| 摘要 |
A method of making a lithographic printing plate comprising the steps of : (a) providing a lithographic printing plate precursor comprising a support having a hydrophilic surface or which is provided with a hydrophilic layer, and a coating on said support, said coating comprising (i) at least one image -recording layer which comprises a photocurable composition, said composition comprising a compound which is capable of forming free radicals upon image-wise exposure, and (ii) on top thereof, an oxygen-barrier layer comprising a water- soluble or water- swellable polymer, (b) image-wise exposing said coating, (c) optionally, heating the precursor in a preheating unit, (d) treating said image-wise exposed precursor with water or an aqueous solution to remove at least part of the oxygen-barrier layer, thereby increasing the oxygen permeability of the coating to such an extent that curing of the non-exposed areas of the coating by ambient light is inhibited by quenching of free radicals with oxygen, (e) mounting the treated precursor on a plate cylinder of a lithographic printing press, and (f) developing by rotating the plate cylinder while feeding dampening liquid and/or ink to the coating, thereby removing non- exposed areas of the image -recording layer. |
