Ceramic coating and non-stick utensils including ceramic coating

Abstract

A ceramic coating and a non-stick utensil including the ceramic coating are provided. The ceramic coating comprises: a first ceramic coating layer comprising a ceramic coating precursor and slow-release particles dispersed in the ceramic coating precursor; and a second ceramic coating layer disposed on the first ceramic coating layer and comprising the second ceramic coating. The slow-release particles comprise a slow-release material and silicone oil bound to the slow-release material. The slow-release material comprises at least one of vermiculite, zeolite, bentonite, diatomaceous earth, alpha alumina, silica aerogel, fumed silica, amorphous silica, hollow glass powder, porous silicate, layered silicate, porous phosphate, layered phosphate, porous carbonate, layered carbonate, porous sulfate, and layered sulfate.

Description

Technical Field

[0001] The present invention relates to a ceramic coating and a non-stick utensil comprising the ceramic coating. Background Art

[0002] Currently, non-stick coatings primarily fall into two categories: PTFE and ceramic. Ceramic coatings, however, are subject to significant limitations due to their short lifespan. They are far less widely used than PTFE and fall short of consumers' daily demands for non-stick utensils. For example, a typical non-stick pan will begin to stick after about a month of use. This is especially true with high-temperature cooking methods like Chinese cooking, and with the wear of metal spatulas, which can cause the non-stick properties to degrade rapidly.

[0003] Therefore, improving the long-lasting non-stick properties of ceramic coatings has become a very meaningful and urgent technical need. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a ceramic coating including a first ceramic coating containing slow-release particles and a second ceramic coating as a sealing layer, and a non-stick utensil including the ceramic coating.

[0005] According to one aspect of the exemplary embodiment, a ceramic coating includes: a first ceramic coating formed using a first ceramic paint, the first ceramic paint including a ceramic paint precursor and slow-release particles dispersed in the ceramic paint precursor; and a second ceramic coating disposed on the first ceramic coating and formed using the second ceramic paint. The slow-release particles include a slow-release material and silicone oil bound to the slow-release material. The slow-release material includes at least one of vermiculite, zeolite, bentonite, diatomaceous earth, alpha alumina, silica aerogel, fumed silica, amorphous silica, hollow glass powder, porous silicate, layered silicate, porous phosphate, layered phosphate, porous carbonate, layered carbonate, porous sulfate, and layered sulfate.

[0006] The particle size of the sustained-release particles may be less than or equal to 20 microns.

[0007] The first ceramic coating may have a thickness of 10 microns to 80 microns.

[0008] The second ceramic coating may have a thickness of 8-20 microns.

[0009] The slow-release particles may be included in an amount of 5.15-32.97 parts by weight per 100 parts by weight of the first ceramic coating.

[0010] The silicone oil may include, by weight, 20% to 30% of a low molecular weight silicone oil, 40% to 60% of a medium molecular weight silicone oil, and 20% to 30% of a high molecular weight silicone oil. The low molecular weight silicone oil has a molecular weight between 500 and 1000, the medium molecular weight silicone oil has a molecular weight between 3000 and 6000, and the high molecular weight silicone oil has a molecular weight between 12000 and 30000.

[0011] The ceramic coating precursor may include the same material as the second ceramic coating.

[0012] The first ceramic coating may include at least a first sublayer and a second sublayer stacked on each other.

[0013] The first sub-layer may be below the second sub-layer, and the content of the sustained-release particles included in the first sub-layer may be lower than the content of the sustained-release particles included in the second sub-layer.

[0014] According to another aspect of the exemplary embodiment, a non-stick utensil includes a base body and the ceramic coating as described above disposed on the base body.

[0015] The present invention provides a first ceramic coating by adding slow-release particles comprising a slow-release material to a ceramic coating. Because the slow-release material has a disordered porous and / or layered structure, silicone oil can bind to the slow-release material. Therefore, during cooking, the porous and / or layered structure of the slow-release material can slow the release of silicone oil, thereby maintaining a long-lasting non-stick effect. Furthermore, the present invention provides a second ceramic coating formed from a conventional ceramic material as a sealing layer, further slowing the release of silicone oil to maintain the ceramic coating's sustained non-stick properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram illustrating a ceramic coating according to an exemplary embodiment;

[0017] Figure 2 is an enlarged view showing slow-release particles in a ceramic coating according to an exemplary embodiment. DETAILED DESCRIPTION

[0018] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout.

[0019] Ceramic coatings achieve their non-stick properties primarily through the use of silicone methyl groups and the addition of silicone oil. As the product is exposed to heat and wear during use, the silicone oil in the coating is gradually lost, damaging the silicone methyl groups on the surface and ultimately losing the non-stick effect, leading to sticking in cooking. If ceramic coatings could be made to continuously store oil, they could form an effective oil film that isolates food from the coating surface, achieving long-lasting non-stick properties.

[0020] Therefore, the present invention provides a ceramic coating having a first ceramic coating and a second ceramic coating, wherein the first ceramic coating includes slow-release particles containing a slow-release material, and the slow-release material can have a disordered porous and / or layered structure, and the silicone oil is combined (e.g., adsorbed, bonded) to the slow-release material, so that during the cooking process, the slow-release particles slow down the release of the silicone oil, thereby maintaining the long-lasting non-stick effect of the first ceramic coating. In addition, since the ceramic coating also includes a second ceramic coating as a sealing layer, the release of the silicone oil in the ceramic coating can be further slowed down, thereby further enhancing the non-stick effect. However, the exemplary embodiment is not limited thereto, and those skilled in the art can apply the ceramic coating to any existing technical field suitable for non-stick based on the concept of the present invention.

[0021] Figure 1 is a schematic diagram illustrating an embodiment of a ceramic coating according to an exemplary embodiment, Figure 2 is a schematic diagram showing slow-release particles in a ceramic coating according to an exemplary embodiment. Figure 1 and Figure 2 The ceramic coating of the present invention is described.

[0022] The ceramic coating according to the present inventive concept may include a first ceramic coating and a second ceramic coating.

[0023] First ceramic coating

[0024] Reference Figure 1 and Figure 2 As shown, the first ceramic coating 200 according to an exemplary embodiment of the present inventive concept is formed using a first ceramic material and disposed on a substrate 100 . The first ceramic material includes a ceramic coating precursor 1 and slow-release particles 2 dispersed in the ceramic coating precursor.

[0025] According to an exemplary embodiment, the substrate 100 may be a substrate known in the art for making cookware, and may include a stainless steel substrate, an iron substrate, an aluminum substrate, a titanium substrate, etc. However, the present invention is not limited to the material, application, or other properties of the substrate. In other words, those skilled in the art may use any material requiring a ceramic coating as the substrate 100 as needed. Thus, the non-stick utensils of the present invention can be applied to any scenario requiring non-stick properties (such as non-stick coatings for cooking utensils (e.g., frying pans, rice cooker inner pots), interior and exterior coatings for transportation pipelines, etc.).

[0026] The first ceramic coating layer 200 is located on the substrate 100. The first ceramic coating layer 200 is formed using the first ceramic coating, and thus may include a ceramic coating precursor 1 and slow-release particles 2.

[0027] At least one of the ceramic coating precursor 1 and the second ceramic coating included in the second ceramic coating 300, described below, can be a ceramic coating commonly used in the art. Therefore, it can have the same ingredients as ceramic coatings commonly used in the art, and thus can be produced using methods known in the art for producing ceramic coatings. However, exemplary embodiments are not limited thereto. As described below in conjunction with exemplary embodiments of the present invention regarding the method for producing a first ceramic coating using a first ceramic coating, at least one of the ceramic coating precursor and the second ceramic coating can be a ceramic coating precursor prepared during the production of the first ceramic coating according to the present invention (and comprise the same material). The ceramic coating precursor 1 produced using the method described below can exhibit superior non-stick properties when combined with the slow-release particles.

[0028] The slow-release particles 2 dispersed in the ceramic coating precursor 1 include a slow-release material 21 and silicone oil 22 bound to the slow-release material.

[0029] According to an exemplary embodiment, the slow-release material 21 may have a layered and / or porous structure, so that the silicone oil 22 may, for example, be bonded to the surface of the slow-release material and / or adsorbed within the pores and / or layered structure. According to an example, the slow-release material 21 may include at least one of vermiculite, zeolite, bentonite, diatomaceous earth, alpha alumina, silica aerogel, fumed silica, amorphous silica, hollow glass micropowder, porous silicate, layered silicate, porous phosphate, layered phosphate, porous carbonate, layered carbonate, porous sulfate, and layered sulfate. The slow-release material 21 has a porous and / or layered structure and is combined with silicone oil. Therefore, the silicone oil 22 combined with the slow-release material 21 can be slowly released during use of a cookware having a non-stick coating formed by the ceramic coating of the present invention, thereby greatly improving the long-lasting non-stick properties of the non-stick coating formed by the ceramic coating.

[0030] According to an exemplary embodiment, silicone oil 22 is bound (e.g., adsorbed or bonded) to the sustained-release material 21 and provides the primary non-stick properties of the ceramic coating. Silicone oil 22 can be selected from at least one of methyl silicone oil, dimethyl silicone oil, hydroxy silicone oil, hydrogen silicone oil, and polyether-modified silicone oil. Furthermore, by weight, silicone oil 22 can include 20%-30% low-molecular-weight silicone oil, 40%-60% medium-molecular-weight silicone oil, and 20%-30% high-molecular-weight silicone oil. The low-molecular-weight silicone oil can have a molecular weight between 500-1000, the medium-molecular-weight silicone oil can have a molecular weight between 3000-6000, and the high-molecular-weight silicone oil can have a molecular weight between 12,000-30,000. Silicone oil 22 can be prepared using a blend of different molecular weights. This is because: high-molecular-weight silicone oils bond more firmly to the sustained-release material and release more slowly; low-molecular-weight silicone oils are more mobile, resulting in better non-stick properties; and medium-molecular-weight silicone oils offer a balance between mobility and strong bonding. Therefore, by combining low molecular weight silicone oil, medium molecular weight silicone oil and high molecular weight silicone oil, the sustained release and non-stick effects can be better exerted.

[0031] In addition, in order to improve the bonding strength between the silicone oil and the slow-release material, a coupling agent may be provided between the slow-release material and the silicone oil. Here, the coupling agent may include a silane coupling agent. However, the exemplary embodiment is not limited thereto, and the coupling agent may be omitted.

[0032] Preferably, the particle size of the sustained-release particles according to an exemplary embodiment may be less than or equal to 20 microns. This is because an excessively large particle size (eg, greater than 20 microns) may have a significant impact on the appearance of the formed non-stick coating.

[0033] According to an exemplary embodiment, the first ceramic coating 200 may include 5.15-32.97 parts by weight of slow-release particles per 100 parts by weight of the first ceramic coating 200. This is because, when the ceramic coating precursor is excessive, the slow-release particle content is relatively low, resulting in a poor slow-release effect. However, when the slow-release particle content is relatively high, the coating's strength and bonding strength are likely to be reduced.

[0034] Figure 1 A single-layer first ceramic coating 200 is shown applied on the substrate 100 , however, exemplary embodiments are not limited thereto, that is, the first ceramic coating may also include at least two sub-layers (eg, two or three layers, etc.) of ceramic coatings.

[0035] Furthermore, when the first ceramic coating 200 is a single layer, the thickness of the single layer of the first ceramic coating 200 can be within a range of 10 to 80 microns. This is because, when the thickness of the first ceramic coating 200 is less than 10 microns, the wear resistance is insufficient, and the first ceramic coating is easily worn out. Conversely, when the thickness of the first ceramic coating is greater than 80 microns, the coating becomes loose, thereby reducing the impact strength.

