Non-stick cookware and its manufacturing method

Abstract

This invention provides a non-stick cookware and a method for manufacturing the same. The non-stick cookware includes: a substrate; and a non-stick layer located on the surface of the substrate, wherein the non-stick layer comprises layered silicates and polysiloxane compounds. The non-stick cookware of this invention possesses excellent non-stick properties and durable non-stick performance.

Description

Technical Field

[0001] The present invention relates to the field of non-stick technology, and more specifically, to a non-stick cookware and its manufacturing method. Background Technology

[0002] During the cooking process, food can stick to cookware. Existing cookware mainly achieves this by spraying non-stick materials onto the inner surface of the pot. There are three main ways to achieve non-stick properties: 1) low surface energy; 2) micro-uneven structure to form a hydrophobic and oleophobic surface similar to a lotus leaf; 3) porous oil storage to form a stable oil film, using oil as an intermediary to achieve non-stick properties.

[0003] Existing non-stick cookware materials mainly include fluorinated coatings, ceramic coatings, and silicone resins. All three are applied by spraying to form a non-stick coating on the inner surface of the cookware to achieve a non-stick effect. Fluorinated coatings mainly include PTFE (polytetrafluoroethylene), PFOA (perfluorooctanoic acid), PFA (a copolymer of perfluoropropyl perfluorovinyl ether and polytetrafluoroethylene), FEP (perfluoroethylene propylene copolymer), and ETFE (ethylene-tetrafluoroethylene copolymer), etc. Their non-stick principle is mainly due to the extremely low surface free energy of the fluorinated polymers. Ceramic coatings are coatings with silicon-oxygen bonds and inorganic silicon as the main components. Their non-stick principle is mainly due to the formation of nanostructures on the surface of the cookware, thus achieving a non-stick effect. Silicone resins mainly utilize their low surface energy to achieve a non-stick effect.

[0004] While all three types of coatings offer non-stick properties, they all have significant drawbacks. Fluoropolymer coatings are not wear-resistant; they cannot be used with metal spatulas for cooking, nor can they be cleaned with steel wool or scouring pads. They decompose at high temperatures, producing harmful substances, and their non-stick properties decrease after wear. Ceramic coatings are less effective at non-sticking than fluorine-based coatings, and their durability is also poor; the coating typically peels off after 3-6 months of use. Silicone coatings are also less effective at non-sticking than fluorine-based coatings; they tend to yellow or gray after exposure to high temperatures or open flames, and their hardness decreases at high temperatures, easily leading to a "re-sticking" phenomenon.

[0005] The information disclosed in this background section is only intended to enhance the understanding of the background of the inventive concept. Therefore, the above information may contain information that does not constitute prior art known to those skilled in the art in this country. Summary of the Invention

[0006] In order to solve one or more of the above-mentioned problems in the prior art, the present invention provides a non-stick cookware and a method for manufacturing the same.

[0007] An exemplary embodiment of the present invention provides a non-stick cookware comprising: a substrate; and a non-stick layer located on the surface of the substrate, wherein the non-stick layer comprises layered silicates and polysiloxane compounds.

[0008] According to exemplary embodiments of the present invention, the polysiloxane compound includes at least one of polymethylsiloxane and polydimethylsiloxane.

[0009] According to an exemplary embodiment of the present invention, the layered silicate includes at least one of pyrophyllite, kaolinite, muscovite, glauconite, prehnite, chlorite, illite, lepidolite, hydroxyapatite, biotite, phlogopite, vermiculite, montmorillonite, talc, and serpentine.

[0010] According to an exemplary embodiment of the present invention, the non-stick cookware further includes a transition layer located between the substrate and the non-stick layer.

[0011] An exemplary embodiment of the present invention provides a method for manufacturing a non-stick cookware, the method comprising the steps of: preparing a substrate; and forming a non-stick layer on the surface of the substrate, wherein the non-stick layer comprises layered silicates and polysiloxane compounds.

[0012] According to an exemplary embodiment of the present invention, the step of forming a non-stick layer includes: applying layered silicate to the surface of a substrate using a layering process to form an initial non-stick layer comprising layered silicate on the surface of the substrate; and filling the initial non-stick layer with a polysiloxane compound.

[0013] According to an exemplary embodiment of the present invention, the method further includes a step of pretreating the layered silicate before forming the non-stick layer, the pretreating step including: acid washing of the layered silicate; and / or alkaline washing of the layered silicate.

[0014] According to an exemplary embodiment of the present invention, the pretreatment step further includes: ball milling the layered silicate prior to acid washing or alkali washing.

[0015] According to an exemplary embodiment of the present invention, the filling step includes: contacting the initial non-stick layer with a solution of a polysiloxane compound to allow the polysiloxane compound to enter the interlayer structure of the layered silicate in the initial non-stick layer.

[0016] According to an exemplary embodiment of the present invention, the filling step further includes sintering the initial non-stick layer filled with polysiloxane compounds at a temperature of 280°C to 300°C.

[0017] According to an exemplary embodiment of the present invention, the step of preparing a substrate includes: shot peening the surface of the substrate; and sandblasting the surface of the shot-peened substrate.

[0018] According to an exemplary embodiment of the invention, the method further includes the step of forming a transition layer on the surface of the substrate prior to forming the non-adhesive layer. Detailed Implementation

[0019] Exemplary embodiments based on the inventive concept will now be described in detail to explain the present invention. However, the invention may be embodied in many different forms and should not be construed as being limited to the exemplary embodiments set forth herein. These embodiments are provided so that the disclosure of the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0020] As mentioned above, in the existing technology, various non-stick coatings all have certain defects, such as poor wear resistance, which leads to a decrease in non-stick properties after wear and easy release of harmful substances; poor initial non-stick properties; or poor long-term non-stick properties and short service life.

[0021] Therefore, in order to solve the technical problems including at least the above-mentioned issues, the present invention provides a non-stick cookware and a method for manufacturing the same.

[0022] The non-stick cookware based on the inventive concept will be described in detail below.

[0023] The non-stick cookware of exemplary embodiments of the present invention can be used in various utensils or devices that require non-stick treatment. For example, the non-stick cookware of exemplary embodiments of the present invention can be used in various kitchen utensils such as pots, pans, baking trays, etc., and the present invention is not limited thereto. Hereinafter, a non-stick cookware of exemplary embodiments of the present invention will be described using a pot as an example.

[0024] A non-stick cookware according to an exemplary embodiment of the present invention may include: a substrate and a non-stick layer formed on the surface of the substrate.

[0025] In exemplary embodiments of the present invention, the substrate may include any suitable material requiring a non-stick treatment. For example, the substrate may include iron, aluminum, stainless steel, titanium, and their alloys, but the present invention is not limited thereto. Furthermore, a substrate with accommodating space can be provided using a blank layer of a certain shape formed from at least one of the aforementioned materials. Here, the substrate may have an inner surface and an outer surface, the inner surface for applying the non-stick layer, while the outer surface may optionally be coated with a magnetic layer, a rust-preventive layer, etc.

[0026] In an exemplary embodiment of the present invention, the non-stick layer may be formed on the surface of the substrate. It is understood that the non-stick layer may be located on at least a portion of the inner surface of the substrate (e.g., a portion of the inner surface adjacent to the contained food or the entire inner surface), that is, the non-stick layer may be located only on the inner surface of the substrate, or it may be located on both the inner and outer surfaces of the substrate.

[0027] The non-stick layer may comprise layered silicates and polysiloxane compounds. In an exemplary embodiment of the present invention, the main body of the non-stick layer may be composed of layered silicates, that is, the layered silicates may form the "skeleton" of the non-stick layer. The polysiloxane compounds may be located in various vacancy spaces of the layered silicates, such as in the pores of the layered silicates themselves, in the gaps between adjacent layers in the lateral direction, and between adjacent layers in the longitudinal direction.

[0028] Layered silicates are natural minerals, with each naturally occurring layer approximately 1 nm thick, bonded together by van der Waals forces. Due to their layered structure, when layered silicates are applied to a substrate using processes such as thermal spraying, a dense coating with a microscopically layered structure can be formed. Compared to coatings formed by thermally spraying metallic or non-metallic particles in the prior art, coatings formed from layered silicates can have smaller pores, thus providing better barrier properties and more effectively protecting the substrate or the transition layer described below from external substances. Therefore, in exemplary embodiments of the present invention, when a transition layer is formed between the substrate and the non-adhesive layer, the aforementioned structural characteristics of layered silicates allow the transition layer to be formed with a relatively thin thickness.

[0029] Furthermore, layered silicates can have a layered structure similar to scales, and the area of ​​a single "scale" can be as small as 1 μm. 2 ~5μm 2 Within a certain range. If the area of ​​a single scale is too small, the strength of the final non-stick layer will be reduced; if the area of ​​a single scale is too large, the non-stick properties of the final non-stick layer may be poor.

