JP7499738B2 - Conductive polymer-containing liquid and method for producing same, and conductive laminate and method for producing same - Google Patents

Description

The present invention relates to a conductive polymer-containing liquid containing a π-conjugated conductive polymer and a method for producing the same, as well as a conductive laminate and a method for producing the same.

A π-conjugated conductive polymer, whose main chain is composed of a π-conjugated system, forms a conductive complex by doping with a polyanion having an anionic group, and becomes dispersible in water. A conductive film having a conductive layer can be manufactured by applying a conductive polymer-containing liquid (sometimes called a conductive polymer dispersion) containing the conductive complex to a film substrate or the like. In addition, an epoxy compound may be reacted with the conductive complex in order to increase the wettability of the conductive polymer-containing liquid to the film substrate or to increase the conductivity of the conductive layer to be formed. For example, Patent Document 1 discloses a method of improving the conductivity of a conductive complex by reacting a cyclic epoxy compound.

JP 2020-111650 A

The present invention provides a conductive laminate having a conductive layer with improved conductivity and a manufacturing method for easily manufacturing the same, as well as a conductive polymer-containing liquid used in the manufacturing method and a manufacturing method thereof.

[1] A conductive polymer-containing liquid containing a conductive complex including a π-conjugated conductive polymer and a naphthalenesulfonic acid-based compound represented by the following formula 1, and a dispersion medium:
Formula 1:
RC ₁₀ H ₆ SO ₃ H-(CH ₂ -RC ₁₀ H ₅ SO ₃ H) _n -CH ₂ -RC ₁₀ H ₆ SO ₃ H
[In the formula, each R independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent, and n represents an integer of 1 or more.]
[2] The conductive polymer-containing liquid according to [1], further comprising a polyanion other than the naphthalenesulfonic acid-based compound.
[3] The conductive polymer-containing liquid according to [1] or [2], wherein the naphthalenesulfonic acid-based compound is modified by a reaction with at least one of an epoxy compound, an amine compound, and a quaternary ammonium compound.
[4] The conductive polymer-containing liquid according to any one of [1] to [3], wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene).
[5] The conductive polymer-containing liquid according to [2], wherein the polyanion is polystyrene sulfonic acid.
[6] A method for producing a conductive polymer-containing liquid, comprising polymerizing a monomer that forms a π-conjugated conductive polymer in a reaction liquid containing a naphthalenesulfonic acid-based compound represented by the following formula 1 and a dispersion medium, to obtain a conductive polymer-containing liquid containing a conductive complex containing the π-conjugated conductive polymer and the naphthalenesulfonic acid-based compound, and a dispersion medium.
Formula 1:
RC ₁₀ H ₆ SO ₃ H-(CH ₂ -RC ₁₀ H ₅ SO ₃ H) _n -CH ₂ -RC ₁₀ H ₆ SO ₃ H
[In the formula, each R independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent, and n represents an integer of 1 or more.]
[7] The method for producing a conductive polymer-containing liquid according to [6], further comprising: a polyanion other than the naphthalenesulfonic acid-based compound in the reaction liquid.
[8] The method for producing a conductive polymer-containing liquid according to [6] or [7], comprising reacting the conductive complex with at least one of an epoxy compound, an amine compound, and a quaternary ammonium compound to obtain a conductive polymer-containing liquid containing the obtained reaction product and an organic solvent.
[9] A method for producing a conductive laminate, comprising applying the conductive polymer-containing liquid according to any one of [1] to [5] to at least a part of a surface of a substrate.
[10] A conductive laminate comprising a substrate and a conductive layer formed on at least a portion of the surface of the substrate, the conductive layer being a cured layer of the conductive polymer-containing liquid according to any one of [1] to [5].

According to the conductive polymer-containing liquid of the present invention and the method for producing a conductive laminate using the same, a conductive laminate having a conductive layer with excellent conductivity can be easily produced.
According to the method for producing a conductive polymer-containing liquid of the present invention, the above-mentioned conductive polymer-containing liquid can be easily produced.

This invention is believed to contribute to SDG Goal 12, "Responsible Consumption and Production."

In this specification and claims, the lower and upper limits of the numerical ranges indicated with "~" are considered to be included in the numerical range.

<Conductive polymer-containing liquid>
A first aspect of the present invention is a conductive polymer-containing liquid containing a conductive complex including a π-conjugated conductive polymer and a naphthalenesulfonic acid-based compound represented by formula 1 described below, and a dispersion medium.
In the conductive polymer-containing liquid of this embodiment, the conductive complex may be in a dispersed state or in a dissolved state.

<π-conjugated conductive polymer>
The π-conjugated conductive polymer is not particularly limited as long as it has the effect of the present invention and is an organic polymer whose main chain is composed of a π-conjugated system, and examples thereof include polypyrrole-based conductive polymers, polythiophene-based conductive polymers, polyacetylene-based conductive polymers, polyphenylene-based conductive polymers, polyphenylenevinylene-based conductive polymers, polyaniline-based conductive polymers, polyacene-based conductive polymers, polythiophenevinylene-based conductive polymers, and copolymers thereof. From the viewpoint of stability in air, polypyrrole-based conductive polymers, polythiophenes, and polyaniline-based conductive polymers are preferred, and from the viewpoint of transparency, polythiophene-based conductive polymers are more preferred.

Examples of polythiophene-based conductive polymers include polythiophene, poly(3-methylthiophene), poly(3-ethylthiophene), poly(3-propylthiophene), poly(3-butylthiophene), poly(3-hexylthiophene), poly(3-heptylthiophene), poly(3-octylthiophene), poly(3-decylthiophene), poly(3-dodecylthiophene), poly(3-octadecylthiophene), poly(3-bromothiophene), poly(3-chlorothiophene), and poly(3-iodothiophene). thiophene), poly(3-cyanothiophene), poly(3-phenylthiophene), poly(3,4-dimethylthiophene), poly(3,4-dibutylthiophene), poly(3-hydroxythiophene), poly(3-methoxythiophene), poly(3-ethoxythiophene), poly(3-butoxythiophene), poly(3-hexyloxythiophene), poly(3-heptyloxythiophene), poly(3-octyloxythiophene), poly(3-decyloxythiophene), poly(3-dodecyloxythiophene), oxythiophene), poly(3-octadecyloxythiophene), poly(3,4-dihydroxythiophene), poly(3,4-dimethoxythiophene), poly(3,4-diethoxythiophene), poly(3,4-dipropoxythiophene), poly(3,4-dibutoxythiophene), poly(3,4-dihexyloxythiophene), poly(3,4-diheptyloxythiophene), poly(3,4-dioctyloxythiophene), poly(3,4-didecyloxythiophene), poly(3,4-di dodecyloxythiophene), poly(3,4-ethylenedioxythiophene), poly(3,4-propylenedioxythiophene), poly(3,4-butylenedioxythiophene), poly(3-methyl-4-methoxythiophene), poly(3-methyl-4-ethoxythiophene), poly(3-carboxythiophene), poly(3-methyl-4-carboxythiophene), poly(3-methyl-4-carboxyethylthiophene), and poly(3-methyl-4-carboxybutylthiophene).
Examples of polypyrrole-based conductive polymers include polypyrrole, poly(N-methylpyrrole), poly(3-methylpyrrole), poly(3-ethylpyrrole), poly(3-n-propylpyrrole), poly(3-butylpyrrole), poly(3-octylpyrrole), poly(3-decylpyrrole), poly(3-dodecylpyrrole), poly(3,4-dimethylpyrrole), poly(3,4-dibutylpyrrole), poly(3-carboxypyrrole), poly(3-methyl-4-carboxypyrrole), poly(3-methyl-4-carboxyethylpyrrole), poly(3-methyl-4-carboxybutylpyrrole), poly(3-hydroxypyrrole), poly(3-methoxypyrrole), poly(3-ethoxypyrrole), poly(3-butoxypyrrole), poly(3-hexyloxypyrrole), and poly(3-methyl-4-hexyloxypyrrole).
Examples of polyaniline-based conductive polymers include polyaniline, poly(2-methylaniline), poly(3-isobutylaniline), poly(2-anilinesulfonic acid), and poly(3-anilinesulfonic acid).
Among the above-mentioned π-conjugated conductive polymers, poly(3,4-ethylenedioxythiophene) is particularly preferable from the viewpoints of conductivity, transparency, and heat resistance.
The conductive composite may contain one type of π-conjugated conductive polymer, or two or more types of polymers.

<Naphthalenesulfonic acid compounds>
In a naphthalenesulfonic acid compound represented by the following formula 1 (hereinafter sometimes referred to as compound ₁ ), any one of the hydrogen atoms of naphthalene ( _C10H8 ) is substituted with a substituent R. Adjacent naphthalenes are linked to each other by a methylene group that replaces another arbitrary one of the hydrogen atoms. Each naphthalene in compound 1 has a sulfonic acid group, and is therefore a polyanion.

Formula 1:
RC ₁₀ H ₆ SO ₃ H-(CH ₂ -RC ₁₀ H ₅ SO ₃ H) _n -CH ₂ -RC ₁₀ H ₆ SO ₃ H
[In the formula, each R independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent, and n represents an integer of 1 or more.]
The alkyl group may be linear or branched.
The substituent is arbitrary, and examples thereof include a hydroxyl group, an alkenyl group having 2 to 4 carbon atoms, a halogen atom (such as a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), and an alkoxy group.
The upper limit of n is not particularly limited, and is, for example, approximately 10,000 or less, and preferably 5,000 or less.
The weight average molecular weight of the naphthalenesulfonic acid compound is not particularly limited, and is, for example, preferably from 5,000 to 1,000,000, and more preferably from 10,000 to 500,000. The weight average molecular weight is an average molecular weight based on mass measured by gel permeation chromatography and calculated in terms of polystyrene.

Compound 1 forms a conductive composite by doping a π-conjugated conductive polymer. However, in Compound 1, some of the sulfonic acid groups are not doped into the π-conjugated conductive polymer, and there are excess sulfonic acid groups that are not involved in the doping. Since these excess sulfonic acid groups are hydrophilic groups, the conductive composite has high water dispersibility and low organic solvent dispersibility before reacting with an epoxy compound or an amine compound, as described below.
When the number of all sulfonic acid groups in compound 1 is taken as 100 mol %, the excess sulfonic acid groups are preferably from 30 mol % to 90 mol %, more preferably from 45 mol % to 75 mol %.

