POLYMER HAVING ISOTHIANAPHTHENE STRUCTURE AND ELECTROCHROMIC DISPLAY

摘要

A polymer having an isothianaphthene structure represented by the formula (Ia) and/or (Ib): where R<1> and R<2> each represents a hydrogen atom or a hydrocarbon residue having 1 to 5 carbon atoms such as methyl, methoxy and thiomethyl or R<1> and R<2> together form, along with the benzene ring, a fused ring which is naphthdlene; X is sulfur, selenium or tellurium; Y represents an anion of an electrolyte; z represents a number from 0.01 to 1 showing a ratio of the anion per mol of a monomer; n represents a number of from 5 to 500 showing a degree of polymerization. The polymer is useful in an electrochromic display wherein a conductive membrane of the polymer formed on a conductive transparent base is used as a display base and an opposing electrode is arranged thereunder via a liquid electrolyte.