[0030] Furthermore, because the non-stick layer formed by thermal spraying of silicates has a layered structure rather than a granular structure, its wear resistance is superior. In other words, the non-stick layer conceived in this invention has more durable non-stick properties.

[0031] In exemplary embodiments of the present invention, layered silicates may include at least one selected from pyrophyllite, kaolinite, muscovite, glauconite, prehnite, chlorite, illite, lepidolite, lithium mica, hydroxyapatite, biotite, phlogopite, vermiculite, montmorillonite, talc, and serpentine, and examples of their chemical formulas may be represented, but are not limited to, the following:

[0032] Serpentine Mg6[Si4O 10 ](OH)8;

[0033] Kaolinite Al4[Si4O 10 ](OH)8;

[0034] Talc Mg3[Si4O 10 (OH)2;

[0035] Pyrophyllite Al2[Si4O 10 (OH)2;

[0036] Montmorillonite (Na,Ca) 0.33 (Al,Mg,Fe)2[(Si,Al)4O 10 (OH)2·nH2O;

[0037] Vermiculite [(Mg,Ca)] 0.5 [(H₂O)₄](Mg,Fe,Al)₃[(Si,Al)₄O 10 (OH)2;

[0038] Phlogopite KMg3[Si3AlO 10 (OH,F)2;

[0039] Biotite K(Mg,Fe)3[Si3AlO 10 (OH,F)2;

[0040] Hydroxyferric mica KFe3[Si3AlO 10 (OH,F)2;

[0041] Muscovite KAl2[Si3AlO 10 (OH,F)2;

[0042] Lithium mica K(Li,Al) 2.5-3 [Si 3.5-3 Al 0.5-1 O 10 (OH,F)2;

[0043] Lithium iron phosphate mica K(Li,Fe,Al)3[Si 3-3.5 Al 1-0.5 O 10 (OH,F)2;

[0044] illite (K,H3O)(Al,Mg,Fe)2[(Si,Al)4O 10 (OH)2;

[0045] Chlorite(Mg,Al,Fe)6[(Si,Al)4O10 ](OH)8;

[0046] Prehnite Ca2Al[Si3AlO 10 (OH)2;

[0047] Glauconite K(Fe,Mg,Al)2[Si4O 10 ](OH)2.

[0048] Polysiloxane compounds have a main chain structure formed by Si-O-Si and side chains containing organic groups. Since their main chain is a multi-polyhedral structure formed by Si and O, which is similar to the lattice structure of layered silicates, the Si and O in polysiloxane compounds can bond with the Si and O in layered silicates, thus stably binding onto the layered silicates.

[0049] In addition, the side chains containing organic groups in polysiloxane compounds have good oleophilic and hydrophobic properties. Therefore, non-stick layers containing layered silicates and polysiloxane compounds can have good non-stick properties.

[0050] In this invention, in order to increase the amount of polysiloxane compounds formed in the layered silicate and thus give the non-stick layer better non-stick properties, the layered silicate can be pretreated, which will be described in more detail below.

[0051] The thickness of the non-stick layer can be in the range of 20μm to 60μm, and can be substantially uniform or vary depending on the specific location on the substrate.

[0052] According to a preferred embodiment, a transition layer may be further included between the substrate and the non-stick layer. The transition layer may be located at least on the inner surface of the substrate; that is, the transition layer may be located only on the inner surface of the substrate, or it may be located on both the inner and outer surfaces of the substrate. For example, when the non-stick cookware of the present invention is used for cookware, the transition layer may be located only on the inner surface of the substrate; when the non-stick cookware of the present invention is used for spatulas, spoons, etc., the transition layer may be located on both the inner and outer surfaces of the substrate.

[0053] The transition layer can be formed through, but is not limited to, thermal spraying processes, and therefore can possess certain hardness, wear resistance, and corrosion resistance. The material of the transition layer can be a metal and / or a metal alloy, and the corresponding transition layer can be a thermally sprayed metal layer and / or a thermally sprayed metal alloy layer. Further, the transition layer can be at least one of the following: thermally sprayed aluminum layer, thermally sprayed aluminum alloy layer, thermally sprayed zinc layer, thermally sprayed zinc alloy layer, thermally sprayed titanium layer, thermally sprayed titanium alloy layer, thermally sprayed copper layer, thermally sprayed copper alloy layer, thermally sprayed nickel layer, thermally sprayed nickel alloy layer, and thermally sprayed stainless steel layer.

[0054] The thickness of the transition layer can be in the range of 10 μm to 20 μm. The transition layer can have a substantially uniform thickness, or it can have a varying thickness depending on its specific location on the substrate. For example, when the non-stick cookware of the present invention is used in a pot, the transition layer can have a relatively thicker thickness at the location corresponding to the bottom of the pot, and a relatively thinner thickness at the location corresponding to the rim of the pot.

[0055] The non-stick cookware conceived according to the present invention includes a substrate, an optional transition layer, and a non-stick layer. The non-stick layer includes layered silicates and polysiloxane compounds bonded to the layered silicates, thereby enabling the non-stick cookware to have excellent non-stick properties, and allowing the transition layer to be formed to have a relatively thin thickness.

[0056] In the following text, a method for manufacturing a non-stick cookware according to the present invention will be described, and redundant descriptions that are the same as or similar to those above will be omitted.

[0057] A method for manufacturing a non-stick cookware according to the present invention includes: preparing a substrate; and forming a non-stick layer on the surface of the substrate.

[0058] First, prepare a substrate, which can include any suitable material that requires a non-stick treatment. For example, the substrate can include iron, aluminum, stainless steel, titanium, and their alloys, but the inventive concept is not limited thereto.

[0059] In an exemplary embodiment of the present invention, the surface of the substrate can be shot-peened to form a density of 2 to 6 particles / cm² on the surface of the substrate. 2 The diameter of each recess can be in the range of 1.0mm to 1.5mm, and the depth can be in the range of 0.3mm to 0.7mm.

[0060] The surface of the shot-peened substrate can then be sandblasted to give it a certain degree of micro-roughness, thereby improving the adhesion between the subsequent layers formed on the substrate and the substrate itself, and also removing dirt from the substrate surface. However, the exemplary embodiments are not limited thereto; that is, the shot-peening and sandblasting steps can be omitted.

[0061] After providing the substrate, a transition layer can preferably be formed on the surface of the substrate, whether it has undergone shot peening and sandblasting or not. For example, a thermal spraying process can be used to form the transition layer on the substrate surface. The specific process parameters for the thermal spraying process are as follows: current 250A~350A; voltage 30V~60V; main gas (argon) flow rate 1500L / h~2000L / h; hydrogen flow rate 30L / h~50L / h; powder feeding gas flow rate 20L / h~40L / h; powder feeding rate 20g / min~50g / min; spraying distance (distance between nozzle and workpiece) 15cm~25cm; spraying angle 30°~80°; workpiece temperature 10℃~40℃.

[0062] In exemplary embodiments of the present invention, a transition layer may be formed on the inner surface of the substrate, or it may be formed simultaneously on both the inner and outer surfaces of the substrate. Furthermore, metal and / or metal alloy powders may be used as thermal spraying materials to form the transition layer. Accordingly, the transition layer may be a thermally sprayed metal layer and / or a thermally sprayed metal alloy layer. For example, the transition layer may be at least one of the following: thermally sprayed aluminum layer, thermally sprayed aluminum alloy layer, thermally sprayed zinc layer, thermally sprayed zinc alloy layer, thermally sprayed titanium layer, thermally sprayed titanium alloy layer, thermally sprayed copper layer, thermally sprayed copper alloy layer, thermally sprayed nickel layer, thermally sprayed nickel alloy layer, and thermally sprayed stainless steel layer.

[0063] The particle size of the thermal spray particles forming the transition layer can be in the range of 20 μm to 35 μm. The transition layer can be formed to have a thickness in the range of 10 μm to 20 μm. The transition layer can have a substantially uniform thickness, or it can have a varying thickness depending on its specific location on the substrate. For example, a transition layer with varying thickness can be achieved by adjusting various process parameters during the thermal spraying process. However, the exemplary embodiments are not limited thereto; that is, the step of forming the transition layer can be omitted.

[0064] Next, a non-stick layer can be formed on the substrate that has been shot-peened and sandblasted or has not been shot-peened or sandblasted, or on the surface of the transition layer.

[0065] The steps for forming the non-stick layer will be described below.

[0066] First, prepare suitable layered silicate powder. Layered silicates can include at least one of the following as described above: pyrophyllite, kaolinite, muscovite, glauconite, prehnite, chlorite, illite, lepidolite, lithium mica, hydroxyapatite, biotite, phlogopite, vermiculite, montmorillonite, talc, and serpentine. The particle size of the powder can be in the range of 20 μm to 100 μm.

[0067] The layered silicate powder can then be ball-milled (e.g., wet ball milling). For example, the layered silicate powder can be mixed with a solvent (e.g., water or ethanol) in a 1:1 ratio and then rotated at 20 rpm for 2 to 4 hours. Ball milling causes the layered silicate powder to rub against each other, thereby increasing the porosity of the layered silicate surface and providing better reaction conditions for subsequent acid and alkali washing processes. However, the ball milling step can be omitted.

[0068] Next, the layered silicate powder, whether ball-milled or not, can be acid-washed. For example, acid washing can be performed as follows: Place the ball-milled or un-ball-milled layered silicate powder into a 10%–30% hydrochloric acid solution, where the volume of the hydrochloric acid solution is 3–5 times the volume of the layered silicate powder; let the mixture stand at 50°C–70°C for 1–4 hours; then filter the mixture and wash the layered silicate powder with water; finally, dry the layered silicate powder at 120°C–150°C. Acid washing removes Fe from the layered silicate.

[0069] Then, the acid-washed layered silicate can be subjected to alkaline washing. For example, this can be done by placing the acid-washed layered silicate powder into a 1 mol / L to 2 mol / L sodium hydroxide solution, where the volume of the sodium hydroxide solution is 3 to 5 times the volume of the layered silicate. The mixture is left to stand at room temperature for 1 to 4 hours; then the mixture is filtered, and the layered silicate powder is washed with water; finally, the layered silicate powder is dried at 120°C to 150°C. Al can be removed from the layered silicate through alkaline washing.

[0070] The above-described acid and alkali washing steps can remove Fe-containing and Al-containing compounds (e.g., mainly Fe-containing and Al-containing compounds between the layers of layered silicates) from the layered silicates, thereby increasing the vacancy space within the layered silicates. However, exemplary embodiments are not limited thereto, and at least one of the acid and alkali washing steps may be omitted.

[0071] Furthermore, after the layered silicate powder has been acid-washed and / or alkali-washed, it can be subjected to a secondary ball milling. For example, the secondary ball milling can be performed according to the process parameters described above. This can further increase the porosity of the layered silicate.

[0072] The next step involves applying layered silicate powder onto the surface of the substrate or transition layer using a process such as thermal spraying to form an initial non-stick layer. For example, the specific process parameters for thermal spraying are as follows: current 450A–600A; voltage 50V–80V; main gas (argon) flow rate 1000L / h–2000L / h; hydrogen flow rate 50L / h–100L / h; powder feed gas flow rate 20L / h–40L / h; powder feed rate 20g / min–50g / min; spraying distance (distance between nozzle and workpiece) 15cm–25cm; spraying angle 30°–80°; workpiece temperature 10℃–40℃. This forms an initial non-stick layer with a thickness ranging from 20μm to 60μm.

[0073] In an exemplary embodiment of the present invention, an initial non-stick layer may be formed on the inner surface of the substrate, or an initial non-stick layer may be formed simultaneously on both the inner and outer surfaces of the substrate.

[0074] In thermal spraying processes, power depends on the product of current and voltage. When the power is too low, the layered silicates are difficult to melt, preventing coating formation; when the power is too high, the layered structure of the silicates is destroyed, preventing the formation of a coating with a microscopic layered structure. Therefore, compared to existing technologies, the non-stick cookware manufacturing method of this invention uses a current value of 450A to 600A to form an initial non-stick layer with a microscopic layered structure on the transition layer.

[0075] In exemplary embodiments of the present invention, the initial non-stick layer can be formed to have a thickness in the range of 20 μm to 60 μm. The initial non-stick layer can have a substantially uniform thickness, or it can have a varying thickness depending on its specific location on the substrate. For example, an initial non-stick layer with a varying thickness can be achieved by adjusting various process parameters during the process of forming the non-stick layer.

[0076] After forming the initial non-stick layer on the substrate or transition layer, the surface of the initial non-stick layer can be treated to make its surface roughness Ra ≤ 3 μm. For example, the surface of the initial non-stick layer can be sanded to make its surface roughness Ra ≤ 3 μm.

[0077] The next step can be to fill the initial non-stick layer with a polysiloxane. For example, polysiloxane filling can include contacting the initial non-stick layer with a solution of a polysiloxane compound, allowing the polysiloxane compound to enter the interlayer spaces of the layered silicates in the initial non-stick layer. Furthermore, polysiloxane filling can also include sintering the initial non-stick layer with the adsorbed polysiloxane compound at a temperature of 280°C to 300°C.

