| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a water-based ink capable of discoloring or decoloring color of handwriting, in which the change of color is suppressed even when allowed to stand in natural state and not forming thin spot of writing with time after packing the ink into a ball point pen. <P>SOLUTION: The water-based ink comprises at least water, a water-soluble organic solvent and a dye having a decoloring property, and the dye having the decoloring property includes C.I. basic green 4 and the content of oxalic acid and an oxalic acid salt in the ink is 0-0.2 wt.% expressed in terms of oxalic acid. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
