US3084998A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making foamed silicon nitride
Assignee: Union Carbide Corp
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Filing: 1960-12-20
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Granted: 1963-04-09
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Expires: 1980-12-20
Abstract
No abstract record available.
Inventors
- 👤 Howard M Dess
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:20
CPC Classifications
C; C04; C04B; C04B38/00; C04B38/0022; C04B38/0025; C01; C01B; C01B21/00; C01B21/06; C01B21/068; C01B21/0682; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/591; C04B38/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
61 words
A PROCESS FOR THE PRODUCTION OF POROUS SILICON NITRIDE COMPRISING MIXING FINELY-DIVIDED SILICON HAVING AN OXIDIC SILICON FILM, WITH AQUEOUS HYDROFLUORIC ACID, THE AMOUNT OF FINELY-DIVIDED SILICON BEING SUBSTANTIALLY IN EXCESS OF THAT WHICH WILL REACT WITH SAID HYDROFLUORIC ACID, WHEREBY A STABLE FOAM IS FORMED; DRYING SAID FOAM; AND NITRIDING THE FOAM TO CONVERT IT TO SUBSTANTIALLY PURE SILICON NITRIDE.
Claim 2
Dependent Claim
61 words
A PROCESS FOR THE PRODUCTION OF POROUS SILICON NITRIDE COMPRISING MIXING FINELY-DIVIDED SILICON HAVING AN OXIDIC SILICON FILM, WITH AQUEOUS HYDROFLUORIC ACID, THE AMOUNT OF FINELY-DIVIDED SILICON BEING SUBSTANTIALLY IN EXCESS OF THAT WHICH WILL REACT WITH SAID HYDROFLUORIC ACID, WHEREBY A STABLE FOAM IS FORMED; DRYING SAID FOAM; AND NITRIDING THE FOAM TO CONVERT IT TO SUBSTANTIALLY PURE SILICON NITRIDE.
References Cited (Backward Citations)
US2618565A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-04-08 | 1966-10-08 | 1967-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-04-08 | 1970-10-08 | 1971-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-04-08 | 1974-10-08 | 1975-04-09 | $7700.00 | Window Closed / Lapsed |