[0078] In an exemplary embodiment of the present invention, a solution containing at least one of polymethylsiloxane and polydimethylsiloxane (e.g., propylene glycol methyl ether ethyl ester as solvent) can be uniformly coated onto the surface of the initial non-stick layer treated by the above-described process steps. Then, the resulting substrate is placed at 80°C to 120°C for 3 to 10 minutes to allow the layered silicates in the initial non-stick layer to fully adsorb the polymethylsiloxane and / or polydimethylsiloxane. Excess solution on the surface of the initial non-stick layer is then removed. The substrate is then sintered at 280°C to 300°C for 4 to 6 minutes.

[0079] Through the above steps, at least one of polymethylsiloxane and polydimethylsiloxane can be accommodated in the vacancies within the layered silicate and bonded to the layered silicate to form a non-stick layer comprising the layered silicate and at least one of polymethylsiloxane and polydimethylsiloxane.

[0080] The non-stick cookware manufacturing method of the present invention can produce non-stick cookware with better non-stick properties and improved strength, and can reduce the thickness of the anti-corrosion coating (i.e., the transition layer and the non-stick layer) in the non-stick cookware.

[0081] The manufacturing method of the non-stick cookware according to the present invention will now be described with reference to specific embodiments.

[0082] Example 1

[0083] Prepare a base material for cookware made of wrought iron.

[0084] Next, aluminum alloy powder with an average particle size of 28 μm is sprayed onto the inner surface of the substrate using a thermal spraying process to form a thermally sprayed aluminum alloy layer as a transition layer. Specific process parameters are as follows: current 300A; voltage 45V; main gas (argon) flow rate 1750 L / h; hydrogen flow rate 40 L / h; powder feed gas flow rate 30 L / h; powder feed rate 35 g / min; spraying distance (nozzle to workpiece) 20 cm; spraying angle 55°; workpiece temperature 25°C. This forms a transition layer with a thickness of approximately 15 μm.

[0085] Pyrophyllite powder with an average particle size of 60 μm was selected and sprayed onto the surface of the transition layer using a thermal spraying process to form an initial non-stick layer. Specific process parameters were as follows: current 525A; voltage 65V; main gas (argon) flow rate 1500 L / h; hydrogen flow rate 75 L / h; powder feed gas flow rate 30 L / h; powder feed rate 35 g / min; spraying distance (nozzle to workpiece) 20 cm; spraying angle 55°; workpiece temperature 25℃. This resulted in an initial non-stick layer with a thickness of approximately 40 μm.

[0086] A propylene glycol methyl ether ethyl solution of polydimethylsiloxane was uniformly coated onto the surface of the initial non-stick layer treated in the above steps. Then, the substrate with the transition layer and the initial non-stick layer was placed at ℃ for 7 minutes to allow the layered silicates in the initial non-stick layer to fully adsorb the polymethylsiloxane and polydimethylsiloxane. Next, excess solution was removed from the surface of the initial non-stick layer. The substrate was then sintered at 290℃ for 5 minutes. A non-stick pan comprising the substrate, transition layer, and non-stick layer was obtained.

[0087] Example 2

[0088] The difference from Example 1 is that it further includes the steps of shot peening and sandblasting the surface of the substrate. Shot peening is performed according to the following process parameters to form a surface with a density of approximately 4 particles / cm². 2 The recesses have an average diameter of 1.25 mm and an average depth of 0.5 mm. Then, the surface of the shot-peened substrate is sandblasted.

[0089] Example 3

[0090] The difference from Example 2 is that it also includes the steps of acid washing and alkali washing of pyrophyllite powder.

[0091] Layered silicate powder was placed in a 20% hydrochloric acid solution, the volume of which was four times the volume of the layered silicate powder. The mixture was left to stand at 60°C for 2.5 hours. The mixture was then filtered, and the layered silicate powder was washed with water. The layered silicate powder was then dried at 135°C.

[0092] Then, the acid-washed layered silicate powder was placed in a 1.5 mol / L sodium hydroxide solution, the volume of which was four times the volume of the layered silicate powder. The mixture was left to stand at room temperature for 2.5 hours; then the mixture was filtered, the layered silicate powder was washed with water, and the layered silicate powder was dried at 135°C.

[0093] Example 4

[0094] The difference from Example 3 is that the pyrophyllite powder was wet ball-milled before acid washing and alkali washing. The pyrophyllite powder was mixed with water in a 1:1 ratio and rotated at 20 r / min for 3 hours.

[0095] Example 5

[0096] The difference from Example 4 is that after acid washing and alkali washing, the pyrophyllite powder is also wet ball milled, with the pyrophyllite powder and water mixed in a 1:1 ratio and rotated at 20 r / min for 3 hours.

[0097] Example 6

[0098] The difference from Example 5 is that the current value of the thermally sprayed pyrophyllite powder is 450A.

[0099] Example 7

[0100] The difference from Example 5 is that the current value of the thermally sprayed pyrophyllite powder is 600A.

[0101] Example 8

[0102] The difference from Example 5 is that the above-mentioned substrate was sintered at 280°C for 5 minutes.

[0103] Example 9

[0104] The difference from Example 5 is that the above-mentioned substrate was sintered at 300°C for 5 minutes.

[0105] Example 10

[0106] The difference from Example 5 is that the thickness of the initial non-stick layer formed is 20 μm.

[0107] Example 11

[0108] The difference from Example 5 is that the thickness of the initial non-stick layer formed is 60 μm.

[0109] Example 12

[0110] The difference from Example 5 is that kaolinite is used as a layered silicate and thermally sprayed onto the surface of the transition layer to form an initial non-stick layer.

[0111] Example 13

[0112] The difference from Example 5 is that montmorillonite is used as a layered silicate for thermal spraying on the surface of the transition layer to form an initial non-stick layer.

[0113] Example 14

[0114] The difference from Example 1 is that the transition layer is omitted.

[0115] Comparative Example 1

[0116] The difference from Example 1 is that a non-stick layer is formed using a fluoropolymer coating including PTFE.

[0117] Comparative Example 2

[0118] The difference from Example 1 is that a ceramic coating is used to form a non-stick layer.

[0119] Comparative Example 3

[0120] The difference from Example 1 is that a non-stick layer is formed using silicone resin.

[0121] The coating strength, initial non-stickness and durable non-stickness of the cookware of Examples 1 to 13 and Comparative Examples 1 to 3 were tested, and the results are shown in Table 1.

[0122] Coating strength test

[0123] Use a 500g solid stainless steel ball and drop it every 5cm. Record the height at which the stainless steel ball impacts the inner surface of the pot. The higher the height, the stronger the coating. The height should not be less than 30cm.

[0124] Initial non-stickiness test

[0125] The non-stickiness test of fried eggs was conducted in accordance with GB / T 32095.2-2015. This method is an initial non-stickiness test, which is divided into three levels: I, II, and III. Level I has the best non-stickiness, and Level III has the worst non-stickiness.

[0126] Durable non-stick test

[0127] Referring to the abrasion resistance test method in GB / T32095, perform the national standard fried egg test every 1000 times until the coating is worn through and the bottom is exposed, or until the national standard fried egg test reaches level III after 2000 consecutive tests. Record the number of abrasion resistance tests. The more tests, the better the long-lasting non-stick properties.

[0128] Table 1

[0129] plan Coating strength (cm) Initial non-stickiness Long-lasting non-stick properties (per use) Example 1 60 Ⅰ 7000 Example 2 90 Ⅰ 7000 Example 3 90 Ⅰ 12000 Example 4 90 Ⅰ 15000 Example 5 90 Ⅰ 18000 Example 6 95 Ⅰ 15000 Example 7 80 Ⅰ 15000 Example 8 80 Ⅰ 17000 Example 9 80 Ⅰ 17000 Example 10 90 Ⅰ 14000 Example 11 60 Ⅰ 21000 Example 12 95 Ⅰ 17000 Example 13 85 Ⅰ 19000 Example 14 40 Ⅰ 18000 Comparative Example 1 Cannot withstand iron shovel Ⅰ 7000 Comparative Example 2 50 Ⅰ 1000 Comparative Example 3 50 Ⅰ 1000

[0130] As can be seen from Table 1, the non-stick pans prepared according to Examples 1 to 13 of the present invention have better coating strength compared to Comparative Example 1. Compared to Comparative Examples 2 and 3, the non-stick pans prepared according to Examples 1 to 13 of the present invention have better durable non-stick properties.

[0131] Comparing Examples 6 and 7 with Example 5, it can be seen that: the higher the current, the denser the coating and the better the wear resistance, but the coating strength will decrease. In addition, since the coating adsorbs less non-stick material, the long-lasting non-stick properties will also decrease. The lower the current, the looser the coating. Although more non-stick material is adsorbed, the wear resistance is poor, and therefore the long-lasting non-stick properties will also decrease.

