Electrophotographic process using corona discharge current of an asymmetrical wave form
Abstract
Abstract An electrophotographic process comprising the steps of (a) applying a first charge by means of direct current corona discharge to an overcoated photosensitive sheet consisting of a conductive base, a photoconductive layer and a surface insulating layer; (b) applying a second charge to the so charged sensitive sheet by means of a corona discharge current of asymmetrical wave form in which the discharge current of a polarity opposite that of the first charge is greater than that of the same polarity and the degree of asymmetry is sufficient to satisfy the specified requirements, and simultaneously exposing the sensitive sheet through or original having an image pattern of light and shadow: and (c) thereafter exposing the photosensitive sheet to an uniform illumination over the entire surface to form a latent electrostatic image of the light area and a latent electrostatic image of the dark area, which are of opposite polarity to each other.
Inventors
- 👤 S Matsumoto
- 👤 N Yonaha
- 👤 T Aizawa
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
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