Abstract A method for charging an electrophotographic member comprising a photoconductive insulating layer, an insulating substrate, and a conductive layer interposed between the photoconductive insulating layer and the insulating substrate, the conductive layer being unconnected to any source of reference electric potential, the method comprising the steps of relatively moving the electrophotographic member and two corona discharge electrodes, the first of which precedes the second, exposing the photoconductive insulating layer of the electrophotographic member to the first corona discharge electrode, the polarity of which is opposite to that of the majority carriers of the photoconductive insulating layer and subsequently exposing the photoconductive insulating layer of the electrophotographic member to the second corona discharge, the polarity of which is the same as that of the majority carriers whereby the electrophotographic member is readily charged even though the conductive layer is unconnected to a source of reference electric potential.
A method as in claim 1 where said photoconductive insulating layer is N-type and the polarities of said two corona discharge electrodes are respectively positive and negative.
Claim 2
Dependent Claim
27 words
A method as in claim 1 where said photoconductive insulating layer is P-type and the polarities of said two corona discharge electrodes are respectively negative and positive.
Claim 3
Independent Claim
146 words
A method for charging an electrophotographic member comprising a photoconductive insulating layer, an insulating substrate, and a conductive layer interposed between said photoconductive insulating layer and said insulating substrate, said conductive layer being unconnected to any source of reference electric potential, said method comprising the steps of: relatively moving said electrophotographic member and two corona discharge electrodes, the first of which precedes the second; exposing the photoconductive insulating layer of said electrophotographic member to said first corona discharge electrode, the polarity of which is opposite to that of the majority carriers of said photoconductive insulating layer; and subsequently exposing the photoconductive insulating layer of said electrophotographic member to said second corona discharge, the polarity of which is the same as that of said majority carriers whereby said electrophotographic member is readily charged even though said conductive layer is unconnected to a source of reference electric potential.
Claim 4
Dependent Claim
29 words
A method as in claim 4 wherein said photoconductive insulating layer is N-type and the polarities of said first and second corona discharge electrodes are respectively positive and negative.
Claim 5
Dependent Claim
29 words
A method as in claim 4 where said photoconductive insulating layer is P-type and the polarities of said first and second corona discharge electrodes are respectively negative and positive.
Claim 6
Dependent Claim
15 words
A method as in claim 4 where said source of reference electric potential is ground.