US3645837A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laminates
Assignee: Dow Chemical Co
•
Filing: 1970-08-14
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Granted: 1972-02-29
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Expires: 1990-08-14
Abstract
Abstract Plastic film or sheet having a plurality of layers is formed by deforming a flowing stream having layers of diverse thermoplastic material to provide a sheet or film having a laminar structure. Alternating foamed and unfoamed layers are obtained.
Inventors
- 👤 Douglas S Chisholm
- 👤 Walter J Schrenk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:00
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/20; B29C44/22; B29C48/00; B29C48/03; B29C48/07; B29C48/08; B29C48/16; B29C48/18; B29C48/21; B29C48/25; B29C48/30; B29C48/305; B29C48/307; B29C48/36; B29C48/49; B29C48/495; B29C48/50; B29C48/695; B29C48/70; B29C48/705; B29C48/71; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/249921; Y10T428/249953; Y10T428/249981; Y10T428/249987; Y10T428/249991; Y10T428/249992; Y10T428/249993; Y10T428/26; Y10T428/266; Y10T428/269; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31928
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
15 words
The article of claim 1 wherein there are from about 10 to 1, 000 layers.
Claim 2
Dependent Claim
16 words
The article of claim 1 wherein the major surfaces are layers of solid thermoplastic resinous film.
Claim 3
Dependent Claim
27 words
The article of claim 1 wherein the solid thermoplastic resinous film has a high elongation before breaking relative to the elongation before breaking of the foam component.
Claim 4
Dependent Claim
18 words
The article of claim 4 wherein the solid polymer is polyethylene and the expandable cellular resin is polystyrene.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |