LED curing curved screen protective film material and preparation method thereof

Abstract

The invention belongs to the technical field of curved screen protective film materials, and particularly relates to an LED curing curved screen protective film material and a preparation method thereof. The primer provided by the invention is an LED-cured 100-150-micron recoated repair coating, and is obtained by mixing functional resin, a defoaming agent, a monomer EOEOEA and hydroxyethyl methylacrylate and then adding a premix A, wherein the functional resin, the defoaming agent, the monomer EOEOEA and the hydroxyethyl methylacrylate are mixed and then added into the premix A; the finishing paint is an LED curing hydrophobic hand feeling coating, and is obtained by mixing polycarbonate modified polyurethane, hydrolytic polymaleic anhydride, HEA and a hand feeling auxiliary agent and then adding the premix B into the mixture. The solid content of the product is 100%, LED curing is achieved, and the effects of energy conservation and emission reduction can be achieved. The product has excellent stretchability, rebound resilience, repairability, tearability, hand feeling, stain resistance, high water drop angle and high fitting property to a 3D mobile phone, and does not warp in the use process.

Description

Technical Field

[0001] The present invention belongs to the technical field of curved screen protective film materials, and particularly relates to an LED-cured curved screen protective film material and a preparation method thereof. Background Art

[0002] There are various materials for curved screen protective films. The TPU film (thermoplastic polyurethane film) has good flexibility, can well fit the shape of the curved screen, and avoid the phenomenon of warping; it has a certain self-healing ability, and minor scratches can recover on their own within a period of time; it is relatively thin and will not significantly increase the thickness of the mobile phone. Its impact resistance is slightly weak, and the protection effect is not as good as that of tempered glass film; the touch feeling is poor.

[0003] The PET film (polyester film) is cheap and suitable for users with limited budgets; it is very thin and will not increase the thickness of the mobile phone. Its impact resistance and wear resistance are poor, it is easy to be scratched, and the protection effect is not as good as that of TPU and tempered glass films; on the curved screen, the fitting property may not be as good as that of the TPU film, and it is easy to appear bubbles and warping.

[0004] Tempered films perform excellently in terms of anti-drop and protection, and can provide high hardness and scratch resistance. The fitting degree is relatively poor, especially for the edge part of the curved screen, it is easy to have the situation of poor fitting, resulting in "warping" or dust entering at the edge; ordinary tempered films usually cannot completely cover the curved screen, which may affect the visual experience.

[0005] The UV light-cured film has good coverage, can completely fit the curved screen of the mobile phone, and it is almost invisible at the edge after installation; it not only retains the hardness of the tempered film, but also has the fitting property and flexibility of the soft film; its scratch resistance and durability are relatively excellent. The installation process is relatively complex and requires the use of a UV lamp for curing, which may not be very user-friendly for users with weak hands-on ability; the price is relatively high.

[0006] The liquid nano film can well cover the mobile phone screen whether it is curved or not, and there will be no warping or poor fitting; it can effectively reduce the attachment of fingerprints and oil stains and keep the screen clean. Its impact resistance is weak, and it mainly provides anti-scratch and anti-fouling functions.

[0007] The products on the market mainly use two processes. The first is the two-component curing of polyurethane (PU), which is time-consuming and energy-consuming. The second is photo-curing, which has a strong smell, poor resilience, slow repair, and poor fitting. The present invention has a small smell, fast scratch resilience without leaving traces, excellent repair performance, good fitting for the R corner of the 3D screen, and no warping.

[0008] CN115873495A provides a double-cured polyurethane acrylate resin for preparing a 3D curved screen protective film and a preparation method thereof. This material can improve the fitting property and durability of the protective film through a double-curing process.

[0009] The protective film disclosed in CN213570283U includes a positioning film, a multi-layer composite film used in combination, and a release film. Among them, the oligomer resin layer can undergo a photopolymerization crosslinking reaction under the irradiation of ultraviolet light to form a stable shape with the same curvature as the adherend, and can better adapt to and adhere to the curved screen of electronic products.

