JP7311412B2 - Method for producing highly conductive composite, method for producing aqueous dispersion of highly conductive composite, method for producing organic solvent dispersion of highly conductive composite, method for producing conductive film - Google Patents

Description

The present invention relates to a method for producing a highly conductive composite, a method for producing an aqueous dispersion of 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.

As a paint for forming a conductive layer on a plastic film, a conductive polymer-containing liquid containing a conductive composite in which poly(3,4-ethylenedioxythiophene) is doped with polystyrenesulfonic acid may be used. .
Patent Document 1 proposes a method of adding an amine compound to an anion group of a conductive composite to make the conductive composite hydrophobic in order to improve the wettability of a liquid containing a conductive polymer to a plastic film. It is

JP 2018-53191 A

However, the conductivity of the conductive layer formed by coating the amine adduct of the conductive composite is not necessarily satisfactory, and further improvement in conductivity is desired.
The present invention provides a method for producing a highly conductive composite capable of forming a conductive layer with excellent conductivity, a method for producing an aqueous dispersion of a highly conductive composite, and an organic solvent dispersion of a highly conductive composite. A method for producing a conductive film and a method for producing the same A method for producing a conductive composite is provided.

[1] A mixed solution is obtained by mixing an organic solvent with a prepared solution containing a conductive composite containing a π-conjugated conductive polymer and a polyanion, a transition metal ion, and an aqueous dispersion medium, and A method for producing a highly conductive composite, comprising depositing a highly conductive composite on a substrate and separating the deposited highly conductive composite.
[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 method for producing a highly conductive composite according to [1] or [2], wherein the organic solvent contains isopropanol and ethyl acetate.
[8] The method for producing a highly conductive composite according to [7], wherein the organic solvent further contains methyl ethyl ketone.
[9] separating the transition metal ions contained in the mixed liquid from the highly conductive composite when separating the highly conductive composite precipitated in the mixed liquid, [1] to [8]; A method for producing a highly conductive composite according to any one of .
[10] When the highly conductive composite is deposited in the mixed solution, the mixed solution of [1] to [9] contains at least one of a counter anion of the transition metal ion and an oxidizing agent. A method for producing a highly conductive composite according to any one of the items.
[11] The highly conductive composite according to any one of [1] to [10], wherein the method for fractionating the highly conductive composite precipitated in the mixed solution is filtration or decantation. manufacturing method.
[12] The method for producing a highly conductive composite according to any one of [1] to [11], wherein the π-conjugated conductive polymer is poly(3,4-ethylenedioxythiophene).
[13] The method for producing a highly conductive composite according to any one of [1] to [12], wherein the polyanion is polystyrenesulfonic acid.
[14] Obtaining a mixed solution by mixing an organic solvent with a prepared solution containing a conductive composite containing a π-conjugated conductive polymer and a polyanion, a transition metal ion, and an aqueous dispersion medium, After depositing a highly conductive composite in the high A method for producing a conductive composite.
[15] A highly conductive composite comprising mixing a highly conductive composite obtained by the production method according to any one of [1] to [13] and an aqueous solvent containing water. A method for producing an aqueous dispersion.
[16] A method for producing an aqueous dispersion of a highly conductive composite according to [15], further comprising mixing a binder component.
[17] A highly conductive composite comprising mixing a highly conductive composite obtained by the production method according to any one of [1] to [13], an organic solvent, and an amine compound. A method for producing an organic solvent dispersion.
[18] 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 [14] with an organic solvent.
[19] A method for producing an organic solvent dispersion of a highly conductive composite according to [17] or [18], further comprising mixing a binder component.
[20] The method for producing an organic solvent dispersion of a highly conductive composite according to [19], wherein the binder component is a compound that forms an acrylic resin after curing.
[21] An aqueous dispersion of the highly conductive composite obtained by the production method described in [15] or [16], or any one of [17] to [20], on at least one surface of the film substrate A method for producing a conductive film, comprising applying an organic solvent dispersion of the highly conductive composite obtained by the production method according to 1 above, and drying the formed coating film.
[22] A conductive layer comprising a cured layer of the aqueous dispersion of the highly conductive composite obtained by the production method according to [15] or [16] on at least one surface of the film substrate, or [17] A conductive film comprising a conductive layer comprising a cured layer of an organic solvent dispersion of a highly conductive composite obtained by the production method according to any one of [20].

INDUSTRIAL APPLICABILITY According to the method for producing a highly conductive composite of the present invention, the highly conductive composite can be easily fractionated without requiring a reaction to hydrophobize the anionic groups possessed by the highly conductive composite. The fractionated highly conductive composite is hydrophilic and can be easily dispersed in water. Further, if necessary, it is easy to add an amine compound to the highly conductive composite to make it hydrophobic. Therefore, the hydrophobized highly conductive composite can be easily dispersed in an organic solvent. Surprisingly, 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 solution by mixing an organic solvent with a prepared solution containing a conductive composite containing a π-conjugated conductive polymer and a polyanion, a transition metal ion, and an aqueous dispersion medium. A method for producing a highly conductive composite, comprising depositing a highly conductive composite in the mixed solution and separating the deposited highly conductive composite.

[Preparation solution]
The preparation liquid used in this embodiment contains a conductive complex containing a π-conjugated conductive polymer and a polyanion, transition metal ions, and an aqueous dispersion medium. This preparation liquid may contain an organic solvent as long as the conductive composite in the liquid is in a dispersed state.

As the preparation liquid used in this embodiment, the reaction liquid prepared for oxidative polymerization of the monomer of the π-conjugated conductive polymer can be applied as it is. The preparation liquid may contain an oxidizing agent used when the monomer is oxidatively polymerized. The preparation liquid may contain a transition metal ion and a counter anion of the transition metal ion as a catalyst for promoting oxidative polymerization.
In the method for producing a highly conductive composite of this aspect, even if the prepared liquid contains an oxidizing agent and a catalyst, a mixed liquid obtained by mixing an organic solvent with the prepared liquid is obtained to deposit a highly conductive composite. The oxidizing agent and the catalyst can be easily separated from the highly conductive composite by separating the highly conductive composite.

(Conductive composite)
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 preparation liquid 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 prepared liquid. On the other hand, the transparency of the prepared liquid in the precipitated state 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 prepared liquid used in this embodiment is passed through a filter having a retention particle size of 7 μm, the dispersed conductive composites pass 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 determined 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 preparation solution>
A conductive composite containing a π-conjugated conductive polymer and a polyanion can be obtained, for example, by chemically oxidatively polymerizing a monomer that forms a π-conjugated conductive polymer in an aqueous solution of the polyanion. The reaction liquid of this chemical oxidation polymerization can be used as it is as the preparation liquid of this embodiment.

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 preparation solution of this embodiment is preferably, for example, 0.1% by mass or more and 20% by mass or less, and 0.5% by mass or more and 10% by mass, relative to the total mass of the preparation solution. % or less is preferable, and 1.0 mass % or more and 5.0 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 preparation solution is increased, preventing unintended aggregation during storage of the preparation solution, and the quality of the highly conductive composite that precipitates after the addition of the organic solvent. can be made uniform.

The preparation liquid used in this embodiment may contain an organic solvent to the extent that the conductive composite is in a dispersed state. It is preferable that the content of the organic solvent is as small as possible, and it is more preferable that the organic solvent is not substantially contained. is more preferred.
As the organic solvent that may be contained in the preparation liquid used in this embodiment, one having high miscibility with water is preferable, and examples thereof include alcohol-based solvents described later.

[Mixture]
Examples of the method for obtaining a mixed liquid by mixing the preparation liquid and the organic solvent include a method of adding an organic solvent to the preparation liquid, a method of adding the preparation liquid to the organic solvent, and the like. A preferred embodiment includes a method of gradually adding the organic solvent while stirring the prepared solution. With this addition method, it is possible to prevent the concentration of the organic solvent in the prepared liquid from sharply increasing locally, and to precipitate the highly conductive composite gently. 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 65% 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 preparation liquid 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.
When it is equal to or less than the upper limit of the above range, the amount of preparation liquid 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 after mixing the preparation liquid 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. 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 liquid mixture of this aspect 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.

In the mixed solution of this aspect, the content of acid or base other than the polyanion is preferably 0.1% by mass or less with respect to the total mass of the mixed solution, and is 0.01% by mass or less. It is more preferred to be present, and most preferably substantially absent.
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 acid or base described above can be a cause of inhibiting the deposition of the highly conductive composite in the liquid mixture of this embodiment.

The mixed solution of this embodiment contains one or more transition metal ions derived from the preparation solution.
Transition metal ions include cations of first transition elements such as iron and copper.
Counter anions of transition metal ions include anions such as chlorine, bromine, sulfuric acid and nitric acid.
When the transition metal ions are derived from the catalyst for oxidative polymerization of the monomers of the π-conjugated conductive polymer, the amount of the transition metal ions in the prepared liquid is, for example, 0.001% by mass or more and 0.5% by mass or less, preferably 0.005% by mass or more and 0.25% by mass or less, and more preferably 0.01% by mass or more and 0.1% by mass or less.
Since the mixed solution is obtained by diluting the prepared solution with the organic solvent, the amount of transition metal ions contained in the mixed solution is, for example, 0.0001% by mass or more with respect to the total mass of the mixed solution. 0.4% by mass or less, preferably 0.0005% by mass or more and 0.1% by mass or less, and more preferably 0.001% by mass or more and 0.05% by mass or less are listed as a guideline.

The mixed liquid of this aspect may contain one or more oxidizing agents derived from the preparation liquid. Examples of the oxidizing agent include those used to oxidatively polymerize the monomers of the π-conjugated conductive polymer.
When the oxidizing agent is used for oxidative polymerization of the monomer of the π-conjugated conductive polymer, the amount of the oxidizing agent in the prepared liquid is, for example, 0.005% relative to the total mass of the prepared liquid. It is contained as a standard of 1% by mass or more and 5% by mass or less, preferably 0.5% by mass or more and 3% by mass or less, more preferably 1% by mass or more and 2% by mass or less.
Since the mixed solution is obtained by diluting the prepared solution with the organic solvent, the amount of the oxidizing agent contained in the mixed solution is, for example, 0.01% by mass or more with respect to the total mass of the mixed solution. 4% by mass or less, preferably 0.1% by mass or more and 2% by mass or less, more preferably 0.2% by mass or more and 1% by mass or less is a standard.

[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 allow 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 liquid, the highly conductive composite can be easily deposited in the mixed liquid, and the yield of the conductive composite can be improved.

[Preparation of Highly Conductive Complex]
The method of separating (collecting) the highly conductive composite precipitated in the mixed solution is not particularly limited, and examples thereof include filtration, decantation, centrifugation, vacuum drying, freeze drying, spray drying, and the like.
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, so decantation can fractionate more easily. 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. Therefore, it is more preferable to fractionate the highly conductive composite by decantation.

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, 90 to 100 parts by mass of the highly conductive composite is recovered as a precipitate with respect to 100 parts by mass of the conductive composite contained in the mixed liquid. can be done. 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 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 using the highly conductive composite precipitated in the production method of the present invention, it is more effective than when using a conventional conductive composite (for example, a conductive composite obtained by freeze-drying a raw material). , a conductive layer having excellent conductivity can be formed (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. By using the highly conductive composite obtained by the production method of the present invention, the highly conductive composite having a particle size smaller than that of the conventional conductive composite can be dispersed in the paint. As a result, it is presumed that the conductivity of the conductive layer formed from the coating film of the paint is increased.

In the method for producing a highly conductive composite of the present invention, the mixed liquid for depositing the highly conductive composite may contain an oxidizing agent and a catalyst. Therefore, it is not necessary to previously remove the oxidizing agent and the catalyst from the prepared liquid, which is the raw material of the mixed liquid. Since the reaction liquid obtained by oxidative polymerization for forming the π-conjugated conductive polymer can be used as the preparation liquid, the production efficiency of the highly conductive composite is very high. If the oxidizing agent and the catalyst were to be removed from the prepared solution in advance, the prepared solution would need to be treated by ion exchange, gel filtration, ultrafiltration, or the like, which would increase production costs. On the other hand, in the production method of the present invention, it is not necessary to perform these treatments, and a highly conductive composite with improved conductivity is separated through precipitation, and an unnecessary oxidizing agent or catalyst is added to the mixed solution in the subsequent steps. Since it can be easily separated while remaining inside, the manufacturing cost can be reduced.

<<Method for Producing Aqueous Dispersion of Highly Conductive Composite>>
A second aspect of the present invention is the production of an aqueous dispersion of a highly conductive composite, comprising mixing the highly conductive composite obtained by the production method of the first aspect with an aqueous dispersion medium containing water. The method.
Since the highly conductive composite obtained in the first mode has high dispersibility in water, it can be easily dispersed in an aqueous dispersion medium containing water.
The highly conductive composite used in this embodiment may be dried and stored after being fractionated by the production method of the first embodiment, or may be used immediately without storage.

The aqueous dispersion medium of this embodiment may contain an organic solvent. As the organic solvent, a water-soluble organic solvent is preferred. Here, the water-soluble organic solvent is an organic solvent that dissolves in 100 g of water at 20° C. in an amount of 1 g or more.
Examples of water-soluble organic solvents include alcohol-based solvents, ketone-based solvents, and ester-based solvents, with alcohol-based solvents being preferred. Specific examples of the water-soluble organic solvent are omitted because they are the same as those described in the first embodiment.

The content of water in the total mass of the aqueous dispersion medium of the present embodiment can be, for example, 5% by mass or more and 100% by mass or less, preferably 50% by mass or more and 100% by mass or less, and 70% by mass or more and 100% by mass. The following are more preferred.

In this embodiment, the method of mixing the highly conductive composite and the aqueous dispersion medium is not particularly limited, and includes, for example: (1) a method of adding an aqueous dispersion medium to the highly conductive composite and stirring; For example, water is added to the conductive composite to obtain an aqueous dispersion of the highly conductive composite, and then an organic solvent is added as necessary, followed by stirring.
Since the dispersibility of the highly conductive composite in water is very high, the method (2) is preferable from the viewpoint of preventing the particles from increasing in size due to aggregation of the highly conductive composite.

After the highly conductive composite and the aqueous dispersion medium are mixed, the mixed liquid may be stirred for dispersion 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 homogenizer).

In the aqueous dispersion of the highly conductive composite of this embodiment, the particle size distribution of the dispersed highly conductive composite 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. As for the lower limit, since the highly conductive composite contains a polymer, considering the molecular radius of the polymer, 1 nm or more is a standard.
As the particle size distribution becomes smaller, the conductivity of the conductive layer formed by applying the aqueous 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 aqueous dispersion of the highly conductive composite of the present embodiment is, for example, preferably 0.1% by mass or more and 20% by mass or less, and 0.5% by mass or more and 10% by mass. % by mass or less is more preferable, and 1.0% by mass or more and 5.0% by mass or less is even more preferable.
Within the above range, the highly conductive composite can be more stably dispersed.

(binder component)
The aqueous 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.

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 aqueous dispersion of the highly conductive composite of this embodiment, a water-dispersible resin is preferable, and a water-dispersible emulsion resin is more preferable. Water-dispersible resins are emulsion resins or water-soluble resins.

Specific examples of water-dispersible emulsion resins include acrylic resins (acrylic compounds), polyester resins, polyurethane resins, polyimide resins, melamine resins, etc., which are emulsified with an emulsifier. Among them, a polyester emulsion is preferable because the strength of a coating film (conductive film) obtained by coating a film substrate with the aqueous dispersion of the highly conductive composite of the present embodiment is increased. In particular, when coating on a polyester film substrate, a polyester emulsion is preferable because the adhesion of the coating film to the film substrate increases.

Specific examples of water-soluble resins include acrylic resins (acrylic compounds), polyester resins, polyurethane resins, polyimide resins, and melamine resins having an acid group such as a carboxy group or a sulfo group, or a salt thereof. Here, the water-soluble resin preferably dissolves in 100 g of distilled water at 25° C. in an amount of 1 g or more, preferably 5 g or more, more preferably 10 g or more.

Acid groups such as carboxy groups and sulfo groups in the binder resin may form salts with cations such as sodium ions and potassium ions.

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

The content of the binder component in the aqueous dispersion of the highly conductive composite of this embodiment is preferably 100 parts by mass or more and 20000 parts by mass or less, and 500 parts by mass or more, relative to 100 parts by mass of the highly conductive composite. It is more preferably 5000 parts by mass or less. 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 aqueous 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.

<<Method for producing organic solvent dispersion of highly conductive composite>>
A third aspect of the present invention is the production of an organic solvent dispersion of a highly conductive composite, comprising mixing the highly conductive composite obtained by the production method of the first aspect, an organic solvent, and an amine compound. The method.
The highly conductive composite obtained in the first mode has high dispersibility in water and low dispersibility in organic solvents. Therefore, by adding an amine compound together with an organic solvent to the highly conductive composite, adding the amine compound to the anion group of the polyanion constituting the highly conductive composite, and hydrophobizing the highly conductive composite, A highly conductive composite can be dispersed in an organic solvent.
The highly conductive composite used in this embodiment may be dried and stored after being fractionated by the production method of the first embodiment, or may be used immediately without storage.

(amine compound)
The amine compound is at least one selected from the group consisting of primary amines, secondary amines and tertiary amines. An amine compound may be used individually by 1 type, and may use 2 or more types together.
Examples of primary amines include aniline, toluidine, benzylamine, ethanolamine and the like.
Secondary amines include, for example, diethanolamine, dimethylamine, diethylamine, dipropylamine, diphenylamine, dibenzylamine, dinaphthylamine and the like.
Tertiary amines include, for example, triethanolamine, trimethylamine, triethylamine, tripropylamine, tributylamine, trihexylamine, trioctylamine, triphenylamine, tribenzylamine, and trinaphthylamine.
Among the amine compounds, tertiary amines are preferable, and at least one of trioctylamine and tributylamine is more preferable, since the highly conductive composite can be easily hydrophobized.

The amine compound preferably has a substituent with 6 or more carbon atoms on the nitrogen atom because it is highly dispersible in low-polarity organic solvents. It is more preferable to have

The organic solvent dispersion of the highly conductive composite contains the aforementioned highly conductive composite, an amine compound added thereto, and an organic solvent. Since the organic solvent can disperse or dissolve the highly conductive composite, it can be called a dispersion medium or a solvent. 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.

(Organic solvent)
Examples of the organic solvent used in the production method of this embodiment include 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 base increases 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 amine 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, the organic solvent, and the amine compound is not particularly limited. (B) A method of adding an amine compound to a highly conductive composite to obtain a hydrophobized highly conductive composite, then further adding an organic solvent and stirring.
The method (A) is preferred from the viewpoint of increasing the efficiency of the addition reaction of the amine compound to the polyanion of the highly conductive composite.

In this embodiment, the method of mixing the highly conductive composite, the organic solvent and the amine compound is preferably a method of mixing these and dispersing them while mixing with a high-pressure homogenizer.

When the highly conductive composite is mixed with the amine compound and the organic solvent, the amine compound is added to the highly conductive composite, and the highly conductive composite is hydrophobized. Although the hydrophobized highly conductive composite is dispersed in this mixed liquid, the mixed liquid may be continuously stirred and subjected to further dispersion 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 homogenizer).

In the organic solvent dispersion obtained by the production method of this embodiment, the highly conductive composite to which the amine compound is added is in a dispersed state.
Although the particle size distribution of the dispersed highly conductive composite is not particularly limited, it is preferably 300 nm or less, more preferably 250 nm or less, and even more preferably 200 nm or less. As for the lower limit, since the highly conductive composite contains a polymer, considering the molecular radius of the polymer, 1 nm or more is a standard.
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, a polyurethane resin, and a polyester resin are preferable because of their good dispersibility in organic solvents. More preferred are compounds that form acrylic resins after curing, and polyurethane resins.

The content of the binder component in the organic solvent dispersion of the highly conductive composite of this embodiment is preferably 500 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 aqueous 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.

