JP2008154659A - Cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooker capable of improving wear resistance without increasing thickness considerably. <P>SOLUTION: A heat resistant coat 11 is formed on the surface of a base material, and diamond particles 15 are added as additive materials to the heat resistant coat 11 to prepare a pre-coat material 14. By this pre-coat material 14, at least one of cooking metal members represented by a heating panel for heating a cooking pan and materials to be cooked in the pan is formed. Thus, in the cooker equipped with the cooking pan, the heating panel, and the like, waste of coating and processes can be eliminated to obtain stable dimensional accuracy for a press molded product, and improve wear resistance without increasing the thickness considerably. Also, especially in the cooking pan, delivery of heat to the materials to be cooked from a heat resistance coat surface is made smooth to bring about an excellent cooking result. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cooking pot and a cooker that improves the wear resistance of a cooking metal member typified by a heating plate for heating an object to be cooked in the pot.

  2. Description of the Related Art Conventionally, a rice cooker as a cooker that is widely marketed to the public is represented by a cooking pan that is detachably provided, and a heating plate that is installed on a lid so as to cover the top surface of the pan and heats the food to be cooked. Cooking metal parts are used.

  Among these, the base of the pan is formed of a simple substance of aluminum or a composite material such as a laminate of aluminum and stainless steel or a laminate of aluminum, stainless steel and copper.

  These metal pans are usually treated with a heat-resistant coat such as a fluororesin coat on the inner surface to prevent the rice that is to be cooked from sticking strongly, improving the non-stickiness to rice I am letting.

  In addition, the heating plate that heats the object to be cooked is usually made of a metal such as stainless steel, and if necessary, heat-resistant coating such as fluororesin coating is treated on one or both sides to improve non-stickiness. Some have taken the structure which demonstrates the far-infrared effect and contributes to the improvement of a taste.

  Thus, when both the pan, the heating plate, etc. process the heat-resistant coating on the surface of the base material, as a first means, first, after pressing the metal base material into the shape of a pan, a heating plate, etc., the base material surface There are those that paint.

  As an example, after aluminum and stainless clad material is press-molded into a pan shape so that the inner surface is aluminum, aluminum is blasted, and then a liquid paint primer is applied and dried, followed by liquid or There is a method in which a fluororesin coating material is applied and baked to treat the fluororesin coat on the inner surface of the pan (see, for example, Patent Document 1).

  Also, as a second means, a metal material before press forming is subjected to a coating process using a technique such as roll coating or spin coating, and after preparing a coated substrate in advance, this is press molded. There are things that mold pots.

  As an example, an aluminum flat plate is etched with sodium hydroxide and fine irregularities are formed on the surface, and then an alumite treatment is performed. Then, a fluororesin coat is applied onto the flat plate by spin coating and fired. Some base materials are produced and press-molded into a pan or the like.

  Here, considering the basic performance as a fluororesin coat, it is important to ensure the non-stickiness of the rice, but when considering in more detail from the point of view of actual use, inside the pot of the rice cooker Assuming that the fluorine resin coat is placed in a highly worn environment, such as the load that the rice is strongly pressed against the fluororesin coat when sharpening the rice, and the rubbing load caused by a wearable cleaning tool such as nylon scrubbing when washing the pan There must be.

  In general, as a means of improving the abrasion resistance of a fluororesin coat used for frying pans, a technique such as adding a large amount of inorganic fillers such as ceramic particles to the top coat to improve the hardness of the top coat is taken. (See, for example, Patent Document 2). However, it is difficult to adopt the same technique in heat resistant coats such as cooking pots from the viewpoint of non-adhesiveness and ensuring the visibility of the water level display part.

  Therefore, as a means to improve the abrasion resistance of the fluororesin coat as a heat resistant coat in rice cooking pots etc., the wear resistance is improved by increasing the film thickness by increasing the thickness of the top coat as much as possible. However, as a method for increasing the film thickness, it has been necessary to apply a fluororesin powder coating to the limit or to increase the thickness of the fluororesin coat.

Usually, a fluororesin coat having a thickness of about 30 to 50 μm can be made about 100 μm by increasing the thickness, and an improvement in wear resistance can be expected according to the thickness.
JP 09-194196 A JP 2001-218684 A

  However, the conventional configuration has the following problems. That is, when heat-resistant coating is processed on a pan or a heating plate, there are a post-coating method for coating after press molding and a pre-coating method for pre-coating on a substrate before press molding.

  However, in the former case, liquid paint is spray-coated after press molding or powder paint is powder-coated. However, due to the nature of the coating, 100% coating efficiency is not obtained, and considerable paint is used. Will be thrown away without being applied to the molding.

