A high-adhesion UV LED coating composition and its preparation method

Abstract

The application discloses a high-adhesion UV LED coating composition and a preparation method thereof, and comprises the following raw materials and weight parts: a composite oligomer 50-70 parts, a composite active diluent 90-120 parts, a composite photoinitiator 1.5-2.5 parts, a composite adhesion promoter 0.8-1.8 parts, inorganic fillers 5-15 parts, a fluorine-modified acrylate leveling agent 0.6-1.5 parts and a light stabilizer 0.1-0.7 parts. The UV LED coating composition has good combination with untreated low-polarity plastics, smooth metal surfaces and the like, has high adhesion, and is not easy to peel off after external force.

Description

Technical Field

[0001] This invention relates to a high-adhesion UV LED coating composition and its preparation method, belonging to the field of UV LED coating technology. Background Technology

[0002] In recent years, UV LED coatings have emerged as a new type of curable coating. UV LEDs use high-energy ultraviolet light-emitting diodes as the light source, offering advantages such as high efficiency, environmental friendliness, long lifespan, and energy saving, making them applicable in the automotive, electronics, and packaging industries. The materials used in automobiles and electronics include plastics, metals, and composite materials, and their shapes are often complex. Existing UV LED coatings often incorporate inorganic fillers to enhance color or abrasion resistance, which can affect their adhesion to certain substrates. Furthermore, existing UV LED coatings tend to become brittle and lack flexibility after curing, making them prone to cracking and peeling under impact or bending. Such UV LED coatings result in brittle films with poor adhesion. Summary of the Invention

[0003] At least to address one of the problems existing in the prior art, the present invention provides a high-adhesion UV LED coating composition and its preparation method, which enables the UV LED coating to have good bonding with untreated low-polarity plastics, smooth metal surfaces, etc., and has high adhesion and is not easy to peel off after being subjected to external force.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a high-adhesion UV LED coating composition, comprising the following raw materials and their weight parts: 50-70 parts of composite oligomer, 90-120 parts of composite reactive diluent, 1.5-2.5 parts of composite photoinitiator, 0.8-1.8 parts of composite adhesion promoter, 5-15 parts of inorganic filler, 0.6-1.5 parts of fluorinated acrylate leveling agent, and 0.1-0.7 parts of light stabilizer;

[0005] The composite oligomer is composed of polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon-modified polyurethane acrylate, and 2-(perfluorohexyl)ethyl methacrylate.

[0006] The composite photoinitiator includes at least two of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and ferrocene salt photoinitiators;

[0007] The composite reactive diluent includes at least two of the following: bifunctional acrylates, β-carboxyethyl acrylates and N-vinylcaprolactam, and β-hydroxyethyl methacrylate.

[0008] The composite adhesion promoter is composed of a phosphate ester coupling agent and a silane coupling agent.

[0009] Preferably, the preparation process of the polysiloxane-epoxy-acrylate is as follows:

[0010] Step 1: First, dissolve methacrylic acid, triethylamine, and p-hydroxyanisole in acetone to obtain a premixed solution;

[0011] Step 2: Dissolve the bi-terminated epoxy polysiloxane in acetone solvent. Under a nitrogen atmosphere, add the premixed solution dropwise to react. After the addition is complete, make the molar ratio of bi-terminated epoxy polysiloxane to methacrylic acid 1:2.05~2.15, the triethylamine 0.8~1.1% of the mass of bi-terminated epoxy polysiloxane, and the p-hydroxyanisole 0.01~0.08% of the mass of bi-terminated epoxy polysiloxane. Continue the reaction until the reaction is complete. Remove the solvent, catalyst, etc., wash and dry to obtain polysiloxane-epoxy-acrylate.

