Process for dimensionally stable polyester yarn
US5085818A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1990 |
| Grant date | Feb 4, 1992 |
| Priority date | — |
| Expiry date | Jun 26, 2010 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD01F6/62
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A process for production of a dimensionally stable drawn polyethylene terephthalate multifilament yarn having filaments of at least 2.5 denier per filament comprising the steps of: PA0 a) extruding a polyethylene terephthalate polymer melt through a spinnerette having a plurality of extrusion orifices to form filaments; PA0 b) advancing the extruded multifilament yarn first through a delay zone then through a quenching zone to solidify the filaments in a controlled manner; PA0 c) withdrawing the solidified multifilament yarn from the quenching zone at a desired spinning speed V; PA0 whereby steps a) through c) are performed under conditions to form a partially-oriented multifilament yarn having a undrawn birefringence (.DELTA.n.sub.u) of at least 0.020 and wherein .DELTA.n.sub.u =R.sub.f V.sup.2.0 IV.sup.2.4 where IV is the intrinsic viscosity of the undrawn yarn and is at least 0.80 and R.sub.f is at least 9.0.times.10.sup.-3 ; then PA0 d) hot drawing the partially-oriented multifilament yarn. The process permits production of high undrawn birefringence yanrs at lower speeds and lower IV's than previously demonstrated in the prior art.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.