Patent ID: 8106113

Claim:
An ink composition comprising at least a colorant (a) and a polymer (b) which is a colorant dispersant and which contains a repeating unit represented by the following formula (1): wherein R represents a hydrogen atom or a methyl group; J represents —CO—, —COO—, —CONR 1 —, —OCO—, a methylene group or a phenylene group; R 1 represents a hydrogen atom, an alkyl group or an aryl group; n denotes 0 or 1; W represents a single bond or a divalent connecting group; and P represents a heterocyclic moiety, wherein a hetero ring of the heterocyclic moiety is selected from the group consisting of benzimidazolone, quinoline, acridine, acridone, phthalimide, quinaldine and quinophthalone.