JP2015092560A - Electric charge transportation type varnish, electric charge transportation type thin film, organic electroluminescent element, and method of manufacturing electric charge transportation type thin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric charge transportation type varnish in which a thin film can be baked at a low temperature of 200°C or less and the film formed under such baking conditions has high flatness and high charge transportability, and which can achieve excellent EL element characteristics when the thin film is applied to an organic EL element.SOLUTION: An electric charge transportation type varnish contains an electric charge transportation type material, a dopant and an organic solvent, the dopant contains heteropoly acid and at least one kind selected from halogenoid tetracyanochinodimethane and halogenoid or cyano benzoquinone.

Description

  The present invention relates to a charge transporting varnish, a charge transporting thin film, an organic electroluminescence (hereinafter referred to as organic EL) element, and a method for producing a charge transporting thin film.

  In an 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. The method for forming the charge transporting thin film is roughly classified into a dry process typified by vapor deposition and a wet process typified by spin coating. Compared with the dry process and the wet process, the wet process can efficiently produce a thin film with a large area and high flatness. Therefore, the thin film is formed by the wet process in a field where a large area of the thin film such as an organic EL is desired. Often formed.

  In view of this point, the present inventors have developed a charge transporting varnish for producing a charge transporting thin film applicable to various electronic devices by a wet process (see, for example, Patent Document 1).

  However, in the field of organic EL in recent years, a substrate made of an organic compound has come to be used instead of a glass substrate due to the trend toward lighter and thinner devices. There is also a need for a varnish that can provide a thin film with good charge transportability.

JP 2002-151272 A

  The present invention has been made in view of the above circumstances, and can be fired at a low temperature of less than 200 ° C., and the thin film produced under such firing conditions has high flatness and high charge transportability. An object is to provide a charge transporting varnish capable of exhibiting excellent characteristics when applied to an organic EL device.

  As a result of intensive studies to achieve the above object, the present inventors have used a heteropolyacid as a dopant and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. The charge transporting varnish can be baked not only at a high temperature of 200 ° C. or higher but also at a low temperature of less than 200 ° C., and the thin film produced under such a baking condition is amorphous and has high flatness and It has been found that an organic EL device having high charge transportability and that can provide excellent luminance characteristics when the thin film is applied to a hole injection layer is completed.

That is, the present invention provides the following charge transporting varnish, charge transporting thin film, organic electroluminescence device, and method for producing the charge transporting thin film.
1. A charge transporting varnish comprising a charge transporting substance, a dopant and an organic solvent, wherein the dopant comprises a heteropolyacid and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. A charge transporting varnish characterized by that.
2. One charge transporting varnish in which the halogenated tetracyanoquinodimethane comprises tetracyanoquinodimethane fluoride.
3. One or two charge transporting varnishes in which the heteropolyacid contains phosphotungstic acid.
4). The charge transporting varnish according to any one of 1 to 3, wherein the charge transporting substance is an aniline derivative or a thiophene derivative.
5. A charge transporting thin film produced using any one of the charge transporting varnishes of 1-4.
An organic electroluminescence device having a charge transporting thin film of 6.5.
7). 6. The organic electroluminescence 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 according to any one of 8.1 to 4 onto a base material and firing at less than 200 ° C.
A method for producing an organic electroluminescent device, comprising using the charge transporting thin film of 9.5.
10. A charge transport material comprising a charge transport material and a dopant, wherein the dopant includes a heteropolyacid and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. A charge transporting material.
11. A method for planarizing a charge transporting thin film using at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone,
Use of a charge transporting varnish containing a charge transporting substance, a dopant and an organic solvent, wherein the dopant contains a heteropolyacid and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. A method for planarizing a charge transporting thin film characterized by the following.

By using the charge transporting varnish of the present invention containing a heteropolyacid as a dopant and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone, not only a high temperature of 200 ° C. or higher Even when fired at a low temperature of less than 200 ° C., it is amorphous, has a high flatness and a high charge transport property, and can realize excellent luminance characteristics when applied to a hole injection layer of an organic EL device Can be obtained. The reason for this is not clear, but by using a halogenated tetracyanoquinodimethane having a high electron accepting ability and a heteropolyacid as a dopant together, crystallization of a thin film that can occur when only one of them is used, This is presumed to be due to the effect of suppressing the lack of doping.
In addition, by using the charge transporting varnish of the present invention, a thin film having excellent charge transporting properties can be produced with good reproducibility even when various wet processes capable of forming a large area such as spin coating and slit coating are used. Therefore, it can sufficiently cope with recent progress in the field of organic EL elements.
Furthermore, the thin film obtained from the charge transport varnish of the present invention can be used as an antistatic film, an anode buffer layer of an organic thin film solar cell, or the like.

[Charge transport varnish]
The charge transporting varnish of the present invention contains a charge transporting substance, a dopant and an organic solvent, and the dopant is at least one selected from a heteropolyacid, a halogenated tetracyanoquinodimethane and a halogenated or cyanated benzoquinone. I.e., at least one selected from halogenated tetracyanoquinodimethane, halogenated benzoquinone and cyanated benzoquinone.

[Charge transport material]
The charge transporting substance contained in the charge transporting varnish of the present invention is a substance having a charge transporting property, that is, conductivity, and may have a charge transporting property by itself. There may be something. In particular, a substance having a hole transporting property is preferable.

  As such a charge transporting substance, a charge transporting compound used in the field of organic EL or the like can be used, and specific examples thereof include oligoaniline derivatives, N, N′-diarylbenzidine derivatives, N, N Arylamine derivatives (aniline derivatives) such as N, N ′, N′-tetraarylbenzidine derivatives, thiophene derivatives such as oligothiophene derivatives, thienothiophene derivatives and thienobenzothiophene derivatives, and pyrrole derivatives such as oligopyrrole.

As the aniline derivative, an aniline derivative that does not have a quinonediimine structure, that is, an aniline derivative that does not have a partial structure represented by the following formula is preferable.

  The quinonediimine structure is a structure (so-called quinoid structure) in which one double bond in the carbocyclic ring of an aromatic compound is reduced and instead two exocyclic double bonds are present in the para or ortho position. The quinonediimine structure derived from an aryldiamine compound having two amino groups in the para position to each other has a structure represented by the following formula.

  The molecular weight of the charge transporting material is not particularly limited as long as it dissolves in the organic solvent used by the charge transporting material, and is about 200 to 10,000. However, a thin film with higher charge transporting property is reproducible. From the viewpoint of obtaining 300 or more, more preferably 400 or more, and from the viewpoint of preparing a uniform varnish that gives a highly flat thin film with good reproducibility, preferably 8,000 or less, more preferably 7,000 or less, 6,000 or less is still more preferable, and 5,000 or less is still more preferable. In addition, from the viewpoint of preventing the charge transporting substances from separating from each other when the film is thinned, the charge transporting compound preferably has no molecular weight distribution (dispersity is 1) (that is, has a single molecular weight). Preferably).

[Dopant]
The charge transport varnish of the present invention contains at least one selected from a heteropolyacid as a first dopant and a halogenated tetracyanoquinodimethane and a halogenated or cyanated benzoquinone as a second dopant. Hereinafter, these are collectively referred to simply as dopants.

  The heteropolyacid as the first dopant typically has a structure in which a hetero atom is located at the center of the molecule, which is represented by a Keggin type represented by the formula (A1) or a Dawson type chemical structure represented by the formula (A2). In addition, it is a polyacid obtained by condensing an isopolyacid that is an oxo acid such as vanadium (V), molybdenum (Mo), or tungsten (W) with an oxo acid of a different element. Examples of such oxo acids of different elements mainly include silicon (Si), phosphorus (P), and arsenic (As) oxo acids.

  Specific examples of the heteropolyacid include phosphomolybdic acid, silicomolybdic acid, phosphotungstic acid, silicotungstic acid, and phosphotungstomolybdic acid. You may use these individually by 1 type or in combination of 2 or more types. In addition, the heteropolyacid used by this invention is available as a commercial item, and can also be synthesize | combined by a well-known method.

  In particular, when one kind of heteropolyacid is used, the heteropolyacid is preferably phosphotungstic acid or phosphomolybdic acid, and more preferably phosphotungstic acid. When two or more types of heteropolyacids are used, at least one of the two or more types of heteropolyacids is preferably phosphotungstic acid or phosphomolybdic acid, and more preferably phosphotungstic acid.

  In addition, in the quantitative analysis such as elemental analysis, the heteropolyacid may be a commercially available product obtained from a structure represented by the general formula or a small number of elements, or a known synthesis method. As long as it is appropriately synthesized according to the above, it can be used in the present invention.

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. In quantitative analysis, even if the number of P (phosphorus), O (oxygen), W (tungsten) or Mo (molybdenum) in this formula is large or small, it is obtained as a commercial product, or As long as it is appropriately synthesized according to a known synthesis method, it can be used in the present invention. In this case, the mass of the heteropolyacid defined in the present invention is not the mass of pure phosphotungstic acid (phosphotungstic acid content) in the synthesized product or commercially available product, but a commercially available form and a known synthesis. In a form that can be isolated by the method, it means the total mass in a state containing hydration water and other impurities.

The halogenated tetracyanoquinodimethane, which is the second dopant, is represented by the formula (1).

In the formula, R ^{1 to} R ⁴ each independently represent a hydrogen atom or a halogen atom, but at least one is a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom or a chlorine atom is preferable, and a fluorine atom is more preferable. In addition, at least two of R ^{1 to} R ⁴ are preferably halogen atoms, more preferably at least three are halogen atoms, and most preferably all are halogen atoms.

  Specific examples of the halogenated tetracyanoquinodimethane include tetrafluorotetracyanoquinodimethane (F4TCNQ), tetrachlorotetracyanoquinodimethane, 2-fluorotetracyanoquinodimethane, 2-chlorotetracyanoquinodimethane, Examples include 2,5-difluorotetracyanoquinodimethane, 2,5-dichlorotetracyanoquinodimethane, and the like. As the halogenated tetracyanoquinodimethane, F4TCNQ is particularly preferable.

Another second dopant, halogenated or cyanated benzoquinone, is represented by formula (2).

In the formula, R ^{5 to} R ⁸ each independently represent a hydrogen atom, a halogen atom or a cyano group, but at least one is a halogen atom or a cyano group. The same thing as the above is mentioned as a halogen atom, A fluorine atom or a chlorine atom is preferable, and a fluorine atom is more preferable. In addition, at least two of R ^{5 to} R ⁸ are preferably a halogen atom or a cyano group, more preferably at least three are a halogen atom or a cyano group, and even more preferably all are a halogen atom or a cyano group. preferable.

  Specific examples of the halogenated or cyanated benzoquinone include 2,3-dichloro-5,6-dicyano-p-benzoquinone, trifluorobenzoquinone, tetrafluorobenzoquinone, tetrabromobenzoquinone, and tetracyanobenzoquinone. The halogenated or cyanated benzoquinone is preferably 2,3-dichloro-5,6-dicyano-p-benzoquinone, trifluorobenzoquinone, tetrafluorobenzoquinone or tetracyanobenzoquinone, more preferably 2,3-dichloro- 5,6-dicyano-p-benzoquinone, tetrafluorobenzoquinone, and tetracyanobenzoquinone, and more preferably 2,3-dichloro-5,6-dicyano-p-benzoquinone.

The dopant content in the charge transporting varnish of the present invention is appropriately determined depending on the charge transporting substance.
When a thiophene derivative is used as a charge transporting substance, the content of the first dopant is usually about 0.01 to 100, more preferably 0.1 to mass ratio with respect to the charge transporting substance made of a thiophene derivative. About 50, more preferably about 1-10. The content of the second dopant is about 0.1 to 100% by mass, more preferably 1 to 50% by mass, even more preferably in the total solid content (referring to components contained in the varnish remaining after firing). Is about 5 to 30% by mass. A compound in which a thiophene site and an aniline site coexist in the molecule is treated as a thiophene derivative in the calculation of the dopant / host ratio.

  On the other hand, when the aniline derivative is used as a charge transporting material, the content of the first dopant is usually about 1 to 500% by mass, preferably about 10 to 200% by mass, more preferably 50 to 150% by mass in the total solid content. %. The content of the second dopant is usually about 0.01 to 100, preferably about 0.1 to 50, more preferably about 1 to 10 in terms of an equivalent ratio with respect to the charge transporting material composed of the aniline derivative. It is.

  The charge transporting varnish of the present invention includes not only high temperature baking at 200 ° C. or higher but also low temperature baking at less than 200 ° C., in some cases 180 ° C. or lower, and even 160 ° C. or lower by including the first and second dopants. It has excellent properties such as brightness, and has high hole acceptability from transparent electrodes typified by indium tin oxide (ITO) and indium zinc oxide (IZO), as well as metals typified by aluminum. It is possible to provide a thin film excellent in charge transport property that exhibits high hole acceptability from the anode.

