US2565004A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming oxide coating on tantalum electrodes
Assignee: Electrons Inc
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Filing: 1949-09-10
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Granted: 1951-08-21
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Expires: 1969-09-10
Abstract
No abstract record available.
Inventors
- 👤 Earl K Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:13
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/04; H01J9/042; C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/10
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
95 words
THE METHOD OF FORMING A UNIFORM AND CONSISTENT DENSE COATING OF A DARK COLORED OXIDE ON THE SURFACE OF A TANTALUM ELECTRODE FOR ELECTRON DISCHARGE TUBES, WHICH CONSISTS IN REPEATEDLY HEATING IN A GAS FLAME A PORTION OF A THIN TANTALUM SHEET TO A DULL RED HEAT AND BRIEFLY EXPOSING SUCH HEATED PORTION TO THE ATMOSPHERE AFTER EACH HEATING UNTIL THE VISIBLE COLOR DISAPPEARS, SAID CYCLE OF HEATING AND BRIEF EXPOSURE TO THE ATMOSPHERE BEING REPEATED FOR THE DIFFERENT PORTIONS OF SAID TANTALUM SHEET UNTIL AN OXIDE COATING OF THE DESIRED DENSITY HAS BEEN FORMED.
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) | 1954-08-20 | 1955-02-19 | 1955-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-08-20 | 1959-02-19 | 1959-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-08-20 | 1963-02-19 | 1963-08-21 | $7700.00 | Window Closed / Lapsed |