JP2017200995A - Method for producing conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a conductive film, capable of suppressing a decrease in conductivity of a conductive film when forming the conductive film by stretching a coating layer formed using a coating liquid containing a conductive polymer.SOLUTION: The method for producing a conductive film includes the steps of: preparing a coating liquid which contains a binder and composite particles composed of a conjugated conductive polymer and polymer seed particles formed into protective colloids by a polyanion; coating a substrate with the coating liquid and drying the coating liquid to form a coating layer; and heat-stretching the coating layer to form a conductive film. The glass transition temperature of the polymer seed particles formed into protective colloids is lower than a stretching temperature in the heat stretching.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a conductive film formed by stretching.

Resin films are used in a wide range of applications because they are excellent in processability and can impart a wide variety of properties. On the other hand, a resin film is generally insulative and easily charged with static electricity, and thus has a disadvantage that it easily causes impurities and dust to adhere to it and ignites combustibles due to discharge. In particular, in the electric / electronic field, when a resin film is used for an electronic component, the electronic component may be damaged.
For this reason, in particular, in a resin film used in applications such as the electric / electronic field, it is required to impart antistatic performance. For example, conventionally, an antistatic film made of a resin film coated with a conductive film has been used for bags for packaging electronic parts, surface protective films, temporary adhesive tapes, and the like.

  Moreover, in a touch panel, an organic electroluminescence element, a thin film solar cell, and the like, a transparent electrode in which a transparent conductive film is formed on a transparent resin film is used.

Conventionally, the conductive material used for the conductive film as described above has been a surfactant, carbon, metal, metal oxide, or the like. However, in recent years, conductive polymers have attracted attention as an alternative to these. Has been.
For example, Patent Document 1 discloses that an antistatic layer is formed by applying a coating liquid containing a conductive polymer (conductive polymer resin) and a polyurethane resin as a binder on a uniaxially stretched polyester film. There has been proposed a method for producing a biaxially stretched antistatic polyester film by re-stretching the polyester film on which is formed.
Patent Document 2 describes a transparent conductive film including a base material and a conductive layer containing conductive polymer (conductive polymer) particles having a large aspect ratio and a binder resin.

  In addition, as a method for producing a conductive polymer dispersion used in a coating liquid for forming a conductive film, for example, Patent Document 3 discloses that a monomer for obtaining a conjugated conductive polymer is protected with a polyanion. There has been proposed a method of obtaining a conductive polymer dispersion by polymerizing in a dispersion medium containing colloidal seed particles.

  By the way, in the processing of a resin film, stretching treatment is generally performed for the purpose of thinning, improving heat resistance and cold resistance, imparting heat shrinkability (shrinkability), imparting polarization characteristics, and improving mechanical strength. Has been done. According to the so-called in-line coating in which the coating process for forming the conductive film and such a stretching process are continuously performed, the stretching process of the resin film that has not been coated yet and the coating process are provided separately. Compared with the so-called off-line coating, the manufacturing facility can be reduced and the manufacturing cost can be reduced, and the thickness of the conductive film can be adjusted by the stretch ratio.

JP 2010-37533 A JP 2014-26875 A International Publication No. 2014/142133

  Although the conductive polymer dispersion described in Patent Document 3 contains seed particles, thickening of the dispersion is suppressed, and the dispersion is obtained with excellent productivity. When the coating layer formed using the coating liquid is stretched to form a conductive film, there is a problem that the rate of decrease in conductivity with respect to the degree of stretching is large.

  The present invention has been made to solve the above technical problem, and when forming a conductive film by stretching a coating layer formed using a coating liquid containing a conductive polymer, the conductive film It aims at providing the manufacturing method of the electrically conductive film which can suppress the fall of the electrical conductivity of this.

  The present invention pays attention to the form of particles containing a conductive polymer in a coating liquid for forming a conductive film, and the particles are deformed as the coating layer is stretched by the coating liquid. This is based on the knowledge that the decrease in conductivity is suppressed.

That is, the present invention provides the following [1] to [15].
[1] A step of preparing a coating liquid containing composite particles of polymer seed particles protected with a polyanion and a conjugated conductive polymer, and a binder, and a binder; and coating a polymer film substrate with the coating liquid; A step of drying to form a coating layer; and a step of heating and stretching the coating layer to form a conductive film, wherein the glass transition temperature of the protective colloidal polymer seed particles is a stretching temperature in the heating and stretching. The manufacturing method of the electrically conductive film characterized by the above-mentioned.
[2] The method for producing a conductive film according to [1], wherein the glass transition temperature is lower by 10 ° C. or more than the stretching temperature.
[3] The method for producing a conductive film according to the above [1] or [2], wherein the polymer seed particles are made of a polymer containing one or more ethylenically unsaturated monomers as constituent units.
[4] The method for producing a conductive film according to any one of [1] to [3], wherein the content of the composite particles in the solid content of the coating liquid is 1 to 70% by mass.
[5] The method for producing a conductive film according to any one of [1] to [4], wherein in the step of preparing the coating liquid, the composite particles are provided as a dispersion.
[6] The method for producing a conductive film according to any one of [1] to [5], wherein the binder is a thermoplastic resin.
[7] The binder is selected from polyester resin, acrylic resin, polyurethane resin, polyvinyl alcohol resin, polyamide resin, polyimide resin, vinyl ester resin, polystyrene resin, polyvinyl chloride resin, polyolefin resin, polycarbonate resin, and cellulose resin. The manufacturing method of the electrically conductive film of any one of said [1]-[6] which is 1 or more types.
[8] The monomer that is a constituent unit of the conjugated conductive copolymer may have a pyrrole which may have a substituent, an aniline which may have a substituent, and a substituent. The manufacturing method of the electrically conductive film of any one of said [1]-[7] containing 1 or more types chosen from thiophene.
[9] The monomer according to any one of [1] to [8], wherein the monomer that is a constituent unit of the conjugated conductive copolymer includes a compound represented by the following formula (1). Manufacturing method of electrically conductive film.

(In Formula (1), R ¹ and R ² are each independently a hydrogen atom, a hydroxyl group, an optionally substituted alkyl group having 1 to 18 carbon atoms, or an optionally substituted carbon number. Any one of 1 to 18 alkoxy groups, an optionally substituted alkylthio group having 1 to 18 carbon atoms, or a substituent in which R ¹ and R ² are bonded to each other to form a ring; An alicyclic ring having 3 to 10 carbon atoms, an aromatic ring having 6 to 10 carbon atoms that may have a substituent, and an oxygen atom-containing complex having 3 to 10 ring members that may have a substituent A ring, a sulfur atom-containing heterocycle having 3 to 10 ring members that may have a substituent, or a sulfur atom and oxygen atom-containing heterocycle having 3 to 10 ring members that may have a substituent.
[10] The method for producing a conductive film according to any one of the above [1] to [9], wherein the polyanion is a polymer having a group comprising a sulfonic acid or a salt thereof.
[11] The above [1] to [11], wherein the content of the anionic group in the polyanion is 0.25 to 30 mol with respect to 1 mol of the monomer which is a constituent unit of the conjugated conductive copolymer. [10] The method for producing a conductive film according to any one of [10].

[12] The method for producing a conductive film according to any one of [1] to [11], wherein the conductive film is a transparent conductive film.
[13] Production of the conductive film according to any one of [1] to [12], wherein in the heat stretching, the coating layer is peeled from the polymer film substrate, and then only the coating layer is stretched. Method.
[14] The method for producing a conductive film according to any one of [1] to [12], wherein the coating layer on the polymer film substrate is stretched together with the polymer film substrate in the heat stretching.
[15] A method for producing an antistatic film, wherein the antistatic film comprising the conductive film and the polymer film substrate is obtained by the production method according to [14]. A method for producing a film.

According to the present invention, when a conductive film is formed by stretching a coating layer formed using a coating liquid containing a conductive polymer, the conductive film can suppress a decrease in the conductivity of the conductive film. A manufacturing method is provided.
Therefore, the manufacturing method of the electrically conductive film of this invention can be used suitably for manufacture of a transparent conductive film, an antistatic film, etc.

4 is a graph showing the relationship between the stretching ratio and conductivity of conductive films in Examples 1 and 2 and Comparative Example 1. It is the graph which showed the relationship between the extending | stretching rate of the electrically conductive film in Example 3 and the comparative example 2, and electrical conductivity. It is the graph which showed the relationship between the extending | stretching rate of the electrically conductive film in Example 4 and the comparative example 3, and electrical conductivity.

