阅读说明：本技术 包含热致变色复合涂层的炊具的制造方法及通过该方法制造的炊具 (Method for manufacturing cookware comprising thermochromic composite coating and cookware manufactured by the method ) 是由 孙载奉 于 2020-05-08 设计创作，主要内容包括：本发明涉及包含热致变色复合涂层的炊具的制造方法及通过该方法制造的炊具。在一具体例中,所述包含热致变色复合涂层的炊具的制造方法包括：底漆层形成步骤,在金属基材表面形成包含氟树脂的底漆层；调色层形成步骤,在所述底漆层表面的至少一部分涂敷包含基质树脂及调色颜料的调色涂敷剂来形成调色层；热致变色层形成步骤,在所述底漆层表面的至少一部分涂敷包含热致变色化合物及变色颜料的热致变色涂敷剂来形成热致变色层；以及顶涂层形成步骤,在形成所述热致变色层的底漆层表面涂敷顶涂敷剂并进行热处理来形成顶涂层,所述顶涂敷剂包含100重量份的氟基树脂、10重量份～50重量份的烷氧基硅烷化合物、5重量份～50重量份的第一颜料、0.5重量份～15重量份的二硫化钼以及1重量份～15重量份的磷酸酯类化合物。(The present invention relates to a method of manufacturing cookware comprising a thermochromic composite coating and cookware manufactured by the method. In one embodiment, the method of making cookware comprising a thermochromic composite coating includes: a primer layer forming step of forming a primer layer containing a fluororesin on a surface of a metal substrate; a toning layer forming step of forming a toning layer by applying a toning coating agent containing a base resin and a toning pigment to at least a part of the surface of the primer layer; a thermochromic layer forming step of forming a thermochromic layer by applying a thermochromic coating agent containing a thermochromic compound and a color-changing pigment to at least a part of the surface of the primer layer; and a top coat layer forming step of forming a top coat layer by applying a top coat agent comprising 100 parts by weight of a fluorine-based resin, 10 to 50 parts by weight of an alkoxysilane compound, 5 to 50 parts by weight of a first pigment, 0.5 to 15 parts by weight of molybdenum disulfide, and 1 to 15 parts by weight of a phosphate ester compound on the surface of the primer layer on which the thermochromic layer is formed and performing a heat treatment.)

1. A method of manufacturing a cookware comprising a thermochromic composite coating, wherein,

the method comprises the following steps:

a primer layer forming step of forming a primer layer containing a fluororesin on a surface of a metal substrate;

a toning layer forming step of forming a toning layer by applying a toning coating agent containing a base resin and a toning pigment to at least a part of the surface of the primer layer;

a thermochromic layer forming step of forming a thermochromic layer by applying a thermochromic coating agent containing a thermochromic compound and a color-changing pigment to at least a part of the surface of the primer layer; and

a top coat layer forming step of applying a top coat agent on the surface of the primer layer on which the thermochromic layer is formed and performing heat treatment to form a top coat layer,

the top coating agent comprises 100 weight portions of fluorine-based resin, 10 to 50 weight portions of alkoxy silane compound, 5 to 50 weight portions of first pigment, 0.5 to 15 weight portions of molybdenum disulfide and 1 to 15 weight portions of phosphate compound,

the hueing pigment comprises a titanium oxide and,

the color-changing pigment comprises iron oxide red.

2. The method of manufacturing cookware comprising a thermochromic composite coating according to claim 1, wherein said heat treatment is performed at a temperature of 380 ℃ to 450 ℃.

3. The method of manufacturing cookware comprising a thermochromic composite coating according to claim 1,

the top coating agent further contains 0.5 to 5 parts by weight of germanium oxide with respect to 100 parts by weight of the fluorine-based resin,

the top coating agent comprises the germanium oxide and the phosphate compound in a weight ratio of 1: 1-1: 5.

4. The method of manufacturing a cooker including a thermochromic composite coating according to claim 1, wherein the color modulation layer and the thermochromic layer are formed by pad printing, respectively.

5. The method of manufacturing cookware comprising a thermochromic composite coating according to claim 1,

the primer layer is formed of a primer agent,

the primer agent comprises 100 parts by weight of fluorine-based resin, 1-40 parts by weight of second pigment, 1-15 parts by weight of phosphate compound and 0.5-5 parts by weight of germanium oxide.

6. The method for manufacturing a cooker including a thermochromic composite coating according to claim 1, wherein the fluororesin includes one or more of polytetrafluoroethylene, a tetrafluoroethylene-hexafluoropropylene copolymer, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and polyvinylidene fluoride.

7. The method of manufacturing cookware comprising a thermochromic composite coating according to claim 1,

the toning coating agent comprises 100 weight portions of matrix resin and 0.5 to 50 weight portions of toning pigment,

the thermochromic coating agent comprises 100 parts by weight of thermochromic compound and 0.5-30 parts by weight of color-changing pigment,

the thermochromic compound contains more than one of mercuric iodide complex salt and vanadium oxide.

8. The method of making cookware comprising a thermochromic composite coating according to claim 1, wherein said first pigment comprises one or more of carbon black, perylene red, manganese iron black, copper chromium black, bismuth vanadate, iron hydroxide yellow, chromium oxide green, and cobalt aluminum blue.

