JP7679291B2 - Conductive polymer-containing liquid and method for producing same, and method for producing conductive laminate - Google Patents

Description

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

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

There is a demand for a further reduction in the surface resistance of a conductive layer formed by curing a coating film of a conventional conductive polymer-containing liquid.
The present invention provides a method for producing a conductive laminate capable of reducing the surface resistance value of a conductive layer by treating a coating film of a conductive polymer-containing liquid under heating and humidifying conditions, as well as a conductive polymer-containing liquid suitable for use in the production method and a production method thereof.

[1] A conductive polymer-containing liquid containing a conductive complex containing a π-conjugated conductive polymer and a polyanion, a binder component, and a conductivity enhancing agent, the conductive polymer-containing liquid being used for the purpose of producing a conductive laminate by carrying out the following steps 1 to 3 in order:
(Step 1)
A step (step 2) of obtaining a conductive laminate A by applying the conductive polymer-containing liquid to at least a part of the surface of a substrate to form a coating film and drying the coating film to form a conductive layer.
A step of obtaining a conductive laminate B by maintaining the conductive laminate A including the substrate and the conductive layer under heated and humidified conditions of 60° C. to 85° C. and 60% RH to 85% RH for 10 days to 30 days (step 3).
[2] A process of obtaining a conductive laminate C by holding the conductive laminate B under non-humidified heating conditions of 60°C or higher and 85°C or lower for 10 days or higher and 30 days or lower, and drying the conductive layer. The conductive polymer-containing liquid according to [1], wherein the surface resistance value B (unit: Ω/□) of the conductive layer of the conductive laminate B is lower than the surface resistance value A (unit: Ω/□) of the conductive layer of the conductive laminate A.
[3] The conductive polymer-containing liquid according to [1] or [2], wherein the surface resistance value C (unit: Ω/□) of the conductive layer of the conductive laminate C is lower than the surface resistance value A (unit: Ω/□) of the conductive layer of the conductive laminate A.
[4] The conductive polymer-containing liquid according to any one of [1] to [3], wherein the surface resistance value B (unit: Ω/□) of the conductive layer of the conductive laminate B is lower than the surface resistance value C (unit: Ω/□) of the conductive layer of the conductive laminate C.
[5] The conductive polymer-containing liquid according to any one of [1] to [4], wherein the conductive agent is one or more selected from the group consisting of a compound having two or more hydroxyl groups, a compound having two or more carboxyl groups, a compound having an amide group, and a nitrogen-containing aromatic compound.
[6] The conductive polymer-containing liquid according to any one of [1] to [5], wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene) or the polyanion is polystyrenesulfonic acid.
[7] The conductive polymer-containing liquid according to any one of [1] to [6], wherein the conductive complex is modified by a reaction with one or more compounds selected from an epoxy compound, an amine compound, and a quaternary ammonium compound.
[8] A method for producing a conductive laminate, comprising using the conductive polymer-containing liquid according to any one of [1] to [7] and sequentially carrying out steps 1 to 3 to obtain the conductive laminate C.
[9] The method for producing a conductive laminate according to [8], wherein the substrate is a film substrate.
[10] A method for producing a conductive polymer-containing liquid according to [7], comprising the steps of: adding one or more compounds selected from an epoxy compound, an amine compound, and a quaternary ammonium compound to a raw material liquid containing a conductive complex containing a π-conjugated conductive polymer and a polyanion, and an aqueous dispersion medium; recovering a reaction product between the added compound and the conductive complex; and mixing the reaction product, a solvent, a binder component, and a highly conductive agent to obtain a conductive polymer-containing liquid.

According to the method for producing a conductive laminate using a conductive polymer-containing liquid of the present invention, a conductive laminate having a conductive layer with a low surface resistance can be produced.
The conductive polymer-containing liquid of the present invention is useful for use in the above-mentioned method for producing a conductive laminate.
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 containing a π-conjugated conductive polymer and a polyanion, a binder component, and a conductivity enhancing agent. The conductive polymer-containing liquid of this aspect is preferably used in a method for producing a conductive laminate described later.
In the conductive polymer-containing liquid of this embodiment, the conductive complex may be in a dispersed state or a dissolved state. In this specification, unless otherwise specified, no distinction is made between the dispersed state and the 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 π-conjugated conductive polymers, poly(3,4-ethylenedioxythiophene) is particularly preferred 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.

<Polyanion>
A polyanion 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 a 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.

A conductive complex is formed by doping a polyanion into a π-conjugated conductive polymer. However, in the polyanion that formed the conductive complex, some anion groups are not doped into the π-conjugated conductive polymer, and there are excess anion groups that are not involved in the doping. Since these excess anion groups are hydrophilic groups, the conductive complex has high water dispersibility and low organic solvent dispersibility.
When the number of all anionic groups in the polyanion forming the conductive complex is taken as 100 mol %, the excess anionic groups are preferably 30 mol % or more and 90 mol % or less, and more preferably 45 mol % or more and 75 mol % or less.

The content of the polyanion in the conductive complex is preferably in the range of 1 part by mass to 1000 parts by mass, more preferably 10 parts by mass to 700 parts by mass, and even more preferably 100 parts by mass to 500 parts by mass, per 100 parts by mass of the π-conjugated conductive polymer. If the content of the polyanion is equal to or greater than the lower limit, the doping effect on the π-conjugated conductive polymer tends to be stronger, and the conductivity becomes higher. On the other hand, if the content of the polyanion is equal to or less than the upper limit, the π-conjugated conductive polymer can be sufficiently contained, so that sufficient conductivity can be ensured.

The content of the conductive complex relative to the total mass of the conductive polymer-containing liquid of this embodiment can be, for example, 0.01 mass % or more and 10.0 mass % or less, preferably 0.05 mass % or more and 5.0 mass % or less, more preferably 0.1 mass % or more and 2.0 mass % or less, and even more preferably 0.5 mass % or more and 1.0 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 to be formed becomes higher.
When it 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.

The content of the π-conjugated conductive polymer relative to the total mass of the conductive polymer-containing liquid of this embodiment can be, for example, from 0.01% by mass to 2.0% by mass.
The content of the polyanion relative to the total mass of the conductive polymer-containing liquid of this embodiment can be, for example, 0.03 mass % or more and 10 mass % or less.
The content ratio of the π-conjugated conductive polymer to the polyanion contained in the conductive polymer-containing liquid of this embodiment is preferably (1:2) to (1:5) on a mass basis, more preferably (1:2) to (1:4), and even more preferably (1:2) to (1:3).

The conductive complex contained in the conductive polymer-containing liquid of this embodiment may be modified by reaction with one or more compounds selected from an epoxy compound, an amine compound, and a quaternary ammonium compound. At least a portion of the excess anion groups not involved in doping the polyanion contained in the conductive complex are modified by the above reaction to form any of the substituents (A) to (C) described below. The conductive complex having the substituents (A) to (C) has increased hydrophobicity and improved dispersibility in organic solvents.

<Binder Components>
The conductive polymer-containing liquid of this embodiment contains a binder component. By containing the binder component, the strength of the conductive layer to be formed is improved, and the conductive layer can be sufficiently withstood, in particular, a stationary treatment under heating and humidifying conditions to be described later, and a subsequent drying treatment under heating and non-humidifying conditions.

The binder component is a resin or a precursor thereof other than the π-conjugated conductive polymer 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 one type only, or two or more types may be included.

Specific examples of binder resins derived from binder components include epoxy resins, acrylic resins, polyester resins, polyurethane resins, polyimide resins, polyether resins, melamine resins, and silicones.

When the conductive polymer-containing liquid of this embodiment contains an aqueous dispersion medium, the binder resin is preferably a water-dispersible resin, and more preferably a water-dispersible emulsion resin. The water-dispersible resin is an emulsion resin or a water-soluble resin.

Specific examples of water-dispersible emulsion resins include acrylic resins, polyester resins, polyurethane resins, polyimide resins, melamine resins, etc., which are made into emulsions using an emulsifier.

Since the strength of the coating film formed by applying the conductive polymer-containing liquid of this embodiment to a substrate is increased, the binder resin preferably contains a resin having an epoxy group, more preferably contains an acrylic resin having an epoxy group, and even more preferably contains an emulsion of an acrylic resin having an epoxy group.

In order to increase the strength of the coating film formed by coating the conductive polymer-containing liquid of this embodiment on a substrate, the binder resin preferably contains a polyester resin, more preferably contains an emulsion of a polyester resin. In particular, when the binder resin is applied to a polyester film substrate, the binder resin preferably contains a polyester resin or an emulsion thereof, since the adhesiveness of the coating film to the substrate is increased.
The combined use of the above acrylic resin and polyester resin is preferred since it further increases the strength and adhesion of the coating film.

Specific examples of the water-soluble resin include acrylic resin, polyester resin, polyurethane resin, polyimide resin, and melamine resin, which have an acid group such as a carboxy group or a sulfo group or a salt thereof. Here, the water-soluble resin is preferably one that dissolves in an amount of 1 g or more, preferably 5 g or more, and more preferably 10 g or more in 100 g of distilled water at 25° C.
The acid group, such as a carboxy group or a sulfo group, contained in the water-dispersible resin may form a salt with a cation, such as a sodium ion or a potassium ion.

When the conductive polymer-containing liquid of this embodiment contains a sufficient amount of organic solvent, it can contain a binder component that has low solubility in water.

The binder component may be a curable monomer or oligomer, which may be a thermosetting monomer or oligomer, or may be 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 organosiloxane or silicone oligomer is used as the binder component, releasability (non-adhesiveness) can be imparted to the conductive layer.

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. In addition, when an organosiloxane or silicone oligomer is included, it is preferable to include a platinum catalyst for curing.

The content ratio of the binder component contained in the conductive polymer-containing liquid of this embodiment is preferably 100 parts by mass or more and 20,000 parts by mass or less, more preferably 500 parts by mass or more and 10,000 parts by mass or less, and even more preferably 1,000 parts by mass or more and 5,000 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, the film formability and film strength can be improved when the conductive polymer-containing liquid of this embodiment is applied to a substrate.
When the content is equal to or less than the upper limit of the above range, a decrease in electrical conductivity due to a decrease in the content ratio of the conductive complex can be suppressed.

<Highly conductive agent>
The conductive polymer-containing liquid of this embodiment contains a highly conductive agent. By containing the highly conductive agent, the conductivity of the conductive layer to be formed can be improved, and in particular, the conductivity can be remarkably improved by a static treatment under heating and humidifying conditions described later.
Here, the above-mentioned π-conjugated conductive polymers, polyanions, binder resins, and organic solvents are not classified as high-conductivity agents.

The conductive agent is preferably at least one compound selected from the group consisting of saccharides, compounds having two or more hydroxy groups, compounds having two or more carboxy groups, compounds having one or more hydroxy groups and one or more carboxy groups, compounds having an amide group, compounds having an imide group, nitrogen-containing aromatic compounds, lactam compounds, and compounds having a glycidyl group, where a distinction is made between hydroxy groups and carboxy groups.
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.

Examples of compounds having two or more hydroxyl groups (polyhydric alcohols) include thiodiglycol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,4-tetramethylene diol, 1,3-tetramethylene diol, 2-methyl-1,3-trimethylene diol, 1,5-pentamethylene diol, neopentyl glycol, 1,6-hexamethylene diol, 3-methyl-1,5-pentamethylene diol, 2,4-diethyl-1,5-pentamethylene diol, glycerin, trimethylolpropane, trimethylolethane, cyclohexanediols (such as 1,4-cyclohexanediol), bisphenols (such as bisphenol A), sugar alcohols (such as xylitol and sorbitol), gallic acid, and gallic acid alkyl esters.

Examples of compounds having two or more carboxy groups (polycarboxylic acids) include aliphatic dicarboxylic acids such as malonic acid, maleic acid, fumaric acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, paraphenylenedicarboxylic acid, and trimellitic acid, and sulfur-containing carboxylic acids such as thiodipropionic acid.

A compound having an amide group (amide compound) is a monomolecular compound that has an amide bond represented by -CO-NH- (the CO part is a double bond) in the molecule. Specific examples include acetamide, malonamide, succinamide, maleamide, fumaramide, benzamide, naphthamide, phthalamide, isophthalamide, terephthalamide, nicotinamide, isonicotinamide, 2-furamide, formamide, N-methylformamide, propionamide, propiolamide, butyramide, isobutyramide, palmitamide, stearylamide, oleamide, oxamide, glutaramide, adipamide, cinnamamide, glycolamide, lactamide, glyceramide, tartaramide, citramide, glyoxylamide, pyruvamide, acetoacetamide, dimethylacetamide, benzylamide, anthranilamide, ethylenediaminetetraacet ... Examples of acrylamides include triacetamide, diacetamide, triacetamide, dibenzamide, tribenzamide, rhodanine, urea, 1-acetyl-2-thiourea, biuret, butylurea, dibutylurea, 1,3-dimethylurea, 1,3-diethylurea and derivatives thereof, N-methylacrylamide, N-methylmethacrylamide, N-ethylacrylamide, N-ethylmethacrylamide, N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, 2-hydroxyethylacrylamide, 2-hydroxyethylmethacrylamide, N-methylolacrylamide, and N-methylolmethacrylamide.

Examples of nitrogen-containing aromatic compounds (aromatic compounds in which at least one nitrogen atom forms a ring structure) include pyrrole, indole, imidazole, 2-methylimidazole, 2-propylimidazole, N-methylimidazole, N-propylimidazole, N-butylimidazole, 1-(2-hydroxyethyl)imidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, These include derivatives such as imidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 1-acetylimidazole, 2-aminobenzimidazole, 2-amino-1-methylbenzimidazole, 2-hydroxybenzimidazole, 2-(2-pyridyl)benzimidazole, pyridine, pyrimidine, pyrazine, and their alkyl-substituted derivatives (e.g., those substituted with an alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, propyl, or butyl), halogen-substituted derivatives (e.g., those substituted with a halogen group such as fluoro, chloro, or bromine), and nitrile-substituted derivatives.

The content of the conductive agent in the conductive polymer-containing liquid of this embodiment is preferably 0.001% by mass or more and 10% by mass or less, more preferably 0.01% by mass or more and 1.0% by mass or less, and even more preferably 0.02% by mass or more and 0.2% by mass or less, relative to the total mass of the conductive polymer-containing liquid.
When the content is within the above preferred range, the effect of improving the electrical conductivity by adding the highly conductive agent can be further enhanced.

The content ratio of the conductive agent 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 30 parts by mass or more and 1,000 parts by mass or less, and even more preferably 50 parts by mass or more and 2,000 parts by mass or less, relative to 100 parts by mass of the conductive composite.
When the content is within the above preferred range, the effect of improving the electrical conductivity by adding the highly conductive agent can be further enhanced.

[Dispersion medium]
The conductive polymer-containing liquid of this embodiment preferably contains a dispersion medium because it is easy to disperse the conductive complex in the liquid. Examples of the dispersion medium include water, an organic solvent, and a mixture of water and an organic solvent. The conductive agent is not considered to be a dispersion medium.

Examples of the organic solvent include alcohol-based solvents, ether-based solvents, ketone-based solvents, ester-based solvents, aromatic hydrocarbon-based solvents, etc. Specific examples will be described later.
The organic solvents may be used alone or in combination of two or more kinds.

Since the unmodified conductive composite has high dispersibility in water, the dispersion medium for the unmodified conductive composite is preferably an aqueous dispersion medium containing water.
The content ratio of water to the total mass of the aqueous dispersion medium contained in the conductive polymer-containing liquid of this embodiment can be, for example, 50% by mass or more and 100% by mass or less, preferably 60% by mass or more and 100% by mass or less, and more preferably 70% by mass or more and 100% by mass or less. As the dispersion medium other than water, a monohydric alcohol is preferable.
Since the modified conductive complex having the substituents (A) to (C) described below has increased hydrophobicity, the dispersion medium for the modified conductive complex is preferably an organic solvent.

(Other additives)
The conductive polymer-containing liquid of this embodiment may contain other 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 additive, the content ratio thereof is appropriately determined depending on the type of additive, and can be, for example, in the range of 0.001 parts by mass or more and 5 parts by mass or less relative to 100 parts by mass of the π-conjugated conductive polymer and the total polyanion.

<<Method for producing conductive polymer-containing liquid (1)>>
The conductive polymer-containing liquid of the first embodiment can be produced, for example, by a production method including a polymerization step described below.
The polymerization step is a step of obtaining a conductive polymer-containing liquid containing a conductive complex containing the π-conjugated conductive polymer and the polyanion, and the aqueous dispersion medium by polymerizing a monomer that forms a π-conjugated conductive polymer in a reaction liquid containing a polyanion and an aqueous dispersion medium. The conductive polymer-containing liquid of the first embodiment is obtained by adding a binder component and a highly conductive agent to the conductive polymer-containing liquid obtained in the polymerization step.

The weight average molecular weight (Mw) of the polyanion to be subjected to the polymerization step is preferably from 80,000 to 1,000,000, more preferably from 100,000 to 800,000, and even more preferably from 150,000 to 600,000. Here, the weight average molecular weight is the average molecular weight on a mass basis measured by gel permeation chromatography (GPC) using pullulan of a known weight average molecular weight as a standard substance.
When the weight average molecular weight is in the above preferred range, the conductivity of the conductive layer is further increased.
Before subjecting the aqueous solution of the polyanion to GPC, it is preferable to filter the aqueous solution through a membrane filter having an average pore size of 0.2 μm in order to remove impurities contained in the aqueous solution, and then subject the filtrate to GPC measurement.

One method for synthesizing a polyanion with a specific weight-average molecular weight is, for example, to adjust the amount of oxidizing agent added to polymerize the monomers that make up the polyanion. Specifically, by increasing the concentration of the oxidizing agent, the weight-average molecular weight of the polyanion formed by polymerization of the monomers can be reduced. By this method, for example, polystyrene sulfonic acid with a weight-average molecular weight Mw of 100,000 or more and 1,000,000 or less can be obtained.

