Patent US4505969A successfully refreshed from Google Patents.
US4505969A
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US
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Oriented polypropylene with linear low density poly-ethylene copolymer coating
Assignee: Mobil Oil AS
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Filing: 1982-02-09
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Granted: 1985-03-19
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Expires: 2002-02-09
Abstract
Abstract The present invention relates to heat sealable laminar thermoplastic films which may be heat sealed over a wide range of temperatures. The resultant heat seals exhibit a high heat seal strength. Such laminar structures comprise at least two layers of thermoplastic film, one of the layers being an oriented base layer and the other layer a heat sealable skin layer. Preferably the base layer is an alpha olefin such as polypropylene or copolymers thereof and the skin layer is preferably a linear, low-density polyethylene copolymer, comprising ethylene which has been copolymerized with another alpha olefin in the presence of a stereospecific catalyst.
Inventors
- 👤 Milton L. Weiner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:33
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/32; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
93 words
An oriented laminar thermoplastic film comprising a base layer consisting essentially of polypropylene having at least one side thereof coated with an extruded layer consisting of a linear low density copolymer of ethylene and octene-1, siad copolymer having at least 90% by weight of ethylene and a density of from about 0.900 up to about 0.925, wherein said film is prepared by extrusion coating a layer of said copolymer onto at least one surface of a sheet of machine direction oriented polypropylene and then orienting the resultant multilayer sheet in the transverse direction.
Claim 2
Dependent Claim
93 words
An oriented laminar thermoplastic film comprising a base layer consisting essentially of polypropylene having at least one side thereof coated with an extruded layer consisting of a linear low density copolymer of ethylene and octene-1, siad copolymer having at least 90% by weight of ethylene and a density of from about 0.900 up to about 0.925, wherein said film is prepared by extrusion coating a layer of said copolymer onto at least one surface of a sheet of machine direction oriented polypropylene and then orienting the resultant multilayer sheet in the transverse direction.
Claim 3
Dependent Claim
31 words
A laminar thermoplastic film in accordance with claim 1 wherein said layer of said copolymer comprises from about 2% up to about 10% of the total thickness of said laminar film.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-18 | 1988-09-17 | 1989-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-18 | 1992-09-17 | 1993-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-18 | 1996-09-17 | 1997-03-19 | $7700.00 | Window Closed / Lapsed |