Toner, developer, and image forming apparatus

Patent metadata

Field	Value
Publication number	US-10670980-B2
Application number	US-201816031490-A
Country	US
Kind code	B2
Filing date	Jul 10, 2018
Priority date	Jan 18, 2016
Publication date	Jun 2, 2020
Grant date	Jun 2, 2020

Abstract

Provided is a toner including a crystalline polyester resin including a constitutional unit derived from saturated aliphatic dicarboxylic acid and a constitutional unit derived from saturated aliphatic diol, an amorphous hybrid resin, an amorphous polyester resin, a release agent, and a colorant, wherein the crystalline polyester resin includes a constitutional unit derived from sebacic acid as the constitutional unit derived from the saturated aliphatic dicarboxylic acid, and the amorphous hybrid resin is a composite resin including a polyester-based resin unit and a styrene-based resin unit.

First claim

What is claimed is:

1. A toner comprising:
a crystalline polyester resin comprising a constitutional unit derived from saturated aliphatic dicarboxylic acid and a constitutional unit derived from saturated aliphatic diol;
an amorphous hybrid resin;
an amorphous polyester resin;
a release agent; and
a colorant,
wherein the crystalline polyester resin comprises a constitutional unit derived from sebacic acid as the constitutional unit derived from the saturated aliphatic dicarboxylic acid,
the amorphous hybrid resin is a composite resin comprising a styrene-based resin unit and a polyester-based resin unit comprising a polyvalent alcohol component,
the styrene-based resin unit of the amorphous hybrid resin comprises a unit derived from at least one selected from the group consisting of 2-ethylhexyl acrylate, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tertiarybutyl acrylate, tertiarybutyl methacrylate, 2-ethylhexyl methacrylate, octyl acrylate, octyl methacrylate, isooctyl acrylate, isooctyl methacrylate, decyl acrylate, decyl methacrylate, isodecyl acrylate, isodecyl methacrylate, stearyl acrylate, stearyl methacrylate, isostearyl acrylate and isostearyl methacrylate,
the polyvalent alcohol component of the polyester-based resin unit of the amorphous hybrid resin is solely derived from a saturated aliphatic diol,
the crystalline polyester resin comprises a constitutional unit derived from straight-chain aliphatic diol having from 2 through 8 carbon atoms as the constitutional unit derived from the saturated aliphatic diol, and
a glass transition temperature (Tg1st) of the toner determined from a DSC curve of first heating as measured by differential scanning calorimetry (DSC) is from 45° C. through 55° C.

2. The toner according to claim 1 ,
wherein SP1, SP2, and SP3 satisfy formulae (1) to (3) below,
SP 1< SP 3< SP 2  Formula (1)

0.4< SP 2 SP 1<1.1  Formula (2)

0.1< SP 3 SP 1<1.0  Formula (3)

where SP1 is an SP value of the crystalline polyester resin, SP2 is an SP value of the amorphous polyester resin, and SP3 is an SP value of the amorphous hybrid resin.

3. A developer comprising:
the toner according to claim 1 .

4. A toner stored unit comprising:
a container; and
the toner according to claim 1 , stored in the container.

5. An image forming apparatus comprising:
an electrostatic latent image-bearer;
an electrostatic latent image-forming unit configured to form an electrostatic latent image on the electrostatic latent image-bearer; and
a developing unit that comprises the toner according to claim 1 and is configured to develop the electrostatic latent image formed on the electrostatic latent image-bearer to form a visible image.

6. An image forming method comprising:
forming an electrostatic latent image on an electrostatic latent image-bearer; and
developing the electrostatic latent image formed on the electrostatic latent image-bearer with the toner according to claim 1 to form a toner image.

7. The toner according to claim 1 ,
wherein the polyvalent alcohol component of the polyester-based resin unit of the amorphous hybrid resin is solely derived from a straight-chain saturated aliphatic diol.

8. The toner according to claim 1 ,
wherein the polyvalent alcohol component of the polyester-based resin unit of the amorphous hybrid resin is solely derived from a linear saturated aliphatic diol having from 2 through 12 carbon atoms.

Assignees

• Ohnuma Koh
• Sugimoto Tsuyoshi
• Nakayama Shinya
• Santo Hideyuki
• Hasegawa Shin
• Karato Suzuka
• Nagata kohsuke
• Ricoh Co Ltd

Inventors

• Ohnuma Koh
• Sugimoto Tsuyoshi
• Nakayama Shinya
• Santo Hideyuki
• Hasegawa Shin
• Karato Suzuka
• Nagata kohsuke

Classifications

• G03G9/08786

  Graft polymers · CPC title

• G03G9/08

  with toner particles · CPC title

• G03G9/08755 Primary

  Polyesters · CPC title

• G03G15/0865

  Arrangements for supplying new developer · CPC title

• G03G9/08795

  characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants · CPC title