Mini LED Backlight Module for Healthy Eye Protection and Its Manufacturing Method

Abstract

The present invention relates to the technical field of backlight modules, and specifically relates to a Mini LED backlight module for healthy eye protection and a manufacturing method thereof. The present application discloses a Mini LED backlight module for healthy eye protection, which includes a Mini LED light board and a diffusion board arranged above the Mini LED light board. The diffusion board includes a base material and coatings coated on both sides of the base material; the base material is a PET film; the coating is a coating containing modified hollow mesoporous silica. The Mini LED backlight module for healthy eye protection described in the present application can obtain a backlight module with obvious diffusion effect and good light uniformity by preparing a backlight board with high light transmittance, high haze and good light diffusion property, and this backlight module has a good healthy eye protection effect.

Description

Technical Field

[0001] The present invention relates to the technical field of backlight modules. More specifically, the present invention relates to a Mini LED backlight module for healthy eye protection and a manufacturing method thereof. Background Art

[0002] Liquid crystal display has become the mainstream flat panel display technology. Since liquid crystals do not emit light, a backlight is required to provide illumination light. The brightness, chromaticity, and volume of the backlight module largely determine the performance of the final display. The thinness of display products has become a popular trend, which requires the backlight module to minimize its thickness to the greatest extent.

[0003] Light Emitting Diode (LED) has already been the mainstream light source for liquid crystal display backlight modules. A direct - type backlight module usually includes multiple LEDs. As the size of the LED chip increases, the power of a single LED continuously increases, and the distance between LEDs becomes larger and larger. Usually, it is necessary to first diffuse the light emitted by the LEDs through a secondary lens, and then further scatter the light through a diffusion film to form a uniform extended light source. The optical distance (OD) between the LED and the diffusion film is usually relatively large, resulting in a relatively large thickness of the backlight module. With the development of semiconductor technology, the size of the LED light - emitting chip has been reduced to a few hundred micrometers, and Mini LED chips have emerged. Mini LED chips are small in size and low in heat generation, and can be densely arranged in a matrix in the backlight module. With the continuous development of display technology, consumers' requirements for the visual effect and health performance of displays are increasing day by day. The existing Mini LED backlight modules still need to be improved in terms of light uniformity and eye - protection effect.

[0004] In a Mini LED backlight module, due to the small size and high - density arrangement of Mini LED chips, theoretically, a more uniform light distribution can be generated. However, when the diffusion film is too close to the chip, its diffusion effect weakens, which may lead to too high local light intensity, forming "light spots" or "hot spots". This non - uniform light distribution will directly affect the visual comfort of users. Prolonged viewing may cause eye fatigue; moreover, the non - uniform light distribution not only affects the viewing experience, but also may cause additional stress on the eyes. The eyes need to continuously adjust the focal length and pupil size to adapt to the changes in light, which will increase the burden on the visual system. In the long run, it may lead to vision loss or other eye problems.

[0005] Therefore, it is necessary to provide a Mini LED backlight module for healthy eye protection and a manufacturing method thereof. Summary of the Invention

[0006] To overcome the deficiencies of the prior art, the present invention provides a Mini LED backlight module for healthy eye protection and a manufacturing method thereof. By preparing a backlight plate with high light transmittance, high haze, and good light diffusion properties, a backlight module with obvious diffusion effect and good light uniformity can be obtained, and this backlight module has a good effect on healthy eye protection.

[0007] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0008] The first object of this application is to provide a Mini LED backlight module for healthy eye protection, which includes a Mini LED light board and a diffusion plate arranged above the Mini LED light board. The diffusion plate includes a substrate and coatings applied on both sides of the substrate; the substrate is a PET film; the coatings are coatings containing modified hollow mesoporous silica.

[0009] In some embodiments, the pore diameter of the modified hollow mesoporous silica is 1 - 15 nm; the thickness of the PET film is 50 - 80 μm; the thickness of the coatings is 10 - 15 μm.

[0010] In some embodiments, the coating solution for forming the coatings includes the following raw materials in parts by weight:

[0011] 20 - 30 parts of a light diffusing agent, 10 - 20 parts of modified hollow mesoporous silica, 0.5 - 0.8 parts of a photoinitiator, 20 - 30 parts of a diluent, 10 - 20 parts of polyurethane acrylate, and 5 - 8 parts of a grafting agent.

[0012] In some embodiments, the photoinitiator is any one of 2 - hydroxy - 2 - methyl - 1 - phenyl - 1 - propanone and 4 - methylstyryldiphenyl iodonium salt.

[0013] In some embodiments, the diluent is dipropylene glycol diacrylate.

[0014] In some embodiments, the grafting agent is any one of 2 - hydroxyethyl methacrylate and glycidyl methacrylate.

[0015] In some embodiments, the manufacturing method of the modified hollow mesoporous silica includes the following steps:

[0016] Take 1 g of nano - silica, add it to 90 mL of water for dispersion, then add 20 ml of an ethanol solution of cetyltrimethylammonium bromide with a concentration of 10 - 15 mg / ml. After stirring at room temperature for 2 - 3 h, add 5 - 6 g of anhydrous sodium carbonate, stir at 35°C for 12 h, then raise the temperature to 50°C and stir for another 24 h. After the reaction ends, carry out post - treatment to obtain hollow mesoporous nano - silica;

[0017] Take 0.5 g of hollow mesoporous nano-silica and 1 g of a coupling agent, mix them thoroughly, and stir them at room temperature for 24-36 hours to obtain modified hollow mesoporous silica.

[0018] In some embodiments, the coupling agent is any one of γ-methacryloxypropyltrimethoxysilane and aminopropyltriethoxysilane.

[0019] In some embodiments, the method for preparing the light diffuser comprises the following steps: fully mixing epoxy acrylate, allyl diglycol dicarbonate and a curing agent, and performing a curing reaction to obtain the light diffuser.

[0020] The second object of the present application is to provide a method for manufacturing the Mini LED backlight module, comprising the following steps:

[0021] S1. Preparation of diffusion plate

[0022] Prepare materials according to the weight composition of the coating liquid for forming the coating; mix and stir the photoinitiator, diluent, polyurethane acrylate, and grafting agent evenly under light-free conditions, and then add a light diffuser and modified hollow mesoporous silica to obtain a coating liquid;

[0023] The coating liquid is evenly applied on a PET film, and then cured under a 100W ultraviolet lamp for 10-15 minutes to form a film, and after being taken out, the other side of the PET film is also cured to form a film, thereby preparing a light diffusion film;

[0024] S2. Assemble the backlight module

[0025] The display screen, prism film, diffusion plate, LED lamp and reflective film are assembled from top to bottom to produce a backlight module.

[0026] The beneficial effects of this application are:

[0027] 1. The backlight module described in the present application is prepared by preparing a backlight plate with high light transmittance, high haze and good light diffusion. The backlight plate can provide more uniform light distribution, reduce "light spots" or "hot spots" caused by excessive local light intensity, thereby reducing eye fatigue and pressure caused by long-term viewing of the display screen, and has a better healthy eye protection effect.

[0028] 2. The backlight module described in the present application has a diffusion plate that exhibits good resistance to UV aging, which helps to increase the service life of the backlight module. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0030] Figure 1 This is a schematic diagram of the structure of the backlight module described in this application;

[0031] Among them: 1. Display screen; 2. Prismatic film; 3. Diffusion plate; 4. LED lamp; 5. Reflective film. Specific implementation manners

[0032] For the convenience of those skilled in the art to understand, the present invention will be further described below in conjunction with embodiments. The content mentioned in the implementation manners is not a limitation to the present invention.

[0033] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. As used herein, the singular forms "a", "an", "one" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise. Further understanding, when "including" is used in this specification, it specifies the stated features, integers, steps, operations, elements and / or components, but does not exclude the existence or addition of one or more other features, integers, steps, operations, elements, components and / or their combinations.

[0034] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. Further understanding, terms, such as those defined in a commonly used dictionary, are interpreted in accordance with their meanings in the context of the relevant field and are not in an idealized or overly formal sense unless clearly defined as such herein.

[0035] The exemplary inventions described herein may appropriately lack any one or more of the element limitations that are not specifically disclosed herein. Therefore, terms such as "comprising", "including", "containing", etc. should be understood broadly and non-restrictively. Additionally, the terms of expression used herein are for description without limitation, and it is not intended to use these terms of expression that do not include any equivalent characteristics, but only to describe some of their characteristics. However, according to the rights, various modifications are possible within the scope of the present invention. Therefore, although the present invention has been specifically disclosed through preferred embodiments and optional features, modifications to the present invention as embodied herein may be recorded by those skilled in the art, and such modifications and variations are considered to be within the scope of the present invention.

[0036] The raw materials or reagents used in the embodiments and comparative examples of the present invention are all purchased from mainstream manufacturers in the market. For those without indicating the manufacturer or concentration, they are all raw materials or reagents of analytical purity grade that can be obtained conventionally. As long as they can play the expected role, there is no special limitation. The instrument equipment used in this embodiment is all purchased from major manufacturers in the market. As long as it can play the expected role, there is no special limitation. For those not indicating specific techniques or conditions in this embodiment, they are carried out according to the techniques or conditions described in the literature in this field or according to the product specifications.

[0037] Glossary of terms:

[0038] Display screen: The display screen is a key part of the display device and is responsible for converting electrical signals or digital signals into visible images. In the backlight module, the display screen (such as an LCD liquid crystal display screen) itself does not emit light, but relies on the light provided by the backlight module to display images. Working process: When an electrical signal is input into the display screen, the liquid crystal molecules will adjust their arrangement according to the signal, thereby allowing or blocking the light emitted by the backlight module to pass through and form an image.

[0039] Prismatic film: The prismatic film is an optical film mainly used to enhance the directivity of light and improve brightness. Working process: In the backlight module, the prismatic film is usually placed above the diffusion film to further converge and direct the diffused light to the display screen to improve the brightness and contrast of the picture.

[0040] Diffusion plate: The diffusion plate is located above the LED lamp. When the light emitted by the LED lamp irradiates the diffusion plate, the tiny particles or structures in the coating will scatter the light in all directions, thereby enhancing the uniformity and softness of the light. At the same time, the diffusion plate can also play a certain role in heat insulation and protection, reducing the impact of the heat generated by the LED lamp on the surrounding components.

[0041] LED lamp: An LED (light-emitting diode) is a semiconductor device that can convert electrical energy into light energy, with the advantages of high efficiency, energy saving, and environmental protection. In the backlight module, the LED lamp serves as a light source to provide illumination light. Working process: When an electric current passes through the PN junction of the LED chip, electrons and holes recombine to release energy and emit light in the form of photons. In a Mini LED backlight module, multiple Mini LED chips are densely arranged to jointly emit light, and the light is diffused and homogenized through components such as the diffusion film.

[0042] Reflection film: Usually located at the bottom of the backlight module, adjacent to the LED lamp board, it is used to reflect the part of the light emitted by the LED lamp that is not directly utilized back upwards, so that it can pass through components such as the diffusion plate again for diffusion and homogenization, and finally irradiate the display screen.

[0043] Polyurethane acrylate 5320, analytical pure, from Jiangmen Hengguang New Materials Co., Ltd.

[0044] Traditional Mini LED backlight modules may have problems with uneven light distribution, resulting in too high local light intensity and affecting visual comfort; when the backlight module needs to be exposed or operate for a long time, the diffusion plate may age, affecting the performance and lifespan of the backlight module. To solve the above problems, this application provides as Figure 1The shown Mini LED backlight module for healthy eye protection includes a Mini LED light board and a diffusion plate 3 disposed above the Mini LED light board. The diffusion plate 3 includes a base material and coatings applied on both sides of the base material; the base material is a PET film; the coating is a coating containing modified hollow mesoporous silica.

[0045] Specifically, the Mini LED backlight module is sequentially provided with a display screen 1, a prism film 2, a diffusion plate 3, an LED lamp 4, and a reflection film 5 assembled together from top to bottom.

[0046] In some embodiments, the coating solution for forming the coating includes the following raw materials in parts by weight:

[0047] 20 - 30 parts of a light diffusing agent, 10 - 20 parts of modified hollow mesoporous silica, 0.5 - 0.8 parts of a photoinitiator, 20 - 30 parts of a diluent, 10 - 20 parts of polyurethane acrylate, and 5 - 8 parts of a grafting agent.

[0048] The modified hollow mesoporous silica has a pore diameter of 1 - 15 nm; the photoinitiator is any one of 2 - hydroxy - 2 - methyl - 1 - phenyl - 1 - propanone and 4 - methylstyryldiphenyl iodonium salt. The diluent is dipropylene glycol diacrylate. The grafting agent is any one of 2 - hydroxyethyl methacrylate and glycidyl methacrylate.

[0049] Specifically, the parts by weight of the light diffusing agent are 20 - 30 parts. For example, the parts by weight of the light diffusing agent can be any value among 20 parts, 21 parts, 23 parts, 25 parts, 26 parts, 28 parts, and 30 parts, as long as it is within 20 - 30 parts (including the end point values).

[0050] Specifically, the parts by weight of the modified hollow mesoporous silica are 10 - 20 parts. For example, the parts by weight of the modified hollow mesoporous silica can be any value among 10 parts, 11 parts, 13 parts, 15 parts, 16 parts, 18 parts, and 20 parts, as long as it is within 10 - 20 parts (including the end point values).

[0051] Specifically, the parts by weight of the photoinitiator are 0.5 - 0.8 parts. For example, the parts by weight of the photoinitiator can be any value among 0.5 parts, 0.6 parts, 0.7 parts, and 0.8 parts, as long as it is within 0.5 - 0.8 parts (including the end point values).

[0052] Specifically, the parts by weight of the diluent are 20 - 30 parts. For example, the parts by weight of the diluent can be any value among 20 parts, 21 parts, 23 parts, 25 parts, 26 parts, 28 parts, and 30 parts, as long as it is within 20 - 30 parts (including the end point values).

[0053] Specifically, the weight portion of polyurethane acrylate is 10 - 20 parts. For example, the weight portion of polyurethane acrylate can be any value among 10 parts, 11 parts, 13 parts, 15 parts, 16 parts, 18 parts, and 20 parts, as long as it is within the range of 10 - 20 parts (including the end values).

[0054] Specifically, the weight portion of the grafting agent is 5 - 8 parts. For example, the weight portion of the grafting agent can be any value among 20 parts, 21 parts, 23 parts, 25 parts, 26 parts, 28 parts, and 30 parts, as long as it is within the range of 5 - 8 parts (including the end values).

[0055] Specifically, the weight portion of the light diffusing agent is 20 - 30 parts. For example, the weight portion of the light diffusing agent can be any value among 5 parts, 6 parts, 7 parts, and 8 parts, as long as it is within the range of 20 - 30 parts (including the end values).

[0056] In this application, the addition of grafting agents such as 2 - hydroxyethyl methacrylate and glycidyl methacrylate helps to improve the overall transparency of the coating, thereby maintaining a high light transmittance. The grafting agents can form a stable cross - linked structure during the curing process of the coating, reducing light scattering and facilitating the passage of light. At the same time, the grafting agents can improve the interfacial bonding force between the coating and the PET film substrate, enabling the coating to adhere more firmly to the PET film. The grafting agents prevent the coating from peeling or detaching during use, improving the overall durability and stability of the backlight module.

[0057] In this application, the modified hollow mesoporous silica (with a pore size of 1 - 15 nm), with its unique mesoporous structure and surface modification, can significantly increase the haze of the coating while ensuring a certain light transmittance. These tiny pore structures can effectively scatter light, making the light more evenly distributed and avoiding "light spots" or "hot spots" caused by excessive local light intensity. The hollow mesoporous structure enables the silica particles to scatter light more effectively, having better light diffusion performance compared to traditional solid particles. In addition, surface modification (such as using γ - methacryloxypropyltrimethoxysilane and aminopropyltriethoxysilane) enhances the compatibility between the silica and the coating, further improving the light diffusion effect.

[0058] In this application, the light diffusing agent can form multiple tiny scattering centers in the coating. These scattering centers can effectively scatter the light, making the light evenly distributed in the backlight module. The addition of the light diffusing agent significantly improves the light diffusion effect of the backlight module and reduces the phenomenon of local light concentration.

[0059] In some embodiments, the method for preparing the modified hollow mesoporous silica includes the following steps:

[0060] Take 1g of nano-silica, add it to 90mL of water for dispersion, then add 20ml of 10-15mg / ml hexadecyltrimethylammonium bromide ethanol solution, stir at room temperature for 2-3h, add 5-6g of anhydrous sodium carbonate, stir at 35°C for 12h, then heat to 50°C, stir for another 24h, after the reaction is completed, post-treat to obtain hollow mesoporous nano-silica;

[0061] 0.5 g of hollow mesoporous nano-silica and 1 g of a coupling agent are mixed thoroughly and stirred at room temperature for 24-36 hours to obtain modified hollow mesoporous silica. The coupling agent is any one of γ-methacryloxypropyltrimethoxysilane and aminopropyltriethoxysilane.

[0062] Specifically, hexadecyltrimethylammonium bromide is added to the nano-silicon dioxide dispersion as a template to help form a hollow mesoporous structure.

[0063] The prepared hollow mesoporous nano-silica has a large specific surface area and pore volume, which makes them have excellent scattering properties in light diffusers, which helps to improve the light uniformity of the backlight module; the hollow mesoporous structure can effectively scatter light and reduce the direct penetration of light, thereby improving the light diffusion effect of the backlight module and avoiding "light spots" or "hot spots" caused by excessive local light intensity; the hollow mesoporous nano-silica has better chemical stability, which helps to improve the service life of the backlight module.

[0064] In some embodiments, the method for preparing the light diffuser comprises the following steps: fully mixing epoxy acrylate, allyl diglycol dicarbonate and a curing agent, and performing a curing reaction to obtain the light diffuser.

[0065] Specifically, the preparation method of the light diffuser includes the following steps: fully mixing 1g of epoxy acrylate, 6g of allyl diglycol dicarbonate and 0.1g of benzoyl peroxide curing agent, performing a curing reaction at 60°C for 2h, and cooling to room temperature to obtain the light diffuser.

[0066] In the present application, the light diffuser is a microsphere mother solution, epoxy acrylate (epoxy acrylate) is used as a reactive component, triethylenetetramine (triethylenetetramine) is used as a curing agent, and allyl diglycol dicarbonate (allyl diglycol dicarbonate) is used as a solvent phase. As the curing reaction begins, a chemical reaction occurs between epoxy acrylate and triethylenetetramine, resulting in changes in the chemical and physical properties of the system. The curing reaction causes the network structure formed by epoxy acrylate and triethylenetetramine to be incompatible with allyl diglycol dicarbonate, thereby inducing phase separation;

[0067] The phase separation process can follow two mechanisms: Spinodal Decomposition (SD) and Nucleation and Growth (NG). When the mass ratio of allyl diglycol dicarbonate to epoxy acrylate is 6:1 or less, the phase separation follows the SD mechanism, forming a microbicontinuous phase structure, and then the bicontinuous phase breaks up to form dispersed microspheres.

[0068] When the mass ratio of allyl diglycol dicarbonate to epoxy acrylate is 8:1 or more, the phase separation follows the NG mechanism, and the primary nuclei gradually grow and disperse in the solvent phase to form microspheres. Therefore, through the above preparation method, a diffusant for the microsphere mother liquor is prepared, and when added to the coating solution, it can form multiple tiny scattering centers in the coating and prevent the coating solution from agglomerating at the same time.

[0069] Provided is a method for manufacturing the above Mini LED backlight module, including the following steps:

[0070] S1. Prepare a diffusion plate

[0071] Prepare materials according to the weight portion composition of the coating solution for forming the coating; mix and stir evenly the photoinitiator, diluent, polyurethane acrylate, and grafting agent under lightless conditions, and then add the light diffusant and modified hollow mesoporous silica to obtain the coating solution;

[0072] Apply the coating solution evenly on the PET film, and then cure it under a 100W ultraviolet lamp for 10 - 15 minutes to form a film. After taking it out, cure it to form a film on the other side of the PET film, thereby obtaining a light diffusion film;

[0073] S2. Assemble the backlight module

[0074] Assemble from top to bottom in the order of display screen, prism film, diffusion plate, LED lamp, and reflection film to manufacture the backlight module.

[0075] For the specific assembly method, it can be carried out in the conventional way of a mini LED backlight module.

[0076] Through the following preparation examples, examples and comparative examples, the backlight module and diffusion plate described in this application are further elaborated

[0077] Preparation Example 1

[0078] The preparation method of hollow mesoporous nano - silica includes the following steps:

[0079] Quickly add 10 ml of tetraethoxysilane to a mixture composed of 100 ml of ethanol, 15 ml of deionized water, and 4 ml of ammonia water solution (25%), then stir for another 12 hours, perform centrifugal separation to obtain the separated solid, and then wash the separated solid with deionized water and ethanol, and dry it at 150 °C for 10 h to obtain nano-silica.

[0080] Take 1 g of nano-silica, add it to 90 mL of water for dispersion, then add 20 ml of an ethanol solution of cetyltrimethylammonium bromide with a concentration of 10 mg / ml, stir at room temperature for 2 h, add 5 g of anhydrous sodium carbonate, stir at 35 °C for 12 h, then raise the temperature to 50 °C and stir for another 24 h. After the reaction is completed, perform centrifugal separation, and then wash the separated solid with deionized water and ethanol, and dry it at 120 °C for 12 h to obtain hollow mesoporous nano-silica.

[0081] Preparation Example 2

[0082] A preparation method of a light diffusing agent, comprising the following steps: fully mix 1 g of epoxy acrylate, 6 g of allyl diglycol dicarbonate, and 0.1 g of benzoyl peroxide curing agent, and carry out a curing reaction at 60 °C for 2 h, and then cool to room temperature to obtain the light diffusing agent.

