Toner compositions including silica blends and method to make the same
The toner composition of the present invention and method to make the same includes toner particles mixed with a specific set of extra particulate additives including large colloidal silica sized 90 nm to 120 nm and having a conductivity of less than 20 μs/cm in combination with medium size silica particles sized 30 nm to 60 nm. Optionally, additional extra particular additives such as silica sized 2 nm to 20 nm, alumina, titania or mixtures thereof can be used. The finished toner having these specific additives exhibited superior printing performance.
1. 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 to 2.0% wt of the toner composition; and
large sized colloidal silica particles combined with said toner particles having a primary particle size in the range of 90 nm to 120 nm and having a conductivity less than 20μS/cm 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 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 colloidal 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 , further comprising alumina particles present in the range of 0.01% by 1.0% by weight of the toner composition.
5. The toner composition of claim 4 , wherein said alumina particles are surface treated with octylsilane.
6. 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.
7. The toner composition of claim 1 , further comprising the titania particles present in the range of 0.2% to 1.0% by weight.
8. The toner composition of claim 7 , wherein said titania particles are surface treated with aluminum oxide.
9. The toner composition of claim 1 , wherein said toner particles comprise a styrene-acrylate based copolymer resin.
10. The toner composition of claim 1 , wherein said toner particles comprise a polyester based resin.
11. The toner composition of claim 1 , wherein said large sized colloidal silica particles are present in the range of 0.25% to 2% by weight of the toner composition.
12. The toner composition of claim 1 , located in a printer cartridge.
13. A toner composition, comprising:
toner particles combined with a set of extra particular additives including
medium sized silica particles treated with a surface treatment selected from the group consisting of hexamethyldisilazane and polydimethylsiloxane 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 colloidal silica particles having a primary particle size in the range of 90 nm to 120 nm and having a conductivity less than 20μS/cm and present in the range of 0.25% to 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 and present in the range of 0.1% to 0.5% 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; and
titania particles surface treated with aluminum oxide and present in the range of 0.2% to 1.0% by weight of the toner composition.