03.11.11
Patent No. U.S. 7,780,778 B2
Nippon Paint Co., Ltd. has received a patent for a pigment dispersion consisting of a first pigment made of a coloring pigment having a primary average particle diameter of 200 nm or smaller, or made of carbon black having an average particle diameter of a structure of 100 nm or smaller, and a second pigment made of barium sulfate having a primary average particle diameter of 55 nm or smaller, a pigment dispersant and a medium. The first pigment and the second pigment are combined so that a value of (acid amount-base amount) of one pigment becomes positive, and a value of (acid amount-base amount) of the other pigment becomes negative, the combined first and second pigments being dispersed in the medium in the presence of the pigment dispersant, and the pigment dispersant being a nonionic or anionic pigment dispersant.
Nippon Paint Co., Ltd. has received a patent for a pigment dispersion consisting of a first pigment made of a coloring pigment having a primary average particle diameter of 200 nm or smaller, or made of carbon black having an average particle diameter of a structure of 100 nm or smaller, and a second pigment made of barium sulfate having a primary average particle diameter of 55 nm or smaller, a pigment dispersant and a medium. The first pigment and the second pigment are combined so that a value of (acid amount-base amount) of one pigment becomes positive, and a value of (acid amount-base amount) of the other pigment becomes negative, the combined first and second pigments being dispersed in the medium in the presence of the pigment dispersant, and the pigment dispersant being a nonionic or anionic pigment dispersant.