A directly attached light control film for vehicle and light control display module

Abstract

The application discloses a directly-pasted vehicle-mounted light control film and a light control display module, wherein the directly-pasted vehicle-mounted light control film comprises, from top to bottom, a bonding layer, a low-refraction layer, a fogging layer, a first substrate layer, a light control layer and a second substrate layer; the refractive index of the bonding layer is n1, the refractive index of the low-refraction layer is n2, and the refractive index of the fogging layer is n3; |n1-n2|>0.05, |n3-n2|>0.05, and |n1-n3|<0.03. The low-refraction layer is introduced between the fogging layer and the bonding layer, and the refractive index of the low-refraction layer is significantly lower than that of the bonding layer and the fogging layer. Through the design, the light is obviously refracted on the interface between the fogging layer and the low-refraction layer and the interface between the low-refraction layer and the bonding layer, the light is scattered, the fogging effect is enhanced, and excellent visual shielding performance is provided. In addition, the vehicle-mounted light control film can be directly pasted with the display module, so that the production process is simplified, the manufacturing cost is reduced, and the deformation problems, such as warping, of the vehicle-mounted light control film in the traditional method are avoided.

Description

Technical Field

[0001] This invention belongs to the field of automotive light control film technology, and particularly relates to a direct-adhesion automotive light control film and a light control display module. Background Technology

[0002] With the continuous development of the automotive industry, in-vehicle display technology is also constantly advancing. To enhance the driving experience and safety, automotive light control film, as a key component, is widely used in in-vehicle displays and other optical devices. The main function of automotive light control film is to control the passage of light to ensure that the in-vehicle screen can provide a clear, glare-free image under different lighting conditions.

[0003] However, the application of existing automotive light control films has certain limitations, especially in the selection of installation locations. They are typically required to be used in backlit environments, which places strict requirements on the physical properties of the materials, including but not limited to warpage performance, coefficient of thermal expansion, and shrinkage rate. Since light control films are composed of grating materials and a substrate, and the thermal properties of these two components differ significantly, the films are prone to deformation problems such as warping and wrinkling during long-term use, especially in high-temperature or temperature-fluctuation environments. These problems not only affect the functional performance of the light control film but also reduce user satisfaction.

[0004] Therefore, there is an urgent need to develop a direct-attach automotive light control film and a light control display module to address the shortcomings of existing technologies. Summary of the Invention

[0005] The inventors of this application have researched directly bonding the light-control film to the module to form an integrated structure. This can effectively disperse external pressure and internal thermal stress, reduce local stress concentration caused by relative movement between different materials, and reduce the interaction force between the grating material and the substrate even under extreme temperature conditions, thereby reducing the risk of deformation. However, this method faces a significant challenge: if the atomizing layer (usually an embossed or microbead structure) in the light-control film directly contacts the adhesive layer, the adhesive layer will cover the entire atomizing layer. Furthermore, because the refractive indices of both are similar, light will not undergo necessary refraction at the interface between the atomizing layer and the adhesive layer, causing the atomizing layer to lose its shielding effect and failing to achieve the expected optical control function.

[0006] In view of the above problems, the purpose of this invention is to provide a direct-attach automotive light control film and a light control display module. The automotive light control film can be directly attached to the display module, which not only simplifies the production process and reduces manufacturing costs, but also avoids the warping and other deformation problems that are common in automotive light control films in traditional methods. At the same time, the automotive light control film can maintain good haze characteristics and provide excellent blemish masking effect.

[0007] To achieve the above objectives, the first aspect of the present invention provides a direct-attach automotive light control film, which comprises, from top to bottom, an adhesive layer, a low-reflection layer, an atomizing layer, a first substrate layer, a light control layer, and a second substrate layer. The refractive index of the adhesive layer is n1, the refractive index of the low-reflection layer is n2, and the refractive index of the atomizing layer is n3, where |n1-n2|>0.05, |n3-n2|>0.05, and |n1-n3|<0.03.

[0008] Because the refractive indices of the bonding layer and the atomizing layer are very close, light undergoes almost no significant refraction at the interface between these two layers, resulting in poor atomization and consequently affecting the shielding performance of the atomizing layer. Therefore, this invention introduces a low-refractive-index layer between the atomizing layer and the bonding layer, ensuring that |n1-n2|>0.05, |n3-n2|>0.05, and |n1-n3|<0.03; that is, the refractive index of the low-refractive-index layer is significantly lower than that of the bonding layer and the atomizing layer. Through this design... ， Light undergoes significant refraction at the interfaces between the atomizing layer and the low-refractive layer, as well as at the interfaces between the low-refractive layer and the adhesive layer, resulting in light scattering and enhanced atomization, thus providing excellent visual shielding performance. Furthermore, the automotive light control film of this invention can be directly bonded to the display module, simplifying the production process, reducing manufacturing costs, and avoiding the warping and deformation problems that are common in traditional automotive light control films.

[0009] Furthermore, the adhesive layer of the present invention is selected from any one of acrylic adhesive, PU adhesive, and epoxy adhesive. These materials all provide high-strength adhesion and exhibit good compatibility with various substrates, ensuring a firm bond between the light control film and the display module. Specifically, the refractive index of acrylic adhesive (acrylate adhesive) is 1.48–1.52; the refractive index of PU adhesive (polyurethane adhesive) is 1.50–1.55; and the refractive index of epoxy adhesive is 1.50–1.60.

[0010] Furthermore, the thickness of the adhesive layer in this invention is 20–100 μm. Specifically, the thickness of the adhesive layer may be, but is not limited to, 20 μm, 40 μm, 60 μm, 80 μm, or 100 μm.

[0011] Furthermore, the haze of the atomizing layer of the present invention is 20% to 60%. A haze value within this range is neither too low, resulting in insufficient shading, nor too high, affecting light transmittance. The specific material selection for the atomizing layer can be flexibly determined by those skilled in the art based on actual application requirements, as long as the selected material meets the aforementioned haze requirements.

[0012] Furthermore, the refractive index of the low-refractive layer of the present invention is 1.3 to 1.4.

[0013] Furthermore, the thickness of the low-fold layer of the present invention is 5 to 50 μm. For example, the thickness of the low-fold layer may be, but is not limited to, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, or 50 μm.

[0014] Furthermore, the low-refractive-index layer of the present invention comprises, by weight, 10-40 parts porous hollow silica resin, 30-70 parts silsesquioxane resin, 2-10 parts dispersant, 1-5 parts leveling agent, 0.5-3 parts antioxidant, and 0.1-1 parts initiator. In the prior art, common low-refractive-index resins are mainly fluorinated polymers (such as polytetrafluoroethylene and fluoroacrylates). These materials, due to the low polarizability of fluorine atoms, can achieve low refractive indices (typically between 1.3 and 1.4), and are therefore widely used in the manufacture of low-refractive-index coatings. However, with increasingly stringent environmental standards, the application of fluorinated resins is facing more and more restrictions because their production and use may have adverse environmental impacts. Based on this, this application uses siloxane resin to achieve low refractive index performance, that is, introducing a hollow silica structure into the resin system. Its unique hollow morphology significantly reduces the overall density of the resin, thereby ensuring excellent low-refractive-index characteristics and avoiding the environmental problems caused by the use of traditional fluorinated materials.

[0015] Furthermore, the content of the porous hollow silica resin of the present invention can be, but is not limited to, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, or 40 parts. Specifically, the porous hollow silica resin is a material with a special structure, its outer shell being silica (SiO2) and its interior filled with air. This material is characterized by micropores or mesopores on its outer shell, with pore sizes in the nanoscale range, which can significantly increase the specific surface area and adsorption performance of the material. Some organic resins can also be pre-adsorbed on the pores to increase the adsorption force. Specifically, the porosity of the porous hollow silica resin is 10-70%.

[0016] Furthermore, the content of the silsesquioxane resin of the present invention may be, but is not limited to, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, or 70 parts; specifically, the specific surface area of ​​the silsesquioxane resin is 400 to 1500 m². 2 / g.

[0017] Further, the content of the dispersant in this invention may be, but is not limited to, 2 parts, 4 parts, 6 parts, 8 parts, 9 parts, or 10 parts; specifically, the dispersant is DISPERBYK 102, DISPERBYK 108, DISPERBYK 115, DISPERBYK 118, DISPERBYK 140, DISPERBYK 142, DISPERBYK 145, DISPERBYK 160, DISPERBYK 164, DISPERBYK 170, DISPERBYK 174, DISPERBYK 180, DISPERBYK 184, DISPERBYK 191, DISPERBYK 194N, DISPERBYK 2001, DISPERBYK 2055, DISPERBYK 2150, DISPERBYK... At least one of BYK 2200, ANTITERRA 250, BYK P104, BYK 220S, BYK 154, BYK 9076, and BYK 9077. The dispersant can further improve the dispersibility of the hollow silica.

