Patent US4741957A successfully refreshed from Google Patents.
US4741957A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat sealable multilayer film and method of making same
Assignee: Mobil Oil AS
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Filing: 1986-09-02
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Granted: 1988-05-03
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Expires: 2006-09-02
Abstract
Abstract An oriented polyolefin film structure having a base layer of, for example, polypropylene, and wherein at least one skin layer is comprised of a copolymer or terpolymer and at least one skin layer is comprised of a polyamide, polyester or polycarbonate polymer whereby said film structure has improved and broad heat sealability.
Inventors
- 👤 Hee C. Park
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:57
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/32; B32B27/34; B32B27/36; B32B27/365; B32B2250/00; B32B2250/24; B32B2307/00; B32B2307/30; B32B2307/31; B32B2307/50; B32B2307/514; B32B2307/518; B32B2323/00; B32B2323/04; B32B2323/10; B32B2367/00; B32B2369/00; B32B2377/00; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/28; Y10T428/2813; Y10T428/2817; Y10T428/2826; Y10T428/31504; Y10T428/31507; Y10T428/31725; Y10T428/3175; Y10T428/31786; Y10T428/31797; Y10T428/31855; Y10T428/31909; Y10T428/31913
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
119 words
An improved oriented broad heat sealable three-layer coextruded structure comprising: (a) a heat sealable layer consisting essentially of a low temperature melting resin having a low softening point, high seal and hot tack strength on at least one surface; (b) a substrate comprising a polyolefin and (c) a surface active layer on at least one surface of (b) selected from high temperature stable polymers and wherein (a) has a thickness varying from about 3 to about 20 wt.% of the layered film structure, (b) has a thickness of from about 60 to about 90 percent of the total layered film structure and (c) has a thickness varying from about 7 to about 20 wt.% of the layered film structure.
Claim 2
Dependent Claim
119 words
An improved oriented broad heat sealable three-layer coextruded structure comprising: (a) a heat sealable layer consisting essentially of a low temperature melting resin having a low softening point, high seal and hot tack strength on at least one surface; (b) a substrate comprising a polyolefin and (c) a surface active layer on at least one surface of (b) selected from high temperature stable polymers and wherein (a) has a thickness varying from about 3 to about 20 wt.% of the layered film structure, (b) has a thickness of from about 60 to about 90 percent of the total layered film structure and (c) has a thickness varying from about 7 to about 20 wt.% of the layered film structure.
Claim 3
Dependent Claim
11 words
The structure of claim 1 wherein said polyolefin comprises homopolymer polypropylene.
Claim 4
Dependent Claim
20 words
The structure of claim 1 wherein said low temperature melting resin (a) is selected from copolymers, terpolymers and mixtures thereof.
Claim 5
Dependent Claim
21 words
The structure of claim 3 wherein said resin is selected from the group consisting of ethylene/propylene random copolymers and ethylene/propylene/butene terpolymers.
Claim 6
Dependent Claim
22 words
The structure of claim 1 wherein the high temperature polymer (c) is selected from polymers having polyamide, polyethylene terphthalate or polycarbonate groups.
Claim 7
Dependent Claim
12 words
The structure of claim 1 having an orientation greater than 4 times.
Claim 8
Dependent Claim
18 words
The structure of claim 2 wherein (a) is an ethylene/propylene/butene-1 terpolymer and (c) is a polyethylene terephthalate polymer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-03 | 1991-11-02 | 1992-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-03 | 1995-11-02 | 1996-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-03 | 1999-11-02 | 2000-05-03 | $7700.00 | Window Closed / Lapsed |