Yarn preparation for weaving: Sizing

Abstract: The chapter begins with the basic concept of sizing spun cotton and filament yarns. Yarn’s hairiness considered to be the most serious hazard in weaving single spun yarns in their unsized state is illustrated with full width weaving trials carried out on single unsized cotton and single unsized singed cotton yarns. It then covers the characteristics of different size materials as well as of a good size mixture. The chapter then deals with the importance of sizing weaving curve and the effect of size on adhesion between fibres in yarn structure. Sizing machines using cylinders drying and hot-air drying are illustrated in detail along with the factors that affect the percentage of size applied to a warp. The chapter finally covers briefly the automation controls of modern sizing machines.