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

Abstract

To provide a conductive polymer dispersion with improved storage stability. [Solution] A conductive polymer dispersion comprising a conductive composite containing a π-conjugated conductive polymer and a polyanion, and a dispersion medium, wherein the Fe content relative to the total mass of the conductive polymer dispersion is 0.08 ppm or less. The ratio expressed as Fe content / S content in the conductive polymer dispersion is 1.5 × 10 -4 The following is preferable: It is preferable that the anionic group that does not participate in doping the polyanion is modified by reaction with at least one selected from epoxy compounds, amine compounds, and quaternary ammonium compounds.

Description

Technical Field

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

Background Art

[0002] Conjugated conductive polymers form conductive composites by doping with polyanions having anionic groups, resulting in dispersibility in water. Furthermore, by reacting anionic groups not involved in the doping of polyanions with amine compounds or quaternary ammonium compounds and chemically modifying them, dispersibility in organic solvents can be imparted. By coating a substrate with these dispersions of conductive composites (conductive polymer dispersions), conductive films, capacitors, etc. provided with a conductive layer can be produced.

[0003] When a storage period of about 30 days elapses after the production of the conductive polymer dispersion, the properties of the conductive layer formed from the coating film of the conductive polymer dispersion may change. Examples of this change include an increase in surface resistance value and a decrease in atmospheric exposure resistance. Patent Document 1 discloses a method for improving the storage stability of a conductive polymer dispersion by reducing the oxygen concentration in the storage container of the conductive polymer dispersion.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The inventors of the present invention have intensively studied a new method for improving the storage stability of a conductive polymer dispersion, found that the Fe (iron atom) content in the conductive polymer dispersion is an important factor, and completed the present invention.

[0006] This invention provides a conductive polymer dispersion with improved storage stability. [Means for solving the problem]

[0007] [1] A conductive polymer dispersion comprising a conductive composite containing a π-conjugated conductive polymer and a polyanion, and a dispersion medium, wherein the Fe content of the conductive polymer dispersion is 0.08 ppm or less relative to the total mass of the conductive polymer dispersion. [2] The conductive polymer dispersion according to [1], wherein the π-conjugated conductive polymer comprises a polythiophene-based conductive polymer. [3] The conductive polymer dispersion according to [1] or [2], comprising the polyanion polystyrene sulfonic acid. [4] The ratio expressed as Fe content / S content in the conductive polymer dispersion is 1.5 × 10 -4 A conductive polymer dispersion as described in any of the following [1] to [3]. [5] A conductive polymer dispersion according to any one of [1] to [4], wherein an anionic group not involved in the doping of the polyanion is modified by reaction with at least one selected from epoxy compounds, amine compounds and quaternary ammonium compounds. [6] A conductive polymer dispersion according to any one of [1] to [5], comprising an organic solvent as the dispersion medium. [7] The conductive polymer dispersion according to any one of [1] to [6], wherein the dispersion medium is methyl ethyl ketone. [8] A conductive polymer dispersion according to any of [1] to [7], which has been manufactured more than one month ago. [9] A method for producing a conductive polymer dispersion, comprising: a reaction step of mixing a dispersion in which a conductive composite containing a π-conjugated conductive polymer and a polyanion is dispersed in an aqueous dispersion medium with a solution in which at least one selected from epoxy compounds, amine compounds and quaternary ammonium compounds is dissolved in a solvent to obtain a reaction solution to obtain a reaction product produced in the reaction solution; and a dispersion step of mixing the reaction product with a dispersion medium to disperse the reaction product to obtain a conductive polymer dispersion, wherein in the reaction step, the reaction solution is placed in a container made of SUS-316 to produce the reaction product, and the Fe content relative to the total mass of the conductive polymer dispersion in the dispersion step is 0.08 ppm or less.

[10] A conductive laminate comprising a substrate and a conductive layer formed on at least a portion of the surface of the substrate, wherein the conductive layer is a cured product of a conductive polymer dispersion described in any of [1] to [8]. [Effects of the Invention]

[0008] The conductive polymer dispersion of the present invention has improved storage stability and can form a conductive layer with excellent conductivity. According to the method for producing a conductive polymer dispersion of the present invention, a conductive polymer dispersion with improved storage stability can be easily produced.

[0009] This invention is believed to contribute to SDG Goal 12, "Responsible Consumption and Production."

[0010] 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]

[0011] ≪Conductive polymer dispersion liquid≫ 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, and a dispersion medium. The Fe (iron atom) content of the conductive polymer dispersion is 0.08 ppm or less relative to the total mass. While it is desirable for the Fe content to be zero, it can be difficult to completely eliminate Fe components originating from iron catalysts used during the polymerization of the π-conjugated conductive polymer, reaction vessels used during the production of the conductive polymer dispersion, or iron materials that come into contact with the conductive polymer dispersion or its materials. In this aspect, by setting the Fe content to 0.08 ppm or less, the storage stability of the conductive polymer dispersion can be improved. Therefore, even a conductive polymer dispersion that has been in production for more than one month can exhibit dispersibility comparable to that immediately after production.

[0012] The conductive polymer dispersion in this embodiment may contain sulfur atoms (S). Examples include sulfur atoms derived from polythiophene-based conductive polymers and polystyrene sulfonic acid, which will be described later. The ratio of Fe content to S content in the conductive polymer dispersion in this embodiment is 1.5 × 10⁻⁶ -4 The following is preferable. This is a preferred range derived experimentally.

[0013] <Conductive composite> The conductive composite in 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, conductive composites that are not modified with these excess anionic groups are water-dispersible.

[0014] (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, while from the viewpoint of transparency and conductivity, polythiophene-based conductive polymers are more preferred.

[0015] 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.

[0016] (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, 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 aforementioned polyanions may be used individually or in combination of 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.

[0017] The polyanion content in the conductive composite is preferably 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 amount of anionic groups that do not participate in doping is appropriately suppressed, making it easier to convert the conductive composite to hydrophobic by reacting the anionic groups with, for example, a quaternary ammonium salt.

[0018] When the total number of anionic groups in a polyanion is considered to be 100 mol%, the excess anionic groups are preferably 30 mol% to 90 mol%, and more preferably 45 mol% to 75 mol%.

