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:
May. 19, 2026
Filed:
Sep. 16, 2022
Toray Industries, Inc., Tokyo, JP;
Toshiumi Tatsuki, Otsu, JP;
Masatoshi Ohkura, Otsu, JP;
Toray Industries, Inc., Tokyo, JP;
Abstract
This film for film capacitors has two resin layers of different thicknesses, wherein, letting resin layer A be the layer with the smaller thickness and resin layer B be the layer with the larger thickness, the resin layer A is present on at least one side of the resin layer B. In addition, the film for film capacitors has an XA, which is determined using formula (i) from the atomic fractions for H, C, S, Si, N, and O in the resin layer A, of 0.050-0.80; has a loss tangent measured at 10 kHz and 23° C. of not more than 0.50%; and satisfies at least one of conditions 1 and 2.XA=(atomic fraction for C+atomic fraction for N+atomic fraction for S+atomic fraction for Si)/(atomic fraction for H+atomic fraction for O). Formula (i) Condition 1: The melting point measured by DSC is at least 180° C. Condition 2: The glass transition temperature measured by DSC is at least 130° C. and not more than 370° C. Provided is a film for film capacitors that has a high heat resistance and self-healing performance and that can reduce the decline in properties induced by heating when used in a capacitor.