IP Library Granted Patent US 8,828,634
Granted Patent B2
US 8,828,634 · App. 13/223,957 · Granted Sep 9, 2014

Electrostatic charge image developing toner, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

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Quick Facts
Patent No.
US 8,828,634
App. No.
13/223,957
Granted
Sep 9, 2014
Kind
B2
Abstract

The electrostatic charge image developing toner includes a colorant containing rutile type and anatase type titanium oxides, and a binder resin.

Claims (34)

1. An electrostatic charge image developing toner comprising:

a binder resin; and

a white colorant dispersed in the toner,

wherein the colorant includes a rutile type titanium oxide and an anatase type titanium oxide, and

wherein the total amount of rutile type titanium oxide and anatase type titanium oxide of the total amount of colorants is from 80% to 100% by weight.

2. The electrostatic charge image developing toner according to claim 1 , wherein a mass ratio between the rutile type titanium oxide and the anatase type titanium oxide is 90:10 to 50:50.

3. The electrostatic charge image developing toner according to claim 1 , wherein the amount of the colorant is from about 30% by mass to about 60% by mass based on the total mass of the toner.

4. The electrostatic charge image developing toner according to claim 1 , wherein a mass ratio between the rutile type titanium oxide and the anatase type titanium oxide is 80:20 to 60:40.

5. The electrostatic charge image developing toner according to claim 1 , wherein the volume average particle size of the rutile type titanium oxide and the anatase type titanium oxide is from about 100 nm to about 400 nm.

6. The electrostatic charge image developing toner according to claim 1 , wherein the volume average particle size of the rutile type titanium oxide and the anatase type titanium oxide is from about 200 nm to about 300 nm.

7. An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 1 .

8. The electrostatic charge image developer according to claim 7 , further comprising a carrier.

9. The electrostatic charge image developer according to claim 7 , wherein the electrostatic charge image developing toner contains a white colorant in which a mass ratio between the rutile type titanium oxide and the anatase type titanium oxide is 90:10 to 50:50.

10. The electrostatic charge image developer according to claim 7 , wherein the electrostatic charge image developing toner contains a colorant in which the volume average particle size of the rutile type titanium oxide and the anatase type titanium oxide is from about 100 nm to about 400 nm.

11. A process cartridge accommodating the electrostatic charge image developer according to claim 7 , comprising a developing unit that develops an electrostatic charge image formed on the surface of a latent image holding member by using the electrostatic charge image developer to form a toner image, and being detachable from an image forming apparatus.

12. An image forming apparatus comprising:

a latent image holding member;

a charging unit that charges the surface of the latent image holding member;

an electrostatic charge image forming unit that forms an electrostatic charge image on the surface of the latent image holding member;

a developing unit that develops the electrostatic charge image by using the electrostatic charge image developer according to claim 8 to form a toner image;

a transfer unit that transfers the toner image to a recording medium; and

a fixing unit that fixes the toner image to the recording medium.

13. The image forming apparatus according to claim 12 , wherein the electrostatic charge image developing toner contains a white colorant in which a mass ratio between the rutile type titanium oxide and the anatase type titanium oxide is 90:10 to 50:50.

14. The image forming apparatus according to claim 12 , wherein the electrostatic charge image developing toner contains a colorant in which the volume average particle size of the rutile type titanium oxide and the anatase type titanium oxide is from about 100 nm to about 400 nm.

15. An image forming method comprising:

charging the surface of a latent image holding member;

forming an electrostatic charge image on the surface of the latent image holding member;

developing the electrostatic charge image by using the electrostatic charge image developer according to claim 8 to form a toner image;

transferring the toner image to a recording medium; and

fixing the toner image to the recording medium.

16. The image forming method according to claim 15 , wherein the electrostatic charge image developing toner contains a white colorant in which a mass ratio between the rutile type titanium oxide and the anatase type titanium oxide is 90:10 to 50:50.

17. The image forming method according to claim 15 , wherein the electrostatic charge image developing toner contains a colorant in which the volume average particle size of the rutile type titanium oxide and the anatase type titanium oxide is from about 100 nm to about 400 nm.

18. A toner cartridge comprising the electrostatic charge image developing toner according to claim 1 inside a container thereof and being detachable from an image forming apparatus.

19. The electrostatic charge image developing toner according to claim 1 , wherein the colorant is present in the toner in an amount of from about 40% by mass to about 60% by mass based on a total amount of the toner.

Assignments (2)
CHANGE OF NAME Recorded Aug 12, 2021
From: FUJI XEROX CO., LTD.
To: FUJIFILM BUSINESS INNOVATION CORP.
Reel/Frame 058287/0056 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 1, 2011
From: SUGITATE, ATSUSHI
To: FUJI XEROX CO., LTD.
Reel/Frame 026848/0342 →