US3773507A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic reversal development process employing a pre-toner
Assignee: Fujifilm Holdings Corp
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Filing: 1971-07-02
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Granted: 1973-11-20
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Expires: 1991-07-02
Abstract
Abstract A reversal development process which comprises, after uniformly charging a photoconductive insulating coating with a charge of one polarity, applying a finely divided pre-toner having a white or off-white appearance and a charge of the same polarity as that of the uniform charge whereby the pre-toner deposits at the charge-deficient areas in the coating, then subjecting the thus treated coating to image exposure to form an electro-static latent image, and finally developing the latent image by applying a finely divided toner differently colored from the pre-toner, the toner having a charge of the same polarity as that of the latent image.
Inventors
- 👤 M Sato
- 👤 O Fukushima
- 👤 S Honjo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:31
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G13/00; G03G13/22
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
18 words
A reversal development process as in claim 1 where said photoconductive pre-toner has a white or off-white appearance.
References Cited (Backward Citations)
US3512965A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |