JP7341029B2 - Conductive release film and its manufacturing method - Google Patents

Description

The present invention relates to a conductive polymer dispersion, a conductive film, and a method for manufacturing the same, and a conductive release film and a method for manufacturing the same.

BACKGROUND OF THE INVENTION As a technique for manufacturing electronic devices, it is required to form a conductive layer on the surface of a plastic base material. π-conjugated conductive polymers are attracting attention as materials for forming conductive layers because they have excellent conductivity and transparency.
As a method for forming a conductive layer containing a π-conjugated conductive polymer, for example, a conductive polymer dispersion in which a conductive composite containing a π-conjugated conductive polymer and a polyanion is dispersed in water is used. Examples include a method of coating on a base material and drying it (Patent Document 1).

International Publication No. 2015/108001

The surface of a plastic base material is usually hydrophobic unless it is subjected to a hydrophilic treatment. Therefore, a conductive layer formed by coating a plastic base material with an aqueous conductive polymer dispersion described in Patent Document 1 and the like tends to have low adhesion (adhesiveness) to the base material.
The present inventors investigated the production of a laminate in which a release layer containing a silicone compound was further laminated on the surface of a conductive layer formed on the surface of a resin base material. At this time, the conductive layer is required to have both high adhesion to the resin base material and high adhesion to the laminated release layer.

The present invention provides a conductive release film laminated in the order of film base material/conductive layer/release layer made of plastic, which has excellent adhesion to both the film base material and the release layer. Provided are a conductive polymer dispersion capable of forming a layer, a conductive film using the same, and a method for producing the same, and a conductive release film and a method for producing the same.

[1] A conductive polymer dispersion containing a conductive composite containing a π-conjugated conductive polymer and a polyanion, a water-dispersible resin having a glass transition point of 52° C. or higher and 64° C. or lower, and a dispersion medium. liquid.
[2] The conductive polymer dispersion according to [1], wherein the water-dispersible resin has a glass transition point of 60°C or more and 64°C or less.
[3] The conductive polymer dispersion according to [1] or [2], wherein the water-dispersible resin is a water-dispersible polyester resin.
[4] The conductive polymer dispersion according to any one of [1] to [3], further containing a glycidyl group-containing acrylic resin.
[5] The conductive polymer dispersion according to any one of [1] to [4], wherein the dispersion medium contains a monohydric alcohol.
[6] The conductive polymer dispersion according to [5], wherein the monohydric alcohol contains methanol.
[7] The conductive polymer dispersion according to any one of [1] to [6], further containing a highly conductive agent.
[8] The conductive polymer dispersion according to [7], wherein the high conductivity agent contains a dihydric alcohol.
[9] The conductive polymer dispersion according to [7] or [8], wherein the high conductivity agent contains propylene glycol.
[10] The conductive polymer dispersion according to any one of [1] to [9], wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene).
[11] The conductive polymer dispersion according to any one of [1] to [10], wherein the polyanion is polystyrene sulfonic acid.
[12] A conductive layer comprising a film base material and a cured layer of the conductive polymer dispersion according to any one of [1] to [11], formed on at least one surface of the film base material. A conductive film comprising:
[13] The conductive film according to [12], wherein the film base material is formed of a polyester resin.
[14] A conductive layer comprising a film base material and a cured layer of the conductive polymer dispersion according to any one of [1] to [11], formed on at least one surface of the film base material. and a release layer containing a silicone compound, which is laminated on the surface of the conductive layer.
[15] Apply the conductive polymer dispersion according to any one of [1] to [11] to at least one surface of the film base material, dry the formed coating film, and form a conductive layer. A method for producing a conductive film, comprising:
[16] Apply the conductive polymer dispersion according to any one of [1] to [11] to at least one surface of the film base material, dry the formed coating film, and form a conductive layer. and applying a mold release agent composition containing a silicone-based compound to the surface of the conductive layer and drying the formed coating film to form a mold release layer. manufacturing method.
[17] The method for producing a conductive release film according to [16], wherein the silicone compound is an addition-curing silicone resin.

By using the conductive polymer dispersion of the present invention, a conductive layer with excellent adhesion to a plastic substrate and a release layer can be formed.
In the conductive film of the present invention, the conductive layer has high adhesion to the film base material.
In the conductive release film of the present invention, the adhesion of the conductive layer to the film base material is high, and the adhesion of the release layer to the conductive layer is also sufficient, and the surface of the release layer has good release properties. Demonstrate type.
Each manufacturing method of the present invention can easily manufacture a conductive film and a conductive release film.

<Conductive polymer dispersion>
A first aspect of the present invention includes a conductive composite containing a π-conjugated conductive polymer and a polyanion, a water-dispersible resin having a glass transition point of 52° C. or higher and 64° C. or lower, and a dispersion medium. It is a conductive polymer dispersion liquid.

[Conductive composite]
The conductive composite contained in the conductive polymer dispersion of this embodiment includes a π-conjugated conductive polymer and a polyanion. The polyanion in the conductive composite is doped into a π-conjugated conductive polymer to form a conductive composite having conductivity.
In the polyanion, only some anion groups are doped into the π-conjugated conductive polymer, and there are surplus anion groups that do not participate in doping. Since the excess anion group is a hydrophilic group, the conductive composite has water dispersibility.

