JP7269844B2 - Method for producing highly conductive composite, method for producing organic solvent dispersion of highly conductive composite, method for producing conductive film - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a highly conductive composite, a method for producing an organic solvent dispersion of a highly conductive composite, a conductive film, and a method for producing the same.

A conductive polymer dispersion containing a conductive composite of poly(3,4-ethylenedioxythiophene) doped with polystyrenesulfonic acid may be used as a paint for forming a conductive layer.
Patent Document 1 discloses a method of adding an epoxy compound to an anion group of the conductive composite to make the conductive composite hydrophobic in order to improve the dispersibility of the conductive composite in an organic solvent. there is

JP 2019-8912 A

However, when producing a hydrophobized conductive composite by the method of Patent Document 1, the desired reaction product produced in water may be fractionated by filtration. However, the time required for this filtration treatment is very long, and there is a problem of clogging of the filter paper, and improvement in production efficiency has been demanded.
The present invention provides a method for producing a highly conductive composite with excellent production efficiency, a method for producing an organic solvent dispersion of a highly conductive composite, a conductive film, and a method for producing the same.

[1] Obtaining a mixed liquid obtained by mixing an aqueous dispersion of a conductive composite containing a π-conjugated conductive polymer and a polyanion with an organic solvent, and precipitating a highly conductive composite in the mixed liquid. and adding an epoxy compound to the mixed solution to fractionate the highly conductive composite to which the epoxy compound is added.
[2] The method for producing a highly conductive composite according to [1], wherein the content of the organic solvent contained in the mixed liquid is 50% by mass or more with respect to the total mass of the mixed liquid.
[3] The method for producing a highly conductive composite according to [1] or [2], wherein the organic solvent contains at least one of a ketone solvent and an alcohol solvent.
[4] The method for producing a highly conductive composite according to [3], wherein the organic solvent contains a ketone solvent, and the ketone solvent contains methyl ethyl ketone.
[5] The method for producing a highly conductive composite according to [3], wherein the organic solvent contains an alcohol solvent, and the alcohol solvent contains methanol.
[6] The method for producing a highly conductive composite according to [1] or [2], wherein the organic solvent contains methyl ethyl ketone and methanol.
[7] The highly conductive composite according to any one of [1] to [6], wherein the mixed liquid is heated to 40 ° C. or higher when depositing the highly conductive composite in the mixed liquid. Production method.
[8] When depositing the highly conductive composite in the mixed liquid, the content of at least one of an acid and a base other than the polyanion in the mixed liquid is 0 with respect to the total mass of the mixed liquid. .1 mass % or less, the method for producing a highly conductive composite according to any one of [1] to [7].
[9] The method for producing a highly conductive composite according to any one of [1] to [8], wherein the method for separating the highly conductive composite to which the epoxy compound is added is filtration.
[10] The method for producing a highly conductive composite according to any one of [1] to [9], wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene).
[11] The method for producing a highly conductive composite according to any one of [1] to [10], wherein the polyanion is polystyrenesulfonic acid.
[12] An organic solvent dispersion of a highly conductive composite, comprising mixing the highly conductive composite obtained by the production method according to any one of [1] to [11] with an organic solvent. manufacturing method.
[13] A method for producing an organic solvent dispersion of a highly conductive composite according to [12], further comprising mixing a binder component.
[14] The method for producing an organic solvent dispersion of a highly conductive composite according to [13], wherein the binder component is a compound that forms an acrylic resin after curing.
[15] An organic solvent dispersion of the highly conductive composite obtained by the production method according to any one of [12] to [14] is applied to at least one surface of the film substrate to form A method for producing a conductive film, comprising drying the coated film.
[16] A conductive layer comprising a cured layer of an organic solvent dispersion of the highly conductive composite obtained by the production method according to any one of [12] to [14] on at least one surface of the film substrate. A conductive film with

According to the method for producing a highly conductive composite of the present invention, a highly conductive composite to which an epoxy compound is added can be easily obtained. The resulting highly conductive composite is hydrophobic and can be easily dispersed in organic solvents. By using the highly conductive composite obtained by the present invention, a conductive layer having excellent conductivity can be formed as compared with the case of using a conventional conductive composite.

<<Method for producing highly conductive composite>>
A first aspect of the present invention is to obtain a mixed liquid in which an aqueous dispersion of a conductive composite containing a π-conjugated conductive polymer and a polyanion and an organic solvent is mixed, and to obtain a highly conductive composite in the mixed liquid A method for producing a highly conductive composite, comprising: adding an epoxy compound to the mixed solution after precipitating the body, and separating the highly conductive composite to which the epoxy compound is added. .

[Aqueous dispersion of conductive composite]
The aqueous dispersion of the conductive composite used in this embodiment (hereinafter sometimes referred to as "aqueous conductive polymer dispersion") is a conductive composite containing a π-conjugated conductive polymer and a polyanion, and This aqueous dispersion may contain an organic solvent as long as the conductive composite in the liquid is in a dispersed state.

The polyanion is doped into the π-conjugated conductive polymer to form a conductive composite having conductivity. In the polyanion, only some of the anionic groups are doped into the π-conjugated conductive polymer, and there are surplus anionic groups that do not participate in the doping. Since the surplus anionic groups are hydrophilic groups, the conductive composite has dispersibility in water.

In the conductive polymer aqueous dispersion used in this embodiment, the conductive composite is in a dispersed state. Dispersion state and precipitation state can be easily distinguished visually. The dispersion liquid in the dispersed state has high transparency, and no suspended solid matter is found in the dispersion liquid. On the other hand, the transparency of the precipitated liquid is low, and solid suspended matter is observed in the liquid. Generally, the conductive composite in a dispersed state does not easily precipitate, and even if it is allowed to stand still for 12 hours, precipitation hardly occurs. On the other hand, floating matter in a precipitated liquid tends to settle, and for example, it tends to precipitate when left to stand for about 12 hours.

When the conductive polymer aqueous dispersion used in this embodiment is passed through a filter having a retained particle size of 7 μm, the dispersed conductive composite passes through the filter together with the dispersion medium. On the other hand, the deposited conductive composites can be captured by the filter.
Here, the retained particle size of the filter paper is a measure of the coarseness of the mesh, and is obtained from the leaked particle size when barium sulfate or the like is naturally filtered as specified in JIS P 3801 [filter paper (for chemical analysis)].

(π-conjugated conductive polymer)
The π-conjugated conductive polymer may be any organic polymer having a π-conjugated main chain. molecules, polyphenylene-based conductive polymers, polyphenylene-vinylene-based conductive polymers, polyaniline-based conductive polymers, polyacene-based conductive polymers, polythiophene-vinylene-based conductive polymers, copolymers thereof, and the like. Polypyrrole-based conductive polymers, polythiophenes and polyaniline-based conductive polymers are preferable from the viewpoint of stability in air, and polythiophene-based conductive polymers are more preferable from the viewpoint of transparency.

