Sustained-release material and preparation method therefor, modified ceramic coating and preparation method therefor, non-stick coating, and cooking utensil

Abstract

The present invention relates to a sustained-release material and a preparation method therefor, a modified ceramic coating and a preparation method therefor, a non-stick coating, and a cooking utensil. The sustained-release material comprises microspheres having a pore structure and silicone oil filled in the pore structure of the microspheres, wherein the microspheres having a pore structure are formed by a mixed slurry comprising abrasion-resistant particles and a binder by means of spray drying, and the abrasion-resistant particles comprise at least one of ferroferric oxide particles, iron carbide particles, titanium carbide particles, chromium carbide particles, zirconium carbide particles, iron nitride particles, titanium nitride particles, aluminum nitride particles, chromium nitride particles and zirconium nitride particles. By means of the sustained-release material of the present application, the silicone oil in the cooking utensil coating formed by a ceramic coating having the sustained-release material can be slowly released, and the abrasion-resistant particles of the microspheres can effectively resist abrasion and high temperature during cooking, thereby avoiding the loss of silicone oil and ensuring long-lasting non-stickiness.

Description

[0001] The present invention belongs to the technical field of non-stick coating, and particularly relates to a slow-release material and a preparation method thereof, a modified ceramic coating and a preparation method thereof, a non-stick coating and a cooking utensil. In the field of cooking utensils, non-stick materials have always been a research hotspot, and a liquid non-stick coating as a type of non-stick material can be widely applied due to easy application and high coating uniformity. At present, the liquid non-stick coating mainly includes PTFE coating and ceramic coating, and the ceramic coating has been widely used as a material for forming a non-stick coating of a cooking utensil due to its unique performance, such as good initial non-stick performance and corrosion resistance. Taking a pot as an example, under the conditions of high-temperature cooking, especially Chinese cooking, and use of a metal spatula, the pot with a coating formed by the ceramic coating will be damaged by heat and abrasion, so that silicone in the coating is gradually lost and a methyl group is damaged, thereby leading to quick decrease of non-stick durability and poor long-term non-stick performance. Based on the above-mentioned problems of the prior art, the present invention provides a slow-release material and a preparation method thereof, a ceramic coating and a preparation method thereof, a non-stick coating and a cooking utensil, so as to solve the problem of poor long-term non-stick performance of a coating formed by a conventional ceramic coating. According to an aspect of an example embodiment, a slow-release material is provided, wherein the slow-release material includes microspheres with a pore structure and silicone filled in the pore structure of the microspheres, and the microspheres with the pore structure are formed by spray drying of a mixed slurry including wear-resistant particles and a binder, wherein the wear-resistant particles include a base material, and the base material includes at least one of a four-iron oxide particle, an iron carbide particle, a titanium carbide particle, a cobalt carbide particle, an iron nitride particle, a titanium nitride particle, an aluminum nitride particle, a cobalt nitride particle and a tungsten nitride particle. According to the slow-release material provided by the example embodiment of the present application, a cooking utensil coating formed by a ceramic coating with the slow-release material can gradually release silicone during use, and the material forming the microspheres with the pore structure has high hardness, high wear resistance and stability (thermal stability and stability of a particle accumulation structure), can effectively resist abrasion and high temperature during cooking, and avoids loss of silicone or a methyl group, so as to achieve long-term non-stick performance.In some embodiments, the wear-resistant particles further comprise an auxiliary material, which includes at least one of aluminum oxide particles, titanium oxide particles, copper oxide particles, molybdenum oxide particles, silicon dioxide particles, cerium oxide particles, and zirconium oxide particles. In these embodiments, the overall performance of the slow-release material can be improved by utilizing the above-mentioned properties of the auxiliary material. Specifically, aluminum oxide particles can be added to improve the hardness, wear resistance, and high-temperature stability of the slow-release material. Titanium oxide particles can be added to improve the overall wettability of the slow-release material. Copper oxide particles can be added to improve the color, hygroscopicity, and chemical stability of the slow-release material. Molybdenum oxide particles can be added to improve the high-temperature resistance and wear resistance of the slow-release material. Silicon dioxide particles can be added to strengthen the chemical stability and high-temperature resistance of the slow-release material. Cerium oxide particles can be added to improve the physical and chemical properties of the slow-release material. Zirconium oxide particles can be added to strengthen the hardness and chemical stability of the slow-release material. In some embodiments, the weight of the main material accounts for 50%-98% of the total weight of the microspheres, with the remainder being the auxiliary material, based on the total weight of the microspheres. In these embodiments, the various components in the microspheres are within a predetermined range, and the properties of the microspheres in terms of cost, hardness, and wear resistance, etc. can be balanced according to actual requirements. In some embodiments, the particle size of the wear-resistant particles is 100 nanometers to 3 microns, which is more conducive to the formation of the above-mentioned microspheres with the desired pore structure, and the porosity of the pore structure of the formed microspheres can be controlled to easily meet the requirements of the locking silicone oil. The particle size of the slow-release material is 10 microns to 25 microns, which is easy to disperse in the ceramic coating precursor and can ensure the overall performance of the modified ceramic coating formed. In some embodiments, the porosity of the pore structure is 30%-60%, and the size of a single pore is 30 nanometers to 1 micron. The microspheres with such a pore structure can accommodate the size of the silicone oil molecules of the present application, making it easy for them to enter, thereby ensuring that the content of the silicone oil in the slow-release material formed meets the predetermined requirements.Meanwhile, the material forming the microspheres with the pore structure has low heat conduction performance, which can effectively reduce the heat conduction and diffusion, so as to reduce the possibility of the direct contact of the silicone oil with high temperature, thereby being able to improve the stability and safety of the slow-release material. In some embodiments, the contact parts of the wear-resistant particles in contact with each other are embedded with each other, so that the microspheres have a strong enough binding force between the particles, so as to ensure the stability of the microspheres in the ceramic coating precursor, and avoid the collapse of the microspheres in the modified ceramic coating or in the process of forming the non-stick coating, so as to cause the silicone oil to be released too early. In some embodiments, the microspheres also have the carbonization product of the binder, which is attached to part of the surface of the wear-resistant particles, and the weight ratio of the carbonization product of the binder to the wear-resistant particles in the microspheres is (0.5-1):98o In these embodiments, the microspheres also have a small amount of the carbonization product of the binder, and since the carbonization product of the binder is mainly composed of non-polar carbon elements and has a certain lipophilicity, it can further improve the lipophilicity of the whole non-stick material, so that the microspheres are more easily filled and locked with the silicone oil. In some embodiments, the silicone oil includes 20%-30% of low-molecular-weight silicone oil, 40%-60% of medium-molecular-weight silicone oil, and 20%-30% of high-molecular-weight silicone oil in terms of weight percentage, wherein the molecular weight of the low-molecular-weight silicone oil is between 500-1000, the molecular weight of the medium-molecular-weight silicone oil is between 3000-6000, and the molecular weight of the high-molecular-weight silicone oil is between 12000-30000. In these embodiments, the silicone oil with large molecular weight is more firmly combined with the pore structure formed by the accumulation of the wear-resistant particles, and has a slower release speed, the small-molecular-weight silicone oil has better free mobility, thereby having better non-stickiness, and the medium-molecular-weight silicone oil takes into account the free mobility and firmness of the combination. Therefore, by combining the low-molecular-weight silicone oil, the medium-molecular-weight silicone oil, and the high-molecular-weight silicone oil, on the one hand, the possibility of the silicone oil entering the microspheres is further increased, and on the other hand, in the case that the content of the medium-molecular-weight silicone oil is more than 50%, the silicone oils with different binding forces in the mixed form can be continuously released at each stage of use, so as to have better non-stick effect. As an example, the binding force between the silicone oil and the microspheres is generally between 5MPa-10MPa. oThe adhesion force thus formed can ensure the continuous release of the silicone oil, and prevent the silicone oil from being released too early or not being released at all. According to a second aspect of the present application, a method for preparing a sustained-release material is provided, which includes: forming microspheres having a porous structure by spray drying a mixed slurry including wear-resistant particles and a binder, and then sintering at a preset temperature; filling silicone oil into the porous structure of the microspheres, thereby obtaining a sustained-release material including silicone oil filled in the porous structure of the microspheres, wherein the wear-resistant particles include a base material, and the base material includes at least one of a ferrite particle, a carbide particle of iron, a carbide particle of titanium, a carbide particle of cobalt, a carbide particle of nickel, a nitride particle of iron, a nitride particle of titanium, a nitride particle of aluminum, a nitride particle of cobalt, and a nitride particle of nickel. In some embodiments, before the step of filling the silicone oil, the microspheres are pretreated to change the charge state of the surface, and then the step of filling the silicone oil is performed. In these embodiments, the interaction force between the pretreated microsphere surface and the silicone oil is enhanced, so that the silicone oil is more easily adsorbed to the microsphere surface and penetrates into the porous structure, significantly improving the filling rate of the silicone oil. The charge distribution of the pretreated microsphere surface is more uniform, which helps the silicone oil to form a uniform oil film layer on the microsphere surface and further penetrate into the porous structure, and can ensure the uniform distribution of the silicone oil in the microspheres, improving the uniformity of the sustained-release effect. By optimizing the filling effect and distribution state of the silicone oil in the microspheres, the sustained-release effect and stability of the sustained-release material can be improved, so that the sustained-release material can continuously release the silicone oil for a longer period of time, meeting the application requirements. In some embodiments, the preset temperature is 500°C-650°C, and the sintering at the preset temperature includes heating the spray-dried microspheres to the preset temperature at a heating rate of 15°C / min-20°C / min, and the holding time is 6h-8h, during which the binder in the spray-dried microspheres can be carbonized as much as possible. Then, the temperature is increased to 1200°C-1250°C at a heating rate of 55°C / min-100°C / min, and the holding time is 12h-24h, so that the metal oxide particles in contact with each other are embedded in the contact part after sintering to form the microspheres.In this process, the binder gradually volatilizes in the process of sintering, and the volume of the wear-resistant particles shrinks under the influence of high temperature of 1200°C-1250°C in the subsequent process, leaving pores between the particles or inside the particles, and finally forming microspheres with a certain pore structure. According to the third aspect of the present application, a modified ceramic coating is