Abstract: A filter for noxious gases such as sulphur dioxide or nitrogen dioxide comprises a keratinous fibre substrate within which is deposited an effective amount of manganese dioxide. The fibres, preferably sheep's wool, may be in the form of a fibrous bat and the manganese dioxide is deposited from acidified permanganate solution. The filter is most effective when maintained in the wet state.

Abstract: A method finishing keratinous textile articles, for example wool fabrics, which comprises treating the articles with an anti-felt polymer for example isocyanate functional or bunte salt functional polymers, and a polymer of chlorinated ethylenically unsaturated monomer, for example polyvinyl chloride, polyvinylidene chloride, polypropylene, and dichlorobutadiene. Thereafter, the articles are treated with an anionic titanium or zirconium complex at low pH. Textiles so treated exhibit both shrink-resistant and flame-retardant properties.

Abstract: A method of finishing keratinous textile fabrics is disclosed which comprises treating the fabrics with an anionic titanium or zirconium complex at a pH in the range 1 to 4, and with a halogen containing organic acid or anhydride soluble in hot water, but preferably virtually insoluble in cold water. Such a treatment enables wool furnishing fabrics to meet the very stringent National Fire Protection Association standard 701-1969.

Abstract: A method for improving both the flame-resist and smoke emission properties of natural polyamide fibers comprising applying thereto an anionic complex of zirconium, citric acid and fluoride at an acid pH.

Abstract: The flame resistance of wool and other polyamide fibres is enhanced by depositing in the fibres a complexed zirconium compound formed with an organic chelating agent or a halide. From 0.5 to 5% of Zr (as ZrO.sub.2) is preferred and the zirconium should be in the form of an anionic complex and applied at a pH in the range 0.5 to 4. The complex can be applied by impregnation or exhaustion techniques or may be formed in situ in the fibres. Dyes including acid, premetallized and reactive dyes can be applied at the same time as the zirconium complex. Particularly preferred complexes include fluorozirconates, chlorozirconates and oxalic and citric acid complexes. Fluorocarbon and other oil- or water-repellent finishes are compatible with the zirconium complex.

Abstract: Flame resistance of polyamide materials, notably wool and other keratinous materials, is enhanced by application of tungsten from acid solutions of anionic tungsten complexes. Still more effective treatment is obtained by simultaneously applying anionic complexes of zirconium or titanium. The complexes can be applied by exhaustion from a bath, preferably below pH 3.5 and at temperatures from 30.degree. to 100.degree.C. Dyes can be simultaneously applied from the same bath. Textiles can be padded in the solution and dried. The complexes may be isopolytungstates or heteropolytungstates and may be prepared with the help of organic carboxylic or hydroxycarboxylic acids.