TONER

• US 20190332027A1
• Filed: 04/23/2019
• Published: 10/31/2019
• Est. Priority Date: 04/27/2018
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kenmoku, Takashi, Amano, Shota, Unno, Tomohiro, Kyuushima, Hirofumi
• Granted Patent: US 10,747,136 B2
• Time in Patent Office: Days
• CPC Class Codes: G03G 9/0804 whereby the components are brought together in a liquid dispersing medium
• CPC Class Codes: G03G 9/0806 whereby chemical synthesis of at least one of the toner components takes place
• CPC Class Codes: G03G 9/0819 characterised by the dimensions of the particles
• CPC Class Codes: G03G 9/0823 Electric parameters
• CPC Class Codes: G03G 9/08795 characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants
• CPC Class Codes: G03G 9/09708 Inorganic compounds

Abstract

A toner comprising a toner particle having a binder resin and a colorant, and metal titanate fine particles, wherein the toner particle includes a polyvalent metal element having an electric resistivity of from 2.5×10⁻⁸ Ω·m to 10.0×10⁻⁸ Ω·m; the amount of the polyvalent metal element in the toner particle is from 0.080 μmol/g to 20.000 μmol/g; the metal titanate fine particles have a perovskite crystal structure; and the number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.

Claims

1. A toner comprising:

a toner particle containing a binder resin and a colorant, and

metal titanate fine particles,

wherein

the toner particle includes a polyvalent metal element having an electric resistivity of from 2.5×

10<sup>−

8</sup> Ω

·

m to 10.0×

10<sup>−

8</sup> Ω

·

m at 20°

C.;

the amount of the polyvalent metal element in the toner particle is from 0.080 μ

mol/g to 20.000 μ

mol/g;

the metal titanate fine particles have a perovskite crystal structure; and

the number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 80 nm.

2. The toner according to claim 1, wherein

a fixing ratio of the metal titanate fine particles on the toner particle surface is from 60% to 100%;

and

a coverage ratio of the metal titanate fine particles on the toner particle surface measured with an X-ray photoelectron spectrometer is from 0.5% by area to 20.0% by area.

3. The toner according to claim 1, wherein the polyvalent metal element is at least one selected from the group consisting of aluminum, iron, magnesium, and calcium.

4. The toner according to claim 1, wherein

the binder resin includes a carboxyl group;

the polyvalent metal element is at least one selected from the group consisting of aluminum, iron, magnesium, and calcium;

when the polyvalent metal element includes aluminum, the amount of aluminum in the toner particle is from 0.080 μ

mol/g to 0.400 μ

mol/g;

when the polyvalent metal element includes iron, the amount of iron in the toner particle is from 0.250 μ

mol/g to 1.250 μ

mol/g;

when the polyvalent metal element includes magnesium, the amount of magnesium in the toner particle is from 2.000 μ

mol/g to 20.000 μ

mol/g; and

when the polyvalent metal element includes calcium, the amount of calcium in the toner particle is from 2.000 μ

mol/g to 20.000 μ

mol/g.

5. The toner according to claim 1, wherein the metal titanate fine particles include strontium titanate fine particles.

6. The toner according to claim 5, wherein in an X-ray diffraction spectrum of CuKα

obtained in the range of 2θ

of from 10°

to 90°

, with θ

being a Bragg angle of the strontium titanate fine particles, peaks derived from the strontium titanate fine particles are at 39.700°

±

0.150° and

46.200°

±

0.150°

; and

when an area of the peak at 39.700°

±

0.150°

is denoted by Sa and an area of the peak at 46.200°

±

0.150°

is denoted by Sb, Sb/Sa is from 1.80 to 2.30.

7. The toner according to claim 1, wherein the number average particle diameter of primary particles of the metal titanate fine particles is from 10 nm to 60 nm.

8. The toner according to claim 1, wherein the binder resin has an acid value of from 1.0 mg KOH/g to 40.0 mg KOH/g.

9. The toner according to claim 1, wherein the toner particle is an emulsion aggregation toner particle.