[0036] In addition, when the first ceramic coating 200 includes at least two sublayers, the at least two sublayers may be identical except for the content and particle size of the slow-release particles. For example, according to the example of including two sublayers, the first ceramic coating 200 may include a first sublayer (not shown) and a second sublayer (not shown) provided from the substrate 100, wherein the first sublayer includes a ceramic coating precursor and first slow-release particles, and the second sublayer includes a ceramic coating precursor and second slow-release particles. The content of the second slow-release particles may not be less than the content of the first slow-release particles, and the content of the second slow-release particles may be 5.15-32.97 parts by weight of the second slow-release particles per 100 parts by weight of the second sublayer. In this case, the content of the first slow-release particles may be 32.97 parts by weight or less of the first slow-release particles per 100 parts by weight of the first sublayer and less than the content of the second particles. In addition, when the first ceramic coating 200 includes at least two sublayers, the thickness of the sublayer including the slow-release particles may be no less than 10 microns, and the total thickness of the at least two sublayers (ie, the thickness of the first ceramic coating 200 ) may be no greater than 80 microns.

[0037] Second ceramic coating

[0038] The second ceramic coating 300 is located on the first ceramic coating 200 .

[0039] The second ceramic coating 300 can be formed using a second ceramic coating. The second ceramic coating can be the same as or different from the ceramic coating precursor in the first ceramic coating (e.g., it can include the same or different materials). Specifically, the second ceramic coating can differ from the first ceramic coating only in that the second ceramic coating does not include slow-release particles (or further, does not include a filler). The second ceramic coating can be a ceramic coating precursor formed during the preparation of the first ceramic coating, as described below, or prepared using the method for preparing a ceramic coating precursor. Alternatively, the second ceramic coating can be a ceramic coating commonly used in the art or prepared using a conventional formulation. For example, the second ceramic coating can be formulated using a silane substance, alkaline silica sol, and a non-sticking agent according to a conventional ratio.

[0040] The second ceramic coating 300 does not include slow-release particles and serves as a sealing layer to further slow down the release of silicone oil in the slow-release particles in the first ceramic coating 200. Therefore, the second ceramic coating 300 may have a thickness of 8-20 microns.

[0041] The ceramic coating structure including the first ceramic coating 200 and the second ceramic coating 300 according to the present invention is described above in conjunction with exemplary embodiments. Hereinafter, a method for preparing the ceramic coating including the first ceramic coating and the second ceramic coating will be described in detail.

[0042] The method of manufacturing a ceramic coating according to the present invention may include: providing a substrate 100; preparing a first ceramic coating and a second ceramic coating; forming a first ceramic coating 200 on the substrate 100 using the first ceramic coating using a layer-forming process; and forming a second ceramic coating 300 on the first ceramic coating 200 using the second ceramic coating using a layer-forming process.

[0043] According to an exemplary embodiment, the substrate 100 may be a substrate known in the art for making cookware, and may include a stainless steel substrate, an iron substrate, an aluminum substrate, a titanium substrate, etc. However, the present invention is not limited to the material, use, or other properties of the substrate. In other words, those skilled in the art may use any material on which a ceramic coating is to be applied as the substrate 100 as needed.

[0044] Before, during, or after providing the substrate 100 , the first ceramic coating and the second ceramic coating may be prepared.

[0045] Preparation of the first ceramic coating and the second ceramic coating

[0046] According to an exemplary embodiment, a first ceramic coating may include a ceramic coating precursor and slow-release particles 2 dispersed in the ceramic coating precursor. Therefore, the steps of preparing the first ceramic coating may include separately preparing the ceramic coating precursor 1 and the slow-release particles 2, and then mixing the ceramic coating precursor 1 with the slow-release particles 2 to obtain the first ceramic coating. However, exemplary embodiments are not limited thereto. In other words, those skilled in the art may also employ conventional ceramic coating preparation methods to obtain the ceramic coating precursor herein, or may combine the steps of preparing the ceramic coating precursor with the steps of preparing the slow-release particles. This conventional ceramic coating preparation method will not be redundantly described herein. The following will primarily describe a method for preparing the first ceramic coating according to the present invention by separately preparing the ceramic coating precursor and the slow-release particles.

[0047] According to an exemplary embodiment, the step of preparing the ceramic coating precursor may include a step of providing materials and a step of mixing.

[0048] The step of providing materials may include the steps of separately providing A material, B material, and C material.

[0049] Here, material A may include a silane substance, material B may include silica sol and filler as essential components, optional pigments, wetting agents, thickeners and emulsifiers as unnecessary components, and solvents, and material C may include an organic acid as an essential component, and optional pH buffers and catalysts (e.g., zirconium acetate) as unnecessary components.

[0050] In Material A, according to exemplary embodiments, a silane substance is used to form polysiloxane during the formation of the ceramic coating. Therefore, the silane substance here may include substances known in the art for polycondensation to form polysiloxane. According to exemplary embodiments, the silane substance may include at least one of methyltrimethoxysilane, methyltriethoxysilane, and dimethyldimethoxysilane, but is not limited thereto. Furthermore, in addition to the silane substance, Material A may also include tetraethyl orthosilicate, which polycondenses to form polysiloxane. In this case, the silane substance may comprise 80% to 97% of Material A by weight, and the tetraethyl orthosilicate may comprise 3% to 20% of Material A by weight.

[0051] Material B may necessarily include fillers and silica sol. Fillers enhance the wear resistance of the coating, among other things. Therefore, the present invention is not limited to the type of filler, and commonly used fillers may be selected. For example, at least one of mica powder, kaolin, montmorillonite, silicon carbide, aluminum oxide, and silicon dioxide may be selected. Furthermore, silica sol is the primary film-forming substance in ceramic coatings. It reacts with polysiloxane under acidic conditions to form a ceramic coating through a sol-gel reaction. Therefore, commercially available silica sol may be selected as the silica sol in Material B of the present invention. For example, the silica sol may be AkzoNobel 1050 (silica sol) or American Grace LUDIX AM-50.

