Plate making device and printer and printing system using the plate making device

摘要

A plate material the surface of which is formed of film including as its major component a material whose surface changes from a lipophilic state to a hydrophilic state by a photocatalytic reaction and returns to a lipophilic state when subsequently subjected to a heat treatment is used for making a printing plate. The plate material is exposed to active light over the substantially entire surface thereof with image-wise part kept unexposed. The part exposed to the active light becomes hydrophilic and repels ink while the part unexposed to the active light is kept lipophilic and receives ink. When the plate material is subsequently heated, the hydrophilic part is rendered lipophilic and the plate material can be reused.