Multi-layer barrier film
US4239826A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1978 |
| Grant date | Dec 16, 1980 |
| Priority date | — |
| Expiry date | Dec 28, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31935
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A delamination resistant multi-layer film comprises a core layer of vinyl alcohol polymers or copolymers such as polyvinyl alcohol or ethylene vinyl alcohol. Adhered to the core layer are one or more layers of a partially hydrolyzed vinyl acetate polymer or copolymer having functional groups in the polymer such that strong adhesion to the core layer is obtained. The core layer provides an excellent oxygen barrier, while the adjacent layers protect the core layer from degradation by exposure to water vapor. Additional layers of various polymer materials may be provided over the layers of partially hydrolyzed vinyl acetate. The film can be prepared by coextrusion techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.