9. A cooking utensil, wherein,

comprises the following steps:

a metal substrate;

a primer layer formed on one or more surfaces of the metal substrate, and containing a fluororesin;

a color control layer formed on at least a portion of a surface of the primer layer;

a thermochromic layer formed on at least a portion of a surface of the primer layer; and

a top coating layer formed on the surfaces of the primer layer and the thermochromic layer,

the top coat layer is formed by a top coat agent, the top coat agent comprises 100 weight parts of fluorine-based resin, 10 to 50 weight parts of alkoxy silane compound, 5 to 50 weight parts of first pigment, 0.5 to 15 weight parts of molybdenum disulfide and 1 to 15 weight parts of phosphate ester compound,

the color control layer is formed by a toning coating agent, the toning coating agent comprises a matrix resin and a toning pigment,

the thermochromic layer is formed by a thermochromic coating agent which comprises a thermochromic compound and a color-changing pigment,

the hueing pigment comprises a titanium oxide and,

the color-changing pigment comprises iron oxide red.

Technical Field

The present invention relates to a method of manufacturing cookware comprising a thermochromic composite coating and cookware manufactured by the method.

Background

Frying pans (Frypan), frying pans, stockpots, and the like, which are heating cookers having a heat-resistant and corrosion-resistant coating formed on the surface thereof in contact with the food to be cooked, are made of metal materials.

On the other hand, when cooking is performed using the above-described cooker for heating, there is a problem in that it is difficult to clearly judge to what extent the cooker is heated by the fire. In order to solve the above problems, a coating agent containing a thermochromic pigment is coated on the surface of a cooker and hardened to form a thermochromic coating, thereby producing a cooker which can grasp a heated state by thermochromic change of the coating.

The background art related to the present invention is Korean patent laid-open publication No. 10-1686414 (published on 2016, 12, 14, entitled: ceramic coating capable of indicating a heated state, method for preparing ceramic paint, method for applying the same, and heating device using the same).

Disclosure of Invention

Technical problem

An object of the present invention is to provide a method of manufacturing a cooker including a thermochromic composite coating, which is capable of easily discriminating a heating state of the cooker.

It is still another object of the present invention to provide a method for manufacturing a cooker including a thermochromic composite coating having excellent wear resistance, durability, and interlayer adhesion of the composite coating.

Another object of the present invention is to provide a method for manufacturing a cooker including a thermochromic composite coating, which has excellent thermal conductivity and antifouling property, and is excellent in non-stick (non-stick) property that food materials do not stick to the surface of the composite coating when cooked.

It is still another object of the present invention to provide a cooker manufactured by the method of manufacturing the cooker.

Means for solving the problems

One aspect of the present invention relates to a method of making cookware comprising a thermochromic composite coating. In one embodiment, the method of making cookware comprising a thermochromic composite coating includes: a primer layer forming step of forming a primer layer containing a fluororesin on a surface of a metal substrate; a toning layer forming step of forming a toning layer by applying a toning coating agent containing a base resin and a toning pigment to at least a part of the surface of the primer layer; a thermochromic layer forming step of forming a thermochromic layer by applying a thermochromic coating agent containing a thermochromic compound and a color-changing pigment to at least a part of the surface of the primer layer; and a top coat layer forming step of forming a top coat layer by applying a top coat agent on the surface of the primer layer on which the thermochromic layer is formed and performing a heat treatment, wherein the top coat agent includes 100 parts by weight of a fluorine-based resin, 10 to 50 parts by weight of an alkoxysilane compound, 5 to 50 parts by weight of a first pigment, 0.5 to 15 parts by weight of molybdenum disulfide, and 1 to 15 parts by weight of a phosphate compound, the toning pigment includes titanium oxide, and the color-changing pigment includes iron oxide red.

In one embodiment, the heat treatment may be performed at a temperature of 380 ℃ to 450 ℃.

In one embodiment, the top coating agent may further include 0.5 to 5 parts by weight of germanium oxide with respect to 100 parts by weight of the fluorine-based resin, and the top coating agent may include the germanium oxide and the phosphate compound in a weight ratio of 1: 1 to 1: 5.

In one embodiment, the color modulation layer and the thermochromic layer may be formed by pad printing, respectively.

In one embodiment, the primer layer may be formed of a primer agent, and the primer agent may include 100 parts by weight of a fluorine-based resin, 1 to 40 parts by weight of a second pigment, 1 to 15 parts by weight of a phosphate compound, and 0.5 to 5 parts by weight of germanium oxide.

In one embodiment, the fluororesin may include one or more of Polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and polyvinylidene fluoride (PVDF).

In one embodiment, the color-adjusting coating agent may include 100 parts by weight of a matrix resin and 0.5 to 50 parts by weight of a color-adjusting pigment, the thermochromic coating agent may include 100 parts by weight of a thermochromic compound and 0.5 to 30 parts by weight of a color-changing pigment, and the thermochromic compound may include one or more of a mercury iodide complex salt and a vanadium oxide.

In one embodiment, the first pigment can include one or more of carbon black, perylene red, manganese iron black, copper chromium black, bismuth vanadate, iron hydroxide yellow, chromium oxide green, and cobalt aluminum blue.

