Coating material, coating, preparation method of coating and cooking utensil

Abstract

The invention discloses a coating material, a coating, a preparation method of the coating and a cooking utensil, and belongs to the field of kitchen ware. The coating material is prepared from the following components in percentage by mass: 20%-40% of polyethersulfone resin, 5%-15% of montmorillonite / silicon dioxide particles, 15%-30% of silicone oil, 1%-8% of an auxiliary agent and 30%-50% of deionized water. According to the coating material provided by the invention, montmorillonite / silicon dioxide particles are introduced into a polyethersulfone system to construct a coating microstructure, and meanwhile, the wear resistance, non-viscosity and fluoride-free safety of a non-stick coating are improved by utilizing the self-lubricating property and non-viscosity of silicone oil.

Description

Technical Field

[0001] This invention relates to the field of kitchenware, specifically to a coating material, a coating and its preparation method, and cooking utensils. Background Technology

[0002] Non-stick pans overcome all the shortcomings of traditional pans, allowing for easy frying and stir-frying without food sticking to the bottom. They minimize oil usage, are easy to clean, keep the kitchen clean with less oil fumes, and can also help reduce fat intake, aligning with modern consumers' pursuit of low-fat, low-calorie diets. Fluoropolymers (such as polytetrafluoroethylene, PTFE), as materials with the lowest surface energy, possess excellent resistance to chemical corrosion and aging, and have been widely used in the preparation of non-stick coatings.

[0003] However, fluoropolymers pose potential hazards to human health and the environment, and there is currently a lack of non-stick coating materials that combine wear resistance, non-stick properties, and safety. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention proposes a coating material, a coating and its preparation method and a cooking utensil, aiming to solve the problem of the current lack of a non-stick coating material that combines wear resistance, non-stickness and safety.

[0005] To achieve the above objectives, the present invention provides a coating material, which, by weight percentage, comprises:

[0006] 20%–40% polyethersulfone resin,

[0007] 5%–15% montmorillonite / silica particles,

[0008] 15%–30% silicone oil,

[0009] 1% to 8% of adjuvants,

[0010] 30% to 50% deionized water.

[0011] Optionally, the silica of the montmorillonite / silica particles is grafted onto the lamellar structure surface of the montmorillonite.

[0012] Optionally, the coating material comprises 3% to 5% pigments and fillers by weight percentage.

[0013] Optionally, the silicone oil includes amino silicone oil.

[0014] To achieve the above objectives, the present invention provides a coating comprising the coating material described above.

[0015] Optionally, the coating is a single coating of the cooking utensil, or the coating is one layer of the non-stick coating of the cooking utensil.

[0016] Optionally, the thickness of the coating is 20 μm to 40 μm.

[0017] To achieve the above objectives, the present invention proposes a method for preparing the above-mentioned coating, comprising the following steps:

[0018] The cookware substrate is sandblasted, degreased, and cleaned to obtain a pre-treated cookware substrate.

[0019] The coating material is obtained by mixing polyethersulfone resin, montmorillonite / silica particles, silicone oil, pigments, fillers, additives, and deionized water in a certain proportion and filtering.

[0020] The pre-treated cookware substrate is preheated, and the coating material is sprayed onto the surface of the cookware substrate under a preset pressure, and then sintered and cured to obtain the coating.

[0021] Optionally, in the step of "mixing polyethersulfone resin, montmorillonite / silica particles, silicone oil, pigments, fillers, additives, and deionized water in a certain proportion and filtering to obtain a coating material," the method for preparing the montmorillonite / silica particles includes:

[0022] Montmorillonite was dispersed in a mixed solution of ammonia and ethanol to obtain a montmorillonite dispersion.

[0023] The montmorillonite dispersion was added dropwise to a solution containing tetraethyl orthosilicate to undergo a hydrolysis reaction, yielding montmorillonite / silica particles.

[0024] Optionally, in the step of "adding the montmorillonite dispersion dropwise to a solution containing tetraethyl orthosilicate to undergo a hydrolysis reaction to obtain montmorillonite / silica particles", the hydrolysis reaction time is 6h to 8h.

[0025] Optionally, in the step of "mixing polyethersulfone resin, montmorillonite / silica particles, silicone oil, pigments, fillers, additives, and deionized water in proportion and filtering to obtain a coating material", the mixing includes dispersion using a high-speed disperser at a speed of 800 rpm to 1000 rpm for a duration of not less than 30 minutes.

