| 摘要 |
A composition for rendering fabrics water-repellent comprises 15 to 45 per cent by weight of a liquid methylhydrogen-polysiloxane of the formula (CH3)aHbSiO 4-a-b/2 , where a is 1.0 to 1.5, b is 0.75 to 1.25 and a + b is 2.0 to 2.25, 10 to 35 per cent of a liquid methyl polysiloxane containing 2.0 to 2.1 methyl radicals per silicon atom and having a viscosity of 1000 to 100,000 centistokes, and 20 to 65 per cent of a methylpolysiloxane resin of the general formula (CH3)xSiO 4-x/2 , where x has a value of 1.0 to 1.25. The resin is preferably added as a solution in an organic solvent which may be added to the polysiloxane mixtures. Catalysts are sodium bicarbonate, sodium aluminate and the acetates, hexoates, octoates, and naphthenates of lead, iron, zinc, manganese and cobalt. An organic acid, e.g. acetic acid, may be added as a stabilizer. The compositions may be extended either by diluting with a liquid hydrocarbon, chlorohydrocarbon, ether or alcohol, such as benzene, dioxane, ethanol or methylene dichloride, or by preparing aqueous emulsions, preferably containing emulsifying agents decomposable by heat, e.g. quaternary ammonium halides such as trimethylbenzylammonium chloride and hexadecyldimethylbenzylammonium chloride, or non-cationic emulsifying agents such as condensation products of fatty acids with organic amines. In examples, fabrics are treated with the polysiloxane mixtures, each component of which is prepared in known manner. Specifications 596,613 and 680,265 are referred to.ALSO:Fabrics of natural fibres, e.g. cotton, silk, linen and wool, or of synthetic fibres, e.g. nylon, orlon and viscose and acetate rayon, are rendered slip-resistant by wetting them with a liquid composition comprising three polysiloxanes (see Group IV (a)) and heating the wetted fabrics at 100 DEG to 475 DEG F. for 5 seconds to 1 hour. Catalysts may be added to the compositions, or after wetting the fabric with the polysiloxane composition, the wetted fabric may be dipped in a solution of the catalyst. The compositions may be applied to the fabrics (a) directly, (b) as solutions in organic solvents, or (c) as aqueous emulsions, preferably containing emulsifying agents decomposable by heat, e.g. alkylarylammonium halides, non-cationic emulsifying agents, e.g. amide condensation products of fatty acids with organic amines, being preferred in the treatment of cotton, wool and nylon. Specification 680,265, [Group VIII], is referred to.
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