US2978607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic writing tube
Assignee: AB Dick Co
•
Filing: 1958-02-07
•
Granted: 1961-04-04
•
Expires: 1978-02-07
Abstract
No abstract record available.
Inventors
- 👤 Howard C Borden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:50
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/02; H01J31/06; H01J31/065
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1964-04-03 | 1964-10-03 | 1965-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-03 | 1968-10-03 | 1969-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-03 | 1972-10-03 | 1973-04-04 | $7700.00 | Window Closed / Lapsed |