[Organic solvent]
As the organic solvent used when preparing the charge transporting varnish, a highly soluble solvent capable of satisfactorily dissolving the charge transporting substance, the dopant, and other components described later can be used.
Examples of such highly soluble solvents include organic solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, and diethylene glycol monomethyl ether. Can be used. These solvents can be used alone or in combination of two or more, and the amount used can be 5 to 100% by mass with respect to the total solvent used in the varnish.
Note that both the charge transporting substance and the dopant are preferably completely dissolved in the solvent.

  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 containing at least one high-viscosity organic solvent, it becomes easy to adjust the viscosity of the varnish, and as a result, it is possible to prepare a varnish according to the coating method to be used, which gives a highly flat thin film 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.

  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 where no solid precipitates, and the addition ratio is preferably 5 to 80% by mass as long as no solid precipitates.

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, etc., other solvents are used in an amount of 1 to 90% by mass, preferably It can also be mixed at a ratio of 1 to 50% by mass.
Examples of such solvents include ethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol Examples include, but are not limited to, acetone alcohol, γ-butyrolactone, ethyl lactate, n-hexyl acetate, propylene glycol monomethyl ether, and the like. These solvents can be used alone or in combination of two or more.

The viscosity of the varnish of the present invention is appropriately set according to the thickness of the thin film to be produced and the solid content concentration, but is usually 1 to 50 mPa · s at 25 ° C.
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. In consideration of improving the coatability of the varnish, it is preferably about 0.5 to 5.0% by mass, and more preferably about 1.0 to 3.0% by mass.

[Other ingredients]
The charge transport varnish of the present invention may contain an organosilane compound. Specific examples of the organic silane compound include dialkoxysilane compounds, trialkoxysilane compounds, and tetraalkoxysilane compounds. These can be used alone or in combination of two or more.

  In particular, the organic silane compound preferably includes one selected from dialkoxysilane compounds and trialkoxysilane compounds, and more preferably includes trialkoxysilane compounds.

Examples of the dialkoxysilane compound, trialkoxysilane compound, and tetraalkoxysilane compound include those represented by the 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 Or 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 , Methacryloxy group, acryloxy group, ureido group (—NHCONH ₂ ), thiol group, isocyanate group (—NCO), amino group, —NHY ¹⁰¹ group or —NY ¹⁰² Y ¹⁰³ group.
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 which may having 2 to 20 carbon atoms, an epoxycyclohexyl group, a glycidoxy group, a methacryloxy group, an acryloxy group, a ureido group (-NHCONH _2), thiol group, isocyanate group (-NCO), amino group, -NHY ¹⁰¹ group or —NY ¹⁰² represents a Y ¹⁰³ group.

Y ¹⁰¹ to Y ¹⁰³ each independently, 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.

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

  The alkyl group having 1 to 20 carbon atoms may be linear, branched, or cyclic. For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s -C1-C20 linear or branched such as -butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group 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 cyclic alkyl groups having 3 to 20 carbon atoms such as a bicyclononyl group and a 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- Examples include 1-pentenyl group, n-1-decenyl group, n-1-eicocenyl group and the like.

  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, and n-3-butynyl. 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. Group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group and the like.

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 An optionally substituted methyl group or ethyl group is more preferable.

R ′ is preferably an alkyl group having 1 to 20 carbon atoms which may be substituted with Z ¹⁰³ or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ¹⁰⁴ , and is substituted with Z ^103. More preferably an alkyl group having 1 to 10 carbon atoms which may be substituted or an aryl group having 6 to 14 carbon atoms which may be substituted with Z ¹⁰⁴ , and an alkyl having 1 to 6 carbon atoms which may be substituted with Z ¹⁰³ more preferably more aryl group which may having 6 to 10 carbon atoms optionally substituted by a group or Z ^104, which may be substituted with an alkyl group or Z ¹⁰⁴ of 1 to 4 carbon atoms which may be substituted with Z ¹⁰³ A good phenyl group is more preferred.

  A plurality of R may be the same or different, and a plurality of R ′ may all be the same or different.

Z ¹⁰¹ is preferably a halogen atom or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ¹⁰⁵ , more preferably a fluorine atom or a phenyl group which may be substituted with Z ¹⁰⁵ , and not present ( That is, it is optimal to be unsubstituted.

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 not present (ie, unsubstituted).

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, thiol group, isocyanate group, amino group, good diphenylamino group optionally substituted by a phenyl amino group, or Z ¹⁰⁴ may be substituted with Z ¹⁰⁵ preferably that more preferably a halogen atom, no fluorine atom or presence ( That is, it is even more preferable that it is unsubstituted.

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, acryloxy group, ureido group, a thiol group, isocyanate group, amino group, good diphenylamino group optionally substituted by a phenyl amino group, or Z ¹⁰⁵ may be substituted with Z ¹⁰⁵ preferably, more preferably a halogen atom, fluorine Even more preferred is an atom or absence (ie, unsubstituted).

Z ¹⁰⁵ is preferably a halogen atom, more preferably a fluorine atom or not (that is, unsubstituted).

Hereinafter, although the specific example of the organosilane compound which can be used by this invention is given, it is not limited to these.
Specific examples of dialkoxysilane compounds include dimethyldimethoxysilane, dimethyldiethoxysilane, methylethyldimethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, methylpropyldimethoxysilane, methylpropyldiethoxysilane, diisopropyldimethoxysilane, and phenylmethyl. Dimethoxysilane, vinylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 3-methacryloxy Propylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-aminopropylmethyl 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, hexadecyltrimethoxysilane, hexadecyltriethoxy Silane, octadecyltrimethoxysilane, octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyl Rutrimethoxysilane, 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, pentaful Orophenyltriethoxysilane, 3- (heptafluoroisopropoxy) propyltriethoxysilane, heptadecafluoro-1,1,2,2-tetrahydrodecyltriethoxysilane, triethoxy-2-thienylsilane, 3- (triethoxysilyl) ) Franc etc. are mentioned.

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

  Among these, 3,3,3-trifluoropropylmethyldimethoxysilane, triethoxy (4- (trifluoromethyl) phenyl) silane, 3,3,3-trifluoropropyltrimethoxysilane, perfluorooctylethyltriethoxysilane , Pentafluorophenyltrimethoxysilane, pentafluorophenyltriethoxysilane, and the like 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 thin film obtained is In consideration of suppressing the decrease and increasing the hole injecting ability to a layer laminated so as to be in contact with the hole injecting layer on the side opposite to the anode, such as a hole transporting layer and a light emitting layer, it is preferably 0. It is about 5-40 mass%, More preferably, it is about 0.8-30 mass%, More preferably, it is about 1-20 mass%.

