Glass composite heating bed for 3D printer and preparation method thereof

Abstract

A glass composite heating bed for a 3D printer and a preparation method thereof, which adopts a glass substrate, coats multifunctional heat-conducting glue on the front and back surfaces of the glass substrate; the multifunctional heat-conducting glue comprises a heat-conducting glue main body and a solvent; when prepared, various types of epoxy resins, toughening agents, diluents and the solvent are added into a container, sealed and stirred until mixed uniformly to obtain a first mixture; then inorganic particles, chopped fibers, the solvent and auxiliaries are mixed and stirred uniformly to obtain a mixed powder dispersion liquid; the mixed powder dispersion liquid and the first mixture are mixed uniformly to obtain a second mixture liquid, finally a curing agent is added and continuously stirred uniformly to obtain the heat-conducting glue main body; after the high-heat-conducting glue is coated on the surface of the glass substrate, the heat conductivity of the glass substrate can be effectively increased, the heat propagation is faster, the overall heat resistance is not lower than 300 DEG C, and the glass substrate can be effectively prevented from being fragile under the conditions of uneven stress or impact.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary fields of materials science and mechanical manufacturing, and specifically relates to a glass composite material heated bed for 3D printers and its preparation method. Background Technology

[0002] With the rapid development and functional improvements of 3D printers, higher demands are being placed on the heated beds used in 3D printers. The focus is shifting from single-function and low-precision to high-precision and multi-functionality. Specifically, the heated bed needs to heat up quickly and reach higher temperatures (from the original 60℃ to over 120℃), with small temperature differences between different areas, a planar deformation of the printing platform not exceeding 0.2mm, and low manufacturing costs. The heated bed is a key component of a 3D printer, and meeting all these requirements simultaneously presents a significant challenge in its manufacturing.

[0003] 3D printer heated beds can currently be categorized into five main types based on their material and structure: 1) Aluminum heated beds: This is the most common type, usually used in combination with PCB heating films. Its advantages include fast heat conduction and uniform temperature rise. The disadvantages are that the aluminum thickness must be at least 5mm, otherwise it will affect the flatness deformation, making processing difficult and resulting in higher manufacturing costs. 2) Glass heated beds: These are often used with aluminum substrate heating plates. Their advantages include high surface flatness, good electrical insulation, and high temperature resistance, as well as low manufacturing costs. The disadvantages are that they are fragile, inconvenient to install, and glass has a high heat capacity but slow heating, making it difficult to integrate with metal structural components, i.e., difficult to fix. Drilling holes in the glass will affect its strength. 3) Copper tube heated bed: Heating wires are inserted into copper tubes, which are then filled with diamond powder and brazed onto die-cast aluminum. Finally, the tubes are attached to the back of the heated bed. Stainless steel tubes are also used. This structure is a traditional heating method (similar to kettles used for boiling water). Its advantages are rapid heating, but its disadvantages include low insulation strength, high failure rate, short lifespan, and significant deformation of the heating platform. 4) Silicone heated bed (silicone heating pad): Thin and flexible, it can be attached to the back of aluminum or steel plates for DIY or industrial applications. Its advantages are high temperature resistance and high insulation, but its disadvantages include poor thermal conductivity, slow heating, and higher cost when attached to the aluminum platform. 5) Epoxy resin glass cloth heated bed, similar to silicone heating film: Epoxy resin glass cloth laminate is bonded to the back of the heated bed platform. The advantage is high insulation, but the disadvantages are insufficient high temperature resistance, poor heat conduction and slow temperature rise. Furthermore, because the glass fiber cloth has differences in warp and weft, there is stress after stacking and laminating, which seriously affects the flatness accuracy of the heated bed after heating.

[0004] In summary, there is an urgent need for a heated bed for 3D printers that is low in manufacturing cost, has fast heat conduction, high heat resistance, high surface flatness, is easy to fix and not easily broken. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a glass composite material heating bed for 3D printers and its preparation method. By utilizing the characteristics of glass having a large heat capacity and slow thermal conductivity, the thermal conductivity can be effectively increased after coating its surface with a multifunctional thermally conductive adhesive, allowing heat to spread faster. The overall heat resistance is not less than 300℃, which can effectively prevent the glass substrate from becoming fragile under uneven stress or impact.

[0006] To achieve the above objectives, the present invention can be implemented through the following solutions: A glass composite heated bed for 3D printers uses a glass substrate, with a multifunctional thermally conductive adhesive coated on both sides of the glass substrate. The multifunctional thermally conductive adhesive comprises a thermally conductive adhesive matrix and component D, i.e., a solvent, with a mass ratio of the thermally conductive adhesive matrix to component D of 1:0.5-0.7. The thermally conductive adhesive body comprises component A (resin), component B (inorganic particles), and component C (additives), with a mass ratio of component A: component B: component C of (30-36): (58-65): (1-2). Component A, by mass percentage, comprises: 22-35% glycidyl ether type phenolic epoxy resin F-51, 10-18% glycidyl ether type phenolic epoxy resin E-20, 5-12% glycidyl ester type phenolic epoxy resin TDE-85, 5-12% toughening agent nitrile rubber and PVB polyvinyl butyral mixture, 5-10% diluent glycidyl methacrylate, 20-25% curing agent diaminodiphenylmethane (DDM), and 0.5-1% accelerator 2(2,4,6-tris(dimethylaminomethyl)phenol; wherein the nitrile rubber in the toughening agent has a nitrile value of 40, i.e., nitrile-40, the acetal value of PVB ranges from 10-17%, and the mixing ratio of nitrile-40 to PVB is 100:(40-60).

[0007] Component B, by mass percentage, comprises: 13-20% boron nitride particles, 58-65% alumina particles, 5-12% magnesium oxide particles, and 5-10% chopped glass fibers; the boron nitride nanosheets have a thickness of 100-150 nm and a length of 10-15 μm; the chopped glass fibers have a length of 3-8 mm and a diameter of 100-120 μm; the alumina particles are spherical with a diameter range of 5-20 μm; and the magnesium oxide particles are irregularly shaped flakes with an approximate diameter of 5-10 μm and a thickness of 2-5 μm.

[0008] The C component, by mass percentage, comprises: 26-35% wetting and dispersing agent, 23-32% leveling agent, and 33-42% coupling agent; the wetting and dispersing agent includes BYK-20, BYK-40, or BYK-50, the leveling agent includes BYK-80, BYK-120, BYK-100, or BYK-550, and the coupling agent includes KH-550 or KH-560.

[0009] The D component, by mass percentage, comprises: 30-42% dimethylformamide, 25-35% ethyl acetate, and 25-35% cyclohexanone.

[0010] The method for preparing the thermally conductive adhesive substrate includes the following steps: 1) Weigh out glycidyl ether type phenolic epoxy resin F-51, glycidyl ether type phenolic epoxy resin E-20, and glycidyl ester type phenolic epoxy resin TDE-85 according to the proportions and add them to a container. Add 20-30% of the total amount of solvent in component D, seal and stir for 1-3 hours until homogeneous. Then add glycidyl methacrylate diluent to the mixed epoxy and stir continuously at room temperature for 1-2 hours. Weigh out the toughening agent mixture of nitrile rubber and PVB polyvinyl butyral, add 20-30% of the total amount of solvent in component D, and stir slowly for 5-6 hours until completely dissolved. Then add the dissolved toughening agent to the mixed epoxy and stir at 400-500 rpm for 2-3 hours until completely mixed. Finally, add accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol) and stir at 300-400 rpm for 1-2 hours to obtain a homogeneous first mixture for later use. 2) Weigh out the inorganic particles and chopped fibers of component B according to the proportion, add the remaining solvent of component D, stir at low speed for 3-4 hours, then add the auxiliary agent of component C, and stir at 100-200 rpm for 8-10 hours to obtain a mixed powder dispersion. 3) Add the mixed powder dispersion obtained in step 2) to the first mixture obtained in step 1), and stir at 200-300 rpm for 12-15 hours to obtain the second mixture; dissolve the curing agent diaminodiphenylmethane (DDM) in dimethylformamide, stir slowly for 4-5 hours until completely dissolved, and then add it to the second mixture above, and stir at 200-300 rpm for 2-3 hours at room temperature.

[0011] The method for preparing a glass composite material heated bed for 3D printers includes: casting a mixed multifunctional thermally conductive adhesive onto a glass substrate, and then baking it in a tunnel oven at different temperature ranges; bonding an alloy thin film with a specified resistance value etched onto one side of the adhesive-coated glass substrate, and pressing it in a vacuum laminator at a temperature of 220°C for 3 hours; then coating one side of the alloy foil circuit with a silicone insulating layer to obtain the glass composite material heated bed for 3D printers.

[0012] The method for preparing a glass composite heated bed for 3D printers includes the following steps: The mixed multifunctional thermally conductive adhesive is uniformly cast onto the glass substrate using a casting machine at a speed of 1-2 m / min, maintaining a coating thickness of 0.3-0.5 mm. After casting, the substrate is baked in a tunnel oven with five temperature zones: 1) room temperature - 50 degrees Celsius; 2) 50-90 degrees Celsius; 3) 90-120 degrees Celsius; 4) 120-150 degrees Celsius; 5) 150-90 degrees Celsius, with a baking speed of 2-4 m / min. An alloy foil with a specified resistance value is etched onto the adhesive-coated surface of a glass substrate and then placed in a vacuum laminator for pressing. The hot pressing temperatures are set to 90℃ for 30-50 minutes, 150℃ for 2-3 hours, 175℃ for 2-3 hours, and 200℃ for 1-2 hours. After hot pressing, the substrate is cooled to room temperature, and the adhesive-coated glass substrate is removed. Then, a layer of 107 silicone insulating layer with a thickness of 1-2 mm is coated on the alloy foil circuitry and cured at 160℃ for 5-15 minutes. Finally, a glass composite heated bed for 3D printers is obtained.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: The glass composite heated bed for 3D printers prepared by this invention has the advantage of low cost compared to the high thickness, difficult processing, and high manufacturing cost of traditional aluminum heated beds; compared to the fragility, inconvenient installation, and slow heating of traditional glass heated beds, the glass composite heated bed has the advantages of rapid heating, impact resistance, and convenient installation; compared to the low insulation strength and high failure rate of copper tube heating, it has high insulation strength and safety reliability; compared to the non-thermal conductivity of silicone heated beds, this technology has high thermal conductivity; compared to traditional epoxy resin glass cloth laminate heated beds, it effectively solves the disadvantages of insufficient temperature resistance and non-thermal conductivity, and improves the flatness accuracy of the heated bed.

