenyltetracene, bis (2-phenylbenzothiazolate) (acetylacetonate) iridium (III), 5,10,15,20-tetraphenyltetrabenzoporphyrin platinum, osmium II) bis (3-trifluoromethyl-5- (2-pyridine) -pyrazolate) dimethylphenylphosphine, osmium (II) bis - (trifluoromethyl) -5- (4-t-butylpyridyl) -1,2,4-triazoleate) diphenylmethylphosphine, osmium (II) bis (3- (trifluoromethyl) (4-t-butylpyridyl) -5- (2-pyridyl) -1,2,4-triazole dimethylphenylphosphine, osmium (II) bis (3- (trifluoromethyl) (4-n-hexylphenyl) quinoline] (acetylacetonate) iridium (III), tris [2- (4-n-hexyl) Phenyl) quinoline] iridium (III), tris [2-phenyl-4-methylquinoline] iridium (III), bis (2-phenylquinoline) (Acetylacetonate) iridium (III), bis (2-phenylpyridine), bis (2-phenylpyridine) (3- (pyridin-2-yl) -2H-chromen-2-onate) iridium (III), bis (2-phenylquinoline) (2,2,6,6-tetramethylheptane- - dionate) iridium (III), bis (phenylisoquinoline) (2,2, 6,6-tetramethyl-heptane-3,5-diode carbonate) iridium (III), iridium (III) bis (4-wrapped in no [3,2-c] pyridinyl Nei Sat -N, C ^{2 '} ) Acetylacetonate, (E) -2- (2-t-butyl-6- (2- (2,6,6-trimethyl-2,4,5,6-tetrahydro-lH- pyrrolo [3 , 2,1-ij] quinolin-8-yl) vinyl) -4H-pyran-4-ylidene) malononitrile, bis (3-trifluoromethyl-5- (1-isoquinolyl) pyrazole (Methyldiphenylphosphine) ruthenium, bis [(4-n-hexylphenyl) isoquinoline] (acetylacetonate) iridium (III), platinum (II) f, h] quinoxaline (acetylacetonate) iridium (III) and tris [(4-n-hexylphenyl) isoquinoline] iridium (III).

Examples of the material for forming the electron transporting layer / hole blocking layer include 8-hydroxyquinolinolate-lithium, 2,2 ', 2 "- (1,3,5-benzyltolyl) Benzimidazole), 2- (4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,9- 1, 10-phenanthroline, 4,7-diphenyl-1,10-phenanthroline, bis (2-methyl-8- quinolinolato) -4- (phenylphenolate) - bis [2- (2,2'-bipyridin-6-yl) -1,3,4-oxadiazo-5-yl] benzene, 6,6'- Yl) -2,2'-bipyridine, 3- (4-biphenyl) -4-phenyl-5-t-butylphenyl- (Naphthalene-2-yl) -4,7-diazabicyclo < / RTI > -Diphenyl-1,10-phenanthroline, 2,7-bis [2- (2,2'-bipyridin-6-yl) -1,3,4-oxadiazo- 1,3-bis [2- (4-t-butylphenyl) -1,3,4-oxadiazo-5-yl] benzene, tris (2,4,6-tri Methyl-2- (4- (naphthalen-2-yl) phenyl) -1H-imidazo [4,5f] [1,10] phenan- Tributylphosphine oxide, 3,3 ', 5,5'-tetra [((naphthalen-2-yl) -4,7-diphenyl-1,10-phenanthroline, (3-pyridyl) -phen-3-yl] benzene, 4,4'-bis (4,6-di Bis (3,5-di (pyridin-3-yl) phenyl] benzene, bis (10-hydroxybenzo [h] (Pyrin-3-yl) phenyl) silane, and 3,5-di (pyrene-1-yl) pyridine.

Oxide as the material forming the electron injection layer of lithium (Li ₂ O), magnesium oxide (MgO), alumina (Al ₂ O _3), lithium fluoride (LiF), fluoride sodium (NaF), magnesium fluoride (MgF _2), fluoride Cesium fluoride (CsF), strontium fluoride (SrF ₂ ), molybdenum trioxide (MoO ₃ ), aluminum, lithium acetylacetonate (Li (acac)), lithium acetate and lithium benzoate.

Examples of the anode material include aluminum, a magnesium-silver alloy, an aluminum-lithium alloy, lithium, sodium, potassium, cesium and the like.

As a material for forming the electronic block layer, tris (phenylpyrazole) iridium and the like can be mentioned.

The method for producing the PLED device using the charge transporting varnish of the present invention is not particularly limited, but the following methods can be used.

