US3241989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alumina refractories
Assignee: Harbison Walker Refractories Co
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Filing: 1965-07-09
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Granted: 1966-03-22
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Expires: 1985-07-09
Abstract
No abstract record available.
Inventors
- 👤 Berhl E Wishon
- 👤 Donald F Stock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:28
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/16; C04B35/18; C04B33/00; C04B33/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
93 words
A FIRED, HIGH ALUMINA REFRACTORY SHAPE, MADE FROM A SIZE GRADED REFRACTORY BATCH CONSISTING ESSENTIALLY OF, BY WEIGHT, 50 TO 90% CALCINED BAUXITIC KAOLIN, THE REMAINDER BEING SELECTED MATERIAL OF THE GROUP CONSISTING ESSENTIALLY OF FINELY DIVIDED CALCINED AND CRUDE ALUMINUM ORES, FINELY DIVIDED CALCINED AND CRUDE KAOLIN, AND FINELY DIVIDED BALL CLAY, THE SELECTED MATERIAL SUBSTANTIALLY ALL PASSING A 100 MESH SCREEN, THERE BEING NO MORE THAN ABOUT 1%, BY WEIGHT, ALKALIES IN THE BATCH, SAID SHAPE BEING SUBSTANTIALLY FREE OF VITRIFICATION, BEING MICROSCOPICALLY CRYSTALLINE, AND CHARACTERIZED BY SUBSTANTIALLY TRUE MINERAL HOMOGENEITY.
Claim 2
Dependent Claim
93 words
A FIRED, HIGH ALUMINA REFRACTORY SHAPE, MADE FROM A SIZE GRADED REFRACTORY BATCH CONSISTING ESSENTIALLY OF, BY WEIGHT, 50 TO 90% CALCINED BAUXITIC KAOLIN, THE REMAINDER BEING SELECTED MATERIAL OF THE GROUP CONSISTING ESSENTIALLY OF FINELY DIVIDED CALCINED AND CRUDE ALUMINUM ORES, FINELY DIVIDED CALCINED AND CRUDE KAOLIN, AND FINELY DIVIDED BALL CLAY, THE SELECTED MATERIAL SUBSTANTIALLY ALL PASSING A 100 MESH SCREEN, THERE BEING NO MORE THAN ABOUT 1%, BY WEIGHT, ALKALIES IN THE BATCH, SAID SHAPE BEING SUBSTANTIALLY FREE OF VITRIFICATION, BEING MICROSCOPICALLY CRYSTALLINE, AND CHARACTERIZED BY SUBSTANTIALLY TRUE MINERAL HOMOGENEITY.
References Cited (Backward Citations)
US1802298A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-03-21 | 1969-09-20 | 1970-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-03-21 | 1973-09-20 | 1974-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-03-21 | 1977-09-20 | 1978-03-22 | $7700.00 | Window Closed / Lapsed |