US4892603A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Irradiated multilayer film for primal meat packaging
Assignee: Viskase Corp
•
Filing: 1988-09-09
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Granted: 1990-01-09
•
Expires: 2008-09-09
Abstract
Abstract A heat-shrinkable, multilayer film suitable for use in fabricating bags for packaging primal and sub-primal meat cuts and processed meats. The multilayer film has a first outer layer of an ethylene-vinyl acetate copolymer, a core layer of a barrier film comprising vinylidene chloride-methyl acrylate copolymer, and a second outer layer of an ethylene-vinyl acetate copolymer. The multilayer film is preferably made by co-extrusion of the layers, and then it is biaxially stretched. After biaxial stretching, the multilayer film is irradiated to a dosage level of between 1 megarad and 5 megarads and heat-sealed in the form of a bag. The bag has improved storage stability characteristics.
Inventors
- 👤 Stanley Lustig
- 👤 Jeffrey M. Schuetz
- 👤 Stephen J. Vicik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:23
CPC Classifications
B; B65; B65D; B65D31/00; B65D31/02; B32; B32B; B32B27/00; B32B27/16
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
67 words
A process for producing a multilayer film suitable for packaging primal and sub-primal meat cuts and processed meats comprising: (a) co-extruding a first outer film layer, a core film layer comprising a vinylidene chloride-methyl acrylate copolymer, and a second outer film layer; (b) biaxially stretching said multilayer film; and (c) irradiating said multilayer film to a dosage level of between about 1 megarad and about 5 megarads.
Claim 2
Dependent Claim
67 words
A process for producing a multilayer film suitable for packaging primal and sub-primal meat cuts and processed meats comprising: (a) co-extruding a first outer film layer, a core film layer comprising a vinylidene chloride-methyl acrylate copolymer, and a second outer film layer; (b) biaxially stretching said multilayer film; and (c) irradiating said multilayer film to a dosage level of between about 1 megarad and about 5 megarads.
Claim 3
Dependent Claim
77 words
A process for producing a multilayer film suitable for packaging primal and sub-primal meat cuts and processed meats comprising: (a) co-extruding a first outer film layer comprising an ethylene-vinyl acetate copolymer, a core film layer comprising a vinylidene chloride-methyl acrylate copolymer, and a second outer film layer comprising an ethylene-vinyl acetate copolymer; (b) biaxially stretching said multilayer film; and (c) irradiating said multilayer film to a dosage level of between about 1 megarad and about 5 megarads.
Claim 4
Dependent Claim
77 words
A process for producing a multilayer film suitable for packaging primal and sub-primal meat cuts and processed meats comprising: (a) co-extruding a first outer film layer comprising an ethylene-vinyl acetate copolymer, a core film layer comprising a vinylidene chloride-methyl acrylate copolymer, and a second outer film layer comprising an ethylene-vinyl acetate copolymer; (b) biaxially stretching said multilayer film; and (c) irradiating said multilayer film to a dosage level of between about 1 megarad and about 5 megarads.
Claim 5
Dependent Claim
54 words
A process in accordance with claim 2 wherein said first outer layer comprises an ethylene-vinyl acetate copolymer having a melt index of from about 0.1 to about 1.0 decigram per minute, and a vinyl acetate content of from about 9 to about 15 weight percent, based on the weight of said ethylene-vinyl acetate copolymer.
Claim 6
Dependent Claim
55 words
A process in accordance with claim 2 wherein said first outer film layer comprises an ethylene-vinyl acetate copolymer having a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 9 to about 15 weight percent, based on the weight of said ethylene-vinyl acetate copolymer.
Claim 7
Dependent Claim
54 words
A process in accordance with claim 2 wherein said second outer layer comprises an ethylene-vinyl acetate copolymer having a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 3 to about 18 weight percent, based on the weight of said ethylene-vinyl acetate copolymer.
Claim 8
Dependent Claim
36 words
A process in accordance with claim 2 wherein said core layer comprises a vinylidene chloride-methyl acrylate copolymer containing at least about 85 weight percent of vinylidene chloride, based on the weight of said vinylidene chloride copolymer.
Claim 9
Dependent Claim
33 words
A process in accordance with claim 2 wherein said vinylidene chloride copolymer contains a maximum of 5 weight percent plasticizer, based on the total blend weight of additives and said vinylidene chloride copolymer.
Claim 10
Dependent Claim
38 words
A process in accordance with claim 2 wherein said core layer comprises a vinylidene chloride-methyl acrylate copolymer containing from about 5 to about 15 weight percent of methyl acrylate, based on the weight of said vinylidene chloride copolymer.
Claim 11
Dependent Claim
106 words
A process in accordance with claim 2 wherein said second outer layer comprises a blend of at least two ethylene-vinyl acetate copolymers, wherein one of said ethylene-vinyl acetate copolymers has a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 10 to about 18 weight percent, based on the weight of said copolymer, and one of said ethylene-vinyl acetate copolymers has a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 2 to about 10 weight percent, based on the weight of said copolymer.
Claim 12
Dependent Claim
40 words
A process in accordance with claim 9 wherein said blend of said ethylene-vinyl acetate copolymers has a vinyl acetate content of from about 3 to about 18 weight percent, based on the weight of said blend of ethylene-vinyl acetate copolymers.
Claim 13
Dependent Claim
23 words
A process in accordance with claim 2 wherein said first outer layer has a thickness from about 1.1 mils to about 1.6 mils.
Claim 14
Dependent Claim
23 words
A process in accordance with claim 2 wherein said core layer has a thickness of from about 0.25 mil to about 0.45 mil.
Claim 15
Dependent Claim
24 words
A process in accordance with claim 2 wherein said second outer layer has a thickness of from about 0.4 mil to about 1.0 mil.
Claim 16
Dependent Claim
24 words
A process in accordance with claim 2 wherein said multilayer film has a total thickness of from about 1.75 mils to about 3.0 mils.
Claim 17
Dependent Claim
26 words
A process in accordance with claim 2 wherein said multilayer film is irradiated to a dosage level of between about 2 megarads and about 3 megarads.
Claim 18
Dependent Claim
18 words
A process in accordance with claim 2 including fabricating said multilayer film into the form of a bag.
Claim 19
Dependent Claim
291 words
A process for producing a multilayer film suitable for packaging primal and sub-primal meat cuts and processed meats comprising: (a) co-extruding a first outer film layer comprising an ethylene-vinyl acetate copolymer having a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 9 to about 15 weight percent, based on the weight of said ethylene-vinyl acetate copolymer, said ethylene-vinyl acetate copolymer being selected from group consisting of (a) a single ethylene-vinyl acetate copolymer, and (b) a blend of ethylene-vinyl acetate copolymers having melt indices and vinyl acetate contents within the aforementioned ranges; a core film layer comprising a vinylidene chloridemethyl acrylate copolymer; and a second outer film layer comprising an ethylene-vinyl acetate copolymer selected from the group consisting of (a) an ethylene-vinyl acetate copolymer having a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 3 to about 18 weight percent, based on the weight of said ethylene-vinyl acetate copolymer, and (b) a blend of at least two ethylene-vinyl acetate copolymers, wherein one of said ethylene-vinyl acetate copolymers has a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 10 to about 18 weight percent, based on the weight of said copolymer, and the other ethylene-vinyl acetate copolymer has a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 2 to about 10 weight percent, based on the weight of said copolymer; (b) biaxially stretching said multilayer film; and (c) irradiating said multilayer film to a dosage level of between about 1 megarad and about 5 megarads.
Claim 20
Dependent Claim
291 words
A process for producing a multilayer film suitable for packaging primal and sub-primal meat cuts and processed meats comprising: (a) co-extruding a first outer film layer comprising an ethylene-vinyl acetate copolymer having a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 9 to about 15 weight percent, based on the weight of said ethylene-vinyl acetate copolymer, said ethylene-vinyl acetate copolymer being selected from group consisting of (a) a single ethylene-vinyl acetate copolymer, and (b) a blend of ethylene-vinyl acetate copolymers having melt indices and vinyl acetate contents within the aforementioned ranges; a core film layer comprising a vinylidene chloridemethyl acrylate copolymer; and a second outer film layer comprising an ethylene-vinyl acetate copolymer selected from the group consisting of (a) an ethylene-vinyl acetate copolymer having a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 3 to about 18 weight percent, based on the weight of said ethylene-vinyl acetate copolymer, and (b) a blend of at least two ethylene-vinyl acetate copolymers, wherein one of said ethylene-vinyl acetate copolymers has a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 10 to about 18 weight percent, based on the weight of said copolymer, and the other ethylene-vinyl acetate copolymer has a melt index of from about 0.1 to about 1.0 decigram per minute and a vinyl acetate content of from about 2 to about 10 weight percent, based on the weight of said copolymer; (b) biaxially stretching said multilayer film; and (c) irradiating said multilayer film to a dosage level of between about 1 megarad and about 5 megarads.
Claim 21
Dependent Claim
29 words
A process in accordance with claim 17 wherein said vinylidene chloride-methyl acrylate copolymer contains at least about 85 weight percent vinylidene chloride, based on the weight of said copolymer.
Claim 22
Dependent Claim
34 words
A process in accordance with claim 17 wherein said vinylidene chloride-methyl acrylate copolymer contains a maximum of 5 weight percent plasticizer, based on the total blend weight of additives and said vinylidene chloride copolymer.
Claim 23
Dependent Claim
33 words
A process in accordance with claim 17 wherein said vinylidene chloride copolymer contains from about 5 to about 15 weight percent of methyl acrylate, based on the weight of said vinylidene chloride copolymer.
Claim 24
Dependent Claim
23 words
A process in accordance with claim 17 wherein said first outer layer has a thickness from about 1.1 mils to about 1.6 mils.
Claim 25
Dependent Claim
23 words
A process in accordance with claim 17 wherein said core layer has a thickness of from about 0.25 mil to about 0.45 mil.
Claim 26
Dependent Claim
24 words
A process in accordance with claim 17 wherein said second outer layer has a thickness of from about 0.4 mil to about 1.0 mil.
Claim 27
Dependent Claim
24 words
A process in accordance with claim 17 wherein said multilayer film has a total thickness of from about 1.75 mils to about 3.0 mils.
Claim 28
Dependent Claim
26 words
A process in accordance with claim 17 wherein said multilayer film is irradiated to a dosage level of between about 2 megarads and about 3 megarads.
Claim 29
Dependent Claim
18 words
A process in accordance with claim 17 including fabricating said multilayer film into the form of a bag.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-08 | 1993-07-10 | 1994-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-08 | 1997-07-10 | 1998-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-08 | 2001-07-10 | 2002-01-09 | $7700.00 | Window Closed / Lapsed |