  Any other known dopant may be used in the charge transporting varnish of the present invention as long as the effects of the present invention are not hindered.

  Examples of other dopants include benzenesulfonic acid, tosylic acid, p-styrenesulfonic acid, 2-naphthalenesulfonic acid, 4-hydroxybenzenesulfonic acid, 5-sulfosalicylic acid, p-dodecylbenzenesulfonic acid, and dihexylbenzenesulfonic 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, 6-hexyl-2-naphthalenesulfonic acid, di Nylnaphthalenesulfonic acid, 2,7-dinonyl-4-naphthalenesulfonic acid, dinonylnaphthalenedisulfonic acid, 2,7-dinonyl-4,5-naphthalenedisulfonic acid, described in WO2005 / 000832 , 4-Benzodioxane disulfonic acid compounds, aryl sulfonic acid compounds described in WO 2006/025342, aryl sulfonic acid compounds described in WO 2009/096352, aryl sulfones such as polystyrene sulfonic acid Compound; Non-aryl sulfone compounds such as 10-camphorsulfonic acid and the like can be mentioned.

[Charge transport materials]
The charge transport material of the present invention includes a charge transport material, a dopant and an organic solvent, and the dopant is a heteropolyacid, at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. That is, at least one selected from halogenated tetracyanoquinodimethane, halogenated benzoquinone and cyanated benzoquinone. Such a charge transporting material exhibits good solubility in an organic solvent, and as described above, the charge transporting varnish can be easily produced by dissolving the charge transporting material in an organic solvent. it can.

[Charge transport thin film]
A charge transporting thin film can be formed on a base material by applying the charge transporting varnish of the present invention on the base material and baking it.

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

  Further, when the varnish of the present invention is used, the firing atmosphere is not particularly limited, and a thin film having a uniform film formation surface and a high charge transport property not only in the air atmosphere but also in an inert gas such as nitrogen or in a vacuum. Can be obtained.

  The varnish of the present invention is characterized in that it can be baked not only at a high temperature of 200 ° C. or higher but also at a low temperature of less than 200 ° C. The firing temperature is appropriately set within a range of 100 ° C. or more and less than 250 ° C. in consideration of the use of the obtained thin film, the degree of charge transportability imparted to the obtained thin film, the type of solvent, etc. When using the obtained thin film as a hole transport layer or a hole injection layer of an organic EL device, about 130 to 245 ° C is preferable, and about 140 to 240 ° C is more preferable.

  In firing, two or more steps of temperature change may be applied for the purpose of expressing higher uniform film forming property or allowing the reaction to proceed on the substrate. The heating may be performed using an appropriate device such as a hot plate or an oven.

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

  Since the charge transporting thin film of the present invention is produced using the above-described charge transporting varnish of the present invention, it has excellent flatness as well as charge transporting property.

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

  The electrode substrate to be used is preferably cleaned in advance by cleaning with a liquid such as a detergent, alcohol, or pure water. For example, the anode substrate is subjected to surface treatment such as UV ozone treatment or oxygen-plasma treatment immediately before use. It is preferable. However, when the anode material is mainly composed of an organic material, the surface treatment may not be performed.

  The example of the manufacturing method of the OLED element which has a positive hole injection layer which consists of a thin film obtained from the charge transportable varnish of this invention is as follows.

  By the above method, the charge transporting varnish of the present invention is applied onto the anode substrate and baked to produce a hole injection 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 form an OLED element. If necessary, an electron blocking layer may be provided between the light emitting layer and the hole transport layer.

  Examples of the anode material include transparent electrodes typified by indium tin oxide (ITO) and indium zinc oxide (IZO), metal anodes typified by aluminum, alloys thereof, and the like. What performed the chemical conversion process is preferable. Polythiophene derivatives and polyaniline derivatives having high charge transporting properties can also be used.

  Other metals constituting 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, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, hafnium, thallium, tungsten, rhenium, osmium, iridium, platinum, gold, titanium Lead, bismuth, and alloys thereof, but are not limited thereto.

As a material 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 (phenanthren-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 ″ -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 And oligothiophenes such as (BMA-3T).

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 ′ ″-quarterphenyl] -4,4 ′ ″-diamine, 4,4 '-Di [10- (naphthalen-1-yl) anthracen-9-yl] biphenyl, dibenzo {[f, f']-4,4 ', 7,7'-tetraphenyl} diindeno [1,2,3 -Cd: 1 ', 2', 3'-lm] perylene, 1- (7- (9,9'-bianthracen-10-yl) -9,9-dimethyl-9H-fluoren-2-yl) pyrene 1- (7- (9,9′-bianthracen-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 Len-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, 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 ) -9- (2-ethyl-hexyl) -9H-carbazole, 3- (diphenylphosphoryl) -9- (4- (diphenylphosphoryl) phenyl) -9H-carbazole, 3,6-bis [(3,5 -Diphenyl) phenyl] -9-phenylcarbazole and the like, and a light-emitting layer may be formed by co-evaporation with a light-emitting dopant.

As the luminescent dopant, 3- (2-benzothiazolyl) -7- (diethylamino) coumarin, 2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H, 11H-10- (2-Benzothiazolyl) quinolidino [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 Tracene-10,10′-diamine, N ¹⁰ , N ¹⁰ , N ¹⁰ , N ¹⁰ -tetraphenyl-9,9′-bianthracene-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, (2,4-difluorophenylpyridinato) tetrakis (1-pyrazolyl) borateiridium (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) anthracen-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 Diphenylphosphinate) Lidium (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- (tri 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- Til-4H-pyran-4-ylidene) malononitrile, 4- (dicyanomethylene) -2-methyl-6-julolidyl-9-enyl-4H-pyran, 4- (dicyanomethylene) -2-methyl-6- (1 , 1,7,7-Tetramethyljulolidyl-9-enyl) -4H-pyran, 4- (dicyanomethylene) -2-tert-butyl-6- (1,1,7,7-tetramethyljulolidine -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 - Til-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-Phenylbenzothiazolate) (acetylacetonate) iridium (III), 5,10,15,20-tetraphenyltetrabenzoporphyrin platinum, osmium (II) bis (3-trifluoromethyl-5- (2- Pyridine ) -Pyrazolate) dimethylphenylphosphine, osmium (II) bis (3- (trifluoromethyl) -5- (4-tert-butylpyridyl) -1,2,4-triazolate) diphenylmethylphosphine, osmium (II) bis (3- (trifluoromethyl) -5- (2-pyridyl) -1,2,4-triazole) dimethylphenylphosphine, osmium (II) bis (3- (trifluoromethyl) -5- (4-t- Butylpyridyl) -1,2,4-triazolate) dimethylphenylphosphine, 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) irid (III), bis (2- (9,9-diethyl-fluoren-2-yl) -1-phenyl-1H-benzo [d] imidazolato) (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- Diate) 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), etc. .

