Conductive polymer dispersion, conductive laminate, and method for producing the same

Abstract

The present invention provides a conductive laminate having a conductive release layer that combines conductivity and release properties, a method for manufacturing the same, and a conductive polymer dispersion suitable for the manufacturing method. [Solution] A conductive polymer dispersion containing a conductive composite comprising a π-conjugated conductive polymer and a polyanion, a silicone emulsion, a water-dispersible polyester resin, and an aqueous dispersion medium. Preferably, the dispersion further contains at least one of a water-soluble organic solvent, a platinum-based catalyst, and a basic compound.

Description

Technical Field

[0001] The present invention relates to a conductive polymer dispersion, a conductive laminate, and a method for producing the same.

Background Art

[0002] As a technology related to the production of electronic devices, a conductive layer may be formed on the surface of a resin substrate. Since π-conjugated conductive polymers are excellent in conductivity and transparency, they have attracted attention as materials for forming conductive layers. Further, a release layer containing silicone may be laminated on the surface of the conductive layer and used. Such a conductive release film is disclosed in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the conductive polymer dispersion of Patent Document 1 contains a polyolefin-based resin, its adhesion to a polyolefin-based substrate is particularly excellent. Since polyolefin has excellent processability, it has the advantage of being applicable to various uses. If a release layer containing silicone is further laminated on the surface of the conductive layer, peelability (release property) can be imparted to the surface. However, there is a problem that the number of steps for laminating the release layer on the surface of the conductive layer increases.

[0005] The present invention provides a conductive laminate having a conductive release layer having both conductivity and release property, a method for producing the same, and a conductive polymer dispersion suitable for the production method.

Means for Solving the Problems

[0006] [1] A conductive polymer dispersion comprising a conductive composite containing a π-conjugated conductive polymer and a polyanion, a silicone emulsion, a water-dispersible polyester resin, and an aqueous dispersion medium. [2] The conductive polymer dispersion according to [1], wherein the water content in the aqueous dispersion medium is 40 parts by mass or more per 1 part by mass of the conductive composite. [3] The conductive polymer dispersion according to [1] or [2], wherein the aqueous dispersion medium contains a water-soluble organic solvent, and the content of the water-soluble organic solvent relative to the total mass of the aqueous dispersion medium is 50% by mass or more and 95% by mass or less. [4] A conductive polymer dispersion according to any one of [1] to [3], further comprising a platinum-based catalyst. [5] A conductive polymer dispersion according to any one of [1] to [4], further comprising a basic compound. [6] The conductive polymer dispersion according to any one of [1] to [5], wherein the content of the basic compound relative to the total mass of the conductive polymer dispersion is 1 mM or more and 10 mM or less. [7] The conductive polymer dispersion according to any one of [1] to [6], wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene) or the polyanion is polystyrene sulfonic acid. [8] A conductive laminate comprising a substrate and a conductive release layer formed on at least a portion of the surface of the substrate, wherein the conductive release layer is a cured product of a conductive polymer dispersion according to claim 1 or 2. [9] The conductive laminate according to [8], wherein the substrate is a polyethylene terephthalate film.

[10] A method for producing a conductive laminate, comprising coating at least a portion of a substrate surface with a conductive polymer dispersion according to any one of [1] to [7] to form a conductive layer. [Effects of the Invention]

[0007] In the conductive laminate of the present invention, the conductive release layer exhibits excellent conductivity and release properties. Furthermore, the conductive release layer has excellent adhesion to the substrate. The manufacturing method of the present invention allows for the easy production of the above-mentioned excellent conductive laminate. The conductive polymer dispersion of the present invention is suitable for the above-mentioned manufacturing method and exhibits excellent wettability to the substrate.

[0008] This invention is believed to contribute to SDG Goal 12, "Responsible Consumption and Production."

[0009] In this specification and the claims, the lower and upper limits of the numerical ranges indicated by "~" are to be included within those numerical ranges. [Modes for carrying out the invention]

[0010] <<Conductive polymer dispersion>> A first aspect of the present invention is a conductive polymer dispersion containing a conductive composite comprising a π-conjugated conductive polymer and a polyanion, a silicone emulsion, a water-dispersible polyester resin, and an aqueous dispersion medium.

[0011] [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 dops the π-conjugated conductive polymer to form a conductive composite. In polyanions, only some anionic groups are doped into the π-conjugated conductive polymer, leaving excess anionic groups that do not participate in doping. Since these excess anionic groups are hydrophilic, the conductive composite is water-dispersible.

[0012] (π-conjugated conductive polymers) Any organic polymer whose main chain is composed of a π-conjugated system can be used as the π-conjugated conductive polymer. Examples include polypyrrole-based conductive polymers, polythiophene-based conductive polymers, polyacetylene-based conductive polymers, polyphenylene-based conductive polymers, polyphenylene-vinylene-based conductive polymers, polyaniline-based conductive polymers, polyacene-based conductive polymers, polythiophene-vinylene-based conductive polymers, and copolymers thereof. From the viewpoint of stability in air, polypyrrole-based conductive polymers, polythiophenes, and polyaniline-based conductive polymers are preferred, and from the viewpoint of transparency, polythiophene-based conductive polymers are more preferred.

[0013] Examples of polythiophene-based conductive polymers include polythiophene, poly(3-methylthiophene), poly(3-ethylthiophene), poly(3-propylthiophene), poly(3-butylthiophene), poly(3-hexylthiophene), poly(3-heptylthiophene), poly(3-octylthiophene), poly(3-decylthiophene), poly(3-dodecylthiophene), poly(3-octadecylthiophene), poly(3-bromothiophene), poly(3-chlorothiophene), and poly(3-iodine). 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-Dodecyl Poly(3-octadecyloxythiophene), poly(3,4-dihydroxythiophene), poly(3,4-dimethoxythiophene), poly(3,4-diethoxythiophene), poly(3,4-dipropoxythiophene), poly(3,4-dibutoxythiophene), poly(3,4-dihexyloxythiophene), poly(3,4-diheptyloxythiophene), poly(3,4-dioctyloxythiophene), poly(3,4-didecyloxythiophene), poly(3,4-di Examples include dodecyloxythiophene, poly(3,4-ethylenedioxythiophene), poly(3,4-propylenedioxythiophene), poly(3,4-butylenedioxythiophene), poly(3-methyl-4-methoxythiophene), poly(3-methyl-4-ethoxythiophene), poly(3-carboxythiophene), poly(3-methyl-4-carboxythiophene), poly(3-methyl-4-carboxyethylthiophene), and poly(3-methyl-4-carboxybutylthiophene). Examples of polypyrrole-based conductive polymers include polypyrrole, poly(N-methylpyrrole), poly(3-methylpyrrole), poly(3-ethylpyrrole), poly(3-n-propylpyrrole), poly(3-butylpyrrole), poly(3-octylpyrrole), poly(3-decylpyrrole), poly(3-dodecylpyrrole), poly(3,4-dimethylpyrrole), poly(3,4-dibutylpyrrole), poly(3-carboxypyrrole), poly(3-methyl-4-carboxypyrrole), poly(3-methyl-4-carboxyethylpyrrole), poly(3-methyl-4-carboxybutylpyrrole), poly(3-hydroxypyrrole), poly(3-methoxypyrrole), poly(3-ethoxypyrrole), poly(3-butoxypyrrole), poly(3-hexyloxypyrrole), and poly(3-methyl-4-hexyloxypyrrole). Examples of polyaniline-based conductive polymers include polyaniline, poly(2-methylaniline), poly(3-isobutylaniline), poly(2-anilinesulfonic acid), and poly(3-anilinesulfonic acid). Among these π-conjugated conductive polymers, poly(3,4-ethylenedioxythiophene) is particularly preferred due to its excellent conductivity, transparency, and heat resistance. The conductive composite may contain one type of π-conjugated conductive polymer, or two or more types.

[0014] (Polyanion) A polyanion is a polymer that has two or more monomer units containing anionic groups within its molecule. The anionic groups of this polyanion function as dopants for π-conjugated conductive polymers, thereby improving the conductivity of the π-conjugated conductive polymer. The anionic group of the polyanion is preferably a sulfo group or a carboxyl group. Specific examples of such polyanions include polystyrene sulfonic acid, polyvinyl sulfonic acid, polyallyl sulfonic acid, polyacrylate esters having a sulfo group, polymethacrylate esters having a sulfo group (e.g., poly(4-sulfobutyl methacrylate), polysulfoethyl methacrylate, polymethacryloyloxybenzene sulfonic acid), polymers having a sulfo group such as poly(2-acrylamido-2-methylpropanesulfonic acid), polyisoprene sulfonic acid, and polymers having a carboxy group such as polyvinyl carboxylic acid, polystyrene carboxylic acid, polyallyl carboxylic acid, polyacrylic acid, polymethacrylic acid, poly(2-acrylamido-2-methylpropane carboxylic acid), polyisoprene carboxylic acid. The polyanion may be a homopolymer obtained by polymerizing a single monomer or a copolymer obtained by polymerizing two or more monomers. Among these polyanions, polymers having a sulfo group are preferred and polystyrene sulfonic acid is more preferred because the conductivity can be made higher. The polyanion 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, and more preferably 100,000 or more and 500,000 or less. The mass average molecular weight is the average molecular weight on a mass basis measured by gel filtration chromatography and determined in terms of pullulan.

