Patent ID: 7342708

Claim:
A complementary electrochromic device, comprising: a first conductive layer; a second conductive layer, which may be the same as or different from the first conductive layer; a cathodically coloring polymer layer in electrical contact with the first conductive layer; an anodically coloring substance layer in electrical contact with the second conductive layer; a transparent electrolyte layer positioned between and in contact with both the cathodically coloring polymer layer and the anodic coloring substance layer; wherein: upon application of a negative voltage to the first conductive layer relative to the second conductive layer, the cathodically coloring polymer layer and the anodically coloring substance layer are both in a low transmissivity state and upon application of a positive voltage to the first conductive layer relative to the second conductive layer, the cathodically coloring polymer and the anodically coloring substance layer are both in a high transmissivity state; wherein: the cathodically coloring polymer has the chemical structure: wherein: R 1 is selected from the group consisting of [—CH 2 —] r —CH 2 CH(R 2 )— and —CH 2 C(R 3 )(R 4 )CH 2 —; r is 1, 2, 3, or 4; n is the number of repeat monomer units in the polymer; R 2 is selected from the group consisting of branched or straight-chain (1C-20C)alkyl, hydroxy(1C-20C)alkyl, methoxy(1C-20C)alkyl and phenyl; R 3 and R 4 are independently selected from the group consisting of branched or straight-chain (1C-10C)alkyl and phenyl; and, the anodically coloring substance comprises a chemical compound selected from the group consisting of an indium hexacyanometallate and a transition metal hexacyanometallate.