A uv-led and moisture dual-curing three-protection paint, and a preparation method and application thereof

Abstract

The application belongs to the technical field of paint, and discloses a UV-LED and moisture dual-curing three-proof paint, a preparation method and application thereof. The UV-LED and moisture dual-curing three-proof paint comprises a polyurethane acrylate prepolymer, an acrylate modified isocyanate prepolymer, a photoinitiator and an additive; the polyurethane acrylate prepolymer contains urethane groups and acrylate double bonds. The UV-LED and moisture dual-curing three-proof paint formed by the specific polyurethane acrylate prepolymer, the acrylate modified isocyanate prepolymer and other components can solve the problem of oxygen inhibition of UV-LED ultraviolet lamp curing; secondly, the adhesion and impact resistance are improved by introducing the polyurethane segment; and the application adopts the UV and moisture dual-curing mode, and the shadow area can also be cured, the cured adhesive film has the characteristics of flexibility and toughness, and can maintain excellent protection ability in high-low temperature impact or high temperature and high humidity environment, and has good popularization prospect.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of paint, and particularly relates to a UV-LED and moisture dual-curing three-proof paint as well as a preparation method and application thereof. BACKGROUND

[0002] The UV three-proof paint is used for preventing the circuit board and other related components from being eroded by the environment after forming a transparent protective paint film through UV irradiation. The three-proof paint needs to have good high and low temperature resistance, and has superior moisture resistance, dust resistance, corrosion resistance, pollution resistance, shock resistance, insulation and other properties.

[0003] The traditional three-proof paint is cured by using a UV mercury lamp, and the reason is that the mercury lamp emits light waves in the full waveband of UVA, UVB and UVC, wherein UVA: 320-400 nm; UVB: 290-320 nm; UVC: 100-290 nm. Through the collocation of photoinitiators, the UVA and UVB waveband light can be absorbed to initiate the reaction. Since the waveband is wide, the curing efficiency is high, the influence of oxygen inhibition can be overcome, and a smooth, flat and dry three-proof paint film (a dry surface does not stick fingerprints and does not adsorb dust) can be obtained. However, it cannot be denied that the mercury lamp also has many problems. The mercury lamp not only emits ultraviolet light, but also emits a large amount of infrared light, which brings a large amount of heat and has an adverse effect on production control. The machine needs to be preheated before work, the production efficiency is low, the energy consumption is high, and the lamp contains heavy metals, which is not safe.

[0004] In recent years, with the development of UV-LED ultraviolet lamps, the research and development of long-waveband high-efficiency photoinitiators have made breakthrough progress, and UV-LED ultraviolet lamp curing has been greatly promoted and applied. Compared with the traditional mercury lamp curing, the UV-LED has the following advantages. The emission wavelength is narrow, the wavelength is mainly 365 nm, 395 nm and 405 nm, and a large amount of heat is not generated during the curing process, so the application is more extensive (for example, suitable for the protection of heat-sensitive components). Secondly, the UV-LED ultraviolet lamp curing can be used immediately without preheating, and the production efficiency is high and the energy consumption is lower. The service life of the lamp tube is long, and the cost is more advantageous. However, there are also some differences from the mercury lamp. First of all, the wavelength peak of the UV-LED ultraviolet lamp light source is single, and the commonly used UV-LED ultraviolet lamp light source wavelength is 365 nm, the wavelength range is narrow, and the power and irradiation are lower compared with the mercury lamp, which leads to obvious oxygen inhibition. The surface of the cured glue film is sticky, so different requirements are put forward for the three-proof paint used in conjunction. Secondly, the new equipment of various downstream customers has adopted UV-LED ultraviolet lamp light sources.

[0005] Therefore, it is urgent to provide a three-proof paint suitable for UV-LED ultraviolet lamp, which solves the problem of oxygen inhibition of UV-LED ultraviolet lamp curing. SUMMARY

[0006] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application provides a UV-LED and moisture dual-curing three-proofing paint, a preparation method and application thereof, which can solve the oxygen inhibition problem of UV-LED ultraviolet lamp curing.

[0007] The UV-LED and moisture dual-curing three-proofing paint provided by the present application can solve the oxygen inhibition problem of UV-LED ultraviolet lamp curing by synthesizing polyurethane acrylate prepolymer and acrylate modified isocyanate prepolymer, and matching a suitable photoinitiator system. In addition, the adhesion and impact resistance are improved by introducing polyurethane segments. The UV and moisture dual-curing method can also cure the shadow area. The cured film has both flexibility and toughness, and maintains excellent protection capability in high-low temperature impact or high temperature and high humidity environment, which has good popularization prospect.

[0008] The first aspect of the present application provides a UV-LED and moisture dual-curing three-proofing paint.

[0009] Specifically, a UV-LED and moisture dual-curing three-proofing paint comprises polyurethane acrylate prepolymer, acrylate modified isocyanate prepolymer, photoinitiator and auxiliary agent.

[0010] The polyurethane acrylate prepolymer contains urethane groups and acrylate double bonds.

[0011] Preferably, the auxiliary agent comprises at least one of active diluent, coupling agent, leveling agent, defoaming agent, water removal agent and fluorescent agent, and further preferably, the auxiliary agent comprises active diluent, coupling agent, leveling agent, defoaming agent, water removal agent and fluorescent agent.

[0012] Preferably, the photoinitiator is selected from at least one of 2-hydroxy-2-methyl-1-phenylpropanone (1173), 1-hydroxy-cyclohexyl-phenyl ketone (184), 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide (TPO), 2,4,6-trimethylbenzoyl phenyl phosphonic acid ethyl ester (TPO-L), methyl benzoylformate, benzophenone, and further preferably, the photoinitiator is 1-hydroxy-cyclohexyl-phenyl ketone (184) and 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide (TPO) or 2,4,6-trimethylbenzoyl phenyl phosphonic acid ethyl ester (TPO-L). 184 is a high-efficiency type I radical non-yellowing photoinitiator, TPO or TPO-L is a high-efficiency type I radical photoinitiator, which has a very wide absorption wavelength range, and the effective absorption peak is 350-400 nm, which can be used for initiating ultraviolet polymerization of unsaturated prepolymer system. This kind of initiator has the following three characteristics: fast curing, yellowing resistance and low odor.

[0013] Preferably, the reactive diluent is selected from at least one of isobornyl acrylate, tetrahydrofurfuryl acrylate, 4-tert-butylcyclohexyl acrylate, acryloyl morpholine, lauryl acrylate, dicyclopentenyl acrylate, 2-phenoxyethyl acrylate, ethoxylated tetrahydrofurfuryl acrylate, propoxylated tetrahydrofurfuryl acrylate, and cyclotrimethylolpropane formal acrylate, isobornyl methacrylate, tetrahydrofurfuryl methacrylate, tripropyleneglycol diacrylate, polyethyleneglycol diacrylate; further preferably, the reactive diluent is isobornyl acrylate, ethoxylated tetrahydrofurfuryl acrylate, and tripropyleneglycol diacrylate.

[0014] Preferably, the coupling agent is a siloxane coupling agent selected from at least one of A151 (vinyl triethoxysilane), A171 (vinyl trimethoxysilane), A172 (vinyl tri(beta-methoxyethoxysilane), A174 methacryloyloxypropyl trimethoxysilane.

[0015] Preferably, the leveling agent is at least one of polyether siloxane-copolymer TEGO Glide 432, TEGO 466, TEGO 435, TEGO 410, BYK-306, BYK-331, BYK-349, BYK-3500, or BYK-3570.

[0016] Preferably, the defoaming agent is at least one of BYK-045, BYK-141, BYK-320, BYK-067A, BYK-088, TEGO Foamex N, TEGO airex 900.

[0017] Preferably, the water scavenger is p-toluenesulfonyl isocyanate (TI) from Borcher, Germany.

[0018] Preferably, the fluorescent agent is Tinopal OB from BASF, Germany.

[0019] Preferably, the UV-LED and moisture dual-curing three-protection paint comprises, by weight fraction, 8-35 parts of polyurethane acrylate prepolymer, 8-35 parts of acrylate-modified isocyanate prepolymer, 0.5-12 parts of photoinitiator, and 20-70 parts of auxiliary agent; further preferably, the UV-LED and moisture dual-curing three-protection paint comprises, by weight fraction, 10-30 parts of polyurethane acrylate prepolymer, 10-30 parts of acrylate-modified isocyanate prepolymer, 1-10 parts of photoinitiator, and 32.061-65 parts of auxiliary agent.

[0020] Preferably, the UV-LED and moisture dual-curing three-protection paint comprises, by weight fraction, the following components:

[0021] Polyurethane acrylate prepolymer 10-30 parts

[0022] Acrylate modified isocyanate prepolymer 10-30 parts

[0023] Photoinitiator 1-10 parts

[0024] Active diluent 30-50 parts

[0025] Coupling agent 1-5 parts

[0026] Leveling agent 1-5 parts

[0027] Defoamer 0.01-2 parts

[0028] Water scavenger 0.05-2 parts

[0029] Fluorescent agent 0.001-1 part.

[0030] The second aspect of the present application provides a preparation method of a UV-LED and moisture dual-curing three-protection paint.

[0031] Specifically, the preparation method of the UV-LED and moisture dual-curing three-protection paint comprises the following steps:

[0032] Mixing the components to obtain the UV-LED and moisture dual-curing three-protection paint.

[0033] Preferably, the raw materials for preparing the polyurethane acrylate prepolymer include a difunctional polyester polyol, a difunctional isocyanate monomer, and a hydroxyl acrylic monomer; the difunctional polyester polyol is polycarbonate polyol. The polycarbonate polyol is resistant to hydrolysis and has excellent anti-yellowing performance.

[0034] For example, the difunctional polyester polyol is Kolon C2090, Asahi Kasei T5652, and Ube PH200, etc.

[0035] Preferably, the difunctional isocyanate monomer is selected from at least one of isophorone diisocyanate IPDI, cyclohexane dimethylene diisocyanate HXDI, or 4,4'-diisocyanate dicyclohexyl methane HMDI. These are non-yellowing type difunctional isocyanates.

[0036] Preferably, the hydroxyl acrylic monomer includes hydroxyethyl acrylate.

[0037] Preferably, the weight ratio of the difunctional polyester polyol, the difunctional isocyanate monomer, and the hydroxyl acrylic monomer is 60-100: (20-40): (10-40), and further preferably 80-100: (20-40): 25.

[0038] Preferably, the raw materials for preparing the polyurethane acrylate prepolymer further include a reactive diluent, an antioxidant, a polymerization inhibitor, and a catalyst.

[0039] Preferably, the process for preparing the polyurethane acrylate prepolymer includes the following steps:

[0040] The two functional polyester polyols are subjected to dehydration treatment, cooled, and then the reactive diluent, antioxidant, and polymerization inhibitor are added, stirred and mixed, and then the two functional isocyanate monomers are added, stirred, heated, and reacted, and then the catalyst is added to continue the reaction, and after the reaction is completed, the temperature is lowered, the hydroxyl acrylate monomers are added, and the reaction is continued to obtain the polyurethane acrylate prepolymer.

[0041] Further preferably, the process for preparing the polyurethane acrylate prepolymer includes the following steps:

[0042] 80-100 g of polycarbonate diol is added to a three-necked flask, subjected to dehydration treatment at 110-120℃ for 1-2 h until the water content is less than 1000 ppm, cooled to a temperature lower than 30℃, 20-30 g of isobornyl acrylate (water content <1000 ppm) and 0.1-0.5 g of antioxidant and 0.01-0.05 ppm of polymerization inhibitor are added, stirred until completely dissolved, 20-40 g of IPDI is added, and the stirring and mixing is continued for 5-10 min, then slowly heated to 60-65℃, and reacted at this temperature for 1.5 h, then heated to 80-85℃, and 0.01-0.05 g of dibutyltin dilaurate is added, and the reaction is continued for 1-1.5 h until the NCO content is ≤ the designed theoretical value, then cooled to 60-65℃, 10-40 g of hydroxyethyl acrylate is added, and reacted at 85-88℃ for 2.5-3 h until there is no hydroxyl peak in the infrared and the NCO content is 0.1-0.5%, and then cooled and discharged to obtain the polyurethane acrylate prepolymer.

[0043] The polyurethane acrylate prepolymer of the present application has two functional carbon-carbon double bonds and urethane bonds, the two functional carbon-carbon double bonds can improve the photocuring rate, the introduced polyurethane segment can improve the adhesion, flexibility, and impact resistance of the film; secondly, it is matched with a composite photoinitiating system suitable for 365 nm absorption band, has high initiation efficiency in UV-LED narrow band, solves the problem of UV-LED curing oxygen inhibition (poor surface drying), and can be self-cured by moisture, that is, can effectively protect dark components. In addition, the present application is also excellent in electrical and moisture and heat aging resistance, and provides a feasible solution for UV-LED curing of three-proofing paint.

[0044] Preferably, the raw materials for preparing the polyurethane acrylate prepolymer further include a reactive diluent, an antioxidant, a polymerization inhibitor, and a catalyst.

[0045] Preferably, the raw materials for preparing the acrylate-modified isocyanate prepolymer further comprise an antioxidant and a polymerization inhibitor.

[0046] Preferably, the hydroxy acrylic monomer is hydroxyethyl acrylate.

[0047] Preferably, the multifunctional isocyanate is HDI trimer, such as Wanhua HT-100, Covestro N3300 or Asahi Kasei TKA, etc.

[0048] The acrylate-modified isocyanate prepolymer structure comprises C=C double bonds and partially unreacted NCO active functional groups, the NCO groups can provide moisture curing, and the C=C double bonds can be polymerized with other olefin resins and monomers to form a polymer.

[0049] Preferably, the preparation process of the acrylate-modified isocyanate prepolymer comprises the following steps:

[0050] The multifunctional isocyanate monomer, antioxidant and polymerization inhibitor are mixed, stirred and heated, then the hydroxy acrylic monomer is added, reacted to obtain the acrylate-modified isocyanate prepolymer.

[0051] Further preferably, the preparation process of the acrylate-modified isocyanate prepolymer comprises the following steps:

[0052] 80-100 g of HDI trimer, 0.1-0.5 g of antioxidant and 0.01-0.05 g of polymerization inhibitor are added into a reaction kettle, heated to 45-50℃, stirred for 5-10 min, then 8-15 g of hydroxyethyl acrylate is added, the reaction temperature is controlled at 85-88℃, and the reaction is carried out for 2.5-3 h, the NCO content is tested to be about 10-16%, and the acrylate-modified isocyanate prepolymer is prepared.

[0053] The third aspect of the present application provides an application of the UV-LED and moisture dual-curing three-protection paint.

[0054] The application of the above UV-LED and moisture dual-curing three-protection paint in electronic products.

[0055] Compared with the prior art, the present application has the following beneficial effects:

[0056] The UV-LED and moisture dual-curing three-proofing paint provided by the present application comprises a polyurethane acrylate prepolymer, an acrylate modified isocyanate prepolymer, a photoinitiator and an auxiliary agent; the polyurethane acrylate prepolymer contains urethane groups and acrylate double bonds. The UV-LED and moisture dual-curing three-proofing paint formed by the specific polyurethane acrylate prepolymer, the acrylate modified isocyanate prepolymer and other components can solve the problem of oxygen inhibition of UV-LED ultraviolet lamp curing; secondly, the introduction of the polyurethane segment improves the adhesion and impact resistance, and the present application adopts the UV and moisture dual-curing mode, which can also cure the shadow area, and the cured film has the characteristics of flexibility and toughness, and can maintain excellent protection capability in high-low temperature impact or high temperature and high humidity environment, and has a good popularization prospect. DETAILED DESCRIPTION

[0057] In order to make the skilled in the art more clearly understand the technical solutions of the present application, the following examples are used for illustration. It should be pointed out that the following examples do not constitute a limitation on the scope of protection required by the present application.

[0058] The raw materials, reagents or devices used in the following examples are commercially available or can be obtained by known methods unless otherwise specified.

[0059] The antioxidant used in the following examples or comparative examples is antioxidant 1010, and the polymerization inhibitor is p-methoxyphenyl methyl ether MEHQ.

[0060] The active diluent is composed of isobornyl acrylate and tetrahydrofuran acrylate in a volume ratio of 1:1.

[0061] The photoinitiator is composed of 1-hydroxy-cyclohexyl-phenyl ketone (184) and 2,4,6-trimethylbenzoyl phenyl phosphonic acid ethyl ester (TPO-L) in a weight ratio of 3:2.

[0062] The coupling agent is composed of A171 (vinyl trimethoxysilane) and A174 methacryloyl propyl trimethoxysilane) in a weight ratio of 1:1.

[0063] The leveling agent is BYK-349.

[0064] The defoaming agent is BYK-045.

[0065] The water removal agent is German Borcher p-toluenesulfonyl isocyanate (TI).

[0066] The fluorescent agent is Tinopal OB of Germany BASF.

