TWI790365B

This sublimation transfer toner comprises toner base particles produced by surface-modifying a pulverized toner, which is a ground and classified product of a mixture containing at least a binding resin and a sublimation dye, and an external additive which is adhered to the toner base particles, wherein said toner base particles produced from the surface-modified pulverized toner have silica as a fluidizer, said silica being embedded into the recesses and cracks in the surface of the pulverized toner and immobilized by thermal treatment. Silica is adhered as an external additive to the surface of the toner base particles. The volume-based median diameter D50 of the toner is 4 μm to 10 μm. The average circularity of the toner is 0.930 to 0.980. The glass transition temperature of the toner is 53°C to 70°C. When A0 is defined as the specific surface area of a sphere in terms of the volume-based median diameter D50 of the toner, and A1 is defined as the BET specific surface area of a washed toner produced by add