| 摘要 |
<p>A water-base erasable ink composition for use in marking pens which comprises: (a) water as a solvent; (b) a colorant dispersed or dissolved in the water in an amount of 0.5-20% by weight; (c) a water soluble polyvinyl acetal resin as a film-forming agent in an amount of 0.1-15% by weight; and (d) an aqueous emulsion of an aliphatic carboxylic acid ester which is liquid and nonvolatile or only slightly volatile at room temperatures as a separating agent in a dry amount of 1-20% by weight. The ink composition preferably further comprises a polyoxyethylene polyoxypropylene block copolymer, or a lanoline derivative, in particular, ethoxylated cholesterol or ethoxylated isocholesterol, or both of these, as a writing separation assistant.</p> |
