IP Library › Granted Patent US 10,884,350
Granted Patent B2
US 10,884,350 · App. 16/452,789 · Granted Jan 5, 2021

Toner, toner accommodating unit, and image forming apparatus

Inventors: Toma Takebayashi (Shizuoka, JP); Taichi Nemoto (Shizuoka, JP)
Assignee: Ricoh Company, Ltd.
G03G9/08755G03G9/0825G03G9/08711G03G9/08797G03G15/0865
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Quick Facts
Patent No.
US 10,884,350
App. No.
16/452,789
Granted
Jan 5, 2021
Kind
B2
Abstract

A toner is provided. The toner comprises a binder resin, a colorant, and a release agent. The binder resin comprises a polyester resin comprising a crystalline polyester resin. The crystalline polyester resin forms domains having a number average long diameter of from 0 to 50 nm in a cross-section of the toner. The toner satisfies the following relation: G ′(50)/ G ′(90)≥6.0×10 2 where G′(50) and G′(90) represent storage elastic modulus of the toner at 50 degrees C. and 90 degrees C., respectively.

Claims (47)

1. A toner comprising:

a binder resin comprising a polyester resin comprising a crystalline polyester resin;

a colorant; and

a release agent,

wherein the crystalline polyester resin forms domains having a number average long diameter of from 0 to 50 nm in a cross-section of the toner,

wherein the toner satisfies the following relation:

9.0×10 2 ≥G ′(50)/ G ′(90)≥6.0×10 2

where G′(50) and G′(90) represent storage elastic modulus of the toner at 50 degrees C. and 90 degrees C., respectively,

wherein the binder resin further comprises a styrene acrylic resin, and a proportion of the styrene acrylic resin in the binder resin is less than 10% by mass.

2. The toner according to claim 1 , wherein a proportion of the polyester resin in the binder resin is 90% by mass or more.

3. The toner according to claim 2 , wherein the number average long diameter of the domains of the crystalline polyester resin is from 0 to 10 nm.

4. The toner according to claim 1 , wherein the binder resin further comprises a styrene acrylic resin, and a proportion of the styrene acrylic resin in the binder resin is less than 5% by mass.

5. The toner according to claim 1 , wherein the number average long diameter of the domains of the crystalline polyester resin is from 0 to 10 nm.

6. A toner accommodating unit comprising:

a container; and

the toner according to claim 1 contained in the container.

7. An image forming apparatus comprising:

an electrostatic latent image bearer;

an electrostatic latent image forming device configured to form an electrostatic latent image on the electrostatic latent image bearer; and

a developing device containing the toner according to claim 1 , configured to develop the electrostatic latent image formed on the electrostatic latent image bearer with the toner to form a toner image.

8. The image forming apparatus according to claim 7 , further comprising:

a transfer device configured to transfer the toner image formed on the electrostatic latent image onto a surface of a recording medium; and

a fixing device configured to fix the toner image on the surface of the recording medium.

9. A toner comprising:

a binder resin comprising a polyester resin comprising a crystalline polyester resin;

a colorant; and

a release agent,

wherein the crystalline polyester resin forms domains having a number average long diameter of from 0 to 50 nm in a cross-section of the toner,

wherein the toner satisfies the following relation:

9.0×10 2 ≥G ′(50)/ G ′(90)≥6.0×10 2

where G′(50) and G′(90) represent storage elastic modulus of the toner at 50 degrees C. and 90 degrees C., respectively,

wherein the toner exhibits an endothermic peak indicating an amount of heat absorption of 3 J/g or more in a first temperature rising of differential scanning calorimetry, the endothermic peak derived from the crystalline polyester resin.

10. The toner according to claim 9 , wherein a proportion of the polyester resin in the binder resin is 90% by mass or more.

11. The toner according to claim 10 , wherein the number average long diameter of the domains of the crystalline polyester resin is from 0 to 10 nm.

12. The toner according to claim 9 , wherein the binder resin further comprises a styrene acrylic resin, and a proportion of the styrene acrylic resin in the binder resin is less than 10% by mass.

13. The toner according to claim 9 , wherein the binder resin further comprises a styrene acrylic resin, and a proportion of the styrene acrylic resin in the binder resin is less than 5% by mass.

14. The toner according to claim 9 , wherein the number average long diameter of the domains of the crystalline polyester resin is from 0 to 10 nm.

15. A toner accommodating unit comprising:

a container; and

the toner according to claim 9 contained in the container.

16. An image forming apparatus comprising:

an electrostatic latent image bearer;

an electrostatic latent image forming device configured to form an electrostatic latent image on the electrostatic latent image bearer; and

a developing device containing the toner according to claim 9 , configured to develop the electrostatic latent image formed on the electrostatic latent image bearer with the toner to form a toner image.

17. The image forming apparatus according to claim 16 , further comprising:

a transfer device configured to transfer the toner image formed on the electrostatic latent image onto a surface of a recording medium; and

a fixing device configured to fix the toner image on the surface of the recording medium.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 26, 2019
From: TAKEBAYASHI, TOMA; NEMOTO, TAICHI
To: RICOH COMPANY, LTD.
Reel/Frame 049591/0624 →
Priority Claims (2)
JP 2018-129285 · Jul 6, 2018 · national
JP 2019-103578 · Jun 3, 2019 · national
Continuity (1)
Related Publication 20200012206A1 · Jan 9, 2020
Cited By (1)
US 12,416,872