[0010] The protective film disclosed in CN118389085A includes a top protective layer, a hardening layer, a PET layer, an acrylic adhesive layer, a thermoplastic polyurethane elastomer layer, a silicone pressure-sensitive adhesive layer, and a fluorine release film layer that are sequentially adhered from top to bottom. This protective film not only has a low cost, can completely adhere to the screen of a curved screen mobile phone without affecting fingerprint unlocking and the sensitivity of the screen, but also has excellent impact resistance.

[0011] CN202211611392 provides a double-curing epoxy acrylate resin that does not require curing treatment and its preparation method. This material can shape the film material through the characteristics of the UV-thermal double-curing layer and adapt to 3D display screens with various curvatures.

[0012] CN202310598889.7 relates to a hot-melt pressure-sensitive adhesive for a curved screen and its preparation method, which can improve the adhesion and durability of the protective film. Summary of the Invention

[0013] The original technology uses two-component curing of PU, which is energy-consuming, inefficient, costly, and has unstable adhesion. The comprehensive performance of the traditional resin used in the photocuring system is relatively flat, and the product made has poor resilience and warps when pasted on the mobile phone.

[0014] To solve the above-mentioned existing technical problems, the present application provides the following technical solutions:

[0015] The present invention adopts a two-layer process and jointly develops a modified LED-curing resin with the supplier, with excellent resilience, tear resistance, adhesion, water contact angle, and hand feel, providing customers with a satisfactory use experience.

[0016] The present invention provides a preparation method for a material of an LED-curing curved screen protective film, including the following steps:

[0017] S11: Prepare premix A and premix B respectively; the premix A is obtained by dissolving a co-initiator and a photoinitiator in the monomer EOEOEA (ethoxyethoxyethyl acrylate); the premix B is obtained by dissolving a co-initiator and a photoinitiator in the monomer HEA (2-hydroxyethyl acrylate);

[0018] S12: Prepare the primer and the topcoat respectively; the primer is obtained by mixing a functional resin, an antifoaming agent, monomer EOEOEA and 2-hydroxyethyl methacrylate (HEMA), and then adding premix A; the topcoat is obtained by mixing polycarbonate modified polyurethane (Blue Road resin 6280), hydrolyzed polymaleic anhydride (HPMA), 2-hydroxyethyl acrylate (HEA) and a hand feeling aid (DSP-3315), and then adding premix B.

[0019] S13: Knife-coat the primer in step S12 on a PET base film and cure it by LED to obtain a primer layer.

[0020] S14: Knife-coat the topcoat in step S12 on the primer layer and cure it by LED to obtain a topcoat layer, completing the preparation of the LED-cured curved screen protective film material.

[0021] The functional resin is purchased from Guangzhou Songda New Material Technology Co., Ltd. and its model is SD535.

[0022] Preferably, in premix A, the mass ratio of the co-initiator, the photoinitiator and monomer EOEOEA is 1:6:20; in premix B, the mass ratio of the co-initiator, the photoinitiator and monomer HEA is 1:6:20.

[0023] Preferably, in the primer, the mass ratio of the functional resin, the antifoaming agent, monomer EOEOEA and 2-hydroxyethyl methacrylate (HEMA) is 54:1:6:26.

[0024] Preferably, in the topcoat, the mass ratio of Blue Road resin 6280, HPMA, HEA and the hand feeling aid DSP-3315 is 38:23:29:4.

[0025] Preferably, both the primer and the topcoat are filtered before spraying; the mesh number of the filtration is 400 meshes.

[0026] Preferably, in step S13, the energy of LED curing is 600 - 800 mJ / cm 2 , and the light intensity is 150 mw / cm 2 ; in step S14, the energy of LED curing is 600 - 800 mJ / cm 2 , and the light intensity is 150 mw / cm 2 .

