Abstract
Factors affecting the surface shape of a hard-twist-yarn fabric were experimentally examined in terms of the weaving and heat-set conditions, and particularly the crystallinity of the original fibers. The results obtained are as follows:
(1) The number of ribs increases in proportion to the torque which remains after the twist set was given to the yarns; the increasing rate is high (or low) at the set temperature higher (or lower) than the annealing temperature of the original yarns.
(2) The height of ribs depends on the torque and shrinking force generated in the yarns when the fabrics are scoured.
(3) The higher the crystallinity of the fibers, the larger the yarn torque is. This gives rise to a large number of thinner ribs.
(4) The number of ribs increases and the rib height decreases with increasing twisting tension of the yarn. The rib height also increases with increasing twist-set tension applied to yarns.
