US3788866A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing refractory material
Assignee: Elkem ASA
•
Filing: 1972-10-02
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Granted: 1974-01-29
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Expires: 1992-10-02
Abstract
Abstract A METHOD OF PRODUCING SILICA REFRACTORY MATERIALS IS DISCLOSED. FINELY DIVIDED SILICA IS ADMIXED WITH WATER AND THEN LIME IS ADDED TO THE MIXTURE. THEREAFTER A PROPER AMMONIUM COMPOUND IS ADDED TO PRECIPITAT CALCIUM AS A COMPOUND INSOLUBLE IN WATER AFTER WHICH THE PRODUCT IS BAKED PREFERABLY FIRST AT A LOW TEMPERATURE FOR A RELATIVELY LONG PERIOD OF TIME AND THEN AT A HIGH TEMPERATURE FOR A SHORTER PERIOD OF TIME.
Inventors
- 👤 H Flood
- 👤 A Seltveit
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:37
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/14
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) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |