IP Library › Granted Patent US 8,211,605
Granted Patent B2
US 8,211,605 · App. 12/050,502 · Granted Jul 3, 2012

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

Assignee: Ricoh Company, Ltd.
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Quick Facts
Patent No.
US 8,211,605
App. No.
12/050,502
Granted
Jul 3, 2012
Kind
B2
Abstract

There is provided a toner which contains at least a binder resin, and filler including a layered inorganic compound, wherein the layered inorganic compound is cleaved to form particles in the toner, and the particles have a breadth of 0.5 nm to 4 nm, and a length of 10 nm to 90 nm.

Claims (40)

1. A toner comprising at least:

a binder resin; and

filler comprising a layered inorganic compound,

wherein the layered inorganic compound is a smectite group clay mineral cleaved to form particles in the toner, and the particles have a breadth of 0.5 nm to 4 nm, and a length of 10 nm to 90 nm, and

wherein the smectite group clay mineral is a synthetic smectite expressed by the following general formula 1:

Na 0.1-1.0 Mg 2.4-2.9 Li 0.1-0.6 Si 3.5-4.5 O 9.5-10.5 (X) 1.5-2.5   General formula 1

wherein X denotes at least one selected from OH and F, and

wherein the synthetic smectite is obtained by a process comprising reacting a mixed solution of silicic acid and magnesium salt with an alkaline solution to synthesize a silicon-magnesium complex, removing electrolyte which is a by-product of the reaction, adding lithium ions together with at least one selected from sodium ions and fluorine ions to the silicone-magnesium complex so as to subject the mixture to a hydrothermal reaction.

2. The toner according to claim 1 , wherein the toner has a filler layer comprising the layered inorganic compound in an area adjacent to a surface of the toner.

3. The toner according to claim 1 , wherein a content of the layered inorganic compound in the toner is 0.5% by mass to 5% by mass.

4. The toner according to claim 1 , wherein the layered inorganic compound has a cation exchange capacity of 80 me/100 g to 120 me/100 g.

5. The toner according to claim 1 , wherein the toner is obtained by a process comprising dissolving or dispersing a toner material comprising an active hydrogen group containing compound, a polymer reactive with the active hydrogen group containing group, a binder resin and the filler in an organic solvent so as to prepare a toner solution, emulsifying or dispersing the toner solution in an aqueous medium so as to prepare an emulsified dispersion, reacting the active hydrogen group containing compound and the polymer reactive with the active hydrogen group containing compound in the aqueous medium so as to generate an adhesive base in the shape of particles, and removing the organic solvent.

6. The toner according to claim 5 , wherein the organic solvent is ethyl acetate.

7. The toner according to claim 5 , wherein the binder resin comprises non-modified polyester, and wherein a mass ratio (polymer/non-modified polyester) of the polymer reactive with the active hydrogen group containing compound to the non-modified polyester is 5/95 to 80/20.

8. The toner according to claim 1 , wherein the toner has an average circularity of 0.925 to 0.970.

9. The toner according to claim 1 , wherein the toner has a volume average diameter (Dv) of 3 μm to 10 μm, and a ratio (Dv/Dn) of 1.00 to 1.30 wherein the ratio (Dv/Dn) is a ratio of the volume average particle diameter to a number average particle diameter.

10. A developer comprising:

a carrier; and

the toner of claim 1 .

11. An image forming method, comprising:

forming a latent electrostatic image on a latent electrostatic image bearing member;

developing the latent electrostatic image using the toner of claim 1 so as to form a visible image;

transferring the visible image onto a recording medium; and

fixing the transferred image on the recording medium.

12. A toner comprising at least:

a binder resin; and

filler comprising a layered inorganic compound,

wherein the layered inorganic compound comprises a synthetic smectite expressed by the following general formula 1:

Na 0.1-1.0 Mg 2.4-2.9 Li 0.1-0.6 Si 3.5-4.5 O 9.5-10.5 (X) 1.5-2.5   General formula 1

wherein X denotes at least one selected from OH and F, and

wherein the synthetic smectite is obtained by a process comprising reacting a mixed solution of silicic acid and magnesium salt with an alkaline solution to synthesize a silicon-magnesium complex, removing electrolyte which is a by-product of the reaction, adding lithium ions together with at least one selected from sodium ions and fluorine ions to the silicone-magnesium complex so as to subject the mixture to a hydrothermal reaction.

13. The toner according to claim 12 , wherein the toner is obtained by a process comprising dissolving or dispersing a toner material comprising an active hydrogen group containing compound, a polymer reactive with the active hydrogen group containing group, a binder resin and the filler in an organic solvent so as to prepare a toner solution, emulsifying or dispersing the toner solution in an aqueous medium so as to prepare an emulsified dispersion, reacting the active hydrogen group containing compound and the polymer reactive with the active hydrogen group containing compound in the aqueous medium so as to generate an adhesive base in the shape of particles, and removing the organic solvent.

14. A developer comprising:

a carrier; and

the toner of claim 12 .

15. An image forming method, comprising:

forming a latent electrostatic image on a latent electrostatic image bearing member;

developing the latent electrostatic image using the toner of claim 12 so as to form a visible image;

transferring the visible image onto a recording medium; and

fixing the transferred image on the recording medium.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 18, 2008
From: YAMADA, HIROSHI; MOCHIZUKI, SATOSHI; SASAKI, FUMIHIRO; ASAHINA, YASUO; NAKAJIMA, HISASHI
To: RICOH COMPANY, LTD.
Reel/Frame 020667/0440 →
Priority Claims (1)
JP 2007-071281 · Mar 19, 2007 · national
Continuity (1)
Related Publication 20080233498A1 · Sep 25, 2008