Microcapsule polymerization coated dye liquid crystal nano light valve and preparation method thereof

Abstract

The invention relates to a microcapsule polymerization coated dye liquid crystal nano light valve and a preparation method thereof, and relates to the technical field of liquid crystal display. The microcapsule dye liquid crystal slurry comprises the following components in parts by mass: 40-60 parts of dye liquid crystal microcapsules and 40-60 parts of polymer dispersed slurry. The preparation method comprises the following steps: adding dye liquid crystal microcapsules into polymer dispersion slurry, carrying out ultrasonic dispersion to obtain microcapsule dye liquid crystal slurry, coating the surfaces of two indium tin oxide conductive films with the microcapsule dye liquid crystal slurry, and attaching the two surfaces coated with the microcapsule dye liquid crystal slurry to obtain the conductive film. And carrying out curing treatment under ultraviolet irradiation to obtain the microcapsule polymerization coated dye liquid crystal nano light valve. The nano light valve has the effect of improving the contrast ratio and the resolution ratio of the nano light valve, and the black matrix phenomenon can be effectively reduced.

Description

Technical Field

[0001] The present application relates to the field of liquid crystal display technology, and in particular to a microcapsule polymerized dye-encapsulated liquid crystal nano light valve and a preparation method thereof. Background Art

[0002] At present, liquid crystal display technology is widely used in the fields of television, computer monitors, etc., among which liquid crystal light valves, as one of the core components, form images by changing the transmittance of light. Traditional liquid crystal light valves mainly rely on electric field effect regulation, but have certain limitations in response speed, energy consumption and stability. In recent years, dye-sensitized liquid crystal light valves have attracted widespread attention due to their unique optical properties.

[0003] Dye-sensitized liquid crystal light valves usually mix dye-sensitized liquid crystals with glue directly. Since the glue has some holes, the dye liquid crystals will accumulate in the holes, and some dye liquid crystals will overflow on the surface. The dye liquid crystals are not completely accumulated in the holes, and the dye liquid crystals in the holes can rotate, while the dye liquid crystals on the surface are prone to black background after solidification, which makes it impossible to effectively improve the contrast, thereby affecting the resolution of the light valve, so it needs to be improved. Summary of the invention

[0004] In order to improve the contrast of a light valve, the present application provides a microcapsule polymer-encapsulated dye liquid crystal nano light valve and a preparation method thereof.

[0005] The present application provides a microcapsule polymer-encapsulated dye liquid crystal nano light valve and a preparation method thereof using the following technical solutions: In the first aspect, the present application provides a microcapsule polymer-encapsulated dye liquid crystal nano light valve, which adopts the following technical solution: a microcapsule polymer-encapsulated dye liquid crystal nano light valve, the preparation raw materials include microcapsule dye liquid crystal paste and indium tin oxide conductive film, and the microcapsule dye liquid crystal paste includes the following components in mass fractions: Dye liquid crystal microcapsules 40-60 parts 40-60 parts of polymer dispersion slurry.

[0006] The nano light valve with dye-encapsulated polymerized microcapsules has good light transmittance and high contrast. By embedding dye liquid crystal in microcapsules, the liquid crystal molecules can be effectively protected, and at the same time, the liquid crystal molecules can be evenly dispersed in the slurry, and then evenly dispersed in the two layers of indium tin oxide conductive film, and can rotate freely under the action of the electric field, successfully realizing the switching between the bright state and the dark state, and improving the contrast of the nano light valve; this can avoid the overflow of dye liquid crystal on the surface, and after curing, it is fixed on the surface and cannot rotate, reducing the occurrence of black bottom phenomenon, thereby improving the resolution and contrast of the light valve.

[0007] Preferably, the dye liquid crystal microcapsule comprises dye-sensitized liquid crystal and polymer microcapsule wall material.