provided, wherein the modified ceramic coating comprises a ceramic coating precursor and the slow-release material as described above dispersed in the ceramic coating precursor. In some embodiments, the weight ratio of the slow-release material and the ceramic coating precursor is (5-30):(61-92), and the slow-release material and the ceramic coating precursor have a suitable weight ratio, so that the film-forming property, stability, and non-stickiness of the obtained modified ceramic coating can be balanced, thereby ensuring the non-stickiness, wear resistance, and bonding strength of the formed non-stick coating. The particle size of the slow-release material is 10-25 microns; and / or the slow-release material has a spherical or spheroidal structure. The slow-release material with a suitable particle size and shape is easy to disperse in the ceramic coating precursor, and can ensure the overall performance of the formed modified ceramic coating. According to the fourth aspect of the present application, a method for preparing a modified ceramic coating is provided, wherein the method comprises providing a ceramic coating precursor, providing the slow-release material as described above, and mixing the ceramic coating precursor and the slow-release material to obtain the modified ceramic coating. In some embodiments, the step of providing the ceramic coating precursor comprises providing a first coating comprising a siloxane monomer, providing a second coating comprising a silicic acid solution, and providing a third coating comprising an organic acid substance; mixing the second coating and the third coating to form a first mixture, so that the pH of the first mixture is adjusted to be between 2 and 4; and mixing the first coating and the first mixture to form the ceramic coating precursor. In these embodiments, the ceramic coating precursor formed by the siloxane polymer can further improve the non-stickiness of the ceramic coating, and better adapt to the demand of cookware for non-stickiness. According to the fifth aspect of the present application, a non-stick coating is provided, wherein the non-stick coating is formed by the modified ceramic coating as described above.In some embodiments, the non-stick coating comprises at least two sub-layers; wherein the content of the release particles in each sub-layer is increased in a direction from inside to outside; or the molecular weight of the silicone oil in each sub-layer is different and the molecular weight of the silicone oil is increased. In these embodiments, in a direction from inside to outside, i.e. from the inner surface of the cookware body to the outside, by making the content of the release material present in a gradient, the coating can maintain the non-stick ability for a longer period of time. As the outer layer of release material is consumed, the release material in the inner layer will gradually supplement to the outer layer, ensuring that the non-stick coating has long-lasting non-stick performance. At the same time, the bottom layer is in direct contact with the cookware body, so it has excellent adhesion and durability. In order to ensure the close combination between the coating and the cookware body, the silicone oil content of the bottom layer is relatively low, which can reduce the risk of delamination between the bottom layer and the cookware body due to too good non-stickness of the bottom layer. In a direction from inside to outside, the molecular weight of the silicone oil in each sub-layer is increased in turn, because the larger the molecular weight, the higher the degree of combination in the release material, in this way, the release time of the silicone oil in the non-stick coating can be longer, and the long-lasting non-stickness is improved. According to the sixth aspect of the present application, a cookware is provided, wherein the cookware comprises a cookware body and a non-stick coating formed on the inner surface of the cookware body, wherein the non-stick coating is the non-stick coating described above. In some embodiments, a cover layer is further provided outside the non-stick coating to cover the surface and surface pores of the non-stick coating, wherein the cover layer is formed of silicone oil, grease or other ceramic coating different from the components of the modified ceramic coating. On the one hand, the cover layer can further improve the non-stick effect, on the other hand, the cover layer can prevent food residues or grease from penetrating into the interior of the coating, affecting the non-stickness and service life of the non-stick coating. In some embodiments, the inner surface of the cookware body is a rough surface or a rough transition layer is provided between the cookware body and the non-stick coating to improve the bonding force between the coating and the cookware body.FIG. 1 shows a SEM image of the shape of microspheres of the slow-release material after sintering according to an exemplary embodiment of the present application; FIG. 2 shows a SEM image of the shape of microspheres of the slow-release material before sintering according to an exemplary embodiment of the present application; FIG. 3 shows a structural diagram of the slow-release material according to an exemplary embodiment of the present application; FIG. 4 shows a structural diagram of the modified ceramic coating according to an exemplary embodiment of the present application; FIGS. 5 to 8 respectively show structural diagrams of a non-stick coating according to exemplary embodiments of the present application. Specific embodiments will now be described in greater detail below with reference to the accompanying drawings, in which embodiments are shown. However, the present application can be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art. Like reference numerals refer to like elements throughout. A conventional ceramic coating mainly relies on the silicon methyl groups and doped silicone oil in the ceramic coating to achieve a non-stick effect. Under the conditions of this special cooking (high-temperature stir-frying and metal spatula), the loss of silicone oil in the coating formed by the ceramic coating is accelerated, the silicon methyl groups are destroyed, resulting in the non-stick effect of the cookware with the coating being lost after a period of use, and finally the phenomenon of cooking sticking to the pot occurs. If the ceramic coating can continuously store oil, an effective oil film can be formed to isolate the food and the coating surface, thereby achieving the purpose of long-lasting non-stick. Therefore, the present application provides a slow-release material for a ceramic coating, the slow-release material being in a granular form, including microspheres having a pore structure and silicone oil filled in the pore structure of the microspheres, the microspheres having the pore structure being formed by spray drying of a mixed slurry including wear-resistant particles and a binder, wherein the wear-resistant particles include a lipophilic base material, the base material including at least one of Fe3O4 particles, a carbide of iron particle, a carbide of titanium particle, a carbide of tungsten particle, a carbide of chromium particle, a nitride of iron particle, a nitride of titanium particle, a nitride of aluminum particle, a nitride of chromium particle, and a nitride of tungsten particle. In a preferred embodiment, the wear-resistant particles are Fe3O4 particles, because Fe3O4 not only has good lipophilicity, but also has good wear resistance.In the present application, the wear-resistant particles themselves do not have pores, and the mixed slurry including the wear-resistant particles is formed into microspheres with a pore structure by a spray drying method, wherein the pore structure is formed after the spray drying of the mixed slurry, and can provide storage space for silicone oil. The wear-resistant particles include the above-mentioned oleophilic main material particles, and based on the principle of "like dissolves like", the oleophilic material helps the effective adsorption and stable storage of silicone oil in the microspheres, and can ensure that the silicone oil can be released smoothly from the microspheres during cooking. Therefore, in the process of forming the slow-release material, other methods such as vacuum / pressure infiltration do not need to be excessively used, and the slow-release material with a predetermined silicone oil filling rate can be obtained while ensuring the integrity of the slow-release material. In addition, the material forming the microspheres with a pore structure has high hardness, high wear resistance, and stability (thermal stability and stability of the particle accumulation structure), which can effectively resist wear during cooking, thereby protecting the cookware coating from being damaged, avoiding methyl loss, and the material forming the microspheres with a pore structure has low thermal conductivity, which can effectively reduce the conduction and diffusion of heat, reduce the adverse effects (such as thermal decomposition) of high temperature on silicone oil, and avoid the loss of silicone oil due to high temperature. In this way, the cookware coating formed by the ceramic coating with the slow-release material can gradually release silicone oil during use, and can effectively resist wear and high temperature during cooking due to the presence of microspheres, can achieve the purpose of lasting non-stick, and can prolong the service life of the coating. It should be noted that the present application concept does not limit the slow-release material to be used only in ceramic coatings, and based on the prior art, the slow-release material can be used in other non-stick coatings or non-stick materials to enable the slow release of silicone oil therein to achieve the effect of lasting non-stick. As an example, the slow-release material can be used as a core, and a metal material can be used as a shell (outer layer) to form a new non-stick material with a core-shell structure. FIG. 1 shows a morphology SEM image of the microspheres of the slow-release material after sintering according to the exemplary embodiments of the present application. FIG. 2 shows a morphology SEM image of the microspheres of the slow-release material before sintering according to the exemplary embodiments of the present application.Referring to FIG. 1 and FIG. 2, it can be seen that the spray-dried microspheres do not have obvious pores before sintering, and after sintering at the temperature of the present application, the microspheres have obvious pore structures, and the pores in the pore structure are basically uniformly distributed. FIG. 3 shows a structural diagram of a slow-release material according to an exemplary embodiment of the present application. As shown in FIG. 3, the slow-release material 10 includes microspheres 11 having pore structures formed by wear-resistant particles through spray drying, and silicone oil 12o filled in the pore structure of the microspheres 11. It should be noted that in FIG. 3, the color is set to gray only for the purpose of clearly showing the position of the silicone oil, and does not mean that the silicone oil of the present application has a gray color. In some embodiments, in addition to including particles of an oleophilic base material, the wear-resistant particles also include auxiliary materials, wherein the auxiliary materials include at least one of aluminum oxide particles, titanium oxide particles, copper oxide particles, molybdenum oxide particles, silicon dioxide particles, cerium oxide particles, and zirconium oxide particles. In these embodiments, the overall performance of the slow-release material can be improved by utilizing the properties of the above-mentioned auxiliary materials. Specifically, aluminum oxide particles can be added to improve the hardness, wear resistance, and high-temperature stability of the slow-release material. Titanium oxide particles can be added to improve the overall wetting performance of the slow-release material. Copper oxide particles can be added to improve the color, hygroscopicity, and chemical stability of the slow-release material. Molybdenum oxide particles can be added to improve the high-temperature resistance and wear resistance of the slow-release material. Silicon dioxide particles can be added to enhance the chemical stability and high-temperature resistance of the slow-release material. Cerium oxide particles can be added to improve the physical and chemical properties of the slow-release material. Zirconium oxide particles can be added to enhance the hardness and chemical stability of the slow-release material. In some embodiments, the weight of the base material accounts for 50%-98% of the total weight of the microspheres, and the balance is the auxiliary material, based on the total weight of the microspheres being 100%. In actual applications, the weight ratio of each component in the microspheres can be adjusted according to the specific use and performance requirements of the microspheres. For example, if it is necessary to improve the oleophilicity of the microspheres, the content of the base material can be set relatively high. In these embodiments, each component in the microspheres can be balanced within a predetermined range according to actual requirements to balance the properties of the microspheres in terms of cost, hardness, wear resistance, and the like.According to the present application, the microspheres have a special pore structure, according to electron microscope images, the pore size of the pore structure is slightly smaller than the size of the wear-resistant particles, in some embodiments, the pore rate of the pore structure of the microspheres is 30%-60%, and the size of a single pore is 30 nanometers-1 micrometer. The microspheres with such a pore structure can adapt to the size of the silicone oil molecules of the present application, making it easy to enter, so as to ensure that the content of silicone oil in the formed release material can meet the predetermined requirements. At the same time, the microspheres with such a pore structure can effectively reduce the heat conduction and dispersion, so as to reduce the possibility of direct contact of silicone oil with high temperature, thereby being able to improve the stability and safety of the release material. According to the present application, the particle size of the microspheres is in the range of 10 micrometers-25 micrometers, and correspondingly, the particle size of the release material in the form of particles formed after the microspheres are filled with silicone oil is also in the range of 10 micrometers-25 micrometers, which is easy to disperse in the ceramic coating precursor, and can ensure the overall performance of the modified ceramic coating. This is because the silicone oil is mainly adsorbed or wrapped inside the microspheres, so that no obvious external coating layer is formed or the microspheres are significantly expanded. As an example, the silicone oil can be fixed in the interior of the microspheres by adsorption, penetration or chemical reaction and the like. It should be noted that a small part of the silicone oil can be fixed on the surface of the release material according to the present application. According to the present application, the silicone oil is in a liquid state, and the release material filled with the liquid silicone oil is added to the conventional ceramic coating, so as to form a modified ceramic coating with good non-stick ability, and the cookware formed by the modified ceramic coating can gradually release the silicone oil on the surface of the coating during use and form an oil film in the use process to further reduce the friction and adhesion between the coating and the contact object, thereby improving the non-stick ability and durability of the coating. In some embodiments, the silicone oil is adsorbed or bonded in the pore structure of the microspheres, and can provide non-stick ability for the ceramic coating. Here, the silicone oil can be selected from at least one of methyl silicone oil, dimethyl silicone oil, hydroxyl silicone oil, hydrogen-containing silicone oil and polyaldehyde modified silicone oil. In specific applications, various silicone oil forms can be matched with the properties of the microspheres formed by the corresponding wear-resistant particles, and the present application does not make too many limitations.In some embodiments, the contact portions of the wear-resistant particles in contact with each other interlock, so that the microspheres have a strong enough binding force between the particles to ensure the stability of the microspheres in the ceramic coating precursor, avoiding the collapse of the microspheres in the modified ceramic coating or during the process of forming a non-stick coating, causing the silicone oil to be released too early. In some embodiments, the microspheres also include a carbonized product of a binder attached to part of the surface of the wear-resistant particles, and the weight ratio of the carbonized product of the binder to the wear-resistant particles in the microspheres is (0.5-1):98o In these embodiments, the microspheres also include a small amount of carbonized product of the binder, which is mainly composed of non-polar carbon elements and has a certain lipophilicity, thus further improving the lipophilicity of the non-stick material as a whole, making it easier for the microspheres to fill and lock the silicone oil. In some embodiments, the silicone oil includes 20%-30% low molecular weight silicone oil, 40%-60% medium molecular weight silicone oil, and 20%-30% high molecular weight silicone oil, by weight percentage, wherein the molecular weight of the low molecular weight silicone oil is between 500-1000, the molecular weight of the medium molecular weight silicone oil is between 3000-6000, and the molecular weight of the high molecular weight silicone oil is between 12000-30000. In these embodiments, the macromolecular weight silicone oil is more firmly combined with the pore structure formed by the accumulation of wear-resistant particles, and the release speed is slower, the small molecular weight silicone oil has better free mobility, thus having better non-stick properties, and the medium molecular weight silicone oil takes into account the free mobility and firmness of the combination. Therefore, by combining low molecular weight silicone oil, medium molecular weight silicone oil and high molecular weight silicone oil, on the one hand, the possibility of silicone oil entering the microspheres is further increased, and on the other hand, when the content of medium molecular weight silicone oil is more than 50%, in the mixed form of silicone oil, silicone oil with different binding forces can be continuously released at each stage of use, to better non-stick effect. As an example, the binding force between the silicone oil and the microspheres is generally 5-10 MPa. oThe combination of the two can ensure the continuous release of the silicone oil, and avoid the premature release or non-release of the silicone oil. Next, the method for preparing the slow-release material according to the present application will be described in detail. According to the second aspect of the present application, a method for preparing a slow-release material is provided, wherein the method comprises: Step S1, forming microspheres with a pore structure by spray drying a mixed slurry comprising wear-resistant particles and a binder, and then sintering at a preset temperature; and Step S2, filling the silicone oil into the pore structure of the microspheres to obtain the slow-release material comprising the silicone oil filled in the pore structure of the microspheres. According to the method for preparing the slow-release material provided in the embodiments of the present application, the wear-resistant particles themselves do not have pores, and the mixed slurry comprising the wear-resistant particles is used to form the microspheres with the pore structure by spray drying, wherein the pore structure is formed after the spray drying of the mixed slurry, and can provide storage space for the silicone oil. The wear-resistant particles comprise the above-mentioned particles of the oleophilic base material, and based on the principle of similar phase solubility, the oleophilic material helps the effective adsorption and stable storage of the silicone oil in the microspheres, and can ensure that the silicone oil can be released from the microspheres smoothly during cooking. Therefore, in the process of forming the slow-release material, other methods such as vacuum / pressure infiltration do not need to be excessively used, and the slow-release material with a predetermined silicone oil filling rate can be obtained under the premise of ensuring the integrity of the slow-release material. In addition, the material for forming the microspheres with the pore structure has high hardness, high wear resistance, and stability (thermal stability and stability of the particle pile structure), and is non-toxic and harmless, which meets the food safety standards. As the attachment structure of the silicone oil, the material can effectively resist wear and tear during the cooking process, thereby protecting the cookware coating from being easily damaged, avoiding methyl loss, and the material for forming the microspheres with the pore structure has low thermal conductivity, which can effectively reduce the conduction and diffusion of heat, reduce the adverse effects of high temperature on the silicone oil (for example, thermal decomposition), and avoid the loss of the silicone oil due to high temperature. In this way, the cookware coating formed with the slow-release material can gradually release the silicone oil during use, and can effectively resist wear and tear and high temperature during the cooking process due to the presence of the microspheres, so as to achieve the purpose of long-lasting non-stick and prolong the service life of the coating. Next, the method for preparing the slow-release material according to the present application will be described in detail.Providing wear-resistant particles According to the present application, the wear-resistant particles provided in the above exemplary embodiments can form microspheres with the desired pore structure through spray drying (powder granulation), can ensure that the silicone oil molecules are easy to enter, and can effectively protect the silicone oil molecules located relatively internally from being directly contacted with the heat source to volatilize, in addition, the microspheres can effectively reduce the conduction and diffusion of heat, reduce the possibility of direct contact of the silicone oil with high temperature, thereby improving the stability and safety of the sustained-release material. In some embodiments, the particle size of the wear-resistant particles is 100 nanometers to 3 microns. When the wear-resistant particles are in the range of 100 nanometers to 3 microns, it is easier to form the above-mentioned microspheres with the desired pore structure, and the porosity of the pore structure of the formed microspheres can be easily controlled to meet the needs of locking silicone oil. The particle size of the above-mentioned material can be the maximum length of each particle, without specifically limiting that the material has a spherical or spherical-like shape. For example, but not limited to, when the material has an elliptical shape, the particle size of the material can refer to the length of the major axis. According to the present application, by selecting the particles and the particle accumulation mode, microspheres with high oil storage capacity are obtained. In some embodiments, the wear-resistant particles are oleophilic base materials, preferably Fe3O4 particles, the wear-resistant particles are spherical or spherical-like, and the pore-structured microspheres formed therefrom have a relatively uniform pore distribution and a high through-hole porosity, which not only facilitates the adsorption and storage of silicone oil, but also ensures the mechanical strength and wear resistance of the formed microspheres. Forming a mixed slurry According to the present application, the step of forming a mixed slurry includes providing wear-resistant particles, a binder, and ball-mixing the wear-resistant particles and the binder to form a mixed slurry. The wear-resistant particles only include a base material, or a base material and an auxiliary material. The weight ratio of the base material and the auxiliary material is (50-98):(0-48), for example, the mixed slurry includes 50%-98% of the base material, 1%-2% of the binder, and 0%-58% of the auxiliary material, based on the total weight of the mixed slurry being 100%. Specifically, the wear-resistant particles and the binder are added to a ball mill tank, and deionized water is added as a grinding medium, and grinding is performed for 4h-8h, thereby obtaining a uniformly dispersed mixed slurry including wear-resistant particles and a binder.The binder in the mixed slurry can enhance the binding force between the particles forming the microspheres to form a stable particle stack, so that the microspheres have a certain mechanical strength, and the microspheres are prevented from collapsing to cause the silicone oil to be released too early in the modified ceramic coating or in the process of forming a non-stick coating. As an example, the binder includes an alcohol-based binder and a cellulose-based binder, and as an example, the binder can include at least one of a cellulose-based binder and an alcohol-based binder. The cellulose-based binder can include at least one of a methylol cellulose-based binder, a hydroxyethyl cellulose-based binder, and a hydroxypropyl cellulose-based binder. The alcohol-based binder can include at least one of a polyvinyl alcohol-based binder, a polypropylene glycol-based binder, and other higher alcohol-based binders containing six or more carbon atoms. However, the present application is not limited thereto, and an appropriate binder can be selected according to actual needs. It should be noted that the alcohol-based binder is completely volatilized, and the cellulose-based binder is partially formed into a carbonized product of the binder. Since the carbonized product of the binder is mainly composed of non-polar carbon elements, it has a certain lipophilicity, and can facilitate the filling of silicone molecules into the microspheres. In the embodiment, the mixed slurry includes the wear-resistant particles and the binder, and the weight ratio of the wear-resistant particles to the binder is 98:(1-2). As an example, the binder includes an alcohol-based binder and a cellulose-based binder, and as an example, the binder can include at least one of a cellulose-based binder and an alcohol-based binder. The cellulose-based binder can include at least one of a methylol cellulose-based binder, a hydroxyethyl cellulose-based binder, and a hydroxypropyl cellulose-based binder. The alcohol-based binder can include at least one of a polyvinyl alcohol-based binder, a polypropylene glycol-based binder, and other higher alcohol-based binders containing six or more carbon atoms. However, the present application is not limited thereto, and an appropriate binder can be selected according to actual needs. It should be noted that the binder according to the present application is volatilized or carbonized in the subsequent sintering process. Here, carbonization is a process in which, under high temperature, hydrogen, oxygen, and the like other than carbon are removed as low molecular compounds through thermal decomposition, and only the residual carbon is obtained. Volatilization is a process in which an organic substance is converted from a liquid state to a gaseous state after reaching the boiling point.According to the present application, under inert atmosphere such as nitrogen, oxygen, etc., with fast heating rate, high sintering temperature and long sintering time, a small portion of the binder will evaporate, leaving pores, and most of the binder will carbonize, forming a high-carbon-content material, the carbonized product of the binder, and the adjacent particles will interact with each other to form a microsphere with a stack of oxide particles and carbonized product and a porous structure. As an example, the carbonization temperature of the binder of the present application is generally between 250°C and 500°C, under the influence of subsequent sintering temperature and time, most of the binder will form a carbonized product. In some embodiments, 10% of the binder will evaporate, and 90% of the binder will carbonize. And since the carbonized product of the binder is mainly composed of non-polar carbon elements, it has a certain lipophilicity, and such microspheres are easier to be filled with silicone oil to form a slow-release material. Spray drying to form microspheres After the slurry is prepared, the mixed slurry is spray dried. According to some embodiments of the present application, the mixed slurry is atomized into fine droplets using a spray drying device (such as a pressure spray dryer, a centrifugal spray dryer, etc.). The atomized droplets are in contact with hot air, and the solvent evaporates rapidly, and the structure of the porous microspheres is formed between the wear-resistant particles and the binder. As an example, the mixed slurry can be fed onto a high-speed spinning atomization disc to form droplets, and then the droplets are blown into a drying tower using hot air, the droplets are temporarily stopped during the descending process, and finally the wet microspheres are formed. According to the present application, by adjusting the process parameters of spray drying (for example, the rotation speed of the atomization disc and the temperature of the hot air), the particle size, pore size and distribution, etc. of the porous microspheres can be controlled. As an example, by controlling the rotation speed of the atomization disc, the mixed slurry can be dispersed into extremely small droplets during the high-speed movement of the atomization disc. In some embodiments, the rotation speed of the atomization disc can be controlled in the range of 4000 revolutions / minute-15000 revolutions / minute, preferably in the range of 6000 revolutions / minute-12000 revolutions / minute. According to some embodiments of the present application, the temperature of the hot air can be controlled in the range of 60°C-100°C, the temperature of the drying tower can be controlled in the range of 100°C-400°C, and the short residence time of the droplets in the drying tower can be controlled in the range of 5 seconds-15 seconds.The hot air with relatively low temperature can reduce the loss of the binder, so that enough binder is reserved in the obtained pre-formed wet microspheres, and the binder is lost in the subsequent sintering process to form corresponding pores, thereby increasing the amount of air holes in the microspheres with pore structure. Sintering the microspheres after spray drying according to the method for manufacturing microspheres of the present application, the wet microspheres obtained after spray drying are sintered. In the sintering process, the abrasion-resistant particles in contact with each other are embedded in each other at the contact part after sintering to form the microspheres, so that the particles in the microspheres have a strong enough binding force to ensure the stability of the microspheres in the subsequent process. According to some embodiments of the present application, the microspheres after spray drying can be heated to a temperature above the carbonization temperature at a high heating rate in an inert atmosphere such as nitrogen, oxygen, etc., and kept for a long time, so that as much binder as possible is carbonized in this process. As an example, the microspheres are placed in a sintering furnace in an inert atmosphere such as nitrogen, oxygen, etc., the initial temperature for sintering is 20°C-30°C, the heating rate is 15°C / min-20°C / min, the high heating rate can avoid the volatilization of the binder, the temperature is raised to 500°C-650°C at a heating rate of 15°C / min-20°C / min, then, the temperature is kept for 6h-8h, in this process, the binder in the microspheres after spray drying can be carbonized as much as possible. Finally, the temperature is raised to 1200°C-1250°C at a heating rate of 55°C / min-100°C / min, and kept for 12h-24h, in this process, the particles of adjacent metal oxides can interact with each other to embed each other at the contact part, shrink in volume, and leave pores between the particles, and finally form the microspheres with a certain pore structure and carbonized product of the abrasion-resistant particles and the binder. As an example, in the microspheres, the weight ratio of the carbonized product of the binder and the abrasion-resistant particles is (0.5-1):98o, so the metal oxide coating formed thereby has abrasion-resistant particles and carbonized product of the binder, and the carbonized product of the binder is attached to part of the surface of the abrasion-resistant particles.Continuing with the above examples, in the metal oxide coating, the weight ratio of the carbonized product of the binder and the wear-resistant particles is (0.5-1):98. In these embodiments, the microspheres also have a small amount of the carbonized product of the binder, and since the carbonized product of the binder is mainly composed of non-polar carbon elements, it has a certain lipophilicity, thus further improving the lipophilicity of the microspheres as a whole, making it easy to fill silicone oil to form a slow-release material. In addition, in the process of sintering, when the wear-resistant particles include titanium oxide, the titanium oxide will at least partially form titanium suboxide under the influence of a reducing atmosphere and high temperature in the solid-phase sintering, and the special chemical properties and surface structure of the titanium suboxide help to reduce the contact between food and the surface of the cookware and the possibility of food sticking. According to the method for preparing a slow-release material according to the present application, the sintered microspheres can be screened after the sintering step, so as to obtain microspheres in different particle size intervals. The microspheres in different particle size intervals can be screened according to needs, so as to be applied to different products. For example, the sintered powder is screened by a vibrating screen to obtain spherical or spherical-like microspheres with a particle size of 10-25 microns. According to the method for preparing a slow-release material according to the present application, the finally formed microspheres are not a single particle in the sense of quantity, but can be a plurality of particles aggregated together. The particle size of the finally formed microspheres is not less than the particle size of the original various powders. According to the present application, the internal or inter-particle channels of the microspheres after spray drying can allow gas or liquid to pass through, that is, the pore structure of the microspheres formed by spray drying according to the present application is mainly open pores or connected pores, that is, through holes, and a small number of closed pores. As an example, the volume fraction of the through holes is about 80%-90%, and the balance is closed pores. In some embodiments, the microspheres have a special pore structure, and in some embodiments, the porosity of the pore structure of the microspheres is 30%-60%, and the size of a single pore is 30-1 microns. The microspheres with such a pore structure can adapt to the size of the silicone oil molecules according to the present application, making it easy to enter, so as to ensure that the content of silicone oil in the formed slow-release material meets the predetermined requirements. At the same time, the microspheres with such a pore structure can effectively reduce the conduction and diffusion of heat, reduce the possibility of direct contact of silicone oil with high temperature, and thus improve the stability and safety of the slow-release material.According to the present application, the particle size of the microspheres is in the range of 10-25 microns, and the microspheres have a pore structure formed by the mutual accumulation of the particles, which provides accommodation space for the silicone oil. Accordingly, the particle size of the sustained-release material formed after the microspheres are filled with silicone oil is also in the range of 10-25 microns. This is because the silicone oil is mainly filled in the interior of the microspheres, thus no obvious external coating layer is formed or the microspheres are not significantly expanded. As an example, the silicone oil can be fixed in the interior of the microspheres by adsorption, penetration or chemical reaction, etc. It needs to be noted that the surface of the sustained-release material according to the present application can fix a part of the silicone oil by adsorption, penetration or chemical reaction, etc. It is well known that the molecular structure of the silicone oil contains a large number of silicon-oxygen bonds, and these bonds have high bond energy, which makes the silicone oil have low surface tension, thus showing good lubricity and low surface energy characteristics. Whether the silicone oil can enter the pore structure depends not only on the compatibility of the silicone oil molecules and the microspheres, such as size compatibility, affinity, etc., but also on the influence of various factors such as the viscosity and surface tension of the silicone oil. If the pore size of the pore structure is small, and the viscosity of the silicone oil is large or the surface tension is high, then the silicone oil can be difficult to enter the pore structure. Conversely, if the pore size of the pore structure is large, and the viscosity of the silicone oil is small or the surface tension is low, then the silicone oil is more likely to enter the pore structure. Considering the difficulty of the silicone oil to penetrate into the pore structure, the inventors found that not only can the silicone oil be selected, but also the oleophilic microspheres can be subjected to a predetermined pretreatment to further ensure the effective filling of the silicone oil and to ensure the filling rate of the silicone oil in the sustained-release material. In some embodiments, the microspheres can be pretreated before the step of filling the silicone oil to change the surface charge state, and then the step of filling the silicone oil is performed. The surface charge state of the microspheres will directly affect the interaction between the microspheres and the silicone oil. If the microspheres have a surface charge, the silicone oil molecules will be attracted to the surface of the microspheres due to electrostatic effects, thus helping the silicone oil to be better filled into the pore structure of the microspheres. By changing the surface charge state of the microspheres through pretreatment, the interaction between the silicone oil and the microspheres can be optimized, and the filling rate can be improved. In these embodiments, the interaction between the pretreated microspheres surface and the silicone oil is enhanced, making it easier for the silicone oil to be adsorbed to the surface of the microspheres and penetrate into the pore structure, thus significantly improving the filling rate of the silicone oil.The surface charge distribution of the pretreated microspheres is more uniform, which helps the silicone oil form a uniform covering layer on the surface of the microspheres and further penetrate into the pore structure, so as to ensure the uniform distribution of the silicone oil in the microspheres and improve the uniformity of the sustained-release effect. By optimizing the filling effect and distribution state of the silicone oil in the microspheres, the sustained-release