There is provided an ink composition containing a colorant, a solvent, and a binder composed of 80 to 98% by weight of a polyurethane resin, 0.5 to 5% by weight of a cellulose acetate alkylate resin and 1.0 to 15% by weight of a polyvinyl butyral resin, based on the solids content, in which composition the polyurethane resin is obtained by reacting a reaction product between (A) a polyether diol compound having a Mn of 1,000 to 5,000, or a mixture of the compound and a polyester diol having a Mn of 1,000 to 5,000, and (B) a diisocyanate compound, with (C) a hydroxyldialkylamine having a molecular weight of 50 to 300 and having one hydroxyl group in a molecule, and further reacting the product with (D) a chain extending agent; and a molar ratio of the OH group of the component (C) to the NCO group of the component (B) is 0.05 to 0.35.