| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for producing an ink composition that is almost free from the occurrence of the sedimentation of a pigment with the elapse of time, and is free from such a problem wherein the written lines are short of a pigment (coloring material) and blot easily when the pen point has been kept upward. <P>SOLUTION: The method for producing an ink composition comprised of at least a pigment as a coloring agent, a thixotropy-imparting agent, and a liquid solvent, comprises mixing the thixotropy-imparting agent with a single or a mixed liquid medium whose solubility parameter (SP value) is not more than 14.0, and then adding to the mixture a pigment and a liquid medium whose solubility parameter is more than 14.0. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
