US4409286A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite thermoplastic films and a process for their preparation
Assignee: Orkem SA
•
Filing: 1982-05-17
•
Granted: 1983-10-11
•
Expires: 2002-05-17
Abstract
Abstract A composite film for packaging foods having at least one layer of a thermoplastic film of low density polyethylene, polypropylene, polybutene, polyamide, polystyrene or polyvinyl chloride having a thickness between 25 and 3,000 mu m, and another layer of a terpolymer film having a thickness between 10 and 100 mu m. The terpolymer film contains from 88 to 98.7 mol % of units derived from ethylene, from 1 to 10 mol % of units derived from an ester of an alkyl acrylate or an alkyl methacrylate, the alkyl group having from 1 to 6 carbon atoms, and from 0.3 to 3 mol % of units derived from maleic anhydride.
Inventors
- 👤 Jean-Claude Decroix
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:51
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/30; B32B27/308; B32B27/32; B32B27/322; B32B2553/00; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/26; Y10T428/31504; Y10T428/31725; Y10T428/3175; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192; Y10T428/31931
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
102 words
A composite film consisting essentially of at least one layer of a thermoplastic film having a thickness of from 25 to 3,000 μm and selected from the group consisting of low density polyethylene, polypropylene, polybutene, polyamide, polystyrene and polyvinyl chloride and a layer of a terpolymer film comprising from 88 to 98.7 mol% of units derived from ethylene, from 1 to 10 mol% of units derived from an ester selected from the group consisting of alkyl acrylates and alkyl methacrylates, the alkyl group having from 1 to 6 carbon atoms, and from 0.3 to 3 mol% of units derived from maleic anhydride.
Claim 2
Dependent Claim
102 words
A composite film consisting essentially of at least one layer of a thermoplastic film having a thickness of from 25 to 3,000 μm and selected from the group consisting of low density polyethylene, polypropylene, polybutene, polyamide, polystyrene and polyvinyl chloride and a layer of a terpolymer film comprising from 88 to 98.7 mol% of units derived from ethylene, from 1 to 10 mol% of units derived from an ester selected from the group consisting of alkyl acrylates and alkyl methacrylates, the alkyl group having from 1 to 6 carbon atoms, and from 0.3 to 3 mol% of units derived from maleic anhydride.
Claim 3
Dependent Claim
55 words
A composite film according to claim 1 in which the terpolymer additionally contains up to 5 mol% of a fourth monomer selected from the group consisting of α-olefins having from 3 to 8 carbon atoms, alkyl monomaleates and dialkyl maleates, whose alkyl groups have from 1 to 6 carbon atoms, vinyl acetate and carbon monoxide.
Claim 4
Dependent Claim
19 words
A composite film according to claim 1 in which the polydispersity index of the terpolymer is greater than 6.
Claim 5
Dependent Claim
21 words
A composite film according to claim 1, in which the terpolymer has a melt index of between 1 and 10 dg/min.
Claim 6
Dependent Claim
27 words
A composite film according to one of claims 1 or 4 in which the terpolymer contains from 0.3 to 1 mol% of units derived from maleic anhydride.
Claim 7
Dependent Claim
45 words
A process for obtaining the composite film of claim 1, comprising coextruding at a speed of travel of between 2 and 2,000 meters per minute, a film of the terpolymer and a film of the thermoplastic at a temperature of between 140° and 260° C.
Claim 8
Dependent Claim
23 words
The process of claim 6 wherein the films are coextruded through a cylindrical die with a blow-up ratio of between 1 and 4.
Claim 9
Dependent Claim
14 words
The process of claim 6, wherein the films are coextruded through a flat die.
References Cited (Backward Citations)
FR1323379A
Cited
US4302511A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-10 | 1987-04-11 | 1987-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-10 | 1991-04-11 | 1991-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-10 | 1995-04-11 | 1995-10-11 | $7700.00 | Window Closed / Lapsed |