US 11,768,446 B2
Toner production method
Shoichi Murata, Wakayama (JP); Manabu Suzuki, Wakayama (JP); and Yuki Wakabayashi, Chiba (JP)
Assigned to KAO CORPORATION, Tokyo (JP)
Appl. No. 16/967,274
Filed by KAO CORPORATION, Tokyo (JP)
PCT Filed Feb. 8, 2019, PCT No. PCT/JP2019/004694
§ 371(c)(1), (2) Date Aug. 4, 2020,
PCT Pub. No. WO2019/156231, PCT Pub. Date Aug. 15, 2019.
Claims priority of application No. 2018-021174 (JP), filed on Feb. 8, 2018.
Prior Publication US 2021/0033993 A1, Feb. 4, 2021
Int. Cl. G03G 9/087 (2006.01); G03G 9/08 (2006.01); G03G 9/09 (2006.01)
CPC G03G 9/0804 (2013.01) [G03G 9/0819 (2013.01); G03G 9/0827 (2013.01); G03G 9/08711 (2013.01); G03G 9/08755 (2013.01); G03G 9/0904 (2013.01)] 20 Claims
 
1. A method for producing a toner, the method comprising:
aggregating and coalescing resin particles and colorant particles in an aqueous medium, wherein
the resin particles comprise a composite resin comprising a polyester resin segment, an addition polymer resin segment which is an addition polymerized product of a raw material monomer comprising a styrenic compound, and a structural unit derived from a bireactive monomer bonding to the polyester resin segment and the addition polymer resin segment via a covalent bond,
the colorant particles comprise carbon black having a dibutyl phthalate oil absorption amount of from 20 ml/100 g to 50 ml/100 g as a colorant and an addition polymer of a raw material monomer comprising a styrenic compound, where the addition polymer in the colorant particles comprises a structural unit derived from the styrenic compound in the main chain, and wherein a pH value of carbon black is from 5 to 6.8, and
a ratio by mass of the colorant to the addition polymer in the colorant particles is from 50/50 to 95/5.