[0067] Preparation Example 1: Preparation of polyurethane acrylate prepolymer A

[0068] Into a three-necked flask, 90 g polycarbonate diol T5652 was added and dehydrated at 120 °C for 2 h until the water content was less than 1000 ppm. The temperature was lowered to below 30 °C, 25 g isobornyl acrylate (water content < 1000 ppm) and antioxidants and polymerization inhibitors were added, and stirred until completely dissolved. Then 35 g IPDI was added and stirred for 10 min. The temperature was then slowly raised to 65 °C and reacted at this temperature for 1.5 h. Then the temperature was raised to 85 °C and dibutyl tin dilaurate was added (antioxidant was added at 0.5% of the total mass of polycarbonate diol T5652 and isobornyl acrylate, polymerization inhibitor was added at 0.04% of the total mass of polycarbonate diol T5652 and isobornyl acrylate, and dibutyl tin dilaurate was added at 0.02% of the total mass of polycarbonate diol T5652 and isobornyl acrylate). The reaction was continued for 1.5 h until the NCO content was ≤ the designed theoretical value. Then the temperature was lowered to 60 °C, 25 g hydroxyethyl acrylate was added, and reacted at 86 °C for 3 h until no hydroxyl peak was observed by infrared and the NCO content was 0.4%. The temperature was lowered and the product was discharged. A polyurethane acrylate prepolymer was obtained.

[0069] Preparation Example 2: Preparation of polyurethane acrylate prepolymer B:

[0070] Into a three-necked flask, 90 g polycarbonate diol T5652 was added and dehydrated at 120 °C for 2 h until the water content was less than 1000 ppm. The temperature was lowered to below 30 °C, 25 g isobornyl acrylate (water content < 1000 ppm) and antioxidants and polymerization inhibitors were added, and stirred until completely dissolved. Then 35 g IPDI was added and stirred for 10 min. The temperature was then slowly raised to 65 °C and reacted at this temperature for 1.5 h. Then the temperature was raised to 85 °C and dibutyl tin dilaurate was added (antioxidant was added at 0.5% of the total mass of polycarbonate diol T5652 and isobornyl acrylate, polymerization inhibitor was added at 0.04% of the total mass of polycarbonate diol T5652 and isobornyl acrylate, and dibutyl tin dilaurate was added at 0.02% of the total mass of polycarbonate diol T5652 and isobornyl acrylate). The reaction was continued for 1.5 h until the NCO content was ≤ the designed theoretical value. Then the temperature was lowered to 60 °C, 25 g hydroxyethyl acrylate was added, and reacted at 86 °C for 3 h until no hydroxyl peak was observed by infrared and the NCO content was 0.4%. The temperature was lowered and the product was discharged. A polyurethane acrylate prepolymer was obtained.

[0071] Preparation Example 3: Preparation of polyurethane acrylate prepolymer C:

[0072] Into a three-necked flask, 90 g of BASF polytetrahydrofuran glycol PolyTHF 2000 was added and dehydrated at 120 °C for 2 h until the water content was less than 1000 ppm, and then cooled to a temperature below 30 °C, 25 g of isobornyl acrylate (water content < 1000 ppm) and antioxidants and polymerization inhibitors were added, stirred until completely dissolved, then 35 g of IPDI was added, and the stirring was continued for 10 min, then slowly heated to 65 °C, and reacted at this temperature for 1.5 h, then heated to 85 °C, and then added dibutyltin dilaurate (antioxidant was added at 0.5% of the total mass of BASF polytetrahydrofuran glycol PolyTHF 2000 and isobornyl acrylate, and the polymerization inhibitor was added at 0.04% of the total mass of BASF polytetrahydrofuran glycol PolyTHF 2000 and isobornyl acrylate, and the dibutyltin dilaurate was added at 0.02% of the total mass of BASF polytetrahydrofuran glycol PolyTHF 2000 and isobornyl acrylate), and the reaction was continued for 1.5 h until the NCO content was ≤ the designed theoretical value, then cooled to 60 °C, and 25 g of hydroxyethyl acrylate was added, and reacted at 86 °C for 3 h until no hydroxyl peak was observed by infrared, and the NCO content was 0.4%, and then cooled and discharged to obtain a polyurethane acrylate prepolymer.

[0073] Preparation Example 4: Preparation of an acrylate-modified isocyanate prepolymer

[0074] Into a reaction kettle, 90 g of HDI trimer HT-100, 0.2 g of antioxidant and 0.02 g of polymerization inhibitor were added, and heated to 50 °C and stirred for 10 min, then 12 g of hydroxyethyl acrylate was added, the reaction temperature was controlled at 88 °C, and reacted for 3 h, and the NCO content was about 14%, and then discharged to obtain an acrylate-modified isocyanate prepolymer.