[0012] Preferably, the preparation process of the hyperbranched organosilicon-modified polyurethane acrylate is as follows:

[0013] (1) First, dissolve isophorone diisocyanate in acetone solvent, add bismuth acetylacetonate, the bismuth acetylacetonate is 3-5% of the mass of isophorone diisocyanate, heat to 60-65℃, add hydroxyalkyl silicone oil dropwise until the molar ratio of NCO:OH of the added isophorone diisocyanate to hydroxyalkyl silicone oil is 2:1, react for 30-40 min, add 2,2-dimethylolpropionic acid, the molar ratio of 2,2-dimethylolpropionic acid to isophorone diisocyanate is 1:2, continue to react for 50-60 min, add hydroxyl-terminated hyperbranched polyester, the molar ratio of hydroxyl-terminated hyperbranched polyester to isophorone diisocyanate is 1:12, continue to react until NCO reacts completely, and obtain reactant I containing hydroxyl-terminated groups;

[0014] (2) First, dissolve isophorone diisocyanate in acetone solvent, add bismuth acetylacetonate, the bismuth acetylacetonate being 1~2% of the mass of isophorone diisocyanate, heat to 40~45℃, add 2-hydroxyethyl acrylate dropwise until the molar ratio of NCO:OH of the added isophorone diisocyanate to 2-hydroxyethyl acrylate is 2:1, react for 40~50min, and obtain reactant II;

[0015] (3) Mix reactant I and reactant II with isophorone diisocyanate added in step (1) and isophorone diisocyanate added in step (2) in a molar ratio of 2:1, heat to 60~65℃ to react, so that NCO reaction is complete, add triethylamine, maintain for 30~40min, remove solvent, catalyst, etc., wash and dry to obtain hyperbranched organosilicon modified polyurethane acrylate.

[0016] Preferably, the composite oligomer is composed of polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon-modified polyurethane acrylate, and 2-(perfluorohexyl)ethyl methacrylate in a mass ratio of 6~8:3~5:2~3:1.5~2.5.

[0017] The composite adhesion promoter is composed of phosphate ester coupling agent and silane coupling agent in a mass ratio of 2~3:1.

[0018] Preferably, the composite photoinitiator is composed of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and ferrocene salt photoinitiator.

[0019] Preferably, the composite photoinitiator is composed of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and ferrocene salt photoinitiator in a mass ratio of 3.5~4.5:2~3:0.5~1.5.

[0020] Preferably, the ferrocene salt photoinitiator is cumeneferrocene hexafluorophosphate.

[0021] Preferably, the composite reactive diluent is composed of β-carboxyethyl acrylate, N-vinylcaprolactam and β-hydroxyethyl methacrylate.

[0022] Preferably, the composite reactive diluent is composed of β-carboxyethyl acrylate, N-vinylcaprolactam and β-hydroxyethyl methacrylate in a mass ratio of 5:2~3:1~2.

[0023] Preferably, the composite reactive diluent is composed of β-carboxyethyl acrylate, bifunctional acrylates, and β-hydroxyethyl methacrylate.

[0024] Preferably, the composite reactive diluent is composed of β-carboxyethyl acrylate, bifunctional acrylates and β-hydroxyethyl methacrylate in a mass ratio of 5:3~4:1~2.

[0025] Preferably, the bifunctional acrylate is one or more of 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, tripropylene glycol diacrylate, and polyethylene glycol diacrylate.

[0026] Preferably, the phosphate coupling agent is one of 2-hydroxyethyl methacrylate phosphate or methacrylate esterified phosphate; more preferably, it is 2-hydroxyethyl methacrylate phosphate.

[0027] Preferably, the silane coupling agent is one of γ-glycidoxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, or N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

[0028] Preferably, the inorganic filler includes one or more of pigments, silica, alumina powder, or ceramic powder.

[0029] Preferably, the fluorinated acrylate leveling agent is one of FLUORO-ACR3800 leveling agent, ASK-192 leveling agent, MONENG®-S1154 leveling agent, or MOK-2041 leveling agent.

[0030] Preferably, the light stabilizer is composed of a hindered amine light stabilizer and an ultraviolet absorber.

[0031] Preferably, the hindered amine light stabilizer is light stabilizer 770.

[0032] Preferably, the ultraviolet absorber is ultraviolet absorber UV-327.