Another aspect of the present invention relates to a cooker manufactured by the manufacturing method of the cooker. In one embodiment, the cookware comprises: a metal substrate; a primer layer formed on one or more surfaces of the metal substrate, and containing a fluororesin; a color control layer formed on at least a portion of a surface of the primer layer; a thermochromic layer formed on at least a portion of a surface of the primer layer; and a top coat layer formed on the surfaces of the primer layer and the thermochromic layer, wherein the top coat layer is formed by a top coating agent, the top coating agent comprises 100 parts by weight of fluorine-based resin, 10-50 parts by weight of alkoxysilane compound, 5-50 parts by weight of first pigment, 0.5-15 parts by weight of molybdenum disulfide and 1-15 parts by weight of phosphate ester compound, the color adjusting layer is formed by a color adjusting coating agent, the color adjusting coating agent comprises matrix resin and color adjusting pigment, the thermochromic layer is formed by a thermochromic coating agent, the thermochromic coating agent comprises a thermochromic compound and a color changing pigment, and the color adjusting pigment comprises titanium oxide. The color-changing pigment comprises iron oxide red.

ADVANTAGEOUS EFFECTS OF INVENTION

When the cooker containing the thermochromic composite coating of the present invention is applied, the thermochromic layer does not appear on the surface at normal temperature, and when heated to a temperature above a predetermined temperature, the thermochromic layer appears and is distinguishable on the surface of the cooker, so that the heating state of the cooker can be easily distinguished, and the thermochromic composite coating has excellent wear resistance, durability, interlayer adhesion of the composite coating, thermal conductivity, and antifouling property, so that it can be conveniently cleaned and managed, and food materials are not stuck to the surface of the composite coating during cooking, and the non-stick property is excellent.

Drawings

FIG. 1 is a flowchart showing a method for manufacturing a cooker according to an embodiment of the present invention;

FIG. 2 diagrammatically illustrates a cookware manufacturing method of the invention;

FIG. 3 is a photograph of a cooker manufactured according to example 1;

fig. 4 is a photograph after heating the cooker manufactured according to example 1.

Detailed Description

When the present invention is explained, a detailed explanation thereof will be omitted in a case where it is judged that a detailed explanation of the related known technology or structure may unnecessarily obscure the gist of the present invention.

The terms described below are defined in consideration of functions of the present invention, and may be defined based on the entire specification describing the present invention because the terms may be different depending on intentions of a user and an operator or conventions.

A method of making cookware comprising a thermochromic composite coating.

One aspect of the present invention relates to a method of making cookware comprising a thermochromic composite coating. Fig. 1 is a flowchart showing a method of manufacturing a cooker according to an embodiment of the present invention, and fig. 2 shows the method of manufacturing a cooker according to the present invention in a schematic manner. Referring to fig. 1 and 2, a method of manufacturing a cooker includes: step S10, forming a primer layer; step S20, forming a color adjusting layer; step S30, forming a thermochromic layer; and step S40, forming a top coating layer and performing heat treatment. More specifically, the method of manufacturing the cooker including the thermochromic composite coating includes: a step S10 of forming a primer layer containing a fluororesin on a surface of a metal base material; a step S20 of applying a toning coating agent containing a base resin and a toning pigment to at least a part of the surface of the primer layer to form a toning layer; step S30 of forming a thermochromic layer by applying a thermochromic coating agent containing a thermochromic compound and a color-changing pigment to at least a part of the surface of the primer layer; and a step S40 of coating a top coating agent on the surface of the primer layer on which the thermochromic layer is formed and performing a heat treatment to form a top coating layer.

In this specification, the term "thermochromic composite coating" is defined to include primer layers, tinting layers, thermochromic layers, and topcoat layers.

Hereinafter, a method for manufacturing a cooker including a thermochromic composite coating according to the present invention will be described in accordance with the steps.

Primer layer Forming step (step S10)

The step is a step of forming a primer layer by applying a primer agent containing a fluororesin to at least a part of a metal substrate and drying the primer agent.

Referring to the portion (a) of fig. 2, a primer layer 20 may be formed on a surface of the metal substrate 10 contacting the cooking material. In one embodiment, the metal substrate 10 may include one or more of aluminum, aluminum alloy, copper, manganese, aluminum-plated steel, iron, and stainless steel.

In one embodiment, the surface of the metal substrate to which the primer agent is applied may be subjected to sand blasting (sand blasting) prior to application of the primer agent. When the sand blast treatment is performed, the surface area of the metal substrate may be increased, thereby making the adhesion of the primer layer excellent.

In one embodiment, the primer layer may be formed of a primer agent, and the primer agent may include 100 parts by weight of a fluorine-based resin, 5 to 50 parts by weight of a second pigment, 1 to 15 parts by weight of a phosphate compound, and 0.5 to 5 parts by weight of germanium oxide.

In one embodiment, the fluororesin may include one or more of polytetrafluoroethylene, a tetrafluoroethylene-hexafluoropropylene copolymer, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and polyvinylidene fluoride. When the fluororesin is used, the primer layer can be made excellent in chemical resistance, wear resistance, durability, and heat resistance. For example, the resin composition may contain one or more of polytetrafluoroethylene and a tetrafluoroethylene-hexafluoropropylene copolymer.