[0083] The reaction process involved is:

[0084]

[0085] Example 1

[0086] A manufacturing method of a diffusion plate, comprising the following steps:

[0087] Prepare materials according to the weight portion composition of the coating liquid for forming the coating; mix 0.5 part of 2-hydroxy-2-methyl-1-phenyl-1-propanone, 20 parts of dipropylene glycol diacrylate, 10 parts of polyurethane acrylate, and 5 parts of 2-hydroxyethyl methacrylate evenly under lightless conditions; then add 20 parts of the light diffusing agent (Preparation Example 2) and 10 parts of modified hollow mesoporous silica, and mix them fully to obtain the coating liquid;

[0088] Apply the coating liquid evenly on the PET film, and then cure it under a 100 W ultraviolet lamp for 10 min to form a film. After taking it out, cure it to form a film on the other side of the PET film, thereby obtaining a light diffusing film; the thickness of the PET film is controlled at 50 μm, and after the coating liquid on one side is cured, the thickness is 10 - 11 μm.

[0089] Among them, the manufacturing method of the modified hollow mesoporous silica includes the following steps:

[0090] Take 0.5 g of hollow mesoporous nano-silica (Preparation Example 1), add it to 50 ml of absolute ethanol, ultrasonically disperse for 30 min, then add 1 g of γ-methacryloxypropyltrimethoxysilane and mix well. Stir at room temperature for 24 h, perform centrifugal separation, and then wash the separated solid with deionized water and ethanol, and dry at 80 °C for 20 h to obtain hollow mesoporous nano-silica.

[0091] Example 2

[0092] A method for manufacturing a diffusion plate, comprising the following steps:

[0093] Prepare materials according to the weight parts composition of the coating liquid for forming the coating; mix 0.8 parts of 4-methylstyryldiphenyl iodonium salt, 30 parts of dipropylene glycol diacrylate, 20 parts of polyurethane acrylate, and 8 parts of glycidyl methacrylate uniformly under lightless conditions; then add 30 parts of a light diffusing agent (Preparation Example 2) and 20 parts of modified hollow mesoporous silica, and mix well to obtain a coating liquid;

[0094] Apply the coating liquid evenly on a PET film, then cure it for 15 min under a 100 W ultraviolet lamp to form a film, take it out and cure it to form a film on the other side of the PET film, thereby obtaining a light diffusing film; the thickness of the PET film is controlled at 50 μm, and after curing the coating liquid on one side, the thickness is 10 - 11 μm.

[0095] Among them, the method for manufacturing modified hollow mesoporous silica comprises the following steps:

[0096] Take 0.5 g of hollow mesoporous nano-silica (Preparation Example 1), add it to 50 ml of absolute ethanol, ultrasonically disperse for 30 min, then add 1 g of aminopropyltriethoxysilane and mix well. Stir at room temperature for 36 h, perform centrifugal separation, and then wash the separated solid with deionized water and ethanol, and dry at 80 °C for 20 h to obtain hollow mesoporous nano-silica.

[0097] Example 3

[0098] A method for manufacturing a diffusion plate, comprising the following steps:

[0099] Prepare materials according to the weight parts composition of the coating liquid for forming the coating; mix 0.6 parts of 2-hydroxy-2-methyl-1-phenyl-1-propanone, 25 parts of dipropylene glycol diacrylate, 15 parts of polyurethane acrylate, and 7 parts of glycidyl methacrylate uniformly under lightless conditions; then add 25 parts of a light diffusing agent (Preparation Example 2) and 15 parts of modified hollow mesoporous silica, and mix well to obtain a coating liquid;

[0100] Apply the coating solution evenly on the PET film, and then cure it under a 100W ultraviolet lamp for 13 minutes to form a film. After taking it out, cure it to form a film on the other side of the PET film as well, thereby obtaining a light diffusing film; the thickness of the PET film is controlled at 50μm, and after curing the coating solution on one side, the thickness is 10 - 11μm.

[0101] Among them, the preparation method of the modified hollow mesoporous silica includes the following steps:

[0102] Take 0.5g of hollow mesoporous nano-silica (Preparation Example 1), add it to 50ml of absolute ethanol, ultrasonically disperse it for 30 minutes, then add 1g of aminopropyltriethoxysilane and mix well. Stir at room temperature for 30h, carry out centrifugal separation, then wash the separated solid with deionized water and ethanol, and dry it at 80°C for 20h to obtain hollow mesoporous nano-silica.

[0103] Example 4

[0104] The manufacturing method of the diffusion plate includes the following steps:

[0105] Prepare materials according to the weight fraction composition of the coating solution for forming the coating; mix 0.6 part of 4-methylstyryldiphenyl iodonium salt, 22 parts of dipropylene glycol diacrylate, 12 parts of polyurethane acrylate, and 6 parts of 2-hydroxyethyl methacrylate evenly under lightless conditions; then add 21 parts of the light diffusing agent (Preparation Example 2) and 12 parts of the modified hollow mesoporous silica, and mix well to obtain the coating solution;

[0106] Apply the coating solution evenly on the PET film, and then cure it under a 100W ultraviolet lamp for 11 minutes to form a film. After taking it out, cure it to form a film on the other side of the PET film as well, thereby obtaining a light diffusing film; the thickness of the PET film is controlled at 50μm, and after curing the coating solution on one side, the thickness is 10 - 11μm.

[0107] Among them, the preparation method of the modified hollow mesoporous silica includes the following steps:

[0108] Take 0.5g of hollow mesoporous nano-silica (Preparation Example 1), add it to 50ml of absolute ethanol, ultrasonically disperse it for 30 minutes, then add 1g of aminopropyltriethoxysilane and mix well. Stir at room temperature for 26h, carry out centrifugal separation, then wash the separated solid with deionized water and ethanol, and dry it at 80°C for 20h to obtain hollow mesoporous nano-silica.

[0109] Example 5

[0110] The manufacturing method of the diffusion plate includes the following steps:

[0111] Prepare materials according to the weight composition of the coating liquid for forming the coating; mix 0.7 parts of 4-methylstyryldiphenyl iodonium salt, 29 parts of dipropylene glycol diacrylate, 18 parts of polyurethane acrylate, and 7 parts of glycidyl methacrylate evenly under lightless conditions; then add 28 parts of a light diffusing agent (Preparation Example 2) and 18 parts of modified hollow mesoporous silica, and mix thoroughly to obtain the coating liquid;

[0112] Apply the coating liquid evenly on the PET film, and then cure it for 14 minutes under a 100W ultraviolet lamp to form a film. After taking it out, cure it to form a film on the other side of the PET film, thereby obtaining a light diffusing film; the thickness of the PET film is controlled at 50 μm, and after curing the coating liquid on one side, the thickness is 10 - 11 μm.

[0113] Among them, the manufacturing method of the modified hollow mesoporous silica includes the following steps:

[0114] Take 0.5 g of hollow mesoporous nano-silica (Preparation Example 1), add it to 50 ml of absolute ethanol, ultrasonically disperse it for 30 minutes, then add 1 g of γ-methacryloxypropyltrimethoxysilane and mix thoroughly. Stir at room temperature for 33 h, perform centrifugal separation, and then wash the separated solid with deionized water and ethanol, and dry it at 80 °C for 20 h to obtain hollow mesoporous nano-silica.

[0115] Comparative Example 1

[0116] The manufacturing method of the diffusion plate includes the following steps: Do not add a grafting agent to the coating liquid, and the other conditions are the same as in Example 1.

[0117] Comparative Example 2

[0118] The manufacturing method of the diffusion plate includes the following steps: Do not add modified hollow mesoporous nano-silica to the coating liquid, and the other conditions are the same as in Example 1.

[0119] Comparative Example 3

[0120] The manufacturing method of the diffusion plate includes the following steps: Do not add a light diffusing agent to the coating liquid, and the other conditions are the same as in Example 1.

[0121] Perform the following performance tests on the diffusion plates prepared in the above Examples 1 - 5 and Comparative Examples 1 - 3, and summarize the test results in Table 2;

[0122] Transmittance and haze: Sampling is carried out according to 4.2 in the text of GB / T 2410 - 2008 "Determination of Transmittance and Haze of Transparent Plastics", and the transmittance and haze of the light diffusing film are tested by the spectrophotometer method of Method B in 7.2;

[0123] Ultraviolet aging test chamber test: The aging time is 0 - 240 h, and samples are taken and observed every 24 h; A color difference meter is used to test the change of the color difference value (ΔE) of the film material during the aging process, and it is evaluated according to the color change degree and color change grade evaluation criteria specified in GB / T 1766 - 1995 (Table 1);

[0124] Table 1

[0125] Color change level Color difference value (ΔE) Degree of color change 0 ≤1.5 No color change 1 1.6～3.0 Very slight color change 2 3.1～6.0 Slight color change 3 6.1～9.0 Obvious color change 4 9.1～12.0 Large color change 5 ＞12.0 Severe color change

[0126] Light uniformity detection: Use a color analyzer to detect the uniformity index; The uniformity index represents the consistency of color distribution, and the lower the value, the more uniform the color distribution.

