Provided is a water-based ink composition for a writing instrument comprising at least a colorant and water, wherein a nonionic high molecular surfactant having an alkylene oxide chain as a hydrophilic group and having an average molecular weight of 3000 to 200,000 is added to the ink composition in a range of 0.1 to 30% by weight. The above nonionic high molecular surfactant has preferably an HLB of 8 or more or a cloud point of 50° C. or higher and includes N-polyoxyalkylene-polyalkylenepolyamine and a polyoxyethylene-polyoxypropylene block polymer.
本发明提供了一种用于书写工具的
水基墨
水组合物,该组合物至少包含一种
着色剂和
水,其中在墨
水组合物中加入了一种非离子型高分子表面活性剂,该表面活性剂以环氧亚烷基链作为亲
水基团,其平均分子量在 3000 到 200,000 之间,添加量为 0.1 到 30% (按重量计)。上述非离子高分子表面活性剂的 HLB 值最好为 8 或更高,浊点最好为 50 摄氏度或更高,其中包括 N-聚氧亚烷基-聚亚烷基环胺和聚氧
乙烯-聚氧
丙烯嵌段聚合物。