An electrostatic charge image developing toner includes a plurality of toner particles. Each of the plurality of toner particles includes a toner core and a shell layer covering the toner core. The shell layer contains a thermosetting resin. A content ratio of a toner component insoluble in tetrahydrofuran is at least 90 mass % relative to mass of the toner. Melt viscosity of the toner at 75 C. is at least 1.010.sup.4 Pa.Math.s and no greater than 1.010.sup.5 Pa.Math.s. The thermosetting resin is preferably a melamine resin or a urea resin. The toner core preferably contains a binder resin, and the binder resin has a softening point (Tm) of at least 85 C. and no greater than 95 C.

A low energy consumption monochrome particle includes a core latex having a core a glass transition temperature and a weight average molecular weight. A shell encapsulates the core and includes a shell latex having a shell glass transition temperature and a weight average molecular weight. The glass transition temperature of the shell latex is higher than the glass transition temperature of the core latex. The weight average molecular weight of the shell latex is lower or higher than the weight average molecular weight of the core latex. The low energy consumption monochrome particles are suitable for high speed printing in SCD systems while decreasing minimum fusing temperature, maintaining excellent hot offset and storage, and exhibiting a matte finish.

An image forming apparatus includes a plurality of developing member to form toner images, respectively, a transfer member to sequentially transfer the toner images onto a recording material and to overlappingly form toner on the recording material. A fixing member presses and heats the recording material on which the toner images are transferred and fixes the toner images on the recording material. A storage medium stores a usage history of the developing member. A controller controls a fixing temperature of the fixing member. The controller determines the fixing temperature based on a difference between the usage history of one of the developing member stored in the storage medium and the usage history of another of the developing member.

An image forming apparatus includes a plurality of developing member to form toner images, respectively, a transfer member to sequentially transfer the toner images onto a recording material and to overlappingly form toner on the recording material. A fixing member presses and heats the recording material on which the toner images are transferred and fixes the toner images on the recording material. A storage medium stores a usage history of the developing member. A controller controls a fixing temperature of the fixing member. The controller determines the fixing temperature based on a difference between the usage history of one of the developing member stored in the storage medium and the usage history of another of the developing member.

An image forming apparatus includes an image forming portion including a developer storage portion, a fixing apparatus, a detection portion configured to output a detection signal in accordance with a developer amount in the developer storage portion, and a control portion configured to control a target temperature of the fixing apparatus. The control portion is configured to set the target temperature at a first temperature if the developer amount is a first amount, set the target temperature at a second temperature lower than the first temperature if the developer amount is a second amount smaller than the first amount, and set the target temperature at a third temperature higher than the second temperature if the developer storage portion is supplied with the developer such that the developer amount is increased from the second amount to the first amount.