Electrochromic materials with enhanced ultraviolet stability and devices comprising same

• US 6,362,914 B2
• Filed: 02/27/2001
• Issued: 03/26/2002
• Est. Priority Date: 08/02/1999
• Status: Expired due to Term

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Guarr, Thomas F., Theiste, David A., Baumann, Kelvin L.
• Primary Examiner(s): Ben, Loha
• Application Number:
  US09/794,512
• Publication Number:
  US 20020012155A1
• Time in Patent Office: 392 Days
• Field of Search: 359/265, 359/270, 359/271, 359/273, 359/275, 359/272, 252/582, 252/583, 544/347, 546/257, 525/540
• US Class Current: 359/265
• CPC Class Codes: C09K 9/02 Organic tenebrescent materials
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions

Abstract

Electrochromic devices and materials having enhanced daylight stability are described. The materials have a redox center linked to an energy receptor site that may serve to dissipate excited state energy from the redox center, alternatively the receptor site may absorb harmful radiation prior to the absorption by the redox center.

Claims

1. An electrochromic device, comprising:

(a) at least one substantially transparent substrate having an electrically conductive material associated therewith;

(b) an electrochromic medium which comprises;

(1) a solvent;

(2) a cathodic electroactive material; and

(3) an anodic electroactive material, wherein at least one of the anodic and cathodic electroactive materials is electrochromic, and further wherein at least one of the anodic and cathodic electroactive materials is at least partially dissolved in the solvent; and

(c) wherein at least one of the anodic and cathodic materials is linked by a bridging unit to an energy receptor site.

2. The electrochromic device according to claim 1, wherein the energy receptor site is capable of accepting excited state energy from a redox center of the electrochromic material or energy from outside of the electrochromic material.

3. The electrochromic device according to claim 1, wherein the cathodic electroactive material comprises a viologen.

4. The electrochromic device according to claim 1, wherein the cathodic electroactive material is selected from at least one of the group comprising:

wherein R₁ is independently selected from alkyl C₁ to C₂₀, alkynl C₂ to C₂₀, and aryl C₅ to C₂₀; and

may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, and additionally may function as a bridge to an energy receptor site;

wherein R₂ is independently selected from alkyl C₁ to C₁₀, alkyl C₂ to C₁₀, aryl C₅ to C₂₀, and may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional groups, and additionally may function as a bridge to an energy receptor site;

wherein R₃ is independently selected from alkyl C₁ to C₅ or an ethyl, propyl or ethylene bridge;

wherein n=0-4 and wherein m=0-2.

5. The electrochromic device according to claim 4, wherein the cathodic electroactive material comprises:

6. The electrochromic device according to claim 1, wherein the anodic electroactive material comprises an azine group containing compound.

7. The electrochromic device according to claim 1, wherein the anodic electroactive material is selected from at least one of the group comprising:

wherein X and Y are independently selected from N, NR₁, S, and O;

wherein R₁ independently is selected from alkyl C₁ to C₂₀, alkynl C₂ to C₂₀, and aryl C₅ to C₂₀; and

may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, etc, and additionally may function as a bridge to an energy receptor site;

wherein R₂ is independently selected from alkyl C₁ to C₁₀, alkyl C₂ to C₁₀, aryl C₅ to C₂₀,and may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, and additionally may function as a bridge to an energy receptor site;

wherein n=0-4; and

wherein m=0-2.

8. The electrochromic device according to claim 7, wherein the anodic electroactive material comprises:

9. The electrochromic device according to claim 1, wherein energy receptor site is selected from at least one of the group comprising:

wherein R₁ is independently selected from alkly C₁ to C₂₀, alkynl C₂ to C₂₀, and aryl C₅ to C₂₀; and

may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, and additionally may function as a bridge to an energy receptor site;

wherein n=0-4; and

wherein k=0-5.

10. The electrochromic device according to claim 1, wherein energy receptor site is selected from at least one of the group comprising 2-hydroxybenzotriazoles, diphenylcyanoacrylates, 2-hyrdoxybenzophenones, and combinations thereof.

11. An electrochromic device, comprising:

(a) a first substantially transparent substrate having an electrically conductive material associated therewith;

(b) a second substantially transparent substrate having an electrically conductive material associated therewith,

(c) an electrochromic medium contained within a chamber positioned between the first and second substrates which comprises;

(1) a solvent;

(2) a cathodic electroactive material; and

(3) an anodic electroactive material, wherein at least one of the anodic and cathodic electroactive materials is electrochromic, and further wherein at least one of the anodic and cathodic electroactive materials is at least partially dissolved in the solvent; and

(d) wherein at least one of the anodic and cathodic materials is linked by a bridging unit to an energy receptor site.

12. The electrochromic device according to claim 11, wherein the energy receptor site is capable of accepting excited state energy from a redox center of the electrochromic material or energy from outside of the electrochromic material.

13. The electrochromic device according to claim 11, wherein the cathodic electroactive material comprises a viologen.

14. The electrochromic device according to claim 11, wherein the cathodic electroactive material is selected from at least one of the group comprising:

wherein R₁ is independently selected from alkyl C₁ to C₂₀, alkynl C₂ to C₂₀, and aryl C₅ to C₂₀; and

may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, and additionally may function as a bridge to an energy receptor site;

wherein R₂ is independently selected from alkyl C₁ to C₁₀, alkyl C₂ to C₁₀, aryl C₅ to C₂₀, and may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional groups, and additionally may function as a bridge to an energy receptor site;

wherein R₃ is independently selected from alkyl C₁ to C₅ or an ethyl, propyl or ethylene bridge;

wherein n=0-4; and

wherein m=0-2.

15. The electrochromic device according to claim 14, wherein the cathodic electroactive material comprises:

16. The electrochromic device according to claim 11, wherein the anodic electroactive material comprises an azine group containing compound.

17. The electrochromic device according to claim 11, wherein the anodic electroactive material is selected from at least one of the group comprising:

wherein X and Y are independently selected from N, NR₁, S, and O;

wherein R₁ is independently selected from alkyl C₁ to C₂₀, alkynl C₂ to C₂₀, and aryl C₅ to C₂₀; and

may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, etc, and additionally may function as a bridge to an energy receptor site;

wherein R₂ is indepenedently selected from alkyl C₁ to C₁₀, alkyl C₂ to C₁₀, aryl C₅ to C₂₀, and may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, and additionally may function as a bridge to an energy receptor site;

wherein n=0-4; and

wherein m=0-2.

18. The electrochromic device according to claim 17, wherein the anodic electroactive material comprises:

19. The electrochromic device according to claim 11, wherein energy receptor site is selected from at least one of the group comprising:

wherein R₁ is independently selected from alkyl C₁ to C₂₀, alkynl C₂ to C₂₀,and aryl C₅ to C₂₀; and

may optionally contain one or more of an ester, ether, aryl, amine, urethane, ammonium, thioester, alkene, and alkyne functional group, and additionally may function as a bridge to an energy receptor site;

wherein n=0-4; and

wherein k=0-5.

20. The electrochromic device according to claim 11, wherein energy receptor site is selected from at least one of the group comprising 2-hydroxybenzotriazoles, diphenylcyanoacrylates, 2-hyrdoxybenzophenones, and combinations thereof.

21. An electrochromic device, comprising:

(a) a first substantially transparent substrate having an electrically conductive material associated therewith;

(b) a second substantially transparent substrate having an electrically conductive material associated therewith,

(c) an electrochromic medium contained within a chamber positioned between the first and second substrates which comprises;

(1) a solvent;

(2) a cathodic electroactive material; and

(3) an anodic electroactive material, wherein at least one of the anodic and cathodic electroactive materials is electrochromic, and further wherein at least one of the anodic and cathodic electroactive materials is at least partially dissolved in the solvent; and

(d) stabilization means associated with the electrochromic device for exhibiting enhanced stability against harmful radiation relative to an electrochromic device without such stabilization means.

22. The electrochromic device according to claim 21, wherein the stabilization means comprises at least one of the anodic and cathodic materials being linked by a bridging unit to an energy receptor site.