| 摘要 |
PURPOSE: A method of lithographic imaging without defects of electrostatic origin is provided to prevent defects of electrostatic origin in lithographic printing plates by reducing or minimizing the dielectric nature of the various plate layers and utilizing a conductive film for the substrate of the plate. CONSTITUTION: A method comprises the steps of 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; mounting the plate onto a grounded metal support so as to establish electrical contact between the support and the substrate; 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.
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