A developer roller which is semiconductive comprising {TAIL ~ a rubber body} containing soyadimethylethyl ammonium ethosulfate in an amount of between 0.5 phr to 4.0 phr by weight of said rubber, blended therein to increase {HEAD ~ conductivity} of said body 
A developer roller which is semiconductive comprising { TAIL ~ a rubber body } containing soyadimethylethyl ammonium ethosulfate in an amount of between 0.5 phr to 4.0 phr by weight of said rubber , blended therein to increase { HEAD ~ conductivity } of said body
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH