| 摘要 |
PURPOSE:To process photosensitive lithographic printing plates of both negative and positive types by using the same automatic developing machine without generating waste water by supplying the developing soln. to be exclusively used according to the types of photosensitive lithographic printing, subjecting the PS plates to a developing process, cyclically supplying aq. soln. contg. surface active agents to be exclusively used for the respective types to the plate surfaces and processing the plates with the same processing tank. CONSTITUTION:The developing soln. to be exclusively used for the negative or positive type photosensitive lithographic printing plate is supplied onto the photosensitive lithographic printing plate according to the type of the photosensitive lithographic printing plates to execute the developing process, then the aq. solns. contg. the surface active agents to be exclusively used respectively for said plates according to the types of the photosensitive lithographic printings used are cyclically supplied to the plate surfaces and the plates are processed in the same processing tank of the automatic developing machine. The stable formation of the lithographic printing plate which has the high non-sensitization characteristic in the non-image part, permits easy build-up and correction of developing ink and has a high grade is thereby made possible even in the case of subjecting the PS plates of both positive and negative types to the mixed process without washing by using the same automatic developing machine. |