[0052] The essential components of Material B can be dispersed in a solvent. That is, Material B can also include a solvent. Here, the solvent can include deionized water and, to regulate the solvent's volatilization rate during the coating drying process, can also include isopropyl alcohol. Furthermore, the ratio of isopropyl alcohol to water is unlimited, and the ratio of water to isopropyl alcohol can be selectively adjusted based on actual needs.

[0053] In addition to the essential components listed above, material B may optionally include one or more of a pigment, a wetting agent, a thickener, and an emulsifier as optional components. Pigments are primarily used to impart different colors to the coating, so common inorganic pigments can be used. Inorganic pigments offer excellent heat resistance and safety, and are therefore preferred for applications requiring high temperatures. According to exemplary embodiments, at least one of carbon black, copper chromium black, titanium dioxide, and iron oxide can be used as a filler. Furthermore, during the preparation of the essential components in a solvent, at least one of a wetting agent, a thickener, and an emulsifier can be added to the material to enhance its superior properties.

[0054] According to a specific example, the material B may include, by weight, 30-48 wt% of silica sol, 8-13 wt% of pigment, 8-25 wt% of filler, 0.2-1 wt% of wetting agent, 1-3 wt% of thickener, 3-5 wt% of emulsifier, and the balance being isopropyl alcohol and deionized water. However, exemplary embodiments are not limited thereto, and one or more of the unnecessary components may be omitted.

[0055] Material C serves as a strong acid catalyst and may include an organic acid as an essential component, and an optional pH buffer and catalyst (e.g., zirconium acetate) as optional components. The organic acid is used to adjust the pH of the silica sol in subsequent processes, enabling it to react with Material A in an acidic environment. Therefore, organic acids commonly used in ceramic coatings in the art can be used. According to exemplary embodiments, at least one of formic acid and acetic acid can be selected as the organic acid. When both formic acid and acetic acid are included, the weight ratio of formic acid to acetic acid can be between 4:6 and 1:1. Material C may also optionally include a pH buffer and catalyst. These pH buffers and catalysts can be known in the art for use in preparing strong acid catalysts for ceramic coatings. For example, the pH buffer can be a weak acid such as boric acid. The catalyst is used to accelerate the sol-gel reaction and can be zirconium acetate, for example. However, exemplary embodiments are not limited to the specific types of pH buffers and catalysts, and these can be omitted or appropriately selected based on existing knowledge.

[0056] According to an exemplary embodiment, the C material may 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 a zirconium acetate catalyst.

[0057] After providing the above-mentioned materials, a mixing step can be performed. In this article, the mixing step can include a first mixing step of mixing the B material with the C material and a second step of mixing the result of the first mixing step (ie, the first material described below) with the A material.

[0058] Specifically, 40-60 parts by weight of material B can be mixed with 1-2 parts by weight of material C, and the pH of the mixture can be adjusted to acidic (e.g., to less than or equal to 4) by utilizing the acidity of material C to obtain the first material. Since material C includes a solid filler and an optional pigment, before mixing or during the preparation of material C, material C can be added to a grinder and ground for 0.5-2 hours to fully disperse it and grind it to a particle size of less than or equal to 15 microns to obtain a uniformly dispersed slurry.

[0059] After the B material and the C material are mixed, the mixture may be tumbling dispersed for a predetermined time (eg, 0.5 h) so that the first material has a high degree of dispersion.

[0060] After obtaining the first material, material A can be added to the first material. Here, the weight ratio of material A to material B can be within a range of (20-30):(40-60). After adding material A, materials A and B can be shaken evenly to allow them to undergo a sol-gel reaction in an acidic environment, thereby forming a ceramic coating precursor.

[0061] During, before, or after the preparation of the ceramic coating precursor, the slow-release particles can be prepared. The slow-release particles can be prepared by mixing the slow-release material with silicone oil.

[0062] According to an exemplary embodiment, the sustained-release particles 2 may include a sustained-release material 21 having a pore structure and / or a lamellar structure and a silicone oil 22 bound (eg, adsorbed, bonded) to the sustained-release material.

[0063] A slow-release material precursor of appropriate size (i.e., the slow-release material before grinding, when the grinding step is omitted, the slow-release material precursor can be considered as the slow-release material for final use) can be selected to prepare slow-release particles. According to an exemplary embodiment, the slow-release material precursor can have a layer gap and / or pore structure. According to an example, the slow-release material precursor can include at least one of vermiculite, zeolite, bentonite, diatomaceous earth, alpha alumina, silica aerogel, fumed silica, amorphous silica, hollow glass powder, porous silicate, layered silicate, porous phosphate, layered phosphate, porous carbonate, layered carbonate, porous sulfate and layered sulfate. The slow-release material precursor has a porous and / or layered structure and the slow-release material formed after grinding is combined with silicone oil. The silicone oil combined with the slow-release material can be slowly released during the use of the cookware with the non-stick coating formed by the ceramic coating conceived by the present invention, thereby greatly improving the long-lasting non-stick performance of the non-stick layer formed by the ceramic coating.

[0064] According to an exemplary embodiment, the particle size of the sustained-release material precursor can be within the range of 100 mesh to 3000 mesh (100 mesh below the sieve and 3000 mesh above the sieve), and the particle size of the sustained-release material within this range can obey a normal distribution. However, when the particle size is too large (e.g., above the sieve of 100 mesh), the excessively large particle size can easily increase the grinding process or make the particle size of the sustained-release material after grinding too large, ultimately affecting the appearance of the non-stick coating made using the ceramic coating; conversely, when the particle size is too small (e.g., below the sieve of 3000 mesh, and the particle size becomes even smaller after grinding), it is not easy to effectively adsorb and bond with silicone oil, thereby making it difficult to achieve a good silicone oil sustained-release effect.

[0065] When the sustained-release material precursor has the above-described particle size distribution, the particle size of the resulting sustained-release material can be reduced to 20 microns or less using two grinding processes, as described below. However, exemplary embodiments are not limited thereto. Specifically, when the particle size of the sustained-release material precursor is selected to have a smaller value within the range of 100-3000 mesh, one grinding process can be omitted. Furthermore, when the particle size of the sustained-release material precursor is selected to have an even smaller value within the above-described range, both grinding processes can be omitted. When at least one of the grinding processes is omitted, the omitted grinding process can be replaced by a stirring process, or the mixture can be left untreated.

[0066] According to an exemplary embodiment, the silicone oil 22 is bound (e.g., adsorbed, bonded) to the sustained-release material 21 and provides the main non-stick properties for the ceramic coating. The silicone oil can be selected from at least one of methyl silicone oil, dimethyl silicone oil, hydroxy silicone oil, hydrogen silicone oil, and polyether-modified silicone oil, and can be mixed in a certain proportion by silicone oils of different molecular weights to form a silicone oil composition with a molecular weight normal distribution; wherein, by weight percentage, the low molecular weight silicone oil content can be 20wt%-30wt%, the medium molecular weight silicone oil content can be 40wt%-60wt%, and the high molecular weight silicone oil content can be 20wt%-30wt%. Here, the molecular weight of the low molecular weight silicone oil can be between 500-1000, the molecular weight of the medium molecular weight silicone oil can be between 3000-6000, and the molecular weight of the high molecular weight silicone oil can be between 12000-30000. By utilizing a normally distributed silicone oil composition, the sustained-release and non-stick effects can be better exerted. This is because: high molecular weight silicone oils bond more firmly to the sustained-release material, resulting in a slower release rate; low molecular weight silicone oils offer greater mobility, resulting in better non-stick properties; and medium molecular weight silicone oils offer a balance of mobility and strong bonding. Therefore, low, medium, and high molecular weight silicone oils can be combined to achieve better sustained-release and non-stick properties.

[0067] According to an example, 35-58 parts by weight of a slow-release material precursor can be mixed with 42-60 parts by weight of silicone oil to obtain a mixture, and 1 part by weight of a coupling agent (e.g., a methoxysilane coupling agent), 0.3 parts by weight of a catalyst (e.g., a titanate catalyst), and 1-1.5 parts by weight of a dispersant can be added to the mixture to prepare slow-release particles. Here, the coupling agent and the catalyst are used to enhance the binding force between the silicone oil and the slow-release material, and the dispersant is used to improve the dispersion of the slow-release material in the silicone oil. Therefore, the exemplary embodiment is not limited to the case where the coupling agent, the dispersant, and the catalyst are included, and at least one of the coupling agent, the catalyst, and the dispersant can be omitted.

[0068] According to a specific example, the silicone oil, the sustained-release material with a particle size of 100 mesh sieve-3000 mesh sieve and the silane coupling agent can be mixed evenly according to the above ratio, and ground to a particle size of less than or equal to 30 microns, and then the catalyst is added and the grinding is continued to a particle size of less than or equal to 20 microns, and then ultrasonically treated at room temperature (e.g., 22 ° C) for 0.5h-1h, so that the sustained-release particles can be obtained. Here, first mixing the silicone oil with the sustained-release material and then grinding it to a particle size of less than or equal to 30 microns can make the silicone oil and the sustained-release material mixed evenly, and thereafter, grinding it under the conditions of the catalyst to a particle size of less than or equal to 20 microns can make the silicone oil fully adsorbed and bonded to its exterior by the sustained-release material. However, when the particle size of the sustained-release material is less than 30 microns, the first grinding can be omitted, and optionally a stirring process can be provided, or the second grinding process can be directly performed. In addition, when the particle size of the sustained-release material is less than 15 microns, the second grinding process can be further omitted, and optionally a stirring process can be provided.

[0069] After the ceramic coating precursor and the slow-release particles are prepared, the slow-release particles can be mixed with the ceramic coating precursor to prepare a ceramic coating according to an exemplary embodiment.

[0070] According to an exemplary embodiment, during the preparation of the first ceramic coating, 61-92 parts by weight of a ceramic coating precursor and 5-30 parts by weight of slow-release particles may be mixed based on the total weight of the first ceramic coating (for example, the weight ratio of A, B, C, and slow-release particles D may be (20-30):(40-60):(1-2):(5-30)). After the ceramic coating precursor and the slow-release particles are mixed, the mixture may be stirred at 120-200 rpm for 6-8 hours to obtain the desired first ceramic coating.

[0071] Additionally, while the above method describes separately preparing a ceramic coating precursor and slow-release particles and then mixing them to obtain a ceramic coating, in a method combining the steps of preparing the ceramic coating precursor with preparing the slow-release particles, after mixing material B and material C, material A and the slow-release particles can be added simultaneously to the mixture. For example, 40-60 parts by weight of material B can be mixed with 1-2 parts by weight of material C, and the pH of the mixture can be adjusted to an acidic level (e.g., less than or equal to 4) due to the acidity of material C to obtain the first material. Material A and the slow-release particles can then be added to the mixture. The weight ratio of material A to material B can be in the range of (20-30):(40-60), and the amount of slow-release particles added can be in the range of 5.15 wt% to 32.97 wt% based on the total weight of the mixture of material A, material B, material C, and the slow-release particles. After mixing, the mixture can be stirred at a rotation speed of 120-200 rpm for 6-8 hours to obtain the desired first ceramic coating.

[0072] The method for preparing the first ceramic coating has been described above. When the first ceramic coating includes multiple sub-layers, corresponding sub-first ceramic coatings can be formed for each sub-layer using the aforementioned method for preparing the first ceramic coating. Each sub-first ceramic coating can differ only in the amount of slow-release particles added or the particle size of the slow-release particles. A person skilled in the art can readily derive the preparation methods for each sub-layer based on the preparation method for the first ceramic coating. Therefore, to avoid redundancy, a detailed description thereof will not be provided.

[0073] The second ceramic coating may be prepared before, during, or after the first ceramic coating is prepared.

[0074] According to an exemplary embodiment, the second ceramic coating may be a ceramic coating commonly used in the art, and thus, may be prepared using a conventional formula in the prior art.

[0075] According to the example, the second ceramic coating can be prepared by the following method: (1) silane and ethyl orthosilicate are mixed and stirred uniformly to obtain a silane composition of component E; (2) silica sol is mixed uniformly with isopropyl alcohol and deionized water, and an emulsifier and a thickener are added to obtain a slurry of component F; (3) formic acid, acetic acid, a buffer (e.g., boric acid) and a catalyst (e.g., zirconium acetate) are mixed uniformly to obtain a strong acid catalyst of component G; (4) the above three components are mixed in sequence according to a mass ratio of E:F:G=(20-30):(40-60):(1-2), and rolling and aging is performed to obtain the second ceramic coating, wherein the mixing order and aging method are as follows: first, components F and G are mixed uniformly according to the required parts, the pH is adjusted to below 4, rolling and dispersing for 0.5h, and then the required parts of E are added and shaken uniformly to obtain the required ceramic coating.

[0076] After the first ceramic coating and the second ceramic coating are prepared, the preparation of the first ceramic coating layer and the preparation of the second ceramic coating layer can be performed.

[0077] Preparation of the first ceramic coating and the second ceramic coating

[0078] After the ceramic coating is obtained, a first ceramic coating layer 200 may be formed on the substrate 100 using a layer forming process, and a second ceramic coating layer 300 may be formed on the first ceramic coating layer 200 .

[0079] For example, the first and second ceramic coatings can be applied using air spraying. The air spraying parameters for the first and second ceramic coatings are not limited, and the difference between the spraying of the first and second ceramic coatings may be simply that different spray times are used to form ceramic coatings of different thicknesses. The air spraying parameters are as follows: spraying distance 160 mm; air pressure 0.3 MPa; flow rate 8 L / min. However, the exemplary embodiment is not limited thereto; the air spraying parameters can be adjusted to suit the specific process, and those skilled in the art may also employ other layer formation methods to form a ceramic coating using the first and second ceramic coatings of the present invention. Furthermore, to enhance the bonding strength between the ceramic coating 200 and the substrate 100, the substrate may be treated. For example, the substrate may be sandblasted with 60# brown corundum to achieve a surface roughness of 3-6 microns. The substrate may then be cleaned and preheated to 40°C to 60°C before the ceramic coating formation process is performed.

[0080] After air spraying, the resultant may be cured at 230-280° C. for 10-15 minutes to form a first ceramic coating 200 with a thickness of 10-80 μm and a second ceramic coating 300 with a thickness of 8-20 μm.

[0081] As described above in detail in conjunction with the exemplary embodiments, the first ceramic coating of the present invention includes slow-release particles. Therefore, during cooking, the release of silicone oil can be slowed, thereby maintaining a long-lasting non-stick effect. Furthermore, since the ceramic coating of the present invention further includes a second ceramic coating, the sealing effect of the second ceramic coating can further slow the release of silicone oil.

[0082] Hereinafter, the beneficial effects of the inventive concept will be described with reference to specific examples.

[0083] Example 1

[0084] The first ceramic coating is formed by the following method.

[0085] S1: 80 wt% of methyltrimethoxysilane and 20 wt% of ethyl orthosilicate were mixed and stirred to obtain a silane composition of component A;

[0086] S2: 30 wt% of Akzo Nobel 1050 (silica sol), 8 wt% of titanium dioxide (pigment), 25 wt% of kaolin (filler), 3 wt% of Tween-80 (emulsifier), 1 wt% of water-based modified bentonite (thickener), 0.3 wt% of polyoxyethylene ether TRITONX-100 (wetting agent), 20 wt% of isopropyl alcohol and the balance of deionized water were mixed uniformly, and then added to a grinder and ground for 2 h to fully disperse and grind to a particle size of not more than 15 μm to obtain a component B slurry;

[0087] S3: 48 parts by weight of formic acid, 48 parts by weight of acetic acid, 1 part by weight of boric acid (buffer), and 0.5 parts by weight of zirconium acetate (catalyst) are uniformly mixed to obtain component C, a strongly acidic catalyst;

[0088] S4: 58 parts by weight of a hydroxy silicone oil with a molecular weight of 3000 and 42 parts by weight of vermiculite with a particle size of 100 to 3000 mesh (sustained-release material) are mixed, and then 3 parts by weight of a methoxysilane coupling agent are added and mixed evenly. The mixture is ground to a particle size of no more than 30 μm, and then 0.3 parts by weight of a titanate (catalyst) is added and the mixture is further ground to a particle size of no more than 20 μm. The mixture is then ultrasonically treated at room temperature of 22° C. for 0.5 h to obtain a sustained-release particle component D, wherein the particle size of the sustained-release particle component D obeys a normal distribution;

[0089] S5: The above four components are sequentially mixed in a weight ratio of A:B:C:D = 20:40:1:5, and tumble-cured to obtain the first ceramic coating. The mixing sequence and aging method are as follows: First, 40 parts by weight of component B and 1 part by weight of component C are mixed evenly, using component C to adjust the pH to 4. The mixture is then tumble-cured for 0.5 hours. Then, 20 parts by weight of component A is added and shaken evenly. Finally, 5 parts by weight of component D is added. The mixture is stirred at 200 rpm for 8 hours to obtain the desired first ceramic coating.

[0090] The second ceramic coating was formed by the following method.

[0091] W1: 80 wt% of methyltrimethoxysilane and 20 wt% of ethyl orthosilicate were mixed and stirred to obtain a silane composition of component E;

[0092] W2: 30 wt% of Akzo Nobel 1050 (silica sol), 3 wt% of Tween-80 (emulsifier), 1 wt% of water-based modified bentonite (thickener), 20 wt% of isopropyl alcohol, and the balance of deionized water were mixed to obtain component F slurry;

[0093] W3: 48 parts by weight of formic acid, 48 parts by weight of acetic acid, 1 part by weight of boric acid (buffer), and 0.5 parts by weight of zirconium acetate (catalyst) are uniformly mixed to obtain component G, a strongly acidic catalyst;

[0094] W4: The above three components are sequentially mixed in a weight ratio of E:F:G = 20:40:1, and tumble-cured to produce the second ceramic coating. The mixing sequence and aging method are as follows: First, evenly mix 40 parts by weight of component F and 1 part by weight of component G, adjusting the pH to 4 with component G. Roll-cured for 0.5 hours, then add 20 parts by weight of component E and shake until evenly mixed. This yields the desired second ceramic coating.

[0095] The non-stick cookware including the first ceramic coating and the second ceramic coating is manufactured by the following method using the first ceramic coating and the second ceramic coating.

[0096] B1: Substrate treatment: The stainless steel substrate is sandblasted with 60# brown corundum to form a surface roughness of 3 microns;

[0097] B2: Preheating. Clean the sandblasted substrate and preheat it to 60°C;

[0098] B3: Spraying. Using air spraying, a first ceramic coating with a thickness of 80 microns was formed on the substrate using the first ceramic coating. A second ceramic coating with a thickness of 8 microns was then formed on the first ceramic coating using the second ceramic coating. Air spraying parameters were as follows: spray distance 160 mm; air pressure 0.3 MPa; flow rate 8 L / min.

[0099] B4: Sintering: Curing at 250°C for 10 minutes.

[0100] By the above method, the non-stick cookware of Example 1 is obtained.

[0101] Example 2

[0102] The difference from Example 1 is that the sustained-release material is bentonite.

[0103] Example 3

[0104] The difference from Example 1 is that the sustained-release material is alpha alumina.

[0105] Example 4

[0106] The difference from Example 1 is that the particle size of the slow-release particles is less than or equal to 17 microns, and the particle size of the slow-release particle component D obeys a normal distribution.

[0107] Example 5

[0108] The difference from Example 1 is that the particle size of the slow-release particles is less than or equal to 12 microns, and the particle size of the slow-release particle component D obeys a normal distribution.

[0109] Example 6

[0110] The difference from Example 1 is that the particle size of the slow-release particles is less than or equal to 8 microns, and the particle size of the slow-release particle component D obeys a normal distribution.

[0111] Example 7

[0112] The difference from Example 1 is that the thickness of the first ceramic coating is 10 microns.

[0113] Example 8

[0114] The difference from Example 1 is that the thickness of the first ceramic coating is 30 microns.

[0115] Example 9

[0116] The difference from Example 1 is that the thickness of the first ceramic coating is 60 microns.

[0117] Example 10

[0118] The difference from Example 1 is that the thickness of the second ceramic coating is 13 microns.

[0119] Example 11

[0120] The difference from Example 1 is that the thickness of the second ceramic coating is 17 microns.

[0121] Example 12

[0122] The difference from Example 1 is that the thickness of the second ceramic coating is 20 microns.

[0123] Example 13

[0124] The difference from Example 1 is that A, B, C and D are mixed in sequence according to the weight ratio of A:B:C:D=20:40:1:12 to prepare the modified ceramic coating.

[0125] Example 14

[0126] The difference from Example 1 is that A, B, C and D are mixed in sequence according to the weight ratio of A:B:C:D=20:40:1:18 to prepare the modified ceramic coating.

[0127] Example 15

[0128] The difference from Example 1 is that A, B, C and D are mixed in sequence according to the weight ratio of A:B:C:D=20:40:1:29 to prepare the modified ceramic coating.

[0129] Example 16

[0130] The difference from Example 1 is that A, B, C and D are mixed in sequence according to the weight ratio of A:B:C:D=30:60:2:5 to prepare the modified ceramic coating.

[0131] Example 17

[0132] The difference from Example 1 is:

[0133] (1) preparing a first ceramic coating O1 by step S5;

[0134] (2) Also included is step S51, and the difference between step S51 and step S5 is that the components A, B, C, and D obtained in steps S1-S4 are sequentially mixed in a weight ratio of A:B:C:D=20:40:1:1 to prepare a sub-first ceramic coating 02;

[0135] (3) A first sub-layer having a thickness of 35 μm was formed on the substrate using the sub-first ceramic coating 02 by the air spraying method of Example 1, and a second sub-layer having a thickness of 45 μm was formed on the first sub-layer using the sub-first ceramic coating 01 by the air spraying method of Example 1.

[0136] Example 18

[0137] The difference from Example 1 is that the silicone oil consists of 20 wt % of hydroxy silicone oil with a molecular weight of 800, 60 wt % of hydroxy silicone oil with a molecular weight of 3000 and 20 wt % of hydroxy silicone oil with a molecular weight of 12000.

[0138] Example 19

[0139] The difference from Example 1 is that the silicone oil consists of 30 wt % of hydroxy silicone oil with a molecular weight of 800, 40 wt % of hydroxy silicone oil with a molecular weight of 3000 and 30 wt % of hydroxy silicone oil with a molecular weight of 12000.

[0140] Example 20

[0141] The difference from Example 1 is that the silicone oil consists of 25 wt % of hydroxy silicone oil with a molecular weight of 800, 50 wt % of hydroxy silicone oil with a molecular weight of 3000 and 25 wt % of hydroxy silicone oil with a molecular weight of 12000.

[0142] Example 21

[0143] The difference from Example 1 is that 35 parts by weight of hydroxy silicone oil with a molecular weight of 3000 is mixed with 42 parts by weight of sustained-release material.

[0144] Example 22

[0145] The difference from Example 1 is that 42 parts by weight of hydroxy silicone oil with a molecular weight of 3000 is mixed with 42 parts by weight of sustained-release material.

[0146] Example 23

[0147] The difference from Example 1 is that 58 parts by weight of hydroxy silicone oil with a molecular weight of 3000 is mixed with 49 parts by weight of sustained-release material.

[0148] Example 24

[0149] The difference from Example 1 is that 58 parts by weight of hydroxy silicone oil with a molecular weight of 3000 is mixed with 60 parts by weight of sustained-release material.

[0150] Comparative Example 1

[0151] The difference from Example 1 is that step S4 is omitted. That is, in step S5, components A, B, and C are mixed in order according to a weight ratio of A:B:C=22:40:1, and the resulting ceramic material precursor is used to manufacture non-stick cookware.

[0152] Comparative Example 2

[0153] The difference from Example 1 is that the second ceramic coating is not included.

[0154] Comparative Example 3

[0155] The difference from Example 1 is that 30 parts by weight of hydroxy silicone oil with a molecular weight of 3000 is mixed with 60 parts by weight of sustained-release material.

[0156] Comparative Example 4

[0157] The difference from Example 1 is that 60 parts by weight of hydroxy silicone oil with a molecular weight of 3000 is mixed with 40 parts by weight of sustained-release material.

[0158] The non-stick properties of the non-stick cookware of Examples 1-24 and Comparative Examples 1-4 were tested, and the test results are shown in the following table.

[0159] plan Long-lasting non-stickiness / times Example 1 13000 Example 2 11000 Example 3 12000 Example 4 12000 Example 5 11000 Example 6 8000 Example 7 9000 Example 8 12000 Example 9 13000 Example 10 14000 Example 11 16000 Example 12 17000 Example 13 21000 Example 14 22000 Example 15 25000 Example 16 9000 Example 17 13000 Example 18 18000 Example 19 19000 Example 20 22000 Example 21 12000 Example 22 14000 Example 23 11000 Example 24 15000 Comparative Example 1 500 Comparative Example 2 11000 Comparative Example 3 8000 Comparative Example 4 9000

[0160] Performance index test

[0161] The cookware obtained above was subjected to a performance test. The specific performance test method is as follows:

[0162] (1) Long-lasting non-stick test method: refer to 4.2.1 Fried egg non-stick test in GB_T 32095.2-2015. The unit is the number of times. The higher the number, the longer the life. The non-stick result is evaluated every 1000 times, and the number of times when the non-stickiness reaches level III is recorded.

[0163] (2) Plane wear resistance test method: GB_T 32095.2-2015 4.3.1 Plane wear resistance test, using 3M7447 scouring pad, applying a force of 15N, a frequency of 33 times / minute, and replacing the scouring pad every 500 times.

[0164] By comparing and analyzing Examples 1-24 of the present invention with Comparative Examples 1-4, it is not difficult to find that: the long-term non-stickiness of the existing conventional ceramic coating in Comparative Example 1 does not exceed 500 times; since Comparative Example 2 does not include a second ceramic coating, the long-term non-stickiness is relatively low; the silicone oil in Comparative Example 3 is not able to effectively provide a sustained-release effect due to its low content; in addition, the content of the sustained-release material in Comparative Example 4 is too low, and the amount of combined silicone oil is small, which cannot form an effective sustained-release effect; in comparison, the long-term non-stickiness of the inductive ceramic coating according to the present invention is 8,000-25,000 times.

[0165] Although one or more embodiments of the present invention have been described with reference to the drawings, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the claims.

Claims

1. A ceramic coating, characterized in that: The ceramic coating comprises: a first ceramic coating layer formed using a first ceramic coating, wherein the first ceramic coating comprises a ceramic coating precursor and slow-release particles dispersed in the ceramic coating precursor; and a second ceramic coating layer, located on the first ceramic coating layer as a sealing layer and formed using a second ceramic coating, Wherein, the sustained-release particles include a sustained-release material and silicone oil bound to the sustained-release material. The sustained-release material comprises at least one of vermiculite, zeolite, bentonite, diatomaceous earth, alpha alumina, silica aerogel, fumed silica, amorphous silica, hollow glass powder, porous silicate, layered silicate, porous phosphate, layered phosphate, porous carbonate, layered carbonate, porous sulfate and layered sulfate.

2. The ceramic coating according to claim 1, wherein The particle size of the sustained-release particles is less than or equal to 20 microns.

3. The ceramic coating according to claim 1, wherein The first ceramic coating has a thickness of 10 micrometers to 80 micrometers.

4. The ceramic coating according to claim 1, wherein The second ceramic coating has a thickness of 8-20 microns.

5. The ceramic coating according to claim 1, wherein The slow-release particles are contained in an amount of 5.15-32.97 parts by weight per 100 parts by weight of the first ceramic coating.

6. The ceramic coating according to claim 1, wherein By weight percentage, 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. Among them, the molecular weight of low molecular weight silicone oil is between 500-1000, the molecular weight of medium molecular weight silicone oil is between 3000-6000, and the molecular weight of high molecular weight silicone oil is between 12000-30000.

7. The ceramic coating according to claim 1, wherein The ceramic coating precursor and the second ceramic coating include the same material.

8. The ceramic coating according to claim 1, wherein The first ceramic coating includes at least a first sublayer and a second sublayer stacked on each other.

9. The ceramic coating according to claim 1, wherein The first sub-layer is below the second sub-layer, and the content of the sustained-release particles included in the first sub-layer is lower than the content of the sustained-release particles included in the second sub-layer.

10. A non-stick utensil, characterized in that: The non-stick utensil comprises a substrate and a ceramic coating according to any one of claims 1 to 9 disposed on the substrate.

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