US3637458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microcellular foam sheet
Assignee: Ametek Aerospace Products Inc
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Filing: 1968-12-27
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Granted: 1972-01-25
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Expires: 1988-12-27
Abstract
Abstract A low-density foam sheet of a high work-to-break value thermoplastic crystalline polymer comprising polyhedral-shaped closed cells having a median diameter of at least 500 microns and a process for its preparation by flash extrusion with reduced bubble nuclei formation.
Inventors
- 👤 Robert Guy Parrish
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:09
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249954; Y10T428/249975; Y10T428/249976; Y10T428/249977; Y10T428/249982; Y10T428/249985; Y10T428/249987; Y10T428/249991; Y10T428/31504; Y10T428/31855; Y10T428/31909
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
43 words
A foam sheet of claim 1 wherein the median diameter of said closed cells is at least 1,000 microns, said cells have a wall thickness of from about 0.5 to about 3.0 microns and wherein said cells are substantially fully reinflated with air.
Claim 2
Dependent Claim
13 words
A foam sheet of claim 1 having a maximum density of 0.015 g./cc.
Claim 3
Dependent Claim
12 words
A foam sheet of claim 1 wherein said polymer is a polyhydrocarbon.
Claim 4
Dependent Claim
12 words
A foam sheet of claim 1 wherein said polymer is isotactic polypropylene.
Claim 5
Dependent Claim
12 words
A foam sheet of claim 1 wherein said polymer is linear polyethylene.
Claim 6
Dependent Claim
14 words
A foam sheet of claim 1 having at least one polymeric film bonded thereto.
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) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |