Ceramic non-stick coating and preparation method therefor, and non-stick pan and preparation method therefor

Abstract

Provided are a ceramic non-stick coating and a preparation method therefor, and a non-stick pan and a preparation method therefor. The ceramic non-stick coating comprises a ceramic coating and a montmorillonite additive dispersed in the ceramic coating, wherein the montmorillonite additive comprises at least one of montmorillonite and modified montmorillonite. The weight of the montmorillonite additive is 5-20 wt% on the basis of the total weight of the ceramic non-stick coating, wherein the montmorillonite has a particle size of 6.5 μm to 25 μm and can have a thermal expansion ratio of 0.5-2, and the modified montmorillonite has a structure of silicone oil binding with montmorillonite. A non-stick pan prepared from the ceramic non-stick coating of the present application has a good lasting non-stickiness.

Description

[0001] TECHNICAL FIELD The present invention relates to the field of cookware, and more specifically, to a ceramic non-stick coating, a method for preparing non-stick cookware using the ceramic non-stick coating, and non-stick cookware containing the ceramic non-stick coating. Background Art Existing non-stick technologies for cookware typically involve spraying a ceramic coating (e.g., a polysiloxane ceramic coating) onto the surface of the metal substrate of the cookware, thereby achieving a non-stick effect. For example, in the process of preparing a polysiloxane ceramic coating using methyltriethoxysilane (MTES) and tetraethyl orthosilicate (TEOS) as precursors, as shown in FIG1 , a SiO sol with hydrophobic groups -CH and hydrophilic groups -OH on its surface is prepared by controlling the process according to the different hydrolysis rates of the two precursors. Upon aging of the SiO sol, the nano-SiO spontaneously clusters due to self-assembly, forming SiO particles with a nano-micrometer multi-level rough structure. The multiple nano-micrometer multi-level rough SiO particles form a lotus leaf-like structure, thus exhibiting excellent non-stick properties. However, the aforementioned lotus leaf-like structure is easily damaged (e.g., by abrasion from food during cooking or by a rag, scouring pad, or steel wool during cookware cleaning), resulting in the coating's surface roughness being destroyed, which in turn reduces its non-stick properties. In other words, even without special reinforcement, the surface roughness of existing non-stick coatings formed by ceramic coatings is easily damaged, which in turn reduces the coating's non-stick properties. SUMMARY OF THE INVENTION An object of the present invention is to provide a ceramic non-stick coating that utilizes the pore structure and thermal expansion properties of montmorillonite and / or modified montmorillonite to improve its non-stick properties. Another object of the present invention is to provide a method for preparing non-stick cookware using the ceramic non-stick coating. This method, by spraying the ceramic non-stick coating twice, can form more montmorillonite on the coating's surface, thereby improving the coating's non-stick properties. Yet another object of the present invention is to provide a non-stick cookware comprising a non-stick coating comprising the aforementioned ceramic non-stick coating, which exhibits both excellent initial non-stick properties and long-lasting non-stick properties.According to one aspect of the present invention, a ceramic non-stick coating is provided. The ceramic non-stick coating includes a ceramic coating and a montmorillonite additive dispersed in the ceramic coating. The montmorillonite additive comprises at least one of montmorillonite and modified montmorillonite. The montmorillonite additive comprises 5% to 20% by weight of the total weight of the ceramic non-stick coating. The montmorillonite has a particle size of 6.5 μm to 25 μm, and the modified montmorillonite comprises silicone oil bound to the montmorillonite. The montmorillonite may have a thermal expansion ratio of 0.5-2. In the modified montmorillonite, the weight of the silicone oil is less than or equal to 5 times the weight of the montmorillonite. According to another aspect of the present invention, a method for preparing the ceramic non-stick coating is provided. The method comprises: separately providing a ceramic coating and a montmorillonite additive; and mixing and rolling the ceramic coating and the montmorillonite additive to obtain the ceramic non-stick coating. The step of providing a montmorillonite additive includes: providing montmorillonite; and immersing at least a portion of the montmorillonite in a silicone oil solution so that the silicone oil is combined with the montmorillonite to obtain a modified montmorillonite. The concentration of the silicone oil in the silicone oil solution is not higher than 60 wt%. o The step of preparing modified montmorillonite may further include ultrasonically treating the montmorillonite bonded with silicone oil. According to another aspect of the present invention, a ceramic coating is provided. The ceramic coating is formed using a ceramic non-stick coating, the ceramic coating having surface protrusions, and the height of the surface protrusions is less than half the particle size of the montmorillonite additive. According to another aspect of the present invention, a non-stick cookware is provided. The non-stick cookware includes a substrate and a ceramic coating disposed on the substrate. According to yet another aspect of the present invention, a method for preparing non-stick cookware using a ceramic non-stick coating is provided. The method comprises: spraying the ceramic non-stick coating onto the surface of a substrate; surface-drying the substrate sprayed with the ceramic non-stick coating; and sintering the substrate sprayed with the ceramic non-stick coating to prepare the non-stick cookware. The step of spraying the ceramic non-stick coating comprises: spraying a first portion of the ceramic non-stick coating to form a bottom layer; and spraying the remaining portion of the ceramic non-stick coating to form a top layer, wherein the first portion of the ceramic non-stick coating accounts for 30% to 40% by weight of the total weight of the ceramic non-stick coating. oThe surface drying step includes preheating at 80-120°C for 3-5 minutes. BRIEF DESCRIPTION OF THE DRAWINGS FIG1 is a schematic diagram illustrating the non-stick mechanism of a prior art ceramic non-stick coating. FIG2 is a schematic diagram illustrating a non-stick coating prepared using a polymethylsiloxane ceramic coating. FIG3 is a schematic diagram illustrating a non-stick coating prepared using the ceramic non-stick coating of the present application. FIG4 is a schematic diagram illustrating the surface of a non-stick coating formed by spraying the ceramic non-stick coating once. FIG5 is a schematic diagram illustrating the surface of a non-stick coating formed by spraying the ceramic non-stick coating twice according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described more fully below with reference to exemplary embodiments. However, the present invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art. The ceramic non-stick coating of the present application will be described in detail below. In the embodiments of the present application, the ceramic non-stick coating may include a ceramic coating and a montmorillonite additive. The ceramic coating may be a ceramic coating commonly used in the art. For example, the ceramic coating may include a polysiloxane ceramic coating. For example, polysiloxane ceramic coatings may include polymethylsiloxane ceramic coatings, polydimethylsiloxane ceramic coatings, and polymethylphenylsiloxane ceramic coatings. However, exemplary embodiments are not limited thereto, and those skilled in the art may select a ceramic coating with appropriate composition based on the present inventive concept as the ceramic coating in the ceramic non-stick coating of the present inventive concept. A montmorillonite additive may be uniformly dispersed in the ceramic coating as an added component. The montmorillonite additive may include at least one of montmorillonite and modified montmorillonite. Montmorillonite has a porous structure, exhibits strong adsorption properties, and its internal pores expand when heated.When a ceramic non-stick coating containing montmorillonite is sprayed onto the surface of a cookware substrate to form a non-stick coating, on the one hand, the montmorillonite's internal pores expand upon heating, changing the coating's structure and increasing the surface protrusions, thereby enhancing the coating's non-stick properties. Furthermore, the ceramic non-stick coating can form a lotus leaf-like coating structure, providing non-stick properties. Furthermore, upon heating, the montmorillonite's internal pores expand, absorbing grease from cooking, ensuring a certain amount of grease remains on the coating surface during use, providing excellent non-stick properties. Based on the aforementioned structure of montmorillonite, the present invention also allows for modification of the montmorillonite with silicone oil to produce modified montmorillonite, further enhancing the long-lasting non-stick properties of the coating. In other words, the montmorillonite in the modified montmorillonite in the montmorillonite additive is the same montmorillonite as the montmorillonite in the montmorillonite additive, i.e., both are montmorillonite with the aforementioned structure. For example, modified montmorillonite can be prepared using the following method: Montmorillonite is immersed in a silicone oil solution for 5-30 minutes to allow the silicone oil to bind to the montmorillonite (e.g., through physical absorption or adsorption) to prepare the modified montmorillonite. Preferably, ultrasonic treatment can be performed to further bond the silicone oil to the montmorillonite. The silicone oil solution can include silicone oil and a solvent. The silicone oil can be selected from at least one of methyl silicone oil, dimethyl silicone oil, hydroxy silicone oil, hydrogenated silicone oil, and polyol-modified silicone oil, while the solvent can include at least one of xylene, ethyl acetate, and tetrahydrofuran. Furthermore, the weight content of the silicone oil, based on the total weight of the silicone oil solution, can be less than or equal to 60 wt%, for example, less than or equal to 50 wt% or less than or equal to 40 wt%. oIf the weight content of silicone oil exceeds 60wt%, the viscosity of the silicone oil solution is too high, making it difficult for the montmorillonite to absorb the silicone oil. In the embodiments of the present application, montmorillonite is modified to obtain modified montmorillonite, which combines montmorillonite with silicone oil. In the modified montmorillonite, the weight of the silicone oil can be less than or equal to 5 times the weight of the montmorillonite. For example, the weight of the silicone oil can be 2-4 times the weight of the montmorillonite, preferably 3 times. If the weight of the silicone oil is greater than 5 times the weight of the montmorillonite, the surface of the resulting coating will feel too greasy, affecting the user's experience. In the embodiments of the present application, because silicone oil has excellent non-stick properties, it can further enhance the non-stick properties of the montmorillonite when absorbed into its pores. Therefore, in the embodiments of the present application, the ceramic non-stick coating may include a ceramic material as the matrix material and may further include at least one of montmorillonite and modified montmorillonite as a montmorillonite additive. In the ceramic non-stick coating of the present application, the weight of the montmorillonite additive (i.e., montmorillonite and / or modified montmorillonite) can be 5 wt% to 20 wt% (e.g., 8 wt% to 18 wt%, 10 wt% to 16 wt%, 11 wt% to 15 wt%, or 12 wt% to 14 wt%) based on the total weight of the ceramic non-stick coating. If the weight of the montmorillonite additive is less than 5 wt%, the improvement in long-lasting non-stick properties is not significant; if the weight of the montmorillonite additive is greater than 20 wt%, the wear resistance of the coating is reduced. In embodiments of the present application, the montmorillonite can have a density of 6.5 μm to 25 μm (e.g., 8 μm to 20 μm), 10 μm to 18 μm, or 12 μm). The particle size of montmorillonite can be 0.5-2

[0002] The thermal expansion ratio of montmorillonite can be defined as the multiple by which its volume expands when heated. For example, if the volume of montmorillonite before heating is 1 and the volume after heating is 1.5, the thermal expansion ratio of montmorillonite is 0.5. The thermal expansion ratio of montmorillonite is related to its particle size. The smaller the particle size, the greater the thermal expansion ratio; conversely, the larger the particle size, the smaller the thermal expansion ratio. In the embodiments of the present application, the volume of montmorillonite increases when heated. On the one hand, this volume increase can increase its internal pores, enhance grease adsorption, and improve its non-stick properties. On the other hand, the volume increase can further increase the protrusions of the coating, thereby improving its non-stick properties. If the montmorillonite particle size is larger than 25 μm, the excessive size reduces the smoothness of the coating surface, adversely affecting the coating's aesthetics. If the montmorillonite particle size is smaller than 6.5 μm, the volume expands excessively when heated (the thermal expansion ratio is greater than 2), easily damaging the montmorillonite. In the embodiments of the present application, given a constant weight content of the montmorillonite additive in the ceramic non-stick coating, the smaller the particle size of the montmorillonite additive, the greater the content of the montmorillonite additive powder particles in the ceramic non-stick coating. Consequently, the resulting non-stick coating has a higher content of the montmorillonite additive on the coating surface, resulting in better non-stick properties. However, a higher content of the montmorillonite additive on the coating surface can deteriorate the coating's wear resistance. Conversely, given a constant weight content of the montmorillonite additive in a ceramic non-stick coating, the larger the particle size of the montmorillonite additive, the lower the content of the montmorillonite additive powder particles in the ceramic non-stick coating. Consequently, the resulting non-stick coating has a lower content of the montmorillonite additive on the coating surface, resulting in higher wear resistance. However, a lower content of the montmorillonite additive on the coating surface can deteriorate the non-stick properties of the coating. Therefore, to balance the wear resistance and non-stick properties of the non-stick coating, in an embodiment of the present application, the montmorillonite particle size can be controlled to be within a range of 6.5 μm to 25 μm. In an embodiment of the present application, a method for preparing a ceramic non-stick coating includes placing the ceramic coating in a coating bucket, adding the montmorillonite additive, and then rolling the coating bucket for 0.5 to 2 hours to prepare the ceramic non-stick coating.The following describes a method for preparing non-stick cookware using the ceramic non-stick coating of the present application with reference to the accompanying drawings. Figure 2 is a schematic diagram of a non-stick coating prepared using a polymethylsiloxane ceramic coating. Figure 3 is a schematic diagram of a non-stick coating prepared using the ceramic non-stick coating of the present application. Figure 4 is a schematic diagram of the surface of a non-stick coating formed by spraying the ceramic non-stick coating once. Figure 5 is a schematic diagram of the surface of a non-stick coating formed by spraying the ceramic non-stick coating twice according to an embodiment of the present disclosure. In an embodiment of the present application, the method for preparing non-stick cookware using the ceramic non-stick coating of the present application may include: spraying the ceramic non-stick coating onto the surface of a cookware substrate to form a non-stick coating precursor on the cookware substrate; and sintering the cookware to produce a non-stick cookware having a non-stick coating on the cookware substrate. In an embodiment of the present application, the step of spraying a ceramic non-stick coating may include: spraying a first portion of the ceramic non-stick coating onto the cookware substrate to form a bottom layer; and spraying the remaining portion of the ceramic non-stick coating onto the bottom layer to form a top layer, wherein the first portion of the ceramic non-stick coating used to form the bottom layer accounts for 30-40 wt% (preferably, 1 / 3 (33.3 wt%)) of the total weight of the ceramic non-stick coating. The spraying process may be air spraying, thermal spraying, or the like, and the present invention is not limited to such a spraying process. By spraying the ceramic non-stick coating twice, more montmorillonite and / or modified montmorillonite can be formed on the surface of the coating, thereby improving the non-stick properties of the coating. However, the first portion of the ceramic non-stick coating used to form the bottom layer cannot exceed 40 wt% of the total weight of the ceramic non-stick coating, otherwise the wear resistance of the coating will be reduced. Specifically, referring to FIG4 , the non-stick coating formed by spraying the ceramic non-stick coating once onto the cookware surface clearly has relatively little montmorillonite on the surface. However, referring to Figure 5, the non-stick coating formed by spraying the ceramic non-stick coating onto the cookware surface twice clearly has a relatively high concentration of montmorillonite on the surface. As shown in Figure 5, the montmorillonite in the first sprayed coating creates protrusions and depressions on the surface. The montmorillonite in the second sprayed coating fills the depressions in the first coating, forming a denser arrangement with the protruding montmorillonite particles in the first coating. The greater the amount of montmorillonite on the surface of the non-stick coating, the better the non-stick properties of the coating.The two-step spraying method described above can produce a non-stick coating precursor comprising montmorillonite and / or modified montmorillonite. However, to strengthen the bond between the non-stick coating formed from the non-stick coating precursor and the substrate, the substrate can be sandblasted before spraying the ceramic non-stick coating to increase the substrate's roughness. For example, the surface roughness of the substrate can be reduced to Ra3-Ra6 by sandblasting. Furthermore, to optimize the subsequent spraying process, the substrate can be preheated to 50-60°C before spraying (or, more specifically, after sandblasting) before spraying (or, after sandblasting). After the non-stick coating precursor is formed through the spraying process, it can be sintered. In embodiments of the present application, the sintering process can include a surface drying process and a main sintering process. The surface drying process can include preheating the cookware substrate, on which the non-stick coating precursor is formed, at a temperature of 80-120°C for 3-5 minutes. The surface drying step not only cures the surface, preventing dust from falling into the pot and affecting the coating's appearance, but also preheats the coating to prevent cracking and other problems caused by the rapid temperature rise during sintering. After the surface drying process, the main sintering process can be carried out. Here, the main sintering process includes placing the product in an oven or tunnel furnace and maintaining it at 280°C ± 20°C for 5 to 10 minutes. After the main sintering process, the cookware of the present invention is obtained, which has a non-stick coating including a montmorillonite additive formed on a substrate. In the embodiments of the present application, the above-mentioned method for preparing non-stick cookware using the ceramic non-stick coating of the present application can produce a relatively high amount of montmorillonite on the surface of the non-stick coating and effectively form raised structures on the substrate surface, thereby enhancing the non-stick properties of the non-stick coating. For example, referring to FIG2 , in a non-stick coating prepared using an existing ceramic coating, the lotus leaf-like external group -CH3 forms "hair" on the coating surface, which imparts non-stick properties. Referring to FIG3 , in a non-stick coating prepared using the ceramic non-stick coating of the present application, the lotus leaf-like external group (CH3) and the montmorillonite additive together form "hair" on the coating surface.As can be seen from Figures 2 and 3, the "hair" structure of the non-stick coating of the present application is significantly larger in size than that of prior art non-stick coatings (equivalent to larger surface protrusions on the coating), resulting in a rougher surface than prior art non-stick coatings, thereby improving the non-stick properties of the coating. In the present embodiment, the height of the "hair" structure (the surface protrusions of the coating, i.e., the lotus leaf-like external groups -CH3 and the montmorillonite additive together form the surface protrusions) is less than half the particle size of the montmorillonite additive powder. When the height of the surface protrusions exceeds half the particle size of the montmorillonite additive powder, the surface protrusions account for an excessive proportion of the total montmorillonite additive powder height, making them easily "pulled off" during use, reducing the service life. The height of the surface protrusions is related to the particle size of the montmorillonite additive powder: larger montmorillonite additive powder particles increase the height of the surface protrusions. In an embodiment of the present application, the montmorillonite additive has a particle size of 6.5 μm to 25 μm. Within this particle size range, the height of the resulting surface protrusions can be less than half the particle size of the montmorillonite additive powder. Furthermore, when heated, the internal pores of the montmorillonite in the non-stick coating increase, thereby absorbing more grease from the cooking process, ensuring that the coating surface retains more grease during use, thus providing excellent non-stick properties. Furthermore, as shown in FIG3 , the montmorillonite surface has a micro-protrusion structure. This micro-protrusion structure is an inherent property of montmorillonite. The spaces between the micro-protrusions on the montmorillonite surface can store oil. When heated, the montmorillonite expands in volume, increasing the distance between the micro-protrusions on the montmorillonite surface. This increases the oil storage capacity and enhances the non-stick properties of the non-stick coating. At room temperature, the distance between the micro-protrusions of montmorillonite is 15 nm to 100 nm.

[0003] 1.1 Effect of Montmorillonite Particle Size and / or Thermal Expansion Ratio on the Non-Stick Properties of Non-Stick Coatings. Example 1 Montmorillonite with a particle size of 6.5 μm was added to a polymethylsiloxane ceramic coating to prepare a ceramic non-stick coating. The thermal expansion ratio of the montmorillonite was 2, and the weight content of the montmorillonite was 10 wt% based on the total weight of the ceramic non-stick coating. oThe cookware substrate was sandblasted to a surface roughness of Ra 5. The cookware substrate was preheated to 55°C. The first portion of the ceramic non-stick coating was sprayed to form a bottom layer, followed by the remaining portion of the ceramic non-stick coating to form a top layer. The first portion of the ceramic non-stick coating accounted for 33.3 wt% of the total weight of the ceramic non-stick coating. The substrate sprayed with the ceramic non-stick coating was tack-dried at 100°C for 5 minutes. The substrate was then sintered at 280°C for 10 minutes to produce a non-stick cookware with a non-stick coating. Testing revealed that the height of the surface protrusions on the non-stick coating was 3 gm. o Example 2 differs from Example 1 in that the montmorillonite particle size is 8 gm and the thermal expansion ratio of montmorillonite is 1.8. Testing shows that the height of the surface protrusions on the non-stick coating is 3.5 μm. Example 3 differs from Example 1 in that the montmorillonite particle size is 12 gm and the thermal expansion ratio of montmorillonite is 1.5. Testing shows that the height of the surface protrusions on the non-stick coating is 5 gm. o The difference between Example 4 and Example 1 is that the particle size of montmorillonite is 16 gm and the thermal expansion ratio of montmorillonite is 1.2. After testing, the height of the surface protrusion of the non-stick coating is 6 gm. o The difference between Example 5 and Example 1 is that the particle size of montmorillonite is 20 gm and the thermal expansion ratio of montmorillonite is 0.9. After testing, the height of the surface protrusion of the non-stick coating is 8 gm. o The difference between Example 6 and Example 1 is that the particle size of montmorillonite is 25 gm and the thermal expansion ratio of montmorillonite is 0.5. After testing, the height of the surface protrusion of the non-stick coating is 12 gm. o Comparative Example 1 differs from Example 1 in that the montmorillonite particle size is 5.5 μm and the thermal expansion ratio of montmorillonite is 2.5. Testing shows that the height of the surface protrusions on the non-stick coating is 2 μm. Comparative Example 2 differs from Example 1 in that the montmorillonite particle size is 40 μm and the thermal expansion ratio of montmorillonite is 0.3. Testing shows that the height of the surface protrusions on the non-stick coating is 18 μm. o

