Toner, development agent, image forming apparatus, and process cartridge

Patent metadata

Field	Value
Publication number	US-9176406-B2
Application number	US-201313958745-A
Country	US
Kind code	B2
Filing date	Aug 5, 2013
Priority date	Aug 17, 2012
Publication date	Nov 3, 2015
Grant date	Nov 3, 2015

Abstract

Toner contains a binder resin containing a crystalline resin having a urethane and/or urea bonding; and a colorant, wherein in a diffraction spectrum of the toner as measured by an X-ray diffraction instrument, a ratio {C/(C+A)} of an integral intensity C of the spectrum derived from the crystalline structure to an integral intensity A of the spectrum derived from the non-crystalline structure is 0.12 or greater, wherein the toner satisfies the following relation 1: T1−T2≦30° C. (Relation 1), where T1 represents the maximum endothermic peak in the first temperature rising from 0° C. to 100° C. at the temperature rising rate of 10° C./min and T2 represents the maximum exothermic peak in the first temperature falling from 100° C. to 0° C. at the temperature falling rate of 10° C./min as T1 and T2 are measured by diffraction scanning calorimetry (DSC).

First claim

What is claimed is:

1. A toner, comprising:
a binder resin comprising a crystalline polyester resin having a urethane and/or urea bonding; and
a colorant,
wherein in a diffraction spectrum of the toner as measured by an X-ray diffraction instrument, a ratio {C/(C+A)} of an integral intensity C of a spectrum derived from a crystalline structure to an integral intensity A of a spectrum derived from a non-crystalline structure is 0.16 or greater,
wherein the toner satisfies the following relation 1:
T 1− T 2≦30° C.  Relation 1

where T1 represents a maximum endothermic peak in a first temperature rising from 0° C. to 100° C. at a temperature rising rate of 10° C./min and T2 represents a maximum exothermic peak in a first temperature falling from 100° C. to 0° C. at a temperature falling rate of 10° C./min as T1 and T2 are measured by diffraction scanning calorimetry (DSC).

2. The toner according to claim 1 , wherein T2 satisfies the following relation 2:
T 2≧30° C.  Relation 2

3. The toner according to claim 1 , wherein the crystalline polyester resin further comprises a non-modified crystalline resin.

4. The toner according to claim 3 , wherein a ratio of the non-modified crystalline polyester resin is from 2% by weight to less than 50% by weight in the crystalline resin.

5. The toner according to claim 1 , further comprising a nucleating agent.

6. The toner according to claim 1 , wherein a melt molded product of the toner has a Martens hardness of 20 N/m 2 or more at 50° C.

7. The toner according to claim 1 ,
wherein a tetrahydrofuran soluble of the toner contains a component having a molecular weight of 100,000 or greater in an amount of 5.0% or greater of a peak area in a molecular weight distribution as measured by gel permeation chromatography,
wherein a ratio of decomposed residue of the tetrahydrofuran soluble insoluble in methanol is 5.0% by weight or greater when the tetrahydrofuran soluble is decomposed in 0.1 N KOH methanol solution.

8. The toner according to claim 1 , wherein the crystalline polyester resin having a urethane and/or urea bonding comprises a crystalline polyester polyester resin having a urea bonding.

9. The toner according to claim 1 , wherein the crystalline polyester resin having a urethane and/or urea bonding comprises a crystalline polyester resin having a urethane and/or urea bonding formed by elongating a modified crystalline polyester resin having an isocyanate group at an end thereof.

10. The toner according to claim 1 , wherein TI satisfies the following relation 3:
50° C.< T 1<70° C.  Relation 3.

11. The toner according to claim 1 , prepared by granulating toner particles by dispersing and/or emulsifying in an aqueous medium an oil phase in which a toner composition comprising a binder resin, a coloring agent, and an organically modified laminate inorganic mineral is dissolved and/or dispersed in an organic solvent.

12. The toner according to claim 11 , wherein elongation reaction is conducted between an active hydrogen group and a modified crystalline polyester resin having an isocyanate group at an end thereof when granulating the toner particles by dispersion and/or emulsification in the aqueous medium.

13. A development agent comprising:
the toner of claim 1 ; and
carrier.

14. The toner according to claim 1 , which further comprises a releasing agent.

15. The toner according to claim 14 , wherein the releasing agent accounts for 3 parts by weight to 10 parts by weight to 100 parts by weight of the toner.

16. The toner according to claim 1 , wherein the content of the crystalline polyester resin in the toner is 75% by weight or more.

17. The toner according to claim 1 , wherein the content of the crystalline polyester resin in the toner is 80% by weight or more.

18. A process cartridge comprising:
a latent electrostatic image bearing member to bear a latent electrostatic image; and
a development device to develop the latent electrostatic image with a toner to form a visible image, wherein the development device contains the toner of claim 1 ,
wherein the process cartridge is detachably attachable to an image forming apparatus.

Assignees

• Sekiguchi Satoyuki
• Yamashita Hiroshi
• Masuda Minoru
• Chiba Susumu
• Morita Tatsuya
• Yamamoto Atsushi
• Nakayama Shinya
• Yamada Masahide
• Nagata kohsuke
• Makabe Keiji
• Sawada Toyoshi
• Ricoh Co Ltd

Inventors

• Sekiguchi Satoyuki
• Yamashita Hiroshi
• Masuda Minoru
• Chiba Susumu
• Morita Tatsuya
• Yamamoto Atsushi
• Nakayama Shinya
• Yamada Masahide
• Nagata kohsuke
• Makabe Keiji
• Sawada Toyoshi

Classifications

• G03G9/08764 Primary

  Polyureas; Polyurethanes · CPC title

• G03G9/08755

  Polyesters · CPC title

• G03G9/08795

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

• G03G9/08797

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

• G03G9/0804

  whereby the components are brought together in a liquid dispersing medium · CPC title