METHOD FOR MANUFACTURING TUNGSTEN OXIDE FINE PARTICLE EXHIBITING ELECROCHROMIC CHARACTERISTIC, COATING LIQUID CONTAINING THE FINE PARTICLE, AND ELECTROCHROMIC ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing tungsten oxide fine particles exhibiting electrochromic characteristics with a simple process and at a low cost, and to provide an electrochromic element having uniform characteristics even when coating a large area by a coating method using a coating liquid in which the fine particles are dispersed. SOLUTION: Fine particles of tungsten trioxide are obtained by dissolving tungsten hexachloride in alcohol, separating a precipitate, which is generated by evaporating the solvent or by adding water, from the solvent and subsequently heating at 100-500 deg.C. An electrochromic layer is formed by dispersing the fine particles in a liquid so as to form the liquid to be applied with =200 nm average dispersed particle size of the fine particles, applying the liquid to a substrate with an attached transparent conductive film and hardening it. The flexible electrochromic element with a film shape is stuck to an existing window of a house, a building, an auto car or the like so as to form a dimmer window.