Elastic nonwoven cloth and fiber product

Abstract

To provide an elastic nonwoven cloth that is excellent in elastic recovery property and has pleasant texture without stickiness, and a fiber product using the elastic nonwoven cloth, by an elastic nonwoven cloth containing fibers that are spun at a spinning speed of from 500 to 2,500 m/min and contain a low crystalline polypropylene that satisfies (a) [mmmm]=20 to 60% by mol, (b) [rrrr]/(1−[mmmm])≦0.1, (c) [rmrm]>2.5% by mol, (d) [mm]×[rr]/[mr] 2 ≦2.0, (e) weight average molecular weight (Mw)=10,000 to 200,000, and (f) molecular weight distribution (Mw/Mn)<4, and a fiber product using the elastic nonwoven cloth.

1 . An elastic nonwoven cloth, comprising fibers that are spun at a spinning speed of from 500 to 2,500 m/min, said fibers comprising a low crystalline polypropylene satisfying the following properties:
 (a) a mesopentad fraction [mmmm]=20 to 60% by mol;   (b) [rrrr]/(1−[mmmm])≦0.1, where [rrrr] is a racemic pentad fraction;   (c) a racemic-meso-racemic-meso pentad fraction [rmrm]>2.5% by mol;   (d) [mm]×[rr]/[mr] 2 <2.0, wherein [mm], [rr] and [mr] are triad fractions;   (e) a weight average molecular weight (Mw)=10,000 to 200,000; and   (f) a molecular weight distribution (Mw/Mn)<4.   
     
     
         2 . The elastic nonwoven cloth according to  claim 1 , wherein the fibers are core-sheath composite fibers. 
     
     
         3 . The elastic nonwoven cloth according to  claim 2 , wherein the core-sheath composite fibers comprise a sheath component comprising an olefin polymer, and a core component comprising from 90 to 100% by mass of a low crystalline polypropylene, said core component comprising the low crystalline polypropylene in a larger proportion than the sheath component. 
     
     
         4 . The elastic nonwoven cloth according to  claim 2 , wherein the core-sheath composite fibers have a total low crystalline polypropylene content calculated by the following expression of from 90 to 99% by mass:
   total low crystalline polypropylene content (%)=( Ws×Xs+Wc×Xc )/100   wherein   Ws represents a mass fraction of the sheath component,   Wc represents a mass fraction of the core component,   Xs represents a mass fraction of the low crystalline polypropylene in the sheath component, and   Xc represents a mass fraction of the low crystalline polypropylene in the core component.   
     
     
         5 . A fiber product comprising the elastic nonwoven cloth according to  claim 1 . 
     
     
         6 . The elastic nonwoven cloth according to  claim 3 , wherein the core-sheath composite fibers have a total low crystalline polypropylene content calculated by the following expression of from 90 to 99% by mass:
   total low crystalline polypropylene content (%)=( Ws×Xs+Wc×Xc )/100,   wherein   Ws represents a mass fraction of the sheath component,   Wc represents a mass fraction of the core component,   Xs represents a mass fraction of the low crystalline polypropylene in the sheath component, and   Xc represents a mass fraction of the low crystalline polypropylene in the core component.