GB421727A - An improved method of producing photographic dyestuff images - Google Patents

Abstract

421,727. Colour photography. GASPAR, B., 38, Innsbruckerstrasse, Sch÷neberg, Berlin. June 23, 1933, No. 17962. Convention date, June 23, 1932. [Class 98 (ii)] Photographic dyestuff images are formed in photographic material comprising a sensitized, e.g. silver halide, layer and a juxtaposed layer containing a dye or dye forming substance, by subjecting the developed image in the sensitive layer to treatment, producing chemical reactions which act upon the adjacent layer to cause destruction or formation of the dyestuff therein. Thus, a layer containing a leuco body may be disposed above or below the sensitive layer and an oxidizing or catalytically-acting compound produced at the image or non-image portions, the dyestuff being developed by subsequent treatment with an acid or oxidizing agent as described in Specification 379,679. In a further example, a silver halide layer is disposed between two dyed layers and silver images formed on the outer surface of the middle layer by exposure from opposite sides, dye images being subsequently formed by treatment by dye destruction methods as described in Specifications 395,718, 397,188, and 397,192. Dyed gelatine layers may also be disposed between the support and light-sensitive layer, e.g. dyed layers may be applied to opposite sides of the support and silver halide layers applied thereover. Other described arrangements comprise a pair of dyed gelatin layers associated with a pair of thin silver halide layers, the latter being disposed between, or alternating with, the gelatine layers. The layers may also be employed in conjunction with light-sensitive layers containing dyes or dye formers. Specification 397,159 also is referred to.