[Polymerization process]
A reaction solution containing a monomer forming the π-conjugated conductive polymer and the polyanion at an arbitrary content ratio is prepared, and the monomer is polymerized to form a π-conjugated conductive polymer. In the reaction solution, the polyanion naturally dopes the π-conjugated conductive polymer, forming a conductive complex consisting of the π-conjugated conductive polymer and the polyanion.

A catalyst may be added to the reaction solution. The catalyst is not particularly limited as long as it promotes the polymerization of the monomers, and examples of the catalyst include transition metal compounds such as ferric chloride, ferric sulfate, ferric nitrate, and cupric chloride. Among them, it is preferable to use a catalyst containing iron, since the polymerization of the monomers proceeds stably at room temperature.

The reaction liquid preferably contains an oxidizing agent together with the catalyst. The oxidizing agent is capable of polymerizing the monomer. Examples of the oxidizing agent include persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate.
It is preferable that the oxidizing agent is dissolved in ion-exchanged water in advance as an oxidizing agent solution, and the oxidizing agent solution is slowly added to the mixed liquid S1 containing the monomer, the polyanion, and the catalyst to initiate polymerization.
The concentration of the oxidizing agent solution is preferably 1.0% by mass or more and 3.0% by mass or less.

The reaction time required to complete the reaction is approximately 4 to 12 hours, and preferably 6 to 10 hours. The end of the polymerization reaction can be determined by confirming by gas chromatography that the monomers that form the π-conjugated conductive polymer have disappeared.

The content ratio of the monomer to the polyanion contained in the mixed solution S1 is preferably from (1:2) to (1:5) on a mass basis, more preferably from (1:2) to (1:4), and even more preferably from (1:2) to (1:3).
When the content is at least the lower limit of the above range, the doping effect of the polyanion is sufficiently exhibited, and the dispersion stability of the conductive composite is further improved.
When the content is equal to or less than the upper limit of the above range, a conductive polymer-containing liquid capable of forming a conductive layer having excellent conductivity can be easily obtained.

The content of the monomer relative to the total mass of the mixed liquid S1 is, for example, preferably 0.1 mass % or more and 10 mass % or less, more preferably 0.2 mass % or more and 5.0 mass % or less, and even more preferably 0.3 mass % or more and 1.0 mass % or less.
When the amount is within the above range, the polymerization reaction can proceed stably, and therefore complexation with the polyanion present in the reaction system proceeds easily.

The content of the polyanion relative to the total mass of the mixed solution S1 is preferably set based on the content ratio relative to the monomer. For example, it is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.3% by mass or more and 8.0% by mass or less, and even more preferably 0.6% by mass or more and 4.0% by mass or less.

(Catalyst and Oxidant Removal)
When a reaction liquid to which a catalyst and an oxidizing agent have been added is used, it is preferable to remove the catalyst and the oxidizing agent from the conductive polymer-containing liquid obtained after the reaction.
Examples of the removal method include a method of contacting a conductive polymer-containing liquid with an ion exchange resin to adsorb the catalyst and oxidizing agent to the ion exchange resin, and a method of ultrafiltrating the conductive polymer-containing liquid to replace the aqueous 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.

(Distributed Processing)
The conductive polymer-containing liquid obtained in the polymerization step may be stirred to disperse the conductive composite. The stirring method is not particularly limited, and may be a stirrer or the like that exerts a weak shear force, or may be a high-shear homogenizer or other dispersing device that exerts a high shear force, but it is preferable to use a high-pressure homogenizer or the like in order to improve dispersibility.

By the above polymerization process, a conductive polymer-containing liquid is obtained, which contains a conductive complex containing a π-conjugated conductive polymer and a polyanion, and the aqueous dispersion medium.
Furthermore, a binder component and a highly conductive agent are added and mixed in a conventional manner to obtain the desired conductive polymer-containing liquid.

<<Method for producing conductive polymer-containing liquid (2)>>
A second aspect of the present invention is a method for producing a conductive polymer-containing liquid, the method including: a step (reaction step) of adding one or more compounds selected from an epoxy compound, an amine compound, and a quaternary ammonium compound to a raw material liquid containing a conductive complex containing a π-conjugated conductive polymer and a polyanion, and an aqueous dispersion medium; a step (recovery step) of recovering a reaction product between the added compound and the conductive complex; and a step (mixing step) of obtaining a conductive polymer-containing liquid by mixing the reaction product, a solvent, a binder component, and a highly conductive agent.

[Reaction step]
As the raw material liquid, the conductive polymer-containing liquid (hereinafter, sometimes referred to as conductive polymer dispersion liquid) obtained by the above-mentioned production method (1) can be used.
By adding one or more compounds selected from an epoxy compound, an amine compound, and a quaternary ammonium compound to the conductive polymer dispersion, a reaction product containing the conductive complex can be precipitated.
The anion groups such as sulfonic acid groups of the reaction product precipitated in this step react with the added compound to form any one of the following substituents (A) to (C) and are hydrophobized.

The excess anionic groups of the polyanion that are not involved in the dope are hereinafter sometimes referred to as "a portion of the anionic groups".
A portion of the anion group reacts with the epoxy compound to form the following substituent (A).
A part of the anion group reacts with the amine compound to form the following substituent (B).
The following substituent (C) is formed by the reaction of a portion of the anionic group with a quaternary ammonium compound.

