JP5241997B2 - Conductive polymer solution and conductive coating film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive polymer solution which can prevent corrosion of metals, discoloration of contactants and the like from occurring, and a conductive coating film. <P>SOLUTION: The conductive polymer solution, which contains a &pi;-conjugated conductive polymer, a polyanion and a solvent, has a pH of 5-13 at 25&deg;C. The conductive coating film is formed by coating the above conductive polymer solution. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a conductive polymer solution containing a π-conjugated conductive polymer. The present invention also relates to a conductive coating for imparting conductivity to electronic parts, packaging materials, and the like.

π-conjugated conductive polymers are used in electrophotographic equipment parts such as electronic parts, general-purpose antistatic materials, antistatic packaging materials for precision electronic equipment, and transfer belts.
This π-conjugated conductive polymer alone is not soluble in a solvent, and has a so-called insoluble and infusible property that decomposes before reaching the melting point, so that film formation is difficult. In order to facilitate film formation, many methods have been proposed for dissolving a π-conjugated conductive polymer in a solvent by adding a component that solubilizes the π-conjugated conductive polymer.

For example, Patent Document 1 proposes to obtain a liquid containing polyaniline by polymerizing aniline in the presence of a polyanion having a sulfo group, a carboxy group or the like. In this polyaniline-containing liquid, since polyaniline is dispersed in the order of nm, water exhibits the same behavior as the solution in terms of appearance and performance. And since this polyaniline containing liquid is suitable as an electroconductivity provision material of a water-soluble polymer, the antistatic material which has the outstanding performance can be obtained by mixing a water-soluble polymer.
JP-A-7-105718

However, when the polyaniline-containing liquid described in Patent Document 1 is used for an application in contact with an electronic component, problems such as metal corrosion or discoloration of a contact object (for example, food) that comes into contact with a conductive polymer solution are caused. And sometimes caused it.
This invention is made | formed in view of the said situation, Comprising: It aims at providing the conductive polymer solution and conductive film which can prevent metal corrosion, discoloration of a contact material, etc.

As a result of investigating metal corrosion and discoloration of contact materials, the present inventors have found that the cause is that the pH of the solution containing the π-conjugated conductive polymer is low. Invented a protective coating.
That is, the conductive polymer solution of the present invention, in the conductive polymer solution containing a solvent [pi-conjugated conductive polymer and polyanion and a nitrogen-containing aromatic cyclic compound, [pi-conjugated conductive polymer Is one or two selected from polypyrrole, polythiophene, poly (N-methylpyrrole), poly (3-methylthiophene), poly (3-methoxythiophene), poly (3,4-ethylenedioxythiophene) A polyanion selected from polystyrene sulfonic acid, polyisoprene sulfonic acid, polyacrylic acid ethyl sulfonic acid, polyacrylic acid butyl sulfonic acid, and the nitrogen-containing aromatic cyclic compound is one Pyridines and derivatives thereof containing nitrogen atom, imidazoles and derivatives thereof containing two nitrogen atoms, pyrimidine And derivatives thereof, pyrazines and derivatives thereof, selected from triazines and derivatives thereof containing three nitrogen atoms, wherein the pH at a temperature 25 ° C. is 7-11.
The conductive polymer solution of the present invention preferably further contains a compound having at least one of a hydroxyl group, a glycidyl group, and an amino group in the molecule.
The conductive coating film of the present invention is formed by applying the above-described conductive polymer solution.

The conductive polymer solution of the present invention can prevent metal corrosion, discoloration of a contact object, and the like even though the solubility of the π-conjugated conductive polymer is sufficiently maintained. Therefore, it can be applied to the field of food such as cathode materials for functional capacitors, electronic parts such as transistors, and food packaging materials.
The conductive coating film of the present invention can prevent metal corrosion, discoloration of contact materials, and the like.

<Conductive polymer solution>
(Π-conjugated conductive polymer)
The π-conjugated conductive polymer can be used as long as the main chain is an organic polymer having a π-conjugated system. Examples thereof include polypyrroles, polythiophenes, polyacetylenes, polyphenylenes, polyphenylene vinylenes, polyanilines, polyacenes, polythiophene vinylenes, and copolymers thereof. From the viewpoint of easy polymerization and stability in air, polypyrroles, polythiophenes and polyanilines are preferred.
Even if the π-conjugated conductive polymer remains unsubstituted, sufficient conductivity can be obtained. However, in order to further improve the conductivity, an alkyl group, a carboxy group, a sulfo group, an alkoxy group, a hydroxy group, a cyano group, It is preferable to introduce a functional group such as a group into the π-conjugated conductive polymer.

  Specific examples of such π-conjugated conductive polymers include polypyrrole, poly (N-methylpyrrole), poly (3-methylpyrrole), poly (3-ethylpyrrole), and 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), poly (3-methyl-4-hexyloxypyrrole), poly (3-methyl-4-hexyloxypyrrole), 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), poly (3-iodothiophene), poly (3-cyanothiophene), poly (3 -Phenylthiophene), poly (3,4-dimethylthiophene), poly (3,4-dibuty) Ruthiophene), poly (3-hydroxythiophene), poly (3-methoxythiophene), poly (3-ethoxythiophene), poly (3-butoxythiophene), poly (3-hexyloxythiophene), poly (3-heptyl) Oxythiophene), poly (3-octyloxythiophene), poly (3-decyloxythiophene), poly (3-dodecyloxythiophene), 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-dihexyl) Oxythiophene), poly (3,4-diheptyloxythiophene), poly (3 4-dioctyloxythiophene), poly (3,4-didecyloxythiophene), poly (3,4-didodecyloxythiophene), poly (3,4-ethylenedioxythiophene), poly (3,4-propylene) Dioxythiophene), poly (3,4-butenedioxythiophene), poly (3-methyl-4-methoxythiophene), poly (3-methyl-4-ethoxythiophene), poly (3-carboxythiophene), poly (3-methyl-4-carboxythiophene), poly (3-methyl-4-carboxyethylthiophene), poly (3-methyl-4-carboxybutylthiophene), polyaniline, poly (2-methylaniline), poly (3 -Isobutylaniline), poly (2-anilinesulfonic acid), poly (3-anilinesulfonic acid), etc. It is below.

Among them, from one or two kinds selected from polypyrrole, polythiophene, poly (N-methylpyrrole), poly (3-methylthiophene), poly (3-methoxythiophene), and poly (3,4-ethylenedioxythiophene). The (co) polymer is preferably used from the viewpoints of resistance and reactivity. Furthermore, polypyrrole and poly (3,4-ethylenedioxythiophene) are more preferable because they have higher conductivity and improved heat resistance.
In addition, alkyl-substituted compounds such as poly (N-methylpyrrole) and poly (3-methylthiophene) are more preferable because solvent solubility and compatibility and dispersibility when a hydrophobic resin is added are further improved. . Further, among the alkyl groups of the alkyl-substituted compound, a methyl group is preferable because it prevents a decrease in conductivity.

The π-conjugated conductive polymer is obtained by chemical oxidative polymerization of a precursor monomer that forms a π-conjugated conductive polymer in a solvent in the presence of a suitable oxidizing agent and a polymer having an anionic group described below. Can be easily manufactured.
The precursor monomer has a π-conjugated system in the molecule, and a π-conjugated system is formed in the main chain even when polymerized by the action of an appropriate oxidizing agent. Examples thereof include pyrroles and derivatives thereof, thiophenes and derivatives thereof, anilines and derivatives thereof, and the like.
Specific examples of the precursor monomer include pyrrole, N-methylpyrrole, 3-methylpyrrole, 3-ethylpyrrole, 3-n-propylpyrrole, 3-butylpyrrole, 3-octylpyrrole, 3-decylpyrrole, 3- Dodecylpyrrole, 3,4-dimethylpyrrole, 3,4-dibutylpyrrole, 3-carboxylpyrrole, 3-methyl-4-carboxylpyrrole, 3-methyl-4-carboxyethylpyrrole, 3-methyl-4-carboxybutylpyrrole 3-hydroxypyrrole, 3-methoxypyrrole, 3-ethoxypyrrole, 3-butoxypyrrole, 3-hexyloxypyrrole, 3-methyl-4-hexyloxypyrrole, 3-methyl-4-hexyloxypyrrole, thiophene, 3 -Methylthiophene, 3-ethylthiophene, -Propylthiophene, 3-butylthiophene, 3-hexylthiophene, 3-heptylthiophene, 3-octylthiophene, 3-decylthiophene, 3-dodecylthiophene, 3-octadecylthiophene, 3-bromothiophene, 3-chlorothiophene, 3 -Iodothiophene, 3-cyanothiophene, 3-phenylthiophene, 3,4-dimethylthiophene, 3,4-dibutylthiophene, 3-hydroxythiophene, 3-methoxythiophene, 3-ethoxythiophene, 3-butoxythiophene, 3- Hexyloxythiophene, 3-heptyloxythiophene, 3-octyloxythiophene, 3-decyloxythiophene, 3-dodecyloxythiophene, 3-octadecyloxythiophene, 3,4-dihydroxythiophene 3,4-dimethoxythiophene, 3,4-diethoxythiophene, 3,4-dipropoxythiophene, 3,4-dibutoxythiophene, 3,4-dihexyloxythiophene, 3,4-diheptyloxythiophene, 3,4-dioctyloxythiophene, 3,4-didecyloxythiophene, 3,4-didodecyloxythiophene, 3,4-ethylenedioxythiophene, 3,4-propylenedioxythiophene, 3,4-butene Oxythiophene, 3-methyl-4-methoxythiophene, 3-methyl-4-ethoxythiophene, 3-carboxythiophene, 3-methyl-4-carboxythiophene, 3-methyl-4-carboxyethylthiophene, 3-methyl-4 -Carboxybutylthiophene, aniline, 2-methylaniline, Examples include 3-isobutylaniline, 2-aniline sulfonic acid, and 3-aniline sulfonic acid.

  The solvent used in the production of the π-conjugated conductive polymer is not particularly limited as long as it is a solvent that can dissolve or disperse the precursor monomer and can maintain the oxidizing power of the oxidizing agent. . For example, polar solvents such as water, N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, hexamethylene phosphortriamide, acetonitrile, benzonitrile, cresol, phenol, xylenol, etc. Phenols, alcohols such as methanol, ethanol, propanol and butanol, ketones such as acetone and methyl ethyl ketone, hydrocarbons such as hexane, benzene and toluene, carboxylic acids such as formic acid and acetic acid, ethylene carbonate, propylene carbonate, etc. Carbonate compounds, ether compounds such as dioxane, diethyl ether, ethylene glycol dialkyl ether, propylene glycol dialkyl ether, polyethylene glycol dialkyl ether Chain ethers such as polypropylene glycol dialkyl ether, 3-methyl-2-oxazolidinone heterocyclic compounds such as, acetonitrile, glutarodinitrile, methoxy acetonitrile, propionitrile, nitrile compounds such as benzonitrile and the like. These solvents may be used alone, as a mixture of two or more kinds, or as a mixture with other organic solvents.

  Any oxidizing agent may be used as long as it can oxidize the precursor monomer to obtain a π-conjugated conductive polymer. Examples thereof include ammonium peroxodisulfate, sodium peroxodisulfate, and potassium peroxodisulfate. Peroxodisulfate, ferric chloride, ferric sulfate, ferric nitrate, transition metal compounds such as cupric chloride, metal halides such as boron trifluoride, aluminum chloride, silver oxide, cesium oxide Metal oxides such as hydrogen peroxide and ozone, organic peroxides such as benzoyl peroxide, oxygen and the like.

[Polyanion]
The polyanion is a substituted or unsubstituted polyalkylene, a substituted or unsubstituted polyalkenylene, a substituted or unsubstituted polyimide, a substituted or unsubstituted polyamide, a substituted or unsubstituted polyester, and a copolymer thereof. It consists of a structural unit having a group and a structural unit having no anionic group.
The anion group of the polyanion functions as a dopant for the π-conjugated conductive polymer, and improves the conductivity and heat resistance of the π-conjugated conductive polymer.

  A polyalkylene is a polymer whose main chain is composed of repeating methylenes. Examples of the polyalkylene include polyethylene, polypropylene, polybutene, polypentene, polyhexene, polyvinyl alcohol, polyvinylphenol, poly3,3,3-trifluoropropylene, polyacrylonitrile, polyacrylate, polystyrene, and the like.

Polyalkenylene is a polymer composed of structural units containing one or more unsaturated bonds (vinyl groups) in the main chain. Specific examples of polyalkenylene include propenylene, 1-methylpropenylene, 1-butylpropenylene, 1-decylpropenylene, 1-cyanopropenylene, 1-phenylpropenylene, 1-hydroxypropenylene, 1-butenylene, 1-methyl-1-butenylene, 1-ethyl-1-butenylene, 1-octyl-1-butenylene, 1-pentadecyl-1-butenylene, 2-methyl-1-butenylene, 2-ethyl-1-butenylene, 2- Butyl-1-butenylene, 2-hexyl-1-butenylene, 2-octyl-1-butenylene, 2-decyl-1-butenylene, 2-dodecyl-1-butenylene, 2-phenyl-1-butenylene, 2-butenylene, 1-methyl-2-butenylene, 1-ethyl-2-butenylene, 1-octyl-2-butenylene 1-pentadecyl-2-butenylene, 2-methyl-2-butenylene, 2-ethyl-2-butenylene, 2-butyl-2-butenylene, 2-hexyl-2-butenylene, 2-octyl-2-butenylene, 2- Decyl-2-butenylene, 2-dodecyl-2-butenylene, 2-phenyl-2-butenylene, 2-propylenephenyl-2-butenylene, 3-methyl-2-butenylene, 3-ethyl-2-butenylene, 3-butyl 2-butenylene, 3-hexyl-2-butenylene, 3-octyl-2-butenylene, 3-decyl-2-butenylene, 3-dodecyl-2-butenylene, 3-phenyl-2-butenylene, 3-propylenephenyl- 2-butenylene, 2-pentenylene, 4-propyl-2-pentenylene, 4-butyl-2-pentenylene, 4-he Selected from sil-2-pentenylene, 4-cyano-2-pentenylene, 3-methyl-2-pentenylene, 4-ethyl-2-pentenylene, 3-phenyl-2-pentenylene, 4-hydroxy-2-pentenylene, hexenylene, etc. And a polymer containing one or more structural units.
Among these, substituted or unsubstituted butenylene is preferable because of the interaction between the unsaturated bond and the π-conjugated conductive polymer and the ease of synthesis using substituted or unsubstituted butadiene as a starting material.

As polyimide, pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, 2,2,3,3-tetracarboxydiphenyl ether dianhydride, 2,2- [4,4 Examples include polyimides from anhydrides such as' -di (dicarboxyphenyloxy) phenyl] propane dianhydride and diamines such as oxydianine, paraphenylenediamine, metaphenylenediamine, and benzophenonediamine.
Examples of the polyamide include polyamide 6, polyamide 6,6, polyamide 6,10 and the like.
Examples of the polyester include polyethylene terephthalate and polybutylene terephthalate.

When the polyanion has a substituent, examples of the substituent include an alkyl group, a hydroxy group, an amino group, a carboxy group, a cyano group, a phenyl group, a phenol group, an ester group, and an alkoxy group. In view of solubility in a solvent, heat resistance, compatibility with a resin, and the like, an alkyl group, a hydroxy group, a phenol group, and an ester group are preferable.
Alkyl groups can increase solubility and dispersibility in polar or nonpolar solvents, compatibility and dispersibility in resins, and hydroxy groups form hydrogen bonds with other hydrogen atoms. This makes it easy to increase solubility in organic solvents, compatibility with resins, dispersibility, and adhesion. In addition, the cyano group and the hydroxyphenyl group can increase the compatibility and solubility in the polar resin, and can also increase the heat resistance.
Among the above substituents, an alkyl group, a hydroxy group, an ester group, and a cyano group are preferable.

Examples of the alkyl group include chain alkyl groups such as methyl, ethyl, propyl, butyl, isobutyl, t-butyl, pentyl, hexyl, octyl, decyl, and dodecyl, and cycloalkyl groups such as cyclopropyl, cyclopentyl, and cyclohexyl. . In consideration of solubility in an organic solvent, dispersibility in a resin, steric hindrance, and the like, an alkyl group having 1 to 12 carbon atoms is more preferable.
Examples of the hydroxy group include a hydroxy group directly bonded to the main chain of the polyanion or a hydroxy group bonded via another functional group. Examples of other functional groups include an alkyl group having 1 to 7 carbon atoms, an alkenyl group having 2 to 7 carbon atoms, an amide group, and an imide group. The hydroxy group is substituted at the end or in these functional groups. Among these, a hydroxy group bonded to the terminal of an alkyl group having 1 to 6 carbon atoms bonded to the main chain is more preferable from the viewpoint of compatibility with a resin and solubility in an organic solvent.
Examples of the amino group include an amino group directly bonded to the main chain of the polyanion or an amino group bonded via another functional group. Examples of other functional groups include an alkyl group having 1 to 7 carbon atoms, an alkenyl group having 2 to 7 carbon atoms, an amide group, and an imide group. The amino group is substituted at the end or in these functional groups.
Examples of the phenol group include a phenol group directly bonded to the main chain of the polyanion or a phenol group bonded via another functional group. Examples of other functional groups include an alkyl group having 1 to 7 carbon atoms, an alkenyl group having 2 to 7 carbon atoms, an amide group, and an imide group. The phenol group is substituted at the end or in these functional groups.
Examples of the ester group include an alkyl ester group directly bonded to the main chain of the polyanion, an aromatic ester group, and an alkyl ester group or an aromatic ester group having another functional group interposed therebetween.
The cyano group includes a cyano group directly bonded to the main chain of the polyanion, a cyano group bonded to the terminal of the alkyl group having 1 to 7 carbon atoms bonded to the main chain of the polyanion, and 2 to 2 carbon atoms bonded to the main chain of the polyanion. And a cyano group bonded to the terminal of 7 alkenyl group.

  The anion group of the polyanion may be a functional group capable of undergoing chemical oxidation doping to the π-conjugated conductive polymer. Among them, from the viewpoint of ease of production and stability, a monosubstituted sulfate group, A monosubstituted phosphate group, a phosphate group, a carboxy group, a sulfo group and the like are preferable. Furthermore, from the viewpoint of the doping effect of the functional group on the π-conjugated conductive polymer, a sulfo group, a monosubstituted sulfate group, and a carboxy group are more preferable.

Specific examples of polyanions include polyvinyl sulfonic acid, polystyrene sulfonic acid, polyallyl sulfonic acid, polyacrylic acid ethyl sulfonic acid, polyacrylic acid butyl sulfonic acid, polyacryl sulfonic acid, polymethacryl sulfonic acid, poly-2-acrylamide- 2-methylpropanesulfonic acid, polyisoprenesulfonic acid, polyvinyl carboxylic acid, polystyrene carboxylic acid, polyallyl carboxylic acid, polyacryl carboxylic acid, polymethacryl carboxylic acid, poly-2-acrylamido-2-methylpropane carboxylic acid, polyisoprene Examples thereof include carboxylic acid and polyacrylic acid. These homopolymers may be sufficient and 2 or more types of copolymers may be sufficient.
Among these, polystyrene sulfonic acid, polyisoprene sulfonic acid, polyacrylic acid ethyl sulfonic acid, and polyacrylic acid butyl sulfonic acid are preferable. These polyanions can mitigate thermal decomposition of the π-conjugated conductive polymer.

  The degree of polymerization of the polyanion is preferably in the range of 10 to 100,000 monomer units, and more preferably in the range of 50 to 10,000 from the viewpoint of solvent solubility and conductivity.

Examples of methods for producing polyanions include a method of directly introducing an anionic group into a polymer having no anionic group using an acid, a method of sulfonating a polymer having no anionic group with a sulfonating agent, and anionic group-containing polymerization. And a method of production by polymerization of a functional monomer.
Examples of the method for producing an anion group-containing polymerizable monomer by polymerization include a method for producing an anion group-containing polymerizable monomer in a solvent by oxidative polymerization or radical polymerization in the presence of an oxidizing agent and / or a polymerization catalyst. Specifically, a predetermined amount of the anionic group-containing polymerizable monomer is dissolved in a solvent, kept at a constant temperature, and a solution in which a predetermined amount of an oxidizing agent and / or a polymerization catalyst is dissolved in the solvent is added to the predetermined amount. React with time. The polymer obtained by the reaction is adjusted to a certain concentration by the solvent. In this production method, an anionic group-containing polymerizable monomer may be copolymerized with a polymerizable monomer having no anionic group.
The oxidizing agent and solvent used in the polymerization of the anionic group-containing polymerizable monomer are the same as those used in the polymerization of the precursor monomer that forms the π-conjugated conductive polymer.
When the obtained polymer is a polyanionic salt, it is preferably transformed into a polyanionic acid. Examples of the method for transforming into an anionic acid include an ion exchange method using an ion exchange resin, a dialysis method, an ultrafiltration method, and the like. Among these, an ultrafiltration method is preferable from the viewpoint of easy work.

