Planographic printing block - consisting of carrier coated with polymer layer contg. image of hydrophilic or oleophilic zones

摘要

Planographic printing block consists of a carrier coated with a polymer layer contg. an image of hydrophilic and oleophilic zones in same plane. Layer in the hydrophilic or oleophilic zones consists of polymer binder which is free from ethylenically unsaturated monomer. In the othe zones, layer consists of a polymer binder and of a polymerised ethylenically unsaturated monomer. Process comprises (a) producing a photo-sensitive material by coating a carrier with a layer of photo-polymerisable material consisting of polymerisation inhibitor macromolecular organic polymer binder and addn. polymerisable ethylenically unsaturated extractable cpd. Photo-sensitive material is photographically exposed to actinic radiation; (b) leaching out ethylenically unsaturated cpd. of the unexposed zones, leaving only binder. Printing block operating either positively or negatively is obtd. by selecting binder and ethylenically unsaturated monomer.