Patent ID: 7813662

Claim:
An image forming apparatus, comprising: a plurality of image forming units comprising corresponding image carriers and charging units, the image forming units configured to form toner images of different colors on the corresponding image carriers; a plurality of transfer units disposed to face the corresponding image carriers to form transfer areas between the transfer units and the image carriers and configured to press a transfer member, passing through the transfer areas, to the corresponding image carriers to transfer the toner images, formed on the corresponding image carriers, onto the transfer member at the transfer areas; wherein the charging units include at least one charging member of corona charging type and at least one charging member of contact charging type, and wherein the image forming apparatus sets a first transfer condition for the transfer unit(s) corresponding to the image carrier(s) charged by the at least one charging member of corona charging type and a second, separate transfer condition for the transfer unit(s) corresponding to the image carrier(s) charged by the at least one charging member of contact charging type.