JP6452311B2 - Electrochromic element - Google Patents

Description

  The present invention relates to an electrochromic device.

  An electrochromic element is an element having a pair of electrodes, an electrochromic compound disposed between the pair of electrodes, and an electrolyte. Visible light transmittance is changed by oxidizing or reducing the electrochromic compound. An electrochromic compound is a compound having electrochromic properties, and is a compound whose light transmittance varies depending on the state of the compound. ND filters and window materials using electrochromic elements having this electrochromic compound are known.

  As the electrochromic element, a form having an electrochromic compound as a solid layer and a form having a liquid in which an electrochromic compound is dissolved are known. An element having a liquid in which an electrochromic compound is dissolved may be referred to as a solution type electrochromic element.

  And it is known that oxygen, water, etc. in a solution will inhibit the decoloring reaction of an electrochromic compound.

  Patent Document 1 describes an organic electrochromic element to which an antioxidant is added in order to remove oxygen in a solution.

JP 2011-081409 A

  The antioxidant described in Patent Document 1 has high solubility in a solution containing an electrochromic compound, and suppresses oxidation of the electrochromic compound by oxidizing itself. However, because the solubility of the antioxidant is high, the antioxidant is present throughout the solution containing the electrochromic compound, and the antioxidant itself is easily oxidized, thereby inhibiting the oxidation reaction of the electrochromic compound. .

  When using what has high solubility with respect to the solution containing an electrochromic compound, not only antioxidant but the electrochromic reaction of an electrochromic compound will be inhibited as mentioned above.

  The present invention provides a solution-type electrochromic device which is an electrochromic device in which an electrochromic reaction such as a decoloring reaction is hardly inhibited by water, oxygen, or the remover itself even if a remover that removes water or oxygen is used. The purpose is to provide.

Accordingly, the present invention provides a pair of substrates, a pair of electrodes disposed between the pair of substrates, a liquid in which an electrochromic compound and an electrolyte disposed between the pair of electrodes are dissolved, An electrochromic element having a wall disposed between the pair of substrates, the liquid further comprising a remover insoluble in the liquid,
The wall is a wall that holds the remover at a position away from the electrode, and an electrochromic element, a pair of electrodes, and an electrochromic layer disposed between the pair of electrodes, An electrochromic device having a remover contained in the electrochromic layer, wherein the remover is fixed by an adhesive.

  According to the present invention, by providing a remover that removes water or oxygen that is insoluble in the liquid of the electrochromic device, the electrochromic device is less likely to inhibit the decoloring reaction by water, oxygen, and the remover itself. can do.

(A) It is a cross-sectional schematic diagram of the cross section of a parallel direction with the electrode surface of the electrochromic element which concerns on this embodiment. (B) It is a cross-sectional schematic diagram of the orthogonal | vertical direction with respect to an electrode. It is a cross-sectional schematic diagram of the direction parallel to the electrode surface of the electrochromic element which has a wall concerning this embodiment. It is a cross-sectional schematic diagram of the direction parallel to the electrode surface of the electrochromic element which concerns on this embodiment, (a) thru | or (g) is a figure which shows the various aspects of a wall.

  The present invention is an electrochromic device having a liquid having an electrochromic compound and an insoluble remover. Below, the liquid which has an electrochromic compound may be called a liquid.

  FIG. 1A is a schematic cross-sectional view of an electrochromic device having a pair of electrodes facing each other and a liquid disposed between the pair of electrodes. A cross section is a cross section between a pair of electrodes, and is a cross section parallel to the electrodes. In the figure, one of the pair of electrodes is shown, but the other is not shown. FIG.1 (b) is a schematic diagram of a cross section perpendicular | vertical with respect to an electrode.

  This electrochromic element has an outer wall 1 for holding a liquid between a pair of opposing substrates, and the outer wall 1 has an opening 2 for injecting a liquid. The opening 2 is sealed by a sealing member (not shown). The electrochromic element has an electrode 3 and a substrate 4. The substrate is insulating. When a voltage is applied between the electrode 3 and the other electrode (not shown), the transmittance of the electrochromic element is changed.

  The liquid containing the electrochromic compound is present not only in the three regions shown in the figure, but also in the entire region of FIG. 1, that is, in the entire region surrounded by the outer wall 1. It is provided at a position away from the electrode 3 in the inward direction.

Insoluble in a liquid means that the concentration in the liquid does not become 1 × 10 ⁻¹⁰ M or more. M is a unit of concentration representing mol / L. The solubility is a solubility within a temperature range in which the electrochromic element is used. Specifically, it is 0 ° C. or higher and 100 ° C. or lower.

  The remover removes water or oxygen from the liquid by chemical reaction or physical adsorption.

  The electrode region is a portion where the light transmittance changes. An electrochromic element can be used for the optical filter.

  The remover 5 can be fixed with an adhesive or the like. When the adhesive to be used is fluid (for example, an epoxy or acrylic adhesive having fluidity), the remover 5 and the solid adhesive may be mixed and then placed on one substrate.

