Conductive laminate and method for manufacturing the same

Abstract

To provide a conductive laminate comprising laminated two conductive layers that feature superior conductivity, high adhesion to substrates, resistance to organic solvents that can come from external sources, and high hardness, and a method for producing the same.SOLUTION: A conductive laminate includes a substrate, a conductive layer A laminated on at least some surface of the substrate, and a conductive layer B laminated on the surface of the conductive layer A. The conductive layer A includes a conductive polymer and an organic binder. The conductive layer B includes a conductive polymer and an inorganic binder. The sole surface resistance of the conductive layer B is less than 100 ΩM / sq.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a conductive laminate having two conductive layers containing a conductive polymer, and a method for producing the same. [Background technology]

[0002] Conventionally, conductive polymer dispersions containing a conductive composite in which poly(3,4-ethylenedioxythiophene) is doped with polystyrene sulfonic acid are sometimes used as coatings for forming conductive layers. For example, Patent Document 1 discloses a conductive polymer dispersion containing a conductive composite, an acrylamide compound, and a dispersion medium, but without a radical polymerization initiator for initiating the polymerization of acrylamide. According to this invention, by incorporating the acrylamide compound, which was conventionally polymerized, into the conductive layer in an unpolymerized state, excellent conductivity and other properties can be achieved. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-127397 [Overview of the project] [Problems that the invention aims to solve]

[0004] Incidentally, conductive layers formed on the surface of substrates such as films are sometimes required to possess not only excellent conductivity, but also adhesion to the substrate surface, resistance to organic solvents, and high hardness. However, conventionally, a conductive layer that can exhibit these properties in a balanced manner has not been realized.

[0005] The present invention provides a conductive laminate comprising two laminated conductive layers exhibiting excellent conductivity, high adhesion to a substrate, resistance to organic solvents that may come into contact with the outside, and high hardness, as well as a method for manufacturing the same. [Means for solving the problem]

[0006] [1] A conductive laminate comprising a substrate, a conductive layer A laminated on at least a portion of the surface of the substrate, and a conductive layer B laminated on the surface of the conductive layer A, wherein the conductive layer A comprises a conductive polymer and an organic binder, and the conductive layer B comprises a conductive polymer and an inorganic binder, and the surface resistance of the conductive layer B alone is less than 100 MΩ / sq. [2] The conductive laminate according to [1], wherein the conductive polymer contained in the conductive layer A and the conductive layer B is a π-conjugated conductive polymer, and the π-conjugated conductive polymer forms a conductive composite with a sulfonic acid group-containing polymer. [3] The conductive laminate according to [1] or [2], wherein the organic binder comprises a polyester resin. [4] The conductive laminate according to any one of [1] to [3], wherein the inorganic binder comprises a condensate of an alkoxysilane. [5] The conductive laminate according to any one of [2] to [4], wherein the content of the organic binder in the conductive layer A is 1 to 10 times by mass relative to the content of the conductive composite. [6] The conductive laminate according to any one of [2] to [5], wherein the content of the inorganic binder in the conductive layer B is 10 to 60 times by mass relative to the content of the conductive composite. [7] Surface resistance value R of the conductive layer A alone A The surface resistance value R of the conductive layer B alone is B A conductive laminate described in any one of the following items [1] to [6], which is lower than [1]. [8] The method for manufacturing a conductive laminate according to any one of [1] to [7], comprising: applying a paint A containing the conductive polymer, the organic binder, and a dispersion medium to at least a part of the surface of the substrate, and drying the coating film to form the conductive layer A; and applying a paint B containing the conductive polymer, the inorganic binder, and a dispersion medium to the surface of the conductive layer A, and drying the coating film to form the conductive layer B, wherein the paint A contains a high-boiling solvent having a boiling point of 150 °C or higher at 1 atm, and the content of the high-boiling solvent with respect to the total mass of the paint A is 1% by mass or more. [9] The method for manufacturing a conductive laminate according to [8], wherein the paint B contains water as the dispersion medium, the content of water with respect to the total mass of the paint B is 30% by mass or more, and the inorganic binder in the coating film is cured by heating the coating film formed by applying the paint B.

[10] The method for manufacturing a conductive laminate according to [8] or [9], wherein at least one of the paint A and the paint B contains a surfactant.

Advantages of the Invention

[0007] In the conductive laminate of the present invention, since it has two laminated conductive layers exhibiting excellent conductivity, high adhesion to the substrate, resistance to organic solvents that can come into contact from the outside, and high hardness, it has excellent durability in various use environments. According to the method for manufacturing a conductive laminate of the present invention, a conductive laminate excellent in the balance of the above characteristics can be manufactured.

[0008] The present invention is considered to contribute to SDGs Goal 12, "Responsibility for Production and Consumption".

[0009] In this specification and the claims, the lower and upper limit values of the numerical range indicated by "~" are included in the numerical range.

Embodiments for Carrying Out the Invention

[0010] ≪Method for Manufacturing a Conductive Laminate≫ The first aspect of the present invention is a method for manufacturing a conductive laminate, which can manufacture the conductive laminate of the second aspect described below. The first aspect comprises at least the following two steps A and B. Step A is a step of applying paint A, which contains a conductive polymer, an organic binder, and a dispersion medium, to at least a portion of the surface of the substrate, and drying the paint film to form a conductive layer A. Step B is a step of applying paint B, which contains a conductive polymer, an inorganic binder, and a dispersion medium, to at least a portion of the surface of the conductive layer A, and drying the paint film to form the conductive layer B.

[0011] <Process A> The conductive polymer contained in paint A is not particularly limited, but a π-conjugated conductive polymer is preferred from the viewpoint of enhancing conductivity.

[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 π-conjugated conductive polymer contained in paint A may be one type or two or more types.

[0014] (Conductive composite) From the viewpoint of improving the dispersibility of the π-conjugated conductive polymer in paint A, it is preferable that the π-conjugated conductive polymer is doped with polyanions to form a conductive composite. The polyanions in the conductive composite dope the π-conjugated conductive polymer, thereby enhancing its conductivity. Furthermore, only a portion of the polyanions' anionic groups dope 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 exhibits water dispersibility. The conductive composite in paint A may be in a dispersed state or a dissolved state. In this specification, the dispersed state and the dissolved state are not distinguished unless otherwise specified.

[0015] (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. A polyanion having a sulfo group can be rephrased as a sulfonic acid group-containing polymer. Specific examples of such polyanions include polystyrene sulfonic acid, polyvinyl sulfonic acid, polyallyl sulfonic acid, polyacrylic acid esters having sulfo groups, polymethacrylic acid esters having sulfo groups (for example, poly(4-sulfobutyl methacrylate, polysulfoethyl methacrylate, polymethacryloyloxybenzene sulfonic acid), poly(2-acrylamido-2-methylpropanesulfonic acid), polyisoprene sulfonic acid, and other polymers having sulfo groups, as well as polymers having carboxyl groups such as polyvinyl carboxylic acid, polystyrene carboxylic acid, polyallyl carboxylic acid, polyacrylic acid, polymethacrylic acid, poly(2-acrylamido-2-methylpropanecarboxylic acid), and polyisoprene carboxylic acid. Polyanions may be homopolymers formed by the polymerization of a single monomer, or copolymers formed by the polymerization of two or more monomers. Among these polyanions, polymers having sulfo groups are preferred because they can achieve higher conductivity, and polystyrene sulfonic acid is even more preferred. The conductive composite may consist of one type of polyanion or two or more types. The mass-average molecular weight of the polyanion is preferably between 20,000 and 1,000,000, and more preferably between 100,000 and 500,000. The mass-average molecular weight is the average molecular weight on a mass basis, determined by measuring it using gel filtration chromatography and converting it to pullulan equivalent.

