Patent ID: 7571594

Claim:
A process for producing a composite yarn, the process comprising the steps of: (a) providing at least a first yarn comprised of polyethylene terephthalate and a second yarn comprised of polyethylene terephthalate, the first yarn having a length and a perimeter, and at least one of the first and second yarns being a heat-shrinkable yarn exhibiting a shrinkage upon exposure to heat of about 20% or more, (b) providing a rotary, hollow spindle assembly, (c) providing a heater assembly, (d) providing a yarn collection assembly, (e) passing the first and second yarns through the spindle assembly so that the second yarn is wrapped around the perimeter of and along at least a portion of the length of the first yarn, the wrapped first and second yarns forming a yarn intermediate, (f) overfeeding the yarn intermediate to the heater assembly and exposing the yarn intermediate to heat sufficient to at least partially shrink the heat-shrinkable yarn and thereby produce a polyethylene terephthalate composite yarn, wherein the yarn intermediate is overfed to the heater assembly at an overfeed rate of at least about 20%, and (g) collecting the polyethylene terephthalate composite yarn on the yarn collection assembly, the yarn composite being collected such that substantially no tension is applied to the polyethylene terephthalate composite yarn during collection.