| 摘要 |
PURPOSE:To reduce the extent of processing cost with one recirculating developer by measuring reflection density on the surface of a photosensitive planographic printing plate to be processed, discriminating between plate types of both positive and negative photosensitive plates, and varying a developing condition automatically according to this discrimination. CONSTITUTION:A discriminating reflection sensor 33 detects a different in the spectral reflection factor of photosensitive layer surface between both positive and negative photosensitive planographic printing plates by means of an optical sensor and it is constituted so as to discriminate between both plates. In addition, both positive and negative discriminating signals and a signal corresponding to a secular fatigue value are all inputted into a flow control circuit 37, and it is constituted so as to control a replenishing device 21 via a pump drive circuit 38 so as to have the replenishment of a replenish value based on a functional relation preset. With this constitution, using a developer in use of recirculation by an automatic developing machine, both these positive and negative photosensitive planographic printing plates are stably developable in common with each other, thus consumption of the developer is reducible and processing cost is adaptable too. |