The anionic group-containing polymerizable monomer is one in which a part of the monomer is substituted with a mono-substituted sulfate group, a carboxy group, a sulfo group, etc., for example, a substituted or unsubstituted ethylene sulfonic acid compound, a substituted or unsubstituted Styrene sulfonic acid compound, substituted or unsubstituted acrylate sulfonic acid compound, substituted or unsubstituted methacrylate sulfonic acid compound, substituted or unsubstituted acrylamide sulfonic acid compound, substituted or unsubstituted cyclovinylene sulfonic acid compound, substituted or unsubstituted And a substituted or unsubstituted vinyl aromatic sulfonic acid compound.
Specifically, vinyl sulfonic acid and salts thereof, allyl sulfonic acid and salts thereof, methallyl sulfonic acid and salts thereof, styrene sulfonic acid, methallyloxybenzene sulfonic acid and salts thereof, allyloxybenzene sulfonic acid and salts thereof, α-methylstyrenesulfonic acid and its salts, acrylamide-t-butylsulfonic acid and its salts, 2-acrylamido-2-methylpropanesulfonic acid and its salts, cyclobutene-3-sulfonic acid and its salts, isoprenesulfonic acid and its Salts, 1,3-butadiene-1-sulfonic acid and its salts, 1-methyl-1,3-butadiene-2-sulfonic acid and its salts, 1-methyl-1,3-butadiene-4-sulfonic acid and its salts, ethyl acrylate sulfonic acid _{(CH 2 CH-COO- (CH} 2 ₂ -SO ₃ H) and its salts, acrylic acid propyl sulfonic acid _{(CH 2 CH-COO- (CH} 2) 3 -SO 3 H) and its salts, acrylic acid -t- butyl sulfonic acid _(CH 2 _{CH-COO -C (CH 3) 2 CH 2} -SO 3 H) and its salts, acrylic acid -n- butyl sulfonic acid _{(CH 2 CH-COO- (CH} 2) 4 -SO 3 H) and salts thereof, ethyl allyl acid sulfonic acid _{(CH 2 CHCH 2 -COO- (CH} 2) 2 -SO 3 H) and its salts, allyl acid -t- butyl sulfonic acid _{(CH 2 CHCH 2 -COO-C} (CH 3) 2 CH 2 -SO ₃ H) and salts thereof, 4-pentenoic acid ethylsulfonic acid (CH ₂ CH (CH ₂ ) ₂ —COO— (CH ₂ ) ₂ —SO ₃ H) and salts thereof, 4-pentenoic acid propyl sulfonic acid (CH ₂ CH (CH ₂ ) ₂ —COO— (CH ₂ ) ₃ -SO ₃ H) and salts thereof, 4-pentenoic acid-n-butylsulfonic acid (CH ₂ CH (CH ₂ ) ₂ —COO— (CH ₂ ) ₄ —SO ₃ H) and salts thereof, 4-pentene Acid-t-butyl sulfonic acid (CH ₂ CH (CH ₂ ) ₂ —COO—C (CH ₃ ) ₂ CH ₂ —SO ₃ H) and its salts, 4-pentenoic acid phenylene sulfonic acid (CH ₂ CH (CH _{2 2} ) -COO—C ₆ H ₄ —SO ₃ H) and salts thereof, 4-pentenoic acid naphthalenesulfonic acid (CH ₂ CH (CH ₂ ) ₂ —COO—C ₁₀ H ₈ —SO ₃ H) and salts thereof, Ethyl methacrylate sulfonic acid (CH ₂ C (CH ₃ ) —COO— (CH ₂ ) ₂ —SO ₃ H) and salts thereof, propyl methacrylate methacrylate (CH ₂ C (CH ₃ ) —COO— (CH ₂ ) ₃ -SO ₃ H) and its salts, methacrylic acid-t-butylsulfate Acid _{(CH 2 C (CH 3)} -COO-C (CH 3) 2 CH 2 -SO 3 H) and its salts, methacrylic acid -n- butyl sulfonic acid _{(CH 2 C (CH 3)} -COO- ( CH ₂ ) ₄ —SO ₃ H) and salts thereof, phenylene sulfonic acid methacrylate (CH ₂ C (CH ₃ ) —COO—C ₆ H ₄ —SO ₃ H) and salts thereof, naphthalene sulfonic acid methacrylate (CH ₂₎ C (CH ₃ ) —COO—C ₁₀ H ₈ —SO ₃ H) and salts thereof, polyvinyl carboxylic acid, polystyrene carboxylic acid, polyallyl carboxylic acid, polyacryl carboxylic acid, polymethacryl carboxylic acid, poly-2-acrylamide— Examples include 2-methylpropanecarboxylic acid, polyisoprene carboxylic acid, polyacrylic acid and the like. Moreover, the copolymer containing 2 or more types of these may be sufficient.

Examples of the polymerizable monomer having no anionic group include ethylene, propene, 1-butene, 2-butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, styrene, p-methylstyrene, p. -Ethylstyrene, p-butylstyrene, 2,4,6-trimethylstyrene, p-methoxystyrene, α-methylstyrene, 2-vinylnaphthalene, 6-methyl-2-vinylnaphthalene, 1-vinylimidazole, vinylpyridine, Vinyl acetate, acrylaldehyde, acrylonitrile, N-vinyl-2-pyrrolidone, N-vinylacetamide, N-vinylformamide, N-vinylimidazole, acrylamide, N, N-dimethylacrylamide, acrylic acid, methyl acrylate, Ethyl acrylate, propyl acrylate, acrylic acid -Butyl, i-butyl acrylate, t-butyl acrylate, i-octyl acrylate, isononyl butyl acrylate, lauryl acrylate, allyl acrylate, stearyl acrylate, isobornyl acrylate, cyclohexyl acrylate, benzyl acrylate , Ethyl carbitol acrylate, phenoxyethyl acrylate, hydroxyethyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, methoxybutyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, methacryl I-Butyl acid, t-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, methacrylic acid Benzyl, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, acryloylmorpholine, vinylamine, N, N-dimethylvinylamine, N, N-diethylvinylamine, N, N-dibutylvinylamine, N, N-di -T-butylvinylamine, N, N-diphenylvinylamine, N-vinylcarbazole, vinyl alcohol, vinyl chloride, vinyl fluoride, methyl vinyl ether, ethyl vinyl ether, cyclopropene, cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene, 2-methylcyclohexene, vinylphenol, 1,3-butadiene, 1-methyl-1,3-butadiene, 2-methyl-1,3-butadiene, 1,4-dimethyl-1,3-butadiene, 1,2- Dimethyl , 3-butadiene, 1,3-dimethyl-1,3-butadiene, 1-octyl-1,3-butadiene, 2-octyl-1,3-butadiene, 1-phenyl-1,3-butadiene, 2-phenyl -1,3-butadiene, 1-hydroxy-1,3-butadiene, 2-hydroxy-1,3-butadiene and the like.
Solvent solubility can be controlled by copolymerizing these polymerizable monomers having no anionic group.

  The ratio of the π-conjugated conductive polymer and the polyanion in the conductive polymer solution is preferably 1 to 1000 parts by mass of the π-conjugated conductive polymer with respect to 100 parts by mass of the polyanion. When the π-conjugated conductive polymer is less than 1 part by mass, the conductivity tends to be insufficient, and when it exceeds 1000 parts by mass, the solvent solubility tends to be insufficient.

(Dopant)
In the conductive polymer solution, the polyanion functions as a dopant for the π-conjugated conductive polymer, but the conductive polymer solution may contain a dopant other than the polyanion (hereinafter referred to as other dopant). .
Other dopants may be donor or acceptor as long as the π-conjugated conductive polymer can be oxidized and reduced.

[Donor dopant]
Examples of the donor dopant include alkali metals such as sodium and potassium, alkaline earth metals such as calcium and magnesium, tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, methyltriethylammonium, dimethyldiethylammonium, and the like. A quaternary amine compound etc. are mentioned.

[Acceptor dopant]
As the acceptor dopant, for example, a halogen compound, Lewis acid, proton acid, organic cyano compound, organometallic compound, fullerene, hydrogenated fullerene, hydroxylated fullerene, carboxylated fullerene, sulfonated fullerene, or the like can be used.
Furthermore, examples of the halogen compound include chlorine (Cl ₂ ), bromine (Br ₂ ), iodine (I ₂ ), iodine chloride (ICl), iodine bromide (IBr), and iodine fluoride (IF). .
Examples of the Lewis acid include PF ₅ , AsF ₅ , SbF ₅ , BF ₅ , BCl ₅ , BBr ₅ , SO _{3 and the} like.
As the organic cyano compound, a compound containing two or more cyano groups in a conjugated bond can be used. Examples include tetracyanoethylene, tetracyanoethylene oxide, tetracyanobenzene, dichlorodicyanobenzoquinone (DDQ), tetracyanoquinodimethane, and tetracyanoazanaphthalene.

