Patent ID: 7064212

Claim:
An electrochromic salt having the chemical formula [A][B] 2 wherein B is selected from the group consisting of bis(perfluoroethylsulfonyl)imide and tris(trifluoromethylsulfonyl)methide and wherein A is a dication having the structural formula wherein R 1 and R 1 ′ are independently selected fmm alkyl having 1–20 carbons, aryl, aikyl-substituted aryl having 7–20 carbons, methoxy-substituted aryl having 7–20 carbons, nitro-substituted aryl having 6–20 carbons, cyano-substituted aryl having 7–20 carbons, trifluoromethyl-substituted aryl having 7–20 carbons; wherein R 2 , R 2 ′, R 3 and R 3′ are independently selected from hydrogen, alkyl having 1–20 carbons, aryl, alkyl-substituted aryl having 7–20 carbons, methoxy-substituted aryl having 7–20 carbons, nitro-substituted aryl having 6–20 carbons, cyano-substituted aryl having 7–20 carbons, trifluoromethyl-substituted aryl having 7–20 carbons; or wherein A is a dication having the structural formula wherein R 4 and R 4 ′ are independently selected from alkyl having 1–20 carbons; wherein R 5 , R 5 , R 6 , R 6′ , R 7 , R 7′ , R 8 , and R 8′ , are independently selected from hydrogen, alkyl having 1–20 carbons, aryl, alkyl-substituted aryl having 7–20 carbons, methoxy-substituted aryl having 7–20 carbons, nitro-substituted aryl having 6–20 carbons, cyano-substituted aryl having 7–20 carbons, trifluoromethyl-substituted aryl having 7–20 carbons.