Patent ID: 7713681

Claim:
A method for preparation of a lithographic printing plate comprising: exposing with a laser a lithographic printing plate precursor comprising a support and a photosensitive layer containing a sensitizing dye, a radical polymerization initiator, a radical polymerizable compound and a binder polymer; and subjecting the exposed lithographic printing plate precursor to development processing with a developer having pH of from 3 to 9 to remove an unexposed area of the photosensitive layer, wherein the binder polymer is a polymer having an acid value of from 20 to 200mg-KOH/g and the developer comprises a compound represented by one of the following formulae <1> and <2>: in the formula <1>, R1 represents a substituent having the following structure: wherein R8 represents a hydrogen atom or an alkyl group; A represents a hydrogen atom, an alkyl group, a group containing an ethylene oxide group, a group containing a carboxylic acid group or a group containing a carboxylate; and B represents a group containing an ethylene oxide group, a group containing a carboxylic acid group or a group containing a carboxylate; and in the formula <2>, R2 and R3 each independently represents a hydrogen atom or an alkyl group, provided that at least one of the alkyl groups may have a substituent or a connecting group; C represents an alkyl group or a group containing an ethylene oxide group; and D represents a group containing an oxide anion.