US3652307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alumina refractories
Assignee: General Refractories Co
•
Filing: 1969-07-07
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Granted: 1972-03-28
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Expires: 1989-07-07
Abstract
Abstract Disclosed herein is a refractory brick batch mix which consists essentially of, by weight, about 85 to 95 percent alumina, about 2.99 to 12.99 percent silica, about 0.01 to 0.5 percent of a lithium compound capable of oxidizing to lithium oxide, and about 2 to 7 percent volatilized silica. Refractories prepared from these mixtures exhibit increased strength, higher density, lower porosity and higher refractoriness compared to those previously available.
Inventors
- 👤 Wate T Bakker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:56
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
43 words
A refractory brick batch mix according to claim 1 consisting essentially of, by weight, about 88 to 92 percent alumina, about 4.95 to 8.95 percent silica, about 0.05 to 0.2 percent of said lithium compound and about 3 to 5 percent volatilized silica.
Claim 2
Dependent Claim
29 words
A refractory brick batch mix according to claim 1 wherein said alumina contains at least about 99 percent Al2O3 and said silica contains at least about 99 percent SiO2.
Claim 3
Dependent Claim
29 words
A refractory brick batch mix according to claim 3 wherein said alumina is at least about 99.5 percent Al2O3 and said silica is at least about 99.9 percent SiO2.
Claim 4
Dependent Claim
45 words
A refractory brick batch mix according to claim 3 wherein at least about 10 to 35 percent, by weight, of said alumina will be -325 mesh or finer and at least about 50 percent, by weight, of said silica will be -325 mesh or finer.
Claim 5
Dependent Claim
25 words
A refractory brick batch mix according to claim 1 wherein said lithium compound is selected from the group consisting of lithium fluoride and lithium carbonate.
Claim 6
Dependent Claim
16 words
A refractory brick batch mix according to claim 6 wherein said lithium compound is lithium fluoride.
Claim 7
Dependent Claim
26 words
A refractory brick batch mix according to claim 1 wherein there is incorporated a binder selected from the group consisting of phosphoric acid and sodium lignosulfonate.
References Cited (Backward Citations)
US2559343A
Cited
US3067050A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-28 | 1975-09-27 | 1976-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-28 | 1979-09-27 | 1980-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-28 | 1983-09-27 | 1984-03-28 | $7700.00 | Window Closed / Lapsed |