[0033] The present invention also provides a method for preparing a high-adhesion UV LED coating composition, comprising the following steps: first, premixing an inorganic filler with a composite adhesion promoter, then adding a composite oligomer, a composite reactive diluent, a composite photoinitiator, a fluorinated acrylate leveling agent and a light stabilizer for mixing treatment to obtain a high-adhesion UV LED coating composition.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) The UV LED coating composition of the present invention uses a composite system of polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon-modified polyurethane acrylate, and 2-(perfluorohexyl)ethyl methacrylate as the matrix oligomer resin, which improves UV performance. The LED coating composition exhibits improved adhesion and mechanical properties on various substrates such as plastics, metals, and composite materials, which helps reduce the risk of cracking and peeling of the base resin and provides excellent anti-yellowing performance. 2) This invention uses a composite system of at least two of bifunctional acrylates, β-carboxyethyl acrylate, and N-vinylcaprolactam, along with methacrylate-β-hydroxyethyl ester, as a diluent and tackifier, further synergistically promoting the adhesion of the base resin to the substrate and improving its toughness, thus enhancing its applicability to complex substrate structures. 3) This invention uses a composite system of at least two of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and ferrocene salt photoinitiator as a photoinitiator, effectively improving the photoinitiation effect and achieving effective surface and deep curing of the UV LED coating composition, while also improving curing efficiency. Furthermore, the synergistic effect of the three components significantly enhances UV performance. The adhesion and toughness of the LED coating composition are improved, and the anti-yellowing performance is further enhanced; 4) The present invention uses a composite system of phosphate ester coupling agent and silane coupling agent as an accelerator, which is beneficial to improve the interfacial strength between inorganic filler and matrix oligomer resin, while also promoting the improvement of the adhesion and mechanical strength of matrix oligomer resin; 5) The present invention uses fluorinated acrylate leveling agent, which is more conducive to enhancing the wettability and corrosion resistance of UV LED coating composition to substrates such as plastics, metals and composite materials, improving the adhesion of UV LED coating composition, and the coating film is more uniform and smooth, without local defects such as pores, bubbles, gaps, and shrinkage cavities. Detailed Implementation

[0035] The following is a clear and complete description of the technical solutions in the implementation of this invention. The described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents, instruments, or components used that do not specify the manufacturer are all conventional products that can be purchased commercially.

[0036] Preliminary Example 1: Preparation of Polysiloxane-Epoxy-Acrylic Ester

[0037] The preparation process of polysiloxane-epoxy-acrylate is as follows:

[0038] Step 1: First, dissolve methacrylic acid, triethylamine, and p-hydroxyanisole in acetone to obtain a premixed solution;

[0039] Step 2: Dissolve the bi-terminated epoxy polysiloxane in acetone solvent. Under a nitrogen atmosphere, add the premixed solution dropwise to react. After the addition is complete, make the molar ratio of bi-terminated epoxy polysiloxane to methacrylic acid 1:2.05~2.15, the triethylamine 0.8~1.1% of the mass of bi-terminated epoxy polysiloxane, and the p-hydroxyanisole 0.01~0.08% of the mass of bi-terminated epoxy polysiloxane. Continue the reaction until the reaction is complete. Remove the solvent, catalyst, etc., wash and dry to obtain polysiloxane-epoxy-acrylate.

[0040] Preliminary Example 2: Preparation of Hyperbranched Organosilicon-Modified Polyurethane Acrylate

[0041] The preparation process of hyperbranched organosilicon-modified polyurethane acrylate is as follows:

[0042] (1) First, dissolve isophorone diisocyanate in acetone solvent, add bismuth acetylacetonate, the bismuth acetylacetonate is 3-5% of the mass of isophorone diisocyanate, heat to 60-65℃, add hydroxyalkyl silicone oil dropwise until the molar ratio of NCO:OH of the added isophorone diisocyanate to hydroxyalkyl silicone oil is 2:1, react for 30-40 min, add 2,2-dimethylolpropionic acid, the molar ratio of 2,2-dimethylolpropionic acid to isophorone diisocyanate is 1:2, continue to react for 50-60 min, add hydroxyl-terminated hyperbranched polyester, the molar ratio of hydroxyl-terminated hyperbranched polyester to isophorone diisocyanate is 1:12, continue to react until NCO reacts completely, and obtain reactant I containing hydroxyl-terminated groups;

[0043] (2) First, dissolve isophorone diisocyanate in acetone solvent, add bismuth acetylacetonate, the bismuth acetylacetonate being 1~2% of the mass of isophorone diisocyanate, heat to 40~45℃, add 2-hydroxyethyl acrylate dropwise until the molar ratio of NCO:OH of the added isophorone diisocyanate to 2-hydroxyethyl acrylate is 2:1, react for 40~50min, and obtain reactant II;

[0044] (3) Mix reactant I and reactant II with isophorone diisocyanate added in step (1) and isophorone diisocyanate added in step (2) in a molar ratio of 2:1, heat to 60~65℃ to react, so that NCO reaction is complete, add triethylamine, maintain for 30~40min, remove solvent, catalyst, etc., wash and dry to obtain hyperbranched organosilicon modified polyurethane acrylate.

