IP Library Granted Patent US 8,828,638
Granted Patent B2
US 8,828,638 · App. 12/568,049 · Granted Sep 9, 2014

Two-component developer, developer cartridge, process cartridge and image formation apparatus

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Quick Facts
Patent No.
US 8,828,638
App. No.
12/568,049
Granted
Sep 9, 2014
Kind
B2
Abstract

A two-component developer including a yellow toner and a carrier, the yellow toner including at least one of C. I. Pigment Yellow 155 or C. I. Pigment Yellow 185, and an azo pigment, the carrier including a first resin, magnetic particles dispersed in the first resin, and elements of Cu, Zn, Ni and Mn each in an amount of from 0 to about 2,000 ppm.

Claims (23)

1. A two-component developer comprising:

a yellow toner; and

a carrier,

the yellow toner comprising at least one of C. I. Pigment Yellow 155 or C. I. Pigment Yellow 185, and an azo pigment, and

the carrier comprising a first resin, magnetic particles dispersed in the first resin, and elements of Mn, Cu, Zn, and Ni each in an amount of 0.1 ppm or more, wherein a total amount of the elements of Mn, Cu, Zn, and Ni in the carrier is 92 ppm or less.

2. The two-component developer according to claim 1 , wherein each of the elements of Cu, Zn, Ni and Mn are present in the carrier in an amount of at least 10 ppm.

3. The two-component developer according to claim 1 , wherein the azo pigment comprises at least one selected from a group consisting of a monoazo pigment, a disazo pigment and an azo lake pigment.

4. The two-component developer according to claim 1 , wherein the azo pigment comprises C. I. Pigment Yellow 74.

5. The two-component developer according to claim 1 , wherein a total amount of the at least one of C. I. Pigment Yellow 155 or C. I. Pigment Yellow 185, and the azo pigment is from about 0.1 parts by weight to about 20 parts by weight, with respect to 100 parts by weight of the yellow toner.

6. The two-component developer according to claim 1 , wherein a content ratio of the at least one of C. I. Pigment Yellow 155 or C. I. Pigment Yellow 185 to the azo pigment is from about 99.5:0.5 to about 5:95.

7. The two-component developer according to claim 1 , wherein the yellow toner further comprises a second resin, the second resin comprising a polycondensation resin.

8. The two-component developer according to claim 7 , wherein a weight average molecular weight of the polycondensation resin is from about 1,500 to about 40,000.

9. The two-component developer according to claim 7 , wherein an acid number of the polycondensation resin is from about 1 mg·KOH/g to about 50 mg·KOH/g.

10. The two-component developer according to claim 7 , wherein the yellow toner comprises the second resin in an amount of from about 10% by weight to about 90% by weight with respect to a total amount of the yellow toner.

11. The two-component developer according to claim 1 , wherein the yellow toner comprises a release agent in an amount of from about 0.5% by weight to about 50% by weight with respect to a total amount of the yellow toner.

12. The two-component developer according to claim 1 , wherein the yellow toner comprises inorganic particles having a primary particle size of from about 5 nm to about 1 μm.

13. The two-component developer according to claim 12 , wherein the inorganic particles have a specific surface area, as measured by a BET method, of from about 20 m 2 /g to about 500 m 2 /g.

14. The two-component developer according to claim 1 , wherein the yellow toner has a volume average particle size of from about 2 μm to about 10 μm.

15. The two-component developer according to claim 1 , wherein the carrier comprises a core material formed from the first resin and the magnetic particles dispersed in the first resin, and a third resin that coats the core material.

16. The two-component developer according to claim 15 , wherein the first resin comprises a crosslinkable resin.

17. The two-component developer according to claim 16 , wherein the crosslinkable resin comprises a phenol resin.

18. The two-component developer according to claim 15 , wherein an amount of the magnetic particles is from about 80% by weight to about 99% by weight with respect to a total amount of the core material.

19. The two-component developer according to claim 15 , wherein an amount of the third resin is from about 1% by weight to about 5% by weight with respect to a total amount of the carrier.

Assignments (1)
CHANGE OF NAME Recorded Aug 12, 2021
From: FUJI XEROX CO., LTD.
To: FUJIFILM BUSINESS INNOVATION CORP.
Reel/Frame 058287/0056 →