US3671221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Foamed metal
Assignee: Ethyl Corp
•
Filing: 1970-10-30
•
Granted: 1972-06-20
•
Expires: 1990-10-30
Abstract
Abstract FOAMED METALS HAVING IMPROVED CELLULAR STRUCTURE ARE PRODUCED BY MELTING A METAL, ADDING DROSS TO THE MOLTEN METAL, AND FOAMING THE MOLTEN BY MEANS OF A HEAT DECOMPOSABLE FOAMING AGENT.
Inventors
- 👤 Currie B Berry Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:03
CPC Classifications
C; C22; C22C; C22C1/00; C22C1/08; C22C1/083
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |