Soft and stretchable textile fabrics made from polytrimethylene terephthalate

Abstract

In this invention, we found unexpectedly that when PTT fiber is drawn,textured and set under certain conditions, the fabrics made from textured fibers by this texturing process possess stretch and hand which is much better than current commercially available PBT and PET stretch fabrics, and better than PTT textured fibers made under similar conditions without the setting step. Specifically, the invention describes the spinning of PTT polymer into yarn with an elongation of 60 to 160% and draw-texturing the yarn using a false-twist draw-textured yarn machine at a draw ratio of 1.02 to 1.6 and a yarn temperature of 120 to 160° C., preferably 130 to 150° C. The yarn is further set, usually with a secondary heater, at a yarn temperature of 70 to 130° C., preferably 85 to 115° C., prior to winding. Then knitted fabrics are dyed, tentor-set, and finished with fabric softener. This invention is different from the above teachings in that the PTT yarn is draw-textured in a false-twist machine. The yarn is crimped (textured) at a much lower first heater temperature of 130 to 160° C. than described in the above prior art, is set with a secondary heater at 70 to 130° C. Fabrics made from the set yarn have as good or better stretch and better hand than fabrics made from the un-set yarn.

We claim:  
     
         1 . A process of making a stretch fabric with excellent hand from polytrimethylene terephthalate which comprise: 
 (a) spinning a polytrimethylene terephthalate polymer into a partially oriented yarn with elongation of 60 to 150%,    (b) draw-texturing the yarn in a false-twist draw-texturing machine at a draw ratio of 1.02 to 1.6, and a yarn temperature of 120 to 160° C., and    (c) heat setting the draw-textured yarn at a yarn temperature of 70 to 130° C.    
     
     
         2 . The process of  claim 1  wherein the draw-texturing temperature is from 130 to 150° C. and the second heat set temperature is from 85 to 115° C.  
     
     
         3 . The process of  claim 1  wherein the draw-texturing is carried out at a draw ratio of from 1.05 to 1.4.  
     
     
         4 . A process of making a stretch fabric with excellent hand from polytrimethylene terephthalate which comprise: 
 (a) spinning a polytrimethylene terephthalate polymer yarn and drawing it in-situ using heated godets to a final elongation of 60 to 150%,    (b) draw-texturing the yarn in a false-twist draw-texturing machine at a draw ratio of 1.02 to 1.6, and a yarn temperature of 120 to 160° C., and    (c) heat setting the draw-textured yarn at a yarn temperature of 70 to 130° C.    
     
     
         5 . The process of  claim 4  wherein the draw-texturing temperature is from 130 to 150° C. and the second heat set temperature is from 85 to 115° C.  
     
     
         6 . The process of  claim 4  wherein the draw-texturing is carried out at a draw ratio of from 1.05 to 1.4.