| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a water-based ink which has a good thermal discoloring action independently from the kind of a written surface or a printed surface without increasing the viscosity of the ink. <P>SOLUTION: This water-based ink composition discolored with an organic solvent and/or heat comprises a coloring agent obtained by coloring fine resin particles with a coloring substance and at least one of water-soluble amino acids, their salts, and their derivatives. For example, the fine resin spheres comprise one or more polymers selected from polymers or polyolefins containing acrylonitrile, styrene acrylic acid, methacrylic acid, methyl acrylate, and methyl methacrylate as constituting units. <P>COPYRIGHT: (C)2003,JPO</p> |
