PURPOSE: To obtain the titled yarn having stress peak temperature of dry heat shrinkage stress curve and double refractive index in specific ranges, showing excellent false twisting processing, providing processed yarn having improved heat resistance, high strength, high expanding and contracting properties and elongation, mainly comprising polytetramethylene adipamide.
CONSTITUTION: Yarn for false twisting, comprising polytetramethylene adipamide having 2.6W5.0 relative viscosity and optionally containing ≤30mol% other polyamides (e.g. polycapramide, etc.), having 105W240°C stress peak temperature of dry heat shrinkage stress curve (0.3g/d initial load) and ≥50×10-3 double refractive index. The yarn, for example, is obtained by selecting spinning and drawing conditions in such a way that the stress peak temperature of dry heat shrinkage stress curve and the double refractive index are given values when undrawn yarn which was spun, cooled and solidified is drawn and heat-treated at 90W200°C.
NANJO SADAMI
MIWA MASAHIKO
| JPS61108736A | 1986-05-27 | |||
| JPS5843484A | 1983-03-14 |