effect and stability of the sustained-release material can be improved, so that the sustained-release material can continuously release silicone oil for a longer time to meet the application requirements. According to the present application, the microspheres can be pretreated by chemical modification or plasma treatment technology. In some embodiments, the microspheres are pretreated, including modifying the surface of the microspheres by using a chemical reagent to introduce specific functional groups, so as to change the charge properties of the surface. For example, a group with positive charge or negative charge is introduced on the surface of the microspheres through a chemical reaction. As an example, the chemical reagent can be a silane coupling agent, and the silane coupling agent (such as KH-570) reacts with the functional groups such as hydroxyl groups on the surface of the microspheres to form a silicon-carbon bond, so as to graft the silane coupling agent to the surface of the microspheres. In this step, the mass concentration of the silane coupling agent is 0.1%-3%, and the reaction can be promoted by conditions such as heating and stirring. As an example, the stirring time is 0.5h-2h, and then the modification is performed at 65 °C-75 °C T for 5h-8h. In other embodiments, the surface of the microspheres can be treated by using plasma technology, which can change the chemical structure and charge distribution of the surface, so that the effective regulation of the charge state of the surface of the microspheres can be achieved without introducing additional chemical reagents. The silicone oil is selected from at least one of methyl silicone oil, dimethyl silicone oil, hydroxyl silicone oil, hydrogen-containing silicone oil and polyurethane modified silicone oil according to the present application. The above silicone oils have specific viscosity and surface tension, which are easier to enter the pore structure of the microspheres. In addition, the silicone oil includes 20%-30% of low molecular weight silicone oil, 40%-60% of medium molecular weight silicone oil, and 20%-30% of high molecular weight silicone oil by weight percentage, wherein the molecular weight of the low molecular weight silicone oil is between 500-1000, the molecular weight of the medium molecular weight silicone oil is between 3000-6000, and the molecular weight of the high molecular weight silicone oil is between 12000-30000.According to the present application, after the selection of the silicone oil and the microspheres, the silicone oil is used to impregnate the non-preprocessed microspheres or the silicone oil is injected into the non-preprocessed microspheres, so as to obtain the slow-release material in which the silicone oil is combined in the pore structure of the microspheres. As an example, in the slow-release material, the weight of the silicone oil accounts for 40%-60% of the total weight of the slow-release material, and the balance is the microspheres formed by the wear-resistant particles. The silicone oil is used to impregnate the preprocessed microspheres or the silicone oil is injected into the preprocessed microspheres, so as to obtain the slow-release material in which the silicone oil is combined in the pore structure of the microspheres at a higher content. As an example, in the slow-release material, the weight of the silicone oil accounts for 50%-65% of the total weight of the slow-release material. The addition amount of the silicone oil in the conventional ceramic material has an upper limit. If the addition amount of the silicone oil is increased blindly, the silicone oil may be precipitated, aggregated or volatilized in the coating, thereby affecting the overall performance of the ceramic coating, for example, the stability. In view of this, the inventors find that the silicone oil can be formed into a slow-release material, and then the slow-release material is dispersed in the conventional ceramic coating. In this way, on the one hand, the content of the silicone oil in the conventional ceramic coating can be relatively increased, and on the other hand, the overall performance of the ceramic coating will not be affected. In addition, the silicone oil in the conventional ceramic coating can be replaced by the silicone oil slow-release material, and the silicone oil in the silicone oil slow-release material can be filled, so that the coating formed by the modified ceramic coating can be slowly released during use and as much as possible not be directly affected by heat. According to a third aspect of the present application, a modified ceramic coating is provided. FIG. 4 shows a structural diagram of the modified ceramic coating provided according to an exemplary embodiment of the present application. As shown in FIG. 4, the modified ceramic coating according to the exemplary embodiment can include a ceramic coating precursor 20 and a slow-release material 10 uniformly dispersed in the ceramic coating precursor 20. The ceramic coating precursor 20 can correspond to the matured ceramic coating used in the art, and thus can have the components of the ceramic coating commonly used in the art, so that the method for preparing the ceramic coating known in the art can be used.However, the exemplary embodiments are not limited thereto, as mentioned above in the method of preparing a ceramic coating precursor according to the inventive concept described in connection with the exemplary embodiments, the ceramic coating precursor can be prepared by the method described below, and the ceramic coating precursor prepared by using the method of the inventive concept described below can have a more excellent characteristic of providing tack-free property in combination with the release material. In some embodiments, the weight ratio of the release material and the ceramic coating precursor is (5-30) : (61-92), the release material and the ceramic coating precursor have a suitable weight ratio, the film-forming property, stability, and tack-free property of the modified ceramic coating obtained can be balanced, thereby being able to secure the tack-free property, abrasion resistance, and adhesion of the tack-free coating layer formed. In some embodiments, the particle size of the release material is 10-25 micrometers; and / or the release material has a spherical or spheroid structure, the release material having the particle size and shape is easily dispersed in the ceramic coating precursor, and the overall properties of the modified ceramic coating formed can be secured. Above, the ceramic coating according to the inventive concept is described in detail in connection with the exemplary embodiments, and hereinafter, the method of preparing the ceramic coating will be described in detail. The steps of the method of preparing the ceramic coating according to the inventive concept can include the steps of preparing the ceramic coating precursor and the release material, respectively, and mixing the ceramic coating precursor with the release material to obtain the modified ceramic coating. However, the exemplary embodiments are not limited thereto, that is, the step of preparing the ceramic coating precursor can be combined with the step of preparing the release material. Hereinafter, the two methods of preparing the modified ceramic coating according to the present application will be described in detail. According to the fourth aspect of the present application, a method of preparing a modified ceramic coating is provided, wherein the method includes: Step S21 of providing a ceramic coating precursor. Step S22 of providing a release material. Step S23 of mixing the ceramic coating precursor with the release material to obtain a modified ceramic coating. Hereinafter, the method of preparing the modified ceramic coating according to the present application will be described in detail. The preparation of the ceramic coating precursor according to the present application, Step S21 of providing the ceramic coating precursor includes: Step S211 of providing a first coating including a siloxane monomer. Step S212 of providing a second coating including a silica sol.Step S213, a third coating material including an organic acid substance is provided. Step S214, the second coating material and the third coating material are mixed to form a first mixed material, so that the pH of the first mixed material is adjusted to be between 2 and 4. Step S215, the first coating material and the first mixed material are mixed to form a ceramic coating precursor. According to the present application, the first coating material includes a siloxane monomer, the second coating material includes a silica sol, and further includes a filler as an auxiliary component, and optionally a pigment, a wetting agent, a thickening agent, and an emulsifier as auxiliary components, and a solvent, the third coating material can include an organic acid substance, which is also referred to as an organic acidic substance, and refers to an organic compound capable of providing H+ions to a solution to lower the pH of the solution. As an example, the organic acid substance can be an organic acid, and in the third coating material, a pH buffer and a catalyst (acetic acid error) can also be included, but these components are optional components, and are not necessary components in the third coating material. In the first coating material, according to an exemplary embodiment, the siloxane monomer is used to form polysiloxane during the formation of the ceramic coating, and thus the siloxane monomer here can include a substance known in the art for use in the condensation to form polysiloxane. According to an exemplary embodiment, the siloxane monomer can include at least one of methyltrimethoxysilane, methyltriethoxysilane, and dimethyldimethoxysilane, but is not limited thereto. In addition, the first coating material can include tetraethyl orthosilicate for condensation to form polysiloxane in addition to the siloxane monomer, and in this case, in the first coating material, the siloxane monomer can account for 80-97% by weight of the first coating material, and the tetraethyl orthosilicate can account for 3-20% of the first coating material. The second coating material includes a silica sol, which is a main film-forming substance of the ceramic coating, and undergoes a sol-gel reaction with the polysiloxane under acidic conditions to form a ceramic coating precursor, and thus a commercially available general silica sol can be selected as the silica sol in the second coating material of the present inventive concept. The second coating material can also optionally include auxiliary components and a solvent, in which the auxiliary components can be a filler, an optional pigment, a wetting agent, a thickening agent, and an emulsifier, etc.The filler plays a role in increasing the wear resistance of the coating, and thus, the inventive concept is not limited to the type of filler, and a general filler can be used, for example, at least one of mica powder, kaolin, montmorillonite, silicon carbide, alumina, and silica can be used. The pigment is mainly used to impart different colors to the coating, and thus, a general inorganic pigment can be used, and the inorganic pigment is excellent in heat resistance and safety, and is suitable for use in a high-temperature field. According to an exemplary embodiment, at least one of carbon black, copper black, titanium white powder, and iron oxide can be used as the filler. In addition, in order to provide excellent properties of the second coating, at least one of a wetting agent, a thickening agent, and an emulsifier can be further included in the material. The solvent can include deionized water, and in order to secure a volatilization rate during drying of the coating, isopropyl alcohol can be further included. In addition, the ratio between isopropyl alcohol and water is not limited, and the ratio between isopropyl alcohol and water can be selected as needed. As an example, the second coating can include, in terms of weight percentage: 30 wt% to 48 wt% of silica sol, 8 wt% to 13 wt% of pigment, 8 wt% to 25 wt% of filler, 0.2 wt% to 1 wt% of wetting agent, 1 wt% to 3 wt% of thickening agent, 3 wt% to 5 wt% of emulsifier, and the balance of isopropyl alcohol and deionized water. However, the exemplary embodiment is not limited thereto, and one or more of unnecessary components can be omitted. The third coating includes an organic acid substance for adjusting the pH of the silica sol in a subsequent process, so that the silica sol can react with the first coating in an acidic environment, and thus, an organic acid commonly used for ceramic coating in the art can be used. According to an exemplary embodiment, at least one of formic acid and acetic acid can be selected as the organic acid, and when both formic acid and acetic acid are included, the weight ratio between formic acid and acetic acid can be between 4:6 and 1:1. In addition, in the third coating, a pH buffer and a catalyst can be optionally included as non-essential components. Here, the pH buffer and the catalyst can be a pH buffer and a catalyst known in the art used in a process of adjusting a strong acidic catalyst used for ceramic coating, for example, the pH buffer can be a weak acid such as boric acid, and the catalyst for accelerating the reaction speed of sol-gel can be acetic acid.However, the exemplary embodiments are not limited to the kinds of the pH buffer and the catalyst, and a suitable pH buffer and a catalyst can be omitted or appropriately selected based on the prior art. According to the exemplary embodiments, the third coating can include 80-97 parts by weight of a formic acid and acetic acid mixture, 1-2 parts by weight of a boric acid pH buffer, and 0.5 parts by weight of an acetic acid catalyst, based on 100 parts by weight. After the materials mentioned above are provided, a mixing step can be performed. In this context, the mixing step can include a first mixing step of mixing the second coating with the third coating to obtain the first material, and a second step of mixing the result of the first mixing step (i.e., the first material) with the first coating. Specifically, 40-60 parts by weight of the second coating can be mixed with 1-2 parts by weight of the third coating to adjust the pH of the mixture to less than or equal to 4 using the acidity of the third coating, to obtain the first material. Since the third coating includes a solid filler and an optional pigment, the third coating can be added to a mill and milled for 0.5 h-2 h before mixing or during preparation of the third coating, to sufficiently disperse and mill the third coating to a particle size of, for example, less than or equal to 15 micrometers, to obtain a uniformly dispersed slurry. After the second coating is mixed with the third coating, the mixture can be rolled and dispersed for a predetermined time (e.g., 0.5 h) to allow the first material to have a high dispersion degree. After the first material is obtained, the first coating can be added to the first material. Here, the parts by weight ratio of the amount of the first coating added to the second coating can be in the range of (20-30):(40-60). After the first coating is added, uniform shaking can be continued to allow the first coating and the second coating to undergo a sol-gel reaction in an acidic environment, to form a ceramic coating precursor. In these embodiments, the ceramic coating precursor including a methylsilsesquioxane-based polymer is formed, which can further improve the non-stick ability of the ceramic coating, and is suitable for cookware of this type.According to an exemplary embodiment, the release material can include the microspheres 11 having a porous structure formed by the abrasive particle stack described above with reference to FIG. 3, and the silicone oil 12o combined (e.g., adsorbed, bonded) in the porous structure of the microspheres 11. According to the present application, the release material in the present embodiment can be formed using the aforementioned method of preparing a release material. The preparation of the ceramic coating can be performed after the ceramic coating precursor and the release material are prepared, and the release material can be mixed with the ceramic coating precursor to prepare the ceramic coating according to an exemplary embodiment. According to an exemplary embodiment, in the preparation of the ceramic coating, 61-92 parts by weight of the ceramic coating precursor can be mixed with 5-30 parts by weight of the release material based on the total weight of the ceramic coating. In the ceramic coating precursor, the weight ratio of the first coating, the second coating, and the third coating can be (20-30) : (40-60) : (1-2), and after the ceramic coating precursor and the release material are mixed, the mixture can be stirred and reacted at a rotation speed of 120-200 rpm for 6-8 h, thereby obtaining the desired ceramic coating precursor. It can be appreciated that the content of the release material in the modified ceramic coating is approximately between 5 wt% and 32 wt%. According to the fifth aspect of the present application, another method of preparing a modified ceramic coating is provided, wherein the method includes: Step S31, preparing a first coating, a second coating, a third coating, and a release material, wherein: the first coating includes a siloxane monomer; the second coating includes a silica sol and a filler as essential components, and optionally a pigment, a wetting agent, a thickening agent, and an emulsifier as non-essential components, and a solvent; the third coating includes an organic acid as an essential component, and optionally a pH buffer and a catalyst as non-essential components; the release material is the release material provided in each of the above embodiments; Step S32, mixing the second coating and the third coating, and adjusting the pH of the mixture to be less than or equal to 4, thereby obtaining a first material; and Step S33, mixing the first coating and the release material with the first material, thereby obtaining the modified ceramic coating.Further, although the above describes a method of preparing a modified ceramic coating by separately preparing a ceramic coating precursor and a release material and mixing the ceramic coating precursor with the release material to obtain the modified ceramic coating, in a method of combining the step of preparing the ceramic coating precursor with the step of preparing the release material, as above, after mixing the second coating with the third coating, the first coating can be added to the mixture of the second coating and the third coating at the same time as the release material. For example, 40-60 parts by weight of the second coating can be mixed with 1-2 parts by weight of the third coating, thereby adjusting the pH of the mixture to less than or equal to 4 using the acidity of the third coating to obtain the first material. Then, the first coating and the release material can be added to the mixture, where the parts by weight ratio of the amounts added between the first coating, the release material, and the second coating can be in the range of (20-30):(5-30):(40-60). After mixing, the mixture can be stirred at a speed of 120-200 rpm for 6-8 h, thereby obtaining the desired modified ceramic coating. Through the above detailed description combining the exemplary embodiments, the ceramic coating of the inventive concept includes a release material including a pore structure formed by the accumulation of the wear-resistant particles, and since the pore structure formed by the accumulation of the wear-resistant particles can form a disordered multi-pore and / or a layered structure, the silicone oil is adsorbed to the pore structure formed by the accumulation of the wear-resistant particles to form the release material having a release effect. During cooking, the release of the silicone oil is slowed, thereby maintaining a long-lasting non-stick effect. According to the sixth aspect of the present application, a non-stick coating layer is provided for use in cookware, particularly for use in a frying pan, a soup pot, a pan, or the like, or for use in an inner container of a rice cooker or an inner container of a pressure cooker, where the non-stick coating layer is formed by air spraying a modified ceramic coating according to the modified ceramic coating provided according to the above various embodiments, or is formed by a modified ceramic coating prepared by the method of preparing the modified ceramic coating provided according to the above various embodiments. Referring to FIG. 5, the cookware includes a cookware body 100 and a non-stick coating layer 40 formed on the inner surface of the cookware body 100, the non-stick coating layer 40 is a modified layer formed by the modified ceramic coating, the modified layer is a single layer structure, and in the modified layer, a ceramic layer formed by a ceramic coating precursor and a release material dispersed in the ceramic layer. In some embodiments, the non-stick coating layer includes at least two sub-layers, i.e., the non-stick coating layer is a multi-layer structure.In the direction from the inner surface of the cookware body to the outside, the content of the release material in each sub-layer is increased. Alternatively, the molecular weight of the silicone oil in each sub-layer is different, and the molecular weight of the silicone oil is increased in the direction from the inside to the outside. Referring to FIG. 6, the non-stick coating 40 includes a first sub-layer 41 and a second sub-layer 42, the first sub-layer 41 is connected with the cookware body 100, the second sub-layer 42 is arranged on the first sub-layer 41, and the content of the release material included in the first sub-layer 41 is lower than the content of the release material included in the second sub-layer 42. In these embodiments, in the direction from the inside to the outside, that is, in the direction from the inner surface of the cookware body to the outside, by making the content of the release material be distributed in a gradient, the coating can maintain the non-stick ability for a longer time. As the outer layer of release material is consumed, the inner layer of release material will gradually supplement to the outer layer, ensuring that the coating always has sufficient non-stick performance. At the same time, the bottom layer is in direct contact with the cookware body, so it needs to have excellent adhesion and durability. In order to ensure the close combination between the coating and the cookware body, the silicone oil content of the bottom layer is relatively low, which can reduce the risk of separation between the coating and the cookware body caused by the expansion or penetration of silicone oil. In the direction from the inside to the outside, the molecular weight of the silicone oil in each sub-layer is increased in turn, because the greater the molecular weight, the higher the degree of combination in the release material, in this way, the release time of the silicone oil in the non-stick coating can be greatly increased, and the long-lasting non-stick performance is improved. According to the present application, the non-stick coating is formed by air spraying of the modified ceramic coating, and as an example, the parameters of air spraying include: the spraying distance is 140mm-180mm; the air pressure is 0.2MPa-0.4MPa; the flow rate is 5L / min-10L / min. In the process of forming the non-stick coating, the microspheres in the modified ceramic coating can still maintain this microsphere structure, and form a uniform film on the substrate together with the ceramic coating, and after sintering and solidification, the microspheres filled with silicone oil are evenly distributed in the non-stick coating. According to the present application, it also includes the step of curing the non-stick coating sprayed by air, and as an example, the non-stick coating can be cured by sintering, in particular, the sintering temperature is 200°C-300°C, and the time is 8-15 minutes, so as to improve the overall quality of the non-stick coating. According to the present application, the thickness of the non-stick coating is in the range of 30 microns-60 microns.According to the seventh aspect of the present application, a cookware is provided, wherein the cookware comprises a cookware body and a non-stick coating layer formed on the inner surface of the cookware body, wherein the non-stick coating layer is formed by air spraying the modified ceramic coating provided according to the above various embodiments, or is formed by the modified ceramic coating prepared by the method for preparing the modified ceramic coating provided according to the above various embodiments. In some embodiments, the inner surface of the cookware body is a rough surface, which can be obtained by sanding the inner surface of the cookware body, and in other embodiments, a rough transition layer is provided between the cookware body and the non-stick coating layer, which can further improve the bonding strength between the coating layer and the cookware body. As an example, the rough transition layer can be formed by thermal spraying a metal material on the surface of the cookware body 100. As shown in FIG. 7, a rough transition layer 50o is provided between the cookware body 100 and the non-stick coating layer 40. In some embodiments, a cover layer is further provided outside the non-stick coating layer to cover the surface and surface pores of the non-stick coating layer, wherein the cover layer is formed of silicone oil, grease or other ceramic coating different from the components of the modified ceramic coating. On the one hand, the cover layer can further improve the non-stick effect, and on the other hand, the cover layer can prevent food residues or grease from penetrating into the interior of the coating layer, affecting the non-stick property and service life of the non-stick coating layer. Referring to FIG. 8, the cookware comprises a cookware body 100 and a non-stick coating layer 40 formed on the inner surface of the cookware body 100, the non-stick coating layer 40 is a modified layer formed of the modified ceramic coating, and the modified layer is a single-layer structure, wherein the non-stick coating layer 40 comprises a ceramic layer formed of ceramic coating precursors and a slow-release material dispersed in the ceramic layer. A cover layer 60 is further provided outside the non-stick coating layer to cover the surface and surface pores of the non-stick coating layer 40. The beneficial effects of the present inventive concept will be described in conjunction with specific examples below. Example 1 forms a ceramic coating by the following method.

