Abstract: An electrochromic device comprises an electrochromic layer comprising a transition metal compound sandwiched in between a first auxiliary electrochromic layer and a second auxiliary electrochromic layer, each of the auxiliary electrochromic layers comprising at least one metal compound containing at least one metal different from the metal in the transition metal compound in the electrochromic layer, and the difference in electro-negativity between both metals being not more than 0.4.

Abstract: An electrochromic device for use in a display apparatus which is basically constructed with an electrochromic layer containing therein a metal oxide compound, an auxiliary electrochromic layer containing therein at least one kind of metal compound which contains at least one kind of metal element, wherein the difference in electro-negativity between the metal element in the metal compound and the metal element contained in the metal oxide constituting the electrochromic layer is 0.4 or less, both the electrochromic layer and the auxiliary electrochromic layer being laminated, and a pair of electrodes holding between them the laminated electrochromic layer and auxiliary electrochromic layer, at least one of the pair of electrodes being light transmissive.