JPH07289A - Heating and cooking device and its production - Google Patents

Abstract

PURPOSE:To provide the heating and cooking device having a cooking surface which permits easy use of a metallic spatula and the process for production of such device by improving the wear resistance and corrosion resistance of the heating and cooking device, such as hot plate or electric pan. CONSTITUTION:This heating and cooking device has the cooking surface formed by subjecting a surface 12 of die cast molded articles of an aluminum alloy to be used as the cooking surface to a sandblasting treatment, then thermally spraying and adhering a thermal spraying material prepared by combining chromium carbide with nickel chromium thereon by using a plasma device to form a thermally sprayed layer 13 in such a manner that the center line average height attains <=10mum, then by forming a primer layer 14 and a fluororesin layer 15 thereon and baking these layers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking surface which enables the use of a metal spatula for a heating cooker such as a hot plate and an electric pan.

[0002]

2. Description of the Related Art The cooking surface of a conventional cooking device such as a hot plate or an electric pan is disclosed in, for example, Japanese Patent Application Laid-Open No. 4-341221 in order to improve wear resistance to a metal spatula. It had a composition. The details will be described with reference to FIG. 7. After the unevenness 2 is formed on the surface of the cooking surface 1 of the aluminum alloy die-cast molded product in advance and the surface is roughened by sandblasting or the like, the alumina-based spray material is plasma-sprayed. A thermal sprayed layer 3 was formed by thermal spraying and adhering, and an undercoat layer 4 of the fluororesin paint and an overcoat layer 5 of the fluororesin paint were finished thereon and baked. In addition, in order to improve wear resistance at high temperatures, the fluororesin of the top coat layer 5 is made of polytetrafluoroethylene (hereinafter referred to as PTF).
A mixture of E resin), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (hereinafter abbreviated as PFA resin), and potassium titanate fiber was used. As another method, a material in which titanium oxide is mixed with aluminum oxide is used as the thermal spray material.

That is, even after the unevenness 2 is formed on the surface of the cooking surface 1 and the thermal sprayed layer 3 is formed thereon, and the fluororesin undercoat layer 4 and the overcoat layer 5 are formed on the thermal sprayed layer 3,
The surface of the cooking surface 1 has a shape of irregularities 6. Therefore, as shown in FIG. 8, the use of a metal spatula causes some damage to the crests 7 of the irregularities 6, but no damage to the valleys 8 and the presence of the surface 9 of the fluororesin. Conventionally, fluororesin softens around 230 ° C, but PTFE is
By using a mixture of PFA resin and potassium titanate fiber as the resin, abrasion resistance at high temperature was improved. Furthermore, by using a material in which titanium oxide is mixed with aluminum oxide as the thermal spray material, the adhesiveness of the thermal spray layer 3 is improved,
Adhesion with the fluororesin undercoat layer 4 applied thereon is good, and therefore wear resistance is good.

[0004]

However, when a metal spatula is used for cooking, the fluororesin undercoat layer 4 on the cooking surface 1 is used.
When the unevenness 6 is provided on the top coat layer 5, the fluororesin is peeled off less than when the unevenness 6 is not provided. Further, the peeling of the fluororesin becomes faster when the metal spatula is used as compared with when the resin spatula is used at the time of cooking. Therefore, when a metal spatula was used for a long time, the cooked product was sticky to the peeled portion of the fluororesin. Furthermore, by mixing PFA resin and potassium titanate fiber with PTFE resin as a fluororesin, wear resistance at high temperature is improved and heating cooker can be heated, but when using a metal spatula, the fluororesin layer peels off. Therefore, the use of a metal spatula is not preferable. Further, even when a titanium oxide is mixed with an alumina-based ceramic material as a thermal spray material, the thermal spray layer 3
The adhesion of the fluororesin undercoat layer 4 is improved, and the abrasion resistance of the fluororesin undercoat layer 4 and the overcoat layer 5 is also improved, but there is a problem that the fluororesin layer is immediately peeled off when a metal spatula is used for a long time. .

The present invention has been made to solve the above problems, and an object of the present invention is to provide a heating cooker having a cooking surface that can be easily used with a metal spatula and has a long service life.

[0006]

In order to achieve the above object, the means of the invention according to claim 1 is to spray a thermal spray material composed of chromium carbide and nickel chromium onto the surface of a metal material serving as a cooking surface. After that, a heating cooker having a cooking surface, which was coated with a fluororesin paint and baked, was prepared.

According to the second aspect of the present invention, a fluorine resin containing polytetrafluoroethylene as a main component is used.

According to a third aspect of the present invention, there is provided a heating cooker having a cooking surface in which a coating film surface is subjected to polishing treatment after the thermal spray material is sprayed and attached.

According to a fourth aspect of the present invention, there is provided a heating cooker having a cooking surface which has been subjected to a sealing treatment after the thermal spraying material has been sprayed and attached.

According to a fifth aspect of the present invention, there is provided a manufacturing method in which the cooking surface is heated in advance before the thermal spray material is sprayed and attached to the cooking surface.

[0011]

According to the above-mentioned means of the invention of claim 1, since the thermal spraying material which is sprayed and adhered to the aluminum alloy die-cast molded article to be the cooking surface uses the thermal spraying material in which chromium carbide and nickel chromium are compounded, the alumina is used. The adhesive strength between the cooking surface and the thermal spray material and the adhesive strength between the particles of the thermal spray material are stronger than the thermal spray adhesion of the system thermal spray material, and the adhesion of the coating becomes stronger. Further, the adhesion between the fluororesin layer and the thermal sprayed layer applied thereon is stronger than that of the alumina-based thermal spraying material by thermal spraying, and the abrasion resistance of the fluororesin layer is improved.

According to the second aspect of the invention, the PTFE
By using a fluororesin whose main component is resin,
The adhesiveness between the thermal sprayed layer of the thermal sprayed material composed of chromium carbide and nickel chromium and the fluororesin layer is improved, and the abrasion resistance of the fluororesin layer is improved.

The results of comparison with a fluororesin in which potassium titanate and PFA resin were used in combination with the PTFE resin will be described below. In the abrasion test of a metal spatula at a high temperature of 230 ° C., the PTFE resin was peeled off from the fluororesin. There is almost no, and the surface of fluorine exists as it is. For this reason, the stickiness of the cooked food is partially observed, but the stickiness of the cooked food of the whole plate as in the conventional case is not seen, and the metal spatula can be easily used.

According to the third aspect of the present invention, the cooking surface is formed by polishing the surface of the sprayed layer deposited by spraying, so that the shape of the particles on the surface of the sprayed layer is not sharp.
It becomes smooth. Then, the adhesion with the fluororesin applied thereon is improved, and the wear resistance is improved.

According to a fourth aspect of the present invention, the cooking surface is subjected to a sealing treatment after the thermal spray material is sprayed and attached. This makes it possible to prevent corrosion of aluminum. That is, in practical cooking, when chlorine or the like penetrates from the pinhole of the fluororesin layer and reaches the sprayed layer, the chlorine or the like that reaches the sprayed layer in the conventional product reaches the aluminum of the cooking surface through the opening of the sprayed layer, Corroded aluminum. Since the use of a metal spatula may increase the number of pinholes in the fluororesin, a sealing treatment was performed. As a result, chlorine that has penetrated to the surface of the sprayed layer will not penetrate to aluminum,
Not corroded. Therefore, the service life of the cooking surface is greatly extended.

According to the means of the fifth aspect of the present invention, since the cooking surface before thermal spraying is preheated and the thermal spray material is sprayed and adhered thereto, the particles of the thermal spray layer are fine and smooth. That is, when the temperature of the cooking surface is low, the particles of the sprayed material that have been sprayed and attached are immediately cooled, so that the crystals of the particles are large and have an acute angle. On the contrary, when the temperature of the cooking surface is high, the particles of the sprayed material sprayed and adhered slowly cool, and the crystals become fine and smooth. Here, if the particles of the sprayed layer are finer and smoother, the better the adhesion to the fluororesin applied thereon, the better the abrasion resistance of the fluororesin layer.

With the above-mentioned means, the cooking surface of the heating cooker can be easily used with a metal spatula and can be used for a long time.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below with reference to the drawings.

