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:
Nov. 27, 2018
Filed:
Oct. 13, 2015
Sumitomo Chemical Company, Limited, Tokyo, JP;
Koichiro Watanabe, Niihama, JP;
Jian Wang, Daegu, KR;
Yasutoshi Minemoto, Niihama, JP;
Shinya Kimura, Kawasaki, JP;
Sumitomo Chemical Company, Limited, Tokyo, JP;
Abstract
Provided is a multi-layered porous film which includes a functional layer having a controlled thickness in a length-wise direction thereof and which is suitable as a separator for batteries. The multi-layered porous film includes a base film, and a functional layer containing both an inorganic filler and a binder resin, the functional layer being formed on the base film, wherein a difference between a maximum basis weight and a minimum basis weight of the multi-layered porous film in a length-wise direction thereof is equal to or smaller than 2 grams/m, the basis weight being measured every 100 meters interval. The separator fabricated by cutting a film roll comprised of a multi-layered porous film into pieces each having a given length has small lot-based fluctuation in quality, and makes it possible to fabricate a battery having a small fluctuation in quality.