Electrochromic media and devices with multiple color states

• US 10,781,364 B2
• Filed: 10/20/2017
• Issued: 09/22/2020
• Est. Priority Date: 10/20/2016
• Status: Active Grant

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Franz, Sue F., Baumann, Kelvin L.
• Primary Examiner(s): Ahvazi, Bijan
• Application Number:
  US15/789,802
• Publication Number:
  US 20180112127A1
• Time in Patent Office: 1,068 Days
• CPC Class Codes: B60J 3/007 Sunglare reduction by coatings, interposed foils in laminar windows, or permanent screens layered glass products B32B17/00; process of coating windows C03C17/00
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: C09K 2211/1018 Heterocyclic compounds
• CPC Class Codes: C09K 2211/1022 bridged by heteroatoms, e.g. N, P, Si or B
• CPC Class Codes: C09K 9/02 Organic tenebrescent materials
• CPC Class Codes: E06B 2009/2464 featuring transparency control by applying voltage, e.g. LCD, electrochromic panels
• CPC Class Codes: E06B 9/24 Screens or other constructions affording protection against light, especially against sunshine; Similar screens for privacy or appearance; Slat blindsoperating, guiding or securing devices or arrangements for roll-type closures E06B9/56; free-hanging flexible screens A47H23/00
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions
• 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

Abstract

An electrochromic medium includes a solvent, a first pair of a first anodic material and a first cathodic material, and at least one of a second anodic material and a second cathodic material. At least one of the first anodic material and the first cathodic material is an electrochromic absorbing in the visible range, and at least one of the second anodic material and the second cathodic material is electrochromic absorbing in the visible range.

Claims

1. An electrochromic medium comprising:

a solvent;

a first pair of a first anodic material and a first cathodic material; and

a second anodic material, a second cathodic material, or both the second anodic material and the second cathodic material;

wherein

a difference between the absolute value of a first redox potential of the first anodic material and the absolute value of a first redox potential of the second anodic material is greater than 0;

a difference between the absolute value of a first redox potential of the first cathodic material and the absolute value of a first redox potential of the second cathodic material is greater than 0;

at least one of the first anodic material and the first cathodic material is electrochromic and exhibits a first absorption maxima in the visible range; and

at least one of the second anodic material and the second cathodic material is electrochromic and exhibits a second absorption maxima in the visible range different from the first absorption maxima, with the proviso that should only one of the second anodic material or the second cathodic material be present, that one exhibits the second absorption maxima;

configured to provide that the first absorption maxima but not the second absorption maxima is exhibited upon application of a potential to the electrochromic medium that is less than the absolute value of the first redox potential of the second anodic material and the second cathodic material that is electrochromic;

wherein at least one of the first cathodic material and the second cathodic material comprises a compound of Formula I, Ill, IV, X, or XI;

2. The electrochromic medium of claim 1, wherein the first pair and the at least one of the second anodic material and the second cathodic material are configured to provide a first color upon application of a potential to the electrochromic medium that is less than the absolute value of the first redox potential of the at least one of the second anodic material and the second cathodic material that is electrochromic, and a second color upon application of a potential to the electrochromic medium that is about or above the first redox potential of at least one of the second anodic material and the second cathodic material that is electrochromic.

3. The electrochromic medium of claim 1, wherein an absorption spectrum of the first pair is different than an absorption spectrum of at least one of the second anodic material and the second cathodic material.

4. The electrochromic medium of claim 1, comprising the second anodic material that exhibits a second absorption maxima in the visible range different from the first absorption maxima;

wherein

the first anodic material exhibits a first redox potential and a second redox potential, where the absolute value of the second redox potential of the first anodic material is greater than the absolute value of the first redox potential of the first anodic material;

the first anodic material is electrochromic and exhibits the first absorption maxima in the visible range; and

the absolute value of the second redox potential of the first anodic material is greater than the absolute value of the first redox potential of the second anodic material.

5. The electrochromic medium of claim 1, comprising the second cathodic material that exhibits a second absorption maxima in the visible range different from the first absorption maxima;

wherein

the first cathodic material exhibits a first redox potential and a second redox potential, where the absolute value of the second redox potential of the first cathodic material is greater than the absolute value of the first redox potential of the first cathodic material;

the first cathodic material is electrochromic and exhibits the first absorption maxima in the visible range; and

the absolute value of the second redox potential of the first cathodic material is greater than the absolute value of the first redox potential of the second cathodic material.

6. The electrochromic medium of claim 1, wherein

the difference between the absolute value of a first redox potential of the first anodic material and the absolute value of a first redox potential of the second anodic material is at least about 110 mV;

the difference between the absolute value of a first redox potential of the first cathodic material and the absolute value of a first redox potential of the second cathodic material is at least about 110 mV.

7. The electrochromic medium of claim 1, wherein the electrochromic medium comprises:

the first pair of the first anodic and the first cathodic material;

a second pair of the second anodic and the second cathodic material;

wherein

a difference between the absolute value of the redox potential of the first pair and the absolute value of the redox potential of the second pair is at least about 110 mV; and

at least one of the second anodic material and the second cathodic material is electrochromic and exhibits a second absorption maxima in the visible range different from the first absorption maxima.

8. The electrochromic medium of claim 7, wherein absorption spectrum of the first pair is different than absorption spectrum of the second pair.

9. The electrochromic medium of claim 1, wherein

a difference between the absolute value of a first redox potential of the first anodic material and the absolute value of a first redox potential of the first cathodic material is no more than about 2000 mV;

and

a difference between absolute value of the first redox potential of the second anodic material and the absolute value of the first redox potential of the second cathodic material is no more than about 2000 mV.

10. The electrochromic medium of claim 1, wherein at least one of the first cathodic material and the second cathodic material comprises the compound of Formula I or X.

11. The electrochromic medium of claim 1, wherein at least one of the first cathodic material and the second cathodic material comprises the compound of Formula III, IV, or XI, wherein R²³, R²⁴, R³³, R³⁴, R¹²³, and R¹²⁴ are each independently alkyl, siloxy alkyl, hydroxyalkyl, alkenyl, or aralkyl.

12. The electrochromic medium of claim 1, wherein at least one of the first anodic material and the second anodic material comprises the compound of Formula II.

13. The electrochromic medium of claim 1, wherein at least one of the first anodic material and the second anodic material comprises the compound of Formula V or VI.

14. The electrochromic medium of claim 1, wherein at least one of the first anodic material and the second anodic material.

15. The electrochromic medium of claim 1, wherein the solvent comprises a carbonate, a halogenated solvent, an ether, an ester, a ketones, an tertiary amide, a nitrile, a sulfoxide, a sulfone, or a mixture of any two or more thereof.

16. The electrochromic medium of claim 1, wherein electrochromic medium is a solid state, solution phase, a gel, an electrochromic thermoplastic, or a cross-linked material.

17. The electrochromic medium of claim 1, wherein the electrochromic medium is substantially transparent absent application of a potential.

18. An electrochromic device comprising:

the electrochromic medium of claim 1; and

a chamber defined by a first conductive surface of first substrate, a second conductive surface of a second substrate, and a sealing member joining the first substrate to the second substrate, wherein the electrochromic medium is disposed within the chamber.

19. The electrochromic device of claim 18 which is an electrochromic window, an electrochromic sun visor, an electrochromic sun roof, or an electrochromic mirror.