| abstract |
The present invention provides solution-phase electrochromic devices, including such devices that are single-compartment and self-erasing, in which the media of variable transmittance are solutions comprising, as cathodic electrochromic compounds, certain 4,4'-bipyridinium salts, such as salts of 1,1'-dibenzyl-2,2',6,6'-tetraalkyl-4,4'-bipyridinium cations. Electrochromic devices of the invention are components of variable transmittance in display devices, windows and other types of light filters, and variable reflectance mirrors, such as those that can be used as dimmable rearview mirrors in motor vehicles. |