Abstract:
This invention relates to a tubular casing of cellulose hydrate having a coating on its inner side composed of a mixture of substances cross-linked by chemical reaction, which mixture is obtained when an aqueous liquid containing A. 1 to 10 per cent by weight, calculated on the total weight of the liquid, of a water-soluble aminoplast precondensate, B. 1 to 4 per cent by weight, calculated on the total weight of the liquid of a fluorine-containing two-component system from Beta 1. POLYMERS OF FLUORINE-CONTAINING ETHYLENE IMINES OF THE GENERAL FORMULA
WHEREIN Rf is a straight or branched, saturated perfluorinated carbon chain with 6 to 10 carbon atoms, and a 1 or 2, or polymers from mixtures of the said ethylene imines, dispersed in Beta 2. FLUORINE-CONTAINING COMPOUNDS OF THE GENERAL FORMULA
WHEREIN R''f is a straight or branched, saturated perfluorinated carbon chain with 5 to 7 carbon atoms, b 1 or 2, and c 18 to 50 (corresponding to polyethylene glycol groups with an average molecular weight of about 800 to 2,000), or in mixtures of the above compounds, provided that, in the component B of the liquid, the ratio Beta 1 to Beta 2 is in the range from 40 : 60 to 60 : 40 per cent by weight, calculated on the total weight of the liquid, and C. a water-soluble cross-linking catalyst, is heated sufficiently to remove the portion of the liquid consisting of water and sufficiently to effect cross-linking, whereby the aminoplast precondensate and/or reaction products of the aminoplast precondensate and the constituents Beta 1 and Beta 2 of the component B are chemically bonded with the OH groups of the cellulose hydrate forming the tubular casing.