US4303709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coextruded laminar thermoplastic bags
Assignee: Pactiv LLC
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Filing: 1979-12-14
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Granted: 1981-12-01
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Expires: 1999-12-14
Abstract
Abstract A thermoplastic bag particularly adapted for the containment and storage of foods comprising a laminar bag structure having an interior layer of a high density polyethylene copolymer and an exterior layer of polypropylene. The layers are intimately and continuously bonded together at their interface. Such bag structures are suitable for the containment of foodstuffs while they are being heated or reheated following storage.
Inventors
- 👤 Robert H. Olson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:29
CPC Classifications
B; B65; B65D; B65D31/00; B65D31/02; B32; B32B; B32B27/00; B32B27/32; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1334; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
75 words
A two-layer coextruded, thermoplastic laminar bag construction particularly suitable for the containment of food which has to be heated in aqueous media, said aqueous media being maintained at temperatures of up to about 212° F., consisting of a continuous outer layer of polypropylene film and a continuous inner film layer of a high density ethylene-octene-1 copolymer, said copolymer comprising less than about 10% by weight of octene-1 and having a density of about 0.945 g/cc.
Claim 2
Dependent Claim
75 words
A two-layer coextruded, thermoplastic laminar bag construction particularly suitable for the containment of food which has to be heated in aqueous media, said aqueous media being maintained at temperatures of up to about 212° F., consisting of a continuous outer layer of polypropylene film and a continuous inner film layer of a high density ethylene-octene-1 copolymer, said copolymer comprising less than about 10% by weight of octene-1 and having a density of about 0.945 g/cc.
Claim 3
Dependent Claim
27 words
A plastic laminar bag construction in accordance with claim 1 wherein said polypropylene film layer has a thickness of from about 0.1 up to about 0.2 mil.
Claim 4
Dependent Claim
32 words
The thermoplastic bag of claim 1 wherein the high density polyethylene copolymer consists essentially of ethylene copolymerized with about 3% by weight of octene-1 and has a density of about 0.945 g/cc.
Claim 5
Dependent Claim
37 words
The bag of claim 3 wherein the bag construction consists essentially of said copolymer layer of about 0.5 to 3 mils thickness integrally adhered to a polypropylene layer of about 0.1-0.2 mils thickness and layers being coextruded.
Claim 6
Dependent Claim
17 words
The bag of claim 4 wherein the two-layer film has an overall thickness of about 1.2 mil.
References Cited (Backward Citations)
US3481804A
Cited
US3496061A
Cited
US3579416A
Cited
GB1440317A
Cited
US4147827A
Cited
US4211825A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-30 | 1985-06-01 | 1985-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-30 | 1989-06-01 | 1989-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-30 | 1993-06-01 | 1993-12-01 | $7700.00 | Window Closed / Lapsed |