| 摘要 |
PURPOSE:To obtain a polyester fiber, having a unique glittering gloss, untransparency and bright color developing properties and suitable as woven or knit fabric for high- class clothes by specifying the cross-sectional shape of polyester fiber, prepared by copolymerizing an isophthalic acid component containing a metallic sulfonate group and good in the color developing properties. CONSTITUTION:This polyester fiber is obtained by regulating the percentage of hollowness of the polyester fiber good in color developing properties in which 1.0-3.0mol% of recurring units are a metallic sulfonate group-containing isophthalic acid component to 10-40%, preferably 15-30% and the radius of curvature [r (mum)] of each apical part 3 in the fiber cross section to <=2 times based on the single fiber size (d) (denier) and further regulating the cross section to a polygonal hollow cross section of >=a triangular to <=a hexagonal shape (preferably a tetragonal shape) having <=10%, preferably <=8% coefficient of variation of side parts 4 between the mutually adjacent apical parts. The coefficient of variation (%) of the side parts is 100 times of a ratio (t/s) of the distance (t) between each reference line (L) drawn in each side part and a point (T) farthest from the reference line (L) to the distance (s) between the reference lines. |
