The purpose of the present invention is to provide an ink composition for ink-jet printers which is for painting or drawing on cosmetic surfaces, etc. using an ink-jet printer and which is excellent in terms of the dispersibility and redispersibility of a pigment, etc. and consists only of components that are permitted to be incorporated into cosmetics. The present invention relates to an ink composition for ink-jet printers, characterized by containing at least one copolymer selected from between (a) an alkyl acrylate/diacetone acrylamide copolymer and (b) an acrylate/C1-18-alkyl acrylate/C1-8-alkylacrylamide copolymer.本發明之目的在於提供一種噴墨列印機用墨水組合物，其係用於使用噴墨列印機於化妝料表面等進行描畫之墨水組合物，顏料等之分散性及再分散性優異，而且僅包含能夠調配於化妝料之成分。本發明係關於一種噴墨列印機用墨水組合物，其特徵在於含有選自(a)(丙烯酸烷基酯/二丙酮丙烯醯胺)共聚物及(b)(丙烯酸酯/丙烯酸烷基(C1-18)酯/烷基(C1-C8)丙烯醯胺)共聚物之至少1種。
