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US4196240A Expired / Lapsed US ⏱️ 0.0 years remaining

Heat shrinkable multilayer packaging film of blended copolymers and elastomers

Assignee: Union Carbide Corp
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Filing: 1978-01-18
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Granted: 1980-04-01
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Expires: 1998-01-18
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Abstract

Abstract A heat-shrinkable multilayer film suitable for use in the packaging of a frozen poultry, includes a first outer layer comprising a blend of propylene-ethylene copolymer having a high isotactic molecular structure with less than about 6% by weight being ethylene and having a melt flow of from about 1.5 to about 18 decigrams per minute; a (butene-1)-ethylene copolymer having a high isotactic molecular structure with less than about 10% by weight ethylene and having a melt flow of from about 0.1 to about 5.0 decigrams per minute, and a thermoplastic elastomer selected from the group consisting of ethylene-propylene copolymers and ethylene-propylene diene terpolymers, the ratio by weight of the propylene-ethylene copolymer to the (butene-1)-ethylene copolymer being from about 2:1 to about 1:2 and the thermoplastic elastomer being present from about 10% to about 50% by weight, and a second outer layer comprising an ethylene-(butene-1) copolymer having a melt flow of from about 0.1 to about 1.0 decigram per minute, having a density of from about 0.916 to about 0.920 gram per cubic centimeter, and being a linear polymer; the multilayer film being biaxially oriented.

Inventors

  • 👤 Stanley Lustig
  • 👤 Stephen J. Vicik
  • 👤 William J. Kohler

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 15:14
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/32; B32B7/00; B32B7/04; B32B7/12; B32B2250/00; B32B2250/24; B32B2250/242; B32B2270/00; B32B2307/00; B32B2307/50; B32B2307/514; B32B2307/518; B32B2307/70; B32B2307/732; B32B2307/734; B32B2307/736; B32B2323/00; B32B2439/00; B32B2439/40; B32B2439/46; B32B2439/70; Y; Y10; Y10S; Y10S206/00; Y10S206/819; Y10S383/00; Y10S383/908; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/13; Y10T428/1328; Y10T428/24; Y10T428/24942; Y10T428/24992; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31928

