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. 03, 1998
Filed:
Jan. 21, 1997
Yoshio Oka, Osaka, JP;
Takafumi Uemiya, Osaka, JP;
Takeshi Sakamoto, Osaka, JP;
Akira Harada, Osaka, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A separator film for a battery is formed as a hydrophilized porous biaxially oriented film. The porous biaxially oriented film has a porosity of at least about 70%, a thickness in the range of about 10 to about 500 .mu.m, and a pore size in the range of about 0.01 to about 20 .mu.m. The porous film is made of hydrophobic resin, and a hydrophilic high polymer which is fixed in the pores of the film. The hydrophilic high polymer may be heterogeneously distributed in the porous film, so that the separator film has a hydrophilic portion and a hydrophobic portion. The porosity and/or the pore size of the porous film can be varied in the direction of film thickness. The separator film is applied in an alkaline storage battery or a nonaqueous electrolyte battery such as a lithium battery.