Patent US3578446A successfully refreshed from Google Patents.
US3578446A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic reproduction employing bi-charging and negative-charging zinc oxide
Assignee: Bridgestone Firestone Inc
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Filing: 1967-07-26
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Granted: 1971-05-11
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Expires: 1987-07-26
Abstract
Abstract DIRECT ELECTROSTATIC DUPLICATION PROCESSES ARE OFTEN PLAGUED WITH PROBLEMS OF BACKGROUND PRINTING. THE INCLUSION OF BI-CHARGING ZINC OXIDE, AND/OR OF POLYVINYL ALCHOHOL IN THE COATING COMPOSITION APPLIED TO THE PAPER OR OTHER SUBSTRATE WILL GREATLY REDUCE THIS PROBLEM.
Inventors
- 👤 Meyer L Sugarman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:21
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/08; G03G5/087
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-10 | 1974-11-09 | 1975-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-10 | 1978-11-09 | 1979-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-10 | 1982-11-09 | 1983-05-11 | $7700.00 | Window Closed / Lapsed |