Electro-optic assemblies and materials for use therein

Patent metadata

Field	Value
Publication number	US-12130533-B2
Application number	US-202318225216-A
Country	US
Kind code	B2
Filing date	Jul 24, 2023
Priority date	Nov 16, 2018
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

An electro-optic medium including an encapsulated material and a binder, the encapsulated material being configured to switch optical states upon application of an electric field, and the binder including a polymer having a plurality of side chains, wherein at least a portion of the side chains have an ionic moiety.

First claim

We claim:

1. An electro-optic medium comprising an encapsulated material and a binder,
the encapsulated material comprising capsules having capsule walls, each capsule wall surrounding an internal phase of the electro-optic medium, the internal phase of the electro-optic medium containing a plurality of electrically charged pigment particles in a suspending fluid, the encapsulated material being configured to switch optical states upon application of an electric field, and
the binder comprising a polymer having a plurality of side chains, wherein at least a portion of the side chains comprise an ionic moiety.

2. The electro-optic medium of claim 1 , wherein the plurality of electrically charged particles comprises at least two differently colored particles.

3. The electro-optic medium of claim 2 , wherein the color of the differently colored particles are selected from the group consisting of red, green, blue, cyan, magenta, yellow, black, and white.

4. The electro-optic medium according to claim 1 , wherein the weight ratio of capsules to binder is from 4:1 to 50:1.

5. The electro-optic medium according to claim 1 , wherein the capsules comprise gelatin.

6. The electro-optic medium of claim 1 , wherein the ionic moiety is anionic or cationic.

7. The electro-optic medium of claim 1 , wherein the ionic moiety is zwitterionic.

8. The electro-optic medium of claim 1 , wherein the polymer has a conductivity of 10 −10 to 10 −1 S/cm.

9. The electro-optic medium of claim 1 , wherein the polymer has a conductivity of 10 −6 to 10 −7 S/cm.

10. The electro-optic medium of claim 1 , wherein 5 to 100% of the side chains comprise an ionic moiety.

11. The electro-optic medium of claim 1 , wherein 15 to 60% of the side chains comprise an ionic moiety.

12. The electro-optic medium of claim 1 , wherein 25 to 45% of the side chains comprise an ionic moiety.

13. The electro-optic medium of claim 1 , wherein the polymer has a number average molecular weight of at least 20,000 g/mol.

14. The electro-optic medium of claim 1 , wherein the polymer has a number average molecular weight of 100,000 to 1,000,000 g/mol.

15. The electro-optic medium of claim 1 , wherein the polymer is a linear or branched polymer.

16. The electro-optic medium of claim 1 , wherein the polymer has a polymeric backbone derived from one or more polymers selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl acetate, polyacrylates, polymethacrylates, polyurethanes, polysaccharides, polyolefins, polyethers, polyesters, polypeptides, proteins, and combinations thereof.

17. The electro-optic medium of claim 1 , wherein the side chains are derived from one or more compounds selected from the group consisting of sulfonic acids, phosphonic acids, quaternary amines, pyridines, imidazoles, carboxylic acids, and salts and combinations thereof.

18. An electro-optic film comprising, in order, a light-transmissive substrate, a layer of light-transmissive conductive material, and a layer of electro-optic medium according to claim 1 .

19. An electro-optic display comprising in order, a light-transmissive substrate, a layer of light-transmissive conductive material, a layer of electro-optic medium according to claim 1 , and a rear substrate.

20. The electro-optic display of claim 19 , wherein the rear substrate comprises a plurality of electrodes.

Assignees

• E Ink Corp

Inventors

• Mccullough Lynne A
• Anseth Jay William

Classifications

• G02F1/1675

  Constructional details · CPC title

• G02F2001/1678

  characterised by the composition or particle type · CPC title

• G02F1/167 Primary

  by electrophoresis · CPC title