[0015] 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, more preferably 10 parts by mass or more and 700 parts by mass or less, and even more preferably 100 parts by mass or more and 500 parts by mass or less with respect to 100 parts by mass of the π-conjugated conductive polymer. If the content ratio of the polyanion is at least the lower limit value, the doping effect on the π-conjugated conductive polymer tends to be stronger and the conductivity becomes higher. On the other hand, if the content of the polyanion is at most the upper limit value, the π-conjugated conductive polymer can be sufficiently contained, so that sufficient conductivity can be ensured.

[0016] As the content of the conductive composite contained in the conductive polymer dispersion of this embodiment, it is preferably 0.01% by mass or more and 5.0% by mass or less, more preferably 0.10% by mass or more and 2% by mass or less, and still more preferably 0.15% by mass or more and 1.0% by mass or less with respect to the total mass of the conductive polymer dispersion. When it is at least the lower limit value of the above range, the conductivity of the conductive release layer formed by applying the conductive polymer dispersion can be further improved. When it is at most the upper limit value of the above range, the dispersibility of the conductive composite in the conductive polymer dispersion can be enhanced, and a uniform conductive release layer can be formed.

[0017] [Silicone Emulsion] A silicone emulsion is one in which a silicone-based compound is dispersed in an aqueous dispersion medium to form an emulsion. A surfactant (emulsifier) may be included together to form an emulsion of the silicone-based compound. As the silicone-based compound, the silicone-based compounds contained in known release agents can be applied. Here, silicone is a polymer collectively referred to as organopolysiloxane having a main chain (silicone skeleton) to 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 those having a reactive functional group or a non-reactive functional group in a part of polydimethylsiloxane are also preferable. Also, acrylic resins, alkyd resins, etc. having organopolysiloxane in the side chain can be applied as the silicone-based compound.

[0018] As the silicone-based compound, curable silicone is preferable because it exhibits stable release properties and excellent film-forming properties. The curable silicone may be either an addition-curable silicone or a condensation-curable silicone. The curable silicone forms a three-dimensional crosslinked structure and cures when reacted. Examples of addition-curing silicones include linear polymers having siloxane bonds, specifically polydimethylsiloxane having vinyl groups at both ends of the linear chain, and hydrogensilane. A platinum-based curing catalyst may be used to accelerate curing. Specific examples of addition-curing silicones include KM-3951, X-52-6068, X-52-151, and X-52-6069 (all manufactured by Shin-Etsu Chemical Co., Ltd.).

[0019] The content of the solids (non-volatile components) of the silicone emulsion relative to the total mass of the conductive polymer dispersion in this embodiment is preferably 0.1% by mass or more and 4.0% by mass or less, more preferably 0.5% by mass or more and 3.5% by mass or less, even more preferably 1.0% by mass or more and 3.0% by mass or less, and most preferably 1.5% by mass or more and 2.5% by mass or less. If the value is above the lower limit of the above range, excellent release properties can be imparted to the conductive release layer. If the value is below the upper limit of the above range, the conductivity of the conductive release layer can be sufficiently maintained, and excellent adhesion of the conductive release layer to the substrate can be maintained.

[0020] [Hardening agent] The conductive polymer dispersion in this embodiment may contain a curing agent that accelerates the curing of the curable silicone. The curing agent is selected according to the type of curable silicone used. In the case of addition-type silicones, it is preferable to use a platinum-based catalyst as a curing agent. Specific examples of platinum-based catalysts include CAT-PL-50T and CAT-PM-10A (manufactured by Shin-Etsu Chemical Co., Ltd.). In the case of condensation reaction type silicone resins, it is preferable to use an organotin catalyst (e.g., an organotin acylate catalyst) as a curing agent. Specific examples of organotin catalysts include CAT-PS-8S (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0021] [Water-dispersible polyester resin] A water-dispersible polyester resin is a polyester resin that is made dispersible in water. In the conductive polymer dispersion of this embodiment, the water-dispersible polyester resin may be emulsified by also including an emulsifier. By including a water-dispersible polyester resin in the conductive polymer dispersion of this embodiment, the adhesion of the formed conductive release layer to the substrate can be improved, and the film strength of the conductive release layer can be increased.

[0022] The water-dispersible polyester resin is preferably dispersible in 100g of distilled water at 25°C in an amount of 1g or more, preferably 5g or more, and more preferably 10g or more, and it is even more preferable that it can be emulsified within these preferred ranges.

[0023] Water-dispersible polyester resins preferably have hydrophilic functional groups such as hydroxyl groups, carboxyl groups, and sulfo groups. The presence of hydrophilic functional groups improves dispersibility in water. The hydrophilic functional groups of the water-dispersible polyester resin may form salts with cations such as sodium ions and potassium ions.