In the production of the organic EL device, the hole transporting polymer layer and the luminescent polymer layer are sequentially formed instead of the vacuum evaporation operation of the hole transporting layer, the light emitting layer, the electron transporting layer, and the electron injecting layer to form the charge transporting varnish of the present invention A PLED device having a transport thin film can be manufactured.

Specifically, the hole transporting varnish of the present invention is applied onto the anode substrate, the hole injecting layer is formed by the above method, the hole transporting polymer layer and the luminescent polymer layer are sequentially formed thereon, and the cathode is vapor- .

As the cathode and cathode materials to be used, the same materials as those used for manufacturing the organic EL device can be used, and the same cleaning treatment and surface treatment can be performed.

The hole-transporting polymer layer and the light-emitting polymer layer may be formed by dissolving or uniformly dispersing a solvent in a hole transporting polymer material or a luminescent polymer material or a material to which a dopant material is added, Followed by firing each of them.

As the hole transporting polymeric material, poly [(9,9-diahexylfluorenyl-2,7-diyl) -co- (N, N'-bis {p- ), Poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (N, N'-bis {p-butylphenyl} -1,1'- Diamine)], poly [(9,9-bis {1'-pentene-5'-yl} fluorenyl-2,7-diyl) -co- (N, N'- (Phenylphenyl) -1,4-diaminophenylene), poly [N, N'-bis (4-butylphenyl) -N, N'-bis (4,4 '- (N- (p-butylphenyl)) diphenylamine)] and the like, .

Examples of the luminescent polymer material include polyfluorene derivatives such as poly (9,9-dialkylfluorene) (PDAF), poly (2-methoxy-5- (2'-ethylhexoxy) (MEH-PPV), polythiophene derivatives such as poly (3-alkylthiophene) (PAT), and polyvinyl carbazole (PVCz).

Examples of the solvent include toluene, xylene, and chloroform. Examples of the dissolution or uniform dispersion method include stirring, heating stirring, and ultrasonic dispersion.

The application method is not particularly limited, and examples thereof include an ink jet method, a spray method, a dipping method, a spin coating method, a transfer printing method, a roll coating method, and a brush coating method. The application is preferably carried out under an inert gas such as nitrogen or argon.

As a method of baking, a method of heating in an oven or a hot plate under an inert gas or in a vacuum may be mentioned.

Example

Hereinafter, the present invention will be described in more detail by way of Synthesis Examples and Examples, but the present invention is not limited to the following Examples. The apparatus used is as follows.

(1) ¹ H-NMR: ECX-300 manufactured by Nihon Denshi Co., Ltd.

(2) LC / MS: ZQ2000 manufactured by Waters Co.

(3) Substrate cleaning: Substrate cleaning apparatus (reduced pressure plasma system) manufactured by Chosushi Sangyo Co.,

(4) Application of Varnish: Spin Coater MS-A100 manufactured by Mikasa Co., Ltd.

(5) Measurement of film thickness: Kosaka Kyokusho Co., Ltd. Fine shape measuring instrument Surfcoder ET-4000

(6) Fabrication of EL device: Multifunctional deposition apparatus system C-E2L1G1-N manufactured by Chosho Sangyo Co., Ltd.

(7) Measurement of luminance and the like of the EL element: (I) Tech World I-V-L measurement system

[1] Synthesis of arylamine derivative

[Synthesis Example 1] Synthesis of Compound 1

4-bromo-4'-in child ohdobayi phenyl (8.98g, 25mmol, Tokyo Kasei Kogyo (Co., Ltd.)), aniline toluene suspension (90mL) of (2.56g, 27.5mmol), Pd ( PPh 3) 4 (1.44 g, 1.25 mmol) and t-BuONa (2.88 g, 30 mmol) were added, and the mixture was heated under reflux for 10 hours. After completion of the reaction, the reaction mixture was allowed to cool to room temperature and filtered through celite. The filtrate was concentrated and the resulting crude product was purified by silica gel column chromatography (eluent: toluene) to concentrate the fraction containing the compound 1 (fraction). To the resulting crude product was added a mixed solvent of ethanol / toluene (3: 1 (w / w)) and dissolved under heating and refluxing. After cooling to room temperature, the precipitated solid was filtered to obtain Compound 1 (6.96 g, yield 86%) as a pale brown solid. The measurement results of ¹ H-NMR and LC / MS are shown below.

[Synthesis Example 2] Synthesis of arylamine derivative H1

To a xylene suspension (10 mL) of 9,9-bis (4-aminophenyl) fluorene (1 g, 2.87 mmol, manufactured by Tokyo Kasei Kogyo K.K.) and Compound 1 (1.95 g, 6.0 mmol) obtained in Synthesis Example 1 _{, Pd (PPh 3) 4 (} 166mg, 0.14mmol), t-BuONa was added (0.66g, 6.89mmol), was heated to reflux and then purged with nitrogen for 4 hours. After that, the compound 1 (0.37 g, 1.1 mmol) obtained in Synthesis Example 1 and t-BuONa (0.11 g, 1.21 mmol) were added and the mixture was heated to reflux for 6 hours. After completion of the reaction, the mixture was allowed to cool to room temperature, chloroform (40 mL) and water (40 mL) were added, and the mixture was stirred at room temperature for 30 minutes. The insoluble solid was collected by filtration, dissolved in THF and filtered through celite. The filtrate was concentrated, and the resulting crude product was purified by silica gel column chromatography (eluent: hexane / ethyl acetate (1/1 (v / v))) to concentrate the oil containing the arylamine derivative H1. The obtained crude product was washed with ethanol to obtain an arylamine derivative H1 (1.15 g, yield 48%) as a pale gray solid. The measurement results of ¹ H-NMR and LC / MS are shown below.

[Synthesis Example 3] Synthesis of arylamine derivative H2

1,1-bis (4-aminophenyl) cyclohexane (0.8g, 3mmol, Tokyo Kasei Kogyo (Co., Ltd.)) of the compound obtained in Synthesis Example 1 1 (2.14g, 6.6mmol), Pd (PPh 3) 4 (1.26 g, yield 56%) was obtained in the same procedure as in Synthesis Example 2, except that t-BuONa (0.72 g, 7.5 mmol) and xylene (8 mL) ). The measurement results of ¹ H-NMR and LC / MS are shown below.

[Synthesis Example 4] Synthesis of arylamine derivative H3

4,4'-diamino diphenyl methane (0.6g, 3mmol, Tokyo Kasei Kogyo (Co., Ltd.)), the compound obtained in Synthesis Example 1 1 (2.14g, 6.6mmol), Pd (PPh 3) 4 (173mg, 0.15 mmol), t-BuONa (0.72 g, 7.5 mmol) and xylene (6 mL) were used in the same manner as in Synthesis Example 2 to obtain an arylamine derivative H3 (1.45 g, yield 71%) as a pale gray solid. The measurement results of ¹ H-NMR and LC / MS are shown below.

[2] preparation of charge transport varnish

[Example 1-1]

A mixture of 0.113 g (0.135 mmol) of the arylamine derivative H1 and 0.091 g (0.101 mmol) of the dopant substance D1 represented by the following formula was added to a mixture of 1,3-dimethyl-2-imidazolidinone 7.2 g. To this solution, 1.4 g of cyclohexanol and 1.4 g of propylene glycol were added and sufficiently stirred to obtain a yellow transparent solution. The resulting solution was filtered using a PTFE filter having a pore diameter of 0.2 占 퐉 to obtain a yellow transparent charge-transporting varnish (solid content concentration: 2.0% by mass).

Further, the dopant substance D1 was synthesized based on the description in WO 2006/025342.

[Example 1-2]

A yellow transparent charge-transporting varnish was obtained in the same manner as in Example 1-1 except that a mixture of 0.098 g (0.117 mmol) of the arylamine derivative H1 and 0.106 g (0.117 mmol) of the dopant D1 was used (solid content concentration 2.0 mass% %).

[Example 1-3]

A yellow transparent charge-transporting varnish was obtained in the same manner as in Example 1-1 except that a mixture of 0.062 g (0.074 mmol) of the arylamine derivative H1 and 0.247 g of tungstic acid (manufactured by Kanto Kagaku Co., Ltd.) was used Solid content concentration: 3.0% by mass).

[Example 1-4]

(Solid content concentration: 3.0% by mass) was obtained in the same manner as in Example 1-1 except that a mixture of 0.062 g (0.082 mmol) of the arylamine derivative H2 and 0.247 g of tungstic acid was used.

[Example 1-5]

(Solid content concentration: 3.0% by mass) was obtained in the same manner as in Example 1-1 except that a mixture of 0.062 g (0.090 mmol) of the arylamine derivative H3 and 0.247 g of tungstic acid was used.

[3] Fabrication and initial characteristics of organic EL devices

A glass substrate (hereinafter abbreviated as ITO substrate) of 25 mm x 25 mm x 0.7 t in which indium tin oxide was patterned to have a film thickness of 150 nm on the surface was used as a substrate for evaluating the electrical characteristics. The ITO substrate was used after removing impurities on the surface by using an O ₂ plasma cleaning apparatus (150 W, 30 seconds).

[Example 2-1]

The varnish obtained in Example 1-1 was applied to an ITO substrate using a spin coater, dried at 80 DEG C for 1 minute, and further baked at 230 DEG C for 15 minutes to form a uniform thin film of 30 nm on the ITO substrate.

With respect to the ITO substrate to form a thin film, using the evaporation apparatus α-NPD, Alq _3, lithium fluoride, and a laminated aluminum film in order to obtain an organic EL device. The deposition was carried out under conditions of a film thickness of 30 nm, 40 nm, 0.5 nm and 100 nm, a degree of vacuum of 1.0 × 10 ^-5 Pa, a deposition rate of 0.02 nm / sec for lithium fluoride and 0.2 nm / sec for the other materials.

Further, in order to prevent deterioration of characteristics due to the influence of oxygen, water, and the like in the air, the organic EL element was sealed with a sealing substrate, and then its characteristics were evaluated. The sealing was performed in the following procedure.

The organic EL device was placed in a sealing substrate in a nitrogen atmosphere having an oxygen concentration of 5 ppm or less and a dew point of -80 占 폚 or less and the sealing substrate was bonded with an adhesive. At this time, as the desiccant HD-071010W-40 made by Dainic Co., Ltd. was put together with the organic EL element in the sealing substrate. As the adhesive agent, MORESCO Moisture Moisture Cut WB90US (P) manufactured by MORESCO Co., Ltd. was used. The bonded sealing substrate was irradiated with UV light (wavelength: 365 nm, irradiation amount: 6000 mJ / cm ² ) and annealed at 80 캜 for 1 hour to cure the adhesive.

[Examples 2-2 to 2-5]

An organic EL device was fabricated in the same manner as in Example 2-1 except that the varnish obtained in Examples 1-2 to 1-5 was used.

The electric characteristics of the organic EL devices obtained in Examples 2-1 to 2-5 were measured using a current-voltage-luminance measurement system. Table 1 shows the current density and luminance at a driving voltage of 5V. The area of the light emitting surface size of each element is 2 mm x 2 mm.

Current density
(mA / cm ² ) Luminance
(cd / m ² ) Example 2-1 55 1700 Example 2-2 58 1691 Example 2-3 100 2428 Examples 2-4 101 2580 Example 2-5 103 2605

As shown in Table 1, it can be seen that the organic EL devices manufactured in Examples 2-1 to 2-5 emit light sufficiently within a practical voltage range.

From the above, it has been found that an organic EL device having excellent luminance characteristics can be obtained by using a thin film using the charge-transporting material of the present invention as a hole injection layer.

Claims (9)

A charge-transporting material comprising an arylamine derivative represented by the formula (1).

Wherein R ¹ to R ⁸ independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, which may be substituted with Z ¹ ,
Ar ¹ represents an aryl group having 6 to 20 carbon atoms which may be substituted with Z ² ,
n represents an integer of 1 to 3,
X represents a divalent organic group represented by the formula (2a) or (2b)

(Wherein R ⁹ and R ¹⁰ are independently of each other an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms which may be substituted with Z ² , or R ⁹ And R < ¹⁰ > are bonded to form a cyclic hydrocarbon group of 3 to 21 carbon atoms which may be condensed,
R ¹¹ and R ¹² independently represent a hydrogen atom or a fluorine atom,
R ¹³ to R ²⁰ independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, or Z ³ ,
and m represents an integer of 1 to 4).
Z ¹ is a halogen atom, a group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, a sulfonic acid group, a carboxylic acid group, or an aryl group of 6 to 20 carbon atoms optionally substituted by Z ³ or a C2-nitro Lt; / RTI > to < RTI ID =
Z ² is a halogen atom, a nitro group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, a sulfonic acid group, a carboxylic acid group, or an alkyl group, having 1 to 20 carbon atoms optionally substituted by Z ^3, carbon number of 2 to An alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 20 carbon atoms,
Z ³ represents a halogen atom, a nitro group, a cyano group, an amino group, an aldehyde group, a hydroxyl group, a thiol group, a sulfonic acid group or a carboxylic acid group. The method according to claim 1,
Wherein X is one kind selected from divalent organic groups represented by formulas (3a) to (3h).

A charge-transporting material comprising the charge-transporting material according to claim 1 or 2. A charge-transporting varnish comprising the charge-transporting material according to claim 1 or 2 and an organic solvent. 5. The method of claim 4,
Lt; RTI ID = 0.0 > a < / RTI > dopant material. 6. The method of claim 5,
Wherein the dopant material comprises a heteropoly acid. A charge transport thin film produced using the charge transporting varnish according to any one of claims 4 to 6. An organic electroluminescence device having the charge transporting thin film according to claim 7. A process for producing a charge-transporting thin film characterized by coating the charge-transporting varnish according to any one of claims 4 to 6 on a substrate and evaporating the solvent.