Recent trend in thin film formation for electrochromic display materials.

Abstract

Elctrochromic materials and thin film formation techniques are reviewed. Transition metal oxides, such as WO3, MoO3, NiOOH, and IrOx are chemically or electrochemically filmed on ITO glasses. These methods can be used for the large scale production of the desplay surface.In the case of organic materials, viologens are the most comonly used. During repeated coloration and bleaching, these materials are, however, easily converted into irreversible species. This is stabilized by clusrate formation with cyclodextrin.Anodic polymerization of aniline or pyrole is of alternate possibillity of the organic electrochromic materials. Since the ECD is one of the electrochemical cells, the two electrodes and electrolyte between them are the basic components. Therefore, the selection of the electrolyte is of great importance, as well as the selection of the elctrochromic materials.Finally the merit and demerit of the ECD are described.