| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide aqueous ink used for inkjet printing, a writing tool and the like which has a low sedimentation ratio enough to hardly cause clogging, causes no increase in its viscosity or the particle size of carbon black, can be stably preserved for a long period of time, and permits printing with a high printing density in deep black, and a modified carbon black dispersion used for manufacturing the same. <P>SOLUTION: The modified carbon black dispersion comprises modified carbon black, obtained by subjecting a carbon black bulk powder to an oxidation treatment, dispersed therein, and the modified carbon black bears on the surface thereof a carboxy group and a lactone group in a molar amount of 0.8-1.1 times that of the carboxy group and in an amount of at least 500μmol/g based on the weight of the modified carbon black. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
