Method for producing polyester wool-like yarn

Claim 1

A process for producing a self-crimping yarn comprising first and second types of filaments, said process comprising: (a) spinning said first of filament type by (1) forming a first plurality of melt spun filaments by merging molten polyester streams traveling at different extrusion speeds to form thick and thin regions in the merged streams out of phase from other merged streams; (2) quenching said first plurality of merged streams into said first type of filaments having thick and thin regions along their lengths and out of phase from filament to filament; (b) spinning said second of filament type by (1) extruding other streams of molten polymer of fiber forming molecular weight from helical orifices selected to give filaments with helical cross-sections and lower shrinkages than said combined filaments at a given common spinning speed; and (2) quenching said other streams into filaments; (c) withdrawing said first and said second types of filaments from said streams at said common spinning speed; and (d) combining said first and said second types of filaments into a yarn; (e) said thick and thin regions in said first plurality of molten streams and said common spinning speed being selected such that said yarn has a crimp of at least 2%.