PLANOGRAPHIC PRINTING PLATE AND PRODUCTION THEREOF

摘要

PURPOSE:To obtain the planographic printing which can be formed by dry processing by polymerizing layers contg. a polymerizable compd. and a polymn. initiator in the form of images to form a polymerized part surface and unpolymerized part surface and sticking powder only to the surface of the unpolymerized part by utilizing the difference in the tacky adhesiveness between the two surfaces. CONSTITUTION:The latent images consisting of the polymerized parts 2-a and the unpolymerized parts 2-b are formed according to the patterns of a mask 4 when an original plate 5 for planographic printing constituted by forming the polymerized layer 2 contg. the polymerizable compd. and polymn. initiator on a base 1 is exposed via the mask 4. An oxygen barrier layer 3 of the original plate for planographic printing formed with the polymerized latent images is peeled and the powder 6 is sprayed, by which the powder is stuck onto only the unpolymerized parts having the tacky adhesiveness. The original plate is then subjected to full-surface exposing by the same light source and the powder 7 stuck to the unpolymerized parts is fixed by the polymn. of the polymerizable compd. The planographic printing plate is obtd. if the excess powder is thereafter removed.