EP0168928A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Wrapping film of ethylene copolymers
Assignee: Bcl Ltd
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Filing: 1985-05-21
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Granted: —
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Expires: 2005-05-21
Abstract
Abstract A wrapping film suitable for pallet stretch wrap applications is manufactured by the blown bubble process with extra cooling at the «frost line» from a blend of a linear ethylene/alpha olefin copolymer containing 3 to 18 % by weight of alpha olefin and from 10 to 75% or more preferably from 45 to 55% by weight of the blend of a linear ethylene/butene-1 copolymer containing 3 to 18 % by weight of butene-1. The alpha olefin is predominantly a C 6 to C 8 monomer or isomer thereof with or without a minor amount of a second different C 4 to C 8 olefin monomer, for example butene-1. Films of the blend have both high clarity and desirable tear resistance and break elongation properties. The films may contain a tackifying agent such as polyisobutylene.
Inventors
- 👤 Helen Ann Biddiscombe
- 👤 Christopher John Porter
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 17:29
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B29; B29C; B29C48/00; B29C48/03; B29C48/09; B29C48/10; B29C48/25; B29C48/88; B29C48/911; B29C48/9115; B29C48/912; B29C48/9135; B29C48/914; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0807; C08L23/0815; B29C48/001; B29C48/0018; B29C48/0019; B29C48/07; B29C48/08; C08J2323/00; C08J2323/02; C08J2323/18; C08L2205/00; C08L2205/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
140 words
A method of manufacturing a wrapping film suitable for use as a pallet stretch wrap comprising extruding through a ring die a blend of (1) a linear ethylene/alpha olefin copolymer containing from 3 to 18% by weight of alpha olefin based on the copolymer, the alpha olefin comprising at least a predominant amount of a monomer having from 6 to 8 carbon atoms, with (2) a linear ethylene/butene-1 copolymer containing from 3 to 18% by weight of butene-1 based on the butene-1 copolymer, the ethylene/butene-1 copolymer content in the blend being from 10 to 75% by weight of the blend, expanding the molten extrudate by air to form a bubble, cooling the travelling extrudate to a solid state to form a tubular film, directing further cooling means about the extrudate at the point of solidification and collapsing the tubular film.
Claim 2
Independent Claim
140 words
A method of manufacturing a wrapping film suitable for use as a pallet stretch wrap comprising extruding through a ring die a blend of (1) a linear ethylene/alpha olefin copolymer containing from 3 to 18% by weight of alpha olefin based on the copolymer, the alpha olefin comprising at least a predominant amount of a monomer having from 6 to 8 carbon atoms, with (2) a linear ethylene/butene-1 copolymer containing from 3 to 18% by weight of butene-1 based on the butene-1 copolymer, the ethylene/butene-1 copolymer content in the blend being from 10 to 75% by weight of the blend, expanding the molten extrudate by air to form a bubble, cooling the travelling extrudate to a solid state to form a tubular film, directing further cooling means about the extrudate at the point of solidification and collapsing the tubular film.
Claim 3
Dependent Claim
26 words
A method as claimed in claim 1 in which the ethylene/butene-1 copolymer content in the blend is from 45 to 55% by weight of the blend.
Claim 4
Dependent Claim
27 words
A method as claimed in claim 1 or claim 2 in which the ethylene/alpha olefin copolymer is a copolymer of ethylene with hexene or heptene or octene.
Claim 5
Dependent Claim
42 words
A method as claimed in claim 3 in which the alpha olefin includes a minor amount with respect to the monomer having from 6 to 8 carbon atoms of a second different alpha olefin monomer having from 4 to 8 carbon atoms.
Claim 6
Dependent Claim
17 words
A method as claimed in claim 4 in which the second different alpha olefin monomer is butene-1.
Claim 7
Dependent Claim
22 words
A method as claimed in claim 1 or claim 2 in which the linear ethylene/alpha olefin copolymer is a linear ethylene/octene-1 copolymer.
Claim 8
Independent Claim
31 words
A method as claimed in any one of the preceding claims in which the further cooling means is a jet of cold air directed from an annulus arranged around the bubble.
Claim 9
Independent Claim
35 words
A method as claimed in any one of the preceding claims in which the blend further contains a tackifying agent comprising from 0.5 to 4.0% by weight of the blend of polyisobutylene or atactic polypropylene.
Claim 10
Dependent Claim
30 words
A method for securing to a pallet a load of goods which comprises wrapping around said pallet and said goods positioned thereon a wrapping film as claimed in claim 1.
Claim 11
Dependent Claim
14 words
A pallet whenever wrapped in accordance with a method as claimed in claim 9.
References Cited (Backward Citations)
No citation records indexed.
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