| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a water-based pigment ink composition having excellent color-developing property on a common white paper sheet and excellent dispersion stability of the pigment and storage stability and, accordingly, giving a high-density written mark in the case of using in a writing utensil and a high-density inkjet image in the case of using in an inkjet printer. <P>SOLUTION: This water-based pigment ink composition contains water, a pigment, a water-soluble resin, a surfactant composed of a phosphoric acid ester, and an O/W-type emulsion of at least one kind of a water-insoluble resin selected from acrylic resins, styrene resins and styrene-acrylic resins. The resin particle in the emulsion has an average particle diameter of 50-200 nm and the lowest film-forming temperature of the emulsion is ≥50°C. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
