Polypropylene laminated film
US5773129A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1994 |
| Grant date | Jun 30, 1998 |
| Priority date | — |
| Expiry date | Dec 21, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31938
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polypropylene laminated film containing a crystalline polypropylene layer and, laminated on at least one side of the layer of the crystalline polypropylene, a layer of a copolymer of propylene and at least one .alpha.-olefin of from 4 to 10 carbon atoms having a specific composition, melt flow rate and molecular weight distribution in which the .alpha.-olefin content in the cold xylene soluble portion of the random copolymer is less than 1.7 times the .alpha.-olefin content in the copolymer and the random copolymer satisfies the mathematical expression, EQU B.ltoreq.1.05A-10, wherein A is a weight percentage of the content of said at least one .alpha.-olefin having from 4 to 10 carbon atoms in the random copolymer and B is a weight percentage of the cold xylene soluble portion in the random copolymer, is superior in low temperature heat sealability and hot tack property and moreover has a good transparency, blocking resistance and printability, wherein the random copolymer is obtained by gas phase polymerization substantially in the absence of a liquid medium, and using a catalyst system comprising (i) a solid catalyst component containing magnesium, titanium and a halogen as ess…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.