Glass frit composition, glass enamel paste and method for preparing the same, zinc oxide varistor and method for preparing the same

Abstract

The application relates to the technical field of electrotechnical ceramics, and discloses a glass powder composition, a glass glaze material and a preparation method thereof, and a zinc oxide resistor and a preparation method thereof. The glass powder composition contains, based on the total weight of the glass powder composition, 65-78 wt% of Bi2O3, 10-20 wt% of ZnO, 1-8 wt% of CuO, 1.5-7.5 wt% of SiO2, 1-5 wt% of Al2O3, 1-4 wt% of Co2O3 and 4-10 wt% of B2O3, the content of the CuO is not higher than the content of the SiO2, the ratio of the content of the B2O3 to the content of the ZnO is less than or equal to 0.5, and the sum of the contents of the Bi2O3, the ZnO and the B2O3 is not less than 85% of the total weight of the glass powder composition. The zinc oxide resistor provided by the application can effectively prevent side flashover under current impact.

Description

Technical Field

[0001] This invention relates to the field of electrical ceramics technology, specifically to glass powder compositions, glass glaze slurries and their preparation methods, and zinc oxide resistor sheets and their preparation methods. Background Technology

[0002] Zinc oxide resistors are widely used to suppress overvoltages and inrush currents in electronic or electrical equipment due to their excellent nonlinearity and energy absorption capabilities, protecting the equipment from damage and ensuring its continuous normal operation. If the sides of the zinc oxide resistor are not insulated, they are prone to surface flashover when exposed to high-amplitude voltages and currents. Adding an insulating glaze to the sides of the resistor improves its ability to withstand steep-wave high-current surges, largely solving the flashover problem. According to literature reports, there are currently three main methods for applying the side insulating glaze: dip coating, coating, and spray coating. Among these, coating is the most widely used, utilizing a coating device to roll-coat organic glazes (epoxy resin, polyimide) and inorganic glass glazes onto the sides of the resistor.

[0003] Organic glazes have poor temperature resistance and will carbonize above 150℃. Under high current impact, they are prone to separating from the zinc oxide resistor element under electrothermal effects, resulting in cracks and glaze peeling, deteriorating electrical insulation performance, and seriously affecting the current impact resistance of the resistor element or the entire surge arrester after assembly. Currently used inorganic insulating glazes have complex compositions and contain highly toxic vanadium or lead elements, which are not environmentally friendly. Although the glass glaze material itself is heat-resistant and can withstand 300-400℃, the thermal expansion coefficients of the inorganic insulating glaze differ from those of the zinc oxide resistor element and its underlying high-resistivity layer, resulting in limited matching. Under high amplitude current impact, peeling or cracking may still occur, affecting the actual insulation performance and causing surface discharge flashover.

[0004] CN113149445A discloses a method for uniformly refining low-temperature lead-free glass powder using ultra-high pressure microjets. The low-temperature lead-free glass powder comprises the following components by mass percentage: Bi₂O₃: 60.0-80.0 wt%, ZnO: 10.0-25.0 wt%, Sb₂O₃: 0.5-5.0 wt%, SiO₂: 1.0-3.0 wt%, CuO: 1.0-3.0 wt%, Al₂O₃: 0.5-3.0 wt%, Mn₃O₄: 0.1-0.8 wt%. This glass powder is free of lead and other harmful substances, making it environmentally friendly. The preparation process does not require grinding media such as ball mill beads, resulting in a simple process, short homogenization time, and high dispersion efficiency. The particles are highly uniform in size and have a narrow particle size distribution, resulting in a dense and uniform side insulating coating with excellent resistance to high-current impact. However, the use of ultra-high pressure microjets to uniformly refine low-temperature lead-free glass powder requires sophisticated equipment and is costly, making industrial application difficult at present.

