US5273797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Food package, retort lidding, and coextruded film therefor
Assignee: ExxonMobil Chemical Patents Inc
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Filing: 1990-01-16
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Granted: 1993-12-28
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Expires: 2010-01-16
Abstract
Abstract A seal layer for use in heat sealed containers, especially retortable polymer containers. A semirigid or rigid packaging container with a multilayer laminate heat sealed to a tray flange, the laminate having a barrier layer and the lidding being easily opened by cohesive failure of a layer containing as elastomer. The elastomer is preferably PIB in a heat seal film layer on a polypropylene tray.
Inventors
- 👤 Donald R. Hazelton
- 👤 Lawrence K. Locke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:53
CPC Classifications
B; B65; B65D; B65D81/00; B65D81/34; B32; B32B; B32B25/00; B32B25/04; B32B25/08; B32B27/00; B32B27/32; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/131; Y10T428/1317; Y10T428/1321; Y10T428/1328; Y10T428/1334; Y10T428/31504; Y10T428/31826; Y10T428/3183; Y10T428/31833; Y10T428/31837; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31917; Y10T428/31938
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
102 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising: a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and a minority of polyolefin, said polyolefin characterized as having a semi-crystalline or crystalline melting point of at least 110° C., and the elastomer present in said skin layer being selected from the group consisting of polyisobutylene, butyl rubber, halogenated butyl rubber, ethylene-propylene rubber, ethylene-propylenediene rubber, polyisoprene polychloroprene, styrene-butadiene rubber, polybutene copolymers, nitrile rubber and chlorosulfonated polyethylene.
Claim 2
Dependent Claim
102 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising: a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and a minority of polyolefin, said polyolefin characterized as having a semi-crystalline or crystalline melting point of at least 110° C., and the elastomer present in said skin layer being selected from the group consisting of polyisobutylene, butyl rubber, halogenated butyl rubber, ethylene-propylene rubber, ethylene-propylenediene rubber, polyisoprene polychloroprene, styrene-butadiene rubber, polybutene copolymers, nitrile rubber and chlorosulfonated polyethylene.
Claim 3
Dependent Claim
17 words
The multilayer film of claim 1 wherein said core layer comprises 55-70 weight percent of said elastomer.
Claim 4
Dependent Claim
30 words
The multilayer film of claim 1 further comprising a third, outer layer, said skin layer and said outer layer on opposite sides of said core layer and identical in composition.
Claim 5
Dependent Claim
16 words
The multilayer film of claim 1 wherein said polyolefin present in said skin layer is polypropylene.
Claim 6
Dependent Claim
11 words
The multilayer film of claim 4 wherein said elastomer is polyisobutylene.
Claim 7
Dependent Claim
12 words
The multilayer film of claim 4 wherein said elastomer is ethylene-propylenediene rubber.
Claim 8
Dependent Claim
68 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock, said multilayer heat seal film comprising: a skin layer comprised of a majority of polyolefin and of a minority of elastomer, and a core layer comprised of a majority of elastomer and of a minority of polyolefin, wherein said elastomer in said skin layer and said core layer is polyisobutylene.
Claim 9
Dependent Claim
68 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock, said multilayer heat seal film comprising: a skin layer comprised of a majority of polyolefin and of a minority of elastomer, and a core layer comprised of a majority of elastomer and of a minority of polyolefin, wherein said elastomer in said skin layer and said core layer is polyisobutylene.
Claim 10
Dependent Claim
20 words
The multilayer heat seal film of claim 7 wherein said polyolefin in said skin layer is a blend of polyolefins.
Claim 11
Dependent Claim
21 words
The multilayer heat seal film of claim 7 wherein said polyolefin in said core layer is a reactor copolymer of propylene.
Claim 12
Dependent Claim
23 words
The multilayer heat seal film of claim 7 wherein said polyolefin has a semi-crystalline or crystalline melting point of at least 110° C.
Claim 13
Dependent Claim
22 words
The multilayer heat seal film of claim 7 wherein said elastomer has a glass transition temperature (Tg) of less tan 0° C.
Claim 14
Dependent Claim
74 words
A lidding stock comprising an outer layer laminated to a barrier layer, said barrier layer laminated to a multilayer heat seal film, said multilayer heat seal film comprising, in combination: a skin layer comprised of a majority of polyolefin and of a minority of elastomer, and a core layer comprised of a majority of elastomer and of a minority of polyolefin, wherein said elastomer in said skin layer and said core layer is polyisobutylene.