[0018] Furthermore, the content of the leveling agent of the present invention may be, but is not limited to, 1 part, 2 parts, 3 parts, 4 parts, or 5 parts; specifically, the leveling agent is one or more of BYK 300, BYK 301, BYK 302, BYK 331, BYK 335, BYK 306, BYK 330, BYK 341, BYK 344, BYK 307, BYK 333, and BYK 310. The leveling agent can further improve the smoothness of the low-fold layer surface.

[0019] Furthermore, the content of the antioxidant of the present invention may be, but is not limited to, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, or 3 parts; specifically, the antioxidant may be selected from hindered phenolic antioxidants or phospholipid antioxidants; more specifically, the antioxidant may be, but is not limited to, 2,6-di-tert-butylphenol (BHA) or 2,6-di-tert-butyl-4-methylphenol (BHT).

[0020] Furthermore, the initiator content of the present invention may be, but is not limited to, 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, or 1 part; specifically, the initiator is a UV initiator, such as, but not limited to, UV photoinitiator 819.

[0021] Furthermore, the preparation of the low-refractive-index layer of the present invention includes: mixing porous hollow silica resin, silsesquioxane resin, dispersant, leveling agent, antioxidant, initiator, and solvent to obtain a low-refractive-index resin; coating the low-refractive-index resin onto an atomized layer and drying it in an oven to remove the solvent; and then irradiating it with UV energy in the range of 800–1500 MJ to obtain the low-refractive-index layer. The solvent can be a polar solvent such as alcohols, ketones, glycols, furans, or amides, or a non-polar or weakly polar solvent such as alkanes, aromatic hydrocarbons, phenols, or halogenated hydrocarbons. Examples of alcohols include ethanol; ketones include cyclohexanone; diols include ethylene glycol and propylene glycol; furans include tetrahydrofuran; amides include dimethylformamide, dimethylacetamide, and N-methyl-2-pyrrolidone; alkanes include hexane and cyclohexane; aromatic hydrocarbons include toluene and xylene; phenols include cresol; and halogenated hydrocarbons include chloroform and dichlorobenzene.

[0022] Furthermore, the first substrate layer and the second substrate layer of the present invention are each individually selected from polyethylene terephthalate (PET), polyurethane (PU), polyvinyl chloride (PVC), polycarbonate (PC), polyimide (PI), and thermoplastic polyurethane (TPU).

[0023] Furthermore, the thickness of both the first substrate layer and the second substrate layer of the present invention is 5 to 300 μm. For example, the thickness of the first substrate layer may be, but is not limited to, 5 μm, 20 μm, 50 μm, 80 μm, 120 μm, 180 μm, 220 μm, 250 μm, 280 μm, or 300 μm; and the thickness of the second substrate layer may be, but is not limited to, 5 μm, 30 μm, 60 μm, 80 μm, 110 μm, 150 μm, 180 μm, 225 μm, 250 μm, 280 μm, or 300 μm.

[0024] Furthermore, the light control layer of the present invention includes alternating light-transmitting units and light-absorbing units of the same height, the distance between the light-transmitting units and the light-absorbing units is 30-60 μm, and the height between the light-transmitting units and the light-absorbing units is 50-200 μm; for example, the distance between the light-transmitting units and the light-absorbing units may be, but is not limited to, 30 μm, 40 μm, 50 μm, 60 μm, and the height of the light-transmitting units may be, but is not limited to, 50 μm, 70 μm, 90 μm, 110 μm, 130 μm, 150 μm, 180 μm, 200 μm.

[0025] Accordingly, a second aspect of the present invention also provides a light-controlled display module, including a display module and the aforementioned direct-attach automotive light-controlled film, wherein the adhesive layer is bonded to the display module. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the light-controlled display module of the present invention.

[0027] Figure 2 A schematic diagram of the structure of the direct-adhesion vehicle-mounted light control film of the present invention.

