Light valve and method of manufacturing the same, and light control glass assembly

Abstract

The present application relates to the field of electronic light control material, and provides a light valve, a manufacturing method thereof and a dimming glass assembly. In the light valve, a mixture of blue particles and yellow particles is distributed in liquid droplets of a light control layer suspending medium, the blue particles are selected from polyiodide compound particles, and the yellow particles are selected from PbCrO4 particles; the dark state of the light valve is non-blue, and the bright state is transparent. The light valve based on the mixed light control particles of the polyiodide compound particles and the PbCrO4 particles is simple to prepare, can conveniently and effectively modulate the non-blue dark state primary color and the transparent bright state, is beneficial to meet the demand of people for various colors, and has important significance.

Description

Technical Field

[0001] This invention relates to the field of electronic light control materials technology, and in particular to a non-blue-toned light valve, light control particles, a method for manufacturing the light valve, and a dimming glass assembly. Background Technology

[0002] A light valve is an electronic light-controlling device. It primarily consists of a light-controlling layer sandwiched between two transparent conductive films. When an electric field is applied, the arrangement or state of the electronically controlled light-controlling material in the light-controlling layer changes, thereby altering the device's light transmission characteristics, such as switching from low to high transmittance or vice versa. Through the action of the electric field, the light valve can achieve rapid switching between on and off states. Based on different light-controlling mechanisms, light valves can be classified as suspended particle light valves, polymer-dispersed liquid crystal light valves, and electrochemical reaction light valves. Depending on the substrate, light valves can use plastic sheets such as PET as the substrate, generally referred to as dimming films; or they can use glass as the substrate, generally referred to as dimming glass. Components formed by laminating dimming films are generally called dimming glass components. Light valves offer advantages such as active control of light transmittance and energy saving. This device can be used as smart windows, rearview mirrors, sunglasses, and displays in spacecraft, high-speed railways, automobiles, and buildings.

[0003] Over eighty years ago, light valves incorporating nanoparticles (i.e., suspended particle light valves) were developed. Although suspended particle dimming films have been successfully developed for many years, their dark state is blue. In practical applications, people don't particularly like this cool tone, preferring neutral shades like gray or other non-blue tones. Therefore, the previous technology of using blue in the dark state of suspended particle light valves, with its monotonous cool color, cannot meet people's demand for a rich variety of colors. Thus, a technology to better modulate the primary color of the light valve's dark state is needed. Summary of the Invention

[0004] In view of this, the present invention provides a non-blue-based light valve, its manufacturing method, and a dimming glass assembly. The light valve provided by the present invention can conveniently and effectively modulate a non-blue dark-state primary color to meet people's needs for a variety of colors.

[0005] This invention provides a light valve, comprising: a first transparent substrate, a first transparent electrode, a light-controlling layer, a second transparent electrode, and a second transparent substrate sequentially laminated together, wherein the first transparent electrode and the second transparent electrode are disposed opposite to each other; the light-controlling layer comprises a polymer matrix, wherein suspended medium droplets are dispersed in the polymer matrix, and solid light-controlling particles are distributed within the suspended medium droplets;

[0006] The solid light-controlling particles are a mixture of blue and yellow particles, wherein the blue particles are selected from polyiodine compound particles and the yellow particles are selected from PbCrO4 particles; the light valve has a non-blue tone in the dark state and is transparent in the bright state.

[0007] This invention provides a non-blue-based light valve. The dark state of this light valve is non-blue-based, and the bright state is colorless. It can conveniently and effectively modulate the non-blue dark-based primary color, which is beneficial for practical applications.

[0008] See Figure 1 , Figure 1 The diagram shows the structure of a dimming film provided in some embodiments of the present invention; wherein, 1 is two transparent electrodes arranged opposite to each other, 2 is a light control layer, 3 is two transparent substrates, 21 is a polymer matrix, 22 is a suspended medium droplet containing solid light control particles, and 23 is a solid light control particle, namely a mixture of blue and yellow particles of the present invention.

[0009] The light valve device provided in this embodiment of the invention includes two transparent electrodes 1 arranged opposite each other, which can be referred to as the first transparent electrode and the second transparent electrode for easy distinction. The transparent electrode is a component with conductivity and high visible light transmittance. Currently, the widely used transparent conductive material is indium tin oxide (ITO), and the visible light transmittance of ITO thin films is greater than 90%. Transparent thin-film conductive coatings can be used as transparent electrodes. These are transparent conductive films prepared using semiconductor compounds such as tin oxide, indium oxide, zinc oxide, etc., or by doping these compounds with small amounts of fluorine, antimony, etc. To ensure the excellent performance of the transparent electrode, the electrode thickness, impedance and conductivity, and transmittance are comprehensively controlled. Generally, the sheet resistance of a transparent electrode is less than 500 Ω / □, the visible light transmittance is greater than 80%, and the haze is less than 5.

[0010] In embodiments of the present invention, the first transparent electrode and the second transparent electrode are each independently selected from ITO conductive layer, FZO conductive layer (fluorine-doped zinc oxide conductive layer), IZO conductive layer, GZO conductive layer (conductive gallium-doped ZnO transparent conductive film), AZO conductive layer (Al-doped ZnO), PEDOT conductive layer (polyethylene dioxythiophene conductive layer), nano Ag wire conductive layer, conductive graphene and nano Cu wire conductive layer, for example, all of which are ITO conductive layers.

[0011] In this embodiment of the invention, a light-controlling layer 2 is disposed between two transparent electrodes 1 in the light valve. This layer includes a polymer matrix 21, in which multiple suspended medium droplets 22 containing solid light-controlling particles are dispersed. Furthermore, the solid light-controlling particles 23 in this embodiment are a mixture of blue and yellow particles. This invention uses a mixture of polyiodine compound particles and lead chromate (PbCrO4) particles as solid light-controlling particles, which allows the light valve to exhibit a non-blue hue in the dark state and to control the transparent bright state.

[0012] The solid light-controlling particles described in this invention can be commercially available products or prepared in-house. For example, yellow solid light-controlling particles PbCrO4 can be prepared from raw materials such as sodium chromate and lead nitrate through a hydrothermal reaction.

[0013] The specific preparation process of PbCrO4 solid light-controlling particles in a preferred embodiment of the present invention includes: sequentially adding an ionic surfactant, polyethylene glycol, Na2CrO4·4H2O, and water, stirring to dissolve, and denoting this as solution A. Pb(NO3)2 is dissolved in water under stirring, denoted as solution B. Under rapid stirring, solution B is slowly added to solution A, and the resulting mixed solution is then added to a hydrothermal reactor. The reaction is carried out at 80–200°C with stirring for 5–25 hours, followed by natural cooling. The resulting reaction solution is centrifuged, the supernatant is discarded, and unreacted raw materials are removed. The bottom of the flask contains a yellow product, which is washed to obtain yellow solid light-controlling particles 23. The ionic surfactant is preferably one or more of sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and hexadecyltrimethylammonium bromide (CTAB); in addition, the average molecular weight of polyethylene glycol (PEG, such as an average molecular weight of 400–60000) and the amount of polyethylene glycol added can be adjusted.

[0014] The specific process for preparing blue solid light-controlling particles in some embodiments of the present invention is as follows: 30g of an isoamyl acetate solution containing 20-22wt% nitrocellulose, 6g of I2, 70g of isoamyl acetate, and anhydrous CaI2 are added to a three-necked round-bottom glass flask, and heated to 40-50°C, preferably 42-45°C. After the I2 dissolves, anhydrous methanol, water, and 2,5-pyrazine dicarboxylic acid dihydrate are added to the above three-necked round-bottom glass flask, and the mixture is heated and stirred at 40-50°C, then allowed to cool naturally. The resulting reaction solution is centrifuged to remove large particles, and the supernatant is then centrifuged and discarded to obtain polyiodide blue solid light-controlling particles 23.

[0015] In embodiments of the present invention, the particle length of the solid light-controlling particles can be 50–800 nm, and the aspect ratio between the particle length and width is preferably 2–30, more preferably 3–25. In some specific examples, the yellow solid light-controlling particles have a particle length of 500 nm, a particle width of 50 nm, and an aspect ratio of 10; or, the yellow solid light-controlling particles have a particle length of 410 nm, a particle width of 50 nm, and an aspect ratio of 8.2; or the yellow solid light-controlling particles have a particle length of 350 nm, a particle width of 60 nm, and an aspect ratio of 5.8. As another example, the blue solid light-controlling particles have a particle length of 280 nm, a particle width of 70 nm, and an aspect ratio of 4.

[0016] In embodiments of the present invention, the preferred mass ratio of the yellow particles to the blue particles is (0.5-2):1; by adjusting the mass ratio of the two types of particles, different non-blue dark-state base colors can be formed.

[0017] This invention does not impose any special limitations on the polymer matrix and suspending medium in the light-controlling layer 2. Generally, the polymer matrix precursor and the suspending medium have a compatibility relationship, mainly reflected in their immiscibility, refractive indices being as close as possible, and densities being as close as possible. In the embodiments of this invention, the polymer matrix is ​​preferably formed by cross-linking and curing an organosilicon oil polymer matrix precursor with unsaturated bonds; the material forming the suspending medium droplets can be selected from at least one of fluorocarbon organic compounds, phthalates, triterpenes, dodecylbenzene, polybutene oil, polyacrylate, polymethyl methacrylate, epoxidized soybean oil, and epoxidized linseed oil.

[0018] In this embodiment of the invention, the initiator that initiates the crosslinking and curing of the polymer matrix precursor, the mixture of the suspension medium containing solid light-controlling particles 23 and the polymer matrix precursor are mixed evenly, and the resulting mixture is called the light-controlling layer matrix emulsion; it is coated on a transparent electrode to form a wet film, and then cured to obtain the desired product.

[0019] Furthermore, the transparent electrode 1 described in this embodiment of the invention is formed on two transparent substrates 3, corresponding to a first transparent substrate and a second transparent substrate. In some embodiments of the invention, the first transparent substrate and the second transparent substrate are glass plates, or in other embodiments, the first transparent substrate and the second transparent substrate are transparent plastic sheets.

[0020] To ensure a strong bond and ease of processing, in embodiments of the present invention, an adhesive layer is applied to the first and / or second transparent electrodes. Generally, the adhesive layer should have good adhesion to the polymer matrix to prevent delamination between the light-controlling layer and the transparent electrode, which could lead to loss of function of the dimming film. Furthermore, the adhesive layer material should not react with the light-controlling particles, thus preventing loss of function of the dimming film. Preferably, the adhesive layer material includes at least one of epoxy resin, polyurethane, polyimide resin, polystyrene resin, acrylic resin, modified acrylic resin, and silicone resin.

[0021] Accordingly, the present invention provides a method for manufacturing a light valve as described above, comprising:

[0022] Solid light-controlling particles are mixed with a suspension medium to form a mixture of suspension medium containing solid light-controlling particles; a polymer matrix precursor, an initiator for crosslinking and curing the polymer matrix precursor, and the mixture of suspension medium containing solid light-controlling particles are mixed to obtain a light-controlling layer matrix emulsion.

[0023] The above-mentioned light-controlling layer matrix emulsion is coated on the first transparent electrode of the first transparent substrate to form a light-controlling layer wet film;

[0024] The second transparent electrode on the second transparent substrate is covered on the light control layer wet film, and the light control layer wet film is crosslinked and cured to obtain the light valve.

[0025] The embodiments of this invention provide solid light-controlling particles, suspension media, and polymer matrix precursors, etc.; the specific preparation process of the yellow and blue solid light-controlling particles can be as described above. Preferably, this invention uses an organosilicon oil polymer matrix precursor with unsaturated bonds, which is cross-linked and cured to obtain the polymer matrix.

[0026] In this embodiment of the invention, a suspension medium such as DOIP (di(2-ethylhexyl) isophthalate) or TOTM (tris(2-ethylhexyl) trimellitate) is added to a round-bottom glass flask, and the isoamyl acetate dispersion of the yellow solid light-controlling particles prepared above is added in batches. The isoamyl acetate is removed by rotary evaporator, and finally, preferably, the mixture is further processed at 80°C using a rotary evaporator for 3 hours. After weighing, the mass of the solid light-controlling particles is calculated, and then an appropriate amount of DOIP is added and mixed evenly, preferably with a solid light-controlling particle / DOIP weight ratio of 1 / 12, to obtain a suspension containing yellow solid light-controlling particles. Similarly, this embodiment of the invention can obtain a suspension containing blue solid light-controlling particles.

[0027] In this embodiment of the invention, a mixture of a photoinitiator, a liquid suspension medium containing yellow solid light-controlling particles 23, a mixture of a liquid suspension medium containing blue solid light-controlling particles 23, and a prepared organosilicon oil polymer matrix precursor with unsaturated bonds are mixed evenly in a certain mass ratio to obtain a light-controlling layer matrix emulsion.

[0028] The initiator for initiating the crosslinking and curing of the polymer matrix precursor is preferably a photoinitiator, specifically photoinitiator 819 in this embodiment of the invention. The type of photoinitiator can be selected according to actual needs, and there are no special limitations. The initiator for initiating the crosslinking and curing of the polymer matrix precursor is preferably at least one of the following: 184 (CAS No. 947-19-3), ITX (CAS No. 5495-84-1 or 83846-86-0), 819 (CAS No. 162881-26-7), 1173 (CAS No. 7473-98-5), BDK (CAS No. 24650-42-8), BP (CAS No. 119-61-9), TPO (CAS No. 75980-60-8), 369 (CAS No. 119313-12-1), and 907 (CAS No. 71868-10-5). The amount (mass percentage) of the photoinitiator is preferably 0.05% to 1% of the polymer matrix precursor, more preferably 0.1% to 0.6%, and even more preferably 0.2% to 0.5%.

[0029] In this embodiment of the invention, the light-controlling layer matrix emulsion is coated onto a transparent conductive film substrate using a doctor blade-type automatic coating machine, with a preferred thickness of 60-100 micrometers. Another transparent conductive film substrate is then coated onto the wet film of the light-controlling layer matrix emulsion to obtain a wet film containing the light-controlling layer. Finally, the wet film of the light-controlling layer can be cross-linked and cured using an ultraviolet curing machine under a protective atmosphere such as nitrogen to obtain the aforementioned light valve device.

[0030] Furthermore, the present invention provides a dimming glass assembly comprising: a first glass plate, a second glass plate, and a light valve as described above disposed between the first glass plate and the second glass plate.

[0031] In some embodiments of the present invention, a first interlayer is preferably provided between the first glass plate and the light valve, and / or a second interlayer is preferably provided between the second glass plate and the light valve. The present invention embodiments can use conventional adhesive layers to assemble the dimming glass assembly.

[0032] Preferably, the first glass plate and the second glass plate are selected from at least one of inorganic glass and organic glass.

[0033] Preferably, the first glass plate and the second glass plate are selected from at least one of UV-blocking glass, IR-blocking glass, Low-E glass, tempered glass, and antibacterial glass.

[0034] Preferably, the first glass plate and the second glass plate are selected from colored glass such as gray glass and brown glass.

[0035] Preferably, the adhesive layer material is selected from at least one of EVA film (ethylene-vinyl acetate film), TPU film (thermoplastic polyurethane film), and PVB film (polyvinyl butyral).

[0036] Preferably, the adhesive layer material is selected from at least one of UV-blocking EVA film, UV-blocking TPU film, and UV-blocking PVB film.

[0037] Preferably, the adhesive layer material is selected from at least one of gray EVA film, gray TPU film, and gray PVB film.

[0038] There are no special restrictions on the method of manufacturing the dimming glass assembly. It can be any conventional lamination method for dimming glass assemblies in the field, such as lamination in a laminator, or lamination in an autoclave or lamination box / furnace.

[0039] In an embodiment of the present invention, the non-blue tone of the light valve is: in the CIELab color coordinate system, 5 < L < 40, -10 < a < 10, -10 < b < 10; preferably 10 < L < 30, -5 < a < 5, -5 < b < 5.

[0040] Compared with existing technologies, the light valve provided by this invention includes: a first transparent substrate, a first transparent electrode, a light-controlling layer, a second transparent electrode, and a second transparent substrate sequentially laminated together, with the first and second transparent electrodes disposed opposite to each other; the light-controlling layer includes a polymer matrix, in which suspended medium droplets are dispersed, and solid light-controlling particles are distributed within the suspended medium droplets; the solid light-controlling particles are a mixture of blue particles and yellow particles, wherein the blue particles are selected from polyiodine compound particles, and the yellow particles are selected from PbCrO4 particles; the light valve has a non-blue base color in the dark state and is transparent in the bright state. The light valve of this invention, based on a mixture of polyiodine compound particles and PbCrO4 particles, is simple to prepare and can conveniently and effectively modulate a non-blue dark base color and a transparent bright state, thus meeting people's needs for multiple colors. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0042] Figure 1The diagram shows the structure of a dimming film provided in some embodiments of the present invention; wherein, 1 is a transparent electrode, 2 is a light-controlling layer, 3 is a transparent substrate, 21 is a polymer matrix, 22 is a suspended medium droplet containing solid light-controlling particles, and 23 is a solid light-controlling particle, namely a mixture of blue and yellow particles of the present invention.

[0043] Figure 2 The GPC results for the preparation of the liquid suspension medium in Example 1 of the present invention;

[0044] Figure 3 The GPC results for preparing the organosilicon oil polymer matrix precursor with unsaturated bonds in Example 9 of the present invention are shown. Detailed Implementation

[0045] The technical solutions described below in the embodiments of this application are clearly and completely described. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0046] To better understand the technical content of this invention, specific embodiments are provided below to further illustrate the invention. Unless otherwise specified, the reagents and materials described in the following embodiments are commercially available.

[0047] Example 1: Preparation of Liquid Suspension Medium

[0048] 24.4 g of dodecyl methacrylate, 2.0 g of hydroxyethyl methacrylate, 2.3 g of 1-hexamethylene mercaptan, and 20 mL of toluene were added separately to 250 mL three-necked round-bottom glass flasks. A mechanical stirrer was installed in the center of each flask, a condenser was connected to one side, and a thermometer was placed on the other side connected to argon gas. Before heating, argon gas was passed through the flask for approximately 10 minutes to completely replace the air. The flask was then heated to 60 °C. At this temperature, 10 mL of toluene solution containing 0.20 g of azobisisobutyronitrile was added to the flask. The reaction temperature was maintained at 60 °C for 21 hours, then the temperature was increased, and the reaction solution was refluxed for 3 hours. The reaction was then stopped. The solution was then treated with a rotary evaporator at 100 °C for 3 hours to remove toluene and unreacted reactants, yielding a liquid suspension. GPC results are shown below. Figure 2 (Its peak value was 2476, and its dwell time was 7.772 minutes).

