ELECTROCHROMIC DISPLAY DEVICE

PURPOSE:To obtain a display device having a display property with high contrast by forming the base of an electrochromic layer with a polymer in which isoindole or its conductor is set as a cycle unit. CONSTITUTION:A transparent electrode 12 is provided on one plane of a transparent glass substrate 11, and a hollow protection vessel 15 is arranged, and a counter electrode 14 is provided in the inner part of the protection vessel 15. On an electrode 12 on the other side, the electrochromic (EC) layers 10 are laminated so as to be positioned in the protection vessel 15, and an electrolyte layer 13 is interposed between the EC layer 10 and the electrode 14. Lead wires 16 are attached on the electrodes 12 and 14. A conductive polymer having isoindole structure represented in equation is used in the EC layer 10. Synthesis can be performed easily in the polymer, and high transparency is shown in an oxidation state. Where, R -R show the alkyl groups of an H, a halogen atom, and C number 1-5. As the electrolyte layer 13, tetraphenyl phosphonium chloride, etc., is used, and tetrahydrofuran, etc., is used as a solvent, and the raw material of the electrode 14 is not required to be specified.