| 摘要 |
PURPOSE:To easily obtain a lithographic original plate requiring no dampening water by coating a support with a photosetting resin having ink repellency, imagewise exposing the resin layer, and washing the unexposed portion with solvent. CONSTITUTION:Support 1 such as paper, a plastic film or metal foil is coated with a photosetting resin based on epoxy acrylate resin, polyisocyanate and alcohol- modified silicone oil to form resin layer 2. Layer 2 is imagewise exposed and washed with solvent. Since exposed portion 2A is solidified by polymn. and converted into a solvent resistant coat, it remains after the washing, and unexposed portion 2B is washed away. Thus, a lithographic original plate is formed. The set resin coat is ink repellent, so printing ink sticks to a portion corresponding to the unexposed portion alone, and a positive image can be printed. |
