Method for producing conductive pigment paste

Abstract

To provide a method for producing a conductive pigment paste and a composite paste having excellent pigment dispersibility and storage stability even at a high pigment concentration and to provide a method for producing an electrode layer for a battery having excellent battery performance.SOLUTION: There is provided a method for producing a conductive pigment paste containing a pigment dispersion resin (A), a conductive pigment (B) and a solvent (C), wherein the pigment dispersion resin (A) has at least one polar functional group selected from the group consisting of an amide group, an imide group, an ether group, a hydroxyl group, a carboxyl group, a sulfonic acid group, a phosphate group, a silanol group and an amino group and a polar functional group concentration of 9 to 23 mmol / g, the conductive pigment (B) contains carbon nanotubes (B-1) and / or conductive carbons (B-2) having an average primary particle diameter of 10 to 80 nm, in which a powder raw material (P) containing the conductive pigment (B) is added in a liquid raw material (L) obtained by mixing the pigment dispersion resin (A), the solvent (C) and optionally other components, followed by mixing and dispersing by a media-less dispersion machine.SELECTED DRAWING: None

Claims

[Claim 1] A method for producing a conductive pigment paste containing a pigment dispersion resin (A), a conductive pigment (B), and a solvent (C), The pigment dispersion resin (A) has at least one polar functional group selected from the group consisting of amide groups, imide groups, ether groups, hydroxyl groups, carboxyl groups, sulfonic acid groups, phosphate groups, silanol groups, and amino groups, and the concentration of the polar functional group of the pigment dispersion resin (A) is 9 to 23 mmol / g. The conductive pigment (B) contains conductive carbon (B-2) or carbon nanotubes (B-1) with an average primary particle size of 10 to 80 nm and conductive carbon (B-2) with an average primary particle size of 10 to 80 nm. The content of conductive carbon (B-2) is 5 to 90% by mass based on the total amount of conductive pigment paste, and 40 to 99.9% by mass based on the total amount of solids in the conductive pigment paste. A liquid raw material (L) obtained by mixing a pigment dispersion resin (A), a solvent (C), and other optional components is mixed with a powder raw material (P) containing a conductive pigment (B), and the mixture is mixed and dispersed using a medialess disperser. A medialess disperser is a disperser that has a rotor and a stator inside a casing, and performs mixing, dispersion, and pumping by rotating the rotor. A method for producing a conductive pigment paste. [Claim 2] A method for producing a conductive pigment paste according to claim 1, wherein the powder raw material (P) is introduced by suction using the negative pressure generated when the rotor rotates. [Claim 3] A method for producing a conductive pigment paste according to claim 1, characterized in that, after mixing and dispersion using the medialess disperser, additional dispersion is performed using at least one disperser selected from the group consisting of a paint shaker, bead mill, ball mill, pebble ball mill, homogenizer, ultrasonic disperser, kneader, extruder, and planetary kneader. [Claim 4] A method for producing a conductive pigment paste according to claim 3, wherein the disperser used for additional dispersion is an annular bead mill. [Claim 5] The method for producing a conductive pigment paste according to claim 4, wherein the annular bead mill is a two-axis driven annular bead mill. [Claim 6] A method for producing a conductive pigment paste according to claim 3, wherein the disperser used for additional dispersion is an ultra-high-speed homogenizer or a high-pressure homogenizer. [Claim 7] A method for producing a conductive pigment paste containing a pigment dispersion resin (A), a conductive pigment (B), and a solvent (C), The pigment dispersion resin (A) has at least one polar functional group selected from the group consisting of amide groups, imide groups, ether groups, hydroxyl groups, carboxyl groups, sulfonic acid groups, phosphate groups, silanol groups, and amino groups, and the concentration of the polar functional group of the pigment dispersion resin (A) is 9 to 23 mmol / g. The conductive pigment (B) contains carbon nanotubes (B-1) and / or conductive carbon (B-2) with an average primary particle size of 10 to 80 nm. A liquid raw material (L) obtained by mixing a pigment dispersion resin (A), a solvent (C), and other optional components is mixed with a powder raw material (P) containing a conductive pigment (B), and the mixture is mixed and dispersed using a medialess disperser. A medialess disperser is a disperser that has a rotor and a stator inside a casing, and performs mixing, dispersion, and pumping by rotating the rotor. A method for producing a conductive pigment paste in which the pigment dispersion resin (A) contains ionic polyvinyl alcohol. [Claim 8] A method for producing a conductive pigment paste according to claim 7, wherein the degree of saponification of the ionic polyvinyl alcohol is 85 mol% or more and less than 100 mol%. [Claim 9] A method for producing a conductive pigment paste according to claim 1, wherein the solid content of the pigment dispersion resin (A) is 0.1 to 50% by mass, based on the total amount of solids in the conductive pigment paste. [Claim 10] A method for producing a conductive pigment paste according to claim 1, wherein the conductive pigment (B) contains carbon nanotubes (B-1), and the solid content of the pigment dispersion resin (A) is 5 to 50% by mass, based on the total amount of solids in the conductive pigment paste. [Claim 11] A method for producing a conductive pigment paste containing a pigment dispersion resin (A), a conductive pigment (B), and a solvent (C), The pigment dispersion resin (A) has at least one polar functional group selected from the group consisting of amide groups, imide groups, ether groups, hydroxyl groups, carboxyl groups, sulfonic acid groups, phosphate groups, silanol groups, and amino groups, and the concentration of the polar functional group of the pigment dispersion resin (A) is 9 to 23 mmol / g. The conductive pigment (B) contains conductive carbon (B-2) with an average primary particle size of 10 to 80 nm. A liquid raw material (L) obtained by mixing a pigment dispersion resin (A), a solvent (C), and other optional components is mixed with a powder raw material (P) containing a conductive pigment (B), and the mixture is mixed and dispersed using a medialess disperser. A medialess disperser is a disperser that has a rotor and a stator inside a casing, and performs mixing, dispersion, and pumping by rotating the rotor. A method for producing a conductive pigment paste, wherein the conductive pigment (B) does not contain carbon nanotubes (B-1), and the solid content of the pigment dispersion resin (A) is 0.1 to 20% by mass, based on the total solid content of the conductive pigment paste. [Claim 12] A method for producing a conductive pigment paste according to claim 1, wherein the content of conductive pigment (B) is 1 to 90% by mass based on the total amount of conductive pigment paste, and 10 to 99.9% by mass based on the total amount of solids in the conductive pigment paste. [Claim 13] A method for producing a conductive pigment paste according to claim 1, wherein the conductive pigment (B) contains carbon nanotubes (B-1), and the content of carbon nanotubes (B-1) is 1 to 20% by mass based on the total amount of the conductive pigment paste, and 10 to 99% by mass based on the total amount of solids in the conductive pigment paste. [Claim 14] A method for producing a conductive pigment paste according to claim 1, wherein the carbon nanotube (B-1) contains a multi-walled carbon nanotube. [Claim 15] A method for producing a conductive pigment paste containing a pigment dispersion resin (A), a conductive pigment (B), and a solvent (C), The pigment dispersion resin (A) has at least one polar functional group selected from the group consisting of amide groups, imide groups, ether groups, hydroxyl groups, carboxyl groups, sulfonic acid groups, phosphate groups, silanol groups, and amino groups, and the concentration of the polar functional group of the pigment dispersion resin (A) is 9 to 23 mmol / g. The conductive pigment (B) contains conductive carbon (B-2) or carbon nanotubes (B-1) with an average primary particle size of 10 to 80 nm and conductive carbon (B-2) with an average primary particle size of 10 to 80 nm. A liquid raw material (L) obtained by mixing a pigment dispersion resin (A), a solvent (C), and other optional components is mixed with a powder raw material (P) containing a conductive pigment (B), and the mixture is mixed and dispersed using a medialess disperser. A medialess disperser is a disperser that has a rotor and a stator inside a casing, and performs mixing, dispersion, and pumping by rotating the rotor. A method for producing a conductive pigment paste, wherein the conductive carbon (B-2) is at least one selected from the group consisting of acetylene black, Ketjen black, furnace black, thermal black, graphene, and graphite. [Claim 16] A method for producing a conductive pigment paste according to claim 1, wherein the solubility parameter δA of the pigment dispersion resin (A) is 9.3 or higher, and the solubility parameter δC of the solvent (C) is 10.4 to 15.

0. [Claim 17] A method for producing a conductive pigment paste according to claim 1, wherein the solubility parameter δA of the pigment dispersion resin (A) and the solubility parameter δC of the solvent (C) are in the relationship |δA - δC| < 2.

1. [Claim 18] A method for producing a conductive pigment paste according to claim 1, comprising dissolving a pigment dispersion resin (A) in a solvent (C) heated to 50°C or higher to produce a liquid raw material (L). [Claim 19] A method for producing a conductive pigment paste, wherein the conductive pigment paste obtained by the method described in claim 1 is substantially water-free. [Claim 20] A method for producing a conductive pigment paste, wherein the conductive pigment paste obtained by the method described in claim 1 is substantially free of metal. [Claim 21] A method for producing a composite paste, comprising adding at least one electrode active material to a conductive pigment paste produced by the method described in any one of claims 1 to 20. [Claim 22] A method for manufacturing a battery electrode layer obtained by coating a composite paste obtained by the method of claim 21 onto a current collector.

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