Patent US3569803A successfully refreshed from Google Patents.
US3569803A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic process utilizing friction charging
Assignee: Fujifilm Holdings Corp
•
Filing: 1968-08-14
•
Granted: 1971-03-09
•
Expires: 1988-08-14
Abstract
Abstract A method for electrostatically charging the surface of a photoconductive insulative layer which is formed by dispersing an inorganic n-type photoconductive powder in a binder, which is primarily a vinyl chloride-vinyl acetate copolymer, which comprises rubbing the insulative layer with a friction material so as to produce a negative charge on the surface of the insulative layer. Representative photoconductors, such as ZnO, and friction materials, such as a cotton velvet cloth, are set out in the specification. A modification of the process entails producing the friction by rubbing the insulative layer while a highly insulative liquid is maintained on its surface.
Inventors
- 👤 Masamichi Sato
- 👤 Satoru Honjo
- 👤 Masaaki Takimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:45
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/05; G03G5/0528; G03G5/0532; G03G5/0542; G03G13/00; G03G13/02; G03G13/025; G03G5/0539; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/102
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
42 words
The electrophotographic method of claim 1 wherein said n-type photoconductive material is selected from the group consisting of titanium dioxide, zinc oxide, cadmium sulfide, a mixture of cadmium sulfide and cadmium carbonate, and a mixed crystal of cadmium sulfide and zinc sulfide.
Claim 2
Dependent Claim
28 words
The electrophotographic method of claim 1 wherein said friction material is selected from the group son consisting of cotton velvet, rayon, wool, a tanned leather, nylon, and polyurethane.
Claim 3
Dependent Claim
38 words
The electrophotographic method of claim 1 wherein said surface of a photoconductive insulating layer is subjected to a frictional charging in the liquid after the image-exposure carried out in a substantially noncharged and dark-adapted condition of the layer.
Claim 4
Dependent Claim
38 words
The electrophotographic method of claim 1 wherein the liquid-developing agent to be employed in the subsequent developing process is one to be mixed with the liquid which is applied at the time of the generation of the friction.
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) | 1974-03-08 | 1974-09-07 | 1975-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-08 | 1978-09-07 | 1979-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-08 | 1982-09-07 | 1983-03-09 | $7700.00 | Window Closed / Lapsed |