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 180 words
A heat-shrinkable multilayer film adapted for packaging of frozen poultry, comprising: a first outer layer comprising a blend of a propylene-ethylene copolymer having a high isotactic molecular structure, containing up to about 6% by weight ethylene, and having a melt flow of from about 1.5 to about 18 decigrams per minute; a (butene-1)-ethylene copolymer having a high isotactic molecular structure, containing from about 1% to about 10% by weight ethylene, and having a melt flow of from about 0.1 to about 5.0 decigrams per minute; and a thermoplastic elastomer selected from the group consisting of ethylene-propylene copolymers and ethylene propylene diene terpolymers, the ratio by weight of said propylene-ethylene copolymer to said (butene-1)-ethylene copolymer being from about 2:1 to about 1:2 and said thermoplastic elastomer being present from about 10% by weight to about 50% by weight; and a second outer layer comprising an ethylene-(butene-1) copolymer having a melt flow of from about 0.1 to about 1.0 decigram per minute and having a density of from about 0.916 to about 0.920 gram per cubic centimeter; said film being biaxially oriented.
Claim 2
Dependent Claim 180 words
A heat-shrinkable multilayer film adapted for packaging of frozen poultry, comprising: a first outer layer comprising a blend of a propylene-ethylene copolymer having a high isotactic molecular structure, containing up to about 6% by weight ethylene, and having a melt flow of from about 1.5 to about 18 decigrams per minute; a (butene-1)-ethylene copolymer having a high isotactic molecular structure, containing from about 1% to about 10% by weight ethylene, and having a melt flow of from about 0.1 to about 5.0 decigrams per minute; and a thermoplastic elastomer selected from the group consisting of ethylene-propylene copolymers and ethylene propylene diene terpolymers, the ratio by weight of said propylene-ethylene copolymer to said (butene-1)-ethylene copolymer being from about 2:1 to about 1:2 and said thermoplastic elastomer being present from about 10% by weight to about 50% by weight; and a second outer layer comprising an ethylene-(butene-1) copolymer having a melt flow of from about 0.1 to about 1.0 decigram per minute and having a density of from about 0.916 to about 0.920 gram per cubic centimeter; said film being biaxially oriented.
Claim 3
Dependent Claim 21 words
The film of claim 1, wherein the ratio by weight of said propylene-ethylene copolymer to said (butene-1)-ethylene copolymer is about 2:1.
Claim 4
Dependent Claim 21 words
The film of claim 1, wherein the ratio by weight of said propylene-ethylene copolymer to said (butene-1)-ethylene copolymer is about 1:1.
Claim 5
Dependent Claim 21 words
The film of claim 1, wherein the ratio by weight of said propylene-ethylene copolymer to said (butene-1)-ethylene copolymer is about 1:2.
Claim 6
Dependent Claim 23 words
The film of claim 1, wherein said propylene-ethylene copolymer has a density of from about 0.89 to about 0.91 gram per cubic centimeter.
Claim 7
Dependent Claim 23 words
The film of claim 1, wherein said propylene-ethylene copolymer has a melt flow of from about 3.5 to about 12.0 decigrams per minute.
Claim 8
Dependent Claim 19 words
The film of claim 1, wherein said thermoplastic elastomer is present from about 20% to about 40% by weight.
Claim 9
Dependent Claim 14 words
The film of claim 1, wherein said thermoplastic elastomer comprises an ethylene-propylene copolymer elastomer.
Claim 10
Dependent Claim 21 words
The film of claim 8, wherein said ethylene-propylene copolymer elastomer comprises ethylene in the amount of at least 50% by weight.
Claim 11
Dependent Claim 20 words
The film of claim 9, wherein said ethylene-propylene copolymer elastomer comprises ethylene in the amount of about 70% by weight.
Claim 12
Dependent Claim 25 words
The film of claim 10, wherein said ethylene-propylene copolymer elastomer has a Mooney viscosity at 260° F. of from about 23 to about 50 centipoises.
Claim 13
Dependent Claim 15 words
The film of claim 1, wherein said thermoplastic elastomer comprises an ethylene-propylene diene modified terpolymer.
Claim 14
Dependent Claim 35 words
The film of claim 1, wherein the ratio by weight of said propylene-ethylene copolymer to said (butene-1)-ethylene copolymer is about 1:1 and said thermoplastic elastomer is present from about 20% to about 40% by weight.
Claim 15
Dependent Claim 22 words
The film of claim 1, further comprising a core layer comprising an extrudable adhesive capable of being biaxially oriented and heat shrinkable.
Claim 16
Dependent Claim 49 words
The film of claim 14, wherein said adhesive is selected from the group consisting of ionomers and ethylene vinyl acetates having a melt flow of from about 0.1 to about 1.0 decigrams per minute and having a vinyl acetate content of from about 9% to about 12% by weight.
Claim 17
Dependent Claim 23 words
The film of claim 1, wherein said ethylene(butene-1) copolymer has a melt flow of from about 0.3 to about 0.8 decigrams per minute.
Claim 18
Dependent Claim 21 words
The film of claim 1, wherein said ethylene(butene-1) copolymer has a flow rate ratio of from about 45 to about 100.
Claim 19
Dependent Claim 23 words
The film of claim 1, wherein said ethylene(butene-1) copolymer has a density of from about 0.918 to about 0.920 gram per cubic centimer.
Claim 20
Dependent Claim 13 words
The film of claim 1, wherein said ethylene(butene-1) copolymer is a linear polymer.
Claim 21
Dependent Claim 9 words
A bag fabricated from the film of claim 1.
Claim 22
Dependent Claim 20 words
The film as claimed in claim 14 consisting essentially of said first and second outer layers and said core layer.
Claim 23
Dependent Claim 25 words
The film of claim 21, wherein said first outer layer consists essentially of said blend and said outer layer consists essentially of said ethylene-(butene-1) copolymer.

References Cited (Backward Citations)

US3634553A Cited
US3634552A Cited
US3900635A Cited
GB1508033A Cited
US4082877A Cited
US4078020A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-04-01 1983-10-01 1984-04-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-04-01 1987-10-01 1988-04-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-04-01 1991-10-01 1992-04-01 $7700.00 Window Closed / Lapsed

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