Cookware and method of making same

Abstract

This application relates to the field of kitchenware, providing a kitchenware and its manufacturing method. The kitchenware includes a substrate and a first coating disposed on one side of the substrate. The first coating includes glass, and the open porosity of the first coating is ≤10%, the density is ≥90%, and the surface roughness Ra is ≤0.2μm. The kitchenware of this application, by using the first coating on the substrate, reduces the penetration, adhesion, and carbonization of oil stains into the interior of the kitchenware at high temperatures, reducing internal carbonization accumulation. Oil stains adhering to the surface can be removed by simple wiping or rinsing with water, maintaining easy-to-clean performance for a long time.

Description

Technical Field

[0001] This application relates to the field of kitchenware, and in particular to a kitchenware and a method for its preparation. Background Technology

[0002] During use, cooking oil, sauces, starches, sugars, and other organic substances in kitchenware undergo thermal decomposition and carbonization at high temperatures, forming stubborn, charred grease on the surface. How to ensure that the coating of kitchenware retains its easy-to-clean properties under high-temperature conditions has long been a technical challenge in this field. Summary of the Invention

[0003] In view of this, this application provides a kitchen utensil and a method for preparing the same, in order to solve the problem of difficult-to-clean coatings on kitchen utensil.

[0004] To solve the above-mentioned technical problems, the first aspect of this application provides a kitchen appliance, including a substrate and a first coating disposed on one side of the substrate. The first coating includes glass, and the open porosity of the first coating is ≤10%, the density is ≥90%, and the surface roughness Ra is ≤0.2μm.

[0005] According to one embodiment of this application, the open porosity of the first coating is ≤8%, and the density is ≥92%.

[0006] According to one embodiment of this application, the open porosity of the first coating is ≤5%, and the density is ≥95%.

[0007] According to one embodiment of this application, the open porosity of the first coating is ≤3%, and the density is ≥97%.

[0008] According to one embodiment of this application, the thickness of the first coating is 1 μm to 500 μm.

[0009] According to one embodiment of this application, the thickness of the first coating is 20 μm to 200 μm.

[0010] According to one embodiment of this application, the glass includes one or more of borosilicate glass, zinc phosphate glass, bismuth glass, aluminosilicate glass, and soda-lime-silicon glass; and / or the substrate includes one or more of stainless steel, carbon steel, aluminum alloy, cast iron, microcrystalline glass, and ceramics.

[0011] According to one embodiment of this application, the first coating further includes inorganic fillers, which include one or more of oxides, nitrides, and carbides; and / or, the first coating further includes inorganic pigments, which include one or more of metal oxide pigments, mixed oxide pigments, silicate pigments, phosphate pigments, and borate pigments; wherein, the metal oxide pigments include one or more of cobalt oxide, copper oxide, chromium oxide, iron oxide, or titanium dioxide; and the mixed oxide pigments include cobalt black pigment, iron chromium black pigment, cobalt aluminum blue pigment, iron chromium brown pigment, zinc iron brown pigment, and manganese zinc iron black pigment. The first coating may contain one or more of the following pigments: silicate pigments include one or more of vanadium zirconium silicate yellow pigment, iron zirconium silicate pink pigment, chromium zirconium silicate green pigment, and manganese silicate violet pigment; phosphate pigments include one or more of manganese phosphate violet pigment, iron phosphate brown pigment, cobalt phosphate blue pigment, and zinc phosphate pigment; borate pigments include one or more of copper borate blue pigment, copper borate green pigment, cobalt borate blue pigment, and manganese borate violet pigment; and / or, the first coating may further contain an adhesive, which may contain one or more of cobalt oxide, nickel oxide, copper oxide, manganese oxide, and molybdenum trioxide.

[0012] According to one embodiment of this application, the inorganic filler includes one or more of nano-silica, alumina, zirconium oxide, titanium oxide, cerium oxide, zinc oxide, iron oxide, silicon carbide, silicon nitride, boron nitride, and clay.

[0013] According to one embodiment of this application, the kitchenware further includes a second coating, which is disposed between the substrate and the first coating. The second coating includes one or more of the following: a silica sol layer, a silicate layer, a phosphate layer, a borate layer, an aluminum sol layer, a titanium sol layer, a zirconium sol layer, an oxide layer, a nitride layer, a carbide layer, and an enamel layer. The oxide layer includes at least one of aluminum oxide, zirconium oxide, silicon dioxide, and titanium dioxide; the nitride layer includes at least one of silicon nitride, aluminum nitride, and titanium nitride; and the carbide layer includes at least one of silicon carbide, titanium carbide, and chromium carbide. The thickness of the second coating is 0.01 μm to 500 μm.

[0014] According to one embodiment of this application, the thickness of the second coating is 0.1 μm to 250 μm.

[0015] According to one embodiment of this application, the thickness of the second coating is 20 μm to 200 μm.

[0016] This application provides a method for preparing kitchenware, comprising: providing a substrate; coating a first coating on the surface of the substrate; curing the first coating at a first preset temperature to form a first coating layer; wherein the first coating comprises glass powder, and the softening temperature of the glass powder is 300℃~800℃.

[0017] According to one embodiment of this application, the glass powder has at least one of the following characteristics: (1) The softening temperature of the glass powder is 400℃~650℃. (2) The glass powder includes one or more of borosilicate glass powder, zinc phosphate glass powder, bismuth glass powder, aluminosilicate glass powder, and sodium-calcium-silicon glass powder. (3) The particle size of the glass powder is 0.01μm~100μm. (4) The particle size of the glass powder is 1μm~20μm. (5) The particle size distribution of the glass powder is unimodal or multimodal; when the particle size of the glass powder is multimodal, the glass powder includes a first particle and a second particle, and the particle size ratio of the first particle and the second particle is (2~10):1; the particle size of the first particle is greater than or equal to 10μm and less than or equal to 20μm, and the particle size of the second particle is greater than or equal to 1 micrometer and less than or equal to 10 micrometers.

[0018] According to one embodiment of this application, the first coating further includes a diluent and a dispersant; wherein, based on the total mass of the first coating, the mass percentage of glass powder is 30% to 80%, the mass percentage of diluent is 15% to 65%, and the mass percentage of dispersant is 0.5% to 5%.

[0019] According to one embodiment of this application, the diluent includes one or more of water, alcohol solvents, ketone solvents, ester solvents, and ether solvents; wherein the alcohol solvent includes one or more of methanol, ethanol, isopropanol, and n-butanol; the ketone solvent includes one or more of acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; the ester solvent includes one or more of ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and propylene glycol monopropyl ether acetate; the ether solvent includes one or more of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether; the water includes one or two of deionized water and pure water; and the dispersant includes one or more of polycarboxylates, ammonium polyacrylates, sodium polyacrylates, polyethylene glycol, polyvinyl alcohol, and polyvinylpyrrolidone.

[0020] According to one embodiment of this application, the first coating further includes inorganic fillers, with the inorganic fillers accounting for 1% to 5% of the total mass of the first coating; and / or, the first coating further includes inorganic pigments, with the inorganic pigments accounting for 1% to 5% of the total mass of the first coating; and / or, the first coating further includes an adhesive, with the adhesive accounting for 0.05% to 5% of the total mass of the first coating.

[0021] According to one embodiment of this application, the first preset temperature is 300°C to 900°C.

[0022] According to one embodiment of this application, the first preset temperature is 300°C to 700°C.

[0023] According to one embodiment of this application, the first preset temperature is 350℃~600℃.

[0024] The beneficial effects of this application are as follows: This application provides a kitchen utensil and a method for preparing the same. The kitchen utensil includes a substrate and a first coating disposed on one side of the substrate. The first coating includes glass, and the open porosity of the first coating is ≤10%, the density is ≥90%, and the surface roughness Ra is ≤0.2μm. By using the first coating on the substrate, the kitchen utensil of this application reduces the penetration and carbonization of oil stains into the interior of the kitchen utensil at high temperatures, reducing internal carbonization accumulation. Oil stains adhering to the surface can be removed by simple wiping or rinsing with water, maintaining easy-to-clean performance for a long time. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them: Figure 1 This is a schematic diagram of the membrane layer of a kitchen utensil provided in an embodiment of this application.

[0026] Figure 2 This is a schematic diagram of the membrane layer of another kitchen appliance provided in an embodiment of this application. Detailed Implementation

[0027] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not all structures. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0028] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0029] In Chinese cooking, the surface temperature of kitchen utensils often reaches 250℃~300℃, and in some areas even exceeds 350℃. Under such high-temperature conditions, organic matter such as cooking oil and sauces are prone to thermal decomposition and carbonization, forming stubborn charred grease. Therefore, how to maintain the easy-to-clean properties of kitchen utensil coatings under high-temperature conditions has been a long-standing technical challenge in this field.

[0030] Current kitchenware coatings have significant limitations: organic resin coatings, such as Teflon and silicone, while exhibiting excellent non-stick properties at room or medium temperatures, decompose and carbonize over long-term use at temperatures above 260°C, leading to coating failure and failing to meet the high-temperature cooking requirements of Chinese stir-frying and dry-heating. Traditional kitchen enamel can withstand temperatures above 500°C, but after high-temperature sintering, it has numerous micropores and a rough surface. At high temperatures, complex stains can penetrate into the pores under capillary forces and adhere to the rough surface through van der Waals forces. After continuous high-temperature carbonization, these stains firmly bond with the coating, accumulating with each use and losing their easy-to-clean properties. Regular cleaning is insufficient to remove them, which is the core pain point in their application.

[0031] For a long time, the technical bottleneck in this field has been that organic coatings are dense but not resistant to high temperatures; inorganic enamel coatings are resistant to high temperatures but cannot achieve complete density and smoothness, making it difficult to solve the problem of oil penetration and adhesion. How to simultaneously achieve high-temperature stability and dense, anti-penetration and anti-adhesion properties in a pure inorganic system, thereby obtaining durable high-temperature easy-to-clean performance, has been a long-standing technical gap in the industry.

[0032] In view of this, this application provides a kitchen utensil 10 and its preparation method, achieving a technological breakthrough in maintaining easy-to-clean performance for a long time under high temperature conditions above 300℃.

[0033] Reference Figure 1 , Figure 1 This is a schematic diagram of the film layer of a kitchen appliance provided in an embodiment of this application. The kitchen appliance 10 includes a substrate 101 and a first coating 102 disposed on one side of the substrate 101. The first coating 102 includes glass, and the open porosity of the first coating 102 is ≤10%, the density is ≥90%, and the surface roughness Ra is ≤0.2μm.

[0034] The kitchenware 10 of this embodiment has a first coating 102 located on one side of the substrate 101. The first coating 102 has an open porosity ≤10%, a density ≥90%, and a surface roughness Ra ≤0.2μm. These three properties work synergistically to ensure that the first coating 102 maintains its long-lasting, easy-to-clean properties of preventing penetration and adhesion during long-term use at 300℃~400℃. Specifically: the low open porosity reduces micropores, reducing the penetration and carbonization of oil stains into the first coating 102; the high density makes the first coating 102 structurally compact, further enhancing its anti-penetration ability; and the low surface roughness reduces the physical adhesion sites of oil stains, so that even if the oil stains adhering to the surface carbonize at high temperatures, they remain as a loose, thin layer with weak adhesion to the first coating 102, and can be removed simply by wiping or rinsing with water. The interaction of these three properties ensures that the kitchenware 10 does not decompose, pulverize, or loosen its structure during long-term use at 300℃~400℃, thus improving the durability of its anti-penetration and anti-adhesion functions.

[0035] The open porosity of the first coating 102 can be 10%, 9.5%, 9%, 8%, 6.5%, 5%, 4.5%, 4%, 3%, 2%, 1%, etc., or a range of any two of the above values, for example, 1%~5%, 5%~8%, 8%~10%, 4%~9%, etc.

[0036] The density of the first coating 102 can be 90%, 92%, 93.5%, 94%, 95%, 96%, 98%, 99%, 99.5%, or a range of any two of the above values, such as 90%~95%, 95%~98%, 98%~99.5%, etc.

[0037] The surface roughness of the first coating 102 can be 0.2μm, 0.18μm, 0.17μm, 0.15μm, 0.12μm, 0.1μm, 0.08μm, 0.05μm, 0.03μm, etc., or a range of any two of the above values, for example, 0.03μm~0.1μm, 0.1μm~0.15μm, 0.15μm~0.2μm, 0.08μm~0.12μm, 0.1μm~0.17μm, etc.

[0038] According to one embodiment of this application, the first coating 102 has an open porosity of ≤8% and a density of ≥92%.

[0039] In this embodiment, the porosity and density of the first coating 102 are within the aforementioned range, which can reduce the penetration, adhesion, and carbonization of oil stains into the interior of the kitchenware 10 at high temperatures, thereby reducing internal carbonization accumulation. Even if surface-adhered oil stains are carbonized at high temperatures, they remain in a loose, thin layer with weak adhesion to the first coating 102, and can be removed by simple wiping or rinsing with water, thus maintaining easy-to-clean properties for a long time.

[0040] The open porosity of the first coating 102 can be 8%, 7%, 6.5%, 5%, 4.5%, 4%, 3%, 2%, 1%, etc., or a range of any two of the above values, for example, 1%~4%, 4%~6.5%, 6.5%~8%, etc.

[0041] The density of the first coating 102 can be 92%, 93.5%, 94.5%, 95%, 96%, 98%, 99%, 99.5%, or a range of any two of the above values, such as 92%~95%, 95%~98%, 98%~99.5%.

[0042] According to one embodiment of this application, the first coating 102 has an open porosity of ≤5% and a density of ≥95%.

[0043] In this embodiment of the application, the porosity and density of the first coating 102 are within the above-mentioned range, which can reduce the penetration, adhesion and carbonization of oil stains into the interior of the kitchenware 10 at high temperatures, reduce internal carbonization accumulation, and maintain easy-to-clean performance for a long time.

[0044] The open porosity of the first coating 102 can be 5%, 4.5%, 4%, 3%, 2%, 2.5%, 1.5%, 1%, 0.5%, 0.2%, etc., or a range of any two of the above values, for example, 0.2%~0.5%, 0.5%~1.5%, 1.5%~2.5%, 2.5%~4%, 4%~5%, 1%~3%, etc.

[0045] The density of the first coating 102 can be 95%, 96%, 98%, 99%, 99.5%, 99.8%, or a range of any two of the above values, such as 95%~98%, 98%~99%, 99%~99.8%.

[0046] According to one embodiment of this application, the open porosity of the first coating 102 is ≤3%, and the density is ≥97%.

[0047] In this embodiment, the open porosity and density of the first coating 102 are within the aforementioned ranges, ensuring that even if there are minor scratches or defects on the surface of the first coating 102, oil stains cannot penetrate into the interior of the first coating 102 through continuous pores, thereby improving its long-lasting anti-fouling performance at high temperatures. Because the open porosity of the first coating 102 is ≤3% and the pores are not interconnected, the capillary penetration channels are cut off, and oil stains can only remain on the coating surface, which can be removed by simple wiping or rinsing with water, thus maintaining its easy-to-clean performance for a long time.

[0048] The open porosity of the first coating 102 can be 3%, 2%, 2.5%, 1.5%, 1%, 0.5%, 0.2%, etc., or a range of any two of the above values, for example, 0.2%~0.5%, 0.5%~1.5%, 1.5%~2.5%, 2.5%~3%, 1%~3%, etc.

[0049] The density of the first coating 102 can be 97%, 98%, 99%, 99.5%, 99.8%, or a range of any two of the above values, such as 97%~98%, 98%~99%, 99%~99.8%, 97%~99%, etc.

[0050] According to one embodiment of this application, the thickness of the first coating 102 is 1 μm to 500 μm.

[0051] In this embodiment, the thickness of the first coating 102 is not less than 1 μm, ensuring its continuity and integrity. This avoids local defects or penetration due to excessive thinness, fully leveraging its advantages of low open porosity and high density. At high temperatures, it forms a dense protective layer, inhibiting the penetration, adhesion, and carbonization of oil stains into the substrate 101. Simultaneously, a thickness not exceeding 500 μm reduces the risk of decreased adhesion, thermal stress cracking, or excessive cost caused by an excessively thick first coating 102, while maintaining good thermal conductivity of the kitchenware 10. Therefore, with the thickness of the first coating 102 within the aforementioned range, it can maintain a smooth surface and structural stability for a prolonged period at temperatures above 300°C, ensuring that oil stains adhere to the surface only in a loose, thin layer, making them easy to remove by wiping or rinsing with water, achieving durable and easy-to-clean performance.

[0052] The thickness of the first coating 102 can be 1μm, 5μm, 30μm, 50μm, 100μm, 180μm, 250μm, 310μm, 400μm, 450μm, 500μm, etc., or a range of any two of the above values, for example, it can be 1μm~5μm, 5μm~180μm, 180μm~310μm, 310μm~500μm, 100μm~250μm, 30μm~450μm, etc.

[0053] According to one embodiment of this application, the thickness of the first coating 102 is 20 μm to 200 μm.

[0054] In this embodiment, the thickness of the first coating 102 is within the aforementioned range, allowing it to form a continuous, complete, and structurally stable barrier. This more effectively covers the microscopic undulations of the substrate 101 surface, effectively optimizing local weak points or pinholes, thereby achieving its inherent low open porosity and high density characteristics. At high temperatures, it can more reliably block the capillary penetration path of oil stains. Simultaneously, the thickness of the first coating 102 does not exceed 200 μm, effectively reducing the risk of excessive internal stress during thermal cycling due to the difference in thermal expansion coefficients between the thicker first coating 102 and the substrate 101, which could lead to cracking or peeling. It also improves efficient heat conduction, reducing the impact on cooking efficiency. Controlling the thickness of the first coating 102 within the aforementioned range ensures excellent protective performance while maintaining good adhesion, thermal shock resistance, and overall thermal conductivity of the cookware 10. This also helps control production costs, maintains its dense and smooth structure over the long term, and ensures that oil stains and carbon deposits are only loosely attached to the surface, making them easy to remove. This results in a stable and long-lasting function of easy cleaning at high temperatures.

[0055] The thickness of the first coating 102 can be 20μm, 50μm, 85μm, 100μm, 120μm, 150μm, 175μm, 185μm, 200μm, etc., or a range of any two of the above values, for example, it can be 20μm~85μm, 85μm~150μm, 150μm~185μm, 185μm~200μm, 50μm~175μm, 120μm~200μm, etc.

[0056] According to one embodiment of this application, the glass includes one or more of borosilicate glass, zinc phosphate glass, bismuth glass, aluminosilicate glass, and soda-lime-silicon glass; and / or the substrate 101 includes one or more of stainless steel, carbon steel, aluminum alloy, cast iron, microcrystalline glass, and ceramics.

[0057] In this embodiment, the glass comprising the first coating 102 is selected from the aforementioned inorganic materials and possesses high-temperature stability. Under long-term use conditions of 300°C to 400°C, it will not decompose, pulverize, or loosen its structure, fundamentally overcoming the bottleneck of high-temperature coating failure. Simultaneously, by selecting and blending glasses with different compositions, the thermal expansion coefficient, melt viscosity, chemical durability, and compatibility with the substrate 101 of the first coating 102 can be flexibly adjusted. This provides reliable raw materials for achieving the aforementioned low porosity and high density densification sintering, ultimately enhancing the long-term anti-permeability and anti-adhesion capabilities of the first coating 102 at high temperatures.

[0058] The substrate 101 of the kitchenware 10 is made of the above-mentioned material, which is well bonded with the first coating 102. Without changing the substrate structure and mechanical properties of the traditional kitchenware 10, the high-temperature easy-to-clean coating technology can be seamlessly applied to various types of kitchenware 10, and can be mass-produced and promoted.

[0059] According to one embodiment of this application, the first coating 102 further includes inorganic fillers, which include one or more of oxides, nitrides, and carbides; and / or, the first coating 102 further includes inorganic pigments, which include one or more of metal oxide pigments, mixed oxide pigments, silicate pigments, phosphate pigments, and borate pigments; wherein, the metal oxide pigments include one or more of cobalt oxide, copper oxide, chromium oxide, iron oxide, or titanium dioxide; and the mixed oxide pigments include one or more of cobalt aluminum blue pigment, iron chromium brown pigment, zinc iron brown pigment, and manganese zinc iron black pigment. One or more types; silicate pigments include one or more of vanadium zirconium silicate yellow pigment, iron zirconium silicate pink pigment, chromium zirconium silicate green pigment, and manganese silicate violet pigment; phosphate pigments include one or more of manganese phosphate violet pigment, iron phosphate brown pigment, cobalt phosphate blue pigment, and zinc phosphate pigment; borate pigments include one or more of copper borate blue pigment, copper borate green pigment, cobalt borate blue pigment, and manganese borate violet pigment; and / or, the first coating 102 further includes an adhesive, the adhesive including one or more of cobalt oxide, nickel oxide, copper oxide, manganese oxide, and molybdenum trioxide.

[0060] In this embodiment, the first coating 102 further includes inorganic fillers selected from the aforementioned materials. These inorganic fillers can effectively improve the mechanical strength, wear resistance, acid and alkali resistance, and scratch resistance of the first coating 102, thereby extending its service life. Simultaneously, the introduction of inorganic fillers can also adjust the coefficient of thermal expansion of the first coating 102, allowing it to better match the substrate 101, reducing thermal stress caused by thermal cycling, and thus improving the thermal shock resistance and bonding strength of the first coating 102.

[0061] The first coating 102 also includes inorganic pigments selected from the above-mentioned materials. These inorganic pigments can be used to prepare colored coatings with decorative effects. Furthermore, the inorganic pigments themselves have excellent high-temperature stability and chemical inertness. They will not decompose or change color under long-term high-temperature cooking conditions, and can maintain the aesthetics of the kitchenware 10 for a long time.

[0062] The first coating 102 also includes an adhesive agent selected from the above-mentioned materials, which can enhance the adhesion between the first coating 102 and its underlying interface material (e.g., substrate 101), improve the bonding strength and bonding durability between the two, and make the first coating 102 less prone to peeling or flaking under long-term high-temperature use, thermal shock and physical friction.

[0063] According to one embodiment of this application, the inorganic filler includes one or more of nano-silica, alumina, zirconium oxide, titanium oxide, cerium oxide, zinc oxide, iron oxide, silicon carbide, silicon nitride, and boron nitride.

[0064] In this embodiment, the inorganic filler is selected from the above-mentioned materials, which can effectively improve the mechanical strength, wear resistance, acid and alkali resistance, and scratch resistance of the first coating 102, and extend its service life. At the same time, the introduction of inorganic filler can also adjust the coefficient of thermal expansion of the first coating 102, so as to better match it with the substrate 101, reduce the thermal stress generated by thermal cycling, and thus improve the thermal shock resistance and bonding strength of the first coating 102.

[0065] Among them, nano-silica, as a nanoscale filler, can effectively fill the micro-voids in the glass matrix, reduce the open porosity of the first coating 102, and increase its density, thereby strengthening its barrier function of impermeability and anti-adhesion.

[0066] Cerium oxide not only fills micropores, but also has a certain high-temperature stability and sintering promotion effect, which helps to form a denser, smoother and more uniform coating structure during the preparation process.

[0067] Alumina and zirconium oxide have high hardness, and as reinforcing phases, they can improve the wear resistance, scratch resistance and overall mechanical strength of the first coating 102, effectively resisting daily scratches from kitchen utensils such as spatulas 10.

[0068] Silicon carbide and silicon nitride have high hardness and high strength, enhancing wear resistance and toughness, making them particularly suitable for applications requiring high wear resistance.

[0069] Titanium oxide (titanium dioxide) is not only a hardening filler, but may also have certain photocatalytic self-cleaning potential, which helps to decompose organic stains on the surface.

[0070] In addition to enhancing the wear resistance, scratch resistance and overall mechanical strength of the first coating 102, zinc oxide also contributes certain antibacterial and stabilizing properties.

[0071] Iron oxide also enhances the wear resistance, scratch resistance and overall mechanical strength of the first coating 102.

[0072] Boron nitride has high-temperature lubricity, which can reduce the coefficient of friction on the surface of the first coating 102, further improving its non-stick and easy-clean properties. At the same time, its high thermal conductivity helps to improve local heat distribution.

[0073] According to one embodiment of this application, referring to Figure 2 , Figure 2This is a schematic diagram of the film layer of another kitchen appliance provided in an embodiment of this application. The kitchen appliance 10 also includes a second coating layer 103, which is disposed between the substrate 101 and the first coating layer 102. The second coating layer 103 includes one or more of the following: a silica sol layer, a silicate layer, a phosphate layer, a borate layer, an aluminum sol layer, a titanium sol layer, a zirconium sol layer, an oxide layer, a nitride layer, a carbide layer, and an enamel layer; the thickness of the second coating layer 103 is 0.01 μm to 500 μm.

[0074] In this embodiment, the kitchen appliance 10 has a multi-layer structure, and further includes a second coating 103. The second coating 103 is selected from the aforementioned materials and serves as an intermediate transition layer between the substrate 101 and the first coating 102. It can effectively wet and anchor to the surface of the substrate 101 through physical penetration or chemical reaction, while providing a good bonding interface for the first coating 102. This enhances the adhesion and bonding durability between the first coating 102 and the substrate 101, reducing the possibility of delamination or peeling under high temperature or thermal shock. By selecting a material with a coefficient of thermal expansion compatible with the substrate 101 and the first coating 102 (such as a specific oxide layer or enamel layer), the second coating 103 can buffer or disperse thermal stress caused by temperature changes, reducing the risk of internal cracking of the first coating 102 and improving overall thermal shock resistance. Furthermore, the second coating 103 can fill the micropores, scratches or unevenness on the surface of the substrate 101 to form a dense, smooth and uniform transition surface. This not only blocks the influence of impurities or defects that may exist in the substrate 101 on the first coating 102, but also provides a smoother and more complete deposition substrate for the first coating 102, which helps the first coating 102 achieve its low open porosity and high density structure.

[0075] The thickness of the second coating 103 ranges from 0.01 μm to 500 μm, allowing for flexible adjustment based on the type of substrate 101, process requirements, and performance needs. This ensures the aforementioned functions while also achieving a thinner and more efficient coating system. The thickness of the second coating 103 can be 0.01 μm, 2 μm, 10 μm, 50 μm, 100 μm, 200 μm, 380 μm, 450 μm, 500 μm, or any range of two of the above values. For example, it can be 0.01 μm~100 μm, 100 μm~380 μm, 380 μm~500 μm, 50 μm~450 μm, 100 μm~500 μm, etc.

[0076] According to one embodiment of this application, the thickness of the second coating 103 is 0.1 μm to 250 μm.

[0077] In this embodiment, the thickness of the second coating 103 is within the aforementioned range, enabling the second coating 103 to continuously and completely cover the surface of the substrate 101, effectively fulfilling its fundamental functions of enhancing adhesion, sealing microscopic defects in the substrate 101, and buffering thermal stress. Simultaneously, it effectively reduces problems such as internal stress accumulation, decreased adhesion, reduced heat transfer efficiency, and increased costs that may be caused by an excessively thick intermediate layer.

[0078] The thickness of the second coating 103 can be 0.1μm, 1μm, 5μm, 50μm, 80μm, 120μm, 200μm, 250μm, etc., or a range of any two of the above values, for example, it can be 0.1μm~50μm, 50μm~200μm, 200μm~250μm, 120μm~200μm, etc.

[0079] According to one embodiment of this application, the thickness of the second coating 103 is 20 μm to 200 μm.

[0080] In this embodiment, the thickness of the second coating 103 is within the aforementioned range, allowing it to fully wet and cover the microstructure of the substrate 101 surface. This effectively fulfills its core functions of enhancing adhesion, sealing pores, and buffering stress, avoiding local defects or functional incompleteness caused by excessive thinness. Simultaneously, a thickness not exceeding 200 μm reduces the risk of significantly increased internal stress, excessive thermal resistance affecting heat transfer efficiency, and weakened bonding between the second coating and the substrate 101 or the first coating 102 due to thermal expansion mismatch, which could result from an excessively thick intermediate layer. This range is within the range that is easily and precisely controlled by conventional coating preparation processes (such as spraying and dip coating), which is beneficial for obtaining coatings with uniform thickness and consistent performance, thereby improving production yield and offering good cost-effectiveness.

[0081] The thickness of the second coating 103 can be 20μm, 40μm, 80μm, 120μm, 150μm, 180μm, 200μm, etc., or a range of any two of the above values, for example, it can be 20μm~80μm, 80μm~150μm, 150μm~200μm, 40μm~120μm, etc.

[0082] This application provides a method for preparing a kitchen utensil 10, comprising: providing a substrate 101; coating the surface of the substrate 101 with a first coating material; and curing the first coating material at a first preset temperature to form a first coating layer 102; wherein the first coating material comprises glass powder, and the softening temperature of the glass powder is 300℃~800℃.

[0083] In this embodiment of the application, the glass powder selected in the softening temperature range mentioned above is the key to achieving low-temperature densification, so that the glass phase can be fully melted under the subsequent first preset temperature condition and transformed into a glass melt with low viscosity and good fluidity, so as to fully fill the gaps between particles and reduce pores.

[0084] The softening temperature of the glass powder can be 300℃, 320℃, 335℃, 350℃, 365℃, 380℃, 390℃, 400℃, 420℃, 435℃, 450℃, 462℃, 475℃, 498℃, 510℃, 550℃, 580℃, 600℃, 625℃, 633℃, 658℃, 666℃, 678℃, 688℃, 700℃, 715℃, 735℃, 756℃, 780℃, 795℃, 800℃, etc., or a range of any two of the above values, for example, 300℃~450℃, 450℃~600℃, 600℃~800℃, 400℃~700℃, etc.

[0085] In some embodiments, the first preset temperature is 300℃~900℃; in some embodiments, the first preset temperature is 300℃~700℃; in some embodiments, the first preset temperature is more preferably 350℃~600℃.

[0086] Sintering at a first preset temperature ensures that the low-softening-temperature glass powder melts completely and flows well, while avoiding excessively high temperatures that could lead to glass component volatilization, abnormal grain growth, or adverse reactions with the substrate 101. At this first preset temperature, the molten glass, due to its low viscosity, spreads rapidly and self-levels, significantly reducing micropores, pinholes, and micro-pits. This minimizes the chance of oil, sauces, protein residues, etc., entering the coating or mechanically embedding into the surface. Under these conditions, the molten glass fully wets and fills the micro-voids between particles, allowing the first coating 102 to become denser during curing, resulting in low open porosity and fundamentally eliminating continuous capillary channels through which oil can penetrate and adhere.

