Polyimide films and electronic devices
US11603440B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 2020 |
| Grant date | Mar 14, 2023 |
| Priority date | — |
| Expiry date | Dec 12, 2040 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K2003/2244
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
In a first aspect, a polyimide film includes a dianhydride and a diamine. The dianhydride, the diamine or both the dianhydride and the diamine include an alicyclic monomer, an aliphatic monomer or both an alicyclic monomer and an aliphatic monomer. The polyimide film has a b* of 1.25 or less and a yellowness index of 2.25 or less for a film thickness of 50 μm. The polyimide film is formed by: (a) polymerizing the dianhydride and the diamine in the presence of a first solvent to obtain a polyamic acid solution; (b) imidizing the polyamic acid solution to form a substantially imidized solution; (c) casting the substantially imidized solution to form a film; and (d) drying the film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.