McDermott, Will & Emery
Polypropylene fiber, a method for manufacture thereof, and a non-woven fabric made of the same
 There is disclosed a polypropylene fiber which is suitable for hot rolling and which is used for producing a non-woven fabric having high tenacity and good feel by heat rolling within a wide range of processing temperatures. A polypropylene fiber contains boiling n-heptane extract in the amount of 1.5 to 5 percent by weight after extraction with boiling n-hexane, and the extract has a melting point peak of 140.degree. C. or higher. 
Chisso Corporation
D D Y D Y Y
D01F D04H Y10T D01F Y10T Y10T
inventional inventional additional inventional additional additional
Hidemi Masahiko Yoshimi
Ito Taniguchi Tsujiyama