Novel washable light-cured 3D printing material and preparation method thereof

Abstract

The invention discloses a novel washable light-cured 3D printing material and a preparation method, and relates to the technical field of 3D printing photosensitive resin materials. The characteristics of the polyethylene glycol diacrylate and the glyceryl acrylate are utilized to construct a tough and hydrolyzable network structure, and the washing performance and the strength of the composition are improved. The low-melting-point metal material is prepared through mechanical alloying of bismuth powder, indium powder and gallium powder, the surface of the metal material is provided with sulfydryl groups, and the compatibility and dispersity of the metal material and resin are improved. The metal material serves as a reinforcement to participate in photocuring crosslinking, and the mechanical strength of the 3D printing material is remarkably enhanced. And in the heat treatment stage after cleaning, the metal material is melted and adheres to and solidifies the resin network and the ceramic particles due to the low melting point characteristic of the metal material, and the mechanical strength of the 3D printing material is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing photosensitive resin materials, and specifically to a novel water-washable light-curable 3D printing material and a preparation method thereof. Background Art

[0002] Stereolithography 3D printing technology, with its high precision, efficiency, and surface quality, holds great potential in precision manufacturing, medicine, dentistry, jewelry, and other fields. The core of this technology lies in photocurable liquid resin materials. However, while existing commercial photocurable resins strive for high performance, particularly high mechanical strength, they often face a key bottleneck: post-processing and cleaning difficulties while struggling to maintain a balance between mechanical properties.

[0003] To facilitate the removal of uncured resin residue after printing, the development of water-washable resins is crucial. The current mainstream approach is to introduce hydrophilic components, such as polyethylene glycol or its derivatives. While these materials significantly improve water washability, their high hydrophilicity often weakens the intermolecular forces within the cured network, sacrificing the material's crosslinking density and ultimate mechanical strength. Existing technologies struggle to achieve efficient and thorough water washing while also imparting the high strength and rigidity required for practical applications.

[0004] To improve the mechanical properties of photocurable resins, the addition of inorganic fillers is a common strategy. However, the dispersibility and compatibility of such reinforcements in the resin matrix are significant challenges. Micro- and nanofillers are prone to agglomeration, especially in resin systems with high viscosities, leading to stress concentration and potentially reducing strength. The interfacial bonding between inorganic fillers and the organic resin matrix is ​​generally weak, resulting in low stress transfer efficiency and an inability to fully realize the filler's reinforcing potential. Although surface modification of fillers is a common method to improve compatibility, the effect is often limited and the process is complex.

[0005] Therefore, the current field of photocurable 3D printing materials urgently needs to break through the following key limitations: develop a new material system that can effectively and synergistically resolve the contradiction between "efficient water washability" and "high mechanical strength"; at the same time, the introduced reinforcement must have excellent resin compatibility and dispersion stability, and be able to make full use of the post-processing steps of the 3D printing process to achieve a strong bond with the resin matrix, thereby significantly improving the comprehensive mechanical properties of the material without adding complex processes. Summary of the Invention

[0006] The purpose of the present invention is to provide a novel water-washable light-curable 3D printing material and a preparation method thereof, so as to solve the problems existing in the prior art.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: a new type of water-washable light-curable 3D printing material, comprising, by weight: 20-40 parts of photosensitive oligomer; 5-10 parts of hydroxyethyl methacrylate; 1-6 parts of glyceryl acrylate; 10-15 parts of polyethylene glycol diacrylate; 1-5 parts of trimethylolpropane triacrylate; 5-10 parts of low melting point alloy powder; 5-10 parts of ceramic powder; 1-3 parts of photoinitiator; 0.1-1 part of hydrophilic fumed silica; The preparation method of the low melting point alloy powder comprises the following steps: placing bismuth powder, indium powder and gallium powder into a high energy ball mill, grinding for 20-40 hours under argon protection, and then performing surface modification treatment to obtain the powder.

[0008] The present invention adopts the physical swelling of polyethylene glycol diacrylate and the polyhydroxy hydration of glycerol acrylate to synergistically construct a high-strength but water-destructible network, thereby simultaneously improving the washability and strength of the composition.

