JP5244361B2 - Resistive touch panel - Google Patents

Description

  The present invention relates to a conductive polymer solution for forming a conductive film for a transparent electrode and a conductive film suitable as a transparent electrode for an input device. Furthermore, the present invention relates to an input device such as a touch panel.

The touch panel is an input device installed on the image display device, and at least a portion overlapping the image display device is transparent.
As the touch panel, for example, a resistance film type touch panel is known. In a resistive touch panel, a fixed electrode sheet and a movable electrode sheet in which a transparent electrode is formed on one side of a transparent substrate are arranged so that the transparent electrodes face each other. As a transparent electrode of an electrode sheet, an indium-doped tin oxide film (hereinafter referred to as ITO film) has been widely used.
A sheet having an ITO film formed on one side of a transparent substrate (hereinafter referred to as an ITO film-forming sheet) is suitable as a fixed electrode sheet on the image display device side because of its low flexibility and easy fixing. However, when used as a movable electrode sheet on the input side of the touch panel, there is a problem that durability when repeatedly flexing is low.
Therefore, as a movable electrode sheet on the input side of the touch panel, a flexible sheet in which a conductive coating film containing a π-conjugated conductive polymer is formed on one side of a transparent substrate (hereinafter referred to as a conductive polymer). Sometimes referred to as a film-forming sheet).
However, when an ITO film forming sheet is used as the fixed electrode sheet on the image display device side and a conductive polymer film forming sheet is used as the movable electrode sheet on the input side of the touch panel, that is, when different conductors are connected to each other. The contact resistance is large, and problems such as a decrease in input sensitivity and a delay in coordinate input time may occur.
In order to solve these problems, Patent Document 1 proposes adding metal ions to a conductive coating film containing a π-conjugated conductive polymer.
It is also conceivable to add metal particles to a conductive coating film containing a π-conjugated conductive polymer. Examples of electrode sheets obtained by adding metal particles to a conductive coating film containing a π-conjugated conductive polymer are disclosed in Patent Documents 2 and 3, for example.
JP 2007-172984 A JP 2005-327910 A JP 2007-080541 A

However, in the electrode sheet described in Patent Document 1, the contact resistance to the ITO film has not been sufficiently reduced.
In addition, the electrode sheets described in Patent Documents 2 and 3 are not necessarily suitable for touch panels because the transparency may be low and the contact resistance may be unevenly reduced.
Therefore, when the electrode sheets described in Patent Documents 1 to 3 are applied to a resistive film type touch panel, the visibility of the image of the image display device is lowered or the input sensitivity is lowered when installed on the image display device. In addition, there may be a delay in coordinate input time.

In addition, as a touch panel, a capacitive touch panel is also known, but even when the electrode sheet described in Patent Documents 1 to 3 is applied to the transparent electrode, the image visibility becomes low or the operation is poor. There was also a cause.
Therefore, the electrode sheets described in Patent Documents 1 to 3 are not suitable for touch panels.

This invention is made in view of the said situation, and it aims at providing the conductive polymer solution which can form the conductive coating film suitable as a transparent electrode of the electrode sheet for touch panels while being excellent in transparency. To do.
Moreover, it aims at providing the electroconductive coating film suitable as a transparent electrode of the electrode sheet for touch panels while being excellent in transparency.
It is another object of the present invention to provide an input device that has excellent image visibility when installed on an image display device and prevents malfunction.

The present invention includes the following aspects.
[1] Two transparent electrodes are provided, and one of the two transparent electrodes is an electrode formed by applying a conductive polymer solution for manufacturing a resistive touch panel, and the other transparent electrode is An electrode made of an ITO film, wherein the conductive polymer solution for manufacturing a resistive film type touch panel contains a π-conjugated conductive polymer, a polyanion, a conductive carbon black, a surfactant, and a solvent. resistive touch panels, wherein the amount of black is 0.01 to 10 mass% when the total number of the π-conjugated conductive polymer and the polyanion is 100 mass%.
[2] Resistive touch panel according to the conductive carbon black is characterized in that it is a furnace black [1].
[3] (meth) resistive touch panel having the constitution one or further containing both acrylamide compound and a polyfunctional acrylic compound [1] or [2].
[4] The total light transmittance of the electrode formed by applying the conductive polymer solution for manufacturing the resistive film type touch panel is 78% or more, and the value of (contact resistance / surface resistance to the ITO film ) is 2 or less. resistive touch panel according to any one of [1] to [3], wherein the.

According to the conductive polymer solution of the present invention, it is possible to form a conductive coating film that is excellent in transparency and suitable as a transparent electrode of an electrode sheet for a touch panel.
The conductive coating film of the present invention is excellent in transparency and suitable as a transparent electrode for an electrode sheet for a touch panel.
The input device of the present invention has excellent image visibility of the image display device when installed on the image display device, and prevents malfunction.

<Conductive polymer solution>
The π-conjugated conductive polymer of the present invention, a polyanion, conductive carbon black, and a solvent are contained.

(Π-conjugated conductive polymer)
The π-conjugated conductive polymer is not particularly limited as long as the main chain is an organic polymer composed of a π-conjugated system. For example, polypyrroles, polythiophenes, polyacetylenes, polyphenylenes, polyphenylene vinylenes, Examples thereof include polyanilines, polyacenes, polythiophene vinylenes, and copolymers thereof. From the viewpoint of stability in air, polypyrroles, polythiophenes and polyanilines are preferred.
Even if the π-conjugated conductive polymer remains unsubstituted, sufficient conductivity and compatibility with the binder resin can be obtained, but in order to further improve conductivity and compatibility, an alkyl group, a carboxy group, It is preferable to introduce a functional group such as a sulfo group, an alkoxy group, or a hydroxy group into the π-conjugated conductive polymer.

  Specific examples of the π-conjugated conductive polymer 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-methyl) -4-hexyloxypyrrole), poly (thiophene), poly (3-methylthiophene), poly (3-ethylthiophene), poly (3-propylthiophene), poly (3-butylthiophene), poly (3-hexyl) Thiophene), 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-dibutyl) Thiophene), 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), poly (3-octadecyloxythiophene), poly (3-methyl-4-methoxythiophene), poly (3,4-ethylenedioxythiophene), poly (3-methyl-4-ethoxy) Thiophene), poly (3-carboxythiophene), poly (3-methyl-4-carboxythiophene), poly (3-methyl-4-carboxyethylthiophene), poly (3-methyl-4-carboxybutylthiophene), polyaniline , Poly (2-methylaniline), poly (3-isobutyla) Phosphorus), poly (2-aniline sulfonic acid), poly (3-aniline sulfonic acid), and the like. Among them, poly (3,4-ethylenedioxythiophene) is preferable from the viewpoint of conductivity and heat resistance.

(Polyanion)
Examples of the polyanion include a substituted or unsubstituted polyalkylene, a substituted or unsubstituted polyalkenylene, a substituted or unsubstituted polyimide, a substituted or unsubstituted polyamide, and a substituted or unsubstituted polyester having an anionic group. Examples thereof include a polymer composed only of a structural unit, and a polymer composed of a structural unit having an anionic group and a structural unit not having an anionic group.

A polyalkylene is a polymer whose main chain is composed of repeating methylenes.
Polyalkenylene is a polymer composed of structural units containing one unsaturated double bond (vinyl group) in the main chain.
As polyimide, pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, benzophenonetetracarboxylic dianhydride, 2,2 ′-[4,4′-di (dicarboxyphenyloxy) phenyl] propane dianhydride And polyimides from acid anhydrides such as oxydiamine, paraphenylenediamine, metaphenylenediamine, benzophenonediamine and the like.
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 an organic 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.

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. It is done.
Examples of the hydroxy group include a hydroxy group bonded directly or via another functional group to the main chain of the polyanion. Examples of the other functional group include an alkyl group having 1 to 7 carbon atoms and an alkyl group having 2 to 7 carbon atoms. An alkenyl group, an amide group, an imide group, etc. are mentioned. Hydroxy groups are substituted at the ends or in these functional groups.
Examples of the amino group include an amino group bonded to the main chain of the polyanion directly or via another functional group. Examples of the other functional group include an alkyl group having 1 to 7 carbon atoms and an alkyl group having 2 to 7 carbon atoms. An alkenyl group, an amide group, an imide group, etc. are mentioned. The amino group is substituted at the end or in these functional groups.
Examples of the phenol group include a phenol group bonded directly or via another functional group to the main chain of the polyanion. Examples of the other functional group include an alkyl group having 1 to 7 carbon atoms and an alkyl group having 2 to 7 carbon atoms. An alkenyl group, an amide group, an imide group, etc. are mentioned. The phenol group is substituted at the end or in these functional groups.

Examples of the polyalkylene having a substituent include polyethylene, polypropylene, polybutene, polypentene, polyhexene, polyvinyl alcohol, polyvinylphenol, poly (3,3,3-trifluoropropylene), polyacrylonitrile, polyacrylate, polystyrene and the like. it can.
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-propyl-2-pentenylene, 4- Tyl-2-pentenylene, 4-hexyl-2-pentenylene, 4-cyano-2-pentenylene, 3-methyl-2-pentenylene, 4-ethyl-2-pentenylene, 3-phenyl-2-pentenylene, 4-hydroxy- Examples thereof include polymers containing one or more structural units selected from 2-pentenylene, hexenylene and the like.

Examples of the anion group of the _{^{polyanion, -O-SO 3 - X +}} , -SO 3 - X +, -COO - X + (. X + is the hydrogen ion in each of the formulas, represents an alkali metal ion), and the like. That is, the polyanion is a polymer acid containing a sulfo group and / or a carboxy group. Among these, from the viewpoint of doping effects on the π-conjugated conductive _{^{polymer, -SO 3 - X +, -COO}} - X + are preferable.
Moreover, it is preferable that this anion group is arrange | positioned in the principal chain of a polyanion adjacently or at fixed intervals.

  Among the polyanions, polyisoprene sulfonic acid, a copolymer containing polyisoprene sulfonic acid, a polysulfoethyl methacrylate, a copolymer containing polysulfoethyl methacrylate, and poly (4-sulfone) are preferable in view of solvent solubility and conductivity. Butyl methacrylate), copolymers containing poly (4-sulfobutyl methacrylate), polymethallyloxybenzene sulfonic acid, copolymers containing polymethallyloxybenzene sulfonic acid, polystyrene sulfonic acid, copolymer containing polystyrene sulfonic acid A coalescence or the like is preferable.

  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.

  The content of the polyanion is preferably in the range of 0.1 to 10 mol, and more preferably in the range of 1 to 7 mol, with respect to 1 mol of the π-conjugated conductive polymer. When the polyanion content is less than 0.1 mol, the doping effect on the π-conjugated conductive polymer tends to be weak, and the conductivity may be insufficient. In addition, the dispersibility and solubility in the solvent are reduced, making it difficult to obtain a uniform dispersion. On the other hand, when the polyanion content is more than 10 mol, the content of the π-conjugated conductive polymer is decreased, and it is difficult to obtain sufficient conductivity.

The polyanion is coordinated to the π-conjugated conductive polymer. Therefore, the π-conjugated conductive polymer and the polyanion form a complex.
The total content of the π-conjugated conductive polymer and the polyanion in the conductive polymer solution is 0.05 to 5% by mass, and preferably 0.5 to 4.0% by mass. If the total content of the π-conjugated conductive polymer and the polyanion is less than 0.05% by mass, sufficient conductivity may not be obtained. If the content exceeds 5% by mass, a uniform conductive coating film may be obtained. May not be obtained.

(Conductive carbon black)
Examples of the conductive carbon black include furnace black, acetylene black, and channel black. Furnace black is preferable from the viewpoint of conductivity.
Moreover, since conductive carbon black improves the dispersibility to water, what carried out the hydrophilicity by having a carboxy group on the surface is preferable.
Since carbon black has a carbon skeleton, it is excellent in stability in a humid heat environment. Moreover, since it is excellent in ultraviolet-absorbing ability, ultraviolet-ray deterioration can be prevented when a coating film contains carbon black.

  The average particle size of the conductive carbon black is preferably 0.01 to 0.5 μm. If the average particle diameter of the conductive carbon black is 0.01 μm or more, the handleability is excellent, and if it is 0.5 μm or less, the dispersibility of the conductive carbon black can be easily increased.

  The content of the conductive carbon black is 0.01 to 10% by mass and preferably 0.01 to 8.0% by mass with respect to 100% by mass in total of the π-conjugated conductive polymer and the polyanion. It is especially preferable that it is 0.01-5.0 mass%. When the content of the conductive carbon black is less than 0.01 parts by mass, the contact resistance in the different conductor contact may not be sufficiently lowered and may cause a malfunction. When the content exceeds 10% by mass, the conductive polymer The transparency of the conductive coating film formed from the solution may be lowered.

The conductive polymer solution preferably contains a surfactant in order to improve the dispersibility of the conductive carbon black.
As the surfactant, for example, a nonionic surfactant, an anionic surfactant, a cationic surfactant, or the like can be used.
Nonionic surfactants include, for example, higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, high alcohol fatty acid ester ethylene oxide adducts, fatty acid amide ethylene oxide adducts, and fat and oil ethylene oxide adducts. , Polyethylene glycol type nonionic surfactants such as polypropylene glycol ethylene oxide adduct, fatty acid ester of glycerol, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, fatty acid ester of sucrose, alkyl ether of polyhydric alcohol, And polyhydric alcohol type nonionic surfactants such as fatty acid amides of alkanolamines.
Examples of anionic surfactants include sulfate ester salts, sulfonate salts, phosphate esters, and soaps. Specific examples include sodium dodecylbenzenesulfonate, sodium dodecylsulfate, sodium alkylnaphthalenesulfonate, and sodium dialkylsulfosuccinate.
Examples of the cationic surfactant include amine salt type and quaternary ammonium salt type. Specific examples include alkylbenzene dimethyl ammonium chloride, certain kill trimethyl ammonium chloride, distearyl ammonium chloride and the like.

When the conductive polymer solution contains a surfactant, it is preferable to contain a neutralizing agent that neutralizes the acidity of the polyanion in order to improve the stability of the surfactant.
Examples of the neutralizing agent include inorganic alkalis and organic alkalis.
Examples of the inorganic alkali include sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia and the like.
Examples of the organic alkali include aliphatic amines, aromatic amines, quaternary amines, and metal alkoxides.

Examples of the aliphatic amine include ethylamine, propylamine, butylamine, hexylamine, octylamine, stearylamine, diethylamine, dipropylamine, dibutylamine, dioctylamine, methylethylamine, triethylamine, tripropylamine, tributylamine and the like. It is done.
Examples of the aromatic amine include aniline, benzylamine, pyrrole, pyridine and derivatives thereof, imidazole and derivatives thereof, pyrimidine and derivatives thereof, pyrazine and derivatives thereof, triazine and derivatives thereof, and the like. Of these, pyridine and derivatives thereof, imidazole and derivatives thereof, pyrimidine and derivatives thereof, pyrazine and derivatives thereof, triazine and derivatives thereof also function as conductivity improvers.
Examples of the quaternary amine include tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, and tetraoctylammonium hydroxide.
Examples of nitrogen-containing compounds other than amines include N-methyl-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, hexamethylene phosphortriamide, N-vinylpyrrolidone, N-vinylformamide, and N-vinyl. Examples include acetamide.
Examples of the metal alkoxide include sodium alkoxide such as sodium methoxide and sodium ethoxide, potassium alkoxide, calcium alkoxide and the like.
Among the neutralizing agents, organic alkalis composed of one or more components selected from the group consisting of aliphatic amines, aromatic amines, quaternary amines, and metal alkoxides are preferable.

  The neutralizing agent is preferably contained in such an amount that the pH of the conductive polymer solution (measured at 25 ° C.) is preferably 4 to 10, more preferably 5 to 9. If the pH is less than 4, the acidity is too strong, the surfactant may be destabilized and the dispersibility of the conductive carbon black may not be improved. If it exceeds 10, the formation of the coating film becomes difficult. Even if a coating film is formed, the conductivity may decrease.

(solvent)
Although it does not restrict | limit especially as a solvent, When a surfactant is contained, an aqueous solvent is preferable.
Examples of the aqueous solvent include water, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, glycerin, propylene glycol, polyglycerin, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, Examples include alcohols such as 2,3-butanediol. These solvents may be used alone or in combination of two or more.

(Acrylic compound)
The conductive polymer solution preferably contains an acrylic compound because the film formability is improved. Here, the acrylic compounds are the following compounds (a), (b) and polyfunctional acrylic compounds.
(A) An acrylic compound having a glycidyl group (hereinafter referred to as compound (a)).
(B) An acrylic compound having one type selected from an allyl group, vinyl ether group, methacryl group, acrylic group, methacrylamide group, and acrylamide group, and a hydroxy group (hereinafter referred to as compound (b)).

Furthermore, examples of the compound (a) include the following acrylic compounds (a-1) to (a-3).
(A-1): Acrylic compound having a glycidyl group and one kind selected from an allyl group, a vinyl ether group, a methacryl group, an acrylic group, a methacrylamide group, and an acrylamide group (hereinafter referred to as compound (a-1)). .
(A-2): An acrylic compound having two or more glycidyl groups (hereinafter referred to as compound (a-2)).
(A-3): An acrylic compound having one glycidyl group, and a compound other than the compound (a-1) (hereinafter referred to as compound (a-3)).

Among the compounds (a-1), examples of the compound having a glycidyl group and an acrylic (methacrylic) group include glycidyl acrylate and glycidyl methacrylate.
Examples of the compound having a glycidyl group and an allyl group include allyl glycidyl ether, 2-methylallyl glycidyl ether, and allylphenol glycidyl ether.
Examples of the compound having a glycidyl group and a hydroxy group include 1,4-dihydroxymethylbenzene diglycidyl ether and glycerin diglycidyl ether.
Examples of the compound having a glycidyl group, a hydroxy group, and an allyl group include 3-allyl-1,4-dihydroxymethylbenzene diglycidyl ether.
A compound having a glycidyl group and a hydroxy group, and a compound having a glycidyl group, a hydroxy group, and an allyl group are also compounds (b).

  Examples of the compound (a-2) include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, bisphenol A diglycidyl ether, and polyethylene glycol diglycidyl ether. , Propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, dimer acid diglycidyl ester, diglycidyl phthalate, triglycidyl isocyanurate, tetraglycidyl diaminodiphenylmethane, diglycidyl tetraphthalate, etc. Or it can be used as a mixture of two or more.

  Examples of the compound (a-3) include alkyl glycidyl ether, ethylene glycol glycidyl ether, methyl glycidyl ether, phenyl glycidyl ether, butylphenyl glycidyl ether, and cresyl glycidyl ether.

Among the compounds (b), examples of the compound having a hydroxy group and a vinyl ether group include 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, and the like.
As a compound having a hydroxy group and an acrylic (methacrylic) group, 2-hydroxyethyl acrylate (methacrylate), 2-hydroxypropyl acrylate (methacrylate), 4-hydroxybutyl acrylate (methacrylate), ethyl-α-hydroxymethyl acrylate, dipenta Erythritol monohydroxypentaacrylate etc. are mentioned.
Examples of the compound having a hydroxy group and an acrylamide (methacrylamide) group include 2-hydroxyethyl acrylamide and 2-hydroxyethyl methacrylamide.

In the compound (a), the glycidyl group reacts with the remaining anion group (eg, sulfo group, carboxy group, etc.) of the polyanion to form an ester (eg, sulfonate ester, carboxylate ester, etc.). In the reaction, the reaction may be promoted by a basic catalyst, pressurization, or heating. During ester formation, the glycidyl group opens to form a hydroxy group. This hydroxy group causes a dehydration reaction with the remaining anionic group that did not form a salt or ester with the conductive polymer to form a new ester (for example, a sulfonic acid ester, a carboxylic acid ester, etc.). By forming such an ester, the complex of the polyanion and the conductive polymer is cross-linked.
Furthermore, in the compound (a-1), after the residual anion group of the polyanion is bonded to the glycidyl group of the compound (a-1), the allyl group, vinyl ether group, methacryl group, acrylic group of the compound (a-1) is bonded. Groups, methacrylamide groups, and acrylamide groups are polymerized to further crosslink the composites.

  In the compound (b), the hydroxy group dehydrates with the remaining anion group of the polyanion dopant to form an ester. In the dehydration reaction, the reaction may be promoted by an acidic catalyst. Thereafter, the allyl group, vinyl ether group, methacryl group, acrylic group, methacrylamide group, and acrylamide group of the compound (b) are polymerized. By this polymerization, the complex of the polyanion and the conductive polymer is cross-linked.

  Examples of (meth) acrylamide compounds include 2-hydroxyethyl acrylamide, 2-hydroxyethyl methacrylamide, and the like. The polymer of the (meth) acrylamide compound has good compatibility with the complex of the π-conjugated conductive polymer and the polyanion, and can further improve the conductivity.

The polyfunctional acrylic compound is an acrylic compound having two or more unsaturated double bonds. When the polyfunctional acrylic compound is contained, the complex of the π-conjugated conductive polymer and the polyanion is easily crosslinked at the time of forming the coating film, and the conductivity and the coating film strength are improved.
Specific examples of the polyfunctional acrylic compound include dipropylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tripropylene glycol di (meth) acrylate, modified bisphenol A di (meth) acrylate, di Methylol dicyclopentadi (meth) acrylate, polyethylene glycol (hereinafter referred to as PEG) 400 di (meth) acrylate, PEG300 di (meth) acrylate, PEG600 di (meth) acrylate, N, N′-methylenebisacrylamide Bifunctional acrylic monomers such as trimethylolpropane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, glycerin propoxytri ( Trifunctional acrylic monomers such as (meth) acrylate, pentaerythritol tri (meth) acrylate, ethoxylated glycerin triacrylate, pentaerythritol ethoxytetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, A tetrafunctional or higher functional acrylic monomer such as dipentaerythritol hexa (penta) (meth) acrylate or dipentaerythritol monohydroxypenta (meth) acrylate, a pentafunctional or higher acrylic monomer such as sorbitol pentaacrylate or dipentaerythritol pentaacrylate, di Pentaerythritol hexaacrylate, sorbitol hexaacrylate, alkylene oxide modified hexaacrylate, Caprolactone-modified dipentaerythritol 6 or more functional acrylic monomers hexaacrylate, bifunctional or higher functional urethane acrylate.

Of the polyfunctional acrylic compounds, the polyfunctional acrylic monomer preferably has a molecular weight of 3000 or less. A polyfunctional acrylic monomer having a molecular weight exceeding 3000 has low solvent solubility. Further, since the unsaturated double bond equivalent is reduced, it is difficult to crosslink the composite, and sufficient strength cannot be obtained after the formation of the conductive coating film.
Of the polyfunctional acrylic compounds, the polyfunctional urethane acrylate preferably has a molecular weight of 1000 or less in terms of solvent solubility, wear resistance, and low shrinkage. In the polyfunctional urethane acrylate having a molecular weight exceeding 1000, the introduction rate of the urethane group formed by the isocyanate group and the polyol (hydroxyl group) decreases, and the solubility in the solvent tends to be low.

  In terms of further improving film formability, it is preferable to further contain one or both of a (meth) acrylamide compound and a polyfunctional acrylic compound.

  The content of the acrylic compound is preferably 0.05 to 50% by mass and more preferably 0.3 to 30% by mass with respect to 100% by mass in total of the π-conjugated conductive polymer and the polyanion. . When the content of the acrylic compound is less than 0.05% by mass, the film formability of the conductive polymer solution may be insufficient, and when it exceeds 50% by mass, the π-conjugated conductivity in the conductive coating film In some cases, the polymer content decreases and sufficient conductivity cannot be obtained.

In the polymerization of the acrylic compound, a radical polymerization method, a thermal polymerization method, a photo radical polymerization method, or a plasma polymerization method can be applied.
In the radical polymerization method, polymerization is performed using, for example, an azo compound such as azobisisobutyronitrile, a peroxide such as benzoyl peroxide, diacyl peroxides, peroxyesters, and hydroperoxides as a polymerization initiator.
In the photo radical polymerization method, polymerization is performed using a carbonyl compound, a sulfur compound, an organic peroxide, an azo compound, or the like as a polymerization initiator. Specifically, benzophenone, Michler's ketone, xanthone, thioxanthone, 2-ethylanthraquinone, acetophenone, trichloroacetophenone, 2-hydroxy-2-methyl-propiophenone, 1-hydroxycyclohexyl phenyl ketone, benzoin ether, 2,2-di Ethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, benzyl, methylbenzoylformate, 1-phenyl-1,2-propanedione-2- (o-benzoyl) oxime, 2,4,6-trimethylbenzoyldiphenyl Examples include phosphine oxide, tetramethylthiuram, dithiocarbamate, benzoyl peroxide, N-laurylpyridium azide, and polymethylphenylsilane.
In plasma polymerization, plasma is irradiated for a short time, receives energy from electron bombardment of the plasma, performs fragmentation and rearrangement, and then generates a polymer by recombination of radicals.

  Moreover, the polymerization of the vinyl ether group in the compound (a-1) and the compound (b) employs a cationic polymerization method. In cationic polymerization, Lewis acids such as metal halides and organometallic compounds are used to promote the reaction, and other electrophilic reagents that generate cations by light or heat, such as halogens, strong acid salts, and carbonium ion salts. May be.

(Polymerization initiator)
When an acrylic compound is contained, the polymerization reaction can be promoted, and therefore it is preferable that the conductive polymer solution contains a polymerization initiator such as a photopolymerization initiator or a cationic polymerization initiator.
Examples of the photopolymerization initiator include acetophenones, benzophenones, Michler benzoylbenzoate, tetramethylthiuram monosulfide, and thioxanthones. Furthermore, n-butylamine, triethylamine, tri-n-butylphosphine, or the like can be mixed as a photosensitizer.
Examples of the cationic polymerization initiator include aryldiazonium salts, diarylhalonium salts, triphenylsulfonium salts, silanol / aluminum chelates, α-sulfonyloxyketones, and the like.

(Aromatic compounds having two or more hydroxy groups)
Moreover, since the electroconductivity polymer solution becomes higher in electroconductivity of the electroconductive coating film obtained, it is preferable to contain the aromatic compound which has a 2 or more hydroxy group.
Examples of aromatic compounds having two or more hydroxy groups include 1,4-dihydroxybenzene, 1,3-dihydroxybenzene, 2,3-dihydroxy-1-pentadecylbenzene, 2,4-dihydroxyacetophenone, 2,5 -Dihydroxyacetophenone, 2,4-dihydroxybenzophenone, 2,6-dihydroxybenzophenone, 3,4-dihydroxybenzophenone, 3,5-dihydroxybenzophenone, 2,4'-dihydroxydiphenylsulfone, 2,2 ', 5,5' -Tetrahydroxydiphenylsulfone, 3,3 ', 5,5'-tetramethyl-4,4'-dihydroxydiphenylsulfone, hydroxyquinone carboxylic acid and its salts, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid Acid, 2,5-dihydroxy Benzoic acid, 2,6-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 1,4-hydroquinonesulfonic acid and its salts, 4,5-hydroxybenzene-1,3-disulfonic acid and its salts, 1,5 -Dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,5-dihydroxynaphthalene-2,6-dicarboxylic acid, 1,6- Dihydroxynaphthalene-2,5-dicarboxylic acid, 1,5-dihydroxynaphthoic acid, 1,4-dihydroxy-2-naphthoic acid phenyl ester, 4,5-dihydroxynaphthalene-2,7-disulfonic acid and salts thereof, 1, 8-dihydroxy-3,6-naphthalenedisulfonic acid and its salts, 6 7-dihydroxy-2-naphthalenesulfonic acid and its salts, 1,2,3-trihydroxybenzene (pyrogallol), 1,2,4-trihydroxybenzene, 5-methyl-1,2,3-trihydroxybenzene, 5-ethyl-1,2,3-trihydroxybenzene, 5-propyl-1,2,3-trihydroxybenzene, trihydroxybenzoic acid, trihydroxyacetophenone, trihydroxybenzophenone, trihydroxybenzaldehyde, trihydroxyanthraquinone, Examples include 2,4,6-trihydroxybenzene, tetrahydroxy-p-benzoquinone, tetrahydroxyanthraquinone, methyl garlic acid (methyl gallate), and ethyl garlic acid (ethyl gallate).

  The content of the aromatic compound having two or more hydroxy groups is preferably in the range of 0.05 to 50 mol, more preferably in the range of 0.3 to 10 mol with respect to 1 mol of the anion group unit of the polyanion. It is more preferable. If the content of the aromatic compound having two or more hydroxy groups is less than 0.05 mol relative to 1 mol of the anion group unit of the polyanion, the conductivity may not be increased. In addition, when the content of the compound having two or more hydroxy groups is more than 50 mol with respect to 1 mol of the anion group unit of the polyanion, the content of the π-conjugated conductive polymer in the conductive coating film is small. As a result, sufficient conductivity may not be obtained.

(Additive)
The conductive polymer solution may contain an additive as necessary.
The additive is not particularly limited as long as it can be mixed with a π-conjugated conductive polymer and a polyanion. For example, an antifoaming agent, a coupling agent, an antioxidant, an ultraviolet absorber, and the like can be used.
Examples of the antifoaming agent include silicone resin, polydimethylsiloxane, and silicone resin.
Examples of the coupling agent include silane coupling agents having a vinyl group, an amino group, an epoxy group, and the like.
Examples of the antioxidant include phenolic antioxidants, amine antioxidants, phosphorus antioxidants, sulfur antioxidants, saccharides, vitamins and the like.
Examples of UV absorbers include benzotriazole UV absorbers, benzophenone UV absorbers, salicylate UV absorbers, cyanoacrylate UV absorbers, oxanilide UV absorbers, hindered amine UV absorbers, and benzoate UV absorbers. Is mentioned.
It is preferable to use an antioxidant and an ultraviolet absorber in combination.

(Method for producing conductive polymer solution)
As a method for producing a conductive polymer solution, for example, a precursor polymer of a π-conjugated conductive polymer is chemically oxidatively polymerized in an aqueous solution of polyanion to prepare a conductive polymer aqueous solution, and conductive carbon is added to the aqueous solution. It can be prepared by adding black and optional components such as a surfactant and a neutralizing agent as required.
Here, since conductive carbon black improves dispersibility, it is preferable to add in the state emulsified with surfactant.
The neutralizing agent is preferably added after other components other than the neutralizing agent constituting the conductive polymer solution are added in that neutralization can be performed with high accuracy. That is, it is preferable to add the neutralizing agent last. However, when it is desired to simplify the addition operation, it is preferable to add the neutralizing agent and other components simultaneously.

According to the conductive polymer solution of the present invention containing conductive carbon black, a conductive coating film containing conductive carbon black, having high conductivity and low contact resistance with respect to the ITO film can be formed.
Moreover, since the content of the conductive carbon black is at most 10% by mass with respect to the total of 100% by mass of the π-conjugated conductive polymer and the polyanion, the resulting conductive coating film has high transparency.

<Conductive coating film>
The conductive coating film of the present invention is formed by applying the conductive polymer solution on a transparent substrate. This conductive coating film contains π-conjugated conductive polymer, polyanion, and conductive carbon black as essential components.

  As a method for applying the conductive polymer solution, for example, comma coating, reverse coating, lip coating, micro gravure coating, or the like is applied.

  Examples of the transparent substrate to which the conductive polymer solution is applied include, for example, polyethylene terephthalate (PET), polyethylene naphthalate, polyethersulfone, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, Examples thereof include films or sheets of cellulose triacetate and cellulose acetate propionate. Moreover, a glass substrate, a silicon substrate, etc. can also be used.

It is preferable to perform a curing treatment after the application of the conductive polymer solution.
As the curing method, heating or light irradiation is applied. As a heating method, for example, a normal method such as hot air heating or infrared heating can be employed. Moreover, when hardening by light irradiation, the method of irradiating an ultraviolet-ray from light sources, such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, a metal halide lamp, can be employ | adopted, for example.
The illuminance upon UV irradiation is preferably 100 mW / cm ² . Since the reducing agent may inhibit the polymerization of the acrylic compound, if the illuminance is less than 100 mW / cm ² , it does not sufficiently crosslink, and the sliding resistance (durability) of the conductive coating tends to decrease. is there. In addition, the illumination intensity in this invention is the value measured using Topcon Co., Ltd. UVR-T1 (Industrial UV checker, light receiver; UD-T36, measurement wavelength range; 300-390 nm, peak sensitivity wavelength; about 355 nm). .

The conductive coating film of the present invention is formed from the above-described conductive polymer solution, and contains conductive carbon black in addition to the π-conjugated conductive polymer and polyanion. Low contact resistance to the membrane.
Further, in the conductive coating film of the present invention, the conductive carbon black is dispersed with high dispersibility, and the content of the conductive carbon black is at most 100% by mass in total of the π-conjugated conductive polymer and the polyanion. Therefore, the transparency of the conductive coating film is high.

  The conductive coating film of the present invention is suitably used for, for example, an input device described later, but may be used as a transparent electrode of a display device. Examples of the display device include an electroluminescence display and a liquid crystal display.

<Input device>
The input device of the present invention includes the conductive coating film as a transparent electrode. Among the input devices, the resistive touch panel is preferable because the effects of the present invention are particularly exhibited. Hereinafter, an example of a resistive film type touch panel provided with the conductive coating film as a transparent electrode will be described.
As shown in FIG. 1, the resistive touch panel of this example has the above-mentioned conductive coating film 12 formed on the surface of the transparent substrate 11, the movable electrode sheet 10 disposed on the input side, and the surface of the transparent substrate 21. The ITO film 22 is formed on the fixed electrode sheet 20 arranged on the image display device side so that the conductive coating film 12 and the ITO film 22 face each other. A transparent dot spacer 24 is disposed between the movable electrode sheet 10 and the fixed electrode sheet 20 to form a gap.

  Examples of the transparent base materials 11 and 21 of the movable electrode sheet 10 or the fixed electrode sheet 20 include a single layer or two or more layers of plastic films, glass plates, and laminates of films and glass plates. However, since the transparent base material 11 of the movable electrode sheet 10 is flexible, a plastic film is preferable, and the transparent base material 21 of the fixed electrode sheet 20 is easily fixed, and thus a glass plate is used. Those are preferred.

The thickness of the transparent substrate 11 of the movable electrode sheet 10 is preferably 100 to 250 μm. If the thickness of the transparent substrate 11 is 100 μm or more, sufficient strength can be secured, and if it is 250 μm or less, sufficient flexibility can be secured.
The thickness of the conductive coating film 12 of the movable electrode sheet 10 is preferably 50 to 700 μm. If the thickness of the transparent substrate 11 is 50 μm or more, sufficient conductivity can be secured, and if it is 700 μm or less, sufficient flexibility and transparency can be secured.
The thickness of the transparent substrate 21 of the fixed electrode sheet 20 is preferably 0.8 to 2.5 mm. If the thickness of the transparent substrate 11 is 0.8 mm or more, sufficient strength can be ensured, and if it is 2.5 mm or less, the thickness can be reduced and space saving can be realized.
The thickness of the ITO film 22 of the fixed electrode sheet 20 is preferably 0.01 to 1.0 μm. If the thickness of the ITO film 22 is 0.01 μm or more, sufficient conductivity can be ensured, and if it is 1.0 μm or less, the thickness can be reduced and space saving can be realized.
It is preferable that the space | interval at the time of the non-pressing of the movable electrode sheet 10 and the fixed electrode sheet 20 is 20-100 micrometers. If the distance between the movable electrode sheet 10 and the fixed electrode sheet 20 when not pressed is 20 μm or more, the movable electrode sheet 10 and the fixed electrode sheet 20 can be reliably prevented from contacting each other when not pressed, and the distance is 100 μm or less. If it exists, the movable electrode sheet 10 and the fixed electrode sheet 20 can be reliably brought into contact at the time of pressing. In order to achieve the spacing, the size of the dot spacers 24 may be selected as appropriate.

In this resistive film type touch panel, when the movable electrode sheet 10 is pressed by a finger or a stylus, the conductive coating film 12 of the movable electrode sheet 10 and the ITO film 22 of the fixed electrode sheet 20 are brought into contact with each other to conduct electricity. The voltage is taken in and the position is detected.
In such a resistive touch panel, since the conductive coating film 12 is provided as a transparent electrode, the contact resistance with respect to the ITO film 22 is small, and malfunctions such as a decrease in input sensitivity and a delay in coordinate input time are unlikely to occur. Moreover, since the electroconductive coating film 12 is highly transparent, the image visibility of the image display device is excellent.

The input device may be a capacitive touch panel. As the capacitive touch panel using the conductive coating film, for example, a pair of transparent electrodes made of the conductive coating film is provided on both surfaces of the transparent substrate, and a low-voltage electric field is formed on the entire transparent electrode, Examples include detecting the position by touching with a finger to detect changes in surface charge.
In this capacitive touch panel, since the conductive film containing conductive carbon black and having high conductivity is used as the transparent electrode, it is possible to reliably detect a change in electric charge and hardly cause malfunction. In addition, since the conductive coating film is highly transparent, the image display device has excellent image visibility.

  Such an input device is provided in, for example, an electronic notebook, a personal digital assistant (PDA), a mobile phone, a PHS, an automatic teller machine (ATM), a vending machine, a point-of-sale information management (POS) register, and the like. .

Examples of the present invention will be specifically described below, but the present invention is not limited to the examples.
(Production Example 1) Preparation of polystyrene sulfonic acid 206 g of sodium styrene sulfonate was dissolved in 1000 ml of ion-exchanged water, and 1.14 g of ammonium persulfate oxidizing agent solution previously dissolved in 10 ml of water was stirred at 80 ° C. The solution was added dropwise for 20 minutes and the solution was stirred for 2 hours.
1000 ml and 10,000 ml of ion-exchanged water diluted with 10% by mass of sulfuric acid diluted to 10% by mass were added to the sodium styrenesulfonate-containing solution thus obtained, and about 10,000 ml of the polystyrenesulfonic acid-containing solution was removed using an ultrafiltration method. Then, 10,000 ml of ion-exchanged water was added to the remaining liquid, and about 10,000 ml of solution was removed using an ultrafiltration method. The above ultrafiltration operation was repeated three times.
Furthermore, about 10,000 ml of ion-exchanged water was added to the obtained filtrate, and about 10,000 ml of solution was removed using an ultrafiltration method. This ultrafiltration operation was repeated three times.
The ultrafiltration conditions were as follows (the same applies to other examples).
Molecular weight cut off of ultrafiltration membrane: 30000
Cross flow type Supply liquid flow rate: 3000 ml / min Membrane partial pressure: 0.12 Pa
Water in the obtained solution was removed under reduced pressure to obtain colorless solid polystyrene sulfonic acid.

(Production Example 2) Preparation of Polystyrenesulfonic Acid Doped Poly (3,4-ethylenedioxythiophene) Aqueous Solution 14.2 g of 3,4-ethylenedioxythiophene and 36.7 g of polystyrenesulfonic acid obtained in Production Example 1 A solution dissolved in 2000 ml of ion-exchanged water was mixed at 20 ° C.
While maintaining the mixed solution thus obtained at 20 ° C. and stirring, 29.64 g of ammonium persulfate dissolved in 200 ml of ion exchange water and 8.0 g of ferric sulfate oxidation catalyst solution were slowly added, The reaction was stirred for 3 hours.
2000 ml of ion-exchanged water was added to the resulting reaction solution, and about 2000 ml of solution was removed using an ultrafiltration method. This operation was repeated three times.
Then, 200 ml of sulfuric acid diluted to 10% by mass and 2000 ml of ion-exchanged water are added to the treatment liquid that has been subjected to the filtration treatment, and about 2000 ml of the treatment liquid is removed using an ultrafiltration method. Ion exchange water was added and about 2000 ml of liquid was removed using ultrafiltration. This operation was repeated three times.
Furthermore, 2000 ml of ion-exchanged water was added to the obtained treatment liquid, and about 2000 ml of the treatment liquid was removed using an ultrafiltration method. This operation was repeated 5 times to obtain an about 1.5% by mass blue polystyrenesulfonic acid-doped poly (3,4-ethylenedioxythiophene) (PEDOT-PSS) aqueous solution.

