GB473993A - Improvements in photographic films for use in colour photography and in processes for treating the same - Google Patents

Abstract

473,993. Photographic sensitive materials; colour photography. CINE COLOR, Inc. April 25, 1936, No. 11840. Convention date, June 8, 1935. [Class 98 (ii)] Photographic images are prepared from a film having superimposed images therein and one or more relatively reflective strata between the images which strata are either sufficiently translucent to allow the original images to be formed by a single exposure from one side or are originally translucent and are rendered opaque subsequently to the formation of the images, by exposing light-sensitive surfaces to light reflected from the strata. The strata may be insensitive or slightly sensitive. A two-colour film for the process comprises a support 11, Fig. 1, a red-sensitive or panchromatic emulsion layer 12, a separating layer 13, and a blue-green-sensitive layer 14. A red filter dye, e.g. congo red, may be applied to the outer surface of the layer 12 or between the layers 12 and 14. The stratum 13 contains a translucent substance capable of being rendered opaque and reflecting, e.g. zinc hydroxide titanium dioxide, or zinc oxide which are rendered opaque by treatment with a soluble sulphide. Alternatively, it may contain silver chloride or bromide mixed with excess of potassium iodide. The images in the layers may be copied successively onto double-coated film or simultaneously onto separate films, e.g. as shown in Fig. 3 in which the images on the film 10 illuminated by the light source 16 and mirrors 18, 19 are copied by the lenses 20, 21 on films 22, 23. When three sensitive layers are used, the image in the upper layer is copied and this layer then removed together with the underlying stratum.