CN115044853B

CN115044853B - Amorphous non-stick material and amorphous non-stick coating for cookware

Info

Publication number: CN115044853B
Application number: CN202210758529.4A
Authority: CN
Inventors: 张明; 李超; 瞿义生; 袁华庭
Original assignee: Wuhan Supor Cookware Co Ltd
Current assignee: Wuhan Supor Cookware Co Ltd
Priority date: 2022-06-29
Filing date: 2022-06-29
Publication date: 2023-09-15
Anticipated expiration: 2042-06-29
Also published as: CN115044853A

Abstract

Amorphous non-stick materials and non-stick coatings for cookware are provided. The amorphous non-stick coating comprises, based on the total weight of the amorphous non-stick coating: titanium dioxide is more than or equal to 40wt% and less than or equal to 65wt%; iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 55wt%; calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less; phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; and 0.ltoreq.carbon and silicon.ltoreq.5wt%, wherein titanium dioxide exists as a titanium phase in the amorphous non-stick coating, iron oxide and ferrous oxide coexist as an iron phase in the amorphous non-stick coating, and titanium dioxide as a titanium phase has an anatase type structure. Such amorphous non-stick coatings can have low surface energy and sufficient hardness.

Description

Amorphous non-stick material and amorphous non-stick coating for cookware

Technical Field

The present inventive concept relates to a non-stick material and a non-stick coating for cookware, and more particularly, to a non-stick material and a non-stick coating having amorphous characteristics for cookware.

Background

Since the advent of non-stick cookware such as non-stick cookware, the cooking experience of people has been significantly improved. The existing non-stick cookware generally realizes the non-stick function by spraying a fluororesin coating on the surface of a metal substrate. The formed fluororesin non-stick coating has good non-stick properties, but also has a problem of short life due to the properties of the fluororesin itself. For example, a fluororesin as a polymer material is insufficient in hardness characteristics and high temperature resistance. Because of insufficient hardness, the surface of the fluororesin non-stick coating is easily scratched when hard foods (such as shells, etc.) are cooked (e.g., stir-fried). Because of the insufficient high temperature resistance, the fluororesin non-stick coating cannot be used at a high temperature of 260 ℃ or higher for a long period of time, however, the temperature is generally difficult to control in actual cooking. These all lead to the problem of short life of the fluororesin non-stick coating.

In addition, for the problem of intolerance to high temperature of the fluororesin nonstick coating, the temperature in the pot can be reduced by thickening the thickness of the pot body, but the problem not only causes the food material to be difficult to cook, the cooking experience is poor, but also the manufacturing cost of the pot body can be increased.

Disclosure of Invention

Embodiments of the inventive concept provide a non-stick material having amorphous characteristics, and a non-stick coating formed of the non-stick material has good non-stick properties, improved durability, and improved hardness.

Embodiments of the inventive concept also provide a non-stick coating formed of a non-stick material having amorphous characteristics, the non-stick coating having good non-stick properties, improved durability, and improved hardness.

Embodiments of the inventive concept also provide a method for forming a non-stick coating layer using a non-stick material having amorphous characteristics, the non-stick coating layer formed via the method being capable of maintaining amorphous characteristics and having good non-stick properties, improved durability, and improved hardness.

According to an embodiment of the inventive concept, there is provided an amorphous non-stick material for cookware. The amorphous non-stick material comprises, based on the total weight of the amorphous non-stick material: titanium dioxide is more than or equal to 40wt% and less than or equal to 65wt%; iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 55wt%; calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less; phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; and 0.ltoreq.carbon and 5wt% or less silicon, wherein titanium dioxide exists as a titanium phase in the amorphous non-stick material, iron oxide and ferrous oxide coexist as an iron phase in the amorphous non-stick material, and titanium dioxide as a titanium phase has an anatase structure.

In an embodiment, the amorphous non-stick material comprises, based on the total weight of the amorphous non-stick material: titanium dioxide is more than or equal to 50wt% and less than or equal to 65wt%; iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 46wt%; calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less; phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; carbon and silicon are 0-5 wt%.

In an embodiment, the iron phase present in the amorphous non-stick material is black in hue.

In an embodiment, the amorphous non-stick material has pores, and the amorphous non-stick material has a porosity of 0.5% to 2%.

In an embodiment, the amorphous non-stick material is in the form of powder having an average particle diameter of 30 μm to 100 μm.

In an embodiment, calcium oxide is present as a calcium phase in the amorphous non-stick material and magnesium oxide is present as a magnesium phase in the amorphous non-stick material.

According to an embodiment of the inventive concept, there is provided an amorphous non-stick material for cookware. The amorphous non-stick coating comprises, based on the total weight of the amorphous non-stick coating: titanium dioxide is more than or equal to 40wt% and less than or equal to 65wt%; iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 55wt%; calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less; phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; and 0.ltoreq.carbon and silicon.ltoreq.5wt%, wherein titanium dioxide exists as a titanium phase in the amorphous non-stick coating, iron oxide and ferrous oxide coexist as an iron phase in the amorphous non-stick coating, and titanium dioxide as a titanium phase has an anatase type structure.

