Preparation of flexible copper foil/polyimide laminate
US7459047B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2005 |
| Grant date | Dec 2, 2008 |
| Priority date | — |
| Expiry date | Jun 8, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31681
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A flexible metal foil/polyimide laminate is prepared by applying a polyamic acid varnish onto a very thin copper foil on a carrier, semi-drying the varnish, laminating a polyimide film to the varnish-coated copper foil using a hot roll press, and heat treating the laminate for solvent removal and imidization in an atmosphere having a controlled oxygen concentration. A polyimide adhesive layer resulting from the imidization of polyamic acid has a thickness of up to 6 μm, the sum of the thicknesses of the polyimide film and the polyimide adhesive layer is up to 25 μm. The polyimide adhesive layer has a Tg>400° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.