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US2438488A
Expired / Lapsed
US
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Process of making alumina utilizing kaolin, marl, and related materials
Assignee: MONOLITH PORTLAND MIDWEST Co
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Filing: 1943-06-22
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Granted: 1948-03-30
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Expires: 1963-06-22
Abstract
No abstract record available.
Inventors
- 👤 Frank J Anderson
- 👤 Duncan R Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:06
CPC Classifications
C; C01; C01F; C01F7/00; C01F7/02; C01F7/04; C01F7/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US46979A
Cited
US1320172A
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US941799A
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US1137860A
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US1964685A
Cited
GB499855A
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US2242258A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-03-30 | 1951-09-29 | 1952-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-03-30 | 1955-09-29 | 1956-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-03-30 | 1959-09-29 | 1960-03-30 | $7700.00 | Window Closed / Lapsed |