Example 1
To 600 g of the PEDOT-PSS aqueous solution obtained in Production Example 2, 1 g of paste of ketjen black, which is furnace black (lion paste W-376R manufactured by Lion, containing nonionic surfactant, solid concentration 12.5% by mass) 1.7 mass% with respect to a total of 100 mass% of the π-conjugated conductive polymer and the polyanion) was added and stirred to prepare a PEDOT-PSS aqueous solution containing ketjen black.
Separately, 3.6 g of 2,3,3 ′, 4,4 ′, 5′-hexahydroxybenzophenone, 0.9 g of Irgacure 127 (manufactured by Ciba Specialty Chemicals), 18 g of 2-hydroxyethylacrylamide, penta 7.2 g of erythritol triacrylate and 300 g of ethanol were mixed and stirred. A PEDOT-PSS aqueous solution containing the ketjen black was added to the solution thus obtained, and dispersed with a nanomizer (manufactured by Yoshida Kikai Kogyo Co., Ltd.) to obtain a conductive polymer solution A.
The conductive polymer solution A was applied to a polyethylene terephthalate film (A4300 manufactured by Toyobo Co., Ltd., thickness: 188 μm) with a reverse coater, dried at 100 ° C. for 2 minutes by infrared irradiation, and then irradiated with ultraviolet light (high pressure mercury lamp 120 W, 360 mJ / cm ² and 178 mW / cm ² ) and cured to form a conductive coating film. The surface resistance, light transmittance, and contact resistance of the conductive coating film were measured by the following methods. The results are shown in Table 1.

[Surface resistance value]
Measurement was performed according to JIS K 7194 using a Loresta MCP-T600 manufactured by Mitsubishi Chemical Corporation.
[Light transmittance]
The light transmittance was measured according to JIS K7136 using a Nippon Denshoku Industries Co., Ltd. haze meter measuring device (NDH5000).
[Contact resistance]
A conductive polymer solution was applied on a transparent substrate (polyethylene terephthalate film, Toyobo A4300, thickness; 188 μm) 11 to form a conductive coating film 12 and cut into 40 mm × 50 mm. A conductive paste (FA-401CA manufactured by Fujikura Kasei Co., Ltd.) is screen-printed on the edges of the cut sheet on the conductive coating film 12 in the width direction and dried to form electrode wirings 13a and 13b. The movable electrode sheet 10 (see FIG. 2) was obtained.
Further, a glass plate 21 (surface resistance: 300Ω) provided with an ITO film 22 and cut to 40 mm × 50 mm was prepared. A conductive paste (XA436 manufactured by Fujikura Kasei Co., Ltd.) was screen-printed on the edge of the prepared glass plate 21 on the ITO film 22 in the longitudinal direction and dried to form electrode wirings 23a and 23b. Subsequently, a dot spacer paste (SN-8400C manufactured by Fujikura Kasei Co., Ltd.) was screen-printed on the ITO film 22, dried, and irradiated with ultraviolet rays to form dot spacers 24. Next, a resist paste (SN-8800G manufactured by Fujikura Kasei Co., Ltd.) was screen-printed on the electrode wirings 23a and 23b, dried, and irradiated with UV to form the insulating layer 25. Further, an adhesive (XB-114 manufactured by Fujikura Kasei Co., Ltd.) was screen-printed on the insulating layer 25 and dried to form an adhesive layer 26 for bonding to the movable electrode sheet 10. Thereby, the fixed electrode sheet 20 (refer FIG. 3) for image display apparatuses was obtained.
Next, as shown in FIG. 4, the movable electrode sheet 10 and the fixed electrode sheet 20 are arranged so that the conductive coating film 12 and the ITO film 22 face each other, and are bonded together by an adhesive layer 26, thereby being a resistive film type touch panel. A module was produced. In addition, one electrode wiring 23 a of the fixed electrode sheet 20 and the precision power supply 31 are connected to a pull-up resistor (82.3 kΩ) 32 and a pull-up resistor 32 in parallel with a voltage measurement tester 33 for the pull-up resistor 32. Electrically connected. Further, the precision power supply 31 and one electrode wiring 13a of the movable electrode sheet 20 were electrically connected. In addition, the other electrode wiring 13b of the movable electrode sheet 10 and the other electrode wiring 23b of the fixed electrode sheet 20 were electrically connected via a voltage measurement tester 34 of a resistive film type touch panel module. Thereby, an electrical circuit for contact resistance measurement was obtained.
The contact resistance was measured as follows. With a polyacetal stylus 35 with a tip of 0.8R, the movable electrode sheet 10 is pressed with a load of 250 g, and the voltage of the pull-up resistor and the voltage of the resistive touch panel module when a voltage of 5 V is applied by the precision power supply 31 are measured. And contact resistance was measured from these measurement results.
Specifically, the current value flowing through the pull-up resistor 32 is calculated by substituting the measured voltage value and the pull-up resistor value into Ohm's law equation, and the calculated current value and the voltage of the resistive touch panel module are calculated. The contact resistance was obtained by substituting the value into the following equation.
Contact resistance (Ω) = [(resistance film type touch panel module voltage (V)) / (pull-up resistance voltage (V))] × pull-up resistance (Ω)
[Sliding test]
In order to measure the coating film strength of the conductive coating film, a Kimwipe (manufactured by Nippon Paper Crecia Co., Ltd.) moistened with ethanol was rubbed 30 times with a load of 100 gf / cm ² and the removal of the conductive coating film was visually observed. Inspected. Further, the contact resistance after the sliding test was measured. These results are indicators of the film strength of the conductive coating film.
◎: No peeling, ○: Slight peeling, △: Partial peeling, ×: Complete peeling

(Example 2)
To 600 g of the PEDOT-PSS aqueous solution obtained in Production Example 2, 20.1 g of imidazole (2 molar equivalents relative to the polyanion) and ketjen black paste (Lion Corporation Lion Paste W-311N, containing nonionic surfactant, solid PEDOT containing 1 g of imidazole and ketjen black was added to 4 g (partial concentration: 16.5% by mass) of 4 g (9.2% by mass with respect to the total of 100% by mass of the π-conjugated conductive polymer and polyanion). -A PSS aqueous solution was prepared.
Separately, 3.6 g of methyl garlic acid, 0.9 g of Irgacure 127 (manufactured by Ciba Specialty Chemicals), 18 g of 2-hydroxyethylacrylamide, 7.2 g of ditrimethylolpropane tetraacrylate, and 300 g of ethanol are mixed and stirred. did. A PEDOT-PSS aqueous solution containing the imidazole and ketjen black was added to the solution thus obtained, and dispersed with a nanomizer (manufactured by Yoshida Kikai Kogyo Co., Ltd.) to obtain a conductive polymer solution B. Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution B was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

(Example 3)
To 600 g of the PEDOT-PSS aqueous solution obtained in Production Example 2, 9.0 g of vinylimidazole (2 molar equivalents relative to the polyanion) and a ketjen black paste (Lion's Lion Paste W-356A, containing a cationic surfactant, (Solid content concentration: 11.5% by mass) 0.4 g (0.64% by mass with respect to the total of 100% by mass of the π-conjugated conductive polymer and polyanion) is added, stirred, and vinylimidazole and ketjen black A PEDOT-PSS aqueous solution containing ss was prepared.
Separately, 3.6 g hydroquinone, 0.9 g Irgacure 127 (manufactured by Ciba Specialty Chemicals), 18 g 2-hydroxyethylacrylamide, ethoxylated glycerin triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-GLY-6E) ) 7.2 g and 300 g of ethanol were mixed and stirred. A PEDOT-PSS aqueous solution containing the vinyl imidazole and ketjen black was added to the solution thus obtained, and dispersed with a nanomizer (manufactured by Yoshida Kikai Kogyo Co., Ltd.) to obtain a conductive polymer solution C. Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution C was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

