Improvements in or relating to photographic medium and methods of preparing same

摘要

The photographic medium disclosed in the parent Specification formed by the vacuum evaporation of one or more of AgCl, AgBr and AgI and condensation of the vapours as a binder free layer of silver halide microcrystals not greater than 3.5 microns in thickness on a solid substrate such as glass, cellulose derivatives, polymers and polyesters or on a bonding substratum such as gelatin a lacquer or a tacky adhesive coated on the solid substrate or on a glass base coated on the solid substrate or on a glass base coated with silicon monoxide, is improved by applying to the silver halide coating a liquid pervious coating such as gelatin which is adapted to retain developed image silver in the binder free layer. The photographic medium may also be sensitized by the addition of a photographic sensitizer which may be combined with the crystals of the silver halide.