  Examples of the protonic acid include inorganic acids and organic acids. Furthermore, examples of the inorganic acid include hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, borohydrofluoric acid, hydrofluoric acid, and perchloric acid. Examples of organic acids include organic carboxylic acids, phenols, and organic sulfonic acids.

  As the organic carboxylic acid, aliphatic, aromatic, cycloaliphatic and the like containing one or more carboxy groups can be used. For example, formic acid, acetic acid, oxalic acid, benzoic acid, phthalic acid, maleic acid, fumaric acid, malonic acid, tartaric acid, citric acid, lactic acid, succinic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, nitroacetic acid, And triphenylacetic acid.

As the organic sulfonic acid, aliphatic, aromatic, cycloaliphatic or the like containing one or more sulfo groups, or a polymer containing sulfo groups can be used.
As one containing one sulfo group, for example, methanesulfonic acid, ethanesulfonic acid, 1-propanesulfonic acid, 1-butanesulfonic acid, 1-hexanesulfonic acid, 1-heptanesulfonic acid, 1-octanesulfonic acid, 1 -Nonanesulfonic acid, 1-decanesulfonic acid, 1-dodecanesulfonic acid, 1-tetradecanesulfonic acid, 1-pentadecanesulfonic acid, 2-bromoethanesulfonic acid, 3-chloro-2-hydroxypropanesulfonic acid, trifluoromethanesulfone Acid, trifluoroethanesulfonic acid, colistin methanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, aminomethanesulfonic acid, 1-amino-2-naphthol-4-sulfonic acid, 2-amino-5-naphthol- 7-sulfonic acid, 3-aminopropanesulfone N-cyclohexyl-3-aminopropanesulfonic acid, benzenesulfonic acid, alkylbenzenesulfonic acid, p-toluenesulfonic acid, xylenesulfonic acid, ethylbenzenesulfonic acid, propylbenzenesulfonic acid, butylbenzenesulfonic acid, pentylbenzenesulfonic acid, hex Tylbenzenesulfonic acid, heptylbenzenesulfonic acid, octylbenzenesulfonic acid, nonylbenzenesulfonic acid, decylbenzenesulfonic acid, undecylbenzenesulfonic acid, dodecylbenzenesulfonic acid, pentadecylbenzenesulfonic acid, hexadecylbenzenesulfonic acid, 2, 4-dimethylbenzenesulfonic acid, dipropylbenzenesulfonic acid, 4-aminobenzenesulfonic acid, o-aminobenzenesulfonic acid, m-aminobenzenesulfonic acid 4-amino-2-chlorotoluene-5-sulfonic acid, 4-amino-3-methylbenzene-1-sulfonic acid, 4-amino-5-methoxy-2-methylbenzenesulfonic acid, 2-amino-5-methyl Benzene-1-sulfonic acid, 4-amino-2-methylbenzene-1-sulfonic acid, 5-amino-2-methylbenzene-1-sulfonic acid, 4-amino-3-methylbenzene-1-sulfonic acid, 4 -Acetamide-3-chlorobenzenesulfonic acid, 4-chloro-3-nitrobenzenesulfonic acid, p-chlorobenzenesulfonic acid, naphthalenesulfonic acid, methylnaphthalenesulfonic acid, propylnaphthalenesulfonic acid, butylnaphthalenesulfonic acid, pentylnaphthalenesulfonic acid, 4 -Amino-1-naphthalenesulfonic acid, 8-chloronaphthalene-1- Examples include sulfonic acid, naphthalene sulfonic acid formalin polycondensate, melamine sulfonic acid formalin polycondensate, anthraquinone sulfonic acid, and pyrene sulfonic acid. These metal salts can also be used.

  Examples of those containing two or more sulfo groups include ethanedisulfonic acid, butanedisulfonic acid, pentanedisulfonic acid, decanedisulfonic acid, o-benzenedisulfonic acid, m-benzenedisulfonic acid, p-benzenedisulfonic acid, and toluenedisulfonic acid. , Xylene disulfonic acid, chlorobenzene disulfonic acid, fluorobenzene disulfonic acid, dimethylbenzene disulfonic acid, diethylbenzene disulfonic acid, aniline-2,4-disulfonic acid, aniline-2,5-disulfonic acid, 3,4-dihydroxy-1,3 Benzene disulfonic acid, naphthalene disulfonic acid, methyl naphthalene disulfonic acid, ethyl naphthalene disulfonic acid, pentadecyl naphthalene disulfonic acid, 3-amino-5-hydroxy-2,7-naphthalene disulfonic acid, 1- Cetamide-8-hydroxy-3,6-naphthalenedisulfonic acid, 2-amino-1,4-benzenedisulfonic acid, 1-amino-3,8-naphthalenedisulfonic acid, 3-amino-1,5-naphthalenedisulfonic acid, 8-Amino-1-naphthol-3,6-disulfonic acid, 4-amino-5-naphthol-2,7-disulfonic acid, 4-acetamido-4'-isothio-cyanotostilbene-2,2'-disulfonic acid 4-acetamido-4′-isothiocyanatostilbene-2,2′-disulfonic acid, 4-acetamido-4′-maleimidylstilbene-2,2′-disulfonic acid, naphthalenetrisulfonic acid, dinaphthylmethanedisulfone An acid, anthraquinone disulfonic acid, anthracene sulfonic acid, etc. are mentioned. These metal salts can also be used.

(solvent)
As a solvent contained in the conductive polymer solution, a solvent having a solubility parameter (SP value) of 10 or more is preferable. SP values of 10 or more include water, alcohols such as methanol, ethanol, ethylene glycol, and diethylene glycol, fatty acids such as succinic anhydride and maleic anhydride, N-methylformamide, methylacetamide, acetonitrile, and the like. Nitrogen compounds, ethylene carbonate, propylene carbonate are mentioned. 1 type may be sufficient as a solvent, and 2 or more types may be sufficient as it.
The solvent is particularly preferably a solvent that dissolves the polyanion and the precursor monomer and dissolves the oxidizing agent to advance the polymerization of the precursor monomer.

(PH of conductive polymer solution)
The conductive polymer solution is adjusted so that the pH at 25 ° C. is 5 to 13, preferably 7 to 11. If the pH is less than 5, metal corrosion or discoloration of the contact cannot be prevented, and if it exceeds 13, the polyanion is dedoped and the conductivity is insufficient.
Examples of methods for adjusting the pH include a method of forming a salt by mixing an alkali with an aqueous solution of a complex of a π-conjugated conductive polymer and a polyanion (hereinafter referred to as an aqueous complex solution), and an acid group as an ester. And a method of amidating an acid group.

The alkali in the case of mixing the alkali is not particularly limited, and a known inorganic alkali or organic alkali can be used. Examples of the inorganic alkali include sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia and the like. Examples of the organic alkali include aliphatic amines such as ethylamine, diethylamine, methylethylamine, and triethylamine, aromatic amines such as aniline, benzylamine, pyrrole, imidazole, and pyridine, or derivatives thereof, pyrrole, sodium methoxide, and the like. And metal alkoxides such as sodium alkoxide such as sodium ethoxide, potassium alkoxide and calcium alkoxide.
Among these, weakly basic aliphatic amines, aromatic amines, and metal alkoxides are preferable.

