申请人:Usui Yuuma
公开号:US20130050363A1
公开(公告)日:2013-02-28
Disclosed is an aqueous ink composition, including an aqueous solvent, a coloring agent dissolved or dispersed in the aqueous solvent, an ABA-type amphipathic polymer including a hydrophobic segment A and a hydrophilic segment B, and an anionic surfactant configured to dissolve or disperse the ABA-type amphipathic polymer in the aqueous solvent, wherein a viscosity of the aqueous ink composition is changed depending on a pH thereof.