KR20160021181A - Thiophene derivative, use thereof, and production method of thiophene derivative - Google Patents

Abstract

(R¹∼R⁴는 알킬, 알켄일, 알킨일, 알콕시, 알켄일옥시, 알킨일옥시, 알킬싸이오, 알킨일싸이오, 아릴옥시, 헤테로아릴옥시, 아릴싸이오 또는 헤테로아릴싸이오를, R⁵∼R⁸은 수소, 알킬, 알켄일, 알킨일, 알콕시, 알켄일옥시, 알킨일옥시, 알킬싸이오, 알킨일싸이오, 아릴옥시, 헤테로아릴옥시, 아릴싸이오 또는 헤테로아릴싸이오를, R⁹∼R¹²는 수소, 알킬, 알켄일, 알킨일, 알콕시, 알켄일옥시, 알킨일옥시, 알킬싸이오, 알킨일싸이오 또는 아릴을 나타낸다.)There is provided a thiophene derivative represented by the following formula (1).

Wherein R ¹ to R ⁴ are independently selected from alkyl, alkenyl, alkynyl, alkoxy, alkenyloxy, alkynyloxy, alkylthio, alkynylthio, aryloxy, heteroaryloxy, arylthio, or heteroarylthio, R ⁵ to R ⁸ are independently selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, alkoxy, alkenyloxy, alkynyloxy, alkylthio, alkynylthio, aryloxy, heteroaryloxy, arylthio, or heteroarylthio , R ⁹ to R ¹² represent hydrogen, alkyl, alkenyl, alkynyl, alkoxy, alkenyloxy, alkynyloxy, alkylthio, alkynylthio or aryl.

Description

TECHNICAL FIELD The present invention relates to thiophene derivatives, their use, and methods for preparing thiophene derivatives. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to thiophene derivatives,

The present invention relates to a thiophene derivative, its use, and a process for preparing a thiophene derivative. More specifically, the 2-thienyl group having a substituent at at least three positions is substituted with a 2-, 3-, Substituted thiophene derivatives, their use as charge-transporting materials, and methods for preparing thiophene derivatives.

In the organic electroluminescence (hereinafter referred to as organic EL) element, a charge transporting thin film made of an organic compound is used as a light emitting layer or a charge injecting layer. Particularly, the hole injecting layer is responsible for transferring charges between the anode, the hole transporting layer, or the light emitting layer, and performs an important function for achieving low voltage driving and high brightness of the organic EL element.

The method of forming the hole injection layer is roughly classified into a dry process represented by a vapor deposition method and a wet process represented by a spin coating method. Comparing these processes, a thin film having a large surface area and a high flatness can be efficiently produced have. 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.

In view of such circumstances, the inventors of the present invention have found that a charge-transporting material which can be applied to various wet processes and which provides a thin film capable of realizing excellent EL element characteristics when applied to a hole injection layer of an organic EL device, Have developed compounds having good solubility in organic solvents (see, for example, Patent Documents 1 to 4).

International Publication No. 2008/032616 International Publication No. 2008/129947 International Publication No. 2006/025342 International Publication No. 2010/058777

INDUSTRIAL APPLICABILITY The present invention can provide an organic EL device which can exhibit good solubility in an organic solvent as well as an organic EL device having excellent lifetime characteristics when it is thinned and applied to a hole injection layer, Anthracene derivatives, and derivatives thereof.

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted intensive investigations in order to achieve the above object and as a result have found that a thiophene derivative having high solubility in an organic solvent and a thin film obtained from a varnish prepared by dissolving it in an organic solvent together with a dopant The present inventors have found that excellent lifetime characteristics can be realized when the thin film is applied to a hole injection layer of an organic EL device having charge transportability and completed the present invention.

That is, the present invention provides the following thiophene derivatives and their use and methods for preparing thiophene derivatives.

1. A thiophene derivative represented by the following formula (1).

(Wherein, R ¹ ~R ⁴ are, each independently optionally substituted, an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ¹ may carbon atoms which is optionally substituted by alkynyl, alkoxy group, alkenyloxy group, Z ¹ of 2 to 20 carbon atoms which may be substituted with Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ¹ of the 2 to 20 carbon atoms 20 alkynyl of acryloyloxy group, come alkylthio of 1 to 20 carbon atoms which may be substituted with Z ^1, Im coming alkenyl of 2 to 20 carbon atoms which may be substituted with Z ^1, carbon atoms which may be substituted with Z ¹ 2 to 20 the alkynyl Im come, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, hetero aryloxy group of 2 to 20 carbon atoms which may be substituted with Z ^2, carbon atoms which may be substituted with Z ² 6-20 aryl can be substituted with Cy import or Z ² Represents a heteroaryl Im come in Figure 2 to 20 carbon atoms which,

R ⁵ ~R ⁸ are, each independently, a hydrogen atom, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may C2-C20 alkynyl, alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, the carbon atoms that may be substituted with Z ¹ 2 to 20 An alkynyloxy group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkylthio group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkenylthio group of 2 to 20 carbon atoms which may be substituted with Z ¹ , alkynyl Im come, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, of 2 to 20 carbon atoms which may be substituted with Z ² hetero aryloxy, substituted with Z ² of 6 to 20 carbon atoms which may An arylthio group or Z < ² > Or a heteroarylthio group having 2 to 20 carbon atoms,

When R ⁵ to R ⁸ are not hydrogen atoms, R ¹ and R ⁵ , R ² and R ⁶ , R ³ and R ⁷ and / or R ⁴ and R ⁸ may be bonded to each other to form a divalent group,

~R ⁹ R ¹² are, each independently, a hydrogen atom, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may C2-C20 alkynyl, alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, the carbon atoms that may be substituted with Z ¹ 2 to 20 An alkynyloxy group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkylthio group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkenylthio group of 2 to 20 carbon atoms which may be substituted with Z ¹ , An alkynylthio group or an aryl group having 6 to 20 carbon atoms which may be substituted with Z < ² >

Z ¹ represents a halogen atom, an alkoxy group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, an alkynyloxy group having 2 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms An alkynylthio group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a heteroaryloxy group having 2 to 20 carbon atoms, an arylthio group having 6 to 20 carbon atoms, A heteroarylthio group having 1 to 20 carbon atoms,

Z ² represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, An alkylthio group having 1 to 20 carbon atoms, an alkenylthio group having 2 to 20 carbon atoms, an alkynylthio group having 2 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a heteroatom having 2 to 20 carbon atoms An arylthio group having 6 to 20 carbon atoms, or a heteroarylthio group having 2 to 20 carbon atoms.

2. Even if R ¹ ~R ^4, is replaced with, each independently, an alkoxy group, an alkenyloxy group of 2 to 20 carbon atoms which may be substituted with Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, Z ¹ carbon atoms, alkynyl of 2 to 20 is acryloyloxy group, come alkylthio of 1 to 20 carbon atoms which may be substituted with Z ^1, Im coming alkenyl of 2 to 20 carbon atoms which may be substituted with Z ^1, which may be substituted with Z ¹ Import 2 to 20 carbon atoms of Cy alkynyl, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, hetero aryloxy group of 2 to 20 carbon atoms which may be substituted with Z ^2, Z ^2, which may be substituted with An arylthio group having 6 to 20 carbon atoms or a heteroarylthio group having 2 to 20 carbon atoms which may be substituted with Z ² .

3. R ⁵ ~R ⁸ are, each independently, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms that may be substituted with hydrogen atoms, Z ¹ Or an alkoxy group having 1 to 20 carbon atoms which may be substituted with Z &^lt; 1 >.

4. The compound according to claim ¹ , wherein R ⁹ to R ¹² each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may be substituted with Z ¹ , an alkenyl group having 2 to 20 carbon atoms which may be substituted with Z ¹ , A thiophene derivative of any one of 1 to 3 which is an alkynyl group having 2 to 20 carbon atoms.

5. A process for producing a thiophene derivative of 1, characterized in that a thiophene compound represented by the following formula (2) and a trialkylstannyl thiophene compound represented by the formula (3) to (6) are reacted in the presence of a catalyst Way.

(Wherein each Hal independently represents a halogen atom or a similar group, and R ^a independently represents an alkyl group having 1 to 20 carbon atoms, R ¹ to R ¹² are as defined above.)

6. A charge-transporting material comprising a thiophene derivative of any one of 1 to 4.

7. A charge-transporting varnish comprising any one of thiophene derivatives, dopants, and organic solvents.

8. A charge transporting thin film fabricated using a charge transporting varnish.

9. A charge-transporting thin film comprising a thiophene derivative of any one of claims 1 to 4.

10. An electronic device comprising at least one charge transporting thin film of 8 or 9.

11. An organic electroluminescent device comprising at least one charge transporting thin film of 8 or 9.

12. The organic electroluminescent device according to 11, wherein the charge transport thin film is a hole injection layer or a hole transport layer.

The thiophene derivative 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 a hole injection layer of an organic EL device, an organic EL device having excellent lifetime characteristics can be obtained.

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

[Thiophene derivatives]

The thiophene derivative according to the present invention is represented by the following formula (1).

Wherein, R ¹ ~R ⁴ are, each independently, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may C2-C20 alkynyl, alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, the carbon atoms that may be substituted with Z ¹ 2 to 20 An alkynyloxy group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkylthio group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkenylthio group of 2 to 20 carbon atoms which may be substituted with Z ¹ , alkynyl Im come, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, of 2 to 20 carbon atoms which may be substituted with Z ² hetero aryloxy, substituted with Z ² of 6 to 20 carbon atoms which may Arylthio group or Z < ² > Represents a heteroarylthio group having 2 to 20 carbon atoms.

R ⁵ ~R ⁸ are, each independently, a hydrogen atom, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may C2-C20 alkynyl, alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, the carbon atoms that may be substituted with Z ¹ 2 to 20 An alkynyloxy group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkylthio group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkenylthio group of 2 to 20 carbon atoms which may be substituted with Z ¹ , alkynyl Im come, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, of 2 to 20 carbon atoms which may be substituted with Z ² hetero aryloxy, substituted with Z ² of 6 to 20 carbon atoms which may An arylthio group or Z < ² > Or a heteroarylthio group having 2 to 20 carbon atoms which may be substituted.

When R ⁵ to R ⁸ are not hydrogen atoms, R ¹ and R ⁵ , R ² and R ⁶ , R ³ and R ⁷ and / or R ⁴ and R ⁸ may combine with each other to form a divalent group.

~R ⁹ R ¹² are, each independently, a hydrogen atom, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may C2-C20 alkynyl, alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, the carbon atoms that may be substituted with Z ¹ 2 to 20 An alkynyloxy group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkylthio group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkenylthio group of 2 to 20 carbon atoms which may be substituted with Z ¹ , Alkynylthio group or an aryl group having 6 to 20 carbon atoms which may be substituted with Z < ² >.

Z ¹ represents a halogen atom, an alkoxy group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, an alkynyloxy group having 2 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms An alkynylthio group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a heteroaryloxy group having 2 to 20 carbon atoms, an arylthio group having 6 to 20 carbon atoms, Lt; / RTI >

Z ² represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, An alkylthio group having 1 to 20 carbon atoms, an alkenylthio group having 2 to 20 carbon atoms, an alkynylthio group having 2 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a heteroatom having 2 to 20 carbon atoms An arylthio group having 6 to 20 carbon atoms, or a heteroarylthio group having 2 to 20 carbon atoms.

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

The alkyl group having 1 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a s- , n-octyl group, n-nonyl group, n-decyl group, and other linear or branched alkyl groups having 1 to 20 carbon atoms; 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,

The alkenylene group having 2 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of the alkenyl group include an ethynyl group, an n-1-propenyl group, an n-2-propenylene group, a 1-methylethenyl group, Methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenylene group, 1-methyl- -1-pentenyl group, n-1-decenyl group, n-1-eicosenyl group and the like.

The alkynyl group having 2 to 20 carbon atoms may be any of linear, branched, and cyclic. Specific examples of the alkynyl group include ethynyl, n-1-propynyl, n-2-propynyl, n-1-butynyl, n-2-butynyl, N-pentyl group, n-pentyl group, n-pentyl group, 1-methyl-n-butynyl group, 2-methyl- N-propynyl group, n-1-decynyl group, n-1-pentadecynyl group, n-1-eicosyl group New Diary and so on.

The alkoxy group having 1 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of the alkoxy group include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, s-butoxy, A linear or branched alkoxy group having 1 to 20 carbon atoms such as a n-heptyloxy group, a n-heptyloxy group, an n-octyloxy group, an n-nonyloxy group, and a n-decyloxy group; A cyclopentyloxy group, a cyclohexyloxy group, a cycloheptyloxy group, a cyclooctyloxy group, a cyclononyloxy group, a cyclodecyloxy group, a bicyclobutyloxy group, a bicyclopentyloxy group, a cyclohexyloxy group, And cyclic alkoxy groups having 3 to 20 carbon atoms such as a bicyclohexyloxy group, a bicycloheptyloxy group, a bicyclooctyloxy group, a bicyclononyloxy group, and a bicyclodesyloxy group.

The alkenyloxy group having 2 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of the alkenyloxy group include ethynyloxy groups such as an ethynyloxy group, an n-1-propenyloxy group, an n-2-propenyloxy group, a 1-methylethenioxy group, Methyl-1-propenyloxy group, 2-methyl-1-propenyloxy group, 1-ethylheptanoyloxy group, , 1-methyl-2-propenyloxy group, n-1-pentenyioxy group, n-1-decenoyloxy group and n-1-eicoseneoxy group.

The alkynyloxy group having 2 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of the alkynyloxy group include ethynyloxy group, n-1-propynyloxy group, n-2-propynyloxy group, n-1-butynyloxy group, n- N-pentynyloxy group, n-4-pentynyloxy group, 1-methyl-n-pentynyloxy group, N-butynyloxy group, n-1-hexynyloxy group, n-1-pentynyloxy group, N-1-octadecyloxy group, n-1-pentadecenyloxy group, n-1-eicosynyloxy group and the like.

The alkylthio group having 1 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of alkylthio include methylthio, ethylthio, n-propylthio, isopropylthiothio, n-butylthio, isobutylthio, s-butylthio, A linear or branched alkylthio group having 1 to 20 carbon atoms, such as pentylthio group, n-hexylthio group, n-heptylthio group, n-octylthio group, n-nonylthio group, Cyclopentylthio, cyclopentylthio, cyclopentylthio, cyclopentylthio, cyclopentylthio, cyclopentylthio, cyclopentylthio, cyclohexylthio, cycloheptylthio, cyclooctylthio, cyclononylthio, cyclodecylthio, bicyclobutylthio, And cyclic alkylthio groups having 3 to 20 carbon atoms such as bicyclohexylthio group, bicycloheptylthio group, bicyclooctylthio group, bicyclooctylthio group, and bicyclodecylthio group.

The alkenylthio group having 2 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of alkenyl thio groups include ethynylthio, n-1-propenylthio, n-2-propenylthio, 1-methylethenylsulfoxide, n-1- Methyl-2-propenyl thioglycate, 1-ethyl ethenyl thioglycate, 1-methyl-1-propenyl thioglycollate, Methyl-2-propenyl thio group, n-1-pentenyl thio group, n-1-decenoyl thio group, n-1-eicosyl thio group, and the like.

The alkynylthio group having 2 to 20 carbon atoms may be any of linear, branched and cyclic. Specific examples of the alkynylthio group include ethynylthio group, n-1-propynylthio group, n-2-propynylthio group, n-1-butynylthio group, n- N-1-pentynylthio, n-2-pentynylthio, n-3-pentynylthio, n-4-pentyne, 1-methyl-n-butylanylthio, 2-methyl-n-butylanylthiogly, 3-methyl-n- n-1-hexynylthiogly, n-1-decynylthiogly, n-1-pentadecynylthiogly, and n-1-eicosynylthiogly.

The carbon number of the alkyl group, alkenyl group, alkynyl group, alkoxy group, alkenyloxy group, alkynyloxy group, alkylthio group, alkenylthio group and alkynylthio group is preferably 12 or less, more preferably 6 or less, Or less.

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.

Specific examples of the aryloxy group having 6 to 20 carbon atoms include a phenyloxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 1-anthryloxy group, a 2-anthryloxy group, Phenanthryloxy group, 2-phenanthryloxy group, 3-phenanthryloxy group, 4-phenanthryloxy group, 9-phenanthryloxy group and the like.

Specific examples of the heteroaryloxy group having 2 to 20 carbon atoms include a 2-thienyloxy group, a 3-thienyloxy group, a 2-furanyloxy group, a 3-furanyloxy group, a 2-oxazolyloxy group, Thioxoazoyloxy group, a 4-thiazolyloxy group, a 5-thiazolylthio group, a 5-thiazolylthio group, a 4-thiazolylthio group, 3-isothiazolyloxy group, 4-isothiazolyloxy group, 5-isothiazolyloxy group, 2-imidazolyloxy group, 4-imidazolyloxy group, 2-pyridyloxy group, 3- Pyridyloxy group, 4-pyridyloxy group, and the like.

Specific examples of the arylthio group having 6 to 20 carbon atoms include phenylthio group, 1-naphthylthio group, 2-naphthylthio group, 1-anthrylthio group, 2-anthrylthio group, Phenanthrylthio group, 2-phenanthrylthio group, 3-phenanthrylthio group, 4-phenanthrylthio group, 9-phenanthrylthio group and the like.

Specific examples of the heteroarylthio group having 2 to 20 carbon atoms include 2-thienylthio group, 3-thienylthio group, 2-furanylthio group, 3-furanylthio group, 2- Thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl, Isothiazolyl thiourea, 5-isothiazolyl thiourea, 2-imidazolyl thiourea, 4-isothiazolyl thiourea, 4-isothiazolyl thiourea, Imidazolylthioglycidyl, 2-pyridylthioglycidyl, 3-pyridylthioglycidyl, 4-pyridylthioglycidyl and the like.

The number of carbon atoms of the aryl group, aryloxy group, heteroaryloxy group, arylthio group and heteroarylthio group is preferably 14 or less, more preferably 10 or less, and even more preferably 6 or less.

R ¹ ~R ⁴ As the alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, alkynyl of 2 to 20 carbon atoms which may be substituted with Z ¹ acryloyloxy group, optionally substituted by Z ¹ to 20 carbon atoms, particularly of 2 to 20 carbon atoms comes to be an alkylthio, alkenyl come Sy of 2 to 20 carbon atoms which may be substituted with Z ^1, carbon atoms which may be substituted with Z ¹ carbon atoms which may be substituted with a C2-C20 alkynyl Im come, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, hetero aryloxy group of 2 to 20 carbon atoms which may be substituted with Z ² of a, Z ² which may have 2 to 20 carbon atoms heteroaryl Im coming of which may be optionally substituted by coming aryl or Cy Z ² of 6 to 20 is preferable, and a substituted alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ¹ An alkene having 2 to 20 carbon atoms Heteroaryl oxy group, alkynyl-yloxy group, 2 to 20 carbon atoms which may be substituted with a carbon number of 6 to 20 aryloxy group, or Z ² of which may be substituted with Z ² of 2 to 20 carbon atoms which may be substituted with Z ¹ oxy More preferably an alkoxy group having 1 to 20 carbon atoms which may be substituted with Z ¹ or an aryloxy group having 6 to 20 carbon atoms which may be substituted with Z ² .

In addition, R ⁵ ~R ⁸ as the number of carbon atoms that may be substituted by an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms that may be substituted with hydrogen atoms, Z ¹ 2-20 the alkynyl or of 1 to 20 carbon atoms which may be substituted with Z ¹ alkoxy group is preferred, and of 1 to 20 carbon atoms that may be substituted with an alkyl group or Z ¹ of 1 to 20 carbon atoms that may be substituted with hydrogen atoms, Z ¹ More preferably an alkoxy group, still more preferably a hydrogen atom or an alkoxy group having 1 to 20 carbon atoms which may be substituted with Z ¹ , and a hydrogen atom is most preferable.

R ⁹ ~R ¹² Examples of 2 to 20 carbon atoms which may be substituted with Z ^1, or an alkenyl group of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms that may be substituted with hydrogen atoms, Z ¹ An alkynyl group is preferable, an alkyl group having 1 to 20 carbon atoms which may be substituted with a hydrogen atom or Z ¹ is more preferable, and a hydrogen atom is most preferable.

In R ¹ to R ¹² , the substituent Z ¹ is preferably a halogen atom or an aryl group having 6 to 14 carbon atoms, more preferably a halogen atom or a phenyl group, and is not present (that is, an unsubstituted) It is optimal.

The substituent Z ² is preferably a halogen atom or an alkyl group having 1 to 20 carbon atoms, more preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms, and is not present (that is, unsubstituted).

From the viewpoint of ease of synthesis, it is preferable that the thiophene derivative represented by the formula (1) has the same structure as the 2-thienyl group having a substituent at the 3-position. That is, it is preferable that all of R ¹ to R ⁴ in the formula (1) are the same group, and R ⁵ to R ⁸ are all the same groups and R ⁹ to R ¹² are all the same group.

Specific examples of the thiophene derivative represented by the formula (1) are shown below, but the present invention is not limited thereto. In the formula, Me, Et, Pr, Bu, Pen and Hex each represent a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group and a hexyl group.

[Production method of thiophene derivative]

The thiophene derivative of the present invention can be produced, for example, by reacting a thiophene compound represented by formula (2) with a trialkylstannylthiophene compound represented by formulas (3) to (6) have.

(Wherein each Hal independently represents a halogen atom or a similar group, and R ^a independently represents an alkyl group having 1 to 20 carbon atoms, R ¹ to R ¹² are 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.

Examples of the trialkylstannyl group include trimethylstannyl, triethylstannyl, tri-n-propylstannyl, triisopropylstannyl, tri-n-butylstannyl, tri- , A trioctylstannyl group, and an n-butyldimethylstannyl group.

Specific examples of the thiophene compound represented by the formula (2) include tetrachlorothiophene, tetrabromothiophene, tetraiodothiophene and the like, but are not limited thereto.

Examples of the trialkylstannyl thiophene compounds represented by the formulas (3) to (6) include 3-methoxy-2- (tri-n-butylstannyl) thiophene, 3-methylthio- (Tert-butylstannyl) thiophene, 3-hexyl- (tri-n-butylstannyl) thiophene, 3,4-ethylenedioxy- , But are not limited to these.

The charging ratio of the thiophene compound represented by the formula (2) to the trialkylstanthienthiophene compound represented by the formulas (3) to (6) can be calculated by the formula (3) with respect to the thiophene compound represented by the formula (2) ) To (6) can be each 1 equivalent or more, but 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; (Triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ), bis (triphenylphosphine) dichloropalladium (Pd (PPh ₃ ) ₂ Cl ₂ ), bis (benzylideneacetone) palladium ) _2), tris (dibenzylidene acetone) dipalladium (Pd ₂ (dba) _3), bis (tri -t- butylphosphine) palladium (Pd (Pt-Bu _{3) 2),} and the like palladium catalysts, such as have. These catalysts may be used singly 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 may be about 0.01 to 0.2 mol, preferably about 0.05 mol, per 1 mol of the thiophene compound represented by the formula (2).

When a ligand is used, the amount of the ligand to be used may be 0.1 to 5 equivalents relative to the metal complex to be 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, Carbon, etc.), aromatic hydrocarbons (benzene, nitrobenzene, toluene, o-xylene, m-xylene, p-xylene and mesitylene), halogenated aromatic hydrocarbons (chlorobenzene, bromo Benzene, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, etc.), ethers (diethylether, diisopropylether, tert- butylmethylether, tetrahydrofuran, dioxane, Dimethoxyethane, 1,2-diethoxyethane, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, cyclohexanone, etc.), amides N, N-dimethylformamide, N, N-dimethylacetamide, etc.), lactam and lactones (N-methylpyrrolidone, (N, N-dimethylimidazolidinone, tetramethylurea and the like), sulfoxides (dimethylsulfoxide, sulfolane and the like), nitriles (acetonitrile, propionitrile, Etc.). 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 of the solvent to the boiling point, but is preferably about 0 to 200 占 폚, and more preferably 20 to 150 占 폚.

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

The method for producing the trialkylstannyl thiophene compound represented by the formulas (3) to (6) used in the synthesis of the thiophene derivative of the present invention is not particularly limited, and for example, it can be synthesized according to the following reaction formula (Scheme 1). In addition, the following reaction scheme shows a method for synthesizing a trialkylstannyl thiophene compound represented by the formula (3), but the trialkylstannyl thiophene compounds represented by the formulas (4) to (6) , Lithiation of the corresponding thiophene compound, and reaction of the resulting thiophene compound with a halogenated trialkyltin.

(Wherein R ¹ , R ⁵ , R ⁹ and R ^a are as defined above, and X represents a halogen atom.)

In particular, this synthesis method is based on the synthesis of a thiophene compound (formula (7 ")) in which the 2 and 5 positions are unsubstituted and have 4-position substituents at the 3 position and the 4 position is substituted with unsubstituted or non- 2 position can be highly selectively lithiated, particularly in the synthesis of a thiophene compound represented by the formula (7) (Scheme 2).

(Wherein R ^a , R and X have the same meanings as defined above, R ¹³ represents a cyano substituent, and R ¹⁴ represents a hydrogen atom or a non-conjugated substituent.)

A substitutional substituent refers to a substituent having an atom capable of coordinating to a lithium atom such as oxygen, nitrogen or sulfur atom, and a non-substituent means a substituent containing no such atom.

Times alkynyl acryloyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, an alkenyloxy group of 2 to 20 carbon atoms which may be substituted with Z ^1, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ¹ as the satellite substituent Import, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, hetero aryloxy group of 2 to 20 carbon atoms which may be substituted with Z ^2, alkylthio of 1 to 20 carbon atoms which may be substituted with Z ^1, Im coming alkenyl of 2 to 20 carbon atoms which may be substituted with Z ^1, Z ¹ is replaced with import alkynyl Sy of 2 to 20 carbon atoms which may, of 6 to 20 carbon atoms which may be substituted with Z ² coming aryl or Cy And a heteroarylthio group having 2 to 20 carbon atoms which may be substituted with Z < ² >.

Examples of non-coordination substituent include an alkynyl of 2 to 20 carbon atoms which may be substituted with Z ^1, or an alkenyl group of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ¹ have.

An alkenyl group, an alkynyloxy group, an alkynyloxy group, an aryloxy group, a heteroaryloxy group, an alkylthio group, an alkenylthio group, an alkynylthio group, an arylthio group, a heteroarylthio group, an alkyl group, Diazo and the substituents Z ¹ and Z ^{2 of} these may be the same as those described above.

Examples of the thiophene compound represented by the formula (3 '') include 3-methylthiophene, 3-ethylthiophene, 3-n-propylthiophene, 3-n-butylthiophene, 3-methoxythiophene, 3-ethoxythiophene, 3-n-propoxythiophene, 3,4-dimethoxythiophene, 3,4-diethoxythiophene, 3,4-ethylenedioxythiophene, 3-methylthiothiophene, and the like, but are not limited thereto.

Examples of the thiophene compound represented by the formula (7 '') include 3-methoxythiophene, 3-ethoxythiophene, 3-n-propoxythiophene and 3-methylthiothiophene. .