[0008] Dye-sensitized liquid crystal has photosensitivity and optical anisotropy, and can respond sensitively to light; dye-sensitized liquid crystal has good light absorption ability, and can use dye molecules to efficiently capture light energy, thereby realizing the conversion of light signals into electrical signals or other forms of energy; liquid crystal can rotate under external stimuli such as electric fields, realizing the conversion between bright and dark states, thereby improving the contrast of the nano light valve; wrapping the dye-sensitized liquid crystal with polymer microcapsule wall materials can reduce the overflow of liquid crystal molecules and thus prevent the liquid crystal molecules from being fixed and the black bottom phenomenon from occurring, allowing the liquid crystal molecules to rotate freely under the action of the electric field, thereby improving the contrast of the nano light valve.

[0009] Preferably, the raw material for preparing the polymer microcapsule wall material includes one of polypropylene, epoxy resin and polymethyl methacrylate.

[0010] Polypropylene, epoxy resin and polymethyl methacrylate are three polymers that can form uniform and dense microcapsule walls, which can effectively encapsulate dye-sensitized liquid crystals. At the same time, these three wall materials have good stability, weather resistance and compatibility, which can reduce the impact of environmental factors on dye-sensitized liquid crystals, allowing the microcapsules to be evenly dispersed in the slurry and improving the long-term stability of the nano light valve.

[0011] Preferably, the dye liquid crystal microcapsules are prepared by the following steps: The dye-sensitized liquid crystal and the polymer microcapsule wall material are mixed, an organic solvent is added, and an oil phase is obtained after ultrasonic treatment; a polyvinyl alcohol aqueous solution is used as the water phase, and the oil phase is slowly dropped into the water phase under stirring in a water bath, and emulsification is maintained after the dropwise addition is completed to obtain a mixed solution; the polyvinyl alcohol aqueous solution is added to the mixed solution under stirring conditions, and the temperature is raised and stirred to react to obtain a product solution; the product solution is filtered to obtain microcapsules, and the obtained microcapsules are washed and dried to obtain dye liquid crystal microcapsules.

[0012] The dye liquid crystal microcapsules prepared according to the above steps have good stability, and the dye-sensitized liquid crystals can rotate freely in the polymer microcapsule wall material to improve the contrast of the light valve.

[0013] Preferably, the washing step comprises: dispersing the microcapsules in water, filtering after ultrasonication, and washing with an organic solvent by filtering for 2-4 times to obtain washed microcapsules.

[0014] By washing through the above steps, the dye-sensitized liquid crystal molecules that are not successfully encapsulated can be effectively removed without destroying the microcapsule structure, reducing the phenomenon that the unencapsulated liquid crystal molecules are fixed and unable to rotate, thereby reducing the black bottom phenomenon and improving the contrast of the nano light valve.

[0015] Preferably, the dye-sensitized liquid crystal comprises an ester-modified anthraquinone dye, an azo dye and a liquid crystal, and the raw materials for preparing the ester-modified anthraquinone dye comprise anthraquinone dye and an esterification modifier.

[0016] Ester-modified anthraquinone dyes and azo dyes can work synergistically to sensitize liquid crystal molecules, display a wide color gamut and high color saturation, enhance the photosensitivity and photostability of dye-sensitized liquid crystals, and make the liquid crystals more responsive under the action of an electric field, thereby enhancing the contrast of the nano light valve.

[0017] Preferably, the esterification modifier includes one of p-octylphenol, p-heptylphenol and p-pentylphenol.

[0018] As esterification modifiers for anthraquinone dyes, 4-octylphenol, 4-heptylphenol and 4-pentylphenol can enhance the solubility of the dyes in liquid crystals, facilitate their arrangement in liquid crystals, and increase the order parameters in the liquid crystal molecules, thereby better improving the response sensitivity of the liquid crystals, enhancing the vividness of the colors, and improving the contrast of the nano light valve.

[0019] Preferably, the raw materials for preparing the polymer dispersion slurry include acrylate monomers, fluorine-containing acrylates, sulfur-containing acrylates, film-forming resins and initiators.

