Laminated polypropylene film
US4675247A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1984 |
| Grant date | Jun 23, 1987 |
| Priority date | — |
| Expiry date | Dec 24, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31913
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A laminated polypropylene film consisting of a crystalline polypropylene layer having laminated to at least one side thereof a copolymer layer, said copolymer being a random copolymer of propylene and an .alpha.-olefin having 4 or more carbon atoms or a random copolymer of propylene, an .alpha.-olefin having 4 or more carbon atoms and ethylene obtained by vapor phase polymerization in the substantial absence of a liquid medium and satisfying the following conditions (1) to (4): PA1 (1) the content of an .alpha.-olefin having 4 or more carbon atoms in the copolymer is 8 to 25 mole %, PA1 (2) the content of ethylene in the copolymer is 3 mole % or less, PA1 (3) the content of a cold xylene-soluble portion in the copolymer is 15 to 60% by weight, and PA1 (4) the content of a boiling n-heptane-insoluble portion in the copolymer is 7% by weight or more. Said laminated film has an excellent low-temperature heat-sealability, an excellent transparency, a low blocking and a good scratch resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.