Examples of the lithiating agent include organic lithium compounds such as n-butyllithium, s-butyllithium, t-butyllithium, isobutyllithium, methyllithium, n-propyllithium, isopropyllithium, Butyl lithium, trimethylsilylmethyl lithium, propynyl lithium, 2-ethylhexyl lithium, 2,4-pentadienyl lithium, allyl lithium, 1,3-butadienyl- Alkyl lithium or aryl lithium compounds such as methyl lithium, 1-methoxyallyl lithium, trichloromethyl lithium, pentyl lithium, phenyl lithium and 2,6-dimethoxy phenyl lithium, lithium hexamethyldisilazide, lithium diisopropyl Lithium amide compounds such as lithium iodide, amide, lithium piperide, lithium diethylamide, lithium tetramethyl piperide, lithium bis (dimethylethylsilyl) amide, lithium dimethylamide and lithium dicyclohexylamide. .

As the halogenated trialkyl tin, there is no particular limitation as long as it is possible to introduce a trialkylstannyl group, but tri (n-butyl) tin chloride is suitable in view of the availability, handleability and reactivity. The halogenated trialkyl tin can be synthesized by a known method (for example, the method described in Chem. Commun., 2001, 1840-1841), but it is also available as a commercial product.

The charging ratio of the thiophene compound represented by the formula (3 '') or the thiophene compound represented by the formula (7 '') to the lithiation agent can be represented by the thiophene compound represented by the formula (3 ' ), The amount of the lithiating agent can be about 1 to about 1.5 equivalents, but about 1.1 equivalents is suitable for the thiophene compound.

Further, the charging ratio of the thiophene compound represented by the formula (3 ') or the thiophene compound represented by the formula (7') and the halogenated trialkyl tin may be the thiophene compound represented by the formula (3 ' '), The halogenated trialkyl tin can be used in an amount of about 1 to about 5 equivalents, preferably about 1.2 equivalents.

The reaction temperature may be appropriately set in the range from the melting point to the boiling point of the solvent to be used, and is preferably about -78 to 20 占 폚, and more preferably -20 to 0 占 폚.

After completion of the reaction, the desired thiophene derivative can be obtained by post treatment in accordance with the conventional method.

The reaction solvent is not particularly limited as long as it does not inhibit the reaction, but a chain or cyclic ether is preferred. In particular, in Scheme 2, from the viewpoint of improving the lithiation selectivity at the 2-position and improving the yield of the thiophene compound represented by the formula (7), the chain ether is more preferable, and the chain ether having at least one branch chain is Furthermore preferred.

Examples of the chain ether include linear or branched straight chain alkyl groups such as diethyl ether, diisopropyl ether, di-n-butyl ether, t-butyl methyl ether and cyclopentyl methyl ether, Or asymmetric dialkylethers, but are not limited to these. Examples of the cyclic ether include tetrahydrofuran, tetrahydrofuran, hexamethylene oxide, heptamethylene oxide, and the like, but are not limited thereto.

Of these, diisopropyl ether, t-butyl methyl ether and cyclopentyl methyl ether are particularly preferable from the viewpoint of the lithiation selectivity at the 2-position.

[Charge transport varnish]

The charge-transporting varnish of the present invention comprises a charge-transporting material comprising a thiophene derivative represented by formula (1) and an organic solvent, but may contain a dopant if necessary in order to improve the charge transport ability and the like.

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

Examples of the inorganic dopant 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.

Examples of organic based dopants include benzenesulfonic acid, tosylic acid, p-styrenesulfonic acid, 2-naphthalenesulfonic acid, 4-hydroxybenzenesulfonic acid, 5-sulfosalicylic acid, p-dodecylbenzenesulfonic acid, Dodecylbenzenesulfonic acid, 2,5-dihexylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid, 6,7-dibutyl-2-naphthalenesulfonic acid, dodecylnaphthalenesulfonic acid, 3-dodecyl-2-naphthalenesulfonic acid, hexylnaphthalenesulfonic acid , 4-hexyl-1-naphthalenesulfonic acid, octylnaphthalenesulfonic acid, 2-octyl-1-naphthalenesulfonic acid, hexylnaphthalenesulfonic acid, 7-hexyl-1-naphthalenesulfonic acid, Naphthalenesulfonic acid, dinonylnaphthalenesulfonic acid, 2,7-dinonyl-4, 5-naphthalenesulfonic acid, WO 2005/000832 Benzodioxane disulfonic acid compounds, arylsulfonic acid compounds described in WO 2006/025342, arylsulfonic acid compounds described in International Publication No. 2009/096352 Aryl sulfonic acid compounds such as acid compounds, polystyrene sulfonic acid; Vialylsulfonic acid 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) .

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

Among these dopants, heteropoly acid is suitable. By using heteropoly acid as a dopant, it is possible to obtain not only a fixation hole capacity from a transparent electrode typified by indium tin oxide (ITO) and indium zinc oxide (IZO) but also a charge transport property from a metal anode represented by aluminum This excellent thin film can be obtained.

The heteropoly acid typically has a Keggin type represented by the formula (A1) or a Dawson type chemical structure represented by the formula (A2), wherein the heteroatom is located at the center of the molecule, and the vanadium (V), molybdenum (Mo), tungsten (W), and other oxides of different kinds. As the oxo acid of such a different element, oxo acid of mainly silicon (Si), phosphorus (P) and arsenic (As) can be mentioned.

Specific examples of the heteropoly acid include inorganic molybdic acid, silicon molybdic acid, tungstic acid, silicon tungstic acid, and tungstomolybdic acid. These may be used singly or in combination of two or more. 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 is composed of one kind of heteropoly acid, the one kind of heteropoly acid is preferably tungstic acid or phospholipidic acid, more preferably tungstic acid. When the dopant is composed of two or more kinds of heteropoly acids, at least one of the two or more kinds of heteropoly acids is preferably tungstic acid or phospholipidic acid, more preferably tungstic acid.

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

That is, for example, generally a tungsten acid formula _{H 3 (PW 12 O 40)} · as nH _2O, mold ribs deneom acid there is respectively represented by the general formula _{H 3 (PMo 12 O 40)} · nH 2 O, in the quantitative analysis , The number of P (phosphorus), O (oxygen), W (tungsten) or Mo (molybdenum) in this equation may be large or small, and it may be a product obtained as a commercial product, Can be used in the present invention as long as they are synthesized. In this case, the mass of the heteropoly acid specified in the present invention is not the mass (pure tungstic acid content) of the pure tungstic acid in the synthetic material or the commercial product, but is in a form obtainable as a commercially available product and in a form which can be isolated by a known synthetic method, Means the total mass in a state including water or other impurities.

Also, arylsulfonic acid compounds can be suitably used as dopants. In particular, the arylsulfonic acid compound represented by the formula (B1) or (B2) is preferable.

In the formula (B1), A ¹ represents -O- or -S-, preferably -O-. A ² represents a naphthalene ring or an anthracene ring, and 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 group bonded to A ² , and is an integer satisfying ^1? q? ⁴ , and 2 is suitable.

In formula (B2), A ^{4 to} A ⁸ each independently represents 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, And at least three of A ^{4 to} A ⁸ are halogen atoms. r is an integer satisfying 1? r? 4, preferably 2 to 4, and more preferably 2, as the number of sulfonic acid groups bonded to the naphthalene ring.

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 1-perfluoropropenyl group, a perfluoroallyl group, and a perfluorobutenyl group.

Examples of the halogen atom and the alkyl group having 1 to 20 carbon atoms include the same ones as 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. 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, or an alkenyl fluoride group having 2 to 5 carbon atoms, and at least three of A ^{4 to} A ⁸ are fluorine atoms Is more preferable. Further, it is further preferable that A ⁴ , A ⁵ and A ⁸ are fluorine atoms, and it is more preferably a hydrogen atom, a fluorine atom, a cyano group, a perfluoroalkyl group having 1 to 5 carbon atoms or a perfluoroalkylene group having 1 to 5 carbon 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 hydrogen atoms of the alkenyl group are substituted with fluorine atoms.

Specific examples of suitable aryl sulfonic acid compounds as other dopants in the present invention include, but are not limited to, the following.

When the charge-transporting varnish of the present invention contains a dopant, the amount of the dopant to be used can not be uniformly determined in consideration of the type of the dopant and the degree of desired charge transportability. However, Is within the range of about 0.01 to 50 per 1 charge-transporting material (hereinafter, simply referred to as charge-transporting material) composed of a thiophene derivative.

In particular, when heteropoly acid is used as a dopant, the heteropoly acid is used in an amount of about 0.5 to 30.0, preferably about 1.0 to 20.0, more preferably about 2.0 to 15.0, still more preferably about 3.0 To about 12.0, and more preferably from about 4.0 to about 11.0, whereby a charge transporting thin film providing high brightness can be obtained with high reproducibility when used in an organic EL device.

On the other hand, when the arylsulfonic acid compound is used as the dopant, the arylsulfonic acid compound is preferably used in an amount of 0.05 to 15.0, preferably 0.10 to 10.0, more preferably 0.25 to 7.0, Is 0.50 to 5.0, and more preferably 0.75 to 3.0, a charge-transporting thin film which provides a high luminance when used in an organic EL device can be obtained with high reproducibility.

