Comparison of colour values of plain cotton fabrics woven from ring- and compact-spun yarns

Abstract

The colour values of plain woven cotton fabrics made from ring- and compact-spun warp and weft yarns have been compared. Ring and compact cotton yarns were spun from 100% combed cotton at different yarn counts; ring-spun yarns having slightly higher mass irregularities and much higher hairiness than the compact-spun yarns. Fabrics having the same constructional properties were woven under the controlled mill conditions and then dyed with C.I. Reactive Black 5 dye. Reflectance measurements were performed oil the undyed and dyed fabrics and colour values (lightness, chroma and K/S) were obtained. It is observed that the colour values change with the change in yarn counts and differ in undyed and dyed fabrics. As the yarn counts increase, the lightness and chroma values increase but the K/S values decrease in dyed fabrics, while the results are opposite in undyed fabrics. The highest numerical differences are obtained between the chroma values of the fabrics. Microscopic photographs of the fabrics show that the hairiness decreases with the increase in yarn count. The yarn hairiness plays a very important role in light reflectances with regard to chroma values and fabrics woven from compact yarns appear lighter in colour because of the more regular structure of the compact-spun yarns.