Biaxally-oriented polypropylene films containing a non-crystallizable, amorphous polyester layer, and method of making the same
US6872458B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2002 |
| Grant date | Mar 29, 2005 |
| Priority date | — |
| Expiry date | Feb 14, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31938
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of making a multilayer film is provided, including the steps of forming a core layer of a polypropylene film, monoaxially orienting the core layer in a first direction, and providing at least one multilayer cap layer to at least one side of the core layer to provide a multilayer film. The cap layer includes a non-crystallizable, amorphous polyester layer having a sufficient proportion of a non-crystallizable, amorphous polyester to render the amorphous polyester layer non-crystallizable and a first tie layer interposed between the polyester layer and the core layer, the first tie layer including an adhesive. The multilayer film is then oriented in a second direction transverse to the first direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.