Biaxially oriented polypropylene film with improved breakdown strength
US11851552B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2019 |
| Grant date | Dec 26, 2023 |
| Priority date | — |
| Expiry date | Jul 23, 2040 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2205/03
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The present invention is directed to a biaxially oriented polypropylene (BOPP) film with improved breakdown strength and to a capacitor comprising an insulation film comprising a layer of the biaxially oriented polypropylene film of the present invention. The present invention is further directed to a process for producing a biaxially oriented polypropylene film. Finally, the present invention is further directed to the use of a biaxially oriented polypropylene film of the present invention as layer of an insulation film of a capacitor. The BOPP film comprises a polypropylene composition, wherein the polypropylene composition comprises a high isotactic homopolymer of propylene and a polymeric α-nucleating agent. The BOPP film has a dielectric breakdown field strength Eb63.2 of at least 595 kV/mm. The process for producing a biaxially oriented polypropylene film comprises the steps of extruding a polypropylene composition to a flat film and orienting the flat film simultaneously in the machine direction and in the transverse direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.