[0026] And / or, the filtration includes filtration through a 200-400 mesh filter.

[0027] Optionally, in the step of "preheating the pretreated cookware substrate, spraying the coating material onto the surface of the cookware substrate under a preset pressure, sintering and curing to obtain the coating", the preset pressure is an air pressure of 1 kg / cm² to 4 kg / cm².

[0028] And / or, the sintering and curing temperature is 230℃~250℃, and the sintering and curing time is 1.2h~1.6h.

[0029] To achieve the above objectives, the present invention provides a cooking utensil comprising a pot base and a non-stick coating, wherein the non-stick coating comprises the coating described above, or comprises a coating prepared by the above preparation method.

[0030] The coating material of this invention utilizes the excellent heat resistance, chemical stability, oxidation resistance, radiation resistance, water vapor resistance, flame retardancy, and excellent adhesion to metals of polyethersulfone resin as the main component. By leveraging the strong interfacial interaction between montmorillonite and silica, a dense micro / nano structure is formed between the montmorillonite / silica particles, significantly improving the mechanical durability of the coating. Simultaneously, the silica material reduces the surface energy of the coating, imparting excellent hydrophobic properties and playing a crucial role in the coating's non-stick properties. Furthermore, the introduction of fluorine-free silicone oil increases material safety and further reduces the surface energy of the coating, thereby enhancing its non-stick performance. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the coating of a cooking utensil according to an embodiment of the present invention, where reference numeral 1 indicates the coating and reference numeral 2 indicates the utensil substrate. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0034] Unless otherwise specified, all technical and scientific terms used herein have their usual meaning in the field to which the claimed subject matter pertains, and all reagents used are of industrial or analytical purity.

[0035] Non-stick pans overcome all the shortcomings of traditional pans, allowing for easy frying and stir-frying without food sticking to the bottom. They minimize oil usage, are easy to clean, keep the kitchen clean with less oil fumes, and can also help reduce fat intake, aligning with modern consumers' pursuit of low-fat, low-calorie diets. Fluoropolymers (such as polytetrafluoroethylene, PTFE), as materials with the lowest surface energy, possess excellent resistance to chemical corrosion and aging, and have been widely used in the preparation of non-stick coatings.

[0036] However, fluoropolymers pose potential hazards to human health and the environment, and there is currently a lack of non-stick coating materials that combine wear resistance, non-stick properties, and safety.

[0037] To address the aforementioned problems, this invention proposes a coating material comprising: polyethersulfone resin, montmorillonite / silica particles, silicone oil, additives, and deionized water.

[0038] In this scheme, polyethersulfone resin is used as the main material for the coating, taking advantage of its excellent heat resistance, chemical stability, oxidation resistance, radiation resistance, water vapor resistance, flame retardancy, and excellent adhesion to metals. The strong interfacial interaction between montmorillonite and silica promotes the formation of a dense micro / nano structure of montmorillonite / silica particles, which significantly improves the mechanical durability of the coating. At the same time, silica can reduce the surface energy of the coating, giving it excellent hydrophobic properties and playing an important role in the non-stick properties of the coating surface.

[0039] In addition, silicone oil typically refers to linear polysiloxanes that remain liquid at room temperature. It has a very low vapor pressure, a high flash point and ignition point, and a low freezing point, allowing for long-term use within a temperature range of -50℃ to +180℃. Introducing fluorine-free silicone oil materials offers enhanced safety. Furthermore, utilizing its numerous -Si-O- groups further reduces the surface energy of polyethersulfone resin, thereby enhancing the coating's non-stick properties and self-lubricating properties, ultimately improving the coating's wear life.

[0040] Non-stick properties are achieved by creating a surface with low surface tension. When a pan is heated, cooking oil is added and heated to cross-link and solidify, forming an oil film similar to a coating. This oil film is not easily detached even with continued heating. When the oil is reheated, it enters a low surface tension state, thus exhibiting non-stick properties.

[0041] In some embodiments of this solution, additives are used to improve various properties of the coating and promote film formation. These additives include driers, toughening agents, emulsifiers, thickeners, defoamers, leveling agents, anti-skinning agents, matting agents, light stabilizers, mildew inhibitors, and antistatic agents. It is understood that as long as the additives do not contain fluorine and do not compromise the safety of the coating material, they can be added as needed according to the actual conditions of coating preparation.

