UV-cured microstructure release film and preparation method thereof

Abstract

The invention relates to a UV curing type microstructure release film and a preparation method thereof, and relates to the technical field of release liners.The release film comprises a base material layer and a release coating arranged on the base material layer; the release coating is prepared from the following materials in parts by weight: 60 to 80 parts of organic silicon oligomer, 10 to 20 parts of cross-linking agent, 5 to 10 parts of anchoring agent, 1 to 3 parts of flatting agent, 1 to 3 parts of defoaming agent and 2 to 8 parts of photoinitiator; the release coating is a microstructure release coating, the diameter of the microstructure of the microstructure release coating is 1-200 [mu] m, the ratio of the diameter to the height is 2: 1-100: 1, and the microstructure is a microlens structure. The release film has the advantages of ultralow release force and high residual adhesion rate through reasonably designed components and proportion and special microstructure design, and meanwhile, the coating curing rate of the release film is increased, and the release film has the advantages of rapid curing characteristic and improvement of production efficiency, so that the release film has wide applicability in application with high performance requirements, and has wide application prospects. And the usability and the production benefit of the product can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of release films, and in particular to a UV-curable microstructured release film and a preparation method thereof. Background Art

[0002] Coated release film is a functional film formed by coating a release material on the surface of a substrate layer, and is widely used in various industrial fields. Common coated release films include PET release film, BOPP release film, PE release film, PI release film, etc. The manufacturing process of these release film products usually includes coating the release glue material on the surface of different film substrate layers, and curing it through a thermal curing or UV curing process to obtain a release film with specific functions. Release films are widely used in industries such as waterproof materials, adhesive tapes, protective films, ceramic capacitors, polarizers, and die-cutting processing.

[0003] At present, most coated release films still use traditional thermal curing processes. This type of release film product usually has a planar structure, but it has certain limitations. First, the residual adhesion rate of traditional thermal curing release films is low, which makes the release agent easy to precipitate or transfer, thus affecting the stability and performance of the release film. In addition, in order to obtain lower peeling force, coatings with high silicon or fluorine content are often used, but these materials have obvious disadvantages. Although silicon materials can significantly reduce adhesion, they are prone to material transfer pollution, affecting subsequent processes and product quality; fluorine materials may bring environmental pollution risks, especially in long-term use, they may release harmful substances and cause ecological harm.

[0004] In addition to performance issues, the traditional thermal curing coating process also has serious environmental problems. The process often relies on organic solvents as a dissolving medium, which leads to solvent pollution. At the same time, the high temperature heating and long curing time required in the thermal curing process are also accompanied by large energy consumption, which not only increases production costs, but also puts a burden on the environment. Therefore, it is urgent to develop a new release film that is more environmentally friendly, energy-efficient and has excellent release performance. Summary of the invention

[0005] In order to improve the residual bonding rate, avoid excessive precipitation or transfer of the release agent to affect product application, and maintain a stable low release force, the present application provides a UV-curable microstructure release film and a preparation method thereof.

[0006] The present application provides a UV-curable microstructure release film and a preparation method thereof using the following technical solutions: A UV-curable microstructure release film comprises a substrate layer and a release coating disposed on the substrate layer; the materials of the release coating comprise, by weight: 60-80 parts of an organosilicon oligomer, 10-20 parts of a cross-linking agent, 5-10 parts of an anchoring agent, 1-3 parts of a leveling agent, 1-3 parts of a defoaming agent, and 2-8 parts of a photoinitiator; the release coating is a microstructure release coating, the diameter of the microstructure of the microstructure release coating is 1-200 um, the ratio of diameter to height is 2:1-100:1, and the microstructure is a microlens structure.

[0007] By adopting the above technical scheme and the above components and proportion design, the silicone oligomer has a lower surface energy, so that the release coating has good release performance; the use of the cross-linking agent enhances the tensile, tear and abrasion resistance of the release coating, and improves the durability of the release coating; the anchoring agent ensures good adhesion between the release coating and the substrate layer, and avoids the release coating from falling off during the use of the release film; the leveling agent and the defoaming agent work together to improve the surface quality of the release coating, making it smooth, uniform and bubble-free, further enhancing the release effect of the release film; the photoinitiator promotes the rapid curing of the release coating, reduces the production cycle, and improves the production efficiency; the UV-curable microstructure release film of the present application has a stable low release force and a high residual bonding rate through precise proportioning and microstructure design, while improving the durability and surface quality of the release film. Its rapid curing characteristics and the advantages of improving production efficiency make this release film widely applicable in applications with high performance requirements, and can significantly improve the product's performance and production benefits.

[0008] In a specific embodiment, the organosilicon oligomer is an acrylic modified siloxane oligomer.

[0009] By adopting the above technical solution, the acrylic modified siloxane oligomer provides a lower surface energy through the silicon-oxygen structure in its molecule, so that the release film can effectively prevent adhesion with the adhesive layer and has a reliable release effect.

[0010] In a specific embodiment, the acrylic modified silicone oligomer includes modified silicone containing double bonds, and has a weight average molecular weight of 5,000-20,000.

[0011] By adopting the above technical solution, the double bonds in the molecular structure of the oligomer enable the film surface to obtain good wettability. At the same time, the presence of the silicon-oxygen chain ensures excellent anti-adhesion properties, thereby ensuring a good release effect. The release coating can effectively avoid adhesion to the adhered adhesive layer and will not leave residues or damage the surface of the adhered adhesive layer during the peeling process.

[0012] In a specific embodiment, the crosslinking agent is vinyl polysiloxane.

[0013] By adopting the above technical solution, the above cross-linking agent has good UV curing properties and can quickly participate in the cross-linking reaction under UV light. This rapid curing property can significantly shorten the production time and improve production efficiency. The curing process is efficient and uniform, ensuring that the product has stable performance and quality in practical applications.

[0014] In a specific embodiment, the weight average molecular weight of the vinyl polysiloxane is 1000-3000.

[0015] By adopting the above technical scheme, the weight-average molecular weight of vinyl polysiloxane is 1000-3000, and the molecular chain length is moderate, which can ensure effective cross-linking between molecules without being too long to cause excessive viscosity; the moderate molecular weight helps to form a uniform cross-linking network during the UV curing process, thereby enhancing the mechanical properties of the cured release coating.

[0016] In a specific embodiment, the anchoring agent is one or more of a siloxane anchoring agent, a polyurethane anchoring agent, an acrylic anchoring agent, and an epoxy resin anchoring agent.

[0017] By adopting the above technical solution, the above types of anchoring agents can form a strong chemical bonding layer on the surface of the optical substrate layer, thereby improving the adhesion between the coating and the substrate layer, ensuring that the coating is not easy to fall off or peel off during use, and extending the service life.

[0018] In a specific embodiment, the leveling agent is one or more of a silicone leveling agent, a polyurethane leveling agent, an acrylic leveling agent, and a polyester leveling agent.

[0019] By adopting the above technical scheme, the above-mentioned leveling agents have the ability to reduce the surface tension of the coating, can effectively improve the flatness of the coating, reduce defects on the coating surface such as brush marks, bubbles, and sagging, can help the coating spread evenly during the coating process, and ensure a smooth coating surface.

[0020] In a specific embodiment, the defoaming agent is one or more of an organosilicon defoaming agent, a polyether defoaming agent, an olefin defoaming agent, and an alcohol defoaming agent.

[0021] By adopting the above technical solution, the above defoaming agent can reduce or eliminate the foam in the coating, adhesive or liquid system, prevent the influence of the foam on the coating or processing process, and can quickly destroy the existing foam and prevent the generation of new foam.

[0022] In a specific embodiment, the photoinitiator is one or more of 184, 1173, 819, 907, 651, 379, 369, TPO, 261, 250, 432, and 1176.

[0023] By adopting the above technical solution, the above photoinitiators can absorb ultraviolet light or visible light and stimulate the generation of free radicals or other active substances, thereby initiating a photocuring reaction. The use of these photoinitiators can improve the reaction speed and efficiency of the photocuring process, ensure rapid curing and reduce production time, promote uniform cross-linking of materials, improve the adhesion between the coating and the substrate layer, and increase the durability and environmental resistance of the coating.

[0024] In a specific embodiment, the substrate layer is one of PC, PET, PI, PP, PE, TAC, and SRF, and the thickness of the substrate layer is 25-500 um.

[0025] A method for preparing a UV-curable microstructure release film comprises the following steps: S1. Add silicone oligomer, crosslinking agent, anchoring agent, leveling agent, defoaming agent and photoinitiator into a light-proof reactor and stir for 3 hours, and let it stand for defoaming for 2 hours to obtain UV release glue; S2, providing a microstructure coating roller and a substrate layer, adding the UV release glue into the coating tank of the microstructure coating roller, and using the microstructure coating roller to coat the UV release glue on the substrate layer; S3, using UV radiation to cure the UV release glue to form a release coating, and after curing, obtaining the UV-curable microstructure release film.

[0026] By adopting the above technical scheme, the preparation method of the release film includes formula design and microstructure coating roller coating process, combined with UV radiation curing technology, to achieve efficient, uniform and high-quality release film production, and the release coating made of materials such as silicone oligomers, cross-linking agents, anchoring agents, etc. has excellent release performance, surface flatness and chemical stability; the microstructure coating roller can ensure the uniform coating of glue on the substrate layer, and finely control the thickness of the film layer to ensure the stability of the film layer quality, so that the release film has excellent release performance, surface quality, environmental resistance and stability, while improving production efficiency and controllability; UV curing technology not only accelerates the curing process and improves production efficiency, but also meets environmental protection requirements and avoids the energy consumption and environmental burden brought by traditional high-temperature curing.

[0027] In a specific possible implementation manner, the microstructure coating roller is a coating roller having a concave microlens structure, the diameter of the concave microlens structure is 1-200 um, and the ratio of the diameter to the height of the concave microlens structure is 2:1-100:1.

[0028] In a specific embodiment, the coating speed of the microstructure coating roller is 10-200 m / min.

[0029] In a specific embodiment, the UV radiation energy is 50-4000 mj / cm 2 .

[0030] In summary, the beneficial technical effects of the present application are as follows: the UV-curable microstructured release film of the present application can not only provide excellent use effects in the high-performance field, but also meet the market's diverse demands for film materials by improving production efficiency, quality and stability of the film; Through rationally designed components and reasonable proportions, the release force, anti-adhesion, residual adhesion rate, surface quality and durability of the release film are fully optimized; specifically, the highly efficient anti-adhesion properties of the silicone oligomer ensure that the film and the adhesive layer can be easily separated, avoiding residues or surface damage to the adhesive layer during peeling, thus ensuring a good release effect. The use of cross-linking agents enhances the cross-linking and curing degree of the release coating, significantly improving the wear resistance of the release coating, so that it can maintain long-term stable performance in complex and demanding applications; The reasonable ratio of leveling agent and defoamer improves the surface quality of the film, reduces defects such as bubbles and brush marks, and makes the film surface smoother and more uniform, which not only improves the visual effect of the film, but also enhances the physical properties of the film, further meeting the high standard requirements for surface finish; the addition of photoinitiator greatly shortens the curing time of the release coating, accelerates the production process, and adapts to the needs of modern high-speed production lines. At the same time, it ensures that the UV release glue is uniformly cross-linked during the curing process, thereby improving the adhesion of the release coating; the synergistic effect of the anchoring agent and the cross-linking agent improves the weather resistance, high temperature resistance and chemical stability of the release coating, ensuring that the release film can maintain excellent performance during long-term use, avoiding the influence of environmental factors such as ultraviolet rays, humidity or temperature changes on the film, and extending the service life of the release film; In addition, the special microstructure design makes the microstructure release film have a more stable low release force and high residual bonding rate. At the same time, the microstructure release film has good exhaust performance that flat release film products do not have, which meets the application of microstructure release film products in some high requirements and special fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the UV-curable microstructure release film according to an embodiment of the present application.

[0032] Figure 2 This is a schematic diagram of the structure of a release coating used to demonstrate a prism structure with an R angle.

[0033] Figure 3 It is a schematic diagram of the structure of the release coating used to demonstrate the triangular prism structure.

[0034] Figure 4It is a schematic diagram of the structure of the release coating used to demonstrate the trapezoidal prism structure.

[0035] Figure 5 It is a schematic diagram for showing the structure of a microstructured release coating with irregular jitter arrangement.

[0036] Figure 6 It is a schematic diagram for showing the structure of UV-curable planar structure release film.

