Abstract External additive blending is one of the most important processes in toner manufacturing. It determines the electrostatic properties, powder properties, and physical properties of the toner, and therefore the xerographic performance of the toner. Additive-blending conditions, as well as additive compositions, have huge effects on several important toner properties such as the triboelectric charge level, charging rate, free flow, cohesiveness, and powder density. Understanding the additive-blending process and its effects on toner performance is of practical use in designing additive-blending processes and choosing optimal blending conditions. The effects of additive-blending conditions, such as blending intensity and blending temperature, have been studied, and their effects on toner properties and image quality have been tested. The temperature dependency of the blending process and hence the resulting properties and performances of the toner have not been studied extensively before, and this forms the purpose of this report. In most cases, the blending temperature during the additive-blending process is maintained at a fixed temperature, usually atmospheric temperature, or below, to remove the heat generated during high-speed blending. The blending temperature has an effect on additive adhesion, which indicates how effectively additives adhere to the toner surface after mechanical stress, which toner experiences in a cartridge during life.