Electric heating plate and method for preparing coating of high temperature resistant heat conductive insulating protective coating

Abstract

The present invention relates to an electric heating plate, which comprises a high-temperature heat-conducting plate, a graphene heating coating and a conductive electrode coating, wherein the high-temperature heat-conducting plate is coated with a graphene heating coating, and the graphene heating coating is coated with a conductive electrode coating and a high-temperature heat-conducting insulating protective coating in sequence, the graphene heating coating and the conductive electrode coating are electrically connected, the high-temperature heat-conducting insulating protective coating covers the graphene heating coating and the portion where the conductive electrode coating is connected to the graphene heating coating, and the high-temperature heat-conducting plate is provided with an elastic conductive terminal, and a portion of the conductive electrode coating exposed outside the high-temperature heat-conducting insulating protective coating is in close contact with the elastic conductive terminal. The graphene heating coating is coated with a high-temperature heat-conducting insulating protective coating, and the high-temperature heat-conducting insulating protective coating covers the graphene heating coating and the portion where the conductive electrode coating is connected to the graphene heating coating, which can prevent the graphene heating coating from oxidizing and decaying, and extend the life of the graphene heating coating.

Description

Technical Field

[0001] The invention relates to an electric heating plate and a method for preparing a coating material of a high-temperature resistant heat-conductive insulating protective coating of the electric heating plate. Background Art

[0002] The existing electric heating plate adopts a microcrystalline glass plate or a mica sheet with one end surface coated with a graphene heating coating, and the graphene heating coating is coated with a conductive electrode coating. The conductive electrode coating and the graphene heating coating are electrically connected. The power is transferred to the graphene heating coating through the conductive electrode coating. The heat generated by the graphene heating coating is transferred to the microcrystalline glass plate or mica sheet, thereby making the microcrystalline glass plate or mica sheet generate high temperature for cooking food or heating.

[0003] Since the microcrystalline glass plate is resistant to high temperatures (can withstand high temperatures of 900°C) and has excellent vertical thermal conductivity, the heat generated by the graphene heating coating is directly transferred to the microcrystalline glass plate. The microcrystalline glass plate transfers the heat to the heated object, with less heat loss and high energy conversion efficiency. At the same time, the microcrystalline glass plate has good insulation properties and is safer to use.

[0004] However, the graphene heating coating of the existing electric heating plate is directly exposed to the air, and there is no protective coating on the surface of the graphene heating coating. The graphene heating coating is easily corroded by oxidation or corrosive gases, which causes the heating effect of the graphene heating coating to easily decay, reducing the service life of the graphene heating coating. Moreover, the graphene heating coating is exposed to the outside world, which is prone to the risk of electric shock.

[0005] In addition, there is now a graphene heating coating coated on the heat-conducting plate, and a conductive electrode coating coated on the graphene heating coating, which is mainly used in situations where the heating temperature is not high. The conductive electrode coating and the conductive terminal are generally connected by soldering. When it is needed in situations where high-temperature heating is required, the conductive electrode coating and the conductive terminal are easily desoldered when connected by soldering. Summary of the invention

[0006] The first purpose of the present invention is to provide an electric heating plate that effectively extends the life of the graphene heating coating and is resistant to high temperatures, has good thermal conductivity, good insulation effect, and stable and reliable conductive terminals.

[0007] The second object of the present invention is to provide a method for preparing a coating for a high-temperature resistant, thermally conductive, insulating protective coating.

[0008] The first object of the present invention is achieved by:

[0009] An electric heating plate comprises a high-temperature heat-conducting plate, a graphene heating coating and a conductive electrode coating, wherein the high-temperature heat-conducting plate is coated with the graphene heating coating, the conductive electrode coating and the high-temperature heat-conducting insulating protective coating are coated on the graphene heating coating in sequence, the graphene heating coating and the conductive electrode coating are electrically connected, the high-temperature heat-conducting insulating protective coating covers the graphene heating coating and the portion where the conductive electrode coating is connected to the graphene heating coating, an elastic conductive terminal is provided on the high-temperature heat-conducting plate, and a portion of the conductive electrode coating exposed outside the high-temperature heat-conducting insulating protective coating is in close contact with the elastic conductive terminal.

[0010] The graphene heating coating is coated with a high-temperature resistant thermally conductive insulating protective coating, which covers the graphene heating coating and the portion where the conductive electrode coating is connected to the graphene heating coating, thereby preventing oxidation and decay of the graphene heating coating and extending the life of the graphene heating coating. The high-temperature resistant thermally conductive insulating protective coating has the functions of high-temperature resistance, thermal conductivity, and insulation, thereby avoiding leakage caused by the conductive electrode coating and the graphene heating coating contacting metal objects when the electric heating plate is installed or used, thereby greatly improving the safety of the electric heating plate.

[0011] The first object of the present invention can also be solved by the following technical measures:

[0012] As a more specific solution, the high-temperature heat-conducting plate is coated with a high-temperature resistant heat-conducting insulating protective coating, and the graphene heating coating is coated on the high-temperature resistant heat-conducting insulating protective coating.

[0013] Coating a high-temperature resistant thermally conductive insulating protective coating on the high-temperature heat conductive plate can significantly enhance the high-temperature resistance, thermal conductivity and insulation performance of the high-temperature heat conductive plate.

[0014] As a more specific solution, the high-temperature heat-conducting plate is a microcrystalline glass plate or a ceramic plate. The microcrystalline glass plate has high temperature resistance (can withstand high temperatures of 900°C) and excellent vertical thermal conductivity, so the heat generated by the graphene heating coating is directly transferred to the microcrystalline glass plate, and the microcrystalline glass plate transfers the heat to the heated object, with less heat loss and high energy conversion efficiency. At the same time, the microcrystalline glass plate has good insulation properties and is safer to use.

[0015] As a more specific solution, the high-temperature heat-conducting plate is a metal heat-conducting plate coated with a high-temperature heat-conducting insulating protective coating, such as an aluminum plate or a stainless steel plate. The metal plate has a good thermal conductivity. By coating the metal heat-conducting plate with a high-temperature heat-conducting insulating protective coating, the metal heat-conducting plate can have a good thermal conductivity and good high-temperature resistance and insulation performance, which greatly increases the selection range of the high-temperature heat-conducting plate. The high-temperature heat-conducting insulating protective coating can also be coated on other heating appliances, and then the graphene heating coating is coated with the high-temperature heat-conducting insulating protective coating to directly heat the heating appliance, which has a wider range of applications.

[0016] As a more specific solution, the elastic conductive terminal includes a high temperature resistant insulating clamp and an elastic conductive sheet. The high temperature resistant insulating clamp has a clamping opening. The elastic conductive sheet is arranged in the high temperature resistant insulating clamp. One end of the elastic conductive sheet faces the clamping opening, and the other end of the elastic conductive sheet extends out of the high temperature resistant insulating clamp to connect to a power source.

[0017] As a more specific solution, the high temperature heat conductive plate is inserted into the clamping opening of the high temperature resistant insulating clamp, and the end of the elastic conductive sheet facing the clamping opening is a U-shaped elastic conductive portion, and the U-shaped elastic conductive portion is in close contact with the conductive electrode coating.

[0018] As a more specific solution, the U-shaped elastic conductive part is provided with a silver contact, and the silver contact is in close contact with the conductive electrode coating, so the conductive performance is better and the conductive terminal connection is stable and reliable.

[0019] As a more specific solution, the conductive electrode coating is a composite silver coating or a composite copper coating.

[0020] As a more specific solution, the coating components of the high-temperature resistant thermally conductive insulating protective coating include water, phosphorus pentoxide, magnesium hydroxide, silicon oxide, aluminum oxide, silica sol, ethanol, a cross-linking agent, a defoaming agent and boric acid.

[0021] The second object of the present invention is achieved by:

[0022] The coating preparation method of the high temperature resistant thermal conductive insulating protective coating:

[0023] Step 1: Mix 15% water and 85% phosphorus pentoxide powder, heat to 50-60°C, and stir evenly to obtain a phosphoric acid solution.

[0024] Step 2: Stir and mix 18% magnesium hydroxide powder and 82% phosphoric acid solution, heat to boiling state until it becomes transparent, and then cool to 15-25°C to obtain magnesium phosphate solution.

[0025] Step 3: Mix 26% magnesium phosphate solution, 5% silicon oxide powder, 18% aluminum oxide powder, 24% silica sol, 25% ethanol solution (75% industrial alcohol), 1% cross-linking agent powder, 0.3% defoaming agent and 0.7% boric acid powder by ball milling to obtain high-temperature resistant thermally conductive insulating coating.

