US 12,339,620 B2
Toner
Maki Imura, Chiba (JP); Tomoyo Miyakai, Tokyo (JP); Kentaro Kamae, Kanagawa (JP); Yuu Nishimura, Chiba (JP); Shin Kitamura, Ibaraki (JP); and Takaho Shibata, Tokyo (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Apr. 28, 2022, as Appl. No. 17/661,168.
Claims priority of application No. 2021-080709 (JP), filed on May 12, 2021.
Prior Publication US 2022/0373919 A1, Nov. 24, 2022
Int. Cl. G03G 9/097 (2006.01); G03G 9/08 (2006.01); G03G 9/087 (2006.01)
CPC G03G 9/09791 (2013.01) [G03G 9/0821 (2013.01); G03G 9/0825 (2013.01); G03G 9/08755 (2013.01)] 7 Claims
 
1. A toner comprising a toner particle,
the toner particle comprising
a binder resin, and
a water-soluble polyvalent metal salt, wherein
a main component of the binder resin is a polyester resin;
an acid value of the polyester resin is 1.0 mgKOH/g to 30.0 mgKOH/g;
a polyvalent metal of the water-soluble polyvalent metal salt is at least one metal selected from the group consisting of Mg, Ca, Al, Fe and Zn;
the water-soluble polyvalent metal salt is a chloride, nitrate or sulfate of the polyvalent metal;
the water-soluble polyvalent metal salt has a solubility in water at 25° C. of 30 g/100 mL to 200 g/100 mL;
in a cross-sectional observation of the toner particle using a transmission electron microscope, a proportion of an area of domains derived from the water-soluble polyvalent metal salt and having an area of 0.002 μm2 to 0.050 μm2, relative to a total area of the domains derived from the water-soluble polyvalent metal salt, is 80 area % to 100 area %; and
Expression (1) below is satisfied, where At (area %) is the proportion of the total area of the domains derived from the water-soluble polyvalent metal salt relative to an area of a cross section of the toner particle, and Fm (atomic %) is a proportion of an atom of the polyvalent metal relative to atoms in the toner as detected by X-ray fluorescence analysis
0.02≤At/Fm≤0.10  (1).