A Fresnel lens texture UV transfer process

Abstract

This application relates to the technical field of transfer printing, specifically to a Fresnel lens texture UV transfer printing process, which includes the following steps: mold opening – coating with UV transfer adhesive – rolling and degassing – pre-curing treatment – ​​UV curing – demolding; wherein, the UV transfer adhesive is composed of the following raw materials in parts by weight: 20-35 parts acrylate, 30-50 parts modified epoxy acrylate, 15-25 parts reactive diluent, 5-15 parts photoinitiator, 1.5-4 parts antioxidant, 1-3 parts adhesion promoter, and 0.05-0.3 parts polymerization inhibitor. The Fresnel lens texture UV transfer printing process of this application, through rolling and degassing and pre-curing treatment, can improve the adhesion between the transfer substrate and the transfer template, making the transfer substrate less prone to falling off; the prepared UV transfer adhesive has good adhesion and flexibility to the transfer substrate, and the cured transfer film is less prone to texture tearing during demolding, improving transfer efficiency and transfer effect.

Description

Technical Field

[0001] This application relates to the technical field of transfer printing, and more specifically, to a Fresnel lens texture UV transfer printing process. Background Technology

[0002] The Fresnel lens texture is formed based on the Fresnel lens and consists of several concentric circles of different sizes. The textures of different depths are formed between adjacent concentric circles. Through the interference of light, people can visually perceive a special texture effect in three dimensions.

[0003] The conventional Fresnel lens texture UV transfer process involves coating a transfer stencil with UV transfer adhesive, then covering the stencil with a transfer substrate. After pressing, the transfer substrate acquires a Fresnel lens texture. The Fresnel lens texture on the transfer substrate is then cured and set, resulting in a transfer film with the Fresnel lens texture. Finally, the transfer film is demolded from the transfer stencil. When applying the transfer film with the Fresnel lens texture, it can be laminated onto materials such as PET, PC, composite boards, PMMA, glass, ceramics, and metals to produce products with the Fresnel lens texture. This process is widely used in the manufacturing of 3D mobile phone cover plates, mobile phone cameras, optical instruments, and other electronic digital products.

[0004] When using conventional UV transfer printing, the transfer template with Fresnel lens texture has multiple concentric circles of different depths on its surface, resulting in a complex surface texture and numerous uneven surfaces. This makes it easy for the transfer substrate to detach from the Fresnel lens texture template during the transfer process, thus reducing the transfer efficiency of the Fresnel lens texture. Summary of the Invention

[0005] To address the problem that the transfer film easily detaches from the transfer template with the Fresnel lens texture during the Fresnel lens texture UV transfer process, this application provides a Fresnel lens texture UV transfer process.

[0006] This application provides a Fresnel lens texture UV transfer printing process, which adopts the following technical solution:

[0007] A Fresnel lens texture UV transfer process includes the following steps:

[0008] S1. Mold making: Select a metal sheet as the base material, and create a Fresnel lens texture in the effective area of ​​the metal sheet to form a Fresnel lens texture template.

[0009] S2. Apply transfer adhesive: Apply UV transfer adhesive evenly to the texture area of ​​the Fresnel lens texture template;

[0010] S3, Rolling and Degassing: The transfer substrate is placed on a Fresnel lens texture template coated with UV transfer adhesive and subjected to uniform rolling and degassing treatment.

[0011] S4. Pre-curing treatment: After S3 rolling and degassing treatment, the transfer substrate and Fresnel lens texture template are left to stand at 30-40℃ for 5-10 minutes.

[0012] S5, UV curing: The transfer substrate that has been pre-cured by S4 is subjected to UV curing treatment with Fresnel lens texture template.

[0013] S6. Demolding: After curing, the transfer substrate is demolded from the Fresnel lens texture template to obtain a transfer film with a Fresnel lens texture.