Furthermore, a nitrogen-containing aromatic cyclic compound can be suitably used as the organic alkali. The nitrogen-containing aromatic cyclic compound can not only prevent de-doping of the polyanion, but can also improve conductivity.
Here, the nitrogen-containing aromatic cyclic compound has an aromatic ring containing at least one nitrogen atom, and the nitrogen atom in the aromatic ring is conjugated with other atoms in the aromatic ring. It has a relationship. In order to become a conjugated relationship, the nitrogen atom and other atoms form an unsaturated bond. Alternatively, even if the nitrogen atom does not directly form an unsaturated bond with another atom, it may be adjacent to the other atom that forms the unsaturated bond. This is because an unshared electron pair existing on a nitrogen atom can form a pseudo conjugate relationship with an unsaturated bond formed between other atoms.
The nitrogen-containing aromatic cyclic compound preferably has both a nitrogen atom having a conjugated relationship with another atom and a nitrogen atom adjacent to the other atom forming the unsaturated bond.

Examples of such nitrogen-containing aromatic cyclic compounds include pyridines and derivatives thereof containing one nitrogen atom, imidazoles and derivatives thereof containing two nitrogen atoms, pyrimidines and derivatives thereof, and pyrazines. And derivatives thereof, triazines containing three nitrogen atoms, and derivatives thereof. From the viewpoint of solvent solubility and the like, pyridines and derivatives thereof, imidazoles and derivatives thereof, and pyrimidines and derivatives thereof are preferable.
Further, the nitrogen-containing aromatic cyclic compound may be one in which a substituent such as an alkyl group, a hydroxy group, a carboxy group, a cyano group, a phenyl group, a phenol group, an ester group, an alkoxy group, or a carbonyl group is introduced into the ring. It may be good or not introduced. The ring may be polycyclic.

Among the substituents, the alkyl group includes alkyl groups such as methyl, ethyl, propyl, butyl, isobutyl, t-butyl, pentyl, hexyl, octyl, decyl, and dodecyl, and cycloalkyl groups such as cyclopropyl, cyclopentyl, and cyclohexyl. Can be mentioned. Among these, in view of solubility in an organic solvent, dispersibility in a resin, steric hindrance, and the like, an alkyl group having 1 to 12 carbon atoms is preferable.
Examples of the hydroxy group include hydroxy, methylene hydroxy, ethylene hydroxy, trimethylene hydroxy, tetramethylene hydroxy, pentamethylene hydroxy, hexamethylene hydroxy, heptamethylene hydroxy, propylene hydroxy, butylene hydroxy, ethylmethylene hydroxy and other alkylene hydroxy groups, propenylene Alkenylene hydroxy groups such as hydroxy, butenylene hydroxy, pentenylene hydroxy and the like can be mentioned.
Examples of the carboxy group include carboxy, methylene carboxy, ethylene carboxy, trimethylene carboxy, propylene carboxy, tetramethylene carboxy, pentamethylene carboxy, hexamethylene carboxy, heptamethyl carboxy, ethyl methylene carboxy, phenylethylene carboxy, etc. And alkenylene carboxy groups such as propenylene carboxy, butenylene carboxy, and pentenylene carboxy.

Examples of the cyano group include alkylene cyano groups such as cyano, methylene cyano, ethylene cyano, trimethylene cyano, tetramethylene cyano, pentamethylene cyano, hexamethylene cyano, heptamethylene cyano, propylene cyano, butylene cyano, ethyl methylene cyano, and propenylene. Examples include alkenylene cyano groups such as cyano, butenylene cyano, and pentenylene cyano.
Examples of the phenol group include alkylphenol groups such as phenol, methylphenol, ethylphenol and butylphenol, and alkylenephenol groups such as methylenephenol, ethylenephenol, trimethylenephenol, tetramethylenephenol, pentamethylenephenol and hexamethylenephenol.
Examples of the phenyl group include alkylphenyl groups such as phenyl, methylphenyl, butylphenyl, octylphenyl, and dimethylphenyl, and methylenephenyl, ethylenephenyl, trimethylenephenyl, tetramethylenephenyl, pentamethylenephenyl, hexamethylenephenyl, and heptamethylene. Examples thereof include alkylenephenyl groups such as phenyl, and alkenylenephenyls such as propenylenephenyl, butenylenephenyl, and pentenylenephenyl.
Examples of the alkoxy group include methoxy, ethoxy, butoxy, phenoxy and the like.

  Specific examples of pyridines and derivatives thereof include pyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 4-ethylpyridine, 2,4-dimethylpyridine, 2,4,6-trimethylpyridine. , 3-cyano-5-methylpyridine, 2-pyridinecarboxylic acid, 6-methyl-2-pyridinecarboxylic acid, 2,6-pyridine-dicarboxylic acid, 4-pyridinecarboxaldehyde, 4-aminopyridine, 2,3- Diaminopyridine, 2,6-diaminopyridine, 2,6-diamino-4-methylpyridine, 4-hydroxypyridine, 2,6-dihydroxypyridine, methyl 6-hydroxynicotinate, 2-hydroxy-5-pyridinemethanol, 6 -Ethyl hydroxynicotinate, 4-pyridinemethanol, 4-pyridineethanol, 2-phenylpyridine, 3-methylquinoline, 3-ethylquinoline, quinolinol, 2,3-cyclopentenopyridine, 2,3-cyclohexanopyridine, 1,2-di (4-pyridyl) ethane, 1,2- Di (4-pyridyl) propane, 2-pyridinecarboxaldehyde, 2-pyridinecarboxylic acid, 2-pyridinecarbonitrile, 2,3-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, Examples include 2,6-pyridinedicarboxylic acid and 3-pyridinesulfonic acid.

  Specific examples of imidazoles and derivatives thereof include imidazole, 2-methylimidazole, 2-propylimidazole, 2-undecylimidazole, 2-phenylimidazole, N-methylimidazole, 1- (2-hydroxyethyl) imidazole. 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2- Ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 1-acetylimidazole, 4,5-imidazole dicarboxylic acid, dimethyl 4,5-imidazole dicarboxylate, benzimidazole, 2-aminobenz Imidazole, 2-amino-base lens imidazole-2-sulfonic acid, 2-amino-1-methyl-base lens imidazole, 2-hydroxy-base lens imidazole, 2- (2-pyridyl) base lens and imidazole.

  Specific examples of pyrimidines and derivatives thereof include 2-amino-4-chloro-6-methylpyrimidine, 2-amino-6-chloro-4-methoxypyrimidine, 2-amino-4,6-dichloropyrimidine, 2-amino-4,6-dihydroxypyrimidine, 2-amino-4,6-dimethylpyrimidine, 2-amino-4,6-dimethoxypyrimidine, 2-aminopyrimidine, 2-amino-4-methylpyrimidine, 4,6 -Dihydroxypyrimidine, 2,4-dihydroxypyrimidine-5-carboxylic acid, 2,4,6-triaminopyrimidine, 2,4-dimethoxypyrimidine, 2,4,5-trihydroxypyrimidine, 2,4-pyrimidinediol, etc. Is mentioned.

  Specific examples of the pyrazines and derivatives thereof include pyrazine, 2-methylpyrazine, 2,5-dimethylpyrazine, pyrazinecarboxylic acid, 2,3-pyrazinedicarboxylic acid, 5-methylpyrazinecarboxylic acid, pyrazineamide, 5 -Methylpyrazineamide, 2-cyanopyrazine, aminopyrazine, 3-aminopyrazine-2-carboxylic acid, 2-ethyl-3-methylpyrazine, 2-ethyl-3-methylpyrazine, 2,3-dimethylpyrazine, 2, Examples include 3-diethylpyrazine.

