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:
Jun. 07, 2013
Toray Battery Separator Film Co., Ltd., Nasushiobara, JP;
Abstract
A process of producing a membrane includes extruding diluent and polymer to form an extrudate, the polymer includes a first polyethylene having an Mw<1.0×10, a second polyethylene having an Mw≧1.0×10, and a polypropylene having an Mw≧5.0×10and a ΔHm≧80.0 J/g; wherein the sum of the polypropylene having an Mw≧5.0×10and a ΔHm≧80.0 J/g and the second polyethylene is ≧15.0 wt. % and processing the extrudate into a membrane having a thickness ≦12.0 μm by stretching the extrudate in at least one planar direction at about 108.0 to 116.0° C. after removing the solvent to a magnification factor of ≦1.1 and excludes any stretching of the extrudate after removing the solvent at a magnification factor or >1.1 and removing at least a portion of the diluent from the extrudate.