Patent GB-1409167-A (GB)
Title: Colour diffusion-transfer photography
IPC: G03C8/44
Filed: 1973-07-05
Abstract: 1409167 Photographic diffusion transfer film unit FUJI PHOTO FILM CO Ltd 5 July 1973 [5 July 1972] 32187/73 Heading G2C A photographic diffusion transfer film unit comprises, in sequence, (1) an image-receiving element comprising on a transparent support a hydrophilic layer containing a mordant, (2) a photo-sensitive element having at least one photosensitive silver halide emulsion layer and containing associated with the layer at least one coupler developer (a colourless and alkali-soluble and diffusible compound having colour coupler and silver halide developer moieties) which forms a dye of a colour complementary to the sensitive region of the silver halide emulsion layer with which it is associated, (3) a water-impermeable sheet and (4) at least one of (a) a rupturable container capable of releasing, when ruptured, its contents between the image-receiving element (1) and the photo-sensitive element (2) and (b) a rupturable container capable of releasing, upon rupturing, its contents between the photosensitive element (2) and the water-impermeable sheet (3), the film unit also containing (5) an alkaline processing solution in at least one of (a) and (b) and also containing (A) an aromatic primary amino compound and (B) an oxidizing agent, either together or separately in one or more of the image-receiving element (1), the photosensitive element (2), the water-impermeable sheet (3) or at least one of the rupturable containers (a) and (b) and (C) an opacifying agent in (i) at least one of a layer disposed between the photosensitive silver halide emulsion layer of the photosensitive element (2) adjacent to the imagereceiving element and the mordant layer of the image-receiving element (1) and the rupturable container (a), or (ii) at least one of the waterimpermeable sheet (3) and the rupturable container (b). The coupler-developer may have the formula:- wherein (Coup) is a coupler group, (Link) is a linking group, e.g. alkylene, arylene, ether, thioether, carbonyl, sulphonylacylamino or amido, and R<SP>1</SP>, R<SP>2</SP> and R<SP>3</SP> are each H, OH, halogen, alkoxy or alkyl. The coupler developer may be in the silver halide emulsion layer or a layer adjacent the silver halide emulsion layer with which it is associated. The aromatic primary amino compound (A) may be a p-phenylenediamine derivative. The oxidizing agent (B) may be potassium ferricyanide, H 2 O 2 , potassium bichromate, ammonium persulphate, CuSO 4 , exposed silver halide or quinone. The photo-sensitive element may comprise an alkali-permeable support bearing a layer having dispersed in a hydrophilic colloid binder microcapsules containing a magenta coupler developer and a green-sensitive emulsion and micro-capsules containing a cyan coupler developer and a red-sensitive emulsion, a yellow filter layer, a blue-sensitive emulsion layer containing yellow coupler developer and a protective layer containing an aromatic primary amino compound. Two rupturable containers both containing an alkaline processing solution containing an opacifying agent are used with this photosensitive element, see Fig.10 (not shown).