US4399180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coextruded thermoplastic stretch-wrap
Assignee: Tyco Plastics Services AG
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Filing: 1982-04-29
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Granted: 1983-08-16
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Expires: 2002-04-29
Abstract
Abstract This present invention relates to novel coextruded thermoplastic film and the employment of such multi-layer film as stretch-wrap material for packaging of goods, including relatively large palletized loads of material. More specifically, such coextruded stretch-wrap films comprise three-layer laminations having a relatively thin skin layer and a relatively thicker core layer. Suitable skin layers include highly-branched low-density polyethylene, and suitable core layers include linear low-density polyethylene co-polymers, such as ethylene co-polymerized with a minor amount of at least one C4 to C10 alpha-olefin, such as octene-1 and 4-methyl-pentene-1, and butene-1.
Inventors
- 👤 William F. Briggs
- 👤 Edward M. Bullard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:16
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/32; Y; Y10; Y10S; Y10S428/00; Y10S428/911; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24992; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31938
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
58 words
A thermoplastic film adapted for use as a stretch film wrap comprising a coextruded three-layer thermoplastic film having a core layer comprising a linear low-density polyethylene, said linear low-density polyethylene consisting essentially of ethylene co-polymerized with a minor amount of at least one alpha-olefin having four to ten carbon atoms and exterior skin layers comprising highly-branched low-density polyethylene.
Claim 2
Dependent Claim
58 words
A thermoplastic film adapted for use as a stretch film wrap comprising a coextruded three-layer thermoplastic film having a core layer comprising a linear low-density polyethylene, said linear low-density polyethylene consisting essentially of ethylene co-polymerized with a minor amount of at least one alpha-olefin having four to ten carbon atoms and exterior skin layers comprising highly-branched low-density polyethylene.
Claim 3
Dependent Claim
41 words
A film according to claim 1 wherein said core layer consists essentially of linear low-density copolymer of ethylene with a minor amount of octene-1, having a density of about 0.916 to 0.925 and a melt index of about 1.0 to 6.0.
Claim 4
Dependent Claim
27 words
A film according to claim 1 wherein said linear low-density polyethylene contains about 1 to 10 weight % total of butene-1, 4-methyl pentene-1, octene-1 or mixtures thereof.
Claim 5
Dependent Claim
52 words
A film according to claim 1 wherein said core layer has a density of about 0.916 to about 0.925 and a melt index of about 1.0 to about 6.0 and said skin layers have a density of about 0.917 to about 0.922 and a melt index of about 4 to about 8.
References Cited (Backward Citations)
CA766727A
Cited
US3055784A
Cited
US2928756A
Cited
GB914411A
Cited
US3201302A
Cited
US3508944A
Cited
US3294577A
Cited
US3783089A
Cited
GB1368634A
Cited
US4022646A
Cited
US4050221A
Cited
US4008352A
Cited
US3936565A
Cited
GB1495380A
Cited
US4151318A
Cited
US4205021A
Cited
US4147827A
Cited
US4197150A
Cited
US4196240A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-15 | 1987-02-14 | 1987-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-15 | 1991-02-14 | 1991-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-15 | 1995-02-14 | 1995-08-16 | $7700.00 | Window Closed / Lapsed |