Lithographic plate prepn - by treatment of copper plate with ferrocyanide ions

摘要

The lithographic plate is produced by treating the non-printing zones of a Cu (alloy) plate with an aq. soln. contg. ferrocyanide ions so as to make those zone hydrophilic. The ferrocyanide layer has good adhesion to the metal and provides good anchorage for photosensitive resins. Process is also applicable to zinc.