| 摘要 |
Provided are methods of preparing a positive-working lithographic printing plate, which methods comprise the steps of (a) providing a positive-working lithographic plate, such as a wet lithographic plate, imageable by laser radiation, which plate comprises an ink-accepting layer, (b) imagewise directing a source of radiation to image a first region of the ink-accepting layer in a desired pre-exposed pattern, and (c) imagewise directing laser radiation to image a second region of the ink-accepting layer in a desired final printing pattern, wherein at least a portion of the first region is not capable of being imaged during step (c) due to positioning of the plate during the exposure to the laser radiation and wherein the portion of the first region comprises areas which are capable of being inked and transferring ink to a receiver substrate during lithographic printing. Also provided are imaged lithographic plates prepared by such methods. |
