Patent ID: 10747134

Abstract:
An external toner additive having a resin fine particle containing a crystalline resin and an inorganic fine particle embedded in the resin fine particle, wherein part of the inorganic fine particle is exposed on the surface of the resin fine particle, and in differential scanning calorimetry of the external toner additive, the maximum endothermic peak temperature T1 (° C.) during a first temperature increase and the maximum exothermic peak temperature T2 (° C.) during a first temperature decrease satisfy the formulae (1) to (3) below, with measurement performed between −40° C. and 150° C. at a rate of increase of 10° C./min during the first temperature increase and between 150° C. and −40° C. at a rate of decrease in temperature of 10° C./min during the first temperature decrease: T1-T2≤40.0  (1)50.0≤T1≤120.0  (2)10.0≤T2≤80.0  (3).