Photocopying – Contact printing – Light boxes
Patent
1990-10-17
1992-04-14
Grimley, A. T.
Photocopying
Contact printing
Light boxes
29132, 118657, 355259, G03G 1509
Patent
active
051052261
ABSTRACT:
A developer carrier in the form of a developing roller constituting a part of one of a plurality of developing units incorporated in a color developing device which is mounted on an electrophotographic image forming apparatus. Latent images electrostatically formed on a photoconductive element included in the image forming apparatus each is developed by a magnet brush formed by the developer of particular color on associated one of the developing rollers. Each developing roller has a non-magnetic conductive base, a first layer formed on the base and having an insulation resistance greater than 10.sup.6 ohms, and a second layer formed on the first layer and having an insulation resistance lying in the range of 10.sup.4 ohms to 10.sup.9 ohms. The developing roller prevents a bias being applied thereto for development from leaking due to scratches or similar defects of the photoconductive element. While the developing device is in operation, a magnet brush is prevented from being formed on the developing rollers of those developing units which are not joining in the development.
REFERENCES:
patent: 4023899 (1977-05-01), Hayashi et al.
patent: 4250605 (1981-02-01), Chapman
patent: 4268943 (1981-05-01), Watanabe et al.
patent: 4292923 (1981-10-01), Huggins
patent: 4422749 (1983-12-01), Hoshino et al.
patent: 4508052 (1985-04-01), Kohyama
patent: 4564285 (1986-01-01), Yasuda et al.
patent: 4760422 (1988-07-01), Seimiya et al.
patent: 4827868 (1989-05-01), Tarumi et al.
Grimley A. T.
Ramirez Nestor R.
Ricoh & Company, Ltd.
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