JP7089099B1 - Conductive pigment pastes, coating materials, and coating films - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive pigment paste and a coating material having excellent pigment dispersibility even at a high pigment concentration, having an appropriate viscosity (low viscosity), excellent storage stability, and excellent conductivity of a coating film. Further, to provide a conductive coating film having excellent finishability and the like. A pigment dispersion resin (A) having an active hydrogen group, a conductive pigment (B), an organic solvent (C), and an organic compound (D) having reactivity with an active hydrogen group are contained and are conductive. A conductive pigment paste in which the pigment (B) contains a carbon nanotube (B-1) and / or a conductive carbon (B-2) having an average primary particle diameter of 10 to 80 nm. [Selection diagram] None

Description

The present invention relates to a conductive pigment paste and a coating material having excellent pigment dispersibility and storage stability even at a high pigment concentration, and a coating film having excellent finishability and the like.

Conventionally, a paste-like pigment dispersion in which a pigment is dispersed in a mixture of a pigment dispersion resin and a solvent has been used as a paint, a coating material, a coating material, an electromagnetic wave shield, a display panel, a touch screen panel, a colored film, a colored sheet, and the like. It is widely used in the fields of decorative materials, protective materials, magnet modifiers, printing inks, device members, electronic device members, printed wiring boards, solar cells, functional rubber members, resin molded films and the like. Further, in order to impart functions such as electrostatic coating property, conductivity, electromagnetic wave shielding property, and antistatic property to these materials, a conductive pigment, a conductive polymer and the like are contained.
In these fields, performance improvements such as pigment dispersibility, storage stability, coatability, conductivity, finish, and solvent resistance are increasingly required, and therefore, excellent pigment dispersion ability and formation have been formed. Pigment dispersion resins and pigment pastes having excellent storage stability that do not reaggregate the pigment particles in the pigment dispersion are being developed.
When designing the pigment paste, make sure that the pigment-dispersed resin does not adversely affect the conductivity performance of the final product itself, such as the coating film, or reduce the amount of solvent and pigment-dispersed resin used, and the energy used during drying. From the viewpoint of reducing the amount of pigment paste, it is important to prepare a pigment paste uniformly dispersed in a high concentration with a small amount of pigment dispersion resin.

Patent Document 1 describes a carbon composite paste containing carbon nanotubes and carbon black as conductive materials, in which carbon nanotubes dispersed in a water-soluble xylan aqueous solution and carbon black dispersed in acetone are mixed and mixed. Is described, and a carbon composite paste prepared by separating a water-soluble xylan aqueous solution and acetone from a mixed solution by filtration is described.
Patent Document 2 describes a conductive agent dispersion containing at least two different carbon materials and a solvent as a conductive auxiliary agent, wherein the first type of conductive auxiliary agent has an average primary particle diameter of 20 to 50 nm. BET specific surface area 300 to 1,400 m ² / g, average dispersed particle diameter 280 to 1,500 nm The second type of conductive auxiliary agent has an average primary particle diameter 20 to 70 nm, BET specific surface area 10 to 200 m ² / g, average dispersion. A conductive auxiliary agent dispersion having a particle size of 500 to 1,500 nm and a mass ratio of the first type of conductive auxiliary agent to the second type of conductive auxiliary agent of 20 to 80:80 to 20 is disclosed.

International Publication No. 2015/064708 Japanese Unexamined Patent Publication No. 2019-61916

The carbon composite paste of Patent Document 1 is for producing a conductive sheet by drying to produce a carbon composite filler, kneading it with a resin material, and heat-molding it. It has not been studied and is not used as a coating material.
The conductive auxiliary agent dispersion liquid of Patent Document 2 may not have sufficient dispersibility because it contains 20% by mass or more of a carbon material having a large specific surface area.

The problem to be solved by the present invention is a conductive pigment paste and coating having excellent pigment dispersibility even at a high pigment concentration, having an appropriate viscosity (low viscosity), excellent storage stability, and excellent conductivity of a coating film. It is to provide work materials. Further, it is to provide a conductive coating film having excellent finishability and the like.

As a result of diligent studies to solve the above problems, the inventors have conducted a pigment dispersion resin (A) having an active hydrogen group, carbon nanotubes (B-1) and / or conductivity having an average primary particle diameter of 10 to 80 nm. The above-mentioned problems are solved by the conductive pigment paste containing the conductive pigment (B) containing carbon (B-2), the organic solvent (C), and the organic compound (D) having reactivity with the active hydrogen group. We have found that this can be achieved, and have completed the present invention.
That is, the present invention provides the following conductive pigment paste, coating material, conductive coating film and conductive material.

Item 1: Contains a pigment dispersion resin (A) having an active hydrogen group, a conductive pigment (B), an organic solvent (C), and an organic compound (D) having reactivity with an active hydrogen group.
A conductive pigment paste in which the conductive pigment (B) contains carbon nanotubes (B-1) and / or conductive carbon (B-2) having an average primary particle diameter of 10 to 80 nm.
Item 2: The conductive pigment paste according to Item 1, wherein the pigment dispersion resin (A) contains a hydroxyl group as an active hydrogen group.
Item 3: The conductive pigment paste according to Item 2, wherein the pigment dispersion resin (A) has a hydroxyl value of 100 mgKOH / g or more.
Item 4: The conductive pigment paste according to any one of Items 1 to 3, wherein the pigment dispersion resin (A) contains polyvinyl alcohol (a1) and / or modified polyvinyl alcohol (a2).
Item 5: The conductive pigment paste according to Item 3, wherein the degree of saponification of polyvinyl alcohol (a1) and / or modified polyvinyl alcohol (a2) is 85 mol% or more and less than 100 mol%.
Item 6: The conductivity according to any one of Items 1 to 5, wherein the carbon nanotube (B-1) is a multi-walled carbon nanotube having an average outer diameter of 1 nm or more and 25 nm or less and an average length of 0.1 μm or more and 100 μm or less. Pigment paste.
Item 7: Conductive carbon (B-2) having an average primary particle size of 10 to 80 nm is at least one selected from the group consisting of acetylene black, ketjen black, furnace black, thermal black, graphene, and graphite. The conductive pigment paste according to any one of 1 to 6.
Item 8: The solubility parameter δA of the pigment dispersion resin (A) and the solubility parameter δC of the organic solvent (C) have a relationship of 0.6 << | δA-δC | <2.0, Items 1 to 7. The conductive pigment paste according to any one of the above items.
Item 9: At least one selected from the group consisting of an isocyanate compound, an alkoxysilane compound, a compound that reacts with an active hydrogen group to form an acyl group, an epoxy compound, and an ethylenically unsaturated group-containing compound. Item 6. The conductive pigment paste according to any one of Items 1 to 8, which is a species.
Item 10. The conductive pigment paste according to any one of Items 1 to 9, wherein the organic compound (D) has a molecular weight of 1000 or less.
Item 11: The conductivity according to any one of Items 2 to 10, wherein the pigment dispersion resin (A) and the organic compound (D) satisfy the requirement that the rate of change in hydroxyl value measured by the following method is 5% or more. Pigment paste.
<Measurement method of rate of change in hydroxyl value>
In 8.45 g of the organic solvent (C), 0.10 g of the pigment dispersion resin (A) and the organic compound (D) are 2.7 times by mole (270) with respect to the total number of moles of the active hydrogen groups of the pigment dispersion resin (A). %) Add and heat at 100 ° C. for 1 hour. Then, the unreacted organic compound (D) is removed, and the hydroxyl value is measured based on JIS K 0070-1992.
Even when the organic compound (D) is not added as a blank, the measurement is carried out in the same procedure, and the rate of change in hydroxyl value is calculated by the following formula (1).
Rate of change in hydroxyl value = (OHV ⁰ -OHV ^* ) x 100 / OHV ⁰ ... (1)
OHV ⁰ : hydroxyl value when the organic compound (D) is not added OHV ^* : hydroxyl value when the organic compound (D) is added Item 12: The solid content of the pigment dispersion resin (A) is the conductive pigment paste. Items 1 to 11 which are 0.1% by mass or more and 10% by mass or less based on the total solid content of the above, and 0.1% by mass or more and 20% by mass or less based on the content of the conductive pigment (B). The conductive pigment paste according to item 1.
Item 13: The content of the conductive pigment (B) is 50.0% by mass or more and 97.0% by mass or less based on the total solid content of the conductive pigment paste, and is based on the total amount of the conductive pigment paste. Item 2. The conductive pigment paste according to any one of Items 1 to 12, which is 0% by mass or more and 35.0% by mass or less.
Item 14: The reactive functional group concentration of the organic compound (D) is in the range of 1 mol% or more and 50 mol% or less based on the total number of moles of the active hydrogen groups of the pigment dispersion resin (A). 13. The conductive pigment paste according to any one of 13.
Item 15. The conductive pigment paste according to any one of Items 1 to 14, further comprising a film-forming resin (E) having a weight average molecular weight of 100,000 or more and a solubility parameter δD of less than 9.3.
Item 16: A conductive pigment paste containing a pigment dispersion resin (A) having an active hydrogen group, a conductive pigment (B), an organic solvent (C), and an organic compound (D) having reactivity with an active hydrogen group. Is a method of manufacturing
A method for producing a conductive pigment paste, wherein the conductive pigment (B) contains carbon nanotubes (B-1) and / or conductive carbon (B-2) having an average primary particle diameter of 10 to 80 nm.
Item 17: The item is characterized in that the components containing the pigment dispersion resin (A), the conductive pigment (B) and the organic solvent (C) are dispersed and then the organic compound (D) is added and further mixed. 16. The method for producing a conductive pigment paste according to 16.
Item 18: A coating material containing the conductive pigment paste according to any one of Items 1 to 15.
Item 19: The coating material according to Item 18, further containing metal-containing particles having at least one metal element.
Item 20: A method for producing a coating material, wherein metal-containing particles having at least one metal element are added to the conductive pigment paste according to any one of Items 1 to 15.
Item 21: A conductive coating film obtained by applying the coating material according to Item 18 or 19.
Item 22: A conductive material obtained by applying the coating material according to Item 18 or 19 to both surfaces of a plate-shaped base material.

The conductive pigment paste and coating material of the present invention are excellent in pigment dispersibility even at a high pigment concentration, have an appropriate viscosity (low viscosity), are excellent in storage stability, and are excellent in the conductivity of a coating film. Further, the conductive coating film is excellent in finishability and the like.

Hereinafter, embodiments for carrying out the present invention will be described in detail.
It should be noted that the present invention is not limited to the following embodiments, and should be understood to include various modifications implemented without changing the gist of the present invention.

The "coating material" of the present invention is a liquid composition containing a conductive pigment paste.
The "conductive coating film" of the present invention is a solid composition obtained by applying the coating material and drying it.
The "conductive material" of the present invention is obtained by applying the coating material to both surfaces of a plate-shaped base material.
The solubility parameter is also generally called an SP value (solability parameter) and is a measure showing the degree of hydrophilicity or hydrophobicity (polarity) of a solvent or resin. In addition, it is an important measure for determining the solubility and compatibility between the solvent, the resin, and the resin, and when the values of the solubility parameters are close (the absolute value of the difference between the solubility parameters is small), it is general. Solubility and compatibility are good.
In the present invention, first, a conductive pigment paste having a conductive pigment (B) in an appropriate dispersed state is prepared. Further, in order to obtain a coating film satisfying various performances, a coating material or a conductive material is manufactured by adding components such as metal-containing particles to the conductive pigment paste.

[Conductive pigment paste]
The conductive pigment paste of the present invention comprises a pigment dispersion resin (A) having an active hydrogen group, a conductive pigment (B), an organic solvent (C), and an organic compound (D) having reactivity with an active hydrogen group. A conductive pigment paste containing a carbon nanotube (B-1) and / or a conductive carbon (B-2) having an average primary particle diameter of 10 to 80 nm.

<Pigment dispersion resin (A) having an active hydrogen group>
The pigment dispersion resin (A) having an active hydrogen group is not particularly limited as long as it is a resin having an active hydrogen group and having a pigment dispersion action.
Examples of the active hydrogen group include at least one group selected from the group consisting of a hydroxyl group, a primary amino group, a secondary amino group, a carboxyl group, an amide group, a sulfonic acid group, a phosphoric acid group and a silanol group.

The resin is not particularly limited as long as it is a resin other than the film-forming resin (E) having a weight average molecular weight of 100,000 or more and a solubility parameter δD of less than 9.3. For example, acrylic resin, polyester resin, epoxy resin, polyether resin, alkyd resin, urethane resin, polyvinyl alcohol, polyvinyl acetal, polyvinylpyrrolidone, polyvinyl acetate, silicone resin, polycarbonate resin, silicate resin, chlorine resin, and these. Examples include composite resins. These resins may be used alone or in combination of two or more.
Above all, from the viewpoint of imparting sufficient film-forming property to the conductive coating film without deteriorating the excellent conductivity of the conductive coating film formed from the paste or the coating material, the pigment dispersion resin ( As A), it is preferable to contain a vinyl (co) polymer (A-1) obtained by polymerizing or copolymerizing a monomer containing a polymerizable unsaturated group-containing monomer of the following formula (1). The "(co) polymer" of the present invention includes both a polymer obtained by polymerizing one kind of monomer and a copolymer obtained by copolymerizing two or more kinds of monomers.
C (-R) ₂ = C (-R) ₂ ... Equation (1)
[In the above formula, R may be the same or different, and is a hydrogen atom or an organic group. ]

The vinyl (co) polymer (A-1) has a structural unit represented by "-CH ₂ -CH (-X)-" in its structure (wherein X is an active hydrogen group or an active hydrogen group). It is an organic group containing)). Examples of the vinyl (co) polymer (A-1) include a hydroxyl group-containing vinyl (co) polymer, a primary amino group and / or a secondary amino group-containing vinyl (co) polymer, and a carboxyl group-containing vinyl (co) Examples thereof include a co) polymer, an amide group-containing vinyl (co) polymer, a sulfonic acid group-containing vinyl (co) polymer, and a phosphate group-containing vinyl (co) polymer. These (co) polymers can be used alone or in combination of two or more.

Examples of the hydroxyl group-containing vinyl (co) polymer include polyhydroxyethyl (meth) acrylate, polyvinyl alcohol, vinyl alcohol-fatty acid vinyl copolymer, vinyl alcohol-ethylene copolymer, and vinyl alcohol- (N-vinylformamide). Examples thereof include a copolymer, a copolymer of hydroxyethyl (meth) acrylate and another polymerizable unsaturated monomer, and the like. The vinyl alcohol unit in the (co) polymer may be obtained by hydrolyzing the fatty acid vinyl unit after (co) polymerization.
Examples of the amino group-containing vinyl (co) polymer include polyvinylamine, polyallylamine, a copolymer of aminoethyl (meth) acrylate and other polymerizable unsaturated monomer, methylaminoethyl (meth) acrylate and other. Examples thereof include a copolymer with a polymerizable unsaturated monomer.
Examples of the carboxyl group-containing vinyl (co) polymer include a polymer of (meth) acrylic acid, a copolymer of poly (meth) acrylic acid and another polymerizable unsaturated monomer, and the like.
Examples of the amide group-containing vinyl (co) polymer include a polymer of (meth) acrylamide, a copolymer of (meth) acrylamide and another polymerizable unsaturated monomer, and the like.
Examples of the sulfonic acid group-containing vinyl (co) polymer include a polymer such as allylsulfonic acid or styrenesulfonic acid, a copolymer of allylsulfonic acid and / or styrenesulfonic acid and another polymerizable unsaturated monomer, and the like. Can be mentioned.
Examples of the phosphoric acid group-containing vinyl (co) polymer include a polymer of (meth) acryloyloxyalkyl acid phosphate, a copolymer of (meth) acryloyloxyalkyl acid phosphate and another polymerizable unsaturated monomer, and the like. Can be mentioned.

The vinyl (co) polymer (A-1) is a polymerizable unsaturated group that can be copolymerized as needed, in addition to the structural unit represented by "-CH ₂ -CH (-X)-". It may contain a structural unit derived from the contained monomer. Examples of the copolymerizable polymerizable unsaturated group-containing monomer include vinyl formate, vinyl acetate, vinyl propionate, isopropenyl acetate, vinyl valerate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl stearate, and the like. Vinyl acid vinyl ester monomers such as vinyl benzoate, vinyl versatic, vinyl pivalate; olefins such as ethylene, propylene and butylene; aromatic vinyls such as styrene and α-methylstyrene; (meth) acrylic acid Ethnic unsaturated carboxylic acids such as methyl, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dimethyl fumarate, dimethyl maleate, diethyl maleate, diisopropyl itaconate, etc. Alkyl ester monomer; Vinyl ether monomer such as methyl vinyl ether, n-propyl vinyl ether, isobutyl vinyl ether, dodecyl vinyl ether; Ethylene unsaturated nitrile monomer such as (meth) acrylonitrile; Vinyl chloride, vinylidene chloride, vinyl fluoride , Vinyl halide monomer such as vinylidene fluoride or vinylidene monomer; allyl compound such as allyl acetate and allyl chloride; quaternary ammonium group-containing monomer such as 3- (meth) acrylamide propyltrimethylammonium chloride; Examples thereof include vinyltrimethoxysilane, N-vinylformamide, and metaacrylamide. These monomers can be used alone or in combination of two or more.

The polymerization method of the vinyl (co) polymer (A-1) can be produced by a polymerization method known per se, and for example, solution polymerization is preferably used, but the polymerization method is not limited to this, and bulk polymerization is not limited to this. , Emulsion polymerization, suspension polymerization and the like. In the case of solution polymerization, continuous polymerization or batch polymerization may be performed, the monomers may be charged all at once, may be charged separately, or may be added continuously or intermittently.
The polymerization initiator used in the solution polymerization is not particularly limited, but specifically, for example, azobisisobutyronitrile, azobis-2,4-dimethylpaleronitrile, and azobis (4-methoxy-2). , 4-Dimethylpaleronitrile) and other azo compounds; acetyl peroxide, benzoyl peroxide, lauroyl peroxide, acetylcyclohexylsulfonyl peroxide, 2,4,4-trimethylpentyl-2-peroxyphenoxyacetate and the like peroxidation. Substances; Percarbonate compounds such as diisoppilperoxydicarbonate, di-2-ethylhexylperoxydicarbonate, diethoxyethylperoxydicarbonate; t-butylperoxyneodecanate, α-cumylperoxyneodecanate. , T-Butylperoxyneodecanete and other perester compounds; known radical polymerization initiators such as azobisdimethylvaleronitrile and azobismethoxyvaleronitrile can be used.
The polymerization reaction temperature is not particularly limited, but can usually be set in the range of about 30 ° C. or higher and 200 ° C. or lower.

The vinyl (co) polymer (A-1) thus obtained has a degree of polymerization of, for example, 100 or more, preferably 150 or more, for example, 4,000 or less, preferably 3,000 or less, more preferably. Is 700 or less.
The weight average molecular weight is, for example, 1,000 or more, preferably 2,000 or more, more preferably 7,000 or more, and for example, 200,000 or less, preferably 100,000 or less, more preferably 30,000. It is as follows.
The vinyl (co) polymer (A-1) can be made into a solid or a resin solution replaced with an arbitrary solvent by removing the solvent and / or replacing the solvent after the synthesis is completed.
As a method for removing the solvent, it may be carried out by heating at normal pressure or under reduced pressure. As a method of solvent replacement, the replacement solvent may be added at any stage before desolving, during desolving, or after desolving.

In the present invention, it is preferable that the pigment dispersion resin (A) having an active hydrogen group contains a hydroxyl group as an active hydrogen group. The hydroxyl value of the pigment dispersion resin (A) containing a hydroxyl group as an active hydrogen group is, for example, 100 mgKOH / g or more, preferably 300 mgKOH / g or more, more preferably 500 mgKOH / g or more, and for example 2000 mgKOH / g or less, preferably 2000 mgKOH / g or more. It is 1700 mgKOH / g or less, more preferably 1400 mgKOH / g or less.