[0014] The glass composite heated bed for 3D printers prepared by this invention has a thermal conductivity of up to 1.6 W / mK, which is nearly 8-9 times higher than the 0.15-0.2 W / mK thermal conductivity of non-thermally conductive polymers. Simultaneously, the insulation resistance and high electrical breakdown of the insulating silicone-assisted material provide the heated bed with excellent electrical insulation safety at high temperatures. The glass composite heated bed for 3D printers prepared by this invention can be used in various types of 3D printers. Detailed Implementation

[0015] The present invention will be described in detail below through embodiments.

[0016] Example 1: A glass composite material heating bed for 3D printers, using a glass substrate, with multifunctional thermally conductive adhesive coated on both sides of the glass substrate; The multifunctional thermally conductive adhesive comprises a thermally conductive adhesive body and a D component, i.e., a solvent, with a mass ratio of the thermally conductive adhesive body to the D component of 1:0.6. The thermally conductive adhesive body comprises component A (resin), component B (inorganic particles), and component C (additives), with a mass ratio of component A: component B: component C of 35:62:2. Component A, by mass percentage, comprises: 30% glycidyl ether type phenolic epoxy resin F-51, 15% glycidyl ether type phenolic epoxy resin E-20, 10% glycidyl ester type phenolic epoxy resin TDE-85, 10% toughening agent nitrile rubber and PVB polyvinyl butyral mixture, 9% diluent glycidyl methacrylate, 25% curing agent diaminodiphenylmethane (DDM), and 1% accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol; the nitrile rubber in the toughening agent has a nitrile value of 40, i.e., nitrile-40, the acetal value of PVB ranges from 10-17%, and the mixing ratio of nitrile-40 to PVB is 100:60.

[0017] Component B, by mass percentage, comprises: 15% boron nitride particles, 65% alumina particles, 10% magnesium oxide particles, and 10% chopped glass fibers; the boron nitride nanosheets have a thickness of 100–150 nm and a length of 10–15 μm; the chopped glass fibers have a length of 3–8 mm and a diameter of 100–120 μm; the alumina particles are spherical with a diameter ranging from 5–20 μm; and the magnesium oxide particles are irregularly shaped flakes with an approximate diameter of 5–10 μm and a thickness of 2–5 μm.

[0018] The C component, by mass percentage, comprises: 30% wetting and dispersing agent, 30% leveling agent, and 40% coupling agent; the wetting and dispersing agent is BYK-20, the leveling agent is BYK-80, and the coupling agent is KH-550.

[0019] The D component, by mass percentage, comprises: 40% dimethylformamide, 30% ethyl acetate, and 30% cyclohexanone.

[0020] The method for preparing the thermally conductive adhesive substrate includes the following steps: 1) Weigh out glycidyl ether type phenolic epoxy resin F-51, glycidyl ether type phenolic epoxy resin E-20, and glycidyl ester type phenolic epoxy resin TDE-85 according to the proportions and add them to a container. Add 25% of the total amount of solvent in component D, seal and stir for 2 hours until homogeneous. Then add glycidyl methacrylate as a diluent to the mixed epoxy and stir continuously at room temperature for 1 hour. Weigh out the toughening agent mixture of nitrile rubber and PVB polyvinyl butyral, add 25% of the total amount of solvent in component D, and stir slowly for 5 hours until completely dissolved. Then add the dissolved toughening agent to the mixed epoxy and stir at 400 rpm for 2 hours until completely mixed. Finally, add accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol) and stir at 300 rpm for 2 hours to obtain a homogeneous first mixture for later use. 2) Weigh out the inorganic particles and chopped fibers of component B according to the proportion, add the remaining solvent of component D, stir at low speed for 3 hours, then add the auxiliary agent of component C, and stir at 200 rpm for 8 hours to obtain a mixed powder dispersion. 3) Add the mixed powder dispersion obtained in step 2) to the first mixture obtained in step 1), and stir at 200 rpm for 12 hours to obtain the second mixture; dissolve the curing agent diaminodiphenylmethane (DDM) in dimethylformamide, stir slowly for 4 hours until completely dissolved, and then add it to the second mixture above, and stir at 200 rpm for 2 hours at room temperature.