In this embodiment, the excess sulfonic acid groups of compound 1 that are not involved in the doping (hereinafter, also referred to as "part of the sulfonic acid groups") may be modified by reaction with one or more compounds selected from the group consisting of epoxy compounds, amine compounds, and quaternary ammonium compounds.
A portion of the sulfonic acid groups of compound 1 reacts with an epoxy compound to form the following substituent (A).
A portion of the sulfonic acid groups of compound 1 reacts with an amine compound to form the following substituent (B).
A portion of the sulfonic acid groups of compound 1 reacts with a quaternary ammonium compound to form the following substituent (C).

(Substituent A)
The substituent (A) is presumed to be a group represented by the following formula (A1) or a group represented by the following formula (A2).

[In formula (A1), R ¹ , R ² , R ³ , and R ⁴ each independently represent a hydrogen atom or any substituent.]

[In formula (A2), m is an integer of 2 or more, a plurality of R ^{5 s} , a plurality of R ^{6 s} , a plurality of R ^{7 s} , and a plurality of R ^{8 s} are each independently a hydrogen atom or any substituent, a plurality of R ⁵ s may be the same or different, a plurality of R ^{6 s} may be the same or different, a plurality of R ⁷ s may be the same or different, and a plurality of R ^{8 s} may be the same or different.]

In formulas (A1) and (A2), the bond at the left end represents that the substituent (A) is substituted with a proton of the sulfonic acid group.

In formula (A1), the optional substituents of R ¹ , R ² , R ³ , and R ⁴ include an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R ¹ and R ³ may be bonded to form a ring which may have a substituent. For example, R ¹ and R ³ may be the above-mentioned hydrocarbon group, and a divalent hydrocarbon group obtained by removing any one hydrogen atom from the monovalent hydrocarbon group of R ¹ and a divalent hydrocarbon group obtained by removing any one hydrogen atom from the monovalent hydrocarbon group of R ³ may be bonded to each other via the carbon atoms from which the hydrogen atoms have been removed to form a ring.
In formula (A2), the optional substituents of R ⁵ , R ⁶ , R ⁷ and R ⁸ include an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. R ⁵ and R ⁷ may be bonded to form a ring which may have a substituent. Examples of the ring are the same as those described above.
Here, the term "optionally substituted" includes both cases where a hydrogen atom (--H) is replaced with a monovalent group and cases where a methylene group (--CH ₂ -) is replaced with a divalent group.
Examples of the monovalent group as a substituent include an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), a trialkoxysilyl group (a trimethoxysilyl group, etc.), and the like.
Examples of the divalent group as a substituent include an oxygen atom (-O-), -C(=O)-, and -C(=O)-O-.
m is an integer of 2 or more, preferably 2 to 100, more preferably 2 to 50, and even more preferably 2 to 25. When m is equal to or more than the lower limit, the hydrophobicity of the conductive composite is sufficiently high. When m is equal to or less than the upper limit, it is possible to prevent the hydrophobicity from becoming too high or the conductivity from decreasing.

The epoxy compound is a compound having one or more epoxy groups in one molecule (an epoxy group-containing compound). From the viewpoint of preventing aggregation or gelation, the epoxy compound is preferably a compound having one epoxy group in one molecule.
The epoxy compound that reacts with the conductive composite may be one type or two or more types.

Examples of monofunctional epoxy compounds having one epoxy group per molecule include ethylene oxide, propylene oxide, 2,3-butylene oxide, isobutylene oxide, 1,2-butylene oxide, 1,2-epoxyhexane, 1,2-epoxyheptane, 1,2-epoxypentane, 1,2-epoxyoctane, 1,2-epoxydecane, 1,3-butadiene monoxide, 1,2-epoxytetradecane, glycidyl methyl ether, 1,2-epoxyoctadecane, 1,2-epoxyhexadecane, ethyl glycidyl ether, glycidyl isopropyl ether, tert-butyl glycidyl ether, 1,2-epoxyeicosane, 2-(chloromethyl)-1,2-epoxypropane, glycidol, epichlorohydrin, epibromohydrin, and butyl glycidyl. ether, 1,2-epoxyhexane, 1,2-epoxy-9-decane, 2-(chloromethyl)-1,2-epoxybutane, 2-ethylhexyl glycidyl ether, 1,2-epoxy-1H,1H,2H,2H,3H,3H-trifluorobutane, allyl glycidyl ether, tetracyanoethylene oxide, glycidyl butyrate, 1,2-epoxycyclooctane, glycidyl methacrylate, 1,2-epoxycyclododecane, 1-methyl-1,2-epoxycyclohexane, 1,2-epoxycyclopentadecane, 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,2-epoxy-1H,1H,2H,2H,3H,3H-heptadecafluorobutane, 3,4-epoxytetrahydrofuran, glycidyl stearate, 3-glycidyloxypropyl trime methoxysilane, epoxysuccinic acid, glycidyl phenyl ether, isophorone oxide, α-pinene oxide, 2,3-epoxynorbornene, benzyl glycidyl ether, diethoxy(3-glycidyloxypropyl)methylsilane, 3-[2-(perfluorohexyl)ethoxy]-1,2-epoxypropane, 1,1,1,3,5,5,5-heptamethyl-3-(3-glycidyloxypropyl)trisiloxane, 9,10-epoxy-1,5-cyclododecadiene, glycidyl 4-tert-butylbenzoate, 2,2-bis(4-glycidyloxyphenyl)propane, 2-tert-butyl-2-[2-(4-chlorophenyl)]ethyloxirane, styrene oxide, glycidyl trityl ether, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-phenylpropylene oxide, cholesterol-5α,6α-epoxide, stilbene oxide, glycidyl p-toluenesulfonate, ethyl 3-methyl-3-phenylglycidate, N-propyl-N-(2,3-epoxypropyl)perfluoro-n-octylsulfonamide, (2S,3S)-1,2-epoxy-3-(tert-butoxycarbonylamino)-4-phenylbutane, (R)-glycidyl 3-nitrobenzenesulfonate, glycidyl 3-nitrobenzenesulfonate, parthenolide, N-glycidylphthalimide, endrin, dieldrin, 4-glycidyloxycarbazole, 7,7-dimethyloctanoic acid [oxiranylmethyl], 1,2-epoxy-4-vinylcyclohexane, higher alcohol glycidyl ethers having 10 to 16 carbon atoms, etc.

The higher alcohol glycidyl ether is preferably one or more higher alcohol glycidyl ethers having 10 to 16 carbon atoms, more preferably one or more higher alcohol glycidyl ethers having 12 to 14 carbon atoms, and even more preferably at least one of C12 (12 carbon atoms) higher alcohol glycidyl ether and C13 (13 carbon atoms) higher alcohol glycidyl ether.

Examples of polyfunctional epoxy compounds having two or more epoxy groups in one molecule include 1,6-hexanediol diglycidyl ether, 1,7-octadiene diepoxide, neopentyl glycol diglycidyl ether, 4-butanediol diglycidyl ether, 1,2:3,4-diepoxybutane, 1,2-cyclohexanedicarboxylate diglycidyl, triglycidyl isocyanurate, neopentyl glycol diglycidyl ether, 1,2:3,4-diepoxybutane, polyethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, propylene ... Examples of such glycidyl ethers include glycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, trimethylolpropane polyglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hexahydrophthalic acid diglycidyl ester, glycerin polyglycidyl ether, diglycerin polyglycidyl ether, polyglycerin polyglycidyl ether, sorbitol-based polyglycidyl ether, and ethylene oxide lauryl alcohol glycidyl ether.

The epoxy compound preferably has a molecular weight of 50 or more and 2000 or less, since this increases the dispersibility in organic solvents. In addition, the epoxy compound preferably has a carbon number of 4 or more and 120 or less, more preferably 7 or more and 100 or less, even more preferably 10 or more and 80 or less, and particularly preferably 15 or more and 50 or less, since this increases the dispersibility in low-polarity hydrocarbon solvents and ester solvents.

(Substituent B)
The substituent (B) is presumed to be a group represented by the following formula (B).

-HN ⁺ R ¹¹ R ¹² R ¹³ ... (B)
[In formula (B), R ¹¹ to R ¹³ each independently represent a hydrogen atom or a hydrocarbon group which may have a substituent, provided that at least one of R ¹¹ to R ¹³ is a hydrocarbon group which may have a substituent.]

In the substituent (B), the bond at the left end represents a bond between the negative charge "-SO ₃ ^- " of the sulfonic acid group and the positive charge of the amine compound.

In the chemical formula (B), R ¹¹ to R ¹³ are a hydrogen atom or a hydrocarbon group which may have a substituent, and R ¹¹ to R ¹³ in the chemical formula (B) are substituents derived from an amine compound described below.
Examples of the hydrocarbon group in chemical formula (B) include an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.
Examples of the aliphatic hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
Examples of the substituent on the aliphatic hydrocarbon group include a phenyl group and a hydroxyl group.
Examples of the aromatic hydrocarbon group include a phenyl group and a naphthyl group.
Examples of the substituent on the aromatic hydrocarbon group include an alkyl group having 1 to 5 carbon atoms and a hydroxyl group.

The amine compound is at least one selected from the group consisting of primary amines, secondary amines, and tertiary amines. The amine compound that reacts with the conductive composite may be one type or two or more types.
Examples of primary amines include aniline, toluidine, benzylamine, and ethanolamine.
Examples of secondary amines include diethanolamine, dimethylamine, diethylamine, dipropylamine, diphenylamine, dibenzylamine, and dinaphthylamine.
Examples of tertiary amines include triethanolamine, trimethylamine, triethylamine, tripropylamine, tributylamine, trihexylamine, trioctylamine, triphenylamine, tribenzylamine, and trinaphthylamine.
Among the amine compounds, tertiary amines are preferred because they can increase the electrical conductivity of the conductive composite of this embodiment, and at least one of trioctylamine and tributylamine is more preferred.

In order to improve dispersibility in organic solvents, particularly in low-polarity hydrocarbon solvents and ester solvents, the amine compound preferably has a substituent on the nitrogen atom having 4 or more carbon atoms, more preferably has a substituent on the nitrogen atom having 6 or more carbon atoms, and even more preferably has a substituent on the nitrogen atom having 8 or more carbon atoms. The upper limit of the carbon number of the substituent on the nitrogen atom is not particularly limited, and taking into consideration solubility in solvents and reactivity, it is, for example, preferably 50 or less, more preferably 40 or less, and even more preferably 30 or less.
The total number of carbon atoms of R ¹¹ to R ¹³ contained in the amine compound is preferably 6 to 33, more preferably 9 to 30, and even more preferably 12 to 27.
The number of carbon atoms in each of the substituents on the nitrogen atom may be the same or different.

