GB496698A - Improvements in or relating to the treatment of photographic film strips - Google Patents

Abstract

To remove shrinkage of exposed, developed, and fixed photographic cellulose acetate or nitrate films, and for surface regeneration thereof, they are swelled in an aqueous bath containing at least one liquid substance adapted to be absorbed physically by and to swell the film support, and to remain therein as softening agent after the water has been evaporated. The treatment may be repeated, if desired, with baths of different strength. The softening agents may or may not be solvents of the film material. The agents may be added to the wash water used after developing and fixing. The treating bath may be an aqueous solution of the phosphoric acid ester of a chlorinated aliphatic alcohol, e.g. that known under the trade name "Cetamoll (Qu)," or an aqueous solution of ethyl lactate, or an aqueous-alcoholic solution of triacetin, or any combination thereof. Reference is made to the addition to the bath of solvents of a lower boiling point, such as acetone and acetic ether, methylene chloride, and methyl alcohol, to produce an intensive surface effect; and also to a further preservative and regenerative treatment in known manner with a liquid containing softening agent of boiling point above 100 DEG C. dissolved in solvents of boiling point below 60 DEG C.; in the former category are mentioned lactic acid ethyl ester, chlorinated ethylene hydrine, glycerine triacetate, and benzyl alcohol or dibutyl phthalate; and in the latter category the low boiling solvents mentioned above. Specifications 259,265, 332,187, 336,217, [all in Class 2 (ii)], 359,971; and 364,082, [Group XX], are referred to.