[0019] (Chemical modification of polyanions) From the viewpoint of improving the dispersibility of the conductive composite in this embodiment in organic solvents, excess anionic groups of the polyanion that do not participate in doping (hereinafter also referred to as "some anionic groups") may be modified by reaction with one or more selected from epoxy compounds, quaternary ammonium compounds, and amine compounds. The following substituent (A) is formed by the reaction of some of the anionic groups of the polyanion with the epoxy compound. The following substituent (B) is formed by the reaction of some anionic groups of the polyanion with an amine compound. The following substituent (C) is formed by the reaction of some anionic groups of the polyanion with a quaternary ammonium compound.

[0020] (Substituent A) The substituent (A) is presumed to be a group represented by the following formula (A1) or the following formula (A2).

[0021] [ka]

[0022] [In formula (A1), R 1 , R 2 , R 3 , and R 4 Each of these is independently a hydrogen atom or any substituent.

[0023] [ka]

[0024] [In equation (A2), m is an integer greater than or equal to 2, and multiple R 5 , multiple R 6 , multiple R7 and a plurality of R 8 are each independently a hydrogen atom or an arbitrary substituent, and the plurality of R 5 may be the same or different, and the plurality of R 6 may be the same or different, and the plurality of R 7 may be the same or different, and the plurality of R 8 may be the same or different.]

[0025] In formulas (A1) and (A2), the bond at the left end indicates that the substituent (A) substitutes for the proton of the anion group. Examples of the anion group having a proton to be substituted include anion groups having an active proton bonded to an oxygen atom such as "-SO3H".

[0026] In formula (A1), examples of any substituent of R 1 , R 2 , R 3 , and R 4 include an aliphatic hydrocarbon group having 1 to 20 carbon atoms that may have a substituent, an aromatic hydrocarbon group having 6 to 20 carbon atoms that may have a substituent, and the like. R 1 and R 3 may combine to form a ring that may have a substituent. For example, R 1 and R 3 are the hydrocarbon groups, and a divalent hydrocarbon group obtained by removing any one hydrogen atom of the monovalent hydrocarbon group of R 1 and a divalent hydrocarbon group obtained by removing any one hydrogen atom of the monovalent hydrocarbon group of R 3 are bonded to each other at the carbon atoms from which the hydrogen atoms have been removed to form a ring. In formula (A2), examples of any substituent of R 5 , R 6 , R 7 , and R 8 include an aliphatic hydrocarbon group having 1 to 20 carbon atoms that may have a substituent, an aromatic hydrocarbon group having 6 to 20 carbon atoms that may have a substituent, and the like. R 5 and R 7It may bond to form a ring which may have substituents. Examples of ring formation are the same as described above. In this specification, "may have substituents" includes both cases where a hydrogen atom (-H) is substituted with a monovalent group and cases where a methylene group (-CH2-) is substituted with a divalent group. Examples of monovalent groups as substituents include C1-C4 alkyl groups, C2-C4 alkenyl groups, halogen atoms (fluorine, chlorine, bromine, iodine, etc.), trialkoxysilyl groups (trimethoxysilyl, etc.), and the like. Examples of divalent groups as substituents include oxygen atoms (-O-), -C(=O)-, and -C(=O)-O-. m is an integer greater than or equal to 2, preferably between 2 and 100, more preferably between 2 and 50, and even more preferably between 2 and 25. When m is above the lower limit, the hydrophobicity of the conductive composite becomes sufficiently high. When m is below the upper limit, it is possible to suppress excessive hydrophobicity or a decrease in conductivity.

[0027] Epoxy compounds are compounds that have one or more epoxy groups in one molecule (epoxy group-containing compounds). In terms of preventing aggregation or gelation, epoxy compounds that have one epoxy group in one molecule are preferred. The epoxy compound that reacts with the conductive composite may be one type or two or more types.

[0028] Examples of monofunctional epoxy compounds having one epoxy group in one molecule include ethylene oxide, propylene oxide, 2,3-butylene oxide, isobutylene oxide, 1,2-butylene oxide, 1,2-epoxyhexane, 1,2-epoxyheptane, 1,2-epoxypentane, 1,2-epoxyoctane, 1,2-epoxydecane, 1,3-butadiene monooxide, 1,2-epoxytetradecane, glycidyl methyl ether, 1,2-epoxyoctadecane, 1,2-epoxyhexadecane, and ethylene oxide. Glycidyl ether, glycidyl isopropyl ether, tert-butyl glycidyl ether, 1,2-epoxyeicosane, 2-(chloromethyl)-1,2-epoxypropane, glycidol, epichlorohydrin, epibromohydrin, butyl glycidyl ether, 1,2-epoxyhexane, 1,2-epoxy-9-decane, 2-(chloromethyl)-1,2-epoxybutane, 2-ethylhexyl glycidyl ether, 1,2-epoxy-1H,1H,2H,2H,3H,3H-trifluorobutane, allyl glycidyl Luether, tetracyanoethylene oxide, glycidyl butyrate, 1,2-epoxycyclooctane, glycidyl methacrylate, 1,2-epoxycyclododecane, 1-methyl-1,2-epoxycyclohexane, 1,2-epoxycyclopentadecane, 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1,2-epoxy-1H,1H,2H,2H,3H,3H-heptadecafluorobutane, 3,4-epoxytetrahydrofuran, glycidyl stearate, 3-glycidyloxypropyl trim Toxysilane, epoxy succinic acid, glycidylphenyl ether, isophorone oxide, α-pinene oxide, 2,3-epoxynorbornene, benzyl glycidyl ether, diethoxy(3-glycidyloxypropyl)methylsilane, 3-[2-(perfluorohexyl)ethoxy]-1,2-epoxypropane, 1,1,1,3,5,5,5-heptamethyl-3-(3-glycidyloxypropyl)trisiloxane, 9,10-epoxy-1,5-cyclododecadiene, 4-tert-butylbenzoate glycidyl, 2,2-Bis(4-glycidyloxyphenyl)propane, 2-tert-butyl-2-[2-(4-chlorophenyl)]ethyloxirane, styrene oxide, glycidyl trityl ether, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-phenylpropylene oxide, cholesterol-5α,6α-epoxide, stilbene oxide, p-glycidyl p-toluenesulfonate, ethyl 3-methyl-3-phenylglycidate, N-propyl-N-(2,3-epoxypropyl)perfluoro-n- Examples include octyl sulfonamide, (2S,3S)-1,2-epoxy-3-(tert-butoxycarbonylamino)-4-phenylbutane, 3-nitrobenzenesulfonic acid (R)-glycidyl, 3-nitrobenzenesulfonic acid-glycidyl, parthenolide, N-glycidylphthalimide, endrin, dieldrin, 4-glycidyloxycarbazole, 7,7-dimethyloctanoic acid [oxyranylmethyl], 1,2-epoxy-4-vinylcyclohexane, and higher alcohol glycidyl ethers having 10 to 16 carbon atoms.