When the conductive complex has a substituent (A) and a substituent (B), the mass ratio represented by [substituent (A)]:[substituent (B)] (hereinafter also referred to as the A/B ratio) is preferably 10:90 to 90:10, more preferably 20:80 to 80:20, and even more preferably 25:75 to 75:25. When the A/B ratio is within the above range, it is easy to balance the dispersibility and the conductivity. The mass of [substituent (A)] can be calculated by [(mass of reactant A obtained by reacting an epoxy compound with a conductive complex) - (mass of the conductive complex before reacting with an epoxy compound)]. The mass of [substituent (B)] can be calculated by [(mass of reactant B obtained by reacting the reactant A with an amine compound) - (mass of the reactant A)].

(Substituent C)
The substituent (C) is presumed to be a group represented by the following formula (C).

-N ⁺ R ¹¹ R ¹² R ¹³ R ¹⁴ ... (C)
[In formula (C), R ¹¹ to R ¹⁴ each independently represent a hydrocarbon group which may have a substituent.]

In the substituent (C), the bond at the left end represents a bond between the negative charge "-SO ₃ ^- " of the sulfonic acid group and the positive charge of the quaternary ammonium cation.

In the chemical formula (C), R ¹¹ to R ¹⁴ are hydrocarbon groups which may have a substituent.
In chemical formula (C), R ¹¹ to R ¹⁴ are substituents derived from a quaternary ammonium compound.
Examples of the hydrocarbon group in chemical formula (C) include an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.
Examples of the aliphatic hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
Examples of the substituent on the aliphatic hydrocarbon group include a phenyl group and a hydroxyl group.
Examples of the aromatic hydrocarbon group include a phenyl group and a naphthyl group.
Examples of the substituent on the aromatic hydrocarbon group include an alkyl group having 1 to 5 carbon atoms and a hydroxyl group.

In order to improve dispersibility in organic solvents and conductivity, the quaternary ammonium compound preferably has a substituent on the nitrogen atom having 3 or more carbon atoms, more preferably has a substituent on the nitrogen atom having 5 or more carbon atoms, and even more preferably has a substituent on the nitrogen atom having 7 or more carbon atoms. The upper limit of the carbon number of each substituent on the nitrogen atom is not particularly limited, and taking into consideration solubility in solvents and reactivity, it is, for example, preferably 40 or less, more preferably 30 or less, and even more preferably 20 or less.
The total number of carbon atoms of R ¹¹ to R ¹⁴ in the quaternary ammonium compound is preferably 8-44, more preferably 12-40, and even more preferably 16-36.
The number of carbon atoms in each of the substituents on the nitrogen atom may be the same or different.

Specific examples of the quaternary ammonium compound include quaternary ammonium salts such as tetramethylammonium salt, tetraethylammonium salt, tetrapropylammonium salt, tetrabutylammonium salt, tetra-n-octylammonium salt, tetraphenylammonium salt, tetrabenzylammonium salt, and tetranaphthylammonium salt.
Examples of the counter anion of the ammonium cation include halogen ions such as bromide ion and chloride ion, and hydroxy ion.

When the conductive complex has a substituent (A) and a substituent (C), the mass ratio represented by [substituent (A)]:[substituent (C)] (hereinafter also referred to as the A/C ratio) is preferably 10:90 to 90:10, more preferably 20:80 to 80:20, and even more preferably 25:75 to 75:25. When the A/C ratio is within the above range, it is easy to balance the dispersibility and the conductivity. The mass of [substituent (A)] can be calculated by [(mass of reactant A obtained by reacting an epoxy compound with a conductive complex) - (mass of the conductive complex before reacting with an epoxy compound)]. The mass of [substituent (C)] can be calculated by [(mass of reactant C obtained by reacting the reactant A with a quaternary ammonium compound) - (mass of the reactant A)].

The content ratio of compound 1 in the conductive complex is preferably in the range of 1 part by mass or more and 1,000 parts by mass or less, more preferably 10 parts by mass or more and 700 parts by mass or less, and even more preferably 100 parts by mass or more and 500 parts by mass or less, relative to 100 parts by mass of the π-conjugated conductive polymer.
When the content of compound 1 is equal to or more than the lower limit, the doping effect on the π-conjugated conductive polymer tends to be stronger, resulting in higher conductivity. On the other hand, when the content of compound 1 is equal to or less than the upper limit, the amount of sulfonic acid groups not involved in doping is appropriately suppressed, and the sulfonic acid groups can be easily converted to hydrophobicity when reacting with an epoxy compound, an amine compound, or a quaternary ammonium compound.

The content of the conductive complex relative to the total mass of the conductive polymer-containing liquid of this embodiment is, for example, preferably 0.01 mass % or more and 10 mass % or less, more preferably 0.1 mass % or more and 3 mass % or less, and even more preferably 0.2 mass % or more and 1 mass % or less.
When the content is at least as large as the lower limit of the above range, the conductivity of the conductive layer formed by applying the conductive polymer-containing liquid can be further improved.
When the content is equal to or less than the upper limit of the above range, the dispersibility of the conductive complex in the conductive polymer-containing liquid is improved, and a uniform conductive layer can be formed.

<Polyanions other than Compound 1>
The conductive polymer-containing liquid of this embodiment may further contain a polyanion other than Compound 1 (hereinafter, sometimes simply referred to as "polyanion"). The polyanion can be doped into a π-conjugated conductive polymer to form a conductive complex. Therefore, the conductive complex of this embodiment may be a binary conductive complex of a π-conjugated conductive polymer and Compound 1, or a ternary conductive complex of a π-conjugated conductive polymer, Compound 1, and a polyanion. Some anion groups of the polyanion can form the substituents (A), (B), and (C) in the same manner as the above-mentioned sulfonic acid group.

The polyanion of this embodiment is a polymer having two or more monomer units each having an anionic group in the molecule. The anionic group of the polyanion functions as a dopant for the π-conjugated conductive polymer, and can improve the conductivity of the π-conjugated conductive polymer.
The anion group of the polyanion is preferably a sulfo group or a carboxy group.
Specific examples of such polyanions include polymers having a sulfo group, such as polystyrene sulfonic acid, polyvinyl sulfonic acid, polyallyl sulfonic acid, polyacrylic acid esters having a sulfo group, polymethacrylic acid esters having a sulfo group (for example, poly(4-sulfobutyl methacrylate, polysulfoethyl methacrylate, polymethacryloyloxybenzenesulfonic acid), poly(2-acrylamido-2-methylpropanesulfonic acid), and polyisoprene sulfonic acid; and polymers having a carboxy group, such as polyvinyl carboxylic acid, polystyrene carboxylic acid, polyallyl carboxylic acid, polyacrylic acid, polymethacrylic acid, poly(2-acrylamido-2-methylpropanecarboxylic acid), and polyisoprene carboxylic acid. These may be homopolymers or copolymers of two or more kinds.
Among these polyanions, polymers having a sulfo group are preferred, and polystyrene sulfonic acid is more preferred, since they can provide higher electrical conductivity.
The polyanion may be of one type or of two or more types.
The mass average molecular weight of the polyanion is preferably from 20,000 to 1,000,000, and more preferably from 100,000 to 500,000. The mass average molecular weight is the average molecular weight based on mass measured by gel permeation chromatography and calculated in terms of polystyrene.

When a polyanion forms a conductive complex by doping a π-conjugated conductive polymer, it is considered that some anion groups in the polyanion are not doped into the π-conjugated conductive polymer and have excess anion groups that are not involved in the doping. Since these excess anion groups are hydrophilic groups, as described above, they have high water dispersibility and low organic solvent dispersibility before reacting with an epoxy compound, an amine compound, or a quaternary ammonium compound.
When the number of all anionic groups in the polyanion is taken as 100 mol %, the excess anionic groups are preferably from 30 mol % to 90 mol %, and more preferably from 45 mol % to 75 mol %.

[Dispersion medium]
Examples of the dispersion medium contained in the conductive polymer-containing liquid of this embodiment include water, an organic solvent, and a mixture of water and an organic solvent.

The dispersion medium contained in the conductive polymer-containing liquid of this embodiment is preferably an aqueous dispersion medium when the conductive complex is hydrophilic (when the part of the sulfonic acid groups is not modified). Here, the aqueous dispersion medium is water or a mixture of water and a water-soluble organic solvent. The content of water relative to the total mass of the aqueous dispersion medium is 50 mass% or more, preferably 60 mass% or more, more preferably 80 mass% or more, and may be 100 mass%.
When the conductive composite is hydrophobic, the content of the organic solvent relative to the total mass of the dispersion medium is preferably 70% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, and even more preferably 90% by mass or more and 100% by mass or less.

<Organic Solvent>
Examples of the organic solvent include alcohol-based solvents, ether-based solvents, ketone-based solvents, ester-based solvents, hydrocarbon-based solvents, nitrogen atom-containing compound-based solvents, etc. The organic solvent may be one type or two or more types.

The organic solvent may be a water-soluble organic solvent or a water-insoluble organic solvent.
Here, the water-soluble organic solvent is an organic solvent that dissolves in an amount of 1 g or more in 100 g of water at 20° C., and the water-insoluble organic solvent is an organic solvent that dissolves in an amount of less than 1 g in 100 g of water at 20° C. The water-soluble organic solvent is preferably one or more selected from alcohol-based solvents.

Examples of alcohol-based solvents include monohydric alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 2-methyl-2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, allyl alcohol, propylene glycol monomethyl ether, and ethylene glycol monomethyl ether; and dihydric alcohols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butanediol.
Examples of the ether solvent include diethyl ether, dimethyl ether, and propylene glycol dialkyl ether.
Examples of the ketone solvent include diethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, methyl amyl ketone, diisopropyl ketone, methyl ethyl ketone, acetone, and diacetone alcohol.
Examples of the ester-based solvents and the hydrocarbon-based solvents will be described later.
Examples of the nitrogen atom-containing compound solvent include N-methylpyrrolidone, dimethylacetamide, and dimethylformamide.
An example of a solvent not classified into the above categories is dimethyl sulfoxide.

(Ester solvent)
The ester solvent is an ester group-containing compound having an ester group (-C(=O)-O-).
When the conductive complex is modified by a reaction with an epoxy compound and an amine compound or a quaternary ammonium compound, it is preferable that the organic solvent contains an ester-based solvent, since this further enhances the dispersibility of the conductive complex.
From the viewpoint of improving the dispersibility of the conductive composite, it is preferable to contain one or more ester solvents represented by the following formula 1z.
Formula 1z: R ²¹ —C(═O)—O—R ²²
[In the formula, R ²¹ represents a hydrogen atom, a methyl group, or an ethyl group, and R ²² represents a linear or branched alkyl group having 1 to 6 carbon atoms.]

From the viewpoint of improving the dispersibility of the conductive composite, R ²¹ is preferably a methyl group or an ethyl group, more preferably a methyl group, and R ²² preferably has 2 to 5 carbon atoms, more preferably 2 to 4 carbon atoms.

