| abstract |
A method for producing a polyester-based combined filament yarn, which comprises providing a blend of a polyester with 0.3 to 5.0 wt % based on the polyester of a different type of polymer from polyester, melt-extruding the blend from one pack to form multifilaments, cooling them below the glass transition temperature thereof, dividing them into two groups, subjecting one of the groups to a noncontacting heat treatment in an atmosphere of 120 °C or higher in an opened state of filaments, with the other group being not treated with heat, and then taking off both groups of multifilaments simultaneously at a rate of 2500 m/min followed by combining them to produce a yarn. |