Patent ID: 8369755

Claim:
A developing device comprising: a developer charging member configured to charge a toner serving as a one-component developer; and a developer hearing member configured to bear and feed the charged toner while forming an electric field so that the toner hops, wherein the developer hearing member includes: an insulating substrate; plural electrodes arranged on the insulating substrate in a developer feeding direction to form the electric field; and an outermost layer covering the plural electrodes, wherein the toner has a softening point of from 115° C. to 130° C.; and wherein the outermost layer includes a polymer including a chemical structural unit having the following formula (1): wherein each of R 1 and R 2 represents a hydrogen atom, an alkyl group, or an aryl group, wherein R 1 and R 2 optionally share bond connectivity to form a cyclic hydrocarbon group having 5 to 8 carbon atoms; each of R 3 and R 4 represents a hydrogen atom, a halogen atom, an alkyl group optionally having a substituent, or an aryl group optionally having a substituent; and a represents a number of the group R 3 connected with a benzene ring, b represents a number of the group R 4 connected with a benzene ring, and each of a and b is an integer of 1 or 2, wherein when a is 2, the two groups R 3 may be the same as or different from each other, and when b is 2, the two groups R 4 may be the same as or different from each other.