Patent ID: 7883827

Claim:
A planoaraphic printing plate precursor comprising a support and a photosensitive layer disposed on the support, wherein the photosensitive layer comprises a polymerizable composition comprising a binder polymer having a repeating unit represented by the following formula (I); an infrared absorbent; a polymerization initiator; and a polymerizable compound, wherein R 1 represents a hydrogen atom or a methyl group; R 2 represents a chain-structure linking group which includes one or more atoms selected from the group consisting of a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom and a halogen atom, and has a number of atoms of 2 to 30 except for substituents, wherein the chain-structure does not include a cyclic structure, and the chain-structure linking group has 3 to 30 carbon atoms and includes an amide bond or an ester bond; A represents an oxygen atom or —NR 3 — in which R 3 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms; and n represents an integer of 1 to 5; and wherein the binder polymer is a copolymer comprising a unit including a radical polymerizable group or a unit including an amide group.