[0021] The method for preparing a glass composite material heated bed for 3D printers includes: casting a mixed multifunctional thermally conductive adhesive onto a glass substrate, followed by baking in a tunnel oven at different temperature ranges; bonding an alloy thin film etched with a specified resistance value onto one side of the adhesive-coated glass substrate, and pressing it in a vacuum laminator at 220°C for 3 hours; then coating one side of the alloy foil circuit with a silicone insulating layer to obtain the glass composite material heated bed for 3D printers; including the following steps: The mixed multifunctional thermally conductive adhesive is uniformly cast onto the glass substrate using a casting machine at a speed of 1 m / min, maintaining a coating thickness of 0.3 mm. After casting, the substrate is baked in a tunnel oven with five temperature zones: 1) room temperature - 50 degrees Celsius; 2) 50-90 degrees Celsius; 3) 90-120 degrees Celsius; 4) 120-150 degrees Celsius; 5) 150-90 degrees Celsius, at a baking speed of 3 m / min. An alloy foil with a specified resistance value is etched onto the adhesive-coated surface of a glass substrate and then placed in a vacuum laminator for pressing. The hot pressing temperatures are set to 90°C for 50 minutes, 150°C for 3 hours, 175°C for 2 hours, and 200°C for 1 hour. After hot pressing, the substrate is cooled to room temperature, and the adhesive-coated glass substrate is removed. Then, a 1mm thick 107 silicone insulating layer is coated on the alloy foil circuitry and cured at 160°C for 5 minutes to obtain a glass composite heated bed for 3D printers.

[0022] Example 2: A glass composite material heating bed for 3D printers, using a glass substrate, with multifunctional thermally conductive adhesive coated on both sides of the glass substrate; The multifunctional thermally conductive adhesive comprises a thermally conductive adhesive body and a D component, i.e., a solvent, with a mass ratio of the thermally conductive adhesive body to the D component of 1:0.5. The thermally conductive adhesive body comprises component A (resin), component B (inorganic particles), and component C (additives), with a mass ratio of component A: component B: component C of 30:58:1. Component A, by mass percentage, comprises: 32% glycidyl ether type phenolic epoxy resin F-51, 14% glycidyl ether type phenolic epoxy resin E-20, 8% glycidyl ester type phenolic epoxy resin TDE-85, 11% toughening agent nitrile rubber and PVB polyvinyl butyral mixture, 9% diluent glycidyl methacrylate, 25% curing agent diaminodiphenylmethane (DDM), and 1% accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol; the nitrile rubber in the toughening agent has a nitrile value of 40, i.e., nitrile-40, the acetal value of PVB ranges from 10-17%, and the mixing ratio of nitrile-40 to PVB is 100:50.

[0023] Component B, by mass percentage, comprises: 13% boron nitride particles, 65% alumina particles, 12% magnesium oxide particles, and 10% chopped glass fibers; the boron nitride nanosheets have a thickness of 100–150 nm and a length of 10–15 μm; the chopped glass fibers have a length of 3–8 mm and a diameter of 100–120 μm; the alumina particles are spherical with a diameter range of 5–20 μm; and the magnesium oxide particles are irregularly shaped flakes with an approximate diameter of 5–10 μm and a thickness of 2–5 μm.

[0024] The C component, by mass percentage, comprises: 26% wetting and dispersing agent, 32% leveling agent, and 42% coupling agent; the wetting and dispersing agent is BYK-40, the leveling agent is BYK-120, and the coupling agent is KH-560.

[0025] The D component, by mass percentage, comprises: 42% dimethylformamide, 25% ethyl acetate, and 35% cyclohexanone.

[0026] The method for preparing the thermally conductive adhesive substrate includes the following steps: 1) Weigh out glycidyl ether type phenolic epoxy resin F-51, glycidyl ether type phenolic epoxy resin E-20, and glycidyl ester type phenolic epoxy resin TDE-85 according to the proportions and add them to a container. Add 20% of the total amount of solvent in component D, seal and stir for 2 hours until homogeneous. Then add glycidyl methacrylate diluent to the mixed epoxy and stir continuously at room temperature for 1.5 hours. Weigh out the toughening agent nitrile rubber and PVB polyvinyl butyral mixture, add 30% of the total amount of solvent in component D, and stir slowly for 5 hours until completely dissolved. Then add the dissolved toughening agent to the mixed epoxy and stir at 450 rpm for 2.5 hours until completely mixed. Finally, add accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol) and stir at 300 rpm for 1 hour to obtain a homogeneous first mixture, which is ready for use. 2) Weigh out the inorganic particles and chopped fibers of component B according to the proportion, add the remaining solvent of component D, stir at low speed for 4 hours, then add the auxiliary agent of component C, and stir at 100 rpm for 9 hours to obtain a mixed powder dispersion. 3) Add the mixed powder dispersion obtained in step 2) to the first mixture obtained in step 1), and stir at 250 rpm for 13 hours to obtain the second mixture; dissolve the curing agent diaminodiphenylmethane (DDM) in dimethylformamide, stir slowly for 5 hours until completely dissolved, and then add it to the second mixture above, and stir at 250 rpm for 2 hours at room temperature.