Hereinafter, the present invention will be described in detail.
The method for producing a conductive film of the present invention comprises a step of preparing a coating solution containing composite seeds of polymer seed particles protected with a polyanion and a conjugated conductive polymer, and a binder, and a polymer containing the coating solution. The method includes a step of coating a film substrate and drying to form a coating layer, and a step of heating and stretching the coating layer to form a conductive film.
That is, the manufacturing method of the electrically conductive film of this invention passes through a coating liquid preparation process, the coating layer formation process using the said coating liquid, and the electrically conductive film formation process by the heating extending | stretching of the said coating layer.
The “polyanion” referred to in the present invention means a polymer having two or more anionic groups. Further, “protective colloidalization” means that the surface of the polymer seed particle is protected with a polyanion.

And in this invention, the glass transition temperature of the said polymer colloid-ized polymer seed particle is characterized by being lower than the extending | stretching temperature in the said heating extending | stretching.
As described above, since the glass transition temperature of the protective colloidal polymer seed particles is lower than the stretching temperature, it is possible to suppress a decrease in the conductivity of the conductive film due to stretching. This is because by heating and stretching at a stretching temperature that is higher than the glass transition temperature, the polymer seed particles are also deformed following the stretching, and the expansion of the distance between the composite particles due to stretching is suppressed. Presumed to be.

[Coating solution preparation process]
In this step, as a coating liquid for forming a coating layer, a coating liquid containing polymer seed particles protected with a polyanion and colloidal particles of polymer seed particles and a conjugated conductive polymer, and a binder is prepared.
Specifically, a coating liquid is obtained by mixing composite particles, a binder, and other components added as necessary in a dispersion medium.

(Composite particles)
The composite particle here is a composite particle of a polymer seed particle protected with a polyanion and made into a protective colloid and a conjugated conductive polymer. More specifically, the polyanion is coordinated to the surface of the polymer seed particle to form a protective colloid, and the polyanion is a particle doped with a conjugated conductive polymer.

The content of the conjugated conductive polymer in the composite particles is 2.7 to 77% by mass from the viewpoint of the conductivity of the coating layer formed using the coating liquid containing the conjugated conductive polymer. It is preferable that it is preferably 3.2 to 50% by mass, and more preferably 3.9 to 44% by mass.
The content of the polymer seed particles in the polymer seed particles protected with a polyanion is 10 to 100 with respect to 100 parts by mass of the polyanion from the viewpoint of the stability of the polymer seed particles protected with a polyanion. It is preferable that it is a mass part, More preferably, it is 20-90 mass parts, More preferably, it is 30-60 mass parts.

  The composite particle content in the solid content of the coating liquid is a value that assumes that the total amount of the conjugated conductive polymer is combined with the polymer seed particles, and can be calculated from the raw material charge amount at the time of preparing the coating liquid. . The composite particle content is preferably 1 to 70% by mass, more preferably 5 to 70% by mass, and still more preferably 30 to 70% from the viewpoint of the conductivity of the conductive film and the strength against stretching of the coating layer. % By mass.

(Polymer seed particles)
Polymer seed particles are particles that are protective colloidalized by polyanions in a dispersion medium. As the polymer seed particles, for example, those composed of a polymer containing one or more ethylenically unsaturated monomers as constituent units are preferable. The polymer may be a single type or a mixture of two or more types, and may be crystalline or amorphous. In the case of crystallinity, the crystallinity is preferably 50% or less.
Any ethylenically unsaturated monomer may be used as long as it has at least one polymerizable ethylenic carbon-carbon double bond. For example, (meth) acrylate having a linear, branched or cyclic alkyl group; aromatic vinyl compound such as styrene and α-methylstyrene; heterocyclic vinyl compound such as vinylpyrrolidone; hydroxyalkyl (meth) acrylate; Dialkylaminoalkyl (meth) acrylates such as 2-ethylhexyl (meth) acrylate; Vinyl esters such as vinyl acetate and vinyl alkanoate; Monoolefins such as ethylene, propylene, butylene and isobutylene; Conjugated diolefins such as butadiene, isoprene and chloroprene ; Α, β-unsaturated mono- or dicarboxylic acids such as (meth) acrylic acid, crotonic acid, itaconic acid, maleic acid and fumaric acid; vinyl cyanide compounds such as acrylonitrile; carbonyl groups such as acrolein and diacetone acrylamide Vinyl compounds, and the like. These may be used alone or in combination of two or more.
In the present specification, “(meth) acryl” refers to acryl or methacryl, and “(meth) acrylate” refers to acrylate or methacrylate.
Of these, the ethylenically unsaturated monomer preferably contains an aromatic vinyl compound, and more preferably contains styrene. In this case, it is preferable that 10 mass% or more of aromatic vinyl compounds are contained among ethylenically unsaturated monomers, More preferably, it is 20-100 mass%, More preferably, it is 30-100 mass%.

Moreover, the ethylenically unsaturated monomer may contain a crosslinkable monomer, and may be crosslinked in combination with each other or with an ethylenically unsaturated compound having an active hydrogen group. By using a crosslinked copolymer, the water resistance, moisture resistance, heat resistance, etc. of the conductive film can be improved. The crosslinkable monomer is a compound having two or more ethylenic carbon-carbon double bonds, or one or more ethylenic carbon-carbon double bonds and one other reactive group. The compound which has the above is said.
Examples of the crosslinkable monomer include epoxy group-containing α, β-ethylenically unsaturated compounds such as glycidyl (meth) acrylate; hydrolyzable alkoxysilyl such as vinyltriethoxysilane and γ-methacryloxypropyltrimethoxysilane. Group-containing α, β-ethylenically unsaturated compounds; polyfunctional vinyl compounds such as ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, allyl (meth) acrylate, divinylbenzene, diallyl phthalate .
In addition, by using a crosslinkable monomer such as a carbonyl group-containing α, β-ethylenically unsaturated compound (a ketone group-containing compound), a polyhydrazine compound (particularly oxalic acid dihydrazide, succinic acid dihydrazide, adipic acid dihydrazide, It may be crosslinked in combination with those having two or more hydrazide groups such as polyacrylic acid hydrazide.
The content of the crosslinkable monomer in the ethylenically unsaturated monomer is preferably 50% by mass or less, more preferably 35% by mass or less, and further preferably 25% by mass or less.

<Glass transition temperature>
In the present invention, the polymer seed particles protected with a polyanion as a protective colloid have a glass transition temperature lower than the stretching temperature at the time of heat stretching in the subsequent conductive film forming step, preferably 10 ° C. or more, more preferably It shall be 15 ° C or more lower. It can suppress that the electrical conductivity of the electrically conductive film formed by extending | stretching falls because the said glass transition temperature is lower than the extending | stretching temperature in the heating extending | stretching of the coating layer formed using the coating liquid.
From the viewpoint of preventing blocking of the conductive film, the glass transition temperature is preferably −20 ° C. or higher, more preferably −10 ° C. or higher, and further preferably 0 ° C. or higher.
In addition, the upper limit of the absolute value of the temperature difference with respect to the extending | stretching temperature in the heating extending | stretching of the said glass transition temperature will not be specifically limited if resin which comprises a polymer seed particle does not produce deterioration by heating extending | stretching.

  The glass transition temperature referred to in the present invention is determined by differential scanning calorimetry (DSC: Differential scanning calorimetry (DSC) based on JIS K 7121: 2012 for a sample obtained by drying polymer seed particles protected with a polyanion in a nitrogen gas atmosphere. scanning calorimetry) to obtain an intermediate glass transition temperature obtained from the obtained DSC curve. Specifically, it is measured by the method described in the following examples.

The glass transition temperature can be estimated from the composition of the ethylenically unsaturated monomer, which is a constituent unit of the copolymer constituting the polymer seed particle, using the following FOX equation.
1 / Tg = W ₁ / Tg ₁ + W ₂ / Tg ₂ +... + W _n / Tg _n
(Here, Tg is a glass transition temperature [unit: K] of a polymer having each ethylenically unsaturated monomer as a structural unit, and W ₁ , W ₂ ,..., W _n are each ethylene. is the weight fraction of the sex unsaturated _{monomer, Tg 1, Tg 2, ···} , Tg n is the glass transition temperature of the homopolymer of each ethylenic unsaturated monomer [unit: K] is .)
As the glass transition temperature of the homopolymer of the ethylenically unsaturated monomer used in the above calculation, the values described in known literatures can be used.

  In controlling the glass transition temperature, the combination of ethylenically unsaturated monomers is not particularly limited. For example, using two types of monomers, a high glass transition temperature monomer and a low glass transition temperature monomer, the glass transition temperature is estimated and controlled by changing the composition ratio in light of the FOX equation. can do. Examples of the monomer having a high glass transition temperature include styrene, methyl methacrylate, cyclohexyl methacrylate, and isobornyl methacrylate. Examples of the monomer having a low glass transition temperature include methyl acrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate.

(Polyanion)
The polyanion is a polymer having two or more anionic groups, coordinates to the surface of the polymer seed particle to form a protective colloid, and functions as a dopant to the conjugated conductive polymer.
Examples of the anionic group include a group consisting of sulfonic acid or a salt thereof, a group consisting of phosphoric acid or a salt thereof, a monosubstituted phosphate group, a group consisting of a carboxylic acid or a salt thereof, a monosubstituted sulfate group, and the like. It is done. Among these, a strongly acidic group is preferable, a group consisting of sulfonic acid or a salt thereof, and a group consisting of phosphoric acid or a salt thereof are more preferable, and a group consisting of sulfonic acid or a salt thereof is more preferable.
The anionic group may be directly bonded to the main chain of the polymer or may be bonded to the side chain. When the anionic group is bonded to the side chain, the doping effect becomes more prominent, so it is preferable that the anionic group is bonded to the end of the side chain.

  The polyanion may have a substituent other than the anionic group. Examples of the substituent include alkyl group, hydroxy group, alkoxy group, phenol group, cyano group, phenyl group, hydroxyphenyl group, ester group, halogeno group, alkenyl group, imide group, amide group, amino group, oxycarbonyl Group, carbonyl group and the like. Among these, an alkyl group, a hydroxy group, a cyano group, a hydroxyphenyl group, and an oxycarbonyl group are preferable, and an alkyl group, a hydroxy group, and a cyano group are more preferable. These substituents may be directly bonded to the main chain of the polyanion or may be bonded to the side chain. When the said substituent is couple | bonded with the side chain, it is preferable to have couple | bonded with the terminal of the side chain from a viewpoint of the effective effect | action of this substituent.

The alkyl group among the substituents has an effect of improving solubility or dispersibility in a dispersion medium, compatibility with a conjugated conductive polymer, dispersibility, and the like. Specific examples of the alkyl group include a chain alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, a t-butyl group, a pentyl group, a hexyl group, an octyl group, a decyl group, and a dodecyl group; Examples thereof include cycloalkyl groups such as propyl group, cyclopentyl group, and cyclohexyl group. In view of solubility in a dispersion medium, dispersibility in a conjugated conductive polymer, steric hindrance, and the like, an alkyl group having 1 to 12 carbon atoms is more preferable.
The hydroxy group facilitates formation of hydrogen bonds with other hydrogen atoms and the like, and has an effect of improving solubility in a dispersion medium, compatibility with a conjugated conductive polymer, dispersibility, adhesion, and the like. The hydroxy group is preferably bonded to the terminal of the alkyl group having 1 to 6 carbon atoms bonded to the main chain of the polyanion.
A cyano group and a hydroxyphenyl group have an effect of improving compatibility with a conjugated conductive polymer, solubility in a dispersion medium, heat resistance, and the like. The cyano group is preferably bonded directly to the main chain of the polyanion and to at least one of the ends of the alkyl group having 1 to 7 carbon atoms or the alkenyl group having 2 to 7 carbon atoms bonded to the main chain.
The oxycarbonyl group is preferably at least one of an alkyloxycarbonyl group and an aryloxycarbonyl group, and is preferably bonded directly or via another functional group to the main chain of the polyanion.

The composition of the main chain of the polyanion is not particularly limited. Examples of the main chain of the polyanion include polyalkylene, polyimide, polyamide, and polyester. Among these, polyalkylene is preferable from the viewpoint of synthesis and availability.
The polyalkylene is a polymer having an ethylenically unsaturated monomer as a structural unit, and may have a carbon-carbon double bond in the main chain. Specific examples of polyalkylene include polyethylene, polypropylene, polybutene, polypentene, polyhexene, polyvinyl alcohol, polyvinylphenol, poly (3,3,3-trifluoropropylene), polyacrylonitrile, polyacrylate, polymethacrylate, polystyrene, polybutadiene, Examples include polyisoprene.
Specific examples of polyimides include pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, 2,2,3,3-tetracarboxydiphenyl ether dianhydride, 2,2- [ Obtained by a polycondensation reaction between an acid anhydride such as 4,4′-di (dicarboxyphenyloxy) phenyl] propane dianhydride and a diamine such as oxydianiline, paraphenylenediamine, metaphenylenediamine, or benzophenonediamine. A polymer is mentioned.
Specific examples of the polyamide include nylon 6, nylon 66, nylon 610, and the like.
Specific examples of the polyester include polyethylene terephthalate and polybutylene terephthalate.

  Among the polyanions, in particular, from the viewpoints of the stability of the conjugated conductive polymer and the action of alleviating thermal decomposition, a polymer having a main chain of polyalkylene and further having a group consisting of sulfonic acid or a salt thereof is provided. preferable. Specific examples include polyvinylsulfonic acid, polystyrenesulfonic acid, polyallylsulfonic acid, polyacrylic acid ethylsulfonic acid, polyacrylic acid butylsulfonic acid, poly (2-acrylamido-2-methylpropanesulfonic acid), polyisoprenesulfonic acid. And alkali metal salts thereof. These polymers may be a single polymer or two or more types of copolymers. Among these, from the viewpoint of imparting electrical conductivity, polystyrene sulfonic acid, polyisoprene sulfonic acid, polyacrylic acid ethyl sulfonic acid, polyacrylic acid butyl sulfonic acid, and sodium or potassium salts thereof are preferable, and polystyrene sulfonic acid and More preferred is sodium polystyrene sulfonate.

  The polyanion preferably has a weight average molecular weight of 1,000 to 1,000,000, more preferably 10,000 to 500,000, still more preferably 50,000 to 300,000. When the weight average molecular weight is within the above range, the solubility of the polyanion in the dispersion medium and the compatibility with the conjugated conductive polymer are good. In addition, the weight average molecular weight said here is the value measured as polystyrene sulfonic acid conversion molecular weight using the gel permeation chromatography.

  As the polyanion, a commercially available product can be used, or it can be synthesized by a known method. As a method for synthesizing a polyanion, for example, the method described in JP-A-2005-76016, Houben-Weyl, “Methoden der organischen Chemie”, Vol. E20, Makromolekulare Stoffe, No. 2, 1987, p. Is mentioned.

  From the viewpoint of obtaining composite particles having sufficient conductivity and dispersibility, the content of the anionic group in the polyanion is 0.25 to 1 mol of the monomer that is a constituent unit of the conjugated conductive polymer. It is preferable that it is 30 mol, More preferably, it is 0.8-25 mol, More preferably, it is 1-20 mol.

(Conjugated conductive polymer)
The conjugated conductive polymer referred to in the present invention is an organic polymer compound having a π-conjugated system in the main chain, and is not particularly limited as long as it is such a polymer compound. Examples of the conjugated conductive polymer include polypyrroles, polythiophenes, polyacetylenes, polyphenylenes, polyphenylene vinylenes, polyanilines, polyacenes, polythiophene vinylenes, and copolymers thereof. Among these, polypyrroles, polyanilines and polythiophenes are preferable, and polythiophenes are more preferable. The conjugated conductive polymer preferably has a substituent such as an alkyl group, a carboxy group, a sulfonic acid group, an alkoxy group, a hydroxyl group, and a cyano group from the viewpoint of obtaining high conductivity. The “class” in the compound notation referred to in the present specification means a compound group including the compound structure. For example, the polypyrrole refers to a compound group including a polypyrrole structure.

