Materials Criteria for Waterless Lithography.

Waterless lithography or driography has been the subject of numerous recent patents. The optimization of materials for driographic printing, although considered important, has not been systematically treated. Based on the observations of Gaudioso, Becker and Sypula concerning a weak fluid boundary layer model for ink release, materials performance criteria for the master ink and image materials were formulated. These criteria were expressed in terms of their solubility parameters to allow for the optimization of materials and the choice of new and alternative materials for use in waterless lithography. The difficulty of attaining image adhesion to poly(dimethyl siloxane) master materials was predicted by these criteria The predictive capability of these criteria was further illustrated by demonstrating that ink release occurred from master materials having higher surface energy than poly(dimethyl siloxane. These master materials were poly(ethylene-co-propylene), polyisoprene and poly(vinyl alcohol).