abstract |
Provided is a novel copolymer effective as a binder resin and a pigment dispersant for water-based ink. A copolymer comprising a structural unit derived from maleic acid or a salt thereof, a structural unit derived from styrene, and a structural unit represented by the general formula (2). (2) R is H or a methyl group; L is a single bond or — (CH 2 ) n —O—CO—; n is an integer of 2 to 18; carbonyl in the aforementioned — (CH 2 ) n —O—CO— Carbon atom is bound to naphthyl) [Selection figure] None |