In one embodiment, the second pigment can include one or more of carbon black, perylene red, manganese iron black, copper chromium black, bismuth vanadate, iron hydroxide yellow, chromium oxide green, and cobalt aluminum blue. For example, ferromanganese black and perylene red may be included. In one specific example, the second pigment may be included in an amount of 1 to 40 parts by weight, relative to 100 parts by weight of the fluororesin. When the second pigment is included in the range, the miscibility and dispersibility of the primer agent are not reduced, and the durability and mechanical physical properties of the primer layer may be prevented from being reduced. For example, the second pigment may be included in an amount of 5 to 20 parts by weight.

In one embodiment, the average particle diameter of the second pigment may be 5 μm to 30 μm. In the above range, the dispersibility and the mixability can be excellent.

The phosphate ester compound can be used for the purpose of improving the durability and adhesion to the substrate of the primer layer of the present invention. The phosphate ester compound may be one containing one or more of a hydroxyl group and a carboxyl group.

In one embodiment, the phosphate ester compound is contained in an amount of 1 to 15 parts by weight based on 100 parts by weight of the fluororesin. When the phosphate ester compound is included in the range, the durability and the adhesion of the primer layer may be excellent, and an excessive increase in the viscosity of the primer agent may be prevented. For example, the phosphate ester compound may be contained in an amount of 1 to 8 parts by weight.

The germanium oxide can be used for improving the adhesive force among the metal base material, the primer layer and the top coating layer. In one specific example, the germanium oxide may be included in an amount of 0.5 to 5 parts by weight, relative to 100 parts by weight of the fluororesin. Under such conditions, the primer of the present invention can be made excellent in miscibility and dispersibility and also excellent in interlayer adhesion of the primer layer. For example, the germanium oxide may be included in an amount of 1 to 3 parts by weight.

In one embodiment, the germanium oxide and the phosphate compound may be included in a weight ratio of 1: 1 to 1: 5. When the germanium oxide and the phosphate ester compound are included in the above weight ratio range, the primer mixture and the workability are excellent, and the interlayer adhesion and the durability of the primer layer are excellent. For example, germanium oxide and a phosphate compound may be included in a weight ratio of 1: 2 to 1: 4.

In one embodiment, the primer agent may further comprise a solvent. The solvent may include one or more of water, alcohol having 1 to 10 carbon atoms, toluene, xylene, diisobutyl ketone, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, 1-methoxy-2-propanol, ethanol, ethylene glycol butyl ether, cyclohexane, N-butyl acetate, N-methylpyrrolidone, dimethylformamide, ethyl acetate, acetone, methyl acetate, isobutyl acetate, isopropyl acetate, and dimethyl carbonate. In one embodiment, the alcohol having 1 to 10 carbon atoms may include one or more of methanol, ethanol, propanol, isopropanol, n-butanol, and isobutanol.

The solvent may be contained in an amount of 10 to 500 parts by weight with respect to 100 parts by weight of the fluororesin. When the solvent is contained in the range, the composition of the primer agent can be easily adjusted, and the dispersibility and the workability are excellent.

In one embodiment, the primer agent may further include additives such as a surfactant, a leveling agent, and an antifoaming agent. The additive may be included in an amount of 0.1 to 20 parts by weight, relative to 100 parts by weight of the fluororesin.

The primer agent can be prepared by a usual method.

In one embodiment, the primer agent may be applied and dried at a temperature of 80 ℃ to 160 ℃ to form a primer layer. When dried under the above conditions, the smoothness and durability of the primer layer can be made excellent. The primer agent may be applied by a usual method. For example, the coating may be applied using an air sprayer.

In one embodiment, the primer agent may be applied more than once by changing the color of the second pigments, respectively. For example, a first primer agent including 100 parts by weight of a fluorine-based resin, 5 to 50 parts by weight of a second pigment including perylene red, 1 to 15 parts by weight of a phosphate compound, and 0.5 to 5 parts by weight of germanium oxide may be applied to one side of a metal substrate to form a first primer layer. Then, a second primer agent comprising 100 parts by weight of a fluorine-based resin, 5 to 50 parts by weight of a second pigment comprising ferromanganese black or carbon black, 1 to 15 parts by weight of a phosphate-based compound, and 0.5 to 5 parts by weight of germanium oxide is applied to at least a portion of the surface of the first primer layer and dried at a temperature of 80 to 160 ℃ to form a second primer layer. When dried under the above conditions, the primer layer can be made excellent in smoothness and durability. The primer agent may be applied by conventional methods. For example, the coating may be applied using an air sprayer.

In one embodiment, the primer layer may have a thickness of 5 μm to 30 μm. Under the thickness condition, the durability of the primer layer can be made excellent.

Tone layer Forming step (step S20)

The step is a step of forming a color-adjusting layer containing a matrix resin and a color-adjusting pigment on at least a part of the surface of the primer layer. As shown in part (b) of fig. 2, the step may transfer a toning coating agent to at least a portion of the surface of the primer layer 20 to form a toning layer 30.

In one embodiment, the toning coating agent may include a matrix resin and a toning pigment. When the matrix resin and the toning pigment are contained in the above ranges, the workability and the durability of the toning layer can be made excellent.

For example, the matrix resin may include one or more of polyetheretherketone, polyurethane, polyvinyl sulfide, polyphenylene sulfide, ethylcellulose, polyvinyl alcohol, and polyvinylpyrrolidone, but is not limited thereto.

In one embodiment, the toning pigment includes titanium oxide. The titanium oxide (TiO2) is used to make white color, and the color (pattern) of the thermochromic layer, which is developed when the cooker described later is heated, can be more clearly distinguished.

In one embodiment, the average particle size of the toning pigment can be 5 μm to 30 μm. In the above range, the dispersibility and the thermochromic effect can be excellent.

In one embodiment, the toning coating agent may include 100 parts by weight of the matrix resin and 0.5 to 50 parts by weight of a toning pigment. When the matrix resin and the toning pigment are contained in the above ranges, the dispersibility and mixability of the components of the toning coating agent can be improved, and the adhesion of the coating layer can be improved.

In one embodiment, the toner coating agent may further include a solvent. The solvent may include one or more of water, alcohol having 1 to 10 carbon atoms, toluene, xylene, diisobutyl ketone, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, 1-methoxy-2-propanol, ethanol, ethylene glycol butyl ether, cyclohexane, N-methylpyrrolidone, dimethylformamide, N-butyl acetate, ethyl acetate, acetone, methyl acetate, isobutyl acetate, isopropyl acetate, and dimethyl carbonate. In one embodiment, the alcohol having 1 to 10 carbon atoms may include one or more of methanol, ethanol, propanol, isopropanol, n-butanol, and isobutanol.

In one embodiment, the solvent may be included in an amount of 10 to 300 parts by weight, relative to 100 parts by weight of the matrix resin. When the solvent is contained in the above range, the viscosity of the composition of the toner coating agent can be easily adjusted, and the mixing property, dispersibility, and workability can be excellent.

In one embodiment, the toner coating agent may be pad printed or applied and then dried. The drying may be carried out at 80 to 150 ℃. Under the conditions, the durability of the color control layer can be made excellent.

In one embodiment, the thickness of the color modulation layer may be 1 μm to 30 μm. Under the thickness condition, the durability of the color modulation layer can be made excellent.

Thermochromic layer formation step (step S30)

As shown in part (c) of fig. 2, the step is a step of pad-printing a thermochromic coating agent including a thermochromic compound and a color-changing pigment on at least a portion of the surface of the primer layer 20 to form a thermochromic layer 40.

In one embodiment, the thermochromic coating agent may include 100 parts by weight of the thermochromic compound and 0.5 to 30 parts by weight of the color-changing pigment. When the thermochromic compound and the color-changing pigment are contained in the above ranges, the operability and the effectiveness and reliability of the thermochromic can be made excellent.

In the case of the conventional heating device, although the phenomenon that thermochromism occurs when the heating device is heated to a predetermined temperature or higher is utilized, the thermochromism is difficult to be confirmed, and thus the heating state is difficult to be distinguished. In contrast, the present invention does not cause discoloration of the thermochromic layer at normal temperature, does not develop the thermochromic layer (pattern), but develops the discoloration of the thermochromic layer (pattern) when heated to a prescribed temperature or higher, thereby enabling easy discrimination of the heated state of the cooker. In particular, in one specific example, a red pigment such as perylene red is used as the first pigment or the second pigment of the primer layer or the topcoat layer, and the pigment can be formed so as to be invisible to the naked eye at normal temperature by combining colors with the thermochromic layer.

In one embodiment, the color changing pigment comprises red iron oxide. When the thermochromic layer is formed using the color-changing pigment under the above conditions, the discriminability can be made excellent and also excellent aesthetic quality can be given to a user. In particular, at normal temperature, the color (or pattern) of the thermochromic layer does not appear on the surface of the cookware, and changes color to appear when heated to a predetermined temperature or higher, so that the distinguishability can be made excellent.

In one embodiment, the average particle diameter of the color-changing pigment may be 5 μm to 30 μm. In the above range, the dispersibility and the thermochromic effect can be excellent.

In one embodiment, the color-changing pigment may be included in an amount of 0.5 to 30 parts by weight, relative to 100 parts by weight of the thermochromic compound. When the color-changing pigment is contained in the above range, the dispersibility and workability of the components of the thermochromic coating agent can be made excellent. When the color-changing pigment is contained in the above range, the workability and the effectiveness and reliability of the thermochromic color-changing can be made excellent.

The thermochromic compound may include one or more of a mercury iodide complex salt and a vanadium oxide.

In one embodiment, the mercury iodide complex salt may comprise mercury silver iodide (Ag)₂HgI₄) And copper mercuric iodide (Cu)₂HgI₄) More than one of them.

In one embodiment, the thermochromic coating agent may further include a solvent. The solvent may include one or more of water, alcohol having 1 to 10 carbon atoms, toluene, xylene, diisobutyl ketone, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, 1-methoxy-2-propanol, ethanol, ethylene glycol butyl ether, cyclohexane, N-butyl acetate, N-methylpyrrolidone, dimethylformamide, ethyl acetate, acetone, methyl acetate, isobutyl acetate, isopropyl acetate, and dimethyl carbonate. In one embodiment, the alcohol having 1 to 10 carbon atoms may include one or more of methanol, ethanol, propanol, isopropanol, n-butanol, and isobutanol.

In one embodiment, the solvent may be included in an amount of 10 to 300 parts by weight, relative to 100 parts by weight of the thermochromic compound. When the solvent is contained in the above range, the dispersibility and the workability of the components of the thermochromic coating agent can be made excellent.

In one embodiment, the thermochromic layer may be formed using pad printing.