The pigment dispersion resin (A) having an active hydrogen group preferably contains a hydroxyl group-containing polyvinyl (co) polymer from the viewpoint of improving the pigment dispersibility and reducing the surface resistance of the conductive coating film. , More preferably it contains polyvinyl alcohol (a1) and / or modified polyvinyl alcohol (a2). The degree of saponification of polyvinyl alcohol (a1) and / or modified polyvinyl alcohol (a2) is not particularly limited. For example, it is 70 mol% or more, preferably 80 mol% or more, more preferably 85 mol% or more, for example, 100 mol% (completely saponified product) or less, and preferably less than 100 mol%.

(Solubility parameter δA)
The solubility parameter δA of the pigment dispersion resin (A) is, for example, 9.3 or more, preferably 10.0 or more, more preferably 11. It is 0 or more, for example, 13.5 or less, preferably 13.0 or less, and more preferably 12.5 or less.
The solubility parameter of the resin is numerically quantified based on the turbidity measurement method known to those skilled in the art, and specifically, the formulas of KWSUH and JMCORBETT (Journal of Applied Polymer Science, 12, 2359, It can be obtained according to 1968).
The "solubility parameter δA of the pigment dispersion resin (A)" when there are two or more kinds of pigment dispersion resin (A) is a value obtained by multiplying the solubility parameter value of each resin by the mass fraction.

(Content of pigment dispersion resin (A))
The solid content of the pigment dispersion resin (A) is, for example, 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 1% by mass or more, based on the total solid content of the conductive pigment paste. For example, it is 10% by mass or less, preferably 7.5% by mass or less, and more preferably 5% by mass or less.
The solid content of the pigment dispersion resin (A) is, for example, 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 1% by mass, based on the content of the conductive pigment (B). % Or more, for example, 20% by mass or less, preferably 15% by mass or less, and more preferably 10% by mass or less.

<Conductive pigment (B)>
The conductive pigment (B) contains carbon nanotubes (B-1) and / or conductive carbon (B-2) having an average particle size of 10 to 80 nm. The conductive pigment (B) is further other than the carbon nanotube (B-1), and other conductive pigments (B-3) other than the conductive carbon (B-2) having an average particle size of 10 to 80 nm. May be contained.

(Carbon nanotube (B-1))
As the carbon nanotube (B-1), single-walled carbon nanotubes or multi-walled carbon nanotubes can be used alone or in combination, respectively. In particular, it is preferable to use multi-walled carbon nanotubes in terms of viscosity, conductivity and cost.
The average outer diameter of the carbon nanotube (B-1) is, for example, 1 nm or more, preferably 3 nm or more, more preferably 5 nm or more, and for example, 30 nm or less, preferably 25 nm or less, more preferably 20 nm or less.
The average length of the carbon nanotube (B-1) is, for example, 0.1 μm or more, preferably 1 μm or more, more preferably 5 μm or more, and for example, 100 μm or less, preferably 80 μm or less, more preferably 60 μm or less.
The specific surface area of the carbon nanotube (B-1) is, for example, 1 m ² / g or more, preferably 10 m ² / g or more, and for example 1000 m ² / g or less, more preferably 500 m ² from the relationship of viscosity and conductivity. It is less than / g.

(Conductive carbon (B-2) with an average particle size of 10 to 80 nm)
Examples of the conductive carbon (B-2) having an average primary particle diameter of 10 to 80 nm include at least one conductive carbon selected from the group consisting of acetylene black, ketjen black, furnace black, thermal black, graphene, and graphite. Be done. It is preferably one or more selected from the group consisting of acetylene black, Ketjen black, furnace black, and thermal black, and more preferably one or more selected from the group consisting of acetylene black and Ketjen black. It is preferably one or more of acetylene black. One or more kinds of acetylene black refers to one or more kinds of acetylene black having one or more different physical characteristics such as average primary particle size, BET specific surface area, pH, and DBP oil absorption.
Here, the average primary particle diameter is obtained by observing the conductive carbon (B-2) with an electron microscope, determining the projected area of each of the 100 particles, and determining the diameter when a circle equal to the area is assumed. The average diameter of the primary particles obtained by simply averaging the diameters of 100 particles. If the pigment is in an aggregated state, the calculation is performed using the primary particles constituting the aggregated particles.

The BET specific surface area of the conductive carbon (B-2) is not particularly limited. From the relationship of viscosity and conductivity, for example, 1 m ² / g or more, preferably 10 m ² / g or more, more preferably 20 m ² / g or more, for example, 500 m ² / g or less, preferably 250 m ² / g or less. , More preferably 200 m ² / g or less.
The amount of dibutyl phthalate (DBP) oil absorbed by the conductive carbon (B-2) is not particularly limited. From the relationship of pigment dispersibility and conductivity, it is, for example, 60 ml / 100 g or more, preferably 150 ml / 100 g or more, and for example, 1,000 ml / 100 g or less, preferably 800 ml / 100 g or less.

The conductive carbon (B-2) is preferably in a state in which the primary particles form a chain structure (structure) from the viewpoint of conductivity. The structure index is, for example, 1.5 or more, preferably 1.7 or more, and for example, 4.0 or less, preferably 3.2 or less.
The structure itself can be observed relatively easily even in an image taken with an electron microscope, but the structure index is a numerical value that quantifies the degree of structure. The structure index can generally be defined by the value obtained by dividing the DBP oil absorption amount (ml / 100 g) by the specific surface area (m ² / g). If the structure index is less than 1.5, sufficient conductivity may not be obtained due to the underdeveloped structure. When the structure index exceeds 4.0, the particle size is large with respect to the amount of DBP oil absorbed, so that the conductive path is reduced and sufficient conductivity may not be exhibited, or the viscosity of the paste may be increased.

(Other conductive pigments (B-3))
The conductive pigment (B) may contain another conductive pigment (B-3). The other conductive pigment (B-3) is a conductive pigment other than the carbon nanotube (B-1), and is a conductive pigment other than the conductive carbon (B-2) having an average particle diameter of 10 to 80 nm. ..
Examples of the other conductive pigment (B-3) include one or more selected from the group consisting of metal powders, metal fibers, metal compounds, conductive ceramics and the like. Here, examples of the metal in the metal powder, the metal fiber, the metal compound, and the like include one or more metal elements selected from the group consisting of copper, silver, gold, nickel, aluminum, titanium, and the like.
Specifically, metal powders such as copper, silver, gold, nickel, aluminum and titanium; metal compounds doped with various elements such as antimony-doped tin oxide and phosphorus-doped tin oxide; surface with antimony and / or antimony. Coated needle-shaped titanium oxide, antimony oxide, zinc antimony, indium tin oxide, a pigment coated with tin oxide on the whisker surface of carbon or graphite, tin oxide, antimony-doped tin oxide, tin-doped on the flake-shaped mica surface. Coating pigments such as pigments coated with at least one conductive metal oxide selected from the group consisting of indium oxide (ITO), fluorine-doped tin oxide (FTO), phosphorus-doped tin oxide and nickel oxide; oxidation on the surface of titanium dioxide particles. One or more selected from the group consisting of conductive pigments containing tin and phosphorus; and the like can be mentioned.

The shape of the other conductive pigment (B-3) is not particularly limited. For example, there are various shapes such as particles, flakes, and fibers (including whiskers).
The aspect ratio of the other conductive pigment (B-3) is not particularly limited. For example, a shape having a high aspect ratio such as a plate shape, a needle shape, a fibrous shape, or a rod shape is preferable. Among them, the aspect ratio of the primary particles is preferably 1.3 or more, more preferably 1.5 or more, further preferably 2.0 or more, and preferably 5.0 or more. Especially preferable.
Here, the aspect ratio is the ratio of the longest dimension to the shortest dimension of the three-dimensional body. As a method for measuring the aspect ratio, for example, 100 images of pigment particles taken by a scanning electron microscope (SEM) are arbitrarily selected, and the length ratio is calculated by image analysis and averaged.
When the shape of the other conductive pigment (B-3) is fibrous, the average fiber diameter is, for example, 1 nm or more, preferably 10 nm or more, more preferably 50 nm or more, for example, 1000 nm, due to the relationship between viscosity and conductivity. Hereinafter, it is preferably 500 nm or less, more preferably 250 nm or less. The average fiber length is, for example, 0.1 μm or more, preferably 1 μm or more, more preferably 5 μm or more, and for example, 50 μm or less, preferably 30 μm or less, more preferably 20 μm or less, from the relationship of viscosity and conductivity.
When the shape of the other conductive pigment (B-3) is other than fibrous, the average particle size (D50) is, for example, 20 nm or more, preferably 33 nm or more, from the relationship of viscosity and conductivity. For example, it is 100 nm or less, preferably 70 nm or less. Here, the average particle size (D50) is a value measured by using a microtrack particle size distribution measuring device (MT3300, manufactured by Nikkiso Co., Ltd.).

(Composition of Conductive Pigment (B))
The composition of the conductive pigment (B) is not particularly limited, and is not particularly limited.
(I) Those composed only of carbon nanotubes (B-1),
(Ii) Consists of only conductive carbon (B-2),
(Iii) Composed of carbon nanotubes (B-1) and conductive carbon (B-2),
(Iv) Composed of carbon nanotubes (B-1) and other conductive pigments (B-3),
(V) Composed of conductive carbon (B-2) and other conductive pigments (B-3),
(Vi) Composed of carbon nanotubes (B-1), conductive carbon (B-2) and other conductive pigments (B-3),
Either may be used.
In the case of (iii), the solid content ratio of the carbon nanotube (B-1) and the conductive carbon (B-2) is preferably 1 / of the carbon nanotube (B-1) / conductive carbon (B-2). It is in the range of 99 to 99/1.
In the case of (iv), the solid content ratio of the carbon nanotube (B-1) and the other conductive pigment (B-3) is preferably carbon nanotube (B-1) / other conductive pigment (B-3). ) Is in the range of 1/99 to 99/1.
In the case of (v), the solid content ratio of the conductive carbon (B-2) and the other conductive pigment (B-3) is preferably conductive carbon (B-2) / other conductive pigment (B). -3) is in the range of 1/99 to 99/1.
In the case of (vi), the solid content ratio of the carbon nanotube (B-1), the conductive carbon (B-2) and the other conductive pigment (B-3) is preferably carbon nanotube (B-1) /. The conductive carbon (B-2) / other conductive pigment (B-3) is in the range of 1/1/98 to 1/98/1 to 1/1/98.

