A light valve, a method of manufacturing a light valve, and a light control glass assembly having light resistance stability

Abstract

The application provides a light valve, a light valve preparation method and a light-adjustable glass assembly with light resistance. By introducing a methacrylate monomer and / or an acrylic ester monomer with a conjugated pi electron system structure functional group, a macromolecular copolymer is prepared by a heating polymerization method, a suspension medium with a unique structure is formed, the light resistance functional monomer is more uniformly distributed, the macromolecular structure of the copolymer makes the chemical state of the light resistance functional group more stable, meanwhile, the physical distribution state and the chemical stable state of the light control particles are double protected, so that the light resistance stability of the light-adjustable glass assembly is significantly improved, the service life is prolonged, meanwhile, the processing performance of the material is also improved, and the actual use demand can be met.

Description

Technical Field

[0001] This invention relates to the field of electronic light control materials, and particularly to a light valve, a method for preparing the light valve, and a dimming glass assembly with anti-light stability. Background Technology

[0002] A light valve is an electronic light-controlling device that primarily consists of a light-controlling layer placed between two transparent conductive films. When an electric field is applied, the arrangement or state of the materials in the light-controlling layer changes, thereby altering the light transmission characteristics of the device, such as switching from low to high transmittance or vice versa. Through the action of the electric field, rapid transitions between the on and off states can be achieved. Based on different light-controlling mechanisms, light valves can be classified into suspended particle light valves, polymer-dispersed liquid crystal light valves, and electrochemical reaction light valves, among others.

[0003] Depending on the substrate of the light valve, it can be made of plastic sheet such as PET, generally referred to as a dimming film; or it can be made of glass, generally referred to as dimming glass. The assembly formed by laminating the dimming film is generally called a dimming glass assembly.

[0004] In practical use, dimming films, dimming glass, and dimming glass assemblies are often exposed to external light sources such as sunlight, and the ultraviolet rays in sunlight have a serious destructive effect on them. Therefore, the UV aging resistance of dimming films, dimming glass, and dimming glass assemblies is particularly important. However, the UV aging resistance of previous dimming films was inadequate, which often required the use of additional UV blocking equipment in practical applications, such as the additional use of UV-blocking films during the manufacturing of dimming glass assemblies. This not only increases the manufacturing cost of dimming glass assemblies but also limits the application of dimming films, dimming glass, and dimming glass assemblies.

[0005] Therefore, for existing dimming films, there is an urgent need to solve the problem of poor resistance to photoaging.

[0006] CN111253875B discloses an EVA interlayer for electrically controlled dimming glass and its preparation method. The interlayer comprises a three-layer structure of EVA / POE / EVA co-extruded composite. During the preparation process, a small amount of ultraviolet absorber is added to both the POE and EVA layers to improve their anti-light performance. The finished product is obtained by mechanical mixing and extrusion molding.

[0007] Based on a method for preparing a light valve, the inventors of this patent have creatively introduced a specific type of acrylate monomer with a conjugated π electronic system structure. Through heating polymerization, a specific type of macromolecular copolymer with a conjugated π electronic system structure is prepared to form a suspension medium with a unique structure. The anti-light functional monomers are more evenly distributed, and the macromolecular structure of the copolymer makes the chemical state of the anti-light functional groups more stable. At the same time, it improves the dual protection of the physical distribution state and chemical stability state of the light-controlling particles, thereby significantly improving the anti-light stability of the dimming glass component, extending its service life, and improving the processing performance of the material to meet the actual use requirements. Summary of the Invention

[0008] Based on the invention of a light valve and its preparation method, the inventors further improved the polymer composition of the suspension medium to enhance its light resistance.

[0009] A first aspect of the present invention provides a light valve, comprising:

[0010] First transparent substrate,

[0011] The first transparent electrode is formed on the first transparent substrate.

[0012] Second transparent substrate,

[0013] The second transparent electrode is formed on the second transparent substrate.

[0014] The first transparent electrode and the second transparent electrode are arranged opposite to each other, and

[0015] A light-controlling layer is disposed between the first transparent electrode and the second transparent electrode; the light-controlling layer comprises a polymer matrix;

[0016] The polymer matrix contains suspended medium droplets, and solid light-controlling particles are distributed within the suspended medium droplets.

[0017] The suspension medium is obtained from at least one acrylate copolymer, which is obtained by copolymerizing monomers containing the following units under the action of a copolymerization catalyst:

[0018] (a) is selected from alkyl acrylate monomers.

[0019] (b) Selected from hydroxy acrylate monomers, and

[0020] (c) An acrylate monomer having a conjugated π-electron system structure, having the following structural formula:

[0021]

[0022] in,

[0023] R is H or CH3.

[0024] X is a group having a conjugated π-electron structure and contains at least one of an ortho-hydroxyphenyl substituent, a nitrogen-containing heterocyclic substituent, or a carbonylbenzene ring substituent, which may be further optionally substituted.

[0025] Furthermore, the proportions of the monomers forming units (a), (b), and (c) of the acrylate copolymer are as follows: assuming a total mass of 100 parts, the proportion of monomer (a) in unit (a) is 50-95 parts by mass, the proportion of monomer (b) in unit (b) is 2-30 parts by mass, and the proportion of monomer (c) in unit (c) is 3-20 parts by mass.

[0026] Furthermore, the peak molecular weight of the acrylate copolymer is 2000-7000.

[0027] Furthermore, the monomer copolymerization catalyst for forming the (a), (b), and (c) units of the acrylate copolymer is a thermally initiated free radical catalyst, preferably at least one of the following: azo initiator (azobisisobutyronitrile (AIBN), azobisisoheptanenitrile (ABVN), dimethyl azobisisobutyrate (AIBME), azobisisobutyramidine hydrochloride (AIBA), azobisisobutyramidine imidazoline hydrochloride (AIBI), etc.), hydrogenated tributyltin (n-Bu3SnH) / AIBN, and ammonium persulfate.

[0028] Furthermore, the suspension medium also includes a non-conductive liquid, which is selected from at least one of fluorocarbon organic compounds, phthalates, triterpenes, dodecylbenzene, polybutene oil, epoxidized soybean oil, and epoxidized linseed oil;

[0029] Furthermore, the solid light-controlling particles are selected from one or more of oxide nanorods, perovskite nanorods, and polyiodine compound nanorods; the particle length of the solid light-controlling particles is 50-800 nm; and the aspect ratio of the solid light-controlling particles is 2-30.

[0030] Furthermore, the mass ratio of the total mass of the suspended medium and the solid light-controlling particles to the polymer matrix is ​​1:(1-10); the mass ratio of the acrylate copolymer in the suspended medium to the total mass of the suspended medium is 1:(1-5); and the mass ratio of the suspended medium to the solid light-controlling particles is 1:(0.05-0.2).

[0031] The present invention also provides an acrylate copolymer comprising monomers of units (a), (b), and (c); wherein the monomer of unit (a) is selected from alkyl acrylate monomers; the monomer of unit (b) is selected from hydroxy acrylate monomers; and the monomer of unit (c) is selected from acrylate monomers having a conjugated π-electron structure. The proportions of the monomers forming units (a), (b), and (c) of the acrylate copolymer are as follows: assuming a total mass of 100 parts, the proportion of monomer (a) in unit (a) is 50–95 parts by mass, the proportion of monomer (b) in unit (b) is 2–30 parts by mass, and the proportion of monomer (c) in unit (c) is 3–20 parts by mass.

[0032] The present invention also provides a method for preparing an acrylate copolymer, comprising:

[0033] In a protective atmosphere, monomers of units (a), (b), and (c), a molecular weight regulator, a free radical polymerization initiator, and a solvent are mixed and heated to carry out a polymerization reaction to obtain an acrylate copolymer. The proportions of monomers in units (a), (b), and (c) are as follows: assuming a total mass of 100 parts, monomer (a) accounts for 50–95 parts by mass, monomer (b) accounts for 2–30 parts by mass, and monomer (c) accounts for 3–20 parts by mass.

[0034] Preferably, the molecular weight regulator is a thiol compound; the thiol compound is selected from thiothiols; the mass of the molecular weight regulator is 5% to 10% of the monomer mass of unit (a);

[0035] The free radical polymerization initiator is selected from thermally initiated free radical catalysts, preferably at least one of azo initiators (azobisisobutyronitrile (AIBN), azobisisoheptanenitrile (ABVN), dimethyl azobisisobutyrate (AIBME), azobisisobutyramidine hydrochloride (AIBA), azobisisobutyramidine imidazoline hydrochloride (AIBI), etc.), hydrogenated tributyltin (n-Bu3SnH) / AIBN, and ammonium persulfate. The mass of the free radical polymerization initiator is 0.5% to 1% of the monomer mass of unit (a);

[0036] The polymerization reaction specifically involves heating to 40°C–100°C and reacting for 15–50 hours, followed by continued heating to reflux and maintaining reflux for 1–5 hours.

[0037] The protective gas is a non-oxidizing inert gas, selected from at least one of nitrogen, argon, and helium.

[0038] The solvent is selected from liquids containing benzene rings such as toluene, ethylbenzene, and xylene, or ester liquids such as ethyl acetate.

[0039] Furthermore, the polymer matrix is ​​formed by cross-linking and curing an organosilicon oil polymer matrix precursor with unsaturated bonds.

[0040] Furthermore, the polymer matrix precursor is (meth)acryloyloxy modified silicone oil, specifically acryloyloxy modified silicone oil in the embodiments of the present invention; the type of polymer matrix precursor can be selected according to actual needs, and there are no special limitations.

[0041] Furthermore, the first transparent substrate and the second transparent substrate are glass plates.

[0042] Furthermore, the first transparent substrate and the second transparent substrate are transparent plastic sheets.

[0043] Furthermore, the first transparent electrode and the second transparent electrode are each independently selected from ITO conductive layer, FZO conductive layer, IZO conductive layer, GZO conductive layer, AZO conductive layer, PEDOT conductive layer, nano Ag wire conductive layer, conductive graphene and nano Cu wire conductive layer.

[0044] Furthermore, the first transparent electrode and / or the second transparent electrode are covered with an adhesive layer, the adhesive layer material including at least one of epoxy resin, polyurethane, polyimide resin, polystyrene resin, acrylic resin, modified acrylic resin and silicone resin.

[0045] In a second aspect of the invention, a method for preparing the above-mentioned optical valve is provided, comprising:

[0046] Provides solid-state light-controlling particles;

[0047] Provide a suspension medium;

[0048] The solid light-controlling particles are mixed with the suspension medium to form a mixture containing the solid light-controlling particles in the suspension medium;

[0049] Provide polymer matrix precursors;

[0050] The initiator that initiates the crosslinking and curing of the polymer matrix precursor, the mixture of the suspension medium containing solid light-controlling particles, and the polymer matrix precursor are mixed to obtain a light-controlling layer matrix emulsion.

[0051] The above-mentioned light-controlling layer matrix emulsion is coated onto the first transparent electrode of the first transparent substrate to form a light-controlling layer wet film;

[0052] The second transparent electrode on the second transparent substrate is covered onto the wet film of the light-controlling layer; and

[0053] The light control layer wet film is cross-linked and cured to obtain the light valve device.

[0054] In a third aspect of the invention, a dimming glass assembly with anti-light stability is provided, comprising a first glass plate and a second glass plate, and the aforementioned light valve disposed between the first glass plate and the second glass plate.

[0055] Furthermore, a first interlayer is provided between the first glass plate and the light valve, and / or a second interlayer is provided between the second glass plate and the light valve.

[0056] In this invention, there are no special restrictions on the types of the first and second glass plates. They can be transparent glass commonly used in dimming glass components that are well known to those skilled in the art. They can be ordinary glass such as inorganic glass or organic glass, or functional glass such as UV blocking glass, IR blocking glass, Low-E glass, tempered glass or antibacterial glass, etc. They can also be selected from colored glass such as gray glass or brown glass.

[0057] In this invention, there are no special restrictions on the types of the first and second interlayers. They can be conventional interlayers for dimming glass components that are well known to those skilled in the art. They can be EVA films, TPU films, PVB films, or functional films, such as UV-blocking EVA films, UV-blocking TPU films, UV-blocking PVB films, etc. They can also be films with a certain color, such as gray EVA films, gray TPU films, gray PVB films, etc.

[0058] In this invention, 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 art, such as lamination in a laminator, or lamination in an autoclave or lamination box / furnace.