  In actual coating, the coating efficiency is about 30 to 50% by ordinary liquid coating or powder coating, and even when electrostatic coating is performed, the coating efficiency is about 50 to 70%. Not only will it be wasted, it will also take time to dispose of the paint.

  In particular, when it is desired to increase the film thickness in consideration of wear resistance, the film can be formed relatively easily by powder coating, but on the other hand, waste of paint increases.

  Furthermore, in the case of a heat-resistant coat such as a fluororesin coat, it is usually necessary to perform baking at a high temperature of about 400 ° C. after the coating is completed. Failures often occur.

  In addition, when stainless steel is used as the base material and the heat-resistant coating is treated on one side, oxidation of the stainless steel surface on the non-painted surface is promoted by the high temperature during firing, resulting in an oxide film, and the appearance of the so-called temper color. Cause serious problems. For this reason, it is necessary to remove the oxide film by a wet technique such as pickling or electropolishing or a physical technique such as buffing, and not only a complicated process is required, but also during the oxide film removal process, Problems such as scratches may occur.

  When processing a heat-resistant coat on a pan or a heating plate, the second method is press molding of a pre-coating material that is pre-coated on a base material before press molding. According to this method, there is little waste of the paint and there is no need to fire after press molding, so that stable dimensional accuracy can be obtained. If the oxide film is removed, there is an advantage that it is not necessary to perform complicated processing after press molding.

  However, it is assumed that the heat-resistant coat treated on the surface is placed in a high wear environment, such as a rubbing load by a cleaning tool with abrasion due to nylon scrubbing etc. in actual use or routine care etc. There must be.

  As mentioned above, if you want to give the heat-resistant coating of pans and heating plates high non-stickiness and wear resistance, it is necessary to apply a thick film of fluororesin coating that does not contain additives such as ceramics as much as possible. is there.

  In the case of spin coating generally used for pre-coating, since it is applied with a liquid paint, in consideration of foaming failure due to outgassing at the time of baking of the paint, a thick film like powder coating is achieved with one or two layers of coating. It is not easy.

  Moreover, the material used for heat-resistant coats, such as a fluororesin, is expensive, and when considering mass production of the rice cooker which is an industrial product, it is desirable to suppress the usage amount as much as possible and to reduce the thickness.

  In order to keep the thickness of the heat-resistant coat thin, it is possible to add a large amount of a hard material to the top coat. However, if an additive is added to the top coat to the extent that it is effective for improving the wear resistance, As described above, the non-adhesiveness is deteriorated or the durability is adversely affected, so that the function is not sufficiently performed.

  In the case of a fluororesin coat painted on a pan or the like, since the fluororesin coat itself has a strong water repellency, bubbles of water vapor generated when water is put into the pan and heated are very difficult to reach from the surface of the fluororesin coat. There is a tendency to grow greatly without detachment. For this reason, heat is not smoothly transferred to the object to be cooked in the pan, and good convection is not easily generated, which may cause problems in cooking results.

  The present invention solves the above-mentioned conventional problems, eliminates waste of paint and processes, obtains stable dimensional accuracy in a press-molded product, suppresses damage during press molding, and involves a large thickness. It is an object of the present invention to provide a cooking device equipped with a cooking pan, a heating plate, etc. that can improve the wear resistance. In particular, the purpose of the pan is to smoothly transfer heat from the heat-resistant coating surface to the object to be cooked, and to provide good cooking results.

  In order to solve the conventional problems, the cooker of the present invention forms a heat-resistant coat on the surface of the base material, and adds diamond particles as an additive to the heat-resistant coat to produce a precoat material, The pre-coating material forms at least one cooking metal member represented by a cooking plate and a heating plate for heating an object to be cooked in the pan.

  This eliminates the waste of paint and processes, provides stable dimensional accuracy for press-molded products, and enables cooking pans, heating plates, etc. that can improve wear resistance without increasing the thickness of the film. A prepared cooker can be provided. In particular, in a cooking pan, heat is smoothly transferred from the heat-resistant coating surface to the food to be cooked, and a good cooking result is obtained.

  The cooker of the present invention can improve the wear resistance without increasing the thickness of the cooked metal member, and in particular, in a cooking pan, heat from the heat-resistant coated surface to the object to be cooked. Smooth delivery and good cooking results.

  In the first invention, a heat-resistant coat is formed on the surface of a base material, and diamond particles are added as an additive to the heat-resistant coat to prepare a pre-coat material. By using this pre-coat material, a cooking pot and pan The cooking device has at least one cooking metal member typified by a heating plate for heating the cooking object inside. This eliminates the waste of paint and processes, provides stable dimensional accuracy for press-molded products, and enables cooking pans, heating plates, etc. that can improve wear resistance without increasing the thickness of the film. A prepared cooker can be provided. In particular, in a cooking pan, heat is smoothly transferred from the heat-resistant coating surface to the food to be cooked, and a good cooking result is obtained.