[0042] Furthermore, the silica of the montmorillonite / silica particles is grafted onto the lamellar surface of the montmorillonite.

[0043] Montmorillonite is composed of nano-thick layers of negatively charged silicate sheets stacked together by electrostatic interactions. Its crystal structure consists of two layers of silicon-oxygen tetrahedra sandwiching a layer of aluminum-oxygen octahedra, exhibiting a one-dimensional layered nanostructure. Montmorillonite possesses a large aspect ratio and extremely high specific surface area, which can enhance the protective performance of coatings by increasing the diffusion length of the electrolyte, reducing micropores and vacancies, and in some cases, increasing the crosslinking density. These layered particles, dispersed within the coating, effectively increase diffusion pathways, making it difficult for water and corrosive ions to permeate the coating, thus enhancing its corrosion resistance. In-situ growth of nano-silica forms a porous micro / nano structure on the surface of montmorillonite.

[0044] Therefore, the numerous micro / nanopapillary structures on the coating surface, resembling a "coral" morphology, can improve the wear life of the prepared coating. Furthermore, the static contact angle increases with the mass ratio of silica to montmorillonite, while the roll-off angle decreases with the same mass ratio. In some embodiments of this solution, the micro / nano composite structure of the coating surface can be directly observed using a scanning electron microscope.

[0045] Further, by weight percentage, the coating material comprises: 20% to 40% polyethersulfone resin, 5% to 15% montmorillonite / silica particles, 15% to 30% silicone oil, 1% to 8% additives, and 30% to 50% deionized water.

[0046] In this scheme, when the components of the coating material are within the above-mentioned range, the doping of montmorillonite / silica particles and silicone oil to polyethersulfone resin can be more rationally distributed, achieving better compatibility and making it less likely to cause local accumulation of montmorillonite / silica particles, which is beneficial to improving the overall stability of coating performance.

[0047] In some embodiments, the coating material comprises polyethersulfone resin in any value from 20% to 40%, such as 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36%, 38%, 40%, etc. In some embodiments, the coating material comprises montmorillonite / silica particles in any value from 5% to 15%, such as 5%, 7%, 9%, 11%, 13%, 15%, etc.

[0048] In some embodiments, the coating material includes silicone oil in any value from 15% to 30%, such as 15%, 18%, 21%, 24%, 27%, 30%.

[0049] In some embodiments, additives are added as needed in the range of 1% to 8%, based on the overall microstructure and performance of the non-destructive coating material and the safety of the coating.

[0050] In some embodiments, deionized water improves the fluidity of the material, making the coating material easier to apply to the surface of cooking utensils through processes such as spraying.

[0051] Furthermore, the coating material comprises 3% to 5% pigments and fillers by weight percentage. The addition of pigments and fillers allows the coating color to be adjusted to coordinate with the appearance of the cooking utensils, achieving an aesthetically pleasing effect.

[0052] In some embodiments, the coating material includes pigments and fillers of any value from 3% to 5%, such as 3%, 3.5%, 4%, 4.5%, 5%.

[0053] Furthermore, the silicone oil includes one of amino silicone oil, dimethyl silicone oil, hydroxyl silicone oil, and hydrogen-containing silicone oil.

[0054] Preferably, the silicone oil is an amino silicone oil, which refers to the addition of amino groups to the side chains or chain ends of the organosiloxane polymer, which react with the functional groups of the polyethersulfone resin. This is more conducive to introducing siloxane into the polyethersulfone resin, thereby reducing the internal stress of the coating, improving the low-temperature impact strength, reducing the surface energy, thereby enhancing the non-stick properties and self-lubricating properties of the coating, and thus improving the wear life of the coating.

[0055] To address the aforementioned problems, this invention proposes a coating comprising the aforementioned coating material. The coating in this solution, based on the aforementioned coating material, possesses excellent wear resistance and non-stick properties, making it suitable for application in cooking appliances such as electric pressure cookers, grills, automatic stir-fry machines, air fryers, or electric griddles.

[0056] Furthermore, the coating is a single coating of the cooking utensil, or the coating is one layer of a non-stick coating of the cooking utensil.

