IP Library › Granted Patent US 7,521,164
Granted Patent B2
US 7,521,164 · App. 12/059,199 · Granted Apr 21, 2009

Toner, and, developer, toner container, process cartridge, image forming apparatus and image forming method

Assignee: Ricoh Company, Ltd.
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Quick Facts
Patent No.
US 7,521,164
App. No.
12/059,199
Granted
Apr 21, 2009
Kind
B2
Abstract

A toner which includes a toner material, wherein the toner satisfies the following formula: 0° C.≦ΔTm≦20° C. where ΔTm represents Tma (° C.)−Tmb (° C.), Tma (° C.) is ½ flown-out temperature of the toner by a capillary type flow tester, and Tmb (° C.) is ½ flown-out temperature of a melt kneaded mixture of the toner by the capillary type flow tester, and wherein Tma is from 130° C. to 200° C.

Claims (11)

1. A toner comprising:

a toner material; and

resin fine particles on a surface of the toner,

wherein the toner has a glass-transition temperature, Tg, of from 30° C. to 46° C., the resin fine particles have a glass-transition temperature, Tg, of from 50° C. to 70° C., and

wherein, when the toner has been masticated with Labo Plastomill, the toner has a ½ flown-out temperature of from 95° C. to 120° C., and before the mastication of the toner, the toner has a ½ flown-out temperature of from 120° C. to 145° C.

2. The toner according to claim 1 , wherein a tetrahydrofuran (THF) insoluble content (gel content) in the toner is from 5% by mass to 25% by mass.

3. The toner according to claim 1 , wherein, in a particle size distribution measured by a flow type particle image measuring apparatus, the content of minute particles having a particle diameter of 2 μm or less is 15% or less.

4. The toner according to claim 1 , wherein, in a distribution of particle diameter measured by a Coulter method, the content of large grains having a particle diameter of 8 μm or more is 2% by mass or less.

5. The toner according to claim 1 , wherein, in a distribution of particle diameter measured by a Coulter method, the content of minute particles having a particle diameter of 3 μm or less is 2% by mass or less.

6. The toner according to claim 1 , wherein the toner has an average circularity of from 0.900 to 0.960 and has a spindle shape.

7. The toner according to claim 1 , wherein the average particle diameter of the resin fine particles is 10 nm to 200 nm.

Priority Claims (2)
JP 2003-325532 · Sep 18, 2003 · national
JP 2004-004424 · Jan 9, 2004 · national
Continuity (3)
Division 1137865300 · Mar 20, 2006
Continuation PCTJP200401355900 · Sep 16, 2004
Related Publication 20080268366A1 · Oct 30, 2008