To provide a method for direct spin-drawing of polyester fiber by using multiple filaments and winding the filaments half around the roller while preventing an inequitable dyeing.
This direct spin-drawing method comprises: taking up a plurality of polyester fiber filaments cooled down and discharged from a spinneret 1 by using a roller 6 having a circumferential speed of ≥1,500 m/min. and <4,000 m/min.; subsequently drawing the filaments between rollers; and taking up them at a speed of ≥4,000 m/min., and the method further comprises winding the filaments around the take-up roller 6 less than one round; positioning a noncontact type filament yarn-heating device 5 with a direct heating medium of steam just before the roller 6; and conducting the heating without drawing the yarns in the device, wherein a temperature in the treating chamber and treatment length are set as follows: 70≤Ts≤120; and 0.05 Vs≤L≤0.15 Vs (Ts: temperature in the treating chamber, Vs: circumferential speed of the take-up roller (m/min.): and L: filament yarn length).
MIZUHASHI MOTOI
FUKUHARA MOTOTADA
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