Patent EP0317237A2 successfully refreshed from Google Patents.
EP0317237A2
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A polyethylene composite film
Assignee: Tonen General Sekiyu KK
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Filing: 1988-11-14
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Granted: —
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Expires: 2008-11-14
Abstract
Abstract A polyethylene composite film suitable for packing, which is superior in moistureproofness, flex-o-crack resistance, tearability and heat-sealing property, is provided comprising an oriented polyethylene film in which the degree of cross-linking inwardly decreases across the thickness of the film and at least one lamination layer, provided on one side of the oriented polyethylene film, consisting of a lamination material having a heat shrinkage of less than 5% at 120 C.
Inventors
- 👤 Yasushi Itaba
- 👤 Yutaka Yoshifuji
- 👤 Takayoshi Kondo
- 👤 Minoru Izawa
- 👤 Ichiro Sakamoto
- 👤 Tadao Yoshino
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 21:46
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/28; B32B27/32; B32B2255/00; B32B2255/10; B32B2255/20; B32B2255/205; B32B2307/00; B32B2307/50; B32B2307/514; B32B2323/00; B32B2323/04; B32B2323/046; B32B2439/00; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/13; Y10T428/1328; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/31504; Y10T428/31678; Y10T428/31692; Y10T428/31721; Y10T428/31725; Y10T428/31739; Y10T428/31743; Y10T428/31746; Y10T428/31786; Y10T428/31797; Y10T428/31855; Y10T428/3188; Y10T428/31884; Y10T428/31888; Y10T428/31895; Y10T428/31899; Y10T428/31902; Y10T428/31909; Y10T428/31913; Y10T428/31938
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
56 words
A polyethylene composite film comprising an oriented polyethylene film in which the degree of crosslinking inwardly decreases across the thickness of the film and at least one lamination layer, provided on one side of the oriented polyethylene film, said lamination layer consisting of a lamination material having a heat shrinkage of less than 5% at l20°C.
Claim 2
Dependent Claim
56 words
A polyethylene composite film comprising an oriented polyethylene film in which the degree of crosslinking inwardly decreases across the thickness of the film and at least one lamination layer, provided on one side of the oriented polyethylene film, said lamination layer consisting of a lamination material having a heat shrinkage of less than 5% at l20°C.
Claim 3
Dependent Claim
23 words
The polyethylene composite film as claimed in claim 1, wherein the lamination layer is provided, on the surface thereof, with a sealant layer.
Claim 4
Dependent Claim
38 words
The polyethylene composite film as claimed in claim 1, wherein the lamination layer is provided, on the surface thereof, with an oriented polyethylene film such that the degree of crosslinking inwardly decreases across the thickness of the film.
Claim 5
Dependent Claim
25 words
The polyethylene composite film as claimed in claim 1, wherein the oriented polyethylene film is provided, on the other side thereof, with a sealant layer.
Claim 6
Dependent Claim
69 words
The polyethylene composite film as claimed in any preceding claim, wherein the oriented polyethylene film is crosslinked to form a structure of a crosslinked layer/uncrosslinked layer/crosslinked layer across the thickness of the film, the crosslinked layer having a gel fraction of 20 to 70% and the uncrosslinked layer having a gel fraction of 0%, and the ratio of the uncrosslinked layer: crosslinked layer being 1 : 0.1 to 10.
Claim 7
Dependent Claim
34 words
The polyethylene composite film as claimed in any preceding claim, wherein the oriented polyethylene film is obtained by stretching a stock sheet with a draw ratio of at least 3 times in one direction.
Claim 8
Dependent Claim
65 words
The polyethylene composite film as claimed in any preceding claim, wherein the oriented polyethylene film has a water vapor transmission rate (Y) of lower than a numerical value obtained from the following formula, Y = 17X -1/2 in which Y represents the water vapor transmission rate (g/m²/24 hours) and X represents the thickness (µm) of the oriented film, and a haze of at most 5%.
Claim 9
Dependent Claim
23 words
The polyethylene composite film as claimed in any preceding claim, wherein the oriented polyethylene film has a thickness of 10 to 200 µm.
Claim 10
Dependent Claim
55 words
The polyethylene composite film as claimed in any preceding claim, wherein the oriented polyethylene film is based on a polyethylene having a density of at least 0.935 g/cm³, a melt index of 0.5 to 20 g/10 min and a ratio of high load melt index to melt index in the range of 40 to 200.
Claim 11
Dependent Claim
23 words
The polyethylene composite film as claimed in any preceding claim, wherein the oriented polyethylene film is based on a linear low density polyethylene.
Claim 12
Dependent Claim
53 words
The polyethylene composite film as claimed in any preceding claim, wherein (a) the oriented polyethylene film is previously subjected to vapor deposition with aluminum, or (b) the oriented polyethylene film is previously subjected to coating with polyvinylidene chloride or (c) the oriented polyethylene film is blended with a petroleum resin of hydrogenation type.
Claim 13
Dependent Claim
28 words
The polyethylene composite film as claimed in any preceding claim, wherein the crosslinking is carried out by irradiating both the surfaces of a stock sheet with electron beam.
Claim 14
Dependent Claim
24 words
The polyethylene composite film as claimed in any preceding claim, wherein the lamination material has a heat shrinkage of at most 5% at l40°C.
Claim 15
Dependent Claim
48 words
The polyethylene composite film as claimed in any preceding claim, wherein the lamination material is either selected from the group consisting of papers, aluminum foils, cellophanes or is a heat resisting resin selected from a group consisting of polyesters, polyamides, polyimides, polyparabanic acids, ethylene-vinyl alcohol copolymers and polypropylene.
Claim 16
Dependent Claim
22 words
The polyethylene composite film as claimed in any preceding claim, wherein the lamination layer has a thickness of 7 to 50 µm.
Claim 17
Dependent Claim
46 words
The polyethylene composite film as claimed in claims 2 or 4 and claims 5 to 15, wherein the sealant layer consists of a material selected from the group consisting of low density polyethylenes, linear low density polyethylenes, ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, ionomers and polypropylenes.
Claim 18
Dependent Claim
28 words
The polyethylene composite film as claimed in claims 2 or 4 and claims 5 to 16, wherein the sealant layer has a thickness of 10 to 50 µm.
Claim 19
Dependent Claim
22 words
The polyethylene composite film as claimed in claim 1, wherein the composite film has a thickness of about 20 to 300 µm.
Claim 20
Dependent Claim
16 words
A bag or vessel composed of the polyethylene composite film as claimed in any preceding claim.
References Cited (Backward Citations)
No citation records indexed.
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