(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 indicates that the substituent (A) is substituted with a proton of an anion group such as a 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 part of the anionic groups 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, p-toluenesulfonate glycidyl, 3-methyl-3-phenylglycidic acid ethyl, N-propyl-N-(2,3-epoxypropyl)perfluoro-n-octylsulfonamide, (2S,3S)-1,2-epoxy-3-(tert-butoxycarbonylamino)-4-phenylbutane, 3-nitrobenzenesulfonate (R)-glycidyl, 3-nitrobenzenesulfonate-glycidyl, parthenolide, N-glycidylphthalimide, endrin, dieldrin, 4-glycidyloxycarbazole, 7,7-dimethyloctanoate [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 a negative charge of an anion group, for example, a negative charge of a sulfonic acid group "-SO ₃ ^- ", and a positive charge of an 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 part of the anion groups 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 contained in R ¹¹ to R ¹³ 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 part of the anion groups 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 reaction product A obtained by reacting an epoxy compound) - (conductive composite before reacting with an epoxy compound)]. The mass of [substituent (B)] can be calculated by [(mass of reaction product B obtained by reacting the reaction product A with an amine compound) - (mass of the reaction product 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 a negative charge of an anion group, for example, a negative charge of a sulfonic acid group "-SO ₃ ^- ", and a positive charge of a quaternary ammonium cation.

In the chemical formula (C), R ¹¹ to R ¹⁴ are a hydrocarbon group which may have a substituent. In the 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 reaction product A obtained by reacting with an epoxy compound) - (conductive complex before reacting with an epoxy compound)]. The mass of [substituent (C)] can be calculated by [(mass of reaction product C obtained by reacting the reaction product A with a quaternary ammonium compound) - (mass of the reaction product A)].

When one or more kinds of epoxy compounds are added to the conductive polymer dispersion, the amount of the epoxy compounds 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 π-conjugated conductive polymer and all polyanions contained in the conductive polymer dispersion.
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 epoxy compound can be prevented.
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.

When one or more kinds of amine compounds are added to the conductive polymer dispersion, 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 2,000 parts by mass or less, relative to 100 parts by mass of the π-conjugated conductive polymer and all polyanions contained in the conductive polymer dispersion.
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 amine compound can be prevented.

When one or more kinds of quaternary ammonium compounds are added to the conductive polymer dispersion, 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 2,000 parts by mass or less, relative to 100 parts by mass of the π-conjugated conductive polymer and all polyanions contained in the conductive polymer dispersion.
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 even with a smaller amount of addition than the amine compound. The conductivity of the conductive layer containing the conductive complex modified with the quaternary ammonium compound tends to be better than that of the conductive layer modified with the amine compound.

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. 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 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.

[Recovery process]
The method for recovering the precipitated reaction product is not particularly limited, and the product can be recovered, for example, by filtration, decantation, or the like.

The recovered reaction product preferably contains as little water as possible, and most preferably contains no water at all. From a practical standpoint, however, the reaction product may contain water in the range of 10% by mass or less.
Methods for reducing the water content include, for example, washing the reaction product with an organic solvent, drying the reaction product, and the like.

[Cleaning process]
The method may include a washing step of washing the reaction product recovered in the recovery step, 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 reaction product while minimizing dissolution of the reaction product. 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. For example, the reaction product may be washed by pouring an organic solvent for washing over the reaction product, or the reaction product may be washed by stirring in the organic solvent for washing.

[Mixing process]
The solvent (dispersion medium) in which the reaction product is dispersed preferably contains an organic solvent.
When the conductive polymer-containing liquid contains a hydrophobized conductive complex, the content of the organic solvent relative to the total mass of the solvent is preferably 70 mass % or more and 100 mass % or less, more preferably 80 mass % or more and 100 mass % or less, and even more preferably 90 mass % or more and 100 mass % or less.

The content of the reaction product relative to the total mass of the conductive polymer-containing liquid obtained in this step can be, for example, 0.01 mass % or more and 10.0 mass % or less, preferably 0.05 mass % or more and 5.0 mass % or less, more preferably 0.1 mass % or more and 2.0 mass % or less, and even more preferably 0.5 mass % or more and 1.0 mass % or less.
When the content is at least 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 reaction product in the conductive polymer-containing liquid can be improved, and a uniform conductive layer can be formed.

<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.
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-based 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 contain 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.

Among the above, the organic solvent is preferably one or more selected from alcohol-based solvents, ketone-based solvents, and ester-based solvents, and more preferably one or more selected from isopropanol, methyl ethyl tonne, and ethyl acetate. By using these suitable organic solvents, the dispersibility of the conductive complex contained in the conductive polymer-containing liquid can be further improved.

(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.

By the above method, a conductive polymer-containing liquid containing a conductive complex containing a π-conjugated conductive polymer and a polyanion, and the aqueous dispersion medium can be obtained.
Furthermore, a binder component and a highly conductive agent are added and mixed in a conventional manner to obtain the desired conductive polymer-containing liquid.

<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.
The conductive laminate of this embodiment can be produced by the production method of the fourth embodiment described below.

[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 either 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 glass substrates, an alkali-free glass is preferred. Here, the alkali-free glass refers to a glass composition having an alkali component content of 0.1 mass% or less relative 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 by using the conductive polymer-containing liquid of the first aspect and carrying out the following steps 1 to 3 in order.

(Step 1)
This step is a step of obtaining a conductive laminate A by applying the conductive polymer-containing liquid to at least a partial surface of a substrate to form a coating film, and drying the coating film to form a conductive layer.

The description of the substrate is the same as above, so we will omit the duplicated description here.

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 and the electrical 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 thickness of the coating film immediately after applying the conductive polymer-containing liquid to the substrate is, for example, preferably 0.1 μm to 500 μm, more preferably 1 μm to 100 μm, and even more preferably 5 μm to 50 μm.
The thickness of the coating film can be adjusted, for example, by changing the size of a bar coater.

The conductive layer can be formed by drying the coating film of the conductive polymer-containing liquid applied to the substrate, removing 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 heat drying is applied, 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.
After drying, UV irradiation may be performed to cure the binder component contained in the coating film.

By drying the coating, a conductive laminate A is obtained in which a conductive layer is formed on any surface of the substrate.
The average thickness of the conductive layer in the conductive laminate A is, for example, preferably 10 nm or more and 100 μm or less, more preferably 20 nm or more and 50 μm or less, and even more preferably 30 nm or more and 30 μm or less.
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.

The surface resistance value A of the conductive laminate A can be, for example, 1.0×10 ⁶ Ω/□ or more and 10.0×10 ¹⁰ Ω/□ or less.