[0016] The polyanion content in the conductive composite is preferably in the range of 1 to 1000 parts by mass, more preferably 10 to 700 parts by mass, and even more preferably 100 to 500 parts by mass, per 100 parts by mass of the π-conjugated conductive polymer. If the polyanion content is above 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, the π-conjugated conductive polymer can be sufficiently contained, thus ensuring sufficient conductivity.

[0017] The content of the conductive composite relative to the total mass of paint A is preferably 0.01% by mass or more and 2% by mass or less, more preferably 0.05% by mass or more and 1% by mass or less, and even more preferably 0.1% by mass or more and 0.5% by mass or less. If the value is above the lower limit of the above range, the conductivity of the conductive layer formed by applying paint A can be further improved. If the value is below the upper limit of the above range, the dispersibility of the conductive composite in paint A can be improved, and a uniform conductive layer can be formed.

[0018] (Organic binder) The organic binder contained in paint A is an organic resin (a polymer mainly composed of carbon-carbon bonds) other than the π-conjugated conductive polymer and the polyanion, or a precursor thereof, and is a thermoplastic resin, or a curable monomer or oligomer that hardens when the conductive layer is formed. The thermoplastic resin becomes the binder resin as is, and the resin formed by the hardening of the curable monomer or oligomer becomes the binder resin. Paint A may contain one type of organic binder, or two or more types.

[0019] Specific examples of binder resins include, for example, acrylic resin (acrylic compound), polyester resin, polyurethane resin, polyimide resin, polyether resin, melamine resin, and polyvinyl alcohol. The binder resin contained in paint A is preferably a water-dispersible resin, and more preferably a water-dispersible emulsion resin. The water-dispersible resin is an emulsion resin or a water-soluble resin.

[0020] Specific examples of water-dispersible emulsion resins include acrylic resins (acrylic compounds), polyester resins, polyurethane resins, polyimide resins, melamine resins, etc., which are emulsions formed with emulsifiers.

[0021] Since the adhesion strength of the coating film applied to the substrate by coating A is increased, the binder resin preferably contains a polyester resin, and more preferably contains a polyester resin emulsion. In particular, when coating a polyester film substrate, it is preferable to include a polyester resin or its emulsion because the adhesion of the coating film to the substrate becomes even higher.

[0022] Specific examples of water-soluble resins include acrylic resins (acrylic compounds), polyester resins, polyurethane resins, polyimide resins, and melamine resins, which have acidic groups such as carboxyl groups and sulfol groups, or salts thereof. Here, the water-soluble resin is one that dissolves in 100g of distilled water at 25°C in amounts of 1g or more, preferably 5g or more, and more preferably 10g or more. The acidic groups such as carboxyl groups and sulfol groups of the water-soluble resin may form salts with cations such as sodium ions and potassium ions.

[0023] The organic binder may be a curable monomer or oligomer, which may be a thermosetting monomer or oligomer, or a photocurable monomer or oligomer. Here, an oligomer is a polymer with a mass-average molecular weight of less than 10,000. Polymers with a mass-average molecular weight of more than 10,000 do not have curability. Examples of curable monomers include acrylic monomers (acrylic compounds) and epoxy monomers. Examples of curable oligomers include acrylic oligomers (acrylic compounds) and epoxy oligomers. When acrylic monomers or acrylic oligomers are used as organic binders, the material can be easily cured by heating or light irradiation.

[0024] If the material contains a curable monomer or oligomer, it is preferable to further include a curing catalyst. For example, if the material contains a thermosetting monomer or oligomer, it is preferable to include a thermal polymerization initiator that generates radicals upon heating, and if the material contains a photocurable monomer or oligomer, it is preferable to include a photopolymerization initiator that generates radicals upon light irradiation.

[0025] The content of the organic binder in paint A is preferably 0.1 to 20 times, more preferably 0.5 to 15 times, and even more preferably 1.0 to 10 times, by mass, the content of the conductive composite in paint A. If the value is above the lower limit of the above range, it is possible to improve the film-forming properties and film strength of the coating when applying paint A to the substrate, and further improve the adhesion of the coating to the substrate surface and conductive layer B. If the value is below the upper limit of the above range, the decrease in conductivity due to a decrease in the content of conductive polymer can be suppressed.

[0026] (dispersion medium) Examples of dispersion media included in paint A include water, organic solvents, and mixtures of water and organic solvents.

[0027] 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. Examples of ether-based solvents include diethyl ether and dimethyl 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. Organic solvents may be used individually or in combination of two or more types.

[0028] Since conductive composites containing polyanions have high dispersibility in water, it is preferable that the dispersion medium of paint A in this embodiment is an aqueous dispersion medium containing water. The water content relative to the total mass of paint A is preferably 40% by mass or more, more preferably 50% by mass or more and 90% by mass or less, and even more preferably 60% by mass or more and 80% by mass or less. With the above-mentioned preferred content, a conductive layer with excellent adhesion to the substrate surface and conductive layer B can be easily formed.

[0029] (High boiling point solvent) Paint A preferably contains, in addition to water, a high-boiling-point solvent whose boiling point at 1 atmosphere is in the range of 150°C to 250°C. Including a high-boiling-point solvent provides effects such as improved conductivity and suppression of shrinkage during drying of the paint film. Paint A may contain one or more types of high-boiling point solvents.

[0030] Examples of high-boiling point solvents include alcohol-based solvents, ether-based solvents, ketone-based solvents, nitrogen atom-containing solvents, and sulfur atom-containing solvents. Examples of alcohol-based solvents include polyhydric alcohols such as ethylene glycol (boiling point 197°C), 1,2-propanediol (also known as propylene glycol, boiling point 188°C), 1,3-propanediol (boiling point 214°C), 1,2-butanediol (boiling point 194°C), 1,3-butanediol (boiling point 207°C), 1,4-butanediol (boiling point 228°C), dipropylene glycol (boiling point 232°C, mixture of isomers), 2-butyn-1,4-diol (boiling point 238°C), and diethylene glycol (boiling point 245°C). Examples of ether-based solvents include diethylene glycol dimethyl ether (boiling point 162°C) and diethylene glycol diethyl ether (boiling point 188°C). Examples of ketone-based solvents include methyl amyl ketone (boiling point 151°C) and diacetone alcohol (boiling point 168°C). Examples of nitrogen atom-containing solvents include N-methylpyrrolidone (boiling point 202°C), N-methylacetamide (boiling point 206°C), dimethylacetamide (boiling point 165°C), N,N-dimethylformamide (boiling point 153°C), and N,N-dimethylacrylamide (boiling point 171°C). Examples of sulfur atom-containing solvents include dimethyl sulfoxide (boiling point 189°C).

[0031] The amount of high-boiling point solvent relative to the total mass of paint A is preferably 1% by mass or more, more preferably 2 to 20% by mass, and even more preferably 3 to 10% by mass. If the value is above the lower limit of the above range, the conductivity of the formed conductive layer will be further improved. If the value is below the upper limit of the above range, the drying time of the coating film will not become excessively long.

[0032] (Surfactants) Paint A preferably contains one or more surfactants. The inclusion of surfactants increases the wettability to the substrate surface, allowing for the formation of a conductive layer of uniform thickness. As a result, a conductive layer with excellent conductivity and adhesion to the substrate surface can be easily formed.

[0033] The surfactant is preferably an acetylene-based surfactant. An acetylene-based surfactant is a nonionic compound having at least one triple bond between carbon atoms in its molecule. Suitable acetylene-based surfactants include, for example, wetting agents manufactured by Nisshin Chemical Industry Co., Ltd., such as Dynol 604, Dynol 607, Surfinol 104E, Surfinol 104H, Surfinol 104A, Surfinol 104PA, Surfinol 104S, Surfinol 420, Surfinol 440, Surfinol 465, Surfinol 485, Surfinol SE, Surfinol SE-F, Surfinol PSA-336, and Surfinol 2502.

[0034] The number of carbon atoms in the molecule of an acetylene-based surfactant is preferably 11 to 100, more preferably 12 to 70, even more preferably 13 to 50, and most preferably 14 to 40. Wettability is further improved when the number of carbon atoms falls within these preferred ranges. Acetylene-based surfactants preferably have a hydroxyl group or an oxygen atom constituting an ether bond within their molecule. The presence of an oxygen atom further improves wettability.

[0035] The surfactant content relative to the total mass of paint A is preferably 0.0001% by mass or more and 0.5% by mass or less, more preferably 0.001% by mass or more and 0.1% by mass or less, and even more preferably 0.005% by mass or more and 0.05% by mass or less. With the above-mentioned preferred content, the wettability to the substrate surface is further enhanced, and a conductive layer of uniform thickness can be formed. As a result, a conductive layer with superior conductivity and adhesion to the substrate surface can be formed more easily.

[0036] (Alkoxysilane) Paint A may contain one or more alkoxysilanes. Here, an alkoxysilane is a compound having 1 to 4 alkyl groups (alkoxy groups) bonded to a silicon atom with an oxygen atom interposed therebetween. The number of carbon atoms in the alkyl group is preferably 1 to 6, and more preferably 1 to 3. The alkyl group may be linear or branched. In addition to the alkoxy group, one to three alkyl groups may be directly bonded to the silicon atom. The alkyl group directly bonded to the silicon atom preferably has 1 to 6 carbon atoms, and more preferably 1 to 3 carbon atoms. The alkyl group may be linear or branched.

[0037] Examples of alkoxysilanes include tetraalkoxysilanes and trialkoxysilanes. The number of carbon atoms in each alkyl group constituting the alkoxy group of the tetraalkoxysilane is preferably 1 to 6, and more preferably 1 to 3. The alkyl group may be linear or branched. The number of carbon atoms in each alkyl group constituting the alkoxysilane is preferably 1 to 6, and more preferably 1 to 3, independently. The alkyl group may be linear or branched. In addition to the alkoxysilane, it is preferable that the silicon atom of the trialkoxysilane has a hydrogen atom or an alkyl group bonded to it. The number of carbon atoms of the alkyl group directly bonded to the silicon atom is preferably 1 to 6, and more preferably 1 to 3. The alkyl group may be linear or branched.

[0038] Examples of tetraalkoxysilanes include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetraisopropoxysilane. Examples of trialkoxysilanes include methyltriethoxysilane, ethyltriethoxysilane, and propyltriethoxysilane.

[0039] When paint A contains alkoxysilane, the amount of alkoxysilane in paint A is preferably 0.01 to 0.7 times, more preferably 0.05 to 0.5 times, and even more preferably 0.1 to 0.3 times, by mass, relative to the amount of organic binder in paint A. Within the above preferred range, the mechanical strength of the conductive layer due to the addition of alkoxysilane can be increased without impairing the properties of the organic binder.

[0040] (Other additives) Paint A may contain other additives. The additives are not particularly limited as long as the effects of the present invention are achieved, and for example, surfactants, defoamers, antioxidants, ultraviolet absorbers, etc., can be used. However, the additives are those other than the π-conjugated conductive polymers, polyanions, high-boiling point solvents, acetylene-based surfactants, and dispersion media mentioned above. 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 defoaming agents include silicone resins, polydimethylsiloxanes, and silicone oils. Examples of antioxidants include phenolic antioxidants, amine antioxidants, phosphorus antioxidants, sulfur antioxidants, sugars, gallic acid or its esters, etc. 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.

[0041] If paint A 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 50 parts by mass or less per 100 parts by mass of conductive composite.

[0042] [Base material] The substrate constituting the conductive laminate may be made of an insulating material or a conductive material. The shape of the substrate is not particularly limited, and examples include mainly planar 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.

[0043] (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 layer, the synthetic resin for the film substrate is preferably the same type of resin as the organic binder, and among these, polyester resins such as polyethylene terephthalate are preferred.

[0044] 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 to further improve the adhesion of the conductive layer.

[0045] 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 the average of the measurements taken at 10 randomly selected locations.

[0046] [apply] Methods for applying (coating) paint A 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.

[0047] The amount of paint A applied to the substrate is not particularly limited, but considering the need for uniform and even coating, as well as conductivity and film strength, the solid content is approximately 1.0 g / m². 2 More than 100.0g / m 2 The following range is preferable. Furthermore, it is preferable to apply the coating to a film thickness such that the conductive layer A formed after drying is 0.1 to 2 μm thick. In this case, the thickness of the coating film is preferably, for example, 0.3 to 4 μm.

[0048] A conductive layer A can be formed by drying a coating film made of paint A applied to a substrate, removing at least a portion of the dispersion medium, and curing it. Methods for drying the coating 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. After drying, if necessary, the organic binder may be cured by irradiating it with active energy rays such as UV light.

[0049] <Process B> The conductive polymer contained in paint B is not particularly limited, but a π-conjugated conductive polymer is preferred from the viewpoint of enhancing conductivity. Examples of π-conjugated conductive polymers are the same as those exemplified in paint A. The conductive polymer contained in paint B may be the same as or different from the conductive polymer contained in paint A.

[0050] From the viewpoint of improving the dispersibility of the π-conjugated conductive polymer in paint B, it is preferable that the π-conjugated conductive polymer is doped with polyanions to form a conductive composite. The explanation of polyanions and conductive composites in paint B is the same as the explanation of polyanions and conductive composites in paint A, so redundant explanations are omitted here.

[0051] The content of the conductive composite relative to the total mass of paint B is preferably 0.01% by mass or more and 2% by mass or less, more preferably 0.05% by mass or more and 1% by mass or less, and even more preferably 0.1% by mass or more and 0.5% by mass or less. If the value is above the lower limit of the above range, the conductivity of the conductive layer formed by applying paint B can be further improved. If the value is below the upper limit of the above range, the dispersibility of the conductive composite in paint B can be improved, and a uniform conductive layer can be formed.

[0052] (Inorganic binder) The inorganic binder contained in paint B is an inorganic compound (inorganic polymer) or precursor thereof, mainly composed of silicon-oxygen-silicon bonds or silicon-silicon bonds. As inorganic binders, alkoxysilanes and silicates are preferred. An example of an alkoxysilane is the one exemplified in paint A. The alkoxysilane contained in paint B may be the same as or different from the alkoxysilane contained in paint A.

[0053] An alkoxysilane is any compound that has one silicon atom in its molecule, to which one or more alkoxy groups are bonded. Since alkoxysilanes are readily hydrolyzed, it is preferable that they have a methoxy group or an ethoxy group. The alkoxysilane contained in paint B may have functional groups other than the alkoxy group, such as an epoxy group, an allyl group, a vinyl group, a glycidyl group, etc. Specific preferred alkoxysilanes include, for example, tetramethoxysilane, tetraethoxysilane, methyltriethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane. To promote the reaction of functional groups other than alkoxy groups, an appropriate amount of catalyst such as hydrochloric acid may be added.

[0054] A silicate is a compound having two or more silicon atoms in one molecule, in which at least one pair of silicon atoms are ether-bonded via one oxygen atom. The number of silicon atoms in one molecule of silicate is preferably four or more, more preferably six or more, and even more preferably eight or more, as this increases the hardness of the conductive layer formed from paint B. Furthermore, from the viewpoint of improving the solubility of silicate in paint B, the number of silicon atoms in one molecule of silicate is preferably 40 or less, and more preferably 30 or less. The content of SiO2 units in the silicate is preferably 15% by mass or more and 70% by mass or less, more preferably 25% by mass or more and 50% by mass or less, based on the total mass of the silicate. If the content of SiO2 units in the silicate is at least the lower limit value, the hardness of the conductive layer formed from Paint B becomes higher. If it is at most the upper limit value, it is possible to prevent a decrease in the conductivity of the conductive layer. Here, the content of SiO2 units in the silicate is the ratio of the mass of SiO2 units (-O-Si-O- units) contained in the silicate to 100% by mass of the molecular weight of the silicate, and can be measured by elemental analysis.

[0055] The silicate is preferably a compound represented by the following chemical formula (X). (X)… R 3 O-[(R 4 O-)(R 5 O-)Si-O-] s -R 6

[0056] In formula (X), R 3 , R 4 , R 5 , and R 6 are each independently a linear or branched alkyl group having 1 to 4 carbon atoms, and s is an integer of 2 to 100. Examples of the alkyl group having 1 to 4 carbon atoms may be linear or branched, and specifically include a methyl group, an ethyl group, a propyl group, and a butyl group. s is preferably 2 to 50, more preferably 3 to 25, and even more preferably 4 to 10.

[0057] The silicate is more preferably at least one of a compound represented by the following chemical formula (x1) and a compound represented by the following chemical formula (x2). (x1)… Si m O m-1 (OCH3) 2m+2 (x2)… Si n O n-1 (OCH2CH3) 2n+2 In the above equations (x1) and (x2), m is between 2 and 100, and n is between 2 and 100. In the above equations (x1) and (x2), Si and O are bonded together, but Si atoms are not adjacent to each other, and O atoms are not adjacent to each other.

[0058] The inorganic binder content in paint B is preferably 2 to 100 times, more preferably 10 to 80 times, and even more preferably 15 to 60 times, by mass, relative to the conductive composite content in paint B. Here, the inorganic binder content is expressed as the solid content concentration on an SiO2 basis or the solid content concentration on a condensation reaction basis. If the value is above the lower limit of the above range, the film strength of the coating can be improved, and the hardness and solvent resistance of conductive layer B can be further enhanced. If the value is below the upper limit of the above range, it is possible to suppress the film-forming properties when applying paint B to the surface of conductive layer A, and the decrease in conductivity due to a decrease in the content of conductive polymer.

[0059] Paint B may contain silica as an additive from the viewpoint of improving the hardness and solvent resistance of conductive layer B. Colloidal silica (silica sol) is preferred as the silica from the viewpoint of dispersibility. The silica content relative to the total mass of paint B is preferably 1 to 10% by mass. If paint B contains silica, it is preferable to also contain aluminum acetylacetonate. The content of aluminum acetonate relative to the total mass of paint B is preferably 0.1 to 1.0% by mass. By including aluminum acetylacetonate, the hardness and solvent resistance of conductive layer B can be further enhanced.

[0060] (dispersion medium) Examples of dispersion media included in paint B include water, organic solvents, and mixtures of water and organic solvents. Specific examples of dispersion media are those exemplified for paint A. The dispersion media included in paint B may be the same as or different from the dispersion media included in paint A.

[0061] When paint B contains water as a dispersion medium, the water content relative to the total mass of paint B is preferably 30% by mass or more, more preferably 35-60% by mass, and even more preferably 40-50% by mass. By including a suitable amount of water in paint B, the inorganic binders within the paint film can be reacted and cured by heating the paint film after applying paint B. When paint B contains water, it is preferable to include a monohydric alcohol-based solvent (excluding high-boiling point solvents) as a dispersion medium from the viewpoint of improving coatability and film-forming properties. The content of the monohydric alcohol-based solvent relative to the total mass of paint B is preferably 10 to 50% by mass, and more preferably 20 to 40% by mass.

[0062] (High boiling point solvent) Paint B preferably further contains a high-boiling-point solvent whose boiling point at 1 atmosphere is in the range of 150°C to 250°C. Including a high-boiling-point solvent provides effects such as improved conductivity and suppression of shrinkage during drying of the paint film. Specific examples of high-boiling point solvents are those exemplified in paint A. The high-boiling point solvent contained in paint B may be the same as or different from the high-boiling point solvent contained in paint A. Paint B may contain one or more types of high-boiling point solvents.

[0063] The amount of high-boiling point solvent relative to the total mass of paint B is preferably 1% by mass or more, more preferably 2 to 20% by mass, and even more preferably 3 to 10% by mass. If the value is above the lower limit of the above range, the conductivity of the formed conductive layer will be further improved. If the value is below the upper limit of the above range, the drying time of the coating film will not become excessively long.

[0064] (Surfactants) It is preferable that paint B contains one or more surfactants. The inclusion of surfactants increases the wettability to conductive layer A, allowing for the formation of conductive layer B with a uniform thickness. As a result, conductive layer B with excellent conductivity, hardness, and solvent resistance can be easily formed. Specific examples of surfactants are those exemplified in paint A. The surfactant contained in paint B may be the same as or different from the surfactant contained in paint A. Paint B may contain one type of surfactant or two or more types.