The charge transporting varnish of the present invention may also contain an organosilane compound. By including the organosilane, the ability to inject holes into the layer stacked to be in contact with the hole injection layer on the opposite side to the anode such as the hole transport layer or the light emitting layer can be enhanced, and as a result, higher luminance characteristics can be realized.

Examples of the organosilane compound include a dialkoxysilane compound, a trialkoxysilane compound, and a tetraalkoxysilane compound. These may be used singly or in combination of two or more.

Particularly, as the organosilane compound, a dialkoxysilane compound or a trialkoxysilane compound is preferable, and a trialkoxysilane compound is more preferable.

Examples of the dialkoxysilane compound, the trialkoxysilane compound and the tetraalkoxysilane compound include those represented by the formulas (C1) to (C3).

SiR '₂(OR)₂ (C1)

SiR '(OR) ₃ (C2)

Si (OR) ₄ (C3)

Wherein, R is, each independently, an alkyl group of 1 to 20 carbon atoms optionally substituted by Z ^3, Z ³ carbon atoms optionally substituted with C2-C20 alkenyl group, Z ³ of which may be optionally substituted 2-20 a represents an alkynyl group, a heteroaryl group of 2 to 20 carbon atoms which may be substituted with Z ⁴ with an aryl group of 6 to 20 carbon atoms which may be optionally substituted or Z ^4. R 'are, each independently, Z ⁵ to 20 carbon atoms in the alkyl group that may be substituted, the alkenyl of 2 to 20 carbon atoms which may be substituted with a group Z ^5, Z ⁵ alkynyl of 2 to 20 carbon atoms which may be substituted by It represents a group, a heteroaryl group of 2 to 20 carbon atoms that may be substituted with Z ⁶ with an aryl group of 6 to 20 carbon atoms which may be optionally substituted or Z ^6.

Z ³ represents a halogen atom, a heteroaryl group of 2 to 20 carbon atoms which may be substituted with Z ⁷ of 6 to 20 carbon atoms which may be substituted with an aryl group, or Z to ^7.

Z ⁴ is a halogen atom, Z ⁷ to 20 carbon atoms in the alkyl group which may be substituted with, Z ⁷ alkynyl of 2 to 20 carbon atoms which may be substituted with a C2-C20 alkenyl group, or Z ⁷ of which may be substituted with a group .

Z ⁵ is a halogen atom, Z is substituted with ⁷ of 6 to 20 carbon atoms which may aryl group, a heteroaryl group of 2 to 20 carbon atoms optionally substituted by Z ^7, epoxy cyclohexyl group, glycolic seed oxy group, meta (-NHCONH ₂ ), a thiol group, an isocyanate group (-NCO), an amino group, -NHY ¹ group or -NY ² Y ³ group.

Z ⁶ is a halogen atom, Z ⁷ to 20 carbon atoms in the alkyl group which may be substituted with, Z ⁷ of 2 to 20 carbon atoms which may be substituted with alkenyl, alkynyl of 2 to 20 carbon atoms which may be substituted with Z ⁷ (-NHCONH ₂ ), a thiol group, an isocyanate group (-NCO), an amino group, a -NHY ¹ group or a - (meth) acryloyloxy group, NY ² Y ³ group.

Y ¹ ~Y ³ are, each independently, an alkyl group of 1 to 20 carbon atoms optionally substituted by Z ^7, Z ⁷ carbon atoms which may be substituted with an alkenyl group, Z ⁷ of 2 to 20 carbon atoms which may be substituted with 2 to 20 represents an alkynyl group, a heteroaryl group of 2 to 20 carbon atoms which may be substituted with Z ⁷ of 6 to 20 carbon atoms which may be substituted with an aryl group, or Z ⁷ of the.

Z ⁷ represents a halogen atom, an amino group, a nitro group, a cyano group or a thiol group.

Examples of the halogen atom, the alkyl group having 1 to 20 carbon atoms, the alkenyl group having 2 to 20 carbon atoms, the alkynyl group having 2 to 20 carbon atoms, and the aryl group having 6 to 20 carbon atoms in the formulas (C1) to (C3) . 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, a 4-oxazolyl group, Isothiazolyl group, 4-isothiazolyl group, 4-isothiazolyl group, 4-isothiazolyl group, 4-isothiazolyl group, A diazo group, a diazo 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.

In R and R ', the number of carbon atoms of the alkyl 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 alkyl group R of 1 to 20 carbon atoms optionally substituted by Z ^3, Z ³ may be substituted with 2 to 20 carbon atoms in the alkenyl group or Z ⁴ is an aryl group of 6 to 20 carbon atoms which is optionally substituted preferably with and, Z ³ as the alkyl group having 1 to 6 carbon atoms which may be optionally substituted, a phenyl group which may be substituted with an alkenyl group, or Z ⁴ with a carbon number of 2 to 6, and more preferably, an alkyl group having 1 to 4 carbon atoms optionally substituted by Z ³ or Z ⁴ A phenyl group which may be substituted is further preferable, and a methyl group or an ethyl group which may be substituted with Z ³ is more preferable.

As R ', an alkyl group having 1 to 20 carbon atoms which may be substituted with Z ⁵ , or an aryl group having ⁶ to 20 carbon atoms which may be substituted with Z ⁶ is preferable, and an alkyl group having 1 to 10 carbon atoms which may be substituted with Z ⁵ or Z More preferably an aryl group having 6 to 14 carbon atoms which may be substituted with ¹ to ⁶ carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms which may be substituted with Z ⁵ or an aryl group having 6 to 10 carbon atoms which may be substituted with Z ⁶ , a phenyl group that may be substituted with an alkyl group or Z ⁶ group having 1 to 4 carbon atoms which is optionally substituted by a ⁵ are more preferred.

The plural Rs may be the same or different, and plural R 's may be the same or different.

Z ³ is preferably an aryl group having 6 to 20 carbon atoms which may be substituted with a halogen atom or Z ⁷ , more preferably a phenyl group which may be substituted with a fluorine atom or Z ⁷ (that is, ) Is optimal.

The Z ⁴ is preferably an alkyl group having 6 to 20 carbon atoms which may be substituted with a halogen atom or Z ⁷ , more preferably an alkyl group having 1 to 10 carbon atoms which may be substituted with a fluorine atom or Z ⁷ , (I. E., An unsigned one) is optimal.

On the other hand, Z ⁵ as a halogen atom, Z ⁷ phenyl group which may be substituted with, Z ⁷ furan group, epoxy cycloalkyl that may be substituted with a hexyl group, a glycol seed oxy group, methacryl oxy group, acryloxy group, yureyi pottery , thiol group, isocyanate group, an amino group, Z ⁷ is diphenyl amino group that may be substituted by phenyl group or Z ⁷ is optionally substituted by a preferred, more preferred halogen atom for the fluorine atom or does not exist will (I. E., Unsubstituted) is further preferred.

In addition, furan optionally substituted with a halogen atom, an alkyl group of 1 to 20 carbon atoms optionally substituted by Z ^7, Z ⁷ to Z ⁶ as group, epoxy cyclohexyl group, glycolic seed oxy group, methacryl oxy group, acryloxy group, yureyi pottery, thiol group, isocyanate group, an amino group, Z ⁷ is diphenyl amino group that may be substituted by phenyl group or Z ⁷ is optionally substituted preferably with, more preferably a halogen atom to the fluorine atom, or The nonexistent (i. E., Unsubstituted) is even more desirable.

As Z ⁷ , a halogen atom is preferable, and a fluorine atom or a non-existent one (that is, an unsubstituted one) is more preferable.

Specific examples of the organosilane compound usable in the present invention are shown below, but the present invention is not limited thereto.

Specific examples of the dialkoxysilane compound include dimethyldimethoxysilane, dimethyldiethoxysilane, methylethyldimethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, methylpropyldimethoxysilane, But are not limited to, dimethoxysilane, methylpropyldiethoxysilane, diisopropyldimethoxysilane, phenylmethyldimethoxysilane, vinylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxy 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane,? -Aminopropylmethyldiethoxysilane, N- (2-aminoethyl) aminopropylmethyldimethoxysilane,? - aminopropylmethyldiethoxysilane, Phosphorus, 3,3,3-trifluoropropylmethyl Email ethoxy there may be mentioned such as a silane.

Specific examples of the trialkoxysilane compound include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, Butyltrimethoxysilane, butyltrimethoxysilane, butyltrimethoxysilane, butyltrimethoxysilane, butyltrimethoxysilane, pentyltrimethoxysilane, pentyltrimethoxysilane, heptyltrimethoxysilane, heptyltrimethoxysilane, octyltrimethoxysilane, Hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethane, octadecyltrimethoxysilane, Octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, [gamma] -aminopropyltrimethoxysilane, [gamma] -aminopropyltrimethoxysilane, 3-Ami But are not limited to, n-propyltriethoxysilane,? -Glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane,? -Methacryloxypropyltrimethoxysilane,? -Meta (Tri (trifluoromethyl) phenyl) silane, dodecyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, triethoxysilane, (Triethoxysilyl) cyclohexane, perfluorooctylethyltriethoxysilane, triethoxyfluorosilane, tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane Pentafluorophenyltrimethoxysilane, pentafluorophenyltriethoxysilane, 3- (heptafluoroisopropoxy) propyltriethoxysilane, heptatafafluoro-1,1,2, 2-tetrahydrodecyltriethoxysilane, triethoxy-2-cyano (Triethoxysilyl) furan, and the like.

