Sughrue, Mion, Zinn, Macpeak, and Seas
Ultrafine fiber of an ethylene tetrafluoride copolymer and a process for producing it and a porous membrane thereof
 Ultrafine fiber of an ethylene tetrafluoride copolymer having an orientation degree (.pi.) of at least 0.6 and an average fineness of 0.0001 to 0.9 denier. A process for producing such fiber or a porous membrane thereof is also disclosed. 
Kureha Kagaku Kogyo Kabushiki Kaisha
D Y Y D
D01F Y10T Y10S D01F
inventional additional additional inventional
Shigeru Toshiya Naohiro Nobuhiro
Saitoh Mizuno Murayama Moriyama