Polythiophene-based conductive polymers include polythiophene, poly(3-methylthiophene), poly(3-ethylthiophene), poly(3-propylthiophene), poly(3-butylthiophene), and poly(3-hexylthiophene). , poly(3-heptylthiophene), poly(3-octylthiophene), poly(3-decylthiophene), poly(3-dodecylthiophene), poly(3-octadecylthiophene), poly(3-bromothiophene), poly (3-chlorothiophene), poly(3-iodothiophene), poly(3-cyanothiophene), poly(3-phenylthiophene), poly(3,4-dimethylthiophene), poly(3,4-dibutylthiophene) , poly(3-hydroxythiophene), poly(3-methoxythiophene), poly(3-ethoxythiophene), poly(3-butoxythiophene), poly(3-hexyloxythiophene), poly(3-heptyloxythiophene) , poly(3-octyloxythiophene), poly(3-decyloxythiophene), poly(3-dodecyloxythiophene), poly(3-octadecyloxythiophene), poly(3,4-dihydroxythiophene), poly(3 ,4-dimethoxythiophene), poly(3,4-diethoxythiophene), poly(3,4-dipropoxythiophene), poly(3,4-dibutoxythiophene), poly(3,4-dihexyloxythiophene) , poly(3,4-diheptyloxythiophene), poly(3,4-dioctyloxythiophene), poly(3,4-didecyloxythiophene), poly(3,4-didodecyloxythiophene), poly( 3,4-ethylenedioxythiophene), poly(3,4-propylenedioxythiophene), poly(3,4-butylenedioxythiophene), poly(3-methyl-4-methoxythiophene), poly(3- methyl-4-ethoxythiophene), poly(3-carboxythiophene), poly(3-methyl-4-carboxythiophene), poly(3-methyl-4-carboxyethylthiophene), poly(3-methyl-4-carboxy butylthiophene).
Polypyrrole-based conductive polymers include polypyrrole, poly(N-methylpyrrole), poly(3-methylpyrrole), poly(3-ethylpyrrole), poly(3-n-propylpyrrole), poly(3-butyl pyrrole), 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), poly(3-methyl-4-hexyloxypyrrole).
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 from the viewpoint of conductivity, transparency and heat resistance.
The π-conjugated conductive polymer contained in the conductive composite may be of one type or two or more types.

(polyanion)
A polyanion is a polymer having two or more monomer units having an anionic group in its molecule. The anion group of this polyanion functions as a dopant for the π-conjugated conductive polymer and improves the conductivity of the π-conjugated conductive polymer.
The anionic group of the polyanion is preferably a sulfo group or a carboxy group.
Specific examples of such polyanions include polystyrenesulfonic acid, polyvinylsulfonic acid, polyallylsulfonic acid, polyacrylic acid esters having a sulfo group, polymethacrylic acid esters having a sulfo group (e.g., poly(4-sulfobutyl methacrylate) , polysulfoethyl methacrylate, polymethacryloyloxybenzenesulfonic acid), poly(2-acrylamido-2-methylpropanesulfonic acid), polymers having a sulfo group such as polyisoprene sulfonic acid, polyvinyl carboxylic acid, polystyrene carboxylic acid, Polymers having carboxy groups such as polyallylcarboxylic acid, polyacrylic acid, polymethacrylic acid, poly(2-acrylamido-2-methylpropanecarboxylic acid), polyisoprenecarboxylic acid, etc. A polyanion is a single monomer. may be a homopolymer obtained by polymerizing or a copolymer obtained by polymerizing two or more monomers.
Among these polyanions, a polymer having a sulfo group is preferable, and polystyrene sulfonic acid is more preferable, because the conductivity can be further increased.
One of the polyanions may be used alone, or two or more thereof may be used in combination.
The weight average molecular weight of the polyanion is preferably 20,000 or more and 1,000,000 or less, more preferably 100,000 or more and 500,000 or less. The mass-average molecular weight is a mass-based average molecular weight determined by gel permeation chromatography and calculated in terms of polystyrene.

The content of the polyanion in the conductive composite is preferably in the range of 1 part by mass or more and 1000 parts by mass or less with respect to 100 parts by mass of the π-conjugated conductive polymer, and is 10 parts by mass or more and 700 parts by mass or less. and more preferably in the range of 100 parts by mass or more and 500 parts by mass or less. If the polyanion content is at least the above 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 equal to or less than the above upper limit, the π-conjugated conductive polymer can be sufficiently contained, and sufficient conductivity can be ensured.

<Method for Producing Conductive Polymer Aqueous Dispersion>
A conductive polymer aqueous dispersion obtained by dispersing a conductive complex containing a π-conjugated conductive polymer and a polyanion in an aqueous dispersion medium, for example, forms a π-conjugated conductive polymer in an aqueous solution of a polyanion. It can be obtained by chemically oxidatively polymerizing a monomer. A commercially available conductive polymer aqueous dispersion may also be used.

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

The content of the conductive composite contained in the conductive polymer aqueous dispersion of the present embodiment is preferably, for example, 0.1% by mass or more and 20% by mass or less, and 0.1% by mass or more and 0.1% by mass or less, based on the total mass of the aqueous dispersion. 5% by mass or more and 10% by mass or less is preferable, and 1.0% by mass or more and 5.0% by mass or less is more preferable.
If it is at least the lower limit of the above range, deposition of the highly conductive composite becomes easy after the addition of the organic solvent. If it is equal to or less than the upper limit of the above range, the dispersibility of the conductive composite in the aqueous conductive polymer dispersion is enhanced, so that unintended aggregation during storage of the aqueous conductive polymer dispersion is prevented, and the addition of an organic solvent is prevented. The quality of the subsequently deposited highly conductive composite can be made uniform.

The conductive polymer aqueous dispersion used in this embodiment may contain an organic solvent as long as the conductive composite is in a dispersed state. The content of the organic solvent is preferably as small as possible, and more preferably not substantially contained. More preferred are:
As the organic solvent that may be contained in the conductive polymer aqueous dispersion used in this embodiment, one having high miscibility with water is preferable, and examples thereof include alcohol solvents described later.
In this specification, the term "aqueous conductive polymer dispersion" is a term explicitly indicating that it contains water as a dispersion medium and does not substantially contain an organic solvent.

[Preparation of mixed solution]
Methods for obtaining a mixture by mixing an aqueous conductive polymer dispersion with an organic solvent include, for example, a method of adding an organic solvent to an aqueous conductive polymer dispersion, and a method of adding an organic solvent to an aqueous conductive polymer dispersion. The method of adding a liquid, etc. are mentioned. A preferred embodiment includes a method of gradually adding an organic solvent while stirring an aqueous conductive polymer dispersion. With this addition method, it is possible to prevent the organic solvent concentration in the conductive polymer aqueous dispersion from sharply increasing locally, and to gently precipitate the highly conductive composite. A sudden increase in organic solvent concentration can result in heterogeneous agglomerates of highly conductive composites.

The content of the organic solvent contained in the mixed solution is preferably 50% by mass or more and less than 100% by mass, more preferably 55% by mass or more and 90% by mass or less, and 60% by mass with respect to the total mass of the mixed solution. 85% by mass or less is more preferable, and 60% by mass or more and 80% by mass or less is particularly preferable. Here, the content of the organic solvent is the amount including the organic solvent contained in the conductive polymer aqueous dispersion before mixing.
When it is at least the lower limit of the above range, the deposition of the highly conductive composite becomes easier, and the yield of the highly conductive composite is improved.
If it is equal to or less than the upper limit of the above range, the amount of the conductive polymer aqueous dispersion contained in the mixed liquid can be relatively increased, so that the amount of the highly conductive composite to be fractionated can be increased.

The appearance of the mixture obtained by mixing the conductive polymer aqueous dispersion and the organic solvent and allowing the resulting mixture to stand may be such that the water and the organic solvent are completely compatible or separate from each other. However, from the viewpoint of facilitating deposition of the highly conductive composite, it is preferable that they are sufficiently compatible.

(Organic solvent)
A water-soluble organic solvent is preferable as the organic solvent constituting the liquid mixture of this embodiment. Here, the water-soluble organic solvent is an organic solvent that dissolves in an amount of 1 g or more in 100 g of water at a temperature of 20°C.
Examples of water-soluble organic solvents include alcohol-based solvents, ketone-based solvents, and ester-based solvents.
Examples of alcohol solvents include methanol, ethanol, isopropanol, n-butanol, t-butanol, and allyl alcohol.
Examples of ketone solvents include methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, methyl amyl ketone, diethyl ketone, diisopropyl ketone, acetone and diacetone alcohol.
Examples of ester solvents include methyl acetate, ethyl acetate, propyl acetate, and butyl acetate.
An organic solvent may be used individually by 1 type, and may use 2 or more types together.

It is preferable that the organic solvent constituting the liquid mixture of this aspect contains at least one of a ketone solvent and an alcohol solvent.
The ketone-based solvent preferably contains methyl ethyl ketone.
Methanol or isopropanol is preferred as the alcoholic solvent.
When the above suitable organic solvent is included, the highly conductive composite can be deposited more easily in the mixed solution, and the yield can be further improved.

In the liquid mixture of this aspect, methyl ethyl ketone is preferably contained in combination with methanol or isopropanol, and more preferably contained in combination with methanol. In this case, the content of methanol or isopropanol with respect to 100 parts by mass of methyl ethyl ketone is preferably 1 part by mass or more and 100 parts by mass or less, more preferably 3 parts by mass or more and 50 parts by mass or less, and even more preferably 6 parts by mass or more and 20 parts by mass or less. .
When the above suitable combination of organic solvents is included, the highly conductive composite can be deposited more easily in the mixed solution, and the yield can be further improved.
When the organic solvent is included in the above suitable range, the highly conductive composite can be more easily deposited in the mixed liquid, and the yield can be further improved.

In the liquid mixture of this aspect, isopropanol is preferably included in combination with methyl acetate or ethyl acetate. In this case, the content of methyl acetate or ethyl acetate with respect to 100 parts by mass of isopropanol is preferably 10 parts by mass or more and 300 parts by mass or less, more preferably 30 parts by mass or more and 200 parts by mass or less, and 60 parts by mass or more and 100 parts by mass or less. More preferred.
When the above suitable combination of organic solvents is included, the highly conductive composite can be deposited more easily in the mixed solution, and the yield can be further improved.
When the organic solvent is included in the above suitable range, the highly conductive composite can be more easily deposited in the mixed liquid, and the yield can be further improved.

The mixture of this embodiment preferably contains a combination of methyl ethyl ketone, isopropanol, and methyl acetate or ethyl acetate. In this case, the content of methyl acetate or ethyl acetate with respect to 100 parts by mass of isopropanol is preferably 10 parts by mass or more and 300 parts by mass or less, more preferably 30 parts by mass or more and 200 parts by mass or less, and 60 parts by mass or more and 100 parts by mass or less. More preferred. In addition, the content of methyl ethyl ketone with respect to 100 parts by mass of isopropanol is preferably 100 parts by mass or more and 3000 parts by mass or less, more preferably 200 parts by mass or more and 2000 parts by mass or less, and even more preferably 500 parts by mass or more and 1000 parts by mass or less.
When the above suitable combination of organic solvents is included, the highly conductive composite can be deposited more easily in the mixed solution, and the yield can be further improved.
When the organic solvent is included in the above suitable range, the highly conductive composite can be more easily deposited in the mixed liquid, and the yield can be further improved.

When depositing a highly conductive composite in the mixed solution of this aspect, the content of at least one of the acid and the base other than the polyanion in the mixed solution is 0.1 with respect to the total mass of the mixed solution. It is preferably not more than 0.01% by mass, more preferably not more than 0.01% by mass, and most preferably not substantially contained.
Examples of the acid include inorganic acids such as hydrochloric acid and sulfuric acid, and organic acids such as p-toluenesulfonic acid and naphthalenesulfonic acid.
Examples of the base include inorganic bases such as sodium hydroxide and sodium carbonate, and organic bases such as trioctylamine and octylamine.
The above acids and bases can be the cause of inhibiting the precipitation of the highly conductive composite in the mixed solution of this embodiment.

[Precipitation of highly conductive composite]
The method for depositing the highly conductive composite in the prepared mixed solution is not particularly limited, and the mixed solution can be deposited simply by allowing the mixed solution to stand still. In addition, it is not necessary to leave the mixture to stand completely, and the precipitation may be carried out while stirring gently.

When the highly conductive composite is deposited in the mixed liquid, it is preferable to heat the mixed liquid. The heating temperature is preferably 40° C. or higher, more preferably 50° C. or higher and 100° C. or lower, and even more preferably 60° C. or higher and 80° C. or lower. The heating time at the suitable heating temperature can be, for example, 1 hour or more and 10 hours or less.
By heating the mixed solution, the highly conductive composite can be easily deposited in the mixed solution, and the yield of the highly conductive composite can be improved.

[Addition of epoxy compound]
By adding an epoxy compound to the mixed solution in which the above-described highly conductive composite is deposited, the epoxy compound is added to some anion groups of the polyanions constituting the highly conductive composite, thereby forming a highly conductive composite. Can be hydrophobized. The highly conductive composite before hydrophobization has high dispersibility in water, and the hydrophobized high conductivity composite has high dispersibility in organic solvents.
The structure of the substituent in which the epoxy compound is added to the surplus anion group that does not participate in the doping of the polyanion is a substitution represented by the following chemical formula (A1) or the following chemical formula (A2) formed by a ring-opening reaction of the epoxy group. It is believed to be group (A).

［式（Ａ１）中、Ｒ^１１、Ｒ^１２、Ｒ^１３、及びＲ^１４はそれぞれ独立に、水素原子、又は任意の置換基である。］

[In Formula (A1), R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are each independently a hydrogen atom or an arbitrary substituent. ]

［式（Ａ２）中、ｍは２以上の整数であり、複数のＲ^１５、複数のＲ^１６、複数のＲ^１７、及び複数のＲ^１８はそれぞれ独立に、水素原子、又は任意の置換基であり、複数のＲ^１５は同一でも異なっていてもよく、複数のＲ^１６は同一でも異なっていてもよく、複数のＲ^１７は同一でも異なっていてもよく、複数のＲ^１８は同一でも異なっていてもよい。］

[In the formula (A2), m is an integer of 2 or more, and the plurality of R ¹⁵ , the plurality of R ¹⁶ , the plurality of R ¹⁷ , and the plurality of R ¹⁸ are each independently a hydrogen atom or an arbitrary substituent, A plurality of R ¹⁵ may be the same or different, a plurality of R ¹⁶ may be the same or different, a plurality of R ¹⁷ may be the same or different, and a plurality of R ¹⁸ may be the same or different. may ]

In the formulas (A1) and (A2), the leftmost bond represents that the substituent (A) is substituted with the proton of the anion group. An anionic group having a proton to be substituted includes, for example, an anionic group having an active proton bonded to an oxygen atom such as “—SO ₃ H”.

In formula (A1), the optional substituents for R ¹¹ , R ¹² , R ¹³ and R ¹⁴ include an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms and a substituent. Examples include an aromatic hydrocarbon group having 6 to 20 carbon atoms which may be present. R ¹¹ and R ¹³ may combine to form a ring which may have a substituent. For example, R ¹¹ and R ¹³ are the above hydrocarbon groups, and a divalent hydrocarbon group excluding any one hydrogen atom of the monovalent hydrocarbon group of R ¹¹ and a monovalent hydrocarbon of R ¹³ A case where a divalent hydrocarbon group from which any one hydrogen atom is removed from the hydrogen group is combined with the carbon atoms from which the hydrogen atom is removed to form a ring is exemplified.

As used herein, the term “optionally having a substituent” refers to cases in which a hydrogen atom (—H) is substituted with a monovalent group, and cases in which a methylene group (—CH ₂ —) is substituted with a divalent group. Including both when to replace.
Monovalent groups as substituents include alkyl groups having 1 to 4 carbon atoms, alkenyl groups having 2 to 4 carbon atoms, halogen atoms (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), and trialkoxysilyl groups. (trimethoxysilyl group, etc.), and the like.
The divalent group as a substituent includes an oxygen atom (-O-), -C(=O)-, -C(=O)-O- and the like. However, the case where two oxygen atoms are adjacent to each other is excluded.

In formula (A2), the optional substituents for R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ include an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms and a substituent. Examples include an aromatic hydrocarbon group having 6 to 20 carbon atoms which may be present. R15 and R17 may combine to form a ring which may have a substituent. Examples of ring formation are the same as above.

In formula (A2), m is an integer of 2 or more, preferably 2 to 100, more preferably 2 to 50, and even more preferably 2 to 25. When m is at least the above lower limit, the hydrophobicity of the highly conductive composite becomes sufficiently high. When m is equal to or less than the upper limit, it is possible to prevent the hydrophobicity from becoming too high and the conductivity from decreasing.

In this embodiment, the highly conductive composite is in a pre-deposited state in the mixture prior to addition of the epoxy compound. For this reason, the number of carbon atoms in the epoxy compound may be smaller than before.
Conventionally, as disclosed in Patent Document 1, an epoxy compound is added to a conductive composite that is uniformly dispersed in water, and the adduct is precipitated in water. In order to deposit a hydrophilic conductive composite in water, it was necessary to form a substituent (A) having a large number of carbon atoms and a high hydrophobicity. Specifically, a mixed higher alcohol glycidyl ether having 12 and 13 carbon atoms was added to form a substituent (A) having 12 or more carbon atoms. If the number of carbon atoms in the substituent (A) is small, it may not precipitate, or even if it barely precipitates, it often clogs the filter paper during fractionation by filtration, and the fractionation is very troublesome. there were.
On the other hand, in this embodiment, since the highly conductive composite is pre-deposited, it is sufficient to add an epoxy compound having a small number of carbon atoms to neutralize the surplus anionic group charge. From this viewpoint, the number of carbon atoms possessed by the substituent (A) is preferably 1-10, more preferably 2-8, and even more preferably 2-6. When the number of carbon atoms is at least the lower limit of the above range, the highly conductive composite becomes sufficiently hydrophobic, separation from the mixed liquid is facilitated, and the separated highly conductive composite has dispersibility in an organic solvent. improves. When the number of carbon atoms is not more than the upper limit of the above range, the bulkiness of the substituent (A) is reduced, the effect of steric hindrance of the substituent (A) is less likely to occur, and the highly conductive composite exhibits high conductivity. can do.

The molecular weight of the epoxy compound added to the mixed solution is, for example, preferably 50 or more and 1000 or less, more preferably 60 or more and 300 or less, and even more preferably 70 or more and 200 or less.
Within the above range, the preferred substituent (A) described above can be formed.

The epoxy compound is a compound having one or more epoxy groups in one molecule.
An epoxy compound may be used individually by 1 type, and may use 2 or more types together.

Monofunctional epoxy compounds having one epoxy group in one molecule include, for example, 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 monoxide, 1,2-epoxytetradecane, glycidyl methyl ether, 1,2- epoxy octadecane, 1,2-epoxyhexadecane, ethyl 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 ether, 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-glycidyloxypropyltrimethoxysilane, epoxysuccinic 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, glycidyl 4-tert-butylbenzoate, 2,2-bis(4-glycidyloxyphenyl)propane, 2 -tert-butyl-2-[2-(4-chlorophenyl)]ethyloxirane, styrene oxide, glycidyltrityl ether, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-phenylpropylene oxide, cholesterol-5α , 6α-epoxide, stilbene oxide, glycidyl p-toluenesulfonate, ethyl 3-methyl-3-phenylglycidate, N-propyl-N-(2,3-epoxypropyl) perfluoro-n-octylsulfonamide, ( 2S,3S)-1,2-epoxy-3-(tert-butoxycarbonylamino)-4-phenylbutane, (R)-glycidyl 3-nitrobenzenesulfonate, glycidyl 3-nitrobenzenesulfonate, parthenolide, N-glycidyl phthalimide, endrin, dieldrin, 4-glycidyloxycarbazole, 7,7-dimethyloctanoic acid [oxiranylmethyl], 1,2-epoxy-4-vinylcyclohexane, higher alcohol glycidyl ether having 10 to 16 carbon atoms, diallyl mono glycidyl isocyanurate and the like.

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, and 4-butanediol. diglycidyl ether, 1,2:3,4-diepoxybutane, diglycidyl 1,2-cyclohexanedicarboxylate, triglycidyl isocyanurate, neopentyl glycol diglycidyl ether, 1,2:3,4-diepoxybutane, polyethylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, propylene glycol diglycidyl 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, hexahydrophthalic acid diglycidyl ester, glycerin polyglycidyl ether, diglycerin polyglycidyl ether, polyglycerin polyglycidyl ether, sorbitol poly glycidyl ether, ethylene oxide lauryl alcohol glycidyl ether, and the like.

The amount of the epoxy compound added to the mixed solution is 1 part by mass or more and 10000 parts by mass or less with respect to 100 parts by mass of the total mass of the π-conjugated conductive polymer and the polyanion contained in the mixed solution. is preferably 100 to 5,000 parts by mass, more preferably 200 to 1,000 parts by mass, and particularly preferably 300 to 800 parts by mass. If the addition ratio of the epoxy compound is at least the lower limit, the dispersibility of the highly conductive composite in the organic solvent is higher, and if it is at most the upper limit, the conductivity of the highly conductive composite is prevented from decreasing. be able to.

