Electrochromic display device

Abstract

An electrochromic display device comprising a pair of electrodes which are disposed with a specified space therebetween, at least one of the electrodes being transparent, and a non-aqueous electrolytic solution filled in the space and comprised of a styryl-like compound and a supporting electrolyte dissolved in a solvent, the styryl-like compound being represented by the formula: ##STR1## in which Q represents a benzene ring with or without substituents and/or a condensed ring, R.sub.1 and R.sub.2 independently represent a lower alkyl group, a hydroxyalkyl group or an alkoxyalkyl group, R.sub.3 represents hydrogen, an alkyl group, an alkoxy group, a halogen, a nitrile group, an aromatic group or a phenoxy group, Y represents oxygen or sulfur, Z represents an alkylene group of 2 to 4 carbon atoms, with or without an alkyl substituent, required to complete a ring structure together with ##STR2## and A represents a residue resulting from a condensation reaction of the methyl group of methylene group in the 2-position of a precursor indoline derivative of the formula: ##STR3## where Q, R.sub.1, R.sub.2, R.sub.3, Y and Z have the same meanings as defined above with a member selected from the group consisting of aromatic aldehydes, heterocyclic aldehydes, aromatic nitroso compounds and heterocyclic nitroso compounds.