Composition consisting of polythiophene and organic solvent, and use thereof

Abstract

To provide a polythiophene and organic solvent composition that can form a micron-level coating having excellent conductivity and no cracks.SOLUTION: Provided is a composition, which is a composition comprising a polythiophene that contains a structural unit represented by formula (1), a solvent (A) having a normal boiling point of 30 to 150°C, and a solvent (B) having a normal boiling point of 150 to 300°C, and in which, characterized, the contained amount of polythiophene is 0.01 to 25 mass%, the contained amount of the solvent (A) having a normal boiling point of 30 to 150°C is 50 to 99 mass%, and the contained amount of the solvent (B) having a normal boiling point of 150 to 300°C is 0.5 to 30 mass%.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a composition comprising a polythiophene dispersible or soluble in an organic solvent and an organic solvent, and uses thereof. [Background technology]

[0002] Polythiophene-based self-doped conductive polymers have high conductivity and are therefore being studied in a wide range of fields, such as solid electrolytic capacitors, antistatic agents, hole injection agents for solar cells, transparent electrodes, etc. Examples of using an organic solvent solution as a solvent for a polythiophene-based self-doped conductive polymer solution in these applications have been reported (e.g., Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-210356 A Summary of the Invention [Problem to be solved by the invention]

[0004] When an attempt was made to form a film having a thickness in the order of microns using an organic solvent solution of a conductive polymer specifically disclosed in Patent Document 1, it was found that cracks and mottled patterns were likely to occur, making it difficult to form a film with a good yield. [Means for solving the problem]

[0005] As a result of extensive research, the present inventors have discovered that by using the composition shown below, micron-sized films which are less likely to develop cracks or mottled patterns can be produced with good yield, and have thus completed the present invention.

[0006] That is, the present invention resides in the following [1] to [8]. [1] At least the following general formulas (1) and (2)

[0007] [ka]

[0008] [ka]

[0009] In the above general formulas (1) and (2), R 1 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. 1 is [NH(R 2 )(R 3 ) 2 ] + Or, an organic ammonium ion represented by [N(R 2 )(R 3 ) 3 ] + R represents a quaternary ammonium cation represented by the formula: 2 R represents an alkyl group having 7 to 20 carbon atoms or an alkyl group having a substituent and a total of 7 to 20 carbon atoms. 3 each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an alkyl group having a substituent and a total of 1 to 20 carbon atoms. m represents an integer of 1 to 6.} a solvent (A) having a standard boiling point of 30 to 150°C, and a solvent (B) having a standard boiling point of 150 to 300°C, wherein the content of the polythiophene is 0.01 to 25% by weight, the content of the solvent (A) having a standard boiling point of 30 to 150°C is 50 to 99% by weight, and the content of the solvent (B) having a standard boiling point of 150 to 300°C is 0.5 to 30% by weight. [2] The composition described in [1], wherein m is 2 or 3. [3] R 1 is a methyl group. [4] The composition according to [1], wherein the solvent (A) having a normal boiling point of 30 to 150°C is one single solvent or a mixed solvent of two or more selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-butanol, tert-butyl alcohol, 1-methoxy-2-propanol, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, chlorobenzene, and ethyl acetate. [5] The composition according to [1], wherein the solvent (B) having a normal boiling point of 150 to 300°C is one single solvent or a mixed solvent of two or more selected from the group consisting of 1,3-butanediol, 1,4-butanediol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monopropyl ether, ethylene glycol monohexyl ether, dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, γ-butyrolactone, cyclohexanone, dimethylsulfoxide, and glycerin. [6] A method for producing a conductive polymer film, comprising: applying a conductive polymer composition containing the composition according to [1] onto a support; heating the applied composition to 40°C or higher to mainly evaporate the solvent (A); and then increasing the heating temperature to evaporate the solvent (B). Effect of the Invention

[0010] According to the present invention, a highly conductive coating film having micron-level thickness and free of cracks and spots can be produced with good yield.

[0011] When the polythiophene is heated to form a film, solvents having different boiling points are evaporated in at least two stepwise stages, which acts to suppress segregation and rapid solidification of the polythiophene, and it is presumed that the above-mentioned effects are realized based on this action. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention will be described in detail below.

[0013] The present invention is a composition comprising a polythiophene containing at least structural units represented by the above general formulas (1) and (2), a solvent (A) having a standard boiling point of 30 to 150°C, and a solvent (B) having a standard boiling point of 150 to 300°C, wherein the content of the polythiophene is 0.01 to 25% by weight, the content of the solvent (A) having a standard boiling point of 30 to 150°C is 50 to 99% by weight, and the content of the solvent (B) having a standard boiling point of 150 to 300°C is 0.5 to 30% by weight.

[0014] The polythiophene of the present invention is a polythiophene containing structural units represented by the above general formulas (1) and (2).

[0015] The structural unit represented by the general formula (2) represents a doped state of the structural unit represented by the general formula (1), and the doped state is realized by the sulfo group or sulfonate group in the structural unit represented by the general formula (1) acting as a p-type dopant.

[0016] In the above general formula (1) or (2), R 1 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom.

[0017] The alkyl group having 1 to 6 carbon atoms (an alkyl group having 3 to 6 carbon atoms may be linear or branched) is not particularly limited, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an n-hexyl group, a 2-ethylbutyl group, and a cyclohexyl group.

[0018] The halogen atom includes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like.

[0019] Among these, the substituent R 1 From the viewpoint of film-forming properties, it is preferable that the group is a hydrogen atom, a methyl group, an ethyl group, a fluorine atom, a chlorine atom, or a bromine atom, more preferably a hydrogen atom, a methyl group, or a fluorine atom, and most preferably a methyl group.

[0020] In the general formula (1), M 1 is [NH(R 2 )(R 3 ) 2 ] + Or, an organic ammonium ion represented by [N(R 2 )(R 3 ) 3 ] + It represents a quaternary ammonium cation represented by the formula:

[0021] The above [NH(R 2 )(R 3 ) 2 ] + The organic ammonium ion represented by [N(R 2 )(R 3 ) 2 ] is an organic amine compound represented by the formula + The cationic species (conjugate acid) is shown. 2 )(R 3 ) 2 In the case of organic amine compounds represented by the formula [NH(R 2 )(R 3 ) 2 ] + It forms an organic ammonium ion (conjugate acid) represented by the formula:

[0022] The above-mentioned substituent R 2 represents an alkyl group having 7 to 20 carbon atoms, or an alkyl group having a substituent and a total of 7 to 20 carbon atoms.

[0023] The alkyl group having 7 to 20 carbon atoms (which may be linear or branched) is not particularly limited, but examples thereof include an n-heptyl group, a methylhexyl group, an n-octyl group, a methylheptyl group, an ethylhexyl group, an n-nonyl group, an n-decyl group, an ethyloctyl group, a butylhexyl group, an n-undecyl group, an n-dodecyl group, an n-hexadecyl group, an n-heptadecyl group, an octylnonyl group, an n-octadecyl group, an n-nonadecyl group, an n-icosyl group, and an octyldodecane group.

[0024] Examples of the substituted alkyl group having a total of 7 to 20 carbon atoms (which may be linear or branched) include an alkyl group having a total of 7 to 20 carbon atoms (which may be linear or branched) which has a halogen atom, an amino group, or a hydroxy group, and specific examples include an 8-hydroxyoctyl group, a 9-aminononyl group, and the like.

[0025] Among these, the substituent R 2 From the viewpoint of availability, an n-heptyl group, a methylhexyl group, an n-octyl group, a methylheptyl group, a 2-ethylhexyl group, an n-nonyl group, an n-decyl group, or an n-dodecyl group is preferable.

[0026] The above-mentioned substituent R 3 each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms (an alkyl group having 3 to 20 carbon atoms may be linear or branched), or an alkyl group having a total of 1 to 20 carbon atoms and having a substituent (an alkyl group having 3 to 20 carbon atoms may be linear or branched).

[0027] The alkyl group having 1 to 20 carbon atoms (an alkyl group having 3 to 20 carbon atoms may be linear or branched) is not particularly limited, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an n- Examples of such alkyl groups include hexyl, 2-ethylbutyl, cyclohexyl, n-heptyl, methylhexyl, n-octyl, methylheptyl, ethylhexyl, n-nonyl, n-decyl, ethyloctyl, butylhexyl, n-undecyl, n-dodecyl, n-hexadecyl, n-heptadecyl, octylnonyl, n-octadecyl, n-nonadecyl, n-icosyl, and octyldodecyl groups.

[0028] Examples of the substituted alkyl group having 1 to 20 carbon atoms (note that, in the case of an alkyl group having 3 to 20 carbon atoms, it may be linear or branched) include an alkyl group having a total of 1 to 20 carbon atoms and having a halogen atom, an amino group, or a hydroxy group (note that, in the case of an alkyl group having 3 to 20 carbon atoms, it may be linear or branched), and specific examples thereof include a trifluoromethyl group, a 2-hydroxyethyl group, an 8-hydroxyoctyl group, and a 9-aminononyl group.

[0029] Among these, the substituent R 3 are each independently preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, a 2-ethylbutyl group, an n-heptyl group, a methylhexyl group, an n-octyl group, a methylheptyl group, a 2-ethylhexyl group, an n-nonyl group, an n-decyl group, or an n-dodecyl group.

