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:
Oct. 09, 2018
Filed:
Feb. 10, 2015
Oji Holdings Corporation, Tokyo, JP;
Tatsuji Ishida, Konan, JP;
Masahiro Nakata, Konan, JP;
Tadakazu Ishiwata, Chiba, JP;
Akihiro Kakehi, Kusatsu, JP;
Yoshinori Matsuo, Saitama, JP;
Masahiro Yoda, Konan, JP;
OJI HOLDINGS CORPORATION, Tokyo, JP;
Abstract
The present invention addresses the problem of providing a biaxially stretched polypropylene film for capacitors, which has high voltage resistance and excellent breakdown properties. The present invention also addresses the problem of providing a biaxially stretched polypropylene film for capacitors, which can be used suitably in a high-capacity capacitor to which a high voltage is to be applied under a higher temperature, and which preferably has a small thickness. The present invention relates to a bi-axially stretched polypropylene film for capacitors, wherein a polypropylene resin which constitutes the polypropylene film has a number average molecular weight of 40,000 to 100,000 inclusive and a Z average molecular weight of 950,000 to 1,500,000 inclusive, wherein, in a molecular weight distribution curve, the value of the difference obtained by subtracting a differential distribution value at a logarithmic molecular weight Log (M) of 6.0 from a differential distribution value at a logarithmic molecular weight Log (M) of 4.5 is −15 to 11% inclusive.