GB424976A - Improvements in and relating to papers and cloths for photographic printing - Google Patents

Abstract

424,976. Photographic sensitive materials. HALDEN & CO., Ltd., J., and HOLDEN, J., Rowsley Works, Reddish, near Stockport. June 6, 1933, No. 16166. [Class 98 (ii)] [See also Group VIII] Photographic printing papers and cloths of the type used in industry such as " blue-prints " are rendered oil-proof by penetrating the material partially or completely with an oilresisting agent before, during or after sensitizing. The agent may be applied to one or both sides and may include insecticides, antiseptics, developing agents or dyes. The penetration may be assisted by the use of wetting agents such as sulphonated lorol, sulphuric esters of fatty alcohols, alkyl naphthalene sulphonic acids, alcohol, or dioxane. As oil proofing agents, colloids, such as casein or gelatin, cellulose esters, chlorinated rubber, or resins e.g. synthetic thermo-setting resins may be used, and hardening agents such as formaldehyde may be used in the case of colloids. Chlornaphthalene derivatives may be used as insecticides and chloramine T as an antiseptic. Examples are given of (1) paper sensitized with a ferroprussiate solution, e.g. that given in Specification 418,369, and treated with a solution of chlorinated rubber in benzene, (2) a diazotype paper treated with a solution of a celluloid varnish diluted with acetone and (3) a diazotype paper to the back of which a solution of casein, ammonia, and formaldehyde in water is applied.