Process for processing a photosensitive lithographic printing plate requiring no fountain solution.

摘要

A process for processing a water-free lithographic printing plate comprising a photosensitive layer and a silicone rubber layer laminated on a support in this order is disclosed, the process comprising the steps of imagewise exposing the lithographic printing plate; developing the exposed lithographic printing plate with an aqueous developer capable of peeling off substantially only the silicone rubber layer on the unexposed area; and then dyeing the image area with a dye solution containing at least one sparingly water-soluble compound and at least one hydrotrope agent or a dye solution comprising at least one compound represented by the following formula (I): R<1>O-(C3H6O)n-R<2> (I> wherein R<1> represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted alkenyl group; R<2> represents a hydrogen atom, an alkyl group, an aryl group, an aralkyl group or an alkenyl group; and n represents an integer of 2 or more. In accordance with the processing method according to the present invention, the non-image area can be efficiently plasticized without damaging the silicone rubber layer during processing, thereby improving the scratch resistance in handling and the press life during printing.