Toner compositions including silica blends and method to make the same

Patent metadata

Field	Value
Publication number	US-10606181-B2
Application number	US-201314142373-A
Country	US
Kind code	B2
Filing date	Dec 27, 2013
Priority date	Dec 27, 2013
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

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.

First claim

What is claimed is:

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.

Assignees

• Lexmark Int Inc

Inventors

• Srinivasan Kasturi Rangan
• Jones Rick Owen
• Soale Courtney Harrison
• Vaccaro Strain Devon Jean
• Bejat Ligia Aura

Classifications

• G03G9/09725

  Silicon-oxides; Silicates · CPC title

• G03G9/08711 Primary

  with esters of acrylic or methacrylic acid · CPC title

• G03G9/09708

  Inorganic compounds · CPC title

• G03G9/09716

  treated with organic compounds · CPC title