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US2699404A
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Process for making electrical contact brushes containing calcium carbonate
Assignee: Union Carbide Corp
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Filing: 1952-08-01
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Granted: 1955-01-11
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Expires: 1972-08-01
Abstract
No abstract record available.
Inventors
- 👤 Ramadanoff Dimiter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:32
CPC Classifications
H; H01; H01B; H01B1/00; H01B1/14; H01B1/18
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
87 words
A PROCESS FOR INTRODUCING CALCIUM CARBONATE INTO CONVENTIONAL CARBONACEOUS BRUSH STOCK WHICH COMPRISES PLACING SAID BRUSH STOCK UNDER A PRESSURE LESS THAN ATMOSPHERIC, IMMERSING SAID BRUSH STOCK IN AN AQUEOUS SOLUTION OF CALCIUM NITRATE WHILE SAID BRUSH STOCK IS UNDER SAID SUB-ATMOSPHERIC PRESSURE, SUBJECTING SAID BRUSH STOCK WHILE IT IS IMMERSED IN SAID SOLUTION TO AT LEAST ATMOSPHERIC PRESSURE, DRYING SAID BRUSH STOCK, AND HEATING SAID BRUSH STOCK TO A TEMPERATURE OF ABOUT 650* C. TO CONVERT THE CALCIUM NITRATE IN SAID BRUSH STOCK TO CALCIUM CARBONATE.
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) | 1958-01-10 | 1958-07-12 | 1959-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-01-10 | 1962-07-12 | 1963-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-01-10 | 1966-07-12 | 1967-01-11 | $7700.00 | Window Closed / Lapsed |