[0127] Table 2

[0128]

[0129]

[0130] As can be seen from Table 2, the light transmittance of the diffusion plates prepared in Examples 1 - 5 of the present application is all above 90%, which indicates that these diffusion plates have high light transmittance performance and are beneficial to maintaining the brightness and clarity of the display device; The haze of the diffusion plates prepared in Examples 1 - 5 of the present application is all above 90%, indicating that the coating design effectively improves the light scattering effect; The uniformity index of the diffusion plates prepared in Examples 1 - 5 of the present application is all lower than 1.0, showing very excellent light uniformity. The diffusion plates prepared in Examples 1 - 5 of the present application show "no color change", indicating that these diffusion plates have excellent aging resistance.

[0131] For the diffusion plate of Comparative Example 1, after the grafting agent is missing, it significantly changes color during the aging test, and the diffusion, haze and light uniformity of the diffusion plate decrease.

[0132] For the diffusion plate of Comparative Example 2, after the modified hollow mesoporous nano - silica is missing, the light transmittance significantly decreases.

[0133] For the diffusion plate of Comparative Example 3, the light diffusing agent, haze and light uniformity significantly decrease.

[0134] The above - mentioned embodiments are the preferred implementation solutions of the present invention. In addition, the present invention can also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.

Claims

1. A Mini LED backlight module for healthy eye protection, comprising a Mini LED light board and a diffusion board arranged above the Mini LED light board, characterized in that, The diffusion plate includes a substrate and coatings coated on both surfaces of the substrate; the substrate is a PET film; the coatings are coatings containing modified hollow mesoporous silica; The coating liquid for forming the coatings includes the following raw materials in parts by weight: 20-30 parts of a light diffusing agent, 10-20 parts of modified hollow mesoporous silica, 0.5-0.8 parts of a photoinitiator, 20-30 parts of a diluent, 10-20 parts of polyurethane acrylate, 5-8 parts of a grafting agent; The photoinitiator is any one of 2-hydroxy-2-methyl-1-phenyl-1-propanone and 4-methylstyryldiphenyl iodonium salt; The diluent is dipropylene glycol diacrylate; The grafting agent is any one of 2-hydroxyethyl methacrylate and glycidyl methacrylate; 2. The Mini LED backlight module according to claim 1, wherein The pore diameter of the modified hollow mesoporous silica is 1-15 nm; the thickness of the PET film is 50-80 μm; the thickness of the coatings is 10-15 μm.

3. The Mini LED backlight module according to claim 1, characterized in that, The preparation method of the modified hollow mesoporous silica includes the following steps: Take 1 g of nano-silica, add it to 90 mL of water for dispersion, then add 20 ml of an ethanol solution of cetyltrimethylammonium bromide with a concentration of 10-15 mg / ml, stir at room temperature for 2-3 h, add 5-6 g of anhydrous sodium carbonate, stir at 35 °C for 12 h, then raise the temperature to 50 °C and stir for another 24 h. After the reaction is completed, post-treatment is carried out to obtain hollow mesoporous nano-silica; Take 0.5 g of hollow mesoporous nano-silica and 1 g of a coupling agent and mix them thoroughly, stir at room temperature for 24-36 h to obtain modified hollow mesoporous silica.

4. The Mini LED backlight module according to claim 3, characterized in that, The coupling agent is any one of γ-methacryloxypropyltrimethoxysilane and aminopropyltriethoxysilane; 5. The Mini LED backlight module according to claim 1, wherein The preparation method of the light diffusing agent includes the following steps: Mix epoxy acrylate, allyl diglycol dicarbonate and a curing agent thoroughly and carry out a curing reaction to obtain the light diffusing agent.

6. The manufacturing method of the Mini LED backlight module according to any one of claims 1-5, characterized in that, Including the following steps: S1. Prepare the diffusion plate Prepare materials according to the weight part composition of the coating liquid for forming the coatings; mix and stir the photoinitiator, diluent, polyurethane acrylate, and grafting agent evenly under lightless conditions, and then add the light diffusing agent and modified hollow mesoporous silica to obtain the coating liquid; Evenly apply the coating liquid on the PET film, then cure it into a film under a 100 W ultraviolet lamp for 10-15 min, take it out and cure it into a film on the other side of the PET film to obtain the light diffusion plate; S2. Assemble the backlight module Assemble from top to bottom in the order of a display screen, a prism film, a diffusion plate, an LED lamp, and a reflective film to produce the backlight module.

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