EP0008904A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Heat sealable polypropylene film and method for its production
Assignee: Bcl Ltd
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Filing: 1979-08-20
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Granted: —
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Expires: 1999-08-20
Abstract
Abstract A heat-sealable oriented polypropylene film comprising a base oriented polypropylene film having on one surface a layer of a random propylene/ethylene copolymer (ethylene content 2-6% by weight) and on the other surface a predominantly linear random copolymer of ethylene and a further alpha olefin having at least three carbon atoms per molecule (for example propylene and butene-1) the further alpha olefin content being 6-40% by weight. The film is particularly useful for packaging merchandise on horizontal form-fill-seal packaging machines.
Inventors
- 👤 Herbert James Ward
- 👤 Derek James Dobbie
- 👤 Brian Lyall
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 13:01
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/32; B32B27/06; B32B27/08; B32B27/322; C; C08; C08J; C08J7/00; C08J7/04; C08J7/0427; C09; C09J; C09J123/00; C09J123/02; C09J123/16; B32B2250/00; B32B2250/24; B32B2250/242; B32B2272/00; B32B2307/00; B32B2307/30; B32B2307/31; B32B2307/50; B32B2307/514; B32B2439/00; B32B2439/40; C08J2323/00; C08J2323/02; C08J2323/10; C08J2323/12; C08J2423/00; C08L; C08L2666/00; C08L2666/02; C08L2666/04; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31938
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
77 words
A heat-sealable oriented polypropylene film comprising a base film of oriented polypropylene having on one surface a layer of a random propylene/ ethylene copolymer in which the ethylene content lies in the range between 2% and 6% by weight and on the other surface a predominantly linear random copolymer of ethylene and between 6% and 40% by weight of the random copolymer of at least one further alpha olefin having at least three carbon atoms per molecule.
Claim 2
Dependent Claim
77 words
A heat-sealable oriented polypropylene film comprising a base film of oriented polypropylene having on one surface a layer of a random propylene/ ethylene copolymer in which the ethylene content lies in the range between 2% and 6% by weight and on the other surface a predominantly linear random copolymer of ethylene and between 6% and 40% by weight of the random copolymer of at least one further alpha olefin having at least three carbon atoms per molecule.
Claim 3
Dependent Claim
32 words
A polypropylene film as claimed in claim 1 in which amount of the further alpha olefin in the predominantly linear random copolymer lies in the range between 10% and 35% by weight.
Claim 4
Dependent Claim
19 words
A polypropylene film as claimed in claim 1 or claim 2 in which the further alpha olefin is propylene.
Claim 5
Dependent Claim
19 words
A polypropylene film as claimed in claim 1 or claim 2 in which the further alpha olefin is butene-1.
Claim 6
Dependent Claim
14 words
A polypropylene film as claimed in claim 1 substantially as described in the Example.
Claim 7
Independent Claim
96 words
A method for the manufacture of a heat-sealable oriented polypropylene film comprising applying to one surface of a base polypropylene film a layer of a random propylene/ethylene copolymer in which the ethylene content lies in the range between 2% and 6% by weight and to the other surface a predominantly linear random copolymer of ethylene and between 6% and 40% by weight of the random copolymer of at least one further alpha olefin having at least three carbon atoms per molecule, bringing the combination to a stretch orientatable condition and stretching in at least one direction.
Claim 8
Independent Claim
96 words
A method for the manufacture of a heat-sealable oriented polypropylene film comprising applying to one surface of a base polypropylene film a layer of a random propylene/ethylene copolymer in which the ethylene content lies in the range between 2% and 6% by weight and to the other surface a predominantly linear random copolymer of ethylene and between 6% and 40% by weight of the random copolymer of at least one further alpha olefin having at least three carbon atoms per molecule, bringing the combination to a stretch orientatable condition and stretching in at least one direction.
Claim 9
Dependent Claim
65 words
A method as claimed in claim 6 in which the layer of the propylene/ethylene copolymer and the layer of the copolymer of ethylene and at least one further alpha olefin are supplied to the base polypropylene film during co-extrusion of a melt of the copolymers and the polypropylene through a slot or annular orifice die following by quenching prior to stretching under stretch orientatable conditions.
Claim 10
Dependent Claim
37 words
A method as claimed in claim 6 or claim 7 in which the amount of the further alpha olefin in the predominantly linear copolymer lies in the range between 10% and 35% by weight of the copolymer.
Claim 11
Independent Claim
20 words
A method as claimed in any one of claims 6 to 8 in which the further alpha olefin is propylene
Claim 12
Independent Claim
20 words
A method as claimed in any one of claims 6 to 8 in which the further alpha olefin is butene-1.
Claim 13
Dependent Claim
14 words
A method as claimed in claim 6 substantially as hereinbefore described in the Example.
Claim 14
Dependent Claim
23 words
1 2 . A heat-sealable oriented polypropylene film when manufactured by a method as claimed in any one of claims 6 to 11.
References Cited (Backward Citations)
No citation records indexed.
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