Toner, image forming apparatus, image forming method, process cartridge, and developer

Patent metadata

Field	Value
Publication number	US-9618864-B2
Application number	US-201414330109-A
Country	US
Kind code	B2
Filing date	Jul 14, 2014
Priority date	Sep 6, 2013
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

A toner comprised of mother toner particles each including a colorant, a resin A capable of forming a crystalline structure, and a resin B incapable of forming a crystalline structure is provided. The resin A is dispersed in the resin B in the state of phase separation. The long axis of each dispersed particle of the resin A has a length of from 30 to 200 nm and the length ratio of the long axis to the short axis is from 2 to 15. The DSC endothermic quantity attributable to the resin A is from 8 to 20 J/g.

First claim

What is claimed is:

1. A toner, comprising mother toner particles including:
a colorant;
a crystalline resin A,
an amorphous resin B, and
ethyl acetate in an amount of from 1 to 30 μg per 1 gram of the toner;
wherein the crystalline resin A is dispersed in the amorphous resin B in the state of phase separation,
wherein a long axis of each dispersed particle of the crystalline resin A has a length of from 30 to 200 nm and a length ratio of the long axis to a short axis is from 2 to 15, and
wherein a DSC endothermic quantity attributable to the crystalline resin A is from 8 to 20 J/g.

2. The toner according to claim 1 , wherein each of the mother toner particles has a core-shell structure.

3. The toner according to claim 1 , wherein the toner includes a polyester resin.

4. The toner according to claim 1 , wherein the toner includes a modified polyester resin.

5. The toner according to claim 1 , wherein the mother toner particles have an average circularity E of from 0.93 to 0.99.

6. The toner according to claim 1 , wherein a weight average particle diameter D4 of the toner is from 2 to 7 μm and a ratio (D4/Dn) of the weight average particle diameter D4 to a number average particle diameter Dn of the toner is from 1.00 to 1.25.

7. The toner according to claim 1 , wherein the toner is produced by a process including granulating in a medium containing water and/or an organic solvent.

8. The toner according to claim 1 , wherein the mother toner particles are produced by a dissolution suspension method.

9. The toner according to claim 1 , wherein the mother toner particles are produced by a dissolution suspension method accompanied by an elongation reaction.

10. The toner according to claim 1 , wherein the mother toner particles are produced by dispersing and/or emulsifying an organic phase and/or monomer phase in an aqueous medium, the organic phase and/or monomer phase including raw materials and/or precursors of the mother toner particles.

11. The toner according to claim 1 , wherein the mother toner particles are produced by subjecting a toner composition to a cross-linking and/or elongation reaction in an aqueous medium in the presence of fine resin particles, the toner composition including a polymer having a site reactive with a compound having an active hydrogen group, a polyester, a colorant, and a release agent.

12. A process cartridge, comprising:
a latent image bearing member;
a developing device; and
the toner according to claim 1 ,
wherein the process cartridge integrally supports the latent image bearing member and the developing device and is detachably attachable to image forming apparatus.

13. A two-component developer, comprising:
the toner according to claim 1 ; and
a magnetic carrier.

14. The toner according to claim 1 , having an average circularity of from 0.93 to 0.98.

15. The toner according to claim 1 , wherein a long axis of the crystalline resin A is from 31 to 190 nm.

16. The toner according to claim 1 , the ethyl acetate is present in an amount of from 3 to 22 μg per 1 gram of the toner.

Assignees

• Sugiura Hideki
• Mizoguchi Yuka
• Kumai Mio
• Ricoh Co Ltd

Inventors

• Sugiura Hideki
• Mizoguchi Yuka
• Kumai Mio

Classifications

• G03G9/0827

  characterised by their shape, e.g. degree of sphericity · CPC title

• G03G9/08755 Primary

  Polyesters · CPC title

• G03G9/0806

  whereby chemical synthesis of at least one of the toner components takes place · CPC title

• G03G9/09392

  Preparation thereof · CPC title

• G03G9/093

  Encapsulated toner particles · CPC title