In an embodiment, the iron phase present in the amorphous non-stick coating is black in hue.

In an embodiment, calcium oxide is present as the calcium phase in the amorphous non-stick coating and magnesium oxide is present as the magnesium phase in the amorphous non-stick coating.

In an embodiment, the amorphous non-stick coating comprises, based on the total weight of the amorphous non-stick coating: titanium dioxide is more than or equal to 50wt% and less than or equal to 65wt%; iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 46wt%; calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less; phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; carbon and silicon are 0-5 wt%.

In an embodiment, the amorphous non-stick coating has pores and the amorphous non-stick coating has a porosity of 2% to 7%.

In an embodiment, the amorphous non-stick coating has a surface energy of 30 dynes to 50 dynes.

In an embodiment, the amorphous non-stick coating has a hardness of 200HV to 600HV.

The amorphous non-stick material according to the inventive concept may include an inorganic material, and may have amorphous characteristics.

The amorphous non-stick coating according to the inventive concept may be formed of an amorphous non-stick material which is an inorganic material and has an amorphous characteristic, and may have improved non-stick and hardness.

Drawings

The foregoing and/or other features and aspects of the present inventive concept will become apparent from the following description of the embodiments taken in conjunction with the accompanying drawings.

Fig. 1 is a schematic sectional view showing a non-stick cooker according to an embodiment.

Fig. 2 is a schematic flowchart showing a preparation method of a non-stick material having amorphous characteristics according to an embodiment.

Fig. 3 is a schematic diagram showing a pulverizing process of obtaining a powdery material of an amorphous non-stick material from ilmenite according to an embodiment.

Fig. 4 is a schematic flow chart showing a method of manufacturing a non-stick coating according to an embodiment.

Detailed Description

Example embodiments of the inventive concepts will be described in more detail below. While example embodiments of the inventive concepts are described below, it should be understood that the inventive concepts may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art.

For conventional non-stick cookware, a fluororesin is generally used as a material of the non-stick coating. For example, a fluororesin non-stick coating having a certain thickness is formed by spraying a fluororesin coating on the surface of a base material of a non-stick cooker. Because of the low surface energy nature of the fluororesin itself, the resulting fluororesin non-stick coating typically has a surface energy of 18 to 25 dynes, enabling non-stick to food during cooking.

However, the fluororesin is a high molecular material, which makes the fluororesin non-stick coating formed therefrom have a low hardness and poor high temperature resistance. For example, such a fluororesin non-stick coating is easily scratched by hard objects, causes breakage and even peeling from a base material, and is thus unsuitable for stir-frying of hard foods. As another example, such fluororesin non-stick coatings generally require that the cooking temperature cannot reach or exceed 260 ℃ for a long period of time, but the cooking temperature is difficult to control during actual cooking. When the fluororesin non-stick coating is used under the condition that the use temperature is beyond the limit, problems such as ageing and decomposition of the fluororesin can occur, and the problems not only affect the service life of the coating, but also seriously damage the human health. For the characteristic that the fluororesin non-stick coating is not resistant to high temperature, a solution to reduce the temperature in the cooker by increasing the thickness of a base material (for example, a cooker body) has been proposed, but in such a way, problems such as reduced heat transfer efficiency, uneven heat distribution and the like occur due to the increase of the thickness of the cooker body, so that the food material is difficult to cook, the cooking experience is poor and the like, and on the other hand, the manufacturing cost of the cooker body is increased. Thus, there is a need for non-stick coatings that compromise non-stick properties, high temperature resistance, and durability.

According to embodiments of the inventive concept, a non-stick material having amorphous characteristics, a non-stick coating layer manufactured from the non-stick material, and a method of manufacturing the non-stick coating layer are provided. Hereinafter, a detailed description will be made thereof.

Referring to fig. 1, a non-stick cookware 100 may include a substrate 110 and a non-stick coating 120.

The substrate 110 may be the body of the non-stick cookware 100 and may include an inner surface for carrying food and an outer surface opposite the inner surface. The substrate 110 may be made of any suitable material commonly used in the art. In addition, the base material 110 may have various shapes according to the type of non-stick cookware and/or the use scene. For example, as shown in fig. 1, when the non-stick cookware 100 is a non-stick pan, the substrate 110 may have a common pan body shape. It should be understood that the main body portion of the non-stick cookware is shown in fig. 1 by way of example only and other portions are not shown, and that the non-stick cookware according to the inventive concept may also include common cookware structures/components such as cookware handles (e.g., pot handles).

The non-stick coating 120 may at least partially cover the substrate 110 to achieve non-stick in the covered area. For example, as shown in fig. 1, the non-stick coating 120 may be disposed on the entire inner surface of the substrate 110, but this is merely an example. Depending on the particular type of non-stick cookware and/or the actual non-stick requirements, a non-stick coating may be formed to cover a portion or all of the surface of the substrate 110. For example, a non-stick coating may be disposed on a portion of the inner surface of the substrate 110 and/or may be further disposed on the outer surface of the substrate 110.

