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. 03, 2000
Filed:
Jul. 31, 1998
Yukio Shinagawa, Kanagawa, JP;
Sumio Ohtani, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Minami Ashigara, JP;
Abstract
The present invention relates to a microporous membrane and a process for producing thereof, especially a microporous membrane which can be used for microfiltration, has excellent resistance to chemicals, and a process for producing thereof. The present invention provides a microporous membrane having excellent resistance to chemicals, and a microporous membrane which facilitates waste disposal, and a process for producing thereof. The microporous membrane has a bubble point value measured by the use of ethanol (by the test method of JIS K3832) falling in the range of from 10 kPa to 1000 kPa and comprises a polymer prepared by ring opening polymerization of a compound represented by chemical formula (I) or a polymer which is a ring opening polymer or ring opening copolymer represented by chemical formula (II). An example of the ring opening ring polymer or ring opening copolymer is a norbornene resin. The process for producing the microporous membrane is as follows: A polymer prepared by ring opening polymerization of a compound represented by chemical formula (I) is heated and dissolved in a solvent (a) in which the polymer is soluble, and casted to form a solution membrane, which is rapidly cooled, and extracted with a washing solvent (b) in which the polymer is insoluble to remove the solvent (a), whereby the microporous membrane having a bubble point value measured by the use of ethanol (by the test method of JIS K3832) falling in the range from 10 kPa to 1000 kPa is obtained.