[0045] Example 1

[0046] A high-adhesion UV LED coating composition comprises the following raw materials and their parts by weight: 50 parts of composite oligomer, 100 parts of composite reactive diluent, 2 parts of composite photoinitiator, 1.2 parts of composite adhesion promoter, 6 parts of nano silica, 4 parts of nano alumina powder, 0.6 parts of FLUORO-ACR3800 leveling agent, 0.1 parts of light stabilizer 770 and 0.1 parts of ultraviolet absorber UV-327;

[0047] In the composite oligomer: 20 parts polyurethane acrylate, 13.3 parts polysiloxane-epoxy-acrylate, 8.4 parts hyperbranched organosilicon-modified polyurethane acrylate and 8.3 parts 2-(perfluorohexyl)ethyl methacrylate (CAS No. 2144-53-8, the same below);

[0048] In the composite reactive diluent: 40.9 parts β-carboxyethyl acrylate, 18.2 parts tripropylene glycol diacrylate, 27.3 parts N-vinylcaprolactam and 13.6 parts β-hydroxyethyl methacrylate;

[0049] The composite photoinitiator contains: 1 part 1-hydroxycyclohexylphenyl ketone, 0.58 parts 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and 0.42 parts cumene ferrocene hexafluorophosphate;

[0050] In the composite adhesion promoter: 0.8 parts 2-hydroxyethyl methacrylate phosphate, 0.4 parts γ-glycidyl etheroxypropyltrimethoxysilane;

[0051] The preparation method of the UV LED coating composition is as follows: First, the above-mentioned nano silica, nano alumina powder, 2-hydroxyethyl methacrylate phosphate and γ-glycidyl etheroxypropyltrimethoxysilane are premixed at high speed. Then, polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon modified polyurethane acrylate, 2-(perfluorohexyl)ethyl methacrylate, β-carboxyethyl acrylate, tripropylene glycol diacrylate, N-vinylcaprolactam, β-hydroxyethyl methacrylate, 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, cumeneferrocene hexafluorophosphate, FLUORO-ACR3800 leveling agent, light stabilizer 770 and ultraviolet absorber UV-327 are mixed to form a high-adhesion UV LED coating composition.

[0052] Example 2

[0053] A high-adhesion UV LED coating composition comprises the following raw materials and their parts by weight: 70 parts of composite oligomer, 90 parts of composite reactive diluent, 1.5 parts of composite photoinitiator, 1.8 parts of composite adhesion promoter, 8 parts of nano silica, 0.8 parts of ASK-192 leveling agent, 0.3 parts of light stabilizer 770 and 0.2 parts of ultraviolet absorber UV-327;

[0054] In the composite oligomer: 36.2 parts polyurethane acrylate, 15.6 parts polysiloxane-epoxy-acrylate, 10.4 parts hyperbranched organosilicon-modified polyurethane acrylate and 7.8 parts 2-(perfluorohexyl)ethyl methacrylate;

[0055] The composite reactive diluent contains: 37.5 parts β-carboxyethyl acrylate, 22.5 parts polyethylene glycol diacrylate (CAS No. 26570-48-9), 22.5 parts N-vinylcaprolactam, and 7.5 parts β-hydroxyethyl methacrylate.

[0056] The composite photoinitiator contains: 0.75 parts of 1-hydroxycyclohexylphenyl ketone, 0.56 parts of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and 0.19 parts of cumeneferrocene hexafluorophosphate;

[0057] In the composite adhesion promoter: 1.35 parts 2-hydroxyethyl methacrylate phosphate, 1.45 parts γ-(methacryloyloxy)propyltrimethoxysilane;

[0058] The preparation method of the UV LED coating composition is as follows: First, the above-mentioned nano silica, 2-hydroxyethyl methacrylate phosphate and γ-(methacryloyloxy)propyltrimethoxysilane are premixed at high speed, and then polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon modified polyurethane acrylate, 2-(perfluorohexyl)ethyl methacrylate, β-carboxyethyl acrylate, polyethylene glycol diacrylate, N-vinylcaprolactam, β-hydroxyethyl methacrylate, 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, cumeneferrocene hexafluorophosphate, ASK-192 leveling agent, light stabilizer 770 and ultraviolet absorber UV-327 are mixed to form a high-adhesion UV LED coating composition.

[0059] Example 3

[0060] A high-adhesion UV LED coating composition comprises the following raw materials and their parts by weight: 60 parts of composite oligomer, 120 parts of composite reactive diluent, 2.5 parts of composite photoinitiator, 0.8 parts of composite adhesion promoter, 6 parts of nano silica, 8 parts of iron oxide red, 1.2 parts of MOK-2041 leveling agent, 0.4 parts of light stabilizer 770 and 0.3 parts of ultraviolet absorber UV-327.

[0061] In the composite oligomer: 26.6 parts polyurethane acrylate, 16.6 parts polysiloxane-epoxy-acrylate, 10 parts hyperbranched organosilicon-modified polyurethane acrylate and 6.8 parts 2-(perfluorohexyl)ethyl methacrylate;

[0062] In the composite reactive diluent: 48 parts β-carboxyethyl acrylate, 24 parts 1,6-hexanediol diacrylate, 32 parts N-vinylcaprolactam and 16 parts β-hydroxyethyl methacrylate;

[0063] In the composite photoinitiator: 1.5 parts 1-hydroxycyclohexylphenyl ketone, 0.83 parts 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and 0.17 parts cumeneferrocene hexafluorophosphate;

[0064] In the composite adhesion promoter: 0.58 parts of 2-hydroxyethyl methacrylate phosphate and 0.22 parts of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane;

[0065] The preparation method of the UV LED coating composition is as follows: First, the above-mentioned nano silica, iron oxide red, 2-hydroxyethyl methacrylate phosphate and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane are premixed at high speed. Then, polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon modified polyurethane acrylate, 2-(perfluorohexyl)ethyl methacrylate, β-carboxyethyl acrylate, 1,6-hexanediol diacrylate, N-vinylcaprolactam, β-hydroxyethyl methacrylate, 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, cumeneferrocene hexafluorophosphate, MOK-2041 leveling agent, light stabilizer 770 and ultraviolet absorber UV-327 are mixed to form a high-adhesion UV LED coating composition.

[0066] Example 4

[0067] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite photoinitiator: 1.5 parts of 1-hydroxycyclohexylphenyl ketone and 0.5 parts of cumeneferrocene hexafluorophosphate.

[0068] Example 5

[0069] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite photoinitiator: 1.4 parts of 1-hydroxycyclohexylphenyl ketone and 0.6 parts of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide.

[0070] Example 6

[0071] A high-adhesion UV LED coating composition and its preparation method differ from the examples in that: in the composite photoinitiator: 1.2 parts of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and 0.8 parts of cumeneferrocene hexafluorophosphate.

[0072] Example 7

[0073] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite reactive diluent: 55.5 parts of β-carboxyethyl acrylate, 27.8 parts of N-vinylcaprolactam and 16.7 parts of β-hydroxyethyl methacrylate.

[0074] Example 8

[0075] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite reactive diluent: 50 parts of β-carboxyethyl acrylate, 35 parts of tripropylene glycol diacrylate and 15 parts of β-hydroxyethyl methacrylate.

[0076] Comparative Example 1

[0077] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite oligomer: 20 parts polyurethane acrylate, 13.3 parts polysiloxane-epoxy-acrylate and 16.7 parts hyperbranched organosilicon-modified polyurethane acrylate.

[0078] Comparative Example 2

[0079] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite oligomer: 20 parts polyurethane acrylate, 13.3 parts polysiloxane-epoxy-acrylate and 16.7 parts 2-(perfluorohexyl)ethyl methacrylate.

[0080] Comparative Example 3

[0081] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite oligomer: 20 parts polyurethane acrylate, 14.7 parts hyperbranched organosilicon-modified polyurethane acrylate and 15.3 parts 2-(perfluorohexyl)ethyl methacrylate.

[0082] Comparative Example 4

[0083] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite oligomer: 20 parts epoxy acrylate resin, 13.3 parts polysiloxane-epoxy-acrylate, 8.4 parts hyperbranched organosilicon-modified polyurethane acrylate and 8.3 parts 2-(perfluorohexyl)ethyl methacrylate.

[0084] Comparative Example 5

[0085] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite reactive diluent: 76.4 parts of β-carboxyethyl acrylate and 13.6 parts of β-hydroxyethyl methacrylate.

[0086] Comparative Example 6

[0087] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite reactive diluent: 76.4 parts of tripropylene glycol diacrylate and 13.6 parts of β-hydroxyethyl methacrylate.

[0088] Comparative Example 7

[0089] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite reactive diluent: 76.4 parts of N-vinylcaprolactam and 13.6 parts of β-hydroxyethyl methacrylate.

[0090] Comparative Example 8

[0091] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite reactive diluent: 54.5 parts β-carboxyethyl acrylate, 18.2 parts tripropylene glycol diacrylate and 27.3 parts N-vinylcaprolactam.

[0092] Comparative Example 9

[0093] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite photoinitiator: 1 part 1-hydroxycyclohexylphenyl ketone, 0.58 parts ethyl 2,4,6-trimethylbenzoylphenylphosphonate and 0.42 parts cumeneferrocene hexafluorophosphate.

[0094] Comparative Example 10

[0095] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite photoinitiator: 1 part 1-hydroxycyclohexylphenyl ketone, 0.58 parts ethyl 2,4,6-trimethylbenzoylphenylphosphonate and 0.42 parts triarylthionium salt.

[0096] Comparative Example 11

[0097] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: in the composite photoinitiator: 1 part 2-hydroxy-2-methyl-1-phenylpropanone, 0.58 parts ethyl 2,4,6-trimethylbenzoylphenylphosphonate and 0.42 parts triarylthionium salt.

[0098] Comparative Example 12

[0099] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that 2-hydroxyethyl methacrylate phosphate is used instead of the composite adhesion promoter.

[0100] Comparative Example 13

[0101] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that γ-glycidyl etheroxypropyltrimethoxysilane is used instead of the composite adhesion promoter.

[0102] Comparative Example 14

[0103] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: acrylate leveling agent BYK-358N is used instead of FLUORO-ACR3800 leveling agent.

[0104] Comparative Example 15

[0105] A high-adhesion UV LED coating composition and its preparation method differ from Example 1 in that: organic modified polysiloxane acrylate leveling agent TegoRad 2100 is used instead of FLUORO-ACR3800 leveling agent.

[0106] Effect test

[0107] The UV LED coating compositions prepared in Examples 1-8 and Comparative Examples 1-16 were subjected to performance tests, and the test results are shown in Table 1.

[0108] Adhesion: According to GB / T 9286-2021 "Paints and Varnishes Cross-cut Test", the adhesion level of the paint film to plastic (ABS board) and metal (smooth aluminum board) is tested;

[0109] Flexibility: According to GB / T1731-2020 "Test Method for Flexibility of Paint Film and Putty Film", flexibility is expressed as the smallest shaft diameter (mm) that does not cause damage to the paint film.

[0110] Impact strength: According to GB / T1732-2020 "Test Method for Impact Resistance of Coating Film", the height (cm) of the coating film when a 1kg weight falls freely and causes cracking or peeling is detected, in order to determine its impact strength;

[0111] Hardness: The hardness rating of paint films on plastics (ABS board) and metals (smooth aluminum board) is tested according to GB / T 6739-2022 "Determination of Hardness of Paints and Varnishes by Pencil Method".

[0112] UV yellowing resistance: According to GB / T1865-2009 "Artificial weathering and artificial radiation exposure of paints and varnishes - filtered xenon arc radiation", the yellowing value (total color difference) ΔE of the paint film after 360 hours of UVA irradiation was tested.

[0113] Corrosion resistance: According to GB / T1763-1989 "Test Method for Chemical Resistance of Coating Film", the time (h) for defects such as peeling, blistering, and color changes of the coating film in 5% HCl solution and 5% NaOH solution is tested to determine its acid and alkali corrosion resistance.