[0020] The polymer slurry prepared by acrylate monomers, fluorine-containing acrylates, sulfur-containing acrylates, film-forming resins and initiators has good dispersibility and compatibility, which can make the dye liquid crystal microcapsules evenly dispersed in the slurry, thereby improving the contrast of the nano light valve; the fluorine element in the fluorine-containing acrylate has a low polarizability, which can reduce the refractive index, reduce the refraction and scattering of light, enhance the light transmittance of the nano light valve, and improve the contrast; at the same time, the fluorine element can improve the ultraviolet resistance of the nano light valve, improve the weather resistance of the nano light valve, and extend its service life; sulfur-containing acrylates can introduce sulfur groups into the system, which can improve the optical stability of the nano light valve, adjust the optical band gap, and enable the nano light valve to respond more sensitively to change the light transmittance and improve its contrast.

[0021] Preferably, the film-forming resin includes one of acrylic film-forming resin, polyurethane film-forming resin and epoxy film-forming resin.

[0022] Acrylic film-forming resin, polyurethane film-forming resin and epoxy film-forming resin can promote the dispersion of slurry and form a uniform film in the indium tin oxide conductive film, so that the microcapsules are evenly dispersed and the contrast of the nano light valve is improved.

[0023] In a second aspect, the present application provides a method for preparing a microcapsule polymer-encapsulated dye liquid crystal nano light valve, using the following technical solution: A method for preparing a microcapsule polymerized dye-encapsulated liquid crystal nano light valve comprises the following steps: Dye liquid crystal microcapsules are added to polymer dispersion slurry, and after ultrasonic dispersion, microcapsule dye liquid crystal slurry is obtained. The microcapsule dye liquid crystal slurry is coated on the surfaces of two indium tin oxide conductive films, and the two surfaces coated with the microcapsule dye liquid crystal slurry are laminated. After curing treatment under ultraviolet light, a microcapsule polymer-encapsulated dye liquid crystal nano light valve is obtained.

[0024] The nano light valve prepared according to the above steps has high contrast and can maintain good working performance for a long time.

[0025] In summary, the present application includes at least one of the following beneficial technical effects: 1. Microcapsule polymerized dye-encapsulated liquid crystal nano light valve has good light transmittance and high contrast. By embedding dye liquid crystal in microcapsules, the liquid crystal molecules can be effectively protected, and at the same time, the liquid crystal molecules can be evenly dispersed in the slurry, and then evenly dispersed in the two layers of indium tin oxide conductive film, and can rotate freely under the action of the electric field, successfully realizing the switching between the bright state and the dark state, and improving the contrast of the nano light valve; this can avoid the overflow of dye liquid crystal on the surface, and after curing, it is fixed on the surface and cannot rotate, reducing the occurrence of black bottom phenomenon, thereby improving the resolution and contrast of the light valve.

[0026] 2. Dye-sensitized liquid crystal has photosensitivity and optical anisotropy, and can respond sensitively to light; dye-sensitized liquid crystal has good light absorption ability, and can use dye molecules to efficiently capture light energy, thereby realizing the conversion of light signals to electrical signals or other forms of energy; liquid crystal can rotate under external stimuli such as electric fields, realizing the conversion between bright and dark states, thereby improving the contrast of the nano light valve; wrapping the dye-sensitized liquid crystal with polymer microcapsule wall materials can reduce the overflow of liquid crystal molecules and thus prevent the liquid crystal molecules from being fixed and the black bottom phenomenon from occurring, so that the liquid crystal molecules can rotate freely under the action of the electric field, thereby improving the contrast of the nano light valve.