The non-stick coating 120 may include or be formed of a non-stick material having an amorphous characteristic according to an embodiment of the inventive concept. Hereinafter, for convenience of description, the "non-stick material having amorphous characteristics" may also be referred to as "amorphous non-stick material" or "amorphous material".

According to an embodiment of the present invention, the amorphous non-stick material may include titanium oxide and iron oxide, and may further include calcium oxide and magnesium oxide. In addition, in the amorphous non-stick material, at least one of phosphorus (P), carbon (C), and silicon (Si) may also be present. Since the amorphous non-stick material according to the inventive concept includes or is formed of an inorganic material, the amorphous non-stick material may also be referred to as an "amorphous inorganic material".

The titanium oxide, iron oxide, calcium oxide, magnesium oxide described herein may be present in the amorphous non-stick material as a phase of the amorphous non-stick material (e.g., may be considered as a different phase of the amorphous non-stick material), and will be co-present in the amorphous non-stick material in amounts to be described below.

The titanium oxide may be the titanium phase of an amorphous non-stick material. For example, doTitanium oxide, which is a titanium phase, may exist in an amorphous non-stick material in an anatase structure. In embodiments, the titanium oxide may be represented as or may be titanium dioxide (e.g., tiO ₂ ). For example, in an amorphous non-stick material, titanium dioxide as a titanium phase may have an anatase structure.

The iron oxide may be an iron phase of an amorphous non-stick material. For example, the iron oxide as the iron phase may be generally in the form of black iron oxide. As used herein, "black iron oxide" means that the iron oxide present in the amorphous non-stick material is black in hue, but this does not require that the iron oxide be necessarily black iron oxide. Such black iron oxide may be enriched in the amorphous non-stick material, for example, by an amorphous non-stick material pulverizing process which will be described later. In embodiments, the iron oxide may be expressed as "iron oxide and ferrous oxide" or "iron oxide+ferrous oxide" (e.g., "Fe ₂ O ₃ +feo "). Iron oxide and ferrous oxide as iron phases may be present together in the amorphous non-stick material and together appear black in hue.

In an embodiment according to the inventive concept, the amorphous non-stick material may further include a calcium phase and a magnesium phase. In an embodiment, the calcium phase included in the amorphous non-stick material may be represented as or may be calcium oxide, and the magnesium phase included in the amorphous non-stick material may be represented as or may be magnesium oxide. That is, the amorphous non-stick material may include calcium oxide as its calcium phase, and the amorphous non-stick material may include magnesium oxide as its magnesium phase. Accordingly, in this specification, for convenience of description, the magnesium phase and the calcium phase included in the amorphous non-stick material may be collectively denoted as "calcium oxide and magnesium oxide" or "calcium oxide+magnesium oxide" (e.g., "cao+mgo").

The amorphous non-stick material may include a titanium phase and an iron phase and a calcium phase and a magnesium phase. That is, the amorphous non-stick material may include four of a titanium phase, an iron phase, a calcium phase, and a magnesium phase. For the amorphous non-stick material according to the inventive concept, the individual phases included therein are "chelated" to each other to integrally constitute a single material.

As described above, the titanium phase included in the amorphous non-stick material may be represented as titanium dioxide, the iron phase included in the amorphous non-stick material may be represented as iron oxide+ferrous oxide, and the calcium phase and the magnesium phase included in the amorphous non-stick material may be collectively represented as calcium oxide+magnesium oxide. As such, in embodiments according to the inventive concept, the amorphous non-stick material may include titanium dioxide, iron oxide + ferrous oxide, and calcium oxide + magnesium oxide.

In an embodiment, the amorphous non-stick material may include 40wt% or less of titanium dioxide or less of 65wt%, 20wt% or less of iron oxide and ferrous oxide (i.e., iron oxide+ferrous oxide) or less of 55wt%, 3wt% or less of calcium oxide and magnesium oxide (i.e., calcium oxide+magnesium oxide) or less of 10wt%, 0 or less of phosphorus (P) or less of 0.1wt%, and 0 or less of carbon (C) and silicon (Si) (i.e., carbon (C) +silicon (Si)) or less of 5wt% based on the total weight of the amorphous non-stick material. When the amorphous non-stick material has the above-described content ranges of titanium dioxide, iron oxide, and ferrous oxide, the non-stick coating layer having amorphous characteristics formed of the amorphous non-stick material may have non-stick properties. This is because, in the amorphous non-stick material and the non-stick coating layer formed therefrom, three substances of titanium oxide, iron oxide and ferrous oxide as main components are reacted to obtain a plurality of different polyhedral structures under different respective valence states and different conditions, and the different polyhedral structures are "chelated" with each other, and a disordered structure (for example, a short-range disordered structure in a three-dimensional space) similar to that in a conventional amorphous material can occur, so that each atom contained assumes a state of non-uniform orientation, and the surface energy is offset with each other and is reduced as a whole. The non-stick coating formed of an amorphous non-stick material exhibits non-stick properties due to the decrease in surface energy.