[0087] Thanks to the highly dense, smooth, and low-roughness surface obtained at the first preset temperature, the first coating 102 of this application effectively prevents stains from firmly adhering to the coating surface and deeply carbonizing during actual use. The contaminants remain on the coating surface in a loose, poorly continuous thin layer, easily removed by rinsing with water or simple wiping. Even after repeated high-temperature heating cycles, it maintains good cleanability. Compared to traditional high-softening-point glass powder systems that require higher firing temperatures to achieve similar density and smoothness, this application can produce a smoother surface at a lower firing temperature, improving both stain resistance and cleanability while reducing energy consumption and the risk of oxidation and deformation of the metal substrate.

[0088] The first preset temperature can be 300℃, 320℃, 335℃, 350℃, 355℃, 385℃, 398℃, 410℃, 430℃, 445℃, 460℃, 472℃, 485℃, 498℃, 520℃, 560℃, 590℃, 610℃, 635℃, 643℃, 668℃, 676℃, 688℃, 698℃, 710℃, 725℃, 745℃, 766℃, 790℃, 795℃, 800℃, etc., or a range consisting of any two of the above values, for example, it can be 300℃~460℃, 460℃~610℃, 610℃~800℃, 410℃~710℃, etc.

[0089] According to one embodiment of this application, the glass powder has at least one of the following characteristics: (1) The softening temperature of the glass powder is 400℃~650℃. (2) The glass powder includes one or more of borosilicate glass powder, zinc phosphate glass powder, bismuth glass powder, aluminosilicate glass powder, and sodium-calcium-silicon glass powder. (3) The particle size of the glass powder is 0.01μm~100μm. (4) The particle size of the glass powder is 1μm~20μm. (5) The particle size distribution of the glass powder is unimodal or multimodal; when the particle size of the glass powder is multimodal, the glass powder includes a first particle and a second particle, and the particle size ratio of the first particle and the second particle is (2~10):1; the particle size of the first particle is greater than or equal to 10μm and less than or equal to 20μm, and the particle size of the second particle is greater than or equal to 1 micrometer and less than or equal to 10 micrometers.

[0090] In this embodiment, the softening temperature range of the glass powder is 400℃~650℃, allowing the glass powder to fully melt and form a melt with good fluidity, efficiently filling pores and achieving high density of the first coating 102. The softening temperature of the glass powder can be 400℃, 412℃, 425℃, 435℃, 440℃, 450℃, 465℃, 478℃, 495℃, 498℃, 500℃, 510℃, 525℃, 533℃, 545℃, 550℃, 560℃, 575℃, 586℃, 592℃, 600℃, 620℃, 635℃, 645℃, 650℃, etc., or a range composed of any two of the above values, for example, 400℃~550℃, 550℃~650℃, 500℃~600℃, 450℃~650℃, etc.

[0091] The glass powder is selected from the above materials and has good chemical stability and a coefficient of thermal expansion that matches the substrate 101, so that a first coating 102 with density, adhesion and durability can be obtained.

[0092] When the particle size of the glass powder is controlled within the above range (0.01μm~100μm or 1μm~20μm), it can achieve a relatively close packing and has a suitable specific surface area and melting rate during sintering, which is beneficial to the formation of a uniform and dense glass phase.

[0093] The particle size of the glass powder can be 0.01μm, 0.05μm, 1μm, 20μm, 30μm, 50μm, 70μm, 80μm, 100μm, etc., or any range of two of the above values, for example, 0.01μm~20μm, 20μm~70μm, 70μm~100μm, 1μm~50μm, 30μm~80μm, etc.

[0094] The particle size of the glass powder can be 1μm, 5μm, 10μm, 12μm, 15μm, 18μm, 20μm, etc., or any range of two of the above values, such as 1μm~10μm, 10μm~15μm, 15μm~20μm, 5μm~18μm, etc.

[0095] The particle size distribution of glass powder can be either unimodal or multimodal.

[0096] Single-peak distribution is suitable for simplified processes where particle size concentration is required.

[0097] The multi-peak distributed glass powder includes first particles and second particles. The first particles (10μm~20μm) form a stacked skeleton, while the second particles (1μm~10μm) fill the gaps between the first particles, achieving close stacking before sintering. This reduces the open porosity of the first coating 102, allowing the subsequent glass melt to fill fewer and smaller residual gaps, thereby increasing the final density and reducing the open porosity.

[0098] The particle size of the first particle can be 10μm, 12μm, 15μm, 17μm, 18μm, 20μm, etc., or a range of any two of the above values, for example, 10μm~15μm, 15μm~20μm, 12μm~17μm, etc.

[0099] The particle size of the second particle can be 1μm, 3μm, 5μm, 7μm, 8μm, 9.5μm, 10μm, or any range of two of the above values, such as 1μm~5μm, 5μm~8μm, 8μm~9.5μm, 3μm~10μm, etc.

[0100] According to one embodiment of this application, the first coating further includes a diluent and a dispersant; wherein, based on the total mass of the first coating, the mass percentage of glass powder is 30% to 80%, the mass percentage of diluent is 15% to 65%, and the mass percentage of dispersant is 0.5% to 5%.

[0101] In this embodiment, glass powder serves as the core functional phase in the first coating 102, providing high-temperature stability and densification capabilities. Its mass percentage falls within the aforementioned range, enabling the first coating 102 to form a continuous and complete glass matrix after curing, providing high density. Simultaneously, it reduces the impact on coating uniformity and layer thickness control caused by excessively high solid content, which could lead to excessive viscosity and poor flowability in the first coating. Based on the total mass of the first coating, the mass percentage of glass powder can be 30%, 35%, 40%, 50%, 68%, 75%, 80%, or any range of two of the aforementioned values, such as 30%~50%, 50%~80%, 35%~68%, 40%~75%, etc.

[0102] The thinner is used to adjust the viscosity and flowability of the first coating, making it suitable for specific coating processes such as spraying, dipping, and spin coating, so as to form a uniform wet film on the substrate 101. Within the aforementioned mass ratio, the thinner maintains good workability while reducing problems such as solid particle settling or cracking after drying. The thinner completely volatilizes and decomposes during the sintering process. Based on the total mass of the first coating, the mass ratio of the thinner can be 15%, 25%, 30%, 40%, 50%, 58%, 60%, 65%, etc., or any range of two of the above values, for example, 15%~40%, 40%~58%, 58%~65%, 25%~50%, etc.

[0103] The dispersant reduces the surface energy of the glass powder particles by adsorbing onto them, thus reducing particle agglomeration. The dispersant's mass percentage within the aforementioned range ensures long-term, uniform, and stable dispersion of the particles in the diluent, thereby reducing sedimentation and improving the film uniformity of the first coating 102. The dispersant completely volatilizes and decomposes during sintering. The mass percentage of the dispersant can be 0.5%, 1%, 2%, 3%, 4%, 4.5%, 5%, etc., or any range of two of the above values, for example, 0.5%~2%, 2%~4%, 4%~5%, 1%~4.5%, etc.

[0104] According to one embodiment of this application, the diluent includes one or more of water, alcohol solvents, ketone solvents, ester solvents, and ether solvents; wherein the alcohol solvent includes one or more of methanol, ethanol, isopropanol, and n-butanol; the ketone solvent includes one or more of acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; the ester solvent includes one or more of ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and propylene glycol monopropyl ether acetate; the ether solvent includes one or more of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether; the water includes one or two of deionized water and pure water; and the dispersant includes one or more of polycarboxylates, ammonium polyacrylates, sodium polyacrylates, polyethylene glycol, polyvinyl alcohol, and polyvinylpyrrolidone.

[0105] In this embodiment, the diluent is selected from the above-mentioned materials and can adjust the viscosity and fluidity of the first coating to make it suitable for specific coating processes such as spraying, dipping, and spin coating, so that a uniform and defect-free wet film can be formed on the substrate 101.

[0106] The dispersant is selected from the above materials and can be adsorbed on the surface of glass powder particles, reducing their surface energy and particle agglomeration, thereby improving the film uniformity of the first coating 102.

[0107] According to one embodiment of this application, the first coating further includes inorganic fillers, with the inorganic fillers accounting for 1% to 5% of the total mass of the first coating; and / or, the first coating further includes inorganic pigments, with the inorganic pigments accounting for 1% to 5% of the total mass of the first coating; and / or, the first coating further includes an adhesive, with the adhesive accounting for 0.05% to 5% of the total mass of the first coating.

[0108] In this embodiment, the inorganic filler's mass percentage within the aforementioned range can effectively improve the mechanical strength, wear resistance, acid and alkali resistance, and scratch resistance of the first coating 102, extending its service life. Simultaneously, the introduction of inorganic filler can adjust the coefficient of thermal expansion of the first coating 102, allowing it to better match the substrate 101, reducing thermal stress caused by thermal cycling, thereby improving the thermal shock resistance and bonding strength of the first coating 102. The mass percentage of inorganic filler can be 1%, 2%, 3%, 4%, 4.2%, 4.5%, 5%, etc., or a range of any two of the above values, for example, 1%~3%, 3%~5%, 2%~4%, 3%~4.5%, etc.

[0109] The inorganic pigment's mass percentage within the aforementioned range provides a stable and high-temperature resistant color for the first coating 102. Simultaneously, an amount of 1% to 5% is sufficient to achieve rich color expression, ensuring uniform and stable color without negatively impacting the sintering behavior, densification process, or final function of the first coating 102. The mass percentage of the inorganic pigment can be 1%, 2%, 3%, 4%, 4.2%, 4.5%, 5%, or any range of two of the aforementioned values, such as 1% to 3%, 3% to 5%, 2% to 4%, or 3% to 4.5%.

[0110] An adhesion promoter is used to enhance the adhesion between the first coating 102 and the substrate 101. When the mass percentage of the adhesion promoter is within the aforementioned range, it can promote the chemical or physical bonding between the first coating 102 and the substrate 101, reducing peeling of the first coating 102 under high temperatures or during thermal cycling. The mass percentage of the adhesion promoter can be 0.05%, 0.08%, 0.1%, 0.5%, 0.8%, 1%, 2%, 3%, 4%, 4.2%, 4.5%, 5%, etc., or a range of any two of the above values, for example, 0.05%~0.1%, 0.1%~1%, 1%~3%, 3%~5%, 2%~4%, 3%~4.5%, etc.

[0111] In some embodiments, the preparation method of the kitchen utensil 10 includes: (1) Pretreatment of substrate 101: Degreasing, rust removal and roughening treatment of the surface of substrate 101.

[0112] (2) Coating of the second coating 103: If a multilayer structure is required, a second coating 103 is first formed on the surface of the pretreated substrate 101. The second coating 103 can be formed by one of the following methods: sol-gel method, dip coating method, spray coating method, vapor deposition method, and enamel coating method. After the second coating 103 is applied, it is dried and cured at 80℃~150℃.

[0113] (3) Preparation of the first coating: Mix glass powder with diluent and dispersant, and add inorganic filler, inorganic pigment and adhesion agent as needed. Grind and disperse until the fineness is ≤15μm to obtain the first coating. The solid content of the first coating is 30wt%~80wt%, and the viscosity is 10mPa·s~500mPa·s. The viscosity can be adjusted according to the coating method.

[0114] (4) First coating: The first coating is applied to the surface of the substrate 101 or the second coating 103 by one of the following methods: spraying, dipping, roller coating, brushing, spin coating, casting, or screen printing. The wet film thickness after coating is 10μm~200μm.

[0115] (5) Drying and sintering: The substrate 101 coated with the first coating is placed in an oven and pre-dried at 30℃~120℃ for 10min~30min to remove the diluent. Then, the temperature is raised to 200℃~900℃ for heat treatment to melt the low softening temperature glass powder and form a dense and smooth first coating 102. The heat treatment time is preferably 0.1min~10 hours, preferably 1min~120min.

[0116] (6) Cooling: Cool to room temperature with the oven to obtain the finished kitchenware 10.

[0117] It should be noted that the second coating 103 application step can be flexibly set or canceled according to actual needs.

[0118] To make the technical problems, technical solutions, and beneficial effects solved by the embodiments of this application clearer, the following will provide a more detailed description in conjunction with the embodiments and accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its applications. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0119] The features and performance of this application will be further described in detail below with reference to the embodiments.

[0120] Example 1 Single-layer transparent coating for stainless steel woks: (1) Raw material preparation Glass powder: Zinc phosphate glass powder, softening temperature 480℃, particle size Dv 50 =5μm, unimodal distribution.

[0121] Diluent: Water.

[0122] Dispersant: Ammonium polyacrylate.

[0123] Adhesives: cobalt oxide and nickel oxide.

[0124] (2) Preparation of the first coating Mix 100 parts glass powder, 50 parts water, 2 parts ammonium polyacrylate, and 1 part adhesion promoter (cobalt oxide and nickel oxide in a 1:1 mass ratio) and grind them in a sand mill until the fineness is ≤10μm to obtain a uniform first coating.

[0125] (3) Pretreatment of substrate 101 Take a 304 stainless steel plate (2mm thick), and degrease and sandblast it to make the surface roughness Ra≈2μm.

[0126] (4) Coating and sintering The first coating was sprayed onto the surface of substrate 101, with a wet film thickness of 40 μm. It was placed in an oven and pre-dried at 100°C for 20 min, then heated to 650°C at a rate of 5°C / min and held for 30 min, followed by oven cooling.

[0127] Example 2 Single-layer black coating for aluminum alloy baking pans: (1) Raw material preparation Glass powder: Borosilicate glass powder, softening temperature 520℃, particle size Dv 50 =8μm.

[0128] Diluent: Ethanol.

[0129] Dispersant: Polycarboxylate.

[0130] Inorganic pigment: Iron oxide black (Fe3O4).

[0131] (2) Preparation of the first coating Mix 100 parts glass powder, 5 parts iron oxide black, 60 parts ethanol, and 3 parts polycarboxylate, and grind and disperse until the fineness is ≤15μm.

[0132] (3) Pretreatment of substrate 101 A 2mm thick 6061 aluminum alloy sheet was taken and subjected to degreasing and light sandblasting.

[0133] (4) Coating and sintering The first coating is sprayed onto the surface of the aluminum alloy plate, pre-dried at 80℃ for 30 minutes, then heated to 750℃ at 3℃ / min, held for 20 minutes, and cooled in the furnace.

[0134] Example 3 High-temperature, easy-to-clean coating for the energy-concentrating plate of gas stoves: (1) Application scenario description The heat-concentrating plate is one of the core components of a gas stove. Located around the burner, it is used to concentrate the heat of the flame and improve thermal efficiency. During use, the heat-concentrating plate is directly exposed to high-temperature flames (surface temperatures can reach 300℃~500℃) and is subjected to repeated contamination and carbonization from complex stains such as splattered oil, soy sauce, starch paste, and sugar syrup during cooking.

[0135] (2) Raw material preparation Glass powder: Zinc phosphate glass powder, softening temperature 500℃, with a bimodal particle size distribution: 70% coarse particles (8μm) and 30% fine particles (1.5μm), with a particle size ratio of approximately 5.3:1.

[0136] Diluent: Terpineol.

[0137] Dispersant: Ammonium polyacrylate.

[0138] Inorganic filler: nano-silica, particle size 20nm.

