Patent ID: 7709184

Claim:
A method of developing a lithographic printing plate, comprising in order: (a) providing on a lithographic press a lithographic printing plate comprising (i) a substrate; and (ii) a thermosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to an infrared laser; wherein said thermosensitive layer exhibits an affinity or aversion substantially opposite to the affinity or aversion of said substrate to at least one printing liquid selected from the group consisting of ink and an abhesive fluid for ink; (b) imagewise exposing said plate with said infrared laser to cause hardening of said thermosensitive layer in the exposed areas; and (c) developing said exposed plate with ink and/or fountain solution on a lithographic press to remove the thermosensitive layer in the non-hardened areas; (d) wherein said press is shielded with covers that prevent at least 95% of the room light from reaching the plate mounted on the plate cylinder.