US2609318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicon carbide refractory article
Assignee: Unifrax I LLC
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Filing: 1949-12-08
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Granted: 1952-09-02
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Expires: 1969-12-08
Abstract
No abstract record available.
Inventors
- 👤 John P Swentzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:11
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/6303; C04B35/6316; C04B35/515; C04B35/56; C04B35/565; F; F04; F04B; F04B15/00; F04B15/04; Y; Y10; Y10S; Y10S264/00; Y10S264/36; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
55 words
A BONDED SILICON CARBIDE REFRACTORY ARTICLE COMPRISING A SURFACE LAYER OF SILICON NITRIDEBONDED SILICON CARBIDE, THE SILICON NITRIDE THEREOF HAVING THE CHEMICAL FORMULA SI3N4, SAID SURFACE LAYER BEING INTEGRAL WITH A MAIN BODY PORTION COMPRISING SILICON CARBIDE BONDED BY SILICON NITRIDE OF THE CHEMICAL FORMULA SI3N4 AND CONTAINING 2 TO 25% OF IRON AND MANGANESE.
Claim 2
Dependent Claim
55 words
A BONDED SILICON CARBIDE REFRACTORY ARTICLE COMPRISING A SURFACE LAYER OF SILICON NITRIDEBONDED SILICON CARBIDE, THE SILICON NITRIDE THEREOF HAVING THE CHEMICAL FORMULA SI3N4, SAID SURFACE LAYER BEING INTEGRAL WITH A MAIN BODY PORTION COMPRISING SILICON CARBIDE BONDED BY SILICON NITRIDE OF THE CHEMICAL FORMULA SI3N4 AND CONTAINING 2 TO 25% OF IRON AND MANGANESE.
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) | 1955-09-02 | 1956-03-03 | 1956-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-09-02 | 1960-03-03 | 1960-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-09-02 | 1964-03-03 | 1964-09-02 | $7700.00 | Window Closed / Lapsed |