[0027] The method for preparing a glass composite material heated bed for 3D printers includes: casting a mixed multifunctional thermally conductive adhesive onto a glass substrate, followed by baking in a tunnel oven at different temperature ranges; bonding an alloy thin film etched with a specified resistance value onto one side of the adhesive-coated glass substrate, and pressing it in a vacuum laminator at 220°C for 3 hours; then coating one side of the alloy foil circuit with a silicone insulating layer to obtain the glass composite material heated bed for 3D printers; including the following steps: The mixed multifunctional thermally conductive adhesive is uniformly cast onto the glass substrate using a casting machine at a speed of 2 m / min, maintaining a coating thickness of 0.3 mm. After casting, the substrate is baked in a tunnel oven with five temperature zones: 1) room temperature - 50 degrees Celsius; 2) 50-90 degrees Celsius; 3) 90-120 degrees Celsius; 4) 120-150 degrees Celsius; 5) 150-90 degrees Celsius, with a baking speed of 2 m / min. An alloy foil with a specified resistance value is etched onto the adhesive-coated surface of a glass substrate and then placed in a vacuum laminator for pressing. The hot pressing temperatures are set to 90°C for 30 minutes, 150°C for 3 hours, 175°C for 2 hours, and 200°C for 1 hour. After hot pressing, the substrate is cooled to room temperature, and the adhesive-coated glass substrate is removed. Then, a 2mm thick 107 silicone insulating layer is coated on the alloy foil circuitry and cured at 160°C for 5 minutes to obtain a glass composite heated bed for 3D printers.

[0028] Example 3: A glass composite material heating bed for 3D printers, using a glass substrate, with multifunctional thermally conductive adhesive coated on both sides of the glass substrate; The multifunctional thermally conductive adhesive comprises a thermally conductive adhesive matrix and component D, i.e., a solvent, with a mass ratio of the thermally conductive adhesive matrix to component D of 1:0.5-0.7. The thermally conductive adhesive body comprises component A (resin), component B (inorganic particles), and component C (additives), with a mass ratio of component A: component B: component C of 36:65:2. Component A, by mass percentage, comprises: 35% glycidyl ether type phenolic epoxy resin F-51, 13.5% glycidyl ether type phenolic epoxy resin E-20, 5% glycidyl ester type phenolic epoxy resin TDE-85, 10% toughening agent nitrile rubber and PVB polyvinyl butyral mixture, 10% diluent glycidyl methacrylate, 25% curing agent diaminodiphenylmethane (DDM), and 0.5% accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol; the nitrile rubber in the toughening agent has a nitrile value of 40, i.e., nitrile-40, the acetal value of PVB ranges from 10-17%, and the mixing ratio of nitrile-40 to PVB is 100:40.

[0029] Component B, by mass percentage, comprises: 20% boron nitride particles, 58% alumina particles, 12% magnesium oxide particles, and 10% chopped glass fibers; the boron nitride nanosheets have a thickness of 100–150 nm and a length of 10–15 μm; the chopped glass fibers have a length of 3–8 mm and a diameter of 100–120 μm; the alumina particles are spherical with a diameter range of 5–20 μm; and the magnesium oxide particles are irregularly shaped flakes with an approximate diameter of 5–10 μm and a thickness of 2–5 μm.

[0030] The C component, by mass percentage, comprises: 26% wetting and dispersing agent, 32% leveling agent, and 42% coupling agent; the wetting and dispersing agent is BYK-50, the leveling agent is BYK-100, and the coupling agent is KH-550.

[0031] The D component, by mass percentage, comprises: 30% dimethylformamide, 35% ethyl acetate, and 35% cyclohexanone.

[0032] The method for preparing the thermally conductive adhesive substrate includes the following steps: 1) Weigh out glycidyl ether type phenolic epoxy resin F-51, glycidyl ether type phenolic epoxy resin E-20, and glycidyl ester type phenolic epoxy resin TDE-85 according to the proportions and add them to a container. Add 30% of the total amount of solvent in component D, seal and stir for 3 hours until homogeneous. Then add glycidyl methacrylate diluent to the mixed epoxy and stir continuously at room temperature for 2 hours. Weigh out the toughening agent nitrile rubber and PVB polyvinyl butyral mixture, add 20% of the total amount of solvent in component D, and stir slowly for 6 hours until completely dissolved. Then add the dissolved toughening agent to the mixed epoxy and stir at 500 rpm for 3 hours until completely mixed. Finally, add accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol) and stir at 400 rpm for 2 hours to obtain a homogeneous first mixture for later use. 2) Weigh out the inorganic particles and chopped fibers of component B according to the proportion, add the remaining solvent of component D, stir at low speed for 4 hours, then add the auxiliary agent of component C, and stir at 200 rpm for 10 hours to obtain a mixed powder dispersion. 3) Add the mixed powder dispersion obtained in step 2) to the first mixture obtained in step 1), and stir at 300 rpm for 15 hours to obtain the second mixture; dissolve the curing agent diaminodiphenylmethane (DDM) in dimethylformamide, stir slowly for 5 hours until completely dissolved, and then add it to the second mixture above, and stir at 300 rpm for 3 hours at room temperature.

