A UV-Moisture Dual-Curing Coating, its Preparation Method, and its Application

Abstract

This invention belongs to the field of ultraviolet (UV) curable coating technology, and relates to a UV-moisture dual-curing coating, its preparation method, and its application. The UV-moisture dual-curing coating, by weight, comprises the following components: 34-45 parts UV-moisture dual-curing resin, 8-25 parts UV oligomer, 30-50 parts UV monomer, 0.1-8 parts photoinitiator, 0.1-0.4 parts fluorescent agent, 0.1-0.5 parts leveling agent, 0.1-0.5 parts mildew inhibitor, and 0.1-0.5 parts defoamer. The UV-moisture dual-curing coating is free of organic solvents and VOCs, meeting environmental protection requirements. It can cure within seconds under UV light, thereby achieving faster PCB production speed, higher output, and lower costs. When applied to PCBs and their components, this coating quickly cures into a transparent protective film. After curing, it exhibits good adhesion to the substrate, no blistering, elasticity, and wrinkle-free properties.

Description

Technical Field

[0001] This invention belongs to the field of ultraviolet curable coating technology, specifically relating to a UV-moisture dual-curing coating, its preparation method, and its application. Background Technology

[0002] With the development of technology, people's daily lives are undergoing tremendous changes, and more and more electronic products are emerging in all aspects of life. Printed circuit boards (PCBs) are essential components of all electronic products. During use, if the PCB and its components are not protected, defects such as corrosion, mold, deformation, and aging will occur, affecting the quality and lifespan of electronic products. Therefore, the PCB protection process is an indispensable part of electronic product manufacturing. The most common protection method is to coat the PCB surface with conformal coating, which is moisture-proof, mildew-proof, and salt spray-proof, and is a coating with a special formula.

[0003] The most commonly used conformal coating in the industry is UV-cured conformal coating, which forms a transparent protective film after rapid curing, enabling streamlined production on the production line. However, due to the unevenness of the PCB board and the components on it, there are areas that cannot be irradiated by UV light, resulting in the coating not being fully cured, which affects the product quality of the PCB board. Moreover, incomplete curing of the coating during the PCB board coating process also affects the coating production efficiency.

[0004] In view of this, the present invention is hereby proposed. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a UV moisture dual-curing coating, its preparation method, and its application.

[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a UV-moisture dual-curing coating, comprising the following components by weight: 34-45 parts of UV-moisture dual-curing resin, 8-25 parts of UV oligomer, 30-50 parts of UV monomer, 0.1-8 parts of photoinitiator, 0.1-0.4 parts of fluorescent agent, 0.1-0.5 parts of leveling agent, 0.1-0.5 parts of mildew inhibitor, and 0.1-0.5 parts of defoamer.

[0007] Specifically, the UV-moisture dual-curing resin is used as the main component of the dual-curing system, undergoing UV curing and moisture curing reactions, and is the main film-forming substance; the material is 4150 resin produced by Zhanxin Resin Co., Ltd.

[0008] Specifically, the UV oligomer pure UV-curable resin is a high-functional-group, low-polymerization-reactive substance. Its functional groups undergo cross-linking reactions with some of the functional groups in the UV moisture-curable resin, thereby improving the cross-linking density during curing and enhancing the flexibility and adhesion of the coating film. The material is a mixture of UV-4815 resin and UV-400-1 resin produced by Dongguan Jingshang New Material Development Co., Ltd., in a ratio of (3.5~8):1, or a mixture of SD7209 resin and SD016 resin produced by Guangzhou Songda New Material Technology Co., Ltd., in a ratio of (5~8):1.

[0009] Specifically, the UV monomer is used to improve the viscosity and rheology of the system, improve the curing rate and coating performance of the system; the material is at least one of EM-214, EM-212 or EM-70 produced by Changxing Chemical Industry Co., Ltd.; depending on the coating surface effect and curing status, EM-214 or EM-212 can also be compounded with EM-70, with EM-214 or EM-212 as the main component and a small amount of EM-70 added.

[0010] Specifically, the photoinitiator is used to provide the photocuring reaction for the coating material. Under ultraviolet or visible light irradiation, it absorbs light energy and decomposes into free radicals or cations, thereby initiating monomer polymerization, cross-linking, and curing. The material is at least one of the following: model 184, model 819, or model TPO produced by Yuming Chemical (Shanghai) Co., Ltd. Depending on the situation, we can compound model 184 and model 819 in a ratio of (5~4):(3~1); or TPO can be used alone.