<<Method for producing organic solvent dispersion of highly conductive composite>>
A fourth aspect of the present invention is to obtain a mixed solution obtained by mixing an organic solvent with a prepared solution containing a conductive composite containing a π-conjugated conductive polymer and a polyanion, a transition metal ion, and an aqueous dispersion medium. , after depositing a highly conductive composite in the mixed solution, an amine compound is added to the mixed solution containing the highly conductive composite, and the highly conductive composite to which the amine compound is added is fractionated. A method for producing a highly conductive composite, comprising:

In this embodiment, the method up to the method of depositing the highly conductive composite in the mixed solution is the same as the method of the first embodiment, and redundant description will be omitted.
The explanation of the addition of the amine compound below includes the explanation common to the addition of the amine compound in the aforementioned third aspect.

[Addition of amine compound]
By adding an amine compound to the mixed solution in which the highly conductive composite is deposited, the amine 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.
It is considered that the structure of the substituent in which the amine compound is added to the surplus anion group that does not participate in the doping of the polyanion is the structure represented by the following chemical formula (X).
—HN ⁺ R ²¹ R ²² R ²³ (X)
[In formula (X), R ²¹ to R ²³ are each independently a hydrogen atom or a hydrocarbon group which may have a substituent, provided that at least one of R ²¹ to R ²³ is a substituent is a hydrocarbon group which may have ]

In formula (X), the bond on the left end represents that the negative charge of the anion group and the positive charge of the amine compound are bonded. Examples of negatively charged anionic groups include anionic groups in which active protons are bonded to oxygen atoms, such as “—SO ₃ ⁻ ”.

R ²¹ to R ²³ in formula (X) are hydrogen atoms or hydrocarbon groups which may have a substituent. R ²¹ to R ²³ in formula (X) are substituents derived from an amine compound.
The hydrocarbon group in the formula (X) is an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms, an optionally substituted aromatic hydrocarbon group having 6 to 20 carbon atoms. groups.
Examples of aliphatic hydrocarbon groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl and octyl groups.
A phenyl group, a hydroxyl group, etc. are mentioned as a substituent of an aliphatic hydrocarbon group.
A phenyl group, a naphthyl group, etc. are mentioned as an aromatic-hydrocarbon group.
Substituents for the aromatic hydrocarbon group include alkyl groups having 1 to 5 carbon atoms, hydroxyl groups and the like.

(amine compound)
The amine compound is at least one selected from the group consisting of primary amines, secondary amines and tertiary amines. An amine compound may be used individually by 1 type, and may use 2 or more types together.
Specific examples of the amine compound are the same as the examples of the amine compound in the third embodiment, so overlapping explanations are omitted.

Since the dispersibility of the highly conductive composite to which the amine compound is added to the low-polarity organic solvent increases, the amine compound added to the mixed solution has a substituent having 4 or more carbon atoms on the nitrogen atom. It is more preferable to have a substituent with 6 or more carbon atoms on the nitrogen atom, and it is even more preferable to have a substituent with 8 or more carbon atoms on the nitrogen atom.

A method for adding the amine compound to the mixed solution is not particularly limited. Since the mixed solution contains an organic solvent to the extent that the highly conductive composite is deposited, the hydrophobic amine compound can be sufficiently dissolved.

The amount of the amine 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 10 parts by mass or more and 5000 parts by mass or less, and more preferably 50 parts by mass or more and 1000 parts by mass or less. If the addition ratio of the amine 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 complex to which the amine 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.

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.

The highly conductive composite obtained by the production method of this embodiment is hydrophobized by addition of an amine compound. The highly conductive composite hydrophobized in this way has high dispersibility in organic solvents. Therefore, as described in the third aspect, by mixing the hydrophobized highly conductive composite with an organic solvent, an organic solvent dispersion of the highly conductive composite can be produced.
A binder component can be added to the organic solvent dispersion of the highly conductive composite as in the third embodiment.

≪Other Additives≫
The aqueous dispersion and 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, polyanion, organic solvent, and 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-described aqueous dispersion and organic solvent dispersion of the highly conductive composite contain the above-mentioned additive, the content ratio is appropriately determined according to the type of additive. It can be in the range of 0.001 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the solid content.

<Effect>
The aqueous dispersion and organic solvent dispersion of the highly conductive composite obtained by the production method of the present invention are excellent in dispersibility of the highly conductive composite, and therefore are formed from the aqueous dispersion and the organic solvent dispersion. The dispersibility of the highly conductive composite in the conductive layer is also excellent. 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 aqueous dispersion and the organic solvent dispersion can also be improved.

≪Method for producing conductive film≫
A fifth aspect of the present invention is an aqueous dispersion of the highly conductive composite obtained by the production method of the second aspect, or the production method of the third aspect or the fourth aspect, on at least one surface of the film substrate. A method for producing a conductive film, comprising applying an organic solvent dispersion of the obtained highly conductive composite and drying the formed coating film.

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 and cellulose triacetate are preferable because they are inexpensive and have 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 formed from the conductive polymer-containing liquid.

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 the dispersion of the highly conductive composite to the film substrate include gravure coaters, roll coaters, curtain flow coaters, spin coaters, bar coaters, reverse coaters, kiss coaters, fountain coaters, 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, rotor dampening, and immersion methods such as dipping. 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 sixth aspect of the present invention is a conductive layer made of a cured layer of the aqueous dispersion of the highly conductive composite obtained by the production method of the second aspect on at least one surface of the film substrate, or a third aspect or A conductive film comprising a conductive layer comprising a cured layer of an organic solvent dispersion of a highly conductive composite obtained by the manufacturing method of the fourth aspect. The conductive film of this aspect can be produced by the production method of the fifth 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 a highly conductive composite. An amine compound may be added to some or all of the surplus anionic groups of the polyanion that constitutes the highly conductive composite.
When the applied 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 aspect is, for example, preferably 10 nm or more and 50 μm or less, more preferably 20 nm or more and 30 μm or less, and even more preferably 30 nm or more and 20 μm 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 conductive layer of the conductive film of this embodiment preferably has a surface resistance value of, for example, 1×10 ² Ω/□ or more and 1×10 ⁸ Ω/□ or less as a measure of good conductivity. It more preferably has a surface resistance value of ³ Ω/□ or more and 1×10 ⁷ Ω/□ or less, and further preferably has a surface resistance value of 1×10 ⁴ Ω/□ or more and 1×10 ⁶ Ω/□ or less. .

<Effect>
Since the conductive layer of the conductive film of the sixth 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 1.14 g of an ammonium persulfate oxidizing agent solution previously dissolved in 10 ml of water was added while stirring at 80°C. 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 six times.
Water in the obtained solution was removed under reduced pressure to obtain a colorless solid polystyrene sulfonic acid.

(Production Example 2) Conductive polymer preparation solution 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. .
The mixed solution thus obtained was kept at 20° C., and while stirring, 29.64 g of ammonium persulfate dissolved in 200 ml of ion-exchanged water and 8.0 g of ferric sulfate oxidation catalyst solution were slowly added, The mixture was stirred for 3 hours to react.
This resulted in a preparation containing 1.2% poly(3,4-ethylenedioxythiophene) (PEDOT-PSS) doped with polystyrene sulfonate, about 0.098% by weight iron ions, and about 1.3% by weight ammonium persulfate. I got the liquid. Here, the PSS content relative to the PEDOT-PSS solid content is 75% by mass.

(Production Example 3) Synthesis of conductive polymer aqueous 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 dissolved in 200 ml of ion-exchanged water and 8.0 g of ferric sulfate oxidation catalyst solution 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 solution 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 an aqueous dispersion of 1.2% polystyrenesulfonic acid-doped poly(3,4-ethylenedioxythiophene) (PEDOT-PSS aqueous dispersion). The content of PSS with respect to PEDOT-PSS solid content is 75% by mass.
The PEDOT-PSS aqueous dispersion obtained here does not substantially contain iron ions or ammonium persulfate.

(Production Example 4) Production of Freeze-Dried Body 100 g of the PEDOT-PSS aqueous dispersion obtained in Production Example 3 was freeze-dried to obtain 1.2 g of a freeze-dried body of PEDOT-PSS (conductive composite).

(Example 1)
A mixed solution obtained by adding 12.5 g of methanol and 200 g of methyl ethyl ketone to 100 g of the prepared solution of Production Example 2 was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
Table 1 shows the results of measuring the iron content of the obtained highly conductive composites with fluorescent X-rays.
Next, 60 g of water was added to 1.2 g of the obtained highly conductive polymer composite and dispersed with a high-pressure homogenizer to obtain an aqueous dispersion of a highly conductive composite having a solid content (non-volatile component) of 2% by mass. rice field. An aqueous dispersion of a highly conductive composite obtained by adding 60 g of methanol to this aqueous dispersion (solid content: about 1.0% by mass) was coated on a PET film (Lumirror T60, manufactured by Toray Industries, Inc.) using a #8 bar coater. A conductive film was obtained by coating on top and drying at 150° C. for 1 minute.

(Example 2)
A mixed solution obtained by adding 25 g of methanol and 200 g of methyl ethyl ketone to 100 g of the prepared solution of Production Example 2 was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
Table 1 shows the results of measuring the iron content of the obtained highly conductive composites with fluorescent X-rays.
A conductive film was produced in the same manner as in Example 1 using the highly conductive composite obtained here.

(Example 3)
A mixture of 100 g of the preparation liquid of Production Example 2, 25 g of isopropanol, 200 g of methyl ethyl ketone, and 17.5 g of ethyl acetate was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
Table 1 shows the results of measuring the iron content of the obtained highly conductive composites with fluorescent X-rays.
A conductive film was produced in the same manner as in Example 1 using the highly conductive composite obtained here.

(Comparative example 1)
212.5 g of water was added to 100 g of the preparation liquid of Production Example 2, and the mixture was stirred at 60° C. for 3 hours. However, since the conductive composite was not deposited, further examination was stopped.

(Comparative example 2)
225 g of water was added to 100 g of the preparation liquid of Production Example 2, and the mixture was stirred at 60° C. for 3 hours. However, since the conductive composite was not deposited, further examination was stopped.

(Comparative Example 3)
242.5 g of water was added to 100 g of the preparation liquid of Production Example 2, and the mixture was stirred at 60° C. for 3 hours. However, since the conductive composite was not deposited, further examination was stopped.

