2014 年 72 巻 1 号 p. 51-57
A highly sensitive photopolymerization system by using violet laser, 405 nm, was investigated. The photopolymerization composition which contained an initiator and a high fluorescent dye showed efficient sensitization of the system. The photosensitization mechanism seemed to have a singlet energy transfer process. A key molecular design of the dye getting the higher photosensitization efficiency is a repression of thermal relaxation from the excitation state. The photopolymerization system was applied to the computer to plate (CTP) technology, a digital printing plate, to develop our i-Presso P-NV for the violet laser. As compared with a system using a conventional FD-YAG laser, the P-NV system revealed the advantage of high productivity on plate making and also handling under a brighter safelight.