A durable non-stick coating and its preparation method

Abstract

This invention relates to the field of coating technology, and in particular to a durable non-stick pan coating and its preparation method. The coating is composed of the following components: 8-10 parts organic binder, 3-5 parts silica sol, 6-9 parts filler, 1-2 parts modified hexagonal boron nitride, 0.1-0.3 parts water-based bentonite, 0.1-0.2 parts dispersant, 0.1-0.3 parts defoamer, and 5-7 parts water. This invention enhances the binding effect of hexagonal boron nitride in the coating by utilizing the bonding sites of copper and iron particles on the surface of the boron nitride. This promotes efficient bonding of the boron nitride to materials, forming a neatly arranged and dense coating structure, improving adhesion to the substrate, increasing environmental resistance, and enabling the non-stick pan to maintain good performance even after prolonged use.

Description

Technical Field

[0001] This invention relates to the field of coating technology, and in particular to a durable non-stick pan coating and its preparation method. Background Technology

[0002] As people's living standards continue to improve, their requirements for kitchen utensils are becoming increasingly higher. Due to their excellent anti-stick properties and easy-to-clean characteristics, non-stick coatings are widely used in everyday kitchen utensils such as rice cookers, non-stick pans, range hoods, and gas stoves, and are highly favored by consumers.

[0003] There are many methods for creating non-stick coatings, but most current technologies focus on using fluorine-containing materials, which have certain shortcomings in durability and safety, and lack targeted integration of materials. For example, patent number CN202210934700.2 describes a high-temperature resistant, wear-resistant, hydrophilic inorganic coating, its preparation method, and its application. The coating includes component A, component B, and water. By weight, component A includes: 45-75 parts silica sol, 10-20 parts γ-alumina, 0.5-5 parts α-alumina, 1-5 parts cobalt black, 0.1-5 parts polyethylene glycol, and 0.1-5 parts leveling agent; component B includes: 20-30 parts titanium powder, 1-2 parts γ-alumina, 1.2-30 parts carbon material, and 1-5 parts leveling agent. This high-temperature resistant, wear-resistant, hydrophilic inorganic coating is formed by spraying, sintering at 500-600℃, and heat preservation. The materials used in some applications lack targeted modifications, resulting in insufficient integration in actual use. For example, patent number CN202110527260.4 describes a non-stick pan coating based on an interpenetrating network structure. This coating is composed of an epoxy resin system and a polyurethane resin system mixed in a mass ratio of 5-7:2-3. By mass, the epoxy resin system includes: 30-50 parts alicyclic epoxy compound, 80-90 parts glycidyl amine resin, 3-5 parts modified carbon fiber, 2-5 parts pentaerythritol tetrakis(3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid), 3-5 parts zirconia ceramic, 11-12 parts alumina ceramic, 10-15 parts zinc oxide ceramic, 13-17 parts silicon nitride ceramic, and 2-5 parts polyethylene wax. The fillers used in this coating lack in-molecular modification, failing to leverage the structural strength advantages of the coating. Therefore, research into deep modification of current materials to enhance non-stick pan coatings is highly necessary. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a durable non-stick pan coating and its preparation method. By selectively choosing connecting materials and fillers, the non-stick pan coating is strengthened, thus improving its durability. The specific technical solution is as follows:

[0005] A durable nonstick coating, by weight, is made of the following components:

[0006] 8-10 parts organic binder, 3-5 parts silica sol, 6-9 parts filler, 1-2 parts modified hexagonal boron nitride, 0.1-0.3 parts water-based bentonite, 0.1-0.2 parts dispersant, 0.1-0.3 parts defoamer, and 5-7 parts water;

[0007] The method for preparing the modified hexagonal boron nitride is as follows:

[0008] (1) Mix potassium hydroxide and deionized water at a mass ratio of 2:3-4, seal and let stand for 11-14 min to obtain solution A;

[0009] Mix 1-3 parts of ferric citrate with 110-130 parts of deionized water and stir for 4-7 minutes. Add 20-30 parts of hexagonal boron nitride to the solution to obtain mixed solution B. Take the supernatant from solution A, take 2-6 parts and inject it into mixed solution B. Stir for 7-10 minutes, add 2-3 parts of carrageenan and continue stirring for 30-50 minutes.

[0010] (2) Centrifuge the above-treated mixed solution B, wash with ethanol 2-3 times, then wash with deionized water 1-2 times, take the precipitate, heat and dry it, place the dried product in a calcining furnace, and calcine at 400-430℃ for 15-20 min under oxygen conditions; lower the temperature to room temperature, introduce carbon monoxide, heat at 700-710℃ for 20-30 min, and lower the temperature to room temperature to obtain powder;

[0011] Mix the powder obtained above with copper sulfate solution, heat the temperature to 33-35℃, stir for 20-30 minutes, filter, rinse the filter residue with deionized water 2-3 times, and dry.

[0012] Furthermore, the dispersant is BYK-161.

[0013] Furthermore, the defoamer is BYK-A530.

[0014] Furthermore, the organic adhesive is an acrylate.

[0015] Furthermore, the filler is composed of the following raw materials: 8-10 parts alumina, 1-2 parts titanium dioxide, 5-7 parts magnesium oxide, and 2-4 parts zinc oxide.

[0016] Furthermore, the amount of carbon monoxide used is 10-15% of the mass of hexagonal boron nitride.

[0017] Furthermore, the mass ratio of the powder to the copper sulfate solution is 1:50-67.

[0018] Furthermore, the copper sulfate solution has a mass fraction of 5-6.4%.

[0019] The method for preparing the durable non-stick pan coating of the present invention includes:

[0020] (1) Coating raw material fusion

[0021] Mix water, filler, and water-based bentonite, and ball mill for 2-3 hours. Add organic binder, silica sol, modified hexagonal boron nitride, dispersant, and defoamer, and stir and grind for 50-80 minutes.

[0022] (2) Substrate preparation

[0023] Spray a dilute nitric acid solution onto the substrate surface to be coated, clean it with ultrapure water, and then sandblast it.

[0024] (3) Coating forming

[0025] The mixture in (1) is sprayed onto the coating surface of the substrate in (2) at 230-250℃, and then treated at 400-420℃ for 3-5 minutes.

[0026] The mass fraction of the dilute nitric acid solution is 0.01-0.02%; the spraying amount is 8-10% of the substrate mass.

[0027] Compared with the prior art, the technical effects of the present invention are reflected in:

[0028] The durable non-stick coating of this invention uses a targeted combination of binders and fillers to achieve a high degree of coating density, better environmental resistance, and improved performance. In the preparation method of modified hexagonal boron nitride, potassium hydroxide and deionized water are mixed to form an alkaline solution. Ferric citrate is mixed with deionized water and added to the alkaline solution to form ferric hydroxide precipitate, which coats the surface of hexagonal boron nitride. Carrageenan is added to enhance the adhesion of the solution, resulting in better adhesion between the ferric hydroxide precipitate and hexagonal boron nitride, promoting contact between the two. After heating and drying, the dried product is placed in a calcination furnace. Under oxygen-filled conditions, the carrageenan is removed by calcination, and the ferric hydroxide decomposes to form ferric oxide. The temperature is then lowered to room temperature, carbon monoxide is introduced, and the product is heated for reduction, promoting the formation of iron-coated hexagonal boron nitride. Mixing with copper sulfate solution triggers iron-copper substitution, resulting in an iron-copper coating on the surface of the hexagonal boron nitride. Through the binding sites of copper and iron particles on the surface of the hexagonal boron nitride, the binding effect of hexagonal boron nitride in the coating is improved, promoting efficient bonding of boron nitride to materials, forming a neatly arranged and dense coating structure, improving the adhesion to the substrate, increasing environmental resistance, and enabling non-stick pans to maintain good performance during long-term use. Detailed Implementation

[0029] The technical solution of the present invention will be further defined below with reference to specific embodiments, but the scope of protection is not limited to the description made.

[0030] Example 1

[0031] A durable nonstick coating, by weight, is made of the following components:

[0032] The composition includes 8 parts organic binder, 3 parts silica sol, 6 parts filler, 1 part modified hexagonal boron nitride, 0.1 part water-based bentonite, 0.1 part dispersant, 0.1 part defoamer, and 5 parts water; the filler is 8 parts alumina, 1 part titanium dioxide, 5 parts magnesium oxide, and 2 parts zinc oxide; the dispersant is BYK-161; the defoamer is BYK-A530; and the organic binder is acrylate.