  As a material for forming the electron transport layer / hole blocking layer, 8-hydroxyquinolinolate-lithium, 2,2 ′, 2 ″-(1,3,5-benztolyl) -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-dipyrenylphosphine 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.

Materials for forming the electron injection layer include 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.

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

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

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

  In the preparation of the OLED element, instead of performing the vacuum deposition operation of the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer, the hole transport polymer layer and the light emitting polymer layer are sequentially formed. A PLED element 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 applied on the anode substrate to prepare a hole injection 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 obtain a PLED element.

  As the cathode and anode material to be used, the same materials as those used in the production of the OLED element can be used, and the same cleaning treatment and surface treatment can be performed.

  As a method for forming the hole transporting polymer layer and the light emitting polymer layer, a hole transporting polymer material or a light emitting polymer material, or a material in which a dopant is added to these materials are added and dissolved, The method of forming into a film by disperse | distributing uniformly and apply | coating on a positive hole injection layer or a positive hole transportable polymer layer, and baking each is mentioned.

  As the hole transporting 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'-penten-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] -endcapped with polysilsesquioxane, poly [(9, 9-didioctylfluorenyl-2,7-diyl) -co- (4,4 ′-(N- (p-butylphenyl)) diphenylamine)] and the like.

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

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

  The application method is not particularly limited, and examples thereof include an inkjet 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 performed under an inert gas such as nitrogen or argon.

  Examples of the firing method include a method of heating in an oven or a hot plate under an inert gas or in a vacuum.

EXAMPLES Hereinafter, although a synthesis example, an Example, and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to the following Example. In addition, the apparatus used is as follows.
(1) Substrate cleaning: Choshu Sangyo Co., Ltd. substrate cleaning equipment (decompressed plasma method)
(2) Varnish application: Mikasa Co., Ltd. spin coater MS-A100
(3) Film thickness measurement: Kosaka Laboratory Co., Ltd. Fine shape measuring machine Surfcorder ET-4000
(4) Production of EL element: Choshu Sangyo Co., Ltd. Multifunctional deposition system C-E2L1G1-N
(5) Measurement of luminance of EL element: (Yes) Tech World IVL measurement system (6) EL element lifetime measurement (durability evaluation): Organic EL luminance lifetime evaluation system PEL- 105S
(7) NMR measurement: JNM-ECX300 FT NMR SYSTEM manufactured by JEOL Ltd.
(8) MS measurement: Bruker autoflex III smartbem

[1] Synthesis of Compound [Synthesis Example 1] Synthesis of thiophene derivative 2 A thiophene derivative 2 (TP2) represented by the formula (X1) was synthesized by the following method.

Into the flask, 2.0 g of 2,3-dihydrothieno [3,4-b] [1,4] dioxin and 150 mL of tetrahydrofuran were placed and purged with nitrogen, followed by cooling to -78 ° C. Thereto, 10 mL of n-butyllithium n-hexane solution (concentration 1.64 mol / L) was added dropwise, stirred at −78 ° C. for 30 minutes, then heated to −40 ° C., and 5 mL of tributylchlorostannane was added. After dropping, the temperature was raised to room temperature, and the mixture was further stirred for 16 hours.
After completion of the stirring, the reaction mixture was concentrated, the concentrated solution and n-hexane were mixed, and it was filtered. Then, the obtained filtrate was concentrated to obtain 7.4 g of a mixture containing tributyl (2,3-dihydrothieno [3,4-b] [1,4] dioxin-5-yl) stannane.
Next, in another flask, 1.5 g of 5,5′-dibromo-2,2′-bithiophene and 0.27 g of tetrakis (triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ) were added and purged with nitrogen. . Thereto, 6.2 g of a mixture containing the above tributyl (2,3-dihydrothieno [3,4-b] [1,4] dioxin-5-yl) stannane and 20 mL of N, N-dimethylformamide were added, and 125 ° C. The mixture was warmed to 2 hours and stirred for 2 hours.
After completion of stirring, the mixture was allowed to cool to room temperature, and n-hexane was added thereto for liquid separation, and the obtained N, N-dimethylformamide layer was dropped into a mixed solution of ion-exchanged water and methanol for reprecipitation. .
The precipitate was collected by filtration and dried to obtain TP2 (yield 1.4 g, yield 66%). The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (CDCL ₃ ) δ: 7.11 (d, J = 4.2Hz, 2H), 7.07 (d, J = 4.2Hz, 2H), 6.23 (s, 2H), 4.37-4.33 (m, 4H), 4.28-4.24 (m, 4H).

[Synthesis Example 2] Synthesis of thiophene derivative 3 (1) Synthesis of 5-tributylstannyl-2,2'-bithiophene

  4.0 g of 2,2′-bithiophene (manufactured by Tokyo Chemical Industry Co., Ltd.) was placed in a reaction vessel and purged with nitrogen, and then 120 mL of tetrahydrofuran was added and cooled to −78 ° C. While maintaining at −78 ° C., 14.7 mL of n-butyllithium in n-hexane (concentration 1.64 mol / L) was added dropwise and stirred for 30 minutes. Further, 7.8 mL (d 1.20) of tri-n-butylchlorostannane was added dropwise thereto and stirred for 10 minutes, and then the mixture was warmed to room temperature and stirred. After 6 hours, the reaction solution was concentrated, 50 mL of n-hexane was added to the resulting residue, and insoluble materials were removed by filtration (cake washing: 30 mL of n-hexane). The obtained filtrate was concentrated and dried to obtain 12.64 g of dark red oil containing 5-tributylstannyl-2,2′-bithiophene. Further, no further purification was performed, and the purity was calculated assuming that the yield of this step was 100% (theoretical yield 10.96 g) (10.96 / 12.64 × 100 = 86.7%). Used as raw material.

(2) Synthesis of thiophene derivative 3 A thiophene derivative 3 (TP3) represented by the formula (X4) was synthesized by the following method.

