GB459027A - Improvements relating to colour photographic printing - Google Patents

Abstract

459,027. Colour photography. GROVES, W. W., 30, Southampton Buildings, Chancery Lane, London.-(I. G. Farbenindustrie Akt.- Ges.; Frankfort-on-Main, Germany) May 29, 1935, No. 15212/36. Divided out of 460,653. [Class 98 (ii)] In a process of producing coloured prints on a multi-layer film from a set of component colour pictures, the latter are printed on to a multi-film having coloured layers to form a print giving incorrect colour values in projection, and this intermediate film is printed on a multi-layer film to form a print which gives correct colour values in projection. The intermediate film may contain dyestuffs for the dye-destruction process, or colourformers for colour development, or may be dyed after printing. The component colour pictures are printed through filters of the colours to which the layers to be printed on are sensitized. The blue component picture may be printed in a final yellow layer sensitized for red or green, and the layer of the intermediate film which is printed on this yellow layer is dyed blue-green or purple. Alternatively, the blue component picture is printed on the yellow and blue sensitive layer of the intermediate film, the green component picture on the blue-green and green sensitive layer, and the red-component picture on the purple and blue or red sensitive layer, the red component picture being printed from the opposite side to the blue and green components. In the final print the yellow layer of the intermediate film is printed on the yellow layer, the blue-green layer on the purple layer, and the purple layer is printed on the blue-green layer. The green layer may be dyed with Brilliant Benzo Fast Green or Congo Pure Blue, the red layer with Sirius Red Violet or Sirius Ruby B, and the yellow layer with Sirius Yellow R or Chrysophenine G or W. With films having two layers on one side of the support, and one on the other, the process is applied only to the superimposed layers. The colour component records may be in a lenticular bi-pack, and the intermediate' film, on which the lenticular front film is printed, carries superposed red and blue-green layers sensitized to red and blue respectively, and is processed by dye-destruction. The Blue component picture is printed with a green filter and the green component picture with a red filter. Intermediate films in which the difference from the final film is in gradation or in intensity of colouring are referred to.