| 摘要 |
<p>PURPOSE:To obtain an Indian ink composition excellent in long-term dispersion stability and capable of being used for writing without diluting it by using an acidic carbon black in combination with a basic carbon black as pigments, a protective colloid, a surfactant and water as the main components. CONSTITUTION:This Indian ink composition contains an acidic carbon black and a basic carbon black in combination as pigments in an amount of 4.0 to 20.0wt.% in total, preferably in a ratio of 1:0.01 to 1:5.0. Further, this ink composition contains preferably 2.0 to 5.0wt.% protective colloid (e.g. a water-soluble resin such as gelatin or PVA) and preferably 0.1 to 5.0wt.% surfactant (preferably an anionic surfactant or a nonionic surfactant) and water as the main components.</p> |
