Encapsulated barrier for flexible films and a method of making the same
US6911244B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2002 |
| Grant date | Jun 28, 2005 |
| Priority date | — |
| Expiry date | Dec 20, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31928
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The present invention relates to a film structure and a method of manufacturing the same. More specifically, the film structure may include a barrier material made from EVOH, nylon or other thermally sensitive barrier material encapsulated by a first adhesive material. The barrier material and the first adhesive material form a barrier layer and a first set of adhesive layers when coextruded. The barrier layer and the first set of adhesive layers may be coextruded at the same or a similar temperature to form a first extrudate. The extrudate may be encapsulated by or otherwise coextruded with a second adhesive material to form a second extrudate at a higher temperature than the first extrudate that then may be formed into a flat sheet via a die. The first set of adhesive layers protects the barrier layer from high temperatures and long residence times related to the coextrusion/lamination process that may degrade the barrier layer. In addition, acid terpolymer consisting of ethylene/methyl acrylate/acrylic acid adheres a barrier material of EVOH to outer layers of the film structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.