| 摘要 |
PURPOSE: To stably obtain at a low cost, the subject fiber with soft touch free from sliminess thereon, having excellent touch feeling. CONSTITUTION: The fibrillated polyester fiber, which has curved flat section <=5μm in shorter side length and axially oriented continuous striae at intervals of 0.1-5μm throughout the fiber surface and lies at least partly split at the striae into ultrafine fibers each <=5μm in diameter, is obtained by the following process: a polyester containing 0.5-5wt.% of an organosulfonic acid metal salt of formula R-SO3 M is spun via a spinneret with the orifice of curved slit, cooled once to a temperature at or below the glass transition point of the polyester, and then allowed to travel through a hot zone at temperatures at or higher than the glass transition point but lower than the melting point, and wound up at a speed of 3500-6000m/min, and the resultant fiber is subjected to dry heat treatment at >=120 deg.C for >=10 s and then put to caustic reduction treatment >=10wt.% in reduction rate. |