Specific examples of the tetraalkoxysilane compound include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and the like.

Of these, 3,3,3-trifluoropropylmethyldimethoxysilane, triethoxy (4- (trifluoromethyl) phenyl) silane, 3,3,3-trifluoropropyltrimethoxy Silane, perfluorooctylethyltriethoxysilane, pentafluorophenyltrimethoxysilane, pentafluorophenyltriethoxysilane, and the like are preferable.

When the charge-transporting varnish of the present invention contains an organosilane compound, the content thereof is preferably in the range of 0.1 to 50 mass% based on the total mass of the charge-transporting substance and the dopant, in view of maintaining the high charge- Considering that the reduction in the charge transporting property of the obtained thin film is suppressed and the hole injecting ability to the layer stacked to be in contact with the hole injection layer on the side opposite to the positive electrode such as the hole transporting layer or the light emitting layer is increased, Is preferably about 0.5 to 40 mass%, more preferably about 0.8 to 30 mass%, and still more preferably 1 to 20 mass%.

Further, in the charge transporting varnish of the present invention, other well-known charge-transporting materials may be used in addition to the above-described charge-transporting material comprising the thiophene derivative.

As the organic solvent to be used when preparing the charge transporting varnish, a solvent capable of dissolving a charge-transporting substance and a dopant can be used.

Examples of such a solubilizing solvent include N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, And an organic solvent such as ethylene glycol monomethyl ether can be used. These solvents may be used alone or in admixture of two or more, and the amount thereof may be 5 to 100 mass% with respect to the total solvent used in the varnish.

The charge-transporting substance and the dopant are both completely dissolved in the solvent, or are preferably uniformly dispersed, 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, the varnish can be adjusted according to the coating method to be used, which provides a highly flat thin film with good reproducibility.

The high viscosity organic solvent is not particularly limited, and examples thereof include cyclohexanol, ethylene glycol, ethylene glycol diglycidyl ether, 1,3-octyleneglycol, diethylene glycol, di Propylene glycol, triethylene glycol, tripropylene glycol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, propylene glycol, hex And cyanuric glycol. These solvents may be used alone or in combination of two or more.

The addition ratio of the high viscosity organic solvent to the entire solvent used in the varnish of the present invention is preferably within a range in which no solid is precipitated, and the addition ratio is preferably 5 to 80% by mass so long as no solid is precipitated.

Further, for the purpose of improving the hygroscopicity of the substrate, adjusting the surface tension of the solvent, adjusting the polarity, and adjusting the boiling point, other solvents are preferably used in an amount of 1 to 90 mass% And preferably from 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 0.5 to 5.0 mass%, and more preferably 1.0 to 3.0 mass%.

The charge-transporting thin film can be formed on the substrate by applying the charge-transporting varnish on 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 brushing method, an ink jet method, a spraying method and a slit coating method. It is desirable to adjust the viscosity and the surface tension.

In the case of using the varnish of the present invention, the firing atmosphere is not particularly limited, and a thin film having uniform film-forming surface and high charge transportability can be obtained not only in the atmosphere but also in an inert gas such as nitrogen or vacuum or vacuum.

The firing temperature is suitably set in the range of about 100 to 260 DEG C in consideration of the use of the obtained thin film and the degree of charge transportability imparted to the thin film to be obtained and the like. The obtained thin film is used as the hole injection layer of the organic EL device , 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 exhibiting a higher uniform film-forming property or promoting the reaction on a substrate. Heating may be performed using a suitable device such as, for example, a hot plate or an oven.

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.

[Organic EL device]

Materials and methods for producing OLED devices 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 manufacturing an OLED element 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 injection 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 transporting layer / hole blocking layer, and a cathode metal are sequentially deposited to form an OLED 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, alloys thereof, and the like.

