| abstract |
To provide a copolymer including: a structural unit represented by the following General Formula (1) where X represents a hydrogen atom or a cation; a structural unit expressed by the following Structural Formula (1); and a structural unit represented by the following General Formula (2) where R is a hydrogen atom or a methyl group, L is a single bond or —(CH 2 ) n —O—CO— where n is an integer in a range of from 2 through 18, and a carbonyl carbon atom in the —(CH 2 ) n —O—CO— is bound to naphthyl. |