| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition capable of erasing a letter, etc., written on a paper, a cloth, etc., when heated by dispersing a colorant obtained by reacting a leuco dye with a specified developer and developing a color, and a specific desensitizer in water as a main solvent. SOLUTION: This ink composition is obtained by dispersing (A) a colorant obtained by a reaction of (i) a leuco dye with (ii) a developer to develop a color and (B) a desensitizer (one or more of compounds, insoluble or slightly soluble in water, having >=40 deg.C melting point and preferably selected from poly-hydric alcohols, fatty acid esters, glycol ethers, urea derivatives, etc.), in (C) water. The content of component (B) is preferably 0.1-20wt.% and more preferably 0.5-10wt.% based on the total amount of the ink composition. For example, Crystal Violet lactone and di-β-naphthospiropyran are cited as the component (i). The component (ii) preferably has 100-200 deg.C melting point and is especially preferably bisphenol-A, etc. |
