Patent ID: 6055906
Filing Date: 2000-05-02
Classification: B41C

Abstract:
A method of imaging a lithographic printing member, the method comprising the steps of:a. providing a printing member including a polymeric top layer, an imaging layer, and a polymeric substrate, the imaging layer, but not the top layer, being formed of a material subject to ablative absorption of imaging radiation, the first layer and the substrate having different affinities for ink or a liquid to which ink will not adhere, the substrate, the imaging layer, and the top layer being conductive;b. mounting the plate onto a grounded metal support so as establish electrical contact between the support and the substrate;c. scanning at least one laser source over the printing member and selectively exposing, in a pattern representing an image, the printing member to output from the laser source during the course of the scan so as to ablate the imaging layer, thereby removing or facilitating removal of the top layer so as to directly produce on the member an array of image features;whereind. the array of image features includes at least one boundary region isolating an unimaged region; ande. electrostatic charge is applied to the top layer, the charge bleeding through the printing-member layers to ground, thereby preventing charge from arcing across the boundary region.