(π-conjugated conductive polymer)
The π-conjugated conductive polymer may be any organic polymer whose main chain is composed of a π-conjugated system, such as polypyrrole-based conductive polymers, polythiophene-based conductive polymers, and polyacetylene-based conductive polymers. Examples include polyphenylene conductive polymers, polyphenylene vinylene conductive polymers, polyaniline conductive polymers, polyacene conductive polymers, polythiophene vinylene conductive polymers, and copolymers thereof. From the viewpoint of stability in air, polypyrrole-based conductive polymers, polythiophenes, and polyaniline-based conductive polymers are preferred, and from the viewpoint of transparency, polythiophene-based conductive polymers are more preferred.

Polythiophene-based conductive polymers include polythiophene, poly(3-methylthiophene), poly(3-ethylthiophene), poly(3-propylthiophene), poly(3-butylthiophene), poly(3-hexylthiophene). , poly(3-heptylthiophene), poly(3-octylthiophene), poly(3-decylthiophene), poly(3-dodecylthiophene), poly(3-octadecylthiophene), poly(3-bromothiophene), poly (3-chlorothiophene), 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-decyloxythiophene) ,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-carboxythiophene) butylthiophene).
Examples of polypyrrole-based conductive polymers include polypyrrole, poly(N-methylpyrrole), poly(3-methylpyrrole), poly(3-ethylpyrrole), poly(3-n-propylpyrrole), and poly(3-butylpyrrole). pyrrole), poly(3-octylpyrrole), poly(3-decylpyrrole), poly(3-dodecylpyrrole), poly(3,4-dimethylpyrrole), poly(3,4-dibutylpyrrole), poly(3-dibutylpyrrole) -carboxypyrrole), poly(3-methyl-4-carboxypyrrole), poly(3-methyl-4-carboxyethylpyrrole), poly(3-methyl-4-carboxybutylpyrrole), poly(3-hydroxypyrrole) , poly(3-methoxypyrrole), poly(3-ethoxypyrrole), poly(3-butoxypyrrole), poly(3-hexyloxypyrrole), and poly(3-methyl-4-hexyloxypyrrole).
Examples of polyaniline-based conductive polymers include polyaniline, poly(2-methylaniline), poly(3-isobutylaniline), poly(2-aniline sulfonic acid), and poly(3-aniline sulfonic acid).
Among these π-conjugated conductive polymers, poly(3,4-ethylenedioxythiophene) is particularly preferred in terms of conductivity, transparency, and heat resistance.
The number of types of π-conjugated conductive polymers contained in the conductive composite may be one or two or more types.

(Polyanion)
A polyanion is a polymer having two or more monomer units having anionic groups in its molecule. The anion group of this polyanion functions as a dopant for the π-conjugated conductive polymer to improve the conductivity of the π-conjugated conductive polymer.
The anion group of the polyanion is preferably a sulfo group or a carboxy group.
Specific examples of such polyanions include polystyrene sulfonic acid, polyvinyl sulfonic acid, polyallylsulfonic acid, polyacrylic ester having a sulfo group, polymethacrylic ester having a sulfo group (for example, poly(4-sulfobutyl methacrylate) , polysulfoethyl methacrylate, polymethacryloyloxybenzenesulfonic acid), poly(2-acrylamido-2-methylpropanesulfonic acid), polyisoprene sulfonic acid, and other polymers with sulfo groups, polyvinylcarboxylic acid, polystyrenecarboxylic acid, Polymers having carboxyl groups such as polyarylcarboxylic acid, polyacrylic acid, polymethacrylic acid, poly(2-acrylamido-2-methylpropanecarboxylic acid), and polyisoprenecarboxylic acid are mentioned. may be a homopolymer obtained by polymerizing two or more types of monomers, or a copolymer obtained by polymerizing two or more types of monomers.
Among these polyanions, polymers having sulfo groups are preferred, and polystyrene sulfonic acid is more preferred, since it can further increase the conductivity.
The polyanions may be used alone or in combination of two or more.
The mass average molecular weight of the polyanion is preferably 20,000 or more and 1,000,000 or less, more preferably 100,000 or more and 500,000 or less. The mass average molecular weight is a mass-based average molecular weight measured using gel permeation chromatography and calculated in terms of polystyrene.

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

The content of the conductive composite contained in the conductive polymer dispersion of this embodiment is preferably 0.01% by mass or more and 1% by mass or less, and 0.01% by mass or more and 1% by mass or less, based on the total mass of the conductive polymer dispersion. 02% by mass or more and 0.5% by mass or less, more preferably 0.03% by mass or more and 0.1% by mass or less.
When it is at least the lower limit of the above range, the conductivity of the conductive layer formed by applying the conductive polymer dispersion can be further improved.
When it is below the upper limit of the above range, the dispersibility of the conductive composite in the conductive polymer dispersion can be improved and a uniform conductive layer can be formed.

[Water dispersible resin]
The water-dispersible resin can function as a binder resin in the conductive layer formed from the coating film of the conductive polymer dispersion of this embodiment.
A water-dispersible resin is a resin that can be dispersed or dissolved in a dispersion medium containing water. In the conductive polymer dispersion of this embodiment, the state of the water-dispersible resin may be a dispersed state dispersed by homogenization or the like, an emulsion state, or a dissolved state.
The water-dispersible resin is preferably a resin having a functional group that can be dissociated in water, such as an acid group such as a carboxy group or a sulfo group, or a salt thereof. Specifically, preferred are acrylic resins, polyester resins, polyurethane resins, polyimide resins, and melamine resins, and water-dispersible resins having an acid group such as a carboxyl group or a sulfo group or a salt thereof.
Among the above-mentioned water-dispersible resins, polyester resins, urethane resins, and acrylic resins are preferable because the adhesion of the conductive layer to the base material and the release layer is further improved. In particular, when the base film is a polyester resin, the water-dispersible resin is preferably a polyester resin.
The number of water-dispersible resins contained in the conductive polymer dispersion of this embodiment may be one type or two or more types.