[0059] In this invention, the suspension medium of the light valve is obtained from at least one acrylate copolymer. The acrylate copolymer contains an acrylate monomer with a conjugated π-electron structure in unit (c), and contains at least one of an ortho-hydroxyphenyl substituent, a nitrogen-containing heterocyclic substituent, or a carbonylbenzene ring substituent. Compared to acrylate copolymers without unit (c), the acrylate copolymer containing unit (c) tends to absorb ultraviolet radiation in the wavelength range of 280–400 nm. Simultaneously, the acrylate copolymer suspension medium, generated by introducing an acrylate monomer with a special functional group (c) to participate in the polymerization reaction, provides dual protection for the physical distribution and chemical stability of the light-controlling particles, ultimately significantly improving the stability of the light valve and its components under light irradiation conditions, extending the service life of the dimming glass, and also enhancing the material's processability. Attached Figure Description

[0060] 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. The drawings described below are merely embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0061] Figure 1 This is a schematic diagram of the structure of a dimming film provided in some embodiments of the present invention. In the diagram, 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.

[0062] Figure 2 The GPC results for the preparation of acrylate copolymers in Example 3 of the present invention are shown. Detailed Implementation

[0063] the term

[0064] In this invention, the following terms have the meanings defined below.

[0065] Light valve:

[0066] A light valve is an electronic light control device. It mainly consists of a light control layer between two transparent conductive films. When an electric field is applied, the arrangement or state of the materials in the light control layer changes, thereby changing the light transmission characteristics of the device, such as changing from low light transmittance to high light transmittance, or from high light transmittance to low light transmittance.

[0067] Crosslinking:

[0068] Crosslinking refers to the polymerization reaction of active groups on the side chains of unit monomers in a polymer matrix precursor. These side chains are structures covalently linked to silicon atoms, excluding silanol groups and groups capable of forming silanol groups. In this text, crosslinking is sometimes also referred to as crosslinking curing, which occurs under thermocatalytic or irradiation-catalytic conditions, such as by adding a photoinitiator to the polymer matrix precursor to induce polymerization through irradiation.

[0069] Alkyl acrylate monomers:

[0070] The monomer unit (a) that forms the acrylate copolymer has the following chemical formula:

[0071] CH2=CR1COO-R1' (Equation (1))

[0072] Where R1 is CH3 or H; R1' is C n H 2n+1 n is an integer from 1 to 18.

[0073] hydroxy acrylate monomers:

[0074] The monomer unit (b) that forms the acrylate copolymer has the following chemical formula:

[0075] CH2=CR2COO-R2' (Equation 2)

[0076] Where R2 is CH3 or H; R2' is C q H 2q -OH, where q is an integer from 1 to 8.

[0077] Silicone oil:

[0078] Linear polysiloxanes that remain in a liquid state at room temperature.

[0079] In this article, the suspension medium is sometimes also referred to as a liquid suspension medium.

[0080] The suspension medium in this invention is composed of at least one acrylate copolymer. When the suspension medium is composed of only one acrylate copolymer, the terms acrylate copolymer and suspension medium are equivalent.

[0081] This invention provides a light valve that significantly improves its light resistance stability. It utilizes an acrylate monomer with specific functional groups, followed by heating and polymerization to form an acrylate copolymer. A suspension medium containing this acrylate copolymer effectively solves the problem of poor stability of the light-adjusting film under illumination. Specifically, this invention effectively improves light resistance stability compared to materials without unit (c) by employing unit (c) of the following structural formula (A): an acrylate monomer with a conjugated π-electron structure, and containing at least one of an ortho-hydroxyphenyl substituent, a nitrogen-containing heterocyclic substituent, or a carbonylbenzene ring substituent.

[0082]

[0083] See Figure 1 Unit (c) comprises an acrylate monomer with specific functional groups containing functional groups that can eliminate free radicals generated by light exposure and improve light resistance. This monomer undergoes a heating polymerization reaction to form an acrylate copolymer, and a suspension medium 22 containing the acrylate copolymer. The suspension medium 22 is dispersed in the polymer matrix 21 in the form of droplets.

[0084] To better illustrate the present invention, the following specific embodiments are provided, including various preparation embodiments (including the preparation of solid light-controlling particles, the preparation of polymer matrix precursors, the preparation of liquid suspension media, and the preparation of dimming films) and light stability testing embodiments.

[0085] Example 1 Preparation of solid light-controlling particles

[0086] 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 0.5h to remove large particles, then centrifuge the supernatant at 18000g for 5h, discard the supernatant, and obtain solid light-controlling particles 23. Disperse these solid light-controlling particles 23 thoroughly with 250mL of isoamyl acetate.

[0087] Example 2 Preparation of polymer matrix

[0088] Add the following to a 500 mL three-necked round-bottom glass flask: 54 g of a silicon-containing non-crosslinked oligomer, hydroxyl-terminated dimethyldiphenyl polysiloxane, and 190 mL of n-heptane. Connect a water separator to one side of the flask, which is then connected to a condenser. Place a mechanical stirrer in the center and a thermometer on the other side. Heat the reaction mixture in the flask to reflux for 30 min, then add a solution of 0.13 g of stannous octoate dissolved in 10 mL of n-heptane. Then, add the silicon-containing crosslinkable monomer: 3 g of hydrolyzed 3-acryloyloxypropylmethyldimethoxysilane dropwise over approximately 5 minutes. React under reflux for 2 hours, then immediately add 30 mL of trimethylmethoxysilane as a reaction terminator; terminate the reaction by continuing for 2 hours, then rapidly cool to room temperature. Mix 50 mL of ethanol with the cooled reaction mixture in a 1 L beaker, then rinse the reaction flask with 30 mL of heptane and pour the rinsings into the beaker. After thorough mixing, add 200 mL of methanol and stir for 15 min. The resulting mixture was poured into a 1L 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 the siloxane copolymer.

[0089] Hydrolysis reaction: A condenser was attached to one side of a three-necked round-bottom glass flask, a mechanical stirrer was installed in the middle, and a thermometer was placed on the other side. In a 250 mL three-necked round-bottom glass flask, 0.1 g acetic acid, 5.5 g water, 44.5 g 3-acryloyloxypropylmethyldimethoxysilane, and 35 mL anhydrous ethanol were added sequentially. The hydrolysis reaction was controlled at 65 °C and carried out for 5 hours. After the reaction was completed, the solvent, residual water, and acid were removed using a rotary evaporator to obtain the hydrolysis product.

[0090] Example 3: Preparation of Liquid Suspension Medium

[0091] 24.4 g of dodecyl methacrylate (a), 2.0 g of hydroxyethyl methacrylate (b), 2.0 g of 2-hydroxybenzophenone methacrylate (c), 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 2351, and the dwell time was 7.793 minutes.

[0092] Add 40 g of the obtained suspension medium to a 250 mL round-bottom glass flask, and add the isoamyl acetate dispersion of solid light-controlling particles 23 prepared in Example 1 in batches. Remove the isoamyl acetate by rotary evaporator, and finally continue to treat at 80 °C using a rotary evaporator for 3 hours to obtain a mixture of liquid suspension medium containing solid light-controlling particles 23.

[0093] Example 4 Preparation of liquid suspension media

[0094] Same as Example 3, except that unit (c) 2-hydroxybenzophenone methacrylate is replaced with the monomers shown in Table 1.

[0095] Example 5 Preparation of liquid suspension media

[0096] Same as Example 3, except that unit (c) 2-hydroxybenzophenone methacrylate is replaced with the monomers shown in Table 1.

[0097] Example 6 Preparation of liquid suspension media

[0098] Same as Example 3, except that unit (a) dodecyl methacrylate is replaced with dodecyl acrylate;

[0099] Meanwhile, unit (c) 2-hydroxybenzophenone methacrylate was replaced with the monomers shown in Table 1.

[0100] Example 7 Preparation of liquid suspension media

[0101] Same as Example 6, except that unit (c) is replaced with a monomer as shown in Table 1.

[0102] Example 8 Preparation of liquid suspension media

[0103] Same as Example 6, except that unit (c) is replaced with a monomer as shown in Table 1.

[0104] Example 9 Preparation of liquid suspension media

[0105] Same as Example 6, except that unit (c) is replaced with a monomer as shown in Table 1.

[0106] Example 10 Preparation of liquid suspension media

[0107] Same as Example 6, except that unit (c) is replaced with a monomer as shown in Table 1.

[0108] Example 11 Preparation of liquid suspension media

[0109] Same as Example 6, except that unit (c) is replaced with a monomer as shown in Table 1.

[0110] Example 12 Preparation of liquid suspension media

[0111] Same as Example 6, except that unit (c) is replaced with a monomer as shown in Table 1.

[0112] Table 1. Structural formulas of unit (c) for preparing liquid suspension media in Examples 3-12.

[0113]

[0114]

[0115]

[0116] Example 13: Preparation of dimming film and xenon lamp aging test

[0117] The mixture of the initiator that initiates the crosslinking and curing of the polymer matrix precursor, the suspension medium containing solid light-controlling particles 23, and the polymer matrix precursor is mixed evenly, and the resulting mixture is called the light-controlling layer matrix emulsion.

[0118] 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%.

[0119] 0.03 g of photoinitiator 819, 7.0 g of the siloxane copolymer prepared in Example 2, and 3.0 g of the liquid suspension medium containing solid light-controlling particles 23 prepared in Example 3 were mixed evenly to obtain a light-controlling layer matrix emulsion.

[0120] The light-controlling layer matrix emulsion was applied to an ITO / PET transparent conductive film with a thickness of 80 micrometers using a doctor blade type automatic coating machine (MSK-AFA-III, MTI Corporation). 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.

[0121] In this embodiment, a transparent conductive film (transparent electrode) is formed on a plastic sheet substrate.

[0122] The polymer matrix is ​​formed after the polymer matrix precursor is cross-linked and cured.

[0123] In this application, an aging test was conducted using a xenon lamp chamber, and the time required for the color difference ΔE between the dimming film after the aging test and before the test to exceed 5% was recorded. The xenon lamp chamber model was Q-SUN Xe-1 (Q-Lab Corporation), with Daylight-Q filter, black panel temperature of 90°C, and irradiation energy of 75W / m². 2 (300-400nm).

[0124] Under the same test conditions, the longer it takes for the color difference ΔE between the dimming film after the aging test and before the test to be greater than 5%, the better the light resistance stability of the dimming film.

[0125] The specific results are shown in Table 2.

[0126] Example 14: Preparation of dimming film and xenon lamp aging test

[0127] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 4.

[0128] Example 15: Preparation of dimming film and xenon lamp aging test

[0129] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 5.

[0130] Example 16 Preparation of dimming film and xenon lamp aging test

[0131] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 6.

[0132] Example 17 Preparation of dimming film and xenon lamp aging test

[0133] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 7.

[0134] Example 18 Preparation of dimming film and xenon lamp aging test

[0135] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 8.

[0136] Example 19 Preparation of dimming film and xenon lamp aging test

[0137] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 9.

[0138] Example 20 Preparation of dimming film and xenon lamp aging test

[0139] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 10.

[0140] Example 21 Preparation of dimming film and xenon lamp aging test

[0141] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 11.

[0142] Example 22 Preparation of dimming film and xenon lamp aging test

[0143] Same as Example 13, except that the mixture of liquid suspension media prepared in Example 3 is replaced with the mixture of liquid suspension media prepared in Example 12.

[0144] Comparative Example 1 Preparation of (c)-free liquid suspension media

[0145] Same as Example 3, except without unit (c).

[0146] Comparative Example 2 Preparation of (c)-free liquid suspension media

[0147] Same as Example 6, except without unit (c).

[0148] Comparative Example 3 Preparation of dimming film and xenon lamp aging test

[0149] Same as Example 13, except that the mixture of liquid suspension media prepared in Comparative Example 1 is used instead of the mixture of liquid suspension media prepared in Example 3.

[0150] Comparative Example 4 Preparation of dimming film and xenon lamp aging test

[0151] Same as Example 13, except that the mixture of liquid suspension media prepared in Comparative Example 2 is used instead of the mixture of liquid suspension media prepared in Example 3.

[0152] The results of Examples 13-22 and Comparative Examples 3-4 are shown in Table 2 below.

[0153] Table 2. Xenon lamp aging test results of Examples 13-22 and Comparative Examples 3-4

[0154]

[0155]

[0156] As can be seen from the comparison of the xenon lamp aging effects of Examples 13-22 and Comparative Examples 3-4 in Table 2, adding at least one (c) acrylate monomer with a conjugated π-electron system structure has a significant effect on improving the light resistance stability of the dimming film. The time taken for ΔE > 5% is much longer than that of the dimming film prepared with the suspension medium without adding (c) acrylate monomer with a conjugated π-electron system structure. This solution can fully meet the actual application requirements of the dimming film.