[0030] The above [N(R 2 )(R 3 ) 2The organic amine compound represented by the formula] is not particularly limited, and examples thereof include n-heptylamine, di-n-heptylamine, tri-n-heptylamine, n-octylamine, di-n-octylamine, tri-n-octylamine, N-methyl-di-n-octylamine, n-nonylamine, di-n-nonylamine, tri-n-nonylamine, n-decylamine, di-n-decylamine, tri-n-decylamine, n-dodecylamine, di-n-dodecylamine, tri-n-dodecylamine, n-hexadecylamine, di-n-hexadecylamine, tri-n-hexadecylamine, n-octadecylamine, di-n-octadecylamine, tri-n-octadecylamine, n-icosylamine, di-n-icosylamine, tri-n-icosylamine, N,N-dimethyl-n -heptylamine, N,N-dimethyl-n-octylamine, N,N-dimethyl-n-nonylamine, N,N-dimethyl-n-decylamine, N,N-dimethyl-n-dodecylamine, N,N-dimethyl-n-hexadecylamine, N,N-dimethyl-n-octadecylamine, N,N-dimethyl-n-icosylamine, N,N-diethyl-n-heptylamine, N,N-diethyl-n-octylamine, N,N-diethyl-n-nonylamine, N,N-diethyl-n-decylamine, N,N-diethyl-n-dodecylamine, N,N-diethyl-n-hexadecylamine, N,N-diethyl-n-octadecylamine, N,N-diethyl-n-icosylamine, N-methylhexylamine, 2-octylamine, N,N-dimethyl-2-ethylhexan-1-amine, N,N-Diisopropyl-2-ethylhexylamine, 6-methyl-1-heptylamine, di(6-methyl-1-heptyl)amine, tris(6-methyl-1-heptyl)amine, 2-ethylhexylamine, di(2-ethylhexyl)amine, tris(2-ethylhexyl)amine, methyloctylamine, methylnonylamine, methyldodecylamine, methylhexadecylamine, methyloctadecylamine, ethylheptylamine, ethyloctylamine, ethylnonylamine, ethyldodecylamine, ethylhexadecylamine, ethyloctadecylamine Examples of the amino groups include amine, 7-hydroxyheptylamine, 8-hydroxyoctylamine, 9-hydroxynonylamine, 10-hydroxydecylamine, 12-hydroxydodecylamine, 16-hydroxyhexadecylamine, 18-hydroxyoctadecylamine, 20-hydroxyicosylamine, 7-aminoheptylamine, 8-aminooctylamine, 9-aminononylamine, 10-aminodecylamine, 12-aminododecylamine, 16-aminohexadecylamine, 18-aminooctadecylamine, and 20-aminoicosylamine.

[0031] The above [NH(R 2 )(R 3 ) 2 ] +The organic ammonium ion represented by the formula (I) is not particularly limited, and examples thereof include n-heptylammonium, di-n-heptylammonium, tri-n-heptylammonium, n-octylammonium, di-n-octylammonium, tri-n-octylammonium, N-methyl-di-n-octylammonium, n-nonylammonium, di-n-nonylammonium, tri-n-nonylammonium, n-decylammonium, di-n-decylammonium, tri-n-decylammonium, n-dodecylammonium, di-n-dodecylammonium, tri-n-dodecylammonium, n-hexadecylammonium, di-n-hexadecylammonium, tri-n-hexadecylammonium, n-octadecylammonium, di-n-octadecylammonium, tri-n-octadecylammonium, n-icosylammonium, di-n-icosylammonium, tri-n-icosylammonium, N,N-Dimethyl-n-heptylammonium, N,N-Dimethyl-n-octylammonium, N,N-Dimethyl-n-nonylammonium, N,N-Dimethyl-n-decylammonium, N,N-Dimethyl-n-dodecylammonium, N,N-Dimethyl-n-hexadecylammonium, N,N-Dimethyl-n-octadecylammonium, N,N-Dimethyl-n-icosylammonium, N,N-Diethyl-n-heptylammonium, N,N-Diethyl N,N-diethyl-n-octylammonium, N,N-diethyl-n-nonylammonium, N,N-diethyl-n-decylammonium, N,N-diethyl-n-dodecylammonium, N,N-diethyl-n-hexadecylammonium, N,N-diethyl-n-octadecylammonium, N,N-diethyl-n-icosylammonium, N-methylhexylammonium, 2-octylammonium, N,N-dimethyl-2-ethylhexane-1-ammonium, N,N-Diisopropyl-2-ethylhexane-1-ammonium, 6-methyl-1-heptylammonium, di(6-methyl-1-heptyl)ammonium, tris(6-methyl-1-heptyl)ammonium, 2-ethylhexylammonium, di(2-ethylhexyl)ammonium, tris(2-ethylhexyl)ammonium, methyloctylammonium, methylnonylammonium, methyldodecylammonium, methylhexadecylammonium, methyloctadecylammonium, ethylheptylammonium, ethyloctylammonium, ethylnonylammonium, ethyldodecylammonium, ethylhexadecylammonium, ethyloctadecylammonium Examples of the ammonium salt include ammonium salts such as ammonium salts of 7-hydroxyheptylammonium, 8-hydroxyoctylammonium, 9-hydroxynonylammonium, 10-hydroxydecylammonium, 12-hydroxydodecylammonium, 16-hydroxyhexadecylammonium, 18-hydroxyoctadecylammonium, 20-hydroxyicosylammonium, 7-aminoheptylammonium, 8-aminooctylammonium, 9-aminononylammonium, 10-aminodecylammonium, 12-aminododecylammonium, 16-aminohexadecylammonium, 18-aminooctadecylammonium, and 20-aminoicosylammonium.

