| 摘要 |
<p>PURPOSE:To obtain a composition, composed of a specific styrene-acrylic resin, a specified colorant and water, regulated within a specific pH region without any toxicity, excellent in writing properties, light and bleeding resistance and suitable for marking pens, etc. CONSTITUTION:The composition is composed of (A) water such as deionized water, (B) a styrene-acrylic resin having a molecular weight within the range of 1500-30000 and an acid value within the range of 150-300 in an amount of preferably 2-20wt.% (based on the total weight of the ink composition) and (C) one or more anionic dyes selected from (i) an azo metallic complex salt acid dye, (ii) C.I. Direct Black and (iii) C.I. Acid Yellow 110, C.I. Acid Yellow 127, C.I. Direct Yellow 100, C.I. 20215, C.I. 20216, C.I. 20230, C.I. 23266, C.I. 23635, C.I. 40002, C.I. 40215, C.I. 42655 and C.I. 42660 as a colorant in an amount of preferably 0.01-10wt.%, volatile at ambient temperature and regulated within the range of pH 6-9.5 with an alkaline substance such as ammonia.</p> |