[0002] S100, mix and stir 80wt% of methyltrimethoxysilane and 20wt% of ethyl silicate to obtain a first coating.

[0003] S200, 30wt% of Akzonobel 1050 (silica sol), 8wt% of titanium dioxide (pigment), 25wt% of kaolin (filler), 3wt% of Tween-80 (emulsifier), Iwt% of water-based modified bentonite (thickening agent), 0.3wt% of polyoxyethylene TRITON X-100 C wetting agent, 20wt% of isopropyl alcohol, and the balance of deionized water are mixed uniformly, then added to a grinder and ground for 2h, to fully disperse and grind to a particle size of no more than 15 microns, to obtain a second coating.

[0004] S300, 48 parts by weight of formic acid, 48 parts by weight of acetic acid, 1 part by weight of boric acid (buffer), 0.5 parts by weight of acetic acid (catalyst) are mixed uniformly, to obtain a third coating.

[0005] S400, take 500nm-900nm particle size of magnetite as wear-resistant particles, and mix 98:2 by weight of polyvinyl alcohol-based binder, and then add deionized water as a grinding medium, and grind for 6h to obtain a uniformly dispersed mixed slurry, then spray granulation through a spray drying tower to obtain wet microspheres, add the microspheres to a vacuum furnace, and then sinter at a temperature of 1000°C for 15h. The sintered powder is sieved by a vibrating screen to obtain spherical or spheroidal microspheres with a particle size of 10-25 microns. Then, hydroxyl silicone oil with a molecular weight of 3000 is used as a silicone oil impregnant for microspheres with a pre-set pore structure, wherein the porosity of the pore structure of the microspheres is 50%, and the size of a single pore is 450-850nm. Control the filling amount of the silicone oil to obtain a sustained-release material with a silicone oil content of 50%.

[0006] S500, the above four coatings are mixed in the order of first coating: second coating: third coating: release material = 20:40:1:30 according to the weight ratio, and then rolling curing to obtain the ceramic coating. The mixing order and curing method are as follows: first, 40 parts by weight of the second coating and 1 part by weight of the third coating are mixed uniformly to adjust the pH to 4 by using the third coating, and then rolling dispersion for 0.5h, then 20 parts by weight of the first coating is added and shaken uniformly, then 30 parts by weight of the release material is added, and stirring reaction is carried out at 200rpm for 8h, to obtain a modified ceramic coating with a content of release material of about 33%, and by conversion, the content of silicone oil in the modified ceramic coating is about 16.5%. The above modified ceramic coating is used to manufacture a non-stick pan by the following method.

[0007] S600: substrate treatment. The stainless steel substrate is sandblasted with 60# brown corundum to form a roughness of 3 microns on the surface;

[0008] S700: preheating. The sandblasted substrate is cleaned and preheated to 60°C;

[0009] S800: spraying. The modified ceramic coating is sprayed by air spraying, and the film thickness is 40 microns; the air spraying parameters are as follows: spraying distance is 160mm; air pressure is 0.3MP; wear-resistant particle accumulation forms a pore structure; flow rate is 8L / min.

[0010] S900: sintering. The non-stick pan of Example 1 was obtained by the above method. Example 2 was obtained by the same method as Example 1 except that different abrasive particles were used in Step S400 (wherein the microspheres of this example were formed using carbide particles of iron as abrasive particles). Example 3 was obtained by the same method as Example 1 except that different abrasive particles were used in Step S400 (wherein the microspheres of this example were formed using nitride particles of titanium as abrasive particles). Example 4 was obtained by the same method as Example 1 except that different abrasive particles were used in Step S400 (wherein the microspheres of this example were formed using a mixture of 70% magnetite particles and 30% alumina particles as abrasive particles). Example 5 was obtained by the same method as Example 1 except that different abrasive particles were used in Step S400 (wherein the microspheres of this example were formed using a mixture of 40% magnetite particles and 60% alumina particles as abrasive particles). Example 6 was obtained by the same method as Example 1 except that different abrasive particles were used in Step S400 (wherein the microspheres of this example were formed using a mixture of 98% magnetite particles and 2% alumina particles as abrasive particles). Example 7 was obtained by the same method as Example 1 except that different silicone oil was used in Step S400 (wherein the hydroxyl silicone oil of this example was composed of 20 wt% hydroxyl silicone oil having a molecular weight of 800, 60 wt% hydroxyl silicone oil having a molecular weight of 3000, and 20 wt% hydroxyl silicone oil having a molecular weight of 12000). Example 8 was obtained by the same method as Example 1 except that different silicone oil was used in Step S400 (wherein the hydroxyl silicone oil of this example was composed of 30 wt% hydroxyl silicone oil having a molecular weight of 800, 40 wt% hydroxyl silicone oil having a molecular weight of 3000, and 30 wt% hydroxyl silicone oil having a molecular weight of 12000).Example 9 Except that a different silicone oil was used in step S400 (in which the hydroxyl silicone oil of the present example was composed of 25 wt% of a hydroxyl silicone oil having a molecular weight of 800, 50 wt% of a hydroxyl silicone oil having a molecular weight of 3000, and 25 wt% of a hydroxyl silicone oil having a molecular weight of 12000), the pot of Example 9 was manufactured using the same method as Example 1. Example 10 Except that a different silicone oil was used in step S400 (in which the silicone oil of the present example was a methyl silicone oil), the pot of Example 10 was manufactured using the same method as Example 1. Example 11 Except that the four kinds of coating materials above were sequentially mixed in a weight ratio of first coating material: second coating material: third coating material: release material = 30:60:2:20 in step S500, the pot of Example 11 was manufactured using the same method as Example 1. Example 12 Except that the four kinds of coating materials above were sequentially mixed in a weight ratio of first coating material: second coating material: third coating material: release material = 30:60:2:5 in step S500, the pot of Example 12 was manufactured using the same method as Example 1. Example 13 Except that the microspheres were pre-treated before silicone oil impregnation in step S400 (the surface of the microspheres was modified using an aqueous solution of silane coupling agent KH-570 having a mass concentration of 0.5%, and, in the present example, the content of silicone oil in the release material was 60%), the pot of Example 13 was manufactured using the same method as Example 1. Example 14 Except that microspheres having different pore structures were formed using different particle sizes of wear-resistant particles in step S400 (in the present example, Fe3O4 having a particle size of 1.5 microns - 3 microns was used as the wear-resistant particles, the microspheres obtained had a pore structure with a porosity of 60% and a single pore size of 1 micron - 2 microns, and the content of silicone oil was controlled to obtain a release material having a silicone oil content of 50%), the pot of Example 14 was manufactured using the same method as Example 1. Example 15 Except that microspheres having different pore structures were formed using different particle sizes of wear-resistant particles in step S400 (in the present example, Fe3O4 having a particle size of 100 nanometers - 500 nanometers was used as the wear-resistant particles, the microspheres obtained had a pore structure with a porosity of 30% and a single pore size of 30 nanometers - 450 nanometers), the pot of Example 15 was manufactured using the same method as Example 1.The amount of silicone oil was controlled to obtain a slow-release material having a silicone oil content of 50%, and a pot of Example 15 was manufactured using the same method as in Example 1. Comparative Example 1 differs from Example 1 in that the S400 step was omitted. That is, in step S500, the first coating material, the second coating material, the third coating material, and the silicone oil were mixed in the order of the weight ratio 20:40:1:30, and the resulting ceramic material was used to manufacture a pot of Comparative Example 1. Comparative Example 2 differs from Example 1 in that the S400 step was omitted, and in step S500, the first coating material, the second coating material, the third coating material, and the silicone oil were mixed in the order of the weight ratio =30:60:2:20, and the resulting ceramic material was used to manufacture a pot of Comparative Example 2. Comparative Example 3 differs from Example 1 in that the S400 step was omitted, and in step S500, the first coating material, the second coating material, the third coating material, and the silicone oil were mixed in the order of the weight ratio =30:60:2:5, and the resulting ceramic material was used to manufacture a pot of Comparative Example 3. In Comparative Example 4, a different slow-release material was used in step S400 (in which 58 parts by weight of a hydroxyl silicone oil having a molecular weight of 3000 was mixed with 60 parts by weight of a vermiculite having a particle size of 100 mesh to 3000 mesh, 3 parts by weight of a methoxysilane coupling agent was added and uniformly mixed, and then ground to a particle size of not greater than 30 micrometers, 0.3 parts by weight of a titanate was added, and further ground to a particle size of not greater than 20 micrometers, and then treated with ultrasonic waves at room temperature of 22°C for 0.5 h, thereby obtaining a slow-release particle, and the particle size of the slow-release particle followed a normal distribution), and a pot of Comparative Example 4 was manufactured using the same method as in Example 1. In Comparative Example 5, a different slow-release material was used in step S400 (in which 58 parts by weight of a hydroxyl silicone oil was mixed with 60 parts by weight of a vermiculite having a particle size of 100 mesh to 3000 mesh, and the hydroxyl silicone oil was composed of 25 wt% of a hydroxyl silicone oil having a molecular weight of 800, 50 wt% of a hydroxyl silicone oil having a molecular weight of 3000, and 25 wt% of a hydroxyl silicone oil having a molecular weight of 1200.The hydroxyl silicone oil mixture is mixed, then 3 parts by weight of methoxysilane coupling agent is added and mixed uniformly, and then ground to a particle size of not more than 30 microns. Then, 0.3 parts by weight of titanate is added and ground to a particle size of not more than 20 microns. Then, ultrasonic treatment is performed at room temperature of 22 °C for 0.5 h to obtain the slow-release particles, and the particle size of the slow-release particles obeys normal distribution. The same method as in Example 1 is used to manufacture the cookware of Comparative Example 5.

[0011] (1) Test method for persistent non-stickiness: refer to the egg frying non-stickiness test in GB T 32095.2-2015 4.2.1, the unit is times, the higher the number, the longer the service life, 500 times of evaluation of non-stickiness, and the number of times when the non-stickiness is recorded to III level. It can be seen from the comparison and analysis of the embodiments 1-15 of the inventive concept and the comparative examples 1-5 that: under the condition of a certain type of silicone oil and filling amount, the long-lasting non-stickiness is best with ferric oxide as the main material. Under the condition that the content of silicone oil with medium molecular weight is more than 50%, the silicone oil in the form of a mixture of macromolecules, medium molecules and small molecules can optimize the non-stickiness to a certain extent, while under the condition that the content of silicone oil with medium molecular weight is less than 50%, the addition of macromolecules and small molecules will have an adverse effect on the long-lasting non-stickiness. It can be seen from embodiments 1 and 10 that the long-lasting non-stickiness of hydroxyl silicone oil is better than that of methyl silicone oil. It can be seen from embodiments 1, 14 and 15 that under the condition that the type of silicone oil and the filling amount are the same, the long-lasting non-stickiness of the non-stick coating corresponding to the pore structure is in a normal distribution, the long-lasting non-stickiness of the pore size and the pore rate in the middle is best, and although the minimum pore size and the pore rate decrease in the long-lasting non-stickiness, the decrease is small, while the pore size and the pore rate of a larger level are not conducive to the long-lasting release of silicone oil, and the silicone oil is easy to flow out in a short cooking time and lose the non-stickiness. Although one or more embodiments of the present application have been described with reference to the accompanying drawings, it will be understood by those skilled in the art that various changes in form and details can be made therein without departing from the spirit and scope of the claimed application.

Claims

CLAIM 1. A slow-release material, characterized by, The slow-release material includes: a microsphere having a pore structure, the microsphere having the pore structure being formed by spray drying of a mixed slurry including wear-resistant particles and a binder; silicone oil filled in the pore structure of the microsphere; wherein the wear-resistant particles include a main material including at least one of a ferric oxide particle, a carbide particle of iron, a carbide particle of titanium, a carbide particle of cobalt, a carbide particle of nickel, a nitride particle of iron, a nitride particle of titanium, a nitride particle of aluminum, a nitride particle of cobalt, and a nitride particle of nickel.

2. The slow-release material according to claim 1, characterized by The wear-resistant particles further include an auxiliary material including at least one of an alumina particle, a titania particle, a cupric oxide particle, a nickel oxide particle, a silica particle, a nickel oxide particle, and a cobalt oxide particle.

3. The slow release material according to claim 2, characterized in that, The main material accounts for 50-98% by weight of the total weight of the microsphere, with the balance being the auxiliary material.

4. The slow-release material according to any one of claims 1 to 3, characterized in that The particle diameter of the wear-resistant particles is 100 nm to 3 μm; and / or the particle diameter of the slow-release material is 10 μm to 25 μm; and / or the porosity of the pore structure is 30-60%, and the size of a single pore is 30 nm to 1 μm; and / or in the microsphere, the contact portions of the wear-resistant particles in contact with each other are interlocked; and / or the slow-release material has a spherical or spheroidal structure.

5. The slow-release material according to any one of claims 1 to 4, characterized in that The silicone oil includes 20-30% low-molecular-weight silicone oil, 40-60% medium-molecular-weight silicone oil, and 20-30% high-molecular-weight silicone oil, in terms of weight percentage, wherein the low-molecular-weight silicone oil has a molecular weight of 500-1000, the medium-molecular-weight silicone oil has a molecular weight of 3000-6000, and the high-molecular-weight silicone oil has a molecular weight of 12000-30000.

6. The slow-release material according to any one of claims 1 to 5, characterized in that The microsphere further has a carbonization product of the binder, the carbonization product of the binder being attached to a portion of the surface of the wear-resistant particles, and the weight ratio of the carbonization product of the binder to the wear-resistant particles in the microsphere is (0.5-1):98 7. A method of preparing a slow release material, characterized by, The method includes: 29 A sustained-release material is prepared by spray-drying a mixed slurry including a wear-resistant particle and a binder to form a microsphere having a pore structure; and filling silicon oil into the pore structure of the microsphere, wherein the wear-resistant particle includes a bulk material including at least one of a ferrite particle, a carbide particle of iron, a carbide particle of titanium, a carbide particle of tungsten, a carbide particle of chromium, a nitride particle of iron, a nitride particle of titanium, a nitride particle of aluminum, a nitride particle of chromium, and a nitride particle of cobalt.

8. The method of claim 7, characterized in that The microsphere is pre-treated to change a charge state of a surface before the step of filling the silicon oil, and then the step of filling the silicon oil is performed.

9. A modified ceramic coating, characterized by, The modified ceramic coating includes a ceramic coating precursor and a sustained-release material dispersed in the ceramic coating precursor, wherein the sustained-release material is the sustained-release material according to any one of claims 1 to 6 or is the sustained-release material prepared by the method of preparing a sustained-release material according to claim 7 or 8.

10. The modified ceramic coating of claim 9, wherein, The weight ratio of the sustained-release material to the ceramic coating precursor is (5-30) : (61-92).

11. A method of preparing a modified ceramic coating, characterized in that The method includes: providing a ceramic coating precursor; providing the sustained-release material according to any one of claims 1 to 6 or prepared by the method of preparing a sustained-release material according to claim 7 or 8; and mixing the ceramic coating precursor and the sustained-release material to obtain the modified ceramic coating.

12. The method according to claim 11, characterized in that The step of providing the ceramic coating precursor includes: providing a first coating including a siloxane monomer; providing a second coating including a silica sol; providing a third coating including an organic acid; mixing the second coating and the third coating to obtain a first mixed material, so that the pH of the first mixed material is adjusted to be between 2 and 4; and mixing the first coating and the first mixed material to form the ceramic coating precursor.

13. A non-stick coating, characterized in that the non-stick coating is formed by the modified ceramic coating according to claim 9 or 10, or is formed by the modified ceramic coating prepared by the method of preparing a modified ceramic coating according to claim 11 or 12. 30 The non-stick coating includes at least two sub-layers.

14. The non-stick coating according to claim 13, characterized in that ​ Among them, in the direction from inside to outside, the content of the release material in each sub-layer is increasing; or the molecular weight of the silicone oil in each sub-layer is different, and the molecular weight of the silicone oil is increasing.

15. A cooker characterized by comprising: a cooking chamber; a heating unit; a control unit; a temperature sensor; and a temperature control unit. The cookware comprises a cookware body and a non-stick coating formed on the inner surface of the cookware body, wherein the non-stick coating is the non-stick coating according to claim 13 or 14.

16. The cooker according to claim 15, characterized in that, The non-stick coating is further provided with a covering layer to cover the surface and surface pores of the non-stick coating, wherein the covering layer is formed of silicone oil, grease or other vitrified coating different from the components of the modified ceramic coating.

17. The cookware according to claim 15 or 16, characterized in that The inner surface of the cookware body is a rough surface or a rough transition layer is provided between the cookware body and the non-stick coating.

Images