The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 12, 1995
Filed:
Apr. 16, 1993
Tamiyuki Eguchi, Kobe, JP;
Kanegafuchi Kagaku Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
A porous hollow fiber of polysulfone suitable for use in filtration such as microfiltration and having a prolonged life, the hollow fiber having an inner surface with a network structure such that approximately circular openings having a minor axial length of 0.1 to 10 .mu.m are present in proximity to each other at intervals of not more than the average minor axial length of the openings, thus providing a surface fraction of openings of 50 to 90% and/or an outer surface of a structure such that the outer surface region has undergone fibrillation to a high degree to form fibrils oriented in the fiber axial direction at intervals of 0.2 to 3 .mu.m, thus providing a surface fraction of openings of at least 50%. The hollow fiber is prepared by a process characterized in that a polymer substance having an extremely high molecular weight such as polyethylene glycol and polyvinyl pyrrolidone is added to the spinning solution of polysulfone, thereby improving the spinnability.