Patent ID: 7553605

Claim:
An ink composition comprising: (A) an N-vinyllactam; (B) a monomer represented by Formula (I); and (C) a radical polymerization initiator, wherein R 1 denotes a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbons, X 1 denotes a divalent linking group, each R 2 independently denotes a substituent, k denotes an integer of 1 to 6, each q independently denotes an integer of 0 to 5, the k R 1 s, the k X 1 s, and the q R 2 s may each be identical to or different from each other; and one carbon atom in the adamantane framework in Formula (I) may be replaced by a carbonyl bond (—C(O)—) and/or an ester bond (—C(O)O—).