[0049] Example 2: Preparation of yellow solid light-controlling particles PbCrO4

[0050] Add 2.2 g of sodium dodecyl sulfate (SDS), 5 g of polyethylene glycol (PEG, average molecular weight 6000), 1.76 g of Na₂CrO₄·4H₂O, and 200 g of distilled water to a 500 mL Erlenmeyer flask, stir to dissolve, and label this solution A. Add 2.5 g of Pb(NO₃)₂ and 40 g of distilled water to a 250 mL Erlenmeyer flask, stir to dissolve, and label this solution B. Slowly add solution B to solution A while stirring rapidly, and continue stirring for 30 minutes. Then add the above mixed solution to a 500 mL hydrothermal reactor, stir at 200 rpm, react at 120 °C for 15 hours, allow to cool naturally, and open the hydrothermal reactor. Centrifuge the resulting reaction solution at 15000 g for 0.5 hours, discard the supernatant to remove unreacted raw materials; the bottom of the flask should contain a yellow product. Add distilled water to the centrifuge flask to fully disperse the resulting yellow solid. Centrifuge at 15000g for 0.5 hours, then discard the supernatant. Repeat this process three times to obtain yellow solid light-controlling particles 23. Disperse these solid light-controlling particles 23 thoroughly with 250 mL of isoamyl acetate for later use.

[0051] XRD characterization revealed that the yellow solid light-controlling particles were PbCrO4. SEM characterization showed that the particles had a length of 350 nm, a width of 60 nm, and an aspect ratio of 5.8.

[0052] Add 40 g of DOIP (di(2-ethylhexyl) isophthalate) to a 250 mL round-bottom glass flask, and then add the prepared yellow solid light-controlling particles in batches along with an isoamyl acetate dispersion. Remove the isoamyl acetate using a rotary evaporator, and finally continue processing at 80 °C using a rotary evaporator for 3 hours. Weigh the particles and calculate their mass. Then add an appropriate amount of DOIP and mix thoroughly to achieve a solid light-controlling particle / DOIP weight ratio of 1 / 12. The resulting suspension containing the yellow solid light-controlling particles is called LCP-2.

[0053] Example 3: Preparation of yellow solid light-controlling particles PbCrO4

[0054] Same as Example 2, except that 1.41 g of hexadecyltrimethylammonium bromide (CTAB) was used instead of 2.2 g of sodium dodecyl sulfate (SDS), and the reaction was carried out at 150°C for 15 hours.

[0055] XRD characterization results show that the yellow solid light-controlling particles are PbCrO4. SEM characterization results show that the yellow solid light-controlling particles have a length of 410 nm, a width of 50 nm, and an aspect ratio of 8.2.

[0056] Add 40 g of the liquid suspension medium prepared in Example 1 to a 250 mL round-bottom glass flask, and add the isoamyl acetate dispersion of the yellow solid light-controlling particles prepared above in batches. Remove the isoamyl acetate using a rotary evaporator, and finally continue processing at 80 °C using a rotary evaporator for 3 hours. After weighing, calculate the mass of the solid light-controlling particles, and then add an appropriate amount of the liquid suspension medium prepared in Example 1, mix thoroughly, and make the weight ratio of solid light-controlling particles to liquid suspension medium = 1 / 12. The resulting suspension containing yellow solid light-controlling particles is called LCP-3.

[0057] Example 4: Preparation of yellow solid light-controlling particles PbCrO4

[0058] Same as Example 2, except that 3 grams of sodium dodecylbenzenesulfonate (SDBS) were used instead of 2.2 grams of sodium dodecyl sulfate (SDS), and the reaction was carried out at 100°C for 15 hours.

[0059] XRD characterization results show that the yellow solid light-controlling particles are PbCrO4. SEM characterization results show that the yellow solid light-controlling particles have a length of 200 nm, a width of 40 nm, and an aspect ratio of 5.

[0060] Add 40 g of the liquid suspension medium prepared in Example 1 to a 250 mL round-bottom glass flask, and then add the isoamyl acetate dispersion of the yellow solid light-controlling particles prepared above in batches. Remove the isoamyl acetate using a rotary evaporator, and finally continue processing at 80 °C using a rotary evaporator for 3 hours. After weighing, calculate the mass of the solid light-controlling particles, and then add an appropriate amount of the liquid suspension medium prepared in Example 1, mix thoroughly, and make the weight ratio of solid light-controlling particles to liquid suspension medium = 1 / 12. The resulting suspension containing yellow solid light-controlling particles is called LCP-4.

[0061] Example 5: Preparation of yellow solid light-controlling particles PbCrO4

[0062] Same as Example 2, except that 1.1 g of sodium dodecyl sulfate (SDS) was used and the reaction was carried out at 80°C for 20 hours.

[0063] XRD characterization results show that the yellow solid light-controlling particles are PbCrO4. SEM characterization results show that the yellow solid light-controlling particles have a length of 500 nm, a width of 50 nm, and an aspect ratio of 10.

[0064] Add 40 g of TOTM (tris(2-ethylhexyl) trimellitate) to a 250 mL round-bottom glass flask, and then add the prepared yellow solid light-controlling particles in batches along with an isoamyl acetate dispersion. Remove the isoamyl acetate using a rotary evaporator, and finally continue processing at 80 °C using a rotary evaporator for 3 hours. Weigh the particles and calculate their mass. Then add an appropriate amount of TOTM and mix thoroughly to achieve a solid light-controlling particle / TOTM weight ratio of 1 / 12. The resulting suspension containing the yellow solid light-controlling particles is called LCP-5.

[0065] Preparation of yellow solid light-controlling particles PbCrQ4 by reverse step 6

[0066] Same as Example 2, except that 4 grams of polyethylene glycol (PEG, average molecular weight 400) were used instead of 5 grams of polyethylene glycol (PEG, average molecular weight 6000), and the reaction was carried out at 100°C for 20 hours.

[0067] XRD characterization results show that the yellow solid light-controlling particles are PbCrO4. SEM characterization results show that the yellow solid light-controlling particles have a length of 450 nm, a width of 60 nm, and an aspect ratio of 7.5.

[0068] Add 40 g of epoxidized soybean oil (product number: S1179, manufactured by Spectrum Chemical) to a 250 mL round-bottom glass flask, and add the prepared yellow solid light-controlling particles in batches along with an isoamyl acetate dispersion. Remove the isoamyl acetate using a rotary evaporator, and then continue processing at 80 °C using a rotary evaporator for 3 hours. Weigh the particles and calculate their mass. Then add an appropriate amount of epoxidized soybean oil and mix thoroughly to achieve a solid light-controlling particle / epoxidized soybean oil weight ratio of 1 / 12. The resulting suspension containing the yellow solid light-controlling particles is called LCP-6.

[0069] Example 7: Preparation of yellow solid light-controlling particles PbCrO4

[0070] Same as Example 2, except that 2.5 g of polyethylene glycol (PEG, average molecular weight 3350) was used instead of 5 g of polyethylene glycol (PEG, average molecular weight 6000), and the reaction was carried out at 100°C for 20 hours.

[0071] XRD characterization results show that the yellow solid light-controlling particles are PbCrO4. SEM characterization results show that the yellow solid light-controlling particles have a length of 550 nm, a width of 60 nm, and an aspect ratio of 9.2.

[0072] Add 40 g of TOTM (tris(2-ethylhexyl) trimellitate) to a 250 mL round-bottom glass flask, and then add the prepared yellow solid light-controlling particles in batches along with an isoamyl acetate dispersion. Remove the isoamyl acetate using a rotary evaporator, and finally continue processing at 80 °C using a rotary evaporator for 3 hours. Weigh the particles and calculate their mass. Then add an appropriate amount of TOTM and mix thoroughly to achieve a solid light-controlling particle / TOTM weight ratio of 1 / 12. The resulting suspension containing the yellow solid light-controlling particles is called LCP-7.

[0073] Example 8: Preparation of Blue Solid Light-Controlling Particles

[0074] Add 30g of isoamyl acetate solution containing 21.2wt% nitrocellulose (SS 1 / 4sec), 6g of I2, 70g of isoamyl acetate, and 4g of anhydrous CaI2 to a 250mL three-necked round-bottom glass flask, and heat to 42℃. After the I2 dissolves, add 6g of anhydrous methanol, 0.8g of distilled water, and 4g of 2,5-pyrazine dicarboxylic acid dihydrate to the flask, and heat and stir at 42℃ for 4 hours, then allow to cool naturally. Centrifuge the resulting reaction solution at 1350g for 0.5 hours to remove large particles, then centrifuge the supernatant at 18000g for 5 hours, discard the supernatant, and obtain blue solid light-controlling particles 23. Disperse these solid light-controlling particles 23 thoroughly with 250mL of isoamyl acetate for later use.

[0075] SEM characterization results show that the blue solid light-controlling particles have a length of 280 nm, a width of 70 nm, and an aspect ratio of 4.

[0076] Add 40 g of the liquid suspension medium prepared in Example 1 to a 250 mL round-bottom glass flask, and add the isoamyl acetate dispersion of the blue solid light-controlling particles prepared above in batches. Remove the isoamyl acetate using a rotary evaporator, and finally continue processing at 80 °C using a rotary evaporator for 3 hours. After weighing, calculate the mass of the solid light-controlling particles, and then add an appropriate amount of the liquid suspension medium prepared in Example 1, mix thoroughly, and make the weight ratio of solid light-controlling particles to liquid suspension medium = 1 / 12. The resulting suspension containing blue solid light-controlling particles is called LCP-8.

