US3770429A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for removing corona discharge contaminants in electrophotography
Assignee: Katsuragawa Electric Co Ltd
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Filing: 1971-09-13
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Granted: 1973-11-06
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Expires: 1991-09-13
Abstract
Abstract In a method and apparatus for electrophotography in which use is made of photosensitive element including a photoconductive layer and an image forming surface which may be the surface of the photoconductive layer or the surface of a highly insulative layer integrally bonded to the surface of the photoconductive layer and wherein an electric charge is deposited on the image forming surface by means of corona discharge, a light image is projected upon the photosensitive element to form a latent image on the image forming surface, and the latent image is transfer printed onto a recording medium, means is provided to apply an organic solvent to the image forming surface to remove contaminants formed by the ionization of air by the corona discharge.
Inventors
- 👤 K Kinoshita
- 👤 S Uehara
- 👤 H Nagame
- 👤 K Yamada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:09
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/005; G03G15/00; G03G15/14; G03G21/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
192 words
In a method of electrophotography wherein a latent image is formed by the steps of applying a first electric field by means of corona discharge across a photosensitive element including a highly insulative layer and a photoconductive layer exhibiting persistent internal polarization and integrally bonded to said highly insulative layer so as to deposit a charge of one polarity on the surface of said highly insulative layer, applying a second electric field by means of corona discharge across said photosensitive element to deposit a charge of the opposite polarity on the surface of said highly insulative layer, and projecting a light image onto said photoconductive layer concurrently with the application of said second electric field thus forming a latent image corresponding to said light image on the surface of said highly insulative layer, and said latent image is transfer printed onto a recording medium, the improvement which comprises applying an electrically insulative organic solvent onto the image forming surface of said highly insulative layer after said latent image has been transfer printed to remove contaminants formed by the ionization of air by said corona discharge and deposited on said image forming surface.
Claim 2
Dependent Claim
23 words
The method according to claim 2 wherein said solvent is applied by means of a roller in contact with said image forming surface.
Claim 3
Dependent Claim
14 words
The method of electrophotography according to claim 1 wherein said contaminants comprise nitric acids.
Claim 4
Dependent Claim
14 words
The method of electrophotography according to claim 2 wherein said contaminants comprise nitric acids.
Claim 5
Dependent Claim
37 words
The method of electrophotography according to claim 1 in which a thin film of a highly insulative material resistant to said solvent is applied upon said image forming surface prior to formation of a latent image thereon.
Claim 6
Dependent Claim
43 words
The method of electrophotography according to claim 6 wherein said thin film is formed by polymerizing vapor of a styrene monomer by the action of a high frequency electric field and causing a resulting styrene polymer to deposit on said image forming surface.
Claim 7
Dependent Claim
37 words
The method of electrophotography according to claim 2 in which a thin film of a highly insulative material resistant to said solvent is applied upon said highly insulative layer prior to formation of a latent image thereon.
Claim 8
Dependent Claim
43 words
The method of electrophotography according to claim 8 wherein said thin film is formed by polymerizing vapor of a styrene monomer by the action of a high frequency electric field and causing a resulting styrene polymer to deposit on said highly insulative layer.
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) | 1976-11-05 | 1977-05-07 | 1977-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-05 | 1981-05-07 | 1981-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-05 | 1985-05-07 | 1985-11-06 | $7700.00 | Window Closed / Lapsed |