| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing an aqueous ink composition for a ballpoint pen, the composition suppressing blurring or writing failure caused by clogging of an aggregated pigment at a pen tip. SOLUTION: The method for producing aqueous ink for a ballpoint pen containing at least a pigment, water and polysaccharides is characterized in that polysaccharides having a molecular weight of about 1×10<SP>6</SP>to 1×10<SP>13</SP>is used by 0.05 wt.% or more and 0.3 wt.% or less with respect to the whole amount of ink, and a pigment is added to a preliminarily prepared aqueous dispersion of the polysaccharides, and then stirring and mixing are performed. COPYRIGHT: (C)2011,JPO&INPIT |