  Specific examples of triazines and derivatives thereof include 1,3,5-triazine, 2-amino-1,3,5-triazine, 3-amino-1,2,4-triazine, and 2,4-diamino. -6-phenyl-1,3,5-triazine, 2,4,6-triamino-1,3,5-triazine, 2,4,6-tris (trifluoromethyl) -1,3,5-triazine, 2,4,6-tri-2-pyridine-1,3,5-triazine, 3- (2-pyridine) -5,6-bis (4-phenylsulfonic acid) -1,2,4-triazine disodium 3- (2-pyridine) -5,6-diphenyl-1,2,4-triazine, 3- (2-pyridine) -5,6-diphenyl-1,2,4-triazine-ρ, ρ′- Disodium disulphonate, 2-hydroxy-4,6-dichloro -1,3,5-triazine and the like.

Since a non-shared electron pair exists in the nitrogen atom in the nitrogen-containing aromatic cyclic compound, a substituent or a proton is easily coordinated or bonded on the nitrogen atom. When a substituent or proton is coordinated or bonded to a nitrogen atom, it tends to have a cationic charge on the nitrogen atom. Here, since the nitrogen atom and other atoms have a conjugated relationship, the cation charge generated by the coordination or bonding of a substituent or a proton on the nitrogen atom is contained in the nitrogen-containing aromatic ring. Once diffused, it will exist in a stable form.
For this reason, in the nitrogen-containing aromatic cyclic compound, a substituent may be introduced into the nitrogen atom to form a nitrogen-containing aromatic cyclic compound cation. Further, a salt may be formed by combining the cation and the anion. Even if it is a salt, the same effect as a nitrogen-containing aromatic cyclic compound which is not a cation is exhibited.

Examples of the substituent introduced into the nitrogen atom of the nitrogen-containing aromatic cyclic compound include hydrogen, alkyl group, hydroxy group, carboxy group, cyano group, phenyl group, phenol group, ester group, alkoxy group, carbonyl group and the like. Can be mentioned.
Examples of the alkyl group include alkyl groups such as methyl, ethyl, propyl, butyl, isobutyl, t-butyl, pentyl, hexyl, octyl, decyl, and dodecyl, and cycloalkyl groups such as cyclopropyl, cyclopentyl, and cyclohexyl. In consideration of solubility in an organic solvent, dispersibility in a resin, steric hindrance, and the like, an alkyl group having 1 to 12 carbon atoms is more preferable.
Examples of the hydroxy group include hydroxy, methylene hydroxy, ethylene hydroxy, trimethylene hydroxy, tetramethylene hydroxy, pentamethylene hydroxy, hexamethylene hydroxy, heptamethylene hydroxy, propylene hydroxy, butylene hydroxy, ethylmethylene hydroxy and other alkylene hydroxy groups, propenylene Alkenylene hydroxy groups such as hydroxy, butenylene hydroxy, pentenylene hydroxy and the like can be mentioned.
Examples of the carboxy group include carboxy, methylene carboxy, ethylene carboxy, trimethylene carboxy, propylene carboxy, tetramethylene carboxy, pentamethylene carboxy, hexamethylene carboxy, heptamethylene carboxy, ethyl methylene carboxy, phenyl ethylene carboxy and the like, isoprene Alkenylene carboxy groups such as carboxy, propenylene carboxy, butenylene carboxy, pentenylene carboxy and the like can be mentioned.

Examples of the cyano group include alkylene cyano groups such as cyano, methylene cyano, ethylene cyano, trimethylene cyano, tetramethylene cyano, pentamethylene cyano, hexamethylene cyano, heptamethylene cyano, propylene cyano, butylene cyano, ethyl methylene cyano, and propylene. Alkenylene cyano groups such as nylene cyano, butenylene cyano, pentenylene cyano and the like can be mentioned.
Examples of the phenol group include alkylphenol groups such as phenol, methylphenol, ethylphenol, and butylphenol, and alkylenephenol groups such as methylenephenol, ethylenephenol, trimethylenephenol, tetramethylenephenol, pentamethylenephenol, and hexamethylenephenol. .
Examples of the phenyl group include alkylphenyl groups such as phenyl, methylphenyl, butylphenyl, octylphenyl, dimethylphenyl, methylenephenyl, ethylenephenyl, trimethylenephenyl, tetramethylenephenyl, pentamethylenephenyl, hexamethylenephenyl, heptamethylenephenyl, etc. And alkenylene phenyl such as propenylene phenyl, butenylene phenyl, and pentenylene phenyl.
Examples of the alkoxy group include methoxy, ethoxy, butoxy, phenoxy and the like.

As a method of esterifying or amidating an acid group, a compound having a functional group that forms an ester bond with an acid group in a complex aqueous solution (a compound having a hydroxyl group in the molecule, a compound having a glycidyl group in the molecule) or an amide Examples include a method in which a compound having a functional group that forms a bond (a compound having a glycidyl group in the molecule) is added and reacted.
Examples of the compound having a hydroxyl group in the molecule include aliphatic alcohols such as methanol, ethanol, propanol, trichloroethanol, trifluoroethanol, hydroxyethyl acrylate, and hydroxyethyl acrylamide, benzyl alcohol, phenol, hydroquinone, pyrogallol, resorcinol, Aromatic alcohols such as pyrocatechol, phenolic hydroxyl group-containing compounds, amino alcohols such as ethanolamine, diethanolamine, and triethanolamine can be used.
Examples of the compound having a glycidyl group in the molecule include ethyl glycidyl ether, butyl glycidyl ether, t-butyl glycidyl ether, allyl glycidyl ether, benzyl glycidyl ether, glycidyl phenyl ether, bisphenol A, diglycidyl ether, and glycidyl methacrylate methacrylate. And the like.
Examples of the compound having an amino group in the molecule include amine compounds such as the aforementioned amino alcohols, ethylamine, aniline, and benzylamine.

  Among these, an aliphatic alcohol or a phenolic hydroxyl group-containing compound is preferable because the conductivity of the π-conjugated conductive polymer can be improved. Furthermore, a phenolic hydroxyl group-containing compound is particularly preferable because it has an antioxidant function and can improve heat resistance and long-term stability. In addition, compounds with acrylic groups such as hydroxyethyl acrylamide and hydroxyethyl acrylate can crosslink π-conjugated conductive polymers when used in combination with light or initiator, improving thermal and mechanical properties. It is preferable at the point which can be made.

(Method for producing conductive polymer solution)
As a method for producing a conductive polymer solution, for example, first, a polyanion is dissolved in water or a solvent, and a precursor monomer of a π-conjugated conductive polymer and, if necessary, a dopant are added to the resulting solution. Then, after sufficiently stirring and mixing, an oxidizing agent is dropped to polymerize the precursor monomer. The obtained π-conjugated conductive polymer forms a complex with the polyanion and has solvent solubility.
Next, after the polymerization is completed, the oxidizing agent, residual monomers, and by-products are removed and purified, and the conductive polymer solution is obtained by adjusting by the above adjusting method so that the pH at 25 ° C. is 5 to 13.

  In the conductive polymer solution described above, since the pH is adjusted to 5 to 13, the acidity is weak, corrosion when contacting with a metal can be prevented, and discoloration when contacting with a contact object can be prevented. Further, since the polyanion is sufficiently doped into the π-conjugated conductive polymer, conductivity is ensured.

