The present invention provides a process for preparing a solid pigment composition for pigment ink comprising the steps of (a) dissolving polyvinyl alcohol in water, and dispersing pigments in the resulting solution; (b) adding aldehyde derivatives to the resulting pigment dispersion and allowing the polyvinyl alcohol to react with the aldehyde derivatives to prepare polyvinyl acetal; and (c) drying the acetalated pigment dispersion. The pigment ink resulted from the process, employs water-soluble solvents (for example, alcohol solvent, glycol solvent or other non-toxic solvents), contains sufficient amount of pigments, has low concentration with good pigment dispersion and storage stability, and shows good writing or recording ability with improved color-development.
本发明提供了一种用于制备
颜料墨
水的固体
颜料组合物的工艺,包括以下步骤:(a) 将聚
乙烯醇溶解在
水中,并将
颜料分散在所得溶液中;(b) 在所得
颜料分散液中加入醛衍
生物,并使聚
乙烯醇与醛衍
生物反应制备聚
乙烯醇缩醛;(c) 干燥
缩醛颜料分散液。该工艺制得的
颜料墨
水采用
水溶性溶剂(如醇溶剂、
乙二醇溶剂或其他无毒溶剂),含有足量
颜料,浓度低,
颜料分散性和储存稳定性好,书写或记录能力强,显色性好。