Variable transmission electrochromic window and associated aircraft window system

• US 8,736,943 B2
• Filed: 01/17/2012
• Issued: 05/27/2014
• Est. Priority Date: 01/17/2012
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Guarr, Thomas F., Theiste, David A., Ash, Kevin L., Driscoll, David I., Luten, Henry A.
• Primary Examiner(s): Jones, James
• Application Number:
  US13/351,643
• Publication Number:
  US 20130182308A1
• Time in Patent Office: 861 Days
• Field of Search: 359/273
• US Class Current: 359/273
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions
• CPC Class Codes: G02F 1/1506 caused by electrodeposition, e.g. electrolytic deposition of an inorganic material on or close to an electrode
• CPC Class Codes: G02F 1/15165 Polymers
• CPC Class Codes: G02F 1/1533 structural features not otherwise provided for
• CPC Class Codes: G02F 2001/15145 the electrochromic layer comprises a mixture of anodic and cathodic compounds
• CPC Class Codes: G02F 2001/1518 Ferrocene compounds

Abstract

A variable transmission electrochromic window including: first and second substantially transparent substrates having electrically conductive materials associated therewith; an electrochromic medium contained within a chamber positioned between the first and second substrates which includes at least one solvent, at least one anodic electroactive material, at least one cathodic electroactive material, and wherein at least one of the anodic and cathodic electroactive materials is electrochromic; and wherein the electrochromic window exhibits an E_v of less than approximately 20, and more preferably less than approximately 5, while in a low transmission state during normal daylight conditions.

Claims

1. A variable transmission electrochromic window, comprising:

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

a second substantially transparent substrate having an electrically conductive material associated therewith;

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

at least one solvent;

a first anodic electroactive material;

a second anodic electroactive material;

at least one cathodic electroactive material; and

wherein at least one of the anodic and cathodic electroactive materials is electrochromic; and

wherein the electrochromic window exhibits an E_v of less than approximately 20 while in a low transmission state during normal daylight conditions.

2. The variable transmission electrochromic window according to claim 1, wherein the electrochromic window exhibits an E_v of less than approximately 10 while in a low transmission state during normal daylight conditions.

3. The variable transmission electrochromic window according to claim 1, wherein the electrochromic window exhibits an E_v of less than approximately 5 while in a low transmission state during normal daylight conditions.

4. The variable transmission electrochromic window according to claim 1, wherein the electrochromic medium further comprises at least one of an anodic and cathodic color-stabilizing redox buffer.

5. The variable transmission electrochromic window according to claim 1, wherein the electrochromic medium further comprises anodic and cathodic color-stabilizing redox buffers.

6. The variable transmission electrochromic window according to claim 1, wherein the concentration of the at least one cathodic electroactive material is greater than the combined concentration of the first and second anodic electroactive materials.

7. The variable transmission electrochromic window according to claim 1, wherein the at least one cathodic electroactive material comprises a viologen.

8. The variable transmission electrochromic window according to claim 7, wherein the viologen comprises a 1,1′

-dialkyl-4,4′

-dipyridinium compound and wherein at least one alkyl group attached to the dipyridinium compound comprises at least 4 carbon atoms and includes less than 2 β

hydrogen atoms.

9. The variable transmission electrochromic window according to claim 1, wherein the first anodic electroactive material comprises a phenazine.

10. The variable transmission electrochromic window according to claim 9, wherein the phenazine comprises a 5,10-dialkyl-5,10-dihydrophenazine compound, wherein at least one alkyl group attached to the phenazine compound comprises at least 4 carbon atoms and is void of any β

hydrogen atoms.

11. The variable transmission electrochromic window according to claim 9, wherein the phenazine comprises at least one neopentyl group.

12. The variable transmission electrochromic window according to claim 1, wherein the electrochromic medium further comprises at least one of a cross-linked polymer matrix, a free-standing gel, and a substantially non-weeping gel.

13. The variable transmission electrochromic window according to claim 1, wherein a substrate is less than approximately 1.0 mm thick.

14. The variable transmission electrochromic window according to claim 1, wherein the window comprises an aircraft window.

15. An aircraft window system, comprising:

a housing for containing a first substantially transparent interior substrate, a second substantially transparent exterior substrate, and a variable transmission electrochromic window positioned between the interior and exterior substrates, wherein the variable transmission electrochromic window comprises;

a third substantially transparent substrate having an electrically conductive material associated therewith;

a fourth substantially transparent substrate having an electrically conductive material associated therewith;

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

at least one solvent;

a first anodic electroactive material;

a second anodic electroactive material;

at least one cathodic electroactive material; and

wherein at least one of the anodic and cathodic electroactive materials is electrochromic; and

wherein the electrochromic window exhibits an E_v of less than approximately 20 while in a low transmission state during normal daylight conditions.

16. The aircraft window system according to claim 15, wherein the electrochromic window exhibits an E_v of less than approximately 10 while in a low transmission state during normal daylight conditions.

17. The aircraft window system according to claim 15, wherein the electrochromic window exhibits an E_v of less than approximately 5 while in a low transmission state during normal daylight conditions.

18. The aircraft window system according to claim 15, wherein the electrochromic medium further comprises at least one of an anodic and cathodic color-stabilizing redox buffer.

19. The aircraft window system according to claim 15, wherein the electrochromic medium further comprises anodic and cathodic color-stabilizing redox buffers.

20. The aircraft window system according to claim 15, wherein the concentration of the at least one cathodic electroactive material is greater than the combined concentration of the first and second anodic electroactive materials.

21. The aircraft window system according to claim 15, wherein the at least one cathodic electroactive material comprises a viologen.

22. The aircraft window system according to claim 21, wherein the viologen comprises a 1,1′

-dialkyl-4,4′

-dipyridinium compound and wherein at least one alkyl group attached to the dipyridinium compound comprises at least 4 carbon atoms and includes less than 2 β

hydrogen atoms.

23. The aircraft window system according to claim 15, wherein the first anodic electroactive material comprises a phenazine.

24. The aircraft window system according to claim 23, wherein the phenazine comprises a 5,10-dialkyl-5,10-dihydrophenazine compound, wherein at least one alkyl group attached to the phenazine compound comprises at least 4 carbon atoms and is void of any β

hydrogen atoms.

25. The aircraft window system according to claim 24, wherein the phenazine comprises a neopentyl group.

26. The aircraft window system according to claim 15, wherein the electrochromic medium further comprises at least one of a cross-linked polymer matrix, a free-standing gel, and a substantially non-weeping gel.

27. The aircraft window system according to claim 15, wherein a substrate is less than approximately 1.0 mm thick.

28. A variable transmission electrochromic window, comprising:

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

a second substantially transparent substrate having an electrically conductive material associated therewith;

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

at least one solvent;

a first anodic electroactive material;

a second anodic electroactive material;

at least one cathodic electroactive material; and

wherein at least one of the anodic and cathodic electroactive materials is electrochromic; and

means associated with the electrochromic window for exhibiting an E_v of less than approximately 20 while in a low transmission state during normal daylight conditions.