[0011] Specifically, the fluorescent agent is used to make certain substances emit blue light under UV light, thereby improving visibility, and is used to check coating defects after the PCB board is coated; the material is the invisible ultraviolet fluorescent agent UVA-A1 produced by Tianjin Saiterui Technology Development Co., Ltd.

[0012] Specifically, the leveling agent is used to improve the leveling effect of the coating material; the material is at least one of BYK-333, BYK-358N or BYK-3558N produced by BYK Additives Shanghai Co., Ltd.; it is recommended to add it alone, and when compounding according to performance requirements, the total amount should not exceed 0.5% of the total formula amount. The preferred compounding is two types, and the recommended ratio is (1~3):1.

[0013] Specifically, the antifungal agent is used to improve the antifungal effect of the coating material; the material is 342 antifungal agent produced by Guangzhou Desong Chemical Co., Ltd.

[0014] Specifically, the defoamer is used to improve the bubble problem of the coating material and eliminate bubbles; the material is at least one of Hemings-Deqian Company's 6800 defoamer or BYK-1790 defoamer produced by BYK Additives Shanghai Co., Ltd. It is recommended to add it alone, and when compounding according to performance requirements, the total amount should not exceed 0.5% of the total formula amount. The recommended ratio for compounding is (1~3):1.

[0015] Secondly, the present invention provides a method for preparing the UV moisture dual-curing coating as described above, comprising the following steps: Step 1: Accurately weigh the UV moisture-curing resin, photoinitiator, and fluorescent agent according to the formula ratio, add them to the container in sequence, heat in a water bath at a specific temperature and stir until all solid particles are dissolved into a uniform and transparent primary liquid. Since the photoinitiator and fluorescent agent used are solids, water bath heating is required. If they are liquids, the heating step can be omitted.

[0016] Step 2: Accurately weigh the UV monomer and UV oligomer according to the formula ratio, add them to the primary liquid, disperse and stir at room temperature to obtain the intermediate solution; Step 3: Accurately weigh the leveling agent, mildew inhibitor, and defoamer according to the formula ratio, add them to the intermediate solution, disperse and stir at room temperature to obtain the desired UV moisture dual-curing coating.

[0017] Specifically, in step 1, stir at 80℃~100℃, at a speed of 500~1000 rpm, and disperse for 5~10 minutes.

[0018] Specifically, in step 2, the dispersion and stirring time is 5 to 10 minutes, and the rotation speed is 500 to 1000 revolutions per minute.

[0019] Specifically, in step 2, the dispersion and stirring time is 5 to 10 minutes, and the rotation speed is 500 to 1000 revolutions per minute.

[0020] Thirdly, the present invention provides a UV-moisture dual-curing coating as described above, or an application of a UV-moisture dual-curing coating prepared by the preparation method described above in PCB board protection.

[0021] Specifically, the UV-moisture dual-curing coating is cured by a combination of UV light curing and moisture reaction curing during use.

[0022] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: The UV-curable moisture-curing coating of this invention contains no organic solvents, is 100% solids, and has no VOCs, meeting environmental protection requirements. It can cure within seconds under UV light, enabling faster PCB production speeds, higher output, and lower costs. When applied to PCBs and their components, the coating quickly cures into a transparent protective film. After curing, it exhibits good adhesion to the substrate, no blistering, and the film is elastic and wrinkle-free.

[0023] The UV-Moisture Dual-Cure Coating of this invention employs a synergistic curing method of light curing + moisture reaction: after initial curing with a UV LED lamp, it can continue to react with moisture in the air to achieve complete curing. The curing principle utilizes the photosensitivity of a photoinitiator (photosensitizer). Under ultraviolet light irradiation, photoinitiation forms excited-state molecules, which decompose into free radicals or ions, causing unsaturated organic matter to undergo polymerization, grafting, cross-linking, and other chemical reactions to achieve curing, transforming from a liquid to a solid state. In areas not exposed to UV light, subsequent curing is achieved through supplementary moisture. Specifically, the isocyanate groups of the UV-Moisture Dual-Cure Resin undergo a cross-linking reaction with the hydroxyl groups of water in the moisture, enhancing coating performance and ensuring sufficient curing in poorly lit areas. Moisture curing typically takes 24 to 72 hours. When using this product, please use it all at once after opening. When not in use, store it in a dark environment, avoiding light exposure to prevent the coating from gelling and becoming unusable. Attached Figure Description

[0024] The accompanying drawings are incorporated in and form part of this specification, and together with the description serve to explain the principles of the invention.

