Two-fold self twisted textured yarn - has effect yarn twisted around core yarn

摘要

The effect (decorative) yarn (e.g. polyethylene terephthalate) is helically twisted in one direction over a given length and then helically twisted in the reverse direction for a similar length. Pref. the spacing between each convolution of helical twist is 1-4 mm, and the twist changeover zone spans 2-20 mm. Pref. the core yarn (e.g. polyethylene terephthalate or polyhexamethylene adipamide) and effect yarn are combined at a false twisting ring, the effect yarn being supplied with overfeed and being oscillated transversely at 150-200 Hz with an amplitude 10 mm.