[0033] The method for preparing a glass composite material heated bed for 3D printers includes: casting a mixed multifunctional thermally conductive adhesive onto a glass substrate, followed by baking in a tunnel oven at different temperature ranges; bonding an alloy thin film etched with a specified resistance value onto one side of the adhesive-coated glass substrate, and pressing it in a vacuum laminator at 220°C for 3 hours; then coating one side of the alloy foil circuit with a silicone insulating layer to obtain the glass composite material heated bed for 3D printers; including the following steps: The mixed multifunctional thermally conductive adhesive is uniformly cast onto the glass substrate using a casting machine at a speed of 2 m / min, maintaining a coating thickness of 0.5 mm. After casting, the substrate is baked in a tunnel oven with five temperature zones: 1) room temperature - 50 degrees Celsius; 2) 50-90 degrees Celsius; 3) 90-120 degrees Celsius; 4) 120-150 degrees Celsius; 5) 150-90 degrees Celsius, with a baking speed of 2 m / min. An alloy foil with a specified resistance value is etched onto the adhesive-coated surface of a glass substrate and then placed in a vacuum laminator for pressing. The hot pressing temperatures are set to 90°C for 30 minutes, 150°C for 2 hours, 175°C for 2 hours, and 200°C for 1 hour. After hot pressing, the substrate is cooled to room temperature, and the adhesive-coated glass substrate is removed. Then, a 1mm thick 107 silicone insulating layer is coated on the alloy foil circuitry and cured at 160°C for 5 minutes to obtain a glass composite heated bed for 3D printers.

[0034] Example 4: A glass composite material heated bed for 3D printers, using a glass substrate, with multifunctional thermally conductive adhesive coated on both sides of the glass substrate; The multifunctional thermally conductive adhesive comprises a thermally conductive adhesive body and a D component, i.e., a solvent, with a mass ratio of the thermally conductive adhesive body to the D component of 1:0.7. The thermally conductive adhesive body comprises component A (resin), component B (inorganic particles), and component C (additives), with a mass ratio of component A: component B: component C of 34:65:1. Component A, by mass percentage, comprises: 27.2% glycidyl ether type phenolic epoxy resin F-51, 18% glycidyl ether type phenolic epoxy resin E-20, 12% glycidyl ester type phenolic epoxy resin TDE-85, 12% toughening agent nitrile rubber and PVB polyvinyl butyral mixture, 5% diluent glycidyl methacrylate, 25% curing agent diaminodiphenylmethane (DDM), and 0.8% accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol; the nitrile rubber in the toughening agent has a nitrile value of 40, i.e., nitrile-40, the acetal value of PVB ranges from 10-17%, and the mixing ratio of nitrile-40 to PVB is 100:55.

[0035] Component B, by mass percentage, comprises: 13% boron nitride particles, 65% alumina particles, 12% magnesium oxide particles, and 10% chopped glass fibers; the boron nitride nanosheets have a thickness of 100–150 nm and a length of 10–15 μm; the chopped glass fibers have a length of 3–8 mm and a diameter of 100–120 μm; the alumina particles are spherical with a diameter range of 5–20 μm; and the magnesium oxide particles are irregularly shaped flakes with an approximate diameter of 5–10 μm and a thickness of 2–5 μm.

[0036] The C component, by mass percentage, comprises: 35% wetting and dispersing agent, 23% leveling agent, and 42% coupling agent; the wetting and dispersing agent is BYK-20, the leveling agent is BYK-550, and the coupling agent is KH-560.

[0037] The D component, by mass percentage, comprises: 42% dimethylformamide, 25% ethyl acetate, and 35% cyclohexanone.

[0038] The method for preparing the thermally conductive adhesive substrate includes the following steps: 1) Weigh out glycidyl ether type phenolic epoxy resin F-51, glycidyl ether type phenolic epoxy resin E-20, and glycidyl ester type phenolic epoxy resin TDE-85 according to the proportions and add them to a container. Add 30% of the total amount of solvent in component D, seal and stir for 1 hour until homogeneous. Then add glycidyl methacrylate as a diluent to the mixed epoxy and stir continuously at room temperature for 1 hour. Weigh out the toughening agent mixture of nitrile rubber and PVB polyvinyl butyral, add 30% of the total amount of solvent in component D, and stir slowly for 5 hours until completely dissolved. Then add the dissolved toughening agent to the mixed epoxy and stir at 400 rpm for 3 hours until completely mixed. Finally, add accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol) and stir at 400 rpm for 1 hour to obtain a homogeneous first mixture for later use. 2) Weigh out the inorganic particles and chopped fibers of component B according to the proportion, add the remaining solvent of component D, stir at low speed for 3-4 hours, then add the auxiliary agent of component C, and stir at 100 for 10 hours to obtain a mixed powder dispersion. 3) Add the mixed powder dispersion obtained in step 2) to the first mixture obtained in step 1), and stir at 200 rpm for 15 hours to obtain the second mixture; dissolve the curing agent diaminodiphenylmethane (DDM) in dimethylformamide, stir slowly for 4 hours until completely dissolved, and then add it to the second mixture above, and stir at 200 rpm for 3 hours at room temperature.

[0039] The method for preparing a glass composite material heated bed for 3D printers includes: casting a mixed multifunctional thermally conductive adhesive onto a glass substrate, followed by baking in a tunnel oven at different temperature ranges; bonding an alloy thin film etched with a specified resistance value onto one side of the adhesive-coated glass substrate, and pressing it in a vacuum laminator at 220°C for 3 hours; then coating one side of the alloy foil circuit with a silicone insulating layer to obtain the glass composite material heated bed for 3D printers; including the following steps: The mixed multifunctional thermally conductive adhesive is uniformly cast onto a glass substrate using a casting machine at a speed of 2 m / min, maintaining a coating thickness of 0.3 mm. After casting, the substrate is baked in a tunnel oven with five temperature zones: 1) room temperature - 50 degrees Celsius; 2) 50-90 degrees Celsius; 3) 90-120 degrees Celsius; 4) 120-150 degrees Celsius; 5) 150-90 degrees Celsius, with a baking speed of 2-4 m / min. An alloy foil with a specified resistance value is etched onto the adhesive-coated surface of a glass substrate and then placed in a vacuum laminator for pressing. The hot pressing temperatures are set to 90°C for 30 minutes, 150°C for 2 hours, 175°C for 3 hours, and 200°C for 2 hours. After hot pressing, the substrate is cooled to room temperature, and the adhesive-coated glass substrate is removed. Then, a 2mm thick 107 silicone insulating layer is coated on the alloy foil circuitry and cured at 160°C for 15 minutes to obtain a glass composite heated bed for 3D printers.

[0040] A comparison of the performance of the 3D printer heated beds of Examples 1-4 with dimensions of 260X260mm, including aluminum heated beds, pure glass heated beds, copper tube heated beds, silicone heated beds, and epoxy resin heated beds (AC: 220V power supply), is detailed in Table 1.

[0041] Table 1 Aluminum heated bed 1.2 Less than ≥3KV ≤200 high 45 yuan / each Pure glass heated bed 0.3 Less than ≥5KV ≤100 Difference 35 yuan / each Copper tube heated bed 5.0 Greater than ≥2KV ≤500 generally 45 yuan / each Silicone heated bed 0.1 Less than ≥5KV ≤100 high 50 yuan / each Epoxy Resin Hot Bed 0.2 Greater than ≥3KV ≤200 high 48 yuan / each Example 1 1.58 Less than ≥5KV ≤100 high 40 yuan / each Example 2 1.57 Less than ≥5KV ≤100 high 39 yuan / each Example 3 1.61 Less than ≥5KV ≤100 high 41 yuan / each Example 4 1.58 Less than ≥5KV ≤100 high 40 yuan / each Examples 1-4 exhibit a high thermal conductivity of 1.57 W / mK, exceeding that of aluminum heated beds (1.2 W / mK); a flatness ≤0.2 mm, meeting the flatness requirements of aluminum and pure glass heated beds; an insulation strength ≥5 KV / mm, meeting the insulation strength requirements of pure glass and silicone heated beds; a high-temperature leakage current ≤100 uA, meeting the high-temperature leakage current requirements of pure glass and silicone heated beds; and high reliability. The manufacturing cost is 40 yuan / unit for Example 1, 39 yuan / unit for Example 2, 41 yuan / unit for Example 3, and 40 yuan / unit for Example 4, indicating relatively low manufacturing costs. It can be seen that the glass composite material heated bed for 3D printers prepared by this invention has the advantage of low cost compared with the traditional aluminum heated bed, which has the disadvantages of high thickness, difficult processing and high manufacturing cost; compared with the traditional glass heated bed, which is fragile, inconvenient to install and slow to heat up, the glass composite material heated bed has the advantages of fast heating, impact resistance and convenient installation; compared with the low insulation strength and high failure rate of copper tube heating, it has high insulation strength and safety and reliability; compared with the non-thermal conductivity of silicone heated bed, this technology has high thermal conductivity; compared with the traditional epoxy resin glass cloth laminate heated bed, it effectively solves the disadvantages of insufficient temperature resistance and non-thermal conductivity, and improves the flatness accuracy of the heated bed.

Claims

1. A glass composite heated bed for a 3D printer, comprising a glass substrate coated with a multifunctional thermally conductive adhesive on both sides of the glass substrate; characterized in that: The multifunctional thermally conductive adhesive comprises a thermally conductive adhesive matrix and component D, i.e., a solvent, with a mass ratio of the thermally conductive adhesive matrix to component D of 1:0.5-0.

7. The thermally conductive adhesive body comprises component A (resin), component B (inorganic particles), and component C (additives), with a mass ratio of component A: component B: component C of (30-36): (58-65): (1-2). Component A, by mass percentage, comprises: 22-35% glycidyl ether type phenolic epoxy resin F-51, 10-18% glycidyl ether type phenolic epoxy resin E-20, 5-12% glycidyl ester type phenolic epoxy resin TDE-85, 5-12% toughening agent nitrile rubber and PVB polyvinyl butyral mixture, 5-10% diluent glycidyl methacrylate, 20-25% curing agent diaminodiphenylmethane (DDM), and 0.5-1% accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol).

2. The glass composite material heated bed for 3D printers according to claim 1, characterized in that: The toughening agent has a nitrile rubber nitrile value of 40, i.e., nitrile-40, and a PVB acetal value range of 10-17%. The mixing ratio of nitrile-40 to PVB is 100:(40-60).