[0028] Figure 3 for Figure 2 A schematic diagram illustrating the light path after removing the low-fold layer from a direct-attach automotive light control film.

[0029] Figure 4 for Figure 2 A schematic diagram illustrating the light path principle of a direct-attach automotive light control film. Detailed Implementation

[0030] To illustrate the technical content, structural features, and effects of the present invention in detail, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0031] Please refer to Figure 1 This invention provides a light-controlled display module 30, which includes a direct-attach automotive light-control film 100 and a display module 200. Specifically, the direct-attach automotive light-control film 100 is directly bonded to the display module 200 to form an integrated structure. This effectively disperses external pressure and internal thermal stress, reduces local stress concentration caused by relative movement between different materials, and reduces the interaction force between the grating material and the substrate even under extreme temperature conditions, thereby reducing the risk of deformation. Therefore, this invention directly bonds the direct-attach automotive light-control film 100 and the display module 200, which not only simplifies the production process and reduces manufacturing costs, but also avoids the warping and other deformation problems that are prone to occur with automotive light-control films in traditional methods.

[0032] For optimal blemish concealing results, please refer to... Figure 2 This invention provides a direct-attach automotive light control film 100, which, from top to bottom, includes an adhesive layer 11, a low-reflection layer 12, an atomizing layer 13, a first substrate layer 14, a light control layer 15, and a second substrate layer 16. An adhesive layer 17 is provided between the light control layer 15 and the second substrate layer 16 to bond the two layers together. The adhesive layer 17 can specifically be OCA optical adhesive. The light control layer 15 includes alternating light-transmitting units 151 and light-absorbing units 152 of equal height. The spacing between the light-transmitting units 151 and light-absorbing units 152 is 30-60 μm, and the height of the light-transmitting units 151 and light-absorbing units 152 is 50-200 μm. Because the refractive indices of the adhesive layer 11 and the atomizing layer 13 are very close, light will hardly undergo significant refraction at the interface between these two layers (e.g., ...). Figure 3As shown in the figure, this results in poor atomization, which in turn affects the shielding performance of the atomization layer 13. Based on this, this application introduces a low-refractive-index layer 12 between the atomization layer 13 and the adhesive layer 11, ensuring that the absolute value of the difference between the refractive index n1 of the adhesive layer 11 and the refractive index n2 of the low-refractive-index layer 12 is greater than 0.05, the absolute value of the difference between the refractive index n3 of the atomization layer 13 and the refractive index n2 of the low-refractive-index layer 12 is greater than 0.05, and the absolute value of the difference between the refractive index n3 of the atomization layer 13 and the refractive index n1 of the adhesive layer 11 is less than 0.03. Through this design, light undergoes significant refraction at both the interface between the atomization layer 13 and the low-refractive-index layer 12 and the interface between the low-refractive-index layer 12 and the adhesive layer 11 (e.g., ...). Figure 4 As shown, the light is scattered, thereby enhancing the fogging effect and providing excellent visual occlusion performance.

[0033] The objectives, technical solutions, and beneficial effects of the present invention will be described in more detail below through specific embodiments.

[0034] The porous hollow silica resin used in the examples was purchased from Changxing Materials Industry Co., Ltd. The silsesquioxane resin used in the examples was dodecaphenyl-cage polysilsesquioxane (Dodecaphenyl POSS), as shown below, which was also purchased from Changxing Materials Industry Co., Ltd.

[0035]

[0036] Example 1

[0037] This embodiment provides a direct-adhesion automotive light control film, which, from top to bottom, includes an adhesive layer, a low-fold layer, a fogging layer, a first substrate layer, a light control layer, an adhesive layer, and a second substrate layer.

[0038] The adhesive layer has a thickness of 30 μm and is made of PU adhesive with a refractive index of 1.53.

[0039] The low-refractive-index layer has a thickness of 10 μm and a refractive index of 1.42; the formulation of the low-refractive-index layer is shown in Table 1.

[0040] The atomizing layer is made of acrylic material; it has a haze of 20% and a refractive index of 1.52.

[0041] The first substrate layer is 100 μm thick and is made of PET.

[0042] The light control layer includes alternating light-transmitting units and light-absorbing units of the same height, with a spacing of 40 μm between the light-transmitting units and light-absorbing units and a height of 100 μm between the light-transmitting units and light-absorbing units;

[0043] The bonding layer is made of OCA optical adhesive;

[0044] The second substrate layer is 200 μm thick and is made of PET.

