JP6503675B2 - Charge transporting varnish, charge transporting thin film and organic electroluminescent device - Google Patents

Description

  The present invention relates to a charge transporting varnish, a charge transporting thin film and an organic electroluminescent (hereinafter referred to as organic EL) device.

  For the organic EL element, a charge transporting thin film made of an organic compound is used as a light emitting layer or a charge injection layer. In particular, the hole injection layer is responsible for charge transfer between the anode and the hole transport layer or the light emitting layer, and plays an important function to achieve low voltage drive and high luminance of the organic EL element.

  The formation method of the hole injection layer is roughly divided into a dry process represented by a vapor deposition method and a wet process represented by a spin coating method, and comparing these processes, the wet process has a larger area and flatness. Thin films can be produced efficiently. Therefore, as the area of the organic EL display is increased, a hole injection layer that can be formed by a wet process is desired at present.

  In view of such circumstances, the present inventors are applicable to various wet processes and charge transportability giving a thin film which can realize excellent EL element characteristics when applied to a hole injection layer of an organic EL element. Compounds having good solubility in materials and organic solvents used therefor have been developed (see, for example, Patent Documents 1 to 4).

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

  The present invention is to provide a charge transportable varnish which gives a thin film which can realize excellent properties when applied to a hole injection layer of an organic EL element, like the technology of the above-mentioned patent documents developed so far. To aim.

  As a result of intensive studies to achieve the above object, the present inventors have found that a thin film obtained from a varnish comprising a charge transportable substance comprising a predetermined thiophene derivative, a dopant, and an organic solvent is highly charge transportable. In the case where the thin film is applied to a hole injection layer of an organic EL device, the present invention has been accomplished, as a result of the finding that excellent luminance characteristics and excellent durability can be realized.

（式中、Ｒ¹〜Ｒ²¹は、それぞれ独立に、水素原子、ハロゲン原子、ニトロ基、シアノ基、アルデヒド基、ヒドロキシ基、チオール基、カルボン酸基、Ｚ¹で置換されていてもよい炭素数１〜２０のアルキル基、Ｚ¹で置換されていてもよい炭素数２〜２０のアルケニル基、Ｚ¹で置換されていてもよい炭素数２〜２０のアルキニル基、Ｚ²で置換されていてもよい炭素数６〜２０のアリール基、−Ｃ(Ｏ)Ｙ¹基、−ＯＹ²基、−ＳＹ³基、−Ｃ(Ｏ)ＯＹ⁴基、−ＯＣ(Ｏ)Ｙ⁵基、−Ｃ(Ｏ)ＮＨＹ⁶基又は−Ｃ(Ｏ)ＮＹ⁷Ｙ⁸基を表し、
Ｙ¹〜Ｙ⁸は、それぞれ独立に、Ｚ¹で置換されていてもよい炭素数１〜２０のアルキル基、Ｚ¹で置換されていてもよい炭素数２〜２０のアルケニル基、Ｚ¹で置換されていてもよい炭素数２〜２０のアルキニル基又はＺ²で置換されていてもよい炭素数６〜２０のアリール基を表し、
Ｚ¹は、ハロゲン原子、ニトロ基、シアノ基、アルデヒド基、ヒドロキシ基、チオール基、スルホン酸基、カルボン酸基又はＺ³で置換されていてもよい炭素数６〜２０のアリール基を表し、
Ｚ²は、ハロゲン原子、ニトロ基、シアノ基、アルデヒド基、ヒドロキシ基、チオール基、スルホン酸基、カルボン酸基、Ｚ³で置換されていてもよい炭素数１〜２０のアルキル基、Ｚ³で置換されていてもよい炭素数２〜２０のアルケニル基又はＺ³で置換されていてもよい炭素数２〜２０のアルキニル基を表し、
Ｚ³は、ハロゲン原子、ニトロ基、シアノ基、アルデヒド基、ヒドロキシ基、チオール基、スルホン酸基又はカルボン酸基を表し、
ｎ¹〜ｎ³は、それぞれ独立に２〜１０の整数を表す。）

（式中、Ｒ ¹⁰¹ 〜Ｒ ¹⁰⁴ は、それぞれ独立に、水素原子又はフッ素原子を表すが、少なくとも１つはフッ素原子である。）
２．式（１）で表されるチオフェン誘導体からなる電荷輸送性物質と、ヘテロポリ酸を含むドーパントと、有機溶媒と、有機シラン化合物とを含み、上記有機シラン化合物が、ジアルコキシシラン化合物、トリアルコキシシラン化合物又はテトラアルコキシシラン化合物を含む１の電荷輸送性ワニス。
３．上記Ｒ ¹⁰¹ 〜Ｒ ¹⁰⁴ が、フッ素原子である１の電荷輸送性ワニス。
４．上記有機シラン化合物が、ジアルコキシシラン又はトリアルコキシシランを含む１〜３のいずれかの電荷輸送性ワニス。
５．１〜４のいずれかの電荷輸送性ワニスを用いて作製される電荷輸送性薄膜。
６．５の電荷輸送性薄膜を有する有機エレクトロルミネッセンス素子。
７．上記電荷輸送性薄膜が、正孔注入層又は正孔輸送層である６の有機エレクトロルミネッセンス素子。
８．１〜４のいずれかの電荷輸送性ワニスを基材上に塗布して焼成することを特徴とする電荷輸送性薄膜の製造方法。
９．５の電荷輸送性薄膜を用いることを特徴とする有機エレクトロルミネッセンス素子の製造方法。
１０．１〜４のいずれかの電荷輸送性ワニスを基材上に塗布する工程と、２００℃未満の温度で焼成する工程と、を含む電荷輸送性薄膜の製造方法。
That is, the present invention provides the following charge transporting varnish, charge transporting thin film and organic EL device.
1. It is selected from a charge transportable substance comprising a thiophene derivative represented by the formula (1), a dopant containing a heteropoly acid , an organic solvent, an organic silane compound and a tetracyanoquinodimethane compound represented by the following formula (6) at least one and only containing said organic silane compound is a dialkoxy silane compound, a charge-transporting varnish which comprises a trialkoxysilane compound or tetraalkoxysilane compound.

(Wherein, R ^{1 to} R ²¹ each independently represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a carboxylic acid group, carbon optionally substituted by Z ¹ C 1 -C 20 alkyl group, an alkenyl group which may C2-20 optionally substituted by Z ^1, alkynyl group optionally having 2 to 20 carbon atoms optionally substituted by Z ^1, substituted by Z ² Aryl group having 6 to 20 carbon atoms, -C (O) Y ¹ group, -OY ² group, -SY ³ group, -C (O) OY ⁴ group, -OC (O) Y ⁵ group,- Represents a C (O) NHY ⁶ group or a -C (O) NY ⁷ Y ⁸ group,
Y ¹ to Y ⁸ each independently represent an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^1, alkenyl group which may C2-20 optionally substituted by Z ^1, in Z ¹ Represents a C2-C20 alkynyl group which may be substituted or a C6-C20 aryl group which may be substituted by Z ² ,
Z ¹ represents a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a sulfonic acid group, a carboxylic acid group, or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ³ ;
Z ² is a halogen atom, a nitro group, a cyano group, an aldehyde group, hydroxy group, thiol group, sulfonic acid group, a carboxylic acid group, an alkyl group of Z ³ carbon atoms which may be substituted with 1 to 20, Z ³ And an alkenyl group of 2 to 20 carbon atoms which may be substituted or an alkynyl group of 2 to 20 carbon atoms which may be substituted by Z ³ ;
Z ³ represents a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a sulfonic acid group or a carboxylic acid group,
n ^{1 to} n ³ each independently represent an integer of 2 to 10. )

(Wherein, R ^{101 to} R ¹⁰⁴ each independently represent a hydrogen atom or a fluorine atom, but at least one is a fluorine atom)
2. A charge transportable substance comprising a thiophene derivative represented by the formula (1), a dopant containing a heteropolyacid, an organic solvent, and an organic silane compound, wherein the organic silane compound is a dialkoxysilane compound, a trialkoxysilane A charge transporting varnish according to 1 which comprises a compound or a tetraalkoxysilane compound.
3. The charge transporting varnish according to 1, wherein each of R ^{101 to} R ¹⁰⁴ is a fluorine atom.
4. The charge transporting varnish according to any one of 1 to 3, wherein the organosilane compound comprises dialkoxysilane or trialkoxysilane.
The charge transportable thin film produced using the charge transportable varnish in any one of 5.1-4.
The organic electroluminescent element which has a charge transportable thin film of 6.5.
7. 7. The organic electroluminescent device according to 6, wherein the charge transporting thin film is a hole injection layer or a hole transport layer.
8. A method for producing a charge transporting thin film, comprising applying the charge transporting varnish of any one of 1 to 4 onto a substrate and baking it.
9. 5. A method of manufacturing an organic electroluminescent device, comprising using the charge transporting thin film of 5 .
10. A method for producing a charge transporting thin film, comprising the steps of: applying the charge transporting varnish of any one of 1 to 4 onto a substrate; and baking it at a temperature less than 200 ° C.

The thiophene derivative used in the present invention is easily soluble in an organic solvent, and it can be dissolved in an organic solvent together with a dopant to easily prepare a charge transporting varnish.
The thin film produced from the charge-transporting varnish of the present invention exhibits high charge-transporting properties, and thus can be suitably used as a thin film for an electronic device including an organic EL element. In particular, by applying this thin film to the hole injection layer of the organic EL element, an organic EL element excellent in luminance characteristics and durability can be obtained.
Furthermore, the charge transporting varnish of the present invention can be fired at a lower temperature than conventional ones by containing an organosilane compound or a tetracyanoquinodimethane compound, and even in such a case, the thin film produced is highly flat and high. It has charge transportability.
Further, the charge transporting varnish of the present invention can reproducibly produce a thin film having excellent charge transporting properties even when various wet processes capable of forming a film on a large area, such as spin coating method and slit coating method, are used. It can sufficiently cope with the recent progress in the field of organic EL elements.
The thin film obtained from the charge transporting varnish of the present invention can also be used as an antistatic film, an anode buffer layer of an organic thin film solar cell, or the like.

[Charge transportable substance]
The charge transporting varnish of the present invention comprises a charge transporting substance comprising a thiophene derivative represented by the following formula (1).

  In the present invention, charge transportability is synonymous with conductivity, and is synonymous with hole transportability. The charge transporting substance may be one having a charge transporting property itself, or may be one having a charge transporting property when used together with an electron accepting substance. The charge transporting varnish may itself be charge transporting, and the solid film obtained thereby may be charge transporting.

Each of R ^{1 to} R ²¹ independently represents a hydrogen atom, a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a carboxylic acid group, a carbon number of 1 to 20 optionally substituted by Z ¹ alkyl group, Z ¹ in an optionally substituted alkenyl group having 2 to 20 carbon atoms, an alkynyl group which may C2-20 optionally substituted by Z ^1, the carbon may be substituted with Z ² Aryl groups of 6 to 20, —C (O) Y ¹ group, —OY ² group, —SY ³ group, —C (O) OY ⁴ group, —OC (O) Y ⁵ group, —C (O) group Represents a NHY ⁶ group or a -C (O) NY ⁷ Y ⁸ group.

Y ¹ to Y ⁸ each independently represent an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^1, alkenyl group which may C2-20 optionally substituted by Z ^1, in Z ¹ This represents an alkynyl group having 2 to 20 carbon atoms which may be substituted, or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ² .

Z ¹ represents a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a sulfonic acid group, a carboxylic acid group, or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ³ .

Z ² is a halogen atom, a nitro group, a cyano group, an aldehyde group, hydroxy group, thiol group, sulfonic acid group, a carboxylic acid group, an alkyl group of Z ³ carbon atoms which may be substituted with 1 to 20, Z ³ And an alkenyl group of 2 to 20 carbon atoms which may be substituted or an alkynyl group of 2 to 20 carbon atoms which may be substituted by Z ³ .

Z ³ represents a halogen atom, a nitro group, a cyano group, an aldehyde group, hydroxy group, thiol group, a sulfonic acid group or carboxylic acid group.

n ^{1 to} n ³ each independently represent an integer of 2 to 10.

  As a halogen atom, a fluorine, chlorine, a bromine, an iodine atom etc. are mentioned.

  The alkyl group having 1 to 20 carbon atoms may be linear, branched, or cyclic, and examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and s. -C1-C20 linear or branched, such as -butyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl and n-decyl Alkyl group; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, bicyclobutyl group, bicyclopentyl group, bicyclohexyl group, bicycloheptyl group, bicyclooctyl group And a cyclic alkyl group having 3 to 20 carbon atoms such as bicyclononyl group and bicyclodecyl group.

  Specific examples of the alkenyl group having 2 to 20 carbon atoms include ethenyl group, n-1-propenyl group, n-2-propenyl group, 1-methylethenyl group, n-1-butenyl group, n-2-butenyl group, n-3-butenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, 1-methyl-1-propenyl group, 1-methyl-2-propenyl group, n- 1-pentenyl group, n-1-decenyl group, n-1-eicosenyl group etc. are mentioned.

  Specific examples of the alkynyl group having 2 to 20 carbon atoms include ethynyl group, n-1-propynyl group, n-2-propynyl group, n-1-butynyl group, n-2-butynyl group, n-3-butynyl group Group, 1-methyl-2-propynyl group, n-1-pentynyl group, n-2-pentynyl group, n-3-pentynyl group, n-4-pentynyl group, 1-methyl-n-butynyl group, 2- Methyl-n-butynyl group, 3-methyl-n-butynyl group, 1,1-dimethyl-n-propynyl group, n-1-hexynyl group, n-1-decynyl group, n-1-pentadecynyl group, n- 1-eicosinyl group etc. are mentioned.

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

As R ^{1 to} R ²¹ , a hydrogen atom or an alkyl group having 1 to 20 carbon atoms which may be substituted with Z ¹ is preferable, and a hydrogen atom is optimal.

When R ^{1 to} R ²¹ and Y ^{1 to} Y ⁸ are an alkyl group, an alkenyl group, an alkynyl group or an aryl group, as Z ¹ , a carbon atom having 6 to 6 carbon atoms which may be substituted by a halogen atom or Z ³ 20 aryl groups are preferred, and more preferred is a phenyl group which may be substituted by Z ³ and optimally absent (ie unsubstituted).
The Z ^2, a halogen atom or an alkyl group Z ³ carbon atoms which may be substituted with 1 to 20, more preferably an alkyl group having 1 to 10 carbon atoms optionally substituted by Z ^3, Z more preferably more alkyl group which may C1-8 be substituted with ^3, more preferably an alkyl group having carbon atoms which may be have 1-6 substituted with Z ^3, that does not exist (i.e., unsubstituted ) Is the best.
Z ³ is preferably a halogen atom, more preferably fluorine, and most preferably absent (ie, unsubstituted).

  Hereinafter, although the specific example of the thiophene derivative represented by Formula (1) is given, it is not limited to these.

[Method for producing thiophene derivative]
The thiophene derivative used in the present invention can be synthesized, for example, according to the method described in Tetrahedron Letters, 2010, 51 (50), pp. 6673-6676, JP-A No. 2003-167972, etc. It is not limited.

  Specifically, for example, triphenylamine or a derivative thereof and thiophene or a derivative thereof as a starting material, Kumada coupling, Akita-Kosugi-Stil coupling, Negishi coupling, Suzuki-Miyaura coupling, Hayama coupling, etc. It can be synthesized by coupling reaction.

（式中、Ｒ¹〜Ｒ²¹及びｎ¹〜ｎ³は上記と同じ。） As one example, triphenylamine represented by formula (2) or a derivative thereof is halogenated or stanylated, etc., and represented by formulas (3) to (5) to cause cross-coupling reaction with this. The thiophene derivative may be stanylated or the like or halogenated and subjected to a coupling reaction.

(Wherein, R ^{1 to} R ²¹ and n ^{1 to} n ³ are as defined above)

  In this case, the preparation ratio of the thiophene or its derivative represented by the formulas (3) to (5) is generally 0.5 to 1 to the triphenylamine or its derivative represented by the formula (2). Although it is about 5 equivalent, about 0.9 to 1.3 equivalent is suitable.

  In addition, as a compound represented by Formula (2)-(5), a commercial item may be used and you may synthesize | combine by a well-known method.

[Dopant]
The charge transporting varnish of the present invention contains a dopant. The dopant is not particularly limited, and either an organic dopant or an inorganic dopant can be used.

  Among them, in the most preferred embodiment, the charge transporting varnish of the present invention contains a heteropoly acid as a dopant, and therefore, from a transparent electrode represented by indium tin oxide (ITO) and indium zinc oxide (IZO). It is possible to obtain not only high hole accepting ability but also a thin film excellent in charge transportability showing high hole accepting ability from a metal anode represented by aluminum.

  Heteropoly acids have a structure in which the hetero atom is located at the center of the molecule, represented by the chemical structure of the Keggin type represented by the formula (A1) or the Dawson type represented by the formula (A2). V) A polyacid formed by condensation of an isopolyacid which is an oxo acid such as molybdenum (Mo) or tungsten (W) and an oxo acid of a different element. Such oxo acids of different elements mainly include oxo acids of silicon (Si), phosphorus (P) and arsenic (As).

  Specific examples of heteropoly acids include phosphomolybdic acid, silicomolybdic acid, phosphotungstic acid, silicotungstic acid, lintungstomolybdic acid and the like. These may be used alone or in combination of two or more. The heteropoly acid used in the present invention is commercially available, and can be synthesized by a known method.

  In particular, when the dopant consists of one type of heteropolyacid, the one type of heteropolyacid is preferably phosphotungstic acid or phosphomolybdic acid, and more preferably phosphotungstic acid. When the dopant consists of two or more heteropoly acids, at least one of the two or more hetero poly acids is preferably phosphotungstic acid or phosphomolybdic acid, and more preferably phosphotungstic acid.

  In addition, heteropoly acids are obtained as commercial products even if the number of elements is large or small from the structure represented by the general formula in quantitative analysis such as elemental analysis, or a known synthesis method It can be used in the present invention as long as it is appropriately synthesized according to

That is, for example, phosphotungstic acid is generally represented by the chemical formula H ₃ (PW ₁₂ O ₄₀ ) .nH ₂ O, and phosphomolybdic acid is represented by the chemical formula H ₃ (PMo ₁₂ O ₄₀ ) .nH ₂ O, respectively. In quantitative analysis, even if the number of P (phosphorus), O (oxygen) or W (tungsten) or Mo (molybdenum) in this formula is large or small, it is obtained as a commercial product, or It can be used in the present invention as long as it is appropriately synthesized according to known synthetic methods. In this case, the mass of the heteropoly acid defined in the present invention is not the mass (phosphotungstic acid content) of pure phosphotungstic acid in a synthetic or commercial product, but a commercially available form and known synthesis In the form which can be isolated by the method, it means the total mass in the state including hydration water and other impurities.

  The heteropoly acid contained in the charge transporting varnish of the present invention can have a mass ratio of about 1.0 to 70.0 with respect to the charge transporting substance 1, but is preferably 2.0 to 60.0. The degree is more preferably about 2.5 to 55.0, and still more preferably about 2.5 to 25.0.

[Organic solvent]
As the organic solvent used in preparing the charge transporting varnish, a high solubility solvent which can dissolve the charge transporting substance and the dopant well can be used.
As such a high solubility solvent, for example, an organic solvent such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like may be used. it can. These solvents may be used alone or in combination of two or more, and the amount thereof may be 5 to 100% by mass with respect to the entire solvent used for the varnish.
The charge transporting substance and the dopant are preferably completely dissolved in the solvent.

Further, in the present invention, the varnish has 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. at normal pressure (atmospheric pressure). By including at least one high-viscosity organic solvent, adjustment of the viscosity of the varnish becomes easy, and as a result, it becomes possible to prepare a varnish according to the application method to be used, giving a thin film with high flatness with good reproducibility.
The high viscosity organic solvent is not particularly limited. For example, cyclohexanol, ethylene glycol, ethylene glycol diglycidyl ether, 1,3-octylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, propylene glycol, hexylene glycol and the like. These solvents may be used alone or in combination of two or more.
It is preferable that the addition ratio of the high viscosity organic solvent with respect to the whole solvent used for the varnish of this invention is in the range which a solid does not precipitate, and as long as a solid does not precipitate, 5-80 mass% is preferable.

