Fluoroaryl sulfonic acid polymer compound and use thereof

Abstract

A fluoroaryl sulfonic acid polymer compound which is characterized by containing repeating units represented by formula (1) and formula (2) and which, when used as a dopant material for an organic EL element or the like, forms a charge-transporting thin film having excellent hole injection properties and hole transport properties. [In the formula, ArF1 and ArF2 each independently represent a fluoroarylene group, X1 and X2 each independently represent O, S, NH, CONH or NHCO, and ArS represents an aryl group having at least one SO3R group on the ring (R represents a hydrogen atom or an alkali metal atom) (In the formula, R1 represents an alkyl group having 3-10 carbon atoms substituted with at least one fluorine atom, and R2 and R3 each independently represent a hydrogen atom or a methyl group. ]

Description

Technical Field

[0001] This invention relates to fluoroaryl sulfonic acid polymer compounds and their uses. Background Technology

[0002] Organic electroluminescent (hereinafter referred to as organic EL) devices use organic functional films containing organic compounds as the light-emitting layer and charge injection layer. In particular, the hole injection layer is responsible for the charge transfer between the anode and the hole transport layer. It plays an important role in achieving low-voltage driving and high brightness of organic EL devices. High hole injection performance is required for the hole transport layer formed on the upper layer.

[0003] Methods for forming hole injection layers can be broadly categorized into dry methods, such as vapor deposition, and wet methods, such as inkjet printing and spin coating. Comparing these methods, wet methods can efficiently fabricate thin films with high flatness over large areas. Therefore, with the current trend towards large-area organic EL displays, there is a need for hole injection layers that can be formed using wet methods. This paper reports on technologies related to hole injection materials that can be formed using wet methods (Patent Document 1).

[0004] Furthermore, in recent years, with the development of display technology, quantum dot electroluminescent (hereinafter referred to as quantum dot EL) devices, which use quantum dot materials as the light-emitting layer, have emerged and shown broad application prospects. These quantum dot EL devices can be manufactured at low cost using wet processes. On the other hand, due to their characteristics such as controllable emission wavelength, high color purity, high luminous efficiency, and suitability for flexible applications, they have attracted considerable attention in fields such as display technology and lighting.

[0005] The applicant has reported that, as one such technology, when using a prescribed fluoroaryl sulfonic acid polymer compound having a fluoroaryl group and an aryl group containing at least one sulfonyl group or its salt as a dopant material with a charge transport material, it is possible to achieve a thin film with excellent charge transport properties, and organic EL elements including the thin film exhibit good characteristics and excellent lifetime performance (Patent Document 2). However, there is room for further improvement in terms of hole injection and hole transport properties of the compound.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: International Publication No. 2008 / 032616

[0009] Patent Document 2: International Publication No. 2023 / 008176 Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] The present invention was made in view of the above-mentioned circumstances, and its object is to provide a fluoroaryl sulfonic acid polymer compound that forms a charge transport thin film with excellent hole injection and hole transport properties when used as a dopant material in organic EL elements, etc.

[0012] Methods for solving problems

[0013] In order to solve the above-mentioned problems, the inventors conducted repeated and in-depth research and found that a specified fluoroaryl sulfonic acid polymer with low surface energy fluoroalkyl groups has the property of being able to efficiently dopant charge transport substances near the surface of a charge transport film. Therefore, the hole injection and hole transport properties of the upper layer of the charge transport film containing the polymer are improved, resulting in improved performance of organic EL elements including the film, and thus the present invention was completed.

[0014] That is, the present invention provides:

[0015] 1. A fluoroarylsulfonic acid polymer compound, characterized in that it comprises repeating units represented by the following formula (1) and the following formula (2),

[0016] [Chemistry 1]

[0017]

[0018] In the formula, Ar F1 and Ar F2 Each independently represents a fluoroarylene group, X 1 and X 2 Each can independently represent O, S, NH, CONH or NHCO, Ar S This indicates an aryl group having at least one SO3R group on the ring, where R represents a hydrogen atom or an alkali metal atom. 1 R represents an alkyl group with 3 to 10 carbon atoms that has been substituted by at least one fluorine atom. 2 and R 3 Each can independently represent a hydrogen atom or a methyl group;

[0019] 2. The fluoroaryl sulfonic acid polymer compound according to claim 1, wherein the Ar F1 and Ar F2 It is a perfluoroaryl group;

[0020] 3. The fluoroaryl sulfonic acid polymer compound according to claim 2, wherein the Ar F1 and Ar F2 It is tetrafluorophenylene;

[0021] 4. The fluoroaryl sulfonic acid polymer compound according to any one of 1 to 3, wherein the Ar S An aryl group having two or more of the SO3R groups on a ring;

[0022] 5. The fluoroaryl sulfonic acid polymer compound according to claim 4, wherein the Ar S A naphthyl group having two or more of the SO3R groups on the ring;

[0023] 6. The fluoroaryl sulfonic acid polymer compound according to any one of 1 to 5, wherein the X 1 and X 2 It is O;

[0024] 7. A dopant material comprising a fluoroaryl sulfonic acid polymer compound according to any one of 1 to 6;

[0025] 8. A charge-transporting varnish comprising a charge-transporting substance, a dopant substance according to 7, and a solvent;

[0026] 9. The charge-transporting varnish according to claim 8, wherein the charge-transporting substance is an arylamine derivative or a thiophene derivative;

[0027] 10. A charge-transporting thin film obtained from the charge-transporting varnish according to 8 or 9;

[0028] 11. An electronic component comprising a charge-transporting thin film according to claim 10;

[0029] 12. The electronic component according to claim 11, wherein the charge transport thin film is a hole injection layer or a hole transport layer;

[0030] 13. The electronic component according to claim 11, wherein the electronic component is an organic electroluminescent element or a quantum dot electroluminescent element.

[0031] The effects of the invention

[0032] Because the fluoroaryl sulfonic acid polymer compound of the present invention has fluoroalkyl groups with low surface energy, when a charge transport film containing the polymer is formed by wet process, the polymer tends to be biased to the surface layer, which can efficiently dope the charge transport material near the surface layer. Therefore, the charge transport film containing the polymer improves the hole injection and hole transport properties of the layer formed on the upper layer.

[0033] Organic EL devices, including the charge-transport thin film of the present invention, exhibit excellent characteristics, particularly low driving voltage, high efficiency, and long lifetime.

[0034] The fluoroaryl sulfonic acid polymer compounds of the present invention, having such properties, are suitable for use as dopant materials in the manufacture of thin films for electronic components, primarily organic EL elements and quantum dot EL elements. Attached Figure Description

[0035] Figure 1 To illustrate the compound obtained in Synthesis Example 2 1 The H-NMR spectrum. Detailed Implementation

[0036] The present invention will now be described in more detail.

[0037] [1] Fluorinated aryl sulfonic acid polymer compounds

[0038] The fluoroaryl sulfonic acid polymer compound of the present invention is characterized in that it comprises repeating units represented by the following formula (1) and the following formula (2).

[0039] [Chemistry 2]

[0040]

[0041] In equations (1) and (2), Ar F1 and Ar F2 Each can be represented independently as a fluoroaryl group.

[0042] These fluorinated aryl groups are not particularly limited as long as at least one hydrogen atom on the aryl group is replaced by a fluorine atom, but preferably at least one of the remaining hydrogen atoms is replaced by an electron-withdrawing group other than a sulfonyl group.

[0043] As electron-withdrawing groups, examples include halogen atoms such as fluorine, chlorine, bromine, and iodine; nitro; cyano; acyl; carboxyl; carboxylic acid ester; and acyl groups such as formyl and acetyl.

[0044] In particular, Ar F1 and Ar F2 The fluoroarylene is preferably an arylene substituted with two or more fluorine atoms, and more preferably a perfluoroarylene.

[0045] For constituting Ar F1 and Ar F2 There is no particular limitation on the number of carbon atoms in the arylene group, but 6 to 20 carbon atoms are preferred, and 6 to 16 carbon atoms are 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, anthracene, etc., with phenylene being preferred, and 1,4-phenylene being more preferred.

[0046] Therefore, as Ar F1 and Ar F2 Tetrafluorophenylene is preferred, and 2,3,5,6-tetrafluoro-1,4-phenylene is more preferred.

[0047] X 1 and X2 Each can be independently represented as O, S, NH, CONH or NHCO, with O and S being preferred, and O being more preferred.

[0048] In equation (1), Ar S This indicates 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, preferably a hydrogen atom.

[0049] For constituting Ar S There is no particular limitation on the number of carbon atoms in the aryl group, but 6 to 30 carbon atoms are preferred, 6 to 20 carbon atoms are more preferred, and 6 to 12 carbon atoms are even more preferred. Specific examples include phenyl, 1-naphthyl, 2-naphthyl, 1-anthrayl, 2-anthrayl, 9-anthrayl, 1-phenanthyl, 2-phenanthyl, 3-phenanthyl, 4-phenanthyl, and 9-phenanthyl, with naphthyl being preferred, and 1-naphthyl being more preferred.

[0050] Additionally, Ar S The SO3R group has only one or more, preferably two to four, and more preferably two.

[0051] In equations (1) and (2), R 1 R represents an alkyl group having 3 to 10 carbon atoms, preferably 3 to 8 carbon atoms, and more preferably 3 to 6 carbon atoms, substituted by at least one fluorine atom. 2 and R 3 Each can be used independently to represent a hydrogen atom or a methyl group.

[0052] As R 1Specific examples of alkyl groups having 3 to 10 carbon atoms substituted with at least one, preferably two, more preferably three, further preferably four, and even more preferably five fluorine atoms include 3-fluoropropyl, 2-fluoropropyl, 1-fluoropropyl, 3,3-difluoropropyl, 2,2-difluoropropyl, 1,1-difluoropropyl, 3,3,3-trifluoropropyl, 2,3,3,3-tetrafluoropropyl, 2,2,3,3,3-pentafluoropropyl, perfluoropropyl, 4-fluorobutyl, 3-fluorobutyl, 2-fluorobutyl, 1-fluorobutyl, 4,4-difluorobutyl, 3,3-difluorobutyl, 2,2-difluorobutyl, 1,1-difluoropropyl, perfluoropropyl, perfluoropropyl, perfluorobutyl, 3-fluorobutyl, 2-fluorobutyl, 1,1-difluorobutyl, perfluoropropyl, perfluoropropyl, perfluorobutyl ... Fluorobutyl, 4,4,4-trifluorobutyl, 3,3,4,4,4-pentafluorobutyl, 2,2,3,3,4,4,4-heptafluorobutyl, perfluorobutyl, 5-fluoropentyl, 4-fluoropentyl, 3-fluoropentyl, 2-fluoropentyl, 1-fluoropentyl, 5,5-difluoropentyl, 4,4-difluoropentyl, 3,3-difluoropentyl, 2,2-difluoropentyl, 1,1-difluoropentyl, 5,5,5-trifluoropentyl, 4,4,5,5,5-pentafluoropentyl, 3,3,4,4,5,5,5-heptafluoropentyl, 2,2,3,3,4,4,5,5,5-nonafluoropentyl, perfluoropentyl, perfluorohexyl, perfluoroheptyl, perfluorooctyl, etc.

[0053] As a preferred unit of formula (1), units represented by the following formula (1-1) can be listed.

[0054] [Chemistry 3]

[0055]

[0056] (In the formula, n1 represents an integer from 1 to 4, R) 2 and Ar S This indicates the same meaning as above.

[0057] As a more preferred unit of formula (1), units represented by the following formulas (1-2) can be listed.

[0058] [Chemistry 4]

[0059]

[0060] (In the formula, n1 represents an integer from 1 to 4, R) 2 and Ar S This indicates the same meaning as above.

[0061] As a further preferred unit of formula (1), units represented by the following formulas (1-3) can be listed.

[0062] [Chemistry 5]

[0063]

[0064] (In the formula, Ar) S This indicates the same meaning as above.

[0065] In addition, Ar is the preferred choice S The following formulas can be listed (Ar) S -1)~(Ar S -6) represents the group.

[0066] [Chemistry 6]

[0067]

[0068] (In the formula, R represents the same meaning as above. n represents an integer from 2 to 4.)

[0069] [Chemistry 7]

[0070]

[0071] (In the formula, R represents the same meaning as above.)

[0072] [Chemistry 8]

[0073]

[0074] (In the formula, R represents the same meaning as above.)

[0075] [Chemistry 9]

[0076]

[0077] (In the formula, R represents the same meaning as above.)

[0078] As a preferred unit of formula (2), units represented by the following formula (2-1) can be listed.

[0079] [Chemistry 10]

[0080]

[0081] (In the formula, n2 represents an integer from 1 to 4, R) 1 and R 3 This indicates the same meaning as above.

[0082] As a more preferred unit of formula (2), units represented by the following formula (2-2) can be listed.

[0083] [Chemistry 11]

[0084]

[0085] (In the formula, n2 represents an integer from 1 to 4, R) 1 and R3 This indicates the same meaning as above.

[0086] As a further preferred unit of equation (2), units represented by the following equations (2-3) can be listed.

[0087] [Chemistry 12]

[0088]

[0089] (where R) 1 This indicates the same meaning as above.

[0090] In the fluoroaryl sulfonic acid polymer compound of the present invention, there is no particular limitation on the ratio of the unit of formula (1) to the unit of formula (2). If the improvement effect of hole injection and the like when used as a dopant material is taken into consideration, the molar ratio is preferably 10:1 to 1:10, more preferably 5:1 to 1:5, and even more preferably 4:1 to 1:4.

[0091] The fluoroaryl sulfonic acid polymer compound of the present invention may be a polymer containing only repeating units represented by the above formulas (1) and (2), and may further contain repeating units represented by the following formula (3) (however, excluding the units of formulas (1) and (2)).

[0092] [Chemistry 13]

[0093]

[0094] In formula (3), R' represents a monovalent organic group, R 4 It represents a hydrogen atom or a methyl group.

[0095] Examples of monovalent organic groups that can be represented by R' include monovalent hydrocarbon groups, heteroaryl groups, and -COOR" groups (where R" represents an alkyl group with 1 to 10 hydrogen atoms).

[0096] There is no particular limitation 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; and aryl groups such as phenyl, 1-naphthyl, 2-naphthyl, 1-anthrayl, 2-anthrayl, 9-anthrayl, 1-phenanthyl, 2-phenanthyl, 3-phenanthyl, 4-phenanthyl, and 9-phenanthyl.

[0097] Specific examples of heteroaryl groups include 2-thienyl, 3-thienyl, 2-furanyl, 3-furanyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 3-isooxazolyl, 4-isooxazolyl, 5-isooxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, 2-imidazolyl, 4-imidazolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, etc., which have 2 to 20 carbon atoms.

[0098] As R”, an alkyl group having 1 to 10 carbon atoms can be listed as the same group as the group exemplified above, wherein an alkyl group having 1 to 5 carbon atoms is preferred.

[0099] It should be noted that, with regard to the monovalent hydrocarbon group, heteroaryl group, and alkyl group with 1 to 10 carbon atoms of the above-mentioned, some or all of its hydrogen atoms may be replaced by substituents. Examples of such substituents include halogen atoms, cyano groups, nitro groups, carboxyl groups, sulfonyl groups, and hydroxyl groups. Examples of halogen atoms include atoms that are the same as those exemplified above.

[0100] In the case where the fluoroaryl sulfonic acid polymer compound of the present invention contains a repeating unit represented by formula (3), there is no particular limitation on its content ratio. In the fluoroaryl sulfonic acid polymer compound, it is preferred to be 0.1 to 50 mol%, more preferably 0.1 to 30 mol%, even more preferably 0.1 to 20 mol%, and even more preferably 0.1 to 10 mol%.

[0101] The molecular weight of the fluoroaryl sulfonic acid polymer compound of the present invention is not particularly limited. From the viewpoint of improving heat resistance and ensuring solubility in solvents, the weight-average molecular weight Mw is preferably 1,000 to 50,000, more preferably 1,500 to 10,000, and even more preferably 2,000 to 10,000.

[0102] In addition, the molecular weight distribution (Mw / Mn) is preferably 1 to 3, more preferably 1 to 2.

[0103] It should be noted that the weight-average molecular weight is a value obtained by gel permeation chromatography (GPC) using polyethylene oxide as a standard sample.

[0104] The fluoroaryl sulfonic acid polymer compound of the present invention can be obtained by polymerizing a monomer represented by formula (1A), a monomer represented by formula (2A), and a monomer represented by formula (3A) as needed, in the presence of a solvent and a free radical polymerization initiator using a known free radical polymerization method.

[0105] It should be noted that, at this time, the monomers represented by formula (1A) can be used in combination with more than two types, the monomers represented by formula (2A) can be used in combination with more than two types, and the monomers represented by formula (3A) can be used in combination with more than two types.

[0106] [Chemistry 14]

[0107]

[0108] (In the formula, Ar) F1 Ar F2 Ar S X 1 X 2 R 1 R 2 R 3 R 4 R' has the same meaning as above.

[0109] As a free radical polymerization initiator, it is possible to use known compounds such as free radical thermal polymerization initiators and free radical photopolymerization initiators.

[0110] Free radical thermal polymerization initiators are compounds that generate free radicals by heating to above their decomposition temperature. Examples of such free 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, dilauryl peroxide, etc.), peroxy ketals (dibutylperoxycyclohexane, etc.), alkyl peresters (tert-butyl peroxyneodecanate, tert-butyl peroxyneopentate, tert-pentyl peroxy2-ethylcyclohexanoate, etc.), persulfates (potassium persulfate, sodium persulfate, ammonium persulfate, etc.), and azo compounds (azobisisobutyronitrile, 2,2'-di(2-hydroxyethyl)azobisisobutyronitrile, etc.). Free radical thermal polymerization initiators can be used alone or in combination of two or more.

[0111] There are no particular limitations on free radical photopolymerization initiators, as long as they are compounds that initiate free radical polymerization by light irradiation. Examples of such free radical photopolymerization initiators include benzophenone, michleilone, 4,4'-bis(diethylamino)benzophenone, xanthonone, thioxanthonone, isopropyl xanthonone, 2,4-diethylthioxanthonone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylphenylacetone, 2-hydroxy-2-methyl-4'-isopropylphenylacetone, 1-hydroxycyclohexylphenyl ketone, isopropyl phenylacetoin ether, isobutyl phenylacetoin ether, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)- Butanone-1,4-dimethylaminobenzoate, isopentyl 4-dimethylaminobenzoate, 4,4'-bis(tert-butylperoxycarbonyl)benzophenone, 3,4,4'-tris(tert-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)-me-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-me-triazine, 2-(2',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-me-triazine, 2-(2'-methoxystyryl)-4,6-bis(trichloromethyl)-me-triazine, 2-(4'-pentoxy) 4,6-bis(trichloromethyl)-2,6-bis(trichloromethyl)-2,6-bis(trichloromethyl)-2,6-bis(trichloromethyl)-2,6-bis(trichloromethyl)-2,6-bis(2'-chlorophenyl ... 4',5,5'-Tetra(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-dodecylcarbazole, 1-hydroxycyclohexylphenyl ketone, bis(5-2,4-cyclopentadien-1-yl)-bis(2,6-Difluoro-3-(1H-pyrrolo-1-yl)-phenyl)titanium, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-hexylperoxycarbonyl)benzophenone, 3,3'-di(methoxycarbonyl)-4,4'-di(tert-butylperoxycarbonyl)benzophenone, 3,4'-di(methoxycarbonyl)-4,3'-di(tert-butylperoxycarbonyl)benzophenone, 4,4'-di(methoxycarbonyl)-3,3'-di(tert-butylperoxycarbonyl)benzophenone, 2-(3-methyl-3H-benzothiazol-2-ylidene)-1-naphth-2-yl-ethyl ketone, 2-(3-methyl-1,3-benzothiazol-2(3H)-ylidene)-1-(2-benzoyl)ethyl ketone, etc. Free radical photopolymerization initiators can be used alone or in combination of two or more.

[0112] As a solvent used in the polymerization reaction, there are no particular limitations as long as it is the solvent in which the resulting polymer dissolves. 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, isopropanol, methoxymethylpentanol, dipentene, ethylpentyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isopentyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, and methyl cellosolve. Ethyl carbitol acetate, ethyl carbitol 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 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 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, 1,4-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 Organic solvents such as propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diethylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, 3-methoxy-N,N-dimethylpropionamide, 3-ethoxy-N,N-dimethylpropionamide, and 3-butoxy-N,N-dimethylpropionamide.

[0113] The polymerization temperature during free radical polymerization can be any temperature from 30 to 150°C, preferably in the range of 50 to 100°C.

[0114] It should be noted that the monomer of formula (1A) can be manufactured using known methods disclosed in Patent Document 2, etc., for example, by reacting an aryl sulfonate having a hydroxyl group with a fluoroaryl compound in the presence of a base.

[0115] In addition, the monomer of formula (2A) can be obtained, for example, by reacting a fluoroalkyl alcohol with a fluoroaryl compound in the presence of a base.

[0116] [2] Charge transport varnish

[0117] The charge-transfer varnish of the present invention comprises a dopant containing the above-mentioned fluoroaryl sulfonic acid polymer compound, a charge-transfer substance, and a solvent.

[0118] It should be noted that in this invention, the term "charge transport" is synonymous with both electrical conductivity and hole transport. A "charge transport varnish" can be a substance that inherently possesses charge transport properties, or a substance whose solid film obtained using it possesses charge transport properties.

[0119] As a charge-transporting substance, there are no particular limitations, and it is possible to appropriately select from charge-transporting compounds, charge-transporting oligomers, charge-transporting polymers, etc., used in the field of organic EL, etc.

[0120] Specific examples include arylamine derivatives such as oligomeric aniline derivatives, N,N'-diarylbenzidine derivatives, and N,N,N',N'-tetraarylbenzidine derivatives; thiophene derivatives such as oligomeric thiophene derivatives, thiophenothiophene derivatives, and thiophenobenzothiophene derivatives; various charge-transporting compounds such as oligomeric pyrrole derivatives; and charge-transporting polymers such as charge-transporting oligomers, polythiophene derivatives, polyaniline derivatives, and polypyrrole derivatives, among which polythiophene derivatives and arylamine derivatives are preferred.

[0121] Furthermore, from the viewpoint of manufacturing a film with high flatness, the charge-transporting compound (low molecular weight compound) or charge-transporting oligomer, such as the arylamine compound represented by formula (H2) or (H3) described later, is preferably monodisperse (i.e., has a molecular weight distribution of 1). In this case, from the viewpoint of preparing a uniform varnish that forms a film with high flatness, the molecular weight of the charge-transporting substance is typically around 200 to 9000. From the viewpoint of obtaining a film with even better charge transport properties, it is preferably 300 or more, more preferably 400 or more. From the viewpoint of preparing a uniform varnish that forms a film with high flatness with better reproducibility, it is preferably 8000 or less, more preferably 7000 or less, further preferably 6000 or less, and even more preferably 5000 or less.

[0122] Examples of charge-transporting materials include Japanese Patent Application 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, International Publication No. 2014 / 185208, International Publication No. 2015 / 050253, International Publication No. 2015 / 137391, International Publication No. 2015 / 137395, International Publication No. 2015 / 146912, and other international publications. Substances disclosed in International Publication No. 2015 / 146965, International Publication No. 2016 / 190326, International Publication No. 2016 / 136544, International Publication No. 2016 / 204079, International Publication No. 2017 / 122649, International Publication No. 2017 / 164158, International Publication No. 2019 / 177043, International Publication No. 2020 / 027258, International Publication No. 2020 / 027261, International Publication No. 2020 / 027264, International Publication No. 2020 / 196154, International Publication No. 2020 / 203594, and International Publication No. 2020 / 241730.

[0123] In a preferred embodiment, the charge-transporting material is a polythiophene derivative or its amine adduct containing repeating units represented by formula (H1).

[0124] [Chemistry 15]

[0125]

[0126] In the formula, R 1’ and R 2’ Each of the following is independently composed of a hydrogen atom, an alkyl group having 1 to 40 carbon atoms, a fluoroalkyl group having 1 to 40 carbon atoms, an alkoxy group having 1 to 40 carbon atoms, a fluoroalkoxy group having 1 to 40 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, or -O-[ZO]. h -R e , or sulfonyl, or R 1’ and R 2’ The bonded -OYO-, where Y is an alkylene group with 1 to 40 carbon atoms that may contain ether bonds and can be substituted with sulfonyl groups, Z is an alkylene group with 1 to 40 carbon atoms that can be substituted with halogen atoms, p is an integer greater than or equal to 1, and R... e It 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.

