Patent ID: 7252926

Claim:
A planographic plate material comprising a support having thereon a photosensitive layer containing: (A) a photopolymerization initiator; (B) a polymer binder; (C) a polymerizable compound having an ethylenically unsaturated bond; and (D) an anionic dye, wherein the photopolymerization initiator is a an iron-arene complex, and the anionic dye has a solubility in methyl ethyl ketone of not less than 1 weight % based on the total weight of methyl ethyl ketone; and the anionic dye is represented by Formula (1): wherein R 1 represents a substituted or unsubstituted alkyl group of 1 to 18 carbon atoms, or a substituted or unsubstituted aryl group; R 2 to R 11 each independently represents a hydrogen atom, F, Cl, I, Br, a substituted or unsubstituted alkyl group of 1 to 6 carbon atoms, a substituted or unsubstituted aryl group or -N(R 12 ) (R 13 ), provided that R 12 and R 13 each independently represents a substituted or unsubstituted alkyl group of 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group; and X + represents a hydrogen cation, a monovalent alkali metal cation or an onium cation.