[0029] The aforementioned higher alcohol glycidyl ether is preferably one or more higher alcohol glycidyl ethers having 10 to 16 carbon atoms, more preferably one or more higher alcohol glycidyl ethers having 12 to 14 carbon atoms, and even more preferably at least one of C12 (12 carbon atoms) higher alcohol glycidyl ethers and C13 (13 carbon atoms) higher alcohol glycidyl ethers.

[0030] Examples of polyfunctional epoxy compounds having two or more epoxy groups in one molecule include 1,6-hexanediol diglycidyl ether, 1,7-octadiene diepoxide, neopentyl glycol diglycidyl ether, 4-butanediol diglycidyl ether, 1,2:3,4-diepoxybutane, 1,2-cyclohexanedicarboxylic acid diglycidyl, isocyanurate triglycidyl, neopentyl glycol diglycidyl ether, 1,2:3,4-diepoxybutane, polyethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, and propylene glycol diglycidyl ether. Examples include ricidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, trimethylolpropane polyglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hexahydrophthalate diglycidyl ester, glycerin polyglycidyl ether, diglycerin polyglycidyl ether, polyglycerin polyglycidyl ether, sorbitol-based polyglycidyl ether, ethylene oxide delauryl alcohol glycidyl ether, and the like.

[0031] Epoxy compounds are preferably 50 to 2000 in molecular weight, as this improves their dispersibility in organic solvents. Furthermore, epoxy compounds are preferably 4 to 120 carbon atoms, more preferably 7 to 100 carbon atoms, even more preferably 10 to 80 carbon atoms, and particularly preferably 15 to 50 carbon atoms, as these improve their dispersibility in low-polarity hydrocarbon solvents and ester solvents.

[0032] (Substituent B) The substituent (B) is presumed to be a group represented by the following formula (B).

[0033] -HN + R 11 R 12 R 13 ...(B) [In formula (B), R 11 ~R 13 Each of these is independently a hydrogen atom or a hydrocarbon group which may have substituents, however R 11 ~R 13 At least one of these is a hydrocarbon group which may have substituents.

[0034] In substituent (B), the leftmost bond indicates that the negative charge of the anionic group is bonded to the positive charge of the amine compound. An example of a negatively charged anionic group is "-SO3 - An example of an anionic group is one in which an active proton is bonded to an oxygen atom.

[0035] R in chemical formula (B) 11 ~R 13 R is a hydrogen atom or a hydrocarbon group which may have substituents. 11 ~R 13 This substituent is derived from the amine compound described later. The hydrocarbon group in chemical formula (B) may be an aliphatic hydrocarbon group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, which may have substituents. Examples of aliphatic hydrocarbon groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl groups. Examples of substituents on aliphatic hydrocarbon groups include phenyl groups and hydroxyl groups. Examples of aromatic hydrocarbon groups include phenyl groups and naphthyl groups. Examples of substituents on aromatic hydrocarbon groups include alkyl groups having 1 to 5 carbon atoms and hydroxyl groups.

[0036] The amine compound is at least one selected from the group consisting of primary amines, secondary amines, and tertiary amines. The amine compound that reacts with the conductive composite may be one type or two or more types. Examples of primary amines include aniline, toluidine, benzylamine, and ethanolamine. Examples of secondary amines include diethanolamine, dimethylamine, diethylamine, dipropylamine, diphenylamine, dibenzylamine, and dinaphthylamine. Examples of tertiary amines include triethanolamine, trimethylamine, triethylamine, tripropylamine, tributylamine, trihexylamine, trioctylamine, triphenylamine, trynzylamine, and trinaphthylamine. Among the amine compounds, tertiary amines are preferred, and at least one of trioctylamine and tributylamine is more preferred, as they can enhance the conductivity of the conductive composite in this embodiment.

[0037] To improve dispersibility in organic solvents, particularly in low-polarity hydrocarbon solvents and ester solvents, amine compounds preferably have substituents with 4 or more carbon atoms on the nitrogen atom, more preferably 6 or more carbon atoms, and even more preferably 8 or more carbon atoms. The upper limit of the carbon number of substituents on the nitrogen atom is not particularly limited, and considering solubility and reactivity in solvents, for example, 50 or less is preferred, 40 or less is more preferred, and 30 or less is even more preferred. Furthermore, the R possessed by the amine compound 11 ~R 13 The total number of carbon atoms is preferably 6 to 33, more preferably 9 to 30, and even more preferably 12 to 27. The number of carbon atoms in each substituent on the nitrogen atom may be the same or different.

[0038] When the conductive composite has substituents (A) and (B), the mass ratio expressed as [substituent (A)]:[substituent (B)] (hereinafter also referred to as the A / B ratio) is preferably 10:90 to 90:10, more preferably 20:80 to 80:20, and even more preferably 25:75 to 75:25. When the A / B ratio is within the above range, it is easier to balance dispersibility and conductivity. The mass of [substituent (A)] can be calculated as [(mass of reactant A obtained by reacting the epoxy compound with the conductive composite) - (mass of the conductive composite before reacting with the epoxy compound)]. The mass of [substituent (B)] can be calculated as [(mass of reactant B obtained by reacting reactant A with the amine compound) - (mass of reactant A)].

[0039] (Substituent C) The substituent (C) is presumed to be a group represented by the following formula (C).

[0040] -N + R 11 R 12 R 13 R 14 ...(C) [In formula (C), R 11 ~R 14 Each of these is independently a hydrocarbon group that may have substituents.

[0041] In substituent (C), the leftmost bond indicates that the negative charge of the anionic group is bonded to the positive charge of the quaternary ammonium cation. An example of a negatively charged anionic group is "-SO3 - An example of an anionic group is one in which an active proton is bonded to an oxygen atom.

