Diffusion transfer colour film and process compositions for supplying magnesium to animals and a process fo
Реферат: 1425835 Photographic colour diffusion transfer material POLAROID CORP 16 April 1973 [24 April 1972] 18138/73 Heading G2C A photographic material comprises layers forming a laminate or that are attached to one another and are capable of forming a laminate, the laminate comprising, in order, and in superposed relationship a transparent support, an image-receiving layer, a light-reflecting layer of metal pigment or means for forming such a layer, and at least one silver halide emulsion layer having associated therewith an image dye-providing substance, and an aqueous alkaline processing composition, the material also containing a compound capable of forming a coloured product with the metal ions from the metal pigment at an acidic pH and a metal complexing agent effective to reduce the formation of this coloured product. The material may contain an optical filter agent, which may contain at least one salicylic acid-type group, which is coloured at the pH of the processing composition but is colourless at a pH at which the coloured product can be formed. The metal pigment may be titanium dioxide. The metal complexing agent may be an aminopolycarboxylic acid e.g. ethylenediamine tetraacetic acid or N-(carboxymethyl)-N'- 2-hydroxyethyl -N,N'-ethylene glycine. The processing composition may contain ions of a second metal, e.g. aluminium, effective to further reduce formation of the coloured product. The lightreflecting metal pigment, optical filter agent and metal complexing agent may be present in the processing composition which may be contained in a rupturable container. The image dye-providing substance may be a dye-developer or colour coupler. The material may contain a neutralizing layer to reduce pH after development is complete. The material may comprise means for enclosing the silver halide emulsion layer(s) within an opaque envelope after exposure and before development is complete. The processing composition may contain a silver halide solvent and a second silver halide complexing agent, this complexing agent being capable of forming a relatively insoluble complex with silver halide. Stains are minimized or eliminated by the use of the metal complexing agent which forms a less coloured and more stable metal chelate than any other reagent present.
Color diffusion transfer photographic elements comprising a sulfur-substituted tetrahydropyrimidine development inhibitor precursor and process for their use
Номер патента: US3856520A. Автор: S Bloom,M Green. Владелец: Polaroid Corp. Дата публикации: 1974-12-24.