Siro false twist spun yarn structure and the knitted fabric performance

Abstract

False twisting has been used to reduce yarn twists while keeping yarn tenacity, which is vital to improve fabric softness. In this paper, a false twisting device was integrated into a siro spinning system to develop a novel yarn structure with enhanced softness, in which the fibers were uniformly arranged. Siro false twist spun yarn was compared with a conventional siro spun yarn with the same count and twist in terms of yarn diameter, tenacity, hairiness, evenness, and packing density. The cross-sectional packing density of the yarns was analyzed based on micro X-ray computed tomography. The results showed that the siro false twist spun yarn has advantages in hairiness and evenness. The siro false twist spun yarn has an increased diameter by 10.4–19.0% and a more uniform cross-sectional packing density than the siro spun yarn. The two yarns were knitted into fabrics, and test results showed that the fabric produced with the siro false twist spun yarns had better compressibility, air permeability and light transmission. The findings from this study demonstrated that the siro false twist spun yarn improved fullness and its fabric has superior softness.