EP0430686A2
Expired / Lapsed
EP
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Electrochemichromic viologens
Assignee: Magna Donnelly Corp
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Filing: 1990-11-29
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Granted: —
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Expires: 2010-11-29
Abstract
Abstract Electrochemichromic solutions, and devices containing such solutions contain viologens whose solubility can be enhanced by the use of hexafluorophosphate (PF₆⁻) or hexafluoroarsenate (AsF₆⁻), or a mixture thereof as a counterion.
Inventors
- 👤 Desaraju V. Varaprasad
- 👤 Niall R. Lynam
- 👤 Hamid R. Habibi
- 👤 Padma Desaraju
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 09:27
CPC Classifications
C; C09; C09K; C09K9/00; C09K9/02; G; G02; G02F; G02F1/00; G02F1/01; G02F1/15; G02F1/1503; G02F2001/1502; G02F1/1514; G02F2001/15145
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
44 words
An electrochemichromic solution comprising a solvent and a redox chemical pair which is capable of being coloured or colourless depending on any voltage applied to the solution, one of the redox pair comprising a viologen hexafluorophosphate or a viologen hexafluoroarsenate or a mixture thereof.
Claim 2
Dependent Claim
13 words
An electrochemichromic solution as claimed in claim 1 wherein the viologen is methylviologen.
Claim 3
Dependent Claim
24 words
An electrochemichromic solution as claimed in claim 1 or 2 wherein the viologen is in solution at a concentration of at least 0.05 M.
Claim 4
Dependent Claim
34 words
An electrochemichromic solution as claimed in any of claims 1 to 3 wherein the solvent comprises at least 25% by volume of propylene carbonate, 3-hydroxypropionitrile, 3,3′-oxydipropionitrile, 2-acetylbutyrolactone, 3-methylsulpholane or 2-methylglutaronitrile, or a mixture thereof.
Claim 5
Dependent Claim
19 words
An electrochemichromic solution as claimed in any of claims 1 to 4 wherein the solvent is substantially entirely 2-acetylbutyrolactone.
Claim 6
Dependent Claim
43 words
An electrochemichromic solution as claimed in any of claims 1 to 5 wherein a cathodic member of the redox chemical pair in solution is methylviologen hexafluorophosphate and hexafluoroarsenate or ethylviologen hexafluorophosphate and hexafluoroarsenate, or a mixture thereof and/or an anodic member is 5,10-dihydro-5,10-dimethylphenazine.
Claim 7
Dependent Claim
75 words
An electrochemichromic device comprising: at least two spaced apart plates, each plate having an inwardly facing conductive surface, and an electrochemichromic solution located in the device between said inwardly facing conductive surfaces, the solution comprising a solvent and a redox chemical pair which is capable of being coloured or colourless depending on any voltage applied to the solution, one of the redox pair being a viologen hexafluorophosphate or a viologen hexafluoroarsenate or a mixture thereof.
Claim 8
Dependent Claim
23 words
An electrochemichromic device as claimed in claim 7 wherein the solution is a solution as claimed in any of claims 2 to 6.
Claim 9
Independent Claim
31 words
A method of increasing the solubility of a viologen in an electrochemichromic solution the method comprising comprising providing hexafluorophosphate (PF₆⁻), or hexafluoroarsenate (AsF₆⁻) or a mixture thereof, as the viologen counterion.
Claim 10
Dependent Claim
20 words
A method as claimed in claim 9 wherein the solution is as claimed in any of claims 1 to 6.
Claim 11
Dependent Claim
27 words
A process for the preparation of an electrochemichromic solution as claimed in any of claims 1 to 6, the process comprising admixing the redox pair and solvent.
References Cited (Backward Citations)
No citation records indexed.
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