[0042] R in chemical formula (C) 11 ~R 14 R is a hydrocarbon group which may have substituents. 11 ~R 14 This substituent is derived from a quaternary ammonium compound. The hydrocarbon group in chemical formula (C) may be an aliphatic hydrocarbon group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, which may have substituents. Examples of aliphatic hydrocarbon groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl groups. Examples of substituents on aliphatic hydrocarbon groups include phenyl groups and hydroxyl groups. Examples of aromatic hydrocarbon groups include phenyl groups and naphthyl groups. Examples of substituents on aromatic hydrocarbon groups include alkyl groups having 1 to 5 carbon atoms and hydroxyl groups.

[0043] Because dispersibility in organic solvents is improved and conductivity is enhanced, quaternary ammonium compounds preferably have substituents with 3 or more carbon atoms on the nitrogen atom, more preferably have substituents with 5 or more carbon atoms, and even more preferably have substituents with 7 or more carbon atoms on the nitrogen atom. The upper limit of the number of carbon atoms of each substituent on the nitrogen atom is not particularly limited, and considering solubility and reactivity in solvents, for example, 40 or less is preferred, 30 or less is more preferred, and 20 or less is even preferred. Furthermore, the R possessed by the quaternary ammonium compound 11 ~R 14 The total number of carbon atoms is preferably 8 to 44, more preferably 12 to 40, and even more preferably 16 to 36. The number of carbon atoms in each substituent on the nitrogen atom may be the same or different.

[0044] The quaternary ammonium salt is preferably water-insoluble. Here, water-insoluble means that its solubility in 100g of water at 20°C is less than 1g. Since non-water-soluble quaternary ammonium salts are highly reactive with polyanions in the reaction solution described later, the desired substituent (C) can be easily formed.

[0045] The quaternary ammonium salt is preferably a tetraalkylammonium salt, and more preferably a tetraalkylammonium halide. This is because it has high reactivity with polyanions, and the reaction product is less soluble in aqueous dispersion media and precipitates easily. As the counteranion halogen ion, bromide ions and chloride ions are preferred, and chloride ions are more preferred from the viewpoint of improving conductivity.

[0046] Specific examples of quaternary ammonium compounds include quaternary ammonium salts such as tetramethylammonium salt, tetraethylammonium salt, tetrapropylammonium salt, tetrabutylammonium salt, tetraoctylammonium salt, tetradecylammonium salt, tetraphenylammonium salt, tetrabenzylammonium salt, and tetranaphthylammonium salt. The alkyl groups constituting these quaternary ammonium salts may be linear or branched. Examples of counteranions for ammonium cations include halogen ions such as bromide ions and chloride ions, and hydroxyl ions.

[0047] In polyanions, the mass ratio of [substituent (A)] to [substituent (C)] (hereinafter also referred to as the A / C ratio) is preferably 10:90 to 90:10, more preferably 20:80 to 80:20, and even more preferably 25:75 to 75:25. When the A / C ratio is within the above range, it is easier to balance dispersibility and conductivity. The mass of [substituent (A)] can be calculated as [(mass of reactant A obtained by reacting the epoxy compound with the conductive composite) - (mass of the conductive composite before reacting with the epoxy compound)]. The mass of the [anionic group to which substituent (C) is attached] can be calculated as [(mass of reactant C obtained by reacting reactant A with a quaternary ammonium compound) - (mass of reactant A)].

[0048] The polyanion content in the conductive composite is preferably in the range of 1 to 1000 parts by mass per 100 parts by mass of the π-conjugated conductive polymer, more preferably 10 to 700 parts by mass, and even more preferably 100 to 500 parts by mass. 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 amount of anionic groups that do not participate in doping is appropriately suppressed, and the anionic groups can be easily converted to hydrophobicity when reacting with epoxy compounds and quaternary ammonium compounds or amine compounds.

[0049] The content of the conductive composite relative to the total mass of the conductive polymer dispersion in this embodiment is preferably, for example, 0.01% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 3% by mass or less, and even more preferably 0.2% by mass or more and 1% 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 the conductive polymer dispersion can be further improved. If the value is below the upper limit of the above range, the dispersibility of the conductive composite in the conductive polymer dispersion can be improved, a uniform conductive layer can be formed, and storage stability can be further improved.

[0050] [Dispersion medium] Examples of dispersion media included in the conductive polymer dispersion of this embodiment include water, an organic solvent, and a mixture of water and an organic solvent.

[0051] The dispersion medium contained in the conductive polymer dispersion of this embodiment preferably contains an organic solvent from the viewpoint of improving the dispersibility of the conductive composite. The content of the organic solvent relative to the total mass of the dispersion medium is preferably 70% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, and even more preferably 90% by mass or more and 100% by mass or less.

[0052] <Organic solvents> Examples of the organic solvent include alcohol-based solvents, ether-based solvents, ketone-based solvents, ester-based solvents, hydrocarbon-based solvents, nitrogen atom-containing compound-based solvents, and the like. The organic solvent may be one type or two or more types.

[0053] The aforementioned organic solvent may be a water-soluble organic solvent or a non-water-soluble organic solvent. Here, a water-soluble organic solvent is an organic solvent whose solubility in 100g of water at 20°C is 1g or more, and a non-water-soluble organic solvent is 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.

[0054] 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 and hydrocarbon-based solvents will be described later. Examples of nitrogen atom-containing compound solvents include N-methylpyrrolidone, dimethylacetamide, and dimethylformamide. Examples of solvents not classified as above include dimethyl sulfoxide.

[0055] (Ester-based solvents) Ester solvents are compounds containing ester groups (-C(=O)-O-). When the conductive composite is modified by a reaction between an epoxy compound and an amine compound or a quaternary ammonium compound, it is preferable that the organic solvent includes an ester-based solvent, as this further enhances the dispersibility of the conductive composite. From the viewpoint of improving the dispersibility of the conductive composite, it is preferable to include one or more ester-based solvents represented by the following formula 1z. Formula 1z:R 21 -C(=O)-OR 22 [In the formula, R 21 R represents a hydrogen atom, a methyl group, or an ethyl group. 22 [This represents a linear or branched alkyl group having 1 to 6 carbon atoms.]

[0056] From the perspective of improving the dispersibility of conductive composites, R 21 A methyl group or an ethyl group is preferred, and a methyl group is more preferred. Also, R 22 The number of carbon atoms is preferably 2 to 5, and more preferably 2 to 4.

[0057] Examples of ester solvents include ethyl acetate, propyl acetate, butyl acetate, isopropyl acetate, and isobutyl acetate.

[0058] The content of the ester solvent in the organic solvent is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, even more preferably 70% by mass or more, particularly preferably 80% by mass or more, most preferably 90% by mass or more, and may also be 100% by mass, based on the total mass of the organic solvent. When the content of the ester solvent is within the above range, the dispersibility of the conductive composite can be improved.

[0059] If the conductive polymer dispersion of this embodiment contains an ester-based solvent, it may also contain one or more other organic solvents besides the ester-based solvent. Examples of organic solvents other than ester-based solvents include hydrocarbon-based solvents (described later), ketone-based solvents (mentioned above), alcohol-based solvents, and nitrogen atom-containing compound-based solvents.

[0060] (Hydroxide-based solvents) In the case where the conductive composite contained in the conductive polymer dispersion of this embodiment is modified by reaction with an epoxy compound and an amine compound or a quaternary ammonium compound, the inclusion of a hydrocarbon solvent as a dispersion medium is preferable because it increases the wettability to the plastic film substrate and allows for easy addition of low-polarity binder components.

[0061] Examples of hydrocarbon solvents include aliphatic hydrocarbon solvents and aromatic hydrocarbon solvents. Examples of aliphatic hydrocarbon solvents include pentane, hexane, heptane, octane, decane, cyclohexane, and methylcyclohexane. Examples of aromatic hydrocarbon solvents include benzene, toluene, xylene, ethylbenzene, propylbenzene, and isopropylbenzene. Among these, toluene is preferred because of its high dispersibility of the conductive composite. Furthermore, when a silicone compound is added as a binder component, at least one of heptane and toluene is preferred because of its excellent solubility of the silicone compound.

[0062] It is preferable to include methyl ethyl ketone in addition to the hydrocarbon solvent, as this further improves the dispersibility of the conductive composite. For example, per 100 parts by mass of the hydrocarbon solvent, the amount of methyl ethyl ketone is preferably 20 to 120 parts by mass, more preferably 30 to 100 parts by mass, and even more preferably 40 to 80 parts by mass.

[0063] The hydrocarbon solvent content is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, even more preferably 70% by mass or more, particularly preferably 80% by mass or more, most preferably 90% by mass or more, and may also be 100% by mass, relative to the total mass of the organic solvent. When the hydrocarbon solvent content is within the above range, the dispersibility of the conductive composite can be improved.

[0064] If the conductive polymer dispersion of this embodiment contains a hydrocarbon solvent, it may also contain one or more other organic solvents. Examples of organic solvents other than hydrocarbon solvents include the aforementioned ketone solvents, alcohol solvents, ester solvents, and nitrogen atom-containing compound solvents.

[0065] (High boiling point glycol ethers) From the viewpoint of improving the conductivity of the conductive layer formed from the conductive polymer dispersion of this embodiment, high-boiling point glycol ethers may be included. The following are examples of glycol ether-based organic solvents with a boiling point of 100°C or higher at 1 atmosphere (760 mmHg). The temperature in parentheses is the boiling point. For example, ethylene glycol monomethyl ether (approx. 124°C), diethylene glycol monomethyl ether (approx. 193°C), ethylene glycol monoethyl ether (approx. 136°C), diethylene glycol monoethyl ether (approx. 196°C), ethylene glycol monoethyl ether acetate (approx. 156°C), diethylene glycol monoethyl ether acetate (approx. 217°C), ethylene glycol mono-n-butyl ether (approx. 168°C), diethylene glycol monobutyl ether (approx. 230°C), ethylene glycol monobutyl ether acetate (approx. 192°C), diethylene glycol monobutyl ether acetate (approx. 246°C), propylene glycol monomethyl ether (approx. 121°C) Examples include propylene glycol monomethyl ether acetate (approximately 146°C), dipropylene glycol dimethyl ether (approximately 171°C), propylene glycol monomethyl ether propionate (approximately 161°C), diethylene glycol dimethyl ether (approximately 162°C), triethylene glycol dimethyl ether (approximately 216°C), tetraethylene glycol dimethyl ether (approximately 276°C), ethylene glycol diethyl ether (approximately 121°C), diethylene glycol diethyl ether (approximately 188°C), diethylene glycol methyl ethyl ether (approximately 179°C), diethylene glycol dibutyl ether (approximately 255°C), and diethylene glycol monohexyl ether (approximately 258°C). The high-boiling point glycol ethers contained in the dispersion medium may be one type or two or more types.

[0066] Method for producing conductive polymer dispersions A second aspect of the present invention is a method for producing a conductive polymer dispersion, comprising: a reaction step of obtaining a reaction solution by mixing a dispersion in which a conductive composite containing a π-conjugated conductive polymer and a polyanion is dispersed in an aqueous dispersion medium with a solution in which at least one selected from epoxy compounds, amine compounds, and quaternary ammonium compounds is dissolved in a solvent, thereby obtaining a reaction product generated in the reaction solution; and a dispersion step of mixing the reaction product with a dispersion medium to disperse the reaction product and obtain a conductive polymer dispersion. In this embodiment, the reaction solution can be placed in a container made of SUS-316 during the reaction step to produce the reaction product. In this embodiment, the Fe content relative to the total mass of the conductive polymer dispersion in the dispersion step can be 0.08 ppm or less. According to this embodiment, the conductive polymer dispersion of the first embodiment can be produced.

[0067] The manufacturing method of this embodiment may include a polymerization step to obtain a conductive composite before the reaction step. Furthermore, a washing step may be included between the reaction step and the dispersion step.

[0068] [Polymerization process] The polymerization step is a step of polymerizing monomers that form a π-conjugated conductive polymer in a reaction solution containing a polyanion and a dispersion medium to obtain a conductive polymer dispersion containing a conductive composite containing the π-conjugated conductive polymer and the polyanion, and the dispersion medium. The synthesis of the π-conjugated conductive polymer in the reaction solution can be carried out in the same manner as the conventional synthesis of π-conjugated conductive polymers.

[0069] The dispersion medium constituting the reaction solution is preferably an aqueous dispersion medium containing water. The water content relative to the total mass of the dispersion medium is preferably, for example, 60% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 100% by mass or less, even more preferably 80% by mass or more and 100% by mass or less, and particularly preferably 90% by mass or more and 100% by mass or less. As a dispersion medium other than water, the aforementioned water-soluble organic solvents are preferred.