The glass transition point (Tg) of the water-dispersible resin contained in the conductive polymer dispersion of this embodiment is 52°C or more and 64°C or less, preferably 60°C or more and 64°C or less. Here, the glass transition point is a value measured based on JIS K7121:2012.
When the glass transition point of the water-dispersible resin is within the above range, the adhesion of the conductive layer to the base material will be improved.

In the conductive polymer dispersion of this aspect, the content of the water-dispersible resin relative to 100 parts by mass of the conductive composite is preferably 100 parts by mass or more and 10,000 parts by mass or less, and 500 parts by mass or more and 5,000 parts by mass or less. More preferably, it is 1000 parts by mass or more and 2000 parts by mass or less. Within the above-mentioned suitable range, the adhesion of the conductive layer to the film base material can be improved, and good conductivity of the conductive layer can be ensured.

[Dispersion medium]
Examples of the dispersion medium contained in the conductive polymer dispersion of this embodiment include water, an organic solvent, and a mixture of water and an organic solvent.
Examples of the organic solvent include alcohol solvents, ether solvents, ketone solvents, ester solvents, and aromatic hydrocarbon solvents.
Examples of alcoholic solvents include methanol, ethanol, 1-propanol, 2-propanol, 2-methyl-2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, allyl alcohol, propylene glycol monomethyl Examples include monohydric alcohols such as ether and ethylene glycol monomethyl ether.
Examples of the ether solvent include diethyl ether, dimethyl ether, ethylene glycol, propylene glycol, and propylene glycol dialkyl ether.
Examples of the ketone solvent include diethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, methyl amyl ketone, diisopropyl ketone, methyl ethyl ketone, acetone, diacetone alcohol, and the like.
Examples of the ester solvent include ethyl acetate, propyl acetate, butyl acetate, and the like.
Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene, ethylbenzene, propylbenzene, and isopropylbenzene.
One type of organic solvent may be used alone, or two or more types may be used in combination.
Among the organic solvents, monohydric alcohol is preferable, and methanol is more preferable because it can further improve the dispersibility of the conductive composite, the carboxy group-containing polyolefin resin, and the polyester resin.

Since the conductive composite has high dispersibility in water, the dispersion medium of the conductive polymer dispersion of this embodiment is preferably an aqueous dispersion medium containing water.
The content ratio of water to the total dispersion medium contained in the conductive polymer dispersion of this embodiment can be, for example, 5% by mass or more and 100% by mass or less, preferably 10% by mass or more and 50% by mass or less, and 20% by mass. % or more and 40% by mass or less is more preferable. As the dispersion medium other than water, monohydric alcohol is preferred. Note that among the high conductivity agents described below, the mass of those that fall under the examples of the organic solvents mentioned above shall be included in the mass of the total dispersion medium.

In the conductive polymer dispersion of this embodiment, the water-dispersible resin is preferably in a state of being dispersed in an aqueous dispersion medium. In such a dispersion state, the characteristics of the conductive layer obtained by applying the conductive polymer dispersion to the film base material will be uniform over the entire surface of the conductive layer, and the conductivity to the film base material and release layer will be uniform. This is preferred because the adhesion of the layer is further improved.

[High conductivity agent]
The conductive polymer dispersion of this embodiment may contain a high conductivity agent in order to further improve conductivity. Here, the π-conjugated conductive polymer, the polyanion, the water-dispersible resin described above, and the binder component are not classified as high-conductivity agents.
The high conductivity agent is a saccharide, a nitrogen-containing aromatic cyclic compound, a compound having two or more hydroxy groups, a compound having one or more hydroxy groups and one or more carboxy group, a compound having an amide group, Preferably, it is at least one compound selected from the group consisting of imide group-containing compounds, lactam compounds, and glycidyl group-containing compounds.
The number of highly conductive agents contained in the conductive polymer dispersion of this embodiment may be one type, or two or more types.

The content ratio of the high conductivity agent in the conductive polymer dispersion of this embodiment is preferably 1 part by mass or more and 100,000 parts by mass or less, and 10 parts by mass or more and 10,000 parts by mass or less, based on 100 parts by mass of the conductive composite. It is more preferably 500 parts by mass or more and 9000 parts by mass or less. If the content ratio of the high conductivity agent is above the lower limit value, the conductivity improvement effect by adding the high conductivity agent will be fully exhibited, and if it is below the upper limit value, the concentration of π-conjugated conductive polymer will be reduced. It is possible to prevent a decrease in conductivity caused by

[Other binder components]
The conductive polymer dispersion of this embodiment may contain a binder component other than the water-dispersible resin.
Specific examples of the binder component include binder resins such as acrylic resin, epoxy resin, oxetane resin, polyurethane resin, polyimide resin, melamine resin, silicone resin, and vinyl acetate resin.
Examples of the acrylic resin include glycidyl group-containing acrylic resins. The glycidyl group-containing acrylic resin is an acrylic resin having a glycidyl group. Specifically, for example, a homopolymer of a monomer having a glycidyl group and an acryloyloxy group or a methacryloyloxy group, a copolymer of the monomer and a monomer having another radically polymerizable unsaturated group that can be copolymerized therewith. One example is merging.
Further, the binder component may be a monomer or oligomer forming the binder resin. At the time of forming the conductive layer, a binder resin can be formed by polymerizing the monomer or the oligomer.
The binder components may be used alone or in combination of two or more.

[Other additives]
The conductive polymer dispersion of this embodiment may contain other additives.
The additives are not particularly limited as long as the effects of the present invention can be obtained, and for example, surfactants, inorganic conductive agents, antifoaming agents, coupling agents, antioxidants, ultraviolet absorbers, etc. can be used. However, the additives are composed of compounds other than the aforementioned π-conjugated conductive polymer, polyanion, water-dispersible resin, dispersion medium, binder component, and high-conductivity agent.
Examples of the surfactant include nonionic, anionic, and cationic surfactants, and nonionic surfactants are preferred from the viewpoint of storage stability. Additionally, a polymeric surfactant such as polyvinylpyrrolidone may be added.
Examples of the inorganic conductive agent include metal ions, conductive carbon, and the like. Note that metal ions can be generated by dissolving metal salts in water.
Examples of antifoaming agents include silicone resins, polydimethylsiloxanes, silicone oils, and the like.
Examples of the coupling agent include silane coupling agents having an epoxy group, a vinyl group, or an amino group.
Examples of the antioxidant include phenolic antioxidants, amine antioxidants, phosphorus antioxidants, sulfur antioxidants, sugars, 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, benzoate UV absorbers, etc. can be mentioned.
When the conductive polymer dispersion liquid contains the above-mentioned additive, the content ratio is appropriately determined depending on the type of additive, but for example, 0.001 parts by mass per 100 parts by mass of the conductive composite. The content may be in a range of 5 parts by mass or less.

<Method for producing conductive polymer dispersion>
Examples of the method for producing the conductive polymer dispersion of this embodiment include a method of adding a water-dispersible resin, a dispersion medium, etc. to an aqueous dispersion of a conductive composite.
The aqueous dispersion of the conductive composite may be obtained by chemical oxidative polymerization of a monomer that forms a π-conjugated conductive polymer in an aqueous solution of a polyanion, or a commercially available dispersion may be used.

The chemical oxidative polymerization can be performed using a known catalyst and oxidizing agent. Examples of the catalyst include transition metal compounds such as ferric chloride, ferric sulfate, ferric nitrate, and cupric chloride. Examples of the oxidizing agent include persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate. The oxidizing agent can return the reduced catalyst to its original oxidized state.

(effect)
Conductive polymer dispersions containing π-conjugated conductive polymers are often aqueous dispersions due to their manufacturing method, and have low wettability to plastic substrates. Therefore, there has been a problem in that the adhesion of a conductive layer formed from a conventional conductive polymer dispersion to a plastic substrate is low.
Since the conductive polymer dispersion according to the present invention contains a water-dispersible resin having a Tg within a specific range, it is possible to form a conductive layer with excellent adhesion to a plastic substrate. Although the details of this mechanism are not yet clear, it is presumed that the water-dispersible resin contained in the conductive layer has the relevant Tg and thus tends to exert a physical anchoring effect on the surface of the plastic base material. . In particular, when the type of water-dispersible resin and the type of resin constituting the plastic base material are the same, the chemical affinity at the interface between the conductive layer and the plastic base material is high, and the above-mentioned physical anchor In addition to the effectiveness, chemical affinity is increased, resulting in significantly improved adhesion.
Further, the adhesion of the conductive layer formed from the conductive polymer dispersion according to the present invention is excellent not only to the film base material but also to another layer formed on the conductive layer. Therefore, for example, a release layer containing silicone may be formed on the conductive layer.

<Conductive film>
A second aspect of the present invention provides a conductive material comprising a film base material and a conductive layer formed on at least one surface of the film base material and comprising a hardened layer of the conductive polymer dispersion liquid of the first aspect. It's a film.

(conductive layer)
The average thickness of the conductive layer provided on at least one surface of the film base material is, for example, preferably 10 nm or more and 5000 nm or less, more preferably 20 nm or more and 1000 nm or less, and 30 nm or more and 500 nm or less. It is even more preferable.
If the average thickness of the conductive layer is equal to or greater than the lower limit, sufficiently high conductivity can be exhibited, and if the average thickness is equal to or less than the upper limit, the adhesion of the conductive layer is further improved.

The conductive layer of the conductive film of this embodiment preferably has a surface resistance value of, for example, 1×10 ² Ω/□ or more and 1×10 ¹⁰ Ω/□ or less, as a measure of good conductivity. It is more preferable to have a surface resistance value of ⁵ Ω/□ or more and 1×10 ⁹ Ω/□ or less, and more preferably a surface resistance value of 1×10 ⁶ Ω/□ or more and 1×10 ⁸ Ω/□ or less.

(Film base material)
Examples of the film base material include plastic films.
Examples of film base resins constituting plastic films include ethylene-methyl methacrylate copolymer resin, ethylene-vinyl acetate copolymer resin, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinyl alcohol, polyethylene terephthalate, and polybutylene terephthalate. , polyethylene naphthalate, polyacrylate, polycarbonate, polyvinylidene fluoride, polyarylate, styrene elastomer, polyester elastomer, polyether sulfone, polyetherimide, polyether ether ketone, polyphenylene sulfide, polyimide, cellulose triacetate, cellulose acetate propio Examples include Nate.
From the viewpoint of improving the adhesion between the film base material and the conductive layer, the resin for the film base material is preferably the same type of resin as the water-dispersible resin, and polyester resins such as polyethylene terephthalate are particularly preferred.

The resin for the film base material may be amorphous or crystalline.
The film base material may be unstretched or stretched.
The film base material may be subjected to surface treatment such as corona discharge treatment, plasma treatment, flame treatment, etc. in order to further improve the adhesion of the conductive layer formed from the conductive polymer dispersion.

The average thickness of the film base material is preferably 5 μm or more and 500 μm or less, more preferably 20 μm or more and 200 μm or less. If the average thickness of the film base material is greater than or equal to the lower limit, it will be difficult to break, and if it is less than or equal to the upper limit, sufficient flexibility can be ensured as a film.
The thickness of a member in this specification is a value obtained by measuring the thickness at arbitrary 10 locations and averaging the measured values.

A known polarizing film can also be used as the film base material.
As a polarizing film, for example, one including a pair of transparent films and a polarizing layer disposed between them is known.
Examples of the transparent resin constituting the transparent film include triacetyl cellulose, polyethylene terephthalate, polycarbonate, polycycloolefin, polystyrene, polyvinyl alcohol, and acrylic resin.
The thickness of the transparent film can be, for example, 10 μm or more and 500 μm or less, and preferably 20 μm or more and 300 μm or less in terms of achieving both thinness and strength.
Examples of the polarizing layer include those in which a dichroic substance is attached to a hydrophilic film and uniaxially stretched to orient the dichroic substance. Examples of the hydrophilic film include a polyvinyl alcohol film and a partially saponified film of ethylene/vinyl acetate copolymer. Examples of dichroic substances include iodine and dichroic dyes.
The thickness of the polarizing layer can be, for example, 10 μm or more and 500 μm or less, and preferably 20 μm or more and 300 μm or less in terms of achieving both thinness and polarization.

When the conductive film is used for optical purposes, it is preferable that the film base material is transparent. Specifically, the total light transmittance of the film base material is preferably 65% or more, more preferably 70% or more, and even more preferably 80% or more. The total light transmittance is a value measured according to JIS K7136.

<Method for manufacturing conductive film>
A third aspect of the present invention includes applying the conductive polymer dispersion of the first aspect to at least one surface of a film base material, drying the formed coating film, and forming a conductive layer. This is a method for producing a sex film. By the manufacturing method of this aspect, the conductive film of the second aspect can be manufactured.

Examples of the method for coating (coating) the conductive polymer dispersion of the first embodiment on a film base material include a gravure coater, a roll coater, a curtain flow coater, a spin coater, a bar coater, a reverse coater, a kiss coater, and a fountain coater. , a method using a coater such as a rod coater, an air doctor coater, a knife coater, a blade coater, a cast coater, a screen coater, a method using a sprayer such as air spray, airless spray, rotor dampening, an immersion method such as dipping, etc. can be applied.
Commercially available bar coaters are numbered according to the coating thickness, and the higher the number, the thicker the coating can be applied.
The amount of the conductive polymer dispersion applied to the film base material is not particularly limited, but in consideration of uniform and even coating, conductivity and film strength, the solid content should be 0.01 g/m ² It is preferably in the range of 10.0 g/m ² or less.

A conductive film in which a conductive layer (conductive film) is formed by curing the coating film by drying a coating film made of a conductive polymer dispersion coated on a film base material and removing the dispersion medium. A transparent film can be obtained.
Examples of methods for drying the coating film include heating drying, vacuum drying, and the like. For heating and drying, for example, a conventional method such as hot air heating or infrared heating can be used.
When heat drying is applied, the heating temperature is appropriately set depending on the dispersion medium used, but is usually within the range of 50°C or higher and 150°C or lower. Here, the heating temperature is the set temperature of the drying device.

When the applied conductive polymer dispersion contains a thermosetting monomer or oligomer as a binder component, the conductive layer is formed by heating the coating film and curing the binder component. You can get the film.
When the applied conductive polymer dispersion contains a photocurable monomer or oligomer as a binder component, the conductive layer can be cured by irradiating the coating film with ultraviolet rays or electron beams to harden the binder component. A formed conductive film can be obtained.

<Conductive release film>
A fourth aspect of the present invention includes a film base material, a conductive layer formed on at least one surface of the film base material, and comprising a hardened layer of the conductive polymer dispersion according to the first aspect; This is an electrically conductive release film that includes a release layer containing a silicone compound and laminated on the surface.
The conductive release film of this embodiment can have the same structure as the conductive film of the second embodiment except that it includes the release layer. Therefore, the explanation that overlaps with the explanation of the second aspect will be omitted.

(Release layer)
The release layer included in the conductive release film of this embodiment can have the same configuration as the release layer included in known release films. The silicone compound contained in the release layer contributes to exhibiting release properties (easy peelability).

As the silicone compound, a silicone compound known as a mold release agent is applied. Here, silicone is a polymer collectively referred to as organopolysiloxane, which has a main chain (silicone skeleton) in which an organic group (for example, an alkyl group or a phenyl group) is bonded to a siloxane bond. As the organopolysiloxane, polydimethylsiloxane (PDMS) is preferable, and polydimethylsiloxane partially having a reactive functional group or a non-reactive functional group is also preferable. Furthermore, acrylic resins and alkyd resins having organopolysiloxane in their side chains can also be used as the silicone compound.

As the silicone compound contained in the release layer of this embodiment, a cured product of curable silicone is preferable because it exhibits stable release properties and excellent film forming properties during production.
The curable silicone may be either an addition-curing silicone or a condensation-curing silicone. When curable silicone reacts, it forms a three-dimensional crosslinked structure and cures.
Examples of addition-curable silicones include linear polymers having siloxane bonds, including polydimethylsiloxane having vinyl groups at both ends of the linear chain, and hydrogen silane. A platinum-based curing catalyst may be used to accelerate curing.
Specific examples of addition-curing silicones include KS-3703T, KS-847T, KM-3951, X-52-151, X-52-6068, and X-52-6069 (manufactured by Shin-Etsu Chemical Co., Ltd.). .
Addition-curing silicones that are dissolved or dispersed in organic solvents are preferably used.

