Toner
A toner comprising a toner particle, the toner particle comprising a binder resin and a boric acid, wherein, where the toner particle is subjected to ATR-IR analysis by using germanium as an ATR crystal in an ATR method, a peak corresponding to the boric acid is detected, the toner comprises a fatty acid metal salt on a surface of the toner particle, and a presence ratio of an boron element on the surface of the toner particle is 0.01 atomic % or less as measured by X-ray photoelectron spectroscopy.
1 . A toner, comprising:
a toner particle comprising a binder resin and a boric acid;
a surface of the toner comprising a fatty acid metal salt, wherein
a peak corresponding to the boric acid is detected when the toner particle is subjected to ATR-IR analysis using germanium as an ATR crystal,
a presence ratio of a boron element on the surface of the toner particle is 0.01 atomic % or less measured by X-ray photoelectron spectroscopy, and
C/10<A×B when A (mol/μg) is a content of a metal element in the toner, B is a valence of a metal of the fatty acid metal salt, and C (mol/μg) is a content of boron in the toner.
2 . The toner according to claim 1 , wherein the binder resin comprises a resin capable of forming hydrogen bonds with the boric acid.
3 . The toner according to claim 1 , wherein a content of the boron element on a mass basis in the toner is 80 to 2000 ppm.
4 . The toner according to claim 1 , wherein in cross-sectional observation of the toner with a transmission electron microscope, As is 5.0% or less when As is an area ratio occupied by a release agent in a surface layer region from the surface of the toner particle to a depth of 1.0 μm.
5 . The toner according to claim 1 , wherein a content of the fatty acid metal salt in the toner is 0.05 to 0.50 parts by mass with respect to 100 parts by mass of the toner particle.
6 . The toner according to claim 1 , wherein when the toner is subjected to a dispersion treatment in a dispersion liquid comprising a sucrose and a surfactant in ion-exchanged water, an amount of the fatty acid metal salt migrated from the toner to the dispersion liquid is 0.04 to 0.20 parts by mass with respect to 100 parts by mass of the toner particle.
7 . The toner according to claim 2 , wherein the resin capable of forming hydrogen bonds with the boric acid comprises a polyester resin.
8 . The toner according to claim 2 , wherein the toner particle comprises a toner core particle and a shell on a surface of the toner core particle, and
the toner core particle comprises the boric acid and the resin capable of forming hydrogen bonds with the boric acid.
9 . The toner according to claim 8 , wherein the shell comprises the resin capable of forming hydrogen bonds with the boric acid.
10 . The toner according to claim 1 , wherein the fatty acid metal salt is a salt of a fatty acid having 16 to 20 carbon atoms and a polyvalent metal having a valence of 2 or more.
11 . The toner according to claim 10 , wherein the fatty acid metal salt is at least one member selected from the group consisting of zinc stearate, aluminum stearate and barium stearate.