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:
Apr. 29, 2014
Filed:
Jan. 10, 2007
Akihiro Ariji, Shiga, JP;
Hideki Yamada, Osaka, JP;
Akihiro Ariji, Shiga, JP;
Hideki Yamada, Osaka, JP;
Toyo Boseki Kabushiki Kaisha, Osaka, JP;
Abstract
This disclosure relates to an anisotropic polyvinylidene fluoride hollow fiber microporous membrane containing a polyvinylidene fluoride resin. The hollow fiber microporous membrane does not include macrovoids, and has mainly a net-like structure. In addition, the hollow fiber microporous membrane has a dense outer layer on an outer surface, and a homogeneous bulk layer that is internally adjacent to the outer layer and has a coarser structure than the outer layer. The porosity of the bulk layer is at least 1.5 times the membrane surface porosity of the outer layer. The dense structure of the outer layer changes substantially discontinuously into the coarse structure of the bulk layer.