[0026] The beneficial effects of the present invention are as follows:

[0027] According to the present invention, the graphene heating coating is coated with a high-temperature resistant thermally conductive insulating protective coating, which covers the graphene heating coating and the portion where the conductive electrode coating is connected to the graphene heating coating, thereby preventing the graphene heating coating from oxidative decay and extending the life of the graphene heating coating. Moreover, the high-temperature resistant thermally conductive insulating protective coating has the functions of high-temperature resistance, thermal conductivity and insulation, thereby avoiding leakage caused by the conductive electrode coating and the graphene heating coating contacting metal objects when the electric heating plate is installed or used, thereby greatly improving the safety of the electric heating plate.

[0028] The present invention coats a high-temperature resistant thermally conductive insulating protective coating on a metal heat-conducting plate, so that the metal heat-conducting plate can have a good thermal conductivity effect and good high-temperature resistance and insulation performance, which greatly increases the selection range of high-temperature heat-conducting plates. The high-temperature resistant thermally conductive insulating protective coating can also be coated on other heating devices, and then the graphene heating coating is coated with the high-temperature resistant thermally conductive insulating protective coating to directly heat the heating device, which has a wider range of applications.

[0029] The present invention has better conductive performance and stable and reliable conductive terminals. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of an electric heating plate.

[0031] Figure 2 It is a schematic diagram of the exploded view of the electric heating plate.

[0032] Figure 3 It is a schematic diagram of the exploded cross-section of the electric heating plate.

[0033] Figure 4 for Figure 3 A magnified view of part A. DETAILED DESCRIPTION

[0034] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0035] Example, combined with Figures 1 to 4 As shown, an electric heating plate includes a high-temperature thermally conductive plate 1 and an elastic conductive terminal 2, wherein the high-temperature thermally conductive plate 1 is coated with a graphene heating coating 4, and the graphene heating coating 4 is coated with a conductive electrode coating 5 and a high-temperature thermally conductive insulating protective coating 3 in sequence, the graphene heating coating 4 and the conductive electrode coating 5 are electrically connected, the high-temperature thermally conductive insulating protective coating 3 covers the graphene heating coating 4 and the portion where the conductive electrode coating 5 is connected to the graphene heating coating 4, and a portion of the conductive electrode coating 5 exposed outside the high-temperature thermally conductive insulating protective coating 3 is in close contact with the elastic conductive terminal 2.

[0036] The elastic conductive terminal 2 includes a high temperature resistant insulating clip 6 and an elastic conductive sheet 7. The high temperature resistant insulating clip 6 has a clamping opening 61. The upper and lower end surfaces of the clamping opening 61 are spaced apart with grooves 62 for enhancing the friction of the clamping opening 61. The elastic conductive sheet 7 is arranged in the high temperature resistant insulating clip 6. One end of the elastic conductive sheet 7 facing the clamping opening 61 is a U-shaped elastic conductive portion 71. The U-shaped elastic conductive portion 71 is provided with a silver contact. The silver contact is in close contact with the conductive electrode coating 5. The other end of the elastic conductive sheet 7 extends out of the high temperature resistant insulating clip 6 to connect to a power source.

[0037] The high temperature heat conductive plate 1 is inserted into the clamping opening 61 of the elastic conductive terminal 2 so that the elastic conductive terminal 2 clamps the high temperature heat conductive plate 1 , and the U-shaped elastic conductive portion 71 is in close contact with the conductive electrode coating 5 exposed outside the high temperature heat conductive insulating protective coating 3 .

[0038] The conductive electrode coating 5 is a composite silver coating or a composite copper coating.

[0039] The high-temperature heat-conducting plate 1 is a microcrystalline glass plate, a ceramic plate or a metal heat-conducting plate, and a high-temperature resistant heat-conducting insulating protective coating 3 is coated on the high-temperature heat-conducting plate 1.

[0040] The coating components of a high-temperature resistant heat-conductive insulating protective coating 3 of an electric heating plate include: water, phosphorus pentoxide, magnesium hydroxide, silicon oxide, aluminum oxide, silica sol, ethanol, a cross-linking agent, a defoaming agent and boric acid.

[0041] The coating preparation method of the high temperature resistant thermal conductive insulating protective coating:

[0042] Step 1: Mix 15% water and 85% phosphorus pentoxide powder, heat to 50-60°C, and stir evenly to obtain a phosphoric acid solution.

[0043] Step 2: Stir and mix 18% magnesium hydroxide powder and 82% phosphoric acid solution, and heat to boiling state until it becomes transparent, then let it stand and cool to 15-25°C to obtain magnesium phosphate solution.

[0044] Step 3: Mix 26% magnesium phosphate solution, 5% silicon oxide powder, 18% aluminum oxide powder, 24% silica sol, 25% ethanol solution (75% industrial alcohol), 1% cross-linking agent powder, 0.3% defoaming agent and 0.7% boric acid powder by ball milling to obtain a high-temperature resistant thermally conductive insulating coating with a temperature resistance of more than 1000°C.

[0045] The high-temperature heat-conducting plate 1 of the present invention is not limited to microcrystalline glass plates or ceramic plates, but includes any metal heat-conducting plate with thermal conductivity. The present invention applies a layer of high-temperature resistant heat-conducting insulating protective coating 3 on the metal heat-conducting plate to make the metal plate a high-temperature heat-conducting plate 1 with high temperature resistance, good thermal conductivity and good insulation effect. Therefore, any high-temperature heat-conducting insulating protective coating 3 applied to the high-temperature heat-conducting plate 1 or heating device, and then coating the graphene heating coating 4 on the high-temperature heat-conducting insulating protective coating 3, all fall within the protection scope of the present invention.

Claims

1. An electric heating plate, comprising a high-temperature heat-conducting plate, a graphene heating coating and a conductive electrode coating, characterized in that: The high-temperature heat-conducting plate is coated with a graphene heating coating, and a conductive electrode coating and a high-temperature heat-conducting insulating protective coating are sequentially coated on the graphene heating coating, the graphene heating coating and the conductive electrode coating are electrically connected, the high-temperature heat-conducting insulating protective coating covers the graphene heating coating and the portion where the conductive electrode coating is connected to the graphene heating coating, and an elastic conductive terminal is provided on the high-temperature heat-conducting plate, and a portion of the conductive electrode coating exposed outside the high-temperature heat-conducting insulating protective coating is in close contact with the elastic conductive terminal; The coating components of the high-temperature resistant thermal conductive insulating protective coating include water, phosphorus pentoxide, magnesium hydroxide, silicon oxide, aluminum oxide, silica sol, ethanol, a cross-linking agent, a defoaming agent and boric acid; A method for preparing the coating of the high temperature resistant heat conductive insulating protective coating of the electric heating plate, The following steps are included: Step 1: Mix 15% water and 85% phosphorus pentoxide powder, heat to 50-60°C, and stir evenly to obtain a phosphoric acid solution; Step 2: Stir and mix 18% magnesium hydroxide powder and 82% phosphoric acid solution, heat to boiling state until it becomes transparent, and then cool to 15-25°C to obtain magnesium phosphate solution; Step 3: Mix 26% magnesium phosphate solution, 5% silicon oxide powder, 18% aluminum oxide powder, 24% silica sol, 25% ethanol solution (75% industrial alcohol), 1% cross-linking agent powder, 0.3% defoaming agent and 0.7% boric acid powder by ball milling to obtain high-temperature resistant thermally conductive insulating coating.

2. The electric heating plate according to claim 1, characterized in that: The high-temperature heat-conducting plate is coated with a high-temperature resistant heat-conducting insulating protective coating, and the graphene heating coating is coated on the high-temperature resistant heat-conducting insulating protective coating.

3. The electric heating plate according to claim 1, characterized in that: The high-temperature heat-conducting plate is a glass-ceramic plate or a ceramic plate.

4. The electric heating plate according to claim 1 or 2, characterized in that: The high-temperature heat-conducting plate is a metal heat-conducting plate coated with a high-temperature resistant heat-conducting insulating protective coating.

5. The electric heating plate according to claim 1, characterized in that: The elastic conductive terminal includes a high temperature resistant insulating clip and an elastic conductive sheet. The high temperature resistant insulating clip has a clamping opening. The elastic conductive sheet is arranged in the high temperature resistant insulating clip. One end of the elastic conductive sheet faces the clamping opening, and the other end of the elastic conductive sheet extends out of the high temperature resistant insulating clip to connect to a power source.

6. The electric heating plate according to claim 5, characterized in that: The high temperature heat conductive plate is inserted into the clamping opening of the high temperature resistant insulating clamp, and the end of the elastic conductive sheet facing the clamping opening is a U-shaped elastic conductive portion. The U-shaped elastic conductive part is in close contact with the conductive electrode coating.

7. The electric heating plate according to claim 6, characterized in that: The U-shaped elastic conductive part is provided with a silver contact, and the silver contact is in close contact with the conductive electrode coating.

8. The electric heating plate according to claim 1, characterized in that: The conductive electrode coating is a composite silver coating or a composite copper coating.

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