Patent GB-669185-A (GB)
Title: Improvements in or relating to methods of finishing textile fabrics and to the finishing composition used in said method
IPC: D06M15/263
Filed: 1948-04-15
Abstract: Aqueous solutions or dispersions of ammonium or amine salts of copolymers of styrene or a substituted styrene with maleic anhydride or with partial esters of maleic acid, suitable for the treatment of textile fabrics (see Group IV (c)) are prepared by adding the copolymers to a water solution of ammonia or an amine with stirring so that the salt is formed in situ.  The copolymer may for example be prepared by heating together styrene and maleic anhydride at 100-300 DEG  F. for several hours, using for each mol. of styrene between 0.25 and 4 mols. (preferably about one mol.) of maleic anhydride. Alternatively styrene and maleic anhydride may be reacted at slightly elevated temperatures in solution in acetone, if desired, in the presence of benzoyl peroxide.  Instead of styrene, methyl, butyl or chlorostyrene may be used, and instead of maleic anhydride, isopropyl maleate or secondary butyl maleate half esters.  In an example, 600 parts of the copolymer prepared by copolymerizing equimolecular quantities of styrene and maleic anhydride at about 200 DEG  F. are mixed with 400 parts of 27 per cent ammonia and 9000 parts of water. The mixture is maintained at 200-212 DEG  F. with stirring for about one hour. Textile fabrics are impregnated with the solution of the copolymer salt and during the subsequent treatment heated to 350 DEG F.  In another example 800 parts of the copolymer prepared by copolymerizing equimolecular quantities of styrene and the secondary butyl half ester of maleic acid at about 200 DEG  F., 530 parts of 27 per cent ammonia and 8670 parts of water are maintained at 200-212 DEG  F. for about one hour.ALSO:A glazed finish is produced on textile fabrics such as chintz by treating them with an aqueous solution or dispersion of an ammonium or amine salt of a copolymer of styrene or of a substituted styrene with maleic anhydride or with partial esters of maleic acid, and then passing the treated fabrics through a heated glazer.  The amine may be an alkylamine, such as methyl-, butyl-, or amyl-amine, guanidine, or a quaternary ammonium hydroxide, such as phenyl trimethylammonium hydroxide or trimethyl benzyl ammonium hydroxide.  The substituted styrene may be methyl, butyl or chlorostyrene and the partial ester of maleic acid may be isopropyl maleate or secondary butyl maleate.  The copolymer of styrene and maleic anhydride may be copolymerized with relatively small proportions of vinyl acetate, vinyl chloride, vinyl ethyl ether, indene, vinyl methyl ketone or acrylic esters.  The temperature of the impregnating bath may be room temperature to 212 DEG  F., and 2-15 per cent, preferably 4-7 per cent, of the salt may be deposited on the fabric.  The treated fabric may be undried or dried to a moisture content of 5-15 per cent prior to passing through the heated glazer or friction calender.  The aqueous solution or dispersion of the copolymer salt may also contain formaldehyde or a formaldehyde-yielding substance and the fabric may be given an additional curing after the glazing operation, e.g. by heating 10-15 minutes at 240-300 DEG  F.  Alternatively, small proportions, e.g. 10-20 per cent based on the weight of the copolymer, of certain melamine- and urea-aldehyde condensation products, e.g. of formaldehyde, may be added to the impregnating solution.  A second alternative is the application to the fabric, either before or after drying, or after friction calendering, of a dilute aqueous solution of a heavy metal salt, such as the chloride, acetate or formate of copper, aluminium, calcium or zirconium.  The aqueous solution or dispersion of the copolymer salt may also contain an oily or waxy softening or lubricating agent (e.g. a wax-like polyethylene oxide, a sulphonated tallow, a sulphonated oil, or a cation-active softener) which is capable of softening the fabric and of improving the glazing operation.  The fabric may be pretreated with 1-5 per cent of its weight of casein, a water-soluble cellulose derivative such as hydroxyethyl cellulose, carboxy-methyl cellulose, or methyl cellulose, or resin-treated starch.  In examples: (1) cotton print cloth is impregnated with sufficient of a 6 per cent solution of the ammonium salt of a styrene-maleic anhydride copolymer (see Group IV (a)) to deposit 6 per cent of the copolymer on the fabric, and dried at 180 DEG  F. to a 10 per cent moisture content; the fabric is then passed twice through a Perkins friction calendering machine at 350 DEG  F.; (2) cotton print cloth is treated in a similar manner with the same copolymer salt solution to which has been added 10 per cent of the methyl ether of tetramethylol melamine based on the weight of the copolymer; (3) a cotton fabric is treated as in example (1) except that the impregnated and dried fabric is treated with a 1 per cent aqueous aluminium formate solution for 10 minutes at 150 DEG F., thoroughly rinsed and dried to a 10 per cent moisture content before friction calendering; (4) cotton sheeting is treated as in the first example, but using an aqueous solution of the ammonium salt of a copolymer of styrene and the secondary butyl half-ester of maleic acid (see Group IV (a)).  In addition to cotton fabrics the treatment may be applied to fabrics made from cuprammonium rayon, viscose rayon, acetate rayon, nylon, linen, flax, hemp, jute, ramie, silk and casein fibres.  Fabrics treated according to the invention are said to have a substantially permanent finish, to be free from dusting and not to require a finishing wash.