US Patent 10935902 Toner

A toner including a toner particle that includes a binder resin and a crystalline polyester; and inorganic fine particles on the toner particle surface, wherein a content of the crystalline polyester is 0.5 to 20.0 mass parts per 100 mass parts of the binder resin; in the toner cross section, domains of the crystalline polyester are present in a dispersed state, the percentage for areas of these crystalline polyester domains in the region to a depth of 0.50 μm from a contour of the toner particle is at least 10%, the number average of lengths of a major axis is 120 nm to 1000 nm, and the number average of aspect ratios is not more than 4; a dielectric constant of the inorganic fine particles is 25 to 300 pF/m; and a coverage ratio by the inorganic fine particles on the toner particle surface is 5% to 60%.