[0024] The number-average molecular weight of the water-dispersible polyester resin is preferably between 1,000 and 30,000. The number-average molecular weight of the water-dispersible polyester resin is the number-reference molecular weight determined by measuring the elution time using gel permeation chromatography (GPC) and based on a calibration curve of elution time versus molecular weight obtained in advance from a polystyrene standard substance with a known molecular weight. If the number-average molecular weight of the water-dispersible polyester resin is above the lower limit, the adhesion of the conductive release layer will be higher, and if it is below the upper limit, the water-dispersibility of the water-dispersible polyester resin will be higher.

[0025] The content of the water-dispersible polyester resin in the conductive polymer dispersion is preferably 100 parts by mass or more and 50,000 parts by mass or less, more preferably 100 parts by mass or more and 10,000 parts by mass or less, and even more preferably 200 parts by mass or more and 2,000 parts by mass or less, per 100 parts by mass of the conductive composite. If the value is above the lower limit, the adhesion and film strength of the conductive release layer to the substrate will be further improved, and if it is below the upper limit, a decrease in conductivity due to a lower content of conductive composite can be prevented.

[0026] Furthermore, the content of the water-dispersible polyester resin in the conductive polymer dispersion is preferably 10 parts by mass or more and 1000 parts by mass or less, more preferably 30 parts by mass or more and 500 parts by mass or less, and even more preferably 50 parts by mass or more and 100 parts by mass or less, per 100 parts by mass of the solid content of the silicone emulsion. Within the above range, the adhesion and film strength of the conductive release layer can be improved without impairing the release properties of the silicone emulsion.

[0027] [Aqueous dispersion medium] The aqueous dispersion medium contained in the conductive polymer dispersion in this embodiment is water, or a mixture of water and an organic solvent.

[0028] Examples of organic solvents include alcohol-based solvents, ether-based solvents, ketone-based solvents, ester-based solvents, and aromatic hydrocarbon-based solvents. Examples of alcohol-based solvents include monohydric alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 2-methyl-2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, allyl alcohol, propylene glycol monomethyl ether, and ethylene glycol monomethyl ether; and dihydric alcohols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butanediol. Examples of ether-based solvents include diethyl ether, dimethyl ether, and propylene glycol dialkyl ether. Examples of ketone-based solvents include diethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, methyl amyl ketone, diisopropyl ketone, methyl ethyl ketone, acetone, and diacetone alcohol. Examples of ester-based solvents include ethyl acetate, propyl acetate, and butyl acetate. Examples of aromatic hydrocarbon solvents include benzene, toluene, xylene, ethylbenzene, propylbenzene, and isopropylbenzene. Examples of solvents not classified as above include dimethyl sulfoxide. Organic solvents may be used individually or in combination of two or more types.

[0029] In this embodiment, a mixed solvent of water and a water-soluble organic solvent is preferred for the aqueous dispersion, from the viewpoint of improving the dispersibility of the silicone emulsion and the water-dispersible polyester resin. Here, a water-soluble organic solvent is defined as an organic solvent whose solubility in 100g of water at 20°C is 1g or more, and a non-water-soluble organic solvent is defined as an organic solvent whose solubility in 100g of water at 20°C is less than 1g. As the water-soluble organic solvent, one or more selected from alcohol-based solvents are preferred.

[0030] Since conductive composites have high dispersibility in water, from the viewpoint of improving the dispersibility of conductive composites, the water content relative to the total mass of the aqueous dispersion medium is preferably, for example, 10% to 50% by mass, more preferably 15% to 40% by mass, and even more preferably 20% to 30% by mass. Furthermore, the water content per 1 part by mass of the conductive composite is preferably 40 parts by mass or more, more preferably 50 parts by mass or more and 1000 parts by mass or less, even more preferably 80 parts by mass or more and 800 parts by mass or less, and particularly preferably 100 parts by mass or more and 400 parts by mass or less. As a dispersion medium other than water, the aforementioned water-soluble organic solvents are preferred.

[0031] The content ratio of the water-soluble organic solvent to the total mass of the aqueous dispersion medium in the conductive polymer dispersion of this embodiment is preferably, for example, 50% by mass or more and 95% by mass or less, more preferably 60% by mass or more and 90% by mass or less, and even more preferably 70% by mass or more and 85% by mass or less.

[0032] [Basic compounds] The conductive polymer dispersion of this embodiment may contain one or more basic compounds. By including basic compounds, the wettability of the conductive polymer dispersion with respect to the substrate can be improved. Examples of basic compounds include inorganic alkalis, amine compounds, nitrogen-containing aromatic cyclic compounds, and the like.

[0033] Examples of inorganic alkalis include sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, sodium bicarbonate, potassium bicarbonate, and ammonium bicarbonate.

