GB904354A - Improvements in felt-proofing and shrinkproofing wool and textiles containing wool - Google Patents

Abstract

Wool and wool-containing textiles are felt-proofed and shrink-proofed by impregnating them with a dispersion or solution of one or more polymers having molecular weights of at least 10,000 containing acid amide, urea or urethane groups, squeezing, possibly drying and then treating them with dichlorcyanuric acid and/or trichlorcyanuric acid as oxidising agents in aqueous solution or suspension. The polymers may be of natural origin or synthetically produced, e.g. polyamides such as copolyamides or polyamides derived from caprolactam, capryliclactam and hexamethylene diamine adipate, polypeptides, proteins, polyurethanes such as polyurethanes formed from polymethylolbutane-dioldiisocyanate condensates, polyureas, polyacrylamides, such as copolymers of acrylamide and methacrylamide, polysulphonic acid amides, polyvinyl pyrrolidone, and ureaformaldehyde reaction products. The wool may be subjected to a mild alkaline pretreatment, e.g. with an N/10 soda solution (liquor ratio 20 : 1 to 30 : 1) at 45 DEG C. for 1-2 hours. and then impregnated with the solution of dispersion of the polymer, squeezed and if desired dried. The wool may then be formalised moist or dry, e.g. using an aqueous liquor (liquor ratio 15 : 1 to 25 : 1) buffered to a pH of 5-7 containing 2% by weight of formaldehyde at 60 DEG -70 DEG C. for 1 1/2 -2 hours, and washed and is then treated with the aqueous solution or suspension of the oxidising agent which may be acid, neutral, or alkaline at room temperature or increased temperature, e.g. 20 DEG -40 DEG C. The treatment bath may contain dichlorcyanuric acid and/or trichlorcyanuric acid in an amount corresponding to 2-5% of active chlorine with reference to the weight of goods being treated and may also contain other oxidising agents, e.g. potassium permanganate, monopersulphuric acid and dipersulphuric acid and their salts, peracetic acid and perbenzoic acid, inorganic salts, e.g. calcium chloride, borax, magnesium sulphate and zinc sulphate, and/or organic salts, e.g. the alkali and alkaline earth metal salts of acetic acid and ethylene diamino tetracetic acid, and wetting agents. The wool may subsequently be subjected to a reductive or oxidative dechlorination bath, with, for example, an alkali metal bisulphite or dithionite, a salt of a hydroxy alkane sulphinic acid or a reaction product of such an acid with ammonia or hydrogen peroxide. Specification 891,217 is referred to.