Improvements in or relating to the recovery of celluloid and silver from scrap films

摘要

331,006. Pick, H. April 8, 1929. Cellulose nitrates.-Celluloid and silver are recovered from scrap films containing metallic silver by treating the unwound films first with warm dilute caustic alkali solution, stripping off the glue emulsion, and subsequently treating them for two or more hours with cold normal caustic alkali solution. The albuminous under coating which acts as an adhesive for the glue emulsion and the celluloid is thereby removed. By this method the celluloid remains transparent, and when dissolved in known solvents gives clear solutions. Specifications 16708/15 and 102,168, [both in Class 82 (i), Metals, Extracting &c], are referred to.