Electrostatic latent image developing toner and electrostatic latent image developing toner set

Patent metadata

Field	Value
Publication number	US-12411430-B2
Application number	US-202217659230-A
Country	US
Kind code	B2
Filing date	Apr 14, 2022
Priority date	Jun 2, 2021
Publication date	Sep 9, 2025
Grant date	Sep 9, 2025

Abstract

Provided is an electrostatic latent image developing toner including: toner base particles containing a binder resin and a white pigment; and an external additive, wherein silica particles are contained as the external additive, and the following relational expression (1) is satisfied, Relational expression (1): 0.70≤Wh_Si(B)/Wh_Si(A)≤0.95, in the above relational expression (1), Wh_Si (A) represents an NET intensity of a Si element contained in the white electrostatic latent image developing toner measured by wavelength dispersive X-ray fluorescence spectrometer, and Wh_Si (B) represents an NET intensity of a Si element contained in the white electrostatic latent image developing toner that has been ultrasonically dispersed in water.

First claim

What is claimed is:

1. An electrostatic latent image developing toner set comprising:
a white electrostatic latent image developing toner containing toner base particles containing a first binder resin and a white pigment, and a first external additive; and
a colored electrostatic latent image developing toner including toner base particles containing a second binder resin and a colored colorant other than the white pigment, and a second external additive,
wherein silica particles are contained as the first and second external additives, and the following relational expressions (1) and (3) are satisfied,
0.70≤Wh_Si( B )/Wh_Si( A )≤0.95   Relational expression (1):

0.2≤(Wh_Si( B )/Wh_Si( A ))−(Co_Si( B )/Co_Si( A ))≤0.5  Relational expression (3):

wherein Wh_Si(A) represents an NET intensity of a Si element contained in the white electrostatic latent image developing toner measured by wavelength dispersive X-ray fluorescence spectrometer,
Wh_Si(B) represents an NET intensity of the Si element contained in the white electrostatic latent image developing toner that has been ultrasonically dispersed in water,
Co_Si(A) represents an NET intensity of a Si element contained in the colored electrostatic latent image developing toner as measured by the wavelength dispersive X-ray fluorescence spectrometer, and
Co_Si(B) represents an NET intensity of the Si element contained in the colored electrostatic latent image developing toner that has been ultrasonically dispersed in water, as measured by the wavelength dispersive X-ray fluorescence spectrometer.

2. The electrostatic latent image developing toner set according to claim 1 ,
wherein the first external additive in the white electrostatic latent image developing toner further contains titanium dioxide particles; and
a number average primary particle diameter of the titanium dioxide particles is in the range of 60 to 120 nm.

3. The electrostatic latent image developing toner set according to claim 2 , wherein the number average primary particle diameter of the titanium dioxide particles is larger than the number average primary particle diameter of the silica particles in the first external additive.

Assignees

• Konica Minolta Inc

Inventors

• Ueda Junya
• Maruyama Yohei
• Obara Shinya

Classifications

• G03G9/08755

  Polyesters · CPC title

• G03G9/0819

  characterised by the dimensions of the particles · CPC title

• G03G9/09708

  Inorganic compounds · CPC title

• G03G9/0902

  Inorganic compounds · CPC title

• G03G9/09725 Primary

  Silicon-oxides; Silicates · CPC title