[0077] Example 9: Preparation of an organosilicon oil polymer matrix precursor with unsaturated bonds

[0078] Add 108g of hydroxyl-terminated dimethyldiphenylpolysiloxane and 380mL of n-heptane to a 1L three-necked round-bottom glass flask. Connect a water separator to one side of the flask, which is then connected to a condenser. Install a mechanical stirrer in the middle, and place a thermometer on the other side. Heat the reaction mixture in the flask to reflux for 30 minutes. When a small amount of water appears in the water separator, add a solution of 0.26g of stannous octoate dissolved in 20mL of n-heptane. Then add 6g of 3-acryloyloxypropyltrimethoxysilane dropwise over approximately 5 minutes. Initiate the condensation reaction for 2 hours, then immediately add 60mL of trimethylmethoxysilane as a reaction terminator. Terminate the reaction by continuing for 2 hours, then rapidly cool to room temperature. Mix 100mL of ethanol with the cooled reaction mixture in a 2L beaker, stirring. Rinse the reaction flask with 60mL of heptane and pour the rinsings into the beaker. After thorough mixing, add 400mL of methanol and stir for 15 minutes. The resulting mixture was poured into a 2L separatory funnel and allowed to stand for several hours until stratification occurred. The lower layer was removed and then treated in a rotary evaporator at 70°C for 3 hours to remove low-boiling-point substances, ultimately yielding an organosilicon oil with unsaturated bonds, i.e., the polymer matrix precursor. GPC results are shown in [Figure number missing]. Figure 3 (Its peak value was 31,173, and its dwell time was 6.720 minutes).

[0079] Example 10: Preparation of a dimming film

[0080] 0.03 g of photoinitiator 819, 1.0 g of a mixture of liquid suspension medium LCP-2 containing solid light-controlling particles 23 prepared in Example 2, 2.0 g of a mixture of liquid suspension medium LCP-8 containing solid light-controlling particles 23 prepared in Example 8, and 7.0 g of an organosilicon oil polymer matrix precursor with unsaturated bonds prepared in Example 9 were mixed evenly to obtain a light-controlling layer matrix emulsion. The weight ratio of LCP-2 to LCP-8 was 0.5:1.

[0081] The light-controlling layer matrix emulsion was coated onto an ITO / PET transparent conductive film (sheet resistance 150 Ω / □, visible light transmittance 88%, haze 1.5) using a doctor blade type automatic coating machine (MSK-AFA-III, MTI Corporation) to a thickness of 80 micrometers. Another ITO / PET transparent conductive film was then coated onto the wet film of the light-controlling layer matrix emulsion, resulting in a wet film containing the light-controlling layer. The film was then cured for 1 minute under a nitrogen atmosphere using an Aventk X200-150 UV curing machine at a UV power of 700 W / m. 2 This yields the dimming film.

[0082] In this embodiment, a transparent conductive film (transparent electrode) is formed on a plastic sheet substrate.

[0083] The transmittance Lab value of the dimming film was tested using an UltraScan VIS colorimeter. The total light transmittance of the dimming film was measured using a Linshang Technology LS171.

[0084] Toff indicates that no electric field is applied to the dimming film, while Ton indicates that 220V AC current is applied between the two electrodes of the dimming film.

[0085] The specific results are shown in Table 1.

[0086] Example 11 Preparation of dimming film

[0087] Same as Example 10, except that the 1.0 g LCP-2 prepared in Example 2 is replaced with 1.2 g LCP-3 prepared in Example 3, and the LCP-8 is 1.8 g. The weight ratio of LCP-3 to LCP-8 is 0.7:1. The ITO / PET transparent conductive film contains an organosilicon resin adhesive layer.

[0088] Example 12 Preparation of dimming film

[0089] Same as Example 10, except that the 1.0 g LCP-2 prepared in Example 2 is replaced with 1.5 g LCP-4 prepared in Example 4, and the LCP-8 is 1.5 g. The weight ratio of LCP-4 to LCP-8 is 1:1.

[0090] Example 13 Preparation of dimming film

[0091] Same as Example 10, except that the 1.0 g LCP-2 prepared in Example 2 is replaced with 2.0 g LCP-5 prepared in Example 5, and the LCP-8 is 1.0 g. The weight ratio of LCP-5 to LCP-8 is 2:1.

[0092] Example 14 Preparation of dimming film

[0093] Same as Example 10, except that the 1.0 g LCP-2 prepared in Example 2 was replaced with 1.8 g LCP-6 prepared in Example 6, and the LCP-8 was 1.2 g. The weight ratio of LCP-6 to LCP-8 was 1.5:1.

[0094] Example 15 Preparation of dimming film

[0095] Same as Example 10, except that the 1.0 g LCP-2 prepared in Example 2 was replaced with 1.65 g LCP-7 prepared in Example 7, and the LCP-8 was 1.35 g. The weight ratio of LCP-7 to LCP-8 was 1.2:1.

[0096] Comparative Example 1: Preparation of a dimming film

[0097] Same as Example 10, except that the LCP-2 prepared in Example 2 was not included, and the LCP-8 prepared in Example 8 was 3 grams.

[0098] Comparative Example 2: Preparation of dimming film

[0099] Same as Example 10, except that the LCP-8 prepared in Example 8 was not included, and the LCP-2 prepared in Example 2 was 3 grams.

