Fluoroplastic non-stick cooker with improved wear resistance and preparation method of fluoroplastic non-stick cooker

Abstract

The invention relates to a fluoroplastic non-stick cooker with improved wear resistance and a preparation method thereof, and belongs to the technical field of non-stick cookers. The fluororesin non-stick cooker sequentially comprises an etching grain layer, a titanium transition layer and a fluororesin non-stick layer, the depth of the etching grain layer is 60-90 microns, and concave grains formed by the etching grain layer are filled with the fluororesin non-stick layer; the fluororesin non-stick layer comprises the following components in parts by weight: 100 parts of fluororesin powder, 5-8 parts of titanium oxide powder, 5-8 parts of aluminum oxide powder, 4-6 parts of silicon carbide powder, 2-4 parts of spodumene powder, 2-4 parts of sericite powder and 1-2 parts of pyrophyllite powder. The wear resistance of the fluoroplastic non-stick cooker is obviously improved, and the fluoroplastic non-stick cooker is stable in material, high in strength, not prone to falling off and good in lasting non-stick effect.

Description

TECHNICAL FIELD

[0001] The application relates to a fluoroplastic non-stick cookware with improved wear resistance and a preparation method thereof, and belongs to the technical field of non-stick cookware. BACKGROUND

[0002] Cookware is commonly used in daily life. During daily cooking, if the fire is too large, the pot is heated too much, and food is often easily stuck to the bottom of the pot, and burning occurs. In addition, the stuck and burned food is difficult to clean.

[0003] The advent of non-stick pots has brought great convenience to people's lives. Currently, the non-stick materials for cookware mainly include fluoroplastics, ceramic coatings and silicone resins. A non-stick coating is formed on the inner surface of the pot mainly by spraying, which can achieve a non-stick effect when heating food. Among them, fluoroplastics mainly include PTFE, PTOA, PFA, FEP and ETFE, ceramic coatings mainly are inorganic silicon with a silicon-oxygen bond structure, and organic silicone resin materials have a low surface energy and thus have a non-stick effect.

[0004] The non-stick performance of ceramic materials and organic silicone resins is poorer than that of fluoroplastics. The ceramic coating is also prone to falling off. The color of the organic silicone resin is prone to yellowing after being in contact with high temperature or open flame, and the hardness of the organic silicone resin is not good at high temperature. Fluoroplastics have obvious advantages in the application of cookware, and the non-stick performance is the best, and the coating is not easy to fall off.

[0005] However, fluoroplastics also have the problem of easy decomposition and release of toxic substances at high temperatures. In addition, the wear resistance of fluoroplastics needs to be improved, and they cannot be cleaned with a steel ball. In addition, the cooking tools cannot use an iron shovel, and a wooden shovel or a silicone shovel can be used as a stir-frying tool. In addition, the wear of fluoroplastics will also lead to a decrease in the non-stick performance. The use temperature is not recommended to exceed 260 DEG C, which can still cover most of the daily use scenarios, and the problem of wear resistance has become a limiting factor for the application of fluoroplastics.

[0006] Therefore, it is necessary to provide a fluoroplastic cookware coating with improved wear resistance and a non-stick pot product to solve the problems of the prior art and meet the market demand. SUMMARY

[0007] In order to solve the above problems, a fluoroplastic non-stick cookware with improved wear resistance and a preparation method thereof are provided. Through extensive research and testing, it is found that the addition of titanium oxide powder, aluminum oxide powder, silicon carbide powder, spodumene powder, sericite powder and talc powder in fluororesin powder and their cooperation can obviously improve the wear resistance of the non-stick coating, and the strength of the non-stick coating is higher. The fluororesin non-stick layer is filled in the recessed lines formed by the etched lines, and is not easy to fall off, and has a good long-lasting non-stick effect.

[0008] This application provides a wear-resistant and improved fluoroplastic non-stick cookware, characterized in that the fluoroplastic non-stick cookware sequentially comprises an etched texture layer, a titanium transition layer and a fluoroplastic non-stick layer, wherein the depth of the etched texture layer is 60~90μm, and the fluoroplastic non-stick layer fills the recessed texture formed by the etched texture layer. The fluororesin non-stick layer comprises, by weight, 100 parts of fluororesin powder, 5-8 parts of titanium dioxide powder, 5-8 parts of aluminum oxide powder, 4-6 parts of silicon carbide powder, 2-4 parts of spodumene powder, 2-4 parts of sericite powder, and 1-2 parts of pyrophyllite powder.

[0009] Optionally, the fluororesin powder has a particle size of 2~20μm, the titanium dioxide powder and aluminum oxide powder have a particle size of 0.5~1.5μm, the silicon carbide powder has a particle size of 50~100μm, and the spodumene powder, sericite powder and pyrophyllite powder have a particle size of 50~150μm.

[0010] Optionally, the fluoropolymer is selected from one or more of PTFE, PTOA, PFA, FEP, and ETFE.

[0011] Optionally, the fluoropolymer is PTFE or PFA.

[0012] Optionally, the titanium transition layer is also treated with a nitriding process.

[0013] Optionally, the nitriding process includes the following steps: placing the substrate in a nitriding furnace, heating the furnace temperature to 120~130℃, continuously introducing ammonia and nitrogen gas at a flow rate of 10~15L / min and a flow rate of 5~10L / min, continuing to raise the furnace temperature to 500~550℃, holding the temperature for 5~7h, and then cooling the temperature to 50~80℃ at a rate of 5~10℃ / min, stopping the introduction of nitrogen and ammonia gas, thus completing the nitriding process.

[0014] Optionally, the fluoropolymer non-stick layer is sprayed onto the titanium transition layer, and the substrate to be sprayed is preheated to 80~100℃ before spraying.

[0015] This application provides a method for preparing the above-mentioned wear-resistant improved fluoroplastic non-stick cookware, characterized in that the preparation method includes the following steps: 1) A raised or recessed etched pattern is formed on the inner surface of the cookware through chemical etching; 2) Prepare titanium powder and form a titanium transition layer on the inner surface of the substrate using plasma spraying technology, and then perform nitriding treatment on the titanium transition layer; 3) Prepare a fluoropolymer non-stick layer material and mix it evenly to obtain a powder mixture. Then, treat the powder mixture with plasma spraying to form a fluoropolymer non-stick layer with a thickness of 200 μm on the substrate surface. 4) After sintering, the wear-resistant and improved fluoroplastic non-stick cookware is obtained.

[0016] Optionally, the etching depth in step 1) is 60~90μm; and / or, In step 2), the thickness of the titanium transition layer is 30~40μm; and / or, In step 3), the thickness of the fluororesin non-stick layer is 200~220μm.

[0017] Optionally, in step 4), the sintering temperature is 380~420℃ and the sintering time is 5~15min.

[0018] The beneficial effects of this application include, but are not limited to: 1. According to the wear-resistant improved fluoroplastic non-stick cookware and its preparation method of this application, the inventors, through extensive research and experimental studies and tests, discovered that when titanium oxide powder, aluminum oxide powder, silicon carbide powder, spodumene powder, sericite powder and pyrophyllite powder are added to fluororesin powder and used in combination, the wear resistance of the non-stick coating is significantly improved when it is plasma sprayed onto the titanium transition layer, and the strength of the non-stick coating is higher, resulting in a more durable non-stick effect.

[0019] 2. The wear-resistant improved fluoroplastic non-stick cookware and its preparation method according to this application, wherein the fluoropolymer non-stick layer fills the recessed texture formed by the etched texture layer, resulting in higher overall strength and less flaking, and better long-lasting non-stick effect.

[0020] 3. The wear-resistant improved fluoroplastic non-stick cookware and its preparation method according to this application, by setting an etched texture layer, a titanium transition layer and a fluororesin non-stick layer, the intermediate titanium transition layer can not only play a good role in improving strength, but also improve the thermal conductivity of the non-stick coating. The titanium transition layer is also subjected to nitriding treatment to further improve the non-stick performance, thereby helping to obtain a better and more durable non-stick effect.

[0021] 4. According to the wear-resistant improved fluoroplastic non-stick cookware and its preparation method of this application, the substrate to be sprayed is preheated before the fluoropolymer non-stick layer is sprayed onto the titanium transition layer. This can improve the interfacial bonding performance between the fluoropolymer non-stick layer and the titanium transition layer during the spraying process, which is beneficial to improving the non-stick performance and bonding strength, and the non-stick coating is less likely to fall off. Detailed Implementation

[0022] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments. Unless otherwise specified, the raw materials and reagents in the embodiments of the present application are all purchased through commercial channels.

[0023] Example 1 S1. Prepare an aluminum alloy pot blank as a substrate, and form an etched texture on the inner surface by chemical etching with an etching depth of 75μm to form an etched texture layer. S2. Prepare titanium powder of about 20μm and form a 35μm thick titanium transition layer on the inner surface of the substrate by plasma spraying technology. The parameters of the plasma spraying process are: current 220A, voltage 30V, argon flow rate 1500L / H, hydrogen flow rate 80L / H, powder feeding gas flow rate 45L / H, powder feeding amount 15g / min, spraying distance 20cm, and spraying angle 45°. S3. Place the substrate in a nitriding furnace for nitriding treatment: heat the furnace to 125°C, continuously introduce ammonia and nitrogen gas at a flow rate of 12L / min and a flow rate of 8L / min, continue to raise the furnace temperature to 525°C, hold for 6 hours, and then reduce the temperature to 60°C at a rate of 8°C / min. Stop introducing nitrogen and ammonia gas to complete the nitriding treatment. S4. Prepare the non-stick coating material: Mix 100 parts of PTFE fluoropolymer powder, 7 parts of titanium dioxide powder, 6 parts of aluminum oxide powder, 5 parts of silicon carbide powder, 3 parts of spodumene powder, 3 parts of sericite powder, and 1.5 parts of pyrophyllite powder evenly to obtain a powder mixture; the particle size of the fluoropolymer powder in the powder mixture is 2~20μm, the particle size of the titanium dioxide powder and aluminum oxide powder is 0.5~1.5μm, the particle size of the silicon carbide powder is 50~100μm, and the particle size of the spodumene powder, sericite powder, and pyrophyllite powder is 50~150μm. S5. After the substrate is preheated to 90°C, the powder mixture is subjected to plasma spraying to form a 210μm thick fluoropolymer non-stick layer on the substrate surface. The conditions for plasma spraying include: plasma spray gun power of 55kW, spraying current of 600A, argon flow rate of 40L / min, hydrogen flow rate of 2L / min, powder feed rate of 8g / min, spraying distance of 10cm between the plasma spray gun and the substrate, spraying angle of 75°, and spray gun moving speed of 50mm / s.

[0024] After sintering at S6, 400℃, and 10min, wear-resistant fluoroplastic nonstick cookware is obtained.

[0025] Example 2 S1. Prepare an aluminum alloy pot blank as a substrate, and form an etched texture on the inner surface by chemical etching with an etching depth of 60μm to form an etched texture layer. S2. Prepare titanium powder of about 20μm and form a 30μm thick titanium transition layer on the inner surface of the substrate by plasma spraying technology. The parameters of the plasma spraying process are: current 220A, voltage 30V, argon flow rate 1500L / H, hydrogen flow rate 80L / H, powder feeding gas flow rate 45L / H, powder feeding amount 15g / min, spraying distance 20cm, and spraying angle 45°. S3. Place the substrate in a nitriding furnace for nitriding treatment: heat the furnace to 120°C, continuously introduce ammonia and nitrogen gas at a flow rate of 10L / min and a flow rate of 5L / min, continue to raise the furnace temperature to 500°C, hold for 7 hours, and then reduce the temperature to 80°C at a rate of 5°C / min. Stop introducing nitrogen and ammonia gas to complete the nitriding treatment. S4. Prepare the non-stick coating material: Mix 100 parts of PFA fluororesin powder, 5 parts of titanium dioxide powder, 5 parts of aluminum oxide powder, 4 parts of silicon carbide powder, 2 parts of spodumene powder, 2 parts of sericite powder, and 1 part of pyrophyllite powder evenly to obtain a powder mixture; the particle size of the fluororesin powder in the powder mixture is 2~20μm, the particle size of the titanium dioxide powder and aluminum oxide powder is 0.5~1.5μm, the particle size of the silicon carbide powder is 50~100μm, and the particle size of the spodumene powder, sericite powder, and pyrophyllite powder is 50~150μm. S5. After the substrate is preheated to 80°C, the powder mixture is subjected to plasma spraying to form a 200μm thick fluoropolymer non-stick layer on the substrate surface. The conditions for plasma spraying include: plasma spray gun power of 55kW, spraying current of 600A, argon flow rate of 40L / min, hydrogen flow rate of 2L / min, powder feed rate of 8g / min, spraying distance of 10cm between the plasma spray gun and the substrate, spraying angle of 75°, and spray gun moving speed of 50mm / s.

[0026] After sintering at S6, sintering temperature of 380℃, and sintering time of 15min, fluoroplastic non-stick cookware with improved wear resistance is obtained.

[0027] Example 3 S1. Prepare an aluminum alloy pot blank as a substrate, and form an etched texture on the inner surface by chemical etching with an etching depth of 690μm to form an etched texture layer. S2. Prepare titanium powder of about 20μm and form a 40μm thick titanium transition layer on the inner surface of the substrate by plasma spraying technology. The parameters of the plasma spraying process are: current 220A, voltage 30V, argon flow rate 1500L / H, hydrogen flow rate 80L / H, powder feeding gas flow rate 45L / H, powder feeding amount 15g / min, spraying distance 20cm, and spraying angle 45°. S3. Place the substrate in a nitriding furnace for nitriding treatment: heat the furnace to 130°C, continuously introduce ammonia and nitrogen gas at a flow rate of 15L / min and a flow rate of 10L / min, continue to raise the furnace temperature to 550°C, hold for 5 hours, and then reduce the temperature to 50°C at a rate of 10°C / min. Stop introducing nitrogen and ammonia gas to complete the nitriding treatment. S4. Prepare the non-stick coating material: Mix 100 parts of PTFE fluororesin powder, 8 parts of titanium dioxide powder, 8 parts of aluminum oxide powder, 6 parts of silicon carbide powder, 4 parts of spodumene powder, 4 parts of sericite powder, and 2 parts of pyrophyllite powder evenly to obtain a powder mixture; the particle size of the fluororesin powder in the powder mixture is 2~20μm, the particle size of the titanium dioxide powder and aluminum oxide powder is 0.5~1.5μm, the particle size of the silicon carbide powder is 50~100μm, and the particle size of the spodumene powder, sericite powder, and pyrophyllite powder is 50~150μm. S5. After the substrate is preheated to 100°C, the powder mixture is subjected to plasma spraying to form a 200~220μm thick fluororesin non-stick layer on the substrate surface. The conditions for plasma spraying include: plasma spray gun power of 55kW, spraying current of 600A, argon flow rate of 40L / min, hydrogen flow rate of 2L / min, powder feed rate of 8g / min, spraying distance of 10cm between the plasma spray gun and the substrate, spraying angle of 75°, and spray gun moving speed of 50mm / s.

[0028] After sintering at S6, 420℃, and 5min, wear-resistant fluoroplastic nonstick cookware is obtained.

[0029] Comparative Example 1 This comparative example is basically the same as Example 1, except that it does not contain an etched texture layer.

[0030] Comparative Example 2 This comparative example is basically the same as Example 1, except that it does not contain a titanium transition layer or a nitriding process.

[0031] Comparative Example 3 This comparative example is basically the same as Example 1, except that it does not contain spodumene powder.

[0032] Comparative Example 4 This comparative example is basically the same as Example 1, except that it does not contain sericite powder.

[0033] Comparative Example 5 This comparative example is basically the same as Example 1, except that it does not contain pyrophyllite powder.

[0034] Comparative Example 6 This comparative example is basically the same as Example 1, except that it does not contain silicon carbide powder.

[0035] Comparative Example 7 This comparative example is basically the same as Example 1, except that it does not contain titanium dioxide powder and aluminum oxide powder.

[0036] Comparative Example 8 This comparative example is basically the same as Example 1, except that there is no preheating step before spraying the fluororesin non-stick layer.

[0037] Test Example 1 The durability of the non-stick properties was tested and evaluated in accordance with GB / T 32388-2015.

[0038] The friction and wear test shall be conducted in accordance with GB / T1768-79. The weight before and after the friction and wear test shall be measured and weighed. The weight loss ratio shall be calculated according to the formula: weight loss ratio = (weight before friction - weight after friction) / weight before friction * 100%.

[0039] The adhesion of the non-stick coating was determined according to G98642-88.

[0040] The Vickers hardness of non-stick coatings was determined using a Vickers hardness tester in accordance with GB / T9790-1988.

[0041] The results are shown in Table 1 below.

[0042] Table 1 Test Results of Examples and Comparative Examples

[0043] Comparative Example 8 showed poor adhesion of the non-stick coating after spraying. This method was abandoned and no further preparation was carried out. Therefore, the performance tests in Table 1 were not performed.

[0044] Comparative Examples 6 and 7 were found to have poorer thermal conductivity compared to the example schemes, and were ultimately abandoned.