Claim 15
Dependent Claim
74 words
A lidding stock comprising an outer layer laminated to a barrier layer, said barrier layer laminated to a multilayer heat seal film, said multilayer heat seal film comprising, in combination: a skin layer comprised of a majority of polyolefin and of a minority of elastomer, and a core layer comprised of a majority of elastomer and of a minority of polyolefin, wherein said elastomer in said skin layer and said core layer is polyisobutylene.
Claim 16
Dependent Claim
20 words
The multilayer heat seal film of claim 12 wherein said polyolefin in said skin layer is a blend of polyolefins.
Claim 17
Dependent Claim
21 words
The multilayer heat seal film of claim 12 wherein said polyolefin in said core layer is a reactor copolymer of propylene.
Claim 18
Dependent Claim
23 words
The multilayer heat seal film of claim 12 wherein said polyolefin has a semi-crystalline or crystalline melting point of at least 110° C.
Claim 19
Dependent Claim
22 words
The multilayer heat seal film of claim 12 wherein said elastomer has a glass transition temperature (Tg) of less than 0° C.
Claim 20
Dependent Claim
137 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising: a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and of a minority of polyolefin, said polyolefin characterized as having a semi-crystalline or crystalline melting point of at least 110° C. and the polyolefin present in said skin layer being selected from the group consisting of polypropylene, copolymers of ethylene and 3-15% of an olefin having 4 to 12 carbon atoms, polybutylene, and mixtures thereof and the elastomer present in said skin layer being selected from the group consisting of polyisobutylene, butyl rubber, halogenated butyl rubber, ethylene-propylene rubber, ethylene-propylenediene rubber, polyisoprene polychloroprene, styrene-butadiene rubber, polybutene copolymers, nitrile rubber and chlorosulfonated polyethylene.
Claim 21
Dependent Claim
137 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising: a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and of a minority of polyolefin, said polyolefin characterized as having a semi-crystalline or crystalline melting point of at least 110° C. and the polyolefin present in said skin layer being selected from the group consisting of polypropylene, copolymers of ethylene and 3-15% of an olefin having 4 to 12 carbon atoms, polybutylene, and mixtures thereof and the elastomer present in said skin layer being selected from the group consisting of polyisobutylene, butyl rubber, halogenated butyl rubber, ethylene-propylene rubber, ethylene-propylenediene rubber, polyisoprene polychloroprene, styrene-butadiene rubber, polybutene copolymers, nitrile rubber and chlorosulfonated polyethylene.
Claim 22
Dependent Claim
16 words
The multilayer film of claim 17 wherein said polyolefin present in said skin layer is polypropylene.
Claim 23
Dependent Claim
90 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising: a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and of a minority of polyolefin, wherein said elastomer in said skin layer and said core layer is polyisobutylene and wherein said polyolefin in said skin layer is a blend of polyolefins and said polyolefin in said core layer is a reactor copolymer of propylene.
Claim 24
Dependent Claim
90 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising: a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and of a minority of polyolefin, wherein said elastomer in said skin layer and said core layer is polyisobutylene and wherein said polyolefin in said skin layer is a blend of polyolefins and said polyolefin in said core layer is a reactor copolymer of propylene.
Claim 25
Dependent Claim
83 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising; a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and of a minority of polyolefin, said polyolefin characterized as having a semi-crystalline or crystalline melting point of at least 110° C. and said elastomer characterized as having a glass transition temperature (Tg) of less than 0° C.
Claim 26
Dependent Claim
83 words
A multilayer heat seal film having at least two layers for use in a multilayer laminate lidding stock comprising; a first skin layer comprised of a majority of polyolefin and a minority of elastomer; and a second, core layer comprised of a majority of elastomer and of a minority of polyolefin, said polyolefin characterized as having a semi-crystalline or crystalline melting point of at least 110° C. and said elastomer characterized as having a glass transition temperature (Tg) of less than 0° C.
References Cited (Backward Citations)
US4340641A
Cited
US4778697A
Cited
US4921749A
Cited
US4921749C1
Cited
US4784885A
Cited
US4769261A
Cited
US4937139A
Cited
US4929479A
Cited
US4879177A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-12-27 | 1997-06-28 | 1997-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-27 | 2001-06-28 | 2001-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-27 | 2005-06-28 | 2005-12-28 | $7700.00 | Window Closed / Lapsed |