Toner and two-component developer

Patent metadata

Field	Value
Publication number	US-9678450-B2
Application number	US-201414783945-A
Country	US
Kind code	B2
Filing date	Apr 25, 2014
Priority date	Apr 26, 2013
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

Provided is [i] a toner including at least a colorant, a resin, and a releasing agent, wherein a spin-spin relaxation time (t 2 ) of the toner at 90° C. obtained by Hahn Echo method of pulse NMR analysis is from 1.80 msec to 7.00 msec. Also provided is [ii] a toner according to [i], wherein the spin-spin relaxation time (t 2 ) of the toner at 90° C. obtained by Hahn Echo method of pulse NMR analysis is from 3.80 msec to 5.90 msec.

First claim

The invention claimed is:

1. A toner, comprising:
a colorant;
a crystalline resin; and
a releasing agent,
wherein a spin-spin relaxation time (t 2 ) of the toner at 90° C. obtained by Hahn Echo method of pulse NMR analysis is from 1.80 msec to 7.00 msec,
wherein the crystalline resin comprises a crystalline polyester resin and the crystalline polyester resin comprises a urethane bond, a urea bond, or both thereof.

2. The toner according to claim 1 ,
wherein the spin-spin relaxation time (t 2 ) of the toner at 90° C. obtained by Hahn Echo method of pulse NMR analysis is from 3.80 msec to 5.90 msec.

3. The toner according to claim 1 ,
wherein of a soft component and a hard component of the toner at 90° C. obtained by Hahn Echo method of pulse NMR analysis, the hard component has a spin-spin relaxation time (t H ) that satisfies the following relational expression <1> or <2> where t S represents a spin-spin relaxation time attributed to the soft component:
when t S ≧25.00 msec, t H ≦2.00 msec  <1>,

when t S <25.00 msec, t H ≧1.10 msec  <2>.

4. The toner according to claim 1 , wherein in DSC of the toner in a range of from 0° C. to 100° C., a maximum endothermic peak temperature T1 of the toner at a first temperature raising and a maximum exothermic peak temperature T2 of the toner at a temperature lowering satisfy the following relational expression <3>:
T 1− T 2≦30.0° C. and T 2≧30.0° C.  <3>.

5. The toner according to claim 4 , wherein in the DSC of the toner in the range of from 0° C. to 100° C., a maximum endothermic peak temperature of the toner at a second temperature raising is in a range of from 50° C. to 70° C., and an amount of heat of melting of the toner at the second temperature raising is 30.0 J/g or greater.

6. The toner according to claim 1 , wherein when a tetrahydrofuran (THF) soluble content of the toner is measured with gel permeation chromatography (GPC), a ratio of a content of the THF soluble content that has a molecular weight of 100,000 or greater is 5% or greater, and a weight average molecular weight (Mw) of the THF soluble content is 20,000 or greater.

7. The toner according to claim 1 , wherein the toner has a core-shell structure, and a shell of the core-shell structure has a thickness of 40 nm or less.

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

9. The toner according to claim 1 , which further comprises a non-crystalline polyester resin.

10. The toner according to claim 9 , wherein the non-crystalline polyester resin is a modified polyester resin.

11. The toner according to claim 9 , wherein the non-crystalline polyester resin is an unmodified polyester resin.

12. The toner according to claim 1 , which contains 10% by mass to 85% by mass of the crystalline resin.

13. The toner according to claim 1 , which has a glass transition temperature of 40° C. to 70° C.

14. The toner according to claim 1 , which contains 1% by mass to 15% by mass of the colorant.

15. The toner according to claim 1 , wherein the releasing agent is a wax.

16. The toner according to claim 1 , wherein the releasing agent is a wax having a melting point of 40° C. to 160° C.

17. The toner according to claim 1 , wherein the releasing agent is a wax and the toner comprises up to 40% by mass of the wax.

18. The toner according to claim 1 , wherein the releasing agent is a wax and the toner comprises 3% by mass to 30% by mass of the wax.

Assignees

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

Inventors

• Kumai Mio
• Sugiura Hideki
• Mizoguchi Yuka

Classifications

• G03G9/08755

  Polyesters · CPC title

• G03G9/08795

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

• G03G9/093 Primary

  Encapsulated toner particles · CPC title

• G03G9/08797

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

• G03G9/08 Primary

  with toner particles · CPC title