Patent US4906538A successfully refreshed from Google Patents.
EP0756931A2
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Multilayer film
Assignee: Kureha Corp
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Filing: 1996-07-25
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Granted: —
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Expires: 2016-07-25
Abstract
Abstract A flexible multilayer film suitable as a (food-)packaging material includes a first seal layer comprising principally a metallocene-catalyzed polyolefin, and a second seal layer comprising a copolymer of at least one oxygen-containing monomer and ethylene. The copolymer is set to have a crystal melting point lower than that of the metallocene-catalyzed polyolefin. The second seal layer may preferably have a thickness larger than that of the first seal layer. Because of the provision of the second seal layer adjacent to the first seal layer, the multilayer film is provided with an improved film-formability while retaining the good sealability of the metallocene-catalyzed polyolefin.
Inventors
- 👤 Hajime Tsukamoto
- 👤 Ichiro Kitada
- 👤 Yoshiharu Nishimoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 21:50
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B7/00; B32B7/02; B32B7/027; B32B27/32; B32B27/327; B32B2307/00; B32B2307/70; B32B2307/724; B32B2307/7242; B32B2307/732; B32B2307/734; B32B2307/736; B32B2309/00; B32B2309/08; B32B2309/10; B32B2309/105; B32B2439/00; B32B2439/70; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/13; Y10T428/131; Y10T428/1317; Y10T428/1321; Y10T428/1324; Y10T428/1334; Y10T428/1352; Y10T428/1355; Y10T428/1359; Y10T428/1379; Y10T428/1383; Y10T428/26; Y10T428/269; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
43 words
A multilayer film, including: a first seal layer comprising principally a metallocene-catalyzed polyolefin, and a second seal layer comprising a copolymer of at least one oxygen-containing monomer and ethylene; said copolymer having a crystal melting point lower than that of the metallocene-catalyzed polyolefin.
Claim 2
Dependent Claim
23 words
A multilayer film according to Claim 1, wherein the second seal layer has a thickness larger than that of the first seal layer.
Claim 3
Dependent Claim
53 words
A multilayer film according to Claim 1 or 2, wherein the first seal layer comprises a mixture of at least 50 wt. % of the metallocene-catalyzed polyolefin and another metallocene-catalyzed polyolefin, and the second seal layer comprises a mixture of a largest amount of the copolymer and a smaller amount of another resin.
Claim 4
Dependent Claim
24 words
A multilayer film according to any of Claims 1 - 3, having a secant modulus at 2.5 % strain of 150 - 450 MPa.
Claim 5
Dependent Claim
21 words
A multilayer film according to any preceding claim, wherein the second seal layer has been crosslinked by irradiation with electron rays.
Claim 6
Dependent Claim
16 words
A multilayer film according to any preceding claim, wherein said metallocene-catalyzed polyolefin is an ethylene-based resin.
Claim 7
Dependent Claim
24 words
A multilayer film according to any preceding claim, wherein said metallocene-catalyzed polyolefin has a weight-average molecular weight (Mw)/number-average molecular weight (Mn) ratio below 3.
Claim 8
Dependent Claim
48 words
A multilayer film according to any preceding claim, wherein said metallocene-catalyzed polyolefin is a mixture of a metallocene-catalyzed polyolefin having a crystal melting point of 105 - 145 o C and a metallocene-catalyzed polyolefin having a crystal melting point of 70 o C to below 105 o C.
Claim 9
Dependent Claim
56 words
A multilayer film according to any preceding claim, wherein said second seal layer comprises a copolymer of 80 - 95 wt. % of ethylene and up to 20 wt. % of at least one monomer selected from the group consisting of vinyl acetate, acrylic acid, methyl acrylate, acrylic acid, methyl acrylate, ethyl acrylate and butyl acrylate.
Claim 10
Dependent Claim
39 words
A multilayer film according to any preceding claim, comprising at least three layers further including an outermost layer of a thermoplastic resin disposed on an opposite side of the first seal layer with respect to the second seal layer.
Claim 11
Dependent Claim
14 words
A multilayer film according to any preceding claim, further including a gas barrier layer.
Claim 12
Dependent Claim
11 words
A multilayer film according to any preceding claim, having a heat-shrinkability.
Claim 13
Dependent Claim
29 words
A blown plastic container comprising a multilayer film according to any one of Claims 1 - 12 so that the first seal layer is disposed as an innermost layer.
Claim 14
Dependent Claim
17 words
A container according to Claim 13, wherein the first seal layer has been hermetically-sealed to each other.
Claim 15
Dependent Claim
51 words
A packaged product, comprising a blown plastic container comprising a multilayer film according to any one of Claims 1 - 12 so that the first seal layer is disposed as an innermost layer, and a content material packed within the container by sealing the innermost first seal layer to each other.
Claim 16
Dependent Claim
13 words
A packaged product according to Claim 15, wherein the content material comprises food.
Claim 17
Dependent Claim
12 words
A packaged product according to Claim 16, wherein the food comprises meat.
References Cited (Backward Citations)
JPS59143639A
Cited
JPH068383A
Cited
JPH06210810A
Cited
JPH06166157A
Cited
JPH06320685A
Cited
JPH071680A
Cited
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