Mechanisms of Ink Release in Waterless Lithography.

Several models which could account for the phenomenon of ink release in waterless lithography are discussed. Among these are an equilibrium thermodynamic surface energy model, an elastic release model and a weak fluid boundary layer model. Evidence in support of the weak fluid boundary model and indicating the importance of ink solvent diffusion for achieving ink release is presented. The implications of this model for the utilization of solventless inks in waterless lithography and the problems inherent in printing with the high tack inks required to achieve release via the elastic release mechanism are also discussed.