[0139] Inorganic pigments: A mixture of iron oxide black (Fe3O4) and cobalt oxide blue (CoAl2O4) pigments, with an addition amount of 5 parts, achieves a dark gray decorative effect.

[0140] (3) Preparation of the first coating Mix 100 parts glass powder, 5 parts mixed pigment, 50 parts terpineol, 3 parts ammonium polyacrylate, and 8 parts nano silica, and grind and disperse them in a sand mill until the fineness is ≤10μm to obtain a uniform first coating.

[0141] (4) Pretreatment of substrate 101 A 2mm thick 304 stainless steel stamping energy-concentrating disc is degreased and sandblasted to achieve a surface roughness Ra≈2.5μm. Then, compressed air is used to blow away the surface dust.

[0142] (5) Preparation of the second coating Prepare a silica sol mixture (SiO2 content 5%) and apply it evenly to the surface of the energy-concentrating disk (substrate 101) by spraying. Control the wet film thickness so that the thickness of the second coating 103 after drying is about 0.2 μm. Dry at 120℃ for 10 min.

[0143] (6) First coating 102 coating and sintering The first coating was applied onto the second coating 103 using an air spraying method, controlling the wet film thickness to 150 μm, so that the coating thickness after drying and sintering was approximately 85 μm. After spraying, the coating was allowed to stand and level for 10 minutes, and then placed in a mesh belt sintering furnace. It was first run in a 50°C pre-drying zone for 45 minutes to remove the diluent, and then entered the high-temperature zone, where the temperature was increased to 800°C at a rate of 5°C / min and held for 20 minutes. The furnace was then cooled to room temperature.

[0144] Example 4 High-temperature resistant and easy-to-clean coating for the energy-concentrating plate of a barbecue grill: (1) Application scenario description The heat-concentrating plate of the barbecue grill is located above the burner to distribute heat evenly and prevent grease from dripping and burning directly. During operation, temperatures can reach over 400℃, and it directly withstands dripping and carbonization of grease, marinades, and sauces.

[0145] (2) Raw material preparation Glass powder: Borosilicate glass powder, softening temperature 540℃, particle size Dv 50 =8μm.

[0146] Diluent: Ethanol + Terpineol (mass ratio 1:1).

[0147] Dispersant: Polycarboxylate.

[0148] Inorganic filler: nano-alumina, particle size 30nm.

[0149] Inorganic pigment: Iron oxide red (Fe2O3).

[0150] (3) Preparation of the first coating Mix 100 parts glass powder, 5 parts nano alumina, 3 parts iron oxide red, 60 parts mixed diluent, and 2 parts polycarboxylate, and grind and disperse them.

[0151] (4) Coating and sintering The same first coating 102 and second coating 103 process as in Example 3 was used, with a sintering temperature of 700°C and a holding time of 15 minutes.

[0152] Comparative Example 1 Similar to Example 3, except that: In step (2), the glass powder is replaced with high-temperature borosilicate glass powder. This glass powder has a softening temperature of 820℃, an average particle size of 6μm, and a unimodal distribution. The specific composition of the high-temperature borosilicate glass powder is (mass percentage): SiO2: 58%, B2O3: 7%, Al2O3: 23%, Na2O: 4%, K2O: 3%, CaO: 5%.

[0153] Step (6) The first coating 102 is applied and sintered. Finally, the temperature is increased to 900℃ at 5℃ / min, held for 20min, and then cooled to room temperature in the furnace.

[0154] The kitchen utensils 10 obtained in Examples 1-4 and Comparative Example 1 were subjected to performance tests, and Tables 1, 2, 3 and 4 were obtained.

[0155] The testing method is as follows: 1. Thickness testing method According to national standard GB / T13452.2 The coating thickness was tested in 2008, and the average value was taken after multiple tests.

[0156] 2. Open porosity testing method The open porosity of the sample was evaluated using the water absorption method. The sample was dried to constant weight at (105±2)℃, and the mass was recorded as m1. The sample was then immersed in deionized water under vacuum for 2 hours, removed, dried, and weighed, with the mass recorded as m2. The open porosity of the sample was calculated based on the ratio of the pore volume (calculated from the water absorption) to the total sample volume.

[0157] 3. Density testing method The microstructure density of the samples was characterized by scanning electron microscopy combined with image analysis. After cold mounting and polishing, SEM images of the sample cross-section were acquired at 200-500x magnification. The pore area was binarized and segmented using image analysis software, and the proportion of pore area to the total area of ​​the measurement area was calculated. The average value was taken as the density of the sample.

[0158] 4. Surface roughness testing methods The surface roughness of enamel was measured using a contact surface roughness tester. The probe tip radius was no greater than 5 μm, the sampling length was 2.5 mm, and the evaluation length was 12.5 mm. At least three test positions were selected on the sample surface, and at least three profile curves were measured at each position. The average value of the calculated Ra was taken as the surface roughness of the sample.

[0159] 5. Adhesion Test Method The adhesion of the samples was tested using a drop hammer impact tester. The required test parameters were: impact height H = 600 mm, drop hammer weight W = 2 LB; impact head diameter 16 mm ~ 22 mm; sample coating thickness controlled between 80 μm and 400 μm. The samples were placed stably on the impact tester's worktable, and three different locations were selected for each impact test. The adhesion grade was assessed based on the degree of enamel layer peeling off and exposing the substrate in the impact area. The required adhesion grade was ≥ 3.

[0160] Level 1: The impact site appears as a smooth plate; Level 2: The exposed area of ​​the substrate at the impact location is greater than two-thirds; Level 3: Less than one-third of the substrate area is exposed at the impact site; Level 4: The exposed area of ​​the substrate at the impact site is less than one-fifth; Level 5: No substrate is exposed at the impact site.

[0161] 6. Pencil Hardness Testing Method Pencil hardness testing was conducted according to GB / T6739: Standard pencils ranging from 6B to 9H were selected. The pencils were sharpened into a conical shape and the lead end face was horizontally sanded with 400# sandpaper, exposing approximately 3mm of the lead surface. The pencil was installed in the pencil hardness tester at a 45° angle to the sample surface. A standard load of approximately 7.5N was applied, and the pencil was dragged across the coating surface at a uniform speed of 0.5mm / s to 1mm / s, with a line length of approximately 6mm. Different hardness pencils were used for testing, and the highest pencil hardness that did not cause visible scratches on the coating was taken as the pencil hardness grade of the coating.

[0162] 7. (1) Test method for the energy-concentrating disk in Example 3: The energy-concentrating disk coating sample from Example 3 was placed on a heating plate and heated to 300°C. The composite stain test solution was thoroughly stirred and evenly applied to the sample surface with a brush, with a coating amount of approximately 0.2 mL / cm². 2 Heat at 300℃ for 30 minutes to completely carbonize and char the stain. Remove the sample and cool to room temperature. Gently wipe it 10 times with a sponge under a constant water flow (2L / min), and visually observe the surface residue. Repeat the above operation 10, 30, and 50 times to evaluate durability.

[0163] (2) The test results are shown in Table 1: Table 1

[0164] (3) Actual combustion test The energy-concentrating plate of Example 3 was installed on a household gas stove and used continuously for 30 days (cooking twice a day). No special cleaning was performed during this period; it was only rinsed during normal dishwashing. After 30 days, the surface of the energy-concentrating plate of Example 3 showed no obvious dirt accumulation, had a uniform color, and could be easily cleaned with a damp cloth.

[0165] 8. (1) Test method for the energy-concentrating plate of the barbecue grill in Example 4 The same composite stain test solution as in Example 3 was used, but the test temperature was increased to 400°C.

[0166] (2) The test results are shown in Table 2: Table 2

[0167] (3) Actual combustion test It is resistant to flame impact; after being directly burned by a butane spray gun for 30 seconds, the first coating 102 showed no change.