[0009] Furthermore, the average particle size of the hydrophilic fumed silica is 5-25 nm, and the specific surface area is 200-400 m 2 / g, manufacturer: Evonik Degussa, brand: AEROSIL 300.

[0010] Furthermore, the photosensitive oligomer is one or a combination of more than one of waterborne polyurethane acrylic resin, waterborne polyester acrylic resin and waterborne epoxy acrylic resin.

[0011] Furthermore, the photoinitiator is at least one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, benzoin ethyl ether, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, isopropylthioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone and 2-ethylanthraquinone.

[0012] Furthermore, the polyethylene glycol diacrylate has a molecular weight of 400 and is PEG400DA from Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.

[0013] Furthermore, the ceramic powder is one or more of SiO2, Al2O3, MgO, CaO, Sm2O3, and ZrO2.

[0014] Furthermore, the particle size of the bismuth powder, indium powder and gallium powder is 10-30 μm.

[0015] Furthermore, the mass ratio of the bismuth powder, indium powder, and gallium powder is 60:30-35:22-25.

[0016] Furthermore, the surface modification treatment is specifically as follows: mercaptopropyltrimethoxysilane (specifically KH-590 produced by Guangzhou Zhongjie New Materials Co., Ltd.), anhydrous ethanol and water are mixed, the pH is adjusted, and the hydrolysis time is controlled to 1-2 hours; the ground alloy is immersed in the hydrolyzed silane coupling agent alcohol aqueous solution for 30 minutes, and then filtered and dried.

[0017] Furthermore, the mass ratio of mercaptopropyltrimethoxysilane, anhydrous ethanol and water is 1:5-10:1.

[0018] Furthermore, the pH adjustment is specifically: adding acetic acid to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention uses bismuth powder, indium powder, and gallium powder as main raw materials and successfully prepares a metal material with low melting point characteristics through mechanical alloying. The surface is coated with mercapto groups to improve the compatibility and dispersibility in the resin. This metal material acts as a reinforcement and participates in photocuring cross-linking, significantly improving the mechanical strength of the 3D printed material. At the same time, during the heat treatment stage after the 3D printed material is cleaned, due to the relatively low melting point of the metal material, the metal material melts and infiltrates the surrounding cured resin network and ceramic particles during the heat treatment stage, which can firmly bond the entire structure together and improve the mechanical strength of the 3D printed material.

[0020] The 3D printing material composition of the present invention has good hydrophilicity. After 3D printing is completed, the 3D printed model only needs to be quickly rinsed with water to basically dissolve the excess material, and its surface can be efficiently cleaned. At the same time, by adding low-melting-point alloy powder to the composition, the mechanical strength of the 3D printing material is improved while ensuring water-washing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 This is a green part produced by a 3D printing device using the corresponding composition of Example 8; Figure 2 This is a schematic diagram of the green body of the part produced in Example 8 after preliminary cleaning with a scraper and before water cleaning; Figure 3 This is a schematic diagram of the state of the green body of the part produced in Example 8 being washed and cleaned; Figure 4This is a schematic diagram of the state in which the green body of the part produced in Example 8 is completely cleaned; In the picture: Figure 1 The inside of the frame is the green body, and the outside of the frame is the uncured resin remaining after printing. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] Example 1; (1) Bismuth powder with a particle size of 10 μm, indium powder with a particle size of 10 μm, and gallium powder with a particle size of 10 μm were loaded into a high-energy ball mill at a mass ratio of 60:30:22, and ground under argon protection for 24 hours; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:5:1, acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 1 hour; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.4, the soaking time was 30 minutes, and then filtered and dried at 60°C for 12 hours to obtain a low-melting-point alloy powder; (2) In parts by weight, 20 parts of waterborne polyurethane acrylic resin, 5 parts of hydroxyethyl methacrylate, 1 part of glycerol acrylate, 10 parts of polyethylene glycol diacrylate with a molecular weight of 400, 1 part of trimethylolpropane triacrylate, 5 parts of low melting point alloy powder, 5 parts of SiO2 with a particle size of 10 μm, 1 part of photoinitiator, and 0.1 part of hydrophilic fumed silica were added into a blender. Under room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition. Specifically, the waterborne polyurethane acrylic resin was W-2110 produced by ICL Company of the United Kingdom. The photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and benzoin ethyl ether in a mass ratio of 0.5:1.

[0024] Example 2; (1) Bismuth powder with a particle size of 12 μm, indium powder with a particle size of 10 μm, and gallium powder with a particle size of 12 μm were loaded into a high-energy ball mill at a mass ratio of 60:30:22, and ground under argon protection for 24 hours; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:5.7:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 1 hour; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.4, the soaking time was 30 minutes, and then filtered and dried at 60°C for 12 hours to obtain a low-melting-point alloy powder; (2) In parts by weight, 22 parts of waterborne polyurethane acrylic resin, 5 parts of hydroxyethyl methacrylate, 1 part of glycerol acrylate, 10.7 parts of polyethylene glycol diacrylate with a molecular weight of 400, 2 parts of trimethylolpropane triacrylate, 5.7 parts of low melting point alloy powder, 6 parts of Al2O3 with a particle size of 10 μm, 1 part of photoinitiator, and 0.2 parts of hydrophilic fumed silica were added into a blender. The mixture was stirred at room temperature at a speed of 500 r / min for 1 hour and allowed to stand for 2 hours to obtain a composition. Specifically, the waterborne polyurethane acrylic resin was W-2200 produced by ICL, a British company. The photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4,6-trimethylbenzophenone in a mass ratio of 1:1.

[0025] Example 3; (1) Bismuth powder with a particle size of 15 μm, indium powder with a particle size of 15 μm, and gallium powder with a particle size of 10 μm were loaded into a high-energy ball mill at a mass ratio of 60:31:23, and ground under argon protection for 24 hours; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:5:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 1 hour; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.5, the soaking time was 30 minutes, and then filtered and dried at 60°C for 12 hours to obtain a low-melting-point alloy powder; (2) In parts by weight, 25 parts of waterborne polyurethane acrylic resin, 6.4 parts of hydroxyethyl methacrylate, 3 parts of glycerol acrylate, 13 parts of polyethylene glycol diacrylate with a molecular weight of 400, 3 parts of trimethylolpropane triacrylate, 7 parts of low melting point alloy powder, 4 parts of MgO with a particle size of 10 μm, 1 part of photoinitiator, and 0.35 parts of hydrophilic fumed silica were added into a blender. Under room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition. Specifically, the waterborne polyurethane acrylic resin was W-2310 produced by ICL Company of the United Kingdom. The photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 4-methylbenzophenone in a mass ratio of 1:1.

[0026] Example 4; (1) Bismuth powder with a particle size of 18 μm, indium powder with a particle size of 18 μm, and gallium powder with a particle size of 30 μm were charged into a high-energy ball mill at a mass ratio of 60:32:22, and ground under argon protection for 30 hours; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:7:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 1 hour; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.6, the soaking time was 30 minutes, and then filtered and dried at 60°C for 12 hours to obtain a low-melting-point alloy powder; (2) In parts by weight, 28 parts of waterborne polyurethane acrylic resin W-2310, 7 parts of hydroxyethyl methacrylate, 4 parts of glycerol acrylate, 12 parts of polyethylene glycol diacrylate with a molecular weight of 400, 4 parts of trimethylolpropane triacrylate, 7 parts of low melting point alloy powder, 5 parts of Sm2O3 with a particle size of 10 μm, 2 parts of photoinitiator, and 0.4 parts of hydrophilic fumed silica were added into a blender. At room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4-diethylthioxanthone in a mass ratio of 2:1.

[0027] Example 5; (1) Bismuth powder with a particle size of 21 μm, indium powder with a particle size of 10 μm, and gallium powder with a particle size of 18 μm were loaded into a high-energy ball mill at a mass ratio of 60:33:24, and ground for 30 h under argon protection; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:7:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 2 h; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.7, the soaking time was 30 min, and then filtered and dried at 60°C for 12 h to obtain a low-melting-point alloy powder; (2) In parts by weight, 31 parts of waterborne polyurethane acrylic resin W-2200, 10 parts of hydroxyethyl methacrylate, 6 parts of glycerol acrylate, 15 parts of polyethylene glycol diacrylate with a molecular weight of 400, 5 parts of trimethylolpropane triacrylate, 10 parts of low melting point alloy powder, 5 parts of SiO2 with a particle size of 10 μm, 3 parts of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, and 0.6 parts of hydrophilic fumed silica were added into a blender. The mixture was stirred at room temperature at a speed of 500 r / min for 1 h and allowed to stand for 2 h to obtain a composition.

[0028] Example 6; (1) Bismuth powder with a particle size of 24 μm, indium powder with a particle size of 10 μm, and gallium powder with a particle size of 24 μm were charged into a high-energy ball mill at a mass ratio of 60:30:22, and ground for 30 h under argon protection; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:5:1, acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 2 h; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.4, the soaking time was 30 min, and then filtered and dried at 60°C for 12 h to obtain a low-melting-point alloy powder; (2) In parts by weight, 34 parts of waterborne polyurethane acrylic resin W-2110, 6 parts of hydroxyethyl methacrylate, 1 part of glycerol acrylate, 11 parts of polyethylene glycol diacrylate with a molecular weight of 400, 1 part of trimethylolpropane triacrylate, 6 parts of low melting point alloy powder, 10 parts of Al2O3 with a particle size of 10 μm, 2 parts of photoinitiator, and 0.7 parts of hydrophilic fumed silica were added into a blender. At room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and benzoin ethyl ether in a mass ratio of 0.5:1.

[0029] Example 7; (1) Bismuth powder with a particle size of 27 μm, indium powder with a particle size of 24 μm, and gallium powder with a particle size of 10 μm were loaded into a high-energy ball mill at a mass ratio of 60:33:22, and ground under argon protection for 40 hours; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:6:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 2 hours; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.5, the soaking time was 30 minutes, and then filtered and dried at 60°C for 12 hours to obtain a low-melting-point alloy powder; (2) In parts by weight, 37 parts of waterborne polyurethane acrylic resin W-2200, 8 parts of hydroxyethyl methacrylate, 4 parts of glycerol acrylate, 12 parts of polyethylene glycol diacrylate with a molecular weight of 400, 5 parts of trimethylolpropane triacrylate, 7 parts of low melting point alloy powder, 10 parts of MgO with a particle size of 10 μm, 3 parts of photoinitiator, and 0.8 parts of hydrophilic fumed silica were added into a blender. At room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4,6-trimethylbenzophenone in a mass ratio of 1:1.

[0030] Example 8; (1) Bismuth powder with a particle size of 30 μm, indium powder with a particle size of 30 μm, and gallium powder with a particle size of 30 μm were charged into a high-energy ball mill at a mass ratio of 60:35:24, and ground under argon protection for 40 hours; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:10:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 2 hours; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.8, the soaking time was 30 minutes, and then filtered and dried at 60°C for 12 hours to obtain a low-melting-point alloy powder; (2) In parts by weight, 40 parts of waterborne polyurethane acrylic resin W-2310, 10 parts of hydroxyethyl methacrylate, 6 parts of glycerol acrylate, 10 parts of polyethylene glycol diacrylate with a molecular weight of 400, 2 parts of trimethylolpropane triacrylate, 7 parts of low melting point alloy powder, 9 parts of CaO with a particle size of 10 μm, 3 parts of photoinitiator, and 1 part of hydrophilic fumed silica were added into a blender. Under room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4-diethylthioxanthone in a mass ratio of 2:1.

