Granted Patent B2

US 9,217,939 · App. 14/180,411 · Granted Dec 22, 2015

Abstract

Claims (24)

1. A toner composition, comprising:

toner particles;

medium sized fumed silica particles combined with said toner particles having a primary particle size in the range of 30 nm to 60 nm and present in the range of 0.1% to 2.0% wt of the toner composition;

large sized fumed silica particles combined with said toner particles having a primary particle size in the range of 70 nm to about 120 nm, and present in the range of 0.1% to 2% by weight of the toner composition.

2. The toner composition of claim 1 , wherein said medium sized fumed silica particles are treated with a surface treatment selected from the group consisting of hexamethyldisilazane and polydimethylsiloxane.

3. The toner composition of claim 1 , wherein said large sized fumed silica particles are treated with a surface treatment selected from the group consisting of hexamethyldisilazane, polydimethylsiloxane, dimethyldichlorosilane, dimethyldiethoxysilane octyltrialkoxysilane and combinations thereof.

4. The toner composition of claim 1 , wherein the ratio of said medium sized silica to said large sized fumed silica is about 95/5 to about 5/95, more preferably 95/5 to about 50/50.

5. The toner composition of claim 1 , further comprising alumina particles present in the range of 0.01% by 1.0% by weight of the toner composition.

6. The toner composition of claim 5 , wherein said alumina particles are surface treated with octylsilane.

7. The toner composition of claim 1 , further comprising small sized silica particles having a primary particle size in the range of 2 nm to 20 nm present in the range of 0.1% to 0.5% by weight of the toner composition.

8. The toner composition of claim 1 , wherein said toner particles comprise a styrene-acrylate based copolymer resin.

9. The toner composition of claim 1 , wherein said toner particles comprise a polyester based resin.

10. The toner composition of claim 1 , wherein said large sized fumed silica particles are present in the range of 0.25% to 1% by weight of the toner composition.

11. The toner composition of claim 1 , wherein said large sized fumed silica particles are sized 70 nm to 80 nm.

12. A toner composition, comprising:

toner particles;

medium sized silica particles combined with said toner particles having a primary particle size in the range of 30 nm to 60 nm and present in the range of 0.1% 0 to 2.0% wt of the toner composition,

large sized fumed silica particles combined with said toner particles having a primary particle size in the range of 70 nm to about 100 nm and preferably about 70 nm to about 80 nm and present in the range of 0.1% to 2% by weight of the toner composition,

alumina particles surface treated with octylsilane and present in the range of 0.01% by 1.0% by weight of the toner composition,

small sized silica particles having a primary particle size in the range of 2 nm to 20 nm present in the range of 0.1% to 0.5% by weight of the toner composition; and

titania present in the range of about 0.2% to about 1.0% by weight of the toner composition.

13. The toner composition of claim 12 , wherein said medium sized silica particles are treated with a surface treatment selected from the group consisting of hexamethyldisilazane and polydimethylsiloxane.

14. The toner composition of claim 12 , wherein said large sized fumed silica particles are treated with a surface treatment selected from the group consisting of hexamethyldisilazane, polydimethylsiloxane, dimethyldichlorosilane, dimethyldiethoxysilane octyltrialkoxysilane and combinations thereof.

15. The toner composition of claim 12 wherein said titania is acicular titanium oxide.

Assignments (8)