GB274591A - Improvements in kinematograph and other colour films and methods of manufacture - Google Patents

Abstract

274,591. Thornton, J. E. May 6. 1926. Drawings to Specification. Colour photography; films and papers, stripping. - Raw material for the production of positive kinematograph films, strip or single photographs, lantern slides, window transparencies, &c. of the kind comprising a transparent waterproof support such as celluloid or glass carrying a ready-coloured sensitive colloid layer upon which is laid a temporary reinforcing layer of paper, and wherein the colloid layer is united on the one side to the support and on the other to the paper layer by an adhesive substratum, is manufactured in two parts which are cemented together to produce the finished material. In one method, the transparent support is coated first with a substratum and then with the colloid layer, and the paper is coated with a substratum, the two parts so produced being then united by moistening the colloid layer, or the substratum on the paper, and pressing the two parts into adhesive contact. In an alternative method, the colloid layer is coated on the substratumed paper instead of on the substratumed support, and the parts are united as in the first method. The substratum between the support and the colloid is an insoluble layer containing, for example, hardened gelatin, while that between the paper and the colloid is soluble, for example, a layer of soluble gelatin, so that when the material is developed to produce relief or non-relief images after exposure through the support, the colloid remains attached to the support, while the paper layer becomes detached and is discarded. Sensitizing is effected either by bichromate or other slow-printing salts, or by rapid printing silver salts, and the colouring- matter comprises either pigments or mordanted dyes or both. The back of the support may be coated with an anti-curling hardened gelatin layer united to the support by an insoluble substratum. For monochrome pictures, the material may be manufactured of single picture-width, or of double picture width one half of which carries the sensitized coloured colloid, and the other half plain unsensitized colloid, this half serving merely as a covering layer when the double-width material is severed, after printing, &c., and the two halves are cemented together. For multicolour pictures built up from two, three, or four colour components the material may be of single picture width for each component, or may be manufactured respectively of double, triple, or quadruple width carrying side-by-side areas of colloid coloured with the desired colours, and intended to be slit after printing &c. in order that the components may be cemented together. If the side-by-side areas of colloid on a multi-width film are coloured by applying dyes to the alreadycoated colloid, the areas are isolated from one another to prevent running of the dyes by narrow lines of hardened colloid produced by local application of a hardening solution. Specifications 214,934 and 224,571 are referred to.