IP Library Granted Patent US 8,563,205
Granted Patent B2
US 8,563,205 · App. 13/224,969 · Granted Oct 22, 2013

Magenta toner, developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 8,563,205
App. No.
13/224,969
Granted
Oct 22, 2013
Kind
B2
Abstract

Provided is a magenta toner containing toner particles that contain a colorant and a binder resin, wherein the colorant contains C.I. Pigment Red 57:1 and C.I. Pigment Yellow 180, a mass ratio between the C.I. Pigment Red 57:1 and the C.I. Pigment Yellow 180 being 99:1 to 10000:1, and wherein the binder resin contains a polyester resin that has a repeating unit derived from bisphenol A ethylene oxide represented by formula (1): wherein each of m and n independently represents an integer of 2 to 4.

Claims (31)

1. A magenta toner comprising toner particles that contain a colorant and a binder resin,

wherein the colorant contains C.I. Pigment Red 57:1 and C.I. Pigment Yellow 180, a mass ratio between the C.I. Pigment Red 57:1 and the C.I. Pigment Yellow 180 being about 99:1 to about 10000:1, and

wherein the binder resin contains a polyester resin that has a repeating unit derived from bisphenol A ethylene oxide represented by the following formula (1):

wherein each of m and n independently represents an integer of from 2 to 4.

2. The magenta toner according to claim 1 , wherein a volume average particle size of the magenta toner is from about 8 μm to about 15 μm.

3. The magenta toner according to claim 1 , wherein a shape coefficient SF1 of the magenta toner is from about 140 to about 160.

4. The magenta toner according to claim 1 , wherein the toner particles contain a hydrocarbon-based wax as a release agent.

5. The magenta toner according to claim 1 , wherein a glass transition temperature of the magenta toner is from about 35° C. to about 50° C.

6. The magenta toner according to claim 1 , wherein the toner particles are obtained by pulverizing a kneaded material after the kneaded material is obtained by kneading a toner forming material that contains the colorant and the binder resin.

7. The magenta toner according to claim 1 , wherein a mass ratio between the C.I. Pigment Red 57:1 and the C.I. Pigment Yellow 180 is about 500:1 to about 5000:1.

8. The magenta toner according to claim 1 , wherein a proportion of the repeating unit derived from bisphenol A ethylene oxide represented by formula (1) accounting for all the repeating units derived from diol in the binder resin is about 80 mol % or more.

9. A developer comprising the magenta toner according to claim 1 .

10. The developer according to claim 9 , wherein the glass transition temperature of the magenta toner is from about 35° C. to about 50° C.

11. The developer according to claim 9 , wherein the magenta toner particles are obtained by pulverizing a kneaded material after the kneaded material is obtained by kneading the toner forming material that contains the colorant and the binder resin.

12. The developer according to claim 9 , wherein a mass ratio between the C.I. Pigment Red 57:1 and the C.I. Pigment Yellow 180 in the magenta toner is 500:1 to 5000:1.

13. The developer according to claim 9 , wherein a proportion of the repeating unit derived from bisphenol A ethylene oxide represented by formula (1) accounting for all the repeating units derived from diol in the binder resin in the magenta toner is about 80 mol % or more.

14. A toner cartridge containing the magenta toner according to claim 1 and being detachable from an image forming apparatus.

15. A process cartridge containing the developer according to claim 9 , comprising a developing unit developing an electrostatic latent image formed on the surface of a latent image holding member by using the developer to form a toner image, and being detachable from an image forming apparatus.

16. An image forming apparatus comprising:

a latent image holding member;

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

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

a developing unit that develops the electrostatic latent image by using the developer according to claim 9 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.

17. An image forming method comprising:

developing an electrostatic latent image by using a plurality of types of toners to form a plurality of toner images by the plurality of types of toners;

transferring the plurality of toner images by superimposing the images on the surface of the recording medium to form a superimposed multicolor toner image formed of a plurality of layers; and

fixing the superimposed toner image to form an image,

wherein the plurality of types of toners contain at least the magenta toner according to claim 1 and a cyan toner containing a phthalocyanine-based pigment as a colorant.

18. The magenta toner according to claim 1 , wherein a content of the colorant is from 1-20 parts by mass based on 100 parts by mass of the binder resin.

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 2, 2011
From: IWAZAKI, EISUKE; SAKAMOTO, SHINYA; MURAKAMI, TSUYOSHI; YOSHIDA, SATOSHI; INOUE, SATOSHI
To: FUJI XEROX CO., LTD.
Reel/Frame 026856/0828 →