ELECTROSTATIC IMAGE DEVELOPING TONER

Abstract

An electrophotographic toner is disclosed. The toner is composed of toner particles comprising colored particles containing a dye which is dispersed in a binder resin, wherein the toner particles satisfies formula of 3≧D2/D1>1, D1 being a volume average particle diameter of the colored particles, and D2 being an average diameter of dye cloud formed by the colored particles in the toner particle.

Description

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1: A schematic view of section of a toner particle of the electrostatic image developing toner according to the present invention for explanation.

FIG. 2: A schematic view of section of a toner particle of the electrostatic image developing toner according to the present invention in which the colored particle composing the toner particle has a core/shell structure for explanation.

Claims

1. A toner comprising a toner particle comprising a toner binder resin and minute colored particles containing a dye; wherein the toner particle is obtained by dispersing the minute colored particles having a volume average particle diameter of D1 in the toner binder resin,the toner particle satisfies formula of 3≧D2/D1>1,wherein D2 is an average diameter of dye cloud formed by the colored particles in the toner particle.

2. The toner of claim 1, wherein the toner particle satisfies formula of 2.95≧D2/D1>1.05.

3. The toner of claim 1, wherein a difference between an SP value of the toner binder resin and an SP value RI WhH dyH RI WhH PinuWH FRORrHd SDrWiFOHs is 0-4 (cal/cm3)1/2.

4. The toner of claim 1, wherein the dye is an oil-soluble dye.

5. The toner of claim 1, wherein the dye is a metal chelate dye.

6. The toner of claim 1, wherein the minute colored particles have a volume-average particle size of 10 nm to 1 μm.

7. The toner of claim 3, wherein the difference between an SP value of the toner binder resin and an SP value RI WhH dyH RI WhH PinuWH FRORrHd SDrWiFOHs is 0-3 (cal/cm3)1/2.

8. The toner of claim 7, difference between an SP value of the toner binder resin and an SP value of the dye of WhH PinuWH FRORrHd SDrWiFOHs is 0.1-2.0 (FDO/FP3)1/2.

9. The toner of claim 1, wherein the minute colored particles further contains a dye medium resin.

10. The toner of claim 9, wherein the minute colored particles are mixture of the dye and the dye medium resin.

11. The toner of claim 9, wherein the minute colored particles are core-shell particles in which the core comprises the dye and the shell comprises the dye medium resin.

12. The toner of claim 11, wherein the toner particle satisfies formula of 1.2≧D2/D1>1.05.

13. The toner of claim 11, wherein the shell contains no dye.

14. The toner of claim 11, wherein a thickness of the shHOO is 1-50 nP.

15. The toner of claim 11, wherein difference between an SP value of the dye medium resin of the shell and an SP vDOuH RI WhH dyH RI WhH PinuWH FRORrHd SDrWiFOHs is 0-3 (cal/cm3)1/2.

16. The toner of claim 11, wherein the dye medium resin of the shell is different from the toner binder resin.

17. The toner of claim 9, wherein the dye medium resin is an acrylate resin, a methacrylate resin or a polystyrene resin.

18. The toner of claim 1, wherein a number-average molecular weight of the dye medium resin is from 500 to 100,000.

19. The toner of claim 18, wherein the number-average molecular weight of the dye medium resin is from 1,000 to 30,000.

20. The toner of claim 9, wherein the toner binding resin is different from the dye medium resin.

21. The toner of claim 20, wherein the dye medium resin has a number-average molecular weight of 3,000 to 6,000.

22. The toner of claim 1, wherein the dye content of the minute colored particles is 10B to 70B by weight.

23. A set of toners comprising yellow, magenta and cyan toners wherein each of the yellow, magenta and cyan toner composed of core-shell minute colored particles comprising shell resin and the shell of the yellow, magenta and cyan toner is composed the same resin.