Carrier and developer

Patent metadata

Field	Value
Publication number	US-10031434-B2
Application number	US-201615160590-A
Country	US
Kind code	B2
Filing date	May 20, 2016
Priority date	Jun 12, 2015
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A carrier includes a resin layer including Al and Sn and covering the surface of the carrier. A detectable amount of Al is from 1.0% to 12.1% by atom and a ratio (Al/Sn) of the detectable amount of Al to that of Sn is from 2.0 to 50.0 when the carrier is subjected to an X-ray photoelectron spectroscopic (XPS) analysis.

First claim

What is claimed is:

1. A carrier, comprising:
a magnetic core particle, and
a resin layer comprising resin, Al, and Sn and covering a surface of the magnetic core particle,
wherein the carrier has a detectable amount of Al of from 1.0% to 12.1% by atom, and a ratio (Al/Sn) of the detectable amount of Al to a detectable amount of Sn of from 4.3 to 50.0, as determined by X-ray photoelectron spectroscopic (XPS) analysis of said carrier,
wherein the Al in the resin layer is present as Al particles, and a content of the Al particles in the resin layer is from 12% to 76% by mass based on total mass of the resin in the resin layer, and
wherein the Sn present in the resin layer is present as Sn particles.

2. The carrier of claim 1 , wherein said carrier, after being removed from a mixture of said carrier and 20% by mass of a toner based on the total mass of the carrier and the toner prepared by mixing at 500 rpm for 2 hrs at 30° C. and 90% relative humidity, has a detectable amount of Al of from 9.5% to 20.0% by atom as determined by XPS analysis.

3. The carrier of claim 1 , wherein said carrier, after being removed from a mixture of said carrier and 20% by mass of a toner based on the total mass of the carrier and the toner prepared by mixing at 500 rpm for 2 hrs at 30° C. and 90% relative humidity, has a ratio (Al/Sn) of from 5.0 to 11.0 as determined by XPS analysis.

4. The carrier of claim 1 , wherein the content of the Al particles in the resin layer is from 52% to 76% by mass based on total mass of the resin in the resin layer.

5. The carrier of claim 1 , wherein the ratio (Al/Sn) of the detectable amount of Al to the detectable amount of Sn is from 9.2 to 48.7.

6. A developer, comprising;
the carrier according to claim 1 ; and
a toner.

7. An image forming apparatus, comprising:
an electrostatic latent image bearer;
an electrostatic image former to form an electrostatic latent image on the electrostatic latent image bearer; and
an image developer comprising the developer according to claim 6 .

8. A developer container unit containing the developer according to claim 6 .

9. The carrier of claim 1 , wherein the Al particles are aluminum oxide particles.

10. The carrier of claim 9 , wherein the Sn particles are tin oxide particles or particles of tin oxide doped with phosphorus.

11. The carrier of claim 1 , wherein the resin layer has an average thickness of from 0.30 to 0.90 μm.

12. The carrier of claim 1 , wherein the resin is a copolymer comprising the following A component and B component:

wherein R 1 represents a hydrogen atom or a methyl group; m represents an integer of from 1 to 8; R 2 represents an alkyl having 1 to 4 carbon atoms; R 3 represents an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; X is from 10% to 90% by mol; and Y is from 10% to 90% by mol.

13. The carrier of claim 12 , wherein X is from 10% to 40% by mol, and Y is from 10% to 80% by mol.

14. The carrier of claim 12 , wherein the Sn particles are tin oxide particles or particles of tin oxide doped with phosphorus, and the Al particles are aluminum oxide particles.

Assignees

• Takii Mariko
• Murasawa Yoshihiro
• Nakamura Takahiro
• Niwayama Kei
• Murata Haruki
• Taikoji Masato
• Sakata Koichi
• Ricoh Co Ltd

Inventors

• Takii Mariko
• Murasawa Yoshihiro
• Nakamura Takahiro
• Niwayama Kei
• Murata Haruki
• Taikoji Masato
• Sakata Koichi

Classifications

• G03G15/08

  using a solid developer, e.g. powder developer · CPC title

• G03G9/1139 Primary

  Inorganic components of coatings · CPC title

• G03G9/1075

  Structural characteristics of the carrier particles, e.g. shape or crystallographic structure · CPC title

• G03G9/1133

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title