Light-stable electrochromic system for e.g. windows, protective glasses or car mirrors contains an electrochromic medium and a yellow filter with an absorption peak of specified wavelength

摘要

A light-protected electrochromic system with an electrochromic medium between two sheets of glass or plastic contains a yellow filter in which the wavelength at which the extinction on the long-wavelength side reaches half the maximum extinction at the longest wavelength is in the range between 370 and 500 nm, preferably 380-470 nm. A light-protected electrochromic system comprises: (a) Two sheets of glass or plastic, or plastic film, one of which (preferably both) is/are coated on one side with an electrically conductive coating, at least one of these sheets and its coating being transparent and the other possibly metallized, and with the conductive coating on at least one of the sheets possibly being divided into separate, individually-contacted surface segments; (b) a sealing ring between the sheets on the conductive coating side; and (c) an electrochromic medium filling the space between the two sheets. The system contains a yellow filter in which the wavelength at which the extinction on the long-wavelength side of the absorption curve reaches half the maximum extinction value at the longest wavelength is in the range 370-500 (preferably 380-470) nm. An Independent claim is also included for electrochromic substances of formula (LX). R<3> = -(CH2)3-Ph or -(CH2)4-Ph; Z<1> = a direct bond; E<5> = N-Ph, N-(CH2)3-Ph or N-(CH2)4-Ph; m = 3-5; X = redox-inert anion; and Ph = phenyl.