EP0144999A2
Expired / Lapsed
EP
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Coextrusion multi-layer tubular film
Assignee: Idemitsu Petrochemical Co Ltd
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Filing: 1984-12-08
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Granted: —
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Expires: 2004-12-08
Abstract
Abstract This invention provides a coextrusion multi-layer tubler film which is superior in mechanical strength and transparency, and is free from curling. The coextrusion multi-layer tubler film comprises an outer layer made of a linear ethylene α-olefin copolymer having a density of from 0.900 to 0.945 gram per cubic centimeter and an inner layer made of a polypropylene-based resin or a resin composition comprising a polypropylene-based resin and an ethylene a-olefin copolymer having a density of from 0.850 to 0.945 gram per cubic centimeter.
Inventors
- 👤 Masakatsu Kimura
- 👤 Osamu Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 22:49
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/32; B32B1/00; B32B1/08; B29; B29C; B29C48/00; B29C48/03; B29C48/09; B29C48/10; B29C48/14; B29C48/147; B29C48/1472; B32B27/06; B32B27/08; B32B27/322; C; C08; C08L; C08L23/00; C08L23/02; C08L23/10; C08L23/12; B29C2791/00; B29C2791/004; B29C2791/007; B32B2307/00; B32B2307/70; B32B2307/72; B32B2323/00; B32B2323/10; B32B2439/00; B32B2439/70; C08L23/04; C08L23/08; C08L23/0807; C08L23/0815; C08L23/16; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1334; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
62 words
A coextrusion multi-layer tubular film comprising: an outer layer made of a linear ethylene a-olefin copolymer having a density of from 0.900 to 0.945 gram per cubic centimeter; and an inner layer made of a polypropylene-based resin or a resin composition comprising a polypropylene-based resin and an ethylene a-olefin copolymer having a density of from 0.850 to 0.945 gram per cubic centimeter.
Claim 2
Dependent Claim
62 words
A coextrusion multi-layer tubular film comprising: an outer layer made of a linear ethylene a-olefin copolymer having a density of from 0.900 to 0.945 gram per cubic centimeter; and an inner layer made of a polypropylene-based resin or a resin composition comprising a polypropylene-based resin and an ethylene a-olefin copolymer having a density of from 0.850 to 0.945 gram per cubic centimeter.
Claim 3
Dependent Claim
21 words
The film as claimed in Claim 1, wherein the ratio of outer layer and inner layer is from 50:50 to 97:3.
Claim 4
Dependent Claim
35 words
The film as claimed in Claim 1, wherein the linear ethylene a-olefin copolymer constituting the outer layer contains from 1 to 20 percent by weight of an a-olefin having from 3 to 20 carbon atoms.
Claim 5
Dependent Claim
33 words
The film as claimed in Claim 1, wherein the polypropylene-based resin is propylene homopolymer, block or random copolymer of propylene and 20 percent by weight or less of one or more other a-olefins.
Claim 6
Dependent Claim
52 words
The film as claimed in Claim 1, wherein the ethylene a-olefin copolymer constituting the resin composition of inner layer is a lenear ethylene a-olefin copolymer containing from 1 to 20 percent by weight of an a-olefin having from 3 to 20 carbon atoms or an ethylene a-olefin copolymer of low- or non-crystallinity.
Claim 7
Dependent Claim
30 words
The film as claimed in Claim 5, wherein the ethylene a-olefin copolymer of low- or non-crystallinity is the copolymers of ethylene and a-olefins having from 3 to 12 carbon atoms.
Claim 8
Dependent Claim
27 words
The film as claimed in Claim 5, wherein the ethylene a-olefin copolymer is the copolymer having a density of from 0.850 to 0.910 gram per cubic centimeter.
Claim 9
Dependent Claim
41 words
The film as claimed in Claim 1, wherein the resin composition for the inner layer is composed of from 60 to 98 percent by weight of polypropylene based resin and from 40 to 2 percent by weight of ethylene a-olefin copolymer.
References Cited (Backward Citations)
No citation records indexed.
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