Patent US4063945A successfully refreshed from Google Patents.
US4063945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatographic imaging method
Assignee: Xerox Corp
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Filing: 1977-02-17
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Granted: 1977-12-20
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Expires: 1997-02-17
Abstract
Abstract Disclosed is a method for forming a latent electrostatic image on a photosensitive device comprising a grounded conductive substrate having on its surface a layer of photoconductive material which is in turn overcoated with a layer of insulating organic resin. The method involves applying an initial electrostatic charge of one polarity to the surface of the photosensitive device followed by the steps of: 1. applying to the surface of the photosensitive device an electronic field of direct current having a polarity opposite to that of the initial electrostatic charge, and, either simultaneously or sequentially, exposing the device to imagewise activating radiation; 2. uniformly exposing the device to activating radiation; and 3. applying an electrostatic charge of the same polarity as that of the initial charge to the surface of the photosensitive device to thereby simultaneously erase the electrostatic charge from the device and initially charge it as the first step in the next cycle.
Inventors
- 👤 Donald C. Von Hoene
- 👤 Richard L. Post
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:58
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/226; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/102
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
225 words
A method of forming a latent electrostatic image on a photosensitive device comprising a grounded conductive substrate having on its surface a layer of photoconductive material which is in turn overcoated with a layer of electrically insulating organic resin which method comprises applying an initial electrostatic charge of one polarity to the surface of the photosensitive device to provide an initial potential which is solely across the insulating layer followed by the steps of: a. applying to the surface of the photosensitive device an electronic field of direct current having a polarity opposite to that of the initial electrostatic charge to drive the initial potential to a potential included in the range extending from a potential less than the initial potential through zero to a chosen potential opposite in sign to the polarity of the initial potential and, either simultaneously or sequentially, exposing the photosensitive device to imagewise activating radiation thereby forming a imagewise potential distribution across the layer of photoconductive material; b. forming an imagewise potential distribution across the insulating layer by uniformly exposing the device to activating radiation; and c. applying an electrostatic charge of the same polarity as that of the initial charge to the surface of the photosensitive device to thereby simultaneously erase the electrostatic charge from the device and initially charge it as the first step in the next cycle.
Claim 2
Independent Claim
225 words
A method of forming a latent electrostatic image on a photosensitive device comprising a grounded conductive substrate having on its surface a layer of photoconductive material which is in turn overcoated with a layer of electrically insulating organic resin which method comprises applying an initial electrostatic charge of one polarity to the surface of the photosensitive device to provide an initial potential which is solely across the insulating layer followed by the steps of: a. applying to the surface of the photosensitive device an electronic field of direct current having a polarity opposite to that of the initial electrostatic charge to drive the initial potential to a potential included in the range extending from a potential less than the initial potential through zero to a chosen potential opposite in sign to the polarity of the initial potential and, either simultaneously or sequentially, exposing the photosensitive device to imagewise activating radiation thereby forming a imagewise potential distribution across the layer of photoconductive material; b. forming an imagewise potential distribution across the insulating layer by uniformly exposing the device to activating radiation; and c. applying an electrostatic charge of the same polarity as that of the initial charge to the surface of the photosensitive device to thereby simultaneously erase the electrostatic charge from the device and initially charge it as the first step in the next cycle.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein after the completion of step (c) in the initial cycle, additional cycles consisting of steps (a), (b) and (c) are carried out.
Claim 4
Dependent Claim
26 words
The method of claim 1 wherein the photoconductive material is CdS, CdSe, CdS x Se 1-x , ZnO, TiO 2 , selenium or a selenium alloy.
Claim 5
Dependent Claim
13 words
The method of claim 3 wherein the selenium alloy is Se/Te or Se/As.
Claim 6
Dependent Claim
16 words
The method of claim 1 wherein the photoconductive material is dispersed in an insulating resin binder.
Claim 7
Dependent Claim
32 words
The method of claim 1 wherein the insulating resin is polystyrene, a butadiene polymer, an acrylic or methacrylic polymer, a vinyl resin, an alkyd resin, a polycarbonate resin or a polyester resin.
Claim 8
Dependent Claim
37 words
The method of claim 1 wherein the conductive substrate is aluminum, the photoconductive material is a binder layer of CdS o .35 Se 0 .65 dispersed in a polyester and the insulating organic resin is Mylar polyester.
Claim 9
Dependent Claim
25 words
The method of claim 7 wherein the initial potential is positive and the secondary charging in step (a) drives the initial potential to near zero.
Claim 10
Dependent Claim
35 words
The method of claim 1 wherein the conductive substrate is aluminum having a graphite layer on its surface, the photoconductive material is CdS dispersed in a polyester and the insulating organic resin is Mylar polyester.
Claim 11
Dependent Claim
26 words
The method of claim 1 wherein the initial charge is positive and the secondary charging in step (a) drives the initial potential to a negative potential.
References Cited (Backward Citations)
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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) | 1980-12-19 | 1981-06-20 | 1981-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-19 | 1985-06-20 | 1985-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-19 | 1989-06-20 | 1989-12-20 | $7700.00 | Window Closed / Lapsed |