Flexible wrapping material and method of manufacture
US4421823A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1982 |
| Grant date | Dec 20, 1983 |
| Priority date | — |
| Expiry date | Jun 1, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31935
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A flexible wrapping material comprising a film laminate is provided for packaging of food products which is resistant to flex-cracking and pinhole development, is impervious to liquids and gasses, and exhibits the property of grease-resistance without the use of adhesives to promote bonds between the layers. The film laminate consists of an outer layer of heat-set, biaxially oriented polymeric material followed by a layer of polymeric material, a layer of oxygen barrier polymer, a layer of biaxially oriented polypropylene, a special grease-resistant polymer, and an inner layer of heat-sealable polymeric material. The film laminate is made by bonding the outer surface layer of heat-set, biaxially oriented polymer to a substrate in which an oxygen barrier material is carried on a biaxially oriented polypropylene/special grease-resistant polymer by means of an intermediate layer of polymeric material. A layer of heat-sealable polymeric material is then extrusion-coated on the special polymer surface to form the inner layer of the laminate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.