Example 4
To 600 g of the PEDOT-PSS aqueous solution obtained in Production Example 2, 9.0 g of tetraammonium hydroxide (1.1 molar equivalents with respect to the polyanion) was added and stirred, and the aqueous solution of PEDOT-PSS containing tetraammonium hydroxide was added. Was prepared.
Moreover, 200 g of conductive ketjen black powder (manufactured by Lion Corporation, carbon ECP), 50 g of sodium dodecylbenzenesulfonate, 200 g of diethylene glycol, and 1000 g of ion-exchanged water are mixed, and an ultrasonic vibrator (high power ultrasonic wave manufactured by Alex Corporation) is mixed. The second preparation liquid was obtained by stirring using a washing machine Neonenic).
Further, 3.6 g of pyrogallol, 0.9 g of Irgacure 127 (manufactured by Ciba Specialty Chemicals), 18 g of 2-hydroxyethylacrylamide, 7.2 g of dipentaerythritol pentaacrylate, and 300 g of ethanol are mixed and stirred. A preparation solution was obtained.
To the PEDOT-PSS aqueous solution containing tetraammonium hydroxide, 0.125 g of the second preparation liquid (0.023% by mass of conductive carbon black with respect to the π-conjugated conductive polymer and polyanion) is added and stirred. Furthermore, the 3rd preparation liquid was added and the conductive polymer solution D was obtained by carrying out the dispersion process by the nanomizer (made by Yoshida Kikai Kogyo Co., Ltd.). Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution D was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

(Example 5)
200 g of conductive ketjen black powder (manufactured by Lion Corporation, carbon EC300J), 300 g of sodium dodecylbenzenesulfonate, and 1000 g of ion-exchanged water were mixed and dispersed using an ultrasonic homogenizer to obtain a first preparation solution.
Separately, 7.2 g of tannic acid, 0.9 g of Irgacure 127 (manufactured by Ciba Specialty Chemicals), 18 g of 2-hydroxyethylacrylamide, 7.2 g of tripropylene glycol diacrylate, and 300 g of ethanol are mixed and stirred. Thus, a second preparation liquid was obtained.
To 600 g of the PEDOT-PSS aqueous solution obtained in Production Example 2, 2.2 g of the first preparation liquid (0.42% by mass of conductive carbon black with respect to the π-conjugated conductive polymer and polyanion) is added and stirred. Furthermore, the 2nd preparation liquid was added, and the conductive polymer solution E was obtained by carrying out the dispersion process by the nanomizer (made by Yoshida Kikai Co., Ltd.). Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution E was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

(Example 6)
A conductive polymer solution F was obtained in the same manner as in Example 1 except that dipentaerythritol hexaacrylate was not added in Example 1. Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution F was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

(Example 7)
A conductive polymer solution G was obtained in the same manner as in Example 2 except that 20 g of dimethyl sulfoxide was added instead of 2-hydroxyethylacrylamide in Example 2 and no ditrimethylolpropane tetraacrylate was added. Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution G was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

(Example 8)
In Example 1, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the ultraviolet irradiation condition was changed to a high-pressure mercury lamp 100W, 360 mJ / cm ² , and 89 mW / cm ² . The evaluation results are shown in Table 1.

(Comparative Example 1)
Except that the amount of ketjen black paste added in Example 3 was changed to 0.004 g (the conductive carbon black was 0.0064% by mass with respect to the total of 100% by mass of the π-conjugated conductive polymer and the polyanion). In the same manner as in Example 3, a conductive polymer solution H was obtained. Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution H was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

(Comparative Example 2)
Example 4 except that the amount of the second preparation liquid added in Example 4 was changed to 4 g (the conductive carbon black was 11.1% by mass with respect to the total of 100% by mass of the π-conjugated conductive polymer and the polyanion). In the same manner as above, a conductive polymer solution I was obtained. Then, a conductive coating film was formed and evaluated in the same manner as in Example 1 except that the conductive polymer solution I was used instead of the conductive polymer solution A. The evaluation results are shown in Table 1.

According to the conductive polymer solutions of Examples 1 to 7 including the π-conjugated conductive polymer, polyanion, and conductive carbon black, the conductive coating having excellent conductivity and transparency and low contact resistance to the ITO film. A film could be formed.
Furthermore, since the conductive polymer solutions of Examples 1 to 5 contained a polyfunctional acrylic compound, the conductive coating obtained thereby had film strength, adhesion of the conductive coating to the transparent substrate, The adhesion of conductive carbon black was also excellent. In Example 8, the polyfunctional acrylic compound was included, but the film strength was low because the illuminance of ultraviolet rays at the time of coating film formation was less than 100 mW / cm ² .

Conductivity formed by the conductive polymer solution of Comparative Example 1 containing a π-conjugated conductive polymer, polyanion, and conductive carbon black, but the amount of conductive carbon black added was less than 0.01% by mass. The coating film had a large contact resistance with respect to the ITO film, and was not suitable for input devices.
A conductive coating film formed from the conductive polymer solution of Comparative Example 2 containing a π-conjugated conductive polymer, a polyanion, and conductive carbon black, but the amount of conductive carbon black added exceeded 10% by mass. However, sufficient transparency was not obtained, and it was not suitable for an input device.

It is sectional drawing which shows an example of the input device of this invention. It is sectional drawing which shows the electrode sheet by the side of an input person in the measuring method of contact resistance. It is sectional drawing which shows the electrode sheet by the side of the image display apparatus in the measuring method of contact resistance. It is a schematic diagram which shows the circuit in the measuring method of contact resistance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Movable electrode sheet 11 Transparent base material 12 Conductive coating film 13 Electrode wiring 20 Fixed electrode sheet 21 Transparent base material 22 ITO film 23 Electrode wiring 24 Dot spacer

Claims (4)

Two transparent electrodes are provided, and one of the two transparent electrodes is an electrode formed by applying a conductive polymer solution for manufacturing a resistive touch panel, and the other transparent electrode is made of an ITO film. An electrode,
The conductive polymer solution for producing a resistive touch panel includes a π-conjugated conductive polymer, a polyanion, a conductive carbon black, a surfactant, and a solvent, and the conductive carbon black content is π-conjugated. resistive touch panels, characterized in that from 0.01 to 10% by weight when the total of the system conductive polymer and polyanion is 100 mass%. Resistive touch panel according to claim 1 in which the conductive carbon black is characterized in that it is a furnace black. (Meth) resistive touch panel according to claim 1 or 2, characterized in one or further containing both acrylamide compound and a polyfunctional acrylic compound. The total light transmittance of the electrode formed by applying the conductive polymer solution for manufacturing the resistive film type touch panel is 78% or more, and the value of (contact resistance / surface resistance to the ITO film ) is 2 or less. resistive touch panel according to any one of claims 1 to 3.

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