'Electric-paint displays' with carbon counter electrodes

'Electric-paint displays' are electrochromic displays with dyed nanostructu red metal-oxide electrodes, e.g. viologen-derivatized nanostructured titani um dioxide electrodes. Such displays are particularly promising for applica tions with low switch frequency, large segment areas, and high demands on c olours, background brightness, and large viewing-angles. The concept is sim ple and well suited for inexpensive industrial production methods. We prese nt blue-on-white electric-paint displays with porous carbon counter electro des. The initial results with laboratory prototypes are promising. The swit ch time is about 1/2 s and the reflectance in the bleached state is as high as 40-55% in the visible region. Furthermore, the display prototypes susta in more than 100 000 switching cycles without severe degradation. The resul ts from spectroelectrochemical measurements on the assembled displays are p resented. (C) 2001 Elsevier Science Ltd. All rights reserved.