| 摘要 |
The printing cylinder, for flexographic printing, is produced by the direct or indirect deposit of a layer with a constant thickness on a rigid support, using a plastics material which can form a photo mosaic. The material has no visco-elasticity when reticulated, and is in a liquid or paste form, and the layer is insulated. The gravure is applied directly by a light beam, to give the printed image using numerical control for the positioning and pulsation of the light beam. The plastics coating can be washed away by water, where it has not been exposed to the light. The outer surface structure is corrected as necessary during the production stages. The support cylinder (2) and the light source (3) are separated by a flat and transparent partition (4). The gap (5) between the partition (4) and the support cylinder (2) determines the thickness of the coating layer (7). The plastics coating material is delivered (6) by gravity into the gap (5). The cylinder (2) is rotated with a vertical upwards displacement. The photoaction of the plastics material is ended by insulation with an immersion of the coated cylinder at least partially in a watery medium. An Independent claim is also included for a flexographic printing cylinder with a monobloc plastics cladding. Preferred Features: The plastics cladding has a hardness /- 20 (70) Shore. The plastics material is produced by photo polymerisation. An intermediate layer can be between the rigid support cylinder and the cladding, with a shorter life than the cladding. The metal cylinder is solid or tubular. The plastics cladding has no charge.
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