<Conductive coating film>
The conductive coating film of the present invention is formed by applying the above-described conductive polymer paint. Examples of the method for applying the conductive polymer coating include immersion, comma coating, spray coating, roll coating, and gravure printing.
Specifically, this conductive coating film is an antistatic material such as an electronic component, an antistatic coating, an antistatic packaging material, an electromagnetic shielding material for a liquid crystal screen or a plasma display screen, a transfer belt, a developing roll, a charging roll, a transfer It is formed on the surface of an electrophotographic apparatus component such as a roll, an optical information recording medium such as a CD or DVD.
In particular, the effect of the present invention is particularly exerted when formed on an electronic component or packaging material that is weak against acid. That is, even if a conductive coating film is formed on the electronic component, corrosion of the metal or metal compound constituting the electronic component can be prevented. Specifically, in a functional capacitor having an anode made of a valve metal such as aluminum or tantalum and a dielectric layer made of an oxide obtained by electrolytic oxidation of the valve metal, the conductive layer of the present invention is formed on the dielectric layer. By forming the conductive coating film as the cathode, corrosion of the dielectric layer can be prevented. Therefore, the leakage current of the capacitor can be reduced. Moreover, when the electroconductive coating film of this invention is formed on a packaging plastic film, discoloration of what is packaged (contacted) by it can be prevented.

Example 1
(1) Preparation of polystyrene sulfonic acid solution 50 g of sodium styrene sulfonate was dissolved in 500 ml of water, 0.15 g of ammonium persulfate was added as a polymerization initiator, and polymerization was performed at 70 ° C. for 5 hours. After completion of the polymerization, 30 g of a 30% aqueous sulfuric acid solution was added, 15,000 ml of water was further added, and the solution was concentrated to 300 ml by ultrafiltration to obtain a polystyrene sulfonic acid solution.

(2) Preparation of conductive polymer solution To 100 g of the polystyrenesulfonic acid solution obtained in (1), 30 g of 3,4-ethylenedioxythiophene was added and stirred for 1 hour while cooling to 10 ° C. To this solution, an oxidant solution in which 250 g of ferric chloride was dissolved in 1250 ml of water was added dropwise over 2 hours while maintaining the temperature at 10 ° C., and stirring was further continued for 12 hours. Oxythiophene was polymerized.
After the completion of the polymerization, the obtained reaction solution was ultrafiltered to remove the oxidant residue, unreacted monomers and oligomer components, and a solution having a concentration of 1% by mass was obtained. And 100 mass parts 2-methylimidazole was added with respect to 100 mass parts of solid content of this solution, and it stirred for 1 hour, and obtained the conductive polymer solution.

About the obtained conductive polymer solution, surface resistance, pH, and metal corrosivity were measured and evaluated according to the following method. The evaluation results are shown in Table 1.
(A) Surface resistance The obtained conductive polymer solution is applied to a PET film having a thickness of 100 μm and dried to form a conductive film having a thickness of 2 μm. It was measured by.
(B) pH
The pH of the obtained conductive polymer solution was measured with a commercially available pH meter (pH meter F-22 manufactured by Horiba, Ltd.) in a constant temperature room at 25 ° C. For calibration of the pH meter, phthalic acid pH standard solution (pH 4.01), neutral phosphate pH standard solution (pH 6.86), borate pH standard solution (pH 9.18) manufactured by Kanto Chemical Co., Ltd. are used. I went.
(C) Metal corrosivity 1 g of iron plate (thickness 0.5 μm) on the conductive coating formed at the time of surface resistance measurement in an environmental test tank of 85 ° C. and 85% RH, the environment of which was adjusted with pure water. ) And left for 100 hours. And the corrosion condition of the iron plate after 100 hours was confirmed visually.

(Example 2)
A conductive polymer solution was obtained in the same manner as in Example 1 except that imidazole was added instead of 2-methylimidazole. And it evaluated similarly to Example 1. FIG. The evaluation results are shown in Table 1.

(Example 3)
A conductive polymer solution was obtained in the same manner as in Example 1 except that hydroxyethyl acrylate was added in place of 2-methylimidazole and then refluxed at 100 ° C. for 1 hour. And it evaluated similarly to Example 1. FIG. The evaluation results are shown in Table 1.

Example 4
(1) Preparation of polyacrylic acid solution 50 g of sodium acrylate was dissolved in 500 ml of water, 0.15 g of ammonium persulfate was added as a polymerization initiator, and polymerization was carried out at 70 ° C. for 5 hours. After completion of the polymerization, 30 g of a 30% aqueous sulfuric acid solution was added, 15,000 ml of water was further added, and the solution was concentrated to 300 ml by ultrafiltration to obtain a polystyrene sulfonic acid solution.

(2) Preparation of conductive polymer solution 30 g of 3,4-ethylenedioxythiophene was added to 100 g of the polyacrylic acid solution obtained in (1) and stirred for 1 hour while cooling to 10 ° C. To this solution, an oxidant solution in which 250 g of ferric chloride was dissolved in 1250 ml of water was added dropwise over 2 hours while maintaining the temperature at 10 ° C., and stirring was further continued for 12 hours. Oxythiophene was polymerized.
After the completion of the polymerization, the obtained reaction solution was ultrafiltered to remove the oxidant residue, unreacted monomers and oligomer components, and a solution having a concentration of 1% by mass was obtained. And 100 mass parts pyridine was added with respect to 100 mass parts of solid content of this solution, and it recirculate | refluxed at 100 degreeC for 1 hour, and obtained the conductive polymer solution.

(Example 5)
A conductive polymer solution was obtained in the same manner as in Example 1 except that diethylamine was added instead of 2-methylimidazole. And it evaluated similarly to Example 1. FIG. The evaluation results are shown in Table 1.

(Comparative Example 1)
In Example 1, after completion of polymerization, a solution having a concentration of 1% by mass obtained by ultrafiltration of the obtained reaction solution was used as a conductive polymer solution, and the same procedure as in Example 1 was carried out except that the pH was not adjusted. And evaluated.

The conductive coating film formed from the conductive polymer solution of Examples 1 to 5 having a pH in the range of 5 to 13 did not have impaired surface resistance and was excellent in metal corrosivity.
In contrast, the conductive coating film formed from the conductive polymer solution of Comparative Example 1 having a pH of less than 5 caused red rust on the iron plate in contact therewith.

Claims (3)

In a conductive polymer solution containing a π-conjugated conductive polymer, a polyanion, a nitrogen-containing aromatic cyclic compound, and a solvent,
The π-conjugated conductive polymer is selected from polypyrrole, polythiophene, poly (N-methylpyrrole), poly (3-methylthiophene), poly (3-methoxythiophene), and poly (3,4-ethylenedioxythiophene) (Co) polymer consisting of one or two kinds of
The polyanion is selected from polystyrene sulfonic acid, polyisoprene sulfonic acid, polyacrylic acid ethyl sulfonic acid, polybutyl acrylate sulfonic acid,
Nitrogen-containing aromatic cyclic compounds include pyridines and derivatives thereof containing one nitrogen atom, imidazoles and derivatives thereof containing two nitrogen atoms, pyrimidines and derivatives thereof, pyrazines and derivatives thereof, Selected from triazines containing nitrogen atoms and derivatives thereof,
A conductive polymer solution having a pH of 7 to 11 at a temperature of 25 ° C.   The conductive polymer solution according to claim 1, further comprising a compound having at least one of a hydroxyl group, a glycidyl group, and an amino group in the molecule.   A conductive coating film formed by applying the conductive polymer solution according to claim 1.