GB492648A - Improvements relating to colour photography - Google Patents

Abstract

492,648. Colour photography. GROVES, W. W. (I. G. Farbenindustrie Akt.-Ges.) Jan. 20, 1937, No. 1705. [Class 98 (ii)] A photographic material having several silver halide emulsion layers containing dyestuff components fast to diffusion for the production of a colour picture and a separate panchromatically sensitized silver halide emulsion layer for the black-and-white picture is used for producing coloured. photographic pictures to be viewed by transmitted or reflected light and having a black-and-white picture in addition to the colour picture. The silver of the additional layer may be used for producing the black picture, or the layer may contain dyestuff components yielding either black dyestuffs or yielding dyestuffs convertible into black products by treatment with simple or complex metallic salts or on treatment with an azo-component. The silver picture may be toned by complete or partial conversion to silver sulphide, silver thiophenolate or silver iodide. The additional layer may be the top layer or may be on the rear side of the carrier, and may also serve as a filter or mat layer. The colour picture may be produced by colour development, the silver dyestuff bleaching out process or the antidiazotate process. In an example there are superimposed on a carrier a panchromatic emulsion containing a dyestuff component fast to diffusion yielding on colour development a blue image, an orthochromatic layer containing a dyestuff component fast to diffusion yielding on colour development a red image, a non-colour sensitized layer containing a dyestuff component fast to diffusion yielding a yellow image on colour development, and a top panchromatically sensitized layer containing all three dyestuff components or containing a dyestuff component fast to diffusion, such as N-dodecyl-1 : 2-hydroxynaphthoyl-aminocarbazole, yielding a black image on colour development. In another example the lowermost layer is orthochromatic and contains a dyestuff component fast to diffusion yielding a red picture on treatment according to the antidiazotate process using dianisidine tetrazotate ; the next layer is orthochromatic and yields a yellow picture ; and the top layer is panchromatic and contains either the dibenzidide of 2 - hydroxynaphthocarbazole- 3-carboxylic acid or N-dodecylaminophenylhydroxynaphthothiazolesulphonic acid; both yielding a black picture. On the other side of the support is a panchromatic layer in which a blue picture may be produced by toning according to the Prussian blue process. The layer for the black-and-white picture may be on the opposite side of the support, and the sound record may be produced in this layer. The material may be processed by simple colour development or reversal. Specifications 387,197, 436,587, 458,400, 465,823, 468,946, 475,191, 479,838, 481,501, 483,000, 484,698, 488,853, 489,093, 489,161, 489,164, 489,274, and 490,517 are referred to.