3909258 is referenced by 108 patents and cites 9 patents.

An electrographic process involving the development of electrical potential patterns on a recording medium surface, for example electrostatic charge patterns on a photoconductive element, with electronically conductive, magnetically attractable toner material utilizing electrical forces generated by the electrical potential in the image areas of the recording medium to overcome a threshold magnetic counterforce exerted on the toner material by means of an electrical potential biased toner material applicator. The electrical potential pattern may be supplemented by a corresponding electronic conductivity pattern on the recording medium surface.

Electrographic development process
Application Number
Publication Number
Application Date
January 2, 1974
Publication Date
September 30, 1975
Kotz Arthur R
Alexander Sell Steldt & Delahunt
Minnesota Mining and Manufacturing Company
G03g 13/22
G03g 13/08
G03G 15/09
G03G 13/09
G03G 13/06
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