[0037] Explanation of reference numerals: 1. substrate layer; 2. release coating; 21. microstructure release coating; 22. planar release coating. DETAILED DESCRIPTION

[0038] The following is combined with Figure 1 This application is described in further detail.

[0039] Reference Figure 1 , the embodiment of the present application discloses a UV-curable microstructure release film. In this embodiment, the UV-curable microstructure release film includes but is not limited to being applicable to fields requiring high performance, excellent release properties and surface quality, such as optical films, protective films for electronic products, and other industrial applications requiring release; The UV-curable microstructure release film includes a two-layer structure, a substrate layer 1 and a release coating 2. In this embodiment, the release coating 2 is a microstructure release coating 21. The diameter of the microstructure of the microstructure release coating 21 is 1-200 μm, the ratio of the diameter to the height is 2:1-100:1, and the microstructure is a microlens structure (refer to Figure 1 ); In this embodiment, the microstructure type is not limited to the current microlens structure, but can also be a prism structure with an R angle (see Figure 2 ), triangular prism structure (refer to Figure 3 ), trapezoidal prism structure (refer to Figure 4 ); The top of the R-angle prism structure has a rounded corner (R angle) to reduce sharp edges, reduce stress concentration during peeling, make the release process smoother, improve the flexibility of the release film, and avoid coating cracking caused by stress concentration; the triangular prism has sharp edges and a symmetrical shape, providing uniform release force and a high residual bonding rate, which is suitable for high-precision release films and can achieve stable peeling performance; the trapezoidal prism structure is a strip prism structure with a trapezoidal cross-section, with different widths at the top and bottom, providing higher mechanical strength and stability, improving exhaust performance, and reducing bubble residue; The microstructure can be arranged in a regular manner, or in an irregular shaking (fluctuating) arrangement with varying heights (see Figure 5), the irregular jitter arrangement can increase the surface roughness, improve the exhaust performance, reduce bubble residue, disperse the light, reduce optical interference, and is suitable for optical release films; in practical applications, the appropriate microstructure type is selected according to specific needs, and is optimized in combination with the coating formula and process parameters to achieve high performance and multifunctionality of the release film.

[0040] The material of the substrate layer 1 is polycarbonate film (PC), polyethylene terephthalate film (PET), polyimide film (PI), polypropylene film (PP), polyethylene film (PE), triacetyl cellulose film (TAC) or other suitable film materials. In this embodiment, the material of the substrate layer 1 is preferably polyethylene terephthalate film (PET); The thickness of the substrate layer 1 ranges from 25 to 500 μm. In this embodiment, the thickness of the substrate layer 1 can be flexibly adjusted according to application requirements. Preferably, the thickness of the substrate layer 1 is 50 μm to ensure that the film material has sufficient mechanical strength to withstand the physical stress during processing and maintain the flexibility of the film material, providing a basis for the adhesion of the release coating 2. In this embodiment, the release coating 2 is applied on the substrate layer 1 through a microstructure coating process to form a microstructure release coating 21. The microstructure release coating 21 has a stable low release force and a higher residual adhesion rate. The release coating 2 is an important component of the UV-curable microstructure release film, and its main function is to ensure the release of the film and to easily separate it from the attached adhesive layer. In this embodiment, the main components of the release coating 2 include (by weight): 60-80 parts of organic silicon oligomer, as the main component of release coating 2, provides excellent anti-adhesion property and ensures the release effect of release film; 10-20 parts of the cross-linking agent can enhance the wear resistance of the release coating 2 and improve the durability of the release film; 5-10 parts of anchoring agent can ensure strong adhesion between the release coating 2 and the substrate layer 1, and prevent the release coating 2 from falling off the substrate layer 1; 1-3 parts of leveling agent can improve the surface appearance of the release coating 2 on the substrate layer 1, reduce surface defects such as bubbles, brush marks, etc., and ensure a flat and smooth surface; 1-3 parts of defoaming agent can remove or inhibit the foam formed in the release coating 2, prevent the foam from causing coating defects, and improve the surface quality of the film; 2-8 parts of photoinitiator can promote the rapid curing of the release coating 2, shorten the production cycle and improve production efficiency; This UV-curable microstructure release film has a stable low release force and high residual bonding rate through reasonable component and ratio design and special microstructure design, while improving the mechanical strength, durability and surface quality of the film. Its rapid curing characteristics and advantages in improving production efficiency make this film widely applicable in applications with high performance requirements, and can improve the product's performance and production benefits.

[0041] In this embodiment, the silicone oligomer is an acrylic modified siloxane oligomer. The acrylic modified siloxane oligomer in this embodiment includes but is not limited to SilcoleaseUVPoly110, SilcoleaseUVPoly 112, and SilcoleaseUVPoly118 from Elkem Silicones of France. The acrylic modified siloxane oligomer of the Silcolease UV Poly series can provide good film-forming properties to ensure that the release coating 2 is evenly covered on the substrate layer 1, and it has excellent flexibility and can adapt to the deformation of the substrate to avoid cracking or falling off of the coating. The acrylic modified siloxane oligomer of the Silcolease UV Poly series can synergize with a crosslinking agent (such as vinyl polysiloxane) and a photoinitiator (such as 184) to form a stable crosslinking network, thereby forming good adhesion with the substrate layer 1 and ensuring the stability of the release coating 2. Moreover, it can be quickly cured under the action of UV radiation and photoinitiators to form a stable crosslinking network, thereby improving the mechanical properties and durability of the release film.

[0042] The molecular structure of the acrylic modified siloxane oligomer contains double bonds. The presence of double bonds can participate in the cross-linking reaction during the curing process to form a stable three-dimensional network structure, thereby improving the mechanical strength of the release coating 2 and reducing the occurrence of adverse problems such as the release coating 2 falling off during the use of the release film, thereby extending the service life.

[0043] In this embodiment, the acrylic modified siloxane oligomer includes a modified siloxane containing double bonds, and its weight average molecular weight is 5000-20000; the double bonds in the molecular structure of the oligomer enable the film surface to obtain good wettability, and at the same time the presence of the silicon oxygen chain ensures excellent anti-adhesion, thereby ensuring a good release effect, and the release film can effectively avoid adhesion to the adhesive layer; and the oligomer can form a relatively stable three-dimensional network structure during the curing process, which greatly improves the mechanical strength of the release coating 2.

[0044] In the present embodiment, the cross-linking agent is vinyl polysiloxane, and the weight average molecular weight of the vinyl polysiloxane is 1000-3000; the molecular chain length of the vinyl polysiloxane with a weight average molecular weight of 1000-3000 is moderate, which can ensure effective cross-linking with the acrylic modified siloxane oligomer, and will not be too long to cause excessive viscosity. The moderate molecular weight helps to form a uniform cross-linking network during the UV curing process and enhance the mechanical properties of the cured release coating 2; the polysiloxane in this molecular weight range has good weather resistance and can maintain stable performance during long-term use.

[0045] The crosslinking agent of vinyl polysiloxane has good UV curing properties and can quickly participate in the crosslinking reaction under UV light, thereby improving production efficiency. The curing process is efficient and uniform, ensuring that the product has stable performance and quality in practical applications. In addition, the above crosslinking agent has good transparency and can maintain high transparency after curing, making it suitable for applications such as transparent films or transparent coatings, ensuring that the appearance of the product is not affected. It can also remain stable in the environment, reduce aging, yellowing or degradation caused by ultraviolet rays, and thus extend the service life of the film material.

[0046] In this embodiment, the vinyl polysiloxane includes but is not limited to Dow Corning® UV 9300 and Dow Corning® UV 9400 of the Dow Corning series of the United States; the vinyl polysiloxane molecule contains vinyl (-CH=CH2) groups, which can undergo free radical polymerization under the action of UV radiation and photoinitiators. Under UV radiation, the photoinitiator (such as 184) absorbs light energy and decomposes to produce free radicals, which attack the vinyl double bonds in the vinyl polysiloxane, triggering a chain reaction and ultimately forming a three-dimensional cross-linked network; Dow Corning® UV 9300 is a highly reactive vinyl polysiloxane, which can rapidly undergo free radical polymerization under the action of UV radiation and photoinitiators to form a stable cross-linked structure; Dow Corning® UV 9400 has a higher vinyl content and a faster cross-linking speed, and it can also directly participate in free radical polymerization under the action of a photoinitiator.

[0047] The anchoring agent is one or more of a siloxane anchoring agent, a polyurethane anchoring agent, an acrylic anchoring agent, and an epoxy resin anchoring agent; in this embodiment, preferably, the anchoring agent is a siloxane anchoring agent, and the siloxane anchoring agent is preferably γ-methacryloxypropyltrimethoxysilane; The siloxane anchoring agent undergoes a cross-linking reaction with the surface of the substrate layer 1 through a covalent bond to form a strong anchoring interface, thereby improving the bonding strength between the release coating 2 and the substrate layer 1; the siloxane anchoring agent can effectively improve the bonding force between the release coating 2 and the substrate layer 1, and the siloxane anchoring agent can maintain stable performance in a high temperature, high humidity or chemical environment, so that the release coating 2 is not easy to fall off in a harsh environment; it avoids the poor performance of the microstructured release film due to environmental changes, and prolongs the service life of the release film; γ-Methacryloxypropyltrimethoxysilane has excellent adaptability and can be effectively anchored on a variety of substrate layers 1, and can effectively improve the adhesion performance of the release coating 2 on the PET substrate layer 1. Through the chemical reaction between the siloxane group and the surface of the substrate layer 1, the cross-linked network structure formed further improves the adhesion of the release coating 2 on the PET substrate layer 1, thereby extending the service life of the UV microstructure release film.

[0048] The leveling agent is one or more of an organic silicon leveling agent, a polyurethane leveling agent, an acrylic leveling agent, and a polyester leveling agent; in this embodiment, preferably, the leveling agent is an organic silicon leveling agent, and the organic silicon leveling agent is preferably BYKUV-3500; The silicone leveling agent can reduce the surface tension of the coating, improve the flatness of the coating, reduce defects on the coating surface such as brush marks, bubbles, and sagging, and can help the coating spread evenly during the coating process to ensure a smooth surface of the release coating 2; and the silicone leveling agent has the function of improving the fluidity of the coating, and can enhance the self-leveling property of the release coating 2, so that the coating can spread naturally after application and achieve a uniform and smooth effect; BYK UV-3500, as a silicone leveling agent, can effectively improve the leveling of the coating, reduce bubbles on the coating surface, and improve the surface quality of the release coating 2. By optimizing the leveling process, the coating forms a uniform film during application, avoiding problems such as uneven coating thickness.

[0049] The defoamer is one or more of an organosilicon defoamer, a polyether defoamer, an olefin defoamer, and an alcohol defoamer. In this embodiment, preferably, the defoamer is an organosilicon defoamer, and the organosilicon defoamer is preferably BYK 1799. The use of silicone defoamers can effectively avoid bubbles, holes or unevenness caused by foam, ensure that the surface of the release coating 2 is flat and smooth, and in the process, by controlling the generation of foam, the defoamer can also improve the storage stability of the coating or adhesive and extend the service life of the product; BYK 1799's silicone defoamer can quickly destroy existing foam and effectively prevent the generation of new foam. It reduces the surface tension of the foam and quickly destroys the stable structure of the foam, thereby improving the production efficiency of the coating or adhesive.

[0050] The photoinitiator is one or more of 184, 1173, 819, 907, 651, 379, 369, TPO, 261, 250, 432, and 1176; in this embodiment, preferably, the photoinitiator is 184; Photoinitiators (such as 184) can be rapidly excited and generate free radicals under ultraviolet or visible light irradiation, and can activate the reaction in a short time, ensuring that the release coating 2 is quickly cured, thereby greatly reducing the production cycle; the efficient excitation ability of the photoinitiator improves the efficiency of the photocuring reaction, ensuring that the curing process can be carried out quickly and evenly, thereby improving the overall production efficiency; and, by initiating the photocuring reaction, the photoinitiator promotes the cross-linking between the molecules of the release coating 2, thereby improving the strength and adhesion of the release coating 2, and enhancing the bonding between the release coating 2 and the substrate layer 1, thereby avoiding shedding or peeling; in addition, the resistance of the release coating 2 to environmental factors is also improved, and the use of photoinitiators can improve the durability of the coating in harsh environments.