(Embodiment 1) FIGS. 1 and 2 are sectional views showing a first embodiment of the present invention. In FIG. 1, reference numeral 11 denotes a hot plate of aluminum alloy die cast, which serves as a cooking surface of the plate 11. The surface 12 and the metal spatula are easy to use, and a film layer is formed. The surface 12 is shown in detail in FIG. 2. On the surface 12 serving as the cooking surface of the plate 11, a thermal spray material composed of chromium carbide and nickel chromium is thermally sprayed and adhered to form a thermal spray layer 13. A primer layer 14 and a fluororesin layer 15 are formed on the sprayed layer 13.

Next, a manufacturing method for forming a film on the surface 12 of the plate 11 will be described. Plate 1 shown in FIG.
Although No. 1 is manufactured by die casting of an aluminum alloy, the surface 12 serving as a cooking surface has a shape without unevenness. Then, the surface 12 is subjected to sandblasting (# 36, alumina oxide) to roughen the surface 12.

After that, a plasma spraying apparatus was used to remove Cr.
A composite material having ₃ C ₂ 75%, NiCr 25%, and a particle size of 45-5 μm is deposited by thermal spraying, and the thermal sprayed layer 13 is formed to have a film thickness of 10 to 30 μm. Here, the distance between the gun of the plasma device and the plate is about 10 cm. The surface roughness of the thermal sprayed layer 13 is set so that the center line average roughness Ra is 10 μm or less. Next, a thin coat of the primer layer 14 is applied 120
Fluorine resin layer 1 after pre-drying at ~ 150 ° C for 10 minutes
5 is applied and baked at 380 ° C. for 20 minutes.

In the plate 11 thus constructed, the adhesion strength between the cooking surface 12 and the thermal spray layer 13 and between the thermal spray layer 13 and the fluororesin layer 15 is remarkably increased, and the abrasion resistance of the fluororesin layer 15 is improved. Therefore, when a wear test is performed on a metal spatula, compared with the case where a conventional Al ₂ O ₃ —TiO ₂ is used as a thermal spray material, the conventional one has several hundreds of scratches, whereas the conventional one has a remarkable damage. The thing did not get scratched even after 10,000 times.

(Embodiment 2) As shown in FIG. 3, the surface 21 of the plate 20 having no unevenness is sandblasted as in the embodiment 1, and then the thermal sprayed layer 1 is formed by plasma spraying.
3 is formed, and the primer layer 14 is thinly applied to 120-
After preliminary drying at 150 ° C. for 10 minutes, a fluororesin of polytetrafluoroethylene is applied and baked at 380 ° C. for 20 minutes to form a fluororesin layer 15.

In the plate 20 thus constructed,
The adhesiveness between the sprayed layer 13 and the fluororesin layer 15 is better than when other fluororesins are used, and the abrasion resistance is further improved.

(Embodiment 3) As shown in FIG. 4, the surface 26 of the plate 25 having no irregularities is subjected to sandblasting to form a sprayed layer. Is preheated to about 100 ° C. Then, in the same manner as in Example 1, a plasma spraying apparatus is used to spray deposit a Cr ₃ C ₂ / NiCr composite material to form a sprayed layer 27. Next, the primer layer 14 is thinly applied and predried at 120 to 150 ° C. for 10 minutes, and then the fluororesin layer 15 is applied and baked at 380 ° C. for 20 minutes.

In the plate 25 thus constructed,
Since the temperature of the surface 26 of the plate 25 at the time of thermal spray deposition is high, the thermal spray deposited particles cool slowly, and the crystal of the particles becomes fine and smooth. Further, the surface roughness of the sprayed layer 27 becomes small. This improves the adhesion between the sprayed layer 27 and the fluororesin layer 15 and improves the wear resistance of the fluororesin layer 15.

(Embodiment 4) As shown in FIG. 5, after the surface 31 of the plate 30 is sandblasted, a Cr ₃ C ₂ / NiCr composite material is deposited by thermal spraying using a plasma spraying device, The sprayed layer 32 is formed. Then, after that, the surface of the sprayed layer 32 is buffed so that the surface roughness of the sprayed layer 32 is the center line roughness and Ra is about 5 μm. Next, the primer layer 14 is thinly applied and predried at 120 to 150 ° C. for 10 minutes, and then the fluororesin layer 15 is applied and baked at 380 ° C. for 20 minutes.

In the plate 30 constructed as above,
By buffing the surface of the sprayed layer 32,
The shape of the surface is smooth without any sharp edges. Further, the surface roughness of the sprayed layer 32 is reduced. This improves the adhesion between the thermal spray layer 32 and the fluororesin layer 15, and improves the wear resistance of the fluororesin layer 15.

(Embodiment 5) As shown in FIG.
After the surface 36 of No. 5 is sandblasted, a plasma spraying apparatus is used to spray deposit a composite material of Cr ₃ C ₂ / NiCr to form a sprayed layer 37, and then a sprayed layer 37.
A sealing process is performed in which the opening 38 is impregnated with a heat-resistant resin coating 39 having good permeability. Next, the primer layer 14 is thinly applied and predried at 120 to 150 ° C. for 10 minutes, and then the fluororesin layer 15 is applied and baked at 380 ° C. for 20 minutes.

In the plate 35 thus constructed,
For example, chlorine, etc., during the practical cooking is not included in the fluorine resin layer 15
When it passes through the pinhole of No. 1, it permeates many openings of the sprayed layer to reach the surface of the plate and corrodes aluminum as a material of the plate. However, since the sealing treatment is performed in this embodiment, the heat-resistant resin coating material 39 covers the opening 38 and the surface of the thermal spray layer 37 and hardly passes through the thermal spray layer 37. Therefore, the aluminum alloy of the material of the plate 35 is less likely to be corroded. Further, when a metal spatula was used, the fluororesin layer 15 was easily damaged and corroded, but it can be improved by performing a sealing treatment. Therefore, the corrosion resistance is improved and the service life of the plate is greatly extended.

With the above construction, even if a metal spatula is used, a cooking surface of a heating cooker having excellent wear resistance and corrosion resistance can be obtained.

[0032]

As is apparent from the above description, according to the present invention, the wear resistance and the corrosion resistance against the use of a metal spatula are improved, the metal spatula is easily used, and a long-life performance is obtained. As a result, it is possible to provide an excellent heating cooker that enables efficient and smooth work during cooking.

[Brief description of drawings]

FIG. 1 is a sectional view of a plate of a hot plate showing a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the cooking surface of the hot plate showing the first embodiment of the present invention.

FIG. 3 is an enlarged sectional view of a cooking surface of a hot plate showing a second embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a cooking surface of a hot plate showing a third embodiment of the present invention.

FIG. 5 is an enlarged sectional view of a cooking surface of a hot plate showing a fourth embodiment of the present invention.

FIG. 6 is an enlarged sectional view of a cooking surface of a hot plate showing a fifth embodiment of the present invention.

FIG. 7 is an enlarged sectional view of a cooking surface of a conventional heating cooker.

FIG. 8 is an enlarged sectional view of a cooking surface of a conventional heating cooker.

[Explanation of symbols]

 11, 20, 25, 30, 35 Plate 12, 21, 26, 31, 36 Surface 13, 27, 32, 37 Thermal spray layer 14 Primer layer 15 Fluorine resin layer 38 Opening 39 Heat-resistant resin paint

Claims (5)

[Claims] 1. A heating cooker having a cooking surface prepared by depositing a thermal spraying material composed of chromium carbide and nickel chromium on the surface of a metallic material to be a cooking surface, and then applying a fluororesin coating and baking it. 2. The heating cooker according to claim 1, which has a cooking surface using a fluororesin containing polytetrafluoroethylene as a main component. 3. After the thermal spraying material has been sprayed on the cooking surface,
The coating surface has a cooking surface which has been subjected to polishing treatment.
The cooker described. 4. The heating cooker according to claim 1, further comprising a cooking surface that has been sealed after the thermal spray material has been attached to the cooking surface. 5. A heating cooker in which a metal material to be a cooking surface is heated in advance, and then a thermal spraying material composed of chromium carbide and nickel chromium is sprayed and adhered to the cooking surface, and then a fluororesin paint is applied and baked. Manufacturing method.