[0005] CN102503582A discloses a method for preparing an inorganic-organic composite insulating coating resistant to high current surges. The method is characterized by first preparing a dense and uniform inorganic insulating coating on the surface of a resistor sheet, using raw materials including ZnO and SiO2. 2、 Al2O3, Fe2O3, and WO3 are all nanoparticles. Nano-Al2O3 is added to an organosilicon coating for modification, and then coated onto the surface of the prepared inorganic coating. Sintering is then performed to obtain the desired inorganic-organic composite insulating coating. This coating does not contain highly toxic elements, exhibits excellent overall electrical properties, high resistance to high-current impact, and strong adhesion. However, this method requires treating the inorganic coating first, followed by the organic insulating coating, making the process relatively complex.

[0006] CN102390992A discloses a resistor element for DC surge arresters, made from twelve raw materials: Bi2O3, Sb2O3, Co2O3, MnCO3, NiO, ZrO2, Al(NO3)3, B2O3, binder, dispersant, defoamer, and ZnO. This resistor element employs a novel formulation system and production process, with fewer added elements, a simpler process, and lower cost. The internal structure of the resistor element is more stable and uniform, significantly improving its aging resistance, current surge stability, thermal conductivity, square wave current capacity, and other performance characteristics. It fully meets the requirements of various DC surge arresters and is universally applicable to both AC and DC surge arresters. It features large capacity, low voltage ratio, high allowable charge rate, and sufficient safety margin. However, this prior art does not address the side insulation layer treatment process of the zinc oxide resistor element, nor does it address the impact of the side insulation layer on the surge withstand performance of the zinc oxide resistor element. Summary of the Invention

[0007] The purpose of this invention is to overcome the problem of poor resistance to high current surges in existing zinc oxide resistors.

[0008] To achieve the above objectives, a first aspect of the present invention provides a glass powder composition, wherein, based on the total weight of the glass powder composition, the glass powder composition contains: 65-78 wt% Bi₂O₃, 10-20 wt% ZnO, 1-8 wt% CuO, 1.5-7.5 wt% SiO₂, 1-5 wt% Al₂O₃, 1-4 wt% Co₂O₃, and 4-10 wt% B₂O₃, wherein the content of CuO is not higher than the content of SiO₂, the ratio of the content of B₂O₃ to the content of ZnO is less than or equal to 0.5, and the sum of the contents of Bi₂O₃, ZnO, and B₂O₃ is not less than 85% of the total weight of the glass powder composition.

[0009] A second aspect of the present invention provides a method for preparing a glass glaze slurry, the method comprising using the components of the glass powder composition described in the first aspect above, including:

[0010] S1: The glass powder composition is successively melted, quenched and ground to obtain mixture I with an average particle size of not more than 200 μm;

[0011] S2: Add adhesive to mixture I to obtain mixture II;

[0012] S3: In the presence of grinding balls, the mixture II is ball-milled to obtain the glass glaze slurry.

[0013] The third aspect of the present invention provides a glass glaze slurry prepared by the method for preparing the glass glaze slurry described in the second aspect above.

[0014] A fourth aspect of the present invention provides a method for preparing a zinc oxide resistor sheet, the method being carried out using the glass glaze slurry described in the third aspect above, comprising:

[0015] (1) Heat-treat the zinc oxide resistor blank to obtain the heat-treated zinc oxide resistor blank;

[0016] (2) Spray the glass glaze slurry onto the side of the heat-treated zinc oxide resistor blank to obtain a zinc oxide resistor blank coated with glass glaze;

[0017] (3) The zinc oxide resistor blank coated with glass glaze is subjected to a third heating treatment at a heating rate of 1-2℃ / min to T3 temperature to obtain intermediate IV, wherein the T3 temperature is 400-430℃.

[0018] (4) The intermediate IV is subjected to a fourth heating treatment at a heating rate of 0.5 to 1.5 °C / min to T4 temperature to obtain intermediate V, wherein the T4 temperature is 480-550 °C;

[0019] (5) The intermediate V is cooled to 150-200℃ at a cooling rate of 0.2-0.8℃ / min to obtain zinc oxide resistor sheet.

[0020] The fifth aspect of the present invention provides a zinc oxide resistor prepared by the method described in the fourth aspect above.

[0021] The glass powder composition provided by this invention has a relatively simple composition and is environmentally friendly and non-toxic.

[0022] The inventors of this invention have optimized the glass glaze preparation process and combined the heating stage of glass glaze formation with the heat treatment process of the zinc oxide resistance sheet itself, simplifying the process and making it suitable for mass industrial production applications.

[0023] This invention employs a combination of reasonable formulation and process to prepare a glass glaze that can bond tightly to the side of the zinc oxide resistor sheet blank, effectively improving the insulation performance of the side of the zinc oxide resistor sheet, reducing the flashover probability of the zinc oxide resistor sheet under high amplitude and high current impact, and significantly improving the ability of the zinc oxide resistor sheet to withstand high current impact. Attached Figure Description

[0024] Figure 1 This is a particle size distribution diagram of the glass glaze slurry prepared in Example 1;

[0025] Figure 2 This is a scanning electron microscope image of the glass glaze slurry prepared in Example 1 being sprayed onto the side of a zinc oxide resistor blank. Detailed Implementation

[0026] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0027] As previously described, a first aspect of the present invention provides a glass powder composition, wherein, based on the total weight of the glass powder composition, the glass powder composition contains: 65-78 wt% Bi₂O₃, 10-20 wt% ZnO, 1-8 wt% CuO, 1.5-7.5 wt% SiO₂, 1-5 wt% Al₂O₃, 1-4 wt% Co₂O₃, and 4-10 wt% B₂O₃, wherein the content of CuO is not higher than the content of SiO₂, the ratio of the content of B₂O₃ to the content of ZnO is less than or equal to 0.5, and the sum of the contents of Bi₂O₃, ZnO, and B₂O₃ is not less than 85% of the total weight of the glass powder composition.

[0028] As previously described, a second aspect of the present invention provides a method for preparing a glass glaze slurry, the method comprising using the components of the glass powder composition described in the first aspect, including:

[0029] S1: The glass powder composition is successively melted, quenched and ground to obtain mixture I with an average particle size of not more than 200 μm;

[0030] S2: Add adhesive to mixture I to obtain mixture II;

[0031] S3: In the presence of grinding balls, the mixture II is ball-milled to obtain the glass glaze slurry.

[0032] Preferably, in step S1, the smelting operation includes:

[0033] S1a: The glass powder composition is subjected to a first heating treatment at a heating rate of 1 to 3 °C / min to a temperature T1 to obtain intermediate I, wherein the temperature T1 is 600-700 °C.

[0034] S1b: The intermediate I is subjected to a second heating treatment at a heating rate of 1 to 2 °C / min to a temperature of T2 to obtain intermediate II, wherein the temperature of T2 is 1000-1100 °C;

[0035] S1c: The intermediate II is kept at the T2 temperature for 0.5 to 1.5 hours to obtain intermediate III as the product of the melting operation.

[0036] Preferably, in step S1, the quenching operation includes cooling the intermediate III to 100-200°C at a cooling rate of 10-30°C / min.

[0037] There are no special requirements for the specific grinding operation in this invention. Those skilled in the art can use operations known in the art, and this should not be construed as a limitation of this invention.

[0038] It should be noted that, in step S1, to obtain the mixture I with an average particle size of no more than 200 μm, post-processing methods such as filtration and drying can be performed after grinding. For example, the filtration can use an 80-100 mesh Chinese standard sieve to collect the undersize material.

[0039] Preferably, in step S2, the weight ratio of the mixture I to the adhesive is 1 to 1.5:1.

[0040] Preferably, the adhesive is ethyl cellulose and / or hydroxypropyl cellulose. Particularly preferably, the adhesive is hydroxypropyl cellulose.

[0041] It should be noted that the present invention does not impose any particular restrictions on the state in which the adhesive is applied. The adhesive can be applied in the form of a solution. For example, the present invention provides a preferred embodiment: the adhesive is dissolved in deionized water at a temperature of 80-90°C until it becomes transparent to obtain an adhesive solution.

[0042] Preferably, in step S3, the volume ratio of the mixture II to the grinding balls is 1 to 2:1.

[0043] Preferably, in step S3, the diameter of each of the grinding balls is independently 3mm to 10mm.

[0044] Preferably, in step S3, the ball milling is carried out in a ball mill with a rotation speed of 200-500 rpm and a milling time of 24-72 h.

[0045] It should be noted that in step S3, a filtration operation can be performed after ball milling. For example, the filtration can be performed using a 140-200 mesh Chinese standard sieve to collect the undersize material.

[0046] As previously stated, the third aspect of the present invention provides a glass glaze slurry prepared by the method for preparing the glass glaze slurry described in the second aspect.

[0047] As previously described, a fourth aspect of the present invention provides a method for preparing a zinc oxide resistor sheet, the method being carried out using the glass glaze slurry described in the third aspect above, comprising:

[0048] (1) Heat-treat the zinc oxide resistor blank to obtain the heat-treated zinc oxide resistor blank;

[0049] (2) Spray the glass glaze slurry onto the side of the heat-treated zinc oxide resistor blank to obtain a zinc oxide resistor blank coated with glass glaze;

[0050] (3) The zinc oxide resistor blank coated with glass glaze is subjected to a third heating treatment at a heating rate of 1-2℃ / min to the T3 temperature, intermediate IV, wherein the T3 temperature is 400-430℃;

[0051] (4) The intermediate IV is subjected to a fourth heating treatment at a heating rate of 0.5 to 1.5 °C / min to T4 temperature to obtain intermediate V, wherein the T4 temperature is 480-550 °C;

[0052] (5) The intermediate V is cooled to 150-200℃ at a cooling rate of 0.2-0.8℃ / min to obtain zinc oxide resistor sheet.

[0053] Preferably, in step (1), the diameter of the zinc oxide resistor blank is 32-100 mm.

[0054] Particularly preferably, in step (1), the diameter of the zinc oxide resistor blank is 42 mm.

[0055] Preferably, in step (1), the heat treatment temperature is 60-100°C and the time is 0.5-1.5h.

[0056] Preferably, in step (2), the spraying is performed using a spray gun.

[0057] Preferably, in step (2), the viscosity of the glass glaze slurry at 25°C is 1.7 to 2.3 Pa·s, and the average particle size of the glass glaze slurry is 2 to 7 μm.

[0058] Preferably, in step (2), the thickness of the spray coating is controlled between 80 and 250 μm.

[0059] It should be noted that in step (5), the zinc oxide resistor sheet can also be subjected to post-processing methods such as grinding, cleaning and spraying aluminum electrodes. These post-processing methods are all known to those skilled in the art.

[0060] As previously stated, the fifth aspect of the present invention provides a zinc oxide resistor prepared by the method for preparing zinc oxide resistors described in the fourth aspect.

[0061] The present invention will be described in detail below through examples.

[0062] In the following examples, unless otherwise specified, all instruments, reagents, and materials used are conventional and can be obtained through legitimate commercial channels. Unless otherwise stated, all reagents used are commercially available analytical grade products.

[0063] Grinding ball

[0064] Grinding balls: purchased from Changsha Miqi Instrument Equipment Co., Ltd., grade: zirconia-5mm.

[0065] adhesives

[0066] Hydroxypropyl cellulose: purchased from Sinopharm Reagent Chemical Co., Ltd., brand name XW90046423.

[0067] Zinc oxide resistor blank

[0068] Zinc oxide resistor blank: purchased from Hunan Gaoxin Fu'an Electric Technology Co., Ltd., model D42.

[0069] spray gun

[0070] Spray gun: Purchased from Anast Iwata Co., Ltd., model WIDER1A-10E2PAC.

[0071] Preparation Example 1: Preparation of Adhesive Solution

[0072] Pour deionized water into the inner tank of a water bath and heat it slowly. When the water temperature reaches 80°C, add the binder (hydroxypropyl cellulose) one by one until it is completely dissolved and becomes transparent, thus obtaining the binder solution.

[0073] Different glass powder composition formulations were used in the following examples of the present invention, and the specific glass powder composition formulations are shown in Table 1.

[0074] Table 1

[0075]

[0076] Example 1

[0077] S1: 5000g of glass powder composition is heated to temperature T1 at a first heating rate to obtain intermediate I;

[0078] S2: Intermediate I is subjected to a second heating treatment at a second heating rate to temperature T2 to obtain intermediate II;

[0079] S3: Intermediate II is kept at temperature T2 to obtain intermediate III as a product of the smelting operation;

[0080] S4: Cool intermediate III to temperature T at a cooling rate A to obtain the quenched product;

[0081] S5: Grind the quenched product, sieve it through a 100-mesh Chinese standard sieve to collect the sieve material, and dry it to obtain mixture I with an average particle size of 190μm;

[0082] S6: Add the binder (prepared as described above) to mixture I to obtain mixture II;

[0083] S7: In the presence of grinding balls, the above mixture II is ball-milled (the volume of the ball mill jar is 2L, and the grinding balls occupy one-third of the volume of the ball mill jar) to obtain the ball-milled product;

[0084] S8: The ball-milled product is sieved through a 180-mesh Chinese standard sieve to obtain the undersize material, thus obtaining glass glaze slurry J1.

[0085] The specific process parameters in this embodiment are shown in Table 2.

[0086] Unless otherwise specified, the remaining embodiments follow the same process as in Example 1, except that the glass powder composition formulation and process parameters are different, as shown in Table 2. Any parts not listed are the same as in Example 1.

[0087] Example 4

[0088] This embodiment uses the same method as Example 1. The difference is that the first heating rate in this embodiment is adjusted from 2℃ / min in Example 1 to 4℃ / min. For specific process parameters, please refer to Table 2.

[0089] The rest is the same as in Example 1, and glass glaze slurry J4 is obtained.

[0090] Example 5

[0091] This embodiment uses the same method as Example 1. The difference is that, while keeping the amount of mixture I unchanged, the weight ratio of mixture I to adhesive solution is adjusted from 1.2:1 in Example 1 to 2:1. See Table 2 for specific process parameters.

[0092] The rest is the same as in Example 1, and glass glaze slurry J5 is obtained.

[0093] Comparative Example 1

[0094] This comparative example was conducted using the same method as Example 1, except that an equal weight of comparative formulation D1 was used to replace formulation 1.

[0095] The same as in Example 1 was used to prepare glass glaze slurry DJ1.

[0096] Comparative Example 2

[0097] This comparative example was conducted using the same method as Example 1, except that an equal weight of comparative formulation D2 was used to replace formulation 1.

[0098] The same as in Example 1 was used to prepare glass glaze slurry DJ2.

[0099] Comparative Example 3

[0100] This comparative example was conducted using the same method as Example 1, except that an equal weight of comparative formulation D3 was used to replace formulation 1 in this comparative example.

[0101] The same as in Example 1 was used to prepare glass glaze slurry DJ3.

[0102] Comparative Example 4

[0103] This comparative example was conducted using the same method as Example 1, except that an equal weight of comparative formulation D4 was used to replace formulation 1 in this comparative example.

[0104] The same as in Example 1 was used to prepare glass glaze slurry DJ4.

[0105] Table 2

[0106]

[0107]

[0108] Test case A1

[0109] S1: The zinc oxide resistor blank is heat-treated (the heat treatment temperature is 80℃ and the time is 1h) to obtain the heat-treated zinc oxide resistor blank.

[0110] S2: The side of the heat-treated zinc oxide resistor blank is sprayed with the glass glaze slurry prepared in the example using a spray gun to obtain a zinc oxide resistor blank coated with glass glaze.

[0111] S3: The zinc oxide resistor blank coated with glass glaze is subjected to a third heating treatment at a heating rate of 1℃ / min to T3 temperature (T3 temperature is 400℃) to obtain intermediate IV;

[0112] S4: Intermediate IV is subjected to a fourth heating treatment at a heating rate of 1℃ / min to T4 temperature (T4 temperature is 525℃) to obtain intermediate V;

[0113] S5: After cooling intermediate V to T5 temperature (T5 temperature is 200℃) at a cooling rate of 0.6℃ / min, perform grinding, cleaning and aluminum electrode spraying treatment (the same method as in Example 1 of CN110156454A can be referred to) to obtain zinc oxide resistor sheet.

[0114] The specific process parameters for this test case are shown in Table 3.

[0115] Unless otherwise specified, the remaining test cases were conducted using the same method as test case A1, except for the different raw materials and process parameters, as shown in Table 3. All other parts not listed are the same as those in test case A1.

[0116] Table 3

[0117] Test case A1 Test case A2 Test case A3 Heat treatment Temperature / °C 80 60 100 Time / h 1 1.5 0.5 Third heating process Third heating rate (°C / min) 1 2 1.5 T3 400 410 430 Fourth heating process Fourth heating rate (°C / min) 1 0.5 1.5 T4 525 550 500 Cooling treatment Cooling rate (°C / min) 0.6 0.2 0.8 T5 200 170 150 Coating thickness / μm 155-165 225-235 80-90

[0118] Test Case B

[0119] The current impact performance of the zinc oxide resistor was tested using the 4 / 10μs high current impact method according to the GB / T11032-2020 standard. The test results are shown in Table 4.

[0120] Table 4

[0121] Source of glass glaze slurry Test Case A Maximum withstand capability for 4 / 10μs current surge (kA) Example 1 A1 120 Example 2 A1 117 Example 3 A1 113 Example 4 A1 110 Example 5 A1 107 Comparative Example 1 A1 93 Comparative Example 2 A1 94 Comparative Example 3 A1 91 Comparative Example 4 A1 87 Example 1 A2 112 Example 2 A2 114 Comparative Example 1 A2 94 Example 1 A3 115 Example 2 A3 111 Comparative Example 1 A3 91

[0122] The results above show that the zinc oxide resistor sheet prepared using the glass glaze slurry of the present invention has a withstand value of >100kA under a 4 / 10μs current impact, indicating that the zinc oxide resistor sheet prepared using the glass glaze slurry of the present invention in combination with the method of the present invention has excellent resistance to high current impact.

[0123] In addition, the present invention provides, by way of example, a particle size distribution diagram of the glass glaze slurry obtained in Example 1, such as... Figure 1 As shown, from Figure 1 As can be seen from the data, the glass glaze slurry has fine particles with a Gaussian particle size distribution, and the particle size is mainly concentrated in the range of 2 to 7 μm. This is beneficial for the glass glaze slurry particles to adhere more evenly to the side of the zinc oxide resistor sheet blank during spraying.

[0124] The present invention provides, exemplarily, scanning electron microscope (SEM) images of the glass glaze slurry obtained in Example 1 after being sprayed onto the side of a zinc oxide resistor sheet blank and subjected to heating and cooling treatments, as shown below. Figure 2 As shown, from Figure 2 As can be seen, the thickness of the glass glaze layer formed on the side of the zinc oxide resistor is relatively uniform, and the glass glaze layer is tightly bonded to the side of the zinc oxide resistor blank. Under current impact, the zinc oxide resistor is not prone to side flashover, which is beneficial to the current impact withstand capability of the zinc oxide resistor.

[0125] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A glass powder composition, characterized in that, Based on the total weight of the glass powder composition, the glass powder composition contains: 66-76 wt% Bi2O3, 12-15 wt% ZnO, 2-8 wt% CuO, 3.5-4.5 wt% SiO2, 1.5-5 wt% Al2O3, 1-3 wt% Co2O3 and 4-7 wt% B2O3, wherein the content of CuO is not higher than the content of SiO2, the ratio of the content of B2O3 to the content of ZnO is less than or equal to 0.5, and the sum of the contents of Bi2O3, ZnO and B2O3 is not less than 85% of the total weight of the glass powder composition.

2. A method for preparing a glass glaze slurry, characterized in that, This method utilizes the components of the glass powder composition described in claim 1, including: S1: The glass powder composition is successively melted, quenched and ground to obtain a mixture I with an average particle size of not more than 200 μm; S2: Add adhesive to mixture I to obtain mixture II; S3: In the presence of grinding balls, the mixture II is ball-milled to obtain the glass glaze slurry.

3. The method for preparing glass glaze slurry according to claim 2, wherein, In step S1, the smelting operation includes: S1a: The glass powder composition is subjected to a first heating treatment at a heating rate of 1~3℃ / min to a temperature T1 to obtain intermediate I, wherein the temperature T1 is 600-700℃; S1b: The intermediate I is subjected to a second heating treatment at a heating rate of 1~2℃ / min to T2 temperature to obtain intermediate II, wherein the T2 temperature is 1000-1100℃; S1c: The intermediate II is kept at the T2 temperature for 0.5~1.5h to obtain intermediate III as the product of the melting operation.

4. The method for preparing glass glaze slurry according to claim 2 or 3, wherein, In step S1, the quenching operation includes cooling the intermediate III to 100-200°C at a cooling rate of 10-30°C / min.

5. The method for preparing glass glaze slurry according to claim 2 or 3, wherein, In step S2, the weight ratio of the mixture I to the adhesive is 1~1.5:1; And / or, the adhesive is hydroxypropyl cellulose.

6. The method for preparing glass glaze slurry according to claim 2 or 3, wherein, In step S3, the volume ratio of the mixture II to the grinding balls is 1~2:1; And / or, the diameter of each of the grinding balls is independently 3mm to 10mm; And / or, the ball milling is carried out in a ball mill with a rotation speed of 200~500 rpm and a milling time of 24~72 h.

7. A glass glaze slurry prepared by the method for preparing glass glaze slurry according to any one of claims 2-6.

8. A method for preparing a zinc oxide resistor sheet, characterized in that, This method uses the glass glaze slurry described in claim 7, and includes: (1) Heat-treat the zinc oxide resistor blank to obtain the heat-treated zinc oxide resistor blank; (2) Spray the glass glaze slurry onto the side of the heat-treated zinc oxide resistor blank to obtain a zinc oxide resistor blank coated with glass glaze; (3) The zinc oxide resistive sheet blank coated with glass glaze is subjected to a third heating treatment at a heating rate of 1~2℃ / min to T3 temperature to obtain intermediate IV, wherein the T3 temperature is 400-430℃; (4) The intermediate IV is subjected to a fourth heating treatment at a heating rate of 0.5~1.5℃ / min to T4 temperature to obtain intermediate V, wherein the T4 temperature is 480-550℃; (5) The intermediate V is cooled to 150-200℃ at a cooling rate of 0.2~0.8℃ / min to obtain zinc oxide resistor sheet.

9. The method for preparing zinc oxide resistors according to claim 8, wherein, In step (1), the heat treatment temperature is 60~100℃ and the time is 0.5~1.5h; And / or, in step (2), the thickness of the spray coating is controlled to be 80~250μm.

10. A zinc oxide resistor prepared by the method for preparing zinc oxide resistors according to claim 8 or 9.

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