An ultraviolet light-cured coating and a method for preparing the same

Abstract

The application provides an ultraviolet light curing paint and a preparation method thereof, and relates to the technical field of paint preparation. The ultraviolet light curing paint comprises the following raw materials in parts by mass: 30-45 parts of polyurethane acrylate, 5-15 parts of modified inorganic powder, 5-15 parts of active diluent, 1-5 parts of photoinitiator, and 2-5 parts of additive. The ultraviolet light curing paint prepared by the method has excellent pencil hardness and adhesion of the film formed after curing.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, and in particular to an ultraviolet-curable coating and its preparation method. Background Technology

[0002] Ultraviolet (UV) curing technology refers to a technique that allows monomers or polymers with added photoinitiators to react and rapidly transform into a solid state under UV light. It is a rapidly developing, energy-saving, and environmentally friendly emerging technology. Currently, UV curing technology has been widely adopted on various substrates, especially in the fields of wood, metal, plastics, leather, paper, electronics, and chemicals. Therefore, developing a UV-curable coating is of great significance to the development of UV curing technology. Summary of the Invention

[0003] Based on the technical problems existing in the background technology, the present invention proposes an ultraviolet curable coating and its preparation method.

[0004] The present invention proposes an ultraviolet curable coating comprising the following raw materials in parts by weight: 30-45 parts polyurethane acrylate, 5-15 parts modified inorganic powder, 5-15 parts reactive diluent, 1-5 parts photoinitiator, and 2-5 parts additives.

[0005] Preferably, the method for preparing the modified inorganic powder includes the following steps: mixing urea, talc, and silicon dioxide evenly and calcining to obtain a mixture; adding trimethoxysilane solution to the mixture, mixing evenly, and drying to obtain the modified inorganic powder.

[0006] More preferably, the mass ratio of urea, talc, and silica is (5-10):(0.5-2):(5-10).

[0007] More preferably, the calcination includes first heating to 100-200℃ at 2-3℃ / min and holding for 10-30min, then heating to 500-600℃ at 5-10℃ / min and holding for 3-6h.

[0008] More preferably, the mass fraction of the trimethoxysilane solution is 1-10 wt%.

[0009] Preferably, the reactive diluent is selected from one or more of trimethylolpropane trimethacrylate and acrylate.

[0010] Preferably, the photoinitiator comprises triethanolamine and 2-hydroxy-2-methyl-1-phenyl-1-propanone, wherein the mass ratio of triethanolamine to 2-hydroxy-2-methyl-1-phenyl-1-propanone is (0.1-0.5):1.

[0011] Preferably, the additives include defoamers and leveling agents.

[0012] This invention also proposes a method for preparing a UV-curable coating, comprising the following steps:

[0013] After ultrasonically dispersing modified silica and reactive diluent evenly, polyurethane acrylate, photoinitiator, and additives are added and mixed evenly to obtain a UV-curable coating.

[0014] The beneficial effects of this invention are as follows:

[0015] This invention proposes a UV-curable coating comprising polyurethane acrylate, modified inorganic powder, reactive diluent, photoinitiator, and additives. The synergistic effect of these raw materials results in a UV-curable coating that, after curing, forms a film with excellent pencil hardness and adhesion. The addition of modified inorganic materials to the UV-curable coating system allows the modified inorganic materials to bond with the polyurethane acrylate, enhancing the overall strength of the film. Detailed Implementation

[0016] The technical solution of the present invention will be described in detail through specific embodiments.

[0017] Unless otherwise specified, all materials and reagents used in the following examples and comparative examples are commercially available.

[0018] Example 1

[0019] A UV-curable coating comprises the following raw materials in parts by weight: 40 parts polyurethane acrylate, 10 parts modified inorganic powder, 8 parts trimethylolpropane trimethacrylate, 0.5 parts triethanolamine, 2.5 parts 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1.5 parts defoamer, and 1.5 parts leveling agent.

[0020] The method for preparing modified inorganic powder includes the following steps: urea, talc, and silica are mixed evenly in a mass ratio of 7:2:10 and calcined to obtain a mixture; 3wt% trimethoxysilane solution is added to the mixture and mixed evenly; the mixture is then dried to obtain modified inorganic powder; the calcination includes first heating to 110℃ at 2℃ / min and holding for 15min, then heating to 550℃ at 5℃ / min and holding for 4h; the mass ratio of the mixture to the trimethoxysilane solution is 1:2.

[0021] A method for preparing a UV-curable coating includes the following steps:

[0022] After ultrasonically dispersing modified silica and trimethylolpropane trimethacrylate, polyurethane acrylate, triethanolamine, 2-hydroxy-2-methyl-1-phenyl-1-propanone, defoamer, and leveling agent are added and mixed evenly to obtain a UV-curable coating.

[0023] Example 2

[0024] A UV-curable coating comprises the following raw materials in parts by weight: 35 parts polyurethane acrylate, 8 parts modified inorganic powder, 7 parts trimethylolpropane trimethacrylate, 0.5 parts triethanolamine, 2.5 parts 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1 part defoamer, and 1 part leveling agent.

[0025] The method for preparing modified inorganic powder includes the following steps: urea, talc, and silica are mixed evenly in a mass ratio of 7:2:10 and calcined to obtain a mixture; 3wt% trimethoxysilane solution is added to the mixture and mixed evenly; the mixture is then dried to obtain modified inorganic powder; the calcination includes first heating to 110℃ at 2℃ / min and holding for 15min, then heating to 550℃ at 5℃ / min and holding for 4h; the mass ratio of the mixture to the trimethoxysilane solution is 1:2.

[0026] A method for preparing a UV-curable coating includes the following steps:

[0027] After ultrasonically dispersing modified silica and trimethylolpropane trimethacrylate, polyurethane acrylate, triethanolamine, 2-hydroxy-2-methyl-1-phenyl-1-propanone, defoamer, and leveling agent are added and mixed evenly to obtain a UV-curable coating.

[0028] Example 3

[0029] A UV-curable coating comprises the following raw materials in parts by weight: 45 parts polyurethane acrylate, 12 parts modified inorganic powder, 9 parts trimethylolpropane trimethacrylate, 0.5 parts triethanolamine, 2.5 parts 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1.5 parts defoamer, and 1.5 parts leveling agent.

[0030] The method for preparing modified inorganic powder includes the following steps: urea, talc, and silica are mixed evenly in a mass ratio of 6:1:10 and calcined to obtain a mixture; 3wt% trimethoxysilane solution is added to the mixture and mixed evenly; the mixture is then dried to obtain modified inorganic powder; the calcination includes first heating to 110℃ at 2℃ / min and holding for 15min, then heating to 550℃ at 5℃ / min and holding for 4h; the mass ratio of the mixture to the trimethoxysilane solution is 1:2.

[0031] A method for preparing a UV-curable coating includes the following steps:

[0032] After ultrasonically dispersing modified silica and trimethylolpropane trimethacrylate, polyurethane acrylate, triethanolamine, 2-hydroxy-2-methyl-1-phenyl-1-propanone, defoamer, and leveling agent are added and mixed evenly to obtain a UV-curable coating.

[0033] Example 4

[0034] A UV-curable coating comprises the following raw materials in parts by weight: 42 parts polyurethane acrylate, 13 parts modified inorganic powder, 10 parts trimethylolpropane trimethacrylate, 0.5 parts triethanolamine, 2.5 parts 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1.5 parts defoamer, and 1.5 parts leveling agent.

[0035] The method for preparing modified inorganic powder includes the following steps: urea, talc, and silica are mixed evenly in a mass ratio of 7:2:11 and calcined to obtain a mixture; 3wt% trimethoxysilane solution is added to the mixture and mixed evenly; the mixture is then dried to obtain modified inorganic powder; the calcination includes first heating to 105℃ at 2℃ / min and holding for 20min, then heating to 550℃ at 5℃ / min and holding for 4h; the mass ratio of the mixture to the trimethoxysilane solution is 1:2.

[0036] A method for preparing a UV-curable coating includes the following steps:

[0037] After ultrasonically dispersing modified silica and trimethylolpropane trimethacrylate, polyurethane acrylate, triethanolamine, 2-hydroxy-2-methyl-1-phenyl-1-propanone, defoamer, and leveling agent are added and mixed evenly to obtain a UV-curable coating.