[Preparation of Highly Conductive Complex]
The method of fractionating (recovering) the highly conductive composite to which the epoxy compound is added in the mixed solution is not particularly limited, and examples thereof include filtration, decantation, centrifugation, vacuum drying, freeze drying, and spray drying. etc.
Among them, filtration or decantation is preferable because it is easy to separate components other than the highly conductive composite contained in the mixed liquid from the highly conductive composite. Here, filtration is an operation of trapping the highly conductive composite in a filter through which the mixture has passed. Also, decantation is an operation of precipitating the precipitated highly conductive composite and removing the supernatant.
When fractionating by filtration, it is necessary to deal with clogging of the filter. In addition, since the solid matter of the highly conductive composite is compressed by the filtration pressure on the filter, the highly conductive composite separated by filtration tends to be in a harder state than when separated by decantation. Since the highly conductive composite obtained by decantation is obtained in a relatively soft powder state, it can be easily dispersed in a dispersion medium later.
On the other hand, when separating by decantation, it is necessary to wait until the highly conductive complex precipitates in the mixed liquid. From the viewpoint of increasing the production speed of the highly conductive composite, fractionation by filtration is preferable.

The isolated highly conductive composite is preferably washed with an organic solvent that hardly dissolves the highly conductive composite. Specifically, for example, an organic solvent may be poured over the filter that has captured the highly conductive composite, or an organic solvent may be added to the highly conductive composite remaining at the bottom of the container after decantation and stirred. After that, it may be fractionated again by decantation or the like.
By drying and removing the organic solvent and the like adhering to the isolated highly conductive composite, a dried body of the highly conductive composite can be obtained.

<Effect>
According to the method for producing a highly conductive composite of the present invention, almost all of the conductive composite contained in the mixed liquid is recovered as a deposit of the adduct (reactant) of the highly conductive composite with the epoxy compound. can do. That is, the method for producing a highly conductive composite according to this aspect can exhibit a high yield of 90 to 100% by mass. In addition, it is extremely easy to fractionate the precipitate by filtration. The reason for this is thought to be that the size of the precipitate is larger than that in the conventional method, making it difficult to clog the filter paper.
In the method for producing a highly conductive composite of the present invention, it is speculated that the reason why the highly conductive composite is deposited in the mixed liquid containing the organic solvent is that the highly conductive composite is difficult to dissolve in the organic solvent. be.
Surprisingly, when the precipitated highly conductive composite is used in the production method of the present invention, an epoxy compound is added to a conventional conductive composite (for example, a dispersed conductive composite that has not been precipitated). It is possible to form a conductive layer with excellent conductivity compared to the case of using a hydrophobized conductive composite (obtained by the above method (see Examples and Comparative Examples described later). Even if there is a difference in the chemical composition between the highly conductive composite after deposition and the conventional conductive composite, it is thought that there is a very small amount of organic solvent attached to the highly conductive composite at the molecular level. be done. It is considered that the difference in physicochemical properties affects the difference in conductivity rather than the chemical composition.

<<Method for producing organic solvent dispersion of highly conductive composite>>
A second aspect of the present invention is a method for producing an organic solvent dispersion of a highly conductive composite, comprising mixing the highly conductive composite obtained by the production method of the first aspect and an organic solvent. .
Since the epoxy compound is added to the highly conductive composite obtained in the first mode, it has high dispersibility in organic solvents.

(Organic solvent)
The organic solvent used in the production method of this aspect can be called a dispersion medium or a solvent because it can disperse or dissolve the highly conductive composite. In the present specification, the term "dispersion" may be used without distinguishing between dispersing and dissolving, and the term "dispersion medium" may be used without distinguishing between a dispersion medium and a solvent.
Specific organic solvents include, for example, hydrocarbon-based solvents, ketone-based solvents, alcohol-based solvents, ester-based solvents, nitrogen atom-containing compound-based solvents, and the like. An organic solvent may be used individually by 1 type, and may use 2 or more types together.
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, isopropylbenzene and the like.
Ketone solvents include, for example, diethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, methyl amyl ketone, diisopropyl ketone, methyl ethyl ketone, acetone, diacetone alcohol and the like.
Examples of alcohol solvents include methanol, ethanol, isopropanol, n-butanol, t-butanol, and allyl alcohol.
Examples of ester-based solvents include ethyl acetate, propyl acetate, and butyl acetate.
Examples of nitrogen atom-containing compound solvents include N-methylpyrrolidone, dimethylacetamide, dimethylformamide and the like.

Among the above organic solvents, alcohol-based solvents are preferred in that the wettability of the organic solvent dispersion of the highly conductive composite with respect to the plastic film substrate is increased, and that the relatively highly polar binder component can be easily solubilized. is preferred. Among the alcohol solvents, isopropanol is preferable because the highly conductive composite to which the epoxy compound is added has good dispersibility.

The content of the organic solvent is preferably 50% by mass or more and 99.5% by mass or less, more preferably 70% by mass or more and 99% by mass or less, relative to the total mass of the organic solvent dispersion of the highly conductive composite. When the content of the organic solvent is within the above range, the dispersibility of the highly conductive composite can be enhanced.

In this embodiment, the method of mixing the highly conductive composite and the organic solvent is not particularly limited. When the highly conductive composite is mixed with an organic solvent, the hydrophobized highly conductive composite is easily dispersed. Subsequently, this mixed liquid may be stirred and subjected to further dispersing treatment. The stirring method is not particularly limited, and may be stirring with a weak shearing force such as a stirrer, or may be stirred using a high shearing force disperser (such as a high-pressure homogenizer).

The particle size distribution of the highly conductive composite dispersed in the organic solvent dispersion obtained by the production method of this embodiment is not particularly limited, but is preferably 300 nm or less, more preferably 250 nm or less, and 200 nm or less. is more preferable. Since the highly conductive composite contains a polymer, the lower limit is 1 nm or more as a guide, considering the molecular radius of the polymer.
As the particle size distribution becomes smaller, the conductivity of the conductive layer formed by applying the organic solvent dispersion of the highly conductive composite of the present embodiment can be improved.
Here, the particle size distribution is a value obtained by measuring the cumulant average particle size by a dynamic light scattering method.

The content of the highly conductive composite with respect to the total mass of the organic solvent dispersion of the highly conductive composite of the present embodiment is, for example, preferably 0.01% by mass or more and 10% by mass or less, and 0.1% by mass or more. 5% by mass or less is more preferable, and 0.2% by mass or more and 1.0% by mass or less is even more preferable.
Within the above range, the highly conductive composite can be more stably dispersed.

(binder component)
The organic solvent dispersion of the highly conductive composite of this embodiment may contain a binder component. The binder component is a resin 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 cures when the conductive layer (conductive film) is formed. The thermoplastic resin becomes the binder resin as it is, and the resin formed by curing the curable monomer or oligomer becomes the binder resin.
A binder component may be used individually by 1 type, and may use 2 or more types together.

The curable monomers or oligomers may be thermosetting monomers or oligomers or photocurable monomers or oligomers. Here, an oligomer is a polymer having a mass average molecular weight of less than 10,000.
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 an acrylic monomer or acrylic oligomer is used as the binder component, it can be easily cured by heating or light irradiation.

When curable monomers or oligomers are included, it is preferable to further include a curing catalyst. For example, if it contains a thermosetting monomer or oligomer, it preferably contains a thermal polymerization initiator that generates radicals by heating, and if it contains a photocurable monomer or oligomer, it generates radicals by light irradiation. It preferably contains a photopolymerization initiator that causes the

Specific examples of binder resins derived from binder components include acrylic resins (acrylic compounds), polyester resins, polyurethane resins, polyimide resins, polyether resins, melamine resins, polyacrylamide resins, and silicones.
As the binder resin contained in the organic solvent dispersion of the highly conductive composite of the present embodiment, a compound that forms an acrylic resin after curing and a polyacrylamide resin after curing are used because of their good dispersibility in organic solvents. Compounds are preferred. The acrylic resin preferably contains an acrylic resin having a urethane bond in its molecular structure.