[0004] 1.2 Effect of Modified Montmorillonite on the Non-Stick Properties of Non-Stick Coatings. Example 7 differs from Example 1 in that the montmorillonite is methyl silicone oil-modified montmorillonite, wherein the weight of the methyl silicone oil in the methyl silicone oil-modified montmorillonite is 1 times the weight of the montmorillonite. Example 8 differs from Example 7 in that the weight of the methyl silicone oil is 5 times the weight of the montmorillonite. Comparative Example 3 differs from Example 7 in that the weight of the methyl silicone oil is 6 times the weight of the montmorillonite.

[0005] 1.3 Effect of the Weight Content of Montmorillonite / Modified Montmorillonite on the Non-stick Properties of Non-stick Coatings Example 9 is different from Example 1 in that the weight content of montmorillonite is 5 wt% based on the total weight of the ceramic non-stick coating. o Example 10 is different from Example 1 in that the weight content of montmorillonite is 20 wt% based on the total weight of the ceramic non-stick coating. o Example 11 is different from Example 7 in that the weight content of the modified montmorillonite is 5 wt% based on the total weight of the ceramic non-stick coating. o Example 12 is different from Example 7 in that the weight content of the modified montmorillonite is 20 wt% based on the total weight of the ceramic non-stick coating. o Comparative Example 4 is different from Example 1 in that the weight content of montmorillonite is 3 wt% based on the total weight of the ceramic non-stick coating. o Comparative Example 5 is different from Example 1 in that the weight content of montmorillonite is 25 wt% based on the total weight of the ceramic non-stick coating. o

[0006] 1.4 Effect of the Number of Sprays of Ceramic Non-stick Coating and the Amount of Sprayed Each Time on the Non-stick Properties of the Non-stick Coating. Example 13 differs from Example 1 in that the first portion of the ceramic non-stick coating accounts for 30% of the total weight of the ceramic non-stick coating. Example 14 differs from Example 1 in that the first portion of the ceramic non-stick coating accounts for 40% of the total weight of the ceramic non-stick coating. Comparative Example 6 differs from Example 1 in that the ceramic non-stick coating is sprayed onto the substrate surface once. Comparative Example 7 differs from Example 1 in that the first portion of the ceramic non-stick coating accounts for 20 wt% of the total weight of the ceramic non-stick coating. oComparative Example 8 is different from Example 1 in that the first part of the ceramic non-stick coating accounts for 50 wt% of the total weight of the ceramic non-stick coating. o After testing, the initial non-stick properties, non-stick durability and hardness of the non-stick coating prepared above are shown in Table 1 below. The test method is:

[0007] (1) Initial non-stick test method: GB / T32095.2-2015 Fried egg non-stick test method, this method is an initial non-stick test, divided into I, II, and III levels, with I level having the best non-stickiness and III level having the worst non-stickiness;

[0008] (2) Non-stick durability test method: The non-stick durability test method in GB / T32388-2015 is measured in times. The higher the number, the longer the life. The non-stick result is evaluated every 1000 times, and the number of times when it reaches level III is recorded.

[0009] (3) Wear resistance: GB / T32388-2015 durable non-stick test method, after 1000 wears, clean and dry, record the mass loss before and after 1000 wears. The greater the mass, the worse the wear resistance. The mass loss should be less than 1.5g. When N1.5g, hard food on the surface film layer is very easy to scratch, and the service life is short. Table 1

