IP Library Granted Patent US 8,431,300
Granted Patent B2
US 8,431,300 · App. 12/906,172 · Granted Apr 30, 2013

Toner for electrophotography and developer

Inventor: Koji Kuramashi (Osaka, JP)
Assignee: Kyocera Mita Corporation
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Quick Facts
Patent No.
US 8,431,300
App. No.
12/906,172
Granted
Apr 30, 2013
Kind
B2
Abstract

Toner for electrophotography contains toner base particles containing a binder resin, a colorant, and a wax, resin particles containing a binder resin and a wax, but substantially not containing a colorant, and an external additive that is externally added to the toner base particles and the resin particles, with a mean domain diameter of the wax in the resin particles being larger than a mean domain diameter of the wax in the toner base particles.

Claims (10)

1. Toner for electrophotography, comprising:

toner base particles containing a binder resin, a colorant, and a wax;

resin particles containing a binder resin and a wax, but substantially not containing a colorant; and

an external additive that is externally added to the toner base particles and the resin particles,

wherein a mean domain diameter of the wax in the resin particles is larger than a mean domain diameter of the wax in the toner base particles.

2. Toner for electrophotography according to claim 1 , wherein a content ratio of the wax in the resin particles is higher than a content ratio of the wax in the toner base particles.

3. Toner for electrophotography according to claim 1 , wherein the external additive contains silica particles and titanium oxide particles.

4. Toner for electrophotography according to claim 1 , wherein a content amount of the toner base particles with respect to a total of 100 parts by mass of the toner base particles and the resin particles is 75 to 95 parts by mass.

5. Toner for electrophotography according to claim 1 , wherein a mean domain diameter of the wax in the toner base particles is 0.1 to 2 μm, and a mean domain diameter of the wax in the resin particles is 0.3 to 5 μm.

6. Developer comprising the toner for electrophotography according to claim 1 and carrier.

Assignments (2)
CHANGE OF NAME Recorded May 18, 2012
From: KYOCERA MITA CORPORATION
To: KYOCERA DOCUMENT SOLUTIONS INC.
Reel/Frame 028230/0345 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 18, 2010
From: KURAMASHI, KOJI
To: KYOCERA MITA CORPORATION
Reel/Frame 025149/0363 →
Priority Claims (1)
JP 2009-240144 · Oct 19, 2009 · national
Continuity (1)
Related Publication 20110091800A1 · Apr 21, 2011