[0051] The UV-curable microstructure release film in this embodiment has a stable low release force and a high residual adhesion rate through carefully designed components and reasonable ratios and its special microstructure design, so that the microstructure release film achieves an excellent balance in release properties, anti-adhesion, mechanical strength, surface quality, durability, low release force and high residual adhesion rate, exhaust properties, etc. The main technical advantages of the UV-curable microstructure release film are reflected in the following aspects: Highly efficient release performance: Through the excellent anti-adhesion properties of silicone oligomers, the release coating 2 can be easily separated from the surface of the adhesive layer during use without leaving residue or damaging the surface of the adhesive layer, thus ensuring the release effect of the film; Enhanced mechanical properties: The addition of cross-linking agent improves the wear resistance of the release coating 2, making the film adaptable to various applications and maintaining long-term stable performance; Optimization of surface quality: The reasonable ratio of leveling agent and defoamer effectively improves the surface quality of release coating 2, reduces defects such as bubbles and brush marks, ensures that the film surface is smooth and uniform, and provides higher visual and physical quality for the application of the film; Fast curing and efficient production: The use of photoinitiators greatly shortens the curing time of the release coating 2, improves production efficiency, and ensures that the film material completes cross-linking in a short time, meeting the needs of modern high-speed production lines; Stable durability: The synergistic effect of the anchoring agent and the cross-linking agent enhances the weather resistance and temperature resistance of the release coating 2, so that the release coating 2 maintains stable performance during long-term use, avoids performance degradation caused by environmental factors, and extends the service life of the film; Stable low release force and high residual bonding rate: The special microstructure design makes the unit contact area between the release coating of the microstructure release film and the laminated layer smaller, so that it has a more stable low release force and high residual bonding rate than the flat structure release film.

[0052] Good exhaust performance: The special microstructure design allows more exhaust channels between the microstructured release coating 2 and the adhesive layer to be laminated, which can exhaust air more quickly after lamination and avoid bubbles caused by lamination.

[0053] The UV-curable microstructured release film of the present application has achieved improvements in release properties, anti-adhesion, mechanical strength, durability, surface quality, low release force, high residual bonding rate, and exhaust properties, ensuring that the release film has a wide range of applicability in applications with high performance requirements. The rapid curing characteristics of the release coating 2 not only shorten the production cycle, but also improve production efficiency, greatly improving the product's performance and production benefits; in addition, the release film has good transparency, abrasion resistance and weather resistance, can maintain stable performance in a variety of harsh environments, and extend the service life of the film; the release film of the present application can be used in the fields of optical films, electronic product protective films, and other industrial applications requiring high-performance films.

[0054] The present application also provides a method for preparing a UV-curable microstructure release film, including but not limited to preparing the above-mentioned UV-curable microstructure release film, (the specific structure of the UV-curable microstructure release film can be referred to Figure 1 ) The preparation method comprises the following steps: S1. Add silicone oligomer, crosslinking agent, anchoring agent, leveling agent, defoaming agent and photoinitiator into a light-proof reactor and stir for 3 hours, and let it stand for defoaming for 2 hours to obtain UV release glue.

[0055] In this embodiment, the materials and proportions of the organosilicon compound, the crosslinking agent, the anchoring agent, the leveling agent, the defoaming agent, and the photoinitiator can be selected according to those disclosed in the above-mentioned UV-curable microstructure release film, or selected from others; Among them, by weight, 60-80 parts of organosilicon oligomer, 10-20 parts of crosslinking agent, 5-10 parts of anchoring agent, 1-3 parts of leveling agent, 1-3 parts of defoaming agent, and 2-8 parts of photoinitiator; In this embodiment, preferably, the organosilicon oligomer is preferably an acrylic modified siloxane oligomer, the cross-linking agent is preferably vinyl polysiloxane, the anchoring agent is preferably γ-methacryloxypropyltrimethoxysilane, the leveling agent is preferably BYK UV3500, the defoaming agent is preferably BYK 1799, and the photoinitiator is preferably 184.

[0056] In this embodiment, the optimization of stirring time and defoaming time is the key to ensuring the quality of UV release glue. In addition to the original 3 hours of stirring and 2 hours of standing defoaming, a vacuum degassing step can be added to further eliminate bubbles and improve the stability and uniformity of the release glue. At the same time, controlling the influence of environmental factors such as temperature and humidity on the reaction process can also improve the performance of the final UV release glue.

[0057] S2, providing a microstructure coating roller and a substrate layer 1, adding UV release glue into the coating slot of the microstructure coating roller, and coating the UV release glue on the substrate layer 1 using the microstructure coating roller.

[0058] In this embodiment, the substrate layer 1 can be selected from polyethylene terephthalate film (PET), and other types of substrate layer materials can also be selected, such as polycarbonate film (PC) and polyethylene film (PE), to adapt to different application environments; before coating the UV release glue, the surface of the substrate layer 1 can be treated, such as plasma treatment, corona treatment, and coating treatment, which can effectively improve the adhesion and uniformity of the coating film and further enhance the overall performance of the film.

[0059] In the present embodiment, specifically, the microstructure coating roller is a coating roller having a concave microlens structure, the diameter of the concave microlens structure is 1-200 um, and in the present embodiment, preferably, the diameter of the concave microlens structure is 5 um; the diameter to height ratio of the concave microlens structure is 2:1-100:1, and in the present embodiment, preferably, the diameter to height ratio of the concave microlens structure is 2:1-8:1; The size design of the concave microlens structure is crucial to the performance of the release film. The diameter (1-200um) and height (0.5-100um) of the concave microlens can be adjusted in multiple dimensions. Through the fine design of the concave microlens, the optical performance can be further optimized, the optical uniformity of the film can be improved, and the anti-reflection properties of the film surface can be enhanced to meet the needs of different applications. For example, for some high-precision optical films, the diameter of the concave microlens can be selected in a smaller range (such as 1-3um) to improve the optical properties of the film layer.

[0060] The coating speed of the microstructure coating roller is 10-200m / min. In this embodiment, preferably, the coating speed of the microstructure coating roller is 40m / min. The coating speed of the microstructure coating roller is crucial to the thickness control of the film. Within the coating speed range of 10-200m / min, the coating speed can be adjusted according to different production requirements to optimize the uniformity and stability of the film. By finely adjusting the speed, the amount of glue applied can be controlled to avoid uneven film thickness or glue loss due to excessively high coating speed.

[0061] S3, using UV radiation to cure the UV release glue to form a release coating 2, and after curing, a UV-curable microstructure release film is obtained; wherein the UV radiation energy is 50-4000mj / cm 2 In this embodiment, preferably, the UV radiation energy is 1200 mj / cm 2 .

[0062] In this embodiment, during the UV radiation process, precise control of energy is the key to ensuring uniformity of film curing and film performance. According to different release film formulations, UV light sources of different wavelengths (such as UV-A, UV-B, UV-C) can be selected to achieve the best curing effect. For example, for a glue formulation with a high degree of polymer crosslinking, a higher energy UV radiation (such as 1200mJ / cm 2 ), to accelerate the curing process of the release coating 2 and improve the strength and stability of the release coating 2; In terms of UV radiation equipment, multi-lamp radiation sources, circular UV curing systems, etc. can be used to ensure that the radiation evenly covers the entire film surface; in addition, the working temperature, humidity and radiation time of the curing equipment should also be carefully controlled to ensure the stability of the curing effect and avoid fluctuations in film performance due to temperature fluctuations; The performance of the cured release film can also be improved through post-processing processes, such as cooling, hot pressing, release treatment, etc., to further improve the surface smoothness, weather resistance and compressive strength of the film.

[0063] In order to verify the technical effect of the present application, multiple embodiments are designed, and comparative experiments are carried out with traditional planar structure release films. By comparing the effects of release coatings 2 with different structures, coating conditions and formula components on the performance of the release films, the advantages of the microstructured release films in terms of performance are verified. The specific embodiments and comparative examples are designed, as well as the experimental technical effects are described as follows: In this embodiment, 8 groups of embodiments are designed below. Embodiments 1-8 are a UV-curable microstructure release film, wherein the release coating 2 in the embodiment is a microstructure release coating 21. For specific structures, please refer to Figure 1 shown.

[0064] The weight proportions of the raw materials and components of Example 1 are shown in Table 1.

[0065] Table 1 In Example 1, the above components are added in parts by weight in sequence into a light-proof reaction kettle, stirred in a light-proof manner for 3 hours, and then allowed to stand for defoaming for 2 hours to obtain UV release glue. The UV release glue is added into a coating glue tank, and a microstructure coating roller is used to coat the UV release glue on the PET substrate layer 1 to form a microstructure release coating. After UV radiation curing, a UV-curable microstructure release film product is obtained. The microstructure coating roller is a concave microlens structure, and the diameter of the concave microlens structure is 1 um (that is, the diameter of the microstructure on the formed microstructure release coating 21 is 1 um, and the formed microstructure is a convex microlens structure), and the diameter-to-height ratio is 2:1; the coating vehicle speed is 40 m / min; the UV radiation energy is 1200 mj / cm 2 .

[0066] Example 2: Compared with Example 1, the difference is that the diameter of the concave microlens structure of the microstructure coating roller is 3um, and the other conditions are the same.

[0067] Example 3: Compared with Example 1, the difference is that the diameter of the concave microlens structure of the microstructure coating roller is 5 um, and the other conditions are the same.

[0068] Example 4: Compared with Example 1, the difference is that the diameter of the concave microlens structure of the microstructure coating roller is 10 um, and the other conditions are the same.

[0069] Example 5: Compared with Example 1, the difference is that the diameter of the concave microlens structure of the microstructure coating roller is 5 um, and the ratio of diameter to height is 3:1.

[0070] Example 6: Similar to Example 5, except that the diameter of the concave microlens structure of the microstructure coating roller is 5 um, and the ratio of diameter to height is 4:1.

[0071] Compared with Example 1, Example 7 has different raw materials and weight proportions of each component. The weight proportions of the raw materials and each component of Example 7 are shown in Table 2. Compared with Example 1, Example 7 also has the following differences: the diameter of the concave microlens structure of the microstructure coating roller is 5um, and the ratio of diameter to height is 4:1.

[0072] Table 2 Example 8: Compared with Example 1, the difference is that the diameter of the concave microlens structure of the microstructure coating roller is 10 um, and the ratio of diameter to height is 4:1.

[0073] In this embodiment, 3 groups of comparative examples are designed below. The comparative example is a UV-curable planar structure release film, wherein the release coating 2 in the comparative example is a planar release coating 22. For specific structures, please refer to Figure 6 shown.

[0074] The weight proportions of the raw materials and components of Comparative Example 1 are shown in Table 3.

[0075] Table 3 In comparative example 1, a mirror coating roller without microstructure is used to coat UV release glue on the PET substrate layer 1 to form a planar release coating 22, and a UV-curable planar structure release film is obtained after UV radiation curing. The coating and curing conditions are the same as those in Example 1, and the thickness of the planar release coating 22 is 2.5 um.

[0076] Comparative Example 2: Compared with Comparative Example 1, the difference is that the thickness of the planar release coating 22 is 5 um, and the other conditions are the same.

[0077] Compared with Example 1, Example 3 has different raw materials and weight fractions of each component. The weight fractions of the raw materials and each component of Example 3 are shown in Table 4. Compared with Example 1, Example 3 also has the following differences: the thickness of the planar release coating 22 is 5 um.

[0078] Table 4 The following tests were conducted on Examples 1-8 and Comparative Examples 1-3, including 20-min room temperature release force test, 24-h room temperature release force test, 20-h aging release force test, residual adhesion rate test, and exhaust performance test. Please refer to Table 5 for specific test results.

[0079] Table 5 Note: 1.20min release force at room temperature is obtained by sticking TESA 7475 tape on the release surface of the release film for 20min, and the test method is ASTM D3330; 2.24h room temperature release force is obtained by sticking TESA 7475 tape on the release surface of the release film for 24 hours, and the test method is ASTM D3330; 3. The aging release force is obtained by sticking TESA 7475 tape on the release surface of the release film, under the conditions of 2Kg pressure, 70℃ and 20h, and the test method is ASTM D3330; 4. The residual adhesion rate is tested using NITTO 31B tape, and the test method is ASTM D3330; 5. The above four test values ​​are the average of five test values; 6. The exhaust test is to stick the release film and 3M 4920 tape into a size of 40cm*40cm, then stick them together and visually judge the time required for completely no air bubbles.

[0080] By comparing and analyzing Examples 1-8 with Comparative Examples 1-3, the following conclusions can be drawn: 1.Performance advantages of UV-curable microstructured release films Size-to-height ratio of the microlens structure: When the microlens diameter is 5um and the ratio of the microlens height to the diameter is between 2:1 and 4:1, the microstructure release film exhibits ultra-low release force and high residual adhesion rate; this indicates that a moderate microlens size-to-height ratio can effectively reduce the release force while improving the residual adhesion rate and air venting, achieving a better release effect.

[0081] The impact of a larger diameter (10um) of the microlens structure: When the diameter of the microlens increases to 10um, the release force does not decrease significantly despite the larger amount of release glue required for the release surface. This indicates that a larger microlens size does not significantly improve release performance, but may increase the amount of UV release glue used, leading to an increase in production costs. Therefore, the optimal size of the microlens should be controlled at around 5um to achieve a better release effect.

[0082] Effect of smaller diameter of microlens structure: When the diameter of the microlens structure is too small, the contact surface per unit area increases, resulting in an increase in release force and a decrease in residual adhesion rate; this indicates that an overly small microlens structure may lead to unfavorable release performance, especially at an ultra-small diameter, which will increase the contact between the release surface and the adhered layer, increase the release force and reduce the residual adhesion rate.

[0083] 2.Performance issues of UV-curable planar structure release films High release force of the flat release coating 22: Comparative Examples 1-3 are all flat coatings without microstructures, which results in a larger bonding area between the surface of the flat release coating 22 and the adhered layer. Therefore, the release force of the UV-cured flat structure release film at room temperature for 20 minutes and 24 hours is higher, and the aging release force is also larger; this indicates that the release performance of the UV-cured flat structure release film is poor, and as the use time increases, the release force tends to increase, making it difficult to maintain stable performance.

[0084] Low residual bonding rate: Since the flat release film has no microstructure and the unit contact area is large, its residual bonding rate is low; in contrast, the microstructured release film effectively reduces the contact area through the microlens structure, improves the release performance, and reduces the residual adhesion.

[0085] Poor exhaust performance: Since the UV flat structure release film has no microstructure design, there are fewer exhaust channels, which makes it difficult to remove bubbles between the adhesive layer after bonding or takes a long time to remove them.

[0086] In order to further verify the technical effect of the present application and the influence of the cross-linking agent on the release force and residual adhesion rate of the release film of the present application, Examples 9-16 and Comparative Examples 4-7 are designed, focusing on the influence of the amount of the cross-linking agent (vinyl polysiloxane) on the release force and residual adhesion rate. By adjusting the amount of the cross-linking agent, it is demonstrated how the amount of the cross-linking agent (10-20 parts) of the present application improves the release force and residual adhesion rate, and the comparative examples are used to compare the performance changes when the cross-linking agent is insufficient or excessive.

[0087] Example 9: The weight proportions of the raw materials and each component are shown in Table 6.

[0088] Table 6 Example 10: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 12 parts; Example 11: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 14 parts; Example 12: Compared with Example 9, the difference is that the amount of the crosslinking agent (vinyl polysiloxane) is 15 parts; Example 13: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 16 parts; Example 14: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 18 parts; Example 15: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 20 parts; Example 16: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 22 parts; Comparative Example 4: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 5 parts; Comparative Example 5: Compared with Example 9, the difference is that the number of parts of the crosslinking agent (vinyl polysiloxane) is 8 parts; Comparative Example 6: Compared with Example 9, the difference is that the amount of the crosslinking agent (vinyl polysiloxane) is 25 parts; Comparative Example 7: Compared with Example 9, the difference is that the amount of the crosslinking agent (vinyl polysiloxane) is 30 parts; The following tests were conducted on Examples 9-16 and Comparative Examples 4-7, and the test items included 20-min room temperature release force, 24-h room temperature release force, 20-h aging release force, residual bonding rate, and exhaust performance. Please refer to Table 7 for specific test results.

[0089] Test results analysis 1. Release force analysis 20min release force at room temperature: With the increase of the amount of cross-linking agent, the release force gradually decreases; Examples 9-15 (10-20 parts of cross-linking agent) show lower release force, indicating that a moderate amount of cross-linking agent can improve the release effect; Comparative Example 4 (5 parts) and Comparative Example 5 (8 parts) have higher release forces, indicating that when the cross-linking agent is insufficient, the release effect is poor.

[0090] 24h release force at room temperature: The release force of Examples 9-15 (10-20 parts of cross-linking agent) at room temperature for 24h is still relatively low, indicating that a moderate amount of cross-linking agent can maintain long-term stability; the release force of Comparative Example 4 (6.5gf / in) and Comparative Example 5 (5.5gf / in) is relatively high, indicating that when the cross-linking agent is insufficient, the long-term stability is poor.

[0091] 20h aging release force: The release force of Examples 9-15 (10-20 parts of cross-linking agent) under aging conditions is still relatively low, indicating that a moderate amount of cross-linking agent can improve the aging stability; the release force of Comparative Example 4 (7.0 gf / in) and Comparative Example 5 (6.0 gf / in) is relatively high, indicating that when the cross-linking agent is insufficient, the aging stability is poor.

[0092] 2. Residual bonding rate analysis As the amount of cross-linking agent increases, the residual bonding rate gradually increases; Examples 9-15 (10-20 parts of cross-linking agent) show higher residual bonding rates, indicating that a moderate amount of cross-linking agent can significantly improve the bonding strength between the coating and the substrate; Comparative Examples 4 (75.0%) and Comparative Example 5 (78.0%) have lower residual bonding rates, indicating that when the cross-linking agent is insufficient, the bonding strength is poor.

[0093] 3. Exhaust performance analysis As the amount of cross-linking agent increases, the exhaust performance gradually improves; Examples 9-15 (10-20 parts of cross-linking agent) show good exhaust performance, indicating that a moderate amount of cross-linking agent can improve the exhaust effect; Comparative Example 4 (10 seconds) and Comparative Example 5 (8 seconds) have poor exhaust performance, indicating that when the cross-linking agent is insufficient, the exhaust effect is poor.

[0094] 4. Cross-linker Excess Analysis Comparative Example 6 (25 parts) and Comparative Example 7 (30 parts) exhibited extremely low release forces (1.5 gf / in and 1.2 gf / in) and extremely high residual adhesion rates (95.0% and 96.0%), but resulted in increased brittleness of the coatings, which were not suitable for practical applications.

[0095] in conclusion: 1. A moderate amount of cross-linking agent (10-20 parts) can significantly improve the release force, residual adhesion rate and exhaust performance; the release force and residual adhesion rate are balanced, which is suitable as the preferred formula.

[0096] 2. Effect of insufficient cross-linking agent: Comparative Example 4 (5 parts) and Comparative Example 5 (8 parts) have higher release forces, and poorer residual adhesion and degassing performance, indicating that when the cross-linking agent is insufficient, the coating performance is significantly reduced.

[0097] 3. Effect of excessive cross-linking agent: The release force of Comparative Example 6 (25 parts) and Comparative Example 7 (30 parts) is extremely low, and the residual bonding rate is extremely high, but it will increase the brittleness of the coating, so it should be used with caution in practical applications.

[0098] 4. Best embodiment: Embodiment 12: 15 parts of cross-linking agent, release force 2.8 gf / in, residual bonding rate 90.0%, exhaust performance 3.5 seconds; Embodiment 13: 16 parts of cross-linking agent, release force 2.5 gf / in, residual bonding rate 91.5%, exhaust performance 3 seconds; Embodiment 14: 18 parts of cross-linking agent, release force 2.2 gf / in, residual bonding rate 92.0%, exhaust performance 2.8 seconds.

[0099] In actual production, a formula with a cross-linking agent dosage of 10-20 parts is preferably used to obtain the best comprehensive performance; a moderate amount of cross-linking agent (10-20 parts) can significantly improve the comprehensive performance of UV-curable microstructure release film, including reducing release force, improving residual adhesion rate, optimizing exhaust performance and enhancing aging stability, thereby ensuring that the release film has excellent peeling effect, bonding force, production efficiency and durability in practical applications, while avoiding performance degradation or coating brittleness problems caused by insufficient or excessive cross-linking agent, providing reliable technical support for the high performance and wide application of release film; for special application scenarios, the amount of cross-linking agent can be adjusted according to specific needs to further optimize performance.

[0100] The UV-curable microstructured release film of the present application realizes efficient, uniform and high-quality release film production through optimized formula design and microstructured coating roller coating process, combined with UV radiation curing technology. The release coating 2 made of materials such as silicone oligomers, cross-linking agents, and anchoring agents has excellent release performance, surface flatness and chemical stability; the microstructured coating roller can ensure the uniform coating of UV release glue on the substrate layer 1, and finely control the thickness of the microstructured release coating 21 to ensure the stable quality of the microstructured release coating 21, so that the UV-curable microstructured release film has excellent release performance, surface quality, environmental resistance and stability, as well as ultra-low release force and high residual bonding rate, while improving production efficiency and controllability; UV curing technology not only accelerates the curing process and improves production efficiency, but also meets environmental protection requirements and avoids the energy consumption and environmental burden brought by traditional high-temperature curing.

[0101] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A UV-curable microstructure release film, characterized in that: It comprises a substrate layer and a release coating layer disposed on the substrate layer; In terms of weight, the materials of the release coating include: 60-80 parts of silicone oligomer, 10-20 parts of cross-linking agent, 5-10 parts of anchoring agent, 1-3 parts of leveling agent, 1-3 parts of defoaming agent, and 2-8 parts of photoinitiator; the release coating is a microstructure release coating, the diameter of the microstructure of the microstructure release coating is 1-200um, the ratio of diameter to height is 2:1-100:1, and the microstructure is a microlens structure.

2. The UV-curable microstructure release film according to claim 1, characterized in that: The organosilicon oligomer is an acrylic acid-modified siloxane oligomer.

3. The UV-curable microstructure release film according to claim 2, characterized in that: The acrylic modified siloxane oligomer comprises modified siloxane containing double bonds, and has a weight average molecular weight of 5,000-20,000.

4. The UV-curable microstructure release film according to claim 1, characterized in that: The crosslinking agent is vinyl polysiloxane.

5. The UV-curable microstructure release film according to claim 4, characterized in that: The weight average molecular weight of the vinyl polysiloxane is 1000-3000.

6. The UV-curable microstructure release film according to claim 1, characterized in that: The anchoring agent is one or more of a siloxane anchoring agent, a polyurethane anchoring agent, an acrylic anchoring agent, and an epoxy resin anchoring agent.

7. The UV-curable microstructure release film according to claim 1, characterized in that: The leveling agent is one or more of an organic silicon leveling agent, a polyurethane leveling agent, an acrylic leveling agent, and a polyester leveling agent.

8. The UV-curable microstructure release film according to claim 1, characterized in that: The defoaming agent is one or more of an organosilicon defoaming agent, a polyether defoaming agent, an olefin defoaming agent, and an alcohol defoaming agent.

9. The UV-curable microstructure release film according to claim 1, characterized in that: The photoinitiator is one or more of 184, 1173, 819, 907, 651, 379, 369, TPO, 261, 250, 432, and 1176.

10. The UV-curable microstructure release film according to claim 1, characterized in that: The substrate layer is one of PC, PET, PI, PP, PE, TAC, and SRF, and the thickness of the substrate layer is 25-500um.

11. A method for preparing the UV-curable microstructure release film according to any one of claims 1 to 10, characterized in that: The following steps are involved: S1. Add silicone oligomer, crosslinking agent, anchoring agent, leveling agent, defoaming agent and photoinitiator into a light-proof reactor and stir for 3 hours, and let it stand for defoaming for 2 hours to obtain UV release glue; S2. Provide a microstructure coating roller and a substrate layer, add the UV release glue into the coating groove of the microstructure coating roller, and use the microstructure coating roller to coat the UV release glue on the substrate layer; the microstructure coating roller is a coating roller having a concave microlens structure, the diameter of the concave microlens structure is 1-200 um, and the diameter and height ratio of the concave microlens structure is 2:1-100:1; S3, using UV radiation to cure the UV release glue to form a release coating, and after curing, obtaining the UV-curable microstructure release film.

12. The preparation method according to claim 11, characterized in that: The coating speed of the microstructure coating roller is 10-200 m / min.

13. The preparation method according to claim 11, characterized in that: The UV radiation energy is 50-4000mj / cm 2 .

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