HEAT SENSITIVE PLATE PRECURSOR

摘要

A lithographic printing plate precursor comprises a grained and anodised aluminium substrate coated with a metallic layer, preferably a silver layer, on top of which is applied a layer of an oleophilic resin. Imagewise exposure of the precursor by means of a high intensity laser beam allows for the direct provision of press ready plates showing increased cleanliness in background areas and providing excellent start-up properties on press, high image quality and improved press durability, without the requirement for the use of intermediate film and developer chemistry, or the need for any post-exposure processing. Lower levels of metal deposition on the substrate surface result in the plate precursors showing enhanced sensitivity on exposure, whereupon removal of the metallic layer occurs in the exposed areas.