In this specification, the term "amorphous nature" is intended to mean a disordered structural nature of a material due to the atoms it contains differing in orientation, and is not intended to limit the material in terms of crystalline/amorphous structure. Such an atomic-level disordered structure allows the amorphous non-stick material according to the inventive concept to have surface energy properties similar to those exhibited by the spatially three-dimensional short-range disordered amorphous structure of conventional amorphous materials. Thus, in the inventive concept, the magnitude of the surface energy may be used to reflect the strength of the amorphous characteristic of the amorphous non-stick material. For example, the stronger the amorphous character of the amorphous non-stick material, the lower the surface energy of the amorphous non-stick material and the amorphous non-stick (coating) formed thereby, and vice versa.

In embodiments, the titanium dioxide may be present in an amount of 40 to 65wt% based on the total weight of the amorphous non-stick material. When having titanium dioxide in this content range as the titanium phase, the amorphous non-stick material and the non-stick coating formed therefrom may exhibit desired amorphous characteristics, and may be appropriate in terms of manufacturing cost. When the content of titanium dioxide is more than 65wt%, the cost of the amorphous non-stick material is high. When the content of titanium dioxide is less than 40wt%, the non-tacky coating formed of an amorphous non-tacky material may not be satisfactory in non-tackiness (for example, the surface energy of the formed coating may not be sufficiently low). Alternatively, the titanium dioxide may be present in an amount of 42 to 63wt% based on the total weight of the amorphous non-stick material. Alternatively, the titanium dioxide may be present in an amount of 50 to 65wt% based on the total weight of the amorphous non-stick material. Alternatively, the titanium dioxide may be present in an amount of 50 to 63wt% based on the total weight of the amorphous non-stick material.

As described above, titanium dioxide, which is a titanium oxide, may exist in an amorphous non-stick material in an anatase structure, and thus constitute a titanium phase of the amorphous non-stick material. The titanium dioxide existing in the anatase structure has more space in the structure, so that the polyhedron structure formed in the reaction process can have more 'change' space, the amorphous non-stick material has more obvious disorder shape, and the amorphous characteristic of the amorphous non-stick material is more obvious. That is, the higher the content of anatase titania in the amorphous non-stick material, the stronger the amorphous property (i.e., the lower the surface energy) of the amorphous non-stick material, and the lower the surface energy of the formed non-stick coating, the better the non-stick, without taking other constraints into consideration.

In embodiments, the iron oxide + ferrous oxide content may be 20 to 55wt% based on the total weight of the amorphous non-stick material. When having iron oxide+ferrous oxide as the iron phase within the content range, the amorphous non-stick material and the non-stick coating formed therefrom may exhibit desired amorphous characteristics, and may have desired hardness. When the content of iron oxide+ferrous oxide is less than 20wt%, the non-stick coating formed of the amorphous non-stick material may not satisfy the expectations in terms of hardness. When the content of iron oxide+ferrous oxide is more than 55wt%, the non-stick coating formed of the amorphous non-stick material may not satisfy the expectations in non-stick properties due to the reduction of the titanium phase. Alternatively, the content of iron oxide + ferrous oxide may be 27 to 48wt% based on the total weight of the amorphous non-stick material. Alternatively, the content of iron oxide + ferrous oxide may be 20 to 40wt% based on the total weight of the amorphous non-stick material. Alternatively, the content of iron oxide + ferrous oxide may be 27 to 40wt% based on the total weight of the amorphous non-stick material. Alternatively, the content of iron oxide + ferrous oxide may be 20 to 46wt% based on the total weight of the amorphous non-stick material.

As described above, iron oxide+ferrous oxide as an iron oxide can also be chelated in an amorphous non-stick material together with titanium dioxide. Further, iron oxides (iron oxide and ferrous oxide) present in the amorphous non-stick material exhibit a black hue as a whole. In contrast, iron oxide+ferrous oxide present in the amorphous non-stick material may not exhibit (or have) a red hue. Iron oxides of black hue exhibit suitable oleophilic properties. In this case, it is possible to facilitate the combination of the non-stick coating formed via the amorphous non-stick material with external oil substances (e.g., edible oil used in cooking, grease leached from the food itself, etc.), thereby further reducing the surface energy of the non-stick coating and improving the non-stick property of the non-stick coating.

Although the description above is made with respect to the titanium phase (e.g., titanium oxide) and the iron phase (e.g., iron oxide) included in the amorphous non-stick material, respectively, particularly with respect to the respective phase contents, it should be understood that the titanium phase (e.g., titanium oxide) and the iron phase (e.g., iron oxide) in the amorphous non-stick material are distinguished for convenience in describing the structure and/or composition of the amorphous material, and thus, such titanium phase and iron phase should be considered as functionally and/or functionally complementary organic integers in achieving the functions and/or effects of the amorphous non-stick material and its non-stick coating as described herein.

For example, when the amorphous non-stick material includes 40 to 65wt% of titanium dioxide and 20 to 55wt% of iron oxide+ferrous oxide based on the total weight thereof, and in the amorphous non-stick material, the titanium dioxide has an anatase structure, the iron oxide+ferrous oxide has a black hue in common, the amorphous non-stick coating formed by the amorphous non-stick material may exhibit desired amorphous characteristics, and may have desired hardness and desired surface energy.

