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. 01, 2003
Filed:
May. 17, 2000
LG Chemical Ltd., Seoul, KR;
Abstract
A method of producing a microporous membrane comprising the steps of: extruding a polymer at a temperature of from (polymer melting point +10° C.) to (polymer melting point +100° C.); drawing the extruded polymer at a rate of 5˜120 m/min in 10˜150° C. to obtain a polymer film; annealing the polymer film at a temperature of from (polymer melting point −100° C.) to (polymer melting point −5° C.) for 10 seconds to 1 hour; irradiating both surfaces of the annealed polymer film with an ion-particle amount of 10 ˜10 ion/cm energized at 10 ˜10 KeV, at an irradiating distance of 5˜100 cm under a vacuum of 10 ˜10 torr; cold stretching the irradiated polymer film at a temperature of from −20° C. to (polymer melting point −40° C.); hot stretching the cold stretched polymer film at a temperature of from (polymer melting point −40° C.) to (polymer melting point −5° C.); and heat setting the hot stretched polymer film at a temperature of from (polymer melting point −80° C.) to (polymer melting point −5° C.).