US2597511A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selectively demetalizing condenser paper
Assignee: National Research Corp
•
Filing: 1949-10-01
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Granted: 1952-05-20
•
Expires: 1969-10-01
Abstract
No abstract record available.
Inventors
- 👤 Glenn L Mellen
- 👤 Jr Vincent C Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:31
CPC Classifications
H; H01; H01G; H01G13/00; H01G13/06; Y; Y10; Y10T; Y10T29/00; Y10T29/43; Y10T29/435; Y10T83/00; Y10T83/283
Claims Analysis
Total Claims: 0
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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) | 1955-05-20 | 1955-11-19 | 1956-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-05-20 | 1959-11-19 | 1960-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-05-20 | 1963-11-19 | 1964-05-20 | $7700.00 | Window Closed / Lapsed |