[0034] The content of the basic compound in the conductive polymer dispersion of this embodiment is preferably, for example, 0.1 mM or more and 50 mM or less, more preferably 0.5 mM or more and 20 mM or less, and even more preferably 1 mM or more and 10 mM or less. Within the above range, the wettability of the conductive polymer dispersion to the substrate can be further improved.

[0035] [Other additives] The conductive polymer dispersion may contain other additives. The additives are not particularly limited as long as the effects of the present invention are obtained, and for example, surfactants, inorganic conductive agents, defoaming agents, coupling agents, antioxidants, ultraviolet absorbers, etc., can be used. Examples of surfactants include nonionic, anionic, and cationic surfactants, but nonionic surfactants are preferred in terms of storage stability. Polymer-based surfactants such as polyvinylpyrrolidone may also be added. Examples of inorganic conductive agents include metal ions and conductive carbon. Metal ions can be generated by dissolving metal salts in water. Examples of coupling agents include silane coupling agents having epoxy groups, vinyl groups, or amino groups. Examples of antioxidants include phenolic antioxidants, amine antioxidants, phosphorus antioxidants, sulfur antioxidants, and sugars. Examples of UV absorbers include benzotriazole-based UV absorbers, benzophenone-based UV absorbers, salicylate-based UV absorbers, cyanoacrylate-based UV absorbers, oxanilide-based UV absorbers, hindered amine-based UV absorbers, and benzoate-based UV absorbers.

[0036] When the conductive polymer dispersion contains the additive, the proportion of the additive can be appropriately determined depending on the type of additive, but for example, it can be in the range of 0.001 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the conductive composite.

[0037] <Method for producing conductive polymer dispersion> A method for producing the conductive polymer dispersion according to this embodiment includes, for example, adding a silicone emulsion, a water-dispersible polyester resin, and, if necessary, a basic compound to an aqueous dispersion of a conductive composite. The aqueous dispersion of the conductive composite may be obtained by chemical oxidation polymerization of monomers that form a π-conjugated conductive polymer in an aqueous solution of polyanions using a known method, or a commercially available one may be used.

[0038] <<Conductive Laminate>> A second aspect of the present invention is a conductive laminate comprising a substrate and a conductive release layer formed on at least a portion of the surface of the substrate, wherein the conductive release layer is made of a cured product of the conductive polymer dispersion of the first aspect.

[0039] [Conductive release layer] The area in which the conductive release layer is formed may be the entire surface of any surface of the substrate, or it may be only a part of it. In the case of a conductive film, it is preferable that a conductive release layer of substantially uniform thickness is formed on substantially the entire surface of one or the other surface of the film substrate. If the conductive release layer is formed on only a part of the surface of the substrate, for example, the conductive release layer may be a fine conductive pattern such as a circuit or an electrode, or the area with the conductive release layer and the area without the conductive release layer may exist on the same surface and be roughly separated.

[0040] The average thickness of the conductive release layer is preferably 10 nm to 100 μm, more preferably 20 nm to 50 μm, and even more preferably 30 nm to 30 μm. If the average thickness of the conductive release layer is above the lower limit, high conductivity can be achieved, and if it is below the upper limit, the adhesion of the conductive release layer to the substrate is further improved.

[0041] [Base material] The substrate may be made of an insulating material or a conductive material. The shape of the substrate is not particularly limited, and examples include mainly flat shapes such as films and substrates. Examples of insulating materials include glass, synthetic resins, and ceramics. Examples of conductive materials include metals, conductive metal oxides, and carbon.

[0042] (Film substrate) When a film substrate is used as the aforementioned substrate, the conductive laminate becomes a conductive film. Examples of the film substrate include plastic films made of synthetic resins. Examples of the synthetic resins include ethylene-methyl methacrylate copolymer resin, ethylene-vinyl acetate copolymer resin, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinyl alcohol, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyacrylate, polycarbonate, polyvinylidene fluoride, polyarylate, styrene elastomer, polyester elastomer, polyethersulfone, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyimide, cellulose triacetate, and cellulose acetate propionate. From the viewpoint of improving adhesion between the film substrate and the conductive release layer, the synthetic resin for the film substrate is preferably a polyester resin, and among these, polyethylene terephthalate is preferred.

[0043] The synthetic resin used for the film substrate may be amorphous or crystalline. The film substrate may be unstretched or stretched. The film substrate may be subjected to surface treatments such as corona discharge treatment, plasma treatment, or flame treatment in order to further improve the adhesion of the conductive release layer.

[0044] The average thickness of the film substrate is preferably 5 μm to 500 μm, and more preferably 20 μm to 200 μm. If the average thickness of the film substrate is above the lower limit, it becomes less prone to tearing, and if it is below the upper limit, sufficient flexibility as a film can be ensured. The average thickness of the film substrate is calculated by measuring the thickness at 10 randomly selected locations and averaging those measurements.

[0045] (Glass substrate) Examples of glass substrates include alkali-free glass substrates, soda-lime glass substrates, borosilicate glass substrates, and quartz glass substrates. Since the presence of alkaline components in the substrate tends to reduce the conductivity of the conductive release layer, alkali-free glass is preferred among the glass substrates. Here, alkali-free glass refers to a glass composition in which the content of alkaline components is 0.1% by mass or less of the total mass of the glass composition.

[0046] The average thickness of the glass substrate is preferably 100 μm or more and 3000 μm or less, and more preferably 100 μm or more and 1000 μm or less. If the average thickness of the glass substrate is above the lower limit, it becomes less prone to breakage, and if it is below the upper limit, it contributes to thinning the conductive laminate. The average thickness of the glass substrate is the average of the measurements taken at 10 randomly selected locations.

[0047] ≪Method for manufacturing conductive laminates≫ A third aspect of the present invention is a method for manufacturing a conductive laminate, comprising coating at least a portion of the surface of a substrate with the conductive polymer dispersion of the first aspect to form a conductive release layer. The manufacturing method of this aspect can be used to manufacture the conductive laminate of the second aspect.

[0048] Methods for coating (applying) a conductive polymer dispersion to any surface of a substrate include, for example, methods using coaters such as gravure coaters, roll coaters, curtain flow coaters, spin coaters, bar coaters, reverse coaters, kiss coaters, fountain coaters, rod coaters, air doctor coaters, knife coaters, blade coaters, cast coaters, and screen coaters; methods using sprayers such as air sprayers, airless sprayers, and rotor dampening devices; and immersion methods such as dipping.

[0049] There are no particular restrictions on the amount of conductive polymer dispersion applied to the substrate, but considering uniform and even coating, as well as conductivity and film strength, the solid content should be approximately 0.01 g / m². 2 More than 10.0g / m 2 The following range is preferable.

[0050] It is preferable to dry the coating film, which consists of a conductive polymer dispersion applied to the substrate, to remove the dispersion medium. Methods for drying the coating film include heat drying and vacuum drying. For heat drying, for example, methods such as hot air heating and infrared heating can be used. When applying heat drying, the heating temperature is set appropriately according to the dispersion medium used, but is usually within the range of 50°C to 200°C. Here, the heating temperature is the set temperature of the drying apparatus. Within the above heating temperature range, a suitable drying time is preferably 0.5 minutes to 30 minutes, and more preferably 1 minute to 15 minutes. By the above method, a conductive laminate can be obtained in which a conductive release layer (conductive film) formed by the curing of the coating film is formed. [Examples]

[0051] (Manufacturing Example 1) Production of polystyrene sulfonic acid 206 g of sodium styrene sulfonate was dissolved in 1000 ml of deionized water, and while stirring at 80°C, 1.14 g of ammonium persulfate oxidizing agent solution, which had been previously dissolved in 10 ml of water, was added dropwise for 20 minutes, and this solution was stirred for 12 hours. To the obtained sodium polystyrene sulfonate-containing solution, 1000 ml of sulfuric acid diluted to 10% by mass was added to obtain a polystyrene sulfonic acid-containing solution. Next, approximately 1000 ml of the solvent was removed from the polystyrene sulfonic acid-containing solution by ultrafiltration, and 2000 ml of deionized water was added to the remaining solution. Approximately 2000 ml of the solvent was removed by ultrafiltration to wash the polystyrene sulfonic acid with water. This washing procedure was repeated three times. The water in the resulting solution was removed under reduced pressure to obtain colorless, solid polystyrene sulfonic acid.

[0052] (Manufacturing Example 2) Preparation of PEDOT-PSS aqueous dispersion A solution of 0.5 g of 3,4-ethylenedioxythiophene and 1.5 g of polystyrene sulfonic acid was dissolved in 15.0 g of deionized water and mixed at 20°C. Next, 89.5 g of deionized water was added. The resulting mixed solution was kept at 20°C, and while stirring, a solution of 0.03 g of ferric sulfate dissolved in 4.97 g of deionized water and a solution of 1.1 g of ammonium persulfate dissolved in 8.9 g of deionized water were slowly added, and the resulting reaction mixture was stirred for 24 hours to allow the reaction to proceed. The above reaction yielded a PEDOT-PSS aqueous dispersion containing a conductive composite (PEDOT-PSS) comprising poly(3,4-ethylenedioxythiophene) and polystyrene sulfonic acid, which are π-conjugated conductive polymers, and water as a dispersion medium. 13.2 g of Duolite C255LFH (manufactured by Sumika Chemtex, cation exchange resin) and 13.2 g of Duolite A368S (manufactured by Sumika Chemtex, anion exchange resin) were added to this dispersion, and the mixture was filtered to remove the ion exchange resins, thereby obtaining a PEDOT-PSS aqueous dispersion (solid content 1.3% by mass) from which the oxidizing agent and catalyst had been removed.

