Abstract: A method for making a lithographic printing plate according to the silver salt diffusion transfer process image-wise exposes an imaging element with a high intensity short time scanning exposure. The imaging element comprises on a support in the order given a silver halide emulsion layer and a layer containing physical development nuclei. A thus obtained image-wise exposed imaging element is subsequently developed in the presence of a developing agent and silver halide solvent. The image-wise exposure is focused substantially within the silver halide emulsion layer of the imaging element. The present invention further provides an apparatus for carrying out the above method.

Abstract: A method for generating on a lithographic printing plate a screened reproduction of a contone image, comprising the steps of: (1) transporting a thermo-sensitive imaging element through an exposure area; (2) scanwise exposing the thermo-sensitive imaging element according to screened data representative for tones of a contone image with a set (s) of radiation beams (b) as the thermo-sensitive imaging element is transported through the exposure area, characterized in that at any given moment (ta+.DELTA.t) during the exposure at least two radiation beams (bi,bj) of the set of radiation beams impinge on different microdots (ma, ma+.DELTA.m) of a scanline (1a) on the imaging element, so that by completion of the exposure step each effective microdot of the scanline has been impinged by all effective radiation beams of the set.

Abstract: An apparatus for making a lithographic printing plate according to the silver salt diffusion transfer process image-wise exposes an imaging element with a high intensity short time scanning exposure. The imaging element comprises on a support in the order given a silver halide emulsion layer and a layer containing physical development nuclei. A thus obtained image-wise exposed imaging element is subsequently developed in the presence of a developing agent and silver halide solvent. The image-wise exposure is focused substantially within the silver halide emulsion layer of the imaging element.