Patent US4087828A successfully refreshed from Google Patents.
US4087828A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the storage and reproduction of information
Assignee: Hoechst AG
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Filing: 1973-02-21
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Granted: 1978-05-02
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Expires: 1993-02-21
Abstract
Abstract A process for patterned storage and reproduction of information in which a photoconductive recording material is altered by an electron beam in correspondence with the information, a free charge is applied to the photoconductive recording material and the flowing off of this charge is made visible differing in correspondence with the pattern.
Inventors
- 👤 Erwin Lind
- 👤 Dieter Messner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:32
CPC Classifications
G; G03; G03G; G03G17/00; G03G5/00; G03G5/02; G11; G11C; G11C13/00; G11C13/04; G11C13/042; G11C13/046; G11C13/048
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
113 words
A process for the storage and reproduction of information in which photoconductive recording material is altered by means of image-wise irradiating the surface of said recording material with an electron beam in correspondence with an information to produce a conductivity pattern and used for the reproduction of the information comprising irradiating uncharged photoconductive recording material in the absence of an electric field with an electron beam, applying to the thus produced conductivity pattern a free charge uniformly over the entire surface of the recording material in the absence of light and treating the surface of the recording material with an electrophotographic toner to make visible the charge pattern formed by said uniform charge.
Claim 2
Dependent Claim
113 words
A process for the storage and reproduction of information in which photoconductive recording material is altered by means of image-wise irradiating the surface of said recording material with an electron beam in correspondence with an information to produce a conductivity pattern and used for the reproduction of the information comprising irradiating uncharged photoconductive recording material in the absence of an electric field with an electron beam, applying to the thus produced conductivity pattern a free charge uniformly over the entire surface of the recording material in the absence of light and treating the surface of the recording material with an electrophotographic toner to make visible the charge pattern formed by said uniform charge.
Claim 3
Dependent Claim
15 words
The process according to claim 1, wherein recording material with an organic photoconductor is used.
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) | 1981-05-01 | 1981-10-31 | 1982-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-01 | 1985-10-31 | 1986-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-01 | 1989-10-31 | 1990-05-02 | $7700.00 | Window Closed / Lapsed |