Electrochromic devices with improved processability and methods of preparing the same

• US 5,780,160 A
• Filed: 10/26/1994
• Issued: 07/14/1998
• Est. Priority Date: 10/26/1994
• Status: Expired due to Fees

• Current Assignee: Donnelly Corporation (Magna International Incorporated)
• Original Assignee: Donnelly Corporation (Magna International Incorporated)
• Inventors: Agrawal, Anoop, Allemand, Pierre-Marc, Grimes, F. Randall, Bigelow, Barbara A.
• Primary Examiner(s): Speer, Timothy M.
• Application Number:
  US08/330,090
• Time in Patent Office: 1,357 Days
• Field of Search: 359/265, 359/270, 359/272, 359/275, 428/430, 428/432, 428/690, 428/426, 428/441, 252/582, 252/583, 252/586
• US Class Current: 428/426
• CPC Class Codes: G02F 1/15165 Polymers
• CPC Class Codes: Y10T 428/31616 Next to polyester [e.g., alkyd]
• CPC Class Codes: Y10T 428/31645 Next to addition polymer from unsaturated monomers

Abstract

Electrochromic devices and processes for preparing the same are provided which do not require a separate process step of ion intercalation by employing an electrochromically-inert reducing or oxidizing additive in the electrochemically active material or the electrolyte of the electrochromic devices.

Claims

1. An electrochromic device comprising two opposed conducting electrodes, at least one of which is transparent, an electrochemically active layer disposed on an opposing face of one of said electrodes and an electrolyte disposed between said electrochemically active layer and an other opposing face of said electrodes, wherein said electrolyte contains an electrochromically-inert additive selected from the group consisting of reducing agents and oxidizing agents in an effective amount to reduce or oxidize an electrochemically active material in said electrochemically active layer, wherein the reducing agents are selected from the group consisting of oxalic acid, ascorbic acid, mercaptans, hydrazines, amines, organo lithium and mixtures thereof and the oxidizing agents are selected from the group consisting of persulfates, peroxides, nitrosonium salts and mixtures thereof.

2. The electrochromic device according to claim 1, further comprising a first substrate disposed on an outwardly facing surface of one of said electrodes and a second substrate disposed on an other outwardly facing surface of said electrodes, wherein at least one of said substrates is transparent.

3. The electrochromic device according to claim 2, wherein one of said substrates is reflective.

4. The electrochromic device according to claim 2, wherein said device is a vehicular mirror or a vehicular glazing.

5. The electrochromic device according to claim 4, wherein said vehicular mirror is an interior vehicular mirror or an exterior vehicular mirror.

6. The electrochromic device according to claim 5, wherein said interior vehicular mirror is a rearview mirror.

7. The electrochromic device according to claim 4, wherein said vehicular glazing is selected from the group consisting of a vehicular window, a sun roof, sunvisor and a shadeband.

8. The electrochromic device according to claim 1, wherein the electrochromically-inert additive is at least one reducing agent.

9. The electrochromic device according to claim 1, wherein the electrochromically-inert additive is at least one oxidizing agent.

10. The electrochromic device according to claim 1, wherein the electrochemically active layer is comprised of an electrochemically active polymeric material.

11. The electrochromic device according to claim 10, wherein the electrochemically active polymeric material is selected from the group consisting of polyaniline, a polyaniline derivative and mixtures thereof.

12. The electrochromic device according to claim 10, wherein the electrochemically active polymeric material is selected from the group consisting of a copolymer, a blend and a composite.

13. The electrochromic device according to claim 1, wherein the electrochemically active layer is electrochromic.

14. The electrochromic device according to claim 1, further comprising a second electrochemically active layer disposed on the other opposing face of said electrodes.

15. The electrochromic device according to claim 1, wherein the at least one transparent electrode is selected from the group consisting of doped indium oxide, doped tin oxide and doped zinc oxide.

16. The electrochromic device according to claim 1, wherein said electrolyte contains at least one ionic material.

17. The electrochromic device according to claim 1, wherein the electrolyte contains a viologen salt.

18. The electrochromic device according to claim 1, wherein one of said electrodes is reflective.

19. The electrochromic device according to claim 1, wherein the electrochemically active layer contains a component selected from the group consisting of UV stabilizers, heat stabilizers and mixtures thereof.

20. The electrochromic device according to claim 1, wherein the electrolyte contains a component selected from the group consisting of UV stabilizers, adhesion promoting agents, heat stabilizers and mixtures thereof.

21. The electrochromic device according to claim 1, wherein the electrolyte is comprised of a mixture of at least two solvents.

22. The electrochromic device according to claim 1, wherein the electrolyte contains a passive visible or infrared dye.

23. The electrochromic device according to claim 1, wherein the electrolyte is comprised of an inert polymeric additive.

24. The electrochromic device according to claim 1, wherein the electrolyte is comprised of a solid polymeric material.

25. The electrochromic device according to claim 1, wherein the electrolyte is comprised of at least one monomer which is polymerizable to a solid after exposure to heat or radiation.