The content of the binder component in the organic solvent dispersion of the highly conductive composite of this embodiment is preferably 100 parts by mass or more and 50000 parts by mass or less, and 1000 parts by mass with respect to 100 parts by mass of the highly conductive composite. It is more preferable that the amount is not less than 20,000 parts by mass and not more than 20,000 parts by mass. When the content of the binder component is at least the above lower limit, the film formability and film strength can be improved when the organic solvent dispersion of the highly conductive composite of the present embodiment is applied to a film substrate. If the content of the binder component is equal to or less than the above upper limit, it is possible to suppress a decrease in conductivity due to a decrease in the content of the highly conductive composite.

(Other additives)
The organic solvent dispersion of the highly conductive composite described above may contain other additives.
Additives are not particularly limited as long as the effects of the present invention can be obtained, and examples thereof include surfactants, inorganic conductive agents, antifoaming agents, coupling agents, antioxidants, and ultraviolet absorbers. However, the additive is anything other than the π-conjugated conductive polymer, the polyanion, the organic solvent, and the binder component.
Examples of surfactants include nonionic, anionic, and cationic surfactants, with nonionic surfactants being preferred from the standpoint of storage stability. A polymeric surfactant such as polyvinylpyrrolidone may also be added.
Examples of inorganic conductive agents include metal ions and conductive carbon. Metal ions can be generated by dissolving a metal salt in water.
Antifoaming agents include silicone resins, polydimethylsiloxane, silicone oils and the like.
Examples of coupling agents include silane coupling agents having a vinyl group or an amino group.
UV absorbers include benzotriazole UV absorbers, benzophenone UV absorbers, salicylate UV absorbers, cyanoacrylate UV absorbers, oxanilide UV absorbers, hindered amine UV absorbers, and benzoate UV absorbers. is mentioned.
When the above-mentioned organic solvent dispersion of the highly conductive composite contains the above-mentioned additive, the content ratio is appropriately determined according to the type of additive. 0.001 parts by mass or more and 5 parts by mass or less.

<Effect>
The highly conductive composite organic solvent dispersion obtained by the production method of the present invention has excellent dispersibility of the highly conductive composite, and the highly conductive composite in the conductive layer formed from the organic solvent dispersion. Excellent dispersibility. Therefore, the conductivity of the conductive layer can be sufficiently enhanced. Furthermore, since the highly conductive composite has good dispersibility, the storage stability of the organic solvent dispersion is also excellent.

≪Method for producing conductive film≫
In the third aspect of the present invention, at least one surface of the film substrate is coated with an organic solvent dispersion of the highly conductive composite obtained by the production method of the second aspect, and the formed coating is dried. A method for producing a conductive film, comprising:

Examples of film substrates used in this embodiment include plastic films.
Examples of film substrate resins constituting plastic films include ethylene-methyl methacrylate copolymer resin, ethylene-vinyl acetate copolymer resin, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinyl alcohol, polyethylene terephthalate, and polybutylene terephthalate. , polyethylene naphthalate, polyacrylate, polycarbonate, polyvinylidene fluoride, polyarylate, styrene elastomer, polyester elastomer, polyethersulfone, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyimide, cellulose triacetate, cellulose acetate propio nate and the like. Among these film substrate resins, polyethylene terephthalate is preferable because it is inexpensive and has excellent mechanical strength.
The film substrate resin may be amorphous or crystalline.
Moreover, the film substrate may be unstretched or stretched.
In addition, the film substrate may be subjected to surface treatment such as corona discharge treatment, plasma treatment, flame treatment, etc., in order to further improve the adhesion of the conductive layer to be formed.

The average thickness of the film substrate is preferably 10 μm or more and 500 μm or less, more preferably 20 μm or more and 200 μm or less. When the average thickness of the film substrate is at least the lower limit, the film is less likely to break, and when it is at most the upper limit, sufficient flexibility as a film can be ensured.
The thickness of a member in this specification is a value obtained by measuring the thickness at arbitrary 10 points and averaging the measured values.

(Coating process)
Examples of methods for applying an organic solvent dispersion of a highly conductive composite to a film substrate include gravure coaters, roll coaters, curtain flow coaters, spin coaters, bar coaters, reverse coaters, kiss coaters, fountain coaters, and rod coaters. , coating methods using coaters such as air doctor coaters, knife coaters, blade coaters, cast coaters, and screen coaters; spraying methods using atomizers such as air spray, airless spray, and rotor dampening; immersion methods such as dipping, etc. can be applied.
Among the above, a bar coater is sometimes used because it can be applied easily. In the bar coater, the coating thickness varies depending on the type. Commercially available bar coaters are numbered for each type, and the larger the number, the thicker the coating.
The coating amount of the dispersion onto the film substrate is not particularly limited, but from the viewpoint of obtaining good conductivity, the solid content should be in the range of 0.1 g/m ² or more and 10.0 g/m ² or less. is preferred.

(Drying process)
Examples of methods for drying the coating film formed on the film substrate include heat drying and vacuum drying. As heat drying, for example, a normal method such as hot air heating or infrared heating can be used. When heat drying is applied, the heating temperature is appropriately set according to the dispersion medium to be used, and can be set to, for example, 50° C. or higher and 150° C. or lower. Here, the heating temperature is the set temperature of the drying device. The drying time for drying at the above temperature can be, for example, 30 seconds or more and 3 minutes or less.
When the coating film contains an active energy ray-curable binder component, it may further include an active energy ray irradiation step of irradiating the dried coating film with an active energy ray. If the active energy ray irradiation step is included, the formation speed of the conductive layer can be increased, and the productivity of the conductive film is improved.
Examples of active energy rays include ultraviolet rays, electron beams, visible rays, and the like. Ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arcs, xenon arcs, metal halide lamps, and the like can be used as the ultraviolet light source.
The illuminance in ultraviolet irradiation is preferably 100 mW/cm ² or more from the viewpoint of sufficiently curing the conductive layer. Moreover, from the viewpoint of sufficiently curing the conductive layer, the integrated amount of light is preferably 50 mJ/cm ² or more. In addition, the illuminance and the integrated amount of light in this specification are measured using Topcon UVR-T1 (industrial UV checker, light receiver; UD-T36, measurement wavelength range: 300 nm or more and 390 nm or less, peak sensitivity wavelength: about 355 nm). It is a measured value.

≪Conductive film≫
A fourth aspect of the present invention is a conductive layer comprising a cured layer of an organic solvent dispersion of a highly conductive composite obtained by the production method of the second aspect on at least one surface of a film substrate. It's a film. The conductive film of this aspect can be produced by the production method of the third aspect.

The conductive film obtained according to this aspect comprises a film substrate and a conductive layer formed on at least one surface of the film substrate. The conductive layer contains the highly conductive composite of the first aspect. An epoxy compound is added to some of the anion groups of the polyanion contained in the conductive layer.
When the applied organic solvent dispersion contains a binder component, the conductive layer contains the binder component or a cured product obtained by curing the binder component.

