DEVELOPER AND IMAGE FORMING METHOD

PROBLEM TO BE SOLVED: To provide a developer capable of effectively retaining triboelectric charging property thereof while effectively suppressing deposition of resin fine particles on a photoreceptor, even when long-time continuous low-density printing is carried out, and an image forming method using the same. SOLUTION: The developer includes toner particles, resin fine particles as an external additive, and first and second silica fine particles as external additives. The image forming method using the same is also provided. In the developer, when the number average primary particle diameter of the first silica fine particles is represented by Ad (nm); the coating rate of the first silica fine particles on the toner particles by Ac (%); the number average primary particle diameter of the second silica fine particles by Bd (nm); the coating rate of the second silica fine particles on the toner particles by Bc (%); the number average primary particle diameter of the resin fine particles by Cd (nm); and the coating rate of the resin fine particles on the toner particles by Cc (%), the Ad, Ac, Bd, Bc, Cd and Cc satisfy the following relational expressions (1): 16≤Ad≤35 nm, or the like. COPYRIGHT: (C)2010,JPO&INPIT