Non-magnetic one-component developer and image forming process

摘要

A negatively electrifiable, non-magnetic and single component developer comprising a binder resin, a carbon black and a charge control agent, wherein the carbon black has an average primary particle diameter of 20 to 50 nm and a pH of 2 to 5, and the charge control agent comprises a compound represented by the following formula: <IMAGE> wherein M represents a metal atom selected from the group consisting of zinc, iron, nickel and cobalt, and R1 and R2 each represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. An image forming process using the developer is also disclosed. This one-component developer, which is suitable for use as a black toner in color image formation, can be stably charged and transported over long to give images free from fogging and having evenness of density and hardly poses problems such as dirts and color mixing over long.