The object of fibre, yarn and fabric pretreatments is to prepare the material for subsequent coloration and finishing treatments. This is accomplished by removing the natural, acquired and applied substances which are mainly located at the fibre surface. In woven fabrics the size applied to the warp yarns to facilitate high efficiency in weaving is removed by desizing. The natural impurities associated with cotton fabrics, such as cotton waxes, pectin, protein, hemicelluloses and metal ions, are largely removed by scouring and any remaining pigments and seed-coat fragments are removed by bleaching.
展开▼