[0045] The direct-attach automotive light control films of Examples 2-9 are basically the same as those of Example 1, except that the formulation and refractive index of the low-reflection layer and the haze of the atomization layer are different. The formulations of the low-reflection layers of Examples 2-9 are shown in Table 1, and the refractive index and haze of the atomization layer of Examples 2-9 are shown in Table 2.

[0046] Comparative Example 1

[0047] This comparative example provides a direct-adhesion automotive light control film, which, from top to bottom, includes an adhesive layer, a fogging layer, a first substrate layer, a light control layer, an bonding layer, and a second substrate layer.

[0048] The adhesive layer has a thickness of 30 μm and is made of PU adhesive with a refractive index of 1.53.

[0049] The atomizing layer is made of acrylic material, has a haze of 20%, and a refractive index of 1.52;

[0050] The first substrate layer is 100 μm thick and is made of PET.

[0051] The light control layer includes alternating light-transmitting units and light-absorbing units of the same height, with a spacing of 40µm between the light-transmitting units and light-absorbing units and a height of 100µm.

[0052] The bonding layer is made of OCA optical adhesive; the second substrate layer is 200μm thick and is made of PET.

[0053] The haze values ​​of the direct-adhesion automotive light control films of Examples 1-9 and Comparative Example 1 were tested using a haze meter, and the results are shown in Table 2.

[0054] Table 1

[0055]

[0056] Table 2

[0057]

[0058]

[0059] Based on the results shown in Table 2, it can be observed that the direct-attach automotive light control film of the present invention, by introducing a low-reflection layer between the atomizing layer and the adhesive layer and ensuring that the refractive index of the low-reflection layer is significantly lower than that of the adhesive layer and the atomizing layer, can effectively maintain the original haze of the light control film. This means that even after the direct-attach automotive light control film is bonded to the display module, it can still ensure high transparency and low light scattering, which is very beneficial for ensuring that users obtain a good visual effect.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A direct-adhesion automotive light control film, characterized in that, From top to bottom, it includes an adhesive layer, a low-refractive-index layer, a fogging layer, a first substrate layer, a light control layer, and a second substrate layer. The refractive index of the adhesive layer is n1, the refractive index of the low-refractive-index layer is n2, and the refractive index of the fogging layer is n3. |n1-n2|>0.05, |n3-n2|>0.05, and |n1-n3|<0.

03.

2. The direct-adhesion automotive light control film as described in claim 1, characterized in that, The adhesive layer is selected from any one of acrylic adhesive, PU adhesive, and epoxy adhesive.

3. The direct-adhesion automotive light control film as described in claim 1, characterized in that, The haze of the atomizing layer is 20-60%.

4. The direct-adhesion automotive light control film as described in claim 1, characterized in that, The refractive index of the low-refractive layer is 1.3 to 1.

4.

5. The direct-adhesion automotive light control film as described in claim 1, characterized in that, The thickness of the low-fold layer is 5–50 μm.

6. The direct-adhesion automotive light control film as described in claim 1, characterized in that, The low-fold layer comprises, by weight, 10-40 parts porous hollow silica resin, 30-70 parts silsesquioxane resin, 2-10 parts dispersant, 1-5 parts leveling agent, 0.5-3 parts antioxidant, and 0.1-1 parts initiator.

7. The direct-adhesion automotive light control film as described in claim 6, characterized in that, The porous hollow silica resin has a porosity of 10-70%; the silsesquioxane resin has a specific surface area of ​​400-1500 m². 2 / g.

8. The direct-adhesion automotive light control film as described in claim 1, characterized in that, The first substrate layer and the second substrate layer are each individually selected from PET, PU, ​​PVC, PC, PI, and TPU.

9. The direct-adhesion automotive light control film as described in claim 1, characterized in that, The light control layer includes alternating light-transmitting units and light-absorbing units of the same height, with a spacing of 30-60 μm between the light-transmitting units and the light-absorbing units, and a height of 50-200 μm between the light-transmitting units and the light-absorbing units.

10. A light-controlled display module, comprising a display module, characterized in that, It also includes the direct-adhesion vehicle light control film as described in any one of claims 1 to 9, wherein the adhesive layer is bonded to the display module.

Images