The content of the silicone compound contained in the release layer of this embodiment can be, for example, 20% by mass or more and 100% by mass, and 80% by mass or more and 100% by mass or less, based on the total mass of the release layer. A range of is preferred.
The release layer of this embodiment may contain a binder component other than a silicone compound or a binder component for improving adhesion, as long as the adhesion of the conductive layer to the release layer is not impaired and the release properties of the release layer are not impaired. It may also contain known additives such as antistatic agents and antistatic agents.

The average thickness of the release layer is, for example, preferably 10 nm or more and 50 μm or less, more preferably 20 nm or more and 20 μm or less.
If the average thickness of the release layer is equal to or greater than the lower limit value, higher mold release properties can be exhibited, and if it is equal to or less than the upper limit value, the adhesiveness to the conductive layer is further improved.

The release layer of the conductive release film of this embodiment may cover the entire surface of the conductive layer, or may cover only a portion of the conductive layer, with the remainder of the conductive layer exposed on the surface.

(effect)
Since the conductive layer of the conductive release film according to the present invention contains a water-dispersible resin having a Tg within a specific range, it can exhibit sufficient adhesion (adhesion) even to a release layer containing silicone. .
As a result, the release layer included in the conductive release film of the present invention can exhibit excellent release properties for objects attached to the release layer without peeling off from the main body of the conductive film. .
The release layer included in the conductive release film according to the present invention is basically an insulating layer. Therefore, the surface where the conductive layer is not exposed due to being covered by the release layer does not exhibit conductivity. However, even if the conductive layer is not exposed on the surface, if the conductive layer is exposed on the side (cross section) of the conductive release film, it is possible to electrically connect the exposed part to the outside. be. Further, even without taking any special measures, the presence of the conductive layer inside the conductive release film makes it possible to prevent the conductive release film itself from being charged.

<Method for manufacturing conductive release film>
A fifth aspect of the present invention is to apply the conductive polymer dispersion of the first aspect to at least one surface of a film base material, dry the formed coating film, and form a conductive layer (conductive layer formation). step), and applying a mold release agent composition containing a silicone compound to the surface of the conductive layer, drying the formed coating film, and forming a mold release layer (mold release layer forming step). A method for producing a conductive release film, including:

(Conductive layer formation process)
This step can be performed in the same manner as the method for manufacturing a conductive film according to the third embodiment. Therefore, the explanation will be omitted here.

(Release layer formation process)
The mold release agent composition used in this step contains a silicone compound. Since the explanation of the silicone compound is the same as that of the fourth embodiment, the explanation will be omitted here.
In addition to the silicone compound, the mold release agent composition may contain additives such as an organic solvent, a curing catalyst, a binder component other than the silicone compound, an adhesion improver, and an antistatic agent, if necessary. Good too. When addition-curing silicone is used as the silicone compound, it is preferable to mix at least one of toluene and methyl ethyl ketone as the organic solvent. Conventional methods are applied to the blending ratio and blending method of each material contained in the mold release agent composition.
The method of applying the mold release agent composition to the conductive layer and the method of drying and curing the applied coating film can be performed in the same manner as the application method and drying/curing method when forming the conductive layer.
The conductive release film according to the present invention can be manufactured by the above method.

(Production Example 1) Synthesis of polyanion Dissolve 206 g of sodium styrene sulfonate in 1000 ml of ion-exchanged water, and while stirring at 80°C, add 1.14 g of ammonium persulfate oxidizing agent solution previously dissolved in 10 ml of water for 20 minutes. was added dropwise and the solution was stirred for 12 hours.
1,000 ml of sulfuric acid diluted to 10% by mass was added to the obtained sodium polystyrene sulfonate-containing solution, and about 1,000 ml of the solvent in the obtained polystyrene sulfonic acid-containing solution was removed by ultrafiltration. Next, 2000 ml of ion-exchanged water was added to the residual liquid, about 2000 ml of the solvent was removed by ultrafiltration, and the polystyrene sulfonic acid was washed with water. This water washing operation was repeated three times.
Water in the resulting solution was removed under reduced pressure to obtain colorless solid polystyrene sulfonic acid.

(Production Example 2) Synthesis of conductive composite A solution of 14.2 g of 3,4-ethylenedioxythiophene and 36.7 g of polystyrene sulfonic acid obtained in Production Example 1 dissolved in 2000 ml of ion-exchanged water was prepared. Mixed at 20°C. While keeping the resulting mixed solution at 20°C and stirring, 29.64 g of ammonium persulfate and 8.0 g of ferric sulfate oxidation catalyst solution dissolved in 200 ml of ion-exchanged water were slowly added, and the mixture was stirred for 3 hours. The mixture was stirred and reacted.
After the reaction, 2000 ml of ion-exchanged water was added to the reaction solution, and about 2000 ml of the solvent was removed by ultrafiltration. This operation was repeated three times.
Next, 200 ml of sulfuric acid diluted to 10% by mass and 2,000 ml of ion-exchanged water were added to the obtained solution, approximately 2,000 ml of the solvent was removed by ultrafiltration, and 2,000 ml of ion-exchanged water was added to the remaining solution. About 2000 ml of solvent was removed by ultrafiltration. This operation was repeated three times.
Further, 2000 ml of ion-exchanged water was added to the obtained solution, and about 2000 ml of the solvent was removed by ultrafiltration. This operation was repeated five times to obtain an aqueous dispersion of polystyrene sulfonic acid-doped poly(3,4-ethylenedioxythiophene) (PEDOT-PSS) with a solid content concentration of 1.2% by mass.

