| abstract |
An inkjet ink contains water, a hydrosoluble organic solvent, a pigment, polyvinyl pyrolidone, and a copolymer, wherein the copolymer contains a structure unit represented by Chemical formula 1, n n n n n n n n n n n n where R 1 represents a hydrogen atom or a methyl group, R 2 is an alkyl group having one to four carbon atoms, M 1 + , M 2 + , M 3 + , and M 4 + each, independently represent protons, alkali metal ions, or organic ammonium ions, and n a structure unit represented by Chemical formula 2, n n n n n n n n n n n n n n n n where R 3 represents a hydrogen atom or a methyl group, n a structure unit represented by Chemical formula 3, n n n n n n n n n n n n n n n n where R 4 represents a hydrogen atom or a methyl group, or n a structure unit represented by Chemical formula 4, n n n n n n n n n n n n n n n n where R 5 represents a hydrogen atom or a methyl group. |