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US4701496A Expired / Lapsed US ⏱️ 0.0 years remaining

Composition for drawn film, cold drawn film made of said composition and process for manufacture of said film

Assignee: Asahi Dow Ltd
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Filing: 1986-02-03
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Granted: 1987-10-20
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Expires: 2006-02-03
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Abstract

Abstract A composition for shrinkable film which excels in heat-sealability, transparency, strength, and particularly low-temperature quick shrinking property and, therefore, suits production chiefly of packaging materials, a film made of the composition and a process for the manufacture of the film are disclosed. Specifically, the composition comprises one of the specific combinations of components (A), (B) and (C), i.e. the combinations of (A)+(B), (B)+(C) and (A)+(B)+(C), wherein (A) is non-rigid polyolefine resins such as ethylene vinyl acetate, (B) is an elastomer comprising a specific ethylene-α-olefin copolymer, and (C) is rigid polyolefin resins such as polypropylene. The packaging film excelling particularly in optical property, mechanical strength and low-temperature shrinking property is obtained by converting a homogeneous blend of the aforementioned composition, either in its crosslinked form or in its non-crosslinked form, into a tubular raw film, which is stretched at a temperature low enough for imparting a high orientation to the film. The process for the manufacture of this packaging film is also disclosed.

Inventors

  • 👤 Isao Yoshimura
  • 👤 Hideo Hata
  • 👤 Takashi Kaneko

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 18:16
CPC Classifications
B; B29; B29C; B29C61/00; B29C61/003; C; C08; C08L; C08L23/00; C08L23/02; B29C48/00; B29C48/001; B29C48/0018; B29C48/03; B29C48/09; B29C48/10; C08L23/04; C08L23/08; C08L23/0846; C08L23/0853; C08L23/10; C08L23/16

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 53 words
A composition suitable to make a cold drawn film comprsing a homogenous blend of one of the specific combinations of components, namely the combinations of (A)+(B)+(C); wherein (A) is low-density polyethylene, (B) is an elastomer having a density of not more than 0.91 g/cm 3 and made of an ethylene-° -olefin compolymer, and
Claim 2
Dependent Claim 53 words
A composition suitable to make a cold drawn film comprsing a homogenous blend of one of the specific combinations of components, namely the combinations of (A)+(B)+(C); wherein (A) is low-density polyethylene, (B) is an elastomer having a density of not more than 0.91 g/cm 3 and made of an ethylene-° -olefin compolymer, and
Claim 3
Dependent Claim 25 words
(C) is a mixture of crystalline polypropylene and crystalline polybutene-1 and the ratios of the components are such as to statisy 0.07≦ B/(A+B)≦0.07 and 0.07≦C/(A+B)≦0.8.
Claim 4
Dependent Claim 25 words
(C) is a mixture of crystalline polypropylene and crystalline polybutene-1 and the ratios of the components are such as to statisy 0.07≦ B/(A+B)≦0.07 and 0.07≦C/(A+B)≦0.8.
Claim 5
Dependent Claim 33 words
The composition according to claim 1, wherein the ethylene-α-olefin copolymer as the component (B) has an ethylene group content of not more than 90 mol % and not less than 20 mol %.
Claim 6
Dependent Claim 33 words
The composition according to claim 1, wherein the ethylene-α-olefin copolymer as the component (B) has an ethylene group content of not more than 90 mol % and not less than 40 mol %.
Claim 7
Dependent Claim 63 words
The composition according to claim 1, wherein the elastomer as the component (B) is a non-rigid copolymer having a Vicat softening point of not more than 80° C. and a degree of crystallization of not more than 30%, wherein the α-olefin component contained therein is at least one member selected from the group consisting of α-olefin having from 3 to 12 carbon atoms.
Claim 8
Dependent Claim 44 words
The composition according to claim 1, wherein the component (B) is a thermoplastic elastomer random copolymer wherein the α-olefin component contained therein is selected from the group consisting of propylene and butene-1, and the coolymer possesses a melt index of from 0.1 to 10.
Claim 9
Dependent Claim 28 words
The composition according to claim 1, wherein the hylene-α-olefin copolymer as the component (B) has a polyene copolymerized in addition to the main mponents of ethylene and α-olefin
Claim 10
Dependent Claim 30 words
The composition according to claim 6, wherein the polyene contains not more than 5 mol % of a non-conjugate diene selected from the group consisting of hexadiene and norbornene derivatives.
Claim 11
Dependent Claim 25 words
The composition according to claim 1, wherein the component (C) is a rigid polymer having a Vicat softening point of not less than 100° C.

References Cited (Backward Citations)

US3256366A Cited
US3256367A Cited
GB1037819A Cited
US3562790A Cited
GB1114589A Cited
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US3758643A Cited
US3806558A Cited
US3846349A Cited
US3998911A Cited
US4087485A Cited
US4088714A Cited
US4113804A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-10-19 1991-04-20 1991-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-10-19 1995-04-20 1995-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-10-19 1999-04-20 1999-10-20 $7700.00 Window Closed / Lapsed

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