UV finish paint capable of being matched with thermosetting electroplating primer and application of UV finish paint

Abstract

The invention relates to the technical field of photocureable coatings, in particular to a UV finish paint capable of being matched with a thermosetting electroplating primer and application of the UV finish paint. The light-cured coating comprises the following components in parts by weight: 10-20 parts of thermoplastic acrylic resin, 1-5 parts of polyurethane acrylate, 5-10 parts of modified epoxy resin, 10-20 parts of an acrylate monomer, 1-4 parts of a photoinitiator, 0.1-1 part of phosphate, 0.1-1 part of a surface additive and 40-60 parts of a solvent. The thermoplastic acrylic resin comprises first thermoplastic acrylic resin and second thermoplastic acrylic resin, and by limiting the compounding ratio and viscosity of the first thermoplastic acrylic resin and the second thermoplastic acrylic resin, the overall leveling property of the system can be synergistically adjusted, and meanwhile the hardness and adhesive force of a paint film are guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of light-cured coatings, in particular to a UV topcoat matched with thermosetting electroplating primer and application thereof. BACKGROUND

[0002] In large-area lamp manufacturing, the coating process needs to meet both decorative and functional requirements: thermosetting electroplating primer has strong adaptability to complex structures, can form a uniform plating layer and improve the adhesion of the substrate, but its high energy consumption and long production cycle restrict the efficiency improvement; UV curing topcoat has the advantages of fast curing and high gloss, but in practical application, it faces three major technical bottlenecks: first, the limited UV light penetration easily leads to incomplete curing in energy blind areas such as lamp grooves and corners, resulting in film haze or re-sticking; second, the interfacial tension between the UV topcoat and the thermosetting electroplating primer is not matched, and the smooth surface of the plating layer leads to insufficient adhesion; third, the poor leveling performance during large-area spraying easily causes orange peel or pinhole defects due to the imbalance between solvent evaporation speed and curing speed. Therefore, developing a UV topcoat specially matched with thermosetting electroplating primer, which has low energy consumption, high adhesion and good leveling performance, has become a key technical requirement in the field of lamp coating.

[0003] Currently, the matching scheme of thermosetting primer and UV topcoat has obvious limitations: the thermosetting system (Chinese invention patent application CN118638457A) improves curing uniformity but sacrifices efficiency; the UV topcoat formula (Chinese invention patent application CN105176375A) optimizes single performance and does not solve the plating layer compatibility problem. SUMMARY

[0004] The present application provides a UV topcoat matched with thermosetting electroplating primer, by weight, the components include: 10-20 parts of thermoplastic acrylic resin, 1-5 parts of polyurethane acrylate, 5-10 parts of modified epoxy resin, 10-20 parts of acrylate monomer, 1-4 parts of photoinitiator, 0.1-1 part of phosphate, 0.1-1 part of surface additive, and 40-60 parts of solvent.

[0005] The viscosity of the thermoplastic acrylic resin at 25℃ is 3000-7000cps.

[0006] The thermoplastic acrylic resin includes a first thermoplastic acrylic resin and a second thermoplastic acrylic resin, and the weight ratio of the first thermoplastic acrylic resin to the second thermoplastic acrylic resin is (2-10):1.

[0007] Optionally, the weight ratio of the first thermoplastic acrylic resin to the second thermoplastic acrylic resin is (5-10):1.

[0008] The thermoplastic acrylic resin comprises a first thermoplastic acrylic resin and a second thermoplastic acrylic resin. By limiting the compounding ratio of the two and their viscosity, the overall leveling property of the system can be synergistically adjusted, while ensuring the hardness and adhesion of the paint film. The first resin with low viscosity can reduce the initial viscosity of the system, promote the flow spreading of the paint before curing, optimize the leveling property, and reduce defects such as orange peel caused by high viscosity. The second resin with higher viscosity can provide moderate cohesion to avoid sagging of the paint due to excessive flow, and its high molecular chain density can enhance the structural support of the paint film. The two work together, the good wetting property of the first resin helps to improve the interfacial adhesion to the plated layer of the thermosetting electroplating primer, and the second resin enhances the rigidity of the paint film to ensure the hardness through intermolecular forces, and a specific ratio (2-10):1 can balance the effects of the two in leveling promotion and structural support, adhesion improvement and hardness enhancement, avoiding poor leveling, insufficient hardness or decreased adhesion caused by improper viscosity of a single resin.

[0009] Optionally, the first thermoplastic acrylic resin has a viscosity of 3000-6000 cps at 25°C, and is purchased from Shaoguan City Kerui High Polymer Material Co., Ltd., KR1901; the second thermoplastic acrylic resin has a viscosity of 6000-7000 cps at 25°C, and is purchased from Guangdong Bote New Material Co., Ltd., BT1070.

[0010] The photoinitiator comprises alkyl phenone and acyl phosphine oxide, and the weight ratio of the alkyl phenone and the acyl phosphine oxide is (5-15):1.

[0011] Optionally, the weight ratio of the alkyl phenone and the acyl phosphine oxide is (7-12):1.

[0012] The alkyl phenone comprises α-hydroxy alkyl phenone.

[0013] The α-hydroxy alkyl phenone is selected from at least one of the following: JRCure 1104, photoinitiator 1173, photoinitiator 184, photoinitiator 2959, methyl benzoylformate.

[0014] Optionally, the α-hydroxy alkyl phenone is selected from JRCure 1104 of Tianjin Jiuri New Material Co., Ltd.

[0015] The acyl phosphine oxide comprises arylacyl phosphine oxide and bisbenzoyl phenyl phosphine oxide, and the weight ratio of the arylacyl phosphine oxide and the bisbenzoyl phenyl phosphine oxide is (2-6):1.

[0016] Optionally, the weight ratio of the arylacyl phosphine oxide and the bisbenzoyl phenyl phosphine oxide is (2-4):1.

[0017] Optionally, the arylacylphosphine oxide is selected from Tianjin Jiuri New Material Co., Ltd., JRCure1108.

[0018] Optionally, the bisbenzoylphenylphosphine oxide is selected from Tianjin Jiuri New Material Co., Ltd., JRCure1109.

[0019] The modified epoxy resin comprises a di-functional modified epoxy acrylate resin.

[0020] Optionally, the modified epoxy resin is purchased from Wuxi Wusanhua Synthetic Technology Co., Ltd., HY555.

[0021] The surface agent comprises a silicone leveling agent.

[0022] Optionally, the silicone leveling agent comprises a polyether modified dimethyl polysiloxane, which is selected from Jiashuo Fluorine Silicon Material (Hangzhou) Co., Ltd., L-3118.

[0023] The functionality of the polyurethane acrylate is 4-6.

[0024] Optionally, the polyurethane acrylate is selected from Jiangsu Sanmu Chemical Co., Ltd., 6621.

[0025] The acrylate monomer comprises a mono-functional acrylate monomer and a tri-functional acrylate monomer.

[0026] The weight ratio of the mono-functional acrylate monomer and the tri-functional acrylate monomer is 1:(0.5-2).

[0027] Optionally, the weight ratio of the mono-functional acrylate monomer and the tri-functional acrylate monomer is 1:(0.8-1.2).

[0028] Optionally, the mono-functional acrylate monomer comprises at least one of isobornyl acrylate, isobornyl methacrylate, hydroxyethyl methacrylate, butyl acrylate, isooctyl acrylate, cyclohexyl acrylate, 2-phenoxyethyl acrylate, and lauryl acrylate.

[0029] Optionally, the tri-functional acrylate monomer comprises at least one of trimethylolpropane triacrylate, pentaerythritol triacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane triacrylate, tris(2-hydroxyethyl) isocyanurate triacrylate.

[0030] Optionally, the mono-functional acrylate monomer is purchased from Sanyi Fanda Technology (Guangdong) Co., Ltd., hydroxyethyl methacrylate, and the tri-functional acrylate monomer is purchased from Jiangsu Sanmu Chemical Co., Ltd., pentaerythritol triacrylate.

[0031] The solvent includes at least one of ethyl acetate, butyl acetate, ethyl acetate, n-propyl acetate, methyl acetate, and n-butyl acetate.

[0032] Optionally, the solvent includes ethyl acetate and butyl acetate.

[0033] The second aspect of the present application provides an application of a UV topcoat matched with a thermosetting electroplating primer, matched with a thermosetting electroplating primer, and applied to a lamp product with irregular appearance.