(Content of Conductive Pigment (B))
The solid content of the conductive pigment (B) is, for example, 50.0% by mass or more, preferably 55.0% by mass, based on the total solid content of the conductive pigment paste from the viewpoint of conductivity and pigment dispersibility. As described above, it is more preferably 65.0% by mass or more, for example, 99.0% by mass or less, preferably 98.0% by mass or less, and more preferably 97.0% by mass or less.
When the conductive pigment (B) contains the carbon nanotube (B-1), the solid content of the conductive pigment (B) is, for example, 50.0% by mass or more based on the total solid content of the conductive pigment paste. It is preferably 55.0% by mass or more, more preferably 65.0% by mass or more, for example, 95.0% by mass or less, preferably 90.0% by mass or less, and more preferably 85.0% by mass or less. ..
When the conductive pigment (B) contains the conductive carbon (B-2), the solid content of the conductive pigment (B) is, for example, 60.0% by mass based on the total solid content of the conductive pigment paste. As described above, it is preferably 64.0% by mass or more, more preferably 68.0% by mass or more, for example, 99.0% by mass or less, preferably 98.0% by mass or less, and more preferably 97.0% by mass or less. be.

<Organic solvent (C)>
The organic solvent (C) used in the conductive pigment paste of the present invention is not particularly limited as long as it has compatibility with the pigment dispersion resin (A) and can disperse the conductive pigment (B). Specifically, for example, hydrocarbon solvents such as n-butane, n-hexane, n-heptane, n-octane, cyclopentane, cyclohexane, cyclobutane; aromatic solvents such as toluene and xylene; methylisobutylketone and the like. Ketone-based solvents; ether-based solvents such as n-butyl ether, dioxane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol; ethyl acetate, n-butyl acetate, isobutyl acetate. , Ethethylene glycol monomethyl ether acetate, butyl carbitol acetate and other ester solvents; methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone and other ketone solvents; ethanol, isopropanol, n-butanol, sec-butanol, isobutanol and the like alcohols. Solvents: Equamid (trade name, manufactured by Idemitsu Kosan Co., Ltd., amide solvent), N, N-dimethylformamide, N, N-dimethylacetamide, N-methylformamide, N-methylacetamide, N-methylpropioamide, N Examples thereof include amide-based solvents such as -methyl-2-pyrrolidone, and among them, N-methyl-2-pyrrolidone is preferable. These solvents may be used alone or in combination of two or more.

The solvent (C) that can be used in the conductive pigment paste of the present invention includes a hydroxyl group, a carboxyl group, and the like from the viewpoint of the solubility of the pigment dispersion resin (A) having an active hydrogen group and the storage stability of the conductive pigment paste. It is preferable to contain a solvent having a polar functional group such as an amide group, an amino group and an ether group.
Further, from the viewpoint of the pigment dispersibility of the conductive pigment paste and the viewpoint of not deteriorating or hydrolyzing the resin component, it is preferable that the conductive pigment paste does not contain water substantially. Here, "substantially water-free" means that the content of water is usually 1% by mass or less, preferably 0.5% by mass or less, particularly based on the total amount of the conductive pigment paste. It means that it is preferably 0.1% by mass or less.
In the present invention, the water content of the conductive pigment paste can be measured by the Karl Fischer titration method. Specifically, using a Karl Fischer titer (Kyoto Electronics Manufacturing Co., Ltd., product name: MKC-610), setting the water vaporizer (Kyoto Electronics Manufacturing Co., Ltd., product name ADP-611) provided in the device. The temperature can be measured as 130 ° C.

Further, from the viewpoint of the solubility of the pigment dispersion resin (A) having an active hydrogen group and the storage stability of the conductive pigment paste, the solubility parameter (SP value) of the solvent (C) is 10.0 (cal / cm). ³ ) It is preferably ^1/2 or more, for example 10.4 (cal / cm ³ ) ^1/2 or more, preferably 10.5 (cal / cm ³ ) ^1/2 or more, for example 15.0 ( cal / cm ³ ) ^1/2 or less, preferably 13.0 (cal / cm ³ ) ^1/2 or less.

Solvent solubility parameters can be determined according to the method described in J. Brandrup and EHImmergut, "Polymer Handbook" VII Solubility Parament Values, pp519-559 (John Wiley & Sons, 3rd Edition, 1989). When two or more kinds of solvents are used in combination as a mixed solvent, the solubility parameter of the mixed solvent can be obtained experimentally, and as a simple method, the mole fraction and the solubility parameter of each liquid solvent are used. It can also be calculated by the sum of the products of and.
The "solubility parameter of the solvent (C)" of the present invention is a solubility parameter of all the solvents (mixed solvents) contained in the conductive pigment paste.

The content of the organic solvent (C) is, for example, 40% by mass or more, preferably 50% by mass or more, more preferably 60% by mass or more, and preferably 95% by mass or less, preferably 95% by mass or more, based on the total amount of the conductive pigment paste. Is 90% by mass or less, more preferably 85% by mass or less.

<Organic compound (D) having reactivity with active hydrogen group>
The organic compound (D) having reactivity with an active hydrogen group used in the conductive pigment paste of the present invention is not particularly limited as long as it is an organic compound having one or more groups having reactivity with an active hydrogen group.
The conductive paste prepared by using the pigment dispersion resin (A) having an active hydrogen group, the conductive pigment (B), and the organic solvent (C) has good dispersibility, but insufficient viscosity stability over time. Is. In particular, the higher the functional group concentration of the active hydrogen group in the pigment dispersion resin (A) having an active hydrogen group, the more remarkable this tendency. It is presumed that this is because the active hydrogen groups contribute to the dispersion of the pigment, while the pigment dispersion resins (A) form a network with each other due to hydrogen bonds or the like. Therefore, the pigment dispersion resin (A) is formed by adding an organic compound (D) having reactivity with an active hydrogen group to a conductive paste and reacting the active hydrogen group with a group having reactivity with an active hydrogen group. It is speculated that the interaction between them is reduced and the stability over time is improved. The present invention is not limited to this guess.

Examples of the group having reactivity with the active hydrogen group include an isocyanate group, an alkoxysilane group, a carboxyl group, a carboxylic acid halide group, a carboxylic acid hydride group, an epoxy group, an aziridinyl group, an oxazoline group, a carbodiimide group and an aldehyde group. It is selected from the group consisting of an ethylenically unsaturated group (vinyl group, α, β unsaturated carbonyl group (for example, (meth) acryloyloxy group, (meth) acrylamide group, unsaturated carbonyl group, etc.), allyl group, etc.) and the like. One or more types can be mentioned.
Examples of the organic compound (D) having reactivity with an active hydrogen group include an isocyanate compound, an alkoxysilane compound, a compound that reacts with an active hydrogen group to form an acyl group, an epoxy compound, and an ethylenically unsaturated group. It is preferably at least one selected from the group consisting of compounds.

The molecular weight of the organic compound (D) having reactivity with an active hydrogen group is not particularly limited, but is, for example, 1000 or less, preferably 800 or less, more preferably 600 or less, for example, 10 or more, preferably 50 or more, and more. It is preferably 100 or more.
The organic compound (D) having reactivity with an active hydrogen group reacts in the paste with a pigment dispersion resin (A) having a part thereof having an active hydrogen group. After that, when the conductive pigment paste or the coating material is applied and the solvent is removed by heat drying or the like, the unreacted substance of the organic compound (D) does not remain in the conductive coating film or the conductive material as much as possible. Is preferable.

(Isocyanate compound)
The isocyanate compound is not particularly limited as long as it is a compound having one or more isocyanate groups. For example, one or more selected from the group consisting of monoisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic aliphatic polyisocyanate, aromatic polyisocyanate, and derivatives thereof can be mentioned.

Examples of the monoisocyanate include methyl isocyanate, ethyl isocyanate, propyl isocyanate, n-butyl monoisocyanate, n-hexyl monoisocyanate, n-hexadecyl monoisocyanate, n-octadecyl monoisocyanate, p-isopropylphenyl monoisocyanate, p-. One or more selected from the group consisting of benzyloxyphenyl monoisocyanate, additive TI (manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name) and the like can be mentioned.

Examples of the aliphatic polyisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butyrenized isocyanate, 2,3-butyrenis diisocyanate, and 1,3-. An aliphatic diisocyanate such as butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisosocyanatomethyl caproate, for example, lysine ester triisocyanate, 1,4,8- Triisosianatooctane, 1,6,11-triisosyanatoundecane, 1,8-diisosyanato-4-isosyanatomethyloctane, 1,3,6-triisosyanatohexane, 2,5,7-trimethyl-1, One or more species selected from the group consisting of aliphatic triisocyanates such as 8-diisosyanato-5-isosyanatomethyl octane and the like can be mentioned.

Examples of the alicyclic polyisocyanate include 1,3-cyclopentenediisocyanate, 1,4-cyclohexanediisocyanate, 1,3-cyclohexanediisocyanate, and 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate (common name:: Isophoron diisocyanate), 4,4'-methylenebis (cyclohexylisocyanate), methyl-2,4-cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate, 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane ( Conventional name: hydrogenated xylylene diisocyanate) or a mixture thereof, alicyclic diisocyanate such as norbornan diisocyanate, for example, 1,3,5-triisocyanatocyclohexane, 1,3,5-trimethylisocyanatocyclohexane, 2- (3). -Isocyanatopropyl) -2,5-di (isocyanatomethyl) -bicyclo (2.2.1) heptane, 2- (3-isocyanatopropyl) -2,6-di (isocyanatomethyl) -bicyclo ( 2.2.1) Heptane, 3- (3-isocyanatopropyl) -2,5-di (isocyanatomethyl) -bicyclo (2.2.1) heptane, 5- (2-isocyanatoethyl) -2 -Isocyanatomethyl-3- (3-isocyanatopropyl) -bicyclo (2.2.1) heptane, 6- (2-isocyanatoethyl) -2-isocyanatomethyl-3- (3-isocyanatopropyl) -Bicyclo (2.2.1) heptane, 5- (2-isocyanatoethyl) -2-isocyanatomethyl-2- (3-isocyanatopropyl) -bicyclo (2.2.1) -heptane, 6- (2-Isocyanatoethyl) -2-Isocyanatomethyl-2- (3-Isocyanatopropyl) -bicyclo (2.2.1) One or more selected from the group consisting of alicyclic triisocyanates such as heptane. Can be mentioned.

Examples of the aromatic aliphatic polyisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω, ω'-diisocyanato-1,4-diethylbenzene, 1,3- or 1,4-bis (1,3- or 1,4-bis). Arophilic aliphatic diisocyanate such as 1-isocyanato-1-methylethyl) benzene (common name: tetramethylxylylene diisocyanate) or a mixture thereof, for example, aromatic aliphatic triisocyanate such as 1,3,5-triisocyanatomethylbenzene. One or more species selected from the group consisting of the above can be mentioned.

Examples of the aromatic polyisocyanate include m-phenylenedi isocyanate, p-phenylenedi isocyanate, 4,4'-diphenyldiisocyanate, 1,5-naphthalenediisocyanate, 2,4'-or 4,4'-diphenylmethane diisocyanate or a mixture thereof. , 2,4- or 2,6-tolylene diisocyanate or a mixture thereof, aromatic diisocyanates such as 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate, for example, triphenylmethane-4,4', 4 ''-Aromatic triisocyanates such as triisocyanate, 1,3,5-triisocyanatobenzene, 2,4,6-triisocyanatotoluene, such as diphenylmethane-2,2', 5,5'-tetraisocyanate. One or more selected from the group consisting of aromatic tetraisocyanates and the like.

Examples of the isocyanate derivative include dimer, trimer, biuret, allophanate, carbodiimide, uretdione, uretoimine, isocyanurate, oxadiazine trione, polymethylene polyphenyl polyisocyanate (crude MDI, polypeptide MDI) and crude TDI of polyisocyanate compounds. One or more species selected from the group consisting of the above can be mentioned.

In the present invention, the isocyanate compound is preferably monoisocyanate from the viewpoint of reaction control and the like.

(Alkoxysilane compound)
The alkoxysilane compound is not particularly limited as long as it is a silane compound having one or more alkoxy groups. for example,
Formula (I): Ra Si (OR') _{4-a (} In the formula, R is an organic group, R'is an alkyl group having 1 to 6 carbon atoms, and a is 0, 1, 2 or 3).
Alkoxysilane compound represented by, and
Formula (II): (R'O) _3-b R _b Si-R''-SiR _c (OR') _3-c (In the formula, R is an organic group and R'is an alkyl having 1 to 6 carbon atoms. Group, R'' is a divalent organic group having 1 to 20 carbon atoms, and b is 0, 1 or 2).
One or more selected from the group consisting of the bisalkoxysilane compound represented by.

Examples of the alkoxysilane compound represented by the formula (I) include one or more selected from the group consisting of tetraalkoxysilane, alkyltrialkoxysilane, dialkyldialkoxysilane, and trialkylalkoxysilane.
For example, one or more tetraalkoxysilanes selected from the group consisting of tetramethoxysilanes, tetraethoxysilanes, etc .; for example, methyltrimethoxysilanes, methyltrimethoxysilanes, ethyltrimethoxysilanes, methyltriethoxysilanes, ethyltriethoxysilanes. One or more alkyltrialkoxysilanes selected from the group consisting of, for example, dimethyldimethoxysilane, dimethyldimethoxysilane, diethyldimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, etc. Dialkyldialkoxysilane; one or more trialkylalkoxysilanes selected from the group consisting of trimethylmethoxysilane, trimethylmethoxysilane, triethylmethoxysilane, trimethylethoxysilane, triethylethoxysilane, etc .; Can be mentioned.

Examples of the alkoxysilane compound represented by the formula (II) include 1,6-bis (trimethoxysilyl) hexane, 1,7-bis (trimethoxysilyl) heptane, and 1,8-bis (trimethoxysilyl). One or more bis (alkoxysilyl) alkanes selected from the group consisting of octane and the like; one selected from the group consisting of 1,4-bis (alkoxysilyl) benzene, 1,4-bis (alkoxysilylalkyl) benzene and the like. The above aromatic compounds; one or more alkylene oxide compounds selected from the group consisting of 1,2-bis (alkoxysilyl) ethylene oxide, 1,3-bis (alkoxysilyl) propylene oxide and the like; 1,3-bis (alkoxysilyl) One or more fats selected from the group consisting of silyl) cyclobutane, 1,3-bis (alkoxysilylalkyl) cyclobutane, 1,4-bis (alkoxysilyl) cyclohexane, 1,4-bis (alkoxysilylalkyl) cyclohexane and the like. Cyclic compounds and the like can be mentioned.

(Compound that reacts with an active hydrogen group to form an acyl group)
Examples of the compound that reacts with an active hydrogen group to form an acyl group include compounds known as acylating agents in the field of organic chemistry.
For example, one or more selected from the group consisting of a carboxylic acid halide compound, a carboxylic acid umhydride compound, and a ketene compound can be mentioned.
The carboxylic acid forming the carboxylic acid halide compound or the carboxylic acid umhydride compound is not particularly limited. For example, one or more selected from the group consisting of carboxylic acids having 1 to 20 carbon atoms (formic acid, acetic acid, propionic acid, glutamic acid, benzoic acid, maleic acid, phthalic acid, etc.) can be mentioned.
Examples of the ketene compound include one or more selected from the group consisting of ketene, diketene, aldehyde ketene and ketene.

(Epoxy compound)
The epoxy compound is not particularly limited as long as it is a compound having one or more epoxy groups (glycidyl groups) in the molecule.
For example, one or more selected from the group consisting of epoxy group-containing compounds such as neopentyl glycol diglycidyl ether, trimethylolpropane polyglycidyl ether, and bisphenol-based epoxy resin can be mentioned.

(Ethylene unsaturated group-containing compound)
Examples of the ethylenically unsaturated compound include a vinyl group, an α, β unsaturated carbonyl group (for example, a (meth) acryloyloxy group, a (meth) acrylamide group, an unsaturated carbonyl group, etc.), an allyl group, and the like. Examples include compounds having a saturated group.

Examples of the ethylenically unsaturated compound include styrene compounds such as styrene, vinyltoluene, chlorostyrene, (o, m, p-) hydroxystyrene, α-methylstyrene, styrenesulfonic acid, and divinylbenzene; vinyl acetate, N. -Vinylpyrrolidone, 2-vinylpyridine, N-vinylcaprolactum, cyclohexylvinyl ether, 2-hydroxyethylvinyl ether, 4-hydroxybutylvinyl ether, 1,4-cyclohexanedimethanol monovinyl ether, diethylene glycol monovinyl ether, dipropylene glycol monovinyl ether, acetoxy Vinyl compounds such as ethyl vinyl ether, acetoxybutyl vinyl ether, acetylcyclohexanedimethanol monovinyl ether, acetyldiethylene glycol monovinyl ether, glycidyloxyethyl vinyl ether, glycidyloxybutylvinyl ether, glycidylcyclohexanedimethanol monovinyl ether and glycidyldiethylene glycol monovinyl ether; Meta) acrylate, ethyl (meth) acrylate, acrylonitrile, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, phenoxyethyl (meth) acrylate, glycidyl (meth) Acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, n-butyl (meth) acrylate, hexyl (meth) acrylate , Octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, n-stearyl (meth) acrylate, benzyl (meth) acrylate, 2- (meth) acryloyloxyethyl acid phosphate, furfuryl (meth) acrylate, Carbitol (meth) acrylate, butoxyethyl (meth) acrylate, allyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate , Dipropylene glycol di (meth) acrylate, Polypropylene glycol di (meth) acrylate , Butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide-modified bisphenol A type di (meth) acrylate, propylene oxide-modified bisphenol A type di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate. , Ethylated cyclohexanedimethanol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethyl propantri (meth) acrylate, pentaerythritol Tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol penta (meth) acrylate, ethylene oxide-modified dipentaerythritol penta (Meta) acrylate compounds such as (meth) acrylates and ethoxylated glycerin triacrylates; (meth) acrylamide, (meth) acryloylmorpholine, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide. , N-Hydroxyethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-methyl (meth) acrylamide, N-methylol (meth) acrylamide and other (meth) acrylamide compounds; acrylic acid, maleic acid, fumaric acid , An unsaturated carboxylic acid compound such as maleic anhydride, N-phenylmaleimide, N-hydroxyethylmaleimide, N-hydroxyethylcitracoimide or a modified product thereof; allyl alcohol, diallyl ether, allyl halide, allyl sulfonic acid, etc. An allyl-based compound; one or more selected from the group consisting of the above, and the like.

(Carbodiimide compound, aziridinyl group-containing compound, oxazoline compound)
The organic compound (D) having reactivity with an active hydrogen group may be one or more selected from the group consisting of a carbodiimide compound, an aziridinyl group-containing compound, an oxazoline compound and the like.
Examples of the carbodiimide compound include one or more selected from the group consisting of dicyclohexylcarposiimide, diisopropylcarposiimide, polycarbodiimide compound (manufactured by Nisshinbo Chemical Co., Ltd., trade name: carbodilite) and the like.
Examples of the aziridinyl group-containing compound include trimethylolpropane tris (2-aziridinyl propionate), 1.1'-(4-methyl-m-phenylene) -bis-3-3-aziridinyl urea, 1. One or more selected from the group consisting of 1'-(hexamethylene) -bis-3,3-aziridinyl urea, ethylene bis (2-aziridinyl propionate) and the like can be mentioned.
Examples of the oxazoline compound include one or more selected from the group consisting of oxazoline, bisoxazoline compound, oxazoline group-containing polymer (manufactured by Nippon Shokubai Co., Ltd., trade name Epocross) and the like.