Furthermore, for the purpose of improving the wettability to the substrate, adjusting the surface tension of the solvent, adjusting the polarity, adjusting the boiling point, and the like, the other solvent is preferably 1 to 90% by mass, preferably the entire solvent used in the varnish. It can also be mixed in a proportion of 1 to 50% by mass.
As such solvent, for example, ethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol Monoethyl ether, diacetone alcohol, γ-butyrolactone, ethyl lactate, n-hexyl acetate, diethylene glycol monomethyl ether and the like can be mentioned, but it is not limited thereto. These solvents may be used alone or in combination of two or more.

Although the viscosity of the varnish of this invention is suitably set according to the thickness etc. and solid content concentration of the thin film to produce, it is 1-50 mPa * s normally at 25 degreeC.
The solid content concentration of the charge transporting varnish in the present invention is appropriately set in consideration of the viscosity and surface tension of the varnish, the thickness of the thin film to be produced, etc. It is about 0% by mass, and preferably about 0.5 to 5.0% by mass, and more preferably about 1.0 to 3.0% by mass, in consideration of improving the coatability of the varnish.

[Organosilane compound]
The charge transporting varnish of the present invention preferably contains an organic silane compound. Examples of the organic silane compound include dialkoxysilane compounds, trialkoxysilane compounds and tetraalkoxysilane compounds. These may be used alone or in combination of two or more.

  In particular, the organosilane compound preferably contains one selected from dialkoxysilane compounds and trialkoxysilane compounds, and more preferably contains a trialkoxysilane compound.

Examples of the dialkoxysilane compound, the trialkoxysilane compound and the tetraalkoxysilane compound include those represented by formulas (B1) to (B3).
SiR ' ₂ (OR) ₂ (B1)
SiR '(OR) ₃ (B2)
Si (OR) ₄ (B3)

In the formula, R is a substituted each independently, Z ¹⁰¹ with an optionally substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group which may C2-20 optionally substituted by Z ^101, with Z ¹⁰¹ is an alkynyl group having a carbon number of 2 to 20 even if, heteroaryl aryl or Z ¹⁰² good 2 to 20 carbon atoms optionally substituted by from 6 to 20 carbon atoms which may be substituted with Z ¹⁰² Represents R 'is independently, Z ¹⁰³ alkyl group carbon atoms which may be have 1 to 20 substituted by an alkenyl group which may C2-20 optionally substituted by Z ^103, substituted by Z ¹⁰³ an alkynyl group having 2 to 20 carbon atoms also represents a heteroaryl group the aryl group or Z ¹⁰⁴ good 2 to 20 carbon atoms optionally substituted by from 6 to 20 carbon atoms which may be substituted with Z ¹⁰⁴ .

Z ¹⁰¹ represents a halogen atom, the heteroaryl group of the aryl group or Z ¹⁰⁵ good 2 to 20 carbon atoms optionally substituted by from 6 to 20 carbon atoms which may be substituted with Z ^105.
Z ¹⁰² is a halogen atom, optionally substituted alkenyl group, or Z ¹⁰⁵ of is an alkyl group having 1 to 20 carbon atoms also be good 2-20 carbon atoms substituted with Z ¹⁰⁵ substituted with Z ¹⁰⁵ It also represents an alkynyl group having 2 to 20 carbon atoms.

Z ¹⁰³ is a halogen atom, Z ¹⁰⁵ with an optionally substituted aryl group having 6 to 20 carbon atoms, a heteroaryl group which may C2-20 optionally substituted by Z ^105, epoxycyclohexyl group, a glycidoxy group represents a methacryloxy group, an acryloxy group, a ureido group (-NHCONH _2), thiol group, isocyanate group (-NCO), amino group, -NHY ¹⁰¹ group or -NY ¹⁰² Y ¹⁰³ groups.
Z ¹⁰⁴ is a halogen atom, Z ¹⁰⁵ alkyl group carbon atoms which may be have 1 to 20 substituted by an alkenyl group which may C2-20 optionally substituted by Z ^105, be substituted with Z ¹⁰⁵ Alkynyl group having 2 to 20 carbon atoms, epoxycyclohexyl group, glycidoxy group, methacryloxy group, acryloxy group, ureido group (-NHCONH ₂ ), thiol group, isocyanate group (-NCO), amino group, -NHY ¹⁰¹ group or -Represents a NY ¹⁰² Y ¹⁰³ group.

Y ¹⁰¹ to Y ¹⁰³ each independently represent an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^105, alkenyl group which may C2-20 optionally substituted by Z ^105, with Z ¹⁰⁵ an optionally substituted alkynyl group having 2 to 20 carbon atoms, heteroaryl aryl or Z ¹⁰⁵ good 2 to 20 carbon atoms optionally substituted by from 6 to 20 carbon atoms which may be substituted with Z ¹⁰⁵ Represents a group.
Z ¹⁰⁵ represents a halogen atom, an amino group, a nitro group, a cyano group or a thiol group.

  As a halogen atom, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C2-C20 alkynyl group and a C6-C20 aryl group in the formulas (B1) to (B3), The same as above can be mentioned.

The R, which may be substituted with an alkyl group, an alkenyl group, or Z ¹⁰² good 2 to 20 carbon atoms optionally substituted by Z ¹⁰¹ of carbon atoms which may be have 1-20 substituted with Z ¹⁰¹ carbon preferably an aryl group having 6 to 20, substituted with an alkyl group, an alkenyl group, or Z ¹⁰² 2-6 carbon atoms which may be substituted with Z ¹⁰¹ of carbon atoms which may be have 1-6 substituted with Z ¹⁰¹ more preferably a phenyl group which is, more preferably more even a phenyl group substituted with an alkyl group or Z ¹⁰² of 1 to 4 carbon atoms which may be substituted with Z ^101, is substituted with Z ¹⁰¹ More preferably, they may be methyl or ethyl.

As R ′, an alkyl group having 1 to 20 carbon atoms which may be substituted with Z ¹⁰³ or an aryl group having 6 to 20 carbons which may be substituted with Z ¹⁰⁴ is preferable, and R ′ is substituted with Z ¹⁰³ An alkyl group of 1 to 10 carbon atoms which may be substituted or an aryl group of 6 to 14 carbon atoms which may be substituted by Z ¹⁰⁴ is more preferable, and an alkyl of 1 to 6 carbon atoms which may be substituted by Z ¹⁰³ Still more preferably, the aryl group having 6 to 10 carbon atoms which may be substituted with a group or Z ¹⁰⁴ , and even if substituted with an alkyl group having 1 to 4 carbon atoms which may be substituted with Z ¹⁰³ or Z ¹⁰⁴ More preferred are phenyl groups.

  The plurality of R's may be all the same or different, and the plurality of R's may be all the same or different.

As Z ¹⁰¹ , a halogen atom or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ¹⁰⁵ is preferable, and a fluorine atom or a phenyl group which may be substituted with Z ¹⁰⁵ is more preferable, and is absent ( That is, non-substitution is optimal.

As the Z ^102, a halogen atom or Z is preferably an alkyl group which may having 6 to 20 carbon atoms optionally substituted by ^105, a fluorine atom or Z ¹⁰⁵ of carbon atoms which may be have 1 to 10 substituted by an alkyl group Is more preferred, and absent (i.e., unsubstituted) is optimal.

On the other hand, the Z ^103, a halogen atom, Z ¹⁰⁵ phenyl group which may be substituted by, may furanyl group optionally substituted by Z ^105, epoxycyclohexyl group, a glycidoxy group, a methacryloxy group, an acryloxy group, a ureido group, A thiol group, an isocyanate group, an amino group, a phenylamino group ^optionally substituted by Z ¹⁰⁵ , or a diphenylamino group optionally substituted by Z ¹⁰⁴ is preferable, a halogen atom is more preferable, and a fluorine atom or absence thereof ( That is, unsubstituted) is even more preferable.

As the Z ^104, a halogen atom, Z ¹⁰⁵ carbon atoms which may be substituted with 1 to 20 alkyl group, which may be furanyl substituted with Z ^105, epoxycyclohexyl group, a glycidoxy group, a methacryloxy group, An acryloxy group, a ureido group, a thiol group, an isocyanate group, an amino group, a phenylamino group ^optionally substituted by Z ¹⁰⁵ , or a diphenylamino group optionally substituted by Z ¹⁰⁵ is preferable, a halogen atom is more preferable, and fluorine is preferable. Even more preferred are atoms or absence (ie, unsubstituted).

And, as Z ¹⁰⁵ , a halogen atom is preferable, and a fluorine atom or absence (that is, being unsubstituted) is more preferable.

Hereinafter, although the specific example of the organic silane compound which can be used by this invention is given, it is not limited to these.
Specific examples of the dialkoxysilane compound include dimethyldimethoxysilane, dimethyldiethoxysilane, methylethyldimethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, methylpropyldimethoxysilane, methylpropyldiethoxysilane, diisopropyldimethoxysilane, phenylmethylsilane Dimethoxysilane, vinylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 3-methacryloxy Propylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-aminopropylmethyone Diethoxy silane, N- (2- aminoethyl) aminopropyl methyl dimethoxy silane, 3,3,3-trifluoropropyl methyl dimethoxy silane, and the like.

  Specific examples of trialkoxysilane compounds include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, Pentyltrimethoxysilane, pentyltriethoxysilane, heptyltrimethoxysilane, heptyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxy Silane, octadecyltrimethoxysilane, octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, biphenyl Trimethoxysilane, vinyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-methacryloxypropyl Trimethoxysilane, 3-methacryloxypropyltriethoxysilane, triethoxy (4- (trifluoromethyl) phenyl) silane, dodecyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, (triethoxysilyl) cyclohexane Perfluorooctylethyltriethoxysilane, triethoxyfluorosilane, tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane, pentafluorophenyltrimethoxysilane, pentafluro Orophenyltriethoxysilane, 3- (heptafluoroisopropoxy) propyltriethoxysilane, heptadecafluoro-1,1,2,2-tetrahydrodecyltriethoxysilane, triethoxy-2-thienylsilane, 3- (triethoxysilyl) And the like.

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

  Among these, 3,3,3-trifluoropropylmethyldimethoxysilane, triethoxy (4- (trifluoromethyl) phenyl) silane, 3,3,3-trifluoropropyltrimethoxysilane, perfluorooctylethyltriethoxysilane , Pentafluorophenyltrimethoxysilane, pentafluorophenyltriethoxysilane, etc. are preferable.

  The content of the organosilane compound in the charge transporting varnish of the present invention is usually about 0.1 to 50% by mass with respect to the total mass of the charge transporting substance and the dopant, but the charge transporting property of the obtained thin film In consideration of suppressing the decrease and enhancing the hole injecting ability to a layer such as the hole transporting layer or the light emitting layer, which is laminated to be in contact with the hole injecting layer on the opposite side to the anode, it is preferably 0. It is about 5 to 40% by mass, more preferably about 0.8 to 30% by mass, and still more preferably about 1 to 20% by mass.

[Tetracyanoquinodimethane compound]
The charge transporting varnish of the present invention preferably contains the tetracyanoquinodimethane compound represented by the formula (6). When the thin film obtained is used as a positive hole injection layer of an organic EL element by containing a tetracyano quinodimethane compound, characteristics, such as the brightness | luminance, further improve. In addition, even when the varnish is fired at a low temperature, a thin film with high flatness and high charge transportability can be produced with good reproducibility.

Wherein, R ¹⁰¹ to R ¹⁰⁴ each independently represent a hydrogen atom or a halogen atom, at least one is a halogen atom. As a halogen atom, the same thing as the above is mentioned, A fluorine atom or a chlorine atom is preferable, and a fluorine atom is more preferable. In addition, at least two of R ^{101 to} R ¹⁰⁴ are preferably halogen atoms, more preferably at least three are halogen atoms, and most preferably all are halogen atoms.

  Specific examples of the tetracyanoquinodimethane compound include tetrafluorotetracyanoquinodimethane (F4TCNQ), tetrachlorotetracyanoquinodimethane, 2-fluorotetracyanoquinodimethane, 2-chlorotetracyanoquinodimethane, 2 Examples include 5-difluorotetracyanoquinodimethane, 2,5-dichlorotetracyanoquinodimethane and the like. Particularly preferred as the tetracyanoquinodimethane compound is F4TCNQ.

  The content of the tetracyanoquinodimethane compound in the charge transporting varnish of the present invention is preferably 0.0001 to 1 equivalent, more preferably 0.001 to 0.5 equivalent, still more preferably 0 with respect to the thiophene derivative. .01 to 0.2 equivalents.

[Other ingredients]
The charge transporting varnish of the present invention may contain, in addition to the thiophene derivative described above, other charge transporting substances as long as the effects of the present invention are not impaired. In addition, the charge transporting varnish of the present invention may contain other substance as a dopant instead of the above-mentioned heteropoly acid.

  As other charge transporting substances, for example, oligoaniline derivatives described in JP-A-2002-151272, oligoaniline compounds described in WO 2004/105446, 1,4- described in WO 2005/043962 Examples thereof include compounds having a dithiin ring, oligoaniline compounds described in WO 2008/032617, oligoaniline compounds described in WO 2008/032616, aryl diamine compounds described in WO 2013/042623, and the like.

  Among other charge transport materials, aniline derivatives are preferred, and in view of solubility in organic solvents, their molecular weight is preferably 4,000 or less, more preferably 3,000 or less, and even more preferably 2, It is less than 000.

Examples of aniline derivatives that can be suitably used as other charge transporting substances in the present invention include those represented by Formula (7).

B ¹ represents a single bond, -NH-, -CH _2- , -S- or -O-, preferably a single bond or -NH-.

R ²⁰¹ to R ²⁰⁶ are each independently a hydrogen atom, a halogen atom, an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^201, which may be 2-20 carbons substituted with Z ²⁰¹ alkenyl group, an alkynyl group which may C2-20 optionally substituted by Z ^201, which may be substituted aryl group having 6 to 20 carbon atoms in Z ^202, carbon atoms, which may be substituted with Z ²⁰² 2-20 heteroaryl group, -OY ²⁰¹ group, -SY ²⁰² group, -NHY ^203, representing the -NY ²⁰⁴ Y ²⁰⁵ groups, or -NHC (O) Y ²⁰⁶ groups. Y ²⁰¹ to Y ²⁰⁶ each independently represent an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^201, alkenyl group which may C2-20 optionally substituted by Z ^201, with Z ²⁰¹ an optionally substituted alkynyl group having 2 to 20 carbon atoms, heteroaryl aryl or Z ²⁰² good 2 to 20 carbon atoms optionally substituted by from 6 to 20 carbon atoms which may be substituted with Z ²⁰² Represents a group. As specific examples of such a halogen atom, an alkyl group, an alkenyl group, an alkenyl group, an aryl group and a heteroaryl group, the same as described above can be mentioned.

Z ²⁰¹ is a halogen atom, a nitro group, a cyano group, an aldehyde group, hydroxy group, thiol group, sulfonic acid group, a carboxylic acid group, an aryl group, or Z ²⁰³ of carbon atoms which may be have 6-20 substituted with Z ²⁰³ And a heteroaryl group having 2 to 20 carbon atoms which may be substituted with
Z ²⁰² is a halogen atom, a nitro group, a cyano group, an aldehyde group, hydroxy group, thiol group, sulfonic acid group, a carboxylic acid group, an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^203, Z ²⁰³ And an alkenyl group of 2 to 20 carbon atoms which may be substituted or an alkynyl group of 2 to 20 carbon atoms which may be substituted by Z ²⁰³ .
Z ²⁰³ represents a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a sulfonic acid group or a carboxylic acid group.

R ^{201 to} R ^{204 each} represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms which may be substituted with Z ²⁰¹ , an aryl group having 6 to 20 carbon atoms which may be substituted with Z ²⁰² , The alkoxy group having 1 to 20 carbon atoms which may be substituted with Z ²⁰¹ (ie, -OY ²⁰¹ group which is an alkyl group having 1 to 20 carbon atoms which Y ²⁰¹ may be substituted with Z ²⁰¹ ) is preferable, hydrogen atom, a fluorine atom, an alkyl group having carbon atoms which may be have 1 to 10 substituted by Z ^201, which may be substituted aryl group having 6 to 14 carbon atoms in Z ^202, which may be substituted with Z ²⁰¹ An alkoxy group having 1 to 10 carbon atoms is more preferable, and a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms optionally substituted by Z ²⁰¹ , and 6 to 10 optionally substituted by Z ²⁰² aryl group, optionally carbon substituted with Z ²⁰¹ More preferably more an alkoxy group having 1 to 6, a hydrogen atom, a fluorine atom, an optionally substituted alkyl group having 1 to 6 carbon atoms in Z ^201, Z ²⁰¹ carbon atoms which may be substituted with 1-6 More preferred is an alkoxy group, with a hydrogen atom being most preferred.

On the other hand, as R ²⁰⁵ and R ²⁰⁶ , a dialkylamino group which is a hydrogen atom, a halogen atom, or an alkyl group having 1 to 20 carbon atoms in which each alkyl group may be substituted with Z ²⁰¹ (ie, Y ²⁰⁴ and Y ^{And C 205} -C 20 alkyl group optionally substituted with Z ²⁰¹ -NY ²⁰⁴ Y ²⁰⁵ group), or each aryl group optionally substituted with Z ^202- C 6-20 carbon atoms The aryl group is preferably a diarylamino group (ie, Y ²⁰⁴ and Y ²⁰⁵ are aryl groups having 6 to 20 carbon atoms which may be substituted with Z ²⁰¹ -NY ²⁰⁴ Y ²⁰⁵ group), and a hydrogen atom or a fluorine atom And a dialkylamino group in which each alkyl group is an alkyl group having 1 to 20 carbon atoms which may be substituted by Z ²⁰¹ , or each aryl group is ^optionally substituted by Z ²⁰² . It is an aryl group More preferably a diarylamino group, a hydrogen atom, more preferably a diarylamino group substituted aryl group having 6 to 20 carbon atoms which may in each aryl group Z ^202, at the same time hydrogen atoms or each aryl group Further preferred is a diarylamino group which is an aryl group having 6 to 20 carbon atoms which may be substituted with Z ²⁰² .

  In the formula (7), p and q each independently represent an integer of 0 or more and satisfy 2 ≦ p + q ≦ 20, preferably 2 ≦ p + q ≦ 8, more preferably 2 ≦ p + q ≦ 6, and still more preferably Satisfies 2 ≦ p + q ≦ 4.

In particular, the R ²⁰¹ to R ²⁰⁶ and Y ²⁰¹ ~Y ^206, Z ²⁰¹ is an aryl group having 6 to 20 carbon atoms are preferable optionally substituted by Z ^202, a phenyl group which may be substituted with Z ²⁰² Is more preferred, and absent (i.e., unsubstituted) is optimal.
Further, Z ²⁰² is preferably an alkyl group having 1 to 20 carbon atoms that may be substituted with Z ^201, more preferably an alkyl group having 1 to 10 carbon atoms optionally substituted by Z ^201, with Z ²⁰¹ The alkyl group having 1 to 8 carbon atoms which may be substituted is more preferable, and the alkyl group having 1 to 6 carbon atoms which may be substituted by Z ²⁰¹ is more preferable and absent (that is, it is unsubstituted) ) Is the best.
Z ²⁰³ is preferably a halogen atom, more preferably fluorine, and most preferably absent (ie, unsubstituted).

Hereinafter, specific examples of the aniline derivative suitable as another charge transporting substance in the present invention will be listed, but the present invention is not limited thereto.

  On the other hand, as other substances to be dopants, for example, benzenesulfonic acid, tosyl acid, p-styrenesulfonic acid, 2-naphthalenesulfonic acid, 4-hydroxybenzenesulfonic acid, 5-sulfosalicylic acid, p-dodecylbenzenesulfonic acid , Dihexylbenzenesulfonic acid, 2,5-dihexylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid, 6,7-dibutyl-2-naphthalenesulfonic acid, dodecylnaphthalenesulfonic acid, 3-dodecyl-2-naphthalenesulfonic acid, hexylnaphthalene sulfone Acid, 4-hexyl-1-naphthalenesulfonic acid, octylnaphthalenesulfonic acid, 2-octyl-1-naphthalenesulfonic acid, hexylnaphthalenesulfonic acid, 7-hexyl-1-naphthalenesulfonic acid, 6-hexyl-2-naphthalate Sulfonic acid, dinonylnaphthalenesulfonic acid, 2,7-dinonyl-4-naphthalenesulfonic acid, dinonylnaphthalenedisulfonic acid, 2,7-dinonyl-4,5-naphthalenedisulfonic acid, as described in WO 2005/000832 1,4-benzodioxane disulfonic acid compounds, aryl sulfonic acid compounds described in WO 2006/025342, aryl sulfonic acid compounds described in WO 2009/096352, polystyrene sulfonic acid Aryl sulfone compounds such as 10; and non-aryl sulfone compounds such as 10-camphorsulfonic acid; 7,7,8,8-tetracyanoquinodimethane (TCNQ), 2,3-dichloro-5,6-dicyano-1,4. -Organic oxidizing agents such as benzoquinone (DDQ) can be mentioned.

