Base plate and lithographic plate prepared by sensitization thereof

摘要

A base plate adapted to be coated with a light-sensitive diazo resin, and a lithographic plate which may be prepared therefrom. The base plate includes a substrate comprising a metal support and having a water-wettable, hydrophilic surface. Over the substrate and in direct contact with the surface is a layer comprising an oleophilic ink-receptive organic resin adapted to receive a light-sensitive coating comprising a diazo resin sensitizer. The oleophilic resin layer is permeable to the sensitizer so that it may penetrate substantially through the resin layer to establish sufficient contiguity between the diazo resin and the substrate so that both the light-sensitive coating and the organic resin layer become anchored to the substrate in the areas of exposure when the light-sensitive coating is exposed to light. Methods of preparing the base plate and lithographic plate are also disclosed.