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. 14, 2017
Filed:
Jun. 04, 2013
Mitsubishi Chemical Corporation, Chiyoda-ku, JP;
Hiroto Yamada, Ogaki, JP;
Tomoyuki Nemoto, Nagahama, JP;
MITSUBISHI CHEMICAL CORPORATION, Chiyoda-ku, JP;
Abstract
There is provided a multilayer porous film that includes a covering layer formed from a coating liquid on at least one surface of a porous film. The coating liquid has high stability and coatability. The covering layer does not decrease the intrinsic high air permeability of the porous film and has high heat resistance and adhesiveness. The multilayer porous film has excellent handleability as a battery separator without causing curling. The multilayer porous film includes the covering layer on at least one surface of a porous polyolefin resin film. The covering layer is formed from a coating liquid and contains a filler and a resin binder. The multilayer porous film satisfies the following conditions 1) and 2): 1) the filler has an average circularity of 0.3 or more and less than 0.7; and 2) an acid component in the coating liquid has a first acid dissociation constant of 5 or less and has no second acid dissociation constant or a second acid dissociation constant of 7 or more in a dilute aqueous solution at 25° C.