Stretch yarns and fabrics with multiple elastic yarns

Abstract

Included herein are articles and methods including a core spun yarn. The core spun yarn includes a sheath of hard fibers and two sets of elastic fibers wherein the sets of elastic fibers have different properties. The properties may differ in one or more ways such as having a different denier, composition or draft. One or both of the sets of elastic fibers can be pre-covered.

What is claimed is: 
     
         1 . An article comprising a core spun yarn comprising:
 a) a sheath of hard fibers;   b) an elastic core fiber I; and   c) an elastic core fiber II;
 wherein the elastic core fiber I and the elastic core fiber II have different elastic properties. 
   
     
     
         2 . The article of  claim 1 , wherein the elastic core fiber I and the elastic core fiber II have different deniers or different filaments. 
     
     
         3 . The article of  claim 1 , wherein the elastic core fiber I and the elastic core fiber II have different drafts. 
     
     
         4 . The article of  claim 1 , wherein the elastic core fiber I and the elastic core fiber II have different polymer compositions. 
     
     
         5 . The article of  claim 1 , wherein at least one elastic core fiber comprises elastomeric fiber having denier of about 10 denier to about 450 denier. 
     
     
         6 . The article of  claim 5 , wherein at least one elastic core fiber comprises spandex fiber. 
     
     
         7 . The article of  claim 1 , wherein at least one elastic core fiber comprises elastic polyolefin fiber having denier of about 10 denier to about 450 denier. 
     
     
         8 . The article of  claim 7 , wherein the elastic polyolefin fiber is lastol fiber. 
     
     
         9 . The article of  claim 1 , wherein at least one elastic core fiber are pre-covered elastic yarn having denier of about 15 denier to about 300 denier. 
     
     
         10 . The article of  claim 9 , wherein the pre-covered elastic yarn includes a covering selected from the group consisting of air covered yarn, single wrapped yarn and double wrapped yarn, and combinations thereof. 
     
     
         11 . The article of  claim 9 , wherein the pre-covered elastic yarn is a polyester and spandex air covered yarn. 
     
     
         12 . The article of  claim 1 , wherein at least one elastic core fiber includes a non-elastomeric elastic fiber having a denier of about 15 to about 450 denier. 
     
     
         13 . The article of  claim 12 , wherein the non-elastomeric elastic fiber comprises filaments with yarn recoverable stretch higher than 20% tested with ASTM D6720-07 method. 
     
     
         14 . The article of  claim 12  wherein said non-elastomeric elastic fiber comprises at least one fiber selected from the group consisting of polyester, nylon, PTT fiber, PBT fiber and bi-component fiber, and combinations thereof. 
     
     
         15 . The article of  claim 1 , wherein the sheath of hard fibers is selected from the group consisting of wool, linen, silk, polyester, nylon, olefin and cotton, and combinations thereof. 
     
     
         16 . An article comprising a woven fabric having warp yarns and weft yarns, wherein at least one of the warp yarns and weft yarns includes a core spun yarn comprising:
 a) a sheath of hard fibers;   b) an elastic core fiber I; and   c) an elastic core fiber II;   
       wherein the elastic core fiber I and the elastic core fiber II have different elastic properties. 
     
     
         17 . The article of  claim 16 , wherein the woven fabric has stretch in the weft direction between about 10 and about 45%. 
     
     
         18 . The article of  claim 16 , wherein the woven fabric comprises a garment. 
     
     
         19 . A method of making an article comprising a woven fabric having warp yarns and weft yarns wherein the warp yarn or weft yarn or both warp and weft yarns have core spun yarn, said method comprising covering together a core spun yarn comprising:
 a) a sheath of hard fibers;   b) an elastic core fiber I; and   c) an elastic core fiber II;
 wherein the elastic core fiber I and the elastic core fiber II have different elastic properties. 
   
     
     
         20 . A stretch fabric comprising a core spun yarn comprising:
 a) a sheath of hard fibers;   b) an elastic core fiber I; and   c) an elastic core fiber II;
 wherein the elastic core fiber I and the elastic core fiber II have different elastic properties. 
   
     
     
         21 . The stretch fabric of  claim 20 , wherein the stretch fabric is woven, warp knit, or circular knit fabric.