Patent ID: 7820361

Claim:
A lithographic printing plate precursor comprising: a support; and a photosensitive layer comprising (A) an initiator compound, (B) a polymerizable compound and (C) a binder, wherein the photosensitive layer or other layer in contact with the support comprises as (D) a component different from the component (C), a copolymer comprising (a1) a repeating unit having at least one ethylenically unsaturated bond introduced through an ion pair, wherein the repeating unit (a1) includes a repeating unit represented by Formula (A1): wherein R 101 to R 103 each independently represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, —CH 2 —OH, —CH 2 —OR 112 , —CH 2 —O—CO—R 112 or a halogen atom; R 104 to R 106 each independently represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, a halogen atom, —CH 2 —OH, —CH 2 —OR 108 , —CO 2 —O—CO—R 108 , —CO—R 108 , —O—CO—R 108 or —CO—N(R 109 )—R 108 , wherein —R 104 and R 105 or R 105 and R 106 may be combined with each other to form a ring; R 107 represents a methyl group, an ethyl group or a benzyl group; R 108 represents an alkyl group having from 1 to 10 carbon atoms or an aryl group having from 6 to 10 carbon atoms; R 109 represents a hydrogen atom, an alkyl group having from 1 to 10 carbon atoms or an aryl group having from 6 to 10 carbon atoms; R 112 represents an alkyl group having from 1 to 10 carbon atoms, an aryl group having from 6 to 10 carbon atoms or an aralkyl group having from 7 to 20 carbon atoms; L 101 represents a divalent connecting group selected from the group consisting of —CO—, —O—, —S—, —N(R 109 )—, —SO 2 —, a divalent aliphatic group, a divalent aromatic group and a combination thereof; L 102 represents a divalent connecting group selected from the group consisting of —CO—, —O—, —N(R 109 )—, a divalent aliphatic group, a divalent aromatic group and a combination thereof; m 101 represents an integer of 0 to 2; m 102 represents an integer of 1 to 3; m 101 +m 102 =3; when m 101 is 2 or more, plural R 107 groups may be the same or different from each other, when m 102 is 2 or more, plural R 104 , R 105 , R 106 and L 102 groups may be the same or different from each other, respectively; X 101 − represents —CO 2 − , —PO 3 H − , —O—PO 3 H − , —SO 3 − or —O—SO 3 − ; Y 101 represents an n 101 -valent connecting group; and n 101 represents an integer of 1 to 10; and (a2) a repeating unit having at least one functional group capable of interacting with a surface of the support.