In one embodiment, the toner coating agent may be pad printed or applied and then dried. In one embodiment, the drying may be performed at 80 ℃ to 150 ℃. Under the conditions, the durability of the thermochromic layer can be made excellent.

In one embodiment, the thermochromic layer may have a thickness of 1 μm to 30 μm. Under the thickness condition, the durability of the thermochromic layer can be made excellent.

Top coat layer formation and Heat treatment step (step S40)

As shown in part (d) of fig. 2, the step is a step of coating a topcoat agent containing a fluororesin on the surface of the primer layer on which the thermochromic layer 40 is formed and heat-treating to form a topcoat layer 50. In one embodiment, as shown in fig. 2 (d), the top coat layer may be formed on the surface of the toning layer 30, the surface of the thermochromic layer 40, and the surface of the primer layer 20. If such heat treatment is not applied, defects such as a decrease in adhesion of the coating layer and a decrease in smoothness of the surface of the coating layer may occur.

The topcoat layer can prevent damage to the color control layer and the thermochromic layer, and can provide excellent non-tackiness to the cooked food material, and excellent wear resistance, thermal conductivity, chemical resistance, smoothness, and durability.

Further, when the top coat layer of the present invention is formed, the thermochromic layer may be made to appear to be distinguishable when heated to a predetermined temperature or higher without appearing on the surface at normal temperature.

In one embodiment, the top coating agent includes 100 parts by weight of a fluorine-based resin, 10 to 50 parts by weight of an alkoxysilane compound, 5 to 50 parts by weight of a first pigment, 0.5 to 15 parts by weight of molybdenum disulfide, and 1 to 15 parts by weight of a phosphate ester compound.

In one embodiment, the fluororesin may include one or more of polytetrafluoroethylene, a tetrafluoroethylene-hexafluoropropylene copolymer, a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and polyvinylidene fluoride. When the fluororesin is used, the top coat layer can be made excellent in smoothness, chemical resistance, durability and heat resistance.

The alkoxysilane compound can improve adhesion and durability between the topcoat layer, the color control layer, the thermochromic layer, and the primer layer.

In one embodiment, the alkoxysilane may include one or more of glycidoxypropyltrimethoxysilane, mercaptopropyltriethoxysilane, methacryloxypropyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, methacryloxypropyltriethoxysilane, and glycidoxypropyltriethoxysilane.

The alkoxysilane compound may be contained in an amount of 10 to 50 parts by weight based on 100 parts by weight of the fluorine-based resin. If the alkoxysilane compound is contained in an amount of less than 10 parts by weight, the durability and adhesion of the top coat layer are reduced, and if the alkoxysilane compound is contained in an amount of more than 50 parts by weight, the mixability and workability of the top coat agent, the smoothness and appearance of the top coat layer may be deteriorated. For example, the alkoxysilane compound may be contained in an amount of 15 to 35 parts by weight.

In one embodiment, the first pigment may include one or more of carbon black, perylene red, ferromanganese black, copper chromium black, bismuth vanadate, iron hydroxide yellow, chromium oxide green, and cobalt aluminum blue. For example, ferromanganese black and perylene red may be included.

In one embodiment, the first pigment is contained in an amount of 5 to 50 parts by weight relative to 100 parts by weight of the fluororesin. When the first pigment is contained in the range, dispersibility can be excellent, and the durability and mechanical properties of the top coat layer can be prevented from being lowered. If the first pigment is contained in an amount of less than 5 parts by weight, the addition effect is very little, and if the first pigment is contained in an amount of more than 50 parts by weight, it is difficult to disperse in the top coating agent, thereby reducing the appearance and durability of the top coating layer. For example, the first pigment may be included in an amount of 10 to 40 parts by weight.

In one embodiment, the first pigment may have an average particle diameter of 5 μm to 30 μm. In the above range, the dispersibility and the mixability can be excellent.

The molybdenum disulfide (MoS2) can be used to improve the lubricity of the top coat. In one embodiment, the molybdenum disulfide may be included in an amount of 0.5 to 15 parts by weight, relative to 100 parts by weight of the fluorine-based resin. When the fluorine-based resin is contained in the above range, the dispersibility can be made excellent, and the lubricity of the top coat layer and the non-stick property that food materials do not stick to the surface of the top coat layer can be made excellent. For example, the fluorine-based resin may be contained in an amount of 3 to 15 parts by weight.

The phosphate ester compound can improve the durability of the top coat layer and the adhesion to the base material. The phosphate ester compound may be one containing one or more of a hydroxyl group and a carboxyl group.

In one embodiment, the phosphate ester compound is contained in an amount of 1 to 15 parts by weight based on 100 parts by weight of the fluororesin. When the phosphate ester compound is contained in the above range, the durability and adhesion of the top coat layer can be excellent, and the viscosity of the top coat agent can be prevented from excessively increasing. If the phosphate ester-based compound is included in an amount of less than 1 part by weight, the adhesion of the top coating layer may be reduced, and if the phosphate ester-based compound is included in an amount of more than 15 parts by weight, the durability of the top coating layer may be reduced. For example, the phosphate ester compound may be contained in an amount of 1 to 8 parts by weight.

