Oriented multilayer polyolefin films
US6638637B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 22, 2001 |
| Grant date | Oct 28, 2003 |
| Priority date | — |
| Expiry date | Aug 3, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31913
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A multi-layered biaxially oriented film comprising at least one primary layer and at least one secondary layer, wherein the primary layer comprises a propylene copolymer having a first melting point and the secondary layer comprises a polypropylene homopolymer or copolymer having a second melting point, such that the second melting point is greater than the first melting point and the multi-layered construction is biaxially stretched. The multi-layered film further includes a surface finishing layer, to provide a writable multi-layered film. This stretched film exhibits a refractive index in the machine direction (MD) that is greater than the refractive index measured in the transverse direction (TD).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.