Continuous shrink-resist process of wool top sliver with ozone I performance

Continuous shrink-resist process of wool top sliver without use of chlorine agents has been recently developed in order to minimize Adsorbable Organic Halogens (AOX) being discharged from chlorine-based shrink-resisting process. The process consists of two steps of oxidation and subsequent reduction with bisulfite, i.e., (1) the oxidation with potassium hydrogen persulfate by pad/steaming as the first and (2) with ozone bubbled in acidic aqueous solution by a line mixer as the second. The characteristic feature of the proposed process was compared with other existing processes in view of comparison with properties of the treated wool. Washability performance of the treated wool products met with IWS TM 31 requirement. The treated fabric hand and fiber friction mu(a) of the tip to root direction were generally the same as those of similar fabric made from untreated control, while, the friction mu(w) of the root to tip direction increased. The difference of (mu(a)-mu(w)), i.e., D.F.E. was remarkably reduced probably leading to the high resistance to pilling of the treated fabrics. FT-IR, Allworden test and SEM observation revealed that the proposed process was a just surface treatment without serious damage to the cuticle, maintaining the yam strength and the water repellency of untreated wool.