After putting 2.0 g of tributylphenylamine (manufactured by Tokyo Chemical Industry Co., Ltd.) and 0.24 g of Pd (PPh ₃ ) ₄ into the reaction vessel and substituting with nitrogen, 5-tributylstannyl-2 synthesized in (1), 100 mL of a dimethylformamide (DMF) solution of 7.8 g (purity 86.7%) of 2′-bithiophene was added. After stirring at 110 ° C. for 2.5 hours, the reaction solution was reprecipitated with 1.5 L of methanol. The slurry was stirred at room temperature for 15 hours and then filtered. To the obtained filtrate, 90 mL of toluene, 10 mL of ethanol and 0.75 g of activated carbon were added, and the mixture was stirred for 1 hour under reflux conditions. Filtration was performed while hot, and the resulting filtrate was cooled to 0 ° C. with stirring, and stirring was continued at 0 ° C. for 2 hours. The slurry was filtered, and the residue was dried (80 ° C., 2 hours) to obtain TP3 (yield 1.4 g, 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, 6H), 7.13-7.22 (m, 18H), 7.01-7.04 (m, 3H).
MALDI-TOF-MS m / Z found: 737.29 ([M] ⁺ calcd: 737.05)

[Synthesis Example 3] Synthesis of thiophene derivative 4 A thiophene derivative 4 (TP4) represented by the formula (X2) was synthesized by the following method.

Thienothiophene (manufactured by Tokyo Chemical Industry Co., Ltd.) (2.00 g) and dimethylformamide (DMF) (30 mL) were placed in a reaction vessel and stirred at room temperature to confirm dissolution. 4 eq) was charged as powder. After confirming disappearance of the raw materials, n-hexane and ion-exchanged water were added to the reaction solution to carry out liquid separation. The organic layer was washed once with ion-exchanged water and saturated brine, and then dried over Na ₂ SO ₄ . The solvent was distilled off under reduced pressure and dried to obtain 4.21 g of the desired thienothiophene dibromo compound (yield 99%).
Subsequently, under a nitrogen atmosphere, 1.93 g of thienothiophene dibromo compound, 0.75 g (10 mol%) of Pd (PPh ₃ ) ₄ , 4.00 g of 3-hexylthiopheneboronic acid pinacol ester (manufactured by Aldrich), dimethoxyethane (DME) 43 mL and 16.2 mL (5 eq) of a ₂ mol / L aqueous solution of K ₂ CO ₃ were added, and the reaction was stirred for 5 hours under reflux with heating. After completion of the reaction, n-hexane was added, and the mixture was stirred at room temperature for 30 minutes. Insoluble matters were removed by filtration, and the filtrate was washed twice with ion-exchanged water and once with saturated brine. After drying over Na ₂ SO ₄ , the solvent was distilled off under reduced pressure, and the residue was separated and purified by column chromatography to obtain TP4 (yield 85%). The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (300 MHz, CDCl ₃ ) δ [ppm]: 7.24 (s, 2H), 7.21 (d, J = 5.1 Hz, 2H), 6.96 (d, J = 5.3 Hz, 2H), 2.79 (t, J = 7.4Hz, 4H), 1.60-1.70 (m, 4H), 1.27-1.42 (m, 12H), 0.88 (t, J = 6.9Hz, 6H).

[Synthesis Example 4] Synthesis of thiophene derivative 5 A thiophene derivative 5 (TP5) represented by the formula (X3) was synthesized by the following method.

Under a nitrogen atmosphere, 1.50 g of benzodithiophene (manufactured by Tokyo Chemical Industry Co., Ltd.) was placed in a reaction vessel, 50 mL of tetrahydrofuran (THF) was added, and then cooled to -78 ° C. Thereto, 19.2 mL of n-butyllithium n-hexane solution (concentration 1.64 mol / L, 4 eq) was added dropwise, followed by stirring for 1.5 hours. Further, 8.6 mL (4 eq) of tri-n-butylchlorostannane was added dropwise thereto, and after further reaction at −78 ° C. for 1 hour, the cooling bath was removed and the temperature was raised to room temperature. After reaching room temperature, the solvent was distilled off under reduced pressure, and the precipitate in the resulting slurry was filtered and dried to obtain 11.84 g of a mixture containing the desired benzodithiophene bisstannyl compound. Further, no further purification was carried out, and the purity was calculated assuming that the yield of this step was 100% (theoretical yield 6.07 g) (6.07 / 11.84 × 100 = 51.3%). Used as raw material.
Subsequently, under a nitrogen atmosphere, 5.92 g of the mixture containing the obtained benzodithiophene bisstannyl compound, 2.15 g (2.2 eq) of 2-bromo-3-n-hexylthiophene (manufactured by Tokyo Chemical Industry Co., Ltd.) , 25 mL of toluene and 0.230 g (5 mol%) of Pd (PPh ₃ ) ₄ were placed in a reaction vessel and stirred for 4.5 hours under heating and refluxing conditions. After allowing to cool to room temperature, chloroform and ion-exchanged water were added for liquid separation. The solvent of the obtained organic layer was distilled off under reduced pressure, methanol was added to the obtained yellow slurry, and insoluble matter was filtered off. The filtrate was subjected to activated carbon treatment, the solvent was distilled off under reduced pressure, ethanol and toluene were added to the residue, and the mixture was stirred under heating under reflux. After confirming complete dissolution, the mixture was allowed to cool to room temperature. After stirring overnight at room temperature, it was filtered and dried to obtain TP5 (yield 1.40 g, 2-step yield 68%). The measurement results of ¹ H-NMR and TOF-MS are shown below.
¹ H-NMR (300 MHz, CDCl ₃ ) δ [ppm]: 8.16 (s, 2H), 7.34 (s, 2H), 7.26 (d, J = 5.1 Hz, 2H), 6.98 (d, J = 5.1 Hz, 2H), 2.87 (t, J = 8.0Hz, 4H), 1.63-1.74 (m, 4H), 1.30-1.42 (m, 12H), 0.88 (t, J = 6.6Hz, 6H).
MALDI-TOF-MS m / Z found: 521.87 ([M] ⁺ calcd: 522.15)

[Synthesis Example 5] Synthesis of aniline derivative 1 (AN1) Aniline derivative 1 (AN1) represented by the formula (X5) was synthesized by the following method.

N, N′-diphenylbenzidine (2.00 g), 4-bromo-N, N-diphenylaniline (4.25 g), Pd (dba) ₂ 68.4 mg, and ^t BuONa (1.49 g) were placed in a reaction vessel and purged with nitrogen. , toluene 20mL and separately prepared P a ^(t Bu) ₃ in toluene 1.0 mL (concentration 47.2 g / L) was added, and stirred for 7 hours at 50 ° C., and reacted. After cooling to room temperature, the reaction solution was filtered, and the resulting filtrate was washed with ion-exchanged water. Filtration was performed again, and the obtained filtrate was dried to obtain AN1 (yield 4.46 g, yield 91%). The measurement results of TOF-MS are shown below.
MALDI-TOF-MS m / Z found: 822.25 ([M] ⁺ calcd: 822.37)

[Synthesis Example 6] Synthesis of aniline derivative 2 (AN2) Aniline derivative 2 (AN2) represented by the formula (X6) was synthesized by the following method.

N, N'-diphenyl benzidine 1.00 g, 3- bromo-9-ethyl carbazole _{1.96g, Pd (dba) 2 34.7mg} , and ^t BuONa0.860G placed in a reaction vessel, after nitrogen substitution, toluene 15mL and separately prepared P ^(t Bu) ₃ in toluene 0.51mL (concentration 47.2 g / L) was added, and stirred for 6.5 hours at 50 ° C., and reacted. After cooling to room temperature, toluene and saturated brine were added to separate the layers. The obtained organic layer was dried over Na ₂ SO ₄ , activated carbon was added, and the mixture was stirred at room temperature for 30 minutes. The activated carbon was removed by filtration and concentration was performed. The obtained concentrated liquid was dropped into a MeOH-AcOEt mixed solvent and stirred at room temperature. The slurry solution was filtered, dried, and then washed with a toluene-methanol mixed solvent. After filtration, the obtained powder was dried to obtain AN2 (yield 1.87 g, yield 87%). The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (300 MHz, DMSO-d6) δ [ppm]: 8.10 (d, J = 7.8 Hz, 2H), 7.99 (d, J = 1.8 Hz, 2H), 7.59-7.66 (m, 4H), 7.42 -7.51 (m, 6H), 7.23-7.29 (m, 7H), 6.94-7.18 (m, 11H).

[2] Preparation of charge transporting varnish [Example 1-1]
3,3 ″ ′-dihexyl-2,2 ′: 5 ′, 2 ″: 5 ″, 2 ′ ″-quaterthiophene (manufactured by Sigma-Aldrich Co. LLC., Hereinafter referred to as TP1) 1050 g, phosphotungstic acid (PTA, manufactured by Kanto Chemical Co., Ltd.) 0.250 g and F4TCNQ (manufactured by Tokyo Chemical Industry Co., Ltd.) 0.045 g were subjected to 1,3-dimethyl-2-imidazolidinone under a nitrogen atmosphere. (DMI) Dissolved in 3.2 g. To the obtained solution, 4.9 g of cyclohexanol (CHA) and 1.6 g of propylene glycol (PG) were added and stirred to prepare a charge transporting varnish.

[Example 1-2]
0.052 g of TP1, 0.258 g of PTA and 0.031 g of F4TCNQ were dissolved in 2 g of DMI under a nitrogen atmosphere. To the resulting solution, 2 g of CHA and 6 g of diethylene glycol dimethyl ether (Diglyme) were added and stirred to prepare a charge transporting varnish.

[Example 1-3]
0.052 g of TP1, 0.258 g of PTA and 0.031 g of F4TCNQ were dissolved in 2 g of DMI under a nitrogen atmosphere. To the obtained solution, 8 g of propylene glycol monomethyl ether (PGME) was added and stirred to prepare a charge transporting varnish.

[Example 1-4]
0.052 g of TP1, 0.258 g of PTA and 0.031 g of F4TCNQ were dissolved in 2 g of DMI under a nitrogen atmosphere. To the obtained solution, 8 g of PGME was added and stirred, 0.031 g of pentafluorophenyltriethoxysilane was added thereto, and further stirred to prepare a charge transporting varnish.

[Example 1-5]
0.017 g of TP1, 0.083 g of PTA and 0.010 g of F4TCNQ were dissolved in 0.98 g of DMI under a nitrogen atmosphere. To the obtained solution, 0.49 g of diethylene glycol monomethyl ether (DEGME) and 3.43 g of PGME were added and stirred, then 0.001 g of 3,3,3-trifluoropropyltrimethoxysilane and 0.009 g of phenyltrimethoxysilane. And further stirred to prepare a charge transport varnish.

[Example 1-6]
0.052 g of TP2, 0.258 g of PTA and 0.031 g of F4TCNQ were dissolved in 2 g of DMI under a nitrogen atmosphere. To the resulting solution, 2 g of CHA and 6 g of Diglyme were added and stirred to prepare a charge transporting varnish.

[Example 1-7]
0.062g of TP3, 0.309g of PTA and 0.026g of F4TCNQ were dissolved in 3.6g of DMI under nitrogen atmosphere. To the resulting solution, 2.4 g of 1,3-butanediol and 6.0 g of Diglyme were added and stirred to prepare a charge transporting varnish.

[Example 1-8]
TP4 0.034 g, PTA 0.170 g and F4TCNQ 0.020 g were dissolved in DMI 2 g under nitrogen atmosphere. 1 g of DEGME and 7 g of PGME are added to the resulting solution and stirred. Then, 0.007 g of 3,3,3-trifluoropropyltrimethoxysilane and 0.014 g of phenyltrimethoxysilane are added and stirred to obtain a charge transporting varnish. Prepared.

[Example 1-9]
0.034 g of TP5, 0.170 g of PTA and 0.031 g of F4TCNQ were dissolved in 2 g of DMI under a nitrogen atmosphere. 1 g of DEGME and 7 g of PGME are added to the resulting solution and stirred. Then, 0.007 g of 3,3,3-trifluoropropyltrimethoxysilane and 0.014 g of phenyltrimethoxysilane are added and stirred to obtain a charge transporting varnish. Prepared.

[Example 1-10]
AN1 0.046 g, PTA 0.202 g and F4TCNQ 0.156 g were dissolved in cyclohexanone (CHN) 20 g under nitrogen atmosphere. To the resulting solution, 0.007 g of 3,3,3-trifluoropropyltrimethoxysilane and 0.014 g of phenyltrimethoxysilane were added and stirred to prepare a charge transporting varnish.

[Example 1-11]
AN2 0.042g, PTA 0.202g and F4TCNQ 0.160g were dissolved in CHN 20g under nitrogen atmosphere. To the resulting solution, 0.007 g of 3,3,3-trifluoropropyltrimethoxysilane and 0.014 g of phenyltrimethoxysilane were added and stirred to prepare a charge transporting varnish.

[Comparative Example 1-1]
0.124 g of TP1 and 0.247 g of PTA were dissolved in 4 g of DMI under a nitrogen atmosphere. To the obtained solution, 6 g of CHA and 2 g of PG were added and stirred to prepare a charge transporting varnish.

[Comparative Example 1-2]
An attempt was made to prepare a charge transporting varnish using 0.050 g of TP1, 0.250 g of PTA and 0.045 g of tetracyanoquinodimethane, and 3.2 g of DMI, 4.9 g of CHA and 1.6 g of PG under a nitrogen atmosphere. However, the solid content did not dissolve, and a uniform varnish that could give a thin film that could be used for an organic EL device could not be obtained.

[3] Manufacture and characteristic evaluation of organic EL element [Example 2-1]
The varnish obtained in Example 1-1 was applied to an ITO substrate using a spin coater, then dried at 50 ° C. for 5 minutes, and further baked at 150 ° C. for 10 minutes in an air atmosphere. A uniform thin film of 30 nm was formed. As the ITO substrate, a glass substrate of 25 mm × 25 mm × 0.7 t with indium tin oxide (ITO) patterned to a thickness of 150 nm on the surface is used, and an O ₂ plasma cleaning device (150 W, 30 seconds) before use. To remove impurities on the surface.
Next, a thin film of α-NPD, Alq ₃ , lithium fluoride, and aluminum is sequentially laminated on the ITO substrate on which the thin film is formed using a vapor deposition apparatus (vacuum degree: 1.0 × 10 ⁻⁵ Pa), and organic EL An element was obtained. At this time, the deposition rate is 0.2 nm / second for α-NPD, Alq ₃ and aluminum, and 0.02 nm / second for lithium fluoride, and the film thickness is 30 nm, 40 nm, and 0.0 nm, respectively. It was 5 nm and 120 nm.
In addition, in order to prevent the characteristic deterioration by the influence of oxygen in the air, water, etc., after sealing the organic EL element with the sealing substrate, the characteristic was evaluated. Sealing was performed according to the following procedure. In a nitrogen atmosphere with an oxygen concentration of 2 ppm or less and a dew point of −85 ° C. or less, the organic EL element was placed between the sealing substrates, and the sealing substrate was bonded with an adhesive (XNR5516Z-B1 manufactured by Nagase ChemteX Corporation). . At this time, a water catching agent (HD-071010W-40 manufactured by Dynic Co., Ltd.) was placed in the sealing substrate together with the organic EL element. The bonded sealing substrate 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 2-7]
An organic EL device was produced in the same manner as in Example 2-1, except that the varnish obtained in Examples 1-2 to 1-7 was used instead of the varnish obtained in Example 1-1. did.

[Examples 2-8 to 2-9]
Instead of the varnish obtained in Example 1-1, the varnish obtained in Examples 1-8 to 1-9 was used, respectively. An organic EL device was produced in the same manner as in Example 2-1.

[Comparative Example 2-1]
An organic EL device was produced in the same manner as in Example 2-1, except that the varnish obtained in Comparative Example 1-1 was used instead of the varnish obtained in Example 1-1.

[Example 2-10]
Instead of the varnish obtained in Example 1-1, the varnish obtained in Example 1-10 was used, and Alq ₃ was a 40 nm thin film using a vapor deposition apparatus (vacuum degree 1.0 × 10 ⁻⁵ Pa). As in Example 2-1, except that a thin film of CBP and Ir (PPy) _{3 and} a thin film of BAlq were sequentially formed using a vapor deposition apparatus (vacuum degree: 1.0 × 10 ⁻⁵ Pa). The organic EL element was produced by the method.
Incidentally, the thin film of CBP and Ir (PPy) ₃ is formed by co-evaporation of CBP and Ir (PPy) ₃ while controlling the evaporation rate so that the concentration of Ir (PPy) ₃ is 6%, the film The thickness was 40 nm. The deposition rate of the BAlq film thickness was 0.2 nm / second, and the film thickness was 20 nm.

[Example 2-11]
An organic EL device was produced in the same manner as in Example 2-10, except that the varnish obtained in Example 1-11 was used instead of the varnish obtained in Example 1-10.

  The brightness | luminance of the element of Examples 2-1 to 2-9 in the drive voltage 5V and the brightness | luminance of the element of Examples 2-10 to 2-11 in 0.4 mA of drive currents were measured, respectively. The results are shown in Tables 1 and 2.

  As shown in Tables 1 and 2, with the varnish of the present invention, an organic EL device having excellent luminance characteristics could be realized even when baked at a low temperature of less than 200 ° C.

The durability of the devices obtained in Examples 2-2 to 2-8 was evaluated. The luminance half-life (initial luminance 5,000 cd / m ² ) is shown in Table 3.

  As shown in Table 3, the organic EL device of the present invention was excellent in durability.

Claims (11)

  A charge transporting varnish comprising a charge transporting substance, a dopant and an organic solvent, wherein the dopant comprises a heteropolyacid and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. A charge transporting varnish characterized by that.   The charge transporting varnish according to claim 1, wherein the halogenated tetracyanoquinodimethane comprises tetracyanoquinodimethane fluoride.   The charge transporting varnish according to claim 1 or 2, wherein the heteropolyacid contains phosphotungstic acid.   The charge transporting varnish according to any one of claims 1 to 3, wherein the charge transporting substance is an aniline derivative or a thiophene derivative.   A charge transporting thin film produced using the charge transporting varnish according to claim 1.   An organic electroluminescence device comprising the charge transporting thin film according to claim 5.   The organic electroluminescence device according to claim 6, wherein the charge transporting thin film is a hole injection layer or a hole transport layer.   A method for 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 firing the substrate at a temperature of less than 200 ° C.   A method for producing an organic electroluminescent device, comprising using the charge transporting thin film according to claim 5.   A charge transport material comprising a charge transport material and a dopant, wherein the dopant includes a heteropolyacid and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. A charge transporting material. A method for planarizing a charge transporting thin film using at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone,
Use of a charge transporting varnish containing a charge transporting substance, a dopant and an organic solvent, wherein the dopant contains a heteropolyacid and at least one selected from halogenated tetracyanoquinodimethane and halogenated or cyanated benzoquinone. A method for planarizing a charge transporting thin film characterized by the following.