[0014] By adopting the above technical solution, a Fresnel lens texture to be transferred is formed on a metal sheet. Preferably, the Fresnel lens texture is formed by laser engraving. Compared with other mold-making processes, laser engraving has higher accuracy and precision, and the surface of the resulting texture template is smooth, which helps to improve demolding efficiency and makes the Fresnel lens texture on the transfer substrate less likely to be damaged during demolding. By uniformly coating the modified UV transfer adhesive onto the Fresnel lens texture template, and then evenly spreading and pressing the transfer substrate, the transfer substrate and the Fresnel lens texture template are stably and tightly adhered to each other, eliminating excess air bubbles and making the transfer substrate less likely to fall off. Finally, the transfer substrate and the Fresnel lens texture template are placed in a 3 The UV transfer adhesive is allowed to stand at 0-40℃ to fully spread and disperse on the substrate surface, improving its adhesion. Then, it is cured with two specific UV light curing energies to stabilize the adhesive and enhance its adhesion stability on the substrate. The substrate is then peeled off the transfer template, completing the Fresnel lens texture transfer and producing a Fresnel lens textured transfer film. This film includes a transfer substrate and an adhesive layer stably attached to its surface. The resulting Fresnel lens textured transfer film can be laminated onto the surface of the desired material to create a product with a wide range of applications.

[0015] Preferably, the UV transfer adhesive used in step S2 is composed of the following raw materials in parts by weight: 20-35 parts acrylate, 30-50 parts modified epoxy acrylate, 15-25 parts reactive diluent, 5-15 parts photoinitiator, 1.5-4 parts antioxidant, 1-3 parts adhesion promoter, and 0.05-0.3 parts polymerization inhibitor.

[0016] By adopting the above technical solution, a UV transfer adhesive with excellent weather resistance, flexibility, and adhesion is formed through a system of acrylate, modified epoxy acrylate, and reactive diluent in an optimal ratio. The combination of modified epoxy acrylate and adhesion promoter enhances the bonding force between the UV transfer adhesive and the transfer substrate, thereby improving the adhesion of the UV transfer adhesive to the transfer substrate. Furthermore, the use of an optimal ratio of polymerization inhibitor and photoinitiator ensures stable cross-linking and curing performance of the UV transfer adhesive during UV curing, further enhancing its adhesion to the transfer substrate and making it less prone to detachment during transfer. Moreover, it facilitates demolding after curing, reducing texture tearing and damage to the Fresnel lens textured transfer film obtained during demolding, thus improving transfer efficiency and transfer effect.

[0017] Preferably, the modified epoxy acrylate is prepared by the following steps:

[0018] A1: Add 20-30 parts of epoxy resin to 10-20 parts of polypropylene glycol diglycidyl ether and dissolve and mix well;

[0019] A2: Add 12-22 parts acrylic acid, 1-3 parts diethylamine and 0.5-1.5 parts diethylenetriamine, heat to 86-100℃ and react for 5-7 hours to obtain modified epoxy acrylate.

[0020] By adopting the above technical solution, epoxy resin exhibits excellent water resistance, adhesion, and toughness. Furthermore, using polypropylene glycol diglycidyl ether as a co-solvent, diethylamine as a catalyst, and diethylenetriamine as a crosslinking agent promotes the esterification reaction between the epoxy groups of the epoxy resin and the carboxyl groups of acrylic acid. This reaction generates a modified epoxy acrylate with excellent weather resistance, flexibility, and adhesion. The modified epoxy acrylate prepared using this method improves the weather resistance, photochemical activity, flexibility, and adhesion of the UV transfer adhesive, making the transfer film less prone to detachment during transfer. After curing, the transfer film with Fresnel lens texture is easy to demold.

[0021] Preferably, the reactive diluent is composed of tritetrapropylene glycol diacrylate and trimethylolpropane triacrylate in a weight ratio of 1:(0.5-0.8).

[0022] By adopting the above technical solution and using a specific ratio of reactive diluent, the activity and viscosity of the UV transfer adhesive system are made moderate, thereby improving the penetration of the UV transfer adhesive and enhancing its extensibility on the transfer substrate.

[0023] When the content of reactive diluent is low, the extensibility of UV transfer adhesive decreases, while when the content of reactive diluent is high, the curing efficiency of UV transfer adhesive system decreases.

