Fluorinated aryl sulfonic acid polymer compounds and their uses

Abstract

This fluorinated arylsulfonate polymer compound comprises repeating units represented by formula (1), and is suitable as a dopant substance for use in organic EL elements and the like. (In the formula, ArF represents a fluorinated arylene group, X represents O, S, NH, CONH or NHCO, and ArS represents an aryl group having, on a ring, at least one SO3R group (where R represents a hydrogen atom or an alkali metal atom)).

Description

[Technical Field]

[0001] This invention relates to fluorinated aryl sulfonic acid polymer compounds and their uses. [Background technology]

[0002] Organic electroluminescent (hereinafter referred to as organic EL) devices utilize organic functional films made of organic compounds as the light-emitting layer and charge injection layer. In particular, the hole injection layer is responsible for the transfer of charge between the anode and the hole transport layer or light-emitting layer, playing an important role in achieving low-voltage operation and high brightness of organic EL devices. Methods for forming hole injection layers are broadly classified into dry processes, such as vapor deposition, and wet processes, such as spin coating. Comparing these processes, wet processes can efficiently produce thin films with high flatness over large areas. Therefore, with the increasing size of organic EL displays, hole injection layers that can be formed by wet processes are desired, and there have been reports on technologies related to hole injection materials that can be deposited by wet processes (Patent Document 1).

[0003] In light of these circumstances, the applicant has been developing charge transport materials that can be applied to various wet processes and provide thin films that can achieve excellent EL device characteristics when applied to the hole injection layer of organic EL devices, as well as compounds suitable as charge transport substances and dopants that exhibit solubility in organic solvents used therein (see Patent Documents 2-6). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2008 / 032616 [Patent Document 2] International Publication No. 2008 / 129947 [Patent Document 3] International Publication No. 2006 / 025342 [Patent Document 4] International Publication No. 2010 / 058777 [Patent Document 5] International Publication No. 2005 / 000832 [Patent Document 6] International Publication No. 2009 / 096352 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Similar to the technologies described in the aforementioned patent documents that have been developed to date, the present invention aims to provide a fluorinated aryl sulfonic acid polymer compound suitable as a dopant material used in organic EL elements and the like. [Means for solving the problem]

[0006] As a result of diligent research to solve the above problems, the inventors have found that a thin film with excellent charge transport properties can be realized when a predetermined fluorinated aryl sulfonic acid polymer compound having a fluorinated arylene group and an aryl group containing at least one sulfo group or a salt thereof is used as a dopant material together with a charge transport material, and have completed the present invention.

[0007] In other words, the present invention is 1. A fluorinated aryl sulfonic acid polymer compound characterized by containing a repeating unit represented by the following formula (1), [ka] [In the formula, Ar F represents an arylene fluoride group, X represents O, S, NH, CONH, or NHCO, and Ar S This represents an aryl group having at least one SO3R group on the ring (where R represents a hydrogen atom or an alkali metal atom). 2. Furthermore, one fluorinated aryl sulfonic acid polymer compound containing a repeating unit represented by the following formula (2), [ka] (In the formula, R' represents a monovalent organic group.) 3. The fluorinated aryl sulfonic acid polymer compound in which R' is an aryl fluoride group, 4. The aforementioned Ar F However, one of the fluorinated aryl sulfonic acid polymer compounds 1 to 3, which is a perfluoroarylene group, 5. The aforementioned Ar F However, the fluorinated aryl sulfonic acid polymer compound has a tetrafluorophenylene group, 6. The aforementioned Ar S However, any of the fluorinated aryl sulfonic acid polymer compounds 1 to 5, which are aryl groups having two or more SO3R groups on the ring, 7. The aforementioned Ar S However, 6 fluorinated aryl sulfonic acid polymer compounds, which are naphthyl groups having two or more SO3R groups on the ring, 8. The aforementioned X is one of the fluorinated aryl sulfonic acid polymer compounds 1 to 7, where X is O. 9. A dopant substance consisting of any of the fluorinated aryl sulfonic acid polymer compounds from 1 to 8, 10. A charge-transporting varnish containing a charge-transporting substance, nine dopant substances, and a solvent. 11. The charge-transporting varnish of 10, wherein the charge-transporting substance is an arylamine derivative or a thiophene derivative. 12. Charge-transporting thin film obtained from charge-transporting varnish 10 or 11, 13. Electronic device equipped with 12 charge-transporting thin films, 14. Organic electroluminescent device equipped with 12 charge-transporting thin films, 15. The charge-transporting thin film is a hole injection layer or a hole transport layer in 14 organic electroluminescent elements. To provide. [Effects of the Invention]

[0008] The fluorinated arylsulfonic acid polymer compound of the present invention can be used as a dopant material together with a charge transport material to provide a charge transport thin film having excellent electrical properties. An organic EL device provided with such a thin film exhibits good properties and is particularly excellent in life performance. In addition, a thin film containing the fluorinated arylsulfonic acid polymer compound of the present invention has good upper layer coating properties. The fluorinated arylsulfonic acid polymer compound of the present invention having such characteristics can be suitably used as a dopant material in the production of thin films for electronic devices such as organic EL devices, particularly thin films for organic EL displays.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, the present invention will be described in more detail. [1] Fluorinated arylsulfonic acid polymer compound The fluorinated arylsulfonic acid polymer compound according to the present invention is characterized by containing a repeating unit represented by the following formula (1).

[0010]

Chemical formula

[0011] In formula (1), Ar F represents a fluorinated arylene group. The fluorinated arylene group of Ar F is not particularly limited as long as at least one hydrogen atom on the arylene group is substituted with a fluorine atom, but it is preferable that at least one of the remaining hydrogen atoms is substituted with an electron-withdrawing group other than a sulfo group. Examples of the electron-withdrawing group include halogen atoms such as fluorine atom, chlorine atom, bromine atom, and iodine atom; nitro group; cyano group; acyl group; carboxy group; carboxylic acid ester group; acyl groups such as formyl group and acetyl group. In particular, the fluorinated arylene group of Ar F is preferably an arylene group substituted with two or more fluorine atoms, and more preferably a perfluoroarylene group.

[0012] Ar F There are no particular restrictions on the number of carbon atoms in the arylene group that constitutes the arylene, but a number of carbon atoms of 6 to 20 is preferred, and a number of carbon atoms of 6 to 16 is more preferred. Specific examples include 1,4-phenylene, 1,3-phenylene, 1,2-phenylene, 1,5-naphthylene, 1,7-naphthylene, 1,8-naphthylene, 2,6-naphthylene, 2,7-naphthylene, 4,4'-biphenylene, anthracenyl group, etc., but a phenylene group is preferred, and a 1,4-phenylene group is more preferred. Therefore, Ar F A tetrafluorophenylene group is preferred, and a 2,3,5,6-tetrafluoro-1,4-phenylene group is more preferred.

[0013] X represents O, S, NH, CONH, or NHCO, with O and S being preferred, and O being more preferred.

[0014] Suitable fluorinated aryl sulfonic acid polymer compounds of the present invention include those represented by the following formula (1-1).

[0015] [ka] (In the formula, n1 represents an integer between 1 and 4.)

[0016] More suitable fluorinated aryl sulfonic acid polymer compounds include those represented by the following formulas (1-2).

[0017] [ka] (In the formula, n1 represents an integer between 1 and 4.) Even more suitable fluorinated aryl sulfonic acid polymer compounds include those represented by the following formulas (1-3).

[0018] [ka]

[0019] Ar S represents an aryl group having at least one SO3R group on the ring, where R represents a hydrogen atom or an alkali metal atom such as Li, Na, or K, but a hydrogen atom is preferred. Ar S There are no particular restrictions on the number of carbon atoms in the aryl group that constitutes the aryl group, but a number of carbon atoms of 6 to 30 is preferred, a number of carbon atoms of 6 to 20 is more preferred, and a number of carbon atoms of 6 to 12 is even more preferred. Specific examples include phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, and 9-phenanthryl groups, but the naphthyl group is preferred, and the 1-naphthyl group is more preferred. Also, Ar S The number of SO3R groups present may be one or more, but preferably 2 to 4, and more preferably 2. Suitable Ar S For example, the following formula (Ar S -1)~(Ar S Examples include those shown in -6).

[0020] [ka] (In the formula, R has the same meaning as above. n represents an integer between 2 and 4.)

[0021] [ka] (In the formula, R has the same meaning as above.)

[0022] [ka] (In the formula, R has the same meaning as above.)

[0023] [ka] (In the formula, R has the same meaning as above.)

[0024] The fluorinated aryl sulfonic acid polymer compound of the present invention may be a polymer containing only the repeating unit represented by formula (1) above, but a polymer containing a repeating unit represented by formula (2) below is preferred from the viewpoint of improving solubility in organic solvents.

[0025] [ka]

[0026] In equation (2), R' represents a monovalent organic group. Examples of monovalent organic groups include monovalent hydrocarbon groups, heteroaryl groups, and -COOR" groups (where R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms). There are no particular restrictions on the number of carbon atoms in the monovalent hydrocarbon group, but 1 to 20 carbon atoms are preferred, 6 to 20 carbon atoms are more preferred, and 6 to 10 carbon atoms are even more preferred. Specific examples include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, cyclopentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; and aryl groups such as phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, and 9-phenanthryl groups.

[0027] Specific examples of heteroaryl groups include heteroaryl groups with 2 to 20 carbon atoms, such as 2-thienyl, 3-thienyl, 2-furanyl, 3-furanyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 3-isoxazolyl, 4-isoxazolyl, 5-isoxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, 2-imidazolyl, 4-imidazolyl, 2-pyridyl, 3-pyridyl, and 4-pyridyl groups.

[0028] Examples of alkyl groups with 1 to 10 carbon atoms in R'' include those similar to the groups exemplified above, but alkyl groups with 1 to 5 carbon atoms are preferred.

[0029] Furthermore, the above-mentioned monovalent hydrocarbon group, heteroaryl group, and C1-C10 alkyl group of R'' may have some or all of their hydrogen atoms substituted with substituents. Examples of such substituents include halogen atoms, cyano groups, nitro groups, carboxyl groups, sulfo groups, and hydroxyl groups. Examples of halogen atoms are the same as those exemplified above.

[0030] Among these, considering the improvement of the device characteristics and lifetime characteristics of organic EL elements obtained using the fluorinated aryl sulfonic acid polymer compound of the present invention as a dopant material, R' is preferably an aryl group substituted with a halogen atom, more preferably an aryl fluoride group, and even more preferably a perfluoroaryl group. In particular, phenyl groups substituted with halogen atoms are preferred, phenyl fluoride groups are more preferred, and perfluorophenyl groups are even more preferred.

[0031] When the fluorinated aryl sulfonic acid polymer compound of the present invention contains repeating units represented by formula (2), the content ratio of the units of formula (1) to the units of formula (2) is not particularly limited. However, considering the improvement of the device characteristics when used as a dopant material, a molar ratio of formula (1):formula (2) = 10:1 to 1:10 is preferred, 5:1 to 1:5 is more preferred, 3:1 to 1:3 is even more preferred, and 1:1 is even more preferred.

[0032] The molecular weight of the fluorinated aryl sulfonic acid polymer compound of the present invention is not particularly limited, but from the viewpoint of improving heat resistance and ensuring solubility in solvents, a weight-average molecular weight Mw of 1000 to 50000 is preferred, 1500 to 10000 is more preferred, and 2000 to 10000 is even more preferred. Furthermore, the molecular weight distribution (Mw / Mn) is preferably 1 to 3, and more preferably 1 to 2. Note that this weight-average molecular weight was measured by gel permeation chromatography (GPC) using polyethylene oxide as the standard sample.

[0033] The fluorinated aryl sulfonic acid polymer compounds of the present invention can be obtained by polymerizing a monomer represented by the following formula (1A) and optionally a monomer represented by the following formula (2A) in the presence of a solvent and a radical polymerization initiator by a known radical polymerization method. In this case, two or more monomers represented by formula (1A) may be used in combination, and two or more monomers represented by formula (2A) may be used in combination.

[0034] [ka] (In the formula, Ar F Ar S , X and R 1 (This expresses the same meaning as above.)

[0035] Known compounds such as radical thermal polymerization initiators and radical photopolymerization initiators can be used as radical polymerization initiators. Radical thermal polymerization initiators are compounds that generate radicals when heated above their decomposition temperature. Examples of such radical thermal polymerization initiators include ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), diacyl peroxides (acetyl peroxide, benzoyl peroxide, etc.), hydroperoxides (hydrogen peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyketals (dibutyl peroxycyclohexane, etc.), alkyl peresters (tert-butyl peroxyneodecanoate, tert-butyl peroxypivalate, tert-amyl peroxy2-ethylcyclohexanoate, etc.), persulfates (potassium persulfate, sodium persulfate, ammonium persulfate, etc.), and azo compounds (azobisisobutyronitrile, 2,2'-di(2-hydroxyethyl)azobisisobutyronitrile, etc.). Radical thermal polymerization initiators may be used individually or in combination of two or more.

[0036] The radical photopolymerization initiator is not particularly limited as long as it is a compound that initiates radical polymerization by light irradiation. Examples of such radical photopolymerization initiators include benzophenone, Michla's ketone, 4,4'-bis(diethylamino)benzophenone, xanthone, thioxanthone, isopropylxanthone, 2,4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexylphenyl ketone, isopropylbenzoin ether, isobutylbenzoin ether, 2 ,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzantrone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 4-ethyl dimethylaminobenzoate, 4-isoamyl dimethylaminobenzoate, 4,4'-di(tert-butylperoxycarbonyl)benzophenone, 3,4,4'-tri(tert-butylperoxy Carbonyl)benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-pentyloxy Styryl)-4,6-bis(trichloromethyl)-s-triazine, 4-[pN,N-di(ethoxycarbonylmethyl)]-2,6-di(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(4'-methoxyphenyl)-s-triazine, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzthiazole, 2-mercaptobenzothiazole, 3,3'-Carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'bis(2 ,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-dimethylaminopropionyl)carbazole, 3,6-bis(2-methyl-2-morpholinopropionyl)-9-n-dodecylcarbazole, 1-hydroxycyclohexylphenyl ketone, Bis(5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)-phenyl)titanium, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(t-hexylperoxycarbonyl)benzophenone, 3,3'-di(methoxycarbonyl)-4,4'-di(t-butylperoxycarbonyl)benzophenone, 3,4'- Examples include di(methoxycarbonyl)-4,3'-di(t-butylperoxycarbonyl)benzophenone, 4,4'-di(methoxycarbonyl)-3,3'-di(t-butylperoxycarbonyl)benzophenone, 2-(3-methyl-3H-benzothiazole-2-ylidene)-1-naphthalene-2-yl-ethanone, and 2-(3-methyl-1,3-benzothiazole-2(3H)-ylidene)-1-(2-benzoyl)ethanone. The radical photopolymerization initiator may be used alone or in combination of two or more.

[0037] The solvent used in the polymerization reaction is not particularly limited as long as it dissolves the resulting polymer. Specific examples include water; N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methyl-ε-caprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ-butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl Dipropyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, 1,Examples of organic solvents include 4-dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol acetate monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 3-methoxy-N,N-dimethylpropanamide, 3-ethoxy-N,N-dimethylpropanamide, and 3-butoxy-N,N-dimethylpropanamide.

[0038] The polymerization temperature during radical polymerization can be selected from any temperature between 30 and 150°C, but is preferably in the range of 50 to 100°C.

[0039] The monomer of formula (1A) can be produced by known methods disclosed in Patent Document 7, for example, by reacting an aryl sulfonate having a hydroxyl group with a fluoroaryl compound in the presence of a base.

[0040] [2] Charge transport varnish The charge-transporting varnish of the present invention comprises a dopant substance consisting of the above-mentioned fluorinated aryl sulfonic acid polymer compound, a charge-transporting substance, and a solvent. In this invention, charge transport is synonymous with conductivity and hole transport. A charge transport varnish may be one that possesses charge transport properties itself, or the solid film obtained therefrom may possess charge transport properties.

[0041] The charge-transporting material is not particularly limited, and can be appropriately selected from charge-transporting compounds, charge-transporting oligomers, charge-transporting polymers, etc., used in fields such as organic LEDs. Specific examples include various charge-transporting compounds such as oligoaniline derivatives, N,N'-diarylbenzidine derivatives, N,N,N',N'-tetraarylbenzidine derivatives, and other arylamine derivatives; thiophene derivatives such as oligothiophene derivatives, thienothiophene derivatives, and thienobenzothiophene derivatives; and pyrrole derivatives such as oligopyrrole, as well as charge-transporting polymers such as charge-transporting oligomers, polythiophene derivatives, polyaniline derivatives, and polypyrrole derivatives. Among these, polythiophene derivatives and arylamine derivatives are preferred.

[0042] Furthermore, charge-transporting compounds (low molecular weight compounds) or charge-transporting oligomers, such as the arylamine compounds represented by formula (H2) or (H3) described later, are preferably monodisperse (i.e., have a molecular weight distribution of 1) from the viewpoint of producing highly flat thin films. In this case, the molecular weight of the charge-transporting substance is usually around 200 to 9,000 from the viewpoint of preparing a uniform varnish that gives a highly flat thin film, but from the viewpoint of obtaining a thin film with better charge transport properties, it is preferably 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 better reproducibility, it is preferably 8,000 or less, more preferably 7,000 or less, even more preferably 6,000 or less, and still more preferably 5,000 or less.

[0043] Examples of charge-transporting materials include those described in Japanese Patent Publication No. 2002-151272, International Publication No. 2004 / 105446, International Publication No. 2005 / 043962, International Publication No. 2008 / 032617, International Publication No. 2008 / 032616, International Publication No. 2013 / 042623, International Publication No. 2014 / 141998, and International Publication No. 2014 / 185208. Examples include those disclosed in International Publication Nos. 2015 / 050253, 2015 / 137391, 2015 / 137395, 2015 / 146912, 2015 / 146965, 2016 / 190326, 2016 / 136544, 2016 / 204079, and others.

[0044] In one preferred embodiment, the charge-transporting substance is a polythiophene derivative or an amine adduct thereof containing a repeating unit represented by formula (H1).

[0045] [ka]

[0046] In the formula, R 1 'and R 2 ' is independently a hydrogen atom, a C1-C40 alkyl group, a C1-C40 fluoroalkyl group, a C1-C40 alkoxy group, a C1-C40 fluoroalkoxy group, a C6-C20 aryloxy group, and -O-[ZO] h -R e , or a sulfo group, or R 1 and R 2 The -OYO- is formed by the bonding of the following: Y is an alkylene group having 1 to 40 carbon atoms, which may contain an ether bond and may be substituted with a sulfo group; Z is an alkylene group having 1 to 40 carbon atoms, which may be substituted with a halogen atom; p is an integer of 1 or more; R e These are a hydrogen atom, an alkyl group having 1 to 40 carbon atoms, a fluoroalkyl group having 1 to 40 carbon atoms, or an aryl group having 6 to 20 carbon atoms.

[0047] The alkyl group having 1 to 40 carbon atoms may be linear, branched, or cyclic. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosanyl, behenyl, triacontyl, and tetracontyl groups. In the present invention, alkyl groups having 1 to 18 carbon atoms are preferred, and alkyl groups having 1 to 8 carbon atoms are more preferred.

[0048] The fluoroalkyl groups having 1 to 40 carbon atoms are not particularly limited as long as they are alkyl groups having 1 to 40 carbon atoms in which at least one hydrogen atom on a carbon atom is replaced by a fluorine atom. Specific examples include fluoromethyl, difluoromethyl, perfluoromethyl, 1-fluoroethyl, 2-fluoroethyl, 1,2-difluoroethyl, 1,1-difluoroethyl, 2,2-difluoroethyl, 1,1,2-trifluoroethyl, 1,2,2-trifluoroethyl, 2,2,2-trifluoroethyl, 1,1,2,2-tetrafluoroethyl, 1,2,2,2-tetrafluoroethyl, perfluoroethyl, 1-fluoropropyl, 2-fluoropropyl, 3-fluoropropyl, 1,1-difluoropropyl, 1,2-difluoropropyl, 1,3-difluoropropyl, 2,2-difluoropropyl, 2,3-difluoropropyl, 3,3-difluoropropyl, and 1,1,2-trifluoropropyl. Examples include 1,1,3-trifluoropropyl, 1,2,3-trifluoropropyl, 1,3,3-trifluoropropyl, 2,2,3-trifluoropropyl, 2,3,3-trifluoropropyl, 3,3,3-trifluoropropyl, 1,1,2,2-tetrafluoropropyl, 1,1,2,3-tetrafluoropropyl, 1,2,2,3-tetrafluoropropyl, 1,3,3,3-tetrafluoropropyl, 2,2,3,3-tetrafluoropropyl, 2,3,3,3-tetrafluoropropyl, 1,1,2,2,3-pentafluoropropyl, 1,2,2,3,3-pentafluoropropyl, 1,1,3,3,3-pentafluoropropyl, 1,2,3,3,3-pentafluoropropyl, 2,2,3,3,3-pentafluoropropyl, perfluoropropyl, perfluorobutyl, perfluoropentyl, perfluorohexyl, perfluoroheptyl, and perfluorooctyl groups.

[0049] The alkoxy group having 1 to 40 carbon atoms may have a linear, branched, or cyclic alkyl group. Specific examples include methoxy, ethoxy, n-propoxy, i-propoxy, c-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, n-hexoxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, n-undecyloxy, n-dodecyloxy, n-tridecyloxy, n-tetradecyloxy, n-pentadecyloxy, n-hexadecyloxy, n-heptadecyloxy, n-octadecyloxy, n-nonadecyloxy, and n-eicosanyloxy groups.

[0050] The fluoroalkoxy groups having 1 to 40 carbon atoms are not particularly limited as long as they are alkoxy groups having 1 to 40 carbon atoms in which at least one hydrogen atom on a carbon atom is replaced by a fluorine atom. Specific examples include fluoromethoxy, difluoromethoxy, perfluoromethoxy, 1-fluoroethoxy, 2-fluoroethoxy, 1,2-difluoroethoxy, 1,1-difluoroethoxy, 2,2-difluoroethoxy, 1,1,2-trifluoroethoxy, 1,2,2-trifluoroethoxy, 2,2,2-trifluoroethoxy, 1,1,2,2-tetrafluoroethoxy, 1,2,2,2-tetrafluoroethoxy, perfluoroethoxy, 1-fluoropropoxy, 2-fluoropropoxy, 3-fluoropropoxy, 1,1-difluoropropoxy, 1,2-difluoropropoxy, 1,3-difluoropropoxy, 2,2-difluoropropoxy, 2,3-difluoropropoxy, 3,3-difluoropropoxy, 1,1,2-trifluoropropoxy, 1,1,3-trifluoropropoxy, 1,2,3-trifluoropropoxy, 1,3,3-trifluoropropoxy, 2,2,3-trifluoropropoxy, 2,3,3-trifluoropropoxy, 3,3,3-trifluoropropoxy, 1,1,2,2-tetrafluoropropoxy, 1,1,2,3-tetrafluoropropoxy, 1,2,2,3-tetrafluoropropoxy Examples include xy, 1,3,3,3-tetrafluoropropoxy, 2,2,3,3-tetrafluoropropoxy, 2,3,3,3-tetrafluoropropoxy, 1,1,2,2,3-pentafluoropropoxy, 1,2,2,3,3-pentafluoropropoxy, 1,1,3,3,3-pentafluoropropoxy, 1,2,3,3,3-pentafluoropropoxy, 2,2,3,3,3-pentafluoropropoxy, and perfluoropropoxy groups.

[0051] Alkylene groups having 1 to 40 carbon atoms can be linear, branched, or cyclic. Specific examples include methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, nonamethylene, decylene, undecylene, dodecylene, tridecylene, tetradecylene, pentadecylene, hexadecylene, heptadecylene, octadecylene, nonadecylene, and eicosanylene groups.

[0052] Specific examples of aryl groups having 6 to 20 carbon atoms include phenyl, tolyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, and 9-phenanthryl groups, with phenyl, tolyl, and naphthyl groups being preferred. Specific examples of aryloxy groups with 6 to 20 carbon atoms include phenoxy, anthracenox, naphthoxy, phenantrenoxy, and fluorenoxy groups. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine.

[0053] In the above equation (1), R 1 and R 2 Each of these independently consists of a hydrogen atom, a fluoroalkyl group having 1 to 40 carbon atoms, an alkoxy group having 1 to 40 carbon atoms, and -O[C(R a R b )-C(R c R d )-O] h -R e , -OR f , or a sulfo group, or R 1 and R 2 -OYO- formed by the bonding of these elements is preferred. R a ~R d Each of these independently represents a hydrogen atom, an alkyl group having 1 to 40 carbon atoms, a fluoroalkyl group having 1 to 40 carbon atoms, or an aryl group having 6 to 20 carbon atoms. Specific examples of these groups are the same as those listed above. Among them, R a ~R d Each of these is preferably a hydrogen atom, a C1-C8 alkyl group, a C1-C8 fluoroalkyl group, or a phenyl group. R e This group is a hydrogen atom, a C1-C8 alkyl group, a C1-C8 fluoroalkyl group, or a phenyl group, but a hydrogen atom, a methyl group, a propyl group, or a butyl group is preferred. h is preferably an integer between 1 and 5, and more preferably 1, 2, or 3.

[0054] R f The group is a hydrogen atom, an alkyl group having 1 to 40 carbon atoms, a fluoroalkyl group having 1 to 40 carbon atoms, or an aryl group having 6 to 20 carbon atoms, but a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a fluoroalkyl group having 1 to 8 carbon atoms, or a phenyl group is preferred, and -CH2CF3 is more preferred.

[0055] The above R 1 ' is preferably a hydrogen atom or a sulfo group, more preferably a sulfo group, and R 2 ' is preferably an alkoxy group having 1 to 40 carbon atoms or -O-[ZO] h -R e , more preferably -O[C(R a R b )-C(R c R d )-O] h -R e OR f , more preferably -O[C(R a R b )-C(R c R d )-O] h -R e -O-CH2CH2-O-CH2CH2-O-CH3, -O-CH2CH2-O-CH2CH2-OH or -O-CH2CH2-OH, or R 1 and R 2 -OYO- is formed when these elements combine with each other.

[0056] For example, in the above polythiophene derivative according to a preferred embodiment of the present invention, R 1 ’ is a sulfo group, and R 2 ’ contains a repeating unit other than a sulfo group, or R 1 and R 2 ’ contains a repeating unit which is -O-Y-O- formed by bonding. Preferably, in the above polythiophene derivative, R 1 is a sulfo group, and R 2 ’ contains a repeating unit which is an alkoxy group having 1 to 40 carbon atoms or -O-[Z-O] h -R e or R 1 ’ and R 2 ’ contains a repeating unit which is -O-Y-O- formed by bonding. More preferably, in the above polythiophene derivative, R 1 ’ is a sulfo group, and R 2 ’ is -O[C(R a R b )-C(R c R d )-O] h -R e or -OR f and contains a repeating unit. Even more preferably, in the above polythiophene derivative, R 1 ’ is a sulfo group, and R 2 ’ is -O[C(R a R b )-C(R c R d )-O] h -R e and contains a repeating unit, or R 1 ’ and R 2 ’ contains a repeating unit which is -O-Y-O- formed by bonding. Even more preferably, in the above polythiophene derivative, R 1 ’ is a sulfo group, and R 2 4>’ contains a repeating unit which is -O-CH2CH2-O-CH2CH2-O-CH3, -O-CH2CH2-O-CH2CH2-OH, or -O-CH2CH2-OH, or R 1’ and R 2 ’ are combined with each other and include a repeating unit which is a group represented by the following formulas (Y1) and (Y2).

[0057] [Chemical formula]

[0058] Preferred specific examples of the above polythiophene derivative include, for example, polythiophene containing at least one kind of repeating unit represented by the following formulas (H1-1) to (H1-5).

[0059] [Chemical formula]

[0060] Moreover, preferred structures of the above polythiophene derivative include, for example, a polythiophene derivative having a structure represented by the following formula (H1a). In the following formula, each unit may be bonded randomly or as a block polymer.

[0061] [Chemical formula]

[0062] In the formula, a to d represent the molar ratio of each unit and satisfy 0 ≤ a ≤ 1, 0 ≤ b ≤ 1, 0 < a + b ≤ 1, 0 ≤ c < 1, 0 ≤ d < 1, and a + b + c + d = 1.

[0063] Furthermore, the above polythiophene derivative may be a homopolymer or a copolymer (including statistical, random, gradient, and block copolymers). As the polymer containing monomer A and monomer B, the block copolymer is, for example, an A-B diblock copolymer, an A-B-A triblock copolymer, and (AB) k-Includes multiblock copolymers. The polythiophene may also contain repeating units derived from other types of monomers (e.g., thienothiophene, selenofen, pyrrole, furan, tellophene, aniline, arylamine, and arylene (e.g., phenylene, phenylenevinylene, and fluorene, etc.)).

[0064] The content of the repeating unit represented by formula (H1) in the above polythiophene derivative is preferably more than 50 mol%, more preferably 80 mol% or more, even more preferably 90 mol% or more, even more preferably 95 mol% or more, and most preferably 100 mol% of the total repeating units contained in the polythiophene derivative.

[0065] The above polythiophene derivative may contain repeating units derived from impurities, depending on the purity of the starting monomer used for polymerization. The above term "homopolymer" means a polymer containing repeating units derived from one type of monomer, but may also contain repeating units derived from impurities. The above polythiophene derivative is preferably a polymer in which basically all repeating units are the repeating units represented by formula (H1), and more preferably a polymer containing at least one of the repeating units represented by formulas (H1-1) to (H1-5).

[0066] When the above-mentioned polythiophene derivative contains repeating units having sulfo groups, from the viewpoint of further improving solubility and dispersibility in organic solvents, the polythiophene derivative is preferably an amine adduct in which an amine compound is attached to at least a portion of the sulfo groups contained therein.

[0067] Amine compounds that can be used to form amine adducts include methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, s-butylamine, t-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, 2-ethylhexylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n Monoalkylamine compounds such as -octadecylamine, n-nonadecylamine, n-eicosanylamine; primary amine compounds such as aniline, tollamine, 1-naphthylamine, 2-naphthylamine, 1-anthrylamine, 2-anthrylamine, 9-anthrylamine, 1-phenanthrylamine, 2-phenanthrylamine, 3-phenanthrylamine, 4-phenanthrylamine, 9-phenanthrylamine, and other monoarylamine compounds; N-ethylmethylamine, N-methyl-n-propylamine, N-methylisopropylamine, N-methylmethyl N-methyl-n-butylamine, N-methyl-s-butylamine, N-methyl-t-butylamine, N-methylisobutylamine, diethylamine, N-ethyl-n-propylamine, N-ethylisopropylamine, N-ethyl-n-butylamine, N-ethyl-s-butylamine, N-ethyl-t-butylamine, dipropylamine, Nn-propylisopropylamine, Nn-propyl-n-butylamine, Nn-propyl-s-butylamine, diisopropylamine, Nn-butylisopropylamine, Nt-butylisopropylamine, di(n-butyl Dialkylamine compounds such as ethylamine, di(s-butyl)amine, diisobutylamine, aziridine (ethyleneimine), 2-methylaziridine (propyleneimine), 2,2-dimethylaziridine, azetidine (trimethyleneimine), 2-methylazetidine, pyrrolidine, 2-methylpyrrolidine, 3-methylpyrrolidine, 2,5-dimethylpyrrolidine, piperidine, 2,6-dimethylpiperidine, 3,5-dimethylpiperidine, 2,2,6,6-tetramethylpiperidine, hexamethyleneimine, heptamethyleneimine, octamethyleneimine, and other dialkylamine compounds;Diarylamine compounds such as diphenylamine, N-phenyl-1-naphthylamine, N-phenyl-2-naphthylamine, 1,1'-dinaphthylamine, 2,2'-dinaphthylamine, 1,2'-dinaphthylamine, carbazole, 7H-benzo[c]carbazole, 11H-benzo[a]carbazole, 7H-dibenzo[c,g]carbazole, 13H-dibenzo[a,i]carbazole; N-methylaniline, N-ethylaniline, Nn-propylaniline, N-I Secondary amine compounds such as alkylarylamine compounds including sopropylaniline, Nn-butylaniline, Ns-butylaniline, N-isobutylaniline, N-methyl-1-naphthylamine, N-ethyl-1-naphthylamine, Nn-propyl-1-naphthylamine, indoline, isoindoline, 1,2,3,4-tetrahydroquinoline, 1,2,3,4-tetrahydroisoquinoline, etc.; N,N-dimethylethylamine, N,N-dimethyl-n-propylamine, N,N- Trialkylamine compounds such as dimethylisopropylamine, N,N-dimethyl-n-butylamine, N,N-dimethyl-s-butylamine, N,N-dimethyl-t-butylamine, N,N-dimethylisobutylamine, N,N-diethylmethylamine, N-methyldi(n-propyl)amine, N-methyldiisopropylamine, N-methyldi(n-butyl)amine, N-methyldiisobutylamine, triethylamine, N,N-diethyl-n-butylamine, N,N-diisopropylethylamine, N,N-di(n-butyl)ethylamine, tri(n-propyl)amine, tri(i-propyl)amine, tri(n-butyl)amine, tri(i-butyl)amine, 1-methylacetylidine, 1-methylpyrrolidine, 1-methylpiperidine; triarylamine compounds such as triphenylamine; alkyldiarylamine compounds such as N-methyldiphenylamine, N-ethyldiphenylamine, 9-methylcarbazole, 9-ethylcarbazole;Examples of tertiary amine compounds include dialkylarylamine compounds such as N,N-diethylaniline, N,N-di(n-propyl)aniline, N,N-di(i-propyl)aniline, and N,N-di(n-butyl)aniline. However, considering the balance between the solubility of the amine adduct and the charge transport properties of the resulting organic functional membrane, tertiary amine compounds are preferred, trialkylamine compounds are more preferred, and triethylamine is even more preferred. Amine adducts can be obtained by adding a polythiophene derivative to the amine itself or a solution thereof and stirring thoroughly.

[0068] Furthermore, the above-mentioned polythiophene derivative or its amine adduct may be used after being treated with a reducing agent. In polythiophene derivatives or their amine adducts, the chemical structure of some of the repeating units that constitute them may be an oxidized structure called a "quinoid structure." The term "quinoid structure" is used in contrast to the term "benzenoid structure." While the latter is a structure containing an aromatic ring, the former refers to a structure in which the double bond within the aromatic ring moves out of the ring (resulting in the disappearance of the aromatic ring), and two extra-ring double bonds are formed that are conjugated to the other double bonds remaining in the ring. For those skilled in the art, the relationship between these two structures can be easily understood from the structural relationship between benzoquinone and hydroquinone. The quinoid structures of repeating units of various conjugated polymers are well known to those skilled in the art. As an example, the quinoid structure corresponding to the repeating unit of a polythiophene derivative containing the repeating unit represented by the above formula (H1) is shown in the following formula (H1').