(Example 1)
15 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2 (solid content 0.18 g) was added with 65 g of water, 10 g of propylene glycol, and a water-dispersed polyester resin, Pluscoat RZ-570 (manufactured by Gooh Kagaku Co., Ltd., solid content). 25% by mass, Tg 60° C.) and 300 g of methanol were added to obtain a paint.
The obtained paint was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) using a #4 bar coater and dried at 120°C for 1 minute to obtain a conductive film with a conductive layer on the PET film. .
Table 1 shows the results of measuring the surface resistance value of the obtained conductive film. Further, the Tg of the water-dispersible resin used in this example is shown in the column of "Tg of binder resin (° C.)" in Table 1.

Next, 1.5 g of addition-curing silicone KS-3703T (manufactured by Shin-Etsu Chemical Co., Ltd., solid content 30% by mass, toluene solution), 25.5 g of toluene, 63 g of methyl ethyl ketone, and CAT-PL, a platinum catalyst. -50T (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.03 g was mixed to obtain a paint.
The resulting paint was applied to the surface of the conductive layer of the conductive film obtained above using a #8 bar coater, and dried at 150°C for 2 minutes to form a release layer on top of the conductive layer. A conductive release film was obtained.
Table 1 shows the results of measuring the surface resistance value of the obtained conductive release film.

(Example 2)
Example 1 except that 10 g of RZ-570 in Example 1 was changed to 10 g of Pluscoat RZ-105 (manufactured by Gooh Kagaku Co., Ltd., solid content 25% by mass, Tg 52°C), which is a water-dispersed polyester resin. Similarly, a conductive film and a conductive release film were obtained, and their surface resistance values were measured.

(Example 3)
Example 1 except that 10 g of RZ-570 in Example 1 was changed to 10 g of Pluscoat Z-565 (manufactured by Gooh Kagaku Co., Ltd., solid content 25% by mass, Tg 64°C), which is a water-dispersed polyester resin. Similarly, a conductive film and a conductive release film were obtained, and their surface resistance values were measured.

(Example 4)
Example 1 except that 10 g of RZ-570 in Example 1 was changed to 10 g of Pluscoat Z-561 (manufactured by Gooh Kagaku Co., Ltd., solid content 25% by mass, Tg 64°C), which is a water-dispersed polyester resin. Similarly, a conductive film and a conductive release film were obtained, and their surface resistance values were measured.

(Example 5)
In Example 1, 10 g of RZ-570 was changed to 8.3 g of Vylonal MD-1245 (manufactured by Toyobo Co., Ltd., solid content 30% by mass, Tg 61 ° C.), which is a water-dispersed polyester resin, and the amount of water was 66.7 g. A conductive film and a conductive release film were obtained in the same manner as in Example 1, except that the film was changed to, and the surface resistance value thereof was measured.

(Example 6)
In Example 1, 10 g of RZ-570 was changed to 10 g of Pesresin A-124GP (manufactured by Takamatsu Yushi Co., Ltd., solid content 25% by mass, Tg 55 ° C.), which is a mixture of water-dispersed polyester resin and glycidyl group-containing acrylic resin. Except for this, a conductive film and a conductive release film were obtained in the same manner as in Example 1, and their surface resistance values were measured.

(Comparative example 1)
In Example 1, 10 g of RZ-570 was changed to 12.5 g of Pluscoat Z-221 (manufactured by Gooh Kagaku Co., Ltd., solid content 20% by mass, Tg 47°C), which is a water-dispersed polyester resin, and the amount of water was changed to 62.5 g. A conductive film and a conductive release film were obtained in the same manner as in Example 1, except that the amount was changed to .5 g, and the surface resistance value thereof was measured.

(Comparative example 2)
Example 1 except that 10 g of RZ-570 in Example 1 was changed to 10 g of Pluscoat Z-446 (manufactured by Gooh Kagaku Co., Ltd., solid content 25% by mass, Tg 47°C), which is a water-dispersed polyester resin. Similarly, a conductive film and a conductive release film were obtained, and their surface resistance values were measured.

(Comparative example 3)
In Example 1, 10 g of RZ-570 was changed to 8.3 g of Vylonal MD-1100 (manufactured by Toyobo Co., Ltd., solid content 30% by mass, Tg 40 ° C.), which is a water-dispersed polyester resin, and the amount of water was 66.7 g. A conductive film and a conductive release film were obtained in the same manner as in Example 1, except that the film was changed to, and the surface resistance value thereof was measured.

(Comparative example 4)
In Example 1, 10 g of RZ-570 was changed to 7.35 g of Vylonal MD-1200 (manufactured by Toyobo Co., Ltd., solid content 34% by mass, Tg 67 ° C.), which is a water-dispersed polyester resin, and the amount of water was 67.65 g. A conductive film and a conductive release film were obtained in the same manner as in Example 1, except that the film was changed to, and the surface resistance value thereof was measured.

(Comparative example 5)
Same as Example 1 except that 10 g of RZ-570 in Example 1 was changed to 10 g of Vylonal MD-1480 (manufactured by Toyobo Co., Ltd., solid content 25% by mass, Tg 20 ° C.), which is a water-dispersed polyester resin. A conductive film and a conductive release film were obtained, and their surface resistance values were measured.

<Evaluation>
[Surface resistance value]
Regarding the conductive film of each example, the surface resistance value of the conductive layer was measured using a resistivity meter (manufactured by Mitsubishi Chemical Analytic Corporation, Hiresta) under the condition of an applied voltage of 10 V. Table 1 shows the measurement results of surface resistance values.
For the conductive release film of each example, a probe was placed on the release layer, and the surface resistance value of the conductive layer was measured with a resistivity meter (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) with the release layer interposed. The measurement was carried out under the condition of an applied voltage of 10 V using a HIRESTA). Table 1 shows the measurement results of surface resistance values. In addition, "Ω/□" in the table means ohm per square. Moreover, "1.0E+08" represents "1.0×10 ⁸ ".

[Peeling force]
Regarding the conductive release film of each example, the peel force was measured by the method described below to evaluate the release properties of the release layer. The measurement results are shown in Table 1.
A 25 mm wide polyester adhesive tape (manufactured by Nitto Denko Corporation, No. 31B) was pasted on the surface of the release layer of the conductive release film, and a load of 1976 Pa was applied from above the adhesive tape and pressure was applied at 25°C for 20 hours. Processed. Next, in accordance with JIS Z0237, the adhesive tape attached to the release layer was peeled off at an angle of 180° (peel speed 0.3 m/min) using a tensile tester to determine the peel force (unit: N). It was measured. The measurement results are shown in Table 1. It means that the smaller the peeling force is, the higher the mold release property of the mold release layer is.

[Adhesion]
Regarding the conductive release film of each example, the surface of the release layer was rubbed 10 times with a finger, and the degree of damage to the release layer was evaluated using the following criteria. The results are shown in Table 1.
(Evaluation 1): The release layer completely falls off by the fifth finger rubbing, and easy peelability is lost. In other words, the adhesion between the release layer and the conductive layer is poor.
(Evaluation 2): The release layer remains until the 5th finger rub, but after that, the release layer completely falls off by the 10th finger rub, and easy peelability is lost. In other words, the adhesion between the release layer and the conductive layer is poor.
(Evaluation 3): The release layer did not fall off by finger rubbing 10 times, a large change in the color of the release layer was observed, and the easy peelability decreased. In other words, the adhesion between the release layer and the conductive layer is normal.
(Evaluation 4): The release layer did not fall off by finger rubbing 10 times, and a small change in the color of the release layer was observed, but the easy peelability hardly decreased. In other words, the adhesion between the release layer and the conductive layer is excellent.
(Evaluation 5): The release layer did not fall off by finger rubbing 10 times, no change was observed in the color of the release layer, and easy peelability did not decrease. In other words, the adhesion between the release layer and the conductive layer is particularly excellent.
In the above five-level evaluation criteria, easy peelability (mold releasability) is based on the results of testing the ease of peeling off an adhesive tape after it has been applied to a finger-rubbed surface. The change in color of the release layer indicates the degree of peeling at the interface between the release layer and the conductive layer. If this interface is partially peeled off, the interface will be lifted up when the adhesive tape attached to the surface of the release layer is peeled off, and the peelability will be reduced.

From the results in Table 1, it can be seen that in the conductive films of Examples 1 to 6 according to the present invention, the adhesion of the conductive layer to the PET film and the release layer was generally good. Good adhesion is achieved when the conductive layer contains a water-dispersible resin having a Tg within a specific range. The conductive layers of Comparative Examples 1 to 5 containing water-dispersible resins with too high or too low Tg had poor adhesion and were not suitable for practical use. Note that Examples 2 and 6 are comparative examples.

Claims (11)

a conductive layer consisting of a film base material and a cured layer of a conductive polymer dispersion formed on at least one surface of the film base material;
A conductive release film comprising: a release layer containing an addition-curing silicone resin laminated on the surface of the conductive layer;
The conductive polymer dispersion liquid contains a conductive composite containing a π-conjugated conductive polymer and a polyanion, a water-dispersible polyester resin having a glass transition point of 60° C. or higher and 64° C. or lower, and a dispersion medium. death,
A conductive release film, wherein the content of the water-dispersible polyester resin is 1000 parts by mass or more and 2000 parts by mass or less with respect to 100 parts by mass of the conductive composite in the conductive polymer dispersion. The conductive release film according to claim 1, wherein the conductive polymer dispersion further contains a glycidyl group-containing acrylic resin. The conductive release film according to claim 1 or 2, wherein the dispersion medium contains a monohydric alcohol. The conductive release film according to claim 3, wherein the monohydric alcohol contains methanol. The conductive release film according to any one of claims 1 to 4, wherein the conductive polymer dispersion further contains a highly conductive agent. The conductive release film according to claim 5, wherein the highly conductive agent contains a dihydric alcohol. The conductive release film according to claim 5 or 6, wherein the highly conductive agent contains propylene glycol. The conductive release film according to any one of claims 1 to 7, wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene). The conductive release film according to any one of claims 1 to 8, wherein the polyanion is polystyrene sulfonic acid. The conductive release film according to any one of claims 1 to 9, wherein the film base material is formed of a polyester resin. A method for producing a conductive release film according to any one of claims 1 to 10, comprising:
Applying a conductive polymer dispersion to at least one surface of the film base material and drying the formed coating film to form a conductive layer;
Applying a mold release agent composition containing an addition-curable silicone resin to the surface of the conductive layer and drying the formed coating film to form a mold release layer,
The conductive polymer dispersion liquid contains a conductive composite containing a π-conjugated conductive polymer and a polyanion, a water-dispersible polyester resin having a glass transition point of 60° C. or higher and 64° C. or lower, and a dispersion medium. death,
A method for producing a conductive release film, wherein the content of the water-dispersible polyester resin is 1000 parts by mass or more and 2000 parts by mass or less based on 100 parts by mass of the conductive composite in the conductive polymer dispersion.