US 12,405,544 B2
Toner and method for producing toner
Tomohiro Unno, Shizuoka (JP); Dai Nozaki, Shizuoka (JP); and Yoshitaka Suzumura, Shizuoka (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Apr. 14, 2022, as Appl. No. 17/659,273.
Claims priority of application No. 2021-071560 (JP), filed on Apr. 21, 2021.
Prior Publication US 2022/0365457 A1, Nov. 17, 2022
Int. Cl. G03G 9/093 (2006.01); G03G 9/08 (2006.01)
CPC G03G 9/09328 (2013.01) [G03G 9/0821 (2013.01); G03G 9/0823 (2013.01); G03G 9/0825 (2013.01); G03G 9/09364 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A toner, comprising:
a toner particle having a core-shell structure comprising a core and a shell covering the core, a thickness of the shell being 100 to 200 nm in a cross section of the toner observed with a transmission electron microscope;
the core comprising a styrene-acrylic resin and a crystalline material;
the crystalline material being an ester wax in an amount of 5.00 to 50.00 parts by mass with respect to 100 parts by mass of the styrene-acrylic resin; and
the shell comprising an amorphous polyester resin within 100 nm from a surface of the toner particle, a content ratio of a monomer unit represented by formula (B) in the amorphous polyester resin being 30.0 to 50.0% by mass with respect to the mass of the amorphous polyester resin, a content ratio of a monomer unit represented by formula (C) in the amorphous polyester resin being 25.0 to 50.0% by mass with respect to the mass of the amorphous polyester resin, and a content ratio of a monomer unit represented by formula (D) in the amorphous polyester resin being 1.0 to 50.0% by mass with respect to the mass of the amorphous polyester resin

OG Complex Work Unit Chemistry
where R1 represents a benzene ring, R2 represents an ethylene or a propylene group, x and y are each an integer of 1 or more and an average value of x+y is 2 to 10, and R3 represents an ethylene or a propylene group, wherein
the toner has a softening point determined by a constant-load extrusion type capillary rheometer of 150° C. or less,
where a value obtained by dividing an amount of counted ions for a structure represented by formula (A) measured from the surface of the toner particle to a depth of 100 nm by time-of-flight secondary ion mass spectrometry by a total amount of counted ions is taken as a standard value

OG Complex Work Unit Chemistry
one or more peaks of the standard value are present within a range of 100 nm from the surface of the toner particle, and
1.15≤A(dmax)/A(0)≤5.00 and 0.010≤A(0)
where A(dmax) is a standard value of a peak having a maximum standard value among the one or more present peaks and A(0) is a standard value on the toner particle surface.