Composition for uniaxially heat shrinkable biaxially oriented polypropylene film
US6113996A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 1997 |
| Grant date | Sep 5, 2000 |
| Priority date | — |
| Expiry date | May 19, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31913
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A uniaxially heat-shrinkable, biaxially oriented, multilayer film having a polypropylene-containing core layer comprising at least 70 wt. % of said multilayer film and optionally, at least one polyolefin-containing skin layer adjacent said core layer, is prepared by biaxially orienting a coextrudate and therefore orienting said coextrudate by stretching 10 to 40 % in the machine direction. The core layer contains isotactic polypropylene and a sufficient amount of syndiotactic polypropylene to inhibit uniaxial heat shrinkage at temperature below about 50.degree. C. The skin layer can be selected from the group consisting of polypropylene, ethylene-propylene copolymer, polyethylene, and ethylene-propylene-butylene terpolymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.