Patent ID: 6632589
Filing Date: 2003-10-14
Classification: B41C,C09B,C09D

Abstract:
A lithographic printing process comprising:(a) a step of providing an overcoat layer, which can be removed during printing, on a heat-sensitive lithographic printing plate original which includes a step of sequentially providing a hydrophilic layer and said overcoat layer on a heat-sensitive layer having an ink receiving surface; (b) a step of conducting image recording on said lithographic printing plate original provided with said overcoat layer which includes a step of subjecting to thermal action a surface of said heat-sensitive layer at a heating region, and, subsequent to said step of subjecting to thermal action, a step of decreasing adhesion between said heat-sensitive layer and said hydrophilic layer for forming an image portion at which said hydrophilic layer is removable; and (c) a step of printing, after said image recording, using emulsion ink that has been obtained by adding and emulsifying a hydrophilic component, which contains at least one of water and a polyhydric alcohol as a main component, into an oleophilic ink component, said step including a step of removing said overcoat layer and said heated region of said hydrophilic layer by supplying said emulsion ink to a plate surface during printing.