| 摘要 |
PURPOSE:To form a printing plate having higher ink repellency by using a silicone rubber layer obtained by addition reaction between a H-Si compd. and unsatd. bonds. CONSTITUTION:The silicone rubber layer is obtained by the addition reaction between a compd. having >=2 H-Si bonds in one molecule and a compd. having >=2 C=C bonds in one molecule. This rubber layer is used for the ink repelling layer, and when it is thin, problems, such as deterioration in ink repellency and easy scratchability, occur, and when it is thick, developability is deteriorated. Therefore, it is desirable to have a thickness or 0.5-50mum. The silicone rubber layer is formed by the addition reaction between the Si-H and C=C bonds and hardening, and it has a small amt. of silanol groups in the rubber as compared with the one obtained by the condensation reaction, and it is superior in ink repellency. |