For example, the aforementioned amorphous non-stick coating may have a surface energy of 30 to 50 dynes, which is already quite close to the surface energy (18 to 25 dynes) of the fluororesin non-stick coating, thus being able to meet the non-stick requirement of the non-stick coating. The surface energy of the aforementioned amorphous non-stick coating may be further reduced, i.e. its non-stick properties may be further increased, when it is contacted with e.g. edible oil during cooking. For example, the surface energy of the amorphous non-stick coating may be further reduced to 15-25 dynes due to contact with, for example, edible oil during cooking. That is, the amorphous non-stick coating according to the inventive concept can exhibit non-stick properties comparable to those of the fluororesin coating during actual use.

For example, the hardness of the amorphous non-stick coating may be not lower than 200HV, so that the surface hardness requirement of the non-stick coating can be satisfied, thereby ensuring the lifetime of the non-stick coating. For example, the hardness of the aforementioned amorphous non-stick coating may be 200-600HV.

In an embodiment according to the inventive concept, the amorphous non-stick material may contain a certain amount of impurities. Based on the preparation process of the amorphous non-stick material, a certain amount of impurities can remain in the amorphous non-stick material without being thoroughly removed. Such retention may be in consideration of the limitation of the effectiveness of the impurity removal process, the influence of the impurity residual amount on the non-stick coating performance, the influence of the impurity removal process on the manufacturing cost of the non-stick material, and the like. For example, such retention may involve calcium oxide, magnesium oxide, phosphorus, carbon, and/or silicon as described above.

In embodiments, the content of calcium oxide + magnesium oxide may be 3 to 10wt% based on the total weight of the amorphous non-stick material. In other words, when the calcium phase in the amorphous non-stick material is expressed as calcium oxide and the magnesium phase in the amorphous non-stick material is expressed as magnesium oxide, the content of calcium oxide may be 0 to 10wt%, the content of magnesium oxide may be 0 to 10wt%, and the sum of the contents of calcium oxide and magnesium oxide is 3 to 10wt% in the amorphous non-stick material. Within the foregoing range, the specific content of calcium oxide+magnesium oxide does not affect the surface energy and hardness of the finally formed non-stick coating layer, and thus, redundant description is omitted herein.

In an embodiment, the amorphous non-stick material may include 0 to 0.1wt% of phosphorus (P), 0 to 5wt% of carbon (C), and 0 to 5wt% of silicon (Si), based on the total weight of the amorphous non-stick material, wherein the sum of the contents of carbon (C) and silicon (Si) does not exceed 5wt%. Within the foregoing ranges, the respective specific contents of phosphorus (P), carbon (C) and/or silicon (Si) do not affect the surface energy and hardness of the finally formed non-stick coating layer, and thus redundant descriptions are omitted herein. Further, although the relevant impurities present in the amorphous non-stick material are described herein in elemental form of phosphorus (P), carbon (C), and silicon (Si), it is understood that phosphorus (P), carbon (C), and silicon (Si) as impurities may all be present in the amorphous non-stick material in the form of compounds (e.g., oxides).

That is, the amorphous non-stick material may include calcium oxide, magnesium oxide, phosphorus (P), carbon (C), and/or silicon (Si) as impurities. When the amorphous non-stick material contains the impurity in the above-described content range, the non-crystalline characteristics of the amorphous non-stick material are not affected, and the non-tackiness and hardness of the non-stick coating formed of the amorphous non-stick material are not affected. It should be noted that the impurities described herein are defined based on whether they affect the above-described properties and functions of the amorphous non-stick material and its non-stick coating, and thus need not be trace or even trace. In embodiments, the amorphous non-stick material may also include other impurities, such as Al, mn, cr, nb, ta, V and/or S, etc., which may be present in small, trace or trace amounts, for example. Since these impurities do not affect amorphous characteristics exhibited by mutual "chelation" among the three of titanium oxide, iron oxide, and ferrous oxide as main components, redundant description thereof is omitted herein.

Fig. 2 is a schematic flowchart showing a preparation method of a non-stick material having amorphous characteristics according to an embodiment. Fig. 3 is a schematic diagram showing a pulverizing process of obtaining a powdery material of an amorphous non-stick material from ilmenite according to an embodiment.

Referring to fig. 2, in step S100, ilmenite is prepared. In an embodiment, the ilmenite used herein may be commercially available natural ilmenite. In an embodiment, the ilmenite used herein may be anatase ilmenite. In an embodiment, the ilmenite used herein is not rutile ilmenite.

In step S110, ilmenite is pulverized. After pulverizing, a powder material of a non-stick material having amorphous characteristics can be obtained.

Next, a process of pulverizing ilmenite will be described with reference to fig. 3.

Referring to fig. 3, an amorphous non-stick powder material for manufacturing an amorphous non-stick coating layer may be prepared from ilmenite through the following process.

First, ilmenite is subjected to multistage crushing (e.g., two-stage crushing including primary crushing and secondary crushing), and then subjected to grinding classification. After the aforementioned multi-stage crushing and grinding classification, ilmenite as coarse ore can be refined, thereby obtaining coarse ore and fine ore.

Thereafter, coarse grains obtained in the grinding classification are subjected to a reselection to further classify fine ore and tailings, and then the fine ore is retained and the tailings are removed.

Thereafter, the fine ore obtained through the ore grinding classification and the fine ore obtained through the reselection are subjected to magnetic separation, the enriched ilmenite is retained, and the gangue minerals are removed.

Thereafter, the enriched titanium ore obtained through magnetic separation is subjected to a reselection to select the enriched titanium ore to reduce the content of impurities such as calcium oxide, magnesium oxide, P, etc., and then tailings are removed.

Thereafter, the enriched titanium ore obtained via the re-selection is subjected to titanium roughing to obtain a titanium concentrate.

Thereafter, the ore remaining after the roughing of titanium is subjected to titanium scavenging (i.e., titanium flotation) to adjust the contents of titanium dioxide, iron oxide and ferrous oxide.

Thereafter, the ore remaining after the titanium scavenger is subjected to titanium beneficiation to further adjust the titanium dioxide, iron oxide and ferrous oxide content.

Thus, a powder of the amorphous non-stick material can be obtained.

In an embodiment, the titanium roughing and the titanium scavenging may be repeated to further adjust the content of each substance (phase) contained in the amorphous non-stick powder material. For example, by repeating the titanium roughing and the titanium scavenging, it is possible to appropriately increase the content of titanium dioxide, appropriately decrease the contents of iron oxide and ferrous oxide, and further decrease the contents of calcium oxide, magnesium oxide, P, C, si, and the like. In this way, an amorphous non-stick powder material having a substance (phase) content within the above-described desired range can be obtained according to actual needs.

The amorphous non-stick material prepared through the above process may include 40 to 65wt% of titanium dioxide, 20 to 55wt% of iron oxide + ferrous oxide, and 3 to 10wt% of calcium oxide + magnesium oxide, based on the total weight thereof. In an embodiment, the foregoing amorphous non-stick material may further include 0 to 0.1wt% of P, 0 to 5wt% of C, and 0 to 5wt% of Si (wherein the sum of the contents of C and Si does not exceed 5 wt%). Within such a content range, on the one hand, it is possible to impart desired amorphous characteristics to the amorphous non-stick material and impart desired surface energy and hardness to the non-stick coating formed of the amorphous non-stick material; on the other hand, the process time and the process cost of the powder process can be effectively balanced. In this way, the usability and generalizability of the above-mentioned amorphous non-stick material in the non-stick coating field, especially in the cooker non-stick coating field, can be remarkably promoted.

The powder particles of the amorphous non-stick material prepared through the above process may have a certain porosity. For example, the amorphous non-stick powder particles may have a porosity of 0.5 to 2%. This may be because three substances of titanium dioxide, iron oxide, and ferrous oxide as main components provide various polyhedral structures in the material structure, and the various polyhedral structures form a defect or void in space when "chelated" with each other, such defect or void causing pores to exist in the amorphous non-stick material (or powder particles thereof). Here, the porosity of the amorphous non-stick powder particles can be reflected by the adsorption amount of the grease thereto, and the greater the adsorption amount of the grease under the same external conditions (time and temperature), the greater the porosity of the amorphous non-stick powder particles.

It should be understood that the crushing, grinding and classifying, gravity separation, magnetic separation, roughing and scavenging, etc. involved in the above-mentioned pulverizing process may be performed by various methods commonly used in the related art, so long as the methods can achieve enrichment of titanium phase and iron phase in the finally produced amorphous non-stick material.

Fig. 4 shows a schematic flow chart of a method of manufacturing a non-stick coating according to an embodiment. The non-stick material having amorphous characteristics according to the inventive concept may be formed into a non-stick coating layer via a spray coating method.

Referring to fig. 4, in step S200, an amorphous non-stick material may be prepared. The amorphous non-stick material used herein may be a powder of the amorphous non-stick material prepared through the pulverizing process of fig. 3. The powder of the amorphous non-stick material may have an average particle diameter of 30 to 100 μm and may have a porosity of 0.5 to 2%. The aforementioned powder material may be directly derived from an amorphous non-stick powder material, for example, produced via a pulverizing process described with reference to fig. 3. In addition, the aforementioned powder may be subjected to a grinding or the like process to further obtain a desired average particle diameter, but the embodiment is not particularly limited thereto.

In step S210, an amorphous non-stick material may be sprayed on the substrate surface of the non-stick cookware to form a non-stick coating. A cooker substrate may be prepared. As described with reference to fig. 1, the cookware substrate may be any type of substrate commonly used in the art, such as, but not limited to, iron-based substrates, aluminum-based substrates, and the like. Thereafter, an amorphous non-stick material (e.g., a powder of amorphous non-stick material prepared from the pulverizing process described with reference to fig. 3) may be sprayed to the surface of the cooker substrate using a thermal spraying process to form a non-stick coating layer on the surface of the substrate.

