EP0597502A2
Expired / Lapsed
EP
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Heat shrinkable films containing single site catalyzed copolymers
Assignee: Cryovac LLC
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Filing: 1993-11-12
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Granted: —
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Expires: 2013-11-12
Abstract
Abstract The present invention is directed to a heat-shrinkable, thermoplastic film or bag which contains at least one homogeneous ethylene alpha-olefin copolymer having a density of at least 0.90 g/cc. Oriented films made in accordance with the present invention exhibit improved optics and improved impact resistance. A homogeneous ethylene alpha-olefin may be present in a monolayer film either alone or in a blend or may be included in one or more layers of a multilayer film in accordance with the present invention.
Inventors
- 👤 Robert Babrowicz
- 👤 Blaine C. Childress
- 👤 Kelly R. Ahlgren
- 👤 Gautem P. Shah
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 08:28
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/32; B32B27/06; B32B27/08; B32B27/30; B32B27/304; B32B27/306; B32B27/308; B32B27/34; C; C08; C08J; C08J5/00; C08J5/18; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0807; C08L23/0815; B32B2307/00; B32B2307/30; B32B2307/31; B32B2307/70; B32B2307/72; B32B2307/732; B32B2307/734; B32B2307/736; C08J2323/00; C08J2323/02; C08J2323/04; C08J2323/08; C08L2205/00; C08L2205/02; C08L2205/03; C08L2314/00; C08L2314/06; Y; Y10; Y10S; Y10S526/00; Y10S526/943; Y10T; Y10T428/00; Y10T428/13; Y10T428/1328; Y10T428/1334; Y10T428/1341; Y10T428/26; Y10T428/266; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31928; Y10T428/31938
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
34 words
A heat shrinkable film comprising a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin having from three to ten carbon atoms, said copolymer having a density of at least about 0.90 g/cc.
Claim 2
Dependent Claim
24 words
A heat shrinkable film as set forth in claim 1, wherein said single site catalyzed copolymer is blended with another thermoplastic homopolymer or copolymer.
Claim 3
Dependent Claim
33 words
A heat shrinkable film as set forth in claim 2, wherein said other thermoplastic homopolymer or copolymer is a heterogeneous polymer of ethylene and an alpha-olefin having from three to ten carbon atoms.
Claim 4
Dependent Claim
21 words
A heat shrinkable film as set forth in claim 3 wherein said heterogeneous copolymer has a density below about 0.90 g/cc.
Claim 5
Dependent Claim
21 words
A heat shrinkable film as set forth in claim 3 wherein said heterogeneous copolymer has a density above about 0.90 g/cc.
Claim 6
Dependent Claim
51 words
A heat shrinkable film as set forth in claim 2, wherein said other thermoplastic homopolymer or copolymer is a copolymer of ethylene and a second comonomer selected from the group consisting of vinyl acetate, alkyl acrylate, carbon monoxide, butadiene, styrene, acrylic acid, and a metal neutralized salt of an acrylic acid.
Claim 7
Dependent Claim
22 words
A heat shrinkable film as set forth in claim 2, wherein said thermoplastic homopolymer or copolymer is a homopolymer of an alpha-olefin.
Claim 8
Dependent Claim
29 words
A heat shrinkable film as set forth in claim 1, wherein said other copolymer is a copolymer of ethylene and an alpha-olefin having from three to eight carbon atoms.
Claim 9
Dependent Claim
36 words
A heat shrinkable thermoplastic film as set forth in claim 8 wherein said homogeneous copolymer is a copolymer of ethylene and butene, or a copolymer of ethylene and hexene, or a copolymer of ethylene and octene.
Claim 10
Dependent Claim
34 words
A heat shrinkable film as set forth in claims 1 to 9, wherein said film is a multilayer film and said homogeneous copolymer is present in at least one layer of said multilayer film.
Claim 11
Dependent Claim
20 words
A heat shrinkable film as set forth in claim 10, wherein said homogeneous copolymer is present in an outer layer.
