IP Library Granted Patent US 8,679,721
Granted Patent B2
US 8,679,721 · App. 13/113,142 · Granted Mar 25, 2014

Electrostatic charge image developing toner, electrostatic charge image developer, and image forming apparatus

Inventor: Seiji Kikushima (Osaka, JP)
Assignee: Kyocera Mita Corporation
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Quick Facts
Patent No.
US 8,679,721
App. No.
13/113,142
Granted
Mar 25, 2014
Kind
B2
Abstract

The present disclosure aims to provide a toner that is capable of keeping a photoreceptor drum in satisfactory condition for a long period of time and preventing the occurrence of pinholes on the photoreceptor drum, which plays a key role in forming images. The present disclosure provides an electrostatic charge image developing toner in which an external additive is added to toner base particles, wherein the external additive includes inorganic fine particles attached with conductive fine particles, and the conductive fine particles are attached to the inorganic fine particles with certain strength.

Claims (13)

1. An image forming method comprising:

using a charging device to impart a predetermined potential to a circumferential surface of a photoreceptor drum,

using an exposure device to form an electrostatic latent image on the circumferential surface of the photoreceptor drum,

using a developing device and a toner to develop the electrostatic latent image on the circumferential surface of the photoreceptor drum, and to thereby form a toner image on the circumferential surface of the photoreceptor drum,

using a transfer device to transfer the toner image formed on the photoreceptor drum to a sheet,

using a cleaning device to remove from the photoreceptor drum residual toner that remains on the circumferential surface of the photoreceptor drum after transferring the toner image to the sheet, wherein

the toner is an electrostatic charge image developing toner in which an external additive is added to toner base particles, wherein

the external additive comprises inorganic fine particles attached with conductive fine particles, and

the conductive fine particles are attached to the inorganic fine particles such that an existence ratio of the conductive fine particles in a non-transferred toner (conductive fine particles/non-transferred toner) is 9.5 to 30 times an existence ratio of the conductive fine particles in an initial toner (conductive fine particles/initial toner), the non-transferred toner being a toner that remains on a surface of a photoreceptor after the toner image is transferred.

2. The image forming method according to claim 1 , wherein the conductive fine particles are conductive oxide fine particles.

3. The image forming method according to claim 2 , wherein the conductive oxide fine particles are tin oxide conductive fine particles or zinc oxide conductive fine particles.

4. The image forming method according to claim 1 , wherein a primary particle diameter of the conductive fine particles is 5 to 30 nm.

5. The image forming method according to claim 1 , which is used in an image forming apparatus that has a photoreceptor drum using an amorphous silicon photoreceptor.

Assignments (2)
CHANGE OF NAME Recorded May 18, 2012
From: KYOCERA MITA CORPORATION
To: KYOCERA DOCUMENT SOLUTIONS INC.
Reel/Frame 028230/0368 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 23, 2011
From: KIKUSHIMA, SEIJI
To: KYOCERA MITA CORPORATION
Reel/Frame 026321/0082 →
Priority Claims (2)
JP 2010-121642 · May 27, 2010 · national
JP 2011-068663 · Mar 25, 2011 · national
Continuity (1)
Related Publication 20110294057A1 · Dec 1, 2011