Multi-layer stretch wrapping film
US6033775A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 1997 |
| Grant date | Mar 7, 2000 |
| Priority date | — |
| Expiry date | Nov 28, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31928
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A film containing a first layer containing a propylene-based block copolymer (a) obtainable by forming 40 to 85% by weight of a propylene-ethylene copolymer portion (A) having a content of repeating unit derived from ethylene of 1.5 to 6.0% by weight in a first step, and then forming 15 to 60% by weight of a propylene-ethylene copolymer portion (B) having a content of repeating unit derived from ethylene of 7 to 17% by weight in a second step, the intrinsic viscosity of portion (B) being 2 to 5 dl/g, and the ratio of the intrinsic viscosity of portion (B) to the intrinsic viscosity of portion (A) being 0.5 to 1.8, and a second layer containing a polyethylene type resin (b) laminated on at least one surface of the first layer, has a good balance between heat resistance, flexibility, mechanical strength, transparency, cuttability, original-shape resuming property and other desirable properties, and is suitably used for wrapping materials such as foods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.