PROCEDURE FOR PREPARING POSITIVE AND NEGATIVE PICTURES USING A PHARMACEUTICAL ELECTROSTATIC MASTER

摘要

Process for producing negative or positive images from a photohardenable electrostatic master comprising an electrically conductive substrate bearing a photohardenable layer containing a photoinhibitor and a visible light sensitizer wherein the negative image (1) is prepared by (a) imagewise exposing to visible radiation, (b) charging electrostatically the master, (c) developing the charged image with an electrostatic toner, e.g., liquid electrostatic developer, and (d) transferring the toner image to a surface, e.g., paper. The positive image (2) is prepared by (a) imagewise exposing to ultraviolet radiation, (b) exposing overall to visible radiation followed by steps (b), (c) and (d) above. Multiple images can be prepared from the same master as well as color proofs using different color toners or developers and transferring in register over the original image.