| 摘要 |
<p>A waterless or driographic printing plate which can be thermally imaged by an infrared laser is composed of a substrate; a thermal imaging layer containing a photothermal conversion material, such as an infrared absorbing material, and a thermoplastic polyurethane with pendent allyl groups; and a cross-linked silicone polymer top layer. It was discovered that when the imaging layer contains an allyl functional polyurethane mixed with an infrared absorbing dye or pigment, the polymeric layer will have enhanced solubility in certain solvents when exposed to infrared radiation. In addition, the polymeric layer continues to exhibit excellent adhesion to the silicone in unexposed areas so that the infrared absorbing layer can endure development with a suitable organic solvent, or a solvent mixture. Mild brushing or rubbing with the developing solvent readily removes laser-struck portions of the infrared imaging layer while unexposed areas remain firmly intact.</p> |
