Ink composition having excellent waterfastness

摘要

An aqueous solution ink composition is provided which yields a waterfast printed image, is fast drying, and is stable under typical printing conditions in an ink-jet printer. The ink composition is excellent with regard to its stability and the waterfastness of the printed image. The aqueous solution ink composition comprises an alkali-soluble polymer resin, a basic dye or an oil-soluble salt-type dye with the color imparting portion of the salt being cationic, and an alkali in an amount sufficient to completely dissolve both the alkali-soluble polymer resin and the dye.