Patent GB-1163382-A (GB)
Title: Prevention of Felting and Shrinking of Wool-Containing Textile Material
IPC: D06M23/00
Filed: 1968-02-16
Abstract: 1,163,382. Shrinkproofing wool; treating textiles with liquids. LANEROSSI Sap.A. 16 Feb., 1968 [25 Feb., 1967], No. 7763/68. Headings D1L and DIP. The felting and shrinking of wool-containing textile material is prevented - by soaking it in a solution of sulphuryl chloride in a volatile organic solvent which is normally immiscible with water, e.g. trichloroethylene, perchloroethylene or carbon tetrachloride, for a period of time just sufficient for impregnation of the material, removing excess solution from the material while leaving therein a quantity of solution not exceeding the weight of the material, temporarily storing it for a period of time sufficient to cause the desired degree of felting or shrinking prevention and then removing the solution from the material, e.g. with an aqueous liquid or by steam. The volatile organic solvent is preferably such that it forms with water a minimum boiling azeotrope and the solution is preferably removed from the material by washing with hot water at a temperature exceeding the boiling point of the azeotrope to remove the solution still contained in the material by azeotropic distillation. In Fig. 1 in which all the vats and J-box are air-tightly sealed with respect to the external atmosphere, the material 10 to be treated, e.g. wool fabric, slivers or hanks or skeins bound to one another in chain form, is fed by rollers 25 to impregnating vat 12 where it passes through the bath 26 of sulphuryl chloride solution and excess solution is removed by rollers 27 before it passes down through J-box 14 provided with folding apparatus 15, the J-box 14 and vat 12 preferably being operated at 15-20C and impregnation in vat 12 taking few seconds and passage through J-box 14 approximately one hour. The material is then washed with water at room temperature in back-washing vat 16, neutralised in vat 18 which contains an aqueous solution of sodium acetate or other suitable salt at room temperature, passed through recovery vat 20 which contains hot water at a temperature exceeding the boiling point of the solvent/water azeotrope, the desired temperature in. the vat being maintained by heating means: 21 so that the azeotrope evaporates, treated with a solution of a softening agent in vat 22 and passed to a drier, passage the material through the vats being effected by means of rollers 28, 29, 38 and 39. Wash water continuously flowing out of vat 16 is preferably conveyed to a separator from which the heavy organic phase is recovered for reuse and the light aqueous phase is discarded. The azeotrope vapours evolved in recovery vat 20 are relatively heavy and accumulate immediately above the liquid level in vat 20 and are removed through a wide horizontal aperture 31 formed in at least one of the sidewalls of vat 20 just above the liquid level which communicates with a pocket attached to the vat wall in which is arranged a cooling coil to condense the vapours which separate into separate liquid phases, the heavy organic phase being recovered for reuse and the light aqueous phase being conveyed to the same separator as that associated with vat 16.