(Comparative Example 4)
Table 1 shows the results of measurement of the iron content of the freeze-dried conductive composite obtained in Production Example 3 using fluorescent X-rays. Next, 60 g of water was added to 1.2 g of this freeze-dried product and dispersed with a high-pressure homogenizer to obtain an aqueous dispersion of a conductive composite having a solid content of 2% by mass. A conductive film was obtained in the same manner as in Example 1, except that this aqueous dispersion was used.

<Evaluation>
Table 1 shows the results of measuring the surface resistance value of the conductive film of each example. At the time of the measurement, a resistivity meter (Hiresta manufactured by Mitsubishi Chemical Analytech Co., Ltd.) was used, and the applied voltage was set to 10V. Each measurement result is shown in Table 1. "Ω/□" in the table means ohms per square. Also, "2.0E+5" represents "2.0×10 ⁵ ".
The smaller the surface resistance value (unit: Ω/□), the higher the conductivity. In the results of Table 1, the conductivity of the conductive films of Examples 1-3 was superior to that of Comparative Example 4.

(Example 4)
A mixed solution obtained by adding 12.5 g of methanol and 200 g of methyl ethyl ketone to 100 g of the prepared solution of Production Example 2 was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
472.74 g of isopropanol and 1.06 g of trioctylamine were added to 1.2 g of the obtained highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite to which trioctylamine was added. got

Next, Artresin UN-904M (manufactured by Negami Kogyo Co., Ltd., urethane acrylate, solid content 80%, methyl ethyl ketone solution) 100 g, pentaerythritol triacrylate 300 g, hydroxyethyl acrylamide 25 g, diacetone alcohol 100 g, Irgacure 184 ( BASF Corporation, photopolymerization initiator) 16.2 g of a highly conductive composite organic solvent dispersion obtained by adding a PET film (manufactured by Toray Industries, Lumirror T60) using a #8 bar coater. , dried at 100°C for 1 minute, and irradiated with 400 mJ ultraviolet rays to obtain a conductive film. Table 2 shows the results of measuring the surface resistance value by the above-described method.

(Example 5)
A mixed solution obtained by adding 25 g of methanol and 200 g of methyl ethyl ketone to 100 g of the prepared solution of Production Example 2 was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
472.74 g of isopropanol and 1.06 g of trioctylamine were added to 1.2 g of the obtained highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite to which trioctylamine was added. got A conductive film was produced in the same manner as in Example 4 except that this dispersion was used, and its surface resistance value was measured.

(Example 6)
A mixture of 100 g of the preparation liquid of Production Example 2, 25 g of isopropanol, 200 g of methyl ethyl ketone, and 17.5 g of ethyl acetate was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
472.74 g of isopropanol and 1.06 g of trioctylamine were added to 1.2 g of the obtained highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite to which trioctylamine was added. got A conductive film was produced in the same manner as in Example 4 except that this dispersion was used, and its surface resistance value was measured.

(Example 7)
A mixed solution obtained by adding 12.5 g of methanol and 200 g of methyl ethyl ketone to 100 g of the prepared solution of Production Example 2 was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
472.74 g of isopropanol and 1.06 g of trioctylamine were added to 1.2 g of the obtained highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite to which trioctylamine was added. got A conductive film was produced in the same manner as in Example 4 except that this dispersion was used, and its surface resistance value was measured.

(Example 8)
A mixed solution obtained by adding 12.5 g of methanol and 200 g of methyl ethyl ketone to 100 g of the prepared solution of Production Example 2 was stirred at 60° C. for 3 hours. Next, the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution was collected by filtration and washed with 100 g of isopropanol to obtain 1.2 g of the highly conductive composite.
473.24 g of isopropanol and 0.56 g of tributylamine were added to 1.2 g of the obtained highly conductive composite, and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite to which tributylamine was added. rice field. A conductive film was produced in the same manner as in Example 4 except that this dispersion was used, and its surface resistance value was measured.

(Example 9)
A mixed liquid obtained by adding 15.0 g of methanol and 200 g of methyl ethyl ketone to 100 g of the preparation liquid of Production Example 2 was stirred at 60° C. for 3 hours. Next, the mixed solution was allowed to stand and waited for 1 hour until the highly conductive composite composed of PEDOT-PSS deposited in the mixed solution spontaneously settled to the bottom of the container. Thereafter, 200 g of the supernatant was removed by decantation, 300 g of isopropanol was added, and the mixture was stirred. Thereafter, 300 g of the supernatant liquid was again removed by decantation, 300 g of isopropanol was added, and the mixture was stirred. After that, 300 g of the supernatant liquid was further removed by decantation to obtain 115 g of an isopropanol mixed liquid containing a highly conductive composite.
358.94 g of isopropanol and 1.06 g of trioctylamine were added to 115 g of the isopropanol mixture containing the obtained highly conductive composite and dispersed with a high-pressure homogenizer to obtain a highly conductive composite to which trioctylamine was added. An isopropanol dispersion was obtained.
A conductive film was produced in the same manner as in Example 4 except that this dispersion was used, and its surface resistance value was measured.

(Example 10)
A mixed solution obtained by adding 12.5 g of methanol and 200 g of methyl ethyl ketone to 100 g of the prepared solution of Production Example 2 was stirred at 60° C. for 3 hours. Next, after confirming that a highly conductive composite made of PEDOT-PSS is deposited in the mixed liquid, 5.0 g of trioctylamine is added to the mixed liquid, and a highly conductive trioctylamine-added high conductive The complex was collected by filtration and washed with 100 g of methyl ethyl ketone to obtain 2.3 g of trioctylamine-added highly conductive complex.
472.74 g of isopropanol was added to 2.3 g of the obtained highly conductive composite and dispersed with a high-pressure homogenizer to obtain an isopropanol dispersion of the highly conductive composite to which trioctylamine was added.
A conductive film was produced in the same manner as in Example 4 except that this dispersion was used, and its surface resistance value was measured.

(Comparative Example 5)
To 1.2 g of the freeze-dried PEDOT-PSS of Production Example 4, 472.74 g of isopropanol and 1.06 g of trioctylamine were added and dispersed with a high-pressure homogenizer to obtain a conductive composite to which trioctylamine was added. An isopropanol dispersion was obtained.
A conductive film was produced in the same manner as in Example 4 except that this dispersion was used, and its surface resistance value was measured.

From the above results, by the method for producing a highly conductive composite according to the present invention, a highly conductive composite having excellent conductivity can be obtained while separating from impurities such as iron ions, counter anions of iron ions, and oxidizing agents. was able to separate. Since the fractionated highly conductive composite was hydrophilic, it could be easily dispersed in water. In addition, if necessary, an amine compound was added to the highly conductive composite to make it hydrophobic so that it could be easily dispersed in an organic solvent. Furthermore, it was also possible to add an amine compound to the highly conductive composite precipitated in the mixed solution and separate it.
It is clear that the use of the highly conductive composite according to the present invention can form a conductive layer with excellent conductivity compared to the case of using a conventional conductive composite.

Claims (21)

Obtaining a mixed solution in which an organic solvent is mixed with a prepared solution containing a conductive composite containing a π-conjugated conductive polymer and a polyanion, a transition metal ion, and an aqueous dispersion medium,
Manufacture of a highly conductive composite, comprising heating the mixed liquid at 40 ° C. or higher and 100 ° C. or lower to precipitate a highly conductive composite in the mixed liquid, and separating the precipitated highly conductive composite. is a method,
A method for producing a highly conductive composite, wherein the highly conductive composite is dispersible in water. 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. 4. 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 claim 1 or 2, wherein the organic solvent contains methyl ethyl ketone and methanol. The method for producing a highly conductive composite according to claim 1 or 2, wherein the organic solvent contains isopropanol and ethyl acetate. 8. The method for producing a highly conductive composite according to claim 7, wherein the organic solvent further contains methyl ethyl ketone. 9. The transition metal ion contained in the mixed liquid and the highly conductive composite are separated when separating the highly conductive composite precipitated in the mixed liquid. A method for producing a highly conductive composite according to 1. The liquid mixture according to any one of claims 1 to 9, wherein when the highly conductive composite is deposited in the liquid mixture, at least one of a counter anion of the transition metal ion and an oxidizing agent is contained in the liquid mixture. A method of making the described highly conductive composite. The method for producing a highly conductive composite according to any one of claims 1 to 10, wherein the method for separating the highly conductive composite precipitated in the mixed solution is filtration or decantation. The method for producing a highly conductive composite according to any one of claims 1 to 11, 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 12, wherein the polyanion is polystyrene sulfonic acid. Obtaining a mixed solution in which an organic solvent is mixed with a prepared solution containing a conductive composite containing a π-conjugated conductive polymer and a polyanion, a transition metal ion, and an aqueous dispersion medium,
After depositing the highly conductive composite in the mixed solution,
A method for producing a highly conductive composite, comprising adding an amine compound to the mixed liquid containing the highly conductive composite, and separating the highly conductive composite to which the amine compound is added. Production of an aqueous dispersion of a highly conductive composite, comprising mixing a highly conductive composite obtained by the production method according to any one of claims 1 to 13 and an aqueous solvent containing water. Method. 16. The method for producing an aqueous dispersion of a highly conductive composite according to claim 15, further comprising mixing a binder component. An organic solvent dispersion of a highly conductive composite, comprising mixing a highly conductive composite obtained by the production method according to any one of claims 1 to 13, an organic solvent, and an amine compound. Production method. 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 claim 14 and an organic solvent. 19. The method for producing an organic solvent dispersion of a highly conductive composite according to claim 17 or 18, further comprising mixing a binder component. 20. The method for producing a highly conductive composite organic solvent dispersion according to claim 19, wherein the binder component is a compound that forms an acrylic resin after curing. On at least one surface of the film substrate, an aqueous dispersion of the highly conductive composite obtained by the production method according to claim 15 or 16, or the production method according to any one of claims 17 to 20. A method for producing a conductive film, comprising applying the organic solvent dispersion of the highly conductive composite obtained in 1. and drying the formed coating film.