[0132] Comparing Examples 8 and 9 with Example 5, it can be seen that: when the temperature is higher, the sintered coating becomes denser and the non-stick properties decrease; when the temperature is lower, the sintered coating is relatively less dense and the wear resistance decreases. Therefore, the non-stick pans of Examples 8 and 9 have lower durable non-stick properties than those of Example 5.

[0133] Comparing Examples 10 and 11 with Example 5, it can be seen that as the coating thickness increases, the durable non-stickiness improves, but the coating strength decreases.

[0134] Furthermore, the non-stick pan prepared in Example 3 exhibits superior long-lasting non-stick properties compared to the non-stick pan prepared in Example 1. This demonstrates that acid and alkali washing of layered silicates can improve the long-lasting non-stick performance of non-stick pans.

[0135] Compared with Example 3, the non-stick pans prepared in Examples 4 and 5 showed further improvement in their long-lasting non-stick properties, indicating that ball milling of layered silicates can also improve the long-lasting non-stick performance of non-stick pans.

[0136] Furthermore, as can be seen from Examples 12 and 13, using kaolinite and montmorillonite as layered silicates to form a thermal spray coating can give non-stick pans good coating strength and long-lasting non-stick properties.

[0137] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications or equivalent substitutions made to the present invention without departing from the spirit and scope thereof should be covered within the protection scope of the claims of the present invention.

Claims

1. A non-stick cookware, characterized in that, The non-stick cookware includes: Substrate; and A non-stick layer is located on the surface of the substrate. The non-stick layer comprises an initial non-stick layer and a polysiloxane compound. The initial non-stick layer is a layered silicate layer with a layered structure formed by laying layered silicates, and the layered silicate layer serves as the skeleton of the non-stick layer. The polysiloxane compound has oleophilic and hydrophobic organic groups that fill the spaces between the layered structures of the layered silicate layer.

2. The non-stick cookware according to claim 1, characterized in that, The polysiloxane compounds include at least one of polymethylsiloxane and polydimethylsiloxane; and / or, the layered silicates include at least one of pyrophyllite, kaolinite, muscovite, glauconite, prehnite, chlorite, illite, lepidolite, lithium mica, hydroxyapatite, biotite, phlogopite, vermiculite, montmorillonite, talc, and serpentine.

3. The non-stick cookware according to claim 1, characterized in that, The layered structure includes gaps between adjacent layers in the lateral direction and between adjacent layers in the longitudinal direction; and / or, the polysiloxane compound also fills the pores of the layered silicate itself; and / or, the thickness of the non-stick layer is 20 micrometers to 60 micrometers.

4. The non-stick cookware according to claim 1, characterized in that, The non-stick cookware also includes: A transition layer is located between the substrate and the non-adhesive layer.

5. A method for manufacturing a non-stick cookware, characterized in that, The manufacturing method includes the following steps: Prepare the substrate; and A layering process is used to lay layered silicates on the surface of the substrate to form a layered silicate layer with a layered structure as the initial non-stick layer. A non-stick layer is obtained by filling the initial non-stick layer with a polysiloxane compound having oleophilic and hydrophobic organic groups.

6. The manufacturing method according to claim 5, characterized in that, The manufacturing method further includes a pretreatment step of the layered silicate prior to forming the non-stick layer, the pretreatment step comprising: Acid washing of layered silicates; and / or The layered silicate was washed with alkali.

7. The manufacturing method according to claim 6, characterized in that, The preprocessing steps also include: The layered silicates are ball-milled before acid or alkali washing.

8. The manufacturing method according to claim 5, characterized in that, The filling step includes: The initial non-stick layer is brought into contact with a solution of polysiloxane compound so that the polysiloxane compound enters the layered silicate structure within the initial non-stick layer.

9. The manufacturing method according to claim 5, characterized in that, The filling step further includes: The initial non-stick layer filled with polysiloxane compounds was sintered at 280℃~300℃.

10. The manufacturing method according to claim 5, characterized in that, The steps for preparing the substrate include: The surface of the substrate is shot-peened; and The surface of the substrate that has undergone shot peening is then subjected to sandblasting.

11. The manufacturing method according to claim 5, characterized in that, The manufacturing method further includes the step of forming a transition layer on the surface of the substrate before forming the non-stick layer.