Claim 12
Dependent Claim
19 words
A heat shrinkable film as set forth in claim 11, wherein said outer layer is a heat sealing layer.
Claim 13
Dependent Claim
20 words
A heat shrinkable film as set forth in claim 10, wherein said homogeneous copolymer is present in an inner layer.
Claim 14
Dependent Claim
41 words
A heat shrinkable film having a substantially symmetrical structure comprising: outer layers comprising a propylene homopolymer or copolymer; and a core layer comprising a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin having from four to eight carbon atoms.
Claim 15
Dependent Claim
45 words
A heat shrinkable film as set forth in claim 14, wherein said propylene homopolymer or copolymer is a copolymer of from about 100 % to about 90 % by weight of propylene and from about 0 % to about 10 % by weight of ethylene.
Claim 16
Dependent Claim
47 words
A heat shrinkable multilayer film comprising: a heat sealing layer; an inner layer comprising a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin having from three to eight carbon atoms, said copolymer having a density of at least about 0.90 g/cc; and a barrier layer.
Claim 17
Dependent Claim
80 words
A heat shrinkable multilayer film as set forth in claim 16, wherein said heat sealing layer comprises a copolymer of ethylene and a comonomer selected from the group consisting of vinyl acetate, alkyl acrylate, acrylic acid, and a metal neutralized salt of an acrylic acid, or a heterogeneous copolymer of ethylene and an alpha-olefin having from three to ten carbon atoms, or a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin having from three to ten carbon atoms.
Claim 18
Dependent Claim
44 words
A heat shrinkable multilayer film comprising: a heat sealing layer comprising a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin having from three to eight carbon atoms, said copolymer having a density of at least about 0.90 g/cc; and a barrier layer.
Claim 19
Dependent Claim
43 words
A heat shrinkable multilayer film as set forth in claims 16 or 18, wherein said barrier layer comprises a copolymer of vinylidene chloride and methyl acrylate, or a copolymer of vinylidene chloride and vinyl chloride, or an ethylene vinyl alcohol, or a nylon.
Claim 20
Dependent Claim
18 words
A heat shrinkable multilayer film as set forth in claims 16 to 19, including an outer abuse layer.
Claim 21
Dependent Claim
21 words
A heat shrinkable multilayer film as set forth in claims 16 to 20, further including at least one inner adhesive layer.
Claim 22
Dependent Claim
62 words
A heat shrinkable film comprising at least two layers wherein at least one of said layers comprises a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin copolymer of ethylene and an alpha-olefin having from three to eight carbon atoms, said copolymer having a density of at least about 0.90 g/cc and wherein at least one of said layers is crosslinked.
Claim 23
Dependent Claim
48 words
A heat shrinkable multilayer film having a substantially symmetrical structure comprising: outer layers comprising a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin having from three to eight carbon atoms, said copolymer having a density of at least about 0.90 g/cc; and an inner core layer.
Claim 24
Dependent Claim
46 words
A heat shrinkable multilayer film as set forth in claim 23, wherein said inner core layer comprises a copolymer of ethylene and a second comonomer selected from the group consisting of vinyl acetate, alkyl acrylate, acrylic acid, and a metal neutralized salt of an acrylic acid.
Claim 25
Dependent Claim
29 words
A heat shrinkable multilayer film as set forth in claim 23 and 24 further including two substantially identical inner layers immediately adjacent opposed surfaces of said inner core layer.
Claim 26
Dependent Claim
50 words
A heat shrinkable multilayer film as set forth in claim 25, wherein said inner layers comprise a heterogeneous copolymer of ethylene and an alpha-olefin having from three to ten carbon atoms, or a homogeneous single site catalyzed copolymer of ethylene and an alpha-olefin having from three to eight carbon atoms.
Claim 27
Dependent Claim
36 words
A heat shrinkable multilayer film as set forth in claims 23 to 26, wherein said outer layers further include at least one heterogeneous copolymer of ethylene and an alpha-olefin having from three to ten carbon atoms.
References Cited (Backward Citations)
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