[0034] Beneficial effects

[0035] 1. The thermoplastic acrylic resin includes a first thermoplastic acrylic resin and a second thermoplastic acrylic resin, and by limiting the compounding ratio of the two and their viscosities, the overall leveling of the system can be synergistically adjusted, while ensuring the hardness and adhesion of the paint film.

[0036] 2. The photoinitiator includes alkyl phenone and acyl phosphine oxide, and the weight ratio of the alkyl phenone and the acyl phosphine oxide is (5-15): 1. The two can synergistically improve the penetration of UV light to the energy blind area of the lamp groove, corner, etc., and avoid fogging or sticking caused by incomplete curing.

[0037] 3. The modified epoxy resin includes a di-functional modified epoxy acrylate resin, which can enhance the interfacial compatibility of the topcoat and the plated layer of the thermosetting electroplating primer, improve the interlayer adhesion, and make the adhesion of the plated layer of the primer reach 5B.

[0038] 4. The surface additive includes an organic silicon leveling agent, which can optimize the leveling during large-area spraying, reduce defects such as orange peel and pinholes, and at the same time improve the surface smoothness and gloss.

[0039] 5. The acrylate monomer includes a mono-functional acrylate monomer and a tri-functional acrylate monomer, and the weight ratio of the mono-functional acrylate monomer and the tri-functional acrylate monomer is 1:(0.5-2), which can synergistically balance the flexibility and hardness of the paint film, ensure the curing efficiency while avoiding brittleness. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 The surface morphology of the lamp before processing in Example 1

[0041] Figure 2 The surface morphology of the lamp after processing in Example 1

[0042] Figure 3 The color addition (blue color concentrate) effect diagram, the left picture is Example 1, and the right picture is Comparative Example 1.

[0043] Figure 4 The adhesion test effect diagram of Example 1

[0044] Figure 5 The adhesion test effect diagram of Comparative Example 6.

[0045] Figure 6 The adhesion test effect diagram of Comparative Example 8.

[0046] Figure 7 The physical diagram after curing, the left picture is Example 1, and the right picture is Comparative Example 3.

[0047] Figure 8 The physical diagram after curing, the left picture is Example 1, and the right picture is Comparative Example 4. DETAILED DESCRIPTION

[0048] Example 1, Comparative Examples 1-10

[0049] A UV topcoat matched with a thermosetting electroplating primer, the components are shown in Table 1 by weight parts, wherein the blank in the table indicates no addition:

[0050] Table 1

[0051]

[0052]

[0053] The viscosity of the first thermoplastic acrylic resin at 25℃ is 3000-6000cps, purchased from Shaoguan City Kerui High Polymer Material Co., Ltd., KR1901; the viscosity of the second thermoplastic acrylic resin at 25℃ is 6000-7000cps, purchased from Guangdong Bote New Material Co., Ltd., BT1070.

[0054] The α-hydroxyalkyl phenone is purchased from Tianjin Jiuri New Material Co., Ltd., JRCure 1104.

[0055] The arylacyl phosphine oxide is purchased from Tianjin Jiuri New Material Co., Ltd., JRCure 1108.

[0056] The bis-benzoyl phenyl phosphine oxide is purchased from Tianjin Jiuri New Material Co., Ltd., JRCure 1109.

[0057] The surface aid L-3118 is a silicone leveling agent composed of polyether modified dimethyl polysiloxane, purchased from Jiasuo Fluorine Silicon Material (Hangzhou) Co., Ltd.; the surface aid BYK371 is a silicone leveling agent composed of polyester modified dimethyl polysiloxane, purchased from Jiangmen City Dongyang Chemical Co., Ltd.; the surface aid LA533 is a modified acrylic leveling agent, purchased from Foshan Tegoe Polymer Technology Co., Ltd.

[0058] The polyurethane acrylate is selected from Jiangsu Sanmu Chemical Co., Ltd., 6621.

[0059] The monofunctional acrylate monomers were purchased from Sanyi Fangda Technology (Guangdong) Co., Ltd., and the trifunctional acrylate monomers were purchased from Jiangsu Sanmu Chemical Co., Ltd., and the pentaerythritol triacrylate was purchased from Jiangsu Sanmu Chemical Co., Ltd.

[0060] The modified epoxy resin HY555 was purchased from Wuxi Wusan Synthetic Technology Co., Ltd., the modified epoxy resin HY554 was purchased from Guangdong Haohui New Materials Co., Ltd., and the modified epoxy resin HY557 was purchased from Guangdong Haohui New Materials Co., Ltd.