[0027] 3. The polymer slurry prepared by acrylate monomers, fluorine-containing acrylates, sulfur-containing acrylates, film-forming resins and initiators has good dispersibility and compatibility, which can make the dye liquid crystal microcapsules evenly dispersed in the slurry, thereby improving the contrast of the nano light valve; the fluorine element in the fluorine-containing acrylate has a low polarizability, which can reduce the refractive index, reduce the refraction and scattering of light, enhance the light transmittance of the nano light valve, and improve the contrast; at the same time, the fluorine element can improve the ultraviolet resistance of the nano light valve, improve the weather resistance of the nano light valve, and extend its service life; sulfur-containing acrylates can introduce sulfur groups into the system, which can improve the optical stability of the nano light valve, adjust the optical band gap, and enable the nano light valve to respond more sensitively to change the light transmittance and improve its contrast. DETAILED DESCRIPTION

[0028] The present application discloses a microcapsule polymer-encapsulated dye liquid crystal nano light valve and a preparation method thereof. The raw materials used in the present application can be obtained from commercially available raw materials unless otherwise specified. The present application is further described in detail in conjunction with the embodiments below: Raw material description: anthraquinone dyes are 4-nitro-1-aminoanthraquinone-2-carboxylic acid (CAS No.: 2058-02-8), p-octylphenol (CAS No.: 1806-26-4), p-heptylphenol (CAS No.: 1987 -50-4), p-amylphenol (CAS No.: 14938-35-3), 4-dimethylaminopyridine (CAS No.: 1122-58-3), dicyclohexylcarbodiimide (CAS No.: 538-75-0), liquid crystal is nematic liquid crystal BJD010200-100 (TNI=361.0K, Δn=0.217, Δε=11.7), azo dye is disazo blue dye, model G168, polypropylene model is PP TM100NP was purchased from Dongguan Baishun New Materials Co., Ltd., polyvinyl alcohol (CAS No.: 9002-89-5), the acrylate monomer was hydroxyethyl methacrylate (CAS No.: 868-77-9), the fluorinated acrylate was ethyl acrylate (N-methylperfluorohexylsulfonamido) (CAS No.: 67584-57-0), the sulfur-containing acrylate was ethyl 2-(methylthio)methacrylate (CAS No.: 14216-23-0), and the initiator was 2,2-diethyl Oxyacetophenone (CAS No.: 6175-45-7) and polyurethane film-forming resin were purchased from Guangzhou Ruilin New Materials Co., Ltd., epoxy resin model 5301AB-80 was purchased from Dongguan Lishun Composite Materials Co., Ltd., epoxy film-forming resin model 1008AB-5 was purchased from Dongguan Lishun Composite Materials Co., Ltd., polymethyl methacrylate model was Evonik Degussa 8817, and acrylic film-forming resin model S-611 was purchased from Qingdao Wanjia Huixin Surface Materials Technology Co., Ltd.

[0029] Preparation Example 1 5.62 g of 4-nitro-1-aminoanthraquinone-2-carboxylic acid and 3.45 g of p-pentylphenol were dispersed in 250 mL of dichloromethane, 0.29 g of 4-dimethylaminopyridine was added, and the mixture was stirred at 200 rpm for 30 min under nitrogen protection to obtain a mixed solution; 4.95 g of dicyclohexylcarbodiimide was dissolved in 50 mL of dichloromethane to obtain a dicyclohexylcarbodiimide solution, and the dicyclohexylcarbodiimide solution was added to the mixed solution within 4 h. After the reaction was continued for 12 h, water was added to the reacted solution and the solution was allowed to stand. After suction filtration, the filtrate was separated, and the organic phase was rotary evaporated to obtain a crude product. The crude product was recrystallized in a solvent with a volume ratio of ethyl acetate and dichloromethane of 1:1, and a preliminary product was obtained after chromatography.

[0030] The preliminary product prepared above and 200 mL of ethyl acetate were mixed into a reactor, 0.1 g of palladium carbon was added to the reactor, the air in the reactor was replaced with nitrogen and hydrogen three times each, the temperature was raised to 45°C after the replacement was completed, hydrogen was passed until the pressure was 2 MPa, and the reaction was kept warm for 12 hours, then the ventilation was stopped, the hydrogen was replaced with nitrogen three times, the reaction was filtered, and the filtrate was spin-dried to obtain a crude product, the crude product was recrystallized in a solvent with a volume ratio of ethyl acetate and dichloromethane of 1:1, and the ester-modified anthraquinone dye I was obtained after chromatography.

[0031] Preparation Example 2 Preparation Example 2 is based on Preparation Example 1. In Preparation Example 2, 3.45 g of p-amylphenol is replaced with 4.04 g of p-heptylphenol to obtain ester-modified anthraquinone dye II.

[0032] Preparation Example 3 Preparation Example 3 is based on Preparation Example 1. In Preparation Example 3, 3.45 g of p-amylphenol is replaced with 4.33 g of p-octylphenol to obtain ester-modified anthraquinone dye III.

[0033] Example 1 Preparation of dye liquid crystal microcapsules 0.75g of azo dye, 0.75g of ester-modified anthraquinone dye I prepared in Preparation Example 1, 48.5g of liquid crystal and 5g of polypropylene were added to 500mL of toluene, and after ultrasonication for 1h, an oil phase was obtained; 2L of polyvinyl alcohol aqueous solution with a mass content of 2% was used as the water phase, and the oil phase was slowly added to the water phase in a 20°C water bath and stirred at a speed of 1500rpm, and the addition was completed within 2h. After the addition was completed, the emulsification was maintained for 30min to obtain a mixed solution; the mixed solution was stirred at a speed of 300rpm, and 2L of polyvinyl alcohol aqueous solution with a mass content of 2% was added to the mixed solution, and the temperature was raised to 35°C within 30min, and the reaction was continued at a speed of 300rpm for 8h to obtain a product solution. The product solution was filtered to obtain microcapsules, and the obtained microcapsules were dispersed in water, ultrasonicated for 5min, and washed twice with dichloromethane to obtain washed microcapsules, and the washed microcapsules were dried in an oven at 40°C to obtain dye liquid crystal microcapsules.

[0034] Preparation of microcapsule polymer-encapsulated dye-encapsulated liquid crystal nano-light valve 60 g of acrylate monomer, 15 g of fluorine-containing acrylate and 25 g of sulfur-containing acrylate were mixed, stirred at 500 rpm for 30 min, 0.5 g of initiator and 30 g of polyurethane resin were added, and stirring was continued at 500 rpm for 30 min to obtain a polymer dispersion slurry.

[0035] 40g of dye liquid crystal microcapsules were added to 60g of polymer dispersion slurry, and microcapsule dye liquid crystal slurry was obtained after ultrasonic dispersion. The microcapsule dye liquid crystal slurry was coated on the surfaces of two indium tin oxide conductive films, and the two surfaces coated with the microcapsule dye liquid crystal slurry were laminated. After curing treatment under ultraviolet light, a microcapsule polymer-encapsulated dye liquid crystal nano light valve was obtained.

[0036] Example 2 Preparation of dye liquid crystal microcapsules 0.75g of azo dye, 0.75g of ester-modified anthraquinone dye II prepared in Preparation Example 2, 48.5g of liquid crystal and 5g of epoxy resin were mixed, 250mL of dichloromethane and 250mL of acetone were added in sequence, and the mixture was ultrasonicated for 1h to obtain an oil phase; 2L of 2% polyvinyl alcohol aqueous solution was used as the water phase, and the oil phase was slowly added dropwise to the water phase in a 20°C water bath and stirred at 1500rpm, and the addition was completed within 2h. After the addition was completed, the emulsification was maintained for 30min to obtain a mixed solution; the mixed solution was stirred at a speed of 300rpm, 2L of 2% polyvinyl alcohol aqueous solution was added to the mixed solution, the temperature was raised to 35°C within 30min, and the reaction was continued at a speed of 300rpm for 8h to obtain a product solution. The product solution was filtered to obtain microcapsules, and the obtained microcapsules were dispersed in water. After ultrasonic treatment for 5 minutes, the microcapsules were washed four times by suction filtration with dichloromethane to obtain washed microcapsules. The washed microcapsules were dried in an oven at 40° C. to obtain dye liquid crystal microcapsules.

[0037] Preparation of microcapsule polymer-encapsulated dye-encapsulated liquid crystal nano-light valve 60 g of acrylate monomer, 15 g of fluorine-containing acrylate and 25 g of sulfur-containing acrylate were mixed, stirred at 500 rpm for 30 min, 0.5 g of initiator and 30 g of epoxy film-forming resin were added, and stirring was continued at 500 rpm for 30 min to obtain a polymer dispersion slurry.

[0038] 60g of dye liquid crystal microcapsules were added to 40g of polymer dispersion slurry, and microcapsule dye liquid crystal slurry was obtained after ultrasonic dispersion. The microcapsule dye liquid crystal slurry was coated on the surfaces of two indium tin oxide conductive films, and the two surfaces coated with the microcapsule dye liquid crystal slurry were laminated. After curing treatment under ultraviolet light, a microcapsule polymer-encapsulated dye liquid crystal nano light valve was obtained.

[0039] Example 3 Preparation of dye liquid crystal microcapsules 0.75g of azo dye, 0.75g of ester-modified anthraquinone dye III prepared in Preparation Example 3, 48.5g of liquid crystal and 5g of polymethyl methacrylate were mixed, 450mL of dichloromethane and 50mL of acetone were added in sequence, and the mixture was ultrasonicated for 1h to obtain an oil phase; 2L of 2% polyvinyl alcohol aqueous solution was used as the water phase, and the oil phase was slowly added dropwise to the water phase in a 20°C water bath and stirred at 1500rpm, and the addition was completed within 2h. After the addition was completed, the emulsification was maintained for 30min to obtain a mixed solution; the mixed solution was stirred at a speed of 300rpm, 2L of 2% polyvinyl alcohol aqueous solution was added to the mixed solution, the temperature was raised to 35°C within 30min, and the reaction was continued at a speed of 300rpm for 8h to obtain a product solution. The product solution was filtered to obtain microcapsules, and the obtained microcapsules were dispersed in water. After ultrasonic treatment for 5 minutes, the microcapsules were washed three times with dichloromethane by suction filtration to obtain washed microcapsules. The washed microcapsules were dried in an oven at 40° C. to obtain dye liquid crystal microcapsules.

[0040] Preparation of microcapsule polymer-encapsulated dye-encapsulated liquid crystal nano-light valve 60 g of acrylate monomer, 15 g of fluorine-containing acrylate and 25 g of sulfur-containing acrylate were mixed, stirred at 500 rpm for 30 min, 0.5 g of initiator and 30 g of acrylic film-forming resin were added, and stirring was continued at 500 rpm for 30 min to obtain a polymer dispersion slurry.

[0041] 50g of dye liquid crystal microcapsules were added to 50g of polymer dispersion slurry, and microcapsule dye liquid crystal slurry was obtained after ultrasonic dispersion. The microcapsule dye liquid crystal slurry was coated on the surfaces of two indium tin oxide conductive films, and the two surfaces coated with the microcapsule dye liquid crystal slurry were laminated. After curing treatment under ultraviolet light, a microcapsule polymer-encapsulated dye liquid crystal nano light valve was obtained.

[0042] Example 4 Example 4 is based on Example 3. The only difference between Example 4 and Example 3 is that in Example 4, the oil phase is slowly added dropwise to the water phase under stirring at a speed of 1000 rpm.

[0043] Example 5 Example 5 is based on Example 3. The only difference between Example 5 and Example 3 is that in Example 5, no washing step is performed when preparing the dye liquid crystal microcapsules.

[0044] Example 6 Example 6 is based on Example 3. The only difference between Example 6 and Example 3 is that in Example 6, the ester-modified anthraquinone dye is replaced by anthraquinone dye.

[0045] Example 7 Example 7 is based on Example 3. The only difference between Example 7 and Example 3 is that in Example 7, the fluorinated acrylate is replaced by an equal amount of acrylate monomer when preparing the polymer dispersion slurry.

[0046] Example 8 Example 8 is based on Example 3. The only difference between Example 8 and Example 3 is that in Example 8, when preparing the polymer dispersion slurry, the fluorine-containing acrylate and the sulfur-containing acrylate are replaced by an equal amount of acrylate monomers.

[0047] Comparative Example 1 Comparative Example 1 is based on Example 3. The only difference between Comparative Example 1 and Example 3 is that in Comparative Example 1, the dye liquid crystal microcapsules are replaced with dye-sensitized liquid crystals.

[0048] Performance testing According to GB / T25273-2010 Determination of haze of thin films for liquid crystal displays (LCD) - Integrating sphere method, the haze and transmittance of the sample were tested using a transmittance haze meter. The transmittance and haze were calculated and recorded after 48V power-on and power-off for 60s. The contrast ratio was calculated. Contrast ratio = transmittance (亮态) / Transmittance (暗态) Each sample was tested three times, and the average value was taken after measurement. The results are recorded in Table 1.

[0049] Table 1 Test results of transmittance, haze and contrast of nano light valve It can be seen from Table 1 that the light transmittance of Examples 1-3 in the bright state is greater than 58%, the haze is less than 2.2%, the light transmittance in the dark state is less than 1.6%, the haze is greater than 94%, and the contrast is greater than 36.25%, which shows that the nano light valve prepared in this application has a good display effect.

[0050] As can be seen from Table 1, the only difference between Example 4 and Example 3 is that in Example 4, the oil phase is slowly added dropwise to the water phase under stirring at a speed of 1000 rpm. Compared with Example 3, the contrast ratio of Example 4 is reduced. This is because the stirring speed during emulsification into microcapsules is adjusted, which affects the number of liquid crystal molecules embedded in the microcapsules. The reduction in stirring speed reduces the dispersion, and multiple liquid crystal molecules are embedded in the same capsule wall, which in turn affects their free rotation under the action of the electric field, thereby causing a decrease in contrast ratio.

[0051] It can be seen from Table 1 that the only difference between Example 5 and Example 3 is that in Example 5, no washing step is performed when preparing the dye liquid crystal microcapsules. Compared with Example 3, the contrast of Example 5 is reduced. This is because the dye liquid crystal microcapsules are not washed, and some liquid crystal molecules are not successfully embedded and remain on the surface of the microcapsules. After being dispersed into the slurry, they may be fixed after curing and cannot rotate freely, which causes the black bottom phenomenon to appear, reducing the contrast of the light valve.

[0052] It can be seen from Table 1 that the only difference between Example 6 and Example 3 is that in Example 6, the ester-modified anthraquinone dye is replaced by anthraquinone dye, and the contrast ratio of Example 6 is reduced compared with Example 3; this is because the ester-modified anthraquinone dye is replaced by anthraquinone dye, lacking the introduction of long-chain ester groups, and its solubility in liquid crystal molecules is reduced, and the synergistic effect with azo dye molecules is weakened, resulting in a decrease in contrast ratio.

[0053] It can be seen from Table 1 that the only difference between Examples 7 and 8 and Example 3 is that in Example 7, the fluorine-containing acrylate is replaced by an equal amount of acrylate monomer when preparing the polymer dispersion slurry, and in Example 8, the fluorine-containing acrylate and sulfur-containing acrylate are replaced by an equal amount of acrylate monomer when preparing the polymer dispersion slurry. Compared with Example 3, the contrast of Examples 7 and 8 is reduced; this is because the fluorine element and sulfur group in the slurry are reduced, and the lack of the introduction of these two reduces the transmittance of the polymer component in the nano light valve, which in turn affects the transmittance and haze of the nano light valve, thereby reducing the contrast.

