EP0351744A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Improved very low density polyethylene film from blends
Assignee: Viskase Corp
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Filing: 1989-07-15
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Granted: —
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Expires: 2009-07-15
Abstract
Abstract Biaxially stretched monolayer and multilayer films comprising blends of a 1-butene very low density polyethylene with a 1-hexene very low density polyethylene have expectedly good puncture resistance and machine direction shrink force.
Inventors
- 👤 Edwin Rogers Smith
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 16:28
CPC Classifications
C; C08; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0807; C08L23/0815; C08J; C08J5/00; C08J5/18; B; B29; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2023/0608; B29K2023/0616; B29K2023/08; B29K2023/083; C08J2323/00; C08J2323/02; C08J2323/04; C08J2323/08; C08L2205/00; C08L2205/02; C08L23/0846; C08L23/0853; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/13; Y10T428/1328; Y10T428/1352; Y10T428/1379; Y10T428/1383; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192; Y10T428/31928
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
70 words
A biaxially stretched flexible film comprising a blend of (a) a VLDPE copolymer of ethylene and 1-butene having a density less than .915 g/cc, and a Vicat softening point of at least 70°C, a melting point greater than 100°C, and (b) a VLDPE copolymer of ethylene and 1-hexene having a density less than .915 g/cc, a Vicat softening point of at least 70°C and a melting point greater than 100°C.
Claim 2
Dependent Claim
70 words
A biaxially stretched flexible film comprising a blend of (a) a VLDPE copolymer of ethylene and 1-butene having a density less than .915 g/cc, and a Vicat softening point of at least 70°C, a melting point greater than 100°C, and (b) a VLDPE copolymer of ethylene and 1-hexene having a density less than .915 g/cc, a Vicat softening point of at least 70°C and a melting point greater than 100°C.
Claim 3
Dependent Claim
31 words
A biaxially stretched flexible film, as defined in claim 1, wherein said components (a) and (b) are present in said blend in an a:b weight ratio of from 1:7 to 3:1.
Claim 4
Dependent Claim
31 words
A biaxially stretched flexible film, as defined in claim 1, wherein said components (a) and (b) are present in said blend in an a:b weight ratio of from 1:4 to 3:1.
Claim 5
Dependent Claim
24 words
A biaxially stretched flexible film, as defined in claim 1, wherein said ratio of component (a) to component (b) is from 1:4 to 1:2.
Claim 6
Dependent Claim
22 words
A biaxially stretched flexible film, as defined in claim 1, wherein said ratio of component (a) to component (b) is about 1:3.
Claim 7
Dependent Claim
43 words
A biaxially stretched flexible film, as defined in claim 1, wherein component (a) is present in an amount of from about 20 to about 75 weight percent and component (b) is present in an amount from about 25 to about 80 weight percent.
Claim 8
Dependent Claim
35 words
A biaxially stretched flexible film, as defined in claim 1, wherein component (a) is present in an amount of about 25 weight percent and component (b) is present in an amount of 75 weight percent.
Claim 9
Dependent Claim
33 words
A biaxially stretched flexible film, as defined in claim 1, wherein said film has at least about 15% shrinkage in the machine direction and at least about 20% shrinkage in the transverse direction.
Claim 10
Dependent Claim
43 words
A biaxially stretched flexible film, as defined in claim 1, wherein said film has a residual shrink force in the machine direction that is greater than that for a similar film comprising component (a) without component (b) or component (b) without component (a).
Claim 11
Dependent Claim
40 words
A biaxially stretched flexible film, as defined in claim 1, wherein said film has a puncture resistance which is greater than the puncture resistance for similar films made from components (a) without component (b) or component (b) without component (a).
Claim 12
Dependent Claim
18 words
A biaxially stretched flexible film, as defined in claim 1, wherein said blend further comprises ethylene-vinyl acetate copolymer.
Claim 13
Dependent Claim
21 words
A biaxially stretched flexible film, as defined in claim 11, wherein at least 50 wt% of said film comprises VLDPE polymers.
Claim 14
Dependent Claim
18 words
A biaxially stretched flexible film, as defined in claim 1, further comprising at least one additional coextruded layer.
Claim 15
Dependent Claim
34 words
A biaxially stretched flexible film, as defined in claim 5, wherein said film has a puncture resistance which is greater than the puncture resistance for unblended films comprising either component (a) or component (b).
Claim 16
Dependent Claim
37 words
A biaxially stretched flexible film, as defined in claim 4, wherein said film has a residual shrink force in the machine direction that is greater than that for an unblended film of component (a) or (b) alone.
Claim 17
Dependent Claim
20 words
A biaxially stretched flexible film, as defined in claim 5, further comprising between about 20-40 wt% of ethylene-vinyl acetate copolymer.
Claim 18
Dependent Claim
65 words
A biaxially stretched flexible film, as defined in claim 4, wherein said film has at least about 20% shrinkage in the machine direction, at least about 25% shrinkage in the transverse direction, a puncture resistance greater than the unblended film of component (a) or (b), and a residual shrink force in the machine direction greater than that for unblended films of component (a) or (b).
Claim 19
Dependent Claim
21 words
A biaxially stretched flexible film, as defined in claim 13, wherein said at least one additional coextruded layer is biaxially oriented.
Claim 20
Dependent Claim
33 words
A biaxially stretched flexible film, as defined in claim 13, wherein said at least one additional coextruded layer comprises an oxygen barrier intermediate layer and an outer layer of linear low density polyethylene.
Claim 21
Dependent Claim
84 words
A biaxially stretched multilayer film comprising: an inner layer of a blend of (a) a VLDPE copolymer of ethylene and 1-butene having a density between 0.860 and 0.915 g/cc and (b) a VLDPE copolymer of ethylene and 1-hexene having a density between about 0.860 and 0.915 g/cc, wherein said inner layer blend is in a weight percent ratio of (a) to (b) of from 1:7 to 3:1; an outer layer of VLDPE, LLDPE, LDPE, HDPE or blends thereof; and an intermediate oxygen barrier layer.
Claim 22
Dependent Claim
84 words
A biaxially stretched multilayer film comprising: an inner layer of a blend of (a) a VLDPE copolymer of ethylene and 1-butene having a density between 0.860 and 0.915 g/cc and (b) a VLDPE copolymer of ethylene and 1-hexene having a density between about 0.860 and 0.915 g/cc, wherein said inner layer blend is in a weight percent ratio of (a) to (b) of from 1:7 to 3:1; an outer layer of VLDPE, LLDPE, LDPE, HDPE or blends thereof; and an intermediate oxygen barrier layer.
References Cited (Backward Citations)
No citation records indexed.
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