[0061] The preparation method of the topcoat is as follows: the components are mixed and dispersed evenly under light-protected conditions.

[0062] Performance testing methods and data

[0063] The topcoat was prepared according to the examples and comparative formulations, first on the lamp material ( Figure 1 The surface is coated with a thermosetting primer (Bizhan 563), baked at 60°C for 4 hours, then electroplated with an aluminum film, and finally sprayed with a topcoat (average 10 micrometers). It is first irradiated at 60°C for 3 minutes, then subjected to UV irradiation (the light intensity of the topcoat in Examples 1 and Comparative Examples 1-4 is 300 mJ / cm²). 2 The light intensity of the topcoat in Comparative Examples 5-7 was 600 mJ / cm². 2 The light intensity of the topcoat in Comparative Examples 8-10 was 800 mJ / cm². 2 The lamp is cured to obtain the finished lamp. Figure 2 Perform the following tests.

[0064] 1. Hardness: GB / T 6739-96

[0065] 2. Primer coating adhesion: GB / T 9286, such as Figures 4-6 As shown in Figures 8 and 9, the topcoat of this invention exhibits excellent adhesion, such as... Figure 3 As shown, the coloring effect of the topcoat in the embodiment of the present invention is excellent.

[0066] 3. Surface condition: smoothness, whether it is matte, and gloss. For example... Figure 7 As shown, the topcoat in this embodiment of the invention has a mirror effect.

[0067] The test results are shown in Table 2, where “-” indicates that no test was performed.

[0068] Table 2

[0069]

[0070]

Claims

1. A UV topcoat that can be used with a thermosetting electroplating primer, characterized in that, By weight, the components include: 10-20 parts thermoplastic acrylic resin, 1-5 parts polyurethane acrylate, 5-10 parts modified epoxy resin, 10-20 parts acrylate monomer, 1-4 parts photoinitiator, 0.1-1 part phosphate ester, 0.1-1 part surface additives, and 40-60 parts solvent.

2. The UV topcoat compatible with thermosetting electroplating primer according to claim 1, characterized in that, The thermoplastic acrylic resin has a viscosity of 3000-7000 cps at 25°C.

3. The UV topcoat compatible with thermosetting electroplating primer according to claim 2, characterized in that, The thermoplastic acrylic resin includes a first thermoplastic acrylic resin and a second thermoplastic acrylic resin, wherein the weight ratio of the first thermoplastic acrylic resin and the second thermoplastic acrylic resin is (2-10):1, the viscosity of the first thermoplastic acrylic resin at 25°C is 3000-6000 cps, and the viscosity of the second thermoplastic acrylic resin at 25°C is 6000-7000 cps.

4. The UV topcoat compatible with thermosetting electroplating primer according to claim 1, characterized in that, The photoinitiator includes alkyl phenyl ketones and acyl phosphorus oxides, wherein the weight ratio of the alkyl phenyl ketones to the acyl phosphorus oxides is (5-15):

1.

5. The UV topcoat compatible with thermosetting electroplating primer according to claim 4, characterized in that, The acylphosphine oxides include arylphosphine oxides and bisbenzoylphenylphosphine oxides, wherein the weight ratio of the arylphosphine oxides to the bisbenzoylphenylphosphine oxides is (2-6):

1.

6. The UV topcoat compatible with thermosetting electroplating primer according to claim 1, characterized in that, The modified epoxy resin includes difunctional modified epoxy acrylate resin.

7. The UV topcoat compatible with thermosetting electroplating primer according to claim 6, characterized in that, The surface additives include silicone leveling agents.

8. The UV topcoat compatible with a thermosetting electroplating primer according to claim 7, characterized in that, The functionality of the polyurethane acrylate is 4-6.

9. The UV topcoat compatible with a thermosetting electroplating primer according to claim 8, characterized in that, The acrylate monomers include monofunctional acrylate monomers and trifunctional acrylate monomers, and the weight ratio of the monofunctional acrylate monomers to the trifunctional acrylate monomers is 1:(0.5-2).

10. An application of a UV topcoat compatible with a thermosetting electroplating primer according to any one of claims 1-9, characterized in that, When used with a thermosetting electroplating primer, it can be applied to lighting products with irregular shapes.

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