Metal non-stick coating and preparation method thereof

Abstract

The invention discloses a metal non-stick coating and a preparation method. The coating comprises 20-30 parts of low-melting-point glass powder, 10-20 parts of a two-dimensional material, 10-20 parts of a spherical material, 10-20 parts of a rod-like material, 5-10 parts of a high-temperature pigment and 20-30 parts of a water-based carrier. The metal non-stick coating is sintered on the base material at low temperature, and the low-melting-point glass powder is used as a cladding sealing film forming substance and is cladded on the metal base material by adopting a sintering process, so that the hardness of the coating is higher than that of metal, the coating is not afraid of being scratched by metal kitchenware and hard food materials, and the metal non-stick coating is not prone to being scratched by the metal kitchenware and the hard food materials during conventional operations such as decocting and stir-frying. The coating is not prone to falling off or oxygenolysis, the concave-convex lotus leaf structure with the microscopic surface is formed through cooperation of the two-dimensional material, the spherical material, the rod-shaped material, the high-temperature pigment, the water-based carrier and other materials, and when food is cooked, the concave-convex lotus leaf structure can reduce contact between the food and the bottom of the pan, the Leidenfrost effect is formed, and the food is prevented from sticking to the pan.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to a metal non-stick coating and a preparation method thereof. Background Art

[0002] A non-stick pan is a pan that does not stick to the bottom when cooking. Because the bottom of the pan is coated with a non-stick coating, the common ones with the best non-stick performance are Teflon coatings and ceramic coatings. Pot products mainly include aluminum pans, stainless steel pans, iron enamel pans, iron pans and non-stick pans, etc. These pans have their own advantages and disadvantages. Among them, because the non-stick pan overcomes all the disadvantages of traditional pans, it is easy to clean, can be wiped clean with a light wipe, can easily fry and stir-fry food without sticking to the bottom, can minimize the use of oil, and the kitchen is clean with less fumes, so it is widely loved by people.

[0003] Traditional non-stick coatings are generally Teflon and porcelain film coatings. Their hardness is lower than that of metals. When using metal kitchen utensils such as spatulas and steel wool balls, the coating will be damaged. When frying and stir-frying relatively hard ingredients such as large bones and shells, the coating will also be scratched. At the same time, the coating will emit fumes, burn and fall off at high temperatures. In addition, carcinogenic substance PFOA is used in the synthesis process of Teflon materials, and harmful substances may be released from Teflon materials at high temperatures, which is also a problem that people are more concerned about. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, one of the purposes of the present invention is to provide a metal non-stick coating to solve the above-mentioned traditional technical problems.

[0005] Another purpose of the present invention is to provide a preparation method of the above-mentioned metal non-stick coating. The preparation method is simple to operate and suitable for large-scale production.

[0006] One of the purposes of the present invention is achieved by adopting the following technical solutions:

[0007] A metal non-stick coating, comprising the following components in parts by weight:

[0008] 20-30 parts of low-melting-point glass powder, 10-20 parts of two-dimensional material, 10-20 parts of spherical material, 10-20 parts of rod-shaped material, 5-10 parts of high-temperature pigment, 20-30 parts of water-based carrier;

[0009] Among them, the low-melting-point glass powder is an inorganic non-metallic material, and the properties of the inorganic non-metallic material are: melting point 550°C - 650°C, thermal expansion coefficient (12-15)×10 -6 / K.

[0010] That is, in the present invention, through low-temperature sintering on a substrate, using low-melting-point glass powder as a cladding and sealing film-forming substance, and adopting a sintering process to be cladded on a metal substrate, the hardness of the coating is higher than that of the metal, and it is not afraid of being scratched by metal cooking utensils and hard food ingredients. During conventional cooking operations such as frying and stir-frying, the coating will not fall off or decompose by oxidation. And through the cooperation of materials such as two-dimensional materials, spherical materials, rod-shaped materials, high-temperature pigments, and aqueous carriers, a microscopic concave-convex lotus leaf structure is formed on the surface. When cooking food, this concave-convex lotus leaf structure can reduce the contact between the food and the bottom of the pot, forming the Leidenfrost effect and preventing the food from sticking to the pot.

[0011] Further, the mass ratio of the spherical material to the rod-shaped material is 1:(0.8 - 1.2), making the effect of the concave-convex lotus leaf structure better, so as to further improve the effect of preventing the food from sticking to the pot.

[0012] Further, the low-melting-point glass powder includes the following components in parts by weight:

[0013] Al2O3 5 - 10 parts, ZnO 10 - 15 parts, SiO2 25 - 35 parts, K2O 3 - 5 parts, Na2O 15 - 20 parts, B2O3 5 - 10 parts, TiO2 3 - 5 parts, BaO 3 - 5 parts, P2O5 1 - 2 parts.

[0014] The low-melting-point glass powder is formed by melting the above raw materials after mixing them evenly at high temperature, and then finely grinding them into inorganic non-metallic material powder. The average particle size of the inorganic non-metallic material powder is 5 - 20um.

[0015] Further, the two-dimensional material is synthetic mica powder and / or cubic boron nitride powder, and the average particle size of the two-dimensional material is 5 - 20um.

[0016] Further, the spherical material is spherical or quasi-spherical particulate powder. Among them, the spherical material is spherical or quasi-spherical SiO2 powder and / or Al2O3 powder. Preferably, the spherical material is spherical or quasi-spherical synthetic SiO2 powder and / or synthetic Al2O3 powder, with an average particle size of 20 - 50um and a purity of more than 99.5%.

[0017] Further, the rod-shaped material is fibrous powder. Among them, the rod-shaped material is one or more of glass fiber powder, diamond powder, and whisker silicon powder, with an average particle size of 10 - 30um.

[0018] Further, the high-temperature pigment is inorganic oxide high-temperature resistant pigment powder. Among them, the high-temperature pigment is one or more of iron oxide, cobalt oxide, and copper oxide chromium, with an average particle size of 5 - 20um.

[0019] Further, the aqueous carrier includes the following components in parts by weight:

[0020] 20 - 30 parts of high - viscosity resin, 1 - 2 parts of dispersant, 0.2 - 0.3 parts of defoamer, 0.1 - 0.2 parts of wetting agent, 1 - 3 parts of anti - settling agent, 0.1 - 0.2 parts of leveling agent, and 65 - 70 parts of water.

[0021] Further preferably, the high - viscosity resin is characterized in that: the solid content is 20 - 40 wt%, the viscosity is 100000 - 200000 mPa·s, and it has good flow, leveling and other properties. Specifically, the high - viscosity resin is one or more of aqueous acrylic resin, aqueous polyester resin, modified cellulose resin, and polyethylene oxide resin.

[0022] Further, the dispersant is a polyether - type dispersant and / or an acrylic - type dispersant, and these dispersants are all commonly used polyether - type or acrylic - type dispersants on the market.

[0023] Further, the defoamer is a silicone - type defoamer, and this defoamer is a commonly used silicone - type defoamer on the market.

[0024] Further, the wetting agent is a polyether - type wetting agent and / or a silicone - type wetting agent, and this wetting agent is a commercially available polyether - type or silicone - type wetting agent.

[0025] Further, the anti - settling agent is bentonite and / or fumed silica, and this anti - settling agent is commercially available bentonite or fumed silica.

[0026] Further, the leveling agent is an acrylic - type leveling agent and / or a silicone - type leveling agent, and this leveling agent is a commercially available acrylic - type or silicone - type leveling agent.

[0027] The preparation steps of the above - mentioned aqueous carrier are as follows:

[0028] Mix the high - viscosity resin, dispersant, defoamer, wetting agent, anti - settling agent, leveling agent and water evenly, and that's it.

[0029] The second object of the present invention is achieved by the following technical solution:

[0030] A preparation method of a metal non - stick coating, including the following preparation steps:

[0031] S1: Mix the low - melting - point glass powder, two - dimensional material, spherical material, rod - shaped material, high - temperature pigment and aqueous carrier evenly, and then use a high - speed mixer or a three - roll mill to disperse them evenly to obtain a functional coating;

[0032] S2: When in use, spray the functional coating on the surface of the metal cookware, control the coating thickness to be 60 - 150 um, and sinter at 800 - 850 °C. After sintering, a metal non - stick coating is formed on the surface of the metal cookware.

[0033] In the above steps, the metal cookware is a cast iron pot, a stainless steel pot, an iron enamel pot, etc. The sintering time is determined according to the size and thickness of the base material. During the sintering process, the inorganic coating melts into a film at high temperature to form a coating that is firm, insulating, high-temperature resistant, corrosion-resistant, and has good weather resistance.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] 1. The metal non-stick coating of the present invention is sintered on the base material at low temperature. Using low-melting glass powder as the cladding and sealing film-forming substance, and adopting the sintering process, it is clad on the metal base material, making the hardness of the coating higher than that of the metal, not afraid of being scratched by metal cookware and hard food ingredients. During conventional cooking operations such as frying and stir-frying, the coating will not fall off, oxidize and decompose. Through the cooperation of materials such as two-dimensional materials, spherical materials, rod-shaped materials, high-temperature pigments, and water-based carriers, a microscopic concave-convex lotus leaf structure is formed on the surface. When cooking food, this concave-convex lotus leaf structure can reduce the contact between the food and the bottom of the pot, form the Leidenfrost effect, and prevent the food from sticking to the pot.

[0036] 2. All materials of the metal non-stick coating of the present invention adopt food-grade raw materials and will not affect human health.

[0037] 3. The metal non-stick coating of the present invention adopts water-based environmental protection materials, including water-based resin, water-based environmental protection solvent, and water-based additive, and adjusts the rheological parameters to make it suitable for processes such as spraying and dipping, with the advantages of environmental protection and harmlessness. Specific Embodiments

[0038] Next, in combination with specific embodiments, the present invention will be further described. It should be noted that on the premise of no conflict, the following-described embodiments or technical features can be combined arbitrarily to form new embodiments.

[0039] In the following embodiments:

[0040] The water-based carrier includes the following components in parts by weight:

[0041] 25 parts of high-viscosity resin, 1 part of dispersant, 0.2 part of defoamer, 0.1 part of wetting agent, 1 part of anti-settling agent, 0.1 part of leveling agent, and 70 parts of water.

[0042] Among them, water-based carrier 1 adopts water-based acrylic resin, water-based carrier 2 adopts water-based polyester resin, water-based carrier 3 adopts modified cellulose resin, and water-based carrier 4 adopts polyethylene oxide resin.

[0043] The water-based acrylic resin is purchased from Henan Hairui Chemical Products Co., Ltd., with a solid content of 20-40 wt%, and a viscosity of 100000-200000 mPa·s;

[0044] The water-based polyester resin was purchased from IGM Resins and was Photomer 5930 (amine-modified polyether acrylate resin) with a solid content of 20-40 wt % and a viscosity of 100,000-200,000 mPa·s.

[0045] The modified cellulose resin was purchased from Jinzhou Honghai Cellulose Co., Ltd. and is hydroxypropyl methylcellulose with a solid content of 20-40 wt % and a viscosity of 100,000-200,000 mPa·s.

[0046] Polyethylene oxide resin was purchased from Shandong Yonglida New Material Technology Co., Ltd. with a solid content of 20-40 wt% and a viscosity of 100,000-200,000 mPa·s;

[0047] The dispersant was purchased from Zhuhai Jintuan Chemical Co., Ltd.

[0048] The defoaming agent was purchased from Shandong Baozhongbao New Materials Co., Ltd. as an organosilicon defoaming agent;

[0049] The wetting agent was purchased from Hubei Longsheng Sihai New Materials Co., Ltd. as an organosilicon wetting agent;

[0050] The anti-settling agent was fumed silica, purchased from Zhejiang Yamei Nano Technology Co., Ltd.;

[0051] The leveling agent was purchased from Hangzhou Baoerde New Material Technology Co., Ltd. BD-3134 silicone leveling agent;

[0052] Synthetic mica powder was purchased from Guangzhou Yuanyuan New Materials Co., Ltd., with an average particle size of 5-20 μm;

[0053] Cubic boron nitride powder was purchased from Anhui Kerun Nanotechnology Co., Ltd., with an average particle size of 5-20 μm.

[0054] Spherical synthetic SiO2 powder was purchased from Jiangsu Huimai Powder Technology Co., Ltd., with an average particle size of 20-50 μm;

[0055] Spherical synthetic Al2O3 powder was purchased from Forsman Technology (Beijing) Co., Ltd., with an average particle size of 20-50 μm;

[0056] Glass fiber powder was purchased from Taishan Glass Fiber Co., Ltd., with an average particle size of 10-30 μm;

[0057] Diamond powder was purchased from Zhengzhou Besta Superhard Materials Co., Ltd., with an average particle size of 10-30 μm;

[0058] Whisker silicon powder was purchased from Shandong Hanxinzun New Materials Co., Ltd., with an average particle size of 10-30 μm;

[0059] The high-temperature pigment is iron oxide, purchased from Shandong Jinjing Technology Co., Ltd., and its average particle size is 5 - 20 um.

[0060] The low-melting-point glass powder includes the following components in parts by weight: 6 parts of Al2O3, 12 parts of ZnO, 30 parts of SiO2, 4 parts of K2O, 18 parts of Na2O, 6 parts of B2O3, 4 parts of TiO2, 4 parts of BaO, and 1 part of P2O5. The low-melting-point glass powder is prepared by mixing the above raw materials and then melting them at high temperature, and then finely grinding them into inorganic non-metallic material powder, and the average particle size of the inorganic non-metallic material powder is 5 - 20 um.

[0061] Glass powder 1 (without SiO2) includes the following components in parts by weight: 6 parts of Al2O3, 12 parts of ZnO, 4 parts of K2O, 18 parts of Na2O, 6 parts of B2O3, 4 parts of TiO2, 4 parts of BaO, and 1 part of P2O5. Its preparation method is the same as that of the above low-melting-point glass powder.

[0062] Glass powder 2 (without Al2O3) includes the following components in parts by weight: 12 parts of ZnO, 30 parts of SiO2, 4 parts of K2O, 18 parts of Na2O, 6 parts of B2O3, 4 parts of TiO2, 4 parts of BaO, and 1 part of P2O5. Its preparation method is the same as that of the above low-melting-point glass powder.

[0063] I. The examples are shown in Table 1 below:

[0064] Table 1

[0065]

[0066]

[0067] The preparation method adopted is

[0068] S1: After mixing the low-melting-point glass powder, two-dimensional material, spherical material, rod-shaped material, high-temperature pigment and water-based carrier, use a high-speed mixer or three-roll mill to disperse them evenly to obtain a functional coating;

[0069] S2: When in use, spray the functional coating on the surface of the metal cookware, control the coating thickness at 100 um, and sinter it at 800 - 850 °C to form a metal non-stick coating on the surface of the metal cookware after sintering.

[0070] II. The comparative examples are shown in Table 2 below:

[0071] Table 2

[0072]

[0073]

[0074] Its preparation method is similar to the above.

[0075] III. Performance Testing

[0076] 1. Adhesion Testing

[0077] The adhesion testing method for the coating is GB9286 - 1998, which is divided into grades 0 to 5. The best is grade 0, indicating that the cutting edge is completely smooth, without a single grid peeling off, and the adhesion is the best.

[0078] 2. Hardness Testing

[0079] The hardness testing method for the coating is GB / T6739 - 2022.

[0080] 3. Impact Resistance Testing

[0081] The impact resistance testing method is GB / T 1732 - 1993.

[0082] 4. Abrasion Resistance Testing

[0083] The abrasion resistance testing method is GB / T 1768 - 1979. The evaluation standard for abrasion resistance is the weight loss after grinding 200 circles with a grinding wheel under a 250g weight.

[0084] 5. Thermal Stability Testing

[0085] The thermal stability of the coating is characterized by measuring its 5% thermal weight loss temperature. The instrument used for testing and characterization is the synchronous thermal analyzer TGA / DSC1, and the sample testing conditions are: in an air atmosphere.

[0086] 6. Corrosion Resistance Testing

[0087] The non - stick pan coating is immersed in a 10% hydrochloric acid solution, a 10% sodium hydroxide solution, or a 1mol / L sodium chloride solution for a total of 10 days, and the surface of the film is observed.

