Patent US2904431A successfully refreshed from Google Patents.
US2904431A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrographotographic charging means
Assignee: RCA Corp
•
Filing: 1954-08-26
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Granted: 1959-09-15
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Expires: 1974-08-26
Abstract
No abstract record available.
Inventors
- 👤 Alexander J Moncrieff-Yeates
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:52
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0208; Y; Y10; Y10S; Y10S101/00; Y10S101/37; Y10S430/00; Y10S430/001; Y10S430/102; Y10T; Y10T29/00; Y10T29/43; Y10T29/435; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49204
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
147 words
A METHOD OF ELECTROSTATIC PRINTING COMPRISING THE STEPS OF COATING THE SURFACE OF A PHOTOCONDUCTIVE INSULATING MATERIAL ON A CONDUCTIVE BACKING MEMBER WITH A THIN FILM OF A LIQUID HAVING A BULK RESISTIVITY OF AT LEAST 10**9 OHM-CENTIMETERS, CLOSELY SPACING AN ELECTRODE WHICH IS CONDUCTIVE IN BULK FROM SAID PHOTOCONDUCTIVE INSULTATING MATERIAL AND IN AREA CONTACT WITH THE SURFACE OF SAID FILM OF LIQUID, ESTABLISHING AN ELECTRIC POTENTIAL BETWEEN SAID ELECTRODE AND SAID BACKING MEMBER OF A MAGNITUDE SUFFICIENT TO PRODUCE AN ELECTROSTATIC CHARGE AT THE SURFACE OF SAID PHOTCONDUCTIVE INSULATING MATERIAL, REMOVING SAID ELECTRODE FROM SAID CLOSELY SPACED RELATIONSHIP, REMOVING THE LIQUID REMAINING ON THE SURFACE OF SAID PHOTOCONDUCTIVE INSULATING MATERIAL, PHOTOGRAAPHICALLY EXPOSING THE SURFACE OF SAID PHOTOCONDUCTIVE INSULATING MATERIAL THEREBY PRODUCING AN ELECTROSTATIC LATENT IMAGE ON THE SURFACE OF SAID PHOTOCONDUCTIVE INSULATING MATERIAL AND THEN DEVELOPING SAID ELECTROSTATIC LATENT IMAGE WITH AN ELECTROSTATICALLY ATTRAACTABLE SUBSTANCE.
Claim 2
Independent Claim
147 words
A METHOD OF ELECTROSTATIC PRINTING COMPRISING THE STEPS OF COATING THE SURFACE OF A PHOTOCONDUCTIVE INSULATING MATERIAL ON A CONDUCTIVE BACKING MEMBER WITH A THIN FILM OF A LIQUID HAVING A BULK RESISTIVITY OF AT LEAST 10**9 OHM-CENTIMETERS, CLOSELY SPACING AN ELECTRODE WHICH IS CONDUCTIVE IN BULK FROM SAID PHOTOCONDUCTIVE INSULTATING MATERIAL AND IN AREA CONTACT WITH THE SURFACE OF SAID FILM OF LIQUID, ESTABLISHING AN ELECTRIC POTENTIAL BETWEEN SAID ELECTRODE AND SAID BACKING MEMBER OF A MAGNITUDE SUFFICIENT TO PRODUCE AN ELECTROSTATIC CHARGE AT THE SURFACE OF SAID PHOTCONDUCTIVE INSULATING MATERIAL, REMOVING SAID ELECTRODE FROM SAID CLOSELY SPACED RELATIONSHIP, REMOVING THE LIQUID REMAINING ON THE SURFACE OF SAID PHOTOCONDUCTIVE INSULATING MATERIAL, PHOTOGRAAPHICALLY EXPOSING THE SURFACE OF SAID PHOTOCONDUCTIVE INSULATING MATERIAL THEREBY PRODUCING AN ELECTROSTATIC LATENT IMAGE ON THE SURFACE OF SAID PHOTOCONDUCTIVE INSULATING MATERIAL AND THEN DEVELOPING SAID ELECTROSTATIC LATENT IMAGE WITH AN ELECTROSTATICALLY ATTRAACTABLE SUBSTANCE.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-09-14 | 1963-03-16 | 1963-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-09-14 | 1967-03-16 | 1967-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-09-14 | 1971-03-16 | 1971-09-15 | $7700.00 | Window Closed / Lapsed |