Electronic inks

Patent metadata

Field	Value
Publication number	US-10007166-B2
Application number	US-201314901995-A
Country	US
Kind code	B2
Filing date	Aug 30, 2013
Priority date	Aug 30, 2013
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

Electronic inks are disclosed herein. An example of the electronic ink includes a non-polar carrier fluid, a colorant particle dispersion, and a charge director. The colorant particle dispersion includes another non-polar carrier fluid (which may be the same as, or different from the non-polar carrier fluid), colorant particles, and chargeable dispersant molecules bonded to the colorant particles. The charge director is to charge the chargeable dispersant molecules.

First claim

What is claimed is:

1. An electronic ink, comprising:
a non-polar carrier fluid;
a first colorant particle dispersion, including:
another non-polar carrier fluid, the other non-polar carrier fluid being the same as, or different from the non-polar carrier fluid;
first colorant particles; and
first chargeable dispersant molecules bonded to the colorant particles, wherein the first colorant particle dispersion exhibits a first color, and wherein each of the first chargeable dispersant molecules includes:
a central chromophore;
a chargeable pendant group bonded to the central chromophore; and
a steric stabilization pendant group bonded to the central chromophore, wherein the steric stabilization pendant group has a structure

 and wherein y ranges from 0.58 to 2.8 and n ranges from 10 to 20;

a charge director to charge the first chargeable dispersant molecules;
a second colorant particle dispersion, including:
the non-polar carrier fluid or the other non-polar carrier fluid;
second colorant particles; and
second chargeable dispersant molecules bonded to the second colorant particles, wherein the second colorant particle dispersion exhibits a second color that is different than the first color.

2. The electronic ink as defined in claim 1 wherein the ink is substantially free of unattached chargeable dispersant molecules.

3. The electronic ink as defined in claim 1 wherein the charge director is chosen from polyisobutylene succinimide; polyhydroxystearic amide salt; butanedioic acid, 2-sulfo-, 1,4-tridecyl ester, barium salt with barium hydrogen phosphate; sodium di-2-ethylhexylsulfosuccinate, dioctyl sulfosuccinate, lecithin, and combinations thereof.

4. An electronic ink, comprising:
a non-polar carrier fluid;
a colorant particle dispersion, including:
another non-polar carrier fluid, the other non-polar carrier fluid being the same as, or different from the non-polar carrier fluid;
colorant particles; and
chargeable dispersant molecules bonded to the colorant particles; and

a charge director to charge the chargeable dispersant molecules;
wherein each of the chargeable dispersant molecules includes:
a central chromophore;
a chargeable pendant group bonded to the central chromophore; and
a steric stabilization pendant group bonded to the central chromophore,

wherein the steric stabilization pendant group has a structure

 and wherein y ranges from 0.58 to 2.8 and n ranges from 10 to 20.

5. The electronic ink as defined in claim 1 wherein each of the non-polar carrier fluid and the other non-polar carrier fluid is independently chosen from hydrocarbons, halogenated or partially halogenated hydrocarbons, functionalized hydrocarbons, oxygenated fluids, siloxanes, silicone oils, organic solvents, natural oils, and combinations thereof.

6. The electronic ink as defined in claim 1 wherein the chargeable pendant group is selected from the group consisting of a carboxylic acid-containing pendant group, a sulfonic acid-containing pendant group, and combinations thereof.

7. The electronic ink as defined in claim 1 wherein:
the first chargeable dispersant molecules are positively charged; and
the second chargeable dispersant molecules are negatively charged.

8. The electronic ink as defined in claim 1 wherein:
the first chargeable dispersant molecules are positively charged; and
the second chargeable dispersant molecules are positively charged.

9. The electronic ink as defined in claim 1 , further comprising an oligomeric additive present in an amount of up to 80 wt. % of a total wt. % of the electronic ink.

10. The electronic ink as defined in claim 1 wherein:
the first chargeable dispersant molecules are negatively charged; and
the second chargeable dispersant molecules are negatively charged.

11. A method for making an electronic ink, the method comprising:
selecting a first colorant particle dispersion, including:
a non-polar carrier fluid;
first colorant particles; and
first chargeable dispersant molecules bonded to the colorant particles, wherein the first colorant particle dispersion exhibits a first color, and wherein each of the first chargeable dispersant molecules includes:
a central chromophore;
a chargeable pendant group bonded to the central chromophore; and
a steric stabilization pendant group bonded to the central chromophore, wherein the steric stabilization pendant group has a structure

 and wherein y ranges from 0.58 to 2.8 and n ranges from 10 to 20;

selecting a second colorant particle dispersion, including:
the non-polar carrier fluid or another non-polar carrier fluid, the other non-polar carrier fluid being the same as or different from the non-polar carrier fluid;
second colorant particles; and
second chargeable dispersant molecules bonded to the second colorant particles, wherein the second colorant particle dispersion exhibits a second color that is different than the first color;

incorporating the selected first colorant particle dispersion and the selected second colorant particle dispersion into additional non-polar carrier fluid, the additional non-polar carrier fluid being the same as or different from the non-polar carrier fluid and the same as or different from the other non-polar carrier fluid; and
adding a charge director to the additional non-polar carrier fluid either before or after the selected first colorant particle dispersion and the selected second colorant particle dispersion are incorporated therein, whereby the charge director imparts a charge or enhances a charge on the first and second chargeable dispersant molecules.

12. The method as defined in claim 11 wherein:
the first colorant particle dispersion is present in an amount ranging from about 5 wt. % to about 80 wt. % of a total wt. % of the electronic ink;
the charge director is present in an amount ranging from about 0.05 wt. % to about 5.0 wt. % of the total wt. % of the electronic ink; and
the additional non-polar carrier fluid and the second colorant particle dispersion make up a balance of the electronic ink.

13. A display element, comprising:
two opposed electrodes defining a viewing area therebetween;
a dielectric layer disposed between the electrodes, the dielectric layer having at least one reservoir defined therein;
an electronic ink disposed in the viewing area, the electronic ink including:
a non-polar carrier fluid;
a first colorant particle dispersion, including:
another non-polar carrier fluid, the other non-polar carrier fluid being the same as, or different from the non-polar carrier fluid;
first colorant particles; and
first chargeable dispersant molecules bonded to the colorant particles, wherein the first colorant particle dispersion exhibits a first color, and wherein each of the first chargeable dispersant molecules includes:
a central chromophore;
a chargeable pendant group bonded to the central chromophore; and
a steric stabilization pendant group bonded to the central chromophore, wherein the steric stabilization pendant group has a structure

Assignees

• Hewlett Packard Development Co

Inventors

• Liu Qin
• Grinwald Yaron
• Combs Gregg

Classifications

• C09D11/52

  Electrically conductive inks · CPC title

• C09D11/03

  characterised by features other than the chemical nature of the binder · CPC title

• G02F2001/1678

  characterised by the composition or particle type · CPC title

• G02F1/167 Primary

  by electrophoresis · CPC title

• G02F1/1675

  Constructional details · CPC title