[0069] [ka] (In the formula, R 1 and R 2 This is as defined in equation (H1) above.

[0070] This quinoid structure is generated by a process in which a polythiophene derivative containing the repeating unit represented by the above formula (H1) undergoes an oxidation reaction with a dopant, a so-called doping reaction, and forms part of the structures called "polaron structures" and "bipolaron structures" that impart charge transport properties to the polythiophene derivative. These structures are publicly known. In the fabrication of organic EL devices, the introduction of "polaron structures" and / or "bipolaron structures" is essential, and in fact, when fabricating organic EL devices, this is achieved by intentionally inducing the above doping reaction when firing a thin film formed from a charge transport varnish. The presence of a quinoid structure in the polythiophene derivative before this doping reaction is thought to be because the polythiophene derivative underwent an unintended oxidation reaction equivalent to a doping reaction during its manufacturing process (particularly the sulfonation step).

[0071] There is a correlation between the amount of quinoid structure contained in the above-mentioned polythiophene derivatives and their solubility and dispersibility in organic solvents. As the amount of quinoid structure increases, the solubility and dispersibility tend to decrease. Therefore, introducing quinoid structures after a thin film has been formed from a charge-transporting varnish does not cause problems. However, if an excessive amount of quinoid structure is introduced into the polythiophene derivative due to the above-mentioned unintended oxidation reaction, it may interfere with the production of the charge-transporting varnish. It is known that there is variability in the solubility and dispersibility of polythiophene derivatives in organic solvents. One of the reasons for this is thought to be that the amount of quinoid structure introduced into the polythiophene due to the above-mentioned unintended oxidation reaction varies depending on the differences in the production conditions of each polythiophene derivative. Therefore, when the above-mentioned polythiophene derivative is subjected to a reduction treatment using a reducing agent, even if an excess of quinoid structures is introduced into the polythiophene derivative, the reduction reduces the quinoid structures, improving the solubility and dispersibility of the polythiophene derivative in organic solvents. This makes it possible to stably produce a good charge-transporting varnish that gives a thin film with excellent homogeneity.

[0072] The conditions for the reduction treatment are not particularly limited as long as they allow for the reduction of the quinoid structure to a non-oxidized structure, i.e., to the benzenoid structure (for example, in the case of a polythiophene derivative containing a repeating unit represented by formula (H1), the quinoid structure represented by formula (H1') is converted to the structure represented by formula (H1)). For example, this treatment can be carried out simply by contacting the polythiophene derivative or amine adduct with a reducing agent, either in the presence or absence of a suitable solvent. There are no particular restrictions on such reducing agents as long as the reduction is carried out properly, but commercially available and readily available options such as aqueous ammonia and hydrazine are suitable. Furthermore, the amount of reducing agent cannot be specified in general, as it varies depending on the amount of reducing agent used. However, for 100 parts by mass of polythiophene derivative or amine adduct to be treated, it is usually 0.1 parts by mass or more, from the viewpoint of ensuring proper reduction, and 10 parts by mass or less, from the viewpoint of preventing excess reducing agent from remaining.

[0073] One specific method of reduction treatment involves stirring the polythiophene derivative or amine adduct overnight in 28% ammonia water at room temperature. This relatively mild reduction treatment significantly improves the solubility and dispersibility of the polythiophene derivative or amine adduct in organic solvents.

[0074] In the charge-transporting varnish of the present invention, when an amine adduct of a polythiophene derivative is used, the reduction treatment may be performed either before or after the formation of the amine adduct.

[0075] Furthermore, this reduction treatment alters the solubility and dispersibility of the polythiophene derivative or its amine adduct in the solvent. As a result, the polythiophene derivative or its amine adduct, which was not dissolved in the reaction system at the start of the treatment, may be dissolved by the completion of the treatment. In such cases, an organic solvent incompatible with the polythiophene derivative or its amine adduct (such as acetone or isopropyl alcohol in the case of sulfonated polythiophene) can be added to the reaction system to cause a precipitate of the polythiophene derivative or its amine adduct, which can then be recovered by filtration or other methods.

[0076] The weight-average molecular weight of a polythiophene derivative or its amine adduct containing a repeating unit represented by formula (H1) is preferably about 1,000 to 1,000,000, more preferably about 5,000 to 100,000, and even more preferably about 10,000 to about 50,000. Setting the weight-average molecular weight above the lower limit ensures good conductivity with good reproducibility, while setting it below the upper limit improves solubility in solvents. This weight-average molecular weight is the polystyrene equivalent value calculated by GPC.

[0077] The polythiophene derivative or its amine adduct contained in the charge-transporting varnish used in the present invention may be just one polythiophene derivative or its amine adduct containing a repeating unit represented by formula (H1), or it may be two or more. Furthermore, the polythiophene derivative containing the repeating unit represented by formula (H1) may be a commercially available product or one polymerized by a known method using thiophene derivatives as starting materials. In either case, it is preferable to use a purified product obtained by methods such as reprecipitation or ion exchange. By using a purified product, the properties of the organic EL device equipped with a thin film obtained from the charge-transporting varnish of the present invention can be further enhanced.

[0078] Furthermore, the sulfonation of conjugated polymers and sulfonated conjugated polymers (including sulfonated polythiophenes) are described in U.S. Patent No. 8,017,241 by Seshadri et al. Sulfonated polythiophenes are described in International Publication No. 2008 / 073149 and International Publication No. 2016 / 171935.

[0079] Furthermore, at least a portion of the polythiophene derivative or its amine adduct containing the repeating unit represented by the above formula (H1) is dissolved in the solvent described later.

[0080] In the present invention, when using a polythiophene derivative or its amine adduct containing a repeating unit represented by formula (H1), a charge transport substance consisting of the polythiophene derivative or its amine adduct and other charge transport compounds may be used in combination. However, it is preferable that only the polythiophene derivative or its amine adduct containing a repeating unit represented by formula (H1) is included.

[0081] When using a polythiophene derivative or its amine adduct containing repeating units represented by formula (H1), the content of the charge-transporting substance in the charge-transporting varnish is usually appropriately determined in the range of 0.05 to 40% by mass, preferably 0.1 to 35% by mass, of the solid content, taking into consideration the desired film thickness, varnish viscosity, etc.

[0082] Another preferred embodiment of the charge-transporting material is one represented by the following formulas (H2) and (H3).

[0083] [ka]

[0084] Furthermore, the aniline derivative represented by formula (H2) may also be an oxidized aniline derivative (quinone diimine derivative) having a quinone diimine structure shown in the following formula within its molecule. Methods for oxidizing an aniline derivative to a quinone diimine derivative include those described in International Publication No. 2008 / 010474 and International Publication No. 2014 / 119782.

[0085] [ka]

[0086] In formula (H2), R 1 ~R 6 These are, independently, a hydrogen atom, a halogen atom, a nitro group, a cyano group, an amino group, and Z. 1 A C1-C20 alkyl group, a C2-C20 alkenyl group, or a C2-C20 alkynyl group, which may be substituted with Z 2 An aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, which may be substituted with -NHY 1 , -NY 2 Y 3 ,-OY 4 , or -SY 5 Represents the base, Y 1 ~Y 5 Each of them is independent of Z 1 A C1-C20 alkyl group, a C2-C20 alkenyl group, or a C2-C20 alkynyl group, or Z may be substituted. 2 This represents an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, which may be substituted with Z. 1 is a halogen atom, nitro group, cyano group, amino group, or Z 3 This represents an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, which may be substituted with Z. 2 is a halogen atom, nitro group, cyano group, amino group, or Z 3 It represents an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an alkynyl group having 2 to 20 carbon atoms, which may be substituted with Z. 3k represents a halogen atom, nitro group, cyano group, or amino group, and k and l are each independent integers from 1 to 5.

[0087] In formula (H3), R 7 ~R 10 These are, independently, a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a thiol group, a phosphoric acid group, a sulfo group, a carboxyl group, and Z. 1 A carbon 1-20 alkoxy group, a carbon 1-20 thioalkoxy group, a carbon 1-20 alkyl group, a carbon 2-20 alkenyl group or a carbon 2-20 alkynyl group, Z 2 R represents an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or an acyl group having 1 to 20 carbon atoms, which may be substituted with R. 11 ~R 14 Each of these independently represents a hydrogen atom, a phenyl group, a naphthyl group, a pyridyl group, a pyrimidinyl group, a pyridadinyl group, a pyrazinyl group, a furanyl group, a pyrrolyl group, a pyrazolyl group, an imidazolyl group, a thienyl group (these groups may be substituted with a halogen atom, a nitro group, a cyano group, a hydroxyl group, a thiol group, a phosphoric acid group, a sulfo group, a carboxyl group, a carbon 1-20 alkoxy group, a carbon 1-20 thioalkoxy group, a carbon 1-20 alkyl group, a carbon 1-20 haloalkyl group, a carbon 2-20 alkenyl group, a carbon 2-20 alkynyl group, a carbon 6-20 aryl group, a carbon 7-20 aralkyl group, or a carbon 1-20 acyl group), or a group represented by formula (H3a) (where R 11 ~R 14 At least one of them is a hydrogen atom. ), m represents an integer between 2 and 5. 1 and Z 2 This expresses the same meaning as above.

[0088] [ka]

[0089] In formula (H3a), R 15 ~R 18These are, independently, a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a thiol group, a phosphoric acid group, a sulfo group, a carboxyl group, and Z. 1 A carbon 1-20 alkoxy group, a carbon 1-20 thioalkoxy group, a carbon 1-20 alkyl group, a carbon 2-20 alkenyl group or a carbon 2-20 alkynyl group, Z 2 R represents an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or an acyl group having 1 to 20 carbon atoms, which may be substituted with R. 19 and R 20 Each of these independently represents a phenyl group, naphthyl group, anthryl group, pyridyl group, pyrimidinyl group, pyridadinyl group, pyrazinyl group, furanyl group, pyrrolyl group, pyrazolyl group, imidazolyl group, or thienyl group (these groups may be bonded to each other to form rings, or they may be substituted with halogen atoms, nitro groups, cyano groups, hydroxyl groups, thiol groups, phosphoric acid groups, sulfo groups, carboxyl groups, alkoxy groups with 1 to 20 carbon atoms, thioalkoxy groups with 1 to 20 carbon atoms, alkyl groups with 1 to 20 carbon atoms, haloalkyl groups with 1 to 20 carbon atoms, alkenyl groups with 2 to 20 carbon atoms, alkynyl groups with 2 to 20 carbon atoms, aryl groups with 6 to 20 carbon atoms, aralkyl groups with 7 to 20 carbon atoms, or acyl groups with 1 to 20 carbon atoms). 1 and Z 2 This expresses the same meaning as above.

[0090] In the above formulas, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, and the like. C1-C20 alkyl groups can be linear, branched, or cyclic. Examples include linear or branched alkyl groups with 1-20 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl groups; and cyclic alkyl groups with 3-20 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, and bicyclodecyl groups.

[0091] Specific examples of alkenyl groups having 2 to 20 carbon atoms include ethenyl, n-1-propenyl, n-2-propenyl, 1-methylethenyl, n-1-butenyl, n-2-butenyl, n-3-butenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, 1-ethylethenyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, n-1-pentenyl, n-1-decenyl, and n-1-eicocenyl groups.

[0092] Specific examples of alkynyl groups having 2 to 20 carbon atoms include ethynyl, n-1-propynyl, n-2-propynyl, n-1-butynyl, n-2-butynyl, n-3-butynyl, 1-methyl-2-propynyl, n-1-pentynyl, n-2-pentynyl, n-3-pentynyl, n-4-pentynyl, 1-methyl-n-butynyl, 2-methyl-n-butynyl, 3-methyl-n-butynyl, 1,1-dimethyl-n-propynyl, n-1-hexynyl, n-1-decinyl, n-1-pentadecinyl, and n-1-eicosinyl groups.

[0093] Specific examples of aryl groups having 6 to 20 carbon atoms include phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, and 9-phenanthryl groups.

[0094] Specific examples of aralkyl groups having 7 to 20 carbon atoms include benzyl, phenylethyl, phenylpropyl, naphthylmethyl, naphthylethyl, and naphthylpropyl groups.

[0095] Specific examples of heteroaryl groups having 2 to 20 carbon atoms include 2-thienyl, 3-thienyl, 2-furanyl, 3-furanyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 3-isoxazolyl, 4-isoxazolyl, 5-isoxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, 2-imidazolyl, 4-imidazolyl, 2-pyridyl, 3-pyridyl, and 4-pyridyl groups.

[0096] Examples of C1-C20 haloalkyl groups include those in which at least one hydrogen atom of the above C1-C20 alkyl group is substituted with a halogen atom, but among these, fluoroalkyl groups are preferred, and perfluoroalkyl groups are more preferred. Specific examples include fluoromethyl, difluoromethyl, trifluoromethyl, pentafluoroethyl, 2,2,2-trifluoroethyl, heptafluoropropyl, 2,2,3,3,3-pentafluoropropyl, 2,2,3,3-tetrafluoropropyl, 2,2,2-trifluoro-1-(trifluoromethyl)ethyl, nonafluorobutyl, 4,4,4-trifluorobutyl, undecafluoropentyl, 2,2,3,3,4,4,5,5,5-nonafluoropentyl, 2,2,3,3,4,4,5,5-octafluoropentyl, tridecafluorohexyl, 2,2,3,3,4,4,5,5,6,6,6-undecafluorohexyl, 2,2,3,3,4,4,5,5,6,6-decafluorohexyl, and 3,3,4,4,5,5,6,6,6-nonafluorohexyl groups.

[0097] Specific examples of alkoxy groups having 1 to 20 carbon atoms include methoxy, ethoxy, n-propoxy, i-propoxy, c-propoxy, n-butoxy, i-butoxy, s-butoxy, t-butoxy, n-pentoxy, n-hexoxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy, n-undecyloxy, n-dodecyloxy, n-tridecyloxy, n-tetradecyloxy, n-pentadecyloxy, n-hexadecyloxy, n-heptadecyloxy, n-octadecyloxy, n-nonadecyloxy, and n-eicosanyloxy groups.

[0098] Specific examples of thioalkoxy (alkylthio) groups having 1 to 20 carbon atoms include methylthio, ethylthio, n-propylthio, isopropylthio, n-butylthio, isobutylthio, s-butylthio, t-butylthio, n-pentylthio, n-hexylthio, n-heptylthio, n-octylthio, n-nonylthio, n-decylthio, n-undecylthio, n-dodecylthio, n-tridecylthio, n-tetradecylthio, n-pentadecylthio, n-hexadecylthio, n-heptadecylthio, n-octadecylthio, n-nonadecylthio, and n-eicosanylthio groups.

[0099] Specific examples of acyl groups with 1 to 20 carbon atoms include formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, isovaleryl, and benzoyl groups.

[0100] In equation (H2), R 1 ~R 6 is a hydrogen atom, a halogen atom, Z 1 A C1-C20 alkyl group that may be substituted with Z 2 A C6-C20 aryl group may be substituted with -NHY 1 , -NY 2 Y 3 ,-OY 4 , or -SY 5 Preferably, in this case, Y 1 ~Y 5 is, Z 1A C1-C10 alkyl group or Z which may be substituted. 2 A C6-C10 aryl group which may be substituted with Z is preferred, 1 A C1-C6 alkyl group or Z which may be substituted. 2 A phenyl group that may be substituted is more preferred, and an alkyl group or phenyl group having 1 to 6 carbon atoms is even more preferred. In particular, R 1 ~R 6 is a hydrogen atom, a fluorine atom, a methyl group, a phenyl group or a diphenylamino group (Y 2 and Y 3 -NY is a phenyl group 2 Y 3 ) is more preferable, R 1 ~R 4 is a hydrogen atom, and R 5 and R 6 However, a hydrogen atom or a diphenylamino group is even more preferable.

[0101] In particular, R 1 ~R 6 and Y 1 ~Y 5 In Z 1 is a halogen atom or Z 3 A C6-C10 aryl group which may be substituted is preferred, a fluorine atom or a phenyl group is more preferred, and the absence of such a group (i.e., an unsubstituted group) is even more preferred, and Z 2 is a halogen atom or Z 3 A C1-C10 alkyl group which may be substituted is preferred, a fluorine atom or a C1-C6 alkyl group is more preferred, and its absence (i.e., an unsubstituted group) is even more preferred. Also, Z 3 A halogen atom is preferred, a fluorine atom is more preferred, and its absence (i.e., it is an unsubstituted group) is even more preferred. From the viewpoint of increasing the solubility of the aniline derivative represented by formula (H2), k and l are preferably k+l≦8, and more preferably k+l≦5.

[0102] In equation (H3), R 7 ~R 10 The elements are preferably hydrogen atoms, halogen atoms, C1-C4 alkyl groups, C1-C4 perfluoroalkyl groups, and C1-C4 alkoxy groups, with hydrogen atoms being more preferred. Furthermore, considering the need to increase the solubility of the aniline derivative represented by formula (H3) in the solvent and to improve the uniformity of the resulting thin film, R 11 and R 13 It is preferable that both are hydrogen atoms. In particular, R 11 and R 13 Both are hydrogen atoms, R 12 and R 14 However, each is preferably independently a phenyl group (this phenyl group may be substituted with a halogen atom, a nitro group, a cyano group, a hydroxyl group, a thiol group, a phosphoric acid group, a sulfo group, a carboxyl group, a carbon 1-20 alkoxy group, a carbon 1-20 thioalkoxy group, a carbon 1-20 alkyl group, a carbon 1-20 haloalkyl group, a carbon 2-20 alkenyl group, a carbon 2-20 alkynyl group, a carbon 6-20 aryl group, a carbon 7-20 aralkyl group, or a carbon 1-20 acyl group), and R 11 and R 13 However, both are hydrogen atoms, R 12 and R 14 However, each independently, a phenyl group, or R 19’ and R 20’ It is more preferable that both are phenyl groups and are represented by the following formula (H3a′), R 11 and R 13 However, both are hydrogen atoms, R 12 and R 14 However, it is even more preferable that both are phenyl groups. Furthermore, considering factors such as the availability of the compound, ease of manufacture, and cost, m is preferably 2 to 4. Considering the need to improve solubility in the solvent, 2 or 3 is more preferable. Considering the balance between the availability of the compound, ease of manufacture, manufacturing cost, solubility in the solvent, and the transparency of the resulting thin film, 2 is optimal.

[0103] [ka]

[0104] The aniline derivatives represented by formulas (H2) and (H3) may be commercially available or prepared by known methods such as those described in the above publications. In either case, it is preferable to use a purified aniline derivative, such as by recrystallization or vapor deposition, before preparing the charge-transporting varnish. Using a purified derivative can further enhance the properties of electronic devices equipped with a thin film obtained from the varnish. When purifying by recrystallization, solvents such as 1,4-dioxane and tetrahydrofuran can be used.

[0105] In the present invention, the charge transporting material represented by formulas (H2) and (H3) may be a single compound selected from the compounds represented by formulas (H2) and (H3) (i.e., a molecular weight distribution dispersion of 1), or two or more compounds may be used in combination.

[0106] Specific examples of charge-transporting materials represented by formulas (H2) and (H3) that can be suitably used in the present invention are listed below, but are not limited to these.

[0107] [ka]

[0108] [ka] (In the formula, DPA represents a diphenylamino group.)

[0109] In the charge-transporting varnish of the present invention, the amount of fluorinated aryl sulfonic acid polymer compound used as a dopant substance is preferably about 0.01 to 20.0, more preferably about 0.05 to 15, in terms of molar ratio, per 1 charge-transporting substance such as a polythiophene derivative or an arylamine derivative. In addition to the fluorinated aryl sulfonic acid polymer compound, the charge-transporting varnish of the present invention may contain known organic dopant substances or inorganic dopant substances, but it is preferable that it does not contain these other dopant substances.

[0110] When preparing the charge-transporting varnish of the present invention, a highly polar solvent capable of well dissolving the charge-transporting substance, dopant substance, etc., can be used as the solvent. Alternatively, a low-polarity solvent may be used if necessary, as it offers superior process compatibility compared to a highly polar solvent. In this invention, a low-polarity solvent is defined as one with a relative permittivity of less than 7 at a frequency of 100 kHz, and a highly polar solvent is defined as one with a relative permittivity of 7 or more at a frequency of 100 kHz.

[0111] Examples of low-polarity solvents include, Chlorinated solvents such as chloroform and chlorobenzene; Aromatic hydrocarbon solvents such as toluene, xylene, tetralin, cyclohexylbenzene, and decylbenzene; Aliphatic alcohol solvents such as 1-octanol, 1-nonanol, and 1-decanol; Ether-based solvents such as tetrahydrofuran, dioxane, anisole, 4-methoxytoluene, 3-phenoxytoluene, dibenzyl ether, diethylene glycol dimethyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, and triethylene glycol butyl methyl ether; Ester solvents such as methyl benzoate, ethyl benzoate, butyl benzoate, isoamyl benzoate, bis(2-ethylhexyl) phthalate, dibutyl maleate, dibutyl oxalate, hexyl acetate, diethylene glycol monoethyl ether acetate, and diethylene glycol monobutyl ether acetate. These are some examples.

[0112] Furthermore, examples of highly polar solvents include, Amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylisobutylamide, N-methylpyrrolidone, and 1,3-dimethyl-2-imidazolidinone; Ketone solvents such as ethyl methyl ketone, isophorone, and cyclohexanone; Cyano solvents such as acetonitrile and 3-methoxypropionitrile; Polyhydric alcohol solvents such as ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, 1,3-butanediol, and 2,3-butanediol; Monohydric alcohol solvents other than aliphatic alcohols such as diethylene glycol monomethyl ether, diethylene glycol monophenyl ether, triethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, benzyl alcohol, 2-phenoxyethanol, 2-benzyloxyethanol, 3-phenoxybenzyl alcohol, and tetrahydrofurfuryl alcohol; Sulfoxide solvents such as dimethyl sulfoxide These are some examples.

[0113] Furthermore, the charge-transporting varnish of the present invention may contain one or more metal oxide nanoparticles. Nanoparticles refer to fine particles whose average particle diameter for primary particles is on the order of nanometers (typically 500 nm or less). Metal oxide nanoparticles refer to metal oxides formed into nanoparticles. The primary particle size of the metal oxide nanoparticles is not particularly limited as long as it is nano-sized, but is preferably 2 to 150 nm, more preferably 3 to 100 nm, and even more preferably 5 to 50 nm. The particle size was measured using nitrogen adsorption isotherms by the BET method.

[0114] The metals constituting the above metal oxide nanoparticles include not only metals in the usual sense, but also metalloids. While there are no particular limitations on the metals used in the ordinary sense, it is preferable to use one or more selected from the group consisting of tin (Sn), titanium (Ti), aluminum (Al), zirconium (Zr), zinc (Zn), niobium (Nb), tantalum (Ta), and W (tungsten). On the other hand, metalloids refer to elements whose chemical and / or physical properties are intermediate between those of metals and nonmetals. While there is no universally established definition of metalloids, in this invention, six elements—boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), and tellurium (Te)—are considered metalloids. These metalloids may be used individually, in combination of two or more, or in combination with metals in the usual sense.

[0115] In particular, the metal oxide nanoparticles preferably contain oxides of one or more metals selected from boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), tin (Sn), titanium (Ti), aluminum (Al), zirconium (Zr), zinc (Zn), niobium (Nb), tantalum (Ta), and w (tungsten). When the metals are a combination of two or more, the metal oxide may be a mixture of oxides of individual metals or a composite oxide containing multiple metals.

[0116] Specific examples of metal oxides include B2O3, B2O, SiO2, SiO, GeO2, GeO, As2O4, As2O3, As2O5, Sb2O3, Sb2O5, TeO2, SnO2, ZrO2, Al2O3, ZnO, etc., but B2O3, B2O, SiO2, SiO, GeO2, GeO, As2O4, As2O3, As2O5, SnO2, SnO, Sb2O3, TeO2, and mixtures thereof are preferred, with SiO2 being more preferred.

[0117] The amount of metal oxide nanoparticles is not particularly limited, but from the viewpoint of improving the transparency of the resulting thin film and enhancing the uniformity of the film, the lower limit of the amount in the solid content is usually 50% by mass, preferably 60% by mass, more preferably 65% ​​by mass, and the upper limit is usually 95% by mass, preferably 90% by mass.

[0118] In particular, in the present invention, it is preferable to use silica sol in which SiO2 nanoparticles are dispersed in a dispersion medium as the metal oxide nanoparticles. The silica sol is not particularly limited and can be appropriately selected from known silica sols. Commercially available silica sols are usually in the form of dispersions. Examples of commercially available silica sols include those in which SiO2 nanoparticles are dispersed in various solvents, such as water, methanol, methyl ethyl ketone, methyl isobutyl ketone, N,N-dimethylacetamide, ethylene glycol, isopropanol, methanol, ethylene glycol monopropyl ether, cyclohexanone, ethyl acetate, toluene, and propylene glycol monomethyl ether acetate.

[0119] Specific examples of commercially available silica sols include, but are not limited to, water-dispersible silica sols such as Snowtex® ST-O, ST-OS, ST-O-40, ST-OL manufactured by Nissan Chemical Corporation, and Silica Doll 20, 30, 40 manufactured by Nippon Chemical Industrial Co., Ltd.; and organosilica sols such as methanol silica sol, MA-ST-M, MA-ST-L, IPA-ST, IPA-ST-L, IPA-ST-ZL, EG-ST manufactured by Nissan Chemical Corporation. Furthermore, while the solid content concentration of the silica sol is not particularly limited, it is preferably 5 to 60% by mass, more preferably 10 to 50% by mass, and even more preferably 15 to 30% by mass.

[0120] The amount of silica sol used is determined appropriately, taking into account its concentration, so that the final amount of silica contained in the charge-transporting varnish is equal to the amount of metal oxide nanoparticles mentioned above.

[0121] Furthermore, when the resulting thin film of the charge-transporting varnish of the present invention is used as a hole injection layer for an organic EL device, it may contain an organic silane compound for the purpose of improving the injection properties into the hole transport layer and improving the device's lifetime characteristics. The amount of organic silane compound is usually about 1 to 30% by mass relative to the total mass of the charge-transporting substance and the dopant substance. Examples of organosilane compounds include dialkoxysilane compounds, trialkoxysilane compounds, or tetraalkoxysilane compounds.

[0122] The viscosity of the charge-transporting varnish is determined appropriately depending on the thickness of the thin film to be prepared and the solid content concentration, but is usually 1 to 50 mPa·s at 25°C. In this invention, "solid content" refers to components other than the solvent contained in the charge-transporting varnish. Furthermore, the solid content concentration of the charge-transporting varnish is appropriately determined considering factors such as the viscosity and surface tension of the varnish and the thickness of the thin film to be produced, but is usually around 0.1 to 10.0 mass%, and more preferably around 0.5 to 5.0 mass, and more preferably around 1.0 to 3.0 mass, in order to improve the applicability of the varnish.

[0123] There are no particular limitations on the method for preparing charge-transporting varnishes, but examples include a method in which a charge-transporting substance and a dopant substance are dissolved in a highly polar solvent, and then a low-polarity solvent and surface-treated metal oxide nanoparticles are added thereto, or a method in which a highly polar solvent and a low-polarity solvent are mixed, the charge-transporting substance and the dopant substance are dissolved therein, and then surface-treated metal oxide nanoparticles are added.

[0124] In particular, when preparing charge-transporting varnishes, it is desirable to use a solution obtained by dissolving charge-transporting substances, dopant substances, etc., in an organic solvent and then filtering it using a sub-micrometer-order filter, in order to reproducibly obtain thin films with higher flatness.

[0125] The charge-transporting varnish described above can be easily used to manufacture charge-transporting thin films, and therefore can be suitably used in the manufacture of electronic devices, particularly organic EL devices. In this case, the charge-transporting thin film can be formed by applying the aforementioned charge-transporting varnish to a substrate and firing it. The method of applying the varnish is not particularly limited and includes methods such as dipping, spin coating, transfer printing, roll coating, brush coating, inkjet coating, spray coating, and slit coating. It is preferable to adjust the viscosity and surface tension of the varnish according to the application method.

[0126] Furthermore, the firing atmosphere for the charge-transporting varnish after coating is not particularly limited. A thin film with a uniform film surface and high charge transport properties can be obtained not only in an atmospheric atmosphere but also in an inert gas such as nitrogen or in a vacuum. However, depending on the type of dopant material used, a thin film with charge transport properties can sometimes be reproducibly obtained by firing the varnish in an atmospheric atmosphere.

[0127] The firing temperature is appropriately determined within a range of approximately 100 to 260°C, taking into consideration the intended use of the resulting thin film, the degree of charge transport properties to be imparted to the thin film, the type of solvent and its boiling point, etc. For example, when the resulting thin film is used as a hole injection layer in an organic EL device, a temperature of approximately 140 to 250°C is preferred, and approximately 145 to 240°C is more preferred. However, when the above-mentioned arylamine compound is used as the charge transport material, a thin film with good charge transport properties can be obtained even with low-temperature firing of 200°C or below. Furthermore, during firing, two or more temperature changes may be applied to achieve higher uniformity in film formation or to promote the reaction on the substrate. Heating can be carried out using appropriate equipment such as a hot plate or oven.

[0128] The thickness of the charge-transporting thin film is not particularly limited, but when used as a functional layer between the anode and the light-emitting layer, such as a hole injection layer or hole transport layer in an organic EL device, a thickness of 5 to 300 nm is preferred. Methods for changing the film thickness include changing the solid content concentration in the varnish or changing the amount of solution on the substrate during coating.

[0129] [3] Organic EL elements When the above-mentioned charge-transporting thin film is applied to an organic EL element, the organic EL element can be configured to have the charge-transporting thin film between a pair of electrodes constituting the element. Typical configurations of organic EL devices include (a) to (f) below, but are not limited to these. In the configurations below, an electron blocking layer may be provided between the light-emitting layer and the anode, and a hole blocking layer may be provided between the light-emitting layer and the cathode, if necessary. Furthermore, a hole injection layer, a hole transport layer, or a hole injection transport layer may also function as an electron blocking layer, and an electron injection layer, an electron transport layer, or an electron injection transport layer may also function as a hole blocking layer. In addition, any functional layer may be provided between each layer as necessary. (a) Anode / Hole injection layer / Hole transport layer / Emitting layer / Electron transport layer / Electron injection layer / Cathode (b) Anode / Hole injection layer / Hole transport layer / Emitting layer / Electron injection transport layer / Cathode (c) Anode / Hole injection transport layer / Emitting layer / Electron transport layer / Electron injection layer / Cathode (d) Anode / Hole injection transport layer / Emitting layer / Electron injection transport layer / Cathode (e) Anode / Hole injection layer / Hole transport layer / Emitting layer / Cathode (f) Anode / Hole injection transport layer / Emitting layer / Cathode

[0130] The terms "hole injection layer," "hole transport layer," and "hole injection transport layer" refer to layers formed between the light-emitting layer and the anode, which have the function of transporting holes from the anode to the light-emitting layer. When only one layer of hole-transporting material is provided between the light-emitting layer and the anode, that layer is the "hole injection transport layer." When two or more layers of hole-transporting material are provided between the light-emitting layer and the anode, the layer closest to the anode is the "hole injection layer," and the other layers are the "hole transport layers." In particular, the hole injection (transport) layer is made of a thin film that is excellent not only in its ability to accept holes from the anode but also in its ability to inject holes into the hole transport (light-emitting) layer. "Electron injection layer," "electron transport layer," and "electron injection transport layer" refer to layers formed between the light-emitting layer and the cathode that have the function of transporting electrons from the cathode to the light-emitting layer. When only one layer of electron-transporting material is provided between the light-emitting layer and the cathode, that is the "electron injection transport layer." When two or more layers of electron-transporting material are provided between the light-emitting layer and the cathode, the layer closest to the cathode is the "electron injection layer," and the other layers are the "electron transport layers." A "luminescent layer" is an organic layer that has a luminescent function, and when a doping system is employed, it contains a host material and a dopant material. In this case, the host material mainly has the function of promoting the recombination of electrons and holes and confining excitons within the luminescent layer, while the dopant material has the function of efficiently emitting light from the excitons obtained by the recombination. In the case of a phosphorescent device, the host material mainly has the function of confining the excitons generated by the dopant within the luminescent layer.

[0131] The charge-transporting thin film of the present invention can be used as a functional layer provided between the anode and the light-emitting layer in an organic EL device, and is particularly suitable as a hole injection layer, a hole transport layer, or a hole injection transport layer, more suitable as a hole injection layer or a hole transport layer, and even more suitable as a hole injection layer.

[0132] The following are examples of materials and manufacturing methods used when fabricating an EL element using the charge-transporting varnish of the present invention, but are not limited to these. An example of a method for fabricating an OLED element having a hole injection layer made of a thin film obtained from the charge-transporting varnish of the present invention is as follows. It is preferable to pre-treat the electrodes by cleaning with alcohol, pure water, etc., or by surface treatment such as UV ozone treatment or oxygen-plasma treatment, to the extent that it does not adversely affect the electrodes. A hole injection layer made of the charge-transporting thin film of the present invention is formed on the anode substrate by the method described above. This is then introduced into a vacuum deposition apparatus, and the hole transport layer, light-emitting layer, electron transport layer, electron transport layer / hole-blocking layer, electron injection layer, and cathode metal are deposited sequentially. Alternatively, instead of forming the hole transport layer and light-emitting layer by deposition in the above method, these layers are formed by a wet process using a hole transport layer-forming composition containing a hole-transporting polymer and a light-emitting layer-forming composition containing a light-emitting polymer. If necessary, an electron-blocking layer may be provided between the light-emitting layer and the hole transport layer.

[0133] Examples of anode materials include transparent electrodes such as indium tin oxide (ITO) and indium zinc oxide (IZO), and metallic anodes composed of metals such as aluminum or alloys thereof, with planarized treatment being preferred. Polythiophene derivatives and polyaniline derivatives with high charge transport properties can also be used. Other metals that can make up a metallic anode include, but are not limited to, gold, silver, copper, indium, and alloys thereof.

[0134] Examples of materials that form the hole transport layer include triarylamines such as (triphenylamine) dimer derivatives, [(triphenylamine) dimer] spirodimer, N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-benzidine (α-NPD), 4,4',4”-tris[3-methylphenyl(phenyl)amino]triphenylamine (m-MTDATA), and 4,4',4”-tris[1-naphthyl(phenyl)amino]triphenylamine (1-TNATA), as well as oligothiophenes such as 5,5”-bis-{4-[bis(4-methylphenyl)amino]phenyl}-2,2':5',2”-terthiophene (BMA-3T).

[0135] Examples of materials for forming the luminescent layer include, but are not limited to, low molecular weight luminescent materials such as metal complexes of 8-hydroxyquinoline such as aluminum complexes, metal complexes of 10-hydroxybenzo[h]quinoline, bisstyrylbenzene derivatives, bisstyrylarylene derivatives, metal complexes of (2-hydroxyphenyl)benzothiazole, and silole derivatives; and systems in which luminescent materials and electron transfer materials are mixed with high molecular weight compounds such as poly(p-phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly(3-alkylthiophene), and polyvinylcarbazole. Furthermore, when forming a light-emitting layer by vapor deposition, it may be co-deposited with a light-emitting dopant. Examples of light-emitting dopants include, but are not limited to, metal complexes such as tris(2-phenylpyridine)iridium(III) (Ir(ppy)3), naphthacene derivatives such as rubrene, quinacridone derivatives, and condensed polycyclic aromatic rings such as perylene.

[0136] Materials that form the electron transport layer / hole block layer include, but are not limited to, oxydiazole derivatives, triazole derivatives, phenanthroline derivatives, phenylquinoxaline derivatives, benzimidazole derivatives, and pyrimidine derivatives.

[0137] Materials used to form the electron injection layer include, but are not limited to, metal oxides such as lithium oxide (Li2O), magnesium oxide (MgO), and alumina (Al2O3), and metal fluorides such as lithium fluoride (LiF) and sodium fluoride (NaF). Examples of cathode materials include, but are not limited to, aluminum, magnesium-silver alloys, and aluminum-lithium alloys. Examples of materials that form the electron blocking layer include, but are not limited to, tris(phenylpyrazole)iridium.

[0138] Examples of hole-transporting polymers include poly[(9,9-dihexylfluorenyl-2,7-diyl)-co-(N,N'-bis{p-butylphenyl}-1,4-diaminophenylene)], 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)], and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)-benzidine]-end-capped with Examples include polysyl cisquinoxanes and poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(p-butylphenyl))diphenylamine)].

[0139] Examples of luminescent polymers include polyfluorene derivatives such as poly(9,9-dialkylfluorene) (PDAF), polyphenylene vinylene derivatives such as poly(2-methoxy-5-(2'-ethylhexoxy)-1,4-phenylene vinylene) (MEH-PPV), polythiophene derivatives such as poly(3-alkylthiophene) (PAT), and polyvinylcarbazole (PVCz).

[0140] As described above, the charge-transporting varnish of the present invention is suitably used for forming functional layers provided between the anode and the light-emitting layer, such as hole injection layers and hole transport layers in organic EL elements. However, it can also be used for forming charge-transporting thin films in other electronic elements such as organic photoelectric devices, organic thin-film solar cells, organic perovskite photoelectric devices, organic integrated circuits, organic field-effect transistors, organic thin-film transistors, organic light-emitting transistors, organic optical inspectors, organic photoreceptors, organic electric field quenching elements, light-emitting electrochemical batteries, quantum dot light-emitting diodes, quantum lasers, organic laser diodes, and organic plasma light-emitting elements. [Examples]

[0141] The present invention will be described in more detail below with reference to synthesis examples, preparation examples, examples, and comparative examples, but the present invention is not limited to the following examples. The apparatus used is as follows. (1) 1 H-NMR Bruker AVANCE III HD500MHz Nuclear Magnetic Resonance Spectrometer (2) Measurement of weight-average molecular weight (Mw) and number-average molecular weight (Mn) (Condition A) Shimadzu Corporation Prominence GPC instrument (Column: TSKgel α2500+α3000+α4000, Column temperature: 40℃, Detector: UV detector (254nm) and RI detector, Eluent: MeOH, LiBr (10mM), Column flow rate: 1mL / min), Standard sample: Polyethylene oxide (Condition B) Tosoh Corporation GPC instrument HLC-8320GPC (Column: Shodex KD-805, Column temperature: 50℃, Detector: UV detector (254nm) and RI detector, Eluent: DMF, LiBr (30mM), Phosphoric acid (30mM), THF (1%), Column flow rate: 1mL / min), Standard sample: Polyethylene oxide (3) Cleaning of the circuit board Circuit board cleaning equipment (reduced pressure plasma method) manufactured by Choshu Sangyo Co., Ltd. (4) Application of charge-transporting varnish Mikasa Corporation Spin Coater MS-A100 (5) Fabrication of organic EL elements Choshu Sangyo Co., Ltd. Multifunctional Vapor Deposition System C-E2L1G1-N (6) Measurement of brightness, etc. of organic EL elements EHC Corporation Multi-channel IVL measuring device (7) Measurement of the contact angle of charge-transporting thin films Kyowa Interface Science Co., Ltd. Contact angle meter DropMaster DM-700

[0142] [1] Synthesis of raw material compounds (monomers) [Synthesis Example 1] Synthesis of Compound 1 [ka]

[0143] In a three-necked flask, 10.0 g of sodium 1-naphthol-3,6-disulfonate (manufactured by Yamada Chemical Industries, Ltd.), 18.4 g of 2,3,4,5,6-pentafluorostyrene (manufactured by Tokyo Chemical Industries, Ltd., hereafter the same), and 5.02 g of sodium carbonate (manufactured by Kanto Chemical Co., Ltd.) were added. Then, 100 g of dimethyl sulfoxide (manufactured by Junsei Chemical Co., Ltd., hereafter the same) was added, and the mixture was stirred at 80°C for 30 hours under a nitrogen atmosphere. After cooling the reaction mixture to room temperature, 200 g of dimethyl sulfoxide was added, and the mixture was stirred at room temperature for 3 hours to dissolve the precipitated product. The resulting solution was filtered, and the filtrate was reduced in pressure to remove the solvent and obtain the crude product. The crude product was added to 900 g of a mixed solvent (1 / 1 (w / w)) of 2-propanol (manufactured by Junsei Chemical Co., Ltd.) and ethyl acetate (manufactured by Junsei Chemical Co., Ltd., hereafter the same), and the mixture was stirred at room temperature for 1 hour. The precipitated solid was collected by filtration, and the obtained solid was dried under reduced pressure to obtain compound 1 (yield 11.3 g, yield 76%). Compound 1 1 The H-NMR spectrum is shown below.

[0144] 1 H-NMR (500MHz, DMSO): δ5.87(d,J=11.5Hz,1H),6.12(d,J=18.0Hz,1H),6.72(dd,J=18.0,11.5Hz ,1H),6.99(s,1H),7.88(dd,J=8.5,1.5Hz,1H),7.97(s,1H),8.21(s,1H),8.25(d,J=8.5Hz,1H).

[0145] [2] Polymer synthesis [Example 1-1] Synthesis of Polymer A [ka]

[0146] Into a two-necked flask, 2.0 g of Compound 1 obtained in Synthesis Example 1 and 0.043 g of ammonium persulfate (manufactured by Tokyo Chemical Industry Co., Ltd.) were added. Further, 10 g of degassed ion-exchanged water was added thereto, and the mixture was stirred at 65 °C for 20 hours under a nitrogen atmosphere. After the reaction solution was cooled to room temperature, it was added dropwise to 150 g of methanol (manufactured by Junsei Chemical Co., Ltd., the same hereinafter), and the mixture was stirred at room temperature for 1 hour. The precipitated solid was collected by filtration, and the collected solid was dried under reduced pressure. After adding 5.5 g of ion-exchanged water to the obtained dried solid and dissolving it, 20 mL of a cation exchange resin (Dowex Monosphere 650C, manufactured by Fujifilm Wako Pure Chemical Corporation, the same hereinafter) was added, and the mixture was stirred at room temperature for 20 minutes and then filtered. The filtrate was concentrated under reduced pressure to remove the solvent, and Polymer A was obtained (0.95 g). Mw = 2340, Mn = 2270, Mw / Mn = 1.03 (GPC, Condition A)

[0147] [Example 1-2] Synthesis of Polymer B [Chemical formula]

[0148] Into a two-necked flask, 2.0 g of Compound 1 obtained in Synthesis Example 1, 0.74 g of 2,3,4,5,6-pentafluorostyrene, and 0.14 g of AIBN (manufactured by Fujifilm Wako Pure Chemical Corporation) were added. Further, 20 g of degassed dimethylformamide (manufactured by Junsei Chemical Co., Ltd.) was added thereto, and the mixture was stirred at 80 °C for 8 hours under a nitrogen atmosphere. After the reaction solution was cooled to room temperature, it was added to 200 g of a mixed solvent of methanol and ethyl acetate (1 / 3 (w / w)), and the mixture was stirred at room temperature for 1 hour. The precipitated solid was collected by filtration, and the collected solid was dried under reduced pressure. After adding 10 g of ion-exchanged water to the obtained dried solid and dissolving it, 20 mL of a cation exchange resin (Dowex Monosphere 650C) was added, and the mixture was stirred at room temperature for 20 minutes and then filtered. The filtrate was concentrated under reduced pressure to remove the solvent, and Polymer B was obtained (1.59 g). Mw = 5150, Mn = 3550, Mw / Mn = 1.23 (GPC, Condition B)

[0149] [3] Synthesis of Comparative Compounds [Comparative Example 1-1] Synthesis of Compound 2 [ka]

[0150] 1.3 g of compound 1 obtained in Synthesis Example 1 was dissolved in 56.5 g of deionized water, and ion exchange was performed by column chromatography using 150 mL of cation exchange resin (Dowex Monosphere 650C) with deionized water as the extraction solvent. The fraction around pH 1 was dried under reduced pressure to obtain compound 2 (10.24 g, yield 98.8%).

[0151] [4] Preparation of compositions for charge-transporting varnishes [Preparation Example 1-1] To 0.5 g of an amine adduct of a polythiophene derivative, which is a polymer containing repeating units represented by formula (H1a) and synthesized sequentially according to the methods described in U.S. Patent No. 8017241 and International Publication No. 2016 / 171935, 8.75 g of 1,3-dimethyl-2-imidazolidinone (manufactured by Kanto Chemical Co., Ltd., hereinafter the same) and 0.75 g of n-butylamine (manufactured by Tokyo Chemical Industry Co., Ltd.) were added, and the mixture was stirred at 80°C for 3 hours using a hot stirrer to obtain a solution in which polythiophene was dissolved.

[0152] [ka]

[0153] [Preparation Examples 1-2] 100 g of ST-OS (manufactured by Nissan Chemical Corporation), a water-dispersible silica sol, and dipropylene glycol monomethyl ether (manufactured by Kanto Chemical Co., Ltd., the same applies hereafter) were placed in a round-bottom flask. Using an evaporator, the water contained in ST-OS was replaced with dipropylene glycol monomethyl ether to obtain a silica sol dispersed in dipropylene glycol monomethyl ether (silica concentration 9.43%).

[0154] [Preparation Examples 1-3] A solution of diethylene glycol (manufactured by Kanto Chemical Co., Ltd., hereafter the same) containing 5.0% by mass of polymer A obtained in Example 1-1 was prepared. The above solution was prepared by stirring at 50°C for 1 hour using a hot stirrer.

[0155] [Preparation Examples 1-4] A 1,3-dimethyl-2-imidazolidinone solution containing 10% by mass of polymer B obtained in Examples 1-2 was prepared. The solution was prepared by stirring at 50°C for 1 hour using a hot stirrer.

[0156] [Preparation Examples 1-5] A commercially available aqueous solution of D-66-20BS (AQUIVION, Solvay), a copolymer of tetrafluoroethylene and sulfonated vinyl ether, was prepared by removing the water using an evaporator, and then drying it in a vacuum dryer at 80°C for 1 hour to obtain D-66-20BS powder. Subsequently, a 1,3-dimethyl-2-imidazolidinone solution containing 5% by mass of D-66-20BS was prepared. This solution was prepared by stirring with a hot stirrer at 80°C for 2 hours.

[0157] [Preparation Examples 1-6] A diethylene glycol solution containing 10% by mass of compound 2 obtained in Comparative Example 1-1 was prepared. This solution was prepared by stirring at 50°C for 1 hour using a hot stirrer.

[0158] [5] Preparation of charge-transporting varnish [Example 2-1] 1.723 g of 1,3-dimethyl-2-imidazolidinone, 3.537 g of diethylene glycol, and 2.927 g of dipropylene glycol monomethyl ether were added to a sample tube and stirred with a stirrer at room temperature for 30 minutes. Then, 0.42 g of the diethylene glycol solution of polymer A obtained in Preparation Example 1-3 was added and stirred with a stirrer at room temperature for 30 minutes. Next, 0.28 g of the solution obtained in Preparation Example 1-1 was added and stirred at room temperature for 30 minutes. Furthermore, 1.113 g of the silica sol of dipropylene glycol monomethyl ether dispersion obtained in Preparation Example 1-2 was added and stirred at room temperature for 30 minutes. The resulting mixed solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a charge-transporting varnish.

[0159] [Example 2-2] 2.524 g of 1,3-dimethyl-2-imidazolidinone, 3.451 g of dipropylene glycol, and 2.443 g of dipropylene glycol monomethyl ether were added to a sample tube and stirred at room temperature for 30 minutes using a stirrer. Then, 0.21 g of the 1,3-dimethyl-2-imidazolidinone solution of polymer B obtained in Preparation Example 1-3 was added and stirred at room temperature for 30 minutes using a stirrer. Next, 0.28 g of the solution obtained in Preparation Example 1-1 was added and stirred at room temperature for 30 minutes. Furthermore, 1.113 g of silica sol of dipropylene glycol monomethyl ether dispersion obtained in Preparation Example 1-2 was added and stirred at room temperature for 30 minutes. The resulting mixed solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a charge-transporting varnish.

[0160] [Comparative Example 2-1] 2.308 g of 1,3-dimethyl-2-imidazolidinone, 3.444 g of dipropylene glycol, and 2.435 g of dipropylene glycol monomethyl ether were added to a sample tube and stirred with a stirrer at room temperature for 30 minutes. Then, 0.42 g of the 1,3-dimethyl-2-imidazolidinone solution of D-66-20BS obtained in Preparation Example 1-5 was added and stirred with a stirrer at room temperature for 30 minutes. Next, 0.28 g of the solution obtained in Preparation Example 1-1 was added and stirred at room temperature for 30 minutes. Furthermore, 1.113 g of silica sol dispersed in dipropylene glycol monomethyl ether obtained in Preparation Example 1-2 was added and stirred at room temperature for 30 minutes. The resulting mixed solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a charge-transporting varnish.

[0161] [Comparative Example 2-2] In a sample tube, 1.727 g of 1,3-dimethyl-2-imidazolidinone, 3.755 g of diethylene glycol, and 2.936 g of dipropylene glycol monomethyl ether were added and stirred with a stirrer at room temperature for 30 minutes. Then, 0.21 g of the diethylene glycol solution of compound 2 obtained in Preparation Example 1-6 was added and stirred with a stirrer at room temperature for 30 minutes. Next, 0.28 g of the solution obtained in Preparation Example 1-1 was added and stirred at room temperature for 30 minutes. Furthermore, 1.113 g of silica sol of dipropylene glycol monomethyl ether dispersion obtained in Preparation Example 1-2 was added and stirred at room temperature for 30 minutes. The resulting mixed solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a charge-transporting varnish.

[0162] [6] Evaluation of the coating properties of the upper layer The charge-transporting varnishes obtained in Example 2-1, Example 2-2, Comparative Example 2-1, and Comparative Example 2-2 were applied to an ITO substrate using a spin coater, and then dried at 120 °C for 1 minute under the atmosphere. Next, the dried ITO substrate was fired at 230 °C for 15 minutes in an air atmosphere to form a uniform 30-nm-thick charge-transporting thin film on the ITO substrate. As the ITO substrate, a 50-mm × 50-mm × 0.7-t glass substrate with a 50-nm-thick ITO film uniformly formed on the substrate surface was used, and impurities on the surface were removed by an O2 plasma cleaning device (150 W, 30 seconds) before use. 1 μL of anisole (manufactured by Tokyo Chemical Industry Co., Ltd.) was dropped onto each of the obtained thin films, and the results of measuring the contact angle are shown in Table 1.

[0163] [Table 1]

[0164] For the charge-transporting thin films obtained in Example 2-1, Example 2-2, and Comparative Example 2-2, the contact angle of anisole was less than 5°, and the wettability was good. The difference in the solids of the charge-transporting varnishes of Example 2-1, 2-2, Comparative Example 2-1, and Comparative Example 2-2 is the type of fluorinated sulfonic acid compound. It was confirmed that the charge-transporting thin films using Polymer A, Polymer B, and Compound 2 have excellent upper-layer wettability.

[0165] [7] Fabrication and property evaluation of organic EL devices [Example 3-1] The varnish obtained in Example 2-1 was applied to the same ITO substrate with impurities removed using a spin coater, and then dried at 120 °C for 1 minute under the atmosphere. Next, the dried ITO substrate was fired at 230 °C for 15 minutes in an air atmosphere to form a uniform 30-nm-thick thin film on the ITO substrate. Next, for the ITO substrate on which the thin film was formed, a vapor deposition apparatus (vacuum degree 1.0 × 10 -5Using Pa, α-NPD(N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine) was deposited at a rate of 0.2 nm / second to a thickness of 30 nm. Next, HTEB-01, an electronic block material manufactured by Kanto Chemical Co., Ltd., was deposited to a thickness of 10 nm. Subsequently, NS60, an emissive layer host material, and Ir(ppy)3, an emissive layer dopant material, manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., were co-deposited. The co-deposit was carried out by controlling the deposition rate so that the concentration of Ir(ppy)3 was 6%, resulting in a 40 nm stack. Then, thin films of Alq3, lithium fluoride, and aluminum were sequentially stacked to obtain an organic EL device. In this process, the deposition rates were 0.2 nm / second for Alq3 and aluminum, and 0.02 nm / second for lithium fluoride, resulting in film thicknesses of 20 nm, 0.5 nm, and 80 nm, respectively.

[0166] Furthermore, to prevent performance degradation due to the effects of oxygen, water, etc. in the air, the organic EL elements were sealed with a sealing substrate before their performance was evaluated. The sealing was performed using the following procedure. In a nitrogen atmosphere with an oxygen concentration of 2 ppm or less and a dew point of -76°C or less, organic EL elements were placed between encapsulating substrates, and the encapsulating substrates were bonded together with an adhesive (MORESCO Moisture Cut WB90US(P) manufactured by MORESCO Corporation). At this time, a water-repellent agent (HD-071010W-40 manufactured by Dynic Corporation) was placed inside the encapsulating substrates together with the organic EL elements. The bonded encapsulating substrates were then irradiated with UV light (wavelength: 365 nm, irradiation dose: 6,000 mJ / cm²). 2 After that, the adhesive was cured by annealing at 80°C for 1 hour.

[0167] [Example 3-2] An organic EL element was obtained by repeating the procedure of Example 3-1, except that the varnish obtained in Example 2-2 was used instead of the varnish obtained in Example 2-1.

[0168] [Comparative Example 3-1] An organic EL element was obtained by repeating the procedure of Example 3-1, except that the varnish obtained in Comparative Example 2-2 was used instead of the varnish obtained in Example 2-1.

[0169] For each of the elements obtained in Example 3-1, Example 3-2, and Comparative Example 3-1, the brightness was 10,000 cd / m². 2 The driving voltage, current density, and luminous efficiency when driven by [specific method / system], as well as the half-life of the brightness (initial brightness 10,000 cd / m²). 2 The time required for the value to reach half was measured. The results are shown in Table 2.

[0170] [Table 2]

[0171] As shown in Table 1, the organic EL elements fabricated in Examples 3-1, 3-2, and Comparative Example 3-1 all exhibit good initial characteristics. However, the elements in Example 3-1 using polymer A and Example 3-2 using polymer B show superior lifetime characteristics compared to the elements in Comparative Example 3-1 using compound 2. This is presumed to be because the increased molecular weight due to polymerization improved the heat resistance of the compounds. Furthermore, the device in Example 3-2, which uses polymer B consisting of a copolymer of compound 1 and perfluorostyrene, exhibits superior device efficiency and lifespan. This is presumed to be due to an improved proportion of fluorine atoms in the polymer, which enhances the surface modification effect of the charge-transporting thin film.

Claims

1. A charge-transporting varnish comprising a charge-transporting substance, a dopant substance consisting of a fluorinated aryl sulfonic acid polymer compound containing repeating units represented by the following formula (1), and a solvent. 【Chemistry 1】 [In the formula, Ar F represents an arylene fluoride group, X represents O, S, NH, CONH, or NHCO, and Ar S is at least one SO on the ring 3 This represents an aryl group containing an R group (where R represents a hydrogen atom or an alkali metal atom).

2. The charge-transporting varnish according to claim 1, wherein the fluorinated aryl sulfonic acid polymer compound further comprises a repeating unit represented by the following formula (2). 【Chemistry 2】 (In the formula, R' represents a monovalent organic group.)

3. The charge-transporting varnish according to claim 2, wherein R' is an aryl fluoride group.

4. The Ar F The charge-transporting varnish according to any one of claims 1 to 3, wherein the group is a perfluoroarylene group.

5. The Ar F However, the charge-transporting varnish according to claim 4, wherein the group is a tetrafluorophenylene group.

6. The Ar S However, there are two or more of the SO on the ring. 3 The charge-transporting varnish according to any one of claims 1 to 5, wherein the aryl group has an R group.

7. The above-mentioned Ar S is a naphthyl group having two or more of the above-mentioned SO 3 R groups, and the charge transport varnish according to claim 6.

8. The charge-transporting varnish according to any one of claims 1 to 7, wherein X is O.

9. The charge-transporting varnish according to any one of claims 1 to 8, wherein the charge-transporting substance is an arylamine derivative or a thiophene derivative.

10. A charge-transporting thin film obtained from a charge-transporting varnish according to any one of claims 1 to 9.

11. An electronic device comprising a charge-transporting thin film according to claim 10.

12. An organic electroluminescent element comprising a charge-transporting thin film according to claim 10.

13. The organic electroluminescent element according to claim 12, wherein the charge-transporting thin film is a hole injection layer or a hole transport layer.

14. A quantum dot light-emitting diode comprising a charge-transporting thin film according to claim 12.

15. The quantum dot light-emitting diode according to claim 14, wherein the charge-transporting thin film is a hole injection layer or a hole transport layer.

16. A fluorinated aryl sulfonic acid polymer compound characterized by containing a repeating unit represented by the following formula (1). 【Transformation 3】 [In the formula, Ar F represents an arylene fluoride group, X represents O, S, NH, CONH, or NHCO, and Ar S This is two or more SOs on the ring. 3 This represents an aryl group containing an R group (where R represents a hydrogen atom or an alkali metal atom).

17. The Ar S However, there are two or more of the SO on the ring. 3 The fluorinated aryl sulfonic acid polymer compound according to claim 16, wherein the naphthyl group has an R group.

18. The Ar s However, the following formula (Ar S -5) or formula (Ar S -6) The fluorinated aryl sulfonic acid polymer compound according to claim 17. 【Chemistry 4】 (In the formula, R represents the same meaning as above, independently.)

19. The fluorinated aryl sulfonic acid polymer compound according to any one of claims 16 to 18, wherein X is O.

20. A fluorinated aryl sulfonic acid polymer compound according to claim 19, comprising a repeating unit represented by the following formula. 【Transformation 5】

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