[0031] Comparative Example 1: (1) Bismuth powder with a particle size of 30 μm, indium powder with a particle size of 30 μm, and gallium powder with a particle size of 30 μm were placed in a high-energy ball mill at a mass ratio of 60:35:24, and ground for 40 hours under argon protection to obtain a low-melting-point alloy powder; (2) In parts by weight, 40 parts of waterborne polyurethane acrylic resin W-2310, 10 parts of hydroxyethyl methacrylate, 6 parts of glycerol acrylate, 10 parts of polyethylene glycol diacrylate with a molecular weight of 400, 2 parts of trimethylolpropane triacrylate, 7 parts of low melting point alloy powder, 9 parts of CaO with a particle size of 10 μm, 3 parts of photoinitiator, and 1 part of hydrophilic fumed silica were added into a blender. Under room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4-diethylthioxanthone in a mass ratio of 2:1.

[0032] Comparative Example 2: In parts by weight, 40 parts of waterborne polyurethane acrylic resin W-2310, 10 parts of hydroxyethyl methacrylate, 6 parts of glycerol acrylate, 10 parts of polyethylene glycol diacrylate with a molecular weight of 400, 2 parts of trimethylolpropane triacrylate, 9 parts of CaO with a particle size of 10 μm, 3 parts of photoinitiator, and 1 part of hydrophilic fumed silica were added to a blender. Under room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4-diethylthioxanthone in a mass ratio of 2:1.

[0033] Comparative Example 3; (1) Bismuth powder with a particle size of 30 μm, indium powder with a particle size of 30 μm, and gallium powder with a particle size of 30 μm were charged into a high-energy ball mill at a mass ratio of 60:35:24, and ground for 40 h under argon protection; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:10:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 2 h; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.8, the soaking time was 30 min, and then filtered and dried at 60°C for 12 h to obtain a low-melting-point alloy powder; (2) By weight, 40 parts of waterborne polyurethane acrylic resin W-2310, 10 parts of hydroxyethyl methacrylate, 6 parts of glycerol acrylate, 2 parts of trimethylolpropane triacrylate, 7 parts of low melting point alloy powder, 9 parts of CaO with a particle size of 10 μm, 3 parts of photoinitiator, and 1 part of hydrophilic fumed silica were added into a blender. Under room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4-diethylthioxanthone in a mass ratio of 2:1.

[0034] Comparative Example 4; (1) Bismuth powder with a particle size of 30 μm, indium powder with a particle size of 30 μm, and gallium powder with a particle size of 30 μm were charged into a high-energy ball mill at a mass ratio of 60:35:24, and ground for 40 h under argon protection; mercaptopropyltrimethoxysilane, anhydrous ethanol, and water were mixed at a mass ratio of 1:10:1, and acetic acid was added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4, and the hydrolysis time was controlled to 2 h; the ground alloy was immersed in a hydrolyzed silane coupling agent alcohol aqueous solution, the mass ratio of the ground alloy to mercaptopropyltrimethoxysilane was 1:0.8, the soaking time was 30 min, and then filtered and dried at 60°C for 12 h to obtain a low-melting-point alloy powder; (2) In parts by weight, 40 parts of waterborne polyurethane acrylic resin W-2310, 10 parts of hydroxyethyl methacrylate, 6 parts of glycerol acrylate, 10 parts of polyethylene glycol diacrylate with a molecular weight of 400, 7 parts of low melting point alloy powder, 9 parts of CaO with a particle size of 10 μm, 3 parts of photoinitiator, and 1 part of hydrophilic fumed silica were added into a blender. At room temperature, the speed was 500 r / min, stirred for 1 hour, and allowed to stand for 2 hours to obtain a composition; the photoinitiator was 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and 2,4-diethylthioxanthone in a mass ratio of 2:1.

[0035] Effect Examples The resin compositions prepared in Examples 1-8 and Comparative Examples 1-4 were used to print test samples using a HunterDLD light-curing printer from Zhejiang FlashCast 3D Co., Ltd. The samples were washed with tap water and dried, and then placed in a 130°C oven for 2 hours for post-treatment. The comprehensive properties of the example samples, such as water-wash cleanliness, tensile strength, elongation at break, and hardness, are compared in Table 1 below.

[0036] Tensile test: According to ISO527 standard, INSTRON5966 electronic universal material testing machine, tensile rate 50mm / min.

[0037] Sample water wash cleanliness test: visual inspection and touch, 10 points represent the best and 1 point represents the worst.

[0038] Table 1 As shown in Table 1, the cleanliness score of the present invention after water washing is ≥ 8 points (out of 10 points), indicating that the uncured resin can be efficiently removed and can be efficiently washed with water. At the same time, the tensile strength is greater than 30 MPa. Therefore, the present invention uses a combination of water-based resin and low-melting-point alloy to enable the 3D printing material to have both good water washability and mechanical strength.

[0039] The present invention utilizes the physical swelling of polyethylene glycol diacrylate and the polyhydroxy hydration of glycerol acrylate to synergistically construct a high-strength, water-destructible network, thereby simultaneously improving the washability and strength of the composition. The present invention utilizes bismuth powder, indium powder, and gallium powder as primary raw materials, and successfully prepares a metal material with low melting point properties through mechanical alloying. The metal material is coated with mercapto groups on the surface to improve compatibility and dispersibility in the resin. This metal material acts as a reinforcement, participating in photocuring and crosslinking, significantly improving the mechanical strength of the 3D printed material. Furthermore, during the heat treatment phase after washing the 3D printed material, due to its relatively low melting point, the metal material melts and infiltrates the surrounding cured resin network and ceramic particles, firmly bonding the entire structure together and improving the mechanical strength of the 3D printed material.

[0040] 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 embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed therein. Any reference in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A new type of water-washable light-curable 3D printing material, characterized by: Calculated by weight, comprising: 20-40 parts of photosensitive oligomer; 5-10 parts of hydroxyethyl methacrylate; 1-6 parts of glyceryl acrylate; 10-15 parts of polyethylene glycol diacrylate; 1-5 parts of trimethylolpropane triacrylate; 5-10 parts of low melting point alloy powder; 5-10 parts of ceramic powder; 1-3 parts of photoinitiator; 0.1-1 part of hydrophilic fumed silica; The preparation method of the low melting point alloy powder comprises the following steps: placing bismuth powder, indium powder and gallium powder into a high energy ball mill, grinding for 20-40 hours under argon protection, and then performing surface modification treatment to obtain the powder.

2. A novel water-washable light-curable 3D printing material according to claim 1, characterized in that: The photosensitive oligomer is one or a combination of more than one of waterborne polyurethane acrylic resin, waterborne polyester acrylic resin and waterborne epoxy acrylic resin.

3. The novel water-washable light-curable 3D printing material according to claim 1, characterized in that: The photoinitiator is at least one of benzoin ethyl ether, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, isopropylthioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone and 2-ethylanthraquinone.

4. The novel water-washable light-curable 3D printing material according to claim 1, characterized in that: The molecular weight of the polyethylene glycol diacrylate is 400.

5. The novel water-washable light-curable 3D printing material according to claim 1, characterized in that: The ceramic powder is one or more of SiO2, Al2O3, MgO, CaO, Sm2O3, and ZrO2.

6. The novel water-washable light-curable 3D printing material according to claim 1, characterized in that: The particle size of the bismuth powder, indium powder and gallium powder is 10-30 μm.

7. The novel water-washable light-curable 3D printing material according to claim 1, characterized in that: The mass ratio of the bismuth powder, indium powder and gallium powder is 60:30-35:22-25.

8. The novel water-washable light-curable 3D printing material according to claim 1, characterized in that: The surface modification treatment is specifically as follows: mixing mercaptopropyltrimethoxysilane, anhydrous ethanol and water, adjusting the pH, and controlling the hydrolysis time to 1-2 hours; soaking the ground alloy in a hydrolyzed silane coupling agent alcohol aqueous solution for 30 minutes, and then filtering and drying.

9. The novel water-washable light-curable 3D printing material according to claim 8, characterized in that: The mass ratio of the mercaptopropyltrimethoxysilane, anhydrous ethanol and water is 1:5-10:

1.

10. The novel water-washable light-curable 3D printing material according to claim 8, characterized in that: The pH adjustment is specifically as follows: acetic acid is added to adjust the pH value of the mercaptopropyltrimethoxysilanol aqueous solution to 4.

Images