[0038] Comparative Example 1

[0039] A UV-curable coating comprises the following raw materials in parts by weight: 40 parts polyurethane acrylate, 10 parts modified inorganic powder, 8 parts trimethylolpropane trimethacrylate, 0.5 parts triethanolamine, 2.5 parts 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1.5 parts defoamer, and 1.5 parts leveling agent.

[0040] The method for preparing modified inorganic powder includes the following steps: mixing silica and 3wt% trimethoxysilane solution at a mass ratio of 1:2, and drying to obtain modified inorganic powder.

[0041] A method for preparing a UV-curable coating includes the following steps:

[0042] After ultrasonically dispersing modified silica and trimethylolpropane trimethacrylate, polyurethane acrylate, triethanolamine, 2-hydroxy-2-methyl-1-phenyl-1-propanone, defoamer, and leveling agent are added and mixed evenly to obtain a UV-curable coating.

[0043] The coating film prepared above was cured under ultraviolet light to form a thin film. Its pencil hardness was tested according to GB / T6739-2022; its adhesion was tested according to GB / T 9286-2021. The grades were as follows: Grade 0 - completely smooth cut edges, no peeling within the grid; Grade 1 - minor coating peeling at cut intersections, but the affected cross-cut area is no more than 5%; Grade 2 - coating peeling at cut intersections and / or along the cut edges, the affected cross-cut area is greater than 5% but not more than 15%; Grade 3 - coating peeling off partially or completely along the cut edges in large fragments, and / or partially or completely peeling off at different locations on the grid, the affected cross-cut area is greater than 15% but not more than 35%; Grade 4 - coating peeling off in large fragments along the cut edges, and / or some squares partially or completely peeling off, the affected cross-cut area is greater than 35% but not more than 65%; Grade 5 - peeling exceeding the level of Grade 4. The test results are shown in Table 1.

[0044] Table 1

[0045] Example 1 6H Level 0 Example 2 6H Level 0 Example 3 6H Level 0 Example 4 7H Level 0 Comparative Example 1 5H Level 0

[0046] As can be seen from the data in Table 1, the UV-curable coating prepared by this invention forms a film with excellent pencil hardness and adhesion after curing. Comparative Example 1 shows that the pencil hardness of the film prepared without adding urea and talc to the modified inorganic powder decreases. In summary, the UV-curable coating of this invention exhibits excellent performance.

[0047] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A UV-curable coating, characterized in that, The raw materials include the following parts by weight: 30-45 parts polyurethane acrylate, 5-15 parts modified inorganic powder, 5-15 parts reactive diluent, 1-5 parts photoinitiator, and 2-5 parts additives. The method for preparing the modified inorganic powder includes the following steps: mixing urea, talc, and silica evenly and calcining to obtain a mixture; adding trimethoxysilane solution to the mixture, mixing evenly, and drying to obtain the modified inorganic powder; the mass ratio of the mixture to the trimethoxysilane solution is 1:

2. The mass ratio of urea, talc, and silica is (5-10):(0.5-2):(5-10). The calcination process includes first heating to 100-200℃ at a rate of 2-3℃ / min and holding for 10-30 min, then heating to 500-600℃ at a rate of 5-10℃ / min and holding for 3-6 h; the mass fraction of the trimethoxysilane solution is 1-10 wt%.

2. The UV-curable coating according to claim 1, characterized in that, The active diluent is trimethylolpropane trimethacrylate.

3. The UV-curable coating according to claim 1, characterized in that, The photoinitiator comprises triethanolamine and 2-hydroxy-2-methyl-1-phenyl-1-propanone, wherein the mass ratio of triethanolamine to 2-hydroxy-2-methyl-1-phenyl-1-propanone is (0.1-0.5):

1.

4. A method for preparing the ultraviolet-curable coating according to any one of claims 1-3, characterized in that, Includes the following steps: After ultrasonically dispersing the modified inorganic powder and reactive diluent, polyurethane acrylate, photoinitiator, and additives are added and mixed evenly to obtain a UV-curable coating.