US3772010A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic apparatus and method for imagewise charge generation and transfer
Assignee: Eastman Kodak Co
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Filing: 1972-03-03
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Granted: 1973-11-13
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Expires: 1992-03-03
Abstract
Abstract An electrophotographic apparatus and method for image-wise generating electrostatic charges from a unique electrophotographic recording element and for simultaneously imagewise transferring such charges to a insulative receiving sheet to form a developable latent electrostatic image thereon. The recording element comprises a layer of radiation-responsive material, such as a photoconductor, which is disposed between a conductive backing and a fine conductive grid member, the latter being separated from the radiation-responsive layer by a small air-gap. Imagewise charge generation is accomplished by imagewise exposing the radiation-responsive layer of the recording element to actinic radiation while creating a sufficient electric field between the conductive backing of the recording element and the grid member to produce an ionic or corona discharge between the irradiated portions of the radiation-responsive layer and the grid member. Simultaneous imagewise charge transfer is accomplished by spacedly arranging the insulative receiving sheet relative to the grid member of the recording element and creating a second electric field between the grid member and an electrode disposed behind the receiving sheet, whereby charges generated during exposure of the electrographic plate are immediately drawn to the insulative receiving sheet.
Inventors
- 👤 A Weiss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:24
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/05
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
31 words
The invention according to claim 1 wherein said first electrical field is an AC field, whereby both positive and negative charges are imagewise generated during imagewise exposure of said radiation-responsive layer.
Claim 2
Dependent Claim
14 words
The invention according to claim 1 wherein said radiation-responsive layer comprises a photoconductive material.
Claim 3
Dependent Claim
14 words
The invention according to claim 1 wherein sAid radiation-responsive layer comprises a heat-deformable material.
Claim 4
Dependent Claim
48 words
The invention according to claim 1 wherein said radiation-responsive layer comprises contiguous first and second sublayers, said first sublayer comprising a photoconductive material, and said second sublayer comprises a phosphor-containing material which, when imagewise exposed to x-radiation, fluoresces and thereby selectively increases the conductivity of said first sublayer.
Claim 5
Dependent Claim
167 words
A process for imagewise generating charges in an electrophotographic recording element and for substantially simultaneously imagewise transferring such charges to a dielectric receiving sheet disposed on a conductive support, such recording element comprising a radiation-responsive layer having an electrically conductive backing, an electrically conductive grid member, and means defining a substantially uniform air-gap having an average width of between approximately 1.0 and 1,000 microns between said layer and grid member, said process comprising the steps of a. spacedly arranging said receiving sheet relative to said grid member; b. electrically biasing said grid member relative to said conductive backing while simultaneously imagewise exposing said radiation-responsive layer to actinic radiation to imagewise vary the threshold potential required for corona emission between said radiation-responsive layer and said grid member, and to produce imagewise charge generation between said layer and said grid member; and c. electrically biasing said conductive support relative to said grid member to imagewise attract charges generated during imagewise exposure of said radiation-responsive layer to said receiving sheet.
Claim 6
Dependent Claim
50 words
The invention according to claim 6 wherein electrical biasing of said grid member relative to said conductive backing is achieved by applying an AC source of potential between said grid member and said conductive backing, whereby both positive and negative charges are generated during image-wise exposure of said radiation-responsive layer.
Claim 7
Dependent Claim
25 words
The invention according to claim 6 wherein said receiving sheet is spaced from said grid member an average distance of from 1.0 to 10.0 millimeters.
Claim 8
Dependent Claim
14 words
The invention according to claim 6 wherein said radiation-responsive layer comprises a photoconductive compound.
Claim 9
Dependent Claim
14 words
The invention according to claim 6 wherein said radiation-responsive layer comprises a heat-deformable material.
Claim 10
Dependent Claim
31 words
The invention according to claim 6 wherein said radiation-responsive layer comprises contiguous first and second sublayers, said first sublayer comprising a photo-conductive material, and said second sublayer comprises a phosphor-containing material.
Claim 11
Dependent Claim
156 words
An electrophotographic process comprising the steps of a. spacedly arranging a dielectric receiving sheet relative to an electrophotographic recording element, such element comprising a photoconductive insulating layer having a conductive backing disposed on one surface thereof and an electrically conductive grid member between 1.0 and 1,000 microns from and extending substantially parallel to the other surface of said layer, said receiving sheet being arranged so as to face said grid member and be spaced therefrom an average distance of from 1.0 to 10.0 millimeters; b. applying an electrical potential between said grid member and said conductive backing while simultaneously imagewise exposing said photoconductive layer to actinic radiation to selectively increase the conductivity of said layer and produce imagewise charge generation between said layer and said grid member; and c. establishing an electric field between said grid member and said receiving sheet to imagewise attract charges generated during exposure of said photoconductive layer to said receiving sheet.
Claim 12
Dependent Claim
25 words
The invention according to claim 12, further comprising the step of selectively depositing toner particles on said receiving sheet to render the charge thereon visible.
Claim 13
Dependent Claim
19 words
The invention according to claim 13, further comprising the step of fusing the toner particles to said receiving sheet.
Claim 14
Independent Claim
163 words
A method for forming an electrostatic charge pattern on an electrically insulative surface, said method comprising the steps of: positioning an insulative surface apart from and parallel to a photoconductive insulating layer; interposing a conductive grid between said surface and said layer, so as to be spaced from and extend substantially parallel to both said insulative surface and said layer, the spacing between said grid and said layer being between 1.0 and 1,000 microns; establishing a first electric field in the space between said grid and said layer, such first electric field being of an intensity less than the threshold level required for ionic movement between said grid and said layer when said layer is unexposed to activating radiation; simultaneously exposing said layer to a pattern of activating radiation to produce selective ionic movement between said grid and said layer; and simultaneously applying a second electric field in the space between said surface and said grid to imagewise attract ions to said surface.
References Cited (Backward Citations)
US2825814A
Cited
US2758525A
Cited
US3066298A
Cited
US3071645A
Cited
US3185051A
Cited
US3458700A
Cited
US3329500A
Cited
US3464818A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |