| abstract |
A toner for developing electrostatic images is constituted as a powdery mixture of toner particles, inorganic fine powder, resin fine particles, and metal oxide particles. The toner has a weight-average particle size of 4-12 mu m and contains at most 30% by number of particles having a particle size of at most 3.17 mu m. The inorganic fine powder has an average primary particle size of 1-50 nm. The resin fine particles have an average particle size of 0.1-2 mu m and a shape factor SF1 of at least 100 and below 150. The metal oxide particles have an average particle size of 0.3-3 mu m and a shape factor SF1 of 150-250. The toner is effective for preventing toner sticking onto and ununiform abrasion of the electrostatic image-bearing member to allow the formation of high-quality images for a long life. |