ELECTROCHROMIC DEVICES

• US 20110149366A1
• Filed: 12/18/2009
• Published: 06/23/2011
• Est. Priority Date: 12/18/2009
• Status: Abandoned Application

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Pollino, Joel M., Percec, Simona
• Application Number:
  US12/641,474
• Publication Number:
  US 20110149366A1
• Time in Patent Office: Days
• US Class Current: 359/265
• CPC Class Codes: G02F 1/153 Constructional details

Abstract

Disclosed are electrochromic devices incorporating electrochromic materials containing a film-forming polymer with a T_g less than 100° C.; a plasticizer; an electrochromophore; an electron mediator; and a salt. Such electrochromic devices can provide light-filtering, color-modulation, or reflectance-modulation in variable transmittance windows, variable-reflectance mirrors and other dynamic glazing applications.

Claims

1. A device comprising:

(a) a first substrate with a conductive surface;

(b) a second substrate with a conductive surface; and

(c) a composition comprising;

(i) 10-60 wt % of a polymer selected from the group of amorphous, film-forming polymers with T_g less than 100°

C.;

(ii) 45-70 wt % of a plasticizer, wherein the plasticizer is soluble in the polymer to at least 45 wt %;

(iii) 1-30 wt % of an electrochromophore, wherein the electrochromophore is soluble in the plasticizer to at least 10 wt %;

(iv) 0.1-10 wt % of an electron mediator selected from the group consisting of ferrocene, butyl ferrocene, ferrocene carboxylic acid, phenazine and its derivatives, carbazole and its derivatives, phenothiazine and its derivatives, and phenanthroline and its derivatives; and

(v) 0.1-10 wt % of a salt selected from the group consisting of lithium chloride, tetrabutylammonium bromide, lithium bis(trifluoromethanesulfonyl)imide, lithium triflate, and lithium hexafluorophosphate,

wherein the melting point of the plasticizer is not above about 0°

C., the boiling point of the plasticizer is above about 190°

C. at a pressure of 1 atmosphere, and the solubility in the plasticizer of the electrochromophore, the electron mediator and the salt are each at least 0.05 mg per mg of plasticizer,

wherein the composition is in contact with the conductive surfaces of the first and second substrates, wherein at least one substrate and associated conductive surface is transparent.

2. The device of claim 1, wherein the composition forms a 1-200 microns thick layer between the conductive surfaces of the first and second substrates.

3. The device of claim 1, wherein at least one of the first and second substrates is ITO-coated glass or ITO-coated PET.

4. The device of claim 1, wherein the amorphous film-forming polymer is selected from the group consisting of polyvinyl butyral, polyvinyl chloride, polycarbonate, polyvinyl alcohols, acrylate (co)polymers, ethylene-vinyl alcohol copolymers, ethylene-acrylate copolymers, ethylene-CO-acrylate terpolymers, and polyurethanes.

5. The device of claim 1, wherein the plasticizer is selected from the group consisting of linear carbonates;

cyclic carbonates;

C₇-C₁₀ linear primary alcohols;

linear and branched C₅-C₁₂ aliphatic diols, linear and branched C₅-C₁₂ aliphatic triols;

benzyl alcohol;

1-phenoxy-2-propanol;

linear and cyclic ureas;

linear or cyclic urethanes;

thioureas;

thiourethanes;

linear thio-oxocarbonates;

pyrrolidon-2-ones;

dihydrofuran-2-ones;

piperidin-2-ones;

pyran-2-ones;

substituted imidazolium salts;

3-methanesulfinylmethyl-heptane;

2-(2-butoxyethoxy)ethanol;

bis-cyclics of Structure II,

6. The device of claim 1, wherein the plasticizer is selected from the group consisting of propylene carbonate;

4-(hydroxymethyl)-1,3-dioxolan-2-one;

carbonic acid dibutyl ester;

1-(3-hydroxypropyl)2-pyrrolidone;

1-octyl-2-prrolidone;

5-dodecanolide;

1-hexyl-3-methylimidazolium chloride;

1-methyl-3-octylimidizolium chloride;

2,2-dimethyl-1,3-hexanediol;

2-methyl-1,3-pentanediol;

1-cyclohexyl-2-methyl-1,3-pentanediol;

2,4-diethyl-1,5-pentanediol;

1,3-nonanediol;

2-butyl-1,3-octanediol;

3-methylpentane-1,3,5-triol;

2-ethyl-1,3-hexanediol;

benzyl alcohol;

3-methyl-1,5-pentanediol;

1-phenoxy-2-propanol;

2-(2-butoxyethoxy)ethanol;

bis(2-ethylhexyl)phosphate;

tributyl phosphate; and

tris(2-ethylhexyl)phosphate.

7. The device of claim 1, wherein the electrochromophore is a copolymer of 4-4′

-dipyridyl and poly(ethylene glycol).

8. The device of claim 7, wherein poly(ethylene glycol) has a molecular weight of about 100 to about 2000 Daltons.

9. A method comprising applying a voltage of 0.1-10 V between the conductive surfaces of the first and second substrates of a device of claim 1.

10. An article comprising the electrochromic device of claim 1.

11. The article of claim 10 selected from the group consisting of windows and mirrors.