The average thickness of the conductive layer of the conductive film of this embodiment is, for example, preferably 10 nm or more and 50000 nm or less, more preferably 20 nm or more and 40000 nm or less. If the average thickness of the conductive layer is at least the lower limit, sufficiently high conductivity can be exhibited, and if the average thickness is at most the upper limit, the conductive layer can be easily formed.

The surface resistance value of the conductive layer of the conductive film of the present embodiment is preferably 1×10 ² Ω/□ or more and 1×10 ⁸ Ω/□ or less, and 1×10 ³ Ω/□ as a measure of good conductivity. □ or more and 1×10 ⁷ Ω/□ or less is more preferable, and 1×10 ⁴ Ω/□ or more and 1×10 ⁶ Ω/□ or less is more preferable.

<Effect>
Since the conductive layer of the conductive film of the fourth aspect of the present invention contains a highly conductive composite, it has better conductivity than a conductive layer containing a conventional conductive composite.

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

(Production Example 2) Synthesis of aqueous conductive polymer dispersion 14.2 g of 3,4-ethylenedioxythiophene and 36.7 g of polystyrene sulfonic acid dissolved in 2000 ml of deionized water were mixed at 20°C. let me
The mixed solution thus obtained was kept at 20° C., and while stirring, 29.64 g of ammonium persulfate and 8.0 g of ferric sulfate oxidation catalyst solution dissolved in 200 ml of ion-exchanged water were slowly added, The mixture was stirred for 3 hours to react.
2000 ml of ion-exchanged water was added to the resulting reaction solution, and about 2000 ml of the solvent was removed by ultrafiltration. This operation was repeated three times.
Then, 200 ml of 10 mass % diluted sulfuric acid and 2000 ml of ion-exchanged water were added to the resulting solution, and about 2000 ml of the solvent was removed by ultrafiltration. 2000 ml of ion-exchanged water was added to the residual liquid, and about 2000 ml of the solvent was removed by ultrafiltration. This operation was repeated three times.
Furthermore, 2000 ml of ion-exchanged water was added to the resulting solution, and about 2000 ml of the solvent was removed by ultrafiltration. This operation was repeated five times to obtain a 1.2% polystyrenesulfonic acid-doped poly(3,4-ethylenedioxythiophene) (PEDOT-PSS aqueous dispersion) solution.

(Example 1)
A mixture of 100 g of the PEDOT-PSS aqueous dispersion of Production Example 2 (solid content: 1.2 g), 15.0 g of methanol, and 200 g of methyl ethyl ketone was heated and stirred at 60° C. for 3 hours. Next, the mixed solution was returned to room temperature (20 to 25 ° C.) and left to stand for 1 hour, whereupon the highly conductive composite composed of PEDOT-PSS precipitated in the mixed solution, and the upper layer (supernatant) was formed. turned into a clear liquid.
Next, 5.0 g of 1,2-butylene oxide (hereinafter abbreviated as butylene oxide) was added to the mixed solution and stirred for 1 hour to add butylene oxide to the precipitate of the highly conductive composite. .
Subsequently, 2.3 g of the highly conductive composite to which the epoxy compound was added was obtained by filtration. Fractionation of the highly conductive composite by this filtration treatment was completed in 5 minutes or less.
The filtered highly conductive composite was washed with 100 g of acetone and dried. 472.7 g of isopropanol was added to 2.3 g of this highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

(Example 2)
A mixture of 100 g of the PEDOT-PSS aqueous dispersion of Production Example 2 (solid content: 1.2 g), 15.0 g of methanol, and 200 g of methyl ethyl ketone was heated and stirred at 60° C. for 3 hours. Next, the mixed solution was returned to room temperature (20 to 25 ° C.) and left to stand for 1 hour, whereupon the highly conductive composite composed of PEDOT-PSS precipitated in the mixed solution, and the upper layer (supernatant) was formed. turned into a clear liquid.
Next, 5.0 g of 1,2-epoxy-4-vinylcyclohexane was added to the mixed solution and stirred for 1 hour, and 1,2-epoxy-4-vinylcyclohexane was added to the deposit of the highly conductive composite. let me
Subsequently, 2.5 g of the highly conductive composite to which the above epoxy compound was added was obtained by filtration. Fractionation of the highly conductive composite by this filtration treatment was completed in 5 minutes or less.
The filtered highly conductive composite was washed with 100 g of acetone and dried. 472.5 g of isopropanol was added to 2.5 g of this highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

(Example 3)
A mixture of 100 g of the PEDOT-PSS aqueous dispersion of Production Example 2 (solid content: 1.2 g), 15.0 g of methanol, and 200 g of methyl ethyl ketone was heated and stirred at 60° C. for 3 hours. Next, the mixed solution was returned to room temperature (20 to 25 ° C.) and left to stand for 1 hour, whereupon the highly conductive composite composed of PEDOT-PSS precipitated in the mixed solution, and the upper layer (supernatant) was formed. turned into a clear liquid.
Next, 5.0 g of glycidol was added to the mixed solution and stirred for 1 hour to add glycidol to the deposit of the highly conductive composite.
Subsequently, 2.5 g of the highly conductive composite to which the above epoxy compound was added was obtained by filtration. Fractionation of the highly conductive composite by this filtration treatment was completed in 5 minutes or less.
The filtered highly conductive composite was washed with 100 g of acetone and dried. 472.5 g of isopropanol was added to 2.5 g of this highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

(Example 4)
A mixture of 100 g of the PEDOT-PSS aqueous dispersion of Production Example 2 (solid content: 1.2 g), 15.0 g of methanol, and 200 g of methyl ethyl ketone was heated and stirred at 60° C. for 3 hours. Next, the mixed solution was returned to room temperature (20 to 25 ° C.) and left to stand for 1 hour, whereupon the highly conductive composite composed of PEDOT-PSS precipitated in the mixed solution, and the upper layer (supernatant) was formed. turned into a clear liquid.
Next, 5.0 g of triglycidyl isocyanurate was added to the mixed solution and stirred for 1 hour to add triglycidyl isocyanurate to the precipitate of the highly conductive composite.
Subsequently, 2.5 g of the highly conductive composite to which the above epoxy compound was added was obtained by filtration. Fractionation of the highly conductive composite by this filtration treatment was completed in 5 minutes or less.
The filtered highly conductive composite was washed with 100 g of acetone and dried. 472.5 g of isopropanol was added to 2.5 g of this highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

(Example 5)
A mixture of 100 g of the PEDOT-PSS aqueous dispersion of Production Example 2 (solid content: 1.2 g), 15.0 g of methanol, and 200 g of methyl ethyl ketone was heated and stirred at 60° C. for 3 hours. Next, the mixed solution was returned to room temperature (20 to 25 ° C.) and left to stand for 1 hour, whereupon the highly conductive composite composed of PEDOT-PSS precipitated in the mixed solution, and the upper layer (supernatant) was formed. turned into a clear liquid.
Next, 5.0 g of diallyl monoglycidyl isocyanurate was added to the mixed solution and stirred for 1 hour to add diallyl monoglycidyl isocyanurate to the deposit of the highly conductive composite.
Subsequently, 2.4 g of the highly conductive composite to which the above epoxy compound was added was obtained by filtration. Fractionation of the highly conductive composite by this filtration treatment was completed in 5 minutes or less.
The filtered highly conductive composite was washed with 100 g of acetone and dried. 472.6 g of isopropanol was added to 2.4 g of this highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

(Example 6)
A conductive film was produced in the same manner as in Example 1, except that isopropanol was changed to methyl ethyl ketone in Example 1 to obtain a methyl ethyl ketone dispersion of a highly conductive composite, and its surface resistance value was measured. Table 1 shows the results.

