GB613267A - Improvements relating to the shrinkproofing of materials consisting wholly or partlyof wool - Google Patents

Abstract

The shrinkage tendency of materials consisting partly or wholly of wool is reduced by the formation on the surface of the materials (which contain initially 10-30 per cent moisture) of an adherent solid polymeric deposit in amount between 1.5 and 4.0 per cent of the material, which deposit is produced by hydrolysis in water or dilute alkali of a silane of the type <FORM:0613267/IV (c)/1> when R is alkyl or aryl and X1, X2 and X3 bromine or chlorine, the material after treatment being washed. A mixture of a silane as above with one of general formula <FORM:0613267/IV (c)/2> may also be used, X1, X2, R1 and R2 having the same significance as above. The silane or silane mixture may be applied in solution or as a vapour, preferably at a temperature above 50 DEG C. After immersion in water the material is dried, the hydrolysis taking place during the drying. The firmly adhering deposit is resistant to scouring and to dry-cleaning agents. 5 per cent or more of it produces a rough fabric with abrasive properties, and in consequence reduced wear resistance. The feel of the fabric may be improved by treatment with a soap, cation-active compound or other softening agent. Long chain alkyl silanes give a soft handle when used in the extent of 20 per cent in a mixture, but used alone they do not give a good measure of unshrinkability. The wool may be dyed or dyed wool may be treated, but in the latter case the shade may be altered. In an example 100 g. of wool with a moisture content in equilibrium with the atmosphere is boiled for 20 minutes in 0.5 per cent by volume of methyl trichloro silane in carbon tetrachloride. After immersion in water for 10 minutes it is dried in a current of warm air, and washed in a soap solution. Area shrinkage of the fabric is reduced from 25 per cent to 4 per cent. Specification 594,901 is referred to in the Provisional Specification.