[0054] It can be seen from Table 1 that the only difference between Comparative Example 1 and Example 3 is that in Comparative Example 1, the dye liquid crystal microcapsules are replaced with dye-sensitized liquid crystals. Compared with Example 3, the contrast ratio of Comparative Example 1 is reduced. This is because the dye-sensitized liquid crystals lack the encapsulation of the polymer microcapsules and will accumulate or even overflow in the polymer pores, resulting in reduced dispersion. Some liquid crystal molecules are fixed and cannot rotate, thereby causing a black bottom phenomenon, which greatly reduces the contrast ratio of the nano light valve.

[0055] This specific embodiment is only an explanation of the present application, and it is not a limitation of the present application. Through the above description, relevant staff can make various changes and modifications without deviating from the technical idea of ​​the present application. The technical scope of the present application is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A microcapsule polymer-encapsulated dye liquid crystal nano light valve, characterized in that: The preparation raw materials include microcapsule dye liquid crystal paste and indium tin oxide conductive film, and the microcapsule dye liquid crystal paste includes the following components in parts by weight: Dye liquid crystal microcapsules 40-60 parts 40-60 parts of polymer dispersion slurry.

2. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 1, characterized in that: The dye liquid crystal microcapsule comprises dye-sensitized liquid crystal and polymer microcapsule wall material.

3. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 2, characterized in that: The raw material for preparing the polymer microcapsule wall material includes one of polypropylene, epoxy resin and polymethyl methacrylate.

4. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 3, characterized in that: The dye liquid crystal microcapsules are prepared by the following steps: The dye-sensitized liquid crystal and the polymer microcapsule wall material are mixed, an organic solvent is added, and an oil phase is obtained after ultrasonic treatment; a polyvinyl alcohol aqueous solution is used as the water phase, and the oil phase is slowly added dropwise to the water phase under stirring in a water bath, and emulsification is maintained after the addition is completed to obtain a mixed solution; the polyvinyl alcohol aqueous solution is added to the mixed solution under stirring, and the mixture is heated and stirred to react to obtain a product solution; The product solution is filtered to obtain microcapsules, and the obtained microcapsules are washed and dried to obtain dye liquid crystal microcapsules.

5. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 4, characterized in that: The washing step comprises: dispersing the microcapsules in water, filtering after ultrasonication, and washing with an organic solvent by filtering for 2-4 times to obtain washed microcapsules.

6. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 2, characterized in that: The dye-sensitized liquid crystal comprises an ester-modified anthraquinone dye, an azo dye and a liquid crystal, and the raw materials for preparing the ester-modified anthraquinone dye comprise an anthraquinone dye body and an esterification modifier.

7. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 6, characterized in that: The esterification modifier includes one of p-octylphenol, p-heptylphenol and p-pentylphenol.

8. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 1, characterized in that: The raw materials for preparing the polymer dispersion slurry include acrylate monomers, fluorine-containing acrylate, sulfur-containing acrylate, film-forming resin and initiator.

9. The microcapsule polymer-encapsulated dye liquid crystal nano light valve according to claim 8, characterized in that: The film-forming resin includes one of an acrylic film-forming resin, a polyurethane film-forming resin and an epoxy film-forming resin.

10. A method for preparing a microcapsule polymer-encapsulated dye liquid crystal nano light valve as claimed in any one of claims 1 to 9, characterized in that: The steps include: Dye liquid crystal microcapsules are added to polymer dispersion slurry, and after ultrasonic dispersion, microcapsule dye liquid crystal slurry is obtained. The microcapsule dye liquid crystal slurry is coated on the surfaces of two indium tin oxide conductive films, and the two surfaces coated with the microcapsule dye liquid crystal slurry are laminated. After curing treatment under ultraviolet light, a microcapsule polymer-encapsulated dye liquid crystal nano light valve is obtained.

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