[0045] Based on the results of Examples 1-3 and Comparative Examples 1-5, it can be seen that the structure of the present application, which includes an etched texture layer, a titanium transition layer, and a fluoropolymer non-stick layer, fills the recessed textures formed by the etched texture layer. Furthermore, by using titanium oxide powder, aluminum oxide powder, silicon carbide powder, spodumene powder, sericite powder, and pyrophyllite powder in combination with fluoropolymer powder and applying them to the titanium transition layer via plasma spraying, the wear resistance of the non-stick coating is significantly improved, and the strength and adhesion of the non-stick coating are higher, resulting in a more durable non-stick effect.

[0046] The above description is merely an embodiment of this application, and the scope of protection of this application is not limited to these specific embodiments, but is determined by the claims of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the technical concept and principles of this application should be included within the scope of protection of this application.

Claims

1. A wear-resistant and improved fluoroplastic non-stick cookware, characterized in that, The fluoropolymer non-stick cookware comprises, in sequence, an etched texture layer, a titanium transition layer, and a fluoropolymer non-stick layer. The depth of the etched texture layer is 60~90μm, and the fluoropolymer non-stick layer fills the recessed textures formed by the etched texture layer. The fluororesin non-stick layer comprises, by weight, 100 parts of fluororesin powder, 5-8 parts of titanium dioxide powder, 5-8 parts of aluminum oxide powder, 4-6 parts of silicon carbide powder, 2-4 parts of spodumene powder, 2-4 parts of sericite powder, and 1-2 parts of pyrophyllite powder.

2. The wear-resistant improved fluoroplastic non-stick cookware according to claim 1, characterized in that, The fluororesin powder has a particle size of 2~20μm, the titanium dioxide powder and aluminum oxide powder have a particle size of 0.5~1.5μm, the silicon carbide powder has a particle size of 50~100μm, and the spodumene powder, sericite powder and pyrophyllite powder have a particle size of 50~150μm.

3. The wear-resistant improved fluoroplastic non-stick cookware according to claim 1, characterized in that, The fluoropolymer is selected from one or more of PTFE, PTOA, PFA, FEP, and ETFE.

4. The wear-resistant improved fluoroplastic non-stick cookware according to claim 3, characterized in that, The fluoropolymer is PTFE or PFA.

5. The wear-resistant improved fluoroplastic non-stick cookware according to claim 1, characterized in that, The titanium transition layer is also treated with a nitriding process.

6. The wear-resistant improved fluoroplastic nonstick cookware according to claim 5, characterized in that, The nitriding process includes the following steps: placing the substrate in a nitriding furnace, heating the furnace to 120~130℃, continuously introducing ammonia and nitrogen gas at a flow rate of 10~15L / min and a flow rate of 5~10L / min, continuing to raise the furnace temperature to 500~550℃, holding it at that temperature for 5~7h, and then cooling it down to 50~80℃ at a cooling rate of 5~10℃ / min, stopping the introduction of nitrogen and ammonia gas, thus completing the nitriding process.

7. The wear-resistant improved fluoroplastic non-stick cookware according to claim 1, characterized in that, The fluororesin non-stick layer is sprayed onto the titanium transition layer, and the substrate to be sprayed is preheated to 80~100℃ before spraying.

8. The method for preparing the wear-resistant improved fluoroplastic non-stick cookware according to any one of claims 1 to 7, characterized in that, The preparation method includes the following steps: 1) A raised or recessed etched pattern is formed on the inner surface of the cookware through chemical etching; 2) Prepare titanium powder and form a titanium transition layer on the inner surface of the substrate using plasma spraying technology, and then perform nitriding treatment on the titanium transition layer; 3) Prepare a fluoropolymer non-stick layer material and mix it evenly to obtain a powder mixture. Then, treat the powder mixture with plasma spraying to form a fluoropolymer non-stick layer with a thickness of 200 μm on the substrate surface. 4) After sintering, the wear-resistant and improved fluoroplastic non-stick cookware is obtained.

9. The method for preparing the wear-resistant and improved fluoroplastic non-stick cookware according to claim 8, characterized in that, In step 1), the etching depth is 60~90μm; and / or, In step 2), the thickness of the titanium transition layer is 30~40μm; and / or, In step 3), the thickness of the fluororesin non-stick layer is 200~220μm.

10. The method for preparing the wear-resistant improved fluoroplastic non-stick cookware according to claim 8, characterized in that, In step 4), the sintering temperature is 380~420℃ and the sintering time is 5~15min.

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