[0057] In some embodiments, the coating of this solution is directly applied to the surface of the cookware substrate. Due to the adhesive properties of polyethersulfone resin, good adhesion between the coating and the cookware substrate can be achieved. In other embodiments, at least one adhesive layer and / or roughening layer is also provided between the cookware substrate and the coating of this solution to enhance the adhesion between the cookware substrate and the non-stick coating.

[0058] Furthermore, the coating thickness is 20μm to 40μm. In this embodiment, a coating thickness less than 20μm will reduce the coating's lifespan and increase the risk of breakage and blistering; a coating thickness greater than 40μm will affect the heat transfer performance of the cooking utensils. In some embodiments, the coating thickness is any value within the range of 20μm to 40μm, such as 20μm, 22μm, 24μm, 26μm, 28μm, 30μm, 32μm, 34μm, 36μm, 38μm, and 40μm.

[0059] To address the above problems, this invention proposes a method for preparing the aforementioned coating, comprising the following steps:

[0060] S1: Sandblast, degrease, and clean the cookware substrate to obtain a pre-treated cookware substrate;

[0061] In some embodiments, sandblasting increases the roughness of the cookware substrate, increases the contact area between the cookware substrate and the coating, and enhances the adhesion of the coating.

[0062] S2: Mix polyethersulfone resin, montmorillonite / silica particles, silicone oil, pigments, fillers, additives, and deionized water in a certain proportion and filter to obtain the coating material;

[0063] Mixing includes processes such as crushing, stirring, dispersing, emulsifying, and dissolving. During these processes, mechanochemical reactions occur between the raw materials, generating coating materials. In some embodiments, mixing can be achieved using equipment capable of the above objectives, such as high-speed dispersers, high-shear dispersers, and high-speed dispersion homogenizers.

[0064] S3: Preheat the pretreated cookware substrate, spray the coating material onto the surface of the cookware substrate under a preset pressure, and sinter and cure to obtain the coating.

[0065] The coating material in this solution is blown into a mist by airflow and adheres to the surface of the object. The working method of the coating being pressed or sucked out of the container by external force and forming a mist that adheres to the surface of the object is called spraying. Spraying can make the coating more uniform. It is more efficient than manual brushing when applied to uneven surfaces, and the coating film is smooth and beautiful.

[0066] Further, in step S2, the method for preparing the montmorillonite / silica particles includes:

[0067] Montmorillonite was dispersed in a mixed solution of ammonia and ethanol to obtain a montmorillonite dispersion.

[0068] The montmorillonite dispersion was added dropwise to a solution containing tetraethyl orthosilicate, resulting in a hydrolysis reaction to yield montmorillonite / silica particles. After the tetraethyl orthosilicate hydrolyzes into sol particles, these particles initially aggregate near the montmorillonite sheets and undergo a condensation reaction. Some of the sol particles also undergo condensation reactions with the hydroxyl groups on the montmorillonite surface. As the reaction proceeds, an ordered silica sol layer forms around the montmorillonite sheets. During the condensation process, the sol particles connect the different montmorillonite sheets, forming a dense coating. In the sol polymerization process, montmorillonite guides the orderly polymerization of the sol particles, increasing the density of the coating and reducing defects that occur during curing.

[0069] Furthermore, in the step of "adding the montmorillonite dispersion dropwise to a solution containing tetraethyl orthosilicate to undergo a hydrolysis reaction to obtain montmorillonite / silica particles", the hydrolysis reaction time is 6h to 8h.

[0070] In some embodiments, the hydrolysis reaction time is any value from 6h to 8h, such as 6h, 6.5h, 7h, 7.5h, 8h, etc.

[0071] Further, in step S2, the mixing includes dispersion using a high-speed disperser at a speed of 800 rpm to 1000 rpm for a duration of not less than 30 minutes;

[0072] And / or, the filtration includes filtration through a 200-400 mesh filter.

[0073] High-speed dispersers use the high-speed rotation of the dispersion disc teeth to agitate and mix materials, subjecting them to high-speed and intense shearing, impact, crushing, and dispersion, thereby achieving rapid mixing, dissolving, dispersing, and refining.

[0074] In some embodiments, the dispersion speed is any integer value from 800 rpm to 1000 rpm, such as 800 rpm, 820 rpm, 840 rpm, 860 rpm, 880 rpm, 900 rpm, 920 rpm, 940 rpm, 960 rpm, 980 rpm, 1000 rpm, etc.