[0070] The π-conjugated conductive polymer is obtained by chemical oxidative polymerization of the monomer. The chemical oxidation polymerization of the monomer can be carried out in the same manner as known methods. It is preferable to add appropriate amounts of a known catalyst and an oxidizing agent to the reaction solution. Examples of catalysts include transition metal compounds such as ferric chloride, ferric sulfate, ferric nitrate, and cupric chloride. These catalysts can be added in an amount of, for example, 0.01% to 0.05% by mass relative to the total mass of the reaction solution. Examples of oxidizing agents include persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate. Oxidizing agents can restore the reduced catalyst to its original oxidized state. These oxidizing agents can be added in an amount of, for example, 0.1% to 2% by mass relative to the total mass of the reaction solution.

[0071] The polyanion content relative to the total mass of the reaction solution may be the same as the concentration of the polyanion contained in the conductive polymer dispersion to be produced. For example, 0.1% to 10% by mass is preferred, 0.3% to 5% by mass is more preferred, 0.6% to 3% by mass is even more preferred, and 0.9% to 2% by mass is particularly preferred. Within the above range, the π-conjugated conductive polymer to be synthesized can be sufficiently doped with the polyanion, and a conductive composite with excellent conductivity can be synthesized.

[0072] The monomer content relative to the total mass of the reaction solution may be the same as the concentration of the π-conjugated conductive polymer contained in the conductive polymer dispersion to be produced. For example, 0.05% to 2% by mass is preferred, 0.1% to 1.0% by mass is more preferred, 0.2% to 0.8% by mass is even more preferred, and 0.3% to 0.6% by mass is particularly preferred. Within the above range, the π-conjugated conductive polymer to be synthesized can be sufficiently doped with the polyanion, and a conductive composite with excellent conductivity can be synthesized.

[0073] When a catalyst and an oxidizing agent are added to the reaction solution, it is preferable to remove the catalyst and the oxidizing agent from the conductive polymer dispersion. Methods for removal include, for example, contacting a conductive polymer dispersion with an ion exchange resin to adsorb the catalyst and oxidizing agent onto the ion exchange resin, and removing them along with the displacement of the dispersion medium by ultrafiltration of the conductive polymer dispersion. Of these, the method using an ion exchange resin is preferred because it is simple. It is preferable to use a combination of a cation exchange resin and an anion exchange resin.

[0074] [Reaction Process] A reaction product containing the conductive composite is precipitated by adding one or more compounds selected from epoxy compounds, amine compounds, and quaternary ammonium compounds to a conductive polymer dispersion liquid containing an aqueous dispersion medium obtained in the polymerization step. The anionic groups of the conductive composite precipitated in this process react with the added compound to form one of the substituents (A) to (C) mentioned above, thereby making them hydrophobic.

[0075] When one or more epoxy compounds are added to a conductive polymer dispersion, the epoxy groups of the epoxy compounds react with some of the anionic groups of the polyanion. This forms substituent (A), making the conductive composite hydrophobic, which makes stable dispersion in an aqueous dispersion difficult and causes precipitation to occur. When adding epoxy compounds, heating may be performed to accelerate the reaction. The heating temperature is preferably between 40°C and 100°C. The amount of epoxy compound added is preferably 10 parts by mass or more and 10,000 parts by mass or less, more preferably 100 parts by mass or more and 5,000 parts by mass or less, and even more preferably 500 parts by mass or more and 3,000 parts by mass or less, per 100 parts by mass of the conductive composite. When the value is above the lower limit of the above range, the hydrophobicity of the conductive composite becomes sufficiently high, and its dispersibility in organic solvents improves. If the value is below the upper limit of the above range, it is possible to prevent a decrease in conductivity due to unreacted epoxy compounds.

[0076] Before, simultaneously with, or after adding one or more compounds selected from epoxy compounds, amine compounds, and quaternary ammonium compounds to the conductive polymer dispersion, an organic solvent may be added. A water-soluble organic solvent is preferred. Here, a water-soluble organic solvent is defined as an organic solvent with a solubility of 1 g or more per 100 g of water at 20°C. Examples of water-soluble organic solvents include alcohol-based solvents, ketone-based solvents, and ester-based solvents. One or more organic solvents may be added.

[0077] When one or more amine compounds are added to a conductive polymer dispersion, the amine compounds react with some of the anionic groups of the polyanion. This forms substituent (B), making the conductive composite hydrophobic, which makes stable dispersion in an aqueous dispersion difficult and causes precipitation into precipitates. The amount of amine compound added is preferably 1 to 10,000 parts by mass, more preferably 10 to 5,000 parts by mass, and even more preferably 100 to 1,000 parts by mass, per 100 parts by mass of conductive composite. When the value is above the lower limit of the above range, the hydrophobicity of the conductive composite becomes sufficiently high, and its dispersibility in organic solvents improves. If the value is below the upper limit of the above range, the decrease in conductivity due to unreacted amine compounds can be prevented.

[0078] When one or more quaternary ammonium compounds are added to an aqueous dispersion of conductive polymers, the quaternary ammonium compounds react with some of the anionic groups of the polyanion. A substituent (C) is formed, making the conductive complex hydrophobic, which makes stable dispersion in the aqueous dispersion difficult, leading to precipitation and the formation of precipitates. The amount of quaternary ammonium compound added is preferably 1 to 10,000 parts by mass, more preferably 10 to 5,000 parts by mass, and even more preferably 50 to 1,000 parts by mass, per 100 parts by mass of conductive composite. When the value is above the lower limit of the above range, the hydrophobicity of the conductive composite becomes sufficiently high, and its dispersibility in organic solvents improves. If the value is below the upper limit of the above range, it is possible to prevent a decrease in conductivity due to unreacted quaternary ammonium compounds.

[0079] When adding both an epoxy compound and an amine compound or a quaternary ammonium compound to the conductive polymer dispersion, the order of addition is not particularly limited. It is preferable to first add the epoxy compound to react with some of the anionic groups of the polyanion, and then add the amine compound or quaternary ammonium compound to react with the remaining anionic groups of the polyanion, as this facilitates the handling of the synthetic intermediates (reaction intermediates).

[0080] The method for recovering the precipitated reaction product is not particularly limited and can be recovered, for example, by filtration or decantation (solvent replacement).

