Spunbond nonwoven fabric

Abstract

Provided is a spunbond nonwoven fabric which is made of a polypropylene fiber and satisfies all of the following conditions A to E: A. the average single fiber diameter of the fiber is 6-17 μm; B. the degree of crystal orientation of the fiber as obtained by wide-angle X-ray diffraction is at least 0.91; C. the crystallite size of the (110) plane of the fiber as obtained by wide angle X-ray diffraction is at least 12 nm; D. the average orientation parameter of the fiber as obtained by Raman spectroscopy is at least 8.0; and E. the complex viscosity of the spunbond nonwoven fabric at a temperature of 230° C. is 20-100 Pa·sec at an angular frequency of 6.3 rad/sec.

1 . A spun-bonded nonwoven fabric comprising polypropylene fibers wherein all of the following conditions A to E are satisfied:
 A. the fibers have an average single fiber diameter of 6 μm or more and 17 μm or less;   B. the fibers have a crystal orientation degree in wide-angle X-ray diffraction of 0.91 or more;   C. the fibers have a crystallite size of a (110) plane in wide-angle X-ray diffraction of 12 nm or more;   D. the fibers have an average orientation parameter in Raman spectroscopy of 8.0 or more; and   E. the spun-bonded nonwoven fabric has a complex viscosity of 20 Pa·sec or more and 100 Pa·sec or less at a temperature of 230° C. at an angular frequency of 6.3 rad/sec.   
     
     
         2 . The spun-bonded nonwoven fabric according to  claim 1 , wherein the spun-bonded nonwoven fabric has the complex viscosity of 40 Pa·sec or more and 80 Pa·sec or less at the temperature of 230° C. at the angular frequency of 6.3 rad/sec.