(Example 7)
To 50 g of the isopropanol dispersion (solid content: 0.24 g) of the highly conductive composite obtained in Example 1, 10 g of Artresin UN-904M (manufactured by Negami Kogyo Co., Ltd., urethane acrylate, solid content: 80%, methyl ethyl ketone solution) was added. , 30 g of pentaerythritol triacrylate, 2.5 g of hydroxyethylacrylamide, 10 g of diacetone alcohol, and 1.6 g of Irgacure 184 (manufactured by BASF, photopolymerization initiator) were added and stirred to obtain a paint. Subsequently, using a #16 bar coater, the paint was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.), dried at 100° C. for 1 minute, and irradiated with ultraviolet rays of 400 mJ to form a conductive film. Obtained. The surface resistance value of the hard coat type conductive film thus obtained was measured. Table 1 shows the results.

(Comparative example 1)
A mixed solution obtained by adding 215 g of isopropanol to 100 g of the PEDOT-PSS aqueous dispersion of Production Example 2 (solid content: 1.2 g) was heated and stirred at 60° C. for 3 hours. Next, the mixed solution was returned to normal temperature and allowed to stand still for 1 hour, but the conductive composite was not precipitated, and it was confirmed that the mixed solution was homogeneous. To this mixed solution, 5.0 g of butylene oxide was added and stirred for 1 hour to add butylene oxide to the conductive composite and deposit it. Subsequently, 2.0 g of the conductive composite to which the epoxy compound was added was obtained by filtration. It took 5 hours to collect the precipitate by this filtration treatment.
The conductive composite collected by filtration was washed with 100 g of acetone and dried. 473.0 g of isopropanol was added to 2.0 g of this conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

(Comparative example 2)
A precipitate was formed in the same manner as in Comparative Example 1, except that 5.0 g of butylene oxide in Comparative Example 1 was changed to 5.0 g of 1,2-epoxy-4-vinylcyclohexane. Subsequently, 2.1 g of the conductive composite to which the epoxy compound was added was obtained by filtration. It took 5 hours to collect the precipitate by this filtration treatment.
The conductive composite collected by filtration was washed with 100 g of acetone and dried. 472.9 g of isopropanol was added to 2.1 g of this conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

(Comparative Example 3)
An attempt was made to form a precipitate in the same manner as in Comparative Example 1, except that 5.0 g of butylene oxide in Comparative Example 1 was changed to 5.0 g of glycidol. However, since no precipitate was formed, the preparation of the conductive film was stopped.

(Comparative Example 4)
A precipitate was formed in the same manner as in Comparative Example 1, except that 5.0 g of butylene oxide was changed to 5.0 g of triglycidyl isocyanurate, and its filtration was attempted. However, the filter paper was clogged and the precipitate could not be filtered out even after spending 5 hours, so the preparation of the conductive film was stopped.

(Comparative Example 5)
A precipitate was formed in the same manner as in Comparative Example 1, except that 5.0 g of butylene oxide in Comparative Example 1 was changed to 5.0 g of diallyl monoglycidyl isocyanurate. Subsequently, 2.2 g of the conductive composite to which the epoxy compound was added was obtained by filtration. It took 5 hours to collect the precipitate by this filtration treatment.
The conductive composite collected by filtration was washed with 100 g of acetone and dried. 472.8 g of isopropanol was added to 2.2 g of this conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the conductive composite. Next, using a #14 bar coater, a portion of the isopropanol dispersion was applied onto a PET film (Lumirror T60 manufactured by Toray Industries, Inc.) and dried at 150° C. for 1 minute to obtain a conductive film. Table 1 shows the results of measuring the surface resistance of the obtained conductive film.

<Evaluation>
Table 1 shows the results of measuring the surface resistance value of the conductive film of each example. For the measurement, a resistivity meter (Hiresta manufactured by Mitsubishi Chemical Analytech Co., Ltd.) was used, and the applied voltage was 10V. Each measurement result is shown in Table 1. "Ω/□" in the table means ohms per square. Also, "1.0E+05" represents "1.0×10 ⁵ ".
The smaller the surface resistance value (unit: Ω/□), the higher the conductivity.

From the above results, it is clear that the production method according to the present invention can easily fractionate the hydrophobized highly conductive composite by filtration. In addition, the highly conductive composite obtained by the production method according to the present invention can be easily dispersed in an organic solvent, and a conductive layer comprising a cured layer of a composition (paint) containing the highly conductive composite. It is clear that the layer has excellent electrical conductivity.

Claims (14)

A mixed solution is obtained by mixing an aqueous dispersion of a conductive composite containing a π-conjugated conductive polymer and a polyanion with an organic solvent containing methyl ethyl ketone and methanol , and a highly conductive composite is deposited in the mixed solution. After letting
A method for producing a highly conductive composite, comprising: adding an epoxy compound to the mixed liquid to separate the highly conductive composite to which the epoxy compound is added. The method for producing a highly conductive composite according to claim 1, wherein the content of the organic solvent contained in the mixed liquid is 50% by mass or more with respect to the total mass of the mixed liquid. The method for producing a highly conductive composite according to claim 1 or 2, wherein the organic solvent contains at least one of a ketone solvent and an alcohol solvent. The method for producing a highly conductive composite according to claim 3, wherein the organic solvent contains a ketone solvent, and the ketone solvent contains methyl ethyl ketone. 4. The method for producing a highly conductive composite according to claim 3, wherein the organic solvent contains an alcohol solvent, and the alcohol solvent contains methanol. The method for producing a highly conductive composite according to any one of claims 1 to 5 , wherein the mixed liquid is heated to 40°C or higher when depositing the highly conductive composite in the mixed liquid. When the highly conductive composite is deposited in the mixed liquid, the content of at least one of the acid and the base other than the polyanion in the mixed liquid is 0.1 mass with respect to the total mass of the mixed liquid. % or less, the method for producing a highly conductive composite according to any one of claims 1 to 6 . The method for producing a highly conductive composite according to any one of claims 1 to 7 , wherein the method for separating the highly conductive composite to which the epoxy compound is added is filtration. The method for producing a highly conductive composite according to any one of claims 1 to 8 , wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene). The method for producing a highly conductive composite according to any one of claims 1 to 9 , wherein the polyanion is polystyrene sulfonic acid. A method for producing an organic solvent dispersion of a highly conductive composite, comprising mixing the highly conductive composite obtained by the production method according to any one of claims 1 to 10 with an organic solvent. 12. The method for producing an organic solvent dispersion of a highly conductive composite according to claim 11 , further comprising mixing a binder component. 13. The method for producing a highly conductive composite organic solvent dispersion according to claim 12 , wherein the binder component is a compound that forms an acrylic resin after curing. Obtaining an organic solvent dispersion of a highly conductive composite by the production method according to any one of claims 11 to 13 ;
A method for producing a conductive film, comprising applying an organic solvent dispersion of the highly conductive composite to at least one surface of a film substrate, and drying the formed coating film.