[0033] The method for preparing the modified hexagonal boron nitride is as follows:

[0034] (1) By mass, potassium hydroxide and deionized water are mixed evenly at a mass ratio of 2:3, sealed and left to stand for 11 min to obtain solution A;

[0035] Mix 1 part ferric citrate with 110 parts deionized water and stir for 4 minutes. Add 20 parts hexagonal boron nitride to the solution to obtain mixed solution B. Take the supernatant from solution A, take 2 parts and inject it into mixed solution B. Stir for 7 minutes, add 2 parts carrageenan and continue stirring for 30 minutes.

[0036] (2) Centrifuge the above-treated mixed solution B, rinse twice with ethanol, rinse once with deionized water, take the precipitate, heat and dry it, place the dried product in a roasting furnace, roast at 400℃ for 15 min under oxygen conditions; lower the temperature to room temperature, introduce carbon monoxide, heat at 700℃ for 20 min, and lower the temperature to room temperature.

[0037] The amount of carbon monoxide used is 10% of the mass of hexagonal boron nitride;

[0038] (3) Mix the powder obtained in the previous step with copper sulfate solution, heat the temperature to 33°C, stir for 20 minutes, filter, rinse the powder twice with deionized water, and dry.

[0039] The mass ratio of the powder to the copper sulfate solution is 1:50; the mass fraction of the copper sulfate solution is 5%.

[0040] The method for preparing the durable non-stick coating is as follows:

[0041] (1) Coating raw material fusion

[0042] Mix water, filler, and water-based bentonite, and ball mill for 2 hours. Add organic binder, silica sol, modified hexagonal boron nitride, dispersant, and defoamer, and stir and grind for 50 minutes.

[0043] (2) Substrate preparation

[0044] Spray a dilute nitric acid solution onto the substrate surface to be coated, clean it with ultrapure water, and then sandblast it.

[0045] The mass fraction of the dilute nitric acid solution is 0.01%; the spraying amount is 8% of the substrate mass.

[0046] (3) Coating forming

[0047] The mixture in (1) is sprayed onto the coating surface of the substrate in (2) at 230°C and then treated at 400°C for 3 minutes.

[0048] Example 2

[0049] A durable nonstick coating, by weight, is made of the following components:

[0050] The mixture comprises 10 parts organic binder, 5 parts silica sol, 9 parts filler, 2 parts modified hexagonal boron nitride, 0.3 parts water-based bentonite, 0.2 parts dispersant, 0.3 parts defoamer, and 7 parts water; the filler is composed of the following raw materials: 10 parts alumina, 2 parts titanium dioxide, 7 parts magnesium oxide, and 4 parts zinc oxide.

[0051] The dispersant is BYK-161; the defoamer is BYK-A530; the organic binder is acrylate;

[0052] The method for preparing the modified hexagonal boron nitride is as follows:

[0053] (1) By mass, potassium hydroxide and deionized water are mixed evenly at a mass ratio of 2:4, sealed and left to stand for 14 min to obtain solution A;

[0054] Mix 3 parts of ferric citrate with 130 parts of deionized water and stir for 7 minutes. Add 30 parts of hexagonal boron nitride to the solution to obtain mixed solution B. Take the supernatant from solution A, take 6 parts of it and inject it into mixed solution B. Stir for 10 minutes and add 3 parts of carrageenan and continue stirring for 50 minutes.

[0055] (2) Centrifuge the above-treated mixed solution B, rinse it 3 times with ethanol, then rinse it 2 times with deionized water, take the precipitate, heat and dry it, place the dried product in a roasting furnace, roast it at 430℃ for 20 min under oxygen conditions; lower the temperature to room temperature, introduce carbon monoxide, heat it at 710℃ for 30 min, and lower the temperature to room temperature.

[0056] The amount of carbon monoxide used is 15% of the mass of hexagonal boron nitride;

[0057] (3) Mix the powder obtained in the previous step with copper sulfate solution, heat the temperature to 35°C, stir for 30 minutes, filter, rinse the powder with deionized water 3 times, and dry.

[0058] The mass ratio of the powder to the copper sulfate solution is 1:50-67; the mass fraction of the copper sulfate solution is 6.4%.

[0059] The method for preparing the durable non-stick coating is as follows:

[0060] (1) Coating raw material fusion

[0061] Mix water, filler, and water-based bentonite, and ball mill for 3 hours. Add organic binder, silica sol, modified hexagonal boron nitride, dispersant, and defoamer, and stir and grind for 80 minutes.

[0062] (2) Substrate preparation

[0063] Spray a dilute nitric acid solution onto the substrate surface to be coated, clean it with ultrapure water, and then sandblast it.

[0064] The mass fraction of the dilute nitric acid solution is 0.02%; the spraying amount is 10% of the substrate mass.

[0065] (3) Coating forming

[0066] The mixture in (1) is sprayed onto the coating surface of the substrate in (2) at 250°C and then subjected to high-temperature treatment at 420°C for 5 minutes.

[0067] Example 3

[0068] A durable nonstick coating, by weight, is made of the following components:

[0069] The composition includes 9 parts organic binder, 4 parts silica sol, 7 parts filler, 2 parts modified hexagonal boron nitride, 0.1 parts water-based bentonite, 0.2 parts dispersant, 0.1 parts defoamer, and 7 parts water; the filler is: 10 parts alumina, 1 part titanium dioxide, 7 parts magnesium oxide, and 2 parts zinc oxide.

[0070] The dispersant is BYK-161; the defoamer is BYK-A530; the organic binder is acrylate;

[0071] The method for preparing the modified hexagonal boron nitride is as follows:

[0072] (1) By mass, potassium hydroxide and deionized water are mixed evenly at a mass ratio of 2:3, sealed and left to stand for 14 min to obtain solution A;

[0073] Mix 1 part ferric citrate with 130 parts deionized water and stir for 4 minutes. Add 30 parts hexagonal boron nitride to the solution to obtain mixed solution B. Take the supernatant from solution A, take 2 parts and inject it into mixed solution B. Stir for 7 minutes, add 3 parts carrageenan and continue stirring for 30 minutes.

[0074] (2) Centrifuge the above-treated mixed solution B, rinse it 3 times with ethanol, then rinse it 2 times with deionized water, take the precipitate, heat and dry it, place the dried product in a roasting furnace, roast it at 400℃ for 20 min under oxygen conditions; lower the temperature to room temperature, introduce carbon monoxide, heat it at 700℃ for 30 min, and lower the temperature to room temperature.

[0075] The amount of carbon monoxide used is 15% of the mass of hexagonal boron nitride;

[0076] (3) Mix the powder obtained in the previous step with copper sulfate solution, heat the temperature to 33°C, stir for 30 minutes, filter, rinse the powder twice with deionized water, and dry.

[0077] The mass ratio of the powder to the copper sulfate solution is 1:67; the mass fraction of the copper sulfate solution is 5%.

[0078] The method for preparing the durable non-stick coating is as follows:

[0079] (1) Coating raw material fusion

[0080] Mix water, filler, and water-based bentonite, and ball mill for 3 hours. Add organic binder, silica sol, modified hexagonal boron nitride, dispersant, and defoamer, and stir and grind for 50 minutes.

[0081] (2) Substrate preparation

[0082] Spray a dilute nitric acid solution onto the substrate surface to be coated, clean it with ultrapure water, and then sandblast it.

[0083] The mass fraction of the dilute nitric acid solution is 0.02%; the spraying amount is 8% of the substrate mass.

[0084] (3) Coating forming

[0085] The mixture in (1) is sprayed onto the coating surface of the substrate in (2) at 250°C and then treated at 400°C for 3 minutes.

[0086] Scale settings:

[0087] Comparative Example 1 The difference from Example 1 is that ferric citrate was not used when preparing the modified hexagonal boron nitride; Comparative Example 2 The difference from Example 1 is that copper sulfate was not used in the preparation of the modified hexagonal boron nitride; Comparative Example 3 The difference from Example 1 is that carrageenan was not used when preparing the modified hexagonal boron nitride; Comparative Example 4 The difference from Example 1 is that when preparing the modified hexagonal boron nitride, hexagonal boron nitride is replaced with cubic boron nitride.

[0088] Test case

[0089] Coatings were prepared according to Examples 1-3 and Comparative Examples 1-4. The adhesion between the coating and the substrate was tested using the WS-2005 automatic scratch tester. Each group of non-stick pans was heated to 350°C at a heating rate of 15°C / min, and the maximum number of repeated heating and cooling cycles under stable coating conditions was recorded. The salt spray resistance of the non-stick pans was tested according to the ASTM B-177 test method. Specific results are shown in the table below:

[0090] Binding force (N) Number of repeated temperature changes (times) Salt spray tolerance time (h) Example 1 26.89 6357.82 203 Example 2 27.44 6123.05 192 Example 3 28.06 6277.49 188 Comparative Example 1 21.67 5289.01 143 Comparative Example 2 22.34 5483.76 157 Comparative Example 3 24.73 5742.04 174 Comparative Example 4 23.06 5538.92 163

[0091] As can be seen from the table, the non-stick coating of the present invention has stronger adhesion, a higher number of repeated heating cycles, longer salt spray resistance, and better durability.

Claims

1. A durable non-stick pan coating, characterized in that, It is made from the following components in parts by weight: 8-10 parts organic binder, 3-5 parts silica sol, 6-9 parts filler, 1-2 parts modified hexagonal boron nitride, 0.1-0.3 parts water-based bentonite, 0.1-0.2 parts dispersant, 0.1-0.3 parts defoamer, and 5-7 parts water; The method for preparing the modified hexagonal boron nitride is as follows: (1) Mix potassium hydroxide and deionized water at a mass ratio of 2:3-4, seal and let stand for 11-14 min to obtain solution A; Mix 1-3 parts of ferric citrate with 110-130 parts of deionized water and stir for 4-7 minutes. Add 20-30 parts of hexagonal boron nitride to the solution to obtain mixed solution B. Take the supernatant from solution A, take 2-6 parts and inject it into mixed solution B. Stir for 7-10 minutes, add 2-3 parts of carrageenan and continue stirring for 30-50 minutes. (2) Centrifuge the above-treated mixed solution B, wash with ethanol 2-3 times, then wash with deionized water 1-2 times, take the precipitate, heat and dry it, place the dried product in a calcining furnace, and calcine at 400-430℃ for 15-20 min under oxygen conditions; lower the temperature to room temperature, introduce carbon monoxide, heat at 700-710℃ for 20-30 min, and lower the temperature to room temperature to obtain powder; Mix the powder obtained above with copper sulfate solution, heat the temperature to 33-35℃, stir for 20-30 minutes, filter, rinse the filter residue with deionized water 2-3 times, and dry.

2. The durable non-stick coating according to claim 1, characterized in that, The dispersant is BYK-161.

3. The durable non-stick coating according to claim 1, characterized in that, The defoamer is BYK-A530.

4. The durable non-stick coating according to claim 1, characterized in that, The organic adhesive is an acrylate.

5. The durable non-stick coating according to claim 1, characterized in that, The filler is composed of the following raw materials: 8-10 parts alumina, 1-2 parts titanium dioxide, 5-7 parts magnesium oxide, and 2-4 parts zinc oxide.

6. The durable non-stick coating according to claim 1, characterized in that, The amount of carbon monoxide used is 10-15% of the mass of hexagonal boron nitride.

7. The durable non-stick coating according to claim 1, characterized in that, The mass ratio of the powder to the copper sulfate solution is 1:50-67.

8. The durable non-stick coating according to claim 1, characterized in that, The copper sulfate solution has a mass fraction of 5-6.4%.

9. A method for preparing a durable non-stick pan coating as described in any one of claims 1-8, characterized in that, include; (1) Coating raw material fusion Mix water, filler, and water-based bentonite, and ball mill for 2-3 hours. Add organic binder, silica sol, modified hexagonal boron nitride, dispersant, and defoamer, and stir and grind for 50-80 minutes. (2) Substrate preparation Spray a dilute nitric acid solution onto the substrate surface to be coated, clean it with ultrapure water, and then sandblast it. (3) Coating forming The mixture in (1) is sprayed onto the coating surface of the substrate in (2) at 230-250℃, and then treated at 400-420℃ for 3-5 minutes.

10. The method for preparing the durable non-stick pan coating according to claim 9, characterized in that, The mass fraction of the dilute nitric acid solution is 0.01-0.02%; the spraying amount is 8-10% of the substrate mass.