Toner

Patent metadata

Field	Value
Publication number	US-2023015518-A1
Application number	US-202217808835-A
Country	US
Kind code	A1
Filing date	Jun 24, 2022
Priority date	Jul 2, 2021
Publication date	Jan 19, 2023
Grant date	—

Abstract

A toner comprising a toner particle comprising a binder resin, a nonmagnetic inorganic oxide particle A, and a magnetic iron oxide particle B, wherein a softening point of a chloroform-soluble component of the toner particle is not greater than 90° C.; the nonmagnetic inorganic oxide particle A and the magnetic iron oxide particle B are internally added to the toner particle; the nonmagnetic inorganic oxide particle A comprises as its main component at least one element selected from the group consisting of Si, Mg, Al, Ti, and Sr; a proportion of the inorganic oxide particles having a long diameter of specific length is in specific range; and a value of a ratio of a number-average particle diameter of the long diameter for the nonmagnetic inorganic oxide particle A, to a number-average particle diameter of the long diameter for the magnetic iron oxide particle B, is 5 to 30.

First claim

What is claimed is:

1 . A toner comprising a toner particle comprising
a binder resin, a nonmagnetic inorganic oxide particle A, and a magnetic iron oxide particle B, wherein a softening point of a chloroform-soluble component of the toner particle is not greater than 90° C.; the nonmagnetic inorganic oxide particle A and the magnetic iron oxide particle B are internally added to the toner particle; the nonmagnetic inorganic oxide particle A comprises as its main component at least one element selected from the group consisting of Si, Mg, Al, Ti, and Sr; among nonmagnetic inorganic oxide particles A having a long diameter of at least 100 nm, a proportion of particles having a long diameter of 400 to 3,000 nm is at least 70 number %; among the magnetic iron oxide particles B, a proportion of particles having a long diameter of 50 to 350 nm is at least 70 number %; and a value of a ratio (the nonmagnetic inorganic oxide particle A/the magnetic iron oxide particle B) of a number-average particle diameter of the long diameter for the nonmagnetic inorganic oxide particle A, to a number-average particle diameter of the long diameter for the magnetic iron oxide particle B, is 5 to 30.

2 . The toner according to claim 1 , wherein, in transmission electron microscopic observation of a cross section of the toner provided by sectioning with a microtome,
a value of a ratio (the magnetic iron oxide particle B/the nonmagnetic inorganic oxide particle A) of a number of magnetic iron oxide particles B to a number of nonmagnetic inorganic oxide particles A present in the cross section of the toner particle is 50 to 500.

3 . The toner according to claim 1 , wherein, in transmission electron microscopic observation of a cross section of the toner provided by sectioning with a microtome,
0.5 to 5.0 nonmagnetic inorganic oxide particles A are present per 1 toner cross section.

4 . The toner according to claim 1 , wherein, in transmission electron microscopic observation of a cross section of the toner provided by sectioning with a microtome,
a shape factor SF1 for the nonmagnetic inorganic oxide particle A is at least 140, and the shape factor SF1 for the magnetic iron oxide particle B is not more than 110.

5 . The toner according to claim 1 , wherein, among nonmagnetic inorganic oxide particles A having a long diameter of at least 100 nm, a proportion of particles having a long diameter of 800 to 3,000 nm is at least 70 number %.

6 . The toner according to claim 1 , wherein a value of a ratio (a weight-average particle diameter of the toner/a number-average particle diameter of the long diameter for the nonmagnetic inorganic oxide particle A) of a weight-average particle diameter of the toner to the number-average particle diameter of the long diameter for the nonmagnetic inorganic oxide particle A is 2 to 15.

7 . The toner according to claim 1 , wherein the nonmagnetic inorganic oxide particle A is a silica particle.

8 . The toner according to claim 1 , wherein the binder resin comprises an amorphous polyester resin.

9 . The toner according to claim 8 , wherein a content of the amorphous polyester resin in the binder resin is at least 50 mass %.

10 . The toner according to claim 1 , wherein the number-average molecular weight (Mn) of the binder resin is 1,000 to 5,000.

11 . The toner according to claim 1 , wherein the residual magnetization (σr) of the magnetic iron oxide particle B is 4 to 18 Am 2 /kg.

Assignees

• Canon Kk

Inventors

• Nozaki Dai
• Suzumura Yoshitaka
• Unno Tomohiro

Classifications

• G03G9/0819

  characterised by the dimensions of the particles · CPC title

• G03G9/0833

  Oxides · CPC title

• G03G9/08795

  characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants · CPC title

• G03G9/081 Primary

  by mixing the toner components in a liquefied state; melt kneading; reactive mixing · CPC title

• G03G9/08755 Primary

  Polyesters · CPC title