Opaque polymeric films and processes for making the same
US6194060A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1999 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Feb 18, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249993
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An opaque, oriented polymeric film structure comprises: (a) a core layer containing a thermoplastic polymeric matrix material which has a first surface and a second surface, the core layer having a plurality of voids, substantially all or all of the voids being free from a void-initiating particle and at least some of the voids being interconnected with an adjacent void in the polymeric matrix material, the number of voids not containing a void-initiating particle being sufficient to impart a significant degree of opacity to the film structure; and (b) at least one outer or skin layer containing a thermoplastic polymeric material and an effective amount of a nucleating agent to suppress cavitation in said at least one outer or skin layer. The film structure has a smooth surface and can be tailored to provide a controlled permeability, and is particularly suitable for food packaging.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.