Patent ID: 6620504
Filing Date: 2003-09-16
Classification: D01D,D01F,D02G,D02J,Y10T

Abstract:
A thick and thin polyester multifilament yam comprising a plurality of thick and thin polyester individual filaments the thickness of which periodeally varies along the longitudinal direction thereof, wherein when the thick and thin multifilament yarn is subjected to a yam thickness variation measurement, in the normal mode test method using the Uster evenness tester, the resultant spectrogram of the thick and thin multifilament yam exhibits a first peak (Pmax1) of the coefficient of variation in yam thickness at a thickness variation period of 4 to 10 cm and a second peak (Pmax2) of the coefficient of variation in yam thickness at a thickness variation period of 50 to 150 cm, and the ratio (Pmax1/Pmax2) of the first peak coefficient of variation in the yam thickness (Pmax1) to the second peak coefficient of variation in the yam thickness (Pmax2) is in the range of from 1.0 to 4.0.