BULKED YARN

摘要

A bulked multifilament yarn having filaments of polymeric material has alternating points of maximum polymeric density and minimum polymeric density occurring along the length of each filament with a maximum spacing of 10 metres. The yarn may have a crimped structure in which the crimps are of undulating form with more than 50% of the filaments hiving maximum amplitudes of undulation less than the diameter of the yarn and more than 50% of each filament lies on one side of a diametral plane of the yarn particular to that filament. A process of producing the yarn includes the steps of jet bulking yarn and projecting it against one end of an elongated package during which the pressure prevailing at scald one end of the package fluctuates. The pressure varies between a maximum value and a minimum value with a frequency related to the rate of feed of the yarn.