[0168] Table 3 Parameters of each embodiment and comparative example

[0169] Table 4 Test results for each embodiment and comparative example

[0170] As shown in Tables 1, 2, 3, and 4, the open porosity of the kitchenware in Examples 1-4 is lower than that in Comparative Example 1, while the density is higher. Furthermore, the performance test results are superior to those of Comparative Example 1. Comparative Example 1, due to the use of glass powder with a higher softening temperature and a higher sintering temperature, resulted in a coating with higher open porosity, lower density, significantly increased surface roughness, and poorer pencil hardness and adhesion. Carbonized oil stains were difficult to remove, failing to achieve an easy-to-clean performance. In contrast, this application, by selecting glass powder that meets the softening temperature range requirements and using a corresponding sintering process, achieves a first coating with low open porosity, high density, low surface roughness, good adhesion, and a pencil hardness of up to 9H. This reduces the penetration, adhesion, and carbonization of oil stains into the kitchenware at high temperatures, minimizing internal carbonization accumulation. Surface-adhered oil stains can be easily removed by wiping or rinsing with water, maintaining easy-to-clean performance for a long time.

[0171] The above are merely embodiments of this application and do not limit the scope of this patent application. Any equivalent structural or procedural changes made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A kitchen utensil, characterized in that, The material includes a substrate and a first coating disposed on one side of the substrate. The first coating includes glass, and the open porosity of the first coating is ≤10%, the density is ≥90%, and the surface roughness Ra is ≤0.2μm.

2. The kitchenware as described in claim 1, characterized in that, The first coating has an open porosity of ≤8% and a density of ≥92%.

3. The kitchenware as described in claim 2, characterized in that, The first coating has an open porosity of ≤5% and a density of ≥95%.

4. The kitchenware as described in claim 3, characterized in that, The first coating has an open porosity of ≤3% and a density of ≥97%.

5. The kitchenware as described in claim 1, characterized in that, The thickness of the first coating is 1μm to 500μm.

6. The kitchen utensil as described in claim 5, characterized in that, The thickness of the first coating is 20μm to 200μm.

7. The kitchenware as described in claim 1, characterized in that, The glass includes one or more of borosilicate glass, zinc phosphate glass, bismuth glass, aluminosilicate glass, and soda-lime silicate glass; and / or The substrate includes one or more of stainless steel, carbon steel, aluminum alloy, cast iron, microcrystalline glass, and ceramics.

8. The kitchenware as described in claim 1, characterized in that, The first coating further includes inorganic fillers, which include one or more of oxides, nitrides, carbides, and clay; and / or, The first coating also includes inorganic pigments, which include one or more of metal oxide pigments, mixed oxide pigments, silicate pigments, phosphate pigments, and borate pigments; Wherein, the metal oxide pigments include one or more of cobalt oxide, copper oxide, chromium oxide, iron oxide, or titanium dioxide; the mixed oxide pigments include one or more of cobalt black pigment, iron chromium black pigment, cobalt aluminum blue pigment, iron chromium brown pigment, zinc iron brown pigment, and manganese zinc iron black pigment; the silicate pigments include one or more of zirconium silicate vanadium yellow pigment, zirconium silicate iron pink pigment, zirconium silicate chromium green pigment, and manganese silicate violet pigment; the phosphate pigments include one or more of manganese phosphate violet pigment, iron phosphate brown pigment, cobalt phosphate blue pigment, and zinc phosphate pigment; the borate pigments include one or more of copper borate blue pigment, copper borate green pigment, cobalt borate blue pigment, and manganese borate violet pigment; and / or, The first coating further includes an adhesive, which includes one or more of cobalt oxide, nickel oxide, copper oxide, manganese oxide, and molybdenum trioxide.

9. The kitchenware as described in claim 8, characterized in that, The inorganic filler includes one or more of the following: nano-silica, alumina, zirconium oxide, titanium oxide, cerium oxide, zinc oxide, iron oxide, silicon carbide, silicon nitride, boron nitride, and clay.

10. The kitchenware as described in claim 1, characterized in that, The kitchenware further includes a second coating disposed between the substrate and the first coating. The second coating includes one or more of the following: a silica sol layer, a silicate layer, a phosphate layer, a borate layer, an aluminum sol layer, a titanium sol layer, a zirconium sol layer, an oxide layer, a nitride layer, a carbide layer, and an enamel layer. The oxide layer includes at least one of alumina, zirconium oxide, silicon dioxide, and titanium dioxide; the nitride layer includes at least one of silicon nitride, aluminum nitride, and titanium nitride; and the carbide layer includes at least one of silicon carbide, titanium carbide, and chromium carbide. The thickness of the second coating is 0.01μm to 500μm.

11. The kitchenware as described in claim 10, characterized in that, The thickness of the second coating is 0.1μm to 250μm.

12. The kitchenware as described in claim 11, characterized in that, The thickness of the second coating is 20μm~200μm.

13. A method for preparing a kitchen utensil as described in any one of claims 1 to 12, characterized in that, include: Provide base materials; A first coating is applied to the surface of the substrate; The first coating is cured at a first preset temperature to form a first coating layer; wherein the first coating includes glass powder, and the softening temperature of the glass powder is 300℃~800℃.

14. The method for preparing kitchen utensils as described in claim 13, characterized in that, The glass powder has at least one of the following characteristics: (1) The softening temperature of the glass powder is 400℃~650℃; (2) The glass powder includes one or more of the following: borosilicate glass powder, zinc phosphate glass powder, bismuth glass powder, aluminosilicate glass powder, and sodium-calcium-silicon glass powder; (3) The Dv of the glass powder 50 The range is from 0.01μm to 100μm; (4) The Dv of the glass powder 50 The range is from 1μm to 20μm; (5) The glass powder has a single-peak or multi-peak particle size distribution. When the glass powder has a multi-peak particle size distribution, the glass powder includes a first particle and a second particle, and the particle size ratio of the first particle and the second particle is (2~10):

1. The particle size of the first particle is greater than or equal to 10 μm and less than or equal to 20 μm, and the particle size of the second particle is greater than or equal to 1 micrometer and less than or equal to 10 micrometers.

15. The method for preparing kitchen utensils as described in claim 14, characterized in that, The first coating further includes a diluent and a dispersant; wherein, based on the total mass of the first coating, the mass percentage of the glass powder is 30% to 80%, the mass percentage of the diluent is 15% to 65%, and the mass percentage of the dispersant is 0.5% to 5%.

16. The method for preparing kitchenware as described in claim 15, characterized in that, The diluent includes one or more of water, alcohol solvents, ketone solvents, ester solvents, and ether solvents; wherein the alcohol solvent includes one or more of methanol, ethanol, isopropanol, and n-butanol; the ketone solvent includes one or more of acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; the ester solvent includes one or more of ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and propylene glycol monopropyl ether acetate; the ether solvent includes one or more of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether; and the water includes one or more of deionized water and purified water. The dispersant includes one or more of polycarboxylate, ammonium polyacrylate, sodium polyacrylate, polyethylene glycol, polyvinyl alcohol, and polyvinylpyrrolidone.

17. The method for preparing kitchen utensils as described in claim 14, characterized in that, The first coating also includes inorganic fillers, wherein the inorganic fillers account for 1% to 5% of the total mass of the first coating; and / or, The first coating also includes inorganic pigments, wherein the inorganic pigments constitute 1% to 5% of the total mass of the first coating; and / or, The first coating also includes an adhesion promoter, and the adhesion promoter accounts for 0.05% to 5% of the total mass of the first coating.

18. The method for preparing kitchen utensils as described in claim 13, characterized in that, The first preset temperature is 300℃~900℃.

19. The method for preparing kitchenware as described in claim 18, characterized in that, The first preset temperature is 300℃~700℃.

20. The method for preparing kitchenware as described in claim 19, characterized in that, The first preset temperature is 350℃~600℃.

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