GB213647A - Improvements in kinematograph color films and methods of manufacture - Google Patents

Abstract

213,647. Thornton, J. E. Dec. 27, 1922. Drawings to Specification. Kinematograph picture films; colour photography; bichromated colloid processes.-Relates to positive films in natural colours, of the kind built up from thin component monochrome films as described in SpeciBoaticns 26786/11 and 25064/13, and consists in a flm built up by cementing together in register, with their image faces in contact, two films of half standard thickness, each carrying a series of monochrome pictures printed photographically in a readycoloured, non-waterproof colloid layer on a celluloid or like waterproof base, one series being orange-red and reversed with respect to the other, which is blue-green. The image-bearing colloid layers are protected from scratching by being enclosed between the celluloid or like base layers. For protection in handling the thin component films during printing, developing, &c., the films may be temporarily mounted during manufacture on a reinforcing layer of paper, which is not stripped off until the cementing operation is reached. The images may be produced in relief or non-relief by any known processes, numerous examples of which are stated, the preferred processes being the rapid silver bromide process, including the carbograph process, and the slow bichromated gelatine process employing pigments or dyes. The images may be printed separately or simultaneously from separate negative strips, or from a doubde-width negative strip carrying the component image series side by side, upon separate positive strips, or upon a double-width positive strip coloured orange-red and blue-green respectively on one side and on the other of the central longitudinal line. When separative positive strips are printed, the films carry marginal identification marks to facilitate correct assembly for cementing. Printing is performed (a) from the front for non-relief images, in which case the reinforcing strip of paper, if used, is carried on the celluloid or like back; or (b) through the back for relief images, in which case the reinforcing paper, if used, is carried on the colloid face, and is porous to permit access of developer &c. to the colloid layer. Registration is secured, during printing, in known manner, by means of accurately formed feed perforations. The component films are finally assembled face to face and cement together under pressure in accurate register. The reinforcing layers of paper, if used, are stripped off before cementing in the case of relief images, and either before or after cementing in the case of non-relief images. Specification 188,329 also is referred to.