Patent EP0066141A2 successfully refreshed from Google Patents.
EP0066141A2
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EP
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Electrophotographic recording method
Assignee: Hitachi Ltd
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Filing: 1982-05-13
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Granted: —
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Expires: 2002-05-13
Abstract
Abstract In an electrophotographic recording method in which electric charge is uniformly applied to the surface of a photoconductive drum (1), the drum surface is then exposed to a first information light beam (3A) to form a first negative latent image, the first negative latent image is developed with a first two-component developer (4B), the drum surface is further exposed to a second information light beam (5A) to form a second negative latent image, and the second negative latent image is developed with a second two-component developer (6B) to produce a two-color toner image, the toner content (a 2 ) in the second two-component developer is made larger than that (a,) in the first two-component developer.
Inventors
- 👤 Isamu Komatsu
- 👤 Masayasu Anzai
- 👤 Nobuyoshi Hoshi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 14:04
CPC Classifications
G; G03; G03G; G03G13/00; G03G13/01; G03G13/013
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
133 words
1 . A method for electrophotographically recording a color image by using an electrophotographic recording apparatus comprising a rotatable photoconductive drum (1), means (2) for uniformly charging the surface of the photoconductive drum, first exposure means (3) for exposing the charged photoconductive drum to form a first electrostatic latent image, first developing means (4) containing a first two-component developer (4B) for reversal development of the first electrostatic latent image, second exposure means (5) disposed downstream of the first developing means in the rotational direction of the photoconductive drum, and second developing means (6) containing a second two-component developer (6B) for reversal development of the second electrostatic latent image, wherein the toner-to-carrier ratio (a l ) of said first two-component developer is made smaller than that (a 2 ) of said second two-component developer.
Claim 2
Dependent Claim
133 words
1 . A method for electrophotographically recording a color image by using an electrophotographic recording apparatus comprising a rotatable photoconductive drum (1), means (2) for uniformly charging the surface of the photoconductive drum, first exposure means (3) for exposing the charged photoconductive drum to form a first electrostatic latent image, first developing means (4) containing a first two-component developer (4B) for reversal development of the first electrostatic latent image, second exposure means (5) disposed downstream of the first developing means in the rotational direction of the photoconductive drum, and second developing means (6) containing a second two-component developer (6B) for reversal development of the second electrostatic latent image, wherein the toner-to-carrier ratio (a l ) of said first two-component developer is made smaller than that (a 2 ) of said second two-component developer.
Claim 3
Dependent Claim
45 words
A method according to claim 1 wherein electric charge on the toner of said first developer (4B) is smaller than that on the toner of said second developer (6B) when the toner ratio of said first developer is equal to that of said second developer.
Claim 4
Dependent Claim
69 words
A method according to claim 1 wherein each of said first and second developing means comprises magnetic brush developing means which creates a magnetic brush (4C, 6C) of each of said first and second developers for brushing the surface of said photoconductive drum, and wherein the magnetic brush (6C) of said second developing means is rotated in the same direction as the direction in rotation of said photoconductive drum.
Claim 5
Dependent Claim
36 words
A method according to claim 3 wherein the brushing of said photoconductive drum by the magnetic brush of said second developing means is more weaken than that by the magnetic brush of said first developing means.
Claim 6
Dependent Claim
40 words
A method according to claim 3 or 4 wherein a bias voltage of the same polarity as that of electric charge on the surface of said photoconductive drum is applied to the magnetic brush (6C) of said second developing means.
References Cited (Backward Citations)
No citation records indexed.
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