(Step 2)
This process is a process for obtaining a conductive laminate B by maintaining the conductive laminate A obtained in the previous process under heated and humidified conditions of 60°C or higher and 85°C or lower and 60% RH or higher and 85% RH or lower for 10 days or longer and 30 days or shorter.
The heating temperature range is preferably from 60°C to 85°C, more preferably from 70°C to 85°C, and even more preferably from 75°C to 85°C.
The range of relative humidity during heating is preferably 60% RH or more and 85% RH or less, more preferably 70% RH or more and 85% RH or less, and even more preferably 75% RH or more and 85% RH or less.
The period during which the conductive laminate A is placed under the above-mentioned heating and humidifying conditions and the conductive layer is kept exposed to the humidity in the atmosphere is preferably from 10 to 30 days, more preferably from 10 to 20 days, and even more preferably from 10 to 15 days. Here, one day means 24 hours.

By exposing the conductive layer to humidity under the above heating and humidifying conditions, the conductivity of the conductive layer can be significantly improved. Although the details of this mechanism are not yet clear, it is speculated that the conductive layer absorbs a small amount of moisture, and heating enhances the molecular motion of the components contained in the conductive complex, etc., improving the conformation and relative arrangement of the molecules in the conductive layer, resulting in increased conductivity.

A specific method for subjecting conductive laminate A to the above heating and humidifying conditions to obtain conductive laminate B is, for example, a method using a commercially available thermo-hygrostat equipped with a sample chamber capable of controlling temperature and humidity. The heating temperature and humidity during the above-mentioned holding of the conductive laminate can be controlled as the set temperature and humidity of the sample chamber.

The surface resistance value B of the conductive laminate B is not particularly limited as long as it is lower than the surface resistance value A, and can be, for example, 1.0×10 ³ Ω/□ or more and 10.0×10 ⁸ Ω/□ or less.

The ratio represented by surface resistance value A/surface resistance value B can be, for example, in the range of 3 to 10,000, in the range of 10 to 5,000, in the range of 20 to 1,000, or in the range of 30 to 100.

(Step 3)
In this process, the conductive laminate B obtained in the previous process is maintained under non-humidified heating conditions of 60°C or higher and 85°C or lower for 10 days or longer and 30 days or shorter to dry the conductive layer, thereby obtaining a conductive laminate C.
The heating temperature range is preferably from 60°C to 85°C, more preferably from 70°C to 85°C, and even more preferably from 80°C to 85°C.
In this step, the above heat treatment is performed without humidification. The humidity at 25° C. in the environment in which this step is performed is preferably, for example, 50% RH or more and 65% RH or less.
The period during which the conductive laminate B is placed under the above non-humidified heating conditions and the conductive layer is kept exposed to the temperature of the atmosphere is preferably from 10 to 30 days, more preferably from 10 to 20 days, and even more preferably from 10 to 15 days. Here, one day means 24 hours.

By drying the conductive layer under the above non-humidified heating conditions, the conductive layer can be kept in an improved state of conductivity. Although the details of this mechanism are not yet clear, it is speculated that by drying and removing the moisture absorbed by the conductive layer in step 2 in this step, the conductive layer formed in step 2 is dried, hardened, and fixed in a state that maintains as much as possible the preferred conformation and relative arrangement of the molecules in the conductive layer formed in step 2, resulting in the conductivity being maintained in a high state.

A specific method for placing the conductive laminate B under the above-mentioned non-humidified heating conditions to obtain the conductive laminate C is, for example, to use a commercially available incubator equipped with a temperature-controllable sample chamber. The heating temperature during the above-mentioned holding of the conductive laminate can be controlled as the set temperature of the sample chamber.

The surface resistance value C of the conductive laminate C is not particularly limited as long as it is lower than the surface resistance value A, but can be, for example, 1.0×10 ⁴ Ω/□ or more and 10.0×10 ⁸ Ω/□ or less.

The ratio represented by surface resistance value A/surface resistance value C can be, for example, in the range of 3 to 10,000, in the range of 10 to 5,000, in the range of 20 to 1,000, or in the range of 30 to 100.

The surface resistance value C tends to be higher than the surface resistance value B. Although the details of this mechanism are not yet clear, it is presumed that the surface resistance value B has high conductivity because the conductive layer contains moisture.
The ratio represented by surface resistance value C/surface resistance value B may be, for example, in the range of 1.1 or more and 100 or less, in the range of 1.2 or more and 50 or less, in the range of 1.3 or more and 20 or less, or in the range of 1.4 or more and 10 or less.

(Production Example 1) Production of polystyrene sulfonic acid 206 g of sodium styrene sulfonate was dissolved in 1000 ml of ion-exchanged water, and while stirring at 80° C., 1.14 g of an oxidizing agent solution of ammonium persulfate previously dissolved in 10 ml of water was added dropwise over 20 minutes, and the solution was stirred for 12 hours.
1000ml of sulfuric acid diluted to 10% by mass was added to the obtained sodium polystyrene sulfonate solution, and about 1000ml of the solvent was removed from the obtained polystyrene sulfonic acid solution by ultrafiltration. Next, 2000ml of ion-exchanged water was added to the remaining liquid, and about 2000ml of the solvent was removed by ultrafiltration to wash the polystyrene sulfonic acid with water. This water washing operation was repeated three times.
Water in the resulting solution was removed under reduced pressure to obtain colorless solid polystyrene sulfonic acid.

(Production Example 2) Synthesis of PEDOT-PSS A solution obtained by dissolving 0.5 g of 3,4-ethylenedioxythiophene and 1.5 g of polystyrene sulfonic acid in 15.0 g of ion-exchanged water was mixed at 20° C. Next, 89.5 g of ion-exchanged water was added.
The resulting mixed solution was kept at 20° C., and while stirring, a solution of 0.03 g of ferric sulfate dissolved in 4.97 g of ion-exchanged water and a solution of 1.1 g of ammonium persulfate dissolved in 8.9 g of ion-exchanged water were slowly added, and the resulting reaction solution was stirred for 24 hours to cause a reaction.
By the above reaction, a conductive polymer-containing liquid was obtained that contained a conductive complex (PEDOT-PSS) containing poly(3,4-ethylenedioxythiophene) and polystyrenesulfonic acid, which are π-conjugated conductive polymers, and water, which is a dispersion medium.
To this conductive polymer-containing liquid, 13.2 g of Duolite C255LFH (Sumika Chemtex Corporation, cation exchange resin) and 13.2 g of Duolite A368S (Sumika Chemtex Corporation, anion exchange resin) 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 solid content (non-volatile components) of the obtained conductive polymer-containing liquid was 1.3 mass%.

(Production Example 3) Reaction 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 Production Example 2 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 floated in the upper layer of the reaction liquid. This reaction liquid 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 (solid content 0.6% by mass).

(Production Example 4) Reaction 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 Production Example 2, 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 (solid content 0.5% by mass).

(Production Example 5) Reaction 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 Production Example 2, 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 (solid content 0.3% by mass).

Example 1
40 g of PLASCOAT RZ105 (manufactured by GOO Chemical Co., Ltd., water-dispersed polyester, solid content 25% by mass) and 0.25 g of methyl gallate were added to 60 g of the conductive polymer-containing liquid obtained in Production Example 2. 900 g of methanol was further added to this solution, and the resulting conductive polymer-containing liquid was applied to a PET film using a #4 bar coater and dried at 120° C. for 1 minute to obtain a conductive film. The surface resistance value A of this conductive film was measured, and the results are shown in Table 1.
Next, the conductive film after measuring the surface resistance value A was left to stand for 10 days under humidified conditions of a temperature of 85° C. and a humidity of 85% RH, and then the surface resistance value B was measured in the same manner as above.
Furthermore, the conductive film after measuring the surface resistance value B was left to stand for 10 days under non-humidified conditions at 85° C., and then the surface resistance value C was measured in the same manner as above.
The measured surface resistance values (unit: Ω/□) are shown in Table 1.

The surface resistance value of the conductive layer of the conductive film was measured using a resistivity meter (Hiresta manufactured by Nitto Seiko Analytech Co., Ltd.) under the condition of an applied voltage of 10 V. In the table, "1.0E+05" means "1.0×10 ⁵ ," and the same applies to the other values.

Example 2
A conductive polymer-containing liquid was obtained, a conductive film was produced, and each surface resistance value was measured in the same manner as in Example 1, except that the amount of methyl gallate added in Example 1 was changed to 0.5 g.

Example 3
A conductive polymer-containing liquid was obtained, a conductive film was produced, and each surface resistance value was measured in the same manner as in Example 1, except that the amount of methyl gallate added in Example 1 was changed to 1.0 g.

Example 4
A conductive polymer-containing liquid was obtained, a conductive film was produced, and each surface resistance value was measured in the same manner as in Example 1, except that the amount of methyl gallate added was changed to 2.0 g.

Example 5
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 1.0 g of thiodipropionic acid was added instead of 0.25 g of methyl gallate in Example 1, and a conductive film was produced and each surface resistance value was measured.

Example 6
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 1.0 g of imidazole was added instead of 0.25 g of methyl gallate in Example 1, and a conductive film was produced and each surface resistance value was measured.

(Example 7)
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 1.0 g of thiodiglycol was added instead of 0.25 g of methyl gallate in Example 1, and a conductive film was produced and each surface resistance value was measured.

(Example 8)
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 1.0 g of sorbitol was added instead of 0.25 g of methyl gallate in Example 1, and a conductive film was produced and each surface resistance value was measured.

(Example 9)
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 1.0 g of hydroxyethylacrylamide was added instead of 0.25 g of methyl gallate in Example 1, and a conductive film was produced and each surface resistance value was measured.

(Example 10)
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 40 g of Plascoat RZ105 in Example 1 was changed to 40 g of Plascoat RZ570 (manufactured by GOO Chemical Co., Ltd., water-dispersible polyester, solid content 25 mass%), and each surface resistance value was measured.

Example 11
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 60 g of Plascoat RZ105 was added to 40 g of the conductive polymer-containing liquid obtained in Production Example 2, a conductive film was produced, and each surface resistance value was measured.

Example 12
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that 20 g of Plascoat RZ105 was added to 80 g of the conductive polymer-containing liquid obtained in Production Example 2, a conductive film was produced, and each surface resistance value was measured.

Example 13
A conductive film was prepared in the same manner as in Example 1, and each surface resistance value was measured, except that the conductive film whose surface resistance value A was measured in Example 1 was left for 10 days under humidified conditions of a temperature of 60° C. and a humidity of 60% RH, and then the surface resistance value B was measured.
It should be noted that Examples 1 to 12 given above and Examples 14 to 19 given below are reference examples.

(Example 14)
A conductive film was prepared in the same manner as in Example 1, and each surface resistance value was measured, except that the conductive film whose surface resistance value B was measured in Example 1 was left for 10 days under non-humidified conditions at 60°C, and then the surface resistance value C was measured in the same manner as described above.

(Example 15)
The conductive film for which the surface resistance value A was measured in Example 1 was left to stand for 30 days under humidified conditions of a temperature of 85° C. and a humidity of 85% RH, and then the surface resistance value B was measured in the same manner as above. Except for this, a conductive film was produced in the same manner as in Example 1, and each surface resistance value was measured.

(Example 16)
The conductive film for which the surface resistance value B was measured in Example 1 was left to stand for 30 days under non-humidified conditions at 85° C., and then the surface resistance value C was measured in the same manner as above. Except for this, a conductive film was produced in the same manner as in Example 1, and each surface resistance value was measured.

(Comparative Example 1)
A conductive polymer-containing liquid was obtained in the same manner as in Example 1 except that methyl gallate was not added, and a conductive film was prepared and its surface resistance value was measured.

(Comparative Example 2)
A conductive polymer-containing liquid was obtained in the same manner as in Example 1, except that methyl gallate and Plascoat RZ105 were not added, and a conductive film was prepared and its surface resistance value was measured.

(Example 17)
2 g of pentaerythritol triacrylate, 0.08 g of Irgacure 184 (photopolymerization initiator, manufactured by BASF) and 0.1 g of methyl gallate were added to 98 g of the conductive polymer-containing liquid obtained in Production Example 3. The obtained conductive polymer-containing liquid was applied onto a PET film using a #8 bar coater, dried at 100°C for 1 minute, and irradiated with 400 mJ of ultraviolet light to obtain a conductive film. The surface resistance values A to C of this conductive film were measured in the same manner as in Example 1, and the results are shown in Table 2.

(Comparative Example 3)
A conductive polymer-containing liquid was obtained in the same manner as in Example 17 except that methyl gallate was not added, and a conductive film was prepared and its surface resistance value was measured.

(Comparative Example 4)
A conductive polymer-containing liquid was obtained in the same manner as in Example 17, except that pentaerythritol triacrylate and Irgacure 184 were not added, and a conductive film was produced and its surface resistance value was measured.

(Example 18)
2 g of pentaerythritol triacrylate, 0.08 g of Irgacure 184 (photopolymerization initiator, manufactured by BASF) and 0.1 g of methyl gallate were added to 98 g of the conductive polymer-containing liquid obtained in Production Example 4. The obtained conductive polymer-containing liquid was applied onto a PET film using a #8 bar coater, dried at 100°C for 1 minute, and irradiated with 400 mJ of ultraviolet light to obtain a conductive film. The surface resistance values A to C of this conductive film were measured in the same manner as in Example 1, and the results are shown in Table 3.

(Comparative Example 5)
A conductive polymer-containing liquid was obtained in the same manner as in Example 18 except that methyl gallate was not added, and a conductive film was prepared and its surface resistance value was measured.

(Comparative Example 6)
A conductive polymer-containing liquid was obtained in the same manner as in Example 18, except that pentaerythritol triacrylate and Irgacure 184 were not added, and a conductive film was produced and its surface resistance value was measured.

(Example 19)
2 g of pentaerythritol triacrylate, 0.08 g of Irgacure 184 (photopolymerization initiator, manufactured by BASF) and 0.1 g of methyl gallate were added to 98 g of the conductive polymer-containing liquid obtained in Production Example 5. The obtained conductive polymer-containing liquid was applied onto a PET film using a #8 bar coater, dried at 100°C for 1 minute, and irradiated with 400 mJ of ultraviolet light to obtain a conductive film. The surface resistance values A to C of this conductive film were measured in the same manner as in Example 1, and the results are shown in Table 4.

(Comparative Example 7)
A conductive polymer-containing liquid was obtained in the same manner as in Example 19 except that methyl gallate was not added, and a conductive film was prepared and its surface resistance value was measured.

(Comparative Example 8)
A conductive polymer-containing liquid was obtained in the same manner as in Example 19, except that pentaerythritol triacrylate and Irgacure 184 were not added, and a conductive film was produced and its surface resistance value was measured.

Claims (10)

The conductive polymer-containing liquid contains a conductive complex containing a π-conjugated conductive polymer and a polyanion, a binder component, and a conductivity enhancing agent, and is used for the purpose of producing a conductive laminate by carrying out the following steps 1 to 3 in order:
The surface resistance value B (unit: Ω/□) of the following conductive layer of the following conductive laminate B is
is lower than the surface resistance value A (unit: Ω/□) of the conductive layer of the conductive laminate A described below,
The surface resistance value C (unit: Ω/□) of the following conductive layer of the following conductive laminate C is
The surface resistance value A (unit: Ω/□) of the conductive layer of the conductive laminate A is lower than that of the conductive layer A.
Liquid containing conductive polymer.
(Process 1)
A step (step 2) of obtaining a conductive laminate A by applying the conductive polymer-containing liquid to at least a part of the surface of a substrate to form a coating film and drying the coating film to form a conductive layer.
A step of obtaining a conductive laminate B by maintaining the conductive laminate A including the substrate and the conductive layer under heated and humidified conditions of 60° C. or higher and 85° C. or lower and 60% RH or higher and lower than 70% RH for 10 days or longer and 30 days or shorter (step 3).
A process of obtaining a conductive laminate C by maintaining the conductive laminate B under heating conditions of 60° C. to 85° C. and non-humidified for 10 to 30 days to dry the conductive layer. The surface resistance value B (unit: Ω/□) of the conductive layer of the conductive laminate B is
The conductive polymer-containing liquid according to claim 1 , wherein the conductive polymer-containing liquid has a surface resistance C (unit: Ω/□) lower than that of the conductive layer of the conductive laminate C. 3. The conductive polymer-containing liquid according to claim 1, wherein the highly conductive agent is at least one selected from the group consisting of a compound having two or more hydroxyl groups, a compound having two or more carboxyl groups, a compound having an amide group, and a nitrogen-containing aromatic 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), or the polyanion is polystyrenesulfonic acid. The conductive polymer-containing liquid according to any one of claims 1 to 4 , wherein the conductive complex is modified by a reaction with one or more compounds selected from the group consisting of an epoxy compound, an amine compound, and a quaternary ammonium compound. The conductive polymer-containing liquid according to claim 1 , wherein the highly conductive agent is gallic acid or a gallic acid alkyl ester. The conductive polymer-containing liquid according to claim 6 , wherein the binder component is a water-dispersible polyester resin. A method for producing a conductive laminate, comprising: obtaining the conductive laminate C by sequentially carrying out steps 1 to 3 using the conductive polymer-containing liquid according to any one of claims 1 to 7. The method for producing a conductive laminate according to claim 8, wherein the substrate is a film substrate. A method for producing a conductive polymer-containing liquid according to claim 5 , comprising the steps of:
adding at least one compound selected from the group consisting of the epoxy compound, the amine compound, and the quaternary ammonium compound to a raw material liquid containing the conductive complex containing the π- conjugated conductive polymer and the polyanion, and an aqueous dispersion medium;
recovering a reaction product between the added compound and the conductive composite;
and mixing the reaction product, a solvent, the binder component, and the highly-conductive agent to obtain the conductive polymer-containing liquid.