  In order to dispose the remover outside the electrode region, a wall 6 may be provided between the pair of electrodes of the electrochromic element. The wall is provided to hold the remover in a region different from the region of the electrode. FIG. 2 shows a form in which the wall 6 is held in a different area from the electrode 3.

  Even when the wall is provided, the liquid contacts the removing agent 5. The wall may be a mesh wall. Since the wall only needs to hold the removing agent at a predetermined position, the height may be equal to or less than the distance between the pair of electrodes. Even in this case, the liquid and the removing agent can contact each other.

  A plurality of walls may be provided. FIGS. 3A to 3G are diagrams showing another embodiment of the electrochromic device having a wall.

The material constituting the wall is not particularly limited, SiO _2, adhesive and the like. The adhesive may be either epoxy or acrylic.

  Examples of the removing agent include magnesium sulfate, sodium sulfate, calcium chloride, silica gel, clay, cerium oxide, zeolite, iron, activated carbon, porous silica and the like, and these can be used in combination.

  Among the removal agents, magnesium sulfate, sodium sulfate, calcium chloride, silica gel, clay, cerium oxide, and zeolite are removal agents that remove water in the liquid, and iron and activated carbon are removal agents that remove oxygen, and are porous. Silica is a remover for removing impurities.

  Oxygen and water include those that were present in the liquid from the beginning and those that entered the element from the air. Impurities include components that are not completely removed in the process of synthesizing an organic low-molecular electrochromic compound, specifically, other organic low-molecules, metal derived from a catalyst, and other components that are eluted from the sealant.

  When oxygen, water, and impurities are present in the liquid, these substances can be oxidized, reduced, or electrolyzed to inhibit the oxidation or reduction reaction of the electrochromic compound, that is, the coloring or decoloring reaction. There is sex.

  Examples of electrochromic compounds include viologen compounds, phenazine compounds, thiophene compounds, phthalate esters, and the like. These are classified into an anode material colored by oxidation and a cathode material colored by reduction, but only one or both may be used. In addition, a plurality of materials can be selected from each of the anode material and the cathode material.

  Examples of the liquid for dissolving the electrochromic compound include propylene carbonate, acetonitrile, γ-butyl lactone, dimethyl sulfoxide, dimethyl carbonate and the like.

  Examples of the electrolyte include lithium perchlorate, tetrabutylammonium perchlorate, and tetraethylammonium tetrafluoroborate. Moreover, even if there is no electrochromic property, you may add a bipolar organic low molecule (for example, ferrocene).

The concentration of the electrochromic compound and the electrolyte can be arbitrarily selected within the range of 1 × 10 ⁻⁸ M to 10M. M represents mol / L.

  The electrochromic device according to this embodiment can be used for an optical filter. The optical filter has an electrochromic element and an active element connected to the electrochromic element. Examples of the active element include a transistor and an MIM element. The transistor may include an oxide semiconductor in its active region. Examples of the oxide semiconductor include InGaZnO.

  The lens unit according to this embodiment includes an optical system having a plurality of lenses and an electrochromic element. The electrochromic element may be disposed between the plurality of lenses or may be disposed outside the lens.

  The electrochromic device according to the present embodiment can also be used for window materials such as airplanes and cars.

  The production of the electrochromic device according to the present invention will be described below. Two substrates having an electrode region 3 and an insulating region 4 on the outside thereof are opposed to each other at a constant interval, and an organic electrochromic solution is disposed between the two substrates. The peripheral portions of the opposing insulating regions are connected with an adhesive to form the outer wall 1. The outer wall has an inlet for injecting the solution. The insulating region 4 is necessary in order to easily adjust the size of the electrode 3.

A glass having one side coated with a transparent conductive film (thickness 100-2000 nm) such as FTO (fluorine-doped tin oxide) or ITO (indium-doped tin oxide) on a substrate having an electrode 3 and an insulating region 4 outside thereof. A substrate is processed and used. Specifically, a part of the transparent conductive film is removed by etching, a SiO ₂ film (thickness: 100 to 1000 nm) is formed by sputtering on the surface having the transparent conductive film, and the electrode 3 and the outside thereof are formed. The insulating region 4 can be formed.

  In order to connect the peripheral portions of the insulating regions 4 of the two substrates with an adhesive, an adhesive is applied on the insulating regions of one substrate so as to surround the electrodes, and then another sheet is formed. The substrate is bonded to the substrate, weighted, heated, and irradiated with ultraviolet rays to cure the adhesive.

  Epoxy and acrylic (both in liquid form) can be used as the adhesive. The former is Bond Quick Series (Konishi), the tract bond (Mitsui Chemicals), Toll Seal (Varian Agilent), and the latter is Bond Quick Series. (Konishi), TB3035B (Three Bond), Aron Alpha (Toagosei).

  Examples of a method for applying these adhesives in a specific shape include a dispenser and screen printing.

  For forming the outer wall, a sheet adhesive may be used in addition to the liquid adhesive. For example, if high Milan (Mitsui Dupont Fluorochemical) is cut into a specific shape, sandwiched between the insulating regions 4 of the two substrates, heated and heated, the peripheral portions of the insulating regions 4 of the two substrates are Can be connected.

  In order to make the two substrates face each other at a constant interval (10-100 μm), spacer beads having the same diameter as the substrate interval are mixed in the liquid adhesive and then applied. Micropearl (Sekisui Chemical), Unipearl (Unitika), etc. can be used for the spacer beads. Alternatively, the adhesive may be cured after a film spacer is disposed inside or outside the liquid adhesive / sheet adhesive so as not to overlap the electrode 3. The film spacer may be any as long as it does not change in the adhesive curing process, and Kapton (Toray DuPont), Melinex (Teijin DuPont) and the like can be used. When the adhesive is cured, the film spacer may be left between the two substrates, or may be removed if it is removable without being in contact with the adhesive.

  After the peripheral portions of the insulating regions 4 of the two substrates are connected to each other with an adhesive, an organic electrochromic solution is injected from the inlet 2 on the outer wall. A liquid crystal injector is used for injection, but when there are two injection ports, an organic electrochromic solution can be dropped onto the edge of the substrate under an inert atmosphere and normal pressure, and can be injected using a capillary phenomenon.

  After the injection, the injection port 2 is sealed in order to prevent the organic electrochromic solution from flowing out. As the adhesive used for sealing, the adhesive used for connecting the peripheral portions can be used. Alternatively, the injection port can be satire with another sealing member. Examples of other sealing members include wedge-shaped sealing members.

The wall for holding the removing agent of the electrochromic device of the present invention in a predetermined region is formed as follows. First, before connecting the peripheral portions of the insulating regions 4 of the two substrates with an adhesive, SiO ₂ is sputtered with the same thickness as the substrate interval, and the adhesive is applied with a thickness greater than the substrate interval. The wall 7 (precursor thereof) is produced by a method such as.

  Thereafter, an insoluble removing agent 5 for water, oxygen, or impurities is disposed. If the insoluble remover 5 is flexible, the thickness of the insoluble remover 5 may be greater than or equal to the substrate interval, equal to or less than the substrate interval, and if not flexible, equal to the substrate interval or less than the substrate interval. And When the precursor of the wall 7 is produced by applying an adhesive, the precursor is cured even before the peripheral portions of the insulating regions 4 of the two substrates are connected with the adhesive. There may be. A wall is formed in the above process, and the insoluble removing agent 5 is disposed inside the wall.

  The organic electrochromic solution injected from the inlet 2 on the outer wall moves in and out of the region separated by the wall through the opening 8 in the wall. Since the water, oxygen, or impurity remover 5 is disposed in this region, water, oxygen, or impurities in the entire organic electrochromic solution can be removed.

  A transmissive organic electrochromic device having an outer wall 1, an outer wall inlet 2, an electrode 3, and an insulating region 4 holds an insoluble removal agent 5 of water, oxygen, or impurities in a space sandwiched between the insulating regions 4. To do. Before the peripheral portions of the insulating regions 4 of the two substrates are connected to each other with an adhesive, the insoluble removing agent 5 is disposed or fixed on the insulating region 4 of one substrate, and after the peripheral portions are connected to each other. , Retained. As a result of the holding, the insoluble removing agent 5 does not enter the electrode 3.

DESCRIPTION OF SYMBOLS 1 Outer wall 2 Opening 3 Electrode 4 Insulating area 5 Remover 6 Wall 7 Wall 8 Opening of wall

Claims (11)

A pair of substrates, a pair of electrodes disposed between the pair of substrates, a liquid in which an electrochromic compound and an electrolyte are disposed between the pair of electrodes, and the pair of substrates An electrochromic device having a wall disposed therebetween,
The liquid further comprises a remover that is insoluble in the liquid,
The electrochromic device, wherein the wall is a wall that holds the removing agent at a position away from the electrode.   The electrochromic device according to claim 1, wherein the remover is a remover that removes water or oxygen from the liquid.   The electrochromic device according to claim 1, wherein the remover is disposed away from the electrode in an in-plane direction of the substrate.   The electrochromic device according to claim 1, wherein the removing agent is surrounded by the wall.   The electrochromic device according to claim 1, wherein the wall has a mesh shape.   The electrochromic device according to claim 1, wherein the removing agent is fixed by an adhesive. The electrochromic device according to any one of claims 1 to 6, characterized in that said removing agent is in contact with the liquid. Said removing agent, magnesium sulfate, sodium sulfate, calcium chloride, silica gel, clay, cerium oxide, zeolite, iron, activated carbon, any of claims 1 to 7, characterized in that at least either of the porous silica one The electrochromic device according to item. Optical filter having a electrochromic device according to any one of claims 1 to 8, and an active element connected to the electrochromic device. An optical system, a lens unit and having a electrochromic device according to any one of claims 1 to 9. Window material, characterized in that it comprises an electrochromic device according to any one of claims 1 to 9.

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