Bicomponent Spunbond Fiber and Spunbond Fabric Prepared Therefrom

Abstract

Bicomponent fibers, methods of forming bicomponent fibers and articles formed from bicomponent fibers, are described herein. The bicomponent fibers generally include a sheath component and a core component, wherein the sheath component consists essentially of a first metallocene polypropylene and the core component consists essentially of a second metallocene polypropylene.

1 . A bicomponent fiber comprising:
 a sheath component and a core component, wherein the sheath component consists essentially of a first metallocene polypropylene and the core component consists essentially of a second metallocene polypropylene.   
     
     
         2 . The bicomponent fiber of  claim 1 , wherein a weight ratio of the sheath component to the core component is from about 10:90 to about 30:70. 
     
     
         3 . The bicomponent fiber of  claim 1 , wherein the sheath is formed from a propylene based random copolymer. 
     
     
         4 . The bicomponent fiber of  claim 1 , wherein the first metallocene polypropylene comprises a copolymer comprising an ethylene content of from about 0.2 wt. % to about 6 wt. % polyethylene. 
     
     
         5 . The bicomponent fiber of  claim 1 , wherein the first metallocene polypropylene comprises a copolymer comprising an ethylene content of from about 0.2 wt. % to about 1 wt. % polyethylene. 
     
     
         6 . The bicomponent fiber of  claim 1 , wherein the first metallocene polypropylene comprises a blend of a first polypropylene and a second polypropylene. 
     
     
         7 . The bicomponent fiber of  claim 1 , wherein the core is formed from a polypropylene homopolymer. 
     
     
         8 . The process of  claim 1 , wherein the first metallocene polypropylene comprises a first melting point, the second metallocene polypropylene comprises a second melting point and wherein there is difference in the first melting point and the second melting point of less than about 20° C. 
     
     
         9 . A spunbond non-woven article formed by the bicomponent fiber of  claim 1 . 
     
     
         10 . The bicomponent fiber of  claim 1 , wherein the first metallocene polypropylene exhibits a molecular weight distribution of from about 1.5 to about 8. 
     
     
         11 .- 15 . (canceled)