Patent US1961856A successfully refreshed from Google Patents.
Patent US5032434A successfully refreshed from Google Patents.
US5032434A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compatibilized blend comprising skin polymer, ethylene-vinyl alcohol copolymer, and poly-2-oxazoline
Assignee: Alcoa Corp
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Filing: 1989-04-07
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Granted: 1991-07-16
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Expires: 2009-04-07
Abstract
Abstract A polymer blend comprises a skin polymer, an ethylene-vinyl alcohol copolymer and a poly-2-oxazoline. The polymer blend possesses good gas barrier properties and excellent mechanical strength. A particularly preferred blend comprises an improved reclaim layer of a six-layer composite sheet suitable for thermoforming into a food package.
Inventors
- 👤 Isaac C. Sanchez
- 👤 Willy M. Balaba
- 👤 Lucy T. Stevenson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:29
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/32; B32B27/06; B32B27/08; B32B27/30; B32B27/306; B32B2250/00; B32B2250/03; B32B2250/24; B32B2250/40; B32B2307/00; B32B2307/70; B32B2307/724; B32B2307/7242; B32B2323/00; B32B2323/10; B32B2329/00; B32B2439/00; B32B2439/70; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1334; Y10T428/1341; Y10T428/1352; Y10T428/1379; Y10T428/1383; Y10T428/31504; Y10T428/31507; Y10T428/31786; Y10T428/31797; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
72 words
A multilayer sheet material suitable for forming into a container, said sheet material consisting essentially of: (a) first and second skin layers each comprising a polypropylene homopolymer or copolymer skin polymer; and (b) an intermediate layer between said first and second skin layers and comprising: (1) about 10-90 wt% of a polypropylene homopolymer or copolymer; (2) about 5-60 wt% of an ethylene-vinyl alcohol copolymer; and (3) about 5-50 wt% of poly-2-ethyl oxazoline.
Claim 2
Dependent Claim
72 words
A multilayer sheet material suitable for forming into a container, said sheet material consisting essentially of: (a) first and second skin layers each comprising a polypropylene homopolymer or copolymer skin polymer; and (b) an intermediate layer between said first and second skin layers and comprising: (1) about 10-90 wt% of a polypropylene homopolymer or copolymer; (2) about 5-60 wt% of an ethylene-vinyl alcohol copolymer; and (3) about 5-50 wt% of poly-2-ethyl oxazoline.
Claim 3
Dependent Claim
15 words
The multilayer sheet material of claim 1 wherein said skin polymer comprises a polypropylene homopolymer.
Claim 4
Dependent Claim
29 words
The multilayer sheet material of claim 1 wherein said intermediate layer comprises about 50-90 wt% polypropylene homopolymer, about 5-25 wt% ethylene-vinyl alcohol copolymer, and about 5-25 wt% poly-2-ethyl oxazoline.
Claim 5
Dependent Claim
12 words
A food container formed from the multilayer sheet material of claim 3.
Claim 6
Dependent Claim
29 words
The multilayer sheet material of claim 1 wherein said intermediate layer comprises about 60-80 wt% polypropylene homopolymer, about 10-20 wt% ethylene-vinyl alcohol copolymer, and about 5-25 wt% poly-2-ethyl oxazoline.
Claim 7
Dependent Claim
12 words
A food container formed from the multilayer sheet material of claim 1.
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) | 1994-07-15 | 1995-01-14 | 1995-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-15 | 1999-01-14 | 1999-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-15 | 2003-01-14 | 2003-07-16 | $7700.00 | Window Closed / Lapsed |