The solid content of the organic compound (D) having reactivity with the active hydrogen group is, for example, 0.10% by mass or more based on the total solid content of the conductive pigment paste from the viewpoint of conductivity and pigment dispersibility. It is preferably 0.20% by mass or more, more preferably 0.30% by mass or more, for example, 1.0% by mass or less, preferably 0.80% by mass or less, and more preferably 0.60% by mass or less. ..
Further, the concentration of the reactive functional group of the organic compound (D) is, for example, 1 mol% or more, preferably 5 mol% or more, more preferably 10 based on the total number of moles of the active hydrogen groups of the pigment dispersion resin (A). It is mol% or more, for example, 50 mol% or less, preferably 30 mol% or less, and more preferably 20 mol% or less.

<Film forming resin (E)>
The conductive pigment paste of the present invention may further contain a film-forming resin (E) having a weight average molecular weight of 100,000 or more and a solubility parameter δD of less than 9.3. The film-forming resin (E) is a resin that satisfies the requirements related to the weight average molecular weight and the solubility parameter, is different from the pigment dispersion resin (A), and is a low-polarity resin that does not substantially contain an active hydrogen group. If there is, there is no particular limitation. The concentration of active hydrogen groups in the film-forming resin (E) is, for example, less than 10 mmol / g, preferably less than 5 mmol / g, and more preferably less than 1 mmol / g.
Examples of the film-forming resin (E) include acrylic resin, polyester resin, epoxy resin, polyether resin, alkyd resin, urethane resin, silicone resin, polycarbonate resin, chlorine-based resin, fluororesin, polyvinylpyrrolidone resin, and polyvinyl acetal. Examples thereof include resins and composite resins thereof. These resins may be used alone or in combination of two or more.
In the present invention, a fluororesin is preferable, and one type can be used alone or two or more types can be used in combination. In particular, one or more of polyvinylidene fluoride (PVDF) is preferable.
The film-forming resin (E) is a component that contributes to film formation when a conductive coating film or a conductive material is formed by using a conductive pigment paste.

The weight average molecular weight of the film-forming resin (E) is not particularly limited. From the viewpoint of adhesion to the substrate, reinforcement of the physical characteristics of the coating film, and solvent resistance, for example, 100,000 or more, preferably 500,000 or more, more preferably 650,000 or more, for example, 3 million or less. Yes, preferably 2 million or less.
The solubility parameter of the film-forming resin (E) is preferably less than 10, and more preferably less than 9.3.

The solid content of the film-forming resin (E) is, for example, 1% by mass or more, preferably 10% by mass or more, more preferably, based on the total solid content of the conductive pigment paste from the viewpoint of conductivity and pigment dispersibility. Is 15% by mass or more, for example, 60% by mass or less, preferably 50% by mass or less, and more preferably 40% by mass or less.

<Other ingredients (F)>
The conductive pigment paste of the present invention comprises a pigment dispersion resin (A) having active hydrogen, a conductive pigment (B), an organic solvent (C), an organic compound (D) having reactivity with an active hydrogen group, and a film forming. In addition to the resin (E), other components (F) may be contained, if necessary.
Other components (F) include resins other than the pigment dispersion resin (A) and the film-forming resin (E), pH adjusters, neutralizers, defoamers, preservatives, rust inhibitors, plasticizers, and conductive materials. Pigments other than the pigment (B) can be mentioned.

Examples of pigments other than the conductive pigment (B) include white pigments such as titanium white and zinc flower; blue pigments such as cyanine blue and induslen blue; green pigments such as cyanine green and green blue; azo-based and quinacridone-based pigments. Organic red pigments, red pigments such as red iron oxide; organic yellow pigments such as benzimidazolone-based, isoindolinone-based, isoindolin-based and quinophthalone-based, and yellow pigments such as titanium yellow and yellow lead. These pigments can be used alone or in combination of two or more. Pigments other than these conductive pigments (B) can be used for the purpose of color adjustment, reinforcement of the physical properties of the film, etc. within a range that does not significantly impair the conductivity, and the pigment dispersion resin (A) and the conductive pigment ( It may be dispersed together with B) at the same time, or the pigment dispersion resin (A) and the conductive pigment (B) may be dispersed to prepare a paste and then mixed as a pigment or a pigment paste.
The content of the pigment other than the conductive pigment (B) and the carbon nanotube (F) is preferably 10% by mass or less, more preferably 5% by mass or less, based on all the pigments in the conductive pigment paste. It is more preferably mass% or less, and particularly preferably not substantially contained.

<Characteristics of conductive pigment paste, etc.>
(SP value difference)
In the conductive pigment paste of the present invention, the absolute value | δA-δC | of the difference between the solubility parameter δA of the pigment dispersion resin (A) and the solubility parameter δC of the organic solvent (C) exceeds, for example, 0.8. It is preferably more than 0.6, for example, less than 2.5, preferably less than 2.0. As a result, the solubility of the pigment dispersion resin (A) in the organic solvent becomes good, and the dispersibility and storage stability can be improved.
Further, when the conductive pigment paste of the present invention contains the film-forming resin (E), the absolute value of the difference between the solubility parameter δE of the film-forming resin (E) and the solubility parameter δC of the solvent (C) | -ΔC | is, for example, less than 3.0, preferably 0 or more, more preferably 0.1 or more, preferably 2.8 or less, and more preferably 2.5 or less. As a result, the solubility of the film-forming resin (E) in the organic solvent becomes good, and the dispersibility and storage stability can be improved.

(Rate of change in hydroxyl value)
In the conductive pigment paste of the present invention, the pigment dispersion resin (A) and the organic compound (D) preferably satisfy the requirement that the rate of change in hydroxyl value measured by the following method is 5% or more. It is more preferably 15% or more, further preferably 25% or more, still more preferably 100% or less, still more preferably 95% or less.
<Measurement method of rate of change in hydroxyl value>
In 8.45 g of the organic solvent (C), 0.10 g of the pigment dispersion resin (A) and the organic compound (D) are 2.7 times by mole (270) with respect to the total number of moles of the active hydrogen groups of the pigment dispersion resin (A). %) Add and heat at 100 ° C. for 1 hour. Then, the unreacted organic compound (D) is removed, and the hydroxyl value is measured based on JIS K 0070-1992.
Even when the organic compound (D) is not added as a blank, the measurement is carried out in the same procedure, and the rate of change in hydroxyl value is calculated by the following formula (1).
Rate of change in hydroxyl value = (OHV ⁰ -OHV ^* ) x 100 / OHV ⁰ ... (1)
OHV ⁰ : Hydroxyl value when the organic compound (D) is not added OHV ^* : Hydroxyl value when the organic compound (D) is added OHV *: Hydroxyl value when the organic compound (D) is added

(viscosity)
From the viewpoint of pigment dispersibility and storage stability, the viscosity of the conductive pigment paste of the present invention is, for example, less than 5000 mPa · s, preferably 10 mPa · s or more at a shear rate of 0.1 s ^-1 . It is more preferably 50 mPa · s or more, further preferably 100 mPa · s or more, preferably less than 5000 mPa · s, more preferably less than 2500 mPa · s, still more preferably less than 1000 mPa · s.
The viscosity can be measured using, for example, a cone & plate type viscometer (manufactured by HAAKE, trade name Mars 2, diameter 35 mm, cone & plate inclined at 2 °).

[Method for producing conductive pigment paste]
The method for producing the conductive pigment paste of the present invention is not particularly limited. Pigment dispersion resin (A) having an active hydrogen group, carbon nanotube (B-1) and / or conductive pigment (B) containing conductive carbon (B-2) having an average primary particle diameter of 10 to 80 nm, organic. The solvent (C), the organic compound (D) having reactivity with the active hydrogen group, the film-forming resin (E) if necessary, and other components (F) if necessary are mixed simultaneously or in any order. Therefore, it is preferable to provide a step of performing dispersion processing.
For example, a method may be mentioned in which a component containing a pigment dispersion resin (A), a conductive pigment (B) and an organic solvent (C) is dispersed and then the organic compound (D) is added and further mixed. In this case, the active hydrogen groups can be efficiently dispersed in a state where the amount of active hydrogen groups is large, and the active hydrogen groups that do not contribute to the dispersion after the dispersion react with the organic compound (D) to reduce the interaction between the resins and the viscosity with time. This is especially preferred because it improves stability.
For example, a pigment dispersion resin (A) having an active hydrogen group, a conductive pigment (B) containing a carbon nanotube (B-1), an organic solvent (C), and an organic compound having reactivity with an active hydrogen group ( D) is mixed simultaneously or in any order and dispersed to form a carbon nanotube dispersion liquid, a pigment dispersion resin (A) having an active hydrogen group, and conductivity having an average primary particle diameter of 10 to 80 nm. The conductive pigment (B) containing carbon (B-2), the organic solvent (C), and the organic compound (D) having reactivity with the active hydrogen group are mixed simultaneously or in any order to disperse the treatment. A method including a step of obtaining a conductive carbon dispersion liquid and a step of mixing the carbon nanotube dispersion liquid and the conductive carbon dispersion liquid can be mentioned.

In the production of the conductive pigment paste, each component contained in the conductive pigment paste is, for example, a dispenser, a paint shaker, a sand mill, a ball mill, a pebble mill, an LMZ mill, a DCP pearl mill, a planetary ball mill, a homogenizer, a twin-screw kneader, and a thin film. It is preferable to have a step of uniformly mixing or dispersing using a stirrer or a disperser such as a swirl type high-speed mixer (trade name: Claire mix, fill mix, etc.).

[Coating material / Manufacturing method of coating material]
<Coating material>
The coating material of the present invention contains the above-mentioned conductive pigment paste. Preferably, it further contains metal-containing particles having at least one metal element. If necessary, the coating material of the present invention may further contain the components described in <Other components (F)> in the above [conductive pigment paste].