[0114] Table 1 Performance of UV LED Coating Compositions

[0115]

[0116] As shown in the table above, the UV LED coating composition system of this invention, formed by the synergistic effect of the components, comprises a composite oligomer of polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon-modified polyurethane acrylate, and 2-(perfluorohexyl)ethyl methacrylate; a composite reactive diluent composed of at least two of bifunctional acrylates, β-carboxyethyl acrylate, and N-vinylcaprolactam, and β-hydroxyethyl methacrylate; a composite photoinitiator composed of at least two of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and ferrocene salt photoinitiators; a composite accelerator composed of phosphate coupling agent and silane coupling agent; and a fluorinated acrylate leveling agent. The crosslinking structure formed by the synergistic effect of the components has a strong crosslinking density and is not prone to shrinkage after curing. The LED coating composition exhibits high adhesion to various substrates such as plastics, metals, and composite materials, and possesses better mechanical properties, significantly reducing the risk of cracking and peeling of the base resin. It also exhibits excellent anti-yellowing and corrosion resistance. Furthermore, the UV LED coating film of this invention is more uniform and smooth, free from localized defects such as pores, bubbles, gaps, and shrinkage cavities. The UV LED coating composition of this invention is an excellent curing coating prepared from a special material containing polysiloxane, fluorocarbon, and other groups.

[0117] In summary, the UV LED coating of the present invention can bond well with untreated low-polarity plastics, smooth metal surfaces, etc., has high adhesion and mechanical properties, is not easy to peel off after being subjected to external force, and also has excellent anti-yellowing and corrosion resistance.

[0118] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit and essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0119] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A high-adhesion UV LED coating composition, characterized in that, It includes the following raw materials and their weight parts: 50-70 parts of composite oligomer, 90-120 parts of composite reactive diluent, 1.5-2.5 parts of composite photoinitiator, 0.8-1.8 parts of composite adhesion promoter, 5-15 parts of inorganic filler, 0.6-1.5 parts of fluorinated acrylate leveling agent, and 0.1-0.7 parts of light stabilizer; The composite oligomer is composed of polyurethane acrylate, polysiloxane-epoxy-acrylate, hyperbranched organosilicon-modified polyurethane acrylate, and 2-(perfluorohexyl)ethyl methacrylate in a mass ratio of 6~8:3~5:2~3:1.5~2.

5. The composite photoinitiator includes at least two of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and ferrocene salt photoinitiators; The composite reactive diluent includes at least two of the following: bifunctional acrylates, β-carboxyethyl acrylates and N-vinylcaprolactam, and β-hydroxyethyl methacrylate. The composite adhesion promoter is composed of phosphate ester coupling agent and silane coupling agent in a mass ratio of 2~3:

1.

2. The high-adhesion UV LED coating composition according to claim 1, characterized in that, The composite photoinitiator is composed of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and ferrocene salt photoinitiator in a mass ratio of 3.5~4.5:2~3:0.5~1.

5.

3. The high-adhesion UV LED coating composition according to claim 2, characterized in that, The ferrocene salt photoinitiator is cumeneferrocene hexafluorophosphate.

4. The high-adhesion UV LED coating composition according to claim 1, characterized in that, The composite reactive diluent is composed of β-carboxyethyl acrylate, N-vinylcaprolactam and β-hydroxyethyl methacrylate.

5. The high-adhesion UV LED coating composition according to claim 1, characterized in that, The composite reactive diluent is composed of β-carboxyethyl acrylate, bifunctional acrylates, and β-hydroxyethyl methacrylate.

6. A high-adhesion UV LED coating composition according to claim 1, 4, or 5, characterized in that, The bifunctional acrylates are one or more of 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, tripropylene glycol diacrylate, and polyethylene glycol diacrylate.

7. The high-adhesion UV LED coating composition according to claim 1, characterized in that, The fluorinated acrylate leveling agent is one of FLUORO-ACR3800 leveling agent, ASK-192 leveling agent, MONENG®-S1154 leveling agent, or MOK-2041 leveling agent.

8. The high-adhesion UV LED coating composition according to claim 1, characterized in that, The phosphate coupling agent is one of 2-hydroxyethyl methacrylate phosphate or methacrylated phosphate; The silane coupling agent is one of γ-glycidoxypropyltrimethoxysilane, γ-(methacryloyloxy)propyltrimethoxysilane, or N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

9. The high-adhesion UV LED coating composition according to claim 1, characterized in that, The light stabilizer is composed of a hindered amine light stabilizer and an ultraviolet absorber.

10. A method for preparing the high-adhesion UV LED coating composition according to claim 1, characterized in that, Includes the following steps: First, inorganic fillers and composite adhesion promoters are premixed, and then composite oligomers, composite reactive diluents, composite photoinitiators, fluorinated acrylate leveling agents and light stabilizers are added and mixed to obtain a high-adhesion UV LED coating composition.

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