Patent ID: 6899998

Claim:
A method of preparing an off set printing plate usable in an offset lithographic printing system said method comprising the steps of: a) providing an offset lithographic printing blank having a hydrophilic surface; b) providing a quantity of substantially non-volatile photosensitive liquid coating comprising: water-soluble photo-curable oligomer prepolymers, and photoinitiators, said liquid coating further comprising a maximum concentration of 15% of water soluble binder, as measured by solid wt.; c) applying a thin layer of said liquid coating to said hydrophilic surface of said printing blank; d) digitally imaging said coating, in a non-contact fashion, using a non-coherent ultra-violet light source to polymerize portions of said liquid coating in accordance with said imaging; and e) washing said liquid coating with an aqueous solution after said imaging to remove unpolymerized portions of said liquid coating, to obtain an offset lithographic printing plate.