[0081] The recovered reaction product (precipitation) should preferably contain as little water as possible, and most preferably contain no water at all. However, from a practical standpoint, it may contain water up to 10% by mass or less. Methods for reducing the water content include, for example, washing the precipitate with an organic solvent or drying the precipitate.

[0082] [Washing process] The washing step following the reaction step involves washing the precipitate with an organic solvent for washing. This washing step removes residual water, unreacted epoxy compounds, unreacted amine compounds or quaternary ammonium compounds, and hydrolysates of epoxy compounds. The cleaning organic solvent should preferably be one that can clean while minimizing the dissolution of precipitates. For this reason, alcohol-based solvents are preferred as cleaning organic solvents. The cleaning organic solvent may contain one type of organic solvent or two or more types. There are no particular restrictions on the cleaning method; for example, the precipitate may be washed by pouring a cleaning organic solvent over it, or the precipitate may be washed by stirring it in the cleaning organic solvent.

[0083] [Dispersion process] A solvent is added to the resulting reaction product to obtain a conductive polymer dispersion. The solvent to be added can be any solvent that can disperse the reaction product, and an organic solvent is preferred. The organic solvent can be one of the organic solvents contained in the conductive polymer dispersion of the first embodiment. The method for dispersing the resulting reaction product in a dispersion medium is not particularly limited, and conventional methods for dispersing conductive composites can be applied. For example, a preferred method is to add the reaction product to the aforementioned dispersion medium and disperse it using a high-pressure homogenizer.

[0084] <<Conductive Laminate>> A third aspect of the present invention is a conductive laminate comprising a substrate and a conductive layer formed on at least a portion of the substrate, the conductive layer being a cured layer of a conductive polymer dispersion according to the first aspect.

[0085] [Conductive layer] The area in which the conductive 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 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 layer is formed on only a part of the surface of the substrate, for example, the conductive layer may be a fine conductive pattern such as a circuit or an electrode, or the area with the conductive layer and the area without the conductive layer may exist on the same surface and be roughly separated.

[0086] The average thickness of the conductive layer is preferably, for example, 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 layer is above the lower limit, high conductivity can be achieved, and if it is below the upper limit, the adhesion of the conductive layer to the substrate is further improved. The average thickness of the conductive layer is the average of the measurements taken at 10 randomly selected locations.

[0087] [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.

[0088] (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 a polyester resin, and among these, polyethylene terephthalate is preferred.

[0089] 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 layer.

[0090] 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.

[0091] (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 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.

[0092] The average thickness of the glass substrate is preferably 100 μm to 3000 μm, and more preferably 100 μm to 1000 μm. 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.

[0093] ≪Method for manufacturing conductive laminates≫ A fourth aspect of the present invention is a method for producing a conductive laminate by using the conductive polymer dispersion of the first aspect and performing the following steps 1 to 3 in order. This embodiment makes it possible to manufacture the conductive laminate of the third embodiment.

[0094] (Process 1) This process involves applying the conductive polymer dispersion to at least a portion of the substrate to form a coating film, and then drying the coating film to form a conductive layer, thereby obtaining a conductive laminate.

[0095] The description of the substrate is the same as described above, so any redundant explanation will be omitted here.

[0096] 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.

[0097] There are no particular restrictions on the amount of conductive polymer dispersion applied to the substrate, but considering uniform and even coating, 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.

[0098] The thickness of the coating film immediately after applying the conductive polymer dispersion to the substrate is preferably, for example, 0.1 μm to 500 μm, more preferably 1 μm to 100 μm, and even more preferably 5 μm to 50 μm. The thickness of the coating can be adjusted, for example, by changing the grit size of the bar coater.

[0099] A conductive layer can be formed by drying a coating film of a conductive polymer dispersion applied to a substrate, removing at least a portion of the dispersion medium, and then 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, UV irradiation may be performed to cure the binder components contained in the coating film.

[0100] Upon drying of the coating film, a conductive laminate is obtained in which a conductive layer is formed on any surface of the substrate. The average thickness of the conductive layer in the conductive laminate 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 layer is above the lower limit, high conductivity can be achieved, and if it is below the upper limit, the adhesion of the conductive layer to the substrate is further improved. The average thickness of the conductive layer is the average of the measurements taken at 10 randomly selected locations.

[0101] The surface resistance of the conductive layer formed using the initial conductive polymer dispersion immediately after preparation can be, for example, 3500 Ω / □ or less, preferably 3000 Ω / □ or less, more preferably 2000 Ω / □ or less, and even more preferably 1000 Ω / □ or less. The surface resistance of the conductive layer formed using the conductive polymer dispersion after preparation and storage at 40°C for one month can be, for example, 3500 Ω / □ or less, preferably 3000 Ω / □ or less, more preferably 2000 Ω / □ or less, and even more preferably 1000 Ω / □ or less. There is no particular lower limit to the surface resistance of the conductive layer, but 10Ω / □ is given as a guideline. [Examples]

[0102] (Manufacturing Example 1) Manufacturing of polystyrene sulfonic acid (PSS): Mw120000 220 g of sodium styrene sulfonate was dissolved in 1640 ml of deionized water, and while stirring at 80°C, 17.08 g of sodium peroxodisulfate, which had been previously dissolved in 110 ml of water, was added dropwise over 2 hours, and the solution was stirred for 4 hours. A cation exchange resin was added to the resulting sodium polystyrene sulfonate-containing solution to remove sodium ions. The solid content of the resulting polystyrene sulfonic acid (PSS) aqueous solution 1 was 10% by mass. For PSS aqueous solution 1, the weight-average molecular weight was measured using pullulan manufactured by Showa Denko K.K. as a standard substance, with a GPC (gel permeation chromatography) column and a differential refractive index detector in an HPLC (high-performance liquid chromatography) system. Analysis of the GPC chart, where the vertical axis represents the signal intensity of the differential refractive index and the horizontal axis represents the retention time, revealed that the peak for polystyrene sulfonic acid showed a weight-average molecular weight (Mw) of 120,000.

[0103] (Manufacturing Example 2) Production of PEDOT-PSS aqueous dispersion 57.1 g of 3,4-ethylenedioxythiophene, 1354 g of PSS aqueous solution 1 obtained in Production Example 1, and 7829.73 g of deionized water were mixed. This mixture was kept at 26°C and, while stirring, an oxidation catalyst solution of 11.5 g of ferric sulfate dissolved in 180.3 g of deionized water was added, and 62.5 g of sodium peroxodisulfate dissolved in 505.5 g of deionized water was gradually added dropwise in a constant amount over 2 hours, and the mixture was stirred for a further 4 hours to allow the reaction to proceed. A cation exchange resin (Duolite C255LFH, manufactured by Sumika Chemtex Co., Ltd.) and an anion exchange resin (Duolite A368S, manufactured by Sumika Chemtex Co., Ltd.) were added to the resulting reaction solution to remove the polymerization initiator and iron. This yielded a blue PEDOT-PSS aqueous dispersion with a PEDOT:PSS ratio of 1:2.5 (mass ratio). Its solid content was 1.3% by mass.

[0104] (Example 1) 4.88 g of tetraoctylammonium bromide was dissolved in 450 mL of neoethanol IPM. 200 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 2 was added dropwise to the resulting solution and mixed to precipitate the modified PEDOT-PSS (reaction product). The modified PEDOT-PSS was filtered off, 200 g of isopropyl alcohol was added, and the mixture was stirred for 15 minutes before being filtered again. This washing procedure was repeated to obtain the modified PEDOT-PSS. All of these operations were performed using containers made of SUS-316. The obtained PEDOT-PSS modified product (0.6 g) was mixed with 149 g of methyl ethyl ketone and treated with a high-pressure homogenizer to obtain the desired conductive polymer dispersion.

[0105] (Comparative Example 1) A PEDOT-PSS modified product was obtained in the same manner as in Example 1, except that the procedure in Example 1 was performed in a container made of SUS-304.

[0106] (Example 2) A PEDOT-PSS modified product was obtained in the same manner as in Example 1, except that the procedure in Example 1 was performed in a glass container.

[0107] Neoethanol IPM is a mixed solvent consisting of 85% by mass of ethanol, 1% by mass of methanol, and 14% by mass of isopropyl alcohol. SUS-316 is an austenitic stainless steel with added molybdenum. SUS-304 is an austenitic stainless steel.

[0108] <Rating> [Ion concentration] The conductive polymer dispersions obtained in each example were transferred to glass dishes washed with dilute nitric acid, and the solvent was evaporated to dryness on a 70°C hot plate. 0.1 g of the solid remaining in the glass dish was taken and acid-decomposed with 10 mL of nitric acid using a microwave decomposition apparatus, and the volume was adjusted to 50 mL. The samples were quantified by ICP-OES. The following apparatus was used for this procedure. • CEM's MARS6 microwave sample decomposition system • Agilent Technologies Plasma Atomic Energy Spectrometer Agilent ICP-OES 5800 The measurement results are shown in Table 1. In the table, 1.5E-04 is 1.5 × 10⁻⁶. -4 This represents the values, and the same applies to the others. Furthermore, "in solid matter" refers to the measured concentrations of iron and sulfur contained in the dried solid sample, while "in stock solution" refers to the iron and sulfur content relative to the total mass of the conductive polymer dispersion, calculated inversely from the measured values.

[0109] [Storage stability] The conductive polymer dispersion obtained in each example was applied to a polyester film (Toray Industries, Inc., Lumirror T60) using a bar coater No. 8, and dried at 120°C for 2 minutes to obtain a conductive film. The surface resistance R0 of the fabricated conductive film was measured using a resistivity meter (Mitsubishi Chemical Analytec, Inc., Hi-Resta) with an applied voltage of 10V (unit: Ω / □: ohms per square). A smaller surface resistance indicates higher conductivity. The measurement results are shown in Table 1 as "initial".

[0110] Next, the conductive polymer dispersions obtained in each example were placed in sealed bottles and stored in a constant temperature bath at 40°C for one month. Afterward, conductive films were prepared using the stored conductive polymer dispersions in the same manner as described above, and their surface resistance R1 was measured. The measurement results are shown in Table 1 as "after one month".

[0111] [Table 1]

[0112] The dispersibility of conductive composites in conductive polymer dispersions correlates with the surface resistance of the formed conductive layer. The conductive polymer dispersion according to the present invention has an iron concentration of 0.08 ppm or less, resulting in excellent initial dispersibility and post-storage dispersibility of the PEDOT-PSS modified material.

Claims

1. A conductive polymer dispersion comprising a conductive composite containing a π-conjugated conductive polymer and a polyanion, and a dispersion medium, wherein the Fe content of the conductive polymer dispersion is 0.08 ppm or less relative to the total mass of the conductive polymer dispersion.

2. The conductive polymer dispersion according to claim 1, wherein the π-conjugated conductive polymer comprises a polythiophene-based conductive polymer.

3. The conductive polymer dispersion according to claim 2, wherein the polyanion contains polystyrene sulfonic acid.

4. The ratio expressed as Fe content / S content in the conductive polymer dispersion is 1.5 × 10 －４ The conductive polymer dispersion according to claim 3, which is as follows:

5. The conductive polymer dispersion according to claim 4, wherein an anionic group not involved in the doping of the polyanion is modified by reaction with at least one selected from epoxy compounds, amine compounds, and quaternary ammonium compounds.

6. The conductive polymer dispersion according to claim 5, wherein the dispersion medium contains an organic solvent.

7. The conductive polymer dispersion according to claim 6, wherein the dispersion medium is methyl ethyl ketone.

8. A conductive polymer dispersion according to claim 6, which has been manufactured more than one month ago.

9. A reaction step to obtain a reaction solution by mixing a dispersion in which a conductive composite containing a π-conjugated conductive polymer and a polyanion is dispersed in an aqueous dispersion medium with a solution in which at least one selected from epoxy compounds, amine compounds, and quaternary ammonium compounds is dissolved in a solvent, and to obtain a reaction product generated in the reaction solution, A method for producing a conductive polymer dispersion, comprising a dispersion step of mixing the reaction product with a dispersion medium to disperse the reaction product and obtain a conductive polymer dispersion, In the reaction step, the reaction solution is placed in a container made of SUS-316 to produce the reaction product. A method for producing a conductive polymer dispersion, wherein the Fe content relative to the total mass of the conductive polymer dispersion in the dispersion step is 0.08 ppm or less.

10. The system comprises a base material and a conductive layer formed on at least a portion of the surface of the base material, A conductive laminate wherein the conductive layer is a cured product of a conductive polymer dispersion according to any one of claims 1 to 8.

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