[0027] Preferably, the thickness of the primer layer is 100 - 150 μm.

[0028] Preferably, the thickness of the topcoat layer is 20 - 30 μm.

[0029] Preferably, in step S14, the energy of LED curing is 600 - 800 mJ / cm2 with a light intensity of 150 mw / cm 2 . .

[0030] Preferably, in the step S14, a release film is covered on the surface of the topcoat layer.

[0031] The present invention also provides an LED-cured curved screen protective film material prepared by the above preparation method.

[0032] The technical solution of the present invention has the following advantages compared with the prior art:

[0033] The primer of the present invention is jointly developed with the supplier to have a high-tensile, tear-resistant, high-rebound, and reparative resin; the topcoat uses a low-shrinkage, high-swelling resin, so that the coating bends in the fitting direction and will not warp when fitting the R corner of the mobile phone. Specific Embodiments

[0034] The following is a further description of the present invention with reference to specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the embodiments cited do not limit the present invention.

[0035] Example 1 Preparation of Primer and Topcoat

[0036] ① Preparation of Primer

[0037] (1) Premixing: 0.5 part of co-initiator KIP-160 and 3 parts of photoinitiator 184 are pre-dissolved in 10 parts of monomer EOEOEA, and the conditions of vortex mixing are: dispersing for 10 minutes at 500 revolutions per minute.

[0038] (2) Mixing: Take 54 parts of functional resin SD535, stir and add 1 part of defoamer (BYK-Special), 6 parts of EOEOEA, 26 parts of HEMA, and then add the premix of the first step, and finally stir to obtain the primer. The stirring conditions are: stirring for 30 minutes at 500 revolutions per minute.

[0039] (3) The primer is prepared.

[0040] ② Preparation of Topcoat

[0041] (1) Premixing: 0.5 part of co-initiator KIP-160 and 3 parts of photoinitiator 184 are pre-dissolved in 10 parts of monomer HEA, and the conditions of vortex mixing are: dispersing for 10 minutes at 500 revolutions per minute.

[0042] (2) Mixing: Take 38 parts of Bluekalu resin 6280, stir and add 23 parts of HPMA, 29 parts of HEA, 4 parts of feel - enhancing agent DSP - 3315, then add the premix from step (1), and stir to finally obtain the topcoat. The stirring conditions are: stir at 500 revolutions per minute for 30 minutes.

[0043] (3) The topcoat is prepared.

[0044] Example 2

[0045] (1) Spray the primer prepared in Example 1 on the PET base film, and cure it with LED. The curing energy is 700 mJ / cm 2 , and the light intensity is 150 mw / cm 2 to obtain a primer layer with a thickness of 150 μm;

[0046] (2) Spray the topcoat prepared in Example 1 on the above - mentioned primer layer, and cure it with LED. The curing energy is 700 mJ / cm 2 , and the light intensity is 150 mw / cm 2 ; then cure it with LED again, with an energy of 700 mJ / cm 2 , and the light intensity is 150 mw / cm 2 to cover and obtain a topcoat layer with a thickness of 30 μm, thus preparing the LED - cured curved - screen protective film material.

[0047] Table 1 Process parameters for the preparation in Example 2

[0048]

[0049] Example 3

[0050] (1) Knife - coat the primer prepared in Example 1 on the PET base film, and cure it with LED. The curing energy is 600 mJ / cm 2 , and the light intensity is 150 mw / cm 2 to obtain a primer layer with a thickness of 150 μm;

[0051] (2) Knife - coat the topcoat prepared in Example 1 on the above - mentioned primer layer, and cure it with LED. The curing energy is 600 mJ / cm 2 , and the light intensity is 150 mw / cm 2 ; then cure it with LED again, with an energy of 600 mJ / cm 2 , and the light intensity is 150 mw / cm 2 to cover and obtain a topcoat layer with a thickness of 20 μm, thus preparing the LED - cured curved - screen protective film material.

[0052] Example 4

[0053] (1) Scrape and coat the primer prepared in Example 1 on the PET base film, and cure it by LED. The curing energy is 800 mJ / cm 2 , and the light intensity is 150 mw / cm 2 to obtain a primer layer with a thickness of 150 μm;

[0054] (2) Scrape and coat the topcoat prepared in Example 1 on the above primer layer, and cure it by LED. The curing energy is 150 mw / cm 2 , and the light intensity is 800 mJ / cm 2 ; then cure it by LED with an energy of 800 mJ / cm 2 , and the light intensity is 150 mw / cm 2 to cover and obtain a topcoat layer with a thickness of 20 μm, and prepare the LED-cured curved screen protective film material.

[0055] Effect Evaluation 1

[0056] Table 2 Performance Test Methods

[0057]

[0058] Table 3 Product Parameters Prepared in Example 2

[0059]

[0060] The prior art CN115926599A discloses a manufacturing method of a film material for protecting a mobile phone curved screen. The prepared film material for protecting a mobile phone curved screen can reach the thickness of traditional substrates (100 - 150 μm) and has flexibility, and at the same time has high stain resistance and high smooth hand feeling that the TPU and TPH substrates do not have. In addition, the present invention shows ideal attachability on any arc surface, and the invention relates to traditional PU thermal curing. Compared with this prior art, the present invention does not require curing, reduces energy consumption and comprehensively improves mechanical properties.

[0061] Obviously, the above embodiments are only examples clearly described and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A method for preparing a LED curing curved screen protective film material, characterized in that: The steps include: S11: preparing premix A and premix B respectively; the premix A is obtained by dissolving a co-initiator and a photoinitiator in a monomer EOEOEA; the premix B is obtained by dissolving a co-initiator and a photoinitiator in a monomer HEA; S12: preparing a primer and a topcoat respectively; the primer is prepared by mixing a functional resin, a defoamer, a monomer EOEOEA and hydroxyethyl methacrylate and then adding premix A; the topcoat is prepared by mixing polycarbonate modified polyurethane, hydrolyzed polymaleic anhydride, HEA and a hand feel aid and then adding premix B; S13: scraping the primer in step S12 onto the PET base film, and curing with LED to obtain a primer layer; S14: applying the topcoat in step S12 on the primer layer, and curing it by LED to obtain a topcoat layer, thereby completing the preparation of the LED-cured curved screen protective film material.

2. The preparation method according to claim 1, characterized in that In the premix A, the mass ratio of the co-initiator, the photoinitiator and the monomer EOEOEA is 1:6:20; in the premix B, the mass ratio of the co-initiator, the photoinitiator and the monomer HEA is 1:6:

20.

3. The preparation method according to claim 1, characterized in that: In the primer, the mass ratio of the functional resin, the defoamer, the monomer EOEOEA and hydroxyethyl methacrylate is 54:1:6:

26.

4. The preparation method according to claim 1, characterized in that: In the topcoat, the mass ratio of Lanco resin 6280, hydrolyzed polymaleic anhydride, HEA and hand feel additive DSP-3315 is 38:23:29:

4.

5. The preparation method according to claim 1, characterized in that: In step S13, the energy of LED curing is 600-800 mJ / cm 2 , light intensity is 150mw / cm 2 In step S14, the energy of LED curing is 600-800mJ / cm 2 , light intensity is 150mw / cm 2 .

6. The preparation method according to claim 1, characterized in that: The thickness of the primer layer is 100-150 μm.

7. The preparation method according to claim 1, characterized in that: The thickness of the topcoat layer is 20-30 μm.

8. The preparation method according to claim 1, characterized in that: In step S14, the energy of LED curing is 600-800 mJ / cm 2 , light intensity is 150mw / cm 2 .

9. The preparation method according to claim 1, characterized in that: In the step S14, a release film is covered on the surface of the topcoat layer.

10. An LED-cured curved screen protective film material prepared by the preparation method according to any one of claims 1 to 9.

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