Charge adjuvants in electrostatic inks

• US 20080163789A1
• Filed: 01/09/2007
• Published: 07/10/2008
• Est. Priority Date: 01/09/2007
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Katz, Gregory, Teishev, Albert, Israeli, Yaffa, Silcoff, Elliad
• Granted Patent: US 7,736,829 B2
• Time in Patent Office: Days
• US Class Current: 106/31.6
• CPC Class Codes: G03G 9/135 characterised by stabiliser or charge-controlling agents
• CPC Class Codes: G03G 9/1355 Ionic, organic compounds

Abstract

Ink toners, electroink compositions, methods of making ink toners, methods of making electroink compositions, and the like, are described.

Claims

1. An ink toner, comprising:

a charge adjuvant, a carrier liquid, a resin, a pigment, and a charge director, wherein the charge adjuvant is a metal alkoxylate compound, and wherein the ink toner does not include aluminum stearate.

3. The ink toner of claim 1, wherein metal alkoxylate compound is about 0.05 to 4% by total weight of the ink solids.

4. The ink toner of claim 1, wherein ink toner has a viscosity of about 20 to 600.

5. The ink toner of claim 1, wherein the metal alkoxylate compound is aluminum monostearate monobenzoate hydroxide.

6. The ink toner of claim 5, wherein aluminum monostearate monobenzoate hydroxide is about 0.05 to 4% by total weight of the ink solids.

7. The ink toner of claim 5, wherein aluminum monostearate monobenzoate hydroxide is about 0.125 to 4% by total weight of the ink solids.

8. The ink toner of claim 1, wherein the electrostatic ink has a low field conductivity of about 4 to 300.

2. The ink toner, wherein the metal alkoxylate compound is a compound having a formula selected from formula I, formula II, and formula III:

9. A method of making an electrostatic ink, comprising:

grinding a carrier liquid, a resin, and a pigment, to form a slurry;

mixing a charge adjuvant and a charge director with the slurry after grinding, wherein the charge adjuvant is a metal alkoxylate compound, and wherein the ink toner does not include aluminum stearate; and

forming the electrostatic ink.

10. The method of claim 9, wherein mixing includes:

mixing the charge adjuvant with the slurry homogeneously prior to mixing the charge director with the ink slurry.

11. The method of claim 9, wherein mixing includes:

mixing the charge director and the charge adjuvant simultaneously to the ink slurry.

12. The method of claim 9, wherein mixing includes:

mixing the charge director prior to adding the charge adjuvant to the ink slurry.

13. The method of claim 9, wherein the metal alkoxylate compound is a compound having a formula selected from formula I, formula II, and formula III:

14. The method of claim 9, wherein the metal alkoxylate compound is aluminum monostearate monobenzoate hydroxide.

15. The method of claim 9, wherein the charge adjuvant added to the to the ink slurry at multiple times during the preparation of the electrostatic ink.

16. The method of claim 9, further comprising:

adding the charge adjuvant to change a characteristic selected from;

viscosity of the electrostatic ink, conductivity of the electrostatic ink, and combinations thereof, wherein the addition of the charge adjuvant does not change the particle shape or the morphology of the electrostatic ink.

17. A method of making an electrostatic ink, comprising:

grinding a charge adjuvant, a carrier liquid, a resin, a pigment, and a charge director together to form an ink toner, wherein the charge adjuvant is a metal alkoxylate compound, and wherein the ink toner does not include aluminum stearate; and

forming the electrostatic ink.

18. The method of claim 17, wherein the metal alkoxylate compound is a compound having a formula selected from formula I, formula II, and formula III:

19. The method of claim 17, wherein the metal alkoxylate compound is aluminum monostearate monobenzoate hydroxide.