  Among these, as other substances to be dopants, arylsulfonic acid compounds are preferable, and in view of solubility in organic solvents, their molecular weight is preferably 3,000 or less, more preferably 2,000 or less, or more Preferably it is 1,000 or less.

In the present invention, examples of the arylsulfonic acid compound which can be suitably used as a dopant include those represented by the formula (8) or (9).

Wherein (8), A ¹ represents an -O- or -S-, -O- is preferable. A ² represents a naphthalene ring or an anthracene ring, preferably a naphthalene ring. A ³ represents a divalent to tetravalent perfluorobiphenyl group, j represents the number of bonds between A ¹ and A ^3, is an integer satisfying 2 ≦ j ≦ 4, A ³ is a divalent perfluoro biphenyl It is preferred that it is a group, preferably perfluorobiphenyl-4,4-diyl, and j is 2. m represents the number of sulfonic acid groups bound to A ² and is an integer satisfying 1 ≦ m ≦ 4, but 2 is preferable.

In formula (9), A ^{4 to} A ⁸ each independently represent a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, or 2 to 20 carbon atoms And at least three of A ^{4 to} A ⁸ are halogen atoms. k represents the number of sulfonic acid groups bonded to the naphthalene ring, and is an integer satisfying 1 ≦ k ≦ 4, preferably 2 to 4, and more preferably 2.

  As the halogenated alkyl group having 1 to 20 carbon atoms, a trifluoromethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2,2-pentafluoroethyl group, a 3,3,3- Trifluoropropyl 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 4-nonafluorobutyl group etc. are mentioned. As a C2-C20 halogenated alkenyl group, a perfluoro vinyl group, 1-perfluoro propenyl group, perfluoro allyl group, perfluoro butenyl group etc. are mentioned.

  Although the thing similar to the above is mentioned as an example of a halogen atom and a C1-C20 alkyl group, As a halogen atom, a fluorine atom is preferable.

Among 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 alkenyl group having 2 to 10 carbon atoms And at least three of A ^{4 to} A ⁸ are preferably a fluorine atom, and a hydrogen atom, a fluorine atom, a cyano group, an alkyl group of 1 to 5 carbon atoms, a fluorinated alkyl of 1 to 5 carbon atoms Group or a fluorinated alkenyl group having 2 to 5 carbon atoms, and at least three of A ^{4 to} A ⁸ are more preferably a fluorine atom, and a hydrogen atom, a fluorine atom, a cyano group, 1 to 5 carbon atoms It is more preferable that A ⁴ , A ⁵ and A ⁸ are a fluorine atom.

  The perfluoroalkyl group is a group in which all hydrogen atoms in the alkyl group are substituted by fluorine atoms, and the perfluoroalkenyl group is a group in which all hydrogen atoms in the alkenyl group are substituted by fluorine atoms.

Specific examples of the arylsulfonic acid compound suitable as a dopant in the present invention will be listed, but the present invention is not limited thereto.

[Charge transportable material]
The charge transportable material of the present invention comprises a charge transportable material comprising a thiophene derivative represented by the formula (1) and a dopant. Such a charge transporting material exhibits good solubility in an organic solvent, and as described above, it is possible to easily produce a charge transporting varnish by dissolving the charge transporting material in an organic solvent. it can.

[Charge transportable thin film]
By applying the charge transporting varnish of the present invention on a substrate and baking it, a charge transporting thin film can be formed on the substrate.

  The method for applying the varnish is not particularly limited, and dip method, spin coating method, transfer printing method, roll coating method, brush coating, ink jet method, spray method etc. may be mentioned, and depending on the coating method It is preferred to adjust the viscosity and surface tension.

  When the varnish of the present invention is used, the firing atmosphere is also not particularly limited, and a thin film having a uniform film-forming surface and high charge transportability not only in the air but also in an inert gas such as nitrogen or vacuum. You can get it.

  The baking temperature is appropriately set in the range of about 100 to 260 ° C. in consideration of the use of the obtained thin film, the degree of charge transportability to be imparted to the obtained thin film, etc. When using as a positive hole injection layer of EL element, about 140-250 degreeC is preferable, and about 145-240 degreeC is more preferable.

  One of the features of the varnish of the present invention is that it can be fired at a low temperature of less than 200 ° C. Even a thin film produced under such firing conditions has high flatness and high charge transportability.

  In addition, at the time of baking, in order to express a higher uniform film formability or to advance a reaction on a base material, two or more temperature changes may be applied. Heating may be performed using a suitable device such as a hot plate or an oven, for example.

  The thickness of the charge transporting thin film is not particularly limited, but is preferably 5 to 200 nm when used as a hole injecting layer of an organic EL element. As a method of changing the film thickness, there are methods such as changing the solid content concentration in the varnish or changing the amount of solution on the substrate at the time of application.

[Organic EL element]
Examples of materials used for producing an OLED element using the charge transporting varnish of the present invention and methods for producing the same include, but are not limited to, the following.

  The electrode substrate to be used is preferably cleaned in advance by liquid cleaning with detergent, alcohol, pure water, etc. For example, in the case of an anode substrate, surface treatment such as UV ozone treatment or oxygen-plasma treatment is performed immediately before use. Is preferred. However, when the anode material contains an organic substance as a main component, the surface treatment may not be performed.

  An example of a method for producing an OLED element having a hole injection layer comprising a thin film obtained from the charge transporting varnish of the present invention is as follows.

  The charge transporting varnish of the present invention is applied onto the anode substrate and baked by the above method to prepare a hole injecting layer on the electrode. This is introduced into a vacuum deposition apparatus, and a hole transport layer, a light emitting layer, an electron transport layer, an electron transport layer / hole block layer, an electron injection layer, and a cathode metal are sequentially deposited to obtain an OLED element. If necessary, an electron blocking layer may be provided between the light emitting layer and the hole transporting layer.

  Examples of the anode material include a transparent electrode represented by indium tin oxide (ITO) and indium zinc oxide (IZO), a metal anode represented by a metal represented by aluminum, an alloy thereof, etc. It is preferable to carry out the chemical treatment. A polythiophene derivative or polyaniline derivative having high charge transportability can also be used.

  Other metals that constitute the metal anode include scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, yttrium, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, cadmium , Indium, scandium, lanthanum, cerium, praseodymium, neomethium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, hafnium, thallium, tungsten, rhenium, osmium, iridium, platinum, gold, titanium And lead, bismuth and alloys thereof, but not limited thereto.

As materials for forming the hole transport layer, (triphenylamine) dimer derivative, [(triphenylamine) dimer] spiro dimer, N, N'-bis (naphthalen-1-yl) -N, N'-bis (Phenyl) -benzidine (α-NPD), N, N′-bis (naphthalen-2-yl) -N, N′-bis (phenyl) -benzidine, N, N′-bis (3-methylphenyl)- N, N'-bis (phenyl) -benzidine, N, N'-bis (3-methylphenyl) -N, N'-bis (phenyl) -9,9-spirobifluorene, N, N'-bis ( Naphthalen-1-yl) -N, N′-bis (phenyl) -9,9-spirobifluorene, N, N′-bis (3-methylphenyl) -N, N′-bis (phenyl) -9, 9-Dimethyl-fluorene, N, N'-bis (naphthalen-1-yl) -N, N'-bis (phenyl) -9,9-dimethyl-fluorene N, N'-bis (3-methylphenyl) -N, N'-bis (phenyl) -9,9-diphenyl-fluorene, N, N'-bis (naphthalen-1-yl) -N, N ' -Bis (phenyl) -9,9-diphenyl-fluorene, N, N'-bis (naphthalen-1-yl) -N, N'-bis (phenyl) -2,2'-dimethylbenzidine, 2,2 ' , 7,7'-Tetrakis (N, N-diphenylamino) -9,9-spirobifluorene, 9,9-bis [4- (N, N-bis-biphenyl-4-yl-amino) phenyl]- 9H-fluorene, 9,9-bis [4- (N, N-bis-naphthalen-2-yl-amino) phenyl] -9H-fluorene, 9,9-bis [4- (N-naphthalen-1-yl) -N-phenylamino) -phenyl] -9H-fluorene, 2,2 ', 7,7'-tetrakis [N-naphthalenyl (phenyl) -amino] -9,9 Spirobifluorene, N, N'-bis (phenanthrene-9-yl) -N, N'-bis (phenyl) -benzidine, 2,2'-bis [N, N-bis (biphenyl-4-yl) amino ] -9,9-spirobifluorene, 2,2'-bis (N, N-diphenylamino) -9,9-spirobifluorene, di- [4- (N, N-di (p-tolyl) amino] ) -Phenyl] cyclohexane, 2,2 ′, 7,7′-tetra (N, N-di (p-tolyl) amino) -9,9-spirobifluorene, N, N, N ′, N′-tetra -Naphthalen-2-yl-benzidine, N, N, N ', N'-tetra- (3-methylphenyl) -3,3'-dimethylbenzidine, N, N'-di (naphthalenyl) -N, N' -Di (naphthalen-2-yl) -benzidine, N, N, N ', N'-tetra (naphthalenyl) -benzidine, N, N'-di (naphthalen-2-yl) -N, N'-diphenyl Benzidine-1,4-diamine, N ¹ , N ⁴ -diphenyl-N ¹ , 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 ′, 4 ′ ′-Tris [3-methylphenyl (phenyl) amino] triphenylamine (m-MTDATA), 4,4 ′, 4 ′ ′-tris [1-naphthyl (phenyl) amino] triphenylamine Triarylamines such as (1-TNATA), 5,5 ′ ′-bis- {4- [bis (4-methylphenyl) amino] phenyl} -2,2 ′: 5 ′, 2 ′ ′-terthiophene Oligothiophenes, such as (BMA-3T), etc. are mentioned.