[0075] Example 1

[0076] A UV-LED and moisture dual-curing three-protection paint, by weight fraction, includes the following components:

[0077] Polyurethane acrylate prepolymer A 25 parts

[0078] Acrylate-modified isocyanate prepolymer 25 parts

[0079] Active diluent 39.5 parts

[0080] Photoinitiator 5 parts

[0081] Coupling agent 2 parts

[0082] Leveling agent 1.8 parts

[0083] Defoaming agent 0.5 parts

[0084] Water removal agent 1 part

[0085] Fluorescent agent 0.2 parts.

[0086] A preparation method of a UV-LED and moisture dual-curing three-protection paint, comprising the following steps:

[0087] Disperse with a star-shaped stirrer, first set the stirring A mode: stirring speed 1200 rpm / min, stirring time 6 min; set B mode: 800 rpm / min, stirring time 4 min, vacuum degree 0.05 MPa; put all components into the cup, put into the star-shaped stirrer with set mode, select A mode stirring 3 times, then B mode stirring 1 time, the UV-LED and moisture dual-curing three-protection paint can be prepared.

[0088] The difference between Example 2 and Comparative Examples 1-3 and Example 1 is only that some components or amounts are different, the components and amounts of Example 1-2 and Comparative Examples 1-3 are shown in Table 1.

[0089] Table 1

[0090]

[0091] " / " in Table 1 means that the substance is not added.

[0092] Then test the performance of the three-protection paint prepared in the above examples and comparative examples, and the test method is as follows:

[0093] Viscosity: rotary viscometer, DVII 2# / 50 rpm 25℃ test three times to get average value;

[0094] Tack-free: scrape 200μm film on flat PCB board, use 365nm UV-LED lamp to cure, curing energy 5000mj / cm 2 , within 30 seconds after curing, observe whether there is fingerprint mark by touch;

[0095] Pure moisture curing time: scrape 200μm film on flat PCB board, place in 25±2℃, 50±10% relative humidity and light-proof environment, observe and record the film forming time;

[0096] Adhesion test: scrape 200μm film on flat PCB board, use 365nm UV-LED lamp to cure, curing energy 5000mj / cm 2 , then place in 25±2℃, 50±10% relative humidity and moisture curing for 7 days, test with 3M tape hatch method;

[0097] Elongation at break, bulk strength: film with 100mm*100mm*5mm mold, use 365nm UV-LED lamp to cure, curing energy 5000mj / cm 2Then, place it in 25±2℃, 50±10% relative humidity for 7 days, and then test it.

[0098] Dielectric strength: film was prepared by using 100mm*100mm*5mm mold, cured by 365nm UV-LED lamp, and the curing energy was 5000mj / cm 2 Then, place it in 25±2℃, 50±10% relative humidity for 7 days, and then test it.

[0099] Cold and hot impact (-40 to 85℃): PCB material with components, glue thickness of 150μm±20μm, 365nm UV-LED curing method, and the curing energy was 5000mj / cm 2 After placing it in 25±2℃, 50±10% relative humidity for 7 days, observe whether the glue film is delaminated, cracked, yellowed, blistered, etc. after 1000h of cold and hot impact.

[0100] High temperature and high humidity resistance (85℃, 85% relative humidity): PCB panel with components, glue thickness of 150μm±20μm, 365nm UV-LED lamp, and the curing energy was 5000mj / cm 2 After placing it in 25±2℃, 50±10% relative humidity for 7 days, observe whether the glue film is delaminated, cracked, yellowed, blistered, etc. after 1000h of high temperature and high humidity.

[0101] The test results are shown in Table 2 below, and the effect data of commercially available 7993 three-proofing paint are also given in Table 2.

[0102] Table 2

[0103]

[0104] From the results of Table 2 above, it can be seen that the UV-LED and moisture dual-curing three-proofing paint prepared by using polyurethane acrylic prepolymer A, acrylic modified isocyanate as the resin, and suitable active diluent and additives solves the problem of oxygen inhibition of traditional UV three-proofing paint in UV-LED curing, and has excellent aging performance such as cold and hot impact resistance, high temperature and high humidity resistance, etc.

