Process for the manufacture of ultraviolet light absorbing cellulosic films

摘要

An article-forming cellulosic material is reacted in the presence of an alkali with a colourless 1:3:5 triazine derivative having the configuration where X is a bromine or chlorine atom, R1 is either an aminobenzene carboxylic acid radical or an amino-benzene sulphonic acid radical and R2 is a secondary amino group, not having the character of a dyestuff. Preferably the substituent or substituents attached to the nitrogen of the secondary amino group contains only carbon and hydrogen. Specified cellulosic materials include viscose and a solution of hydroxyethyl cellulose in sodium hydroxide. The cellulosic material is then extruded into a coagulation medium to form a shaped article, e.g. a filament or film, which absorbs ultra-violet light. In an alternative method, the shaped article is reacted with the 1:3:5 triazine derivative by passage through a bath containing an alkaline solution thereof. In the production of films, the proportion of triazine derivative reacted with the cellulosic material is desirably not less than 0.001/t x 2.0% by weight of the solid cellulosic material where t is the thickness of the film in inches. Specified triazine derivatives include 2-chloro-4-piperidino-1, 3, 5 triazinyl-amino-benzene -4-carboxylic acid; 2-chloro -4- dimethylamino-1, 3, 5-triazinylamino-benzene -4- carboxylic acid; 2 chloro -4- (N-methylaniline) -6- (41-carboxyphenylamine) -1, 3, 5 triazine; 2-chloro -4- (di-isobutylamino) -6- (4-carboxyphenylamino) 1, 3, 5 triazine; 2-chloro -4- piperidino -6-(21-carboxyphenylamine)-1, 3, 5-triazine and 2-chloro -4- piperidino-1, 3, 5 triazinylaminobenzene -4- sulphonic acid. Reaction requires about 10 hours at 25 DEG C. Specifications 495,479, 864,900, 871,087 are referred to.