Waterless planographic printing plate with polysiloxane coating

Abstract

A waterless planographic printing plate having toner image areas of ink receptivity and non-image areas of ink releasability is provided, which plate has a substrate and an overlying layer coated on the substrate. The overlying layer is predominantly comprised of a reaction product of 50 to 99% by weight of a polymeric material having, on the average, at least two hydroxyl groups per molecule and exhibiting a high adhesion to the ink-receptive toner, and 1 to 50% by weight of an organopolysiloxane having hydroxyl end groups. The overlying layer preferably consists of a relatively thin surface layer substantially composed of the organopolysiloxane, and a relatively thick inner layer sandwiched between the surface layer and the substrate and having an islands-in-sea heterophase structure composed of the organopolysiloxane islands substantially uniformly dispersed in the sea of the polymeric material. The relatively thin surface layer has holes through which the inner layer predominantly composed of the polymeric material is exposed.

Dependencies are inferred from the claim text.