POSITIVE-WORKING LITHOGRAPHIC PRINTING PLATE

摘要

Positive-working lithographic printing plate precursors have an inner layer that includes a polymeric binder having an acid number of at least 30 mg KOH/g of polymer to and including 150 mg KOH/g of polymer, at least 3 weight % of recurring units derived from one or more N-alkoxymethyl(alkyl)acrylamides or alkoxymethyl(alkyl)acrylates, at least 2 weight % of recurring units having pendant 1H-tetrazole groups, and at least 10 weight % of recurring units having pendant cyano groups. The use of such polymeric binders in the inner layer provides good bakeability and chemical solvent resistance. Such positive-working lithographic printing plate precursors also include an outer layer disposed over the inner layer, which outer layer comprises an infrared radiation absorbing compound.

主权项

1. A positive-working lithographic printing plate precursor comprising:
a substrate, an imageable layer that is an inner layer disposed on the substrate, the imageable layer comprising a polymeric binder having an acid number of at least 30 mg KOH/g of polymer to and including 150 mg KOH/g of polymer, the polymeric binder comprising, in random order, at least 3 weight % of recurring units derived from one or more N-alkoxymethyl(alkyl)acrylamides or alkoxymethyl(alkyl)acrylates, at least 2 weight % of recurring units having pendant 11-1-tetrazole groups, and at least 10 weight % of recurring units having pendant cyano group, and an outer layer disposed on the inner layer, which outer layer comprises a polymeric binder different from the polymeric binder in the inner layer, and an infrared radiation absorbing compound that is present only in the outer layer.