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US4087828A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the storage and reproduction of information

Assignee: Hoechst AG
•
Filing: 1973-02-21
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Granted: 1978-05-02
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Expires: 1993-02-21
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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 19:04
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)

US2845348A Cited
US3653064A Cited
US3673595A Cited

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

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