[0127] The alkyl group having 1 to 40 carbon atoms can be any of the following: straight-chain, branched, or cyclic. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecanyl, n-eicosyl, dodecyl, triacontyl, and tetradecyl. In this invention, alkyl groups having 1 to 18 carbon atoms are preferred, and alkyl groups having 1 to 8 carbon atoms are more preferred.

[0128] As for fluoroalkyl groups with 1 to 40 carbon atoms, there is no particular limitation as long as they are alkyl groups with 1 to 40 carbon atoms formed by replacing at least one hydrogen atom on a carbon atom with 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, etc. 1,1,2-trifluoropropyl, 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, Perfluorooctyl, etc.

[0129] As an alkoxy group having 1 to 40 carbon atoms, the alkyl group can be any of the following: straight-chain, branched, or cyclic. Specific examples include methoxy, ethoxy, n-propoxy, isopropoxy, cyclopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecoxy, n-dodecoxy, n-tridecoxy, n-tetradecoxy, n-pentadecanoxy, n-hexadecoxy, n-heptadecoxy, n-octadecoxy, n-nonadecanoxy, and n-eicosyloxy.

[0130] As fluoroalkoxy groups with 1 to 40 carbon atoms, there is no particular limitation as long as 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 ...3-difluoropropoxy, 2,3-difluoropropoxy, 2,3-difluoropropoxy, 2,3-difluoropropoxy, 2,3-difluoropropoxy, 2,3-difluoropropoxy, 2,3-difluoropropoxy, 2,3-difluoropropoxy, 2,3-difluoropropoxy, Fluoropropoxy, 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, 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, perfluoropropoxy, etc.

[0131] As alkylene groups having 1 to 40 carbon atoms, they 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, heptadecanylene, octadecylene, nonadecanylene, and eicosylene.

[0132] Specific examples of aryl groups with 6 to 20 carbon atoms include phenyl, tolyl, 1-naphthyl, 2-naphthyl, 1-anthrayl, 2-anthrayl, 9-anthrayl, 1-phenanthyl, 2-phenanthyl, 3-phenanthyl, 4-phenanthyl, and 9-phenanthyl, with phenyl, tolyl, and naphthyl being preferred.

[0133] Specific examples of aryloxy groups with 6 to 20 carbon atoms include phenoxy, anthraquinone, naphthoxy, phenanthreneoxy, and fluoreneoxy.

[0134] Examples of halogen atoms include fluorine, chlorine, bromine, and iodine.

[0135] In the above formula (H1), R is preferred. 1’ and R 2’ Each is independently a hydrogen atom, a fluoroalkyl group having 1 to 40 carbon atoms, an alkoxy group having 1 to 40 carbon atoms, or a -O[C(R] group. a R b )-C(R c R d )-O] h -R e -OR f , or sulfonyl, or R 1’ and R 2’ -OYO- is formed by bonding.

[0136] R a ~R d Each of these groups 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. As specific examples of these groups, groups identical to those listed above can be enumerated.

[0137] Among them, R a ~R d Each of the following is preferred independently: hydrogen atom, alkyl group having 1 to 8 carbon atoms, fluoroalkyl group having 1 to 8 carbon atoms, or phenyl group.

[0138] R e It is 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, preferably a hydrogen atom, methyl, propyl, or butyl.

[0139] h is preferably 1 to 5, more preferably 1, 2 or 3.

[0140] R f It 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, preferably 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, more preferably -CH2CF3.

[0141] The above R 1’ Preferably, it contains hydrogen atoms or sulfonyl groups, more preferably sulfonyl groups, and R 2’ Preferably, it is an alkoxy group with 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 -OR f More preferably -O[C(R) a Rb )-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 by mutual bonding.

[0142] For example, the preferred embodiment of the present invention involves the above-mentioned polythiophene derivative containing R. 1’ It is sulfonated, R 2’ A repeating unit consisting of a group other than sulfonyl, or containing R 1’ and R 2’ Repeating units of -OYO- formed by bonding.

[0143] Preferably, the above-mentioned polythiophene derivative contains R 1’ It is sulfonated, R 2’ It is an alkoxy group with 1 to 40 carbon atoms or -O-[ZO]. h -R e Repeating units, or those containing R 1’ and R 2’ Repeating units of -OYO- formed by bonding.

[0144] More preferably, the above-mentioned polythiophene derivative contains R 1’ It is sulfonated, R 2’ -O[C(R) a R b )-C(R c R d )-O] h -R e or -OR f Repeating units.

[0145] More preferably, the above-mentioned polythiophene derivative contains R 1’ It is sulfonated, R 2’ -O[C(R) a R b )-C(R c R d )-O] h -R e Repeating units, or those containing R 1’ and R 2’ Repeating units of -OYO- formed by bonding.

[0146] More preferably, the above-mentioned polythiophene derivative contains R 1’ It is sulfonated, R2’ It is a repeating unit of -O-CH2CH2-O-CH2CH2-O-CH3, -O-CH2CH2-O-CH2CH2-OH, or -O-CH2CH2-OH, or contains R 1’ and R 2’ Repeating units of mutually bonded groups represented by the following formulas (Y1) and (Y2).

[0147] [Chemistry 16]

[0148]

[0149] As a preferred specific example of the above-mentioned polythiophene derivative, a polythiophene comprising at least one repeating unit represented by the following formulas (H1-1) to (H1-5) can be cited.

[0150] [Chemistry 17]

[0151]

[0152] Furthermore, as a preferred structure for the aforementioned polythiophene derivative, a polythiophene derivative having a structure represented by the following formula (1a) can be listed, for example. It should be noted that in the following formula, the units can be randomly bonded or bonded as block polymers.

[0153] [Chemistry 18]

[0154]

[0155] In the formula, a to d represent the molar ratio of each unit, satisfying 0≤a≤1, 0≤b≤1, 0<a+b≤1, 0≤c<1, 0≤d<1, and a+b+c+d=1.

[0156] Furthermore, the aforementioned polythiophene derivatives can be homopolymers or copolymers (statistically, including random, gradient, and block copolymers). As polymers comprising monomer A and monomer B, block copolymers include, for example, AB diblock copolymers, ABA triblock copolymers, and (AB) copolymers. k - Multiblock copolymers. Polythiophene may contain repeating units derived from other types of monomers, such as thiophene, selenene, pyrrole, furan, tellurene, aniline, arylamines, and arylene monomers (e.g., phenylene, phenylene vinylene, and fluorene).

[0157] The content of the repeating unit represented by formula (H1) in the above-mentioned polythiophene derivative is preferably more than 50 mol%, more preferably more than 80 mol%, further preferably more than 90 mol%, even more preferably more than 95 mol%, and most preferably 100 mol% of all repeating units contained in the polythiophene derivative.

[0158] Regarding the aforementioned polythiophene derivatives, depending on the purity of the initial monomer used in the polymerization, they may contain repeating units derived from impurities. The term "homopolymer" as used above refers to a polymer containing repeating units derived from a single monomer, but may also contain repeating units derived from impurities. Preferably, the aforementioned polythiophene derivatives are polymers in which substantially all repeating units are repeating units represented by the above formula (H1), more preferably polymers containing at least one repeating unit represented by formulas (H1-1) to (H1-5).

[0159] In the case where the above-mentioned polythiophene derivative contains repeating units having sulfonation groups, from the viewpoint of further improving solubility and dispersibility in organic solvents, the polythiophene derivative preferably has an amine adduct of an amine compound added to at least a portion of the sulfonation groups it contains.

[0160] Examples of amine compounds that can be used in the formation of amine adducts include monoalkylamine compounds such as methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, tert-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, 2-ethylhexylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecanylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n-nonadecanylamine, and n-eicosylamine; and aniline, toluidine, 1-naphthylamine, 2-naphthylamine, 1-anthramine, 2-anthramine, 9-anthramine, 1-phenanthreneamine, 2-phenanthreneamine, 3-phenanthreneamine, 4-phenanthreneamine, and 9- Primary amine compounds such as phenanthreneamines and other monoaryl amines; N-ethylmethylamine, N-methyl-n-propylamine, N-methylisopropylamine, N-methyl-n-butylamine, N-methyl-sec-butylamine, N-methyl-tert-butylamine, N-methylisobutylamine, diethylamine, N-ethyl-n-propylamine, N-ethylisopropylamine, N-ethyl-n-butylamine, N-ethyl-sec-butylamine, N-ethyl-tert-butylamine, dipropylamine, N-n-propylisopropylamine, N-n-propyl-n-butylamine, N-n-propyl-sec-butylamine, diisopropylamine, N-n-butylisopropylamine, N-tert-butylisopropylamine, di-n-butylamine, di-sec-butylamine, diisobutylamine, aziridine (ethyleneimine), 2 Dialkylamine compounds including 2,2-dimethylaziridine (propylidene), 2,2-dimethylaziridine, aziridine (trimethyleneimine), 2-methylaziridine, pyrrolidine, 2-methylpyrrolidine, 3-methylpyrrolidine, 2,5-dimethylpyrrolidine, piperidine, 2,6-dimethylpiperidine, 3,5-dimethylpiperidine, 2,2,6,6-tetramethylpiperidine, hexamethyleneimine, heptamethyleneimine, octamethyleneimine, etc.; dialkylamine compounds such as diphenylamine, N-phenyl-1-naphthylamine, N-phenyl-2-naphthylamine, 1,1'-dinaphthylamine, 2,2'-dinaphthylamine, 1,2'-dinaphthylamine, etc. Diarylamine compounds such as carbazole, 7H-benzo[c]carbazole, 11H-benzo[a]carbazole, 7H-dibenzo[c,g]carbazole, and 13H-dibenzo[a,i]carbazole; secondary amine compounds such as N-methylaniline, N-ethylaniline, N-n-propylaniline, N-isopropylaniline, N-n-butylaniline, N-sec-butylaniline, N-isobutylaniline, N-methyl-1-naphthylamine, N-ethyl-1-naphthylamine, N-n-propyl-1-naphthylamine, indoline, isoindoline, 1,2,3,4-tetrahydroquinoline, and 1,2,3,4-tetrahydroisoquinoline;N,N-Dimethylethylamine, N,N-Dimethyl-n-propylamine, N,N-Dimethylisopropylamine, N,N-Dimethyl-n-butylamine, N,N-Dimethyl-sec-butylamine, N,N-Dimethyl-tert-butylamine, N,N-Dimethylisobutylamine, N,N-Diethylmethylamine, N-methyl-n-propylamine, N-methyl-diisopropylamine, N-methyl-n-butylamine, N-methyl-diisobutylamine, triethylamine, N,N-Diethyl-n-butylamine, N,N-Diisopropylethylamine, N,N-Di-n-butylethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, triisobutylamine, 1-methylazacyclobutane, 1 Trialkylamine compounds such as methylpyrrolidine and 1-methylpiperidine; triarylamine compounds such as triphenylamine; alkyldiarylamine compounds such as N-methyldiphenylamine, N-ethyldiphenylamine, 9-methylcarbazole, and 9-ethylcarbazole; and dialkylarylamine compounds such as N,N-diethylaniline, N,N-di-n-propylaniline, N,N-diisopropylaniline, and N,N-di-n-butylaniline, etc., are preferred, especially tertiary amine compounds, taking into account the balance between the solubility of the amine adduct and the charge transport properties of the resulting organic functional membrane. Trialkylamine compounds are more preferred, and triethylamine is even more preferred.

[0161] Amine adducts can be obtained by adding polythiophene derivatives to the amine itself or its solution and stirring thoroughly.

[0162] In addition, the aforementioned polythiophene derivatives or their amine adducts may use substances treated with a reducing agent.

[0163] In polythiophene derivatives or their amine adducts, the chemical structure of a portion of the repeating unit constituting them sometimes becomes an oxidized form known as a "quinone structure." The term "quinone structure" is used in contrast to the term "benzene ring structure," referring to a structure where the double bonds within the aromatic ring move outward (resulting in the disappearance of the aromatic ring) and form two exocyclic double bonds conjugated with the remaining double bonds within the ring. The relationship between these two structures can be readily understood by those skilled in the art from the relationship between the structures of benzoquinone and hydroquinone. The quinone structures of repeating units in various conjugated polymers are well known to those skilled in the art. As an example, the quinone 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').

[0164] [Chemistry 19]

[0165]

[0166] (where R) 1’ and R 2’ As defined in equation (H1) above.

[0167] This quinone-type structure is generated through a process called doping reaction, in which a polythiophene derivative containing repeating units represented by the above formula (H1) undergoes an oxidation reaction with a dopant. This process generates a portion of the polythiophene derivative containing structures called "polar substructures" and "bipolar substructures" that impart charge transport properties. These structures are well known. The introduction of "polar substructures" and / or "bipolar substructures" is essential in the manufacture of organic EL devices. In fact, during the manufacturing of organic EL devices, the aforementioned doping reaction is intentionally induced during the firing process of a film formed from a charge-transporting varnish. It is believed that the polythiophene derivative contains a quinone-type structure before this doping reaction occurs because the polythiophene derivative undergoes an unintentional oxidation reaction, equivalent to the doping reaction, during its manufacturing process (especially the sulfonation step).

[0168] The amount of quinone structure in the aforementioned polythiophene derivatives is correlated with their solubility and dispersibility in organic solvents; an increase in the amount of quinone structure tends to decrease their solubility and dispersibility. Therefore, the introduction of quinone structure after the formation of a film from a charge-transfer varnish no longer poses a problem. However, if an excessive amount of quinone structure is introduced into the polythiophene derivative through the aforementioned unintentional oxidation reaction, it can sometimes hinder the manufacture of the charge-transfer varnish. It is known that there are deviations in the solubility and dispersibility of polythiophene derivatives in organic solvents, and one reason for this is believed to be the variation in the amount of quinone structure introduced into the polythiophene through the aforementioned unintentional oxidation reaction, depending on the manufacturing conditions of each polythiophene derivative.

[0169] Therefore, if the above-mentioned polythiophene derivatives are subjected to reduction treatment using a reducing agent, even if an excessive amount of quinone structure is introduced into the polythiophene derivatives, the quinone structure is reduced by reduction, and the solubility and dispersibility of the polythiophene derivatives in organic solvents are improved. Thus, it is possible to stably manufacture a varnish with good charge transport properties that forms a film with excellent uniformity.

[0170] Regarding the conditions for reduction treatment, there are no particular limitations as long as the above-mentioned quinone structure can be reduced and appropriately converted into a non-oxidized structure, that is, the above-mentioned benzene ring structure (for example, in a polythiophene derivative containing a repeating unit represented by the above formula (H1), the quinone structure represented by the above formula (H1') can be converted into the structure represented by the above formula (H1)). For example, the treatment can be carried out simply by contacting the polythiophene derivative or amine adduct with a reducing agent, with or without a suitable solvent.

[0171] As for reducing agents like these, there are no particular limitations as long as the reduction is carried out properly. For example, commercially available ammonia and hydrazine are suitable.

[0172] Furthermore, the amount of reducing agent varies depending on the amount of reducing agent used, so it cannot be generally specified that relative to 100 parts by mass of the polythiophene derivative or amine adduct to be treated, it is generally 0.1 parts by mass or more from the viewpoint of proper reduction, and 10 parts by mass or less from the viewpoint of not leaving excessive reducing agent residue.

[0173] As an example of a specific reduction treatment method, the polythiophene derivative and amine adduct were stirred overnight at room temperature in 28% ammonia water. Through this relatively mild reduction treatment, the solubility and dispersibility of the polythiophene derivative and amine adduct in organic solvents were significantly improved.

[0174] In the charge-transporting varnish of the present invention, when using an amine adduct of a polythiophene derivative, the above-mentioned reduction treatment can be performed before or after the formation of the amine adduct.

[0175] It should be noted that this reduction treatment alters the solubility and dispersibility of the polythiophene derivative or its amine adduct in the solvent. As a result, sometimes polythiophene derivatives or their amine adducts that were not dissolved in the reaction system at the beginning of the treatment dissolve at the end. In such cases, adding an organic solvent incompatible with the polythiophene derivative or its amine adduct (such as acetone or isopropanol in the case of sulfonated polythiophene) to the reaction system generates a precipitate of the polythiophene derivative or its amine adduct. This precipitate can then be recovered by methods such as filtration.

[0176] The weight-average molecular weight of the polythiophene derivative or its amine adduct containing the 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. By setting the weight-average molecular weight above the lower limit, good electrical conductivity is obtained with good reproducibility; by setting it below the upper limit, solubility in solvents is improved. It should be noted that this weight-average molecular weight is a polystyrene equivalent using GPC.

[0177] The polythiophene derivative or its amine adduct contained in the charge-transporting varnish used in this invention may be a single polythiophene derivative or its amine adduct containing repeating units represented by formula (H1), or it may be two or more.

[0178] Furthermore, the polythiophene derivative containing the repeating unit represented by formula (H1) can be a commercially available product, or a product polymerized using a known method with thiophene derivatives as starting materials. In either case, it is preferable to use a substance refined by methods such as reprecipitation or ion exchange. By using a refined substance, the characteristics of the organic EL element having the film obtained by the charge-transfer varnish of the present invention can be further improved.

[0179] It should be noted that sulfonation of conjugated polymers and sulfonated conjugated polymers (including sulfonated polythiophene) are described in U.S. Patent No. 8,017,241 to Seshadri et al. Additionally, sulfonated polythiophene is described in International Publications Nos. 2008 / 073149 and 2016 / 171935.

[0180] It should be noted that 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 below.

[0181] In this invention, when using a polythiophene derivative or its amine adduct containing a repeating unit represented by formula (H1), as a charge transporting substance, the polythiophene derivative or its amine adduct and a charge transporting substance containing other charge transporting compounds may be used together, but preferably only the polythiophene derivative or its amine adduct containing a repeating unit represented by formula (H1) is used.

[0182] 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 generally appropriately determined in the solid component in the range of 0.05 to 40% by mass, preferably 0.1 to 35% by mass, taking into account the required film thickness, viscosity of the varnish, etc.

[0183] Another preferred option for charge-transporting materials includes substances represented by the following formulas (H2) and (H3).

[0184] [Chemistry 20]

[0185]

[0186] It should be noted that the aniline derivative represented by formula (H2) can be an oxidized aniline derivative (quinone diimine derivative) having a quinone diimine structure represented by the following formula within its molecule. As a method for oxidizing aniline derivatives to prepare quinone diimine derivatives, the methods described in International Publication No. 2008 / 010474 and International Publication No. 2014 / 119782 are examples.

[0187] [Chemistry 21]

[0188]

[0189] In formula (H2), R 1a ~R 6a Each can independently represent a hydrogen atom, halogen atom, nitro group, cyano group, amino group, and can be represented by Z. 1 Substituted alkyl groups having 1 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, or alkynyl groups having 2 to 20 carbon atoms, which can be Z 2 Substituted aryl groups with 6 to 20 carbon atoms or heteroaryl groups with 2 to 20 carbon atoms, -NHY 1 -NY 2 Y 3 -OY 4 、or -SY 5 Base, Y 1 ~Y 5 Each can be independently represented by Z 1 Substituted alkyl groups having 1 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, or alkynyl groups having 2 to 20 carbon atoms, or groups that can be substituted by Z 2 Substituted aryl groups with 6 to 20 carbon atoms or heteroaryl groups with 2 to 20 carbon atoms, Z 1 This indicates a halogen atom, nitro group, cyano group, amino group, or that can be represented by Z. 3 Substituted aryl groups with 6 to 20 carbon atoms or heteroaryl groups with 2 to 20 carbon atoms, Z 2 This indicates a halogen atom, nitro group, cyano group, amino group, or that can be represented by Z. 3 Substituted alkyl groups having 1 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, or alkynyl groups having 2 to 20 carbon atoms, Z 3 Represents a halogen atom, nitro group, cyano group, or amino group, where k and l are each independent integers from 1 to 5.

[0190] In formula (H3), R 7a ~R 10a Each group independently represents a hydrogen atom, halogen atom, nitro group, cyano group, hydroxyl group, thiol group, phosphate group, sulfonyl group, carboxyl group, and can be represented by Z. 1 Substituted alkoxy groups with 1 to 20 carbon atoms, thioalkoxy groups with 1 to 20 carbon atoms, alkyl groups with 1 to 20 carbon atoms, alkenyl groups with 2 to 20 carbon atoms, or alkynyl groups with 2 to 20 carbon atoms, which can be Z 2 Substituted aryl group with 6 to 20 carbon atoms, or aralkyl group with 7 to 20 carbon atoms, or acyl group with 1 to 20 carbon atoms, R 11a ~R 14aEach of these groups independently represents a hydrogen atom, phenyl, naphthyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, furanyl, pyrroleyl, pyrazolyl, imidazoleyl, thiopheneyl (these groups may be substituted by a halogen atom, nitro, cyano, hydroxyl, thiol, phosphate, sulfonyl, carboxyl, alkoxy group with 1 to 20 carbon atoms, thioalkoxy group with 1 to 20 carbon atoms, alkyl group with 1 to 20 carbon atoms, haloalkyl group with 1 to 20 carbon atoms, alkenyl group with 2 to 20 carbon atoms, alkynyl group with 2 to 20 carbon atoms, aryl group with 6 to 20 carbon atoms, aralkyl group with 7 to 20 carbon atoms, or acyl group with 1 to 20 carbon atoms), or a group represented by formula (H3a) (however, R 11a ~R 14a At least one of them is a hydrogen atom. ), m represents an integer from 2 to 5. Z 1 and Z 2 It means the same as above.

[0191] [Chemistry 22]

[0192]

[0193] In formula (H3a), R 15a ~R 18a Each group independently represents a hydrogen atom, halogen atom, nitro group, cyano group, hydroxyl group, thiol group, phosphate group, sulfonyl group, carboxyl group, and can be represented by Z. 1 Substituted alkoxy groups with 1 to 20 carbon atoms, thioalkoxy groups with 1 to 20 carbon atoms, alkyl groups with 1 to 20 carbon atoms, alkenyl groups with 2 to 20 carbon atoms, or alkynyl groups with 2 to 20 carbon atoms, which can be Z 2 Substituted aryl group with 6 to 20 carbon atoms, or aralkyl group with 7 to 20 carbon atoms, or acyl group with 1 to 20 carbon atoms, R 19a and R 20a Each group independently represents phenyl, naphthyl, anthracene, pyridyl, pyrimidinyl, pyridazinyl, furanyl, pyrroleyl, pyrazolyl, imidazoleyl, thiopheneyl (these groups can bond together to form a ring; additionally, they can be substituted by halogen atoms, nitro, cyano, hydroxyl, thiol, phosphate, sulfonyl, carboxyl, alkoxy group with 1-20 carbon atoms, thioalkoxy group with 1-20 carbon atoms, alkyl group with 1-20 carbon atoms, haloalkyl group with 1-20 carbon atoms, alkenyl group with 2-20 carbon atoms, alkynyl group with 2-20 carbon atoms, aryl group with 6-20 carbon atoms, aralkyl group with 7-20 carbon atoms, or acyl group with 1-20 carbon atoms). Z 1 and Z 2 It means the same as above.

[0194] Among the above formulas, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. can be listed as halogen atoms.

[0195] As an alkyl group having 1 to 20 carbon atoms, it can be any of the following: straight-chain, branched, or cyclic. Examples include straight-chain or branched alkyl groups having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl; and cyclic alkyl groups having 3 to 20 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, dicyclobutyl, dicyclopentyl, dicyclohexyl, dicycloheptyl, dicyclooctyl, dicyclononyl, and dicyclodecyl.

[0196] Specific examples of alkenyl groups with 2 to 20 carbon atoms include vinyl, n-1-propenyl, n-2-propenyl, 1-methylvinyl, n-1-butenyl, n-2-butenyl, n-3-butenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, 1-ethylvinyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, n-1-pentenyl, n-1-decenyl, and n-1-eicoseneyl.

[0197] Specific examples of alkynyl groups with 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-decynyl, n-1-pentadecanynyl, and n-1-eicosynyl.

[0198] Specific examples of aryl groups with 6 to 20 carbon atoms include phenyl, 1-naphthyl, 2-naphthyl, 1-anthrayl, 2-anthrayl, 9-anthrayl, 1-phenanthyl, 2-phenanthyl, 3-phenanthyl, 4-phenanthyl, and 9-phenanthyl.

[0199] Specific examples of aralkyl groups with 7 to 20 carbon atoms include benzyl, phenylethyl, phenylpropyl, naphthylmethyl, naphthylethyl, and naphthylpropyl.

[0200] Specific examples of heteroaryl groups with 2 to 20 carbon atoms include 2-thienyl, 3-thienyl, 2-furanyl, 3-furanyl, 2-oxazolyl, 4-oxazolyl, 5-oxazolyl, 3-isooxazolyl, 4-isooxazolyl, 5-isooxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, 2-imidazolyl, 4-imidazolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, etc.

[0201] As a haloalkyl group having 1 to 20 carbon atoms, examples include groups in which at least one hydrogen atom of the alkyl group having 1 to 20 carbon atoms is replaced by a halogen atom, wherein fluoroalkyl groups are preferred, and perfluoroalkyl groups are more preferred.

[0202] 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, undecylfluoropentyl, 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-undecylfluorohexyl, 2,2,3,3,4,4,5,5,6,6-decafluorohexyl, and 3,3,4,4,5,5,6,6,6-nonafluorohexyl.

[0203] Specific examples of alkoxy groups with 1 to 20 carbon atoms include methoxy, ethoxy, n-propoxy, isopropoxy, cyclopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecoxy, n-dodecoxy, n-tridecoxy, n-tetradecoxy, n-pentadecanoxy, n-hexadecoxy, n-heptadecoxy, n-heptadecoxy, n-octadecoxy, n-nonadecanoxy, and n-eicosyloxy.

[0204] Specific examples of thioalkoxy groups (alkathioyl groups) with 1 to 20 carbon atoms include methylthioyl, ethylthioyl, n-propylthioyl, isopropylthioyl, n-butylthioyl, isobutylthioyl, sec-butylthioyl, tert-butylthioyl, n-pentanethioyl, n-hexanethioyl, n-heptanethioyl, n-octanethioyl, n-nonanethioyl, n-decanethioyl, n-undecanethioyl, n-dodecanethioyl, n-tetanethioyl, n-tetradecanethioyl, n-pentadecanthioyl, n-hexadecanethioyl, n-heptadecanethioyl, n-octadecanethioyl, n-nonadecanthioyl, and n-eicosethioyl.

[0205] Specific examples of acyl groups with 1 to 20 carbon atoms include formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, isovaleryl, benzoyl, etc.

[0206] In equation (H2), R 1a ~R 6a Preferred hydrogen atoms, halogen atoms, and those that can be Z 1 Alkyl groups with 1 to 20 carbon atoms that can be substituted, and can be Z 2 The substituted aryl group with 6 to 20 carbon atoms, -NHY 1 -NY 2 Y 3-OY 4 、or -SY 5 In this case, Y 1 ~Y 5 Z is preferred 1 The substituted alkyl group having 1 to 10 carbon atoms or that can be Z 2 The aryl group with 6 to 10 carbon atoms that are substituted is more preferably Z 1 The substituted alkyl group having 1 to 6 carbon atoms or can be Z 2 The substituted phenyl group is more preferably an alkyl or phenyl group having 1 to 6 carbon atoms.

[0207] In particular, R 1a ~R 6a More preferably, hydrogen atom, fluorine atom, methyl, phenyl or diphenylamino (Y 2 and Y 3 -NY of phenyl 2 Y 3 Further optimization of R 1a ~R 4a It is a hydrogen atom and R 5a and R 6a It can be either a hydrogen atom or a diphenylamino atom.

[0208] In particular, in R 1a ~R 6a and Y 1 ~Y 5 In the middle, Z 1 Preferred halogen atoms or those that can be Z 3 The substituted aryl group having 6 to 10 carbon atoms, more preferably a fluorine atom or a phenyl group, and even more preferably none (i.e., an unsubstituted group), in addition, Z 2 Preferred halogen atoms or those that can be Z 3 The substituted alkyl group having 1 to 10 carbon atoms is preferred, more preferably a fluorine atom or an alkyl group having 1 to 6 carbon atoms, and even more preferably none (i.e., an unsubstituted group).

[0209] In addition, Z 3 Halogen atoms are preferred, fluorine atoms are more preferred, and the absence of halogen atoms is even more preferred (i.e., unsubstituted groups).

[0210] From the viewpoint of improving the solubility of the aniline derivative represented by formula (H2), k+l≤8 is preferred, and k+l≤5 is more preferred.

[0211] In formula (H3), R 7a ~R 10a The preferred atoms are hydrogen atoms, halogen atoms, alkyl groups having 1 to 4 carbon atoms, perfluoroalkyl groups having 1 to 4 carbon atoms, and alkoxy groups having 1 to 4 carbon atoms, with hydrogen atoms being more preferred.

[0212] Furthermore, if improving the solubility of the aniline derivative represented by formula (H3) in the solvent is considered, while simultaneously improving the uniformity of the resulting film, then R is preferred. 11a and R 13a Both are hydrogen atoms.

[0213] In particular, R is preferred. 11a and R 13a Both are hydrogen atoms, R 12a and R 14a Each group is independently a phenyl group (which may be substituted with a halogen atom, nitro group, cyano group, hydroxyl group, thiol group, phosphate group, sulfonyl group, carboxyl group, alkoxy group with 1 to 20 carbon atoms, thioalkoxy group with 1 to 20 carbon atoms, alkyl group with 1 to 20 carbon atoms, haloalkyl group with 1 to 20 carbon atoms, alkenyl group with 2 to 20 carbon atoms, alkynyl group with 2 to 20 carbon atoms, aryl group with 6 to 20 carbon atoms, aralkyl group with 7 to 20 carbon atoms, or acyl group with 1 to 20 carbon atoms), or a group represented by the above formula (H3a), more preferably R. 11a and R 13a Both are hydrogen atoms, R 12a and R 14a Each is independently phenyl, or R 19a′ and R 20a′ All are phenyl groups represented by the following formula (H3a′), with R being more preferred. 11a and R 13a Both are hydrogen atoms, R 12a and R 14a Both are phenyl.

[0214] Furthermore, when considering the ease of obtaining the compound, the ease of manufacturing, and the cost, 2 to 4 are preferred as m. When considering improving the solubility in the solvent, 2 or 3 are more preferred. When considering the balance between the ease of obtaining the compound, the ease of manufacturing, the manufacturing cost, the solubility in the solvent, and the transparency of the obtained film, 2 is the most preferred.

[0215] [Chemistry 23]

[0216]

[0217] The aniline derivatives represented by formulas (H2) and (H3) can be commercially available products or substances manufactured using known methods such as those described in the aforementioned publications. However, in either case, it is preferable to use substances refined by recrystallization, vapor deposition, or other methods prior to the preparation of the charge-transfer varnish. By using refined substances, the characteristics of electronic components possessing the thin film obtained from the varnish can be further improved. In the case of recrystallization refining, solvents such as 1,4-dioxane and tetrahydrofuran can be used.

[0218] In this invention, as a charge-transporting substance represented by formulas (H2) and (H3), one of the compounds selected from the compounds represented by formulas (H2) and (H3) can be used alone (i.e., the dispersion of the molecular weight distribution is 1), or two or more compounds can be used in combination.

[0219] Specific examples of charge-transporting substances represented by formulas (H2) and (H3) that are preferably used in this invention include the following substances, but are not limited to these.

[0220] [Chemistry 24]

[0221]

[0222] Furthermore, in this invention, aniline derivatives represented by the following formula can also be preferably used as charge transport substances.

[0223] [Chemistry 25]

[0224]

[0225] (In the formula, DPA represents diphenylamino.)

[0226] In the charge-transporting varnish of the present invention, the amount of the fluoroaryl sulfonic acid polymer compound used as a dopant is preferably about 0.1 to 10.0 by mass ratio relative to the charge-transporting substance 1 such as polythiophene derivative and arylamine derivative, and more preferably about 0.2 to 5.0.

[0227] It should be noted that the charge-transfer varnish of the present invention may contain known organic dopants and inorganic dopants in addition to fluoroaryl sulfonic acid polymer compounds, but preferably does not contain these other dopants.

[0228] As the solvent used in preparing the charge-transporting varnish of the present invention, a highly polar solvent that can readily dissolve the charge-transporting substance, dopant, etc., can be used. Alternatively, a low-polarity solvent can be used where it offers superior process suitability compared to a highly polar solvent, depending on the need. In the present invention, a low-polarity solvent is defined as a solvent with a relative permittivity of less than 7 at a frequency of 100 kHz, and a highly polar solvent is defined as a solvent with a relative permittivity of 7 or more at a frequency of 100 kHz.

[0229] Examples of low-polarity solvents include chlorine-based solvents such as chloroform and chlorobenzene; aromatic hydrocarbon-based solvents such as toluene, xylene, tetrahydronaphthalene, cyclohexylbenzene, and decylbenzene; aliphatic alcohol-based 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; and ester-based solvents such as methyl benzoate, ethyl benzoate, butyl benzoate, isoamyl benzoate, di(2-ethylhexyl) phthalate, dibutyl maleate, dibutyl oxalate, hexyl acetate, diethylene glycol monoethyl ether acetate, and diethylene glycol monobutyl ether acetate.

[0230] In addition, examples of highly polar solvents include amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylisobutyramide, N-methylpyrrolidone, and 1,3-dimethyl-2-imidazolinone; ketone solvents such as ethyl methyl ketone, isophorone, and cyclohexanone; cyano solvents such as acetonitrile and 3-methoxypropionitrile; polyol 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; and sulfoxide solvents such as dimethyl sulfoxide.

[0231] Furthermore, the charge-transporting varnish of the present invention may contain one or more metal oxide nanoparticles. Nanoparticles refer to particles with an average primary particle size of nanometer scale (typically below 500 nm). Metal oxide nanoparticles refer to metal oxides shaped into nanoparticles.

[0232] The primary particle size of the metal oxide nanoparticles is not particularly limited as long as it is nanometer-sized, preferably 2–150 nm, more preferably 3–100 nm, and even more preferably 5–50 nm. It should be noted that the particle size is the value measured using a nitrogen adsorption isotherm obtained by the BET method.

[0233] The metals that make up the above-mentioned metal oxide nanoparticles include not only metals in the usual sense, but also half-metals.

[0234] The metal is used in the general sense and is not particularly limited, but it is preferred to use one or more of the following: tin (Sn), titanium (Ti), aluminum (Al), zirconium (Zr), zinc (Zn), niobium (Nb), tantalum (Ta), and tungsten (W).

[0235] On the other hand, the term "semi-metal" refers to an element whose chemical and / or physical properties are intermediate between those of a metal and a nonmetal. A universal definition of semi-metal has not yet been established, but in this invention, the six elements boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), and tellurium (Te) are considered semi-metals. These semi-metals can be used individually, in combination of two or more, or in combination with metals in the conventional sense.

[0236] Specifically, the metal oxide nanoparticles preferably comprise 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). It should be noted that when there is a combination of two or more metals, the metal oxide can be a mixture of oxides of individual metals or a composite oxide containing multiple metals.

[0237] Specific examples of metal oxides include B2O3, B2O, SiO2, SiO, GeO2, GeO, As2O4, As2O3, As2O5, Sb2O3, Sb2O5, TeO2, SnO2, SnO, ZrO2, Al2O3, ZnO, etc., with B2O3, B2O, SiO2, SiO, GeO2, GeO, As2O4, As2O3, As2O5, SnO2, SnO, Sb2O3, TeO2, and mixtures thereof being preferred, and SiO2 being more preferred.

[0238] There is no particular limitation on the amount of metal oxide nanoparticles. From the viewpoint of improving the transparency of the obtained film and improving the uniformity of the film, the lower limit of the solid component 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.

[0239] In particular, in this invention, silica sol in which SiO2 nanoparticles are dispersed in a dispersion medium is preferably used as the metal oxide nanoparticles.

[0240] There are no particular limitations on the silica sol used; it is possible to select and use an appropriate one from known silica sols.

[0241] Commercially available silica sols are typically in the form of dispersions. Examples of commercially available silica sols include sols 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.

[0242] Specific examples of commercially available silica sols include water-dispersible silica sols such as Snowtex (registered trademark) ST-O, ST-OS, ST-O-40, ST-OL manufactured by Nissan Chemical Co., Ltd., and SILICADOL 20, 30, 40 manufactured by Nippon Chemical Industry Co., Ltd.; and organic silica 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 Co., Ltd., but are not limited to these.

[0243] In addition, there is no particular limitation on the concentration of solid components of silica sol, preferably 5 to 60% by mass, more preferably 10 to 50% by mass, and even more preferably 15 to 30% by mass.

[0244] Regarding the amount of silica sol used, the concentration is appropriately determined such that the amount of silica ultimately contained in the charge-transfer varnish becomes the amount of the aforementioned metal oxide nanoparticles.

[0245] Furthermore, regarding the charge-transporting varnish of the present invention, when the obtained film is used as a hole injection layer for organic EL devices, an organosilane compound may be included to improve the injection capability of the hole transport layer and the lifetime characteristics of the device. Its content is typically about 1 to 30% by mass relative to the total mass of the charge-transporting material and the dopant material.

[0246] Organosilanes include dialkoxysilanes, trialkoxysilanes, and tetraalkoxysilanes.

[0247] The viscosity of the charge-transfer varnish is appropriately determined based on factors such as the thickness of the film being produced and the concentration of solid components, and is typically 1–50 mPa·s at 25°C. It should be noted that, in this invention, "solid components" refers to components other than the solvent contained in the charge-transfer varnish.

[0248] In addition, the concentration of solid components in the charge-transfer varnish is appropriately determined by taking into account the viscosity and surface tension of the varnish, the thickness of the film to be produced, etc., and is usually about 0.1 to 10.0% by mass. If the coating properties of the varnish are to be improved, it is preferably about 0.5 to 5.0% by mass, and more preferably about 1.0 to 3.0% by mass.

[0249] There are no particular limitations on the preparation method of charge-transporting varnish. For example, methods include dissolving charge-transporting substances and dopant substances in a highly polar solvent, adding a low-polarity solvent and surface-treated metal oxide nanoparticles therein; or mixing a highly polar solvent and a low-polarity solvent, dissolving the charge-transporting substances and dopant substances therein, and then adding surface-treated metal oxide nanoparticles.

[0250] In particular, when preparing charge-transporting varnishes, from the viewpoint of obtaining films with better reproducibility and higher flatness, it is preferable to dissolve the charge-transporting substances, dopants, etc. in an organic solvent and then filter them using a submicron-sized filter or the like.

[0251] Regarding the charge-transporting varnish described above, by using it, charge-transporting thin films can be easily manufactured, and therefore it is suitable for use in the manufacture of electronic components, especially organic EL components and quantum dot EL components.

[0252] In this case, the charge-transporting thin film can be formed by coating and firing the aforementioned charge-transporting varnish onto a substrate.

[0253] There are no particular limitations on the application method of varnish. Examples include dip coating, spin coating, transfer printing, roller coating, brush coating, inkjet coating, spray coating, and slot coating. It is preferable to adjust the viscosity and surface tension of the varnish according to the application method.

[0254] Furthermore, there are no particular limitations on the firing atmosphere of the coated charge-transfer varnish. Not only atmospheric atmosphere, but also in inactive gases such as nitrogen and vacuum can produce thin films with uniform film formation surface and high charge transferability. Depending on the type of dopant used, by firing the varnish in an atmospheric atmosphere, a charge-transfer film can sometimes be obtained with good reproducibility.

[0255] Regarding the firing temperature, it is appropriately determined in the range of about 100 to 260°C, taking into account the intended use of the obtained film, the degree of charge transport properties imparted to the obtained film, the type of solvent, boiling point, etc. For example, when the obtained film is used as a hole injection layer of an organic EL element, it is preferable to be about 140 to 250°C, more preferably about 145 to 240°C. However, when the above-mentioned arylamine compound is used as a charge transport material, even low-temperature firing at temperatures below 200°C can yield a film with good charge transport properties.

[0256] It should be noted that during firing, in order to exhibit higher uniformity of film formation or to carry out a reaction on the substrate, two or more temperature changes can be applied. Heating can be carried out using appropriate equipment such as hot plates or ovens.

[0257] There is no particular limitation on the film thickness of the charge transport thin film. When it is used as a functional layer between the anode and the light-emitting layer, such as a hole injection layer, hole transport layer, or hole injection transport layer in organic EL elements or quantum dot EL elements, a thickness of 5 to 300 nm is preferred. As a method to vary the film thickness, there are methods such as changing the concentration of solid components in the varnish or changing the amount of solution on the substrate during coating.

[0258] [3] Organic EL devices and quantum dot EL devices

[0259] When the above-described charge-transfer thin film is applied to organic EL devices or quantum dot EL devices, it is possible to fabricate a structure in which the above-described charge-transfer thin film is included between a pair of electrodes constituting these devices.

[0260] Representative configurations of organic EL devices and quantum dot EL devices include (a) to (f) below, but are not limited to these. It should be noted that, in the following configurations, 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, as needed. 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. Moreover, arbitrary functional layers may be provided between the layers as needed.

[0261] (a) Anode / Hole Injection Layer / Hole Transport Layer / Light Emitting Layer / Electron Transport Layer / Electron Injection Layer / Cathode

[0262] (b) Anode / Hole Injection Layer / Hole Transport Layer / Light Emitting Layer / Electron Injection Transport Layer / Cathode

[0263] (c) Anode / hole injection transport layer / light-emitting layer / electron transport layer / electron injection layer / cathode

[0264] (d) Anode / hole injection transport layer / light-emitting layer / electron injection transport layer / cathode

[0265] (e) Anode / hole injection layer / hole transport layer / light emission layer / cathode

[0266] (f) Anode / hole injection transport layer / light-emitting layer / cathode

[0267] "Hole injection layer," "hole transport layer," and "hole injection transport layer" are layers formed between the light-emitting layer and the anode, which function to transport holes from the anode to the light-emitting layer. When only one layer of hole-transporting material is placed between the light-emitting layer and the anode, it is called a "hole injection transport layer." When two or more layers of hole-transporting material are placed between the light-emitting layer and the anode, the layer closest to the anode is the "hole injection layer," and all other layers are "hole transport layers." In particular, the hole injection (transport) layer uses a thin film that exhibits excellent hole acceptance not only from the anode but also excellent hole injection performance into the hole transport (light-emitting) layer.

[0268] "Electron injection layer", "electron transport layer" and "electron injection transport layer" are layers formed between the light-emitting layer and the cathode, which have the function of transporting electrons from the cathode to the light-emitting layer. When only one layer of electron transport material is provided between the light-emitting layer and the cathode, it is called "electron injection transport layer". When two or more layers of electron transport 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 "electron transport layers".

[0269] The "light-emitting layer" is an organic layer with light-emitting function. In the case of a doped system, it comprises a host material and a dopant material. In this case, the host material primarily functions to promote the recombination of electrons and holes and to encapsulate excitons within the light-emitting layer, while the dopant material enables the excitons obtained through recombination to emit light efficiently. In the case of phosphorescent devices, the host material primarily functions to encapsulate excitons generated by the dopant within the light-emitting layer.

[0270] The charge transport thin film of the present invention can be used as a functional layer disposed between the anode and the light-emitting layer in organic EL elements and quantum dot EL elements, preferably as a hole injection layer, hole transport layer, or hole injection and transport layer, more preferably as a hole injection layer or hole transport layer, and even more preferably as a hole injection layer.

[0271] The following are examples of materials and manufacturing methods used when making EL elements using the charge-transfer varnish of the present invention, but are not limited to these.

[0272] An example of a method for manufacturing an OLED element having a hole injection layer comprising a thin film obtained by the charge-transporting varnish of the present invention is described below. It should be noted that, regarding the electrodes, it is preferable to perform surface treatments such as cleaning with alcohol, pure water, UV ozone treatment, or oxygen-plasma treatment beforehand, within a range that does not adversely affect the electrodes.

[0273] On an anode substrate, a hole injection layer comprising the charge transport thin film of the present invention is formed using the method described above. This layer is then introduced into a vacuum evaporation apparatus, where a hole transport layer, a light-emitting layer, an electron transport layer, an electron transport layer / hole blocking layer, an electron injection layer, and a cathode metal are sequentially deposited by evaporation. Alternatively, instead of evaporation to form the hole transport layer and the light-emitting layer, a hole transport layer forming composition comprising a hole transport polymer and a light-emitting layer forming composition comprising a light-emitting polymer are used to form these layers by a wet process. It should be noted that, if necessary, an electron blocking layer may be provided between the light-emitting layer and the hole transport layer.

[0274] Examples of anode materials include transparent electrodes such as indium tin oxide (ITO) and indium zinc oxide (IZO), metal anodes composed of metals such as aluminum, and their alloys, with anode materials that have undergone planarization treatment being preferred. Polythiophene derivatives and polyaniline derivatives with high charge transport properties can also be used.

[0275] It should be noted that other metals that can constitute a metal anode include gold, silver, copper, indium, and their alloys, but are not limited to these.

[0276] Materials that can form the hole transport layer include triarylamine derivatives, [(triphenylamine)dimer]spirodimers, N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (α-NPD), 4,4',4”-tris[3-methylphenyl(phenyl)amino]triphenylamine (m-MTDATA), 4,4',4”-tris[1-naphthyl(phenyl)amino]triphenylamine (1-TNATA), and oligothiophenes such as 5,5”-bis-{4-[bis(4-methylphenyl)amino]phenyl}-2,2':5',2”-terthiophene (BMA-3T).

[0277] Materials that form the luminescent layer include metal complexes such as aluminum complexes of 8-hydroxyquinoline, metal complexes of 10-hydroxybenzo[h]quinoline, bis(styrene)benzene derivatives, bis(styrene)arylene derivatives, metal complexes of (2-hydroxyphenyl)benzothiazole, thiophene derivatives, and other low-molecular-weight luminescent materials; systems formed by mixing polymers such as poly(p-phenylacetylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylacetylene], poly(3-alkylthiophene), and polyvinylcarbazole with luminescent materials and electron-moving materials, but are not limited to these.

[0278] In addition, when the light-emitting layer is formed by vapor deposition, it can be co-deposited with a light-emitting dopant. Examples of light-emitting dopant include metal complexes such as tris(2-phenylpyridine)iridium(III) (Ir(ppy)3), tetraphenyl derivatives such as rubrene, quinacridone derivatives, perylene and other fused polycyclic aromatic rings, but it is not limited to these.

[0279] Materials that can form electron transport layers / hole blocking layers include, but are not limited to, oxadiazole derivatives, triazole derivatives, phenanthroline derivatives, phenylquinoxaline derivatives, benzimidazole derivatives, and pyrimidine derivatives.

[0280] Materials that can form the electron injection layer include metal oxides such as lithium oxide (Li2O), magnesium oxide (MgO), and aluminum oxide (Al2O3), as well as metal fluorides such as lithium fluoride (LiF) and sodium fluoride (NaF), but are not limited to these.

[0281] Examples of cathode materials include aluminum, magnesium-silver alloys, and aluminum-lithium alloys, but these are not the only ones that can be used.

[0282] Materials that can form an electron blocking layer include tri(phenylpyrazole)iridium, but are not limited to these.

[0283] Examples of hole-transporting polymers include poly[(9,9-dihexylfluorenyl-2,7-diyl)-copolymer-(N,N'-bis{p-butylphenyl}-1,4-diaminophenylene)], poly[(9,9-dioctylfluorenyl-2,7-diyl)-copolymer-(N,N'-bis{p-butylphenyl}-1,1'-biphenyl-4,4-diamine)], and poly[(9,9-bis{1'-penten-5'-yl}fluorenyl-2,7-diyl)-copolymer-(N,N'-bis{p-butylphenyl}-1,4-diaminophenylene)]. Poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)-benzidine], poly[(9,9-dioctylfluorenyl-2,7-diyl)-copolymer-(4,4'-(N-(p-butylphenyl))diphenylamine)], poly[(9,9-dioctylfluorenyl-2,7-diyl)-copolymer-(4,4'-(N-(4-sec-butylphenyl)diphenylamine)], poly(9-vinylcarbazole), poly(4-butyl-N,N-diphenylaniline), etc., are all end-capped with polysilsesquioxane.

[0284] Examples of luminescent polymers include polyfluorene derivatives such as poly(9,9-dialkylfluorene) (PDAF), polyphenylacetylene derivatives such as poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylacetylene) (MEH-PPV), polythiophene derivatives such as poly(3-alkylthiophene) (PAT), and polyvinylcarbazole (PVCz).

[0285] As a quantum dot material and as a semiconductor material, it can include at least one semiconductor material selected from group II-VI semiconductors, group III-V semiconductors, group I-III-VI semiconductors, group IV semiconductors, and group I-II-IV-VI semiconductors. Specific examples of the aforementioned semiconductor materials include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, and CdHgZn. nTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe; GaN, GaP, GaA s, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, A lPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaIn NAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb; SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe; Si, Ge, SiC, SiGe, AgInSe2, CuGaSe2, CuInS2, CuGaS2, CuInSe2, AgInS2, AgGaSe2, AgGaS2, C, Si, and Ge, but not limited to these.

[0286] As described above, the charge-transporting varnish of the present invention is suitable for forming functional layers disposed between the anode and the light-emitting layer, such as hole injection layers, hole transport layers, and hole injection transport layers in organic EL elements and quantum dot EL elements. In addition, it can also be used to form charge-transporting thin films in electronic components such as organic photoelectric conversion elements, organic thin-film solar cells, organic perovskite photoelectric conversion elements, organic integrated circuits, organic field-effect transistors, organic thin-film transistors, organic light-emitting transistors, organic optical detectors, organic light receivers, organic electric field extinction elements, light-emitting electrochemical cells, quantum lasers, organic laser diodes, and organic plasmon light-emitting elements.

[0287] Example

[0288] The following examples, including synthesis examples, preparation examples, embodiments, and comparative examples, illustrate the present invention in more detail, but the present invention is not limited to the embodiments described below. It should be noted that the apparatus used is as described below.

[0289] (1) 1 H-NMR: Bruker AVANCE III HD500MHz nuclear magnetic resonance spectrometer

[0290] (2) Determination of weight-average molecular weight (Mw) and number-average molecular weight (Mn): HLC-8320GPC device manufactured by Tosoh Corporation (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: polystyrene)

[0291] (3) Cleaning of substrates: manufactured by Choshu Sangyo Co., Ltd., substrate cleaning equipment (depressurized plasma method)

[0292] (4) Coating of charge-transfer varnish: Mikasa Corporation MS-A100 spin coater

[0293] (5) Contact angle measurement: Kyowa Interface Science Co., Ltd. manufactured the fully automatic contact angle meter DM-700.

[0294] (6) Fabrication of Hole-Only Devices (HODs) and Organic Electron Components: Choshu Sangyo Co., Ltd. Manufacturing, Multifunctional Evaporation System C-E2L1G1-N

[0295] (7) Measurement of brightness, etc., of single hole devices (HOD) and organic EL elements: EHC Corporation manufactures multi-channel IVL measurement devices.

[0296] [1] Synthesis of raw material compounds (monomers)

[0297] [Synthesis Example 1] Synthesis of Compound 1

[0298] Compound 1, a sodium aryl sulfonate compound represented by the following formula, was synthesized according to the method described in International Publication No. 2023 / 008176.

[0299] [Chemistry 26]

[0300]

[0301] [Synthetic Example 2] Synthesis of Compound 2

[0302] [Chemistry 27]

[0303]

[0304] Sodium hydride (55% by mass liquid paraffin dispersion, 2.97 g, 68.0 mmol, manufactured by Kanto Chemical Co., Ltd.) was added to a four-necked flask, and after replacing the atmosphere with nitrogen, dehydrated tetrahydrofuran (hereinafter referred to as "THF", 65 ml, manufactured by Kanto Chemical Co., Ltd.) was added, and the mixture was cooled to 0°C. Then, a mixed solution of 2,2,3,3,3-pentafluoro-1-propanol (8.50 g, 56.7 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.) and dehydrated THF (32 ml) was added dropwise, and the mixture was stirred at 0°C for 30 minutes. Then, a mixed solution of 2,3,4,5,6-pentafluorostyrene (10.0 g, 51.5 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.) and dehydrated THF (32 ml) was added dropwise, and the mixture was stirred at 0°C for 30 minutes. Finally, the mixture was stirred at room temperature for 4 hours.

[0305] The reaction solution was slowly added dropwise to water (310 g) under ice-cooling. The resulting mixture was separated using ethyl acetate (130 mL × 3). The resulting organic layer was dried over anhydrous sodium sulfate. The solvent was removed by drying the dried solution under reduced pressure, and the residue was purified by vacuum distillation (0.4 mmHg, 42 °C) to give compound 2 (13.6 g, 42.0 mmol) as a pale yellow oil (yield 82%). The obtained compound... 1 H-NMR spectra (measurement solvent: dimethyl sulfoxide-d6) are shown in Figure 1 .

[0306] [2] Polymer synthesis

[0307] [Example 1-1] Synthesis of Polymer A

[0308] [Chemistry 28]

[0309]

[0310] Compound 1 (2.04 g, 3.91 mmol) obtained in Synthesis Example 1, compound 2 (0.54 g, 1.68 mmol) obtained in Synthesis Example 2, 2,2'-azobis(isobutyronitrile) (hereinafter referred to as "AIBN", 46 mg, 0.28 mmol, manufactured by Kanto Chemical Co., Ltd.), and dimethyl sulfoxide (hereinafter referred to as "DMSO", 25.8 g, manufactured by Pure Chemical Co., Ltd.) were added to a three-necked flask. After degassing the solution, it was stirred at room temperature under a nitrogen atmosphere until compounds 1 and 2 were completely dissolved. Then, it was heated and stirred at 80 °C for 8 hours. The resulting solution was concentrated and added dropwise to a mixed solvent (130 g) of methanol / ethyl acetate (1 wt / 3.5 wt), and stirred at room temperature for 1 hour. The precipitated solid was then recovered by vacuum filtration and washed with a mixed solvent of methanol / ethyl acetate (1 wt / 3.5 wt). The washed solid was dried under reduced pressure to give intermediate polymer A (2.0 g).

[0311] In a flask, 2.0 g of intermediate polymer A and 30 g of a methanol / water mixture (1 wt / 1 wt) were added and stirred at room temperature. Then, 9.1 mL of cation exchange resin (Dowex Monosphere 650C, manufactured by Sigma Aldrich) was added and stirred at room temperature for 30 minutes. The cation exchange resin was removed by suction filtration, and the solvent was removed by distillation of the filtrate under reduced pressure to obtain 1.74 g of polymer A as an orange solid.

[0312] Mn=2300, Mw=6550, Mw / Mn=2.85 (GPC)

[0313] [Examples 1-2] Synthesis of Polymer B

[0314] [Chemistry 29]

[0315]

[0316] Compound 1 (2.01 g, 3.85 mmol) obtained in Synthesis Example 1, compound 2 (0.31 g, 0.96 mmol) obtained in Synthesis Example 2, AIBN (39 mg, 0.24 mmol), and DMSO (23.2 g) were added to a three-necked flask. After degassing, the solution was stirred at room temperature under a nitrogen atmosphere until compounds 1 and 2 were completely dissolved. Then, the mixture was heated and stirred at 80 °C for 8 hours. The resulting solution was concentrated and added dropwise to a mixed solvent (140 g) of methanol / ethyl acetate (1 wt / 3.5 wt), and stirred at room temperature for 1 hour. The precipitated solid was then recovered by vacuum filtration and washed with a mixed solvent of methanol / ethyl acetate (1 wt / 3.5 wt). The washed solid was dried under reduced pressure to give intermediate polymer B (1.82 g).

[0317] In a flask, 1.82 g of intermediate polymer B and 30 g of a mixed solvent of methanol / water (1 wt / 1 wt) were added and stirred at room temperature. Then, 9.1 mL of cation exchange resin (Dowex Monosphere 650C) was added and stirred at room temperature for 30 minutes. The cation exchange resin was removed by suction filtration, and the filtrate was dried under reduced pressure to distill off the solvent, yielding 1.55 g of polymer B as an orange solid.

[0318] Mn=1670, Mw=4470, Mw / Mn=2.68 (GPC)

[0319] [Comparative Example 1-1] Synthesis of Polymer C

[0320] [Chemistry 30]

[0321]

[0322] Compound 1 (1.50 g, 2.87 mmol), 2,3,4,5,6-pentafluorostyrene (0.24 g, 1.24 mmol), AIBN (34 mg, 0.21 mmol), and DMSO (17.4 g) obtained in Synthesis Example 1 were added to a three-necked flask. After degassing the solution, it was stirred at room temperature under a nitrogen atmosphere until the monomers were completely dissolved. Then, the mixture was heated and stirred at 80 °C for 9 hours. The resulting solution was concentrated and added dropwise to a mixed solvent (90 g) of methanol / ethyl acetate (1 wt / 3.5 wt), and stirred at room temperature for 1 hour. The precipitated solid was then recovered by vacuum filtration and washed with a mixed solvent of methanol / ethyl acetate (1 wt / 3.5 wt). The washed solid was dried under reduced pressure to give intermediate polymer C (1.27 g).

[0323] In a flask, 1.27 g of intermediate polymer C and 20 g of a mixed solvent of methanol / water (1 wt / 1 wt) were added and stirred at room temperature. Then, 6.4 mL of cation exchange resin (Dowex Monosphere 650C) was added and stirred at room temperature for 30 minutes. The cation exchange resin was removed by suction filtration, and the filtrate was dried under reduced pressure to remove the solvent, yielding 1.08 g of polymer C as an orange solid.

[0324] Mn=1910, Mw=4370, Mw / Mn=2.29 (GPC)

[0325] [3] Preparation of compositions for preparing charge-transfer varnishes

[0326] [Preparation Example 1-1]

[0327] An amine adduct of a polymer containing repeating units represented by formula (1a), synthesized sequentially according to the method described in U.S. Patent No. 8017241 and International Publication No. 2016 / 171935, namely a polythiophene derivative, was added to 0.5 g of 1,3-dimethyl-2-imidazolinone (manufactured by Kanto Chemical Co., Ltd., hereinafter the same) and 0.75 g of n-butylamine (manufactured by Tokyo Chemical Industry Co., Ltd.). The mixture was stirred at 80°C for 3 hours using a heating stirrer to obtain a solution in which polythiophene was dissolved.

[0328] [Chemistry 31]

[0329]

[0330] [Preparation Examples 1-2]

[0331] 50g of water-dispersed silica sol, namely ST-OS (manufactured by Nissan Chemical Co., Ltd.), and dipropylene glycol monomethyl ether (manufactured by Kanto Chemical Co., Ltd., the same below) were placed in a flask. Using an evaporator, the aqueous solvent contained in ST-OS was replaced with dipropylene glycol monomethyl ether to obtain silica sol dispersed in dipropylene glycol monomethyl ether (silica concentration 15.7% by mass).

[0332] [4] Preparation of charge transport varnish

[0333] [Example 2-1]

[0334] In a round-bottom flask, 2.37 g of 1,3-dimethyl-2-imidazolinone (hereinafter referred to as "DMI"), 3.38 g of dipropylene glycol (manufactured by Junsei Chemical Co., Ltd., the same below), 2.17 g of dipropylene glycol monomethyl ether, and 45 mg of polymer A synthesized in Example 1-1 were added, and the mixture was stirred at 50°C for 1 hour using a stirrer. Then, 0.60 g of the polythiophene solution obtained in Preparation Example 1-1 was added, and the mixture was stirred at room temperature for 30 minutes. Then, 1.44 g of silica sol dispersed in dipropylene glycol monomethyl ether obtained in Preparation Example 1-2 was added, and the mixture was stirred at room temperature for 30 minutes. The resulting solution was filtered through a 0.2 μm PP syringe filter to obtain a charge-transfer varnish.

[0335] [Example 2-2]

[0336] In a round-bottom flask, DMI (2.37 g), dipropylene glycol (3.38 g), dipropylene glycol monomethyl ether (2.17 g), and polymer B (45 mg) synthesized in Examples 1-2 were added, and the mixture was stirred at 50°C for 1 hour. Then, 0.60 g of the polythiophene solution obtained in Preparation Example 1-1 was added, and the mixture was stirred at room temperature for 30 minutes. Next, 1.44 g of silica sol dispersed in dipropylene glycol monomethyl ether obtained in Preparation Example 1-2 was added, and the mixture was stirred at room temperature for 30 minutes. The resulting solution was filtered through a 0.2 μm PP syringe filter to obtain a charge-transfer varnish.

[0337] [Examples 2-3]

[0338] DMI (3.02 g), 2,3-butanediol (4.02 g, manufactured by Kanto Chemical Co., Ltd., hereinafter the same), dipropylene glycol monomethyl ether (2.71 g), and polymer A synthesized in Example 1-1 (0.17 g) were added to a flask and stirred at 50°C for 1 hour. Then, aniline compound represented by formula (2a) synthesized according to the method described in International Publication No. 2013 / 084664 (0.08 g) was added and stirred at room temperature for 30 minutes. The resulting solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a charge-transfer varnish.

[0339] [Chemistry 32]

[0340]

[0341] [Examples 2-4]

[0342] DMI (3.02 g), 2,3-butanediol (4.02 g), dipropylene glycol monomethyl ether (2.71 g), and polymer B synthesized in Examples 1-2 (0.17 g) were added to a flask and stirred at 50°C for 1 hour. Then, aniline compound represented by formula (2a) (0.08 g) was added and stirred at room temperature for 30 minutes. The resulting solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a charge-transfer varnish.

[0343] [Comparative Example 2-1]

[0344] In a round-bottom flask, DMI (2.37 g), dipropylene glycol (3.38 g), dipropylene glycol monomethyl ether (2.17 g), and polymer C (45 mg) synthesized in Comparative Example 1-1 were added, and the mixture was stirred at 50°C for 1 hour. Then, 0.60 g of the polythiophene solution obtained in Preparation Example 1-1 was added, and the mixture was stirred at room temperature for 30 minutes. Next, 1.44 g of silica sol dispersed in dipropylene glycol monomethyl ether obtained in Preparation Example 1-2 was added, and the mixture was stirred at room temperature for 30 minutes. The resulting solution was filtered through a 0.2 μm PP syringe filter to obtain a charge-transfer varnish.

[0345] [Comparative Example 2-2]

[0346] DMI (3.02 g), 2,3-butanediol (4.02 g), dipropylene glycol monomethyl ether (2.71 g), and polymer C synthesized in Comparative Example 1-1 (0.17 g) were added to a round-bottom flask, and the mixture was stirred at 50 °C for 1 hour. Then, aniline compound represented by formula (2a) (0.08 g) was added, and the mixture was stirred at room temperature for 30 minutes. The resulting solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a charge-transfer varnish.

[0347] [5] Evaluation of water contact angle on charge transport thin films

[0348] [Example 3-1]

[0349] After applying the charge-transporting varnish obtained in Example 2-1 to an ITO substrate using a spin coater, it was fired at 120°C for 1 minute under atmospheric conditions. Next, it was fired at 230°C for 15 minutes under atmospheric conditions to form a uniform thin film with a thickness of 65 nm on the ITO substrate. It should be noted that the ITO substrate used was a 50 mm × 50 mm × 0.7 t glass substrate with indium tin oxide (ITO) patterned on it at a film thickness of 50 nm. Before use, impurities on the surface were removed using an O2 plasma cleaning device (150 W, 30 seconds).

[0350] [Examples 3-2 to 3-4, Comparative Examples 3-1 to 3-2]

[0351] Except that the charge transport varnish was changed to the charge transport varnish obtained in Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-2, a uniform thin film with a thickness of 65 nm was formed on the ITO substrate using the same method as in Example 3-1.

[0352] For the charge-transporting thin films on the ITO substrates formed in Examples 3-1 to 3-4 and Comparative Examples 3-1 to 3-2, the water contact angle on each film was measured using a contact angle meter. The amount of water droplet was set to 1.1 μL, and the contact angle value was measured 7 seconds after the droplet's contact. The results are shown in Table 1.

[0353] [Table 1]

[0354]

[0355] As shown in Table 1, comparing the results of Examples 3-1 to 3-2 with Comparative Example 3-1 and the results of Examples 3-3 to 3-4 with Comparative Example 3-2, it can be seen that the water contact angle of the film formed using a charge-transporting varnish containing polymer A or polymer B is higher than that of the film formed using a charge-transporting varnish containing polymer C. One of the main reasons is believed to be that polymers A and B contain fluorinated alkyl groups with low surface energy within their molecules, thus making them more prone to surface deviation when forming charge-transporting films compared to polymer C.

[0356] [6] Fabrication and evaluation of single hole devices (HODs)

[0357] [Example 4-1]

[0358] After applying the charge-transporting varnish obtained in Example 2-1 to an ITO substrate using a spin coater, it was dried at 120°C for 1 minute in an atmospheric atmosphere. Next, it was fired at 230°C for 15 minutes in an atmospheric atmosphere to form a uniform 65 nm thin film on the ITO substrate. It should be noted that a 25 mm × 25 mm × 0.7 t glass substrate with a patterned 150 nm thick ITO film formed on its surface was used as the ITO substrate. Before use, impurities on the surface were removed using an O2 plasma cleaning device (150 W, 30 seconds).

[0359] Secondly, for ITO substrates with thin films, an evaporation apparatus (vacuum degree 1.0 × 10⁻⁶) is used. -5 α-NPD (N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine) manufactured by Nippon Steel & Sumitomo Metal Chemicals Co., Ltd. was deposited at a vapor deposition rate of 0.2 nm / s to a film at 80 nm. Next, aluminum was deposited at a vapor deposition rate of 0.2 nm / s to a film at 80 nm to obtain HOD.

[0360] It should be noted that, to prevent performance degradation caused by the influence of oxygen and water in the air, the characteristics of the HOD are evaluated after it is sealed with a sealing substrate. The sealing is performed using the following steps: In a nitrogen atmosphere with an oxygen concentration below 2 ppm and a dew point below -76°C, the organic EL element is placed between sealing substrates, and the sealing substrates are bonded together using an adhesive (MORESCO Moisture Cut WB90US(P) manufactured by MORESCO Co., Ltd.). At this time, a water-absorbing agent (Dynic Co., Ltd., HD-071010W-40) is placed inside the sealing substrate along with the HOD. The bonded sealing substrate is then irradiated with UV light (wavelength: 365 nm, irradiation dose: 6000 mJ / cm²). 2 After that, anneal at 80°C for 1 hour to cure the adhesive.

[0361] [Examples 4-2 to 4-4, Comparative Examples 4-1 to 4-2]

[0362] Except that the charge transport varnish was changed to the charge transport varnish obtained in Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-2, respectively, the HOD was prepared using the same method as in Example 4-1.

[0363] For each component fabricated in Examples 4-1 to 4-4 and Comparative Examples 4-1 to 4-2, the current-voltage characteristics were evaluated. Specifically, for the fabricated HOD, the current density (mA / cm²) was measured when a voltage was applied at intervals of 0.25V from -5V to +5V. 2 For each component, the current density when a voltage of +5V is applied is shown in Table 2.

[0364] [Table 2]

[0365]

[0366] As shown in Table 2, comparing the results of Examples 4-1 to 4-2 with Comparative Example 4-1 and the results of Examples 4-3 to 4-4 with Comparative Example 4-2, it can be seen that the HOD using a charge-transporting varnish containing polymer A or polymer B exhibits a higher current flow rate compared to the HOD using a charge-transporting varnish containing polymer C. Based on these results, it is believed that when forming a charge-transporting thin film from each charge-transporting varnish, polymer A or polymer B, which functions as a dopant, tends to be biased towards the film surface compared to the case using polymer C. Therefore, by efficiently doping the charge-transporting material present on the film surface, the hole injection capability into the NPB film formed on the upper layer is improved.

[0367] [7] Fabrication and evaluation of organic EL elements

[0368] [Example 5-1]

[0369] After applying the charge-transporting varnish obtained in Example 2-1 to an ITO substrate using a spin coater, it was dried at 120°C for 1 minute in an atmospheric atmosphere. Next, it was fired at 230°C for 15 minutes in an atmospheric atmosphere to form a uniform 65 nm thin film on the ITO substrate.

[0370] Secondly, for ITO substrates with thin films, an evaporation apparatus (vacuum degree 1.0 × 10⁻⁶) is used. -5 At a deposition rate of 0.2 nm / s, α-NPD was deposited at a thickness of 30 nm. Next, HTEB-01 electron blocking material manufactured by Kanto Chemical Co., Ltd. was deposited at a thickness of 10 nm. Then, NS60, the host material for the light-emitting layer, and Ir(ppy)3, the dopant material for the light-emitting layer, manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., were co-deposited. For co-deposition, the deposition rate was controlled with an Ir(ppy)3 concentration of 6%, and the layers were stacked at a thickness of 40 nm. Next, thin films of Alq3, lithium fluoride, and aluminum were sequentially stacked to obtain an organic EL device. At this point, the deposition rate was 0.2 nm / s for Alq3 and aluminum, and 0.02 nm / s for lithium fluoride, with film thicknesses set to 20 nm, 0.5 nm, and 80 nm, respectively.

[0371] [Chemistry 33]

[0372]

[0373] It should be noted that, to prevent performance degradation caused by the influence of oxygen and water in the air, the characteristics of the organic EL element are evaluated after sealing it with a sealing substrate. The sealing process is as follows: In a nitrogen atmosphere with an oxygen concentration below 2 ppm and a dew point below -76°C, the organic EL element is placed between sealing substrates, and the sealing substrates are bonded together using an adhesive (MORESCO Moisture Cut WB90US(P) manufactured by MORESCO Co., Ltd.). At this time, a water-absorbing agent (Dynic Co., Ltd., HD-071010W-40) is placed inside the sealing substrate along with the organic EL element. The bonded sealing substrate is then irradiated with UV light (wavelength: 365 nm, irradiation dose: 6000 mJ / cm²). 2 After that, anneal at 80°C for 1 hour to cure the adhesive.

[0374] [Examples 5-2 to 5-4, Comparative Examples 5-1 to 5-2]

[0375] Except that the charge transport varnish was changed to the charge transport varnish obtained in Examples 2-2 to 2-4 and Comparative Examples 2-1 to 2-2, the organic EL element was fabricated using the same method as in Example 5-1.

[0376] For each element manufactured in Examples 5-1 to 5-4 and Comparative Examples 5-1 to 5-2, the brightness was measured at 10000 cd / m². 2 The driving voltage, current density, luminous efficiency, and luminance at LT80 (initial luminance 10000 cd / m²) during driving. 2 (Time required for decay to 80%). The results are shown in Table 3.

[0377] [Table 3]

[0378]

[0379] As shown in Table 3, comparing the results of Examples 5-1 to 5-2 with Comparative Example 5-1, and the results of Examples 5-3 to 5-4 with Comparative Example 5-2, it can be seen that the organic EL element using a charge-transporting varnish containing polymers A and B exhibits lower driving voltage, higher efficiency, and longer lifespan compared to the organic EL element using a charge-transporting varnish containing polymer C. Regarding this result, it is believed that, related to the results of HOD described above, the charge-transporting film obtained from a charge-transporting varnish containing polymer A or polymer B has improved hole injection into the hole transport layer formed on top, compared to the charge-transporting film obtained from a charge-transporting varnish containing polymer C, thus leading to improved characteristics of the organic EL element.

Claims

1. A fluoroaryl sulfonic acid polymer compound, characterized in that, It contains repeating units represented by the following equations (1) and (2). [Chemistry 1] In the formula, Ar F1 and Ar F2 Each independently represents a fluoroarylene group, X 1 and X 2 Each can independently represent O, S, NH, CONH or NHCO, Ar S This indicates an aryl group having at least one SO3R group on the ring, where R represents a hydrogen atom or an alkali metal atom. 1 R represents an alkyl group with 3 to 10 carbon atoms that has been substituted by at least one fluorine atom. 2 and R 3 Each can be used independently to represent a hydrogen atom or a methyl group.

2. The fluoroaryl sulfonic acid polymer compound according to claim 1, wherein, The Ar F1 and Ar F2 It is a perfluoroaryl group.

3. The fluoroaryl sulfonic acid polymer compound according to claim 2, wherein, The Ar F1 and Ar F2 It is tetrafluorophenylene.

4. The fluoroaryl sulfonic acid polymer compound according to claim 1, wherein, The Ar S An aryl group having two or more of the SO3R groups on a ring.

5. The fluoroaryl sulfonic acid polymer compound according to claim 4, wherein, The Ar S A naphthyl group having two or more of the SO3R groups on the ring.

6. The fluoroaryl sulfonic acid polymer compound according to claim 1, wherein, The X 1 and X 2 It is O.

7. A dopant material comprising the fluoroaryl sulfonic acid polymer compound according to claim 1.

8. A charge-transporting varnish comprising a charge-transporting substance, a dopant substance according to claim 7, and a solvent.

9. The charge-transporting varnish according to claim 8, wherein, The charge-transporting substance is an arylamine derivative or a thiophene derivative.

10. A charge-transporting thin film obtained from the charge-transporting varnish according to claim 8 or 9.

11. An electronic component comprising the charge-transporting thin film according to claim 10.

12. The electronic component according to claim 11, wherein, The charge transport thin film is a hole injection layer or a hole transport layer.

13. The electronic component according to claim 11, wherein, The electronic component is an organic electroluminescent element or a quantum dot electroluminescent element.

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