Liquid, ph-sensitive ink, method and apparatus using the same

摘要

A novel liquid composition set is provided for forming an image or pattern by functional substances such as a colorant without causing blurring. Each of the liquid compositions of the set comprises a functional substance, an amphiphilic block copolymer or graft copolymer having an organic acid group, and a liquid medium, wherein the organic acid groups of the copolymers are different in pKa, and the amphiphilic polymer contained in the first liquid composition becomes viscous by pH change on contact with the second liquid composition different in pH from the first liquid composition.