In an embodiment, the spraying of the amorphous non-stick material powder may be performed using thermal spraying. The process parameters of thermal spraying used herein may be: the current is 400-550 amperes (A); the voltage is 40-50 volts (V); the main air flow is 800-2000 liters/hour (L/h); the hydrogen flow is 40-80L/h; the gas flow rate of the powder feeding is 500-800L/h; the powder feeding amount is 40-100 g/min; the spraying distance (the distance between the gun nozzle and the workpiece) is 20-40 centimeters (cm); the spraying angle is 30-80 Degrees (DEG); workpiece temperature: normal temperature. Here, the main gas may be argon. Here, the work refers to a substrate on the surface of which a non-stick coating layer is to be formed by spraying. Further, the room temperature may be room temperature.

By performing thermal spraying of the amorphous non-stick material powder within the above-described process parameter ranges, a non-stick coating layer having amorphous characteristics can be formed on the surface of the substrate to a proper thickness. For example, the non-stick coating formed may have a thickness of 30 to 150 μm. For example, the porosity of the formed non-stick coating may be 2 to 7%. The non-stick coating has properties similar to those of amorphous non-stick materials and thus can have desired non-stick and non-stick durability as well as desired hardness. In other words, the amorphous non-stick coating according to the inventive concept may retain various characteristics of the above-described amorphous non-stick material therein, and thus exhibit desired non-stick properties and desired hardness.

In addition, the amorphous non-stick coating having the porosity in the foregoing range may have a pore oil storage ability, and a low surface energy equivalent to or even superior to that of a fluororesin may be stably obtained by oil storage, thereby stably achieving a non-stick effect.

Here, the porosity of the amorphous non-stick coating can also be reflected by its adsorption amount of grease (such as peanut oil for example), and the greater the adsorption amount of grease, the greater the porosity of the amorphous non-stick coating, under the same external conditions (time and temperature).

The amorphous non-stick material and the non-stick coating layer formed of the amorphous non-stick material according to the present invention will be described below with reference to specific examples and comparative examples.

Examples

Example 1

A powder material for manufacturing a coating layer is prepared, and then the powder material is sprayed on a surface of a base material of a non-stick cooker to form a non-stick coating layer.

The powder used in this example was a powder of an amorphous non-stick material produced by the pulverizing process described with reference to fig. 3.

In this embodiment, the amorphous non-stick material includes 50wt% titanium dioxide, 40wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide, and other impurities (e.g., P, C and Si), based on the total weight of the amorphous non-stick material.

In this example, the average particle diameter of the powder of the amorphous non-stick material was 65. Mu.m.

In the present embodiment, the spraying process of the powder material is performed using thermal spraying. The specific process parameters of thermal spraying are as follows: a current 475A; a voltage of 45V; the main gas (argon) flow is 1400L/h; the hydrogen flow is 60L/h; the flow rate of the powder feeding air is 650L/h; the powder feeding amount is 70g/min; the spraying distance (the distance between the gun nozzle and the workpiece) is 20-40 centimeters (cm); the spraying angle is 30-80 Degrees (DEG); workpiece temperature: room temperature.

In this example, the thickness of the finally formed amorphous material non-stick coating layer was 90 μm.

Example 2

This example differs from example 1 only in that the amorphous non-stick material of this example comprises, based on its total weight, 63wt% titanium dioxide, 27wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities.

Example 3

This example differs from example 1 only in that the amorphous non-stick material of this example comprises 42wt% titanium dioxide, 48wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities, based on its total weight.

Example 4

This example differs from example 1 only in that the amorphous non-stick material of this example comprises 65wt% titanium dioxide, 20wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities, based on the total weight thereof.

Example 5

This example differs from example 1 only in that the amorphous non-stick material of this example comprises 40wt% titanium dioxide, 45wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities, based on the total weight thereof.

Example 6

This example differs from example 1 only in that the amorphous non-stick material of this example comprises 60wt% titanium dioxide, 32wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities, based on the total weight thereof.

Example 7

This example differs from example 1 only in that the amorphous non-stick material of this example comprises 40wt% titanium dioxide, 55wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities, based on the total weight thereof.

Example 8

This example differs from example 1 only in that the amorphous non-stick material of this example comprises 55wt% titanium dioxide, 37wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities, based on the total weight thereof.

Example 9

This example differs from example 1 only in that the amorphous non-stick material of this example comprises 53wt% titanium dioxide, 35wt% iron oxide + ferrous oxide, and the balance calcium oxide, magnesium oxide and other impurities, based on the total weight thereof.

Comparative example 1

Comparative example 1 differs from example 1 only in that the amorphous non-stick material of this example includes 38wt% titanium dioxide, 52wt% iron oxide+ferrous oxide, and the balance calcium oxide, magnesium oxide, and other impurities, based on the total weight thereof.

Comparative example 2

Comparative example 2 differs from example 1 only in that the amorphous non-stick material of comparative example 1 includes 67wt% titanium dioxide, 17wt% iron oxide+ferrous oxide, and the balance calcium oxide, magnesium oxide, and other impurities, based on the total weight thereof.

Test method, evaluation standard and test result

1. Test method and evaluation criterion

1. Surface energy test and evaluation criteria

The contact angles of water and ethylene glycol on the surface of the sample were measured separately by an angulation method using a SINDIN SDC-200SH contact angle measuring instrument at a temperature of 20℃and the surface energy of the sample was calculated using an OWRK method. Here, the samples refer to the non-stick coating of examples 1 to 9 and comparative examples 1 and 2.

For the surface energy test, when the measured surface energy value of the sample is more than 50 dynes, the sample is not good in non-tackiness and long-lasting non-tackiness, and cannot meet the requirement of 5000 times of long-lasting non-tackiness in the national standard. In contrast, a sample can be considered to meet the requirements of non-tackiness and long-lasting non-tackiness when its measured surface energy value is no greater than 50 dynes.

2. Hardness test and evaluation criteria

The samples were tested for vickers hardness using the vickers hardness test, wherein the hardness number units are HV. Here, the samples refer to the non-stick coating of examples 1 to 9 and comparative examples 1 and 2.

For the hardness test, the greater the measured hardness value, the harder the sample. When the sample is a non-stick coating, the hardness is higher, which means that the non-stick coating is harder, the non-stick coating has stronger abrasion resistance to a shovel and food materials, and is less prone to being abraded, so that the service life of the coating is longer. Generally, the hardness of the non-stick coating must not be lower than 200HV.

2. Test results

The surface energy test results and hardness test results of the non-stick coating layers in examples 1 to 9 and comparative examples 1 and 2 described above are shown in table 1 below.

TABLE 1

As can be seen from the above test results, the amorphous non-stick coating formed of the amorphous non-stick material according to the inventive concept can have a surface energy of not more than 50 dynes and can have a hardness of more than 200HV. Accordingly, the amorphous non-stick coating according to the inventive concept has desired non-stick and non-stick durability, and has desired hardness. Furthermore, the amorphous non-stick coating of comparative example 1 exhibited a surface energy value of higher than 50 and poor non-stick properties due to the inclusion of a lower amount of titanium dioxide. The amorphous non-stick coating of comparative example 2 exhibited hardness values below 200HV and shorter service lives due to the lower amounts of iron oxide and ferrous oxide contained.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims and their equivalents. The embodiments should be considered in descriptive sense only and not for purposes of limitation. Therefore, the scope of the invention is defined not by the specific embodiments of the invention but by the claims, and all differences within the scope will be construed as being included in the present invention.

Claims

1. An amorphous non-stick material for cookware, the amorphous non-stick material comprising, based on the total weight of the amorphous non-stick material:

titanium dioxide is more than or equal to 40wt% and less than or equal to 65wt%;

iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 55wt%;

calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less;

phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; and

carbon and silicon are not less than 0 and not more than 5wt%,

wherein titanium dioxide is present as a titanium phase in the amorphous non-stick material and iron oxide and ferrous oxide are present together as an iron phase in the amorphous non-stick material,

wherein the titanium dioxide as the titanium phase has an anatase structure, and

wherein an iron phase present in the amorphous non-stick material is black in hue.

2. The amorphous non-stick material of claim 1, wherein the amorphous non-stick material comprises, based on the total weight of the amorphous non-stick material: titanium dioxide is more than or equal to 50wt% and less than or equal to 65wt%; iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 46wt%; calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less; phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; carbon and silicon are 0-5 wt%.

3. The amorphous non-stick material of claim 1, wherein the amorphous non-stick material has pores and the amorphous non-stick material has a porosity of 0.5% to 2%.

4. The amorphous non-stick material according to claim 1, wherein the amorphous non-stick material is in the form of powder having an average particle diameter of 30 μm to 100 μm.

5. The amorphous non-stick material of claim 1, wherein calcium oxide is present in the amorphous non-stick material as a calcium phase and magnesium oxide is present in the amorphous non-stick material as a magnesium phase.

6. An amorphous non-stick coating for cookware, the amorphous non-stick coating comprising, based on the total weight of the amorphous non-stick coating:

phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; and

carbon and silicon are not less than 0 and not more than 5wt%,

wherein titanium dioxide is present as a titanium phase in the amorphous non-stick coating and iron oxide and ferrous oxide are present together as an iron phase in the amorphous non-stick coating,

wherein the iron phase present in the amorphous non-stick coating is black in hue.

7. The amorphous non-stick coating of claim 6, wherein calcium oxide is present in the amorphous non-stick coating as a calcium phase and magnesium oxide is present in the amorphous non-stick coating as a magnesium phase.

8. The amorphous non-stick coating of claim 6, wherein the amorphous non-stick coating comprises, based on the total weight of the amorphous non-stick coating: titanium dioxide is more than or equal to 50wt% and less than or equal to 65wt%; iron oxide and ferrous oxide are more than or equal to 20wt% and less than or equal to 46wt%; calcium oxide and magnesium oxide accounting for 3wt% or more and 10wt% or less; phosphorus is more than or equal to 0 and less than or equal to 0.1wt%; carbon and silicon are 0-5 wt%.

9. The amorphous non-stick coating of claim 6, wherein the amorphous non-stick coating has pores and the amorphous non-stick coating has a porosity of 2% to 7%.

10. The amorphous non-stick coating of claim 6, wherein the amorphous non-stick coating has a surface energy of 30 to 50 dynes.

11. The amorphous non-stick coating of claim 6, wherein the amorphous non-stick coating has a hardness of 200HV to 600HV.