[0053] (Example 1) A conductive polymer dispersion was prepared by mixing 100g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2 with 40g of KM-3951 (manufactured by Shin-Etsu Chemical Co., Ltd., addition-curing silicone emulsion, 30% solids content, aqueous dispersion), 40g of Pluscoat RZ105 (manufactured by Go-O Chemical Co., Ltd., polyester emulsion, 25% solids content, aqueous dispersion), 4g of CAT-PM-10A (manufactured by Shin-Etsu Chemical Co., Ltd., platinum catalyst, aqueous dispersion) and 540g of methanol. Next, the film was coated onto polyethylene terephthalate (PET) film using a #8 bar coater and dried at 120°C for 1 minute to obtain a conductive film with a conductive release layer. Table 1 shows the results of measuring the surface resistance, peel strength, adhesion, and wettability (visual repulsion) of the coated conductive polymer dispersion on the PET film of the obtained conductive film.

[0054] (Example 2) A conductive film was prepared and measured in the same manner as in Example 1, except that the amount of KM-3951 was increased to 80g and CAT-PM-10A to 8g. The results are shown in Table 1.

[0055] (Example 3) A conductive film was prepared and measured in the same manner as in Example 1, except that the amount of KM-3951 was reduced to 20g and the amount of CAT-PM-10A was reduced to 2g. The results are shown in Table 1.

[0056] (Example 4) A conductive film was prepared and measured in the same manner as in Example 1, except that the amount of Pluscoat RZ105 was increased to 80g. The results are shown in Table 1.

[0057] (Example 5) A conductive film was prepared and measured in the same manner as in Example 1, except that the amount of Pluscoat RZ105 was reduced to 20g. The results are shown in Table 1.

[0058] (Example 6) A conductive film was prepared and measured in the same manner as in Example 1, except that KM-3951 was replaced with X-52-6068 (manufactured by Shin-Etsu Chemical Co., Ltd., addition-curing silicone emulsion, 30% solids content, aqueous dispersion). The results are shown in Table 1.

[0059] (Example 7) A conductive film was prepared and measured in the same manner as in Example 1, except that Pluscoat RZ105 was replaced with Pluscoat RZ570 (manufactured by Go-O Chemical Co., Ltd., polyester emulsion, solids content 25%, aqueous dispersion). The results are shown in Table 1.

[0060] (Example 8) A conductive film was prepared and measured in the same manner as in Example 1, except that 0.3 g of sodium bicarbonate was added to the conductive polymer dispersion. The results are shown in Table 1.

[0061] (Comparative Example 1) A coating was prepared in the same manner as in Example 1, except that the PEDOT-PSS aqueous dispersion was not added. A film coated with this coating was then prepared and measured. The results are shown in Table 1.

[0062] (Comparative Example 2) A conductive film was prepared and measured in the same manner as in Example 1, except that KM-3951 and CAT-PM-10A were not added. The results are shown in Table 1.

[0063] (Comparative Example 3) A conductive film was prepared and measured in the same manner as in Example 1, except that the Pluscoat RZ105 was not added. The results are shown in Table 1.

[0064] <Rating> [Surface resistance value] For each example of conductive film, the surface resistance of the conductive release layer was measured using a resistivity meter (Hyresta, manufactured by Nitto Seiko Analytech Co., Ltd.) under the condition of an applied voltage of 10V. The measurement results of the surface resistance are shown in Table 1. In the table, "Ω / □" means ohms per square. "2.0E+08" means "2.0 × 10 8 This represents "[...]" and the others are similar.

[0065] [Peeling force] For each example of conductive film, the peeling force was measured using the method described below, and the release properties of the conductive release layer were evaluated. A 25mm wide polyester adhesive tape (manufactured by Nitto Denko, No. 31B) was attached to the surface of the conductive release layer of a conductive film, and a load of 1976 Pa was applied to the adhesive tape, followed by a pressurized treatment at 25°C for 20 hours. Next, in accordance with JIS Z0237, the adhesive tape attached to the conductive release layer was peeled off at a 180° angle (peeling speed 0.3 m / min) using a tensile testing machine, and the peeling force (unit: N / 25mm) was measured. The measurement results are shown in Table 1. A smaller peeling force indicates higher release properties of the release layer.

[0066] [Adhesion] For each example of conductive film, the surface of the conductive release layer was rubbed 10 times with a finger, and the degree of damage to the conductive release layer was evaluated according to the following criteria. The results are shown in Table 1. (Evaluation 1): The conductive release layer completely detaches after 5 finger rubs, losing its conductivity and ease of peeling. In other words, the adhesion between the conductive release layer and the PET film is poor. (Evaluation 2): The conductive release layer remains for up to 5 finger rubs, but after that, by the 10th finger rub, the conductive release layer completely falls off, and the conductivity and ease of peeling are lost. In other words, the adhesion between the release layer and the PET film is poor. (Evaluation 3): The conductive release layer did not detach after 10 finger rubs, but a significant change in the color of the conductive release layer was observed, and its conductivity and ease of peeling decreased. In other words, the adhesion between the conductive release layer and the PET film is average. (Evaluation 4): The conductive release layer did not detach even after 10 finger rubs, and although there was a slight change in the color of the conductive release layer, the conductivity and ease of peeling were hardly reduced. In other words, the adhesion between the conductive release layer and the PET film is excellent. (Evaluation 5): The conductive release layer did not detach even after 10 finger rubs, no change in the color of the conductive release layer was observed, and its conductivity and ease of peeling did not decrease. In other words, the adhesion between the conductive release layer and the PET film is particularly excellent. In the five-level evaluation criteria described above, ease of peeling (release properties) is based on the results of a test that measures how easily adhesive tape can be peeled off a surface that has been rubbed with a finger. The discoloration of the conductive release layer indicates the degree of peeling at the interface between the conductive release layer and the PET film. If this interface is partially peeled, the interface lifts up when the adhesive tape attached to the surface of the conductive release layer is peeled off, reducing the peelability.

[0067] [Table 1]

[0068] The conductive polymer dispersions of Examples 1 to 8 contain a silicone emulsion and a water-dispersible polyester resin (excluding those containing alkoxysilyl groups), and therefore the conductive release layer formed from the coating film has good conductivity and release properties, and the conductive release layer has excellent adhesion to the substrate. The conductive polymer dispersion of Example 8 has improved wettability to the substrate due to the inclusion of a basic compound. The paint in Comparative Example 1, lacking a conductive composite, exhibits inferior conductivity and release properties in the formed coating film. This result demonstrates that the conductive composite improves the release properties of the silicone emulsion in the example. The conductive polymer dispersion in Comparative Example 2 does not contain a silicone emulsion, and therefore the mold release properties of the formed conductive layer are significantly poor. The conductive polymer dispersion of Comparative Example 3 does not contain a water-dispersible polyester resin, and therefore exhibits poor adhesion of the formed conductive layer to the substrate. Examples 1-7 are for reference only.

Claims

1. A conductive polymer dispersion containing a conductive composite comprising a π-conjugated conductive polymer and a polyanion, a silicone emulsion, a water-dispersible polyester resin, an aqueous dispersion medium, and a basic compound. The π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene), and the polyanion is polystyrene sulfonic acid. The content of the conductive composite is 0.15% by mass or more and 1.0% by mass or less, relative to the total mass of the conductive polymer dispersion. The solid content of the silicone emulsion is 0.5% by mass or more and 3.5% by mass or less, relative to the total mass of the conductive polymer dispersion. The content of the water-dispersible polyester resin is 100 parts by mass or more and 2000 parts by mass or less per 100 parts by mass of the conductive composite. The content of the water-dispersible polyester resin is 30 parts by mass or more and 500 parts by mass or less per 100 parts by mass of the solid content of the silicone emulsion. The water content per 1 part by mass of the conductive composite is 80 parts by mass or more and 400 parts by mass or less. The aqueous dispersion medium contains a water-soluble organic solvent, and the content ratio of the water-soluble organic solvent to the total mass of the aqueous dispersion medium is 60% by mass or more and 85% by mass or less. The basic compound is an inorganic alkali, and the content of the inorganic alkali relative to the total mass of the conductive polymer dispersion is 1 mM or more and 10 mM or less. Conductive polymer dispersion.

2. The conductive polymer dispersion according to claim 1, further comprising a platinum-based catalyst.

3. The conductive polymer dispersion according to claim 1, wherein the content of the polyanion in the conductive composite is in the range of 100 parts by mass or more and 500 parts by mass or less per 100 parts by mass of the π-conjugated conductive polymer.

4. The system comprises a base material and a conductive release layer formed on at least a portion of the surface of the base material. A conductive laminate wherein the conductive release layer is a cured product of a conductive polymer dispersion according to any one of claims 1 to 3.

5. The conductive laminate according to claim 4, wherein the substrate is a polyethylene terephthalate film.

6. A method for producing a conductive laminate, comprising coating at least a portion of the surface of a substrate with a conductive polymer dispersion according to any one of claims 1 to 3 to form a conductive layer.

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