IP Library Granted Patent US 8,577,256
Granted Patent B2
US 8,577,256 · App. 13/619,014 · Granted Nov 5, 2013

Electrostatic image developing carrier, electrostatic image developer, process cartridge, image forming method, and image forming apparatus

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Quick Facts
Patent No.
US 8,577,256
App. No.
13/619,014
Granted
Nov 5, 2013
Kind
B2
Abstract

An electrostatic image developing carrier includes a ferrite particle that contains magnesium element in an amount of about 3.0 wt % or more and about 10.0 wt % or less and manganese element in an amount of about 0.2 wt % or more and less than about. 1.0 wt %; and a resin layer that covers the ferrite particle.

Claims (29)

1. A process cartridge attachable to and detachable from an image-forming apparatus, comprising:

an electrostatic image developer; and

at least one selected from the group consisting of an image holding member, a charging unit that charges a surface of an image holding member, a developing unit that develops a latent image formed on a surface of an image holding member with the electrostatic image developer to form a toner image, and a cleaning unit that removes a toner remaining on the surface of the image holding member,

wherein the electrostatic image developer comprises

an electrostatic image developing carrier comprising a ferrite particle that contains metal elements, the metal elements consisting of iron, magnesium, and manganese, the ferrite particle containing the magnesium element in an amount of from 3.0 wt % to 10.0 wt % and the manganese element in an amount of from 0.2 wt % to 1.0 wt %,

a resin layer that covers the ferrite particle, and

a toner.

2. An image-forming method comprising:

charging an image holding member;

exposing the charged image holding member to form an electrostatic latent image on a surface of the image holding member;

developing the electrostatic latent image formed on the surface of the image holding member with an electrostatic image developer to form a toner image;

transferring the toner image formed on the surface of the image holding member to a surface of a transfer-receiving member; and

fixing the toner image,

wherein the electrostatic image developer comprises

an electrostatic image developing carrier comprising a ferrite particle that contains metal elements, the metal elements consisting of iron, magnesium, and manganese, the ferrite particle containing the magnesium element in an amount of from 3.0 wt % to 10.0 wt % and the manganese element in an amount of from 0.2 wt % to 1.0 wt %,

a resin layer that covers the ferrite particle, and

a toner.

3. An image-forming apparatus comprising:

an electrostatic image developer;

an image holding member;

a charging unit that charges the image holding member;

an exposure unit that exposes the charged image holding member to form an electrostatic latent image on the image holding member;

a developing unit that develops the electrostatic latent image with the electrostatic image developer to form a toner image;

a transfer unit that transfers the toner image from the image holding member to a transfer-receiving member; and

a fixing unit that fixes the toner image,

wherein the electrostatic image developer comprises

an electrostatic image developing carrier comprising a ferrite particle that contains metal elements, the metal elements consisting of iron, magnesium, and manganese, the ferrite particle containing the magnesium element in an amount of from 3.0 wt % to 10.0 wt % and the manganese element in an amount of from 0.2 wt % to 1.0 wt %,

a resin layer that covers the ferrite particle, and

a toner.

Assignments (1)
CHANGE OF NAME Recorded Aug 12, 2021
From: FUJI XEROX CO., LTD.
To: FUJIFILM BUSINESS INNOVATION CORP.
Reel/Frame 058287/0056 →