US2919994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fused cast refractory
Assignee: Walsh Refractories Corp
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Filing: 1957-10-30
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Granted: 1960-01-05
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Expires: 1977-10-30
Abstract
No abstract record available.
Inventors
- 👤 Jr Frank C Steimke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:23
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/48; C04B35/484
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
91 words
A HEAT CAST REFRACTORY CONSISTING ESSENTIALLY OF ZIRCONIA, ALUMINA, AND SILICA, BONDED WITH A BOROSILICATE GLASS IN WHICH THE SILICA IN SAID REFRACTORY IN BETWEEN 12% AND 22% BY WEIGHT, THE ZIRCONIA BETWEEN 25% AND 45% BY WEIGHT, AND THE ALUMINA BETWEEN 40% AND 60% BY WEIGHT, SAID REFRACTORY HAVING BETWEEN ABOUT 1/2 AND 1% BY WEIGHT OF BORIC OXIDE AND AT LEAST ONE OF THE ALKALIES SELECTED FROM THE GROUP CONSISTING OF NA2O, K2O, AND LI2O NOT OVER 1% BY WEIGHT AND BEING SUBSTANTIALLY FREE FROM TITANIA AND IRON OXIDE.
Claim 2
Dependent Claim
91 words
A HEAT CAST REFRACTORY CONSISTING ESSENTIALLY OF ZIRCONIA, ALUMINA, AND SILICA, BONDED WITH A BOROSILICATE GLASS IN WHICH THE SILICA IN SAID REFRACTORY IN BETWEEN 12% AND 22% BY WEIGHT, THE ZIRCONIA BETWEEN 25% AND 45% BY WEIGHT, AND THE ALUMINA BETWEEN 40% AND 60% BY WEIGHT, SAID REFRACTORY HAVING BETWEEN ABOUT 1/2 AND 1% BY WEIGHT OF BORIC OXIDE AND AT LEAST ONE OF THE ALKALIES SELECTED FROM THE GROUP CONSISTING OF NA2O, K2O, AND LI2O NOT OVER 1% BY WEIGHT AND BEING SUBSTANTIALLY FREE FROM TITANIA AND IRON OXIDE.
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) | 1963-01-04 | 1963-07-06 | 1964-01-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-04 | 1967-07-06 | 1968-01-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-04 | 1971-07-06 | 1972-01-05 | $7700.00 | Window Closed / Lapsed |