Examples of ester-based solvents include ethyl acetate, propyl acetate, butyl acetate, isopropyl acetate, and isobutyl acetate.

The content of the ester-based solvent contained in the organic solvent is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, even more preferably 70% by mass or more, particularly preferably 80% by mass or more, most preferably 90% by mass or more, and may be 100% by mass, based on the total mass of the organic solvent. When the content of the ester-based solvent is within the above range, the dispersibility of the conductive composite can be improved.

When the conductive polymer-containing liquid of this embodiment contains an ester-based solvent, it may further contain one or more organic solvents other than the ester-based solvent.
Examples of organic solvents other than ester-based solvents include the hydrocarbon-based solvents described below, the ketone-based solvents, alcohol-based solvents, and nitrogen atom-containing compound-based solvents described above.

(Hydrocarbon solvent)
In the case where the conductive complex contained in the conductive polymer-containing liquid of this embodiment is modified by a reaction with an epoxy compound and an amine compound or a quaternary ammonium compound, it is preferable to include a hydrocarbon-based solvent as a dispersion medium, since this increases the wettability with respect to the plastic film substrate and makes it easy to add a binder component with low polarity.

Examples of the hydrocarbon solvent include aliphatic hydrocarbon solvents and aromatic hydrocarbon solvents. Examples of the aliphatic hydrocarbon solvent include pentane, hexane, heptane, octane, decane, cyclohexane, and methylcyclohexane. Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene, ethylbenzene, propylbenzene, and isopropylbenzene. Among these, toluene is preferred because it has high dispersibility of the conductive composite. In addition, when a silicone compound is added as a binder component, at least one of heptane and toluene is preferred because it has excellent solubility of the silicone compound.

In addition to the hydrocarbon solvent, it is preferable to further contain methyl ethyl ketone, since this further increases the dispersibility of the conductive composite. For example, the amount of methyl ethyl ketone is preferably 20 parts by mass or more and 120 parts by mass or less, more preferably 30 parts by mass or more and 100 parts by mass or less, and even more preferably 40 parts by mass or more and 80 parts by mass or less, per 100 parts by mass of the hydrocarbon solvent.

The content of the hydrocarbon-based solvent is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, even more preferably 70% by mass or more, particularly preferably 80% by mass or more, most preferably 90% by mass or more, and may be 100% by mass, based on the total mass of the organic solvent. When the content of the hydrocarbon-based solvent is within the above range, the dispersibility of the conductive composite can be improved.

When the conductive polymer-containing liquid of this embodiment contains a hydrocarbon-based solvent, it may further contain one or more organic solvents other than the hydrocarbon-based solvent.
Examples of organic solvents other than hydrocarbon solvents include the above-mentioned ketone solvents, alcohol solvents, ester solvents, and nitrogen atom-containing compound solvents.

<Addition of binder components>
The conductive polymer-containing liquid of this embodiment may further contain a binder component. By using a conductive polymer-containing liquid containing a binder component, the strength of the conductive layer to be formed can be improved and adhesiveness and releasability can be imparted.
The binder component is a resin or a precursor thereof other than the π-conjugated conductive polymer, Compound 1, and the polyanion, and is a thermoplastic resin, or a curable monomer or oligomer that is cured when the conductive layer is formed. The thermoplastic resin becomes the binder resin as it is, and the curable monomer or oligomer becomes the resin formed by curing.
The binder component may be a pressure-sensitive adhesive, which will be described later.
In this embodiment, the binder component to be added may be one type or two or more types.

Specific examples of binder resins derived from binder components include epoxy resins, acrylic resins (acrylic compounds), polyester resins, polyurethane resins, polyimide resins, polyether resins, melamine resins, silicones, etc.

The curable monomer or oligomer may be a thermosetting monomer or oligomer, or a photocurable monomer or oligomer. Here, the oligomer refers to a polymer having a mass average molecular weight of less than 10,000.
Examples of the curable monomer include an acrylic monomer (acrylic compound), an epoxy monomer, an organosiloxane, etc. Examples of the curable oligomer include an acrylic oligomer (acrylic compound), an epoxy oligomer, a silicone oligomer (curable silicone), etc.
When an acrylic monomer or an acrylic oligomer is used as the binder component, it can be easily cured by heating or irradiating with light.

When a curable monomer or oligomer is included, it is preferable to further include a curing catalyst. For example, when a thermosetting monomer or oligomer is included, it is preferable to include a thermal polymerization initiator that generates radicals by heating, and when a photocurable monomer or oligomer is included, it is preferable to include a photopolymerization initiator that generates radicals by light irradiation.

The content ratio of the binder component (excluding the silicone compound described later) contained in the conductive polymer-containing liquid of this embodiment is, for example, preferably 1 part by mass or more and 10,000 parts by mass or less, more preferably 10 parts by mass or more and 5,000 parts by mass or less, and even more preferably 100 parts by mass or more and 1,000 parts by mass or less, relative to 1 part by mass of the conductive composite.
When the content is equal to or greater than the lower limit of the above range, the characteristics of the binder component contained in the conductive layer formed from the conductive polymer-containing liquid of this embodiment can be fully exhibited.
When it is equal to or less than the upper limit of the above range, sufficient conductivity of the conductive layer formed from the conductive polymer-containing liquid of this embodiment can be ensured.

(Silicone Compound)
In the case where the dispersion medium of the conductive polymer-containing liquid of this embodiment contains a hydrocarbon-based solvent or an ester-based solvent, the dispersibility of the silicone compound is preferably further improved.
Examples of the silicone compound include curable silicone. When the binder component is curable silicone, releasability can be imparted to the conductive layer by curing the curable silicone.

The curable silicone may be either an addition curable silicone or a condensation curable silicone. In this embodiment, the addition curable silicone is preferred because it is less likely to cause curing inhibition.

The addition curing silicone may be a linear polymer having a siloxane bond, which includes polydimethylsiloxane having vinyl groups at both ends of the linear chain, and hydrogen silane. Such addition curing silicone forms a three-dimensional crosslinked structure by addition reaction and cures. A platinum-based curing catalyst may be used to accelerate the cure.
Specific examples of addition curing silicones include KS-3703T, KS-847T, KM-3951, X-52-151, X-52-6068, and X-52-6069 (manufactured by Shin-Etsu Chemical Co., Ltd.).
The addition curing type silicone is preferably dissolved or dispersed in an organic solvent.

The content ratio of the silicone compound contained in the conductive polymer-containing liquid of this embodiment is preferably 10 parts by mass or more and 10,000 parts by mass or less, more preferably 100 parts by mass or more and 5,000 parts by mass or less, and even more preferably 500 parts by mass or more and 3,000 parts by mass or less, relative to 100 parts by mass of the conductive composite.
When the content is equal to or greater than the lower limit of the above range, sufficient releasability can be imparted to the conductive layer formed from the conductive polymer-containing liquid of this embodiment.
When it is equal to or less than the upper limit of the above range, sufficient conductivity of the conductive layer formed from the conductive polymer-containing liquid of this embodiment can be ensured.

[Adhesive]
The conductive polymer-containing liquid of this embodiment may contain an adhesive as a binder component. By using a conductive polymer-containing liquid containing an adhesive, a conductive layer having adhesive properties can be formed.
When the dispersion medium of the conductive polymer-containing liquid of this embodiment contains a hydrocarbon-based solvent or an ester-based solvent, it can be easily mixed with a pressure-sensitive adhesive that has been dispersed in advance in a hydrocarbon-based solvent or an ester-based solvent, and the conductive complex can be stably dispersed in the mixed liquid, which is preferable.

The degree of adhesiveness of the adhesive is not particularly limited, and may be adhesive enough to be easily peeled off by hand after application, or adhesive enough to be difficult to peel off after application. Adhesiveness that is difficult to peel off can be rephrased as adhesiveness. In other words, the adhesiveness may be such that it is possible to adhere semi-permanently.

Any known adhesive can be used as the adhesive. Acrylic adhesives are preferred from the viewpoint of maintaining electrical conductivity while providing good adhesive properties.

(Acrylic adhesive)
The acrylic adhesive can bond and integrate surfaces of the same or different solids. The acrylic adhesive contains an acrylic resin (acrylic polymer).

Specific examples of acrylic monomers that form acrylic resins include acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-methoxyethyl acrylate, ditrimethylolpropane tetraacrylate, 2-hydroxy-3-phenoxypropyl acrylate, bisphenol A/ethylene oxide modified diacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, dipentaerythritol tetra ... Acrylates such as pentaerythritol monohydroxypentaacrylate, dipropylene glycol diacrylate, trimethylolpropane triacrylate, glycerol propoxy triacrylate, 4-hydroxybutyl acrylate, 1,6-hexanediol diacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, isobornyl acrylate, polyethylene glycol diacrylate, pentaerythritol triacrylate, tetrahydrofurfuryl acrylate, and tripropylene glycol diacrylate; ethylene glycol dimethacrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, allyl methacrylate, 1,3-butylene glycol dimethacrylate, benzyl methacrylate, cyclohexyl methacrylate, diethylene glycol dimethacrylate, 2-ethylhexyl methacrylate, glycidyl methacrylate, 1,6-hexanediol dimethacrylate, 2-hydroxyethyl methacrylate, isobornyl methacrylate, lauryl methacrylate, phenoxyethyl methacrylate, tetrahydrofuran, Examples of the methacrylates include methacrylates such as drolofurfuryl methacrylate and trimethylolpropane trimethacrylate; and (meth)acrylamides such as diacetone acrylamide, N,N-dimethylacrylamide, dimethylaminopropyl acrylamide, dimethylaminopropyl methacrylamide, methacrylamide, N-methylolacrylamide, acryloylformoline, N-methylacrylamide, N-isopropylacrylamide, N-t-butylacrylamide, N-phenylacrylamide, acryloylpiperidine, and 2-hydroxyethylacrylamide.
The acrylic resin may be formed of one type of acrylic monomer or two or more types of acrylic monomers. By combining two or more types of acrylic monomers, the adhesiveness can be adjusted.

The acrylic resin may be a copolymer of an acrylic monomer and a vinyl monomer other than the acrylic monomer.
Examples of vinyl monomers include styrene, α-methylstyrene, vinyl acetate, acrylonitrile, methacrylonitrile, and maleic anhydride.
The content of the acrylic monomer unit in the copolymer is preferably 50 mol % or more and less than 100 mol %, and more preferably 70 mol % or more and 98 mol % or less.
When the content of the acrylic monomer unit is equal to or more than the lower limit, adhesiveness can be easily exhibited.
The content of the vinyl monomer unit in the copolymer can be, for example, from 2 mol % to 20 mol %.

The glass transition temperature of the acrylic resin is preferably 80° C. or lower, more preferably 50° C. or lower, and even more preferably 0° C. or lower. An acrylic resin having a glass transition temperature of more than 80° C. has low adhesion. The glass transition temperature of an acrylic resin is −80° C. or higher, and it is difficult to obtain an acrylic resin having a glass transition temperature lower than that. The glass transition temperature of an acrylic resin can be determined by differential scanning calorimetry or dynamic viscoelasticity measurement.
Examples of acrylic monomers that tend to lower the glass transition temperature of acrylic resins include ethyl acrylate, butyl acrylate (particularly n-butyl acrylate), 2-ethylhexyl acrylate, etc. In an acrylic resin, the higher the ratio of these monomer units, the lower the glass transition temperature.

The mass average molecular weight of the acrylic resin is preferably 10,000 to 2,000,000, and more preferably 30,000 to 1,000,000. If the mass average molecular weight of the acrylic resin is equal to or greater than the lower limit, sufficient cohesive strength can be ensured. If it is equal to or less than the upper limit, adhesion can be further improved.

When the acrylic resin has an acrylic monomer unit having a reactive functional group, it may be cured by reacting with a curing agent. When the acrylic resin is cured, the cohesive force of the conductive layer containing the adhesive is improved, and the strength can be improved. In addition, by improving the cohesive force of the conductive layer, it is possible to make the conductive layer removably capable of repeated adhesion and peeling.
Examples of the reactive functional group include a hydroxy group, a carboxy group, an amino group, an amide group, an epoxy group, etc. In the case of reacting with a polyfunctional isocyanate described later, the reactive functional group is preferably a hydroxy group, a carboxy group, or an amino group, and more preferably a hydroxy group.
Examples of acrylic monomers having a hydroxy group include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, and 4-hydroxybutyl methacrylate.
Examples of the acrylic monomer having a carboxy group include acrylic acid, methacrylic acid, and itaconic acid.
Examples of the acrylic monomer having an amino group include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, and diethylaminoethyl methacrylate.
Examples of acrylic monomers having an amide group include acrylamide, methacrylamide, N-methylol acrylamide, and N-methylol methacrylamide.
Examples of the acrylic monomer having an epoxy group include glycidyl acrylate and glycidyl methacrylate.
When a polyfunctional isocyanate is used as a curing agent, among the acrylic monomers having a reactive functional group, taking into consideration curability and cost, an acrylic monomer having a hydroxy group is preferred, and 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate are more preferred.
The acrylic monomer having a reactive functional group that forms the acrylic resin may be of one type or of two or more types.

The content of the adhesive contained in the conductive polymer-containing liquid of this embodiment is preferably 10 parts by mass or more and 10,000 parts by mass or less, more preferably 100 parts by mass or more and 5,000 parts by mass or less, and even more preferably 300 parts by mass or more and 1,000 parts by mass or less, relative to 1 part by mass of the conductive composite.
When it is equal to or greater than the lower limit of the above range, sufficient adhesion can be imparted to the conductive layer formed by the conductive polymer-containing liquid of this embodiment.
When it is equal to or less than the upper limit of the above range, sufficient conductivity of the conductive layer formed from the conductive polymer-containing liquid of this embodiment can be ensured.

(Hardening agent)
When the adhesive contained in the conductive polymer-containing liquid of this embodiment has a reactive functional group, the conductive polymer-containing liquid of this embodiment preferably contains a curing agent.
Examples of the curing agent include isocyanate-based curing agents such as polyfunctional isocyanates having two or more isocyanate groups in one molecule, and epoxy-based curing agents such as epoxy compounds having two or more epoxy groups in one molecule. Among these curing agents, polyfunctional isocyanates are preferred from the viewpoint of reactivity. In particular, when the adhesive has an acrylic monomer unit having a hydroxyl group, it is preferred that the curing agent is a polyfunctional isocyanate.

Examples of the polyfunctional isocyanate include aliphatic polyfunctional isocyanates, alicyclic polyfunctional isocyanates, and aromatic polyfunctional isocyanates.
Specific examples of polyfunctional isocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, polyphenylene polymethylene polyisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, p-phenylene diisocyanate, transcyclohexane 1,4-diisocyanate, 4,4'-dicyclomethane diisocyanate, 3, Examples of the isocyanate include 3'-dimethyl-4,4'-diphenylmethane diisocyanate, dianisidine diisocyanate, m-xylylene diisocyanate, isophorone diisocyanate, 1,5-naphthalene diisocyanate, 1,4-cyclohexane diisocyanate, lysine diisocyanate, lysine ester triisocyanate, tetramethylxylene diisocyanate, 1,6,11-undecane triisocyanate, 1,3,6-hexamethylene triisocyanate, bicyclohepta triisocyanate, and trimethylhexamethylene diisocyanate.
The polyfunctional isocyanate may be a modified diisocyanate formed from a modified polyfunctional isocyanate obtained by modifying the diisocyanate so that the NCO/OH molar ratio becomes 2/1 or more.
The polyfunctional isocyanate may be a modified polyisocyanate. Examples of the modified polyisocyanate include polyurethane polyisocyanates obtained by reacting the polyfunctional isocyanate with a polyhydric alcohol, polyisocyanates containing an isocyanurate ring obtained by polymerizing a polyfunctional isocyanate, and polyisocyanates containing a biuret bond obtained by reacting a polyfunctional isocyanate with water.
The type of curing agent contained in the conductive polymer-containing liquid of this embodiment may be one type or two or more types.

The content ratio of the curing agent contained in the conductive polymer-containing liquid of this embodiment is, for example, preferably 1 part by mass or more and 100 parts by mass or less, more preferably 2 parts by mass or more and 50 parts by mass or less, and even more preferably 3 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the adhesive.
When the content is within the above range, sufficient adhesion can be imparted to the conductive layer formed by the conductive polymer-containing liquid of this embodiment.

(Highly conductive agent)
The conductive polymer-containing liquid of this embodiment may contain a conductivity enhancing agent.
Here, the above-mentioned π-conjugated conductive polymer, polyanion, compound 1, organic solvent, adhesive, curing agent, and binder component are not classified as a high-conductivity agent. Note that the epoxy compound, the amine compound, and the quaternary ammonium compound may be included in the high-conductivity agent described here.
The conductive agent is preferably at least one compound selected from the group consisting of saccharides, nitrogen-containing aromatic cyclic compounds, compounds having two or more hydroxyl groups, compounds having one or more hydroxyl groups and one or more carboxyl groups, compounds having an amide group, compounds having an imide group, lactam compounds, and compounds having a glycidyl group.
The conductive polymer-containing liquid of this embodiment may contain one type of highly conductive agent, or two or more types of highly conductive agents.
The content of the high-conductivity agent is preferably 1 part by mass or more and 10,000 parts by mass or less, more preferably 10 parts by mass or more and 5,000 parts by mass or less, and even more preferably 100 parts by mass or more and 2,500 parts by mass or less, relative to 100 parts by mass of the conductive complex.
When the content ratio of the conductive agent is equal to or more than the lower limit, the effect of improving the conductivity by adding the conductive agent is sufficiently exhibited, and when the content ratio is equal to or less than the upper limit, a decrease in the conductivity caused by a decrease in the concentration of the π-conjugated conductive polymer can be prevented.

(Other additives)
The conductive polymer-containing liquid of this embodiment may contain other known additives.
The additives are not particularly limited as long as the effects of the present invention can be obtained. For example, surfactants, inorganic conductive agents, antifoaming agents, coupling agents, antioxidants, ultraviolet absorbing agents, etc. can be used.
The surfactant may be a nonionic, anionic or cationic surfactant, with the nonionic surfactant being preferred from the standpoint of storage stability. A polymer surfactant such as polyvinylpyrrolidone may also be added.
Examples of the inorganic conductive agent include metal ions, conductive carbon, etc. Metal ions can be generated by dissolving a metal salt in water.
The antifoaming agent includes silicone resin, polydimethylsiloxane, silicone oil, and the like.
The coupling agent may be a silane coupling agent having a vinyl group or an amino group.
Examples of the antioxidant include phenol-based antioxidants, amine-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and sugars.
Examples of the ultraviolet absorber include benzotriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, salicylate-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers, oxanilide-based ultraviolet absorbers, hindered amine-based ultraviolet absorbers, and benzoate-based ultraviolet absorbers.
When the conductive polymer-containing liquid of this embodiment contains the above-mentioned additive, the content ratio thereof is appropriately determined depending on the type of additive, but can be, for example, in the range of 0.001 parts by mass or more and 5 parts by mass or less per 100 parts by mass of the conductive composite.

<Method for producing conductive polymer-containing liquid>
A second aspect of the present invention is a method for producing a conductive polymer-containing liquid, which comprises polymerizing a monomer that forms a π-conjugated conductive polymer in a reaction liquid containing a naphthalenesulfonic acid-based compound (compound 1) represented by formula 1 and a dispersion medium (polymerization step) to obtain a conductive polymer-containing liquid containing a conductive complex containing the π-conjugated conductive polymer and the naphthalenesulfonic acid-based compound, and a dispersion medium.
According to the production method of this embodiment, the conductive polymer-containing liquid of the first embodiment can be produced.

[Polymerization process]
The dispersion medium constituting the reaction liquid is preferably an aqueous dispersion medium containing water.
The content ratio of water relative to the total mass of the dispersion medium is, for example, preferably 60% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 100% by mass or less, even more preferably 80% by mass or more and 100% by mass or less, and particularly preferably 90% by mass or more and 100% by mass or less.
As the dispersion medium other than water, the above-mentioned water-soluble organic solvents are preferable.

The π-conjugated conductive polymer can be obtained by chemically oxidizing and polymerizing the monomer.
The chemical oxidative polymerization of the monomers may be carried out in the same manner as known methods.
It is preferable to add an appropriate amount of a known catalyst and oxidizing agent to the reaction liquid.
Examples of the catalyst include transition metal compounds such as ferric chloride, ferric sulfate, ferric nitrate, and cupric chloride. These catalysts can be added in an amount of, for example, 0.01% by mass or more and 0.05% by mass or less with respect to the total mass of the reaction liquid.
Examples of the oxidizing agent include persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate. The oxidizing agent can return the reduced catalyst to its original oxidized state. These oxidizing agents can be added in an amount of, for example, 0.1% by mass to 2% by mass based on the total mass of the reaction solution.

The content of compound 1 relative to the total mass of the reaction liquid is, for example, preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.3% by mass or more and 5% by mass or less, and even more preferably 0.6% by mass or more and 3% by mass or less.
When the amount is within the above range, the compound 1 can be sufficiently doped into the π-conjugated conductive polymer to be synthesized, and the amount of excess compound 1 that is not involved in the doping at all can be reduced, so that a conductive composite with excellent conductivity can be synthesized.

The content of the monomer relative to the total mass of the reaction liquid is, for example, preferably 0.05% by mass or more and 2% by mass or less, more preferably 0.1% by mass or more and 1.0% by mass or less, and even more preferably 0.2% by mass or more and 0.8% by mass or less.
When the amount falls within the above range, the π-conjugated conductive polymer to be synthesized can be sufficiently doped with Compound 1, and a conductive composite having excellent conductivity can be synthesized.

The mass ratio (m2/m1) of the content m1 of the monomer to the content m2 of the compound 1 immediately before polymerization in the reaction liquid is preferably 1 or more and 5 or less, more preferably 1.5 or more and 4 or less, and even more preferably 2 or more and 3.5 or less.
When the content is within the above range, the compound 1 is sufficiently doped into the resulting π-conjugated conductive polymer, and a conductive composite having excellent dispersibility in aqueous dispersions is obtained due to the sufficient presence of a portion of sulfonic acid groups that are not involved in doping. In addition, the conductive layer formed using the conductive polymer-containing liquid containing the obtained conductive composite has excellent conductivity.

The reaction solution may contain a polyanion other than Compound 1. By polymerizing the monomers in the presence of Compound 1 and the polyanion, a ternary conductive composite is obtained.
The total content of compound 1 and the polyanion relative to the total mass of the reaction solution is, for example, preferably 0.1 mass% or more and 10 mass% or less, more preferably 0.3 mass% or more and 5 mass% or less, and even more preferably 0.6 mass% or more and 3 mass% or less.
When the amount is within the above range, the compound 1 and the polyanion can be sufficiently doped into the π-conjugated conductive polymer to be synthesized, and the excess compound 1 and the polyanion that are not involved in the doping at all can be reduced, so that a conductive composite with excellent conductivity can be synthesized.

The mass ratio (m3/m1) of the content m1 of the monomer immediately before polymerization in the reaction solution to the total content m3 of the compound 1 and the polyanion is preferably 1 or more and 5 or less, more preferably 1.5 or more and 4 or less, and even more preferably 2 or more and 3.5 or less.
When the content is within the above range, the respective contents are well balanced, the compound 1 and the polyanion are sufficiently doped into the resulting π-conjugated conductive polymer, and a conductive composite having excellent dispersibility in aqueous dispersions is obtained due to the sufficient presence of some sulfonic acid groups (in other words, some anion groups) that are not involved in the doping. In addition, the conductive layer formed using the conductive polymer-containing liquid containing the obtained conductive composite has excellent conductivity.

When a catalyst and an oxidizing agent are added to the reaction liquid, it is preferable to remove the catalyst and the oxidizing agent from the reaction liquid after the reaction.
Examples of the removal method include a method of contacting the reaction liquid after the reaction with an ion exchange resin to adsorb the catalyst and oxidizing agent on the ion exchange resin, and a method of ultrafiltrating the reaction liquid after the reaction to replace the dispersion medium and remove the catalyst and oxidizing agent. Among these, the method using an ion exchange resin is preferable because it is simple. It is preferable to use a cation exchange resin and an anion exchange resin in combination as the ion exchange resin.

By the above polymerization process, a conductive polymer-containing liquid containing a conductive complex and an aqueous dispersion medium is obtained. Then, the following precipitation and recovery process may be performed.

[Precipitation recovery process]
One or more compounds selected from an epoxy compound, an amine compound, and a quaternary ammonium compound are added to the conductive polymer-containing liquid (hereinafter, sometimes referred to as a conductive polymer dispersion liquid) containing the aqueous dispersion medium obtained in the polymerization step, thereby precipitating a reaction product containing the conductive complex.
The anion groups, such as sulfonic acid groups, of the conductive composite precipitated in this step react with the added compound to form any one of the above-mentioned substituents (A) to (C), thereby making the anion groups hydrophobic.

When one or more epoxy compounds are added to the conductive polymer dispersion, the epoxy groups of the epoxy compounds react with some of the sulfonic acid groups of compound 1 and some of the anion groups of the polyanion. As a result, a substituent (A) is formed and the conductive complex becomes hydrophobic, making it difficult to stably disperse in the aqueous dispersion, and the conductive complex precipitates to form a deposit.
When the epoxy compound is added, heating may be performed to promote the reaction. The heating temperature is preferably 40° C. or higher and 100° C. or lower.
The amount of the epoxy compound added is preferably 10 parts by mass or more and 10,000 parts by mass or less, more preferably 100 parts by mass or more and 5,000 parts by mass or less, and even more preferably 500 parts by mass or more and 3,000 parts by mass or less, relative to 100 parts by mass of the conductive composite.
When the content is at least the lower limit of the above range, the hydrophobicity of the conductive composite is sufficiently high, and the dispersibility in organic solvents, particularly hydrocarbon solvents and ester solvents, is improved.
When the content is equal to or less than the upper limit of the above range, a decrease in electrical conductivity due to unreacted epoxy compound can be prevented.

An organic solvent may be added before, simultaneously with, or after the addition of one or more compounds selected from an epoxy compound, an amine compound, and a quaternary ammonium compound to the conductive polymer dispersion. The organic solvent is preferably a water-soluble organic solvent. Here, the water-soluble organic solvent is an organic solvent that dissolves in an amount of 1 g or more per 100 g of water at a temperature of 20°C. Examples of the water-soluble organic solvent include alcohol-based solvents, ketone-based solvents, and ester-based solvents. One type of organic solvent may be added, or two or more types may be added.

When one or more amine compounds are added to the conductive polymer dispersion, the amine compounds react with some of the sulfonic acid groups of compound 1 and some of the anion groups of the polyanion. As a result, a substituent (B) is formed and the conductive complex becomes hydrophobic, making it difficult to stably disperse in the aqueous dispersion, and the conductive complex precipitates to form a precipitate.
The amount of the amine compound added is preferably 1 part by mass or more and 10,000 parts by mass or less, more preferably 10 parts by mass or more and 5,000 parts by mass or less, and even more preferably 100 parts by mass or more and 1,000 parts by mass or less, relative to 100 parts by mass of the conductive composite.
When the content is at least the lower limit of the above range, the hydrophobicity of the conductive composite is sufficiently high, and the dispersibility in organic solvents, particularly hydrocarbon solvents and ester solvents, is improved.
When the content is equal to or less than the upper limit of the above range, a decrease in electrical conductivity due to unreacted amine compound can be prevented.

When one or more quaternary ammonium compounds are added to the conductive polymer dispersion, the quaternary ammonium compounds react with some of the sulfonic acid groups in compound 1 and some of the anion groups in the polyanion. Substituents (C) are formed and the conductive complex becomes hydrophobic, making it difficult to stably disperse in the aqueous dispersion, and the conductive complex precipitates to form a precipitate.
The amount of the quaternary ammonium compound added is preferably 1 part by mass or more and 10,000 parts by mass or less, more preferably 10 parts by mass or more and 5,000 parts by mass or less, and even more preferably 50 parts by mass or more and 1,000 parts by mass or less, relative to 100 parts by mass of the conductive composite.
When it is at least the lower limit of the above range, the hydrophobicity of the conductive composite is sufficiently high, and the dispersibility in organic solvents is improved.
When the content is equal to or less than the upper limit of the above range, a decrease in electrical conductivity due to unreacted quaternary ammonium compound can be prevented.
The quaternary ammonium compound has a reaction mechanism similar to that of the amine compound, and exhibits good reactivity with the conductive complex even at a smaller amount than the amine compound. The conductivity of the conductive layer containing the conductive complex modified with the quaternary ammonium compound tends to be superior to that of the conductive layer modified with the amine compound.

When both an epoxy compound and an amine compound or a quaternary ammonium compound are added to the conductive polymer dispersion, the order of addition is not particularly limited. Since the synthetic intermediate (reaction intermediate) is easy to handle, it is preferable to first add the epoxy compound and react it, and then add the amine compound or the quaternary ammonium compound and react it.

The method for recovering the precipitated reaction product is not particularly limited, and it can be recovered, for example, by filtration or decantation (solvent replacement method).

The water content of the recovered reaction product (precipitate) is preferably as small as possible, and most preferably contains no water at all, but from a practical standpoint, the water content may be in the range of 10 mass % or less.
Methods for reducing the moisture content include, for example, washing off the precipitate with an organic solvent, drying the precipitate, and the like.

[Cleaning process]
The washing step between the precipitate recovery step and the addition step is a step of washing the precipitate with an organic solvent for washing, which removes residual water, unreacted epoxy compounds, unreacted amine compounds or quaternary ammonium compounds, hydrolyzates of epoxy compounds, and the like.
The organic solvent for cleaning is preferably one that can clean the precipitate while minimizing dissolution of the precipitate. For this reason, the organic solvent for cleaning is preferably an alcohol-based solvent. The organic solvent for cleaning may contain one type of organic solvent or two or more types of organic solvents.
The washing method is not particularly limited, and for example, the precipitate may be washed by pouring an organic washing solvent over the precipitate, or the precipitate may be washed by stirring in the organic washing solvent.

[Addition step]
This step is a step of adding a solvent to the obtained reaction product to obtain a conductive polymer-containing liquid. The solvent to be added may be any solvent that can disperse the reaction product, and it is preferable to use an organic solvent.
The organic solvent may be any of the organic solvents contained in the conductive polymer-containing liquid of the first embodiment. Among them, one or more selected from alcohol-based solvents, ketone-based solvents, and ester-based solvents are preferred, and one or more selected from isopropanol, methyl ethyl ton, and ethyl acetate are more preferred. By using these suitable organic solvents, the dispersibility of the conductive composite contained in the conductive polymer-containing liquid can be further improved.
The content of each solvent contained in the organic solvent is preferably within the preferred range exemplified in the first embodiment.

[Solvent replacement method]
In the precipitation/recovery step and the addition step, the following solvent replacement method may be applied.
The reaction product precipitated in the reaction solution containing the epoxy compound tends to naturally settle to the bottom of the reaction solution. Although the details of the mechanism by which the precipitation occurs have not been elucidated, it is believed that the relationship between the specific gravity of the reaction product and the specific gravity of the reaction solution is an influence.

When the reaction product settles to the bottom layer of the reaction liquid, the upper layer of the reaction liquid contains almost no reaction product. By removing the upper layer by suction, decantation, etc., the concentration of the precipitated reaction product increases, and a residual liquid with a reduced volume is obtained. This operation corresponds to the step of recovering the reaction product.
The resulting residual liquid contains the aqueous dispersion medium derived from the conductive polymer dispersion. Next, an organic solvent is added to the residual liquid to obtain the desired conductive polymer-containing liquid. This operation corresponds to the addition step.
Here, if the amount of the aqueous dispersion medium in the residual liquid is large or the amount of the upper layer removed is small, the reaction product (conductive composite) is not dispersed in the mixed liquid after the organic solvent is added, and can be precipitated again to the lower layer. In this case, by removing the upper layer again, the concentration of the reaction product is increased, the amount of the aqueous dispersion medium is reduced, and a residual liquid with a reduced volume is obtained. By adding the organic solvent to the residual liquid again, a conductive polymer-containing liquid is obtained in which the concentration of the organic solvent is increased (the content of the aqueous dispersion medium is reduced) compared to the first solvent replacement.
This "solvent replacement method" is not limited to being carried out once, but may be repeated two or more times.

By using the solvent replacement method described above, it is possible to obtain a conductive polymer-containing liquid in which the content of the original aqueous dispersion medium is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less, relative to the total mass of the target conductive polymer-containing liquid.

(Distributed Processing)
After the solvent is added to the reaction product, the conductive polymer-containing liquid may be stirred to carry out a dispersion treatment. The stirring method is not particularly limited, and may be a stirring method with a weak shear force such as a stirrer, or may be a stirring method with a dispersing machine with a high shear force such as a high-pressure homogenizer, but it is preferable to use a high-pressure homogenizer from the viewpoint of improving dispersibility.

(Addition of optional ingredients)
A binder component and other additives may be further added to the conductive polymer-containing liquid obtained above. It is preferable that the types and contents of the binder component and additives are within the preferred ranges described in the first embodiment.

<Conductive laminate>
A third aspect of the present invention is a conductive laminate comprising a substrate and a conductive layer formed on at least a portion of the surface of the substrate, the conductive layer being a cured layer of the conductive polymer-containing liquid of the first aspect.

[Conductive layer]
The conductive layer may be formed over the entire surface of any surface of the substrate, or over a portion of the entire surface. In the conductive film, it is preferable that a conductive layer of substantially uniform thickness is formed over substantially the entire surface of one surface or the other surface of the film substrate. When a conductive layer is formed only over a portion of the surface of the substrate, the conductive layer may be, for example, a fine conductive pattern such as a circuit or an electrode, or the conductive layer may be provided on the same surface and the conductive layer may be not provided on the same surface and may be roughly divided.

The average thickness of the conductive layer is, for example, preferably from 10 nm to 100 μm, more preferably from 20 nm to 50 μm, and even more preferably from 30 nm to 30 μm.
When the average thickness of the conductive layer is equal to or greater than the lower limit, high conductivity can be exhibited, and when the average thickness is equal to or less than the upper limit, the adhesion of the conductive layer to the substrate is further improved.
The average thickness of the conductive layer is calculated by measuring the thickness at 10 randomly selected points and averaging the measured values.

[Base material]
The substrate may be a substrate made of an insulating material or a substrate made of a conductive material. The shape of the substrate is not particularly limited, and examples thereof include a shape mainly having a flat surface, such as a film or a substrate.
Examples of insulating materials include glass, synthetic resin, and ceramics.
The conductive material may be a metal, a conductive metal oxide, carbon, or the like.

(Film substrate)
When a film substrate is used as the substrate, the conductive laminate becomes a conductive film.
The film substrate may be, for example, a plastic film made of a synthetic resin, such as ethylene-methyl methacrylate copolymer resin, ethylene-vinyl acetate copolymer resin, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinyl alcohol, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyacrylate, polycarbonate, polyvinylidene fluoride, polyarylate, styrene-based elastomer, polyester-based elastomer, polyethersulfone, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyimide, cellulose triacetate, and cellulose acetate propionate.
From the viewpoint of improving the adhesion between the film substrate and the conductive layer, the synthetic resin for the film substrate is preferably a polyester resin, and among these, polyethylene terephthalate is preferable.

The synthetic resin for the film substrate may be either amorphous or crystalline.
The film substrate may be unstretched or stretched.
The film substrate may be subjected to a surface treatment such as a corona discharge treatment, a plasma treatment, or a flame treatment in order to further improve the adhesion of the conductive layer.

The average thickness of the film substrate is preferably 5 μm to 500 μm, more preferably 20 μm to 200 μm. If the average thickness of the film substrate is equal to or more than the lower limit, the film is less likely to break, and if the average thickness is equal to or less than the upper limit, the film can have sufficient flexibility.
The average thickness of the film substrate is determined by measuring the thickness at 10 randomly selected points and averaging the measured values.

(Glass substrate)
Examples of the glass substrate include an alkali-free glass substrate, a soda-lime glass substrate, a borosilicate glass substrate, and a quartz glass substrate. If the substrate contains an alkali component, the conductivity of the conductive layer tends to decrease, so among the above glass substrates, an alkali-free glass is preferred. Here, the alkali-free glass refers to a glass composition in which the content of the alkali component is 0.1 mass% or less with respect to the total mass of the glass composition.

The average thickness of the glass substrate is preferably from 100 μm to 3000 μm, more preferably from 100 μm to 1000 μm. If the average thickness of the glass substrate is equal to or more than the lower limit, the glass substrate is less likely to break, and if the average thickness is equal to or less than the upper limit, the conductive laminate can be made thinner.
The average thickness of the glass substrate is determined by measuring the thickness at 10 randomly selected points and averaging the measured values.

<Method for manufacturing conductive laminate>
A fourth aspect of the present invention is a method for producing a conductive laminate, the method including applying the conductive polymer-containing liquid of the first aspect to at least a part of a surface of a substrate to form a conductive layer. The conductive laminate of the third aspect can be produced by the production method of this aspect.

Methods for applying the conductive polymer-containing liquid to any surface of a substrate include, for example, methods using a coater such as a gravure coater, roll coater, curtain flow coater, spin coater, bar coater, reverse coater, kiss coater, fountain coater, rod coater, air doctor coater, knife coater, blade coater, cast coater, or screen coater; methods using a sprayer such as an air spray, airless spray, or rotor dampening; and immersion methods such as dipping.

The amount of the conductive polymer-containing liquid to be applied to the substrate is not particularly limited, but in consideration of uniform and even application, conductivity, and film strength, the amount is preferably in the range of 0.01 g/ ^m2 or more and 10.0 g/ ^m2 or less in terms of solid content.

The conductive layer can be formed by drying the coating film made of the conductive polymer-containing liquid applied onto the substrate to remove at least a portion of the dispersion medium and curing the coating film.
Methods for drying the coating film include heat drying, vacuum drying, etc. Examples of heat drying that can be used include hot air heating and infrared heating.
When applying heat drying, the heating temperature is appropriately set depending on the dispersion medium used, but is usually within the range of 50° C. to 200° C. Here, the heating temperature is the set temperature of the drying device. A suitable drying time within the above heating temperature range is preferably 0.5 minutes to 30 minutes, more preferably 1 minute to 15 minutes.

(Production Example 1)
10 g of Duolite C255LFH (Sumika Chemtex Corporation, cation exchange resin) was added to 90 g of Labellin FD-40 (10 wt % aqueous solution, Daiichi Kogyo Seiyaku Co., Ltd., R in formula 1 is a hydrogen atom, weight average molecular weight 13000), which is a salt in which a sodium ion is bound to the sulfonic acid in formula 1, and the mixture was stirred for 16 hours. The resulting solution was filtered to remove the ion exchange resin, and 100 g of a sulfonic acid form of Labellin FD-40 (10 wt % aqueous solution) was obtained.

(Production Example 2)
The same procedure as in Production Example 1 was repeated to obtain 100 g of a sulfonic acid form of Celluflow 120 (10 wt % aqueous solution), except that Labellin FD-40 in Production Example 1 was changed to Celluflow 120 (10 wt % aqueous solution, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., R in Formula 1 is a methyl group, weight average molecular weight 132,000), which is a salt in which a sodium ion is bound to the sulfonic acid in Formula 1.

(Production Example 3)
The procedure of Production Example 1 was repeated, except that Labellin FD-40 in Production Example 1 was changed to Celluflow 110 (10 wt % aqueous solution, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., R in Formula 1 is a hydrogen atom, weight average molecular weight 132,000), which is a salt in which a sodium ion is bonded to the sulfonic acid in the above formula 1, to obtain 100 g of a sulfonate of Celluflow 110 (10 wt % aqueous solution).

(Production Example 4)
The same procedure as in Production Example 1 was repeated, except that Labelin FD-40 was changed to Labelin FC-45M (10 wt % aqueous solution, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., R in Formula 1 is a hydrogen atom, weight average molecular weight 13,000), which is a salt in which a sodium ion is bound to the sulfonic acid in Formula 1, to obtain 100 g of a sulfonate form of Labelin FC-45M (10 wt % aqueous solution).

(Production Example 5)
The procedure of Production Example 1 was repeated, except that Labelin FD-40 was changed to Labelin AN-40 (10 wt % aqueous solution, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., R in Formula 1 is a methyl group, weight average molecular weight 10,000), which is a salt in which a sodium ion is bound to the sulfonic acid in Formula 1, to obtain 100 g of a sulfonate of Labelin AN-40 (10 wt % aqueous solution).

(Production Example 6)
90g of ion-exchanged water and 0.1g of ammonium persulfate were added to 10g of sodium styrenesulfonate and reacted at 80°C for 8 hours. Next, 10g of Duolite C255LFH (cation exchange resin) was added and stirred for 16 hours. The resulting solution was filtered to remove the ion exchange resin, and 100g of polystyrenesulfonic acid (10wt% aqueous solution) was obtained. The weight average molecular weight at this time was 200,000.

Example 1
0.5 g of 3,4-ethylenedioxythiophene, 10 g of the sulfonic acid form of Labellin FD-40 (10 wt % aqueous solution) of Production Example 1, and 89.5 g of ion-exchanged water were added.
The obtained solution was kept at 20° C., and a catalyst solution prepared by dissolving 0.03 g of ferric sulfate in 4.97 g of ion-exchanged water and an oxidant solution prepared by dissolving 1.1 g of ammonium persulfate in 8.9 g of ion-exchanged water were slowly added while stirring, and the obtained reaction solution was stirred for 24 hours to cause a reaction.
By the above reaction, a conductive complex containing poly(3,4-ethylenedioxythiophene) which is a π-conjugated conductive polymer and a sulfonic acid form of Labellin FD-40, water which is a dispersion medium, and a conductive polymer-containing liquid containing the oxidizing agent and catalyst used in the reaction were obtained.
To this conductive polymer-containing liquid, 13.2 g of Duolite C255LFH (a cation exchange resin manufactured by Sumika Chemtex Corporation) and 13.2 g of Duolite A368S (anion exchange resin manufactured by Sumika Chemtex Corporation) were added, and the ion exchange resin was removed by filtration to obtain a conductive polymer-containing liquid from which the oxidizing agent and the catalyst had been removed. The mass and pH of the solid content (non-volatile components) were measured, and the results are shown in Table 1.
Next, the obtained conductive polymer-containing liquid was applied to a PET film (Lumirror T-60, manufactured by Toray Industries, Inc.) using a #4 bar coater, and dried at 120° C. for 1 minute to obtain a conductive film. The surface resistance value of this conductive film was measured, and the results are shown in Table 1.

Example 2
A conductive polymer-containing solution was obtained and a conductive film was produced in the same manner as in Example 1, except that the amounts of the sulfonic acid form (10 wt % aqueous solution) of Labellin FD-40 in Production Example 1 and the ion-exchanged water were changed to 15 g and 84.5 g, respectively.

Example 3
A conductive polymer-containing liquid was obtained and a conductive film was produced in the same manner as in Example 1, except that 10 g of the sulfonic acid form of Labellin FD-40 (10 wt % aqueous solution) in Production Example 1 was changed to 10 g of Celluflow 120 (10 wt % aqueous solution) in Production Example 2.

Example 4
A conductive polymer-containing liquid was obtained and a conductive film was produced in the same manner as in Example 3, except that the amounts of the sulfonic acid form (10 wt % aqueous solution) of Celluflow 120 in Production Example 2 and the ion-exchanged water were changed to 15 g and 84.5 g, respectively.

Example 5
A conductive polymer-containing liquid was obtained and a conductive film was produced in the same manner as in Example 1, except that 10 g of the sulfonic acid form (10 wt % aqueous solution) of Labellin FD-40 in Production Example 1 was changed to 10 g of the sulfonic acid form (10 wt % aqueous solution) of Celluflow 110 in Production Example 3.

(Example 6)
A conductive polymer-containing liquid was obtained and a conductive film was produced in the same manner as in Example 1, except that 10 g of the sulfonate form (10 wt % aqueous solution) of Labellin FD-40 in Production Example 1 was changed to 10 g of the sulfonate form (10 wt % aqueous solution) of Labellin FC-45M in Production Example 4.

(Example 7)
A conductive polymer-containing solution was obtained and a conductive film was produced in the same manner as in Example 1, except that 10 g of the sulfonic acid form (10 wt % aqueous solution) of Labellin FD-40 in Production Example 1 was changed to 10 g of Labellin AN-40 (10 wt % aqueous solution) in Production Example 5.

(Example 8)
A conductive polymer-containing liquid was obtained and a conductive film was produced in the same manner as in Example 1, except that 10 g of the sulfonate form (10 wt % aqueous solution) of Labellin FD-40 in Production Example 1 was changed to 5 g of the sulfonate form (10 wt % aqueous solution) of Celluflow 120 in Production Example 2 and 5 g of polystyrene sulfonic acid (10 wt % aqueous solution) in Production Example 6.

(Comparative Example 1)
An attempt was made to prepare a conductive polymer-containing liquid in the same manner as in Example 1, except that 10 g of the sulfonic acid form (10 wt % aqueous solution) of Labellin FD-40 in Production Example 1 was not added and the amount of ion-exchanged water added was changed from 84.5 g to 94.5 g. However, all of the conductive polymer (PEDOT) precipitated, so the study was discontinued.

(Comparative Example 2)
A conductive polymer-containing liquid was obtained and a conductive film was produced in the same manner as in Example 1, except that 10 g of the sulfonic acid form (10 wt % aqueous solution) of Labellin FD-40 in Production Example 1 was changed to 10 g of polystyrene sulfonic acid (10 wt % aqueous solution) in Production Example 6.

(Example 9) Modification with an amine compound 50 g of isopropanol and 10 g of trioctylamine were added to 100 g of the conductive polymer-containing liquid obtained in Example 3 and stirred for 1 hour, and trioctylamine was reacted with some of the sulfonic acid groups of the conductive complex. As a result, all of the reaction product was precipitated in the upper layer of the reaction liquid. This precipitate was filtered to obtain a powder of the reaction product of the conductive complex and trioctylamine. Isopropanol was added to this powder to make a 500 g mixed liquid, and the mixture was dispersed using a high-pressure homogenizer to obtain 500 g of a conductive polymer-containing liquid. The solid content of this liquid was measured and the results are shown in Table 2.
Next, the obtained conductive polymer-containing liquid was applied onto a PET film using a #8 bar coater and dried at 100° C. for 1 minute to obtain a conductive film.

Example 10
A conductive film was obtained in the same manner as in Example 9, except that 100 g of the conductive polymer-containing liquid obtained in Example 3 was changed to 100 g of the conductive polymer-containing liquid obtained in Example 8.

(Comparative Example 3)
A conductive film was obtained in the same manner as in Example 9, except that 100 g of the conductive polymer-containing liquid obtained in Example 3 was changed to 100 g of the conductive polymer-containing liquid obtained in Comparative Example 2.

(Example 11) Modification with an epoxy compound 25 g of an epoxy compound (Epolite M-1230, C12, 13 mixed higher alcohol glycidyl ether, manufactured by Kyoeisha Chemical Co., Ltd.) was added to 100 g of the conductive polymer-containing liquid obtained in Example 3, and the mixture was heated and stirred at 60°C for 4 hours to react the epoxy compound with some of the sulfonic acid groups of the conductive complex. As a result, a reaction product was precipitated. This precipitate was filtered, and the reaction product of the conductive complex and the epoxy compound was recovered. Methyl ethyl ketone was added to this reaction product to make 300 g of a mixed liquid, and the mixture was dispersed using a high-pressure homogenizer to obtain 300 g of a conductive polymer-containing liquid. The solid content of this liquid was measured, and the results are shown in Table 2.
Next, the obtained conductive polymer-containing liquid was applied onto a PET film using a #8 bar coater and dried at 100° C. for 1 minute to obtain a conductive film.

Example 12
A conductive film was obtained in the same manner as in Example 11, except that 100 g of the conductive polymer-containing liquid obtained in Example 3 was changed to 100 g of the conductive polymer-containing liquid obtained in Example 8.

(Comparative Example 4)
A conductive film was obtained in the same manner as in Example 11, except that 100 g of the conductive polymer-containing liquid obtained in Example 3 was changed to 100 g of the conductive polymer-containing liquid obtained in Comparative Example 2.

(Example 13) Modification with epoxy compound and amine compound 25 g of an epoxy compound (Kyoeisha Chemical Co., Ltd., Epolight M-1230, C12, 13 mixed higher alcohol glycidyl ether) was added to 100 g of the conductive polymer-containing liquid obtained in Example 3, and the mixture was heated and stirred at 60 ° C. for 4 hours. Next, 50 g of isopropanol and 10 g of trioctylamine were added and stirred for 1 hour, whereby the epoxy compound and trioctylamine reacted with some of the sulfonic acid groups of the conductive complex. As a result, a reaction product was precipitated. This precipitate was filtered to obtain a reaction product of the conductive complex with the epoxy compound and trioctylamine. Ethyl acetate was added to this reaction product to obtain 800 g of a mixed liquid, which was then dispersed using a high-pressure homogenizer to obtain 800 g of a conductive polymer-containing liquid. The solid content of this liquid was measured and the results are shown in Table 2.
Next, the obtained conductive polymer-containing liquid was applied onto a PET film using a #8 bar coater and dried at 100° C. for 1 minute to obtain a conductive film.

(Example 14)
A conductive film was obtained in the same manner as in Example 13, except that 100 g of the conductive polymer-containing liquid obtained in Example 3 was changed to 100 g of the conductive polymer-containing liquid obtained in Example 8.

(Comparative Example 5)
A conductive film was obtained in the same manner as in Example 13, except that 100 g of the conductive polymer-containing liquid obtained in Example 3 was changed to 100 g of the conductive polymer-containing liquid obtained in Comparative Example 2.

<Results>
The electrical conductivity of the conductive films of the Examples, which were produced using a conductive polymer-containing liquid containing a conductive complex having Compound 1, was superior to that of the Comparative Examples. Since the Comparative Examples did not contain Compound 1, the electrical conductivity was inferior.

Claims (10)

A conductive polymer-containing liquid comprising a conductive complex containing a π-conjugated conductive polymer and a naphthalenesulfonic acid-based compound represented by the following formula 1, and a dispersion medium:
Formula 1:
RC ₁₀ H ₆ SO ₃ H-(CH ₂ -RC ₁₀ H ₅ SO ₃ H) _n -CH ₂ -RC ₁₀ H ₆ SO ₃ H
[In the formula, each R independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent, and n represents an integer of 1 or more.] The conductive polymer-containing liquid according to claim 1, further comprising a polyanion other than the naphthalene sulfonic acid compound. The conductive polymer-containing liquid according to claim 1 or 2, wherein the naphthalene sulfonic acid compound is modified by reaction with at least one of an epoxy compound, an amine compound, and a quaternary ammonium compound. The conductive polymer-containing liquid according to any one of claims 1 to 3, wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene). The conductive polymer-containing liquid according to claim 2, wherein the polyanion is polystyrene sulfonic acid. A method for producing a conductive polymer-containing liquid, comprising polymerizing a monomer that forms a π-conjugated conductive polymer in a reaction liquid containing a naphthalenesulfonic acid-based compound represented by the following formula 1 and a dispersion medium, thereby obtaining a conductive polymer-containing liquid containing a conductive complex containing the π-conjugated conductive polymer and the naphthalenesulfonic acid-based compound, and a dispersion medium.
Formula 1:
RC ₁₀ H ₆ SO ₃ H-(CH ₂ -RC ₁₀ H ₅ SO ₃ H) _n -CH ₂ -RC ₁₀ H ₆ SO ₃ H
[In the formula, each R independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent, and n represents an integer of 1 or more.] The method for producing a conductive polymer-containing liquid according to claim 6, further comprising the step of: adding a polyanion other than the naphthalenesulfonic acid-based compound to the reaction liquid. The method for producing a conductive polymer-containing liquid according to claim 6 or 7, comprising reacting the conductive complex with at least one of an epoxy compound, an amine compound, and a quaternary ammonium compound to obtain a conductive polymer-containing liquid containing the resulting reaction product and an organic solvent. A method for producing a conductive laminate, comprising applying the conductive polymer-containing liquid according to any one of claims 1 to 5 to at least a portion of the surface of a substrate. A conductive laminate comprising a substrate and a conductive layer formed on at least a portion of the surface of the substrate, the conductive layer being a cured layer of the conductive polymer-containing liquid according to any one of claims 1 to 5.