A Three-Color Black Printer.

A system is described for making a black printer for three-coIor printing, using existing halftone separation negatives. It is essentially a printing plate made by exposing through the three superimposed halftone separation negatives. An explanation and sensitometric data are given to support wet has proved to be a useful extension of the three-color printing program. Variations in the system of superimposing haIftone negatives are suggested to give unusual effects. Application of the system to the conventional positive - deep etch process is also suggested.