GB1135031A - Process for imparting shrink resistance to wool and wool-containing materials - Google Patents

Abstract

1,135,031. Shrinkproofing wool. PRECISION PROCESSES (TEXTILES)) Ltd. 10 Feb., 1966 [11 Feb., 1965], No. 6077/65. Heading D1P. Wool and wool-containing materials are rendered shrink resistant by continuously passing them in a continuous form at substantially constant speed through a bath containing an aqueous liquor containing a shrink-resistance imparting oxidising agent for wool, a water soluble salt and a wetting agent e.g. the condensation product of trimethylnonyl phenol with 6 moles of ethylene oxide and continuously withdrawing the treated materials after a predetermined sojourn in the bath liquor, during which sojourn reaction takes place between the oxidising agent and the materials, whilst continuously withdrawing bath liquor at a predetermined rate and continuously introducing fresh aqueous liquor containing the oxidising agent, salt and wetting agent at a rate just sufficient to replace the withdrawn liquor, the concentration of oxidising agent in the fresh liquor just sufficing to replace the amount of oxidising agent consumed in the bath and any residual oxidising agent present in the withdrawn liquor whilst the concentration of wetting agent is substantially the same as that in the withdrawn liquor and the concentration of water-soluble salt in the initial bath is adjusted so as to be substantially equal to the concentration thereof in the fresh aqueous liquor so that the concentration of oxidising agent in the bath rises or falls with passage of the materials until an equilibrium is reached when substantially the desired consumption of oxidising agent takes place whilst the concentration of water-soluble salt therein remains substantially constant. The oxidising agent may be permonosulphuric acid and the water-soluble salt ammonium or potassium sulphate, or the oxidising agent may be sodium or potassium dichloroisocyanurate acidified to pH 2 with hydrochloric or sulphuric acid and the watersoluble salt sodium or potassium chloride or sulphate. If the woollen materials contain oil, an oil may be dispersed in the initial bath liquor in an amount at least sufficient to reduce overall gain of oil by the bath liquor during passage of. the -woollen materials therethrough. The materials may subsequently be treated with a reducing agent, e.g. sodium and potassium sulphites and bisulphites and mixtures thereof.