[0088] 7. Non - stick Pan Testing

[0089] The test is carried out according to GB / T 32095.1 - 2015. The metal cooking utensil is a cast iron pan. Among them, the test method for wear - resistant non - stick is: fry an egg after 5000 times with a scouring pad and take it out with a metal spatula. If there is no damage, it is grade I; if there is damage when taking it out and the residue can be removed by gently wiping with a wet gauze, it is grade II; the test method for LNE long - lasting non - stick is: test 10 cycles, and if two consecutive grade III results appear, it is judged as unqualified.

[0090] 8. The test results are shown in Table 3 below.

[0091] Table 3

[0092]

[0093] The above embodiments are only the preferred embodiments of the present invention, and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention.

Claims

1. A metal non-stick coating, characterized in that, It comprises the following components in parts by weight: 20 - 30 parts of low - melting - point glass powder, 10 - 20 parts of two - dimensional material, 10 - 20 parts of spherical material, 10 - 20 parts of rod - shaped material, 5 - 10 parts of high - temperature pigment, 20 - 30 parts of water - based carrier; Among them, the low-melting glass powder is an inorganic non-metallic material, and the properties of the inorganic non-metallic material are: melting point 550°C - 650°C, thermal expansion coefficient (12 - 15)×10 -6 / K.

2. The metal non-stick coating according to claim 1, wherein The low - melting - point glass powder comprises the following components in parts by weight: 5 - 10 parts of Al2O3, 10 - 15 parts of ZnO, 25 - 35 parts of SiO2, 3 - 5 parts of K2O, 15 - 20 parts of Na2O, 5 - 10 parts of B2O3, 3 - 5 parts of TiO2, 3 - 5 parts of BaO, 1 - 2 parts of P2O5.

3. The metal non-stick coating according to claim 2, characterized in that, The average particle size of the low - melting - point glass powder is 5 - 20um.

4. The non-stick metal coating according to claim 1, characterized in that, The two - dimensional material is synthetic mica powder and / or cubic boron nitride powder.

5. The metal non-stick coating according to claim 1, characterized in that, The spherical material is spherical or quasi - spherical synthetic SiO2 powder and / or synthetic Al2O3 powder, and its average particle size is 20 - 50um.

6. The metal non-stick coating according to claim 5, characterized in that, The rod - shaped material is one or more of glass fiber powder, diamond powder, and whisker silicon powder, and its average particle size is 10 - 30um.

7. The metal non-stick coating according to claim 1, wherein The high - temperature pigment is an inorganic oxide high - temperature - resistant pigment powder.

8. The non-stick metal coating according to claim 1, characterized in that, The water - based carrier comprises the following components in parts by weight: 20 - 30 parts of high - viscosity resin, 1 - 2 parts of dispersant, 0.2 - 0.3 parts of defoamer, 0.1 - 0.2 parts of wetting agent, 1 - 3 parts of anti - settling agent, 0.1 - 0.2 parts of leveling agent, 65 - 70 parts of water.

9. The metal non-stick coating according to claim 8, characterized in that, The high - viscosity resin is one or more of water - based acrylic resin, water - based polyester resin, modified cellulose resin, and polyethylene oxide resin with a solid content of 20 - 40wt% and a viscosity of 100000 - 200000mPa·s; the dispersant is a polyether - type dispersant and / or an acrylic - type dispersant; the defoamer is a silicone - type defoamer; the wetting agent is a polyether - type wetting agent and / or a silicone - type wetting agent; the anti - settling agent is bentonite and / or fumed silica; the leveling agent is an acrylic - type leveling agent and / or a silicone - type leveling agent.

10. A method for preparing a metal non-stick coating according to any one of claims 1-9, characterized in that, It comprises the following preparation steps: S1: After mixing the low - melting - point glass powder, two - dimensional material, spherical material, rod - shaped material, high - temperature pigment, and water - based carrier evenly, then use a high - speed mixer or a three - roll mill to disperse them evenly to obtain a functional coating; S2: During use, spray the functional coating on the surface of the metal cookware, control the coating thickness at 60 - 150um, and sinter it at 800 - 850°C. After sintering, a metal non - stick coating is formed on the surface of the metal cookware.

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