[0105] From Example 1 and Comparative Examples 1-3, it can also be seen that the selection of raw materials in the preparation of polyurethane acrylic prepolymer will affect the performance of polyurethane acrylic prepolymer, and further affect the performance of the finally prepared three-proofing paint.

Claims

1. A UV-LED and moisture dual-curing three-layer paint, characterized by, The UV-LED and moisture dual-curing three-protection paint comprises, by weight fraction, 8-35 parts of polyurethane acrylate prepolymer, 8-35 parts of acrylate modified isocyanate prepolymer, 0.5-12 parts of photoinitiator and 20-70 parts of auxiliary agent; The polyurethane acrylate prepolymer contains urethane groups and acrylate double bonds, and wherein the NCO content is 0.1 0.5%; The raw materials for preparing the polyurethane acrylate prepolymer comprise difunctional polyester polyol, difunctional isocyanate monomer and hydroxyl acrylate monomer; the difunctional polyester polyol is polycarbonate polyol; said bifunctional isocyanate monomer is selected from isophorone diisocyanate IPDI, cyclohexane dimethylene diisocyanate HXDI or 4,4' at least one of diisocyanate dicyclohexylmethane HMDI; The preparation process of the acrylate modified isocyanate prepolymer comprises the following steps: The multifunctional isocyanate monomer, antioxidant and polymerization inhibitor are mixed, stirred and heated, then the hydroxyl acrylate monomer is added, and reaction is carried out to obtain the acrylate modified isocyanate prepolymer.

2. The UV-LED and moisture dual-curing three-layer paint according to claim 1, characterized by, The auxiliary agent comprises at least one of active diluent, coupling agent, leveling agent, defoaming agent, water removing agent and fluorescent agent.

3. The UV-LED and moisture dual-curing three-layer protective paint according to claim 1, characterized in that, The photoinitiator is selected from at least one of 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxy-cyclohexyl-phenylmethanone, 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide, 2,4,6-trimethylbenzoyl phenyl phosphonic acid ethyl ester, methyl benzoylformate, benzophenone.

4. The UV-LED and moisture dual-cured three-layer paint according to claim 2, characterized by, The active diluent is selected from at least one of isobornyl acrylate, tetrahydrofurfuryl acrylate, 4-tert-butylcyclohexyl acrylate, acryloyl morpholine, lauryl acrylate, bicyclo-pentenyl acrylate, 2-phenoxyethyl acrylate, ethoxylated tetrahydrofurfuryl acrylate, propoxylated tetrahydrofurfuryl acrylate, cyclotrimethylolpropane formal acrylate, isobornyl methacrylate, tetrahydrofurfuryl methacrylate, tripropylene glycol diacrylate, polyethylene glycol diacrylate.

5. The UV-LED and moisture dual-cured, triple prevention paint according to claim 2, characterized by, The auxiliary agent comprises active diluent, coupling agent, leveling agent, defoaming agent, water removing agent and fluorescent agent, and the UV-LED and moisture dual-curing three-protection paint comprises the following components by weight fraction: polyurethane acrylate prepolymer 10-30 parts acrylate modified isocyanate prepolymer 10-30 parts photoinitiator 1-10 parts active diluent 30-50 parts coupling agent 1-5 parts leveling agent 1-5 parts defoaming agent 0.01-2 parts water removing agent 0.05-2 parts fluorescent agent 0.001-1 parts.

6. The method of producing a UV-LED and moisture dual-cured three-antireflection coating according to any one of claims 1 to 5, characterized in that, comprises the following steps: The components are mixed to obtain the UV-LED and moisture dual-curing three-protection paint.

7. The production method according to claim 6, characterized by, The raw materials for preparing the polyurethane acrylate prepolymer further comprise active diluent, antioxidant, polymerization inhibitor and catalyst, and the preparation process of the polyurethane acrylate prepolymer comprises the following steps: The difunctional polyester polyol is subjected to dehydration treatment, cooled, then the active diluent, antioxidant and polymerization inhibitor are added, stirred and mixed, then the difunctional isocyanate monomer is added, stirred, heated, reacted, then the catalyst is added for continuous reaction, cooled after reaction, the hydroxyl acrylate monomer is added, and continuous reaction is carried out to obtain the polyurethane acrylate prepolymer.

8. Application of the UV-LED and moisture dual-curing three-protection paint according to any one of claims 1-5 in electronic products.

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