As a material for forming the light emitting layer, tris (8-quinolinolato) aluminum (III) (Alq _3), bis (8-quinolinolato) zinc (II) (Znq _2), bis (2-methyl-8-quinolinolato) - 4- (p-phenylphenolate) aluminum (III) (BAlq), 4,4′-bis (2,2-diphenylvinyl) biphenyl, 9,10-di (naphthalen-2-yl) anthracene, 2-t -Butyl-9,10-di (naphthalen-2-yl) anthracene, 2,7-bis [9,9-di (4-methylphenyl) -fluoren-2-yl] -9,9-di (4-) Methylphenyl) fluorene, 2-methyl-9,10-bis (naphthalen-2-yl) anthracene, 2- (9,9-spirobifluoren-2-yl) -9,9-spirobifluorene, 2,7 -Bis (9,9-spirobifluoren-2-yl) -9,9 Spirobifluorene, 2- [9,9-di (4-methylphenyl) -fluoren-2-yl] -9,9-di (4-methylphenyl) fluorene, 2,2'-dipyrenyl-9,9- Spirobifluorene, 1,3,5-tris (pyren-1-yl) benzene, 9,9-bis [4- (pyrenyl) phenyl] -9H-fluorene, 2,2′-bi (9,10-diphenyl) Anthracene), 2,7-dipyrenyl-9,9-spirobifluorene, 1,4-di (pyren-1-yl) benzene, 1,3-di (pyren-1-yl) benzene, 6,13-di (Biphenyl-4-yl) pentacene, 3,9-di (naphthalen-2-yl) perylene, 3,10-di (naphthalen-2-yl) perylene, tris [4- (pyrenyl) -phenyl] amine, 10 10'-di (biphenyl-4-yl) -9,9'-bianthracene, N, N'-di (naphthalene 1-yl) -N, N′-diphenyl- [1,1 ′: 4 ′, 1 ′ ′: 4 ′ ′, 1 ′ ′ ′-quaternaryphenyl] -4,4 ′ ′ ′-diamine, 4,4 '-Di [10- (naphthalen-1-yl) anthracene-9-yl] biphenyl, dibenzo {[f, f']-4,4 ', 7,7'-tetraphenyl} diindeno [1,2,3 -Cd: 1 ', 2', 3'-Im] perylene, 1- (7- (9, 9'-bianthracene-10-yl) -9, 9-dimethyl-9H-fluoren-2-yl) pyrene 1- (7- (9,9'-bianthracene-10-yl) -9,9-dihexyl-9H-fluoren-2-yl) pyrene, 1,3-bis (carbazol-9-yl) benzene, 1,3,5-tris (carbazol-9-yl) benzene, 4,4 ′, 4 ′ ′-tris (carbazol-9-yl) triphenylamine, 4,4′-bis (carbazol-9-yl) Biphenyl (CBP) 4,4'-bis (carbazol-9-yl) -2,2'-dimethylbiphenyl, 2,7-bis (carbazol-9-yl) -9,9-dimethylfluorene, 2,2 ', 7,7 '-Tetrakis (carbazol-9-yl) -9,9-spirobifluorene, 2,7-bis (carbazol-9-yl) -9,9-di (p-tolyl) fluorene, 9,9-bis [ 4- (Carbazol-9-yl) -phenyl] fluorene, 2,7-bis (carbazol-9-yl) -9,9-spirobifluorene, 1,4-bis (triphenylsilyl) benzene, 1,3 -Bis (triphenylsilyl) benzene, bis (4-N, N-diethylamino-2-methylphenyl) -4-methylphenylmethane, 2,7-bis (carbazol-9-yl) -9,9-dioctylfluorene 4,4 ′ ′-di (triphenylsilyl) -p-terphenyl 4,4'-di (triphenylsilyl) biphenyl, 9- (4-t-butylphenyl) -3,6-bis (triphenylsilyl) -9H-carbazole, 9- (4-t-butylphenyl)- 3,6-ditrityl-9H-carbazole, 9- (4-t-butylphenyl) -3,6-bis (9- (4-methoxyphenyl) -9H-fluoren-9-yl) -9H-carbazole, 2 , 6-Bis (3- (9H-carbazol-9-yl) phenyl) pyridine, triphenyl (4- (9-phenyl-9H-fluoren-9-yl) phenyl) silane, 9,9-dimethyl-N, N-diphenyl-7- (4- (1-phenyl-1H-benzo [d] imidazol-2-yl) phenyl) -9H-fluoren-2-amine, 3,5-bis (3- (9H-carbazole-) 9-yl) phenyl) pyridine, 9,9-spirobifluo Ren-2-yl-diphenyl-phosphine oxide, 9,9 '-(5- (triphenylsilyl) -1,3-phenylene) bis (9H-carbazole), 3- (2,7-bis (diphenylphosphoryl) -9-phenyl-9H-fluoren-9-yl) -9-phenyl-9H-carbazole, 4,4,8,8,12,12-hexa (p-tolyl) -4H-8H-12H-12C-azadibenzo [cd, mn] pyrene, 4,7-di (9H-carbazol-9-yl) -1,10-phenanthroline, 2,2'-bis (4- (carbazol-9-yl) phenyl) biphenyl, 2,2,- 8-Bis (diphenylphosphoryl) dibenzo [b, d] thiophene, bis (2-methylphenyl) diphenylsilane, bis [3,5-di (9H-carbazol-9-yl) phenyl] diphenylsilane, 3,6- Bis (carbazole-9-a) B) -9- (2-ethyl-hexyl) -9H-carbazole, 3- (diphenylphosphoryl) -9- (4- (diphenylphosphoryl) phenyl) -9H-carbazole, 3,6-bis [(3,5) -Diphenyl) phenyl] -9-phenylcarbazole etc. may be mentioned, You may form a light emitting layer by co-evaporating with a luminescent dopant.

As a light emitting dopant, 3- (2-benzothiazolyl) -7- (diethylamino) coumarin, 2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H, 11H-10- (2-benzothiazolyl) quinolizino [9,9a, 1gh] coumarin, quinacridone, N, N'-dimethyl-quinacridone, tris (2-phenylpyridine) iridium (III) (Ir (ppy) ₃ ), bis (2-phenyl) Pyridine) (acetylacetonate) iridium (III) (Ir (ppy) ₂ (acac)), tris [2- (p- tolyl) pyridine] 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- (2-hydroxyphenyl) benzothiazolato] zinc (II), N ¹⁰ , N ¹⁰ , N ¹⁰ , N ¹⁰ -tetra (p-tolyl) -9,9'-bian Anthracene -10,10'- ^{diamine, N 10, N 10, N} 10, N 10 - tetraphenyl-9,9'-bi anthracene -10,10'- diamine, N ^10, N ¹⁰ - diphenyl -N ^10, N ¹⁰ -Dinaphthalenyl-9,9′-bianthracene-10,10′-diamine, 4,4′-bis (9-ethyl-3-carbazovinylene) -1,1′-biphenyl, perylene, 2,5,8 , 11-tetra-t-butylperylene, 1,4-bis [2- (3-N-ethylcarbazolyl) vinyl] benzene, 4,4'-bis [4- (di-p-tolylamino) styryl] Biphenyl, 4- (di-p-tolylamino) -4 '-[(di-p-tolylamino) styryl] stilbene, bis [3,5-difluoro-2- (2-pyridyl) phenyl- (2-carboxypyridyl) Iridium (III), 4,4′-bis [4- (diphenylamino) styryl] biphenyl, Scan (2,4-difluorophenyl pyridinato) tetrakis (1-pyrazolyl) borate iridium (III), N, N '-bis (naphthalen-2-yl)-N, N'-bis (phenyl)-tris ( 9,9-Dimethylfluorenylene), 2,7-bis {2- [phenyl (m-tolyl) amino] -9,9-dimethyl-fluoren-7-yl} -9,9-dimethyl-fluorene, N -(4-((E) -2- (6 ((E) -4- (diphenylamino) styryl) naphthalen-2-yl) vinyl) phenyl) -N-phenylbenzenamine, fac-iridium (III) tris (1-phenyl-3-methylbenzamide 2-ylidene -C, C ^2), mer- iridium (III) tris (1-phenyl-3-methylbenzamide 2-ylidene -C, C ^{2), 2} , 7-Bis [4- (diphenylamino) styryl] -9,9-spirobi Fluorene, 6-methyl-2- (4- (9- (4- (6-methylbenzo [d] thiazol-2-yl) phenyl) anthracene-10-yl) phenyl) benzo [d] thiazole, 1,4- Di [4- (N, N-diphenyl) amino] styrylbenzene, 1,4-bis (4- (9H-carbazol-9-yl) styryl) benzene, (E) -6- (4- (diphenylamino) Styryl) -N, N-diphenylnaphthalen-2-amine, bis (2,4-difluorophenylpyridinato) (5- (pyridin-2-yl) -1H-tetrazolate) iridium (III), bis (3-) Trifluoromethyl-5- (2-pyridyl) pyrazole) ((2,4-difluorobenzyl) diphenylphosphinate) iridium (III), bis (3-trifluoromethyl-5- (2-pyridyl) pyrazolate) (benzyl) Diphenyl phosphinate) Lysium (III), bis (1- (2,4-difluorobenzyl) -3-methylbenzimidazolium) (3- (trifluoromethyl) -5- (2-pyridyl) -1,2,4-triazolate) Iridium (III), bis (3-trifluoromethyl-5- (2-pyridyl) pyrazolate) (4 ', 6'-difluorophenylpyridinate) iridium (III), bis (4', 6'-difluorophenyl) Pyridinato) (3,5-bis (trifluoromethyl) -2- (2′-pyridyl) pyrrolate) iridium (III), bis (4 ′, 6′-difluorophenylpyridinato) (3- (triyl) Fluoromethyl) -5- (2-pyridyl) -1,2,4-triazolate) iridium (III), (Z) -6-mesityl-N- (6-mesitylquinoline-2 (1H) -ylidene) quinoline 2-amine _{-BF 2, (E) -2- (} 2- (4- ( dimethylamino) styryl) -6- Tyl-4H-pyran-4-ylidene) malononitrile, 4- (dicyanomethylene) -2-methyl-6-durolidyl-9-enyl-4H-pyran, 4- (dicyanomethylene) -2-methyl-6- (1 1,1,7,7-Tetramethyldurolidyl-9-enyl) -4H-pyran, 4- (dicyanomethylene) -2-t-butyl-6- (1,1,7,7-tetramethyldurolizine -4-yl-vinyl) -4H-pyran, tris (dibenzoylmethane) phenanthroline europium (III), 5,6,11,12-tetraphenylnaphthacene, bis (2-benzo [b] thiophen-2-yl -Pyridine) (acetylacetonate) iridium (III), tris (1-phenylisoquinoline) iridium (III), bis (1-phenylisoquinoline) (acetylacetonate) iridium (III), bis [1- (9, 9) - Ethyl-9H-fluoren-2-yl) -isoquinoline] (acetylacetonate) iridium (III), bis [2- (9, 9-dimethyl-9H-fluoren-2-yl) quinoline] (acetylacetonate) iridium (III), tris [4,4'-di-t-butyl- (2,2 ')-bipyridine] ruthenium (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-phenylbenzothiazolato) (acetylacetonate) iridium (III), 5, 10, 15, 20-tetraphenyltetrabenzoporphyrin platinum, osmium (II) bis (3-trifluoromethyl-5- (2-) Pyridine )-Pyrazolate) dimethyl phenyl phosphine, osmium (II) bis (3- (trifluoromethyl) -5- (4- t-butyl pyridyl)-1, 2, 4- triazolate) diphenyl methyl phosphine, osmium (II) bis (3- (trifluoromethyl) -5- (2-pyridyl) -1,2,4-triazole) dimethylphenyl phosphine, osmium (II) bis (3- (trifluoromethyl) -5- (4-t-) Butyl pyridyl) -1,2,4-triazolate) dimethylphenyl phosphine, bis [2- (4-n-hexylphenyl) quinoline] (acetylacetonate) iridium (III), tris [2- (4-n-hexyl) Phenyl) quinoline] iridium (III), tris [2-phenyl-4-methylquinoline] iridium (III), bis (2-phenylquinoline) (2- (3-methylphenyl) pyridinate) iridium (III), bis (2- (9,9-diethyl-fluoren-2-yl) -1-phenyl-1H-benzo [d] imidazolate) (acetylacetonate) iridium (III), bis (2-phenyl) Pyridine) (3- (pyridin-2-yl) -2H-chromen-2-onate) iridium (III), bis (2-phenylquinoline) (2,2,6,6-tetramethylheptane-3,5-) (Geonate) iridium (III), bis (phenylisoquinoline) (2,2,6,6-tetramethylheptane-3,5-dionate) iridium (III), iridium (III) bis (4-phenylthieno [3,2 -c] pyridinato -N, C ²⁾ acetylacetonate, (E) -2- (2- t- butyl-6- (2- (2,6,6-trimethyl-2,4,5,6-tetrahydro -1H-Pyrrolo [3,2,1-ij] quinolin-8-yl) vinyl) -4H-pyran-4-ylide ) Malononitrile, bis (3-trifluoromethyl-5- (1-isoquinolyl) pyrazolate) (methyldiphenylphosphine) ruthenium, bis [(4-n-hexylphenyl) isoquinoline] (acetylacetonate) iridium (III), platinum (II) Octaethylporphine, bis (2-methyldibenzo [f, h] quinoxaline) (acetylacetonate) iridium (III), tris [(4-n-hexylphenyl) xoquinoline] iridium (III) and the like. .