[0024] Preferably, the photoinitiator is composed of benzoin dimethyl ether, 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide and diethylamine in a weight ratio of 1:(0.4-0.8):(0.1-0.3).

[0025] By adopting the above technical solution, using a better ratio of photoinitiators, and using diethylamine as a co-initiator, the initiation efficiency of the photoinitiators is improved. This allows the UV transfer adhesive to generate stable free radicals under the action of UV light, which initiate a stable cross-linking reaction of the acrylate, epoxy acrylate, and reactive diluent system for curing, thereby improving the curing efficiency.

[0026] When the photoinitiator content is low, the curing efficiency of the UV transfer adhesive is low. When the photoinitiator content is high, the curing efficiency of the UV transfer adhesive is too fast, which can easily make the resulting transfer film brittle and reduce its flexibility.

[0027] Preferably, the antioxidant is composed of thiol-based benzimidazole and p-phenylenediamine in a weight ratio of 1:(0.1-0.3).

[0028] By adopting the above technical solution, the optimal ratio of thiol-based benzimidazole and p-phenylenediamine produces a synergistic effect, which enhances the antioxidant properties of the UV transfer adhesive, making the transfer film with Fresnel lens texture obtained by transfer less prone to aging and yellowing.

[0029] Preferably, the adhesion promoter is polyethylene glycol monomethacrylate phosphate, and the polymerization inhibitor is either p-benzoquinone or hydroquinone.

[0030] By adopting the above technical solution, polyethylene glycol monomethacrylate phosphate helps to increase the polarity of the active groups in the acrylate molecule, enabling the UV transfer adhesive to form a strong bond with the transfer substrate, thereby improving the adhesion of the UV transfer adhesive on the transfer substrate; by using p-benzoquinone or hydroquinone as a polymerization inhibitor, the generation of byproducts during free radical polymerization is reduced, the reaction conversion rate is improved, and thus the flexibility and adhesion properties of the UV transfer adhesive are improved.

[0031] Preferably, the UV transfer adhesive is prepared by the following steps:

[0032] B1: Mix 20-30 parts of acrylate, 30-50 parts of modified epoxy acrylate, 15-25 parts of reactive diluent and 0.05-0.3 parts of polymerization inhibitor, and stir at 25-45℃ to obtain mixture A;

[0033] B2: Add 5-15 parts of photoinitiator, 1.5-4 parts of antioxidant and 1-3 parts of adhesion promoter to mixture A and mix well to obtain UV transfer adhesive.

[0034] By adopting the above technical solution, at a specific temperature, a better ratio of acrylate, modified epoxy acrylate and reactive diluent are subjected to free radical polymerization to form mixture A; then, a photoinitiator, antioxidant and adhesion promoter are added to mixture A to obtain a high-performance UV transfer adhesive that can be stably cured under UV light and forms a good-adhesive and antioxidant adhesive layer on the surface of the transfer film.

[0035] Preferably, the transfer substrate in step S3 is an optical PET sheet, an optical PC sheet, or an optical polyurethane film, and the thickness of the transfer substrate is 0.01-0.1 mm.

[0036] By adopting the above technical solutions, optical PET sheets, optical PC sheets, or optical polyurethane films have excellent optical performance and low cost, and are widely applicable; the optimal size of the transfer substrate makes the transfer film with Fresnel lens texture highly applicable and will not have a significant impact on the size of the product being used.

[0037] Preferably, the photocuring in step S5 is divided into two stages, wherein the photocuring energy in the first stage is 780-980 mJ / cm². 2 The photocuring energy in the second stage is 1150-1250 mJ / cm². 2 .

[0038] By adopting the above technical solution, the UV transfer adhesive is stably cured. First, a lower light curing energy is used for curing, which initially cures the surface layer of the UV transfer adhesive and the transfer substrate, improving the adhesion between the UV transfer adhesive and the transfer substrate, and forming a Fresnel lens texture on the surface of the transfer substrate. Then, a higher light curing energy is used to cure the UV transfer adhesive as a whole, thereby making the Fresnel lens texture stably bonded to the transfer substrate. This improves adhesion and reduces the likelihood of texture tearing or damage to the Fresnel lens texture of the adhesive layer during demolding.

[0039] In summary, this application has the following beneficial effects:

[0040] 1. The Fresnel lens texture UV transfer process of this application, by performing rolling degassing and pre-curing treatment before UV curing, allows the UV transfer adhesive to be fully extended and dispersed on the surface of the transfer substrate. Then, it is subjected to two UV curing treatments with specific curing energy, which improves the bonding force between the UV transfer adhesive and the transfer substrate, thereby improving the adhesion stability of the UV transfer adhesive on the transfer substrate. This makes it less likely for the transfer substrate to fall off the Fresnel lens texture template during transfer, thus improving the transfer efficiency.

[0041] 2. By using modified epoxy acrylate, the weather resistance, flexibility, and adhesion of the UV transfer adhesive system are improved. Then, in synergy with acrylate and reactive diluent, and with the help of polymerization inhibitors, adhesion promoters, and antioxidants, a high-performance, highly flexible, and adhesive UV transfer adhesive is formed. This makes it difficult for the transfer substrate to fall off the Fresnel lens texture template during transfer, and the transfer film obtained after curing is less likely to have texture tearing or damage during demolding. Detailed Implementation

[0042] The present application will be further described in detail below with reference to the embodiments.

[0043] Preparation example of modified epoxy acrylate

[0044] Preparation Example 1

[0045] A modified epoxy acrylate is prepared by the following steps:

[0046] A1: Add 2 kg of epoxy resin to 1 kg of polypropylene glycol diglycidyl ether and dissolve and mix well;

[0047] A2: Add 1.2 kg of acrylic acid, 0.1 kg of diethylamine and 0.05 kg of diethylenetriamine, heat to 86°C and react for 5 h to obtain modified epoxy acrylate.

[0048] Preparation Examples 2-3

[0049] The difference between Preparation Example 2-3 and Preparation Example 1 lies in the amount of reactants and the reaction conditions, as detailed in Table 1 below.

[0050] Table 1. Amounts of reactants and reaction conditions for preparation examples 1-3.

[0051]

[0052] Preparation of Comparative Example 1

[0053] The difference between Comparative Example 1 and Preparation Example 2 is that diethylenetriamine is replaced with diethylamine in equal amounts, while other proportions and reaction conditions are the same.

[0054] Example of UV transfer adhesive preparation

[0055] Preparation Example 4

[0056] A UV transfer adhesive, the preparation of which includes the following steps:

[0057] B1: Mix 2 kg of acrylate, 3 kg of modified epoxy acrylate, 1.5 kg of reactive diluent and 0.005 kg of polymerization inhibitor, stir and mix at 25°C to obtain mixture A;

[0058] B2: Add 0.5 kg of photoinitiator, 0.15 kg of antioxidant and 0.1 kg of adhesion promoter to mixture A and mix well to obtain UV transfer adhesive.

[0059] Preparation Examples 5-6

[0060] The difference between Preparation Examples 5-6 and Preparation Example 4 lies in the amount of reactants and the reaction conditions, as detailed in Table 2 below.

[0061] Table 2 shows the amounts of reactants and reaction conditions used in Preparation Examples 4-6.

[0062]

[0063] Preparation Examples 7-9

[0064] The difference between Preparation Examples 7-9 and Preparation Example 6 lies in the amount and ratio of the raw materials. See Table 3 below for details.

[0065] Table 3. Proportions of raw materials and amounts used in preparation examples 7-9

[0066]

[0067] Preparation Example 10

[0068] The difference between Preparation Example 10 and Preparation Example 9 is that the source of the modified epoxy acrylate is different. Preparation Example 10 uses the modified epoxy acrylate prepared in Comparative Example 1 above, while the other amounts and proportions are the same as in Preparation Example 9.

[0069] Preparation of Comparative Examples 2-4

[0070] The difference between Comparative Examples 2-4 and Example 9 is that the amount of modified epoxy acrylate used in Comparative Example 2 is different, the amount of adhesion promoter used in Comparative Example 3 is different, and the amount and ratio of photoinitiator used in Comparative Example 4 are different. See Table 4 below for details.

[0071] Table 4. Raw materials and quantities used in the preparation of Comparative Examples 2-4

[0072]

[0073]

[0074] Example

[0075] Example 1

[0076] A Fresnel lens texture UV transfer process includes the following steps:

[0077] S1. Mold making: Select a metal sheet as the base material, and create a Fresnel lens texture in the effective area of ​​the metal sheet to form a Fresnel lens texture template.

[0078] S2. Coating the transfer adhesive: The UV transfer adhesive prepared in Preparation Example 4 is uniformly coated onto the textured area of ​​the Fresnel lens texture template.

[0079] S3, Rolling and Degassing: The transfer substrate is placed on a Fresnel lens texture template coated with UV transfer adhesive and subjected to uniform rolling and degassing treatment.

[0080] S4. Pre-curing treatment: The transfer substrate that has been rolled and degassed in S3 is placed with the Fresnel lens texture template at 30°C for 5 minutes.

[0081] S5, UV Curing: The transfer substrate, after S4 pre-curing, is subjected to UV curing treatment with the Fresnel lens texture template. The curing process consists of two stages, with the first stage using a curing energy of 780 mJ / cm². 2 The curing time is 3 seconds, and the curing energy for the second stage is 1150 mJ / cm². 2 The curing time is 12 seconds.

[0082] S6. Demolding: The transfer substrate that has been UV cured in S5 is demolded from the Fresnel lens texture template to obtain a transfer film with a Fresnel lens texture.

[0083] The transfer substrate can be an optical PET film, an optical PC film, or an optical polyurethane film. In this embodiment, an optical PET film is preferred. The thickness of the transfer substrate is 0.01-0.1 mm, and can be 0.01 mm, 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, or 0.1 mm. In this embodiment, the thickness is preferably 0.05 mm.

[0084] Example 2-3

[0085] The difference between Examples 2-3 and Example 1 lies in the UV curing pretreatment parameters, the source of the UV transfer adhesive, and the UV curing parameters. See Table 5 below for details.

[0086] Table 5. Curing Pretreatment Parameters, UV Transfer Adhesive Source, and UV Curing Parameters for Examples 1-3

[0087]

[0088]

[0089] Examples 4-10

[0090] The difference between Examples 4-10 and Example 2 is that the source of the UV transfer adhesive is different in Examples 4-10, as detailed in Table 6 below.

[0091] Table 6. Source of UV transfer adhesive in Examples 4-10

[0092] Example UV transfer adhesive source Example 4 Preparation Example 7 Example 5 Preparation Example 8 Example 6 Preparation Example 9 Example 7 Preparation Example 10 Example 8 Preparation of Comparative Example 2 Example 9 Preparation of Comparative Example 3 Example 10 Preparation of Comparative Example 4

[0093] Comparative Example

[0094] Comparative Example 1

[0095] The difference between Comparative Example 1 and Example 6 is that a commercially available UV transfer adhesive was used in Comparative Example 1, while other conditions and parameters remained unchanged.

[0096] Comparative Example 2

[0097] The difference between Comparative Example 2 and Example 6 is that the UV curing pretreatment temperature is different in Comparative Example 2. Comparative Example 2 is subjected to UV curing pretreatment at room temperature (25±1℃), while other aspects remain unchanged.

[0098] Comparative Example 3

[0099] The difference between Comparative Example 3 and Example 6 is that no pre-curing treatment is performed in Comparative Example 3 before UV curing.

[0100] Comparative Example 4

[0101] The difference between Comparative Example 3 and Example 6 is that Comparative Example 3 uses only one curing step in S5, and the curing energy is 1200 mJ / cm². 2 .

