Patent US2358018A successfully refreshed from Google Patents.
US2845348A
Expired / Lapsed
US
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Electro-photographic means and method
Assignee: Individual
•
Filing: 1952-01-04
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Granted: 1958-07-29
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Expires: 1972-01-04
Abstract
No abstract record available.
Inventors
- 👤 Kallman Hartmut
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:27
CPC Classifications
G; G03; G03G; G03G13/00; G03G13/22; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/102
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
102 words
A METHOD OF PRACTICING ELECTRO-PHOTOGRAPHY COMPRISING PREPARING AN UNCHARGED THIN LAYER CONTAINING A PHOTO CONDUCTIVE PHOSPHOR, EXPOSING SAID LAYER TO A PATTERN OF LIGHT TO BE REPRODUCED THEREBY TO PRODUCE A LATENT IMAGE OF CONDUCTIVITY IN SAID LAYER, THEN ELECTRICALLY CHARGING SAID LAYER IN DARKNESS AFTER SAID EXPOSURE, DEVELOPING SAID IMAGE IN DARKNESS BY PRESENTING SAID LAYER CLOSELY ADJACENT TO A QUANTITY OF FREELY DISPLACEABLE FINE PARTICLES CAPABLE OF ATTRACTION TO SAID CHARGED LAYER IN AN AMOUNT SELECTIVELY PROPORTIONAL TO THE ENERGY IN THE VARIOUS AREAS OF THE PATTERN AND FIXING THE PARTICLES IN THEIR RESPECTIVE POSITIONS TO PRODUCE A PERMANENT PRINT.
Claim 2
Independent Claim
102 words
A METHOD OF PRACTICING ELECTRO-PHOTOGRAPHY COMPRISING PREPARING AN UNCHARGED THIN LAYER CONTAINING A PHOTO CONDUCTIVE PHOSPHOR, EXPOSING SAID LAYER TO A PATTERN OF LIGHT TO BE REPRODUCED THEREBY TO PRODUCE A LATENT IMAGE OF CONDUCTIVITY IN SAID LAYER, THEN ELECTRICALLY CHARGING SAID LAYER IN DARKNESS AFTER SAID EXPOSURE, DEVELOPING SAID IMAGE IN DARKNESS BY PRESENTING SAID LAYER CLOSELY ADJACENT TO A QUANTITY OF FREELY DISPLACEABLE FINE PARTICLES CAPABLE OF ATTRACTION TO SAID CHARGED LAYER IN AN AMOUNT SELECTIVELY PROPORTIONAL TO THE ENERGY IN THE VARIOUS AREAS OF THE PATTERN AND FIXING THE PARTICLES IN THEIR RESPECTIVE POSITIONS TO PRODUCE A PERMANENT PRINT.
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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) | 1961-07-28 | 1962-01-27 | 1962-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-07-28 | 1966-01-27 | 1966-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-07-28 | 1970-01-27 | 1970-07-29 | $7700.00 | Window Closed / Lapsed |