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a flowchart of the preparation method of the present invention. Detailed Implementation

[0027] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples consistent with some aspects of the invention as detailed in the appended claims.

[0028] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0029] This invention provides a UV-moisture dual-curing coating, comprising the following components by weight: 34-45 parts UV-moisture dual-curing resin, 8-25 parts UV oligomer, 30-50 parts UV monomer, 0.1-8 parts photoinitiator, 0.1-0.4 parts fluorescent agent, 0.1-0.5 parts leveling agent, 0.1-0.5 parts mildew inhibitor, and 0.1-0.5 parts defoamer.

[0030] Specifically, the UV-moisture dual-curing resin is used as the main component of the dual-curing system, undergoing UV curing and moisture curing reactions, and is the main film-forming substance; the material is 4150 resin produced by Zhanxin Resin Co., Ltd.

[0031] Specifically, the UV oligomer pure UV-curable resin is a high-functional-group, low-polymerization-reactive substance. Its functional groups undergo cross-linking reactions with some of the functional groups in the UV moisture-curable resin, thereby improving the cross-linking density during curing and enhancing the flexibility and adhesion of the coating film. The material is a mixture of UV-4815 resin and UV-400-1 resin produced by Dongguan Jingshang New Material Development Co., Ltd., in a ratio of (3.5~8):1, or a mixture of SD7209 resin and SD016 resin produced by Guangzhou Songda New Material Technology Co., Ltd., in a ratio of (5~8):1.

[0032] Specifically, the UV monomer is used to improve the viscosity and rheology of the system, improve the curing rate and coating performance of the system; the material is at least one of EM-214, EM-212 or EM-70 produced by Changxing Chemical Industry Co., Ltd.; depending on the coating surface effect and curing status, EM-214 or EM-212 can also be compounded with EM-70, with EM-214 or EM-212 as the main component and a small amount of EM-70 added.

[0033] Specifically, the photoinitiator is used to provide the photocuring reaction for the coating material. Under ultraviolet or visible light irradiation, it absorbs light energy and decomposes into free radicals or cations, thereby initiating monomer polymerization, cross-linking, and curing. The material is at least one of the following: model 184, model 819, or model TPO produced by Yuming Chemical (Shanghai) Co., Ltd. Depending on the situation, we can compound model 184 and model 819 in a ratio of (5~4):(3~1); or TPO can be used alone.

[0034] Specifically, the fluorescent agent is used to make certain substances emit blue light under UV light, thereby improving visibility, and is used to check coating defects after the PCB board is coated; the material is the invisible ultraviolet fluorescent agent UVA-A1 produced by Tianjin Saiterui Technology Development Co., Ltd.

[0035] Specifically, the leveling agent is used to improve the leveling effect of the coating material; the material is at least one of BYK-333, BYK-358N or BYK-3558N produced by BYK Additives Shanghai Co., Ltd.; it is recommended to add it alone, and when compounding according to performance requirements, the total amount should not exceed 0.5% of the total formula amount. The preferred compounding is two types, and the recommended ratio is (1~3):1.

[0036] Specifically, the antifungal agent is used to improve the antifungal effect of the coating material; the material is 342 antifungal agent produced by Guangzhou Desong Chemical Co., Ltd.

[0037] Specifically, the defoamer is used to improve the bubble problem of the coating material and eliminate bubbles; the material is at least one of Hemings-Deqian Company's 6800 defoamer or BYK-1790 defoamer produced by BYK Additives Shanghai Co., Ltd.; it is recommended to add it alone, and the total amount should not exceed 0.5% of the total formula when compounding according to performance requirements. The recommended ratio for compounding is (1~3):1.

[0038] This invention provides a method for preparing the UV-moisture dual-curing coating as described above, comprising the following steps: Step 1: Accurately weigh the UV moisture-curing resin, photoinitiator and fluorescent agent according to the formula ratio, add them to the container in sequence, heat and stir in a water bath at a specific temperature until all solid particles are dissolved into a uniform and transparent primary liquid. Step 2: Accurately weigh the UV monomer and UV oligomer according to the formula ratio, add them to the primary liquid, disperse and stir at room temperature to obtain the intermediate solution; Step 3: Accurately weigh the leveling agent, mildew inhibitor, and defoamer according to the formula ratio, add them to the intermediate solution, disperse and stir at room temperature to obtain the desired UV moisture dual-curing coating.

[0039] Specifically, in step 1, stir at 80℃~100℃, at a speed of 500~1000 rpm, and disperse for 5~10 minutes.