[0032] The above [N(R 2 )(R 3 ) 3 ] + Examples of the quaternary ammonium cation represented by the formula (I) include, but are not limited to, a tetraheptylammonium cation, a tetraoctylammonium cation, a tetranonylammonium cation, a tetradecylammonium cation, a tetradodecylammonium cation, a tetrahexadecylammonium cation, a tetraoctadecylammonium cation, a tetraicosylammonium cation, and a tetraethylhexylammonium cation.

[0033] The above [N(R 2 )(R 3 )3 ] + For the quaternary ammonium cation represented by [N(R 2 )(R 3 ) 3 ] + M 3 The compound represented by the formula (1) is reacted with a polythiophene having structural units represented by the formula (1) and (2) above.

[0034] The above M 3 represents an anion, and examples thereof include, but are not limited to, a hydroxy ion, a chloride ion, a bromide ion, an iodide ion, an acetate ion, a sulfonate ion, a methylsulfonate ion, a benzenesulfonate ion, and a toluenesulfonate ion.

[0035] The above [N(R 2 )(R 3 ) 3 ] + M 3 The quaternary ammonium cationic compound represented by the formula (I) is not particularly limited, but examples thereof include tetramethylammonium chloride, tetraethylammonium chloride, tetranormalpropylammonium chloride, tetranormalbutylammonium chloride, tetranormalhexylammonium chloride, tetramethylammonium bromide, tetraethylammonium bromide, tetranormalpropylammonium bromide, tetranormalbutylammonium bromide, tetranormalhexylammonium bromide, tetramethylammonium iodide, tetraethylammonium iodide, tetranormalpropylammonium iodide, tetranormalbutylammonium iodide, tetranormalhexylammonium iodide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetranormalpropylammonium hydroxide, tetranormalbutylammonium hydroxide, or tetranormalhexylammonium hydroxide.

[0036] In the above general formula (1) or (2), m represents an integer of 1 to 6, preferably an integer of 1 to 4, and more preferably 2 to 3.

[0037] The polymer serving as the raw material for the polythiophene of the present invention is a polythiophene having at least structural units represented by the following general formulas (3) and (4), which is prepared by reacting the above-mentioned [N(R 2 )(R 3 ) 2 ], or an organic amine compound represented by [N(R 2 )(R 3 ) 3 ] + M 3 The compound can be produced by reacting the compound with a quaternary ammonium cation compound represented by the formula: embedded image After the reaction, it is preferable to combine, as necessary, operations such as solvent washing, reprecipitation, centrifugal sedimentation, ultrafiltration, dialysis, and ion exchange resin treatment.

[0038] [ka]

[0039] [ka]

[0040] [In the above general formulas (3) and (4), R 1 represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. 2 represents a hydrogen ion or an alkali metal ion, and m represents an integer of 1 to 6. The alkyl group having 1 to 6 carbon atoms (an alkyl group having 3 to 6 carbon atoms may be linear or branched) is not particularly limited, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an n-hexyl group, a 2-ethylbutyl group, and a cyclohexyl group.

[0041] The alkali metal ion is preferably, for example, a Li ion, a Na ion, or a K ion.

[0042] The polythiophene represented by the above general formula (3) or (4) is not particularly limited, but specifically includes 4-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-butanesulfonic acid polymer, 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-propanesulfonic acid polymer, 4-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-butanesulfonic acid sodium salt, polymer, sodium 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-propanesulfonate polymer, sodium 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-ethyl-1-propanesulfonate polymer, sodium 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-propyl-1-propanesulfonate polymer, sodium 3-[(2,3-dihydrothieno[3,4-b]-[1 ,4]dioxin-2-yl)methoxy]-1-butyl-1-propanesulfonic acid sodium polymer, 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-pentyl-1-propanesulfonic acid sodium polymer, 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-hexyl-1-propanesulfonic acid sodium polymer, 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-isopropyl-1-propanesulfonic acid sodium polymer -Sodium propanesulfonate polymer, sodium 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-isobutyl-1-propanesulfonate polymer, sodium 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-isopentyl-1-propanesulfonate polymer, sodium 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-fluoro-1-propanesulfonate polymer, sodium 4-[(2,3-Dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-butanesulfonic acid potassium polymer, 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-propanesulfonic acid potassium polymer, 4-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-butanesulfonic acid ammonium polymer, 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-butanesulfonic acid ammonium polymer Examples of the thieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-propanesulfonic acid ammonium polymer, 4-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-butanesulfonic acid triethylammonium polymer, and 3-[(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl)methoxy]-1-methyl-1-propanesulfonic acid triethylammonium polymer, and the like.

[0043] The solvent (A) having a standard boiling point of 30 to 150°C is not particularly limited, and examples thereof include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-butanol, tert-butyl alcohol, benzene, toluene, xylene, acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone, methyl cellosolve, ethyl cellosolve, 1,4-dioxane, methyl acetate, ethyl acetate, butyl acetate, methyl lactate, 1-methoxy-2-propanol, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, chloroform, dichloromethane, 1,2-dichloroethane, chlorobenzene, tetrahydrofuran, and water.

[0044] These solvents may be used alone or in combination of two or more kinds.

[0045] Regarding the solvent (A) having a normal boiling point of 30 to 150°C, in terms of excellent film-forming properties, it is preferable that the solvent is one single solvent or two or more mixed solvents selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-butanol, tert-butyl alcohol, 1-methoxy-2-propanol, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, chlorobenzene, and ethyl acetate, and it is more preferable that the solvent is one single solvent or two or more mixed solvents selected from the group consisting of methanol, ethanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-butanol, 1-methoxy-2-propanol, methyl ethyl ketone, methyl isobutyl ketone, and ethyl acetate.

[0046] The solvent (B) having a standard boiling point of 150 to 300°C is not particularly limited, and examples thereof include 1,3-butanediol, 1,4-butanediol, 2-ethylhexanol, benzyl alcohol, diisobutyl ketone, diacetone alcohol, cyclohexanone, butyl cellosolve, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, methyl carbitol, ethyl carbitol, butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monohexyl ether, N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, dimethylimidazolidinone, hexamethylphosphoric triamide, dimethyl sulfoxide, sulfolane, γ-butyrolactone, and glycerin.

[0047] These solvents may be used alone or in combination of two or more kinds.

[0048] Regarding the solvent (B) having a standard boiling point of 150 to 300° C., in terms of excellent film-forming properties, 1,3-butanediol, 1,4-butanediol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monopropyl ether, ethylene glycol monohexyl ether, dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, γ-butyrolactone, cyclohexanone, The solvent is preferably one type of single solvent or a mixed solvent of two or more types selected from the group consisting of dimethyl sulfoxide and glycerin, and more preferably one type of single solvent or a mixed solvent of two or more types selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monohexyl ether, dimethylformamide, N-methyl-2-pyrrolidone, 2-pyrrolidone, dimethyl sulfoxide, and glycerin.

[0049] The composition of the present invention is The content of the polythiophene is 0.01 to 25% by weight, the content of the solvent (A) having a standard boiling point of 30 to 150° C. is 50 to 99% by weight, and the content of the solvent (B) having a standard boiling point of 150 to 300° C. is 0.5 to 30% by weight. The present invention is characterized in that the content of the polythiophene is 0.01 to 25% by weight, the content of the solvent (A) having a standard boiling point of 30 to 150° C. is 50 to 99% by weight, and the content of the solvent (B) having a standard boiling point of 150 to 300° C. is 0.5 to 30% by weight. It is preferable that the content of the polythiophene is 0.01 to 15% by weight, the content of the solvent (A) having a standard boiling point of 30 to 150° C. is 60 to 99% by weight, and the content of the solvent (B) having a standard boiling point of 150 to 300° C. is 0.5 to 25% by weight, More preferably, the content of the polythiophene is 0.01 to 10% by weight, the content of the solvent (A) having a standard boiling point of 30 to 150° C. is 70 to 99% by weight, and the content of the solvent (B) having a standard boiling point of 150 to 300° C. is 0.5 to 20% by weight. It is more preferable that the content of the polythiophene is 0.01 to 5% by weight, the content of the solvent (A) having a normal boiling point of 30 to 150°C is 80 to 99% by weight, and the content of the solvent (B) having a normal boiling point of 150 to 300°C is 0.5 to 15% by weight.

[0050] The composition of the present invention can be produced by mixing the polythiophene, the solvent (A) having a normal boiling point of 30 to 150°C, and the solvent (B) having a normal boiling point of 150 to 300°C.

[0051] When mixing the composition of the present invention, in addition to general mixing and dissolving operations using a stirrer tip, stirring blades, etc., ultrasonic irradiation or homogenization treatment (for example, using a mechanical homogenizer, ultrasonic homogenizer, high-pressure homogenizer, etc.) may be performed.

[0052] The mixing can be carried out at an appropriate temperature control, and is not particularly limited. For example, the mixing can be carried out at a temperature in the range of 10 to 80°C, preferably 15 to 60°C, and more preferably 20 to 50°C.

[0053] The mixing is preferably carried out after oxygen degassing. The method for oxygen degassing is not particularly limited, but examples thereof include reduced pressure treatment and nitrogen bubbling.

[0054] The mixing time is not particularly limited, but is preferably in the range of 1 minute to 12 hours, and more preferably in the range of 1 minute to 6 hours.

[0055] The composition of the present invention can be applied to a support, then heated to 40° C. or higher to mainly evaporate the solvent (A), and then the heating temperature is increased to mainly evaporate the solvent (B), thereby producing a conductive polymer film with a good film thickness at the micron level.

[0056] The support is not particularly limited as long as the composition of the present invention can be applied thereto, and examples thereof include polymeric substrates and inorganic substrates. More specifically, examples thereof include thermoplastic resins, nonwoven fabrics, and paper. Examples of thermoplastic resins include polyethylene, polypropylene, polyethylene terephthalate, polyacrylate, and polycarbonate. Examples of nonwoven fabrics include natural fibers and synthetic fibers. Examples of paper include those mainly composed of general cellulose. Examples of other inorganic substrates are not particularly limited, and examples thereof include glass, glass fibers, ceramics, aluminum oxide, and tantalum oxide.

[0057] The method for applying the composition of the present invention is not particularly limited, and examples thereof include casting, dipping, bar coating, dispenser, roll coating, gravure coating, flexographic printing, spray coating, spin coating, and inkjet methods. The spin coating method is preferred.

[0058] The temperature at which the solvent (A) is mainly evaporated is preferably in the range of 40°C to 150°C, more preferably in the range of 80°C to 140°C, and still more preferably in the range of 100°C to 130°C, in terms of producing a conductive polymer membrane of higher quality.

[0059] The heat treatment time for mainly evaporating the solvent (A) is not particularly limited, but is preferably in the range of 5 to 120 minutes, more preferably in the range of 15 to 90 minutes, in terms of producing a conductive polymer membrane of higher quality.

[0060] Furthermore, the temperature at which the solvent (B) is mainly evaporated is preferably in the range of 120°C to 300°C, more preferably in the range of 140°C to 260°C, and still more preferably in the range of 160°C to 240°C, in terms of producing a conductive polymer film of higher quality.

[0061] The heat treatment time for mainly evaporating the solvent (B) is not particularly limited, but is preferably in the range of 5 to 240 minutes, more preferably in the range of 15 to 180 minutes, in terms of producing a conductive polymer film of higher quality.

[0062] The drying atmosphere may be any of air, inert gas, vacuum, and reduced pressure, but from the viewpoint of preventing deterioration of the polymer film, an inert gas atmosphere such as nitrogen or argon is preferred.

[0063] When forming a film from the composition of the present invention, additives may be added to the composition as appropriate. The additives are not particularly limited, but may include, for example, polyhydric alcohol compounds, surfactants, binder resins, crosslinking agents, lubricants, etc.

[0064] The polyhydric alcohol compound is not particularly limited, but may be erythritol, sorbitol, mannitol, xylitol, arabitol, etc. Among these, sorbitol is preferred.

[0065] The surfactant is not particularly limited, but examples thereof include polymeric nonionic surfactants, amphoteric surfactants, fluorine-based surfactants, silicone-based surfactants, and acetylene glycol-based surfactants.

[0066] The polymeric nonionic surfactant is not particularly limited, but may be polyvinylpyrrolidone or a copolymer of polyvinylpyrrolidone. The average molecular weight of polyvinylpyrrolidone is preferably 1,000 to 2,000,000, more preferably 10,000 to 1,500,000. The copolymer of polyvinylpyrrolidone is not particularly limited, but may be one having both a hydrophilic part and a hydrophobic part in the polymer chain, such as a copolymer in which polyvinylpyrrolidone is grafted to polyvinyl alcohol, a [vinylpyrrolidone-vinyl acetate] block copolymer, a [vinylpyrrolidone-methyl methacrylate] copolymer, a [vinylpyrrolidone-normal butyl methacrylate] copolymer, or a [vinylpyrrolidone-acrylamide] copolymer.

[0067] The amphoteric surfactant is not particularly limited, but examples thereof include betaine-type amphoteric surfactants, such as alkyl dimethyl betaine, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine.

[0068] The fluorosurfactant is preferably one having a perfluoroalkyl group, and although there is no particular limitation, examples thereof include perfluoroalkanes, perfluoroalkyl carboxylic acids, perfluoroalkyl sulfonic acids, and perfluoroalkyl ethylene oxide adducts.

[0069] The silicone-based surfactant is not particularly limited, but examples thereof include polyether-modified polydimethylsiloxane, polyetherester-modified polydimethylsiloxane, hydroxyl group-containing polyether-modified polydimethylsiloxane, acrylic group-containing polyether-modified polydimethylsiloxane, acrylic group-containing polyester-modified polydimethylsiloxane, perfluoropolyether-modified polydimethylsiloxane, perfluoropolyester-modified polydimethylsiloxane, and silicone-modified acrylic compounds.

[0070] The binder resin is not particularly limited, but examples thereof include acrylic resin, polyurethane resin, polymethyl methacrylate resin, styrene butadiene resin, vinyl acetate resin, polyamide resin, phenol resin, epoxy resin, melamine resin, thermosetting polyimide, nitrocellulose or other cellulose resin, and polyvinyl alcohol resin.

[0071] The crosslinking agent is not particularly limited, but examples thereof include aminopropyltrimethoxysilane, epoxypropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, propyltriethoxysilane, aminopropyltriethoxysilane, epoxypropyltriethoxysilane, and 3-glycidyloxypropyltriethoxysilane. Among these, 3-glycidyloxypropyltrimethoxysilane and 3-glycidyloxypropyltriethoxysilane are preferred in terms of excellent film-forming properties.

[0072] The lubricant refers to a lubricant (lubricant for plastics, lubricant for resins) used as a general resin additive, and examples of the lubricant include those that have the effect of reducing friction between the plastic and the molding machine and between plastic particles in the molding process of plastics. The lubricant includes those that act as external lubricants and those that are effective in internal lubrication, and in the present invention, either one may be used alone or both may be used. Examples of the lubricant include, but are not limited to, hydrocarbon-based lubricants (paraffin wax, synthetic polyethylene, liquid paraffin), fatty acid-based lubricants (stearic acid, behenic acid, 12-hydroxystearic acid), higher alcohol-based lubricants (stearyl alcohol), fatty acid amide-based lubricants (stearic acid amide, oleic acid amide, erucic acid amide, methylene bisstearic acid amide, ethylene bisstearic acid amide), ester-based lubricants (glycerin monostearate, glycerin monooleate, butyl stearate), silicone oil, and silicone powder.

[0073] The composition of the present invention is expected to be used in applications such as capacitors, touch sensors, antistatic agents, organic thin-film solar cells, organic electroluminescence (EL), electrodes, etc. The composition containing the polythiophene of the present invention may contain additives such as known surfactants and / or binders depending on the application. [Brief description of the drawings]

[0074] [Figure 1] 3 is a photograph showing the state of a polythiophene film formed in Example 1 using a composition consisting of polythiophene, a solvent (A) having a normal boiling point of 30 to 150° C., and a solvent (B) having a normal boiling point of 150 to 300° C. [Diagram 2] 3 is a photograph showing the state of a polythiophene film formed in Reference Example 1 using a composition comprising polythiophene and a solvent (A) having a boiling point of 30 to 150° C.; EXAMPLES

[0075] The following examples are given, but the present invention should not be construed as being limited to these examples. Measurement methods used in the examples are listed below. [Film forming method] 2 ml of the composition shown in the following Examples was cast onto a 50 mm square alkali-free glass plate, and heated at 120° C. for 30 minutes and at 200° C. for 60 minutes to obtain a film. Regarding the film-forming property, a state in which no cracks were observed by visual inspection was deemed to be "good film-forming property." [Film thickness measurement] Equipment: DEKTAK XT manufactured by BRUKER.

[0076] Example 1 Polythiophenes obtained based on JP 2019-210356 A [polythiophenes consisting of structural units of the above formulas (1) and (2) (wherein R 1 = methyl group, M 1= dioctylammonium, m = 2. Hereinafter abbreviated as P1), 0.1 g of a solid was added to 9.9 g of a mixture of 90% by weight of 1-butanol and 10% by weight of ethylene glycol, and stirred at 20°C for 30 minutes to obtain a composition of the present invention. After that, a film was formed under the conditions of the above-mentioned film formation method, and a conductive polymer film with good film formability was obtained.

[0077] Examples 2 to 17 A composition of the present invention was obtained by mixing and stirring under the same conditions as in Example 1, except that 9.9 g of a mixture having the composition shown in Table 1 was used instead of 9.9 g of a mixture consisting of 90 wt % 1-butanol and 10 wt % ethylene glycol in Example 1, and a film formation test was performed. In each case, a conductive polymer film with good film formability was obtained.

[0078] Example 18 In Example 1, instead of using 0.1 g of the solid polythiophene P1, polythiophene P2 [a polythiophene consisting of the structural units of the above formulas (1) and (2) (wherein R 1 = methyl group, M 1 = trioctylammonium, m = 2.) was used. When a film was formed by the above-mentioned film formation method, a polythiophene film with good film formability was obtained.

[0079] Examples 19 to 34 In Example 18, 9.9 g of a mixture having the composition shown in Table 2 was used instead of 9.9 g of a mixture consisting of 90% by weight of 1-butanol and 10% by weight of ethylene glycol, but mixing and stirring were performed under the same conditions as in Example 19 to obtain a composition of the present invention, and a film formation test was performed. In each case, a conductive polymer film with good film formability was obtained.

[0080] Example 35 In Example 1, instead of using 0.1 g of the solid polythiophene P1, polythiophene P3 [a polythiophene consisting of the structural units of the above formulas (1) and (2) (wherein R 1 = methyl group, M 1= di(2-ethylhexyl)ammonium, m = 2.) was used. When a film was formed by the above-mentioned film formation method, a conductive polymer film with good film formability was obtained.

[0081] Examples 36 to 51 A composition of the present invention was obtained by mixing and stirring under the same conditions as in Example 35, except that 9.9 g of a mixture having the composition shown in Table 3 was used instead of 9.9 g of a mixture consisting of 90 wt % 1-butanol and 10 wt % ethylene glycol in Example 35, and a film formation test was performed. In each case, a conductive polymer film with good film formability was obtained.

[0082] Example 52 In Example 1, instead of using 0.1 g of the solid polythiophene P1, polythiophene P4 [a polythiophene consisting of the structural units of the above formulas (1) and (2) (wherein R 1 = methyl group, M 1 = decylammonium, m = 2.) was used. When a film was formed by the above-mentioned film formation method, a conductive polymer film with good film formability was obtained.

[0083] Examples 53 to 68 A composition of the present invention was obtained by mixing and stirring under the same conditions as in Example 52, and a film formation test was carried out, except that 9.9 g of a mixed solution having the composition shown in Table 4 was used instead of 9.9 g of a mixed solution consisting of 90 wt % of 1-butanol and 10 wt % of ethylene glycol in Example 52. In each case, a conductive polymer film with good film formability was obtained.

[0084] Comparative Example 1 Polythiophene P1 [a polythiophene consisting of structural units of the above formulas (1) and (2) (wherein R 1 = methyl group, M 1= dioctylammonium, m = 2.) was added to 9.9 g of 1-butanol and stirred at 20°C for 30 minutes to obtain a composition. After that, a film was formed by the above-mentioned film formation method, and a conductive polymer film with cracks was obtained.

[0085] [Table 1]

[0086] [Table 2]

[0087] [Table 3]

[0088] [Table 4] [Industrial Applicability]

[0089] The composition of the present invention, which is composed of the above polythiophene, a solvent (A) having a boiling point of 30 to 150° C., and a solvent (B) having a boiling point of 150 to 300° C., has good film-forming properties and can be used as an antistatic agent, a solid electrolyte for a capacitor, an antistatic film, a solid electrolyte for a solid electrolytic capacitor, and a separator for a wound aluminum electrolytic capacitor. In addition, the composition can be expected to be applied to organic thin-film solar cells, organic electroluminescence, electrochromic elements, transparent electrodes, transparent conductive films, thermoelectric conversion materials, chemical sensors, actuators, electromagnetic shielding materials, conductive paints, conductive inks, etc.

Claims

1. At least the following general formulas (1) and (2) 【Chemistry 1】 【Chemistry 2】 In the above general formulas (1) and (2), R １ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. １ is [NH(R ２ ) (R ３ ) ２ ] ＋ or an organic ammonium ion represented by [N(R ２ ) (R ３ ) ３ ] ＋ R represents a quaternary ammonium cation represented by the formula: ２ R represents an alkyl group having 7 to 20 carbon atoms, or an alkyl group having a substituent and a total of 7 to 20 carbon atoms. ３ each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an alkyl group having a substituent and a total of 1 to 20 carbon atoms. m represents an integer of 1 to 6.}, a solvent (A) having a standard boiling point of 30 to 150°C [however, the solvent of the solvent (A) excludes water.], and a solvent (B) having a standard boiling point of 150 to 300°C, wherein the content of the polythiophene is 0.01 to 25% by weight, the content of the solvent (A) having a standard boiling point of 30 to 150°C is 50 to 99% by weight, and the content of the solvent (B) having a standard boiling point of 150 to 300°C is 0.5 to 30% by weight.

2. The composition of claim 1 , wherein m is 2 or 3.

3. The above R １ The composition of claim 1 , wherein is a methyl group.

4. The composition according to claim 1, wherein the solvent (A) having a normal boiling point of 30 to 150° C. is one single solvent or a mixed solvent of two or more selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-butanol, tert-butyl alcohol, 1-methoxy-2-propanol, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, chlorobenzene, and ethyl acetate.

5. The composition according to claim 1, wherein the solvent (B) having a normal boiling point of 150 to 300° C. is one single solvent or a mixed solvent of two or more selected from the group consisting of 1,3-butanediol, 1,4-butanediol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monopropyl ether, ethylene glycol monohexyl ether, dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, γ-butyrolactone, cyclohexanone, dimethylsulfoxide, and glycerin.

6. A method for producing a conductive polymer film, comprising the steps of: applying a conductive polymer composition containing the composition according to claim 1 onto a support; heating the composition to 40° C. or higher to mainly evaporate the solvent (A); and then increasing the heating temperature to evaporate the solvent (B).

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