| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a marking ink composition which can stabilize the dispersion of a pigment and is excellent in prevention of whitening without impairing the dryability of written lines. SOLUTION: This composition comprises 2-20 wt. % organic and/or inorganic pigment, 55-85 wt.% lower alcohol, and 2-20 wt.% combination of two kinds of lower-alcohol-soluble polyvinyl butyral, one having an average degree of polymerization of 600-1,000 and the other having an average degree of polymerization of 300-500. Preferably, the ratio of the former polyvinyl butyral to the latter is (5/1)-(5/5).</p> |