[0065] The surfactant content relative to the total mass of paint B is preferably 0.0001% by mass or more and 0.5% by mass or less, more preferably 0.001% by mass or more and 0.1% by mass or less, and even more preferably 0.005% by mass or more and 0.05% by mass or less. With the above-mentioned preferred content, the wettability to the substrate surface is further enhanced, and a conductive layer of uniform thickness can be formed. As a result, a conductive layer with superior conductivity and adhesion to the substrate surface can be formed more easily.

[0066] (Other additives) Paint B may contain other additives. Specific examples of additives are those exemplified in paint A. The additives contained in paint B may be the same as or different from those contained in paint A. Paint B may contain one or more additives.

[0067] If paint B contains the additive, its content ratio 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 50 parts by mass or less per 100 parts by mass of conductive composite.

[0068] [apply] The method for applying (coating) paint B to the surface of conductive layer A is not particularly limited, and the methods exemplified as methods for applying paint A include those described above.

[0069] There are no particular restrictions on the amount of paint B applied to the substrate, but considering uniform and even coating, as well as conductivity and film strength, the solid content is approximately 1.0 g / m². 2 More than 100.0g / m 2 The following range is preferable. Furthermore, it is preferable to apply the coating to a film thickness such that the conductive layer B formed after drying is 0.1 to 2 μm thick. In this case, the thickness of the coating film is preferably, for example, 0.3 to 4 μm.

[0070] A conductive layer B can be formed by drying a coating film made of paint B applied to the surface of conductive layer A, removing at least a portion of the dispersion medium, and curing it. Methods for drying the coating 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.

[0071] <Methods for manufacturing paints A and B> As a method for producing paint A and paint B according to this embodiment, a conventional method for producing conductive polymer dispersions can be applied, and there are no particular limitations as long as the method can mix each material.

[0072] 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, or a commercially available one may be used.

[0073] <<Conductive Laminate>> A first aspect of the present invention is a conductive laminate comprising a substrate, a conductive layer A laminated on at least a portion of the surface of the substrate, and a conductive layer B laminated on the surface of conductive layer A. The conductive layer A in this embodiment comprises a conductive polymer and an organic binder, and may be a cured product of the aforementioned paint A. The conductive layer B in this embodiment comprises a conductive polymer and an inorganic binder, and may be a cured product of the aforementioned paint B. In this embodiment, it is preferable that the surface resistance of the conductive layer B alone is less than 100 MΩ / sq.

[0074] [Conductive layer A] The area where the conductive layer A is formed may be the entire surface of any surface of the substrate, or it may be only a part of it. If the conductive layer A is formed on only a part of the surface of the substrate, for example, the conductive layer A may be a fine conductive pattern such as a circuit or an electrode, or the area where the conductive layer A is provided and the area where it is not provided may exist on the same surface and be roughly separated.

[0075] The average thickness of the conductive layer A is preferably, for example, 10 nm to 10 μm, more preferably 20 nm to 5 μm, and even more preferably 30 nm to 3 μm. If the average thickness of the conductive layer A is greater than or equal to the lower limit, it can exhibit high conductivity, and if it is less than or equal to the upper limit, the adhesion of the conductive layer A to the substrate is further improved. The average thickness of conductive layer A is the average of the cross-sectional thickness measurements taken at 10 randomly selected locations. The cross-section of conductive layer A is observed using known magnification methods such as an electron microscope.

[0076] (Surface resistance value) The surface resistance R of conductive layer A alone A This can be, for example, 100 to 10,000 Ω / sq. Of these, 100 to 6,000 Ω / sq. is preferred, 100 to 4,000 Ω / sq. is more preferred, and 100 to 2,000 Ω / sq. is even more preferred. The surface resistance R of conductive layer A alone A When the value is within the above preferred range, the surface resistance of the entire conductive laminate after lamination of conductive layer B can be sufficiently reduced, and excellent conductivity can be achieved. Here, the surface resistance value R of the conductive layer A alone is... A This value is measured at the point when only conductive layer A is formed on the substrate surface. Surface resistance can be measured using a commercially available resistivity meter.

[0077] [Base material] The description of the substrate constituting the conductive laminate in this embodiment is the same as the description of the substrate in step A described above, so redundant explanations will be omitted here.

[0078] [Conductive layer B] The area where conductive layer B is formed may be the entire surface of conductive layer A or a part of it, but from the viewpoint of fully exhibiting solvent resistance, it is preferable that it be the entire surface of conductive layer A.

[0079] The average thickness of the conductive layer B is preferably, for example, 10 nm to 10 μm, more preferably 20 nm to 5 μm, and even more preferably 30 nm to 3 μm. If the average thickness of conductive layer B is greater than or equal to the lower limit, it can fully exhibit conductivity, mechanical strength, and solvent resistance. If it is less than or equal to the upper limit, the adhesion of conductive layer B to conductive layer A is further improved. The average thickness of conductive layer B is the average of the cross-sectional thickness measurements taken at 10 randomly selected locations. The cross-section of conductive layer B is observed using known magnification methods such as an electron microscope.

[0080] (Surface resistance value) R is the surface resistance value of conductive layer B alone. B is less than 100 MΩ / sq. (100 × 10 6 A impedance of less than Ω / sq. is preferred, less than 40 MΩ / sq. is more preferred, less than 20 MΩ / sq. is even more preferred, and less than 1 MΩ / sq. is most preferred. R is the surface resistance value of conductive layer B alone. B When the values ​​are within the above preferred range, the surface resistance of the entire conductive laminate can be sufficiently reduced, and excellent conductivity can be achieved. Here, the surface resistance value R of the conductive layer B alone is... B This value was obtained by forming only the conductive layer B on the substrate surface and measuring it. Surface resistance can be measured using a commercially available resistivity meter.

[0081] In this embodiment, the conductive polymers contained in conductive layer A and conductive layer B are preferably π-conjugated conductive polymers, and it is preferable that these π-conjugated conductive polymers form a conductive composite with a sulfonic acid group-containing polymer. With this configuration, the conductivity of the conductive laminate as a whole, achieved by laminating conductive layers A and B, adhesion to the substrate, resistance to organic solvents that may come into contact with the outside, and hardness are easily balanced at a high level.

[0082] The organic binder constituting conductive layer A preferably contains polyester resin. With this configuration, the adhesion of conductive layer A to conductive layer B and the substrate surface is excellent, and the conductivity of the conductive laminate as a whole, adhesion to the substrate, resistance to organic solvents that may come into contact with it from the outside, and hardness are easily balanced at a high level.

[0083] The inorganic binder constituting conductive layer B preferably contains an alkoxysilane condensate. This configuration not only increases the hardness and solvent resistance of conductive layer B, but also provides excellent adhesion to conductive layer A, making it easier to achieve a good balance of high levels of conductivity, adhesion to the substrate, resistance to organic solvents that may come into contact with the outside, and hardness of the conductive laminate as a whole.

