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:
Oct. 15, 1991
Filed:
Jul. 11, 1990
Toshinobu Koshoji, Toyohashi, JP;
Hironari Honda, Toyohashi, JP;
Kiyonobu Okamura, Toyohashi, JP;
Kunio Misoo, Toyohashi, JP;
Osamu Nishimura, Toyohashi, JP;
Mitsubishi Rayon Co., Ltd., Tokyo, JP;
Abstract
Disclosed is a porous membrane comprising (1) a hydrophilic copolymer X composed principally of (poly)alkylene glycol mono(meth)acrylate units A and ethylene units B and (2) a polyolefin Y, the (poly)alkylene glycol mono(meth)acrylate units A being of the formula ##STR1## where R.sup.1 and R.sup.2 independently represent hydrogen or methyl, and n has a value in the range of 1 to 9. This porous membrane has permanent hydrophilicy suitable for the treatment of water-based liquids and can be produced by an industrially advantageous process. This process comprises melt-forming a blend of (1) a hydrophilic copolymer X composed principally of (poly)alkylene glycol mono(meth)acrylate units A and ethylene units B and (2) a polyolefin Y; heat-treating the melt-formed product in a vacuum or an inert gas medium at a temperature not higher than the melting point of polyolefin Y for a period of an hour or more; and stretching the heat-treated, melt-formed product to make it porous.