Patent ID: 6509999
Filing Date: 2003-01-21
Classification: C09K,G02F

Abstract:
An electrochromic device with improved switching behavior comprising:(a) a pair of glass plates, a pair of plastic plates, or a pair of plastic films, (b) an electrically conductive coating located on a side of at least one of the glass plates, the plastic plates, or the plastic films, wherein the pair of glass plates, plastic plates or plastic films are joined together via a sealing ring located on the side at which the electrically conductive coating is located and wherein the pair of glass plates, plastic plates, or plastic films and the sealing ring form a volume; (c) an electrochromic medium, contained in the volume, that comprises (i) a first reducible electrochromic compound OX2, and a second reducible electrochromic compound OX3 in an amount no greater than 30% of the concentration of OX2, having a reduction potential the value of which is not greater than the value of the reduction potential of the first reducible electrochromic compound, and (ii) a first oxidizable compound RED1 and a second oxidizable compound RED3 in an amount no greater than 30% of the concentration of RED1, having an oxidation potential the value of which is not greater than the value of the oxidation potential of the first oxidizable electrochromic compound; wherein at least one plate or at least one film and the conductive coating is transparent, and wherein the electrically conductive coating in at least one of the plastic plates, the glass plates, or the two films can be divided into separate, individually contacted area segments and the conductive coating can be connected at at least one point to an electrical conductor.