PRODUCTION OF COMBINED POLYESTER FILAMENT YARN HAVING DIFFERENT SHRINKAGE

PROBLEM TO BE SOLVED: To provide a process for stably and efficiently producing a combined polyester filament yarn having different shrinkage and capable of imparting a woven or knit fabric with excellent silky feeling having good bulkiness, softness, drapability and stiffness by a simple direct spinning and drawing process. SOLUTION: A combined filament yarn having different shrinkage is produced from two kinds of polyesters by a direct spinning and drawing process. In the above process, a copolyester of 2,2-bis 4-(β-hydroxyethoxy)phenyl}propane and isophthalic acid is used at least as the high-shrinkage component, the polyesters are extruded in molten state through different nozzles of the same spinneret 1, the extruded fibers are solidified by cooling and collected with an oil applied to the fibers at a position under the spinneret 1 within the range of 2 m from the spinneret, and the collected fibers are taken up with a 1st godet roller 6 at a speed of