PURPOSE: The titled filamentary yarns of noncircular cross section, prepared by sticking two component fibers having a specific difference in the shrinkage in hot water or above in the longitudinal direction thereof, and having a specific stretch extension ratio in a treatment with hot water, latent crimpability and further feeling and luster similar to those of silk.
CONSTITUTION: A polyester, e.g. polyethylene terephthalate, is melt extruded through a nozzle (b) or (c) for modified cross section yarns to prepare two undrawn yarns 1 and 2 having ≥3% difference in shrinkage in hot water, which are then fed through a nip roll 3 and a feed roll 4 and drawn between a hot roll 5 and a draw roll 8. In the process, one yarn is brought into contact with a hot plate 6, and the other yarn is out of contact with the hot plate 6 with a separating guide 7. The two yarns are then drawn and doubled to give the aimed conjugate fibers of noncircular cross section having 10W75% stretch extension in the treatment with hot water and two component fibers having different shrinkages, and stuck in the longitudinal direction thereof.