| 摘要 |
<p>PURPOSE:To provide an ink compsn. which does not cause lowering in colored density even when handwriting is preserved over a long period of time and whose handwriting can be easily erased by an eraser, by dispersing a specified black pigment in an aq. medium contg. polyethylene oxide dissolved therein in the presence of a specified surfactant. CONSTITUTION:An ink compsn. is obtd. by uniformly dispersing a pigment (A) selected from among carbon black and Aniline Black in an aq. medium contg. polyethylene oxide (B) dissolved therein in the presence of a polyoxyethylene group-contg. surfactant (C) such as polyoxyethylene alkylphenyl ether. By using the pigment A and the compd. B as a stabilizer and an erasing accelerator for the ink and further adding the surfactant C as a dispersion accelerator, there can be obtd. advantages that letters and designs written in the ink compsn. can be erased by an eraser, writing can be made on traces of erased ink marks and handwriting can be preserved over a long period of time.</p> |
