Composite elastic yarn, stretchable fabric, and method for manufacturing composite elastic yarn

Abstract

The present invention is directed to a composite elastic yarn, including a core section including an elastic core filament, and a sheath section including staple fibers surrounding the core section, wherein the elastic core filament has a low cohesion property in which the inter-filament cohesion thereof is within the range of 9 to 198 mg when measured according to the ASTM D3822 method, and is also directed to a fabric, and a method for manufacturing a composite elastic yarn. According to the present invention, it is possible to solve a puckering problem occurring on the surface of a denim fabric, thereby improving a touch sensation and the quality of a final product.

1 . A composite elastic yarn comprising a core section including an elastic core filament, and a sheath section including staple fibers surrounding the core section, wherein the elastic core filament has a low cohesion property in which inter-filament cohesion thereof is within a range of 9 to 198 mg when measured according to an ASTM D3822 method. 
     
     
         2 . The composite elastic yarn of  claim 1 , wherein the elastic core filament has an inter-filament cohesion corresponding to 1.5 to 22% of an inter-filament cohesion of a general-purpose elastic core filament of a same fineness. 
     
     
         3 . The composite elastic yarn of  claim 1 , wherein the core section is made of polyurethane, polyurethane-urea, or a blend of polyurethane and polyurethane-urea. 
     
     
         4 . The composite elastic yarn of  claim 1 , wherein the sheath section is selected from the group consisting of wool, linen, silk, polyester, nylon, olefin, cotton, Tencel, Modal, poly-viscose, and combinations thereof. 
     
     
         5 . The composite elastic yarn of  claim 1 , wherein the core yarn has a fineness of 40 to 120 denier. 
     
     
         6 . The composite elastic yarn of  claim 1 , wherein the elastic core filament is prepared by being interlaced twice before being wound and being air-interlaced at a pressure and temperature lower than those of the primary interlacing step in the secondary interlacing. 
     
     
         7 . A fabric in which at least one of warp and weft yarns comprises a composite elastic yarn, including a core section including an elastic core filament and a sheath section including staple fibers surrounding the core section, wherein the elastic core filament has a low cohesion property in which inter-filament cohesion thereof is within a range of 9 to 198 mg when measured according to an ASTM D3822 method. 
     
     
         8 . A method for manufacturing a composite elastic yarn, the method comprising: after an elastic core filament yarn has been spun, preparing a low-cohesion core yarn by primarily interlacing the elastic core filament yarn so that inter-filament cohesion thereof is 500 to 1500 mg, secondarily interlacing the primarily interlaced elastic core filament yarn so that inter-filament cohesion thereof is 9 to 198 mg, and then winding the interlaced elastic core filament yarn; and coating the low-cohesion core yarn, prepared in a previous step, with a staple fiber roving yarn and then spinning the coated low-cohesion core yarn. 
     
     
         9 . The method of  claim 8 , wherein the method comprises performing the primary interlacing via a first interlace nozzle at an air flow rate of 3 to 4 L/min and a temperature of 35 to 30° C. and then performing the secondary interlacing via a second interlace nozzle at an air flow rate of 1 to 2 L/min and a temperature of 15 to 20° C. 
     
     
         10 . The method of  claim 8 , wherein the elastic core filament is prepared to have an inter-filament cohesion corresponding to 1.5 to 22% of an inter-filament cohesion of a general-purpose elastic core filament of a same fineness.