Specific examples of preferred conjugated conductive polymers include polypyrrole, poly (N-methylpyrrole), poly (3-methylpyrrole), poly (3-ethylpyrrole), poly (3-n-propylpyrrole), poly (3-butylpyrrole), poly (3-octylpyrrole), poly (3-decylpyrrole), poly (3-dodecylpyrrole), poly (3,4-dimethylpyrrole), poly (3,4-dibutylpyrrole) , Poly (3-carboxypyrrole), poly (3-methyl-4-carboxypyrrole), poly (3-methyl-4-carboxyethylpyrrole), poly (3-methyl-4-carboxybutylpyrrole), poly (3 -Hydroxypyrrole), poly (3-methoxypyrrole), poly (3-ethoxypyrrole), poly (3-butoxypyrrole), poly (3 Polypyrroles such as hexyloxypyrrole), poly (3-methyl-4-hexyloxypyrrole), poly (3-methyl-4-hexyloxypyrrole); polythiophene, poly (3-methylthiophene), poly (3-ethyl) Thiophene), 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-dibutylthiophene), poly (3-hydroxythiophene), poly (3-methoxythiophene), poly (3-ethoxythiophene), poly (3-butoxythiophene), poly (3-hexyloxythiophene), poly (3-heptyloxythiophene), poly (3-octyloxythiophene), poly (3-decyloxythiophene), poly (3-dodecyloxythiophene), poly (3-octadecyloxythiophene), poly (3,4 Dihydroxythiophene), poly (3,4-dimethoxythiophene), poly (3,4-diethoxythiophene), poly (3,4-dipropoxythiophene), poly (3,4-dibutoxythiophene), poly (3 , 4-Dihexyloxythiophene), poly (3,4-diheptyloxythiophene) ), Poly (3,4-dioctyloxythiophene), poly (3,4-didecyloxythiophene), poly (3,4-didodecyloxythiophene), poly (3,4-ethylenedioxythiophene), Poly (3,4-propylenedioxythiophene), poly (3,4-butylenedioxythiophene), poly (3-methyl-4-methoxythiophene), poly (3-methyl-4-ethoxythiophene), poly ( 3-carboxythiophene), poly (3-methyl-4-carboxythiophene), poly (3-methyl-4-carboxyethylthiophene), poly (3-methyl-4-carboxybutylthiophene), poly (3,4- Polythiophenes such as ethyleneoxythiathiophene); polyaniline, poly (2-methylaniline), poly (3-isobutene) Ruanirin), poly (2-aniline sulfonic acid) and poly (3-aniline sulfonic acid) polyanilines such like. These may be used alone or as a mixture of two or more.
Among these, from the viewpoint of high conductivity, polypyrrole, polythiophene, poly (N-methylpyrrole), poly (3-methylthiophene), poly (3-methoxythiophene) and poly (3,4-ethylenedioxythiophene) Is preferred. In particular, poly (3,4-ethylenedioxythiophene) is preferable because of high conductivity and excellent heat resistance.

The monomer which is a constituent unit of the conjugated conductive polymer is selected from among pyrrole which may have a substituent, aniline which may have a substituent, and thiophene which may have a substituent. It is preferable that it contains one or more selected. In the present specification, “may have a substituent” means to include both the case of having a substituent and the case of not having a substituent.
Examples of the substituent include an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 10 carbon atoms, a heteroaryl group having 5 to 10 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, and an alkyl group having 1 to 18 carbon atoms. Examples thereof include an alkylthio group, a carboxy group, a hydroxyl group, a halogen atom, and a cyano group. In addition, these alkyl groups, aryl groups, heteroaryl groups, alkoxy groups, and alkylthio groups may be substituted with one or more selected from a carboxy group, a hydroxyl group, a halogen atom, and a cyano group. Two or more of the substituents may be condensed to form a ring.

  Specific examples of the 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-carboxypyrrole, 3-methyl-4-carboxypyrrole, 3-methyl-4-carboxyethylpyrrole, 3-methyl-4-carboxybutyl Pyrrole such as pyrrole, 3-hydroxypyrrole, 3-methoxypyrrole, 3-ethoxypyrrole, 3-butoxypyrrole, 3-hexyloxypyrrole, 3-methyl-4-hexyloxypyrrole, 3-methyl-4-hexyloxypyrrole Thiophene, 3-methylthiophene, 3-ethylthiophene , 3-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 Phen, 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-butylene Oxythiophene, 3-methyl-4-methoxythiophene, 3-methyl-4-ethoxythiophene, 3-carboxythiophene, 3-methyl-4-carboxythiophene, 3-methyl-4-carboxyethylthiophene, 3-methyl-4 -Carboxybutylthiophene, 3,4-ethyleneoxythio Examples include thiophenes such as athiophene; anilines such as aniline, 2-methylaniline, 3-isobutylaniline, 2-anilinesulfonic acid, and 3-anilinesulfonic acid. These may be used alone or in combination of two or more as long as the conjugated conductive polymer can be obtained by polymerization.

  Among these, it is preferable that the monomer includes a compound represented by the following formula (1).

In formula (1), R ¹ and R ² each independently represent a hydrogen atom, a hydroxyl group, an optionally substituted alkyl group having 1 to 18 carbon atoms, or an optionally substituted carbon number 1 Or an alkoxy group having 1 to 18 carbon atoms which may have a substituent, or a substituent in which R ¹ and R ² are bonded to each other to form a ring. An alicyclic ring having 3 to 10 carbon atoms, an aromatic ring having 6 to 10 carbon atoms that may have a substituent, and an oxygen-containing heterocyclic ring having 3 to 10 ring members that may have a substituent And a sulfur atom-containing heterocyclic ring having 3 to 10 ring members that may have a substituent, or a sulfur atom and oxygen atom-containing heterocyclic ring having 3 to 10 ring members that may have a substituent. In addition, carbon number of a substituent shall not be included in each said carbon number.

Specific examples of the oxygen atom-containing heterocycle include oxirane ring, oxetane ring, furan ring, hydrofuran ring, pyran ring, pyrone ring, dioxane ring, and trioxane ring.
Specific examples of the sulfur atom-containing heterocyclic ring include thiirane ring, thietane ring, thiophene ring, thiane ring, thiopyran ring, thiopyrylium ring, benzothiopyran ring, dithiane ring, dithiolane ring, and trithiane ring.
Specific examples of the sulfur atom and oxygen atom-containing heterocycle include an oxathiolane ring and an oxathian ring.

Examples of the substituent in R ¹ and R ² in the formula (1) include an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 10 carbon atoms, a heteroaryl group having 5 to 10 carbon atoms, and 1 carbon atom. -18 alkoxy groups, C1-C18 alkylthio groups, carboxy groups, hydroxyl groups, halogen atoms, cyano groups and the like. In addition, these alkyl groups, aryl groups, heteroaryl groups, alkoxy groups, and alkylthio groups may be substituted with one or more of a carboxy group, a hydroxyl group, a halogen atom, and a cyano group. Two or more of the substituents may be condensed to form a ring.

  The compound represented by the formula (1) is more preferably a compound represented by the following formula (2).

In Formula (2), R ³ and R ⁴ are each independently any one of a hydrogen atom, a hydroxyl group, and an optionally substituted alkyl group having 1 to 4 carbon atoms, or R ³ and R 4. ⁴ represents an oxygen atom-containing heterocycle having 5 or 6 ring members, which may have a substituent, which is bonded to each other to form a ring.
In addition, carbon number of a substituent shall not be included in each said carbon number.
R ³ and R ⁴ are preferably an oxygen atom-containing heterocyclic ring having 5 or 6 ring members, which may have a substituent, in which R ³ and R ⁴ are bonded to each other to form a ring. Examples of such an oxygen atom-containing heterocyclic ring include a dioxane ring and a trioxane ring, and a dioxane ring is more preferable.
Of the compounds represented by the formula (2), 3,4-ethylenedioxythiophene is particularly preferable.

Examples of the substituent in R ³ and R ⁴ of the formula (2) include an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 10 carbon atoms, a heteroaryl group having 5 to 10 carbon atoms, and 1 carbon atom. -18 alkoxy groups, C1-C18 alkylthio groups, carboxy groups, hydroxyl groups, halogen atoms, cyano groups and the like. In addition, these alkyl groups, aryl groups, heteroaryl groups, alkoxy groups, and alkylthio groups may be substituted with one or more of a carboxy group, a hydroxyl group, a halogen atom, and a cyano group. Two or more of the substituents may be condensed to form a ring.

(Composite particle dispersion)
The composite particles are preferably provided in a dispersion state from the viewpoint of improving stability and dispersibility. In addition to the method in which the dispersion of the composite particles is mixed with the seed particles protected with a polyanion and a conjugated conductive polymer in a dispersion medium, for example, the conductive weight described in Patent Document 3 is used. It can be obtained by a method for producing a coalescence-containing dispersion. Specifically, the dispersion containing the composite particles is obtained by a method in which a monomer that is a constituent unit of a conjugated conductive polymer is polymerized in a dispersion medium containing seed particles protected with a polyanion. Can do. In this case, the liquid used for the dispersion containing the composite particles can be used as part or all of the liquid for preparing the coating liquid. In addition, the composite particle dispersion may contain some of a composite composed of a polyanion and a conjugated conductive polymer, that is, a conductive polymer that does not include polymer seed particles.

(binder)
The binder is used for the purpose of fixing the composite particles on the polymer film substrate to form a conductive coating layer. A film forming property that can be dissolved or dispersed in a dispersion medium used for the coating liquid is used. Moreover, when extending | stretching a coating layer with a polymer film base material at the time of heat-stretching, what can be extended | stretched following extension of this base material is used.
As the binder, a thermoplastic resin is preferable. Even a thermosetting resin or an ultraviolet curable resin can be applied as long as it can be stretched by heating. In this case, it can be cured after stretching.

The content of the binder in the solid content of the coating liquid is preferably 30 to 70% by mass, more preferably 32 from the viewpoints of film forming property, adhesion to the polymer film substrate, conductivity of the conductive film, and the like. It is -68 mass%, More preferably, it is 35-65 mass%.
Moreover, it is preferable that a binder is melt | dissolved or disperse | distributed to the aqueous medium of a coating liquid from a viewpoint of application to in-line coating. In this case, a hydrophilic group such as a sulfonic acid group or a carboxy group may be introduced into the resin used for the binder, or the dispersibility may be improved by using a surfactant. In addition, solid content is a non-volatile content measured as solid content concentration in the Example mentioned later. Specifically, polyanions, polymer seed particles, conjugated conductive copolymers, and other nonvolatile components are included.

Specific examples of the binder include polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; acrylic resins; polyurethane resins; polyvinyl alcohol resins; polyamides such as polyamide 6, polyamide 6, 6, polyamide 12, and polyamide 11. Resin; Polyimide resin; Vinyl ester resin; Polystyrene resin; Polyvinyl chloride resin; Polyolefin resin; Polycarbonate resin; Cellulosic resin; Polyether imide resin; Polyvinylidene fluoride, Polyvinyl fluoride, Polytetrafluoroethylene, Ethylenetetrafluoro Fluorine resins such as ethylene copolymer and polychlorotrifluoroethylene; vinyl such as polyvinyl ether, polyvinyl butyral, and polyvinyl acetate Fats; epoxy resins; urea resins; melamine resins; phenolic resins; oxetane resin; xylene resins; aramid resins; polyimide silicone resin and the like, can also be used polysaccharides such as starch. These may be used alone or in combination of two or more. It can be appropriately selected and used according to the adhesion with the polymer film substrate, the application and performance of the conductive film, and the like. Among these, polyester resin, acrylic resin, polyurethane resin, polyvinyl alcohol resin, polyamide resin, polyimide resin, vinyl ester resin, polystyrene resin, polyvinyl chloride resin, polyolefin resin, polycarbonate resin, and cellulose resin are more preferable, Polyester resin, acrylic resin, polyurethane resin and polyvinyl alcohol resin are used.
Hereinafter, among these, representative resins will be described in more detail.

<Polyester resin>
The polyester resin is a linear polyester having a dicarboxylic acid component and a polyol component as monomer constituent units. This polyester resin can be synthesized by a conventional polycondensation reaction.
The glass transition temperature of the polyester resin is preferably 20 ° C. or higher, more preferably 30 ° C. or higher, and further preferably 40 ° C. from the viewpoints of adhesion to the polymer film substrate and blocking inhibition in the coating layer. That's it.

  Dicarboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, adipic acid, sebacic acid, phenylindanedicarboxylic acid, A dimer acid etc. are mentioned. These may be used alone or in combination of two or more. The dicarboxylic acid component is an unsaturated polybasic acid such as maleic acid, fumaric acid or itaconic acid, or a hydroxycarboxylic acid such as p-hydroxybenzoic acid or p- (β-hydroxyethoxy) benzoic acid. 10 mol% or less, preferably 7 mol% or less, more preferably 5 mol% or less may be used in combination.

  As the polyol component, ethylene glycol, 1,4-butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, xylylene glycol, dimethylolpropionic acid, glycerin , Trimethylolpropane, poly (ethyleneoxy) glycol, poly (tetramethyleneoxy) glycol, alkylene oxide adduct of bisphenol A, alkylene oxide adduct of hydrogenated bisphenol A, and the like. These may be used alone or in combination of two or more. Among these, ethylene glycol, ethylene oxide or propylene oxide adduct of bisphenol A, and 1,4-butanediol are more preferable, and ethylene glycol or ethylene oxide or propylene oxide adduct of bisphenol A is more preferable.

When the polyester resin is dissolved or dispersed in the aqueous medium of the coating liquid, the polyester resin is a group having a group consisting of a sulfonate or a group consisting of a carboxylic acid or a salt thereof in order to improve solubility or dispersibility. One or two or more types selected from the compounds having the above may be copolymerized. The content of monomers having these compounds as structural units in the polyester resin is preferably 50 mol% or less based on the total of the dicarboxylic acid component and the polyol component, which are monomer structural units of the polyester resin. More preferably, it is 40 mol% or less, More preferably, it is 30 mol% or less.
Specific examples of the compound having a group consisting of a sulfonate include 5-sodium sulfoisophthalic acid, 5-ammonium sulfoisophthalic acid, 4-sodium sulfoisophthalic acid, 4-methylammonium sulfoisophthalic acid, and 2-sodium sulfoisophthalic acid. Sulphonic acid alkali metal salts or sulphonic acid amine salt compounds such as 5-potassium sulfoisophthalic acid, 4-potassium sulfoisophthalic acid, 2-potassium sulfoisophthalic acid and sodium sulfosuccinic acid.
Specific examples of the compound having a group consisting of a carboxylic acid or a salt thereof include trimellitic anhydride, trimellitic acid, pyromellitic anhydride, pyromellitic acid, trimesic acid, cyclobutanetetracarboxylic acid, dimethylolpropionic acid, or these And monoalkali metal salts. In addition, a free carboxy group is made into the group which consists of carboxylate by making an alkali metal compound and an amine compound act after copolymerization.

<Acrylic resin>
The acrylic resin is a polymer having as a constituent unit an ethylenically unsaturated monomer of a type represented by a (meth) acrylic monomer. Either a homopolymer or a copolymer may be used. Further, it may be a block copolymer or graft copolymer with another copolymer such as polyester or polyurethane. Furthermore, the acrylic resin referred to herein includes a polymer obtained by polymerizing the ethylenically unsaturated monomer in a solution or dispersion containing another copolymer such as polyester or polyurethane, or a polymer thereof. A mixture of
The glass transition temperature of the acrylic resin is preferably 20 ° C. or higher, more preferably 30 ° C. or higher, more preferably 40 ° C. or higher, from the viewpoints of adhesion to the polymer film substrate and blocking inhibition in the coating layer. It is.

  The ethylenically unsaturated monomer that is a (meth) acrylic monomer is not particularly limited, but specific examples include (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid. , Carboxy group-containing monomers such as citraconic acid, and salts thereof; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, monobutyl hydroxyl fumarate Hydroxyl group-containing monomers such as monobutyl hydroxyitaconate; (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate; (Meth) acrylamide, diacetone acrylamide, N-methylo Le acrylamide, nitrogen-containing monomers such as (meth) acrylonitrile.

  Examples of the acrylic resin include styrene derivatives such as styrene, α-methylstyrene, divinylbenzene, and vinyl toluene; vinyl ester compounds such as vinyl acetate and vinyl propionate; γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, Silicon-containing compounds such as methacryloyl silicon macromer; phosphorus-containing vinyl compounds; vinyl halides such as vinyl chloride, biliden chloride, vinyl fluoride, vinylidene fluoride, trifluorochloroethylene, tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, etc. Compound: One or two or more polymerizable monomers selected from conjugated diene compounds such as butadiene may be copolymerized. Among the monomer structural units of the acrylic resin, the content of these polymerizable monomers is preferably 50 mol% or less, more preferably 40 mol% or less, and even more preferably 30 mol% or less. .

<Polyurethane resin>
The polyurethane resin is a polymer having a urethane bond in the molecule. A polyurethane resin is generally synthesized by utilizing a reaction between a hydroxyl group and an isocyanato group.

As the compound containing a hydroxyl group, polyol is preferably used, and examples thereof include polyether polyol, polyester polyol, polycarbonate-based polyol, polyolefin polyol, and acrylic polyol. One of these compounds may be used alone, or two or more may be used in combination.
Specific examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polyethylene propylene glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol and the like.
Examples of the polyester polyol include a reaction product of a polyvalent carboxylic acid or an acid anhydride thereof and a polyhydric alcohol. Specific examples of the polyvalent carboxylic acid include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, and isophthalic acid. Specific examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, 1,3-butanediol, 1,4-butanediol, 2,3- Butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-methyl-2,4 -Pentanediol, 2-methyl-2-propyl-1,3-propanediol, 1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexane Diol, 2,5-dimethyl-2,5-hexanediol, 1,9- Nandiol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-butyl-2-hexyl-1,3-propanediol, cyclohexanediol, bishydroxymethylcyclohexane , Dimethanolbenzene, bishydroxyethoxybenzene, alkyl dialkanolamine, lactone diol and the like.
Examples of the polycarbonate-based polyol include polycarbonate diols obtained by dealcoholization reaction from polyhydric alcohol and dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and the like, such as poly (1,6-hexylene) carbonate, poly (3- And methyl-1,5-pentylene) carbonate.

  Examples of the compound containing an isocyanato group include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, and tolidine diisocyanate; α, α, α ′, α′-tetramethylxylylene diene Aliphatic diisocyanates having aromatic rings such as isocyanate; aliphatic diisocyanates such as methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate; cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, isopropyl Polyisocyanate compounds such as alicyclic diisocyanates such as Den dicyclohexyl diisocyanate. These may be used alone or in combination of two or more.

In the synthesis of the polyurethane resin, a known chain extender may be used. As the chain extender for the polyurethane having a terminal isocyanato group, any chain extender having two or more reactive groups with an isocyanato group may be used. Generally, a chain extender having two hydroxyl groups or amino groups is used. .
Examples of chain extenders having two hydroxyl groups include aliphatic glycols such as ethylene glycol, propylene glycol, and butanediol; aromatic glycols such as xylylene glycol and bishydroxyethoxybenzene; esters such as neopentyl glycol hydroxypivalate. And glycols such as glycols.
Examples of the chain extender having two amino groups include aromatic diamines such as tolylenediamine, xylylenediamine, and diphenylmethanediamine; ethylenediamine, propylenediamine, hexanediamine, 2,2-dimethyl-1,3-propanediamine 2-methyl-1,5-pentanediamine, trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine Aliphatic diamines such as 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, isopropylidine -4,4'-diamine, 1,4-diaminocyclohexane, 1,3 -Alicyclic rings such as bisaminomethylcyclohexane Group diamine and the like.

  When the polyurethane resin is dissolved or dispersed in the aqueous medium of the coating liquid, the polyurethane resin is preferably water-soluble or water-dispersible. A water-soluble or water-dispersible polyurethane resin can be obtained by introducing a hydrophilic group such as a hydroxyl group, a carboxy group, a sulfonic acid group, a sulfonyl group, a phosphoric acid group, or an ether group. Among these hydrophilic groups, a carboxy group or a sulfonic acid group is preferable from the viewpoints of adhesion to the polymer film substrate, physical properties of the coating layer, and the like.

<Polyvinyl alcohol resin>
A polyvinyl alcohol resin is a polymer which has a polyvinyl alcohol site | part in a molecule | numerator, A well-known thing can be used. The polyvinyl alcohol part may be partially modified by acetalization, butyralization, carboxylation, or the like. In particular, polyvinyl alcohol partially carboxylated is preferable from the viewpoint of adhesion to a polymer film substrate.
The degree of polymerization of the polyvinyl alcohol resin is not particularly limited, but is usually 100 or more, preferably 300 to 40,000. The higher the degree of polymerization, the better the adhesion to the polymer film substrate, but the degree of polymerization is more preferably 3,000 or less because the viscosity of the coating solution is increased. Moreover, the balance of the adhesiveness with a polymer film base material and the viscosity of a coating liquid can also be adjusted by mixing 2 or more types of polyvinyl alcohol resin from which a polymerization degree differs.
The saponification degree of the polyvinyl alcohol resin is not particularly limited, but it is preferably 50 mol% or more, more preferably 60 to 100 mol%, still more preferably 70 to 99 mol%, and a polyvinyl acetate saponified product. Is used.

(Coating solution)
The liquid of the dispersion liquid of the coating liquid is not particularly limited as long as it can disperse the composite particles and the binder satisfactorily. From the viewpoint of application to in-line coating, an aqueous medium may be used. preferable. That is, the coating liquid is preferably a solution obtained by dissolving or dispersing composite particles, a binder, and other components added as necessary in an aqueous medium.

As the aqueous medium, water is preferable. In addition, amides such as N-vinylpyrrolidone, hexamethylphosphortriamide, N-vinylformamide, and N-vinylacetamide; phenols such as cresol, phenol, and xylenol; methanol , Ethanol, isopropyl alcohol, ethylene glycol, propylene glycol, dipropylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, diglycerin, isoprene glycol, butanediol, 1,5-pentanediol, 1,6- Alcohols such as hexanediol, 1,9-nonanediol and neopentyl glycol; ketones such as acetone; carbonates such as ethylene carbonate and propylene carbonate; dioxane and diethyl ether Ethers such as ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, propylene glycol dialkyl ether, polyethylene glycol dialkyl ether, polypropylene glycol dialkyl ether; heterocyclic compounds such as 3-methyl-2-oxazolidinone; acetonitrile, glutarodinitrile, methoxy Examples include nitriles such as acetonitrile, propionitrile, and benzonitrile. These may be used alone or in combination of two or more. Among these, it is preferable that water is included.
When preparing the coating liquid, when the composite particles are provided as a dispersion, a part or all of the liquid used in the dispersion can be used as it is, as described above.

  Additives other than the composite particles and the binder may be added to the coating liquid as long as the effects of the present invention are not impaired. Examples of the additive include a plasticizer for a resin as a binder, a wetting agent for improving wettability to a polymer film substrate, a thickener, an antifoaming agent, a crosslinking agent, an antioxidant, an ultraviolet absorber, Coloring agents, flame retardants, lubricants, preservatives and the like can be mentioned.

The mixing method of each component of the coating liquid is not particularly limited as long as a uniform coating liquid is obtained. For example, each component may be mixed in a state dissolved or dispersed in the aqueous medium, or each component other than the composite particles may be added to the composite particle dispersion. The order of adding each component is not particularly limited.
Any means may be used for mixing as long as the dispersion stability of each component is not impaired and a uniform coating solution can be obtained. For example, it can mix using apparatuses, such as a stirrer, a disper, a planetary mixer, and a rotation-revolution mixer.

[Coating layer forming step]
In this step, the polymer film substrate is coated with the coating solution and dried to form a coating layer. When the coating layer is subjected to a subsequent conductive film formation step, the coating layer may remain in a state of covering the polymer film substrate or may be peeled off from the polymer film substrate.

(Polymer film substrate)
The polymer film substrate has a coating layer formed on the surface thereof. In a later step, when the coating layer on the polymer film substrate is stretched together with the polymer film substrate, a stretchable resin is used. Is used. On the other hand, when the coating layer is peeled from the polymer film substrate and only the coating layer is stretched, a resin capable of peeling the coating layer is used.

As the stretchable resin, a thermoplastic resin is preferable. Further, a thermosetting resin or ultraviolet curable resin, an uncured or semi-cured thermosetting resin or ultraviolet curable resin, or the like can also be used in a mode of curing after stretching.
Examples of such resins include polyamide resins; polyolefin resins such as polyethylene and polypropylene; polyester resins such as polylactic acid, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polyethylene terephthalate isophthalate; polyacetal resins; polycarbonate resins; acrylates Resins; polystyrene resins; polyurethane resins, polyvinyl chloride resins; polyphenylene resins, fluororesins, and the like. These may be used alone or in combination of two or more. Of these, polyolefin resins and polyester resins are preferable, and among these, polyethylene, polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate are particularly preferable. The polymer film substrate may be a laminate composed of one or more of the above resins.
The polymer film substrate using these resins may be subjected to a surface treatment such as primer treatment or corona treatment from the viewpoint of preventing peeling of the coating layer during stretching.
Moreover, a well-known additive may be added to the polymer film base material. Examples of the additive include an antioxidant; a matting agent; a pigment; a filler such as silica, calcium carbonate, kaolin, and titanium dioxide; and an antistatic agent.

  Examples of the releasable resin include polyolefin resins similar to the stretchable resin described above, and fluororesins such as polytetrafluoroethylene. These may be used alone or in combination of two or more. May be. In addition, any resin can be used as long as it is a resin film subjected to a release treatment.

  The thickness of the polymer film substrate can be appropriately set according to the material of the polymer film substrate, the use of the conductive film, etc., but in either case of stretching with the coating layer or peeling of the coating layer In view of mechanical strength, handleability, etc., the thickness is preferably 5 to 300 μm, more preferably 7 to 250 μm, and still more preferably 10 to 200 μm.

(Formation of coating layer)
The method for coating the polymer film substrate with the coating liquid is not particularly limited, and a known method can be used. Examples thereof include a spray method, a flow coat method, a roll coat method, a gravure roll coat method, a knife coat method, a dip coat method, a comma coat method, a lip direct method, a slit reverse method, and a blade coat method. These coating methods may be performed once, or may be repeated a plurality of times.

And a coating layer is formed by drying the coating liquid on the coated polymer film base material. A coating layer having a desired thickness may be formed by repeating coating and drying of the coating solution a plurality of times.
From the viewpoint of efficiency, drying is preferably performed by heating within a range in which the composite particles constituting the coating layer, the binder resin, and the like do not cause thermal degradation. The drying conditions can be appropriately determined according to the boiling point, volatility, etc. of the dispersion medium of the coating liquid. It is preferable that drying temperature is 15-200 degreeC, More preferably, it is 30-170 degreeC, More preferably, it is 50-150 degreeC. You may dry under reduced pressure for efficiency. As the drying means, for example, a hot air drying furnace, an infrared drying furnace, a hot plate, or the like can be used.

  When the coating layer on the polymer film substrate is stretched together with the polymer film substrate in the subsequent conductive film formation step, the coating layer is preferably formed by in-line coating performed continuously with the step. . According to the in-line coating, it is possible to reduce the manufacturing equipment and suppress the manufacturing cost. In addition, the thickness of the conductive film can be adjusted by the stretching ratio.

[Conductive film forming step]
In this step, the coating layer is heated and stretched to form a conductive film. In the heat stretching, as described above, the coating layer on the polymer film substrate may be stretched together with the polymer film substrate. Alternatively, the coating layer is peeled off from the polymer film substrate and only the coating layer is removed. You may extend | stretch.

(Heat stretching)
The stretching method is not particularly limited, and can be appropriately selected depending on the material of the binder and the polymer film substrate, the application application and performance of the conductive film, and even if it is uniaxial stretching or biaxial stretching. May be.
The stretching temperature is set higher than the glass transition temperature of the polymer seed particles protected with a polyanion and is preferably 10 ° C. or higher, more preferably 15 ° C. or higher. It can suppress that the electrical conductivity of the electrically conductive film formed by extending | stretching falls because extending | stretching temperature is higher than the said glass transition temperature.
The upper limit of the absolute value of the temperature difference between the stretching temperature and the glass transition temperature is not particularly limited as long as the resin constituting the polymer seed particles is in a range that does not deteriorate due to heat stretching.
In the case where the coating layer is stretched together with the polymer film substrate, the stretching temperature is preferably equal to or higher than the glass transition temperature of the resin constituting the polymer film substrate, and more preferably a temperature higher by 10 ° C. than the glass transition temperature. More preferably, the temperature is 15 ° C. or more higher than the glass transition temperature.
Further, in both cases where the coating layer is stretched together with the polymer film substrate and only the coating layer is stretched, the composite particles constituting the coating layer, the resin of the binder, etc. are in a temperature range that does not deteriorate, 30 to It is preferable that it is 200 degreeC, More preferably, it is 40-170 degreeC, More preferably, it is 50-150 degreeC.
The stretching ratio is appropriately set according to the content of the composite particles, the thickness of the coating layer, the thickness of the desired conductive film, and the like, but is 110 to 2000% from the viewpoint of the mechanical strength and conductivity of the conductive film. It is preferable that it is preferably 115 to 1700%, and more preferably 120 to 1500%. In addition, let the extending | stretching rate be the value computed by a following formula about the length of an extending | stretching direction.
Stretch rate [%] = {(length after stretching−length before stretching) / length before stretching} × 100

[Conductive film]
Since the electrically conductive film obtained by the manufacturing method of this invention can comprise a composite particle and a binder with the material which has transparency, it can also be obtained as a transparent electrically conductive film. Therefore, the electrically conductive film of this invention can be used suitably as a transparent electrically conductive film in a touch panel, an organic electroluminescent element, a thin film solar cell etc., for example.
Moreover, the electrically conductive film and polymer film base material which were obtained by extending | stretching a coating layer with a polymer film base material are applicable as an antistatic film. That is, the manufacturing method of the electrically conductive film which concerns on this invention is applicable to the manufacturing method of the antistatic film which consists of an electrically conductive film and a polymer film base material.
In addition to the above, the conductive film of the present invention can be suitably applied to resin films and the like that require electrical conductivity and antistatic properties in the electrical / electronic field or other fields.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[Physical property measurement and evaluation method]
The measurement and evaluation methods for various physical properties in the following examples and comparative examples are as follows.
(1) Concentration of solid content Using an infrared moisture meter (FD-720, manufactured by Kett Scientific Laboratory Co., Ltd.), measurement was performed under conditions of a sample weight of 10 g and 110 ° C. for 30 minutes. The solid content concentration is a non-volatile content calculated by the following formula for a predetermined amount of sample.
Nonvolatile content [%] = (weight after drying / weight before drying) × 100
(2) pH
The pH of the dispersion was measured with a pH meter (HM-30G, manufactured by Toa DKK Corporation) at 25 ° C.
(3) Particle size of polymer seed particle (d50)
The particle size distribution of the polymer seed particles was measured with a Microtrac particle size analyzer (manufactured by Nikkiso Co., Ltd., Microtrac UPA), and the 50% median diameter d50 on a volume basis was determined.
(4) Glass transition temperature (Tg)
About 2 g of polymer seed particles were dried in a dryer at 110 ° C. for 1 hour, and the obtained dried product was pulverized in a mortar.
About 20 mg of the obtained pulverized product was weighed in an aluminum sample container for DSC, and heated at a rate of 20 ° C./min. Under a nitrogen gas atmosphere. And heated to 150 ° C. and held for 1 hour. Then, the sample was taken out from the DSC, the sample container was quickly covered and returned to the DSC, and cooled to 0 ° C. in 5 to 30 minutes using liquid nitrogen. In accordance with JIS K 7121: 2012, a heating rate of 20 ° C./min. The glass transition temperature (intermediate glass transition temperature) was measured.
(5) Thickness About the coating layer and the electrically conductive film, the thickness in arbitrary three places was measured with the micrometer, respectively, and these average values were made into the thickness in Table 1.
(6) Conductivity The surface resistance of the coating layer and the conductive film is measured with a simple low resistivity meter (Loresta GP MCP-T610, manufactured by Mitsubishi Chemical Corporation). Was used to calculate the conductivity.
Conductivity = 1 / (surface resistance x film thickness)
(7) Transparency The coating solution diluted 5 times was applied on a smooth transparent glass plate with a bar coater and dried at 80 ° C. for 10 minutes to form a coating film of about 100 nm. About this coating film, transparency was confirmed visually.

[Example 1]
(Preparation of dispersion liquid of polymer seed particles protected with polyanion)
86 g of styrene, 49 g of 2-ethylhexyl acrylate, 15 g of divinylbenzene and sodium polystyrene sulfonate (manufactured by Tosoh Organic Chemical Co., Ltd., Polynus PS-5, weight average molecular weight: about 120,000) and 500 g of a 22% by weight aqueous solution were mixed with stirring. A monomer mixture was prepared.
On the other hand, while stirring 1000 g of a 22% by weight aqueous solution of sodium polystyrenesulfonate (same as above), the temperature was raised to 80 ° C., and 2 g of potassium persulfate was added thereto.
To this solution, 40 g of the monomer mixture and potassium persulfate 2.5 mass% aqueous solution were added dropwise over 2 hours and 2.5 hours, respectively. After completion of dropping, the mixture was kept at 80 ° C. for 2 hours, and then cooled to room temperature (25 ° C.).
To the obtained reaction solution, 1500 ml of a cation exchange resin (manufactured by Organo Corporation, IR120B-H) and 1500 ml of an anion exchange resin (manufactured by Organo Corporation, IRA410-OH) were added and stirred for 12 hours, and then the ion exchange resin. Was filtered. Ion-exchanged water (hereinafter simply referred to as water) was added to adjust the solid content concentration to 15.0% by mass, and polymer seed particles protected with polyanion (Tg: 30 ° C., particle size) d50: 0.46 μm) was obtained.

(Preparation of composite particle-containing dispersion)
In a 1 L polyethylene container, 223.2 g of water, 31.5 g of a 12% by weight aqueous solution of sodium polystyrene sulfonate, and 34.0 g of a dispersion of polymer seed particles protected with a polyanion prepared above were stirred at 32 ° C. Mixed. To this mixed liquid, 2.80 g of 3,4-ethylenedioxythiophene was added at 32 ° C., and the mixture was emulsified and mixed for 30 minutes with a homomixer (Robomix; 4000 rpm, manufactured by Tokushu Kika Kogyo Co., Ltd.). A dispersion was prepared (sulfonic acid group content: 1.9 mol with respect to 1 mol of 3,4-ethylenedioxythiophene). The sulfonic acid group is derived from sodium polystyrene sulfonate in a 12% by weight aqueous solution of sodium polystyrene sulfonate and the dispersion.
The monomer dispersion is charged into a 1 L stainless steel container to which a high shear mixer (manufactured by Taiheiyo Kiko Co., Ltd., Milder 303V; 5000 rpm) and a circulation pump are connected, and circulated at 32 ° C. with a stirring blade and a high shear mixer. Then, 5.89 g of sodium peroxodisulfate and 6.88 g of a 1% by mass aqueous solution of iron (III) sulfate hexahydrate were added as an oxidizing agent, and a polymerization reaction was carried out for 24 hours.
221 g of the obtained reaction liquid and 79 g of water were put into a 1 L stainless steel container to which a high shear mixer (manufactured by IKA, Magic Lab; 1800 rpm) and a circulation pump were connected, stirred for 12 hours while circulating, and dispersed. Went.
To 300 g of the obtained dispersion, 300 mL of a cation exchange resin (same as above) and 300 mL of an anion exchange resin (same as above) were added and stirred for 6 hours, and then the ion exchange resin was filtered off. The monomer and oxidant were removed. A dispersion liquid (solid content concentration: 2.4% by mass) containing composite particles of polymer seed particles and a conjugated conductive polymer which were adjusted to pH 4.4 with aqueous ammonia and protected colloid with polyanion was obtained.

(Preparation of conductive film)
125.0 g of the composite particle-containing dispersion (2.4% by mass solid content) prepared above, polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA217, degree of saponification: about 87 to 89 mol%, degree of polymerization: about 1,700 ) 30.0 g of 15% by weight aqueous solution, 5.0 g of ethylene glycol, 4.5 g of glycerin, 23.0 g of water, 0.2 g of an antifoaming agent (manufactured by San Nopco Co., Ltd., Nopco 1407-H) are stirred and mixed to form a coating solution ( A solid content concentration of 4.0% by mass and a composite particle content of 40% by mass in the solid content) were prepared.
In addition, when the transparency of the coating film of a coating liquid was evaluated by the method mentioned above, it was confirmed that it was transparent.
This coating solution is poured into a 7 cm × 17 cm mold on a smooth polyethylene film substrate, dried at 23 ° C. and 50% relative humidity for 2 days, and at 80 ° C. for 1 hour to form a coating layer. It peeled.
The coating layer was cut into 15 mm × 45 mm, and fixed to a precision universal testing machine (manufactured by Shimadzu Corporation, Autograph AG-X, 20 kN) in a 85 ° C. constant temperature bath with a distance between chucks of 15 mm. After holding for 3 minutes in a thermostatic bath and confirming that the surface of the coating layer reached 80 ° C. (stretching temperature), the stretching speed was 30 mm / min. The film was stretched by about 400% to prepare a conductive film.
The thickness and conductivity of the coating layer and the conductive film are shown in Table 1 below. In this example, the electrical conductivity of the conductive film was evaluated only with the conductive film (coating layer) from the viewpoint of eliminating the influence of the base material.

[Examples 2 to 4, Comparative Examples 1 to 3]
In Example 1, styrene, 2-ethylhexyl acrylate and divinylbenzene in the monomer mixture for obtaining a dispersion of polymer seed particles in Example 1 were changed to the composition shown in Table 1 below, and the coating liquid was changed to Table 1 below. In the same manner as in Example 1, a coating layer and a conductive film were produced.
Table 1 below shows the film thickness and conductivity of these coating layers and conductive films.
In addition, when the transparency of the coating film of each coating liquid was evaluated by the method described above, it was confirmed to be transparent.

  About each coating layer produced by the said Example and comparative example, the thickness and electrical conductivity of the electrically conductive film extended | stretched by the predetermined extending | stretching rate are measured, and a coating layer (electrically conductive film before extending | stretching) is set to 100 [%] The change in conductivity ratio was determined. These results are shown in Table 2 below, and the relationship between the stretch ratio and the thickness is shown as a graph in FIGS. 1 to 3 for each of the same composite particle content in the solid content of the coating liquid.

  As can be seen from the graphs shown in Tables 1 and 2 and FIGS. 1 to 3, when the glass transition temperature of the polymer seed particles is lower than the stretching temperature 80 ° C. in the heat stretching (Examples 1 to 4), It was observed that the decrease in conductivity was suppressed.

Claims (15)

Preparing a coating liquid containing composite particles of a polymer seed particle protected with a polyanion and a conjugated conductive polymer, and a binder, and a binder;
Coating the polymer film substrate with the coating solution and drying to form a coating layer;
Heating and stretching the coating layer to form a conductive film,
A method for producing a conductive film, wherein a glass transition temperature of the protective colloidal polymer seed particles is lower than a stretching temperature in the heat stretching.   The method for producing a conductive film according to claim 1, wherein the glass transition temperature is 10 ° C. or more lower than the stretching temperature.   The manufacturing method of the electrically conductive film of Claim 1 or 2 which the said polymer seed particle consists of a polymer which contains 1 type, or 2 or more types of ethylenically unsaturated monomers as a structural unit.   The manufacturing method of the electrically conductive film of any one of Claims 1-3 whose content of the said composite particle in solid content of the said coating liquid is 1-70 mass%.   The manufacturing method of the electrically conductive film of any one of Claims 1-4 with which the said composite particle is provided as a dispersion liquid in the process of preparing the said coating liquid.   The manufacturing method of the electrically conductive film of any one of Claims 1-5 whose said binder is a thermoplastic resin.   The binder is one selected from polyester resin, acrylic resin, polyurethane resin, polyvinyl alcohol resin, polyamide resin, polyimide resin, vinyl ester resin, polystyrene resin, polyvinyl chloride resin, polyolefin resin, polycarbonate resin, and cellulose resin. It is the above, The manufacturing method of the electrically conductive film of any one of Claims 1-6.   The monomer that is a constituent unit of the conjugated conductive copolymer is selected from pyrrole which may have a substituent, aniline which may have a substituent, and thiophene which may have a substituent. The manufacturing method of the electrically conductive film of any one of Claims 1-7 containing 1 or more types. The manufacturing method of the electrically conductive film of any one of Claims 1-8 in which the monomer which is a structural unit of the said conjugated system conductive copolymer contains the compound represented by following formula (1).

(In Formula (1), R ¹ and R ² are each independently a hydrogen atom, a hydroxyl group, an optionally substituted alkyl group having 1 to 18 carbon atoms, or an optionally substituted carbon number. Any one of 1 to 18 alkoxy groups, an optionally substituted alkylthio group having 1 to 18 carbon atoms, or a substituent in which R ¹ and R ² are bonded to each other to form a ring; An alicyclic ring having 3 to 10 carbon atoms, an aromatic ring having 6 to 10 carbon atoms that may have a substituent, and an oxygen atom-containing complex having 3 to 10 ring members that may have a substituent A ring, a sulfur atom-containing heterocycle having 3 to 10 ring members that may have a substituent, or a sulfur atom and oxygen atom-containing heterocycle having 3 to 10 ring members that may have a substituent.   The manufacturing method of the electrically conductive film of any one of Claims 1-9 which is a polymer in which the said polyanion has group which consists of a sulfonic acid or its salt.   The content of an anionic group in the polyanion is 0.25 to 30 mol with respect to 1 mol of a monomer that is a constituent unit of the conjugated conductive copolymer, or any one of claims 1 to 10. The manufacturing method of the electrically conductive film of Claim 1.   The manufacturing method of the electrically conductive film of any one of Claims 1-11 whose said electrically conductive film is a transparent conductive film.   The method for producing a conductive film according to any one of claims 1 to 12, wherein, in the heat stretching, after the coating layer is peeled from the polymer film substrate, only the coating layer is stretched.   The manufacturing method of the electrically conductive film of any one of Claims 1-12 which extends | stretches the said coating layer on the said polymer film base material with this polymer film base material in the said heat extending | stretching.   15. A method for producing an antistatic film, comprising: obtaining an antistatic film comprising the conductive film and the polymer film substrate by the production method according to claim 14. .