Flexible and printable electrooptic devices
This invention discloses how electrooptic devices including electrochromic devices that can be fabricated as tags or labels; and further the materials used, device structures and how these can be processed by printing technologies and on flexible substrates. In addition, systems using displays of such devices and their integration with other components are described for forming labels and tags, etc, that may be actuated wirelessly or powered with low voltage and low capacity batteries.
1. An electrochromic (EC) device comprising a pair of conducting electrodes and an electrolyte disposed between the pair of conducting electrodes, wherein
(a) one of the said electrodes is transparent; and
(b) the said device comprises a redox material which is a colorless monomer or a faintly colored monomer that polymerizes and causes an irreversible change in the color of the said device when the said device is initially electrically activated.
2. An electrochromic (EC) device as in claim 1 used for a display or an indicator.
3. An electrochromic (EC) device as in claim 2 where the device is formed by printing at least one of the electrodes or the electrolyte.
4. An electrochromic (EC) device as in claim 1 , where the said monomer polymerizes to form a polymer when the device is activated by applying a voltage across the conducting electrodes, and the said polymer causes a color change in the device.
5. An electrochromic (EC) device as in claim 1 wherein the electrolyte in the device further comprises of a second redox material that is complimentary to the said redox monomer.
6. An electrochromic (EC) device as in claim 5 wherein the electrolyte in the said device comprises the said monomer.
7. An electrochromic (EC) device as in claim 5 , where the said monomer polymerizes to form a polymer when the device is activated by applying a voltage across the conducting electrodes, and the said polymer causes a color change in the device.
8. An electrochromic (EC) device comprises a pair of conducting electrodes and an electrolyte in contact with the pair of said conducting electrodes, wherein
(a)
the said electrolyte comprises a redox material which is a colorless monomer or a faintly colored monomer that polymerizes and deposits as a layer on one of the said electrodes which causes a change in the color of the said device when the said device is initially electrically activated.
9. An electrochromic (EC) device as in claim 8 , where the said monomer polymerizes to form a polymer when the device is activated by applying a voltage across the conducting electrodes, and the said polymer causes a color change in the device.
10. An electrochromic device as in claim 9 , wherein the color change is irreversible.
11. An electrochromic device as in claim 8 , wherein the said opposing electrodes are in an interdigited pattern formed on one of the surfaces of a substrate.
12. An electrochromic device as in claim 11 , wherein the conductive electrodes are formed on the said substrate by printing the said electrodes in the desired pattern or etching a conductive coating to form the electrodes in the desired pattern.
13. An electrochromic device as in claim 11 , wherein the substrate is a flexible transparent polymer.
14. An electrochromic device as in claim 11 , wherein the electrolyte is a solid material.
15. An electrochromic device as in claim 14 , wherein the electrolyte is deposited by a printing process.
16. An electrochromic device as in claim 11 , wherein the electrolyte is protected from the environment using an additional layer.
17. An electrochromic device as in claim 8 , wherein the two opposing conductive electrodes are deposed in an interdigited pattern, and the electrolyte is deposited to contact the said electrodes, and when the said device is activated by applying a potential across the said electrodes it results in an appearance change which is not reversible.
18. An electrochromic device as in claim 8 , which is part of a display system, wherein such display system is capable of wireless communication.
19. An electrochromic device as in claim 8 , wherein the electrolyte is a solid material.
20. An electrochromic device as in claim 8 which is a part of a display system, wherein such system is located on a flexible substrate.
21. An electrochromic device as in claim 8 comprising a second redox material.
22. An electrochromic device as in claim 21 wherein the second redox material is in the electrolyte.
23. A display system comprising an electrochromic (EC) device, wherein the said electrochromic device comprises (a) a redox monomer (a) and upon initial electrical activation of the said device, the said monomer polymerizes resulting in an irreversible optical change so as to result in a change of information being displayed.
24. A display system as in claim 23 wherein the EC device activation is irreversible.
25. A display system as in claim 23 wherein the said system is formed on a flexible substrate.