[0100] Table 1. Transmission Lab values ​​of the dimming film in the embodiments of the present invention.

[0101]

[0102]

[0103] In Table 1, Toff indicates that no electric field is applied to the dimming film, and Ton indicates that 220V AC current is applied between the two electrodes of the dimming film.

[0104] A comparison of Examples 10-15 and Comparative Examples 1-2 shows that in Comparative Example 1, when no electric field is applied to the dimming film, b is -25.1, exhibiting a typical blue color. In Comparative Example 2, when no electric field is applied to the dimming film, b is 26.8, exhibiting a typical yellow color. However, this invention, through the control of different proportions of yellow and blue light-controlling particles, allows the dimming film, when no electric field is applied (Examples 10-15), to exhibit a grayish color range where -10 < a < 10 and -10 < b < 10. It is evident that in conventional technologies, the suspended particle light valve exhibits a monotonous, cool blue color in the dark state. In contrast, this invention, through the control of different proportions of specific yellow and blue light-controlling particles, allows the light valve to exhibit a neutral gray or other non-blue color in the dark state, thus satisfying people's demand for a rich variety of colors and possessing significant importance.

[0105] The invention has been described above using a light valve, i.e., a dimming film, with a transparent plastic sheet as the substrate as an example. Clearly, the concept of this invention is also fully applicable to light valves with a glass substrate, i.e., dimming glass.

[0106] The descriptions of the above embodiments are merely illustrative of the methods and core ideas of the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A light valve, characterized by Comprise: The first transparent substrate, the first transparent electrode, the light control layer, the second transparent electrode and the second transparent substrate are sequentially compounded, the first transparent electrode and the second transparent electrode are oppositely arranged; the light control layer comprises a polymer matrix, the polymer matrix is interspersed with suspension medium droplets, and solid light control particles are distributed in the suspension medium droplets; The solid light control particles are a mixture of blue particles and yellow particles, the blue particles are selected from polyiodide compound particles, and the yellow particles are selected from PbCrO4 particles; The dark state of the light valve is a non-blue tone, and the bright state is transparent.

2. A light valve according to claim 1, characterized in that The particle length of the solid light control particles is 50-800 nm, and the aspect ratio between the particle length and the particle width is 2-30.

3. A light valve according to claim 1, characterized in that The mass ratio of the yellow particles to the blue particles is (0.5-2):

1.

4. A light valve according to any one of claims 1-3, characterized in that The non-blue tone is in the CIELab color coordinate, 5 5. A light valve according to claim 4, characterized in that The non-blue tone is in the CIELab color coordinate, 10 6. A light valve according to any one of claims 1-3, characterized in that The polymer matrix is formed by cross-linking and curing of an organic silicone oil polymer matrix precursor having unsaturated bonds; the material forming the suspension medium droplets is selected from at least one of fluorocarbon organic compounds, phthalate esters, trimellitate esters, dodecylbenzene, polybutene oil, polyacrylate, polymethacrylate, epoxy soybean oil, and epoxy linseed oil.

7. A light valve according to any one of claims 1-3, characterized in that The first transparent substrate and the second transparent substrate are glass plates, or the first transparent substrate and the second transparent substrate are transparent plastic sheets.

8. A light valve according to any one of claims 1-3, characterized in that The first transparent electrode and the second transparent electrode are each independently selected from ITO conductive layers, FZO conductive layers, IZO conductive layers, GZO conductive layers, AZO conductive layers, PEDOT conductive layers, nano-Ag wire conductive layers, conductive graphene, and nano-Cu wire conductive layers.

9. A light valve according to any one of claims 1-3, characterized in that The first transparent electrode and / or the second transparent electrode is covered with an adhesive layer; the material of the adhesive layer comprises at least one of epoxy resin, polyurethane, polyimide resin, polystyrene resin, acrylic resin, modified acrylic acid, and silicone resin.

10. A method of manufacturing the light valve as claimed in any one of claims 1-9, characterized in that, Comprise: Mixing solid light control particles with suspension medium to form a mixture containing solid light control particles; mixing a polymer matrix precursor, an initiator for initiating cross-linking and curing of the polymer matrix precursor, and the mixture containing solid light control particles to obtain a light control layer matrix emulsion; Coating the above light control layer matrix emulsion on the first transparent electrode of the first transparent substrate to form a light control layer wet film; Covering the second transparent electrode on the second transparent substrate on the light control layer wet film, and cross-linking and curing the light control layer wet film to obtain the light valve.

11. A light control glass assembly, characterized by Comprise: a first glass plate and a second glass plate, And, the light valve as claimed in any one of claims 1-9 is arranged between the first glass plate and the second glass plate.

12. The dimmable glazing assembly of claim 11, wherein, A first interlayer is arranged between the first glass plate and the light valve, and / or a second interlayer is arranged between the second glass plate and the light valve.

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