[0040] Specifically, in step 2, the dispersion and stirring time is 5 to 10 minutes, and the rotation speed is 500 to 1000 revolutions per minute.

[0041] Specifically, in step 2, the dispersion and stirring time is 5 to 10 minutes, and the rotation speed is 500 to 1000 revolutions per minute.

[0042] This invention provides an application of the UV-moisture dual-curing coating as described above, or the UV-moisture dual-curing coating prepared by the preparation method described above, in PCB board protection.

[0043] Specifically, the UV-moisture dual-curing coating is cured by a combination of UV light curing and moisture reaction curing during use.

[0044] To demonstrate the effectiveness of the present invention, the following embodiments and comparative examples are provided for verification.

[0045] Example 1 See Figure 1 As shown in the figure, this embodiment provides a method for preparing a UV-curable moisture-curing coating, and the specific steps are as follows: Step 1: Weigh out 34 parts of UV moisture-curing resin (4150), 5 parts of photoinitiator (4 parts of 184 and 1 part of 819), and 0.1 parts of fluorescent agent (UVA-A1) according to the weight proportions. Add them to the dispersion container water bath in sequence, heat and stir in the water bath at 80°C at a stirring speed of 1000 rpm for 5 minutes until all solid particles are dissolved into a uniform and transparent primary liquid. Then remove it from the water bath. Step 2: Weigh out 42 parts of UV monomer (EM-212) and 18 parts of UV oligomer (16 parts of UV-4815 and 2 parts of UV-400-1) according to the weight ratio, add them to the primary liquid, disperse and stir at room temperature for 5 minutes at a speed of 1000 rpm to obtain the intermediate solution. Step 3: Weigh out 0.5 parts of leveling agent, 0.2 parts of mildew inhibitor and 0.2 parts of defoamer according to the weight ratio, add them to the intermediate solution, disperse and stir at room temperature for 10 minutes at a speed of 500 rpm to obtain the desired UV moisture dual-curing coating.

[0046] Example 2 This embodiment provides a method for preparing a UV-curable moisture-curing coating, the specific steps of which are as follows: Step 1: Weigh out 45 parts of UV moisture-curing resin (4150), 6 parts of photoinitiator (4 parts of 184 and 2 parts of 819), and 0.2 parts of fluorescent agent (UVA-A1) according to the weight proportions. Add them to the dispersion container water bath in sequence, heat and stir in the water bath at 90°C at a stirring speed of 800 rpm for 8 minutes until all solid particles are dissolved into a uniform and transparent primary liquid. Then remove it from the water bath. Step 2: Weigh out 31 parts of UV monomer (25 parts of EM-212 and 6 parts of EM-70) and 18 parts of UV oligomer (15 parts of UV-4815 and 3 parts of UV-400-1) according to the weight ratio, add them to the primary liquid, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the intermediate solution; Step 3: Weigh out 0.4 parts of leveling agent, 0.3 parts of mildew inhibitor and 0.1 parts of defoamer according to the weight ratio, add them to the intermediate solution, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the desired UV moisture dual-curing coating.

[0047] Example 3 This embodiment provides a method for preparing a UV-curable moisture-curing coating, the specific steps of which are as follows: Step 1: Weigh out 45 parts of UV moisture-curing resin (4150), 5 parts of photoinitiator (TPO), and 0.2 parts of fluorescent agent (UVA-A1) according to the weight proportions. Add them to the dispersion container water bath in sequence, heat and stir in the water bath at 100°C at a stirring speed of 500 rpm for 10 minutes until all solid particles are dissolved into a uniform and transparent primary liquid. Then remove it from the water bath. Step 2: Weigh out 31 parts of UV monomer (25 parts of EM-214 and 6 parts of EM-70) and 8 parts of UV oligomer (7 parts of SD7209 and 1 part of SD-016) according to the weight ratio, add them to the primary liquid, disperse and stir at room temperature for 10 minutes at a speed of 500 rpm to obtain the intermediate solution. Step 3: Weigh out 0.5 parts of leveling agent, 0.1 parts of mildew inhibitor and 0.2 parts of defoamer according to the weight ratio, add them to the intermediate solution, disperse and stir at room temperature for 5 minutes at a speed of 1000 rpm to obtain the desired UV moisture dual-curing coating.