[0075] In some embodiments, filtration includes filtering through a filter screen of any mesh size from 200 to 400 mesh, such as 200 mesh, 250 mesh, 300 mesh, 350 mesh, or 400 mesh. By filtering out montmorillonite / silica particles that do not meet the particle size requirements or have agglomerated, a more uniform coating material is obtained.

[0076] Furthermore, in step S3, the preset pressure is an air pressure of 1 kg / cm² to 4 kg / cm².

[0077] And / or, the sintering and curing temperature is 230℃~250℃, and the sintering and curing time is 1.2h~1.6h.

[0078] In some embodiments, sintering and curing can be performed in a curing sintering furnace, where the sol-gel-based coating is heat-treated to cause the network of the sol-gel-based matrix material to crosslink and transform the deposited material into a functionalized coating.

[0079] To achieve the above objectives, the present invention provides a cooking utensil, comprising a cookware substrate and a non-stick coating, wherein the non-stick coating comprises the coating described above, or comprises a coating prepared by the above-described preparation method. The cooking utensil includes, but is not limited to, electric pressure cookers, rice cookers, grills, automatic stir-fry machines, air fryers, or electric griddles.

[0080] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0081] Example 1:

[0082] The cookware substrate is sandblasted, degreased, and cleaned to obtain a pre-treated cookware substrate.

[0083] By mass percentage, 30% polyethersulfone resin, 10% montmorillonite / silica particles, 20% silicone oil, 3% pigments and fillers, 5% additives, 3% pigments and fillers, and 32% deionized water are dispersed in a high-speed disperser at 900 rpm, and then filtered through a 200-mesh sieve to obtain the coating material.

[0084] The pretreated cookware substrate is preheated, and the coating material is sprayed onto the surface of the cookware substrate under a pressure of 2 kg / cm². The coating is then sintered and cured at 240°C for 1.5 h to obtain the coating.

[0085] Example 2-11

[0086] The method for preparing the coating material is the same as that in Example 1, with the differences detailed in Table 1. Comparison of features between the examples and comparative examples.

[0087] Comparative Example 1:

[0088] The method for preparing the coating material is the same as in Example 1, except that: instead of adding montmorillonite / silica particles, 5% nano-montmorillonite and 5% nano-silica are added and dispersed together with the remaining raw materials in a high-speed disperser.

[0089] Furthermore, the microstructure and thickness of the coatings prepared in the examples and comparative examples were characterized, and the non-stickiness, adhesion, and abrasion resistance of the coatings were tested using the following methods:

[0090] (1) Conduct a non-stick test for fried eggs.

[0091] Referring to standard GB / T 32095.1~3-2015 "Performance and Test Specification of Non-stick Surface of Household Food Metal Cooking Utensils", the non-stick coating surface of the sample was lightly wiped with a soft cloth dampened with vegetable oil, washed with warm water above 60℃ and detergent, dried, and then subjected to a frying egg test to determine the quality of the non-stick pan's non-stick properties. After the frying egg non-stick test, the results were rated by checking the adhesion between the fried egg and the pan.

[0092] (2) Adhesion test

[0093] Adhesion is the general term for the bonding force between a coating and a substrate surface generated by physical and chemical interactions. The method for determination is the cross-cut test, in which a 5×5 grid of 1mm-spaced squares is cut using a knife. The grids are then graded according to the rating standards specified in GB / T 9286—1988, with grade 0 being the best and grade 5 being the worst.

[0094] (3) Abrasion resistance: The abrasion resistance of the coating was evaluated by measuring the abrasion rate of the silicone spatula after 1000 friction cycles at 200℃.

[0095] The test results are shown in Table 2 below.

[0096] Table 1. Coating Material Parameters

[0097]

[0098] Table 2. Performance Test Results

[0099] non-stick Adhesion Wear rate / % Example 1 Level 1 Level 0 10 Example 2 Level 1 Level 0 5 Example 3 Level 1 Level 2 20 Comparative Example 1 Level 3 Level 1 30

[0100] By comparing the performance data in Table 2, Example 2 showed the best performance in terms of non-stickiness, adhesion, and abrasion resistance. This is likely due to the higher polyethersulfone resin content in its coating material and the appropriate ratio of montmorillonite / silica particles. Although Examples 1 and 3 were slightly inferior to Example 2 in some properties, their overall performance was still good. Comparative Example 1 performed poorly in terms of non-stickiness and abrasion resistance, which may be due to the different way the nanomaterials were added to the coating material, affecting the overall performance of the coating.

[0101] The above data demonstrates that the coating material provided by this invention, under a defined ratio, utilizes the excellent heat resistance, chemical stability, oxidation resistance, radiation resistance, water vapor resistance, flame retardancy, and excellent adhesion to metals of polyethersulfone resin as the main component. By leveraging the strong interfacial interaction between montmorillonite and silica, the coating achieves a dense micro / nano structure, significantly improving its mechanical durability. Simultaneously, the silica material reduces the surface energy of the coating, imparting excellent hydrophobic properties and playing a crucial role in its non-stick properties. Furthermore, the introduction of fluorine-free silicone oil further reduces the surface energy of the coating, thereby enhancing its non-stick performance.

[0102] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A coating material, characterized in that, The coating material comprises, in percentage by mass: 20% to 40% of polyether sulfone resin, 5% to 15% of montmorillonite / silica particles, 15% to 30% of silicone oil, 1% to 8% of auxiliary agent, 30% to 50% of deionized water.

2. The coating material of claim 1, wherein, The silica of the montmorillonite / silica particles is grafted on the surface of the sheet structure of the montmorillonite.

3. The coating material of claim 1 or 2, wherein The coating material comprises 3% to 5% of color filler, in percentage by mass.

4. The coating material according to any one of claims 1 to 3, wherein The silicone oil comprises amino silicone oil.

5. A coating characterized in that, The coating material comprises the coating material according to any one of claims 1 to 4.

6. The coating of claim 5, wherein, The coating is a single coating of the cooking utensil, or the coating is one layer of the non-stick coating of the cooking utensil.

7. The coating according to claim 5 or 6, characterized in that The thickness of the coating is 20 μm to 40 μm.

8. A method for producing a coating as claimed in any one of claims 5 to 7, characterized in that The method comprises the following steps: sandblasting, degreasing and cleaning the base of the pot to obtain a pretreated base of the pot; mixing, in proportion, the polyether sulfone resin, the montmorillonite / silica particles, the silicone oil, the color filler, the auxiliary agent and the deionized water to obtain a coating material, and filtering the coating material; preheating the pretreated base of the pot, spraying the coating material on the surface of the base of the pot under a preset pressure, and sintering and curing to obtain a coating.

9. The method of claim 8, wherein the coating is prepared by In the step of mixing, in proportion, the polyether sulfone resin, the montmorillonite / silica particles, the silicone oil, the color filler, the auxiliary agent and the deionized water to obtain a coating material, the preparation method of the montmorillonite / silica particles comprises: dispersing the montmorillonite in a mixed solution of ammonia and ethanol to obtain a montmorillonite dispersion; dropping the montmorillonite dispersion into a solution comprising tetraethyl orthosilicate to generate a hydrolysis reaction, and obtaining the montmorillonite / silica particles.

10. The method of claim 9, wherein the coating is prepared by In the step of dropping the montmorillonite dispersion into a solution comprising tetraethyl orthosilicate to generate a hydrolysis reaction, and obtaining the montmorillonite / silica particles, the time of the hydrolysis reaction is 6 h to 8 h.

11. The method of claim 8, wherein the coating is prepared by In the step of mixing, in proportion, the polyether sulfone resin, the montmorillonite / silica particles, the silicone oil, the color filler, the auxiliary agent and the deionized water to obtain a coating material, the mixing comprises dispersing by using a high-speed disperser, the speed of the dispersing is 800 rpm to 1000 rpm, and the time of the dispersing is not less than 30 min; and / or, the filtering comprises filtering through a filter screen with a mesh size of 200 to 400.

12. The method of claim 8, wherein the coating is prepared by In the step of preheating the pretreated base of the pot, spraying the coating material on the surface of the base of the pot under a preset pressure, and sintering and curing to obtain a coating, the preset pressure is an air pressure of 1 kg / cm2 to 4 kg / cm2; and / or, the temperature of the sintering and curing is 230 ℃ to 250 ℃, and the time of the sintering and curing is 1.2 h to 1.6 h.

13. A cooking appliance characterized by, The cooking utensil comprises a base and a non-stick coating, the non-stick coating comprises the coating according to any one of claims 5 to 7, or the non-stick coating is prepared by the method according to any one of claims 8 to 12.

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