[0010] Referring to Table 1, combined with Examples 1-6 and Comparative Examples 1 and 2, it can be seen that when the montmorillonite particle size is less than 6.5 μm, the resulting non-stick coating has poor wear resistance (mass loss of 1.5 μm). When the montmorillonite particle size is greater than 25 μm, the resulting non-stick coating has poor initial non-stick performance and poor non-stick durability. Combined with Examples 7 and 8 and Comparative Example 3, it can be seen that when the montmorillonite is modified with methyl silicone oil, the resulting non-stick coating has significantly improved non-stick durability. When the weight of the methyl silicone oil exceeds 5 times the weight of the montmorillonite, the methyl silicone oil exceeds the maximum adsorption capacity of the montmorillonite, resulting in a severely greasy surface and no improvement in long-term non-stick properties. Combined with Examples 9-12 and Comparative Examples 4 and 5, it can be seen that when the montmorillonite addition amount is less than 5 wt%, the resulting non-stick coating has poor non-stick properties. When the amount of montmorillonite added exceeds 20 wt%, the resulting non-stick coating exhibits poor wear resistance due to the high montmorillonite content. As shown in Examples 13-14 and Comparative Examples 6, 7, and 8, when the ceramic non-stick coating is sprayed onto a substrate surface once, the resulting non-stick coating has a low montmorillonite content, resulting in poor non-stick properties. When the first portion of the ceramic non-stick coating accounts for 20 wt% of the total weight of the ceramic non-stick coating, the resulting non-stick coating has a low montmorillonite content, resulting in poor non-stick properties. When the first portion of the ceramic non-stick coating accounts for 50 wt% of the total weight of the ceramic non-stick coating, the resulting non-stick coating has a high montmorillonite content, resulting in poor wear resistance. While the invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the claims and their equivalents. The embodiments should be considered in a descriptive sense only and not for the purpose of limitation. Therefore, the scope of the present invention is limited not by the specific embodiments of the present invention but by the claims, and all differences within the scope will be interpreted as included in the present invention.

Claims

Claims 1. A ceramic non-stick coating, characterized in that: The ceramic non-stick coating comprises a ceramic coating and a montmorillonite additive dispersed in the ceramic coating, wherein the montmorillonite additive comprises at least one of montmorillonite and modified montmorillonite, wherein the weight of the montmorillonite additive is 5wt% to 20wt% based on the total weight of the ceramic non-stick coating, wherein the montmorillonite has a particle size of 6.5 μm to 25 μm, and wherein the modified montmorillonite has a structure in which silicone oil is combined with montmorillonite.

2. The ceramic non-stick coating according to claim 1, characterized in that: The montmorillonite has a thermal expansion ratio of 0.5-2.

3. The ceramic non-stick coating according to claim 1 or 2, characterized in that: In the modified montmorillonite, the weight of the silicone oil is less than or equal to 5 times the weight of the montmorillonite.

4. A method for preparing the ceramic non-stick coating according to any one of claims 1 to 3, characterized in that the method comprises: providing a ceramic coating and a montmorillonite additive respectively; mixing and rolling the ceramic coating and the montmorillonite additive to obtain the ceramic non-stick coating.

5. The method according to claim 4, characterized in that: The step of providing a montmorillonite additive includes: providing montmorillonite; and immersing at least a portion of the montmorillonite in a silicone oil solution so that the silicone oil is combined with the montmorillonite to obtain a modified montmorillonite.

6. The method according to claim 5, characterized in that: The concentration of silicone oil in the silicone oil solution is not higher than 60wt% o 7. The method according to claim 5 or 6, characterized in that: The step of preparing the modified montmorillonite further comprises subjecting the montmorillonite combined with the silicone oil to ultrasonic treatment.

8. A ceramic coating, characterized in that: The ceramic coating is formed by using the ceramic non-stick coating according to any one of claims 1 to 3, wherein the ceramic coating has surface protrusions, and the height of the surface protrusions is less than 1 / 2 of the particle size of the montmorillonite additive.

9. A non-stick cookware, characterized in that: The non-stick cookware comprises a base and a The ceramic coating according to claim 8.

10. A method for preparing non-stick cookware using the ceramic non-stick coating according to any one of claims 1 to 3, characterized in that: The method comprises: spraying the ceramic non-stick coating on the surface of a substrate; performing surface drying on the substrate sprayed with the ceramic non-stick coating; and sintering the substrate sprayed with the ceramic non-stick coating to prepare a non-stick cookware.

11. The method according to claim 10, characterized in that: The step of spraying the ceramic non-stick coating comprises: spraying a first portion of the ceramic non-stick coating to form a bottom layer; and spraying the remaining portion of the ceramic non-stick coating to form a top layer, wherein the first portion of the ceramic non-stick coating accounts for % of the total weight of the ceramic non-stick coating. 30wt%-40wt% o 12. The method according to claim 10 or 11, characterized in that: The surface drying step includes preheating at a temperature of 80-120°C for 3 to 5 minutes.

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