[0048] Example 4 This embodiment provides a method for preparing a UV-curable moisture-curing coating, the specific steps of which are as follows: Step 1: Weigh out 41 parts of UV moisture-curing resin (4150), 5 parts of photoinitiator (5 parts of 184 and 3 parts of 819), and 0.1 parts of fluorescent agent (UVA-A1) according to the weight proportions. Add them to the dispersion container water bath in sequence, heat and stir in the water bath at 90°C at a stirring speed of 800 rpm for 8 minutes until all solid particles are dissolved into a uniform and transparent primary liquid. Then remove it from the water bath. Step 2: Weigh out 30 parts of UV monomer (EM-214) and 22 parts of UV oligomer (16 parts of UV-4815 and 4 parts of UV-400-1) according to the weight ratio, add them to the primary liquid, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the intermediate solution. Step 3: Weigh out 0.1 parts of leveling agent, 0.4 parts of mildew inhibitor and 0.4 parts of defoamer according to the weight ratio, add them to the intermediate solution, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the desired UV moisture dual-curing coating.

[0049] Comparative Example 1 This embodiment provides a method for preparing a UV-curable moisture-curing coating, the specific steps of which are as follows: Step 1: Weigh out 34 parts of UV moisture-curing resin (6133N-15 Changxing Chemical), 5 parts of photoinitiator (4 parts of 184 and 1 part of 819), and 0.1 parts of fluorescent agent (UVA-A1) according to the weight proportions. Add them to the dispersion container water bath in sequence, heat and stir at 90°C with a stirring speed of 800 rpm, disperse for 8 minutes until all solid particles are dissolved into a uniform and transparent primary liquid, and then remove it from the water bath. Step 2: Weigh out 42 parts of UV monomer (EM-212) and 18 parts of UV oligomer (16 parts of UV-4815 and 2 parts of UV-400-1) according to the weight ratio, add them to the primary liquid, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the intermediate solution. Step 3: Weigh out 0.5 parts of leveling agent, 0.2 parts of mildew inhibitor and 0.2 parts of defoamer according to the weight ratio, add them to the intermediate solution, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the desired coating.

[0050] Comparative Example 2 This embodiment provides a method for preparing a UV-curable moisture-curing coating, the specific steps of which are as follows: Step 1: Weigh out 34 parts of UV moisture-curing resin (4150), 5 parts of photoinitiator (4 parts of 184 and 1 part of 819), and 0.1 parts of fluorescent agent (UVA-A1) according to the weight proportions. Add them to the dispersion container water bath in sequence, heat and stir in the water bath at 90°C at a stirring speed of 800 rpm for 8 minutes until all solid particles are dissolved into a uniform and transparent primary liquid. Then remove it from the water bath. Step 2: Weigh 42 parts of UV monomer (EM-212) and 18 parts of UV oligomer (UV-4815) according to the weight ratio, add them to the primary liquid, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the intermediate solution; Step 3: Weigh out 0.5 parts of leveling agent, 0.2 parts of mildew inhibitor and 0.2 parts of defoamer according to the weight ratio, add them to the intermediate solution, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the desired coating.

[0051] Comparative Example 3 This embodiment provides a method for preparing a UV-curable moisture-curing coating, the specific steps of which are as follows: Step 1: Weigh out 34 parts of UV moisture-curing resin (4150), 5 parts of photoinitiator (4 parts of 184 and 1 part of 819), and 0.1 parts of fluorescent agent (UVA-A1) according to the weight proportions. Add them to the dispersion container water bath in sequence, heat and stir in the water bath at 90°C at a stirring speed of 800 rpm for 8 minutes until all solid particles are dissolved into a uniform and transparent primary liquid. Then remove it from the water bath. Step 2: Weigh 42 parts of UV monomer (EM-212) and 18 parts of UV oligomer (UV-400-1) according to the weight ratio, add them to the primary liquid, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the intermediate solution. Step 3: Weigh out 0.5 parts of leveling agent, 0.2 parts of mildew inhibitor and 0.2 parts of defoamer according to the weight ratio, add them to the intermediate solution, disperse and stir at room temperature for 8 minutes at a speed of 800 rpm to obtain the desired coating.

[0052] To further verify the effectiveness of the present invention, the inventors conducted the following performance tests on the coating materials prepared in Examples 1-3 and Comparative Examples 1-3.

[0053] The IPC-CC-830C CN≤Identification and Performance Standards for Electrical Insulation Compounds for Printed Circuit Components≥ was used to test 10 properties, including appearance, fluorescence, flexibility, thermal shock, temperature and humidity aging, mildew resistance, flammability, dielectric withstand voltage (DWV), humidity and insulation resistance (MIR), and Fourier transform infrared spectroscopy (FTIR). The test results are shown in Table 1.

