| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an aqueous pigment ink for inkjet recording excellent in ink discharging stability in a thermal inkjet recording system and giving a high colored image on plain paper, and to provide an aqueous pigment dispersion from which the ink is easily prepared. <P>SOLUTION: The aqueous pigment dispersion contains carbon black, a styrene-acrylic copolymer, a basic substance and water as essential components. The carbon black has a primary particle diameter ranging from 20 to 30 nm, a specific surface area ranging from 100 to 150 m<SP>2</SP>/g, and a DBP oil absorption ranging from 40 to 120 mL/100g. The styrene-acrylic copolymer contains a benzyl (meth)acrylate monomer, in which the total of the styrene monomer and the benzyl (meth)acrylate monomer ranges from 45 to 80 mol% and the number of moles of the styrene monomer ranges from 65 to 95% with respect to the total number of moles of the styrene monomer and the benzyl (meth)acrylate monomer, and has an acidic number ranging from 110 to 220 (mgKOH/g). <P>COPYRIGHT: (C)2009,JPO&INPIT |
