Patent US3573941A successfully refreshed from Google Patents.
US3573941A
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US
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Expanded magnesia cement
Assignee: BP Chemicals Ltd
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Filing: 1968-02-26
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Granted: 1971-04-06
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Expires: 1988-02-26
Abstract
Abstract AN EXPANDED MAGNESIA CEMENT CONTAINING A VOLUME OF GAS AT LEAST EQUAL TO THE VOLUME OF THE CEMENT IN ITS UNEXPANDED STATE. THE CEMENT IS FORMED BY MIXING MAGNESIUM OXIDE, MAGNESIUM CHLORIDE AND WATER IN THE PRESENCE OF A FOAM-FORMING SURFACE ACTIVE AGENT AND IN THE PRESENCE OF A FOAM STABILIZING WATER-SOLUBLE SILICONE, ENTRAINING A GAS INTO THE RESULTING MIX TO FORM A FLOWABLE FOAM AND ALLOWING THE FOAM TO SET. PARTICULARLY USEFUL CEMENT FROM AN ECONOMIC AND STRUCTURAL POINT OF VIEW HAVE THREE TO TWELEVE TIMES THE VOLUME OF GAS PRESENT. A METHOD FOR THE PRODUCTION OF THESE EXPANDED CEMENTS IS ALSO CLAIMED.
Inventors
- 👤 John Lee Edwards
- 👤 James Macoustra
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:23
CPC Classifications
C; C04; C04B; C04B24/00; C04B24/40; C04B24/42; C04B28/00; C04B28/30; C04B28/32
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) | 1974-04-05 | 1974-10-05 | 1975-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-05 | 1978-10-05 | 1979-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-05 | 1982-10-05 | 1983-04-06 | $7700.00 | Window Closed / Lapsed |