DEVELOPING SOLUTION FOR PHOTOSENSITIVE PLANOGRAPHIC PRINTING PLATE, METHOD FOR PRODUCING PRINTING PLATE AND PHOTOSENSITIVE PLANOGRAPHIC PRINTING PLATE

摘要

PROBLEM TO BE SOLVED: To provide a developing solution for a photosensitive planographic printing plate capable of ensuring both no stain in printing and printing resistance without impairing image forming property, capable of dissolving a compound insoluble in a developing solution or stabilizing the dispersion of the compound for a long time and capable of also improving processing stability and to provide a method for producing a printing plate and a photosensitive planographic printing plate. SOLUTION: In the method for producing a printing plate, the photosensitive planographic printing plate having <=1.0 meq/g acid value of a photosensitive layer is exposed with laser light and developed with the developing solution of <=pH 13.0 in such a way that the developing speed of the unexposed part is adjusted to >=0.05μm/s and the rate of permeation of the developing solution into the exposed part is adjusted to <=0.1μm/s. The developing solution is a non-silicate developing solution containing an inorganic alkali agent and a nonionic compound of the formula A-W (where A is a hydrophobic organic group which satisfies (logP of A-H)>=1.5 and W is a nonionic hydrophilic organic group which satisfies (logP of W-H)<1.0). The photosensitive planographic printing plate has a photosensitive layer having 0.20-0.60 meq/g acid value and containing a compound having an acid group whose pKa is <=9.