摘要 |
The present invention provides a method for treating textile material to confer flame retardant properties, the method comprising the steps of impregnating the material with an aqueous solution of a treatment agent which is a poly(hydroxyorgano)phosphonium compound; drying the impregnated material; curing the dried impregnated material with ammonia to produce a cured, water-insoluble polymer which is mechanically fixed within the fibers of the material; oxidizing the cured polymer to convert trivalent phosphorus to pentavalent phosphorus; and washing and drying the material; wherein one or both of steps (d) and (e) result in the co-production of an aqueous effluent; and wherein the conditions are controlled such that the atomic ratio of N:P present on the material increases during step (c) by 0.8 or more. |