In one embodiment, the top coating agent may further include 0.5 to 5 parts by weight of germanium oxide with respect to 100 parts by weight of the fluorine-based resin. The germanium oxide can be used for improving the interlayer adhesion of the top coating of the invention. If the germanium oxide is contained in an amount of less than 0.5 parts by weight, the adhesion of the top coat layer of the present invention may be reduced, and if the germanium oxide is contained in an amount of more than 5 parts by weight, the miscibility of the top coat agent may be reduced, thereby deteriorating the smoothness and appearance. For example, it may contain 1 to 3 parts by weight of germanium oxide.

In one embodiment, the germanium oxide may have an average particle size of 0.1 μm to 20 μm. Within the above range, the dispersibility and miscibility can be excellent, and the interlayer adhesion of the top coat layer can be excellent.

In one embodiment, the germanium oxide and the phosphate compound may be included in a weight ratio of 1: 1 to 1: 5. When the germanium oxide and the phosphate compound are contained in the above weight ratio range, the top coat agent can be made excellent in mixability and workability, interlayer adhesion and durability of the top coat layer, and smoothness and appearance of the top coat layer. For example, germanium oxide and a phosphate compound may be included in a weight ratio of 1: 2 to 1: 4.

In one embodiment, the molybdenum disulfide may have an average particle size of 1 μm to 80 μm. Within the above range, the dispersibility and the mixability can be excellent.

In one embodiment, the top coating agent may further include a solvent, and the solvent may include one or more of water, alcohol having 1 to 10 carbon atoms, toluene, xylene, diisobutyl ketone, methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, 1-methoxy-2-propanol, ethanol, ethylene glycol butyl ether, cyclohexane, N-butyl acetate, N-methylpyrrolidone, dimethylformamide, ethyl acetate, acetone, methyl acetate, isobutyl acetate, isopropyl acetate, and dimethyl carbonate. In one embodiment, the alcohol having 1 to 10 carbon atoms may include one or more of methanol, ethanol, propanol, isopropanol, n-butanol, and isobutanol.

The solvent may be included in an amount of 10 to 500 parts by weight, based on 100 parts by weight of the fluorine-based resin. When the solvent is contained in the above range, the dispersibility and the workability of the components of the top coating agent can be made excellent.

In one embodiment, the top coating agent may further include additives such as a surfactant, a leveling agent, and an antifoaming agent. The additive may be included in an amount of 0.1 to 20 parts by weight, based on 100 parts by weight of the fluorine-based resin.

In one embodiment, the heat treatment may be performed at a temperature of 380 ℃ to 450 ℃. Under the above conditions, the primer layer, the color control layer, the thermochromic layer, and the topcoat layer can be hardened to provide excellent interlayer adhesion and durability.

In one embodiment, the thickness of the top coat layer may be 5 μm to 30 μm. In one embodiment, the thickness of the top coat layer can be measured from the surface of the thermochromic layer. Under the thickness condition, the durability of the top coat can be made excellent.

A cookware made by a method of making cookware comprising a thermochromic composite coating.

Another aspect of the present invention relates to a cooker manufactured by the manufacturing method of the cooker. In one embodiment, the cookware comprises: a metal substrate; a primer layer formed on one or more surfaces of the metal substrate, and containing a fluororesin; a color control layer formed on at least a portion of a surface of the primer layer; a thermochromic layer formed on at least a portion of a surface of the primer layer; and a top coat layer formed on the surface of the thermochromic layer, wherein the top coat layer is formed by a top coat agent, the top coat agent comprises 100 parts by weight of fluorine-based resin, 10-50 parts by weight of alkoxysilane compound, 5-50 parts by weight of first pigment, 0.5-15 parts by weight of molybdenum disulfide and 1-15 parts by weight of phosphate compound, the color adjusting layer is formed by a color adjusting coat agent, the color adjusting coat agent comprises a matrix resin and a color adjusting pigment, the thermochromic layer is formed by a thermochromic coat agent, the thermochromic coat agent comprises a thermochromic compound and a color changing pigment, the color adjusting pigment comprises titanium oxide, and the color changing pigment comprises iron oxide red.

The top coating agent may further include 0.5 to 5 parts by weight of germanium oxide with respect to 100 parts by weight of the fluorine-based resin, and the germanium oxide and the phosphate compound may be included in a weight ratio of 1: 1 to 1: 5.

The primer agent, the top coating agent, and the toning coating agent and the thermochromic layer coating agent constituting the primer layer may be applied with the components and contents as described above, and the description thereof will be omitted.

Modes for carrying out the invention

Hereinafter, the structure and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. However, the following examples are only for the purpose of facilitating understanding of the present invention, and the scope of the present invention is not limited to the following examples.

Hereinafter, the structure and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. However, these embodiments are merely provided as preferred examples of the present invention, and the present invention should not be construed as being limited thereto in any sense. Those skilled in the art to which the present invention pertains can sufficiently derive the contents not described herein, and thus, the description thereof will be omitted.

Examples and comparative examples.

The components used in the examples and comparative examples were as follows:

a first primer agent and a second primer agent.

(A) Fluorine-based resin: polytetrafluoroethylene and tetrafluoroethylene-hexafluoropropylene copolymer are used;

(B) a second pigment: perylene red (first primer) and ferromanganese black (second primer) were used;

(C) using a carboxyl group-containing phosphate compound;

(D) germanium oxide with an average particle size of 10 μm is used;

(E) additive: surfactants and defoamers are used;

(F) distilled water was used as a solvent.

A top coating agent.