  As materials for forming the electron transport layer / hole block layer, 8-hydroxyquinolinolate-lithium, 2,2 ′, 2 ′ ′-(1,3,5-benzenthryl) -tris (1-phenyl-1) -H-benzimidazole), 2- (4-biphenyl) 5- (4-t-butylphenyl) -1,3,4-oxadiazole, 2,9-dimethyl-4,7-diphenyl-1,10 -Phenanthroline, 4,7-diphenyl-1,10-phenanthroline, bis (2-methyl-8-quinolinolate) -4- (phenylphenolato) aluminum, 1,3-bis [2- (2,2'-bipyridine) -6-yl) -1,3,4-oxadiazo-5-yl] benzene, 6,6'-bis [5- (biphenyl-4-yl) -1,3,4-oxadiazo-2-yl]- 2,2'-bipyridine, 3- (4-biphenyl) -4-phenyl-5-t-butyl Phenyl-1,2,4-triazole, 4- (naphthalen-1-yl) -3,5-diphenyl-4H-1,2,4-triazole, 2,9-bis (naphthalen-2-yl) -4 , 7-diphenyl-1,10-phenanthroline, 2,7-bis [2- (2,2'-bipyridin-6-yl) -1,3,4-oxadiazo-5-yl] -9,9-dimethyl Fluorene, 1,3-bis [2- (4-t-butylphenyl) -1,3,4-oxadiazo-5-yl] benzene, tris (2,4,6-trimethyl-3- (pyridine-3-) Yl) phenyl) borane, 1-methyl-2- (4- (naphthalen-2-yl) phenyl) -1H-imidazo [4,5f] [1,10] phenanthroline, 2- (naphthalen-2-yl)- 4,7-Diphenyl-1,10-phenanthroline, phenyl-dipyrenyl phosphine oxide, 3,3 ' 5,5'-Tetra [(m-pyridyl) -phen-3-yl] biphenyl, 1,3,5-tris [(3-pyridyl) -phen-3-yl] benzene, 4,4'-bis (4,6-Diphenyl-1,3,5-triazin-2-yl) biphenyl, 1,3-bis [3,5-di (pyridin-3-yl) phenyl] benzene, bis (10-hydroxybenzo [ h] Quinolinato) beryllium, diphenylbis (4- (pyridin-3-yl) phenyl) silane, 3,5-di (pyren-1-yl) pyridine and the like.

As materials for forming the electron injection layer, lithium oxide (Li ₂ O), magnesium oxide (MgO), alumina (Al ₂ O ₃ ), lithium fluoride (LiF), sodium fluoride (NaF), magnesium fluoride ( MgF ₂ ), cesium fluoride (CsF), strontium fluoride (SrF ₂ ), molybdenum trioxide (MoO ₃ ), aluminum, Li (acac), lithium acetate, lithium benzoate and the like can be mentioned.

  As a cathode material, aluminum, magnesium-silver alloy, aluminum-lithium alloy, lithium, sodium, potassium, cesium etc. are mentioned.

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

  Although the manufacturing method of the PLED element using the charge transportable varnish of this invention is not specifically limited, The following method is mentioned.

  In the above-described OLED element production, instead of performing vacuum deposition of the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer, the hole transportable polymer layer and the light emitting polymer layer are sequentially formed. A PLED device having a charge transporting thin film formed by the charge transporting varnish of the invention can be produced.

  Specifically, the charge transporting varnish of the present invention is coated on an anode substrate to prepare a hole injecting layer by the above method, and a hole transporting polymer layer and a light emitting polymer layer are sequentially formed thereon. Then, a cathode electrode is vapor deposited to form a PLED element.

  As a cathode and an anode material to be used, the same thing as the time of the said OLED element preparation can be used, and the same washing process and surface treatment can be performed.

  As a method of forming the hole transporting polymer layer and the light emitting polymer layer, it is possible to add a solvent to a hole transporting polymer material, a light emitting polymer material, or a material obtained by adding a dopant thereto, A method of forming a film by uniformly dispersing and applying it on the hole injecting layer or the hole transporting polymer layer and then baking each of them may be mentioned.

  As a hole transportable polymer material, poly [(9,9-dihexylfluorenyl-2,7-diyl) -co- (N, N'-bis {p-butylphenyl} -1,4-diamino] Phenylene)], poly [(9,9-dioctylfluorenyl-2,7-diyl) -co- (N, N'-bis {p-butylphenyl} -1,1'-biphenylene-4,4- Diamine)], poly [(9,9-bis {1'-pentene-5'-yl} fluorenyl-2,7-diyl) -co- (N, N'-bis {p-butylphenyl} -1, 4-diaminophenylene)], poly [N, N′-bis (4-butylphenyl) -N, N′-bis (phenyl) -benzidine] -end-capped with polysilsesquioxane, poly [(9,9) 9-didioctyl fluorenyl-2,7-diyl) -co- (4,4 '-(N- (p-butylphenyl)) diphenylamine)] etc. is mentioned.

  As the light emitting polymer material, polyfluorene derivatives such as poly (9,9-dialkylfluorene) (PDAF), poly (2-methoxy-5- (2′-ethylhexoxy) -1,4-phenylenevinylene) (MEH And polythiophene vinylene derivatives such as -PPV), polythiophene derivatives such as poly (3-alkylthiophene) (PAT), and polyvinylcarbazole (PVCz).

  Examples of the solvent include toluene, xylene, chloroform and the like. As the dissolution or uniform dispersion method, methods such as stirring, heating and stirring, ultrasonic dispersion and the like can be mentioned.

  The coating method is not particularly limited, and examples thereof include an inkjet method, a spray method, a dip method, a spin coating method, a transfer printing method, a roll coating method, and a brush coating. The application is preferably performed under an inert gas such as nitrogen or argon.

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

Hereinafter, the present invention will be more specifically described by way of synthesis examples and examples, but the present invention is not limited to the following examples. In addition, the used apparatus is as follows.
(1) Substrate cleaning: substrate cleaning apparatus (reduced pressure plasma system) manufactured by Choshu Sangyo Co., Ltd.
(2) Application of varnish: Spin coater MS-A100 manufactured by Mikasa Co., Ltd.
(3) Film thickness measurement: manufactured by Kosaka Research Institute, Ltd. Fine shape measuring apparatus Surf coder ET-4000
(4) Fabrication of EL element: Multifunctional deposition system C-E2L1G1-N manufactured by Choshu Sangyo Co., Ltd.
(5) Measurement of luminance, etc. of EL element: IVL measurement system (6) manufactured by Tech World Co., Ltd. (6) Life measurement of EL element (durability test): Organic EL luminance life evaluation system PEL-manufactured by E-Hoc. 105S
(7) NMR measurement: JNM-ECX300 FT NMR SYSTEM manufactured by JEOL Ltd.
(8) MS measurement: Bruker Co. autoflex III smartbem

Synthesis Example 1 Synthesis of Thiophene Derivative 1 (Formula (1-1)) Synthesis of [1] 5-Tributylstannyl-2,2′-bithiophene

  In a reaction vessel, 4.0 g of 2,2′-bithiophene (manufactured by Tokyo Chemical Industry Co., Ltd.) was placed, and after nitrogen substitution, 120 mL of tetrahydrofuran was placed and cooled to −78 ° C. 14.7 mL of n-hexane solution (concentration 1.64 mol / L) of n-butyllithium was dripped maintaining at -78 degreeC, and it stirred for 30 minutes. Furthermore, tri-n-butyl chlorostannane 7.8mL (d 1.20) was dripped there, and after stirring for 10 minutes, it heated up to room temperature and stirred. After 6 hours, the reaction solution was concentrated, 50 mL of n-hexane was added to the obtained residue, and the insoluble matter was removed by filtration (cake washing: n-hexane 30 mL). The obtained filtrate was concentrated and dried to obtain 12.64 g of a dark red oil containing 5-tributylstannyl-2,2'-bithiophene. In addition, purification is not performed any more and the yield is calculated to be 100% (theoretical yield: 10.96 g) in this step to calculate the purity (10.96 / 12.64 × 100 = 86.7%), and the next step Used as a raw material for

[2] Synthesis of Thiophene Derivative 1

After placing 2.0 g of tributylphenylamine (manufactured by Tokyo Chemical Industry Co., Ltd.) and 0.24 g of Pd (PPh ₃ ) ₄ in a reaction vessel and carrying out nitrogen substitution, separately prepared in advance, 5-tributyl synthesized in [1] 100 mL of a dimethylformamide (DMF) solution of 7.8 g of stanyl-2,2'-bithiophene (purity 86.7%) was added. After stirring at 110 ° C. for 2.5 hours, the reaction solution was reprecipitated with 1.5 L of methanol. After the slurry was stirred at room temperature for 15 hours, filtration was performed, and 90 mL of toluene, 10 mL of ethanol and 0.75 g of activated carbon were added to the obtained filtrate, and stirred under reflux conditions for 1 hour. Hot filtration was performed, and the obtained filtrate was cooled to 0 ° C. with stirring, and stirring was continued at 0 ° C. for 2 hours. The slurry was filtered, and the filtrate was dried (80 ° C., 2 hours) to obtain 1.4 g of the target thiophene derivative 1 (yield 47%). The measurement results of ¹ H-NMR and TOF-MS are shown below.
¹ H-NMR (300 MHz, CDCl ₃ ) δ [ppm]: 7.51 (d, J = 8.4 Hz, 6 H), 7.13-7.22 (m, 18 H), 7.01-7.04 (m, 3 H).
MALDI-TOF-MS m / Z found: 737.29 ([M] ⁺ calcd: 737.05)

Example 1-1
0.077 g of thiophene derivative 1 and 0.387 g of phosphotungstic acid (PTA, manufactured by Kanto Chemical Co., Ltd.) were dissolved in 7.5 g of N, N-dimethylacetamide. 7.5 g of diethylene glycol dimethyl ether was added to the obtained solution and stirred, 0.014 g of pentafluorophenyltriethoxysilane was added thereto, and the mixture was stirred to prepare a charge transporting varnish.

[Examples 1-2 and 1-3]
Example 1-1 except that the amounts of the thiophene derivative 1 and PTA used were 0.042 g and 0.422 g (Example 1-2), 0.022 g and 0.353 g (Example 1-3), respectively. The charge transporting varnish was prepared in the same manner as in the above.

Example 1-4
0.062 g of the thiophene derivative 1 and 0.309 g of PTA were dissolved in 3.6 g of 1,3-dimethyl-2-imidazolidinone. To the obtained solution, 2.4 g of 1,3-butanediol and 6.0 g of diethylene glycol dimethyl ether are added and stirred, to which 0.026 g of F4TCNQ (manufactured by Tokyo Chemical Industry Co., Ltd.) is added and stirred, and charge transportability is obtained. A varnish was prepared.

[Example 1-5]
The charge transporting varnish was prepared in the same manner as in Example 1-4 except that the amounts of the thiophene derivative 1 and PTA used were 0.034 g and 0.337 g.

[Example 1-6]
0.052 g of the thiophene derivative 1 and 0.258 g of PTA were dissolved in 3 g of 1,3-dimethyl-2-imidazolidinone. To the resulting solution was added 3 g of 1,3-butanediol and 4 g of diethylene glycol dimethyl ether, and the mixture was stirred, and then 0.031 g of F4TCNQ was added thereto and stirred to prepare a charge transporting varnish.

Example 2-1
The varnish obtained in Example 1-1 is applied to an ITO substrate using a spin coater, dried at 50 ° C. for 5 minutes, and further fired at 150 ° C. for 10 minutes in the air atmosphere to obtain an ITO substrate. A uniform thin film of 30 nm was formed. A 25 mm × 25 mm × 0.7 t glass substrate patterned with indium tin oxide (ITO) on the surface with a film thickness of 150 nm is used as an ITO substrate by an O ₂ plasma cleaning device (150 W, 30 seconds) before use The impurities on the surface were removed.
Next, N, N'-di (1-naphthyl) -N, N'-diphenylbenzidine (.alpha.-) is formed on a thin film formed ITO substrate using a vapor deposition apparatus (vacuum degree 1.0.times.10.sup.- ⁵ Pa). Thin films of NPD), tris (8-quinolinolato) aluminum (III) (Alq ₃ ), lithium fluoride and aluminum were sequentially laminated to obtain an organic EL device. At this time, the deposition rate is 0.2 nm / sec for α-NPD, Alq ₃ and aluminum, and 0.02 nm / sec for lithium fluoride, and the film thickness is 30 nm, 40 nm, 0. It was 5 nm and 120 nm.
In addition, in order to prevent the characteristic degradation by the influence of oxygen in the air, water, etc., after sealing the organic EL element with a sealing substrate, the characteristic was evaluated. Sealing was performed in the following procedure.
The organic EL element is housed between the sealing substrate in a nitrogen atmosphere with an oxygen concentration of 2 ppm or less and a dew point of -85 ° C. or less, and the sealing substrate is bonded with an adhesive (XNR5516Z-B1, manufactured by Nagase ChemteX Co., Ltd.) The At this time, a water-capturing agent (HD-071010W-40, manufactured by Dynik Co., Ltd.) was placed in the sealing substrate together with the organic EL element.
The sealing substrate thus bonded was irradiated with UV light (wavelength: 365 nm, irradiation amount: 6,000 mJ / cm ² ), and then annealed at 80 ° C. for 1 hour to cure the adhesive.

[Examples 2-2 to 2-6]
An organic EL device was manufactured in the same manner as in Example 2-1 except that the varnish obtained in Examples 1-2 to 1-6 was used instead of the varnish obtained in Example 1-1. .

  The current density and luminance at a drive voltage of 5 V of each element were measured. The results are shown in Table 1.

  As shown in Table 1, the varnish of the present invention could realize an organic EL element having excellent luminance characteristics.

The durability test of the element produced by Example 2-1 to 2-6 was done. The half life of the luminance (initial luminance 5,000 cd / m ² ) is shown in Table 2.

  As shown in Table 2, the varnish of the present invention was able to realize an organic EL device having excellent durability.

Claims (10)

It is selected from a charge transportable substance comprising a thiophene derivative represented by the formula (1), a dopant containing a heteropoly acid , an organic solvent, an organic silane compound and a tetracyanoquinodimethane compound represented by the following formula (6) at least one and only containing said organic silane compound is a dialkoxy silane compound, a charge-transporting varnish which comprises a trialkoxysilane compound or tetraalkoxysilane compound.

(Wherein, R ^{1 to} R ²¹ each independently represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a carboxylic acid group, carbon optionally substituted by Z ¹ C 1 -C 20 alkyl group, an alkenyl group which may C2-20 optionally substituted by Z ^1, alkynyl group optionally having 2 to 20 carbon atoms optionally substituted by Z ^1, substituted by Z ² Aryl group having 6 to 20 carbon atoms, -C (O) Y ¹ group, -OY ² group, -SY ³ group, -C (O) OY ⁴ group, -OC (O) Y ⁵ group,- Represents a C (O) NHY ⁶ group or a -C (O) NY ⁷ Y ⁸ group,
Y ¹ to Y ⁸ each independently represent an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^1, alkenyl group which may C2-20 optionally substituted by Z ^1, in Z ¹ Represents a C2-C20 alkynyl group which may be substituted or a C6-C20 aryl group which may be substituted by Z ² ,
Z ¹ represents a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a sulfonic acid group, a carboxylic acid group, or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ³ ;
Z ² is a halogen atom, a nitro group, a cyano group, an aldehyde group, hydroxy group, thiol group, sulfonic acid group, a carboxylic acid group, an alkyl group of Z ³ carbon atoms which may be substituted with 1 to 20, Z ³ And an alkenyl group of 2 to 20 carbon atoms which may be substituted or an alkynyl group of 2 to 20 carbon atoms which may be substituted by Z ³ ;
Z ³ represents a halogen atom, a nitro group, a cyano group, an aldehyde group, a hydroxy group, a thiol group, a sulfonic acid group or a carboxylic acid group,
n ^{1 to} n ³ each independently represent an integer of 2 to 10. )

(Wherein, R ^{101 to} R ¹⁰⁴ each independently represent a hydrogen atom or a fluorine atom, but at least one is a fluorine atom) A charge transportable substance comprising a thiophene derivative represented by the formula (1), a dopant containing a heteropolyacid, an organic solvent, and an organic silane compound, wherein the organic silane compound is a dialkoxysilane compound, a trialkoxysilane The charge transporting varnish according to claim 1, comprising a compound or a tetraalkoxysilane compound. Above R ¹⁰¹ ~ R ¹⁰⁴ The charge transporting varnish according to claim 1, wherein is a fluorine atom. The charge transporting varnish according to any one of claims 1 to 3, wherein the organic silane compound contains dialkoxysilane or trialkoxysilane.   A charge transporting thin film produced using the charge transporting varnish according to any one of claims 1 to 4.   An organic electroluminescent device having the charge transporting thin film according to claim 5.   The organic electroluminescent device according to claim 6, wherein the charge transporting thin film is a hole injecting layer or a hole transporting layer.   A method of producing a charge transporting thin film, comprising applying the charge transporting varnish according to any one of claims 1 to 4 on a substrate and baking it. A method of manufacturing an organic electroluminescent device, comprising using the charge transporting thin film according to claim 5 . A method for producing a charge transporting thin film, comprising the steps of: applying the charge transporting varnish according to any one of claims 1 to 4 on a substrate; and firing it at a temperature of less than 200 ° C.