← Back to Patent Explorer
US4456646A Expired / Lapsed US ⏱️ 0.0 years remaining

Laminate film having a heat-shrinkage rate greater than 15 percent at 90° C.

Assignee: Kureha Corp
•
Filing: 1981-10-21
•
Granted: 1984-06-26
•
Expires: 2001-10-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Described is a laminate film excellent in oil-resistance, heat-resistant sealing ability, peel resistance and gas-barriering property having a percentage of heat-shrinkage of larger than 15% at 90° C. comprising a center layer consisting of a copolymer(I) of vinylidene chloride and both two outermost layers consisting of a mixture of 20 to 70% by weight of a copolymer(II) of ethylene and alpha-olefin of density of 0.900 to 0.950 and of crystalline melting point of 110° to 125° C. and 80 to 30% by weight of a copolymer(III) of ethylene and vinyl acetate with the proviso that the content of the copolymer(II) in the total amount of copolymers in both the two outermost layers is less than 65% by weight and showing a structure of having an adhesive layer between the center layer and the outermost layer.

Inventors

  • 👤 Yoshiharu Nishimoto
  • 👤 Kengo Yamazaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 06:21
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/30; B32B27/304; B32B27/32; B32B27/322; B32B7/00; B32B7/04; B32B7/12; B29; B29K; B29K2027/00; B29K2027/08; B32B2307/00; B32B2307/70; B32B2307/732; B32B2307/734; B32B2307/736; B32B2327/00; B32B2327/12; B32B2439/00; B32B2439/70; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/24975; Y10T428/31504; Y10T428/31855; Y10T428/31931; Y10T428/31935

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 117 words
A laminate film having a heat-shrinkage rate of greater than 15% at 90° C., comprising a center layer consisting of a copolymer (I) of vinylidene chloride; at least two outermost layers each consisting of a mixture of 20 to 70% by weight of copolymer(II) of ethylene and alpha-olefin having a crystalline melting point of 110° to 125° C., and 80 to 30% by weight of a copolymer(III) of ethylene and vinyl acetate having a crystalline melting point of 85° to 103° C., said copolymer(II) being less than 65% by weight of the total amount of copolymers (II) and (III) in both of the outermost layers; and an adhesive layer between the center layer and the outermost layers.
Claim 2
Dependent Claim 117 words
A laminate film having a heat-shrinkage rate of greater than 15% at 90° C., comprising a center layer consisting of a copolymer (I) of vinylidene chloride; at least two outermost layers each consisting of a mixture of 20 to 70% by weight of copolymer(II) of ethylene and alpha-olefin having a crystalline melting point of 110° to 125° C., and 80 to 30% by weight of a copolymer(III) of ethylene and vinyl acetate having a crystalline melting point of 85° to 103° C., said copolymer(II) being less than 65% by weight of the total amount of copolymers (II) and (III) in both of the outermost layers; and an adhesive layer between the center layer and the outermost layers.
Claim 3
Dependent Claim 35 words
A laminate film according to claim 1, wherein said copolymer(I) comprises 65 to 95% by weight of vinylidene chloride and 35 to 5% by weight of at least one unsaturated monomer copolymerizable with vinylidene chloride.
Claim 4
Dependent Claim 32 words
A laminate film according to claim 1, wherein said copolymer(II) is a copolymer of ethylene and one or more alpha-olefins selected from the group consisting of butene-1, pentene-1, 4-methylpentene-1, hexene-1 and octene-1.
Claim 5
Dependent Claim 31 words
A laminate film according to claim 1, wherein said copolymer(III) falls in the pentagonal range defined in FIG. 1 by linear lines connecting the points (W-1), (W-II), (X-II), and (Z-I), respectively.
Claim 6
Dependent Claim 38 words
A laminate film according to claim 1, wherein said adhesive layer comprises a polymer or a mixture of polymers selected from the group consisting of polyethylene modified by a carboxylic acid, a copolymer of ethylene and vinyl acetate.
Claim 7
Dependent Claim 26 words
A laminate film according to claim 1, or claim 5 wherein the thickness of said adhesive layer is in the range of 1 to 3 microns.

References Cited (Backward Citations)

US3524795A Cited
GB1379106A Cited
CA982923A Cited
US4096946A Cited
JPS5267842A Cited
US4161562A Cited
US4278738A Cited
US4352850A Cited
US4357376A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-06-26 1987-12-26 1988-06-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-06-26 1991-12-26 1992-06-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-06-26 1995-12-26 1996-06-26 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag