An experimental study of improving fabric appearance of denim by using low torque singles ring spun yarns

摘要

This paper presents an experimental study on the improvement of denim fabric appearance by reducing the residual torque of weft yarns. In this paper, 100% cotton low torque yarns of linear density 84 tex and 58 tex with different twist levels were produced by a new method of producing low torque yarns on a modified ring spinning machine. The results from the experiments show that the low torque yarns possess lower yarn snarling turns. Based on the mechanism analysis of 'small snake' pattern, the low torque ring yarns were applied to the denim fabric to improve fabric smoothness appearance. The experimental study demonstrates that the 'small snake' pattern of the denim fabrics has been greatly decreased by using the low residual torque ring yarns as weft yarns. Objective measurements of the low stress mechanical and surface properties of denim fabrics using low torque and conventional yarns were conducted. The results show that the denim fabric using the low torque ring yarns as weft yarns presents a smoother and more even surface. Moreover, a multiple comparisons LSD test of fabric properties indicates that there is no significant difference on tensile strength and tearing strength between fabric samples using the low torque ring yarns and conventional ring yarns with normal twist level as weft yarns, respectively. In addition, the experimental results demonstrate that the 'small snake' pattern of the fabric decreased with the reduction of weft yarn snarling.