Analysis of Fiber Drawing in Wet Spinning for Surface Roughness

Engineering Research Laboratories, KANEKA CORPORATION, 1-8, Miyamaecho, Takasagocho, Takasago, Hyogo, 676-8688, Japan

^* Corresponding author: Yuta.Fukui@kaneka.co.jp

Abstract

The drawing process behavior was investigated with focus on fiber stretching speed (spinning acceleration) to improve luster quality of fibers. Wet spinning method has a limitation of low luster at high spinning speed. It was determined that (1) luster quality could be evaluated by arithmetic average (RΔa) of fibers, which indicated the roughness, and (2) the roughness of the fiber was related to the spinning acceleration through the analysis of RΔa. Spinning acceleration was measured by chasing markers that were used to tie fibers. Regardless of the length of spinning bath, fibers were mainly stretched during the first stretching stage. Therefore, a multistep drawing method was used. In the case where the drawing ratio was 220% by one-step, RΔa was 10.1°; however by multi-step drawing (1^st and 2^nd drawing ratios were 148.3%), RΔa decreased to 8.3°. The multi-step drawing method enabled the reduction in fiber roughness by preventing a sudden change in fiber stress. In addition, high temperatures improved the fiber roughness. At high temperatures, roughness decreased despite the high acceleration because the fiber was easier to stretch than at low temperatures.