[0054] Table 1 As shown in Table 1, the UV-curable moisture dual-curing resin (Zhanxin 4150 dual-curing resin) used in Examples 1-4 of this invention, along with coatings using a combination of photoinitiators 184 and 819 and TPO photoinitiator, exhibited excellent comprehensive performance in mechanical properties, dielectric withstand voltage (DWV), humidity, and insulation resistance (MIR). In contrast, Comparative Example 1, which used other types of UV-curable moisture dual-curing resins, failed to meet the standards in several aspects. This is because both 6133N and 4150 are UV-curable and moisture-curing resins. The isocyanate content of 6133N resin is much higher than that of 4150 resin. During UV irradiation, the photoinitiator absorbs UV light energy to generate free radicals. The resin is occupied by isocyanates, which can initiate polymerization reactions with free radicals. The resulting long-chain or network polymer has insufficient density, and the coating film becomes sticky after UV irradiation, which does not meet the requirements of PCB circuit board construction. Furthermore, its isocyanates are very easy to react with surrounding substances containing hydroxyl groups because of their high content. Moreover, unused materials during construction are also very easy to react, resulting in a short activation period.

[0055] The test results of Comparative Example 2 show that when all UV oligomers are made of specially modified UV acrylic resin, after UV irradiation reaction, the paint film is not completely dry, has a tackiness when touched, and its thermal shock, DWV and MIR do not meet the requirements. The test results of Comparative Example 3 show that when all UV oligomers are hexafunctional polyurethane acrylic UV resin, the paint film surface is almost completely dry after UV irradiation, with a high crosslinking density. This results in excessively high hardness, a brittle paint film, and poor flexibility. This is because this resin has high functionality and many reactive groups involved in UV light irradiation, leading to a faster reaction and a brittle paint film. Therefore, based on the respective characteristics of these two oligomers, a compound formulation is used to balance their respective advantages and disadvantages.

[0056] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention.

[0057] It should be understood that the present invention is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A UV-curable moisture-curing coating, characterized in that, The product comprises the following components by weight: 34-45 parts UV moisture-curing resin, 8-25 parts UV oligomer, 30-50 parts UV monomer, 0.1-8 parts photoinitiator, 0.1-0.4 parts fluorescent agent, 0.1-0.5 parts leveling agent, 0.1-0.5 parts mildew inhibitor, and 0.1-0.5 parts defoamer.

2. The UV-Moisture Dual-Curing Coating according to claim 1, characterized in that, The UV-curable moisture-curing resin is 4150 resin.

3. The UV-curable moisture-curing coating according to claim 1, characterized in that, The UV oligomer is a mixture of UV-4815 resin and UV-400-1 resin, or a mixture of SD7209 resin and SD016 resin.

4. The UV-Moisture Dual-Curing Coating according to claim 1, characterized in that, The UV monomer is at least one of EM-214, EM-212 or EM-70.

5. A method for preparing a UV-curable moisture-curing coating according to any one of claims 1 to 4, characterized in that, Includes the following steps: Step 1: Weigh the UV moisture-curing resin, photoinitiator and fluorescent agent according to the formula ratio, add them to the container in sequence, heat in a water bath at a specific temperature and stir to obtain the primary liquid; Step 2: Weigh the UV monomer and UV oligomer according to the formula ratio, add them to the primary liquid, disperse and stir to obtain the intermediate solution; Step 3: Weigh the leveling agent, mildew inhibitor and defoamer according to the formula ratio, add them to the intermediate solution, disperse and stir to obtain the desired UV moisture dual-curing coating.

6. The preparation method according to claim 5, characterized in that, In step 1, stir at 80℃~100℃, at a speed of 500~1000 rpm, and disperse for 5~10 minutes.

7. The preparation method according to claim 5, characterized in that, In step 2, the dispersion and stirring time is 5 to 10 minutes, and the rotation speed is 500 to 1000 revolutions per minute.

8. The preparation method according to claim 5, characterized in that, In step 2, the dispersion and stirring time is 5 to 10 minutes, and the rotation speed is 500 to 1000 revolutions per minute.

9. The application of a UV-curable moisture-curing coating as described in any one of claims 1 to 4, or a UV-curable moisture-curing coating prepared by any one of claims 5 to 8, in PCB board protection.

10. The application according to claim 9, characterized in that, The UV-moisture dual-curing coating is cured by a combination of UV light curing and moisture reaction curing during use.

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