Polypropylene film structure having increased life time
US11591444B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2017 |
| Grant date | Feb 28, 2023 |
| Priority date | — |
| Expiry date | Jul 16, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01B3/441
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention refers to a structure comprising a biaxially oriented polypropylene (BOPP) film having at least one layer comprising a homopolymer of propylene which layer is in contact with an oil phase, the homopolymer of propylene has a) a content of isotactic pentads in the range from 95% to 98%, and b) a content of ash of not more than 30 ppm, based on the total weight of the homopolymer of propylene, characterized in that the oil phase has an absorbance value of ≤0.1, relative to the pure oil, as determined spectrophotometrically at a wavelength of 860 nm by the reduction of transmitted light intensity. The present invention further refers to the use of a biaxially oriented polypropylene (BOPP) film for making capacitors comprising said structure, wherein the oil phase has an absorbance value of ≤0.1, relative to the pure oil, as determined spectrophotometrically at a wavelength of 860 nm by the reduction of transmitted light intensity as well as the use of the homopolymer of propylene for increasing the life time of a capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.