WATER-BASED INK-JET INK COMPOSITION, METHOD FOR SUPPRESSING FADING OF PRINTED IMAGES ON SOLID FORMULATIONS, AND SOLID FORMULATION

摘要

Provided are: a water-based ink-jet ink composition capable of suppressing fading and discoloration of printed images on the surfaces of solid formulations such as pharmaceuticals and foods; a method for suppressing the fading of printed images on solid formulations; and a solid formulation. The water-based ink-jet ink composition contains an edible lake pigment and a discoloration inhibitor. The lake pigment includes a specific lake pigment comprising a dye containing at least one selected from the group consisting of red No. 2, red No. 3, red No. 40, red No. 102, yellow No. 4, yellow No. 5, blue No. 1, and blue No. 2. The discoloration inhibitor contains at least one selected from the group consisting of a monosaccharide, a disaccharide, a dextrin, and a sugar alcohol. The content of the discoloration inhibitor is 50 mass% or less with respect to the total mass of the water-based ink composition.