US 12,487,538 B2
Electrostatic charge image developing toner, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method
Tsutomu Furuta, Kanagawa (JP); Daisuke Ishizuka, Kanagawa (JP); Erina Saito, Kanagawa (JP); and Tomohito Nakajima, Kanagawa (JP)
Assigned to FUJIFILM Business Innovation Corp., Tokyo (JP)
Filed by FUJIFILM Business Innovation Corp., Tokyo (JP)
Filed on Apr. 29, 2022, as Appl. No. 17/732,522.
Claims priority of application No. 2021-157166 (JP), filed on Sep. 27, 2021.
Prior Publication US 2023/0103824 A1, Apr. 6, 2023
Int. Cl. G03G 9/087 (2006.01); G03G 9/08 (2006.01); G03G 15/08 (2006.01)
CPC G03G 9/08755 (2013.01) [G03G 9/0819 (2013.01); G03G 9/08711 (2013.01); G03G 15/08 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An electrostatic charge image developing toner comprising:
toner particles that contain a binder resin and crosslinked resin particles; and
an external additive that contains inorganic particles,
wherein a content of the binder resin with respect to a total amount of the toner particles is 40% by mass or more and 95% by mass or less,
a content of the crosslinked resin particles is 1% by mass or more and 30% by mass or less with respect to a total mass of the electrostatic charge image developing toner,
a content of the inorganic particles with respect to the toner particles is 0.1% by mass or more and 10% by mass or less,
a content of the inorganic particles with respect to a total mass of the external additive is 90% by mass or more and 100% by mass or less, a loss coefficient tan δa of the crosslinked resin particles at 40° C. and 0.1 rad/s satisfies 0.1<tan δa<1.0, a loss coefficient tan δb of the crosslinked resin particles at 40° C. and 10 rad/s satisfies 1.3<tan δb<3.0, and
in a case where a strain of 0.005% is applied to the toner at 40° C., a stress relaxation time τ of the toner satisfies 5 seconds<τ<500 seconds.