[0157] 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 the invention is also fully applicable to light valves with a glass substrate, i.e., dimming glass. The descriptions of the above embodiments are merely to aid in understanding the method and core ideas of the 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 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, comprising: First transparent substrate, The first transparent electrode is formed on the first transparent substrate. Second transparent substrate, The second transparent electrode is formed on the second transparent substrate. The first transparent electrode and the second transparent electrode are arranged opposite to each other, and A light-controlling layer is disposed between the first transparent electrode and the second transparent electrode; the light-controlling layer comprises a polymer matrix; The polymer matrix contains suspended medium droplets, and solid light-controlling particles are distributed within the suspended medium droplets. The suspension medium is obtained from at least one acrylate copolymer, characterized in that the acrylate copolymer is obtained by copolymerization of monomers comprising the following units under the action of a copolymerization catalyst: (a) is selected from alkyl acrylate monomers. (b) hydroxy acrylate monomers, and (c) An acrylate monomer having a conjugated π-electron system structure, having the following structural formula: in, R is H or CH3. X is a group having a conjugated π-electron structure and contains at least one of an ortho-hydroxyphenyl substituent, a nitrogen-containing heterocyclic substituent, or a carbonylbenzene ring substituent.

2. The light valve according to claim 1, characterized in that, The proportions of the monomers forming units (a), (b), and (c) of the acrylate copolymer are as follows: assuming a total mass of 100 parts, the proportion of monomer (a) in unit (a) is 50-95 parts by mass, the proportion of monomer (b) in unit (b) is 2-30 parts by mass, and the proportion of monomer (c) in unit (c) is 3-20 parts by mass.

3. The light valve according to claim 1, characterized in that, The peak molecular weight of the acrylate copolymer is 2000-7000.

4. The light valve according to claim 1, characterized in that, The copolymerization catalyst is a thermally initiated free radical catalyst, selected from at least one of azo initiator, hydrogenated tributyltin (n-Bu3SnH) / AIBN, and ammonium persulfate.

5. The light valve according to claim 1, characterized in that, The suspension medium also includes a non-conductive liquid; The non-conductive liquid is selected from at least one of fluorocarbon organic compounds, phthalates, triterpenes, dodecylbenzene, polybutene oil, epoxidized soybean oil, and epoxidized linseed oil.

6. The light valve according to claim 1, characterized in that, The solid light-controlling particles are selected from one or more of oxide nanorods, perovskite nanorods, and polyiodine compound nanorods; the particle length of the solid light-controlling particles is 50-800 nm; and the particle aspect ratio of the solid light-controlling particles is 2-30.

7. The light valve according to claim 1, characterized in that, The polymer matrix is ​​formed by cross-linking and curing an organosilicon oil polymer matrix precursor with unsaturated bonds.

8. The light valve according to claim 1, characterized in that, The first transparent substrate and the second transparent substrate are glass plates.

9. The light valve according to claim 1, characterized in that, The first and second transparent substrates are transparent plastic sheets.

10. The light valve according to claim 1, characterized in that, The first transparent electrode and the second transparent electrode are each independently selected from ITO conductive layer, FZO conductive layer, IZO conductive layer, GZO conductive layer, AZO conductive layer, PEDOT conductive layer, nano Ag wire conductive layer, conductive graphene and nano Cu wire conductive layer.

11. The light valve according to claim 1, characterized in that, The first transparent electrode and / or the second transparent electrode are covered with an adhesive layer, the adhesive layer material including at least one of epoxy resin, polyurethane, polyimide resin, polystyrene resin, acrylic resin, modified acrylic and silicone resin.

12. A method for preparing the light valve device according to claim 1, characterized in that, include Provides solid-state light-controlling particles; Provide a suspension medium; The solid light-controlling particles are mixed with the suspension medium to form a mixture containing the solid light-controlling particles in the suspension medium; Provide polymer matrix precursors; The initiator that initiates the crosslinking and curing of the polymer matrix precursor, the mixture of the suspension medium containing solid light-controlling particles, and the polymer matrix precursor are mixed to obtain a light-controlling layer matrix emulsion. The above-mentioned light-controlling layer matrix emulsion is coated onto the first transparent electrode of the first transparent substrate to form a light-controlling layer wet film; The second transparent electrode on the second transparent substrate is covered on the wet film of the light control layer; and The light control layer wet film is cross-linked and cured to obtain the light valve device.

13. A dimming glass assembly with anti-light stability, characterized in that, Include First glass plate and second glass plate, and A light valve as described in any one of claims 1 to 11 is disposed between the first glass plate and the second glass plate.

14. The dimming glass assembly with anti-light stability according to claim 13, characterized in that, A first interlayer is provided between the first glass plate and the light valve, and / or a second interlayer is provided between the second glass plate and the light valve.

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