GB610558A - Improvements in or relating to the production of photographic materials - Google Patents

Abstract

610,558. Coated fabrics. KODAK, Ltd., and SOPER, A. K. Feb. 21, 1946, No. 5396. [Class 140] [Also in Group XX] Paper or films of cellulose derivative or synthetic resin are treated with an organic derivative of silicon which imparts water repellant properties thereto and coated with an aqueous dispersion of a hydrophilic colloid. The water-repellant layer is formed by hydrolysis of the silicon compound, either by spraying the support with water, before or after the priming coating, or by the water normally present in the support if this is paper. The silicon compounds may be alkyl, aryl or alkaryl halogenosilanes. Suitable colloid binders are gelatin, polyvinyl alcohol, polyvinyl acetal and regenerated cellulose, and the binder itself may be made light-sensitive. A sheet of paper is passed over a trough containing a mixture of methyl chlorsilanes consisting mainly of the dichlor compound, the sheet forming a lid to the trough and being subjected to the vapour therefrom. A high contrast slow gelatino-silver halide emulsion is then coated on the treated surface; and, after drying, covered with a solution of cellulose nitrate in acetone containing tricresyl and triphenyl phosphates. Paper, may be treated on both sides with the hydrolizable silicon compound. Specifications 553,341, 554,292, 554,298, 554,300 and 554,301, [all in Group XX], are referred to.