Toner, image forming apparatus, and process cartridge

Patent metadata

Field	Value
Publication number	US-9709911-B2
Application number	US-201514984411-A
Country	US
Kind code	B2
Filing date	Dec 30, 2015
Priority date	Jan 5, 2015
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A toner including a binder resin and a release agent, wherein the toner has a component soluble in a 50% by mass aqueous methanol solution in an amount of 0.10% by mass to 0.60% by mass, and wherein the toner has a flowing-out beginning temperature (Tfb) of 55.0° C. to 100.0° C. as determined by a flowtester method.

First claim

What is claimed is:

1. A toner comprising:
a binder resin comprising a crystalline polyester resin and a noncrystalline polyester resin, said noncrystalline polyester resin being an unmodified aromatic polyester resin prepared by reacting an alcohol component with a carboxylic acid component in a OH/COOH ratio of 1.293 to 1.364, followed by further reaction with 10 parts by mass to 29 parts by mass of benzoic acid to 600 parts by mass of the total of the alcohol component and the carboxylic acid component; and
a release agent,
wherein the toner comprises a soluble component in an amount of 0.10% by mass to 0.60% by mass where the soluble component is a component soluble in a 50% by mass aqueous methanol solution, and
wherein the toner has a flowing-out beginning temperature (Tfb) of 55.0° C. to 100.0° C. as determined by a flowtester method.

2. The toner according to claim 1 , wherein the toner has the flowing-out beginning temperature (Tfb) of 55.0° C. to 85.0° C.

3. The toner according to claim 1 , wherein the toner has the flowing-out beginning temperature (Tfb) of 55.0° C. to 75.0° C.

4. The toner according to claim 1 , wherein the toner comprises an insoluble component in an amount of 15% by mass to 30% by mass where the insoluble component is a component insoluble in ethyl acetate.

5. An image forming apparatus comprising:
an electrostatic latent image bearer;
a charging unit configured to charge a surface of the electrostatic latent image bearer;
an exposure unit configured to expose the surface charged of the electrostatic latent image bearer to light to form an electrostatic latent image;
a developing unit containing the toner of claim 1 and configured to develop the electrostatic latent image with the toner to forma visible image;
a transfer unit configured to transfer the visible image onto a recording medium to form a transferred image; and
a fixing unit configured to fix the transferred image on the recording medium.

6. A process cartridge comprising:
an electrostatic latent image bearer; and
a developing unit containing the toner of Claim I and configured to develop an electrostatic latent image on the electrostatic latent image bearer with the toner,
wherein the process cartridge supports the electrostatic latent image bearer and the developing unit in an integrated stale, and
wherein the process cartridge is detachably mounted to a main body of an image forming apparatus.

7. The toner according to claim 1 , wherein the unmodified aromatic polyester resin has an acid value of 5 KOHmg/g to 30 KOHmg/g and a hydroxyl value of 10 KOHmg/g to 30 KOHmg/g.

Assignees

• Kimura Yoshitsugu
• Inoue Ryota
• Shiba Masana
• Inoue Daisuke
• Murayama Tomoki
• Takahashi Rintaro
• Ricoh Co Ltd

Inventors

• Kimura Yoshitsugu
• Inoue Ryota
• Shiba Masana
• Inoue Daisuke
• Murayama Tomoki
• Takahashi Rintaro

Classifications

• G03G9/0821

  characterised by physical parameters (magnetic parameters G03G9/083) · CPC title

• G03G9/08755 Primary

  Polyesters · CPC title