[0084] In conductive layer A, the content of the organic binder is preferably 0.1 to 20 times, more preferably 0.5 to 15 times, and even more preferably 1.0 to 10 times, by mass, relative to the content of the conductive composite. With this configuration, the adhesion of conductive layer A to conductive layer B and the substrate surface is excellent, and the conductivity of the conductive laminate as a whole, adhesion to the substrate, resistance to organic solvents that may come into contact with the outside, and hardness are more easily achieved at a high level and in a well-balanced manner.

[0085] In conductive layer B, the inorganic binder content is preferably 2 to 100 times, more preferably 10 to 80 times, and even more preferably 15 to 60 times, by mass, relative to the conductive composite content. With this configuration, not only are the hardness and solvent resistance of conductive layer B increased, but the adhesion to conductive layer A is also excellent, and the conductivity of the conductive laminate as a whole, adhesion to the substrate, resistance to organic solvents that may come into contact with the outside, and hardness are more easily and more well-balanced at a high level.

[0086] [Conductive laminate and surface resistance values ​​of each layer] In the conductive laminate of this embodiment, the surface resistance value R of the conductive layer A alone A R is the surface resistance value of conductive layer B alone. B It is preferable that the value be lower than this. With this relationship, the surface resistance of the entire conductive laminate can be sufficiently reduced, and better conductivity can be achieved. Furthermore, the surface resistance value R of the entire conductive laminate in this embodiment C And the surface resistance value R of conductive layer A alone A (R C / R A The ratio expressed as ) is preferably 1.0 to 2.0, more preferably 1.0 to 1.2, and even more preferably 1.0 to 1.1. With this configuration, the surface resistance value Rc of the entire conductive laminate is equal to the surface resistance value R of the conductive layer A alone. A This fully reflects the low value, further enhancing the overall conductivity of the conductive laminate. Here, the surface resistance value R of the entire conductive laminate is... C This value was measured by bringing a measuring terminal into contact with the surface of conductive layer B of the conductive laminate. Surface resistance can be measured using a commercially available resistivity meter. [Examples]

[0087] (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, and approximately 1000 ml of the resulting polystyrene sulfonate-containing solution was removed by ultrafiltration. Next, 2000 ml of deionized water was added to the remaining solution, and approximately 2000 ml of the solution was removed by ultrafiltration to wash the polystyrene sulfonate 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 (PSS).

[0088] (Manufacturing Example 2) Production of PEDOT-PSS aqueous dispersion A solution prepared by dissolving 14.2 g of 3,4-ethylenedioxythiophene and 36.7 g of polystyrene sulfonic acid obtained in Production Example 1 in 2000 ml of deionized water was mixed at 20°C. The resulting mixture was kept at 20°C, and while stirring, a solution of 29.64 g of ammonium persulfate and 8.0 g of ferric sulfate oxidation catalyst, dissolved in 200 ml of deionized water, was slowly added, and the mixture was stirred for 3 hours to allow the reaction to proceed. 2000 ml of deionized water was added to the resulting reaction solution, and approximately 2000 ml of the solution was removed by ultrafiltration. This procedure was repeated three times. Next, 200 ml of sulfuric acid diluted to 10% by mass and 2000 ml of deionized water were added to the obtained solution, and approximately 2000 ml of the solution was removed by ultrafiltration. Then, 2000 ml of deionized water was added to this solution, and approximately 2000 ml of the solution was removed by ultrafiltration. This procedure was repeated three times. Furthermore, 2000 ml of deionized water was added to the obtained solution, and approximately 2000 ml of the solution was removed by ultrafiltration. This procedure was repeated five times to obtain a polystyrene sulfonate-doped poly(3,4-ethylenedioxythiophene) aqueous dispersion (PEDOT-PSS aqueous dispersion) with a solid content of 1.2% by mass.

[0089] (Preparation of conductive paint) The conductive paints A1 to A5 and AC1 that form the conductive layer A were prepared by the following method.

[0090] [Conductive paint A1] To 40 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 10 g of aqueous dispersion polyester resin (manufactured by Takamatsu Oil & Fat Co., Ltd., PESRESIN A645GH, solid content concentration 30% by mass) as an organic binder component, 5 g of ethylene glycol with a boiling point of 197°C, 30 g of pure water, and 15 g of methanol were added and stirred at 24°C for 1 hour. Subsequently, 0.1 g of gallic acid as a stabilizer and 0.01 g of acetylene-based surfactant (manufactured by Nisshin Chemical Industry Co., Ltd., Dynol 604) as a surface modifier were added and stirred for another hour to obtain conductive paint A1. The binder content of conductive paint A1 is 6.3 times the weight of the conductive composite (PEDOT-PSS).

[0091] [Conductive paint A2] To 20 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 10 g of aqueous dispersion polyester resin (Takamatsu Oil & Fat Co., Ltd., PESRESIN A645GH, solid content concentration 30% by mass) as an organic binder component, 5 g of aqueous polyvinyl alcohol solution (Kuraray Co., Ltd., Kuraray POVA-217, solid content concentration 10% by mass), 5 g of ethylene glycol with a boiling point of 197°C, 40 g of pure water, and 25 g of methanol were added and stirred at 24°C for 1 hour. Subsequently, 0.1 g of gallic acid as a stabilizer and 0.01 g of acetylene-based surfactant (Nisshin Chemical Industry Co., Ltd., Surfinol 420) as a surface modifier were added and stirred for another hour to obtain conductive paint A2. The binder content of conductive paint A2 is 8.3 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0092] [Conductive paint A3] To 15 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 6 g of aqueous dispersion polyester resin (manufactured by Go-o Chemical Industry Co., Ltd., RZ-105, solid content concentration 25% by mass) as an organic binder component, 1 g of tetraethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBE-04, solid content concentration 29% by mass in terms of SiO2) as an inorganic binder component, 5 g of N,N-dimethylacrylamide with a boiling point of 171°C, 23 g of pure water, and 50 g of ethanol were added and stirred at 24°C for 3 hours. Subsequently, 0.1 g of gallic acid as a stabilizer and 0.01 g of acetylene-based surfactant (manufactured by Nisshin Chemical Industry Co., Ltd., Dynol 604) as a surface modifier were added and stirred for a further 1 hour to obtain conductive paint A3. The binder content of conductive paint A3 is 9.9 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0093] [Conductive paint A4] To 55 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 10 g of aqueous dispersion polyester resin (manufactured by Takamatsu Oil & Fat Co., Ltd., PESRESIN A125S, solid content concentration 30% by mass), 2 g of 2-butyne-1,4-diol with a boiling point of 238°C, 18 g of pure water, and 15 g of methanol were added as organic binder components, and the mixture was stirred at 24°C for 1 hour. Subsequently, 0.1 g of gallic acid was added as a stabilizer and 0.01 g of acetylene-based surfactant (manufactured by Nisshin Chemical Co., Ltd., Dynol 604) was added as a surface modifier, and the mixture was stirred for another hour to obtain conductive paint A4. The binder content of conductive paint A4 is 4.5 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0094] [Conductive paint A5] To 25 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 3 g of aqueous dispersion polyester resin (manufactured by Go-o Chemical Industry Co., Ltd., RZ-570, solid content concentration 25% by mass), 7 g of propylene glycol with a boiling point of 188°C, 40 g of pure water, and 25 g of methanol were added as organic binder components, and the mixture was stirred at 24°C for 1 hour. Then, 0.1 g of gallic acid was added as a stabilizer, and the mixture was stirred for another hour to obtain conductive paint A5. The binder content of conductive paint A5 is 3.0 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0095] [Conductive paint AC1] To 25 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 5 g of ethylene glycol with a boiling point of 197°C, 43 g of pure water, and 20 g of methanol were added. 7 g of tetraethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-04, SiO2 equivalent solid content concentration 29% by mass) was slowly added as an inorganic binder component, and the mixture was stirred at 24°C for 5 hours. Subsequently, 0.05 g of bis(4-hydroxyphenyl) sulfide (Tokyo Chemical Industries, Ltd.) was added as a stabilizer, and 0.01 g of acetylene-based surfactant (Nisshin Chemical Industry Co., Ltd., Surfinol 420) was added as a surface modifier. The mixture was stirred for another hour to obtain conductive paint AC1. The binder content of conductive paint AC1 is 6.8 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0096] Similarly, conductive paints B1-B3 and BC1-BC2, which form the conductive layer B, were prepared using the following method.

[0097] [Conductive paint B1] To 10 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 5 g of propylene glycol with a boiling point of 188°C, 35 g of pure water, and 43 g of methanol were added. 7 g of tetraethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-04, SiO2 equivalent solid content concentration 29% by mass) was slowly added as an inorganic binder component, and the mixture was stirred at 24°C for 3 hours. Subsequently, 0.05 g of bis(4-hydroxyphenyl) sulfide (Tokyo Chemical Industries, Ltd.) was added as a stabilizer, and 0.01 g of acetylene-based surfactant (Nisshin Chemical Industry Co., Ltd., Surfinol 420) was added as a surface modifier. The mixture was stirred for another hour to obtain conductive paint B1. The binder content of conductive paint B1 is 16.9 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0098] [Conductive paint B2] To 10 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 5 g of N,N-dimethylacrylamide (boiling point 171°C), 35 g of pure water, and 43 g of methanol were added. 6 g of tetraethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-04, SiO2 equivalent solid content concentration 29% by mass) and 1 g of methyltriethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-13, condensation reaction product equivalent solid content 38% by mass) were slowly added as inorganic binder components, and the mixture was stirred at 24°C for 3 hours. Subsequently, 0.05 g of bis(4-hydroxyphenyl) sulfide (Tokyo Chemical Industries Co., Ltd.) was added as a stabilizer, and 0.01 g of acetylene-based surfactant (Nisshin Chemical Industry Co., Ltd., Surfinol 420) was added as a surface modifier, and the mixture was stirred for another hour to obtain conductive paint B2. The binder content of conductive paint B2 is 18.4 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0099] [Conductive paint B3] 5 g of propylene glycol with a boiling point of 188°C and 20 g of methanol were mixed. 4.2 g of tetraethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-04, SiO2 equivalent solid content concentration 29% by mass) and 8 g of 3-glycidoxypropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., KBM-403, condensation reaction product equivalent solid content 71% by mass) were added as inorganic binder components. 4 g of 0.05 N hydrochloric acid was added as a catalyst, and the mixture was stirred at 24°C for 16 hours. Subsequently, 15 g of silica sol (Nissan Chemical Corporation, Snowtex ST-O-40, solid content concentration 40% by mass) was slowly added, and 23.5 g of pure water, 0.3 g of aluminum acetylacetonate, and 20 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2 were added. The mixture was stirred at 24°C for 30 minutes to obtain conductive paint B3. The binder content of conductive paint B3 is 53.7 times the weight of the conductive composite (PEDOT-PSS).

[0100] [Conductive paint BC1] To 5 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 34 g of pure water and 50 g of methanol were added. 10 g of tetraethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-04, SiO2 equivalent solid content concentration 29% by mass) and 2 g of methyltriethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-13, condensation reaction product equivalent solid content 38% by mass) were slowly added as inorganic binder components, and the mixture was stirred at 24°C for 5 hours. Subsequently, 0.05 g of bis(4-hydroxyphenyl) sulfide (Tokyo Chemical Industries Co., Ltd.) was added as a stabilizer, and 0.01 g of acetylene-based surfactant (Nisshin Chemical Industry Co., Ltd., Surfinol 420) was added as a surface modifier. The mixture was stirred for another hour to obtain conductive paint BC1. The binder content of conductive paint BC1 is 76.3 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0101] [Conductive paint BC2] To 10 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2, 10 g of aqueous dispersion polyester resin (manufactured by Takamatsu Oil & Fat Co., Ltd., PESRESIN A645GH, solid content concentration 30% by mass) as an organic binder component, 5 g of ethylene glycol with a boiling point of 197°C, 40 g of pure water, and 35 g of methanol were added and stirred at 24°C for 1 hour. Subsequently, 0.1 g of gallic acid as a stabilizer and 0.01 g of acetylene-based surfactant (manufactured by Nisshin Chemical Industry Co., Ltd., Dynol 604) as a surface modifier were added and stirred for another hour to obtain conductive paint BC2. The binder content of conductive paint BC2 is 25.0 times by weight compared to the content of the conductive composite (PEDOT-PSS).

[0102] [Conductive polymer-free paint C1] 39 g of pure water was mixed with 50 g of methanol, and 10 g of tetraethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-04, SiO2 equivalent solid content concentration 29% by mass) and 2 g of methyltriethoxysilane (Shin-Etsu Chemical Co., Ltd., KBE-13, condensation reaction product equivalent solid content 38% by mass) were slowly added as inorganic binder components. The mixture was stirred at 24°C for 5 hours. Subsequently, 0.05 g of bis(4-hydroxyphenyl) sulfide (Tokyo Chemical Industries Co., Ltd.) was added as a stabilizer, and 0.01 g of acetylene-based surfactant (Nisshin Chemical Industry Co., Ltd., Surfinol 420) was added as a surface modifier. The mixture was stirred for another hour to obtain paint C1 that does not contain conductive polymers.

[0103] The following materials were used as the base material. PET: Polyethylene terephthalate film (manufactured by Toray Industries, Ltd., Lumirror T60) PC: Polycarbonate film (Teijin Corporation, Panlight PC-1151) PMMA: Acrylic resin sheet (manufactured by Mitsubishi Chemical Corporation, Acrylite)

[0104] (Example 1) Conductive coating A1 was applied to a PET substrate using a bar coater (wet film thickness 16 μm), and heated and dried at a drying temperature of 100°C for 5 minutes to form conductive layer A1. Conductive coating B1 was then applied to this film using the same bar coater (wet film thickness 16 μm), and heated and dried at a drying temperature of 100°C for 15 minutes to create a conductive laminate in which conductive layer B1 was laminated on conductive layer A1. The obtained conductive laminate was evaluated using the following method. The evaluation results are summarized in Table 1. For comparison, conductive layer A1 and conductive layer B1 were also formed individually on the substrate using the same method, and their surface resistance values ​​were evaluated.

[0105] [Surface resistance value] The surface resistance was measured using a resistivity meter (Loresta-GX manufactured by Nitto Seikou Analytech Co., Ltd., or Hiresta-UX manufactured by Nitto Seikou Analytech Co., Ltd.) under the condition of an applied voltage of 10V. The surface resistance (R) of the conductive laminate in Example 1 C The surface resistance (R) of the conductive layer A1 alone was 650 Ω / sq. A) is 600Ω / sq., and the surface resistance value (R) of the conductive layer B1 only is 600Ω / sq. B The ratio of surface resistance (R) was 30kΩ / sq. C / R A The value was 1.08.

[0106] [Coating adhesion] The adhesion of the coating film on the conductive laminate was evaluated according to the test method specified in JIS K5600-5-6:1999 (cross-cut method). A grid pattern of cuts was made from the surface of conductive layer B of the conductive laminate to the underlying conductive layer A using a dedicated jig, and the adhesion was evaluated using a 25 mm wide transparent pressure-sensitive adhesive tape. The evaluation criteria are shown below. The adhesion evaluation result for the conductive laminate in Example 1 was A. Rating A: The edges of the cuts are perfectly smooth, and there is no peeling in any of the grid lines. Rating B: Less than 5% of the grid in the cross-cut section has peeling. Rating C: In the cross-cut sections, the percentage of grids with peeling is between 5% and 35%. Rating D: In the cross-cut sections, more than 35% of the grid has peeling.

[0107] [Solvent resistant] The solvent resistance of conductive layer B exposed on the surface of the conductive laminate was evaluated by the method described below. 200 μL of acetone was dropped onto the surface of conductive layer B using a lightweight pipette, left for 1 minute, and then wiped off with a nonwoven cloth. The appearance of the test area was then visually observed and evaluated. The evaluation criteria are shown below. The solvent resistance evaluation result for Example 1 was A. Evaluation A: No change in the appearance of the test area. Evaluation B: Cloudiness is observed in the test area. Evaluation C: Peeling of the coating is observed in the test area.

[0108] (Examples 2-6, Comparative Examples 1-4) A conductive laminate was prepared and evaluated using the same method as in Example 1, except that the substrate and conductive paint were changed. The paints used and the evaluation results are summarized in Table 1. For the sake of readability, "RA" has been written as "RA", "RB" as "RB", and "RC" as "RC".

[0109] [Table 1]

[0110] The overall surface resistance of the conductive laminates in Examples 1 to 6 of the present invention was equivalent to that of a single conductive layer A, despite the presence of a conductive layer B with a high surface resistance on its own. Furthermore, they exhibited strong adhesion to the substrate and high solvent resistance. In addition, the hardness of conductive layer B was also high due to the influence of alkoxysilane condensates contained in conductive layer B. On the other hand, the surface resistance of the conductive laminate in Comparative Example 1, in which conductive layer B does not contain a conductive polymer, is high. Also, in Comparative Example 2, conductive layer B formed with paint BC1 that does not contain a high boiling point solvent has a lower content of conductive composite and a relatively higher content of binder compared to the other examples, so the surface resistance of the conductive laminate in Comparative Example 2 is high. The results for Comparative Example 2 are particularly significant. It is understood that even if the surface resistance of conductive layer A alone is low, if the surface resistance of conductive layer B alone is 100 MΩ / sq. or higher, the overall surface resistance of the conductive laminate cannot be sufficiently reduced. Furthermore, Comparative Example 3, in which conductive layer A did not contain an organic binder, had poor adhesion to the substrate, and Comparative Example 4, in which conductive layer B did not contain an inorganic binder, had poor solvent resistance.

Claims

1. A substrate, and a conductive layer A laminated on at least a portion of the surface of the substrate, A conductive laminate comprising a conductive layer B laminated on the surface of the conductive layer A, The conductive layer A comprises a conductive polymer and an organic binder. The conductive layer B comprises a conductive polymer and an inorganic binder. The surface resistance of the conductive layer B alone is less than 100 MΩ / sq. The surface resistance value R A of the conductive layer A alone is lower than the surface resistance value R B of the conductive layer B alone, and is between 100 and 10,000 Ω / sq. The ratio (RC / RA) of the total surface resistance R C of the conductive laminate to the surface resistance R A of the conductive layer A alone is between 1.0 and 2.

0. The conductive polymer contained in conductive layer A and conductive layer B is a π-conjugated conductive polymer, the π-conjugated conductive polymer is polystyrene sulfonic acid-doped poly(3,4-ethylenedioxythiophene) formed by creating a conductive composite with a sulfonic acid group-containing polymer, and the conductive composite is water-dispersible. The aforementioned organic binder contains polyester resin, The inorganic binder comprises an alkoxysilane condensate, In the conductive layer A, the content of the organic binder is 1 to 10 times by mass relative to the content of the conductive composite. A conductive laminate in which the content of the inorganic binder in the conductive layer B is 10 to 60 times by mass compared to the content of the conductive composite.

2. The conductive laminate according to Claim 1, wherein the content of polystyrene sulfonic acid in the conductive composite is 100 parts by mass or more and 500 parts by mass or less per 100 parts by mass of poly(3,4-ethylenedioxythiophene).

3. The conductive laminate according to claim 1, wherein the substrate is a synthetic resin.

4. The conductive laminate according to claim 1, wherein the average thickness of the conductive layer A is 10 nm or more and 10 μm or less.

5. The conductive laminate according to claim 1, wherein the average thickness of the conductive layer B is 10 nm or more and 10 μm or less.

6. The conductive laminate according to claim 1, wherein the surface resistance of the conductive layer B alone is less than 1 MΩ / sq.

7. The conductive laminate according to claim 1, wherein the inorganic binder comprises a condensate of an alkoxysilane having an alkoxy group having 1 to 3 carbon atoms.

8. A method for manufacturing a conductive laminate according to any one of claims 1 to 7, The process involves applying a coating A containing the conductive polymer, the organic binder, and the dispersion medium to at least a portion of the surface of the substrate, and drying the coating film to form the conductive layer A. The process involves applying a paint B containing the conductive polymer, the inorganic binder, and the dispersion medium to the surface of the conductive layer A, and drying the paint film to form the conductive layer B. Includes, The aforementioned paint A contains a high-boiling-point solvent with a boiling point of 150°C or higher at 1 atmosphere. The content of the high-boiling point solvent relative to the total mass of the paint A is 1% by mass or more. A method for manufacturing conductive laminates.

9. The paint B contains water as the dispersion medium, and the water content relative to the total mass of the paint B is 30% by mass or more. A method for manufacturing a conductive laminate according to claim 8, wherein the inorganic binder in the coating film is cured by heating the coating film obtained by applying the paint B.

10. The method for manufacturing a conductive laminate according to claim 9, wherein at least one of the paint A and the paint B contains a surfactant.

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