(A) Fluorine-based resin: polytetrafluoroethylene and tetrafluoroethylene-hexafluoropropylene copolymer are used;

(B) alkoxysilane compound: glycidyl ether oxypropyl triethoxysilane is used;

(C) a first pigment: black manganese iron was used;

(D) molybdenum disulfide is used;

(E) using a carboxyl group-containing phosphate compound;

(F) germanium oxide with an average particle size of 10 μm is used;

(G) additive: surfactants and defoamers are used;

(H) distilled water was used as a solvent.

Examples 1 to 2 and comparative examples 1 to 6.

(1) Forming a primer layer: after degreasing one surface of a metal substrate (stainless steel), a pretreatment was performed by blasting with 60 Mesh alumina. Then, the first primer agent and the second primer agent were prepared by changing only the kind of the second pigment with the components and the contents described in table 1 below. After a first primer agent is coated on the pretreated surface of the metal substrate by using a sprayer to form a first primer layer, a second primer agent is coated on the edge of the surface of the first primer layer by using the sprayer, and the second primer layer is formed after the second primer agent is dried at the temperature of 90-100 ℃. The sum of the thicknesses of the first primer layer and the second primer layer is 12-15 mu m.

(2) Forming a color adjusting layer and a thermochromic layer: a toning coating agent comprising 100 parts by weight of a matrix resin (polyphenylene sulfide) and 30 parts by weight of a toning pigment (titanium dioxide) is applied to a part of the surface on which the second primer layer is formed, thereby forming a toning layer (specific pattern) having a thickness of 5 to 10 μm. Then, a thermochromic compound (Ag) containing 100 parts by weight was applied to the central portion of the surface of the second primer layer₂HgI₄) And 15 parts by weight of a color-changing pigment (iron oxide red) to form a 5-10 μm thick thermochromic layer.

(3) Forming a top coating and carrying out heat treatment: a top coating agent containing the components and contents shown in the following table 2 was prepared by a general method and applied on the surfaces of the color-adjusting layer, the thermochromic layer, and the second primer layer, and then heat-treated at a temperature of 430 to 440 ℃ to form a top coating layer having a thickness of 12 to 15 μm, thereby manufacturing a cooker (wok).

[ Table 1]

[ Table 2]

Method for evaluating physical properties

The physical properties of the composite coatings of examples 1 to 2 and comparative examples 1 to 6 were evaluated according to the following items, and the results are shown in table 3.

(1) Appearance: the composite coatings of examples and comparative examples were visually observed for the occurrence of cracks in appearance and evaluated according to the following 3 criteria (very good: no cracks occurred, Δ: some cracks occurred, and X: severe cracks occurred).

(2) Evaluation of corrosion resistance: the cookware of the examples and comparative examples was immersed in a 5% NaCl solution at 35 ℃ for 100 hours in accordance with JIS K54009.1 and then taken out, and the corrosion state of the coating films of the thermochromic composite coatings of the examples and comparative examples was observed and evaluated by the following three criteria (very good: no corrosion of the coating film, Δ: partial corrosion occurred, X: severe corrosion occurred).

(3) Pencil hardness: the measurement was carried out in accordance with JIS K5600-5-4.

(4) Evaluation of adhesion: for the composite coatings of the examples and comparative examples, the adhesion was evaluated by a cross-cut test in accordance with JIS K5400. The number of crosscuts that were not peeled off compared to the total number of crosscuts (100) is shown.

(5) Evaluation of antifouling Property: 20ml of soy sauce was dropped onto the surface of the cookware of the examples and comparative examples on which the composite coating was formed, and heated at a temperature of 200 ℃ to stick the soy sauce thereon. Then, the antifouling property was evaluated by the convenience in removing the contaminants on the surface of the composite coating layer using a water-soaked cloth (very good: easy to remove contaminants; Δ: long time required to remove contaminants; X: hardly removed contaminants although removed for a long time).

(6) Evaluation of abrasion resistance: the surfaces of the composite coatings formed on the cookware in the examples and comparative examples were evaluated by confirming the damage of the coating after rotating 15000 times at a load of GS-17 and 3kg and a speed of 60rpm using a taber abrasion tester (excellent: no damage occurred; Δ: a part of damage of the coating, and X: a large part of damage of the coating).

[ Table 3]

Fig. 3 is a photograph of the cooker manufactured according to example 1, and fig. 4 is a photograph of the cooker manufactured according to example 1 after heating. Referring to fig. 3 and 4, in the case of the embodiment of the present invention, although the thermochromic layer is not visible because no discoloration occurs at normal temperature, when the cooker is heated to a predetermined temperature or more, the discoloration (pattern) of the thermochromic layer appears, and it is understood that the heated state of the cooker can be easily recognized.

Further, referring to the results of table 3, it is understood that the thermochromic composite coatings of examples 1 to 2 using the composite coating layer of the present invention are excellent in abrasion resistance and adhesion between coatings, and excellent in antifouling property, and thus are easy to wash and manage, and have excellent non-stick property in which foodstuffs do not stick to the surface of the composite coating layer during cooking. On the contrary, in the case where comparative examples 1 to 6 of the present invention were not used, it was found that the appearance, abrasion resistance, adhesion, or stain resistance were reduced as compared with examples 1 to 2.

Those skilled in the art can easily implement simple modifications or variations of the present invention, which are considered to be included in the scope of the present invention.