(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' -tris (phenyl) amino] triphenylamine , 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) (p-phenylphenolate) aluminum (III) (BAlq), 4,4'-bis (2,2-diphenylvinyl) biphenyl, 9,10- Anthracene, 2-t-butyl-9,10-di (naphthalen-2-yl) anthracene, 2,7- (9,9-spirobifluoren-2-yl) -9,9-di (4-methylphenyl) fluorene, 2- (9,9-spirobifluorene-2-yl) -9,9-spirobifluorene, 2- [9,9-di (4-methylphenyl) -Fluorene-2-yl] -9,9-di (4-methylphenyl) fluorene, 2,2'-diphenylen-9,9-spirobifluorene, 1,3,5-tris Benzene, 9,9-bis [4- (pyrenyl) phenyl] -9H-fluorene, 2,2'-biphenyl (9,10- ), 2,7-diphenyl-9,9-spirobifluorene, 1,4-di (pyrene-1-yl) benzene, 1,3- Di (naphthalene-2-yl) perylene, tris [4- (4- (Naphthalen-1-yl) -N, N ', N'-tetramethyl- -Diphenyl- [1,1 ': 4', 1 '': 4 '', 1 '''- quaterphenyl] -4,4' Dibenzo {[f, f '] - 4,4', 7,7'-tetraphenyl} diindeno [1,2,3-cd: 1 ', 2', 3'-lm] perylene, 1- (7- (9,9'- bianthracene- 9,9-dihexyl-9H-fluoren-2-yl) pyrene, 1,3-bis (carbazole-9 (Carbazol-9-yl) benzene, 1,3,5-tris (carbazol-9-yl) benzene, 4,4 ' (Carbazol-9-yl) biphenyl (CBP), 4,4'-bis ( (Carbazol-9-yl) -9,9-dimethylfluorene, 2,2 ', 7,7'-dimethylbiphenyl, 2,7'- (Carbazol-9-yl) -9,9-di (p-tolyl) fluorene, 9,9-spirobifluorene, (Carbazol-9-yl) -9,9-spirobifluorene, 1,4-bis (carbazole-9-yl) (Triphenylsilyl) benzene, bis (4-N, N-diethylamino-2-methylphenyl) -4-methylphenylmethane, 2,7- (Triphenylsilyl) biphenyl, 9- (4-tert-butyldimethylsilyl) -9-tert-butylphenyl) -3,6-bis (triphenylsilyl) -9H-carbazole, 9- (9- (4-methoxyphenyl) -9H-fluorene-9-yl) -9H-carbazole, 2,6- 9-yl) phenyl) pyridine, triphenyl (4- (9-phenyl-9H-fluoren- Phenyl- 1 H-benzo [d] imidazol-2-yl) phenyl) -9H-fluorene-2- Amine, 3,5- bis (3- (9H-carbazol-9-yl) phenyl) pyridine, 9,9-spirobifluorene- -9- phenyl-9H-fluorene-9 (9H-carbazole), 3- (2,7-bis (diphenylphosphoryl) -9-phenyl-9H-carbazole, 4,4,8,8,12,12-hexa (p-tolyl) -4H-8H-12H-12C-aza dibenzo [cd, (4H-carbazol-9-yl) -1,10-phenanthroline, 2,2'-bis Bis (diphenylphosphoryl) dibenzo [b, d] thiophene, bis (2-methylphenyl) diphenylsilane, bis [3,5- Carbazole, 9- (4- (diphenylphosphoryl) -9- (2-ethyl-hexyl) Phenyl) -9H-carbazole, 3,6-bis [(3,5-diphenyl) phenyl] -9-phenylcarbazole And, by a luminescent dopant and a co-deposited, 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-phenyl Charmander Dean) (acetylacetonate) iridium (III) (Ir (ppy) ₂ (acac)), tris [2- (p- tolyl) Charmander Dean] iridium (III) (Ir (mppy) _3), 9,10-bis [N, N- di (p- tolyl) amino] anthracene, 9,10-bis [phenyl (m- tolyl) amino] anthracene, Bis (2-hydroxyphenyl) benzothiazolyl] zinc (II), N ¹⁰ , N ¹⁰ , N ¹⁰ , N ¹⁰ -tetra (p- 10'- ^{diamine, N 10, N 10, N} 10, N 10 - tetraphenyl -9,9'- bi anthracene -10,10'- diamine, N ^10, N ¹⁰ - ^10-diphenyl -N, N ^10-dimethyl -9,9'- bi-naphthalenyl anthracene -10,10'- diamine, 4,4'-bis (9-ethyl-3-carbazole crude vinylene) -1,1'-bar Bis [2- (3-N-ethylcarbazolyl) vinyl] benzene, 4,4'-bis [4 - (di-p-tolylamino) stearyl] biphenyl, 4- (di-p-tolylamino) -4 ' (2-pyridyl) phenyl- (2-carboxypyridyl)] iridium (III), 4,4'-bis [4- (diphenylamino) styryl] biphenyl, bis (4-difluorophenylpyridinate) tetrakis (1-pyrazolyl) borate iridium (III), N, N'-bis (naphthalen- Tris (9,9-dimethylfluorenylene), 2,7-bis {2- [phenyl (m-tolyl) amino] -9,9- (E) -2- (6 ((E) -4- (diphenylamino) styryl) naphthalen-2-yl) vinyl) amine, fac- iridium (III) tris (1-phenyl-3-methylbenzamide imidazolin-2-ilden -C, C ^2), mer- iridium (III) tris (1-phenyl-3-methylbenzamide 6-methyl-2- (4-tert-butylphenyl) imidazoline-2-ylidene-C, C ² ), 2,7- Yl) phenyl) benzo [d] thiazole, 1,4-di [4- (N, N (4- (9H-carbazol-9-yl) styryl) benzene, (E) -6- (4- (diphenylamino) styryl) (III), N, N-diphenyl naphthalene-2-amine, bis (2,4-difluorophenylpyridinate) (5- (pyridin- , (3-trifluoromethyl-5- (2-pyridyl) pyrazole) ((2,4-difluorobenzyl) diphenylphosphinate) iridium (III) (Benzyl diphenylphosphinate), iridium (III), bis (1- (2,4-difluorobenzyl) -3-methylbenzimide Thiazolium) -1,2,4-triazolate) iridium (III) (3- (trifluoromethyl) , Iridium (III), bis (4 ', 6' -difluorophenylpyridinate), bis (3'-trifluoromethyl-5- (4 ', 6'-difluorophenylpyridinate) (3,5-bis (trifluoromethyl) -2- (2'-pyridyl) (III), (Z) -6-mesitylene di (3-trifluoromethyl) -5- (2-pyridyl) -1,2,4- triazolate) butyl -N- (6- mesityl quinolin -2 (1H) - ilden) quinolin-2-amine _{-BF 2, (E) -2- (} 2- (4- ( dimethylamino) styryl) -6- 4-ylene) malononitrile, 4- (dicyanomethylene) -2-methyl-6-julolididyl-9- (Dicyanomethylene) -2-t-butyl-6- (1, 1, 7,7-tetramethylduluridyl-9- , 1,7,7-tetramethyldulurol-4-yl-vinyl) -4H-pyran, tris (dibenzoylmethane) phenanthroline europium (II I), 5,6,11,12-tetraphenylnaphthacene, bis (2-benzo [b] thiophen-2-yl-pyridine) (acetylacetonate) iridium (III) (9,9-dimethyl-9H-fluoren-2-yl) -isoquinolin-1-yl] (Acetylacetonate) iridium (III), bis [2- (9,9-dimethyl-9H-fluoren-2-yl) quinoline] (III), bis (hexafluorophosphate), tris (2-phenylquinoline) iridium (III), bis (2-phenylquinoline) Acetylacetonate) iridium (III), 2,8-di-t-butyl-5,11-bis (4-t- butylphenyl) -6,12-diphenyltetracene, bis (2-phenylbenzothiazole (Acetylacetonate) iridium (III), 5,10,15,20-tetraphenyltetrabenzoporpholine platinum, osmium (II) bis (3-trifluoromethyl-5- (2- (4-t-butylpyridyl) -1,2,4-triazo late (2-pyridyl) -pyrazolate) dimethylphenylphosphine, osmium Bis (3- (trifluoromethyl) -5- (2-pyridyl) -1,2,4-triazole) dimethylphenylphosphine, osmium (II) bis (4-tert-butylpyridyl) -1,2,4-triazoleate) Dimethylphenylphosphine, bis [2- (4-n-hexylphenyl) quinoline Iridium (III), tris [2- (4-n-hexylphenyl) quinoline] iridium (III) Phenylquinoline) (2- (3-methylphenyl) pyridinate Iridium (III), bis (2- (9,9-diethyl- (Acetylacetonate) iridium (III), bis (2-phenylpyridine) (3- (pyridin-2-yl) -2H- chromen- 2-phenylquinoline) (2,2,6, (III), bis (phenylisoquinoline) (2,2,6,6-tetramethylheptane-3,5-dionate) iridium (III) (E) -2- (2-t-butyl-6- (2-tert-butylphenyl) - (2,6,6-trimethyl-2,4,5,6-tetrahydro-1H-pyrrolo [3,2,1-ij] quinolin- (Methylene diphenylphosphine) ruthenium, bis [(4-n-hexylphenyl) isoquinolinone, bis (3-trifluoromethyl-5- (Acetylacetonate) iridium (III), platinum (II) octaethyloporphine, bis (2-methyldibenzo [f, h] quinoxaline) 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- 1,7-diphenyl-1,10-phenanthroline, bis (2-methyl-8-quinolinolato) -4- (phenylphenolato) aluminum, 1,3- Bis [2- (2,2'-bipyridin-6-yl) -1,3,4-oxadiazo 5-yl] benzene, 6,6'-bis [5- ) -1,3,4-oxadiazo-2-yl] -2,2'-bipyridine, 3- (4-biphenyl) -4-phenyl- (Naphthalene-2-yl) -4,7-diazabicyclo < / RTI > 1,10-phenanthroline, 2,7-bis [2- (2,2'-bipyridin-6-yl) -1,3,4-oxadiazo-5-yl] -9 , 9-dimethylfluorene, 1,3-bis [2- (4-t-butylphenyl) -1,3,4-oxadiazo-5-yl] benzene, tris 1-methyl-2- (4- (naphthalen-2-yl) phenyl) -1H-imidazo [4,5f] [1,10 ] Phenanthroline, 2- (naphthalene-2-yl) -4,7-diphenyl-1,10-phenanthroline, phenyl-diphenylenphosphine oxide, 3,3 ', 5,5'-tetra 3-yl] benzene, 4,4'-bis (4,6-dihydroxyphenyl) (Diphenyl-1,3,5-triazin-2-yl) biphenyl, 1,3-bis [3,5- (pyrene-1-yl) pyridine, and the like can be given as examples of the diazonium salt.

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 (CsF), strontium fluoride (SrF ₂ ), molybdenum trioxide (MoO ₃ ), aluminum, 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.

Examples of the material for forming the electron block layer include tris (phenylpyrazole) iridium and the like.

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

Specifically, the hole transporting varnish of the present invention is coated on 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 electrode is deposited to form the PLED Device.

As the anode and cathode materials to be used, the same materials as in the production of the OLED 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 is added, A method of forming a film by coating each film after the coating, and the like.

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'- -Butylphenyl} -1,4-diaminophenylene), poly [N, N'-bis (4-butylphenyl) -N, N'-bis (4,9 '- (N- (p-butylphenyl)) diphenylamine)], and the like can be given as examples of the poly [(9,9-dioctylfluorenyl-2,7-diyl) have.

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 coating 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.

Further, not only the charge-transporting thin film obtained from the above-described charge-transporting varnish but also the vapor-deposited film obtained from the thiophene derivative of the present invention is excellent in charge transportability, so that the charge-transporting thin film obtained by the vapor deposition method may be used depending on the use.

Example

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

(1) Liquid chromatography: Agilent 1260 Infinity binary LC system manufactured by Agilent Technologies

(2) NMR: JNM-ECP300 FT NMR system manufactured by Nippon Denshi K.K.

(3) Substrate cleaning: Chosho Sangyo Co., Ltd., substrate cleaning apparatus (reduced pressure plasma system)

(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 Surfcoda ET-4000

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

(7) Measurement of luminance etc. of EL element: I-V-L measurement system

(8) Measurement of lifetime of EL device: Organic EL luminance lifetime evaluation system PEL-105S

[1] Synthesis of Compound

[Synthesis Example 1]

3-methoxy-2- (tri-n-butylstannyl) thiophene (9) was synthesized on the basis of the following reaction formula.

5.01 g of 3-methoxythiophene (8) was placed in a flask, and nitrogen replacement was carried out. Thereto, 100 mL of diisopropyl ether was added and the mixture was cooled to 0 占 폚, and 29.5 mL of a hexane solution of n-butyllithium (concentration: 1.64M) was added dropwise thereto. After the dropwise addition, the mixture was stirred for 30 minutes while maintaining the temperature at 0 ° C, 14.5 mL of tri-n-butylstannyl chloride was added dropwise, and the mixture was further stirred for 3 hours while maintaining the temperature at 0 ° C.

After stirring, the solvent was distilled off under reduced pressure, and n-hexane was added to the obtained residue. The resulting insoluble matter was separated by filtration, and the solvent was distilled off under reduced pressure and dried to obtain 3-methoxy-2- Tri-n-butylstannyl) thiophene.

This mixture was used for the reaction with compound (10) in the next step without further purification. Further, it was confirmed by using ¹ H-NMR and liquid chromatography that the content of 3-methoxy-2- (tri-n-butylstanyl) thiophene in the mixture was 90.46%.

[Example 1]

The thiophene derivative (11) was synthesized by the following method.

In a flask, 0.5 g of 2,3,4,5-tetrabromothiophene (10) (manufactured by Tokyo Kasei Kogyo K.K.) and 3 g of 3-methoxy-2- (tri-n-butylstannyl) thiophene (4.8 equivalents, purity 90.46%) of compound (9) were placed in a reaction vessel and subjected to nitrogen substitution. Thereto, 10 ml of xylene and 0.073 g (5 mol%) of Pd (PPh ₃ ) ₄ were added and stirred for 23 hours under heating and refluxing conditions. After completion of the stirring, the reaction solution was cooled to room temperature.

After chloroform and ion-exchange water were added to the cooled reaction solution to carry out liquid separation treatment, the obtained organic layer was washed twice with ion-exchanged water, and then the organic layer after the washing was dried with sodium sulfate and then the solvent was distilled off Removed. Then, n-hexane was added to the obtained residue, the slurry was washed, and the filtrate was collected by filtration.