[0102] Performance testing

[0103] To verify the transfer effect of the Fresnel lens texture UV transfer process of this application, the Fresnel lens texture UV transfer process was tested in Examples 1-10 and Comparative Examples 1-4 respectively:

[0104] The transfer substrate is an optical PET film with dimensions of 250mm*15mm*0.05mm (length*width*thickness).

[0105] Equipment used: Fresnel lens texture transfer mold and UV curing machine.

[0106] 1. Adhesion test

[0107] The PET transfer film after transfer was subjected to an adhesion test according to ASTM D3359, "Standard Test Criteria for Testing Coating Adhesion by Tape Method". The adhesion strength between the adhesive layer and the transfer substrate was tested and the test results were recorded. See Table 7 below for details.

[0108] (II) Flexibility Test

[0109] Test at room temperature (25±1℃):

[0110] The UV transfer adhesive was cured separately, and the cured UV transfer adhesive layer had a thickness of 0.1 mm and an area of ​​4 cm². 2 Then, the same position of the UV transfer adhesive was repeatedly folded and flattened. After folding and flattening 20 times, the surface of the adhesive layer was observed for any cracks and the test results were recorded. See Table 7 below for details.

[0111] Low temperature (-15±2℃) test:

[0112] The UV transfer adhesive was cured separately, and the cured UV transfer adhesive layer had a thickness of 0.1 mm and an area of ​​4 cm². 2 Then, place the cured adhesive in a low-temperature constant temperature chamber and freeze for 24 hours. Repeat the folding and flattening of the same position of the UV transfer adhesive 20 times. Observe whether there are any cracks on the surface of the adhesive layer and record the test results. See Table 7 below for details.

[0113] (III) Texture tear test

[0114] The transfer film with the Fresnel lens texture after transfer was placed under an observation lamp for observation. The texture tearing was observed and the texture tearing rate was calculated and recorded. See Table 7 below for details. The texture tearing rate was calculated as follows:

[0115] Table 7 Performance test data of Fresnel lens texture UV transfer process

[0116]

[0117]

[0118] Combining Examples 3-4 and 7-8 with Table 7, it can be seen that the addition of modified epoxy acrylate affects the weather resistance, flexibility, and adhesion of the UV transfer adhesive system. When the amount of modified epoxy acrylate in Example 8 is too small, the weather resistance, flexibility, and adhesion of the UV transfer adhesive decrease after UV curing. At the same time, due to the reduced flexibility, the transfer film with Fresnel lens texture obtained after transfer will have texture tearing on the adhesive surface during demolding, reducing the transfer effect of Fresnel lens texture. In Example 7, when ethylenediamine is not added as a crosslinking agent, the flexibility of modified epoxy acrylate decreases, causing the generated UV transfer adhesive to crack after repeated folding and flattening 20 times, reducing flexibility, and increasing the texture tearing of the adhesive layer during demolding of the transfer film with Fresnel lens texture.

[0119] As can be seen from Examples 4-5 and 10, and Table 7, photoinitiators play a significant role in the curing of UV transfer adhesives. When a better ratio of compound photoinitiators is used, the curing efficiency of the UV transfer adhesive is improved. However, when two photoinitiators are used alone in Example 10, the curing efficiency of the UV transfer adhesive is reduced, the intermolecular cross-linking effect is reduced, the flexibility of the UV transfer adhesive is reduced, and the texture tearing of the Fresnel lens texture of the transfer film is increased.

[0120] As can be seen from Examples 5-6 and 9 and Table 7, when an optimal ratio of adhesion promoter is used, the adhesion between the UV transfer adhesive layer and the transfer substrate is improved, and the texture tearing of the transferred Fresnel lens texture is reduced.

[0121] As can be seen from Example 6 and Comparative Example 1 and Table 7, the adhesion between the UV transfer adhesive layer formed by using commercially available UV transfer adhesive and the surface of the transfer substrate is significantly reduced. At the same time, the commercially available UV transfer adhesive has low flexibility, resulting in more texture tearing during the Fresnel lens texture transfer process. In addition, the weather resistance is relatively poor, and the number of cracks in the adhesive layer increases after low temperature testing.

[0122] As can be seen from Example 6 and Comparative Examples 2-4 and Table 7, the Fresnel lens texture UV transfer printing process of this application results in good adhesion between the transferred adhesive layer and the transfer substrate, making it less likely for the transfer substrate to fall off the Fresnel lens texture template, thus improving the transfer efficiency of the Fresnel lens texture and reducing the texture tearing of the resulting transfer film with Fresnel lens texture.

[0123] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A Fresnel lens texture UV transfer process, characterized in that, Includes the following steps: S1. Mold making: Select a metal sheet as the base material, and create a Fresnel lens texture in the effective area of ​​the metal sheet to form a Fresnel lens texture template. S2. Apply transfer adhesive: Apply UV transfer adhesive evenly to the texture area of ​​the Fresnel lens texture template; S3, Rolling and Degassing: The transfer substrate is placed on a Fresnel lens texture template coated with UV transfer adhesive and subjected to uniform rolling and degassing treatment. S4. Pre-curing treatment: After S3 rolling and degassing treatment, the transfer substrate and Fresnel lens texture template are left to stand at 30-40℃ for 5-10 minutes. S5, UV curing: The transfer substrate that has been pre-cured by S4 is subjected to UV curing treatment with Fresnel lens texture template. S6. Demolding: Demolding the transfer substrate after UV curing in S5 from the Fresnel lens texture template to obtain a transfer film with Fresnel lens texture. The UV transfer adhesive used in step S2 is composed of the following raw materials in parts by weight: 20-30 parts acrylate, 30-50 parts modified epoxy acrylate, 15-25 parts reactive diluent, 5-15 parts photoinitiator, 1.5-4 parts antioxidant, 1-3 parts adhesion promoter, and 0.05-0.3 parts polymerization inhibitor. The modified epoxy acrylate is prepared by the following steps: A1: Add 20-30 parts of epoxy resin to 10-20 parts of polypropylene glycol diglycidyl ether and dissolve and mix well; A2: Add 12-22 parts acrylic acid, 1-3 parts diethylamine and 0.5-1.5 parts diethylenetriamine, heat to 86-100℃ and react for 5-7 hours to obtain modified epoxy acrylate; The reactive diluent is composed of tritetrapropylene glycol diacrylate and trimethylolpropane triacrylate in a weight ratio of 1:(0.5-0.8); the adhesion promoter is polyethylene glycol monomethacrylate phosphate.

2. The Fresnel lens texture UV transfer process according to claim 1, characterized in that: The photoinitiator is composed of benzoin dimethyl ether, 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide and diethylamine in a weight ratio of 1:(0.4-0.8):(0.1-0.3).

3. The Fresnel lens texture UV transfer process according to claim 1, characterized in that: The antioxidant is composed of thiol-based benzimidazole and p-phenylenediamine in a weight ratio of 1:(0.1-0.3).

4. The Fresnel lens texture UV transfer process according to claim 1, characterized in that: The polymerization inhibitor is either p-benzoquinone or hydroquinone.

5. The Fresnel lens texture UV transfer process according to claim 1, characterized in that: The UV transfer adhesive is prepared by the following steps: B1: Mix 20-30 parts of acrylate, 30-50 parts of modified epoxy acrylate, 15-25 parts of reactive diluent and 0.05-0.3 parts of polymerization inhibitor, and stir at 25-45℃ to obtain mixture A; B2: Add 5-15 parts of photoinitiator, 1.5-4 parts of antioxidant and 1-3 parts of adhesion promoter to mixture A and mix well to obtain UV transfer adhesive.

6. The Fresnel lens texture UV transfer process according to claim 1, characterized in that: The transfer substrate in step S3 is an optical PET sheet, an optical PC sheet, or an optical polyurethane film, and the thickness of the transfer substrate is 0.01-0.1 mm.

7. The Fresnel lens texture UV transfer process according to claim 1, characterized in that... The photocuring process in step S5 consists of two stages, wherein the photocuring energy in the first stage is 780-980 mJ / cm². 2 The photocuring energy in the second stage is 1150-1250 mJ / cm². 2 .

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