Sealable polyolefin films containing very low density ethylene copolymers
US5206075A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 19, 1991 |
| Grant date | Apr 27, 1993 |
| Priority date | — |
| Expiry date | Dec 19, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31913
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The invention provides laminar polyolefin film materials having a base film layer comprising a blend of an olefin polymer and up to about 30% by weight of at least one very low density copolymer of ethylene and a C.sub.3 to C.sub.20 alpha olefin comonomer copolymerizable with ethylene, said base layer having a heat sealable film layer present on one or both surfaces thereof comprising a very low density copolymer of ethylene and a copolymerizable C.sub.5 to C.sub.12 alpha olefin comonomer. The ethylene copolymer constituents of the film are characterized as having a density in the range of about 0.88 g/cm.sup.3 to abut 0.915 g/cm.sup.3, a melt index in the range of about 0.5 dg/min to about 7.5 dg/min, a molecular weight distribution (M.sub.w /M.sub.n) of about 1.5 to about 3.5 and an essentially single melting point in the range of about 60.degree. C. to about 115.degree. C., measured as a DSC peak T.sub.m. Films of this invention exhibit extremely good hot tack seal strength at temperatures in the range of from about 200.degree. to 290.degree. F. thereby rendering them extremely useful as packaging materials in high speed packaging operations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.