Electrostatic image developing toner, electrostatic image developer, and toner cartridge

Patent metadata

Field	Value
Publication number	US-12436477-B2
Application number	US-202117497144-A
Country	US
Kind code	B2
Filing date	Oct 8, 2021
Priority date	May 25, 2021
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

An electrostatic image developing toner includes a toner particle including an amorphous resin, a crystalline resin, and a release agent. When a cross section of the toner particle is observed, the toner particle satisfies conditions (A1) and (B1) below: Condition (A1): one or more domains of the crystalline resin, the domains having a diameter equal to 10% or more and 40% or less of the maximum diameter of the toner particle, are present in the toner particle, and Condition (B1): one or more domains of the release agent, the domains having a diameter equal to 10% or more and 40% or less of the maximum diameter of the toner particle, are present in the toner particle.

First claim

What is claimed is:

1. An electrostatic image developing toner comprising a toner particle including:
an amorphous polyester resin;
a crystalline resin; and
a release agent, wherein when a cross section of the toner particle is observed, the toner particle satisfies conditions (A1) and (B1) below,
Condition (A1): one or more domains of the crystalline resin, the domains having a diameter equal to 10% or more and 40% or less of a maximum diameter of the toner particle, are present in the toner particle,
Condition (B1): one or more domains of the release agent, the domains having a diameter equal to 10% or more and 40% or less of the maximum diameter of the toner particle, are present in the toner particle; and
wherein a domain diameter of the crystalline resin is 1.1 μm or more and 2.0 μm or less,
wherein a proportion of the toner particles satisfying conditions (A1) and (B1) to all toner particles is 43% or more, and
wherein the release agent is an ester wax having a melting temperature of 85° C. or more and 95° C. or less or a polyethylene wax having a melting temperature of 91° C.

2. The electrostatic image developing toner according to claim 1 ,
wherein, when the cross section of the toner particle is observed, the toner particle satisfies conditions (A2) and (B2) below,
Condition (A2): a plurality of domains of the crystalline resin, the domains having a diameter equal to 10% or more and 40% or less of the maximum diameter of the toner particle, are present in the toner particle, and
Condition (B2): a plurality of domains of the release agent, the domains having a diameter equal to 10% or more and 40% or less of the maximum diameter of the toner particle, are present in the toner particle.

3. The electrostatic image developing toner according to claim 1 ,
wherein, when the cross section of the toner particle is observed, the toner particle satisfies condition (C1) below,
Condition (C1): the domains of the crystalline resin are acicular or tabular and the domains of the release agent are circular.

4. The electrostatic image developing toner according to claim 1 ,
wherein, when the cross section of the toner particle is observed, the toner particle satisfies condition (C2) below,
Condition (C2): the domains of the crystalline resin are circular and the domains of the release agent are acicular or tabular.

5. The electrostatic image developing toner according to claim 3 ,
wherein the acicular or tabular domains have an aspect ratio of 5 or more and 40 or less, and the circular domains have a circularity of 0.92 or more and 1.00 or less.

6. The electrostatic image developing toner according to claim 1 ,
wherein the proportion of the toner particles satisfying conditions (A1) and (B1) to all toner particles in the toner is 70% or more.

7. An electrostatic image developer comprising:
the electrostatic image developing toner according to claim 1 .

8. A toner cartridge detachably attachable to an image forming apparatus, the toner cartridge comprising:
the electrostatic image developing toner according to claim 1 .

9. The electrostatic image developing toner according to claim 1 ,
wherein the crystalline resin is a single type of crystalline resin in the toner particle.

10. The electrostatic image developing toner according to claim 1 ,
wherein a domain diameter of the release agent is 0.8 μm or more and 2.0 μm or less.

11. The electrostatic image developing toner according to claim 1 ,
wherein a domain diameter of the release agent is 1.0 μm or more and 2.0 μm or less.

12. The electrostatic image developing toner according to claim 1 , wherein the crystalline resin is a crystalline polyester resin, which is a condensation polymer of a polyvalent carboxylic acid and an aliphatic diol, the aliphatic diol comprising 80% by mol or more of an aliphatic diols having 7 to 20 carbon atoms.

13. The electrostatic image developing toner according to claim 1 , wherein the release agent is an ester wax having a melting temperature of 85° C. or more and 95° C. or less.

Assignees

• Fujifilm Business Innovation Corp

Inventors

• Sugawara Atsushi
• FUJIHARA Yoshimasa
• Noguchi Daisuke
• Anno Shintaro
• Miura Satoshi

Classifications

• G03G15/0868

  Toner cartridges fulfilling a continuous function within the electrographic apparatus during the use of the supplied developer material, e.g. toner discharge on demand, storing residual toner, acting as an active closure for the developer replenishing opening · CPC title

• G03G9/097

  Plasticisers; Charge controlling agents · CPC title

• G03G9/08755

  Polyesters · CPC title

• G03G9/0825

  characterised by their structure; characterised by non-homogenuous distribution of components (microcapsular toners G03G9/093) · CPC title

• G03G9/08797

  characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature · CPC title