(Metal-containing particles)
The metal-containing particles that may be contained in the coating material of the present invention are mixed with the conductive pigment paste in the manufacturing process of the coating material, and are contained in the above-mentioned conductive pigment paste. It is different from B). Further, the metal-containing particles are preferably metal-containing particles having at least one metal element from the viewpoint of the conductivity of the conductive coating film, the physical properties of the coating film, and the like, and among them, Fe, Cu, Mn, and the like. It preferably contains metal-containing particles having at least one transition metal element selected from Ni, Zr, Zn, Mo, Ag, Au, Pt, Ti, Cr and Mo. The metal element preferably contains a metal element having an electric conductivity (20 ° C.) of 9 × 10 ⁶ S / m or more, more preferably 12 × 10 ⁶ S / m or more, and 14 × 10 ⁶ S / m or more is more preferable.
The metal-containing particles may be a metal having one kind of metal element or a composite metal having a plurality of metal elements, and are preferably used in these nitrides, oxides, sulfides, and / or hydroxides. be able to.

As the average particle size of the metal-containing particles, the average particle size (D50) obtained by diluting the coating material with a solvent and measuring the particle size distribution based on the volume by the laser diffraction / scattering method is preferably 1,501 nm or more, for example. It is 1,600 nm or more, preferably 2,000 nm or more, for example, 50,000 nm or less, preferably 30,000 nm or less.
The content of the metal-containing particles in the coating material is usually 10% by mass or more and 99% by mass or less, preferably 15% by mass or more and 95% by mass or less, based on the total solid content in the coating material. It is preferable from the viewpoint of conductivity, physical properties of the coating film, and the like.
The content of the pigment dispersion resin (A) in the coating material is not particularly limited. From the viewpoint of viscosity at the time of pigment dispersion, pigment dispersibility, storage stability, production efficiency, conductivity, etc., for example, 0.01% by mass or more, preferably 0.02, based on the total amount of solid content in the coating material. By mass or more, more preferably 0.05% by mass or more, still more preferably 0.08% by mass or more, for example, 80% by mass or less, preferably 50% by mass or less, more preferably 20% by mass or less, still more preferably. It is 10% by mass or less.
The content of the pigment dispersion resin (A) with respect to 100 parts by mass of the conductive pigment (B) is, for example, 0.01 part by mass or more, preferably 0.02 part by mass or more, more preferably 0, based on the total solid content. It is 0.05 parts by mass or more, for example, 400 parts by mass or less, preferably 50 parts by mass or less, more preferably 25 parts by mass or less, still more preferably 7 parts by mass or less, and particularly preferably 4.5 parts by mass or less.

<Manufacturing method of coating material>
The method for producing the coating material of the present invention is not particularly limited. For example, the conductive pigment paste may be used as it is as a coating material, or the organic solvent may be removed or added as needed. The organic solvent is not particularly limited, but the same organic solvent as described in <Organic solvent (C)> of [Conductive pigment paste] can be used.
The method for producing a coating material of the present invention preferably includes a step of adding metal-containing particles having at least one metal element to the conductive pigment paste.

In the production of coating materials, conductive pigment paste, solvent, metal-containing particles, etc. are used, for example, a dispenser, a paint shaker, a sand mill, a ball mill, a pebble mill, an LMZ mill, a DCP pearl mill, a planetary ball mill, a homogenizer, and a twin-screw kneader. It is preferable to have a step of uniformly mixing or dispersing using a conventionally known stirrer or disperser such as a thin film swirl type high-speed mixer. In particular, it is more preferable to have a step of dispersing substantially without using media.

[Conductive coating film / conductive material]
The conductive coating film of the present invention can be obtained by applying (coating) the above-mentioned coating material to an object to be coated.
The conductive material of the present invention can be obtained by applying (coating) the above-mentioned coating material on both surfaces of a plate-shaped substrate. In the present invention, the conductive coating film is a liquid coating material. Is a solid film that has been heat-dried by applying the above to the object to be coated (base material). It can also be coated to obtain a conductive material.
The shape of the object to be coated is not particularly limited, and examples thereof include any shape such as a plate shape, a rod shape, a film shape, and a spherical shape.
The material of the object to be coated or the plate-like base material is not particularly limited, and for example, a metal material; various plastic materials; an inorganic material such as glass, cement, concrete; wood; a fiber material (paper, cloth, etc.), etc. It can be mentioned and may be a composite material of these.
As for the object to be coated or the plate-like substrate, the coated surface may be degreased, surface-treated or the like, if necessary.

The coating method is not particularly limited as long as it can be coated within a certain film thickness range, for example, roller coating, brush coating, atomization coating, dipping coating, applicator coating, shower coat coating, roll coater coating, and Daiko. Examples include tar painting.
The film thickness is a dry film thickness, for example, 1 μm or more, preferably 2 μm or more, and for example, 200 μm or less, preferably 150 μm or less.
The drying temperature is, for example, 60 ° C. or higher, preferably 80 ° C. or higher, and for example, 300 ° C. or lower, preferably 200 ° C. or lower.
By heating and drying, the solvent contained in the coating material is preferably eliminated by 80% or more, more preferably 90% or more, and particularly preferably 95% or more.
Further, it is preferable that at least a part of the organic compound (D) having reactivity with active hydrogen has disappeared due to a reaction, disappearance or the like.

Hereinafter, the present invention will be described in more detail with reference to Production Examples, Examples and Comparative Examples, but the present invention is not limited thereto. Unless otherwise specified, "parts" in each example indicates parts by mass, and "%" indicates "% by mass".

[Manufacturing of conductive pigment paste]
<Examples 1 to 44 and Comparative Examples 1 to 6>
The pigment dispersion resin (A), the conductive pigment (B), the organic solvent (C), the organic compound (D), and the film-forming resin (E) shown in Table 1 are listed in Table 1, respectively. The mixture was mixed in an amount (part by mass). Subsequently, a dispersion treatment was performed for 600 passes with an ultra-high-speed homogenizer (manufactured by Primix Corporation: trade name: Philmix) to obtain conductive pigment pastes X-1 to X-20.
The types and amounts of the pigment dispersion resin (A), the conductive pigment (B), the organic solvent (C), the organic compound (D), and the film-forming resin (E) shown in Table 2 are shown in Table 2, respectively. The mixture was mixed in an amount (part by mass), and then dispersed in a ball mill for 5 hours to obtain conductive pigment pastes X-21 to X-40.
The amount (parts by mass) of the pigment dispersion resin (A), the conductive pigment (B), the organic solvent (C), and the film-forming resin (E) shown in Table 3 are each shown in Table 3. Mixed in. Subsequently, in Examples 35 to 39, a dispersion treatment was carried out for 600 passes with an ultra-high-speed homogenizer (manufactured by Primix Corporation: trade name Philmix), and in Examples 40 to 44, dispersion was carried out with a ball mill for 5 hours. The organic compounds (D) of the types and amounts shown in Table 3 were added to the obtained pastes and mixed to obtain conductive pigment pastes X-41 to X-50.

For the conductive pigment pastes X-1 to X-50, the solubility parameter difference between the pigment dispersion resin (A) and the organic solvent (C), the rate of change in hydroxyl value and the evaluation (viscosity, storage stability, and conductivity) were determined. It is described according to Tables 1 to 3.
The water content of the conductive pigment pastes X-1 to X-39 was measured by the Karl Fischer titration method, and all of them were 0.1% by mass or less.

In the present invention, it is important that the performance of all items in the evaluation test is excellent, and if any one of them has a rating of "C", the conductive pigment paste is rejected.

[Constituents of conductive resin paste]
<Pigment dispersion resin (A)>
A1: Polyvinyl alcohol (saponification degree 97 mol%, SP value: 12.4, hydroxyl value: 1202 mgKOH / g, weight average molecular weight: 15,000)
A2: Carboxylic acid-modified polyvinyl alcohol (saponification degree 90 mol%, SP value: 12.5, hydroxyl value: 1078 mgKOH / g, carboxyl group concentration: 2.1 mmol / g, weight average molecular weight: 17,000)
A3: Polyvinyl alcohol (saponification degree 70 mol%, SP value: 11.2, hydroxyl value: 700 mgKOH / g, weight average molecular weight: 19,000)
A4: Polyvinyl alcohol (saponification degree 60 mol%, SP value: 10.8, hydroxyl value: 553 mgKOH / g, weight average molecular weight: 20,000)
A5: Polyvinylpyrrolidone (SP value: 12.8, weight average molecular weight: 10,000)
A6: Polymethyl methacrylate (SP value: 9.23, weight average molecular weight: 21,000)

<Conductive pigment (B)>
B1: Carbon black (acetylene black, average primary particle size: 20 nm)
B2: Carbon nanotubes (multi-walled, average outer diameter: 9 nm, average length: 20 μm)

<Organic solvent (C)>
C1: N-methyl-2-pyrrolidone (SP value: 11.2)
C2: Propylene glycol monomethyl ether (SP value: 10.4)

<Organic compound (D)>
D1: n-hexyl monoisocyanate (isocyanate compound, molecular weight 127)
D2: Methyltrimethoxysilane (alkoxysilane compound, molecular weight 136)
D3: Benzoyl chloride (acyllating agent, molecular weight 140.5)
D4: Benzoic anhydride (acyllating agent, molecular weight 226)
D5: Acrylamide (ethylenically unsaturated group-containing compound, molecular weight 71)
D6: Acetic acid (molecular weight 60)

<Film forming resin (E)>
PVDF: Polyvinylidene fluoride (weight average molecular weight: 800,000, solubility parameter δD: 9.1)

[Solubility parameter difference | δA-δC |]
Relationship between the solubility parameter δA of the pigment dispersion resin (A) and the solubility parameter δC of the solvent (C) | δA-δC | is the SP value of the solvent (C) from the SP value of δA of the pigment dispersion resin (A). It is the absolute value obtained by subtracting the value, and was calculated by the following formula.
| ΔA-δC | = | SP value of pigment dispersion resin (A) -SP value of solvent (C) |

[Rate of change in hydroxyl value]
In 8.45 g of the organic solvent (C), 0.10 g of the pigment dispersion resin (A) and the organic compound (D) are 2.7 times by mole (270) with respect to the total number of moles of the active hydrogen groups of the pigment dispersion resin (A). %) Add and heat at 100 ° C. for 1 hour. Then, the unreacted organic compound (D) was removed, and the hydroxyl value was measured based on JIS K 0070-1992.
Even when the organic compound (D) is not added as a blank, the measurement is carried out in the same procedure, and the rate of change in hydroxyl value is calculated by the following formula (1).
(OHV ⁰ -OHV ^* ) x 100 / OHV ⁰ ... (1)
OHV ⁰ : Hydroxyl value when the organic compound (D) is not added OHV ^* : Hydroxyl value when the organic compound (D) is added S: The rate of change in the hydroxyl value is 25% or more.
A: The rate of change in hydroxyl value is 15% or more and less than 25%.
B: The rate of change in hydroxyl value is 5% or more and less than 15%.
C: The rate of change in hydroxyl value is less than 5%.

[Evaluation test]
<Viscosity>
The viscosity of the obtained conductive pigment paste was measured at a shear rate of 1.0 sec-1 using a cone & plate type viscometer (manufactured by HAAKE, trade name: Mars 2, diameter 35 mm, 2 ° inclined cone & plate). Then, it was evaluated according to the following criteria. As for the evaluation, S, A and B pass, and C fails.
S: The viscosity is less than 1.0 Pa · s.
A: The viscosity is 1.0 Pa · s or more and less than 2.0 Pa · s.
B: The viscosity is 2.0 Pa · s or more and less than 5.0 Pa · s.
C: The viscosity is 5.0 Pa · s or more.

<Storage stability>
The obtained pigment-dispersed paste was stored at a temperature of 50 ° C. for 1 month, and the initial viscosity and the viscosity after storage were compared. The viscosity was measured at a shear rate of 1.0 s-1 using a cone & plate type viscometer (manufactured by HAAKE, trade name: Mars 2, diameter 35 mm, cone & plate inclined at 2 °). Storage stability was evaluated based on the viscosity increase rate obtained by the following formula (2). As for the evaluation, S, A and B pass, and C fails.
Viscosity increase rate (%) = Viscosity after storage / Initial viscosity x 100-100 ... (2)
S: The viscosity increase rate (%) after storage is less than 30%.
A: The viscosity increase rate (%) after storage is 30% or more and less than 100%.
B: The viscosity increase rate (%) after storage is 100% or more and less than 200%.
C: The viscosity increase rate (%) after storage is 200% or more.

<Conductivity>
The coating material was applied to a glass plate (2 mm × 100 mm × 150 mm) by the doctor blade method, and dried by heating at 130 ° C. for 30 minutes. After measuring the film thickness of the obtained coating film, the resistance was measured by a source meter (2400 manufactured by Keithley) using a four-probe probe (PSP manufactured by Mitsubishi Chemical Corporation). The conductivity was evaluated based on the volume resistivity obtained by multiplying the film thickness of the coating film and the resistance value. As for the evaluation, S, A and B pass, and C fails.
S: The volume resistivity is less than 10 Ω · cm, and the conductivity is very good.
A: The volume resistivity is 10 Ω · cm or more and less than 15 Ω · cm, and the conductivity is good.
B: The volume resistivity is 15 Ω · cm or more and less than 20 Ω · cm, and the conductivity is normal.
C: The volume resistivity is 20 Ω · cm or more, the conductivity is inferior, or a smooth coating film cannot be produced.

[Application example]
<Manufacturing of coating materials, conductive coating films and conductive materials>
Zinc oxide particles (average particles) as metal-containing particles having 50 parts of N-methyl-2-pyrrolidone as a solvent and at least one metal element in 100 parts of the conductive pigment paste obtained in Examples 1 to 44. Add 20 parts (diameter: 1 μm, electric conductivity of zinc: 16.8 × 10 ⁶ S / m), mix and stir for 60 minutes using a disper, and apply the coating materials Y to be Application Examples Y-1 to Y-34. -1 to Y-44 were obtained.
Subsequently, a cold-rolled steel sheet (150 mm (length) x 70 mm (horizontal) x 0.8 mm (thickness)) subjected to chemical conversion treatment with a zinc phosphate treatment agent (manufactured by Nihon Parkerizing Co., Ltd., trade name Palbond # 3020) is coated. As a product, the above-mentioned coating materials Y-1 to Y-34 are coated with an applicator so as to have a dry film thickness of 5 μm, and dried at a temperature of 150 ° C. for 40 minutes to obtain Application Examples Z-1 to Z-44. Coating films Z-1 to 44 were obtained.
The obtained coating films Z-1 to Z-34 all had a residual solvent amount of less than 1%, and were coating films having good finishability and the like.

Claims (20)

Pigment dispersion resin (A) having an active hydrogen group, conductive pigment (B), organic solvent (C), organic compound (D) having reactivity with an active hydrogen group, and a weight average molecular weight of 100,000 or more and solubility. Contains the film-forming resin (E) having a parameter δD of less than 9.3 ,
The conductive pigment (B) contains carbon nanotubes (B-1) and / or conductive carbon (B-2) having an average primary particle size of 10 to 80 nm .
The organic compound (D) having reactivity with an active hydrogen group is an isocyanate compound, an alkoxysilane compound, a compound other than a carboxylic acid that reacts with an active hydrogen group to form an acyl group, an epoxy compound, and α, β unsaturated. At least one selected from the group consisting of carbonyl group-containing compounds,
Conductive pigment paste. The conductive pigment paste according to claim 1, wherein the pigment dispersion resin (A) contains a hydroxyl group as an active hydrogen group. The conductive pigment paste according to claim 2, wherein the pigment dispersion resin (A) has a hydroxyl value of 100 mgKOH / g or more. The conductive pigment paste according to any one of claims 1 to 3, wherein the pigment dispersion resin (A) contains polyvinyl alcohol (a1) and / or modified polyvinyl alcohol (a2). The conductive pigment paste according to claim 4 , wherein the degree of saponification of polyvinyl alcohol (a1) and / or modified polyvinyl alcohol (a2) is 85 mol% or more and less than 100 mol%. The conductive pigment paste according to any one of claims 1 to 5, wherein the carbon nanotube (B-1) is a multi-walled carbon nanotube having an average outer diameter of 1 nm or more and 25 nm or less and an average length of 0.1 μm or more and 100 μm or less. .. Claim 1 to claim 1, wherein the conductive carbon (B-2) having an average primary particle size of 10 to 80 nm is at least one selected from the group consisting of acetylene black, ketjen black, furnace black, thermal black, graphene, and graphite. Item 6. The conductive pigment paste according to any one of 6. Any of claims 1 to 7, wherein the solubility parameter δA of the pigment dispersion resin (A) and the solubility parameter δC of the organic solvent (C) have a relationship of 0.6 << | δA-δC | <2.0. The conductive pigment paste according to item 1. The conductive pigment paste according to any one of claims 1 to 8 , wherein the organic compound (D) has a molecular weight of 1000 or less. The conductive pigment paste according to any one of claims 2 to 9 , wherein the pigment dispersion resin (A) and the organic compound (D) satisfy the requirement that the rate of change in hydroxyl value measured by the following method is 5% or more. ..
<Measurement method of rate of change in hydroxyl value>
In 8.45 g of the organic solvent (C), 0.10 g of the pigment dispersion resin (A) and the organic compound (D) are 2.7 times by mole (270) with respect to the total number of moles of the active hydrogen groups of the pigment dispersion resin (A). %) Add and heat at 100 ° C. for 1 hour. Then, the unreacted organic compound (D) is removed, and the hydroxyl value is measured based on JIS K 0070-1992.
Even when the organic compound (D) is not added as a blank, the measurement is carried out in the same procedure, and the rate of change in hydroxyl value is calculated by the following formula (1).
Rate of change in hydroxyl value = (OHV0-OHV *) × 100 / OHV0 ・ ・ ・ (1)
OHV0: Hydroxyl value when the organic compound (D) is not added OHV *: Hydroxyl value when the organic compound (D) is added OHV *: Hydroxyl value when the organic compound (D) is added The solid content of the pigment dispersion resin (A) is 0.1% by mass or more and 10% by mass or less based on the total solid content of the conductive pigment paste, and 0. The conductive pigment paste according to any one of claims 1 to 10 , wherein the amount is 1% by mass or more and 20% by mass or less. The content of the conductive pigment (B) is 50.0% by mass or more and 97.0% by mass or less based on the total solid content of the conductive pigment paste, and 3.0% by mass based on the total amount of the conductive pigment paste. The conductive pigment paste according to any one of claims 1 to 11 , which is 35.0% by mass or less. 13 . The conductive pigment paste according to any one of the above items. Pigment dispersion resin (A) having an active hydrogen group, conductive pigment (B), organic solvent (C), organic compound (D) having reactivity with an active hydrogen group, and weight average molecular weight of 100,000 or more and solubility. A method for producing a conductive pigment paste containing a film-forming resin (E) having a parameter δD of less than 9.3 .
The conductive pigment (B) contains carbon nanotubes (B-1) and / or conductive carbon (B-2) having an average primary particle size of 10 to 80 nm .
The organic compound (D) having reactivity with an active hydrogen group is an isocyanate compound, an alkoxysilane compound, a compound other than a carboxylic acid that reacts with an active hydrogen group to form an acyl group, an epoxy compound, and α, β unsaturated. At least one selected from the group consisting of carbonyl group-containing compounds,
A method for producing a conductive pigment paste. 14. The 14th aspect of the present invention is characterized in that the components containing the pigment dispersion resin (A), the conductive pigment (B) and the organic solvent (C) are dispersed and then the organic compound (D) is added and further mixed. The method for producing the above-mentioned conductive pigment paste. A coating material containing the conductive pigment paste according to any one of claims 1 to 13 . The coating material according to claim 16 , further containing metal-containing particles having at least one metal element. A method for producing a coating material, wherein metal-containing particles having at least one metal element are added to the conductive pigment paste according to any one of claims 1 to 13 . A conductive coating film obtained by coating the coating material according to claim 16 or 17 . A conductive material obtained by applying the coating material according to claim 16 or 17 to both surfaces of a plate-shaped base material.