Platemaking Process overview / 수지판 제조 공정 오버뷰
Plates are produced in six basic steps:
1) Back Exposure
Back exposure sensitizes the plate, establishes the plate relief and improves the adhesion between the polyester support and the photopolymer. It is an exposure of the plate through the polyester base. The back exposure time is determined by a back
exposure step test.
2) Main Exposure
Main exposure is carried out through a film negative and forms the printing image. The exposed photopolymer becomes insoluble through a polymerization reaction. Because the image is formed by exposure, the plate can reproduce the finest details
of the original film negative.
Unexposed photopolymer is removed in the processor to produce a relief printing plate. A processing solution and brushing action are used to dissolve and
remove the unexposed photopolymer.
The washed-out plate swells during processing. The plate is dried to remove absorbed processing solution. Hot air drying is used. Drying returns the plate
to its original, uniform thickness.
Light finishing is used to remove surface tackiness. Tackiness is removed by short wavelength radiation in a proper light finishing unit. Plates can be light finished and postexposed (step 6) simultaneously in the proper equipment. If you do
not have a combination LF/PX unit, light finishing is done prior to post exposure.
6) Post Exposure
Post exposure completes the polymerization process. It ensures that the plate reaches its maximum strength and gains higher resistance against solvents
and stress. Post exposure is a uniform exposure of the dried plate. Post exposure can be run with or after light finishing for all plates.