3. The glass composite material heated bed for 3D printers according to claim 1, characterized in that: The B component, by mass percentage, comprises: 13-20% boron nitride particles, 58-65% alumina particles, 5-12% magnesium oxide particles, and 5-10% chopped glass fibers.

4. The glass composite material heated bed for 3D printers according to claim 3, characterized in that: The boron nitride nanosheets have a thickness of 100-150 nm and a length of 10-15 μm; the chopped glass fibers have a length of 3-8 mm and a diameter of 100-120 μm; the alumina particles are spherical with a diameter range of 5-20 μm; and the magnesium oxide particles are irregularly sheet-like with an approximate diameter of 5-10 μm and a thickness of 2-5 μm.

5. A glass composite material heated bed for a 3D printer according to claim 1, characterized in that: The C component, by mass percentage, comprises: 26-35% wetting and dispersing agent, 23-32% leveling agent, and 33-42% coupling agent.

6. A glass composite material heated bed for a 3D printer according to claim 5, characterized in that: The wetting and dispersing agents include BYK-20, BYK-40 or BYK-50, the leveling agents include BYK-80, BYK-120, BYK-100 or BYK-550, and the coupling agents include KH-550 or KH-560.

7. A glass composite material heated bed for a 3D printer according to claim 1, characterized in that: The D component, by mass percentage, comprises: 30-42% dimethylformamide, 25-35% ethyl acetate, and 25-35% cyclohexanone.

8. The method for preparing the thermally conductive adhesive body in a glass composite heated bed for a 3D printer as described in claim 1, characterized in that, Includes the following steps: 1) Weigh out glycidyl ether type phenolic epoxy resin F-51, glycidyl ether type phenolic epoxy resin E-20, and glycidyl ester type phenolic epoxy resin TDE-85 according to the proportions and add them to a container. Add 20-30% of the total amount of solvent in component D, seal and stir for 1-3 hours until homogeneous. Then add glycidyl methacrylate diluent to the mixed epoxy and stir continuously at room temperature for 1-2 hours. Weigh out the toughening agent nitrile rubber and PVB polyvinyl butyral mixture, add 20-30% of the total amount of solvent in component D, and stir slowly for 5-6 hours until completely dissolved. Then add the dissolved toughening agent to the mixed epoxy and stir at 400-500 rpm for 2-3 hours until completely mixed. Finally, add accelerator 2 (2,4,6-tris(dimethylaminomethyl)phenol) and stir at 300-400 rpm for 1-2 hours to obtain a homogeneous first mixture for later use. 2) Weigh out the inorganic particles and chopped fibers of component B according to the proportion, add the remaining solvent of component D, stir at low speed for 3-4 hours, then add the auxiliary agent of component C, and stir at 100-200 rpm for 8-10 hours to obtain a mixed powder dispersion. 3) Add the mixed powder dispersion obtained in step 2) to the first mixture obtained in step 1), and stir at 200-300 rpm for 12-15 hours to obtain the second mixture; dissolve the curing agent diaminodiphenylmethane (DDM) in dimethylformamide, stir slowly for 4-5 hours until completely dissolved, and then add it to the second mixture above, and stir at 200-300 rpm for 2-3 hours at room temperature.

9. A method for preparing a glass composite heated bed for a 3D printer according to any one of claims 1-8, characterized in that, include: The mixed multifunctional thermally conductive adhesive is cast onto a glass substrate and then baked in a tunnel oven at different temperature ranges. An alloy sheet with a specified resistance value is etched onto one side of a coated glass substrate and then placed in a vacuum laminator for pressing at a temperature of 220°C for 3 hours. After that, a silicone insulating layer is coated onto one side of the alloy foil circuit, and finally a glass composite heated bed for 3D printers is obtained.

10. A method for preparing a glass composite heated bed for a 3D printer according to claim 9, characterized in that, Includes the following steps: The mixed multifunctional thermally conductive adhesive is uniformly cast onto the glass substrate using a casting machine at a speed of 1-2 m / min, maintaining a coating thickness of 0.3-0.5 mm. After casting, the substrate is baked in a tunnel oven with five temperature zones: 1) room temperature - 50 degrees Celsius; 2) 50-90 degrees Celsius; 3) 90-120 degrees Celsius; 4) 120-150 degrees Celsius; 5) 150-90 degrees Celsius, with a baking speed of 2-4 m / min. An alloy foil with a specified resistance value is etched onto the adhesive-coated surface of a glass substrate and then placed in a vacuum laminator for pressing. The hot pressing temperatures are set to 90℃ for 30-50 minutes, 150℃ for 2-3 hours, 175℃ for 2-3 hours, and 200℃ for 1-2 hours. After hot pressing, the substrate is cooled to room temperature, and the adhesive-coated glass substrate is removed. Then, a layer of 107 silicone insulating layer with a thickness of 1-2 mm is coated on the alloy foil circuitry and cured at 160℃ for 5-15 minutes. Finally, a glass composite heated bed for 3D printers is obtained.