Thereafter, the filtrate and 5 mL of toluene were added to the flask, and the mixture was stirred under heating and refluxing conditions to confirm that the filtrate was dissolved, and then the solution was allowed to cool to room temperature.

After allowing to cool, the precipitate was recovered by filtration and dried well to obtain thiophene derivative (11) (yield: 0.40 g, yield: 60%). The measurement results of ¹ H-NMR are shown below.

[2] preparation of charge transport varnish

[Example 2]

0.052 g of thiophene derivative (11) and 0.258 g of tungstic acid (manufactured by Kanto Kagaku Co., Ltd.) were dissolved in 3.0 g of 1,3-dimethyl-2-imidazolidinone under a nitrogen atmosphere. To the obtained solution, 0.009 g of pentafluorophenyltriethoxysilane was added and stirred, and then 5.0 g of diethylene glycol dimethyl ether and 2 g of butanediol were added and stirred to prepare a charge transporting varnish did.

[3] Manufacturing and Characterization of Organic EL Device

[Example 3]

The varnish obtained in Example 2 was applied to an ITO substrate using a spin coater, dried at 50 DEG C for 5 minutes, and fired at 230 DEG C for 10 minutes in an air atmosphere to form a uniform thin film of 30 nm on the ITO substrate did. As the ITO substrate, a glass substrate of 25 mm x 25 mm x 0.7 t in which indium tin oxide (ITO) was patterned on the surface with a film thickness of 150 nm was used and impurities on the surface were removed by an O ₂ plasma cleaning apparatus (150 W, 30 seconds) Removed.

Then, with respect to the ITO substrate to form a thin film, and α-NPD, Alq _3, and then depositing a thin film of lithium fluoride and aluminum using a vapor deposition device (degree of vacuum of 1.0 × 10 ^-5 Pa), an organic EL element was completed. At this time, the deposition rate was 0.2 nm / sec for α-NPD, Alq ₃ and aluminum, and 0.02 nm / sec for lithium fluoride, respectively, and the film thicknesses were 30 nm, 40 nm, 0.5 nm and 120 nm, respectively.

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 between the sealing substrates in a nitrogen atmosphere having an oxygen concentration of 2 ppm or less and a dew point of -85 占 폚 or less and the sealing substrate was bonded by an adhesive (XNR5516Z-B1, manufactured by Nagase Chemtech Co., Ltd.). At this time, a repairing agent (HD-071010W-40, manufactured by Dainichick) was put together with the organic EL element in the sealing substrate. The bonded sealing substrate was irradiated with UV light (wavelength: 365 nm, irradiation amount: 6,000 mJ / cm ² ) and annealed at 80 캜 for 1 hour to cure the adhesive.

[Comparative Example 1]

A device was fabricated in the same manner as in Example 3 except that PEDOT / PSS (AI4083, manufactured by HCS Tarco Co., Ltd.) was used instead of the varnish obtained in Example 2, and the resultant was fired at 150 ° C for 30 minutes instead of firing at 230 ° C for 10 minutes did.

Measurement of current density and luminance at a driving voltage of 5 V and durability test of the fabricated device were performed. The measurement results and the half-life of the luminance (initial luminance of 5,000 cd / m ² ) are shown in Table 1.

Current density
(mA / cm ² ) Luminance
(cd / m ² ) Half-life
(time) Example 3 110 2,713 264 Comparative Example 1 116 3,367 10

As shown in Table 1, the organic EL device (Example 3) having the hole injection layer obtained from the varnish of the present invention had far superior durability as compared with the case of using PEDOT / PSS as a general charge transporting material (Comparative Example 1) .

Claims (12)

A thiophene derivative represented by the following formula (1).

(Wherein, R ¹ ~R ⁴ are, each independently optionally substituted, an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ¹ may carbon atoms which is optionally substituted by alkynyl, alkoxy group, alkenyloxy group, Z ¹ of 2 to 20 carbon atoms which may be substituted with Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ¹ of the 2 to 20 carbon atoms 20 alkynyl of acryloyloxy group, come alkylthio of 1 to 20 carbon atoms which may be substituted with Z ^1, Im coming alkenyl of 2 to 20 carbon atoms which may be substituted with Z ^1, carbon atoms which may be substituted with Z ¹ 2 to 20 the alkynyl Im come, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, hetero aryloxy group of 2 to 20 carbon atoms which may be substituted with Z ^2, carbon atoms which may be substituted with Z ² 6-20 aryl can be substituted with Cy import or Z ² Represents a heteroaryl Im come in Figure 2 to 20 carbon atoms which,
R ⁵ ~R ⁸ are, each independently, a hydrogen atom, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may C2-C20 alkynyl, alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, the carbon atoms that may be substituted with Z ¹ 2 to 20 An alkynyloxy group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkylthio group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkenylthio group of 2 to 20 carbon atoms which may be substituted with Z ¹ , alkynyl Im come, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ^2, of 2 to 20 carbon atoms which may be substituted with Z ² hetero aryloxy, substituted with Z ² of 6 to 20 carbon atoms which may An arylthio group or Z < ² > Or a heteroarylthio group having 2 to 20 carbon atoms,
When R ⁵ to R ⁸ are not hydrogen atoms, R ¹ and R ⁵ , R ² and R ⁶ , R ³ and R ⁷ and / or R ⁴ and R ⁸ may be bonded to each other to form a divalent group,
~R ⁹ R ¹² are, each independently, a hydrogen atom, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may C2-C20 alkynyl, alkenyloxy group of 2 to 20 carbon atoms which may be substituted with an alkoxy group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, the carbon atoms that may be substituted with Z ¹ 2 to 20 An alkynyloxy group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkylthio group of ¹ to 20 carbon atoms which may be substituted with Z ¹ , an alkenylthio group of 2 to 20 carbon atoms which may be substituted with Z ¹ , An alkynylthio group or an aryl group having 6 to 20 carbon atoms which may be substituted with Z < ² >
Z ¹ represents a halogen atom, an alkoxy group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, an alkynyloxy group having 2 to 20 carbon atoms, an alkylthio group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms An alkynylthio group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a heteroaryloxy group having 2 to 20 carbon atoms, an arylthio group having 6 to 20 carbon atoms, A heteroarylthio group having 1 to 20 carbon atoms,
Z ² represents a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, An alkylthio group having 1 to 20 carbon atoms, an alkenylthio group having 2 to 20 carbon atoms, an alkynylthio group having 2 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a heteroatom having 2 to 20 carbon atoms An arylthio group having 6 to 20 carbon atoms, or a heteroarylthio group having 2 to 20 carbon atoms. The method according to claim 1,
The R ¹ ~R ^4, each independently, an alkoxy group, an alkenyloxy group of 2 to 20 carbon atoms which may be substituted with Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, carbon atoms which may be substituted with Z ¹ alkynyl of 2 to 20-yloxy group, come alkylthio of 1 to 20 carbon atoms which may be substituted with Z ^1, Im coming alkenyl of 2 to 20 carbon atoms which may be substituted with Z ^1, carbon atoms which may be substituted with Z ¹ 2 An alkynylthio group of ² to 20 carbon atoms, an aryloxy group of 6 to 20 carbon atoms which may be substituted with Z ² , a heteroaryloxy group of 2 to 20 carbon atoms which may be substituted with Z ² , a carbon number of 6 An arylthio group having 1 to 20 carbon atoms or a heteroarylthio group having 2 to 20 carbon atoms which may be substituted with Z < ^{2 &} gt ;. 3. The method according to claim 1 or 2,
R ⁵ ~R ⁸ are, each independently, a hydrogen atom, is substituted with an alkenyl group, Z ¹ of 2 to 20 carbon atoms that may be substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may An alkynyl group having 2 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms which may be substituted with Z &^lt; 1 >. 4. The method according to any one of claims 1 to 3,
R ⁹ is ~R ^12, each independently, a hydrogen atom, is substituted with an alkenyl group of 2 to 20 carbon atoms or Z ¹ is optionally substituted with an alkyl group, Z ¹ of 1 to 20 carbon atoms which may be substituted with Z ^1, which may A thiophene derivative which is an alkynyl group having 2 to 20 carbon atoms. The method according to claim 1,
A process for producing a thiophene derivative, which comprises reacting a thiophene compound represented by the formula (2) and a trialkylstannylthiophene compound represented by the formula (3) to (6) in the presence of a catalyst.

(Wherein each Hal independently represents a halogen atom or a similar group, and R ^a independently represents an alkyl group having 1 to 20 carbon atoms, R ¹ to R ¹² are as defined above.) A charge-transporting material comprising the thiophene derivative according to any one of claims 1 to 4. A charge transporting varnish comprising the thiophene derivatives, dopants and organic solvents according to any one of claims 1 to 4. A charge-transporting thin film produced using the charge-transporting varnish according to claim 7. A charge transporting thin film comprising the thiophene derivative according to any one of claims 1 to 4. 9. An electronic device comprising at least one charge-transporting thin film according to claim 8 or 9. An organic electroluminescent device comprising at least one charge transporting thin film according to claim 8 or 9. 12. The method of claim 11,
Wherein the charge transporting thin film is a hole injecting layer or a hole transporting layer.