  In the second invention, in particular, in the first invention, the base material is disk-shaped, so that spin coating by a spin coater can be performed, and a precoat material having a uniform film thickness can be efficiently produced. Because of its shape, it can be easily processed into a cooking pan or a heating plate having a circumferential shape.

  In the third invention, in particular, in the second invention, when the precoat material is processed into a pan shape by providing the heat-resistant coat to which diamond particles are added only at the center of the disk-shaped substrate, the diamond particles The heat-resistant coating layer to which is added will be placed only on the bottom of the pan, and the presence of diamond particles on the bottom of the pan that is strongly heated during cooking will cause the diamond particles to become boiling nuclei and serve as a heat release point. As a result of facilitating the formation of fine bubbles during heating, good convection can be produced in the food to be cooked in the pan, resulting in good cooking results. Further, in this case, since there is no heat-resistant coating layer to which diamond particles are added in the vicinity of the side surface of the pan, there is an advantage that the non-adhesiveness of the side surface portion is not deteriorated or the material cost can be saved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 and 2 illustrate a rice cooker as a cooker according to Embodiment 1 of the present invention.

  As shown in FIG. 1, the cooker body 1 detachably stores a cooking pan 2, and is provided with heating means 3 made of a heater so as to come into contact with the bottom of the pan 2 so that the pan 2 is directly heated. It is composed. The lid 5 covering the upper opening of the pan 2 is openable and closable, and an inner lid 6 is detachably installed on the inner surface.

  The pan bottom temperature detection sensor 4 is provided facing the outer bottom portion of the pan 2 and detects the temperature of the pan 2, and its output is input to the heating control board 7. The heating control board 7 is configured to execute the cooking and heat retaining process by program control by the microcomputer based on an input from the operation unit 8 having a microcomputer or the like. The lid 5 is provided with a steam cap 9.

  Here, the cooking pan 2 is made by pressing a 1.5 mm-thick aluminum base material into a pan shape, and the inner surface is pretreated with a fluororesin coat as a heat resistant coat. Yes.

  Hereinafter, a method for producing the aluminum pan subjected to the fluororesin coating treatment will be described with reference to FIG.

  First, a base material 10 in which an aluminum material is punched into a predetermined size is prepared, and this is etched with caustic soda to provide irregularities 12 on the surface, and then anodized to a thickness of about 0.1 μm. The alumite layer 13 is provided to improve the corrosion resistance.

  Next, this base material 10 is placed on a spin coater, and fluororesin coating treatment (heat-resistant coating 11 treatment) is performed. At this time, polytetrafluoroethylene = perfluoroalkylvinylether ( In addition to adhesive resin, carbon black pigment, glitter material, and diamond particles 15 having an average particle diameter of 3 μm are added to a fluororesin mainly composed of PFA), and spin coating is performed to obtain a film thickness of about 30 μm. A baking treatment was performed at 20 ° C. for 20 minutes.

  After processing the precoat material 14 produced as described above into a pan shape by press molding, if necessary, a water level line is provided on the side of the pan by stamping or the like, and then the anodizing process is performed on the outer surface of the pan to prepare the pan 2. Completed.

  At this time, the performance of the fluororesin coat varies as shown in Table 1 depending on the amount of diamond contained in the fluororesin coat film.

  In Table 1, * 1 compares the number of reciprocations until the base material is exposed by applying a load of 1 kg to a commercially available nylon scrub with abrasive particles, and x is equivalent to the standard. , △ is 1.5 to 2.0 times the standard durability, ◯ is 2.1 to 5.0 times the standard durability, and ◎ is a durability exceeding 5 times.

  * 2 is determined by the weight of the rice remaining on the surface of the fluororesin coat without falling from the pan 2 when the rice 2 is cooked, and the pan 2 is turned upside down after cooking, Indicates that 50% or more remains than the standard, Δ indicates that 20% or more remains than the standard, and ◯ indicates that the level remains equivalent to the standard.

  Diamond is the substance with the highest Mohs hardness in minerals, withstands high temperatures and is highly stable against acids and alkalis, so it can be exposed to high temperatures during cooking, rice sticks and various seasonings. It is a suitable material for improving the wear resistance by adding to the fluororesin coat.

  In actual use, when the pan 2 is washed, there is a phenomenon that the fluororesin coat surface is rubbed with a commercially available nylon scourer, and the fluororesin coat is worn out and deteriorated. The wear action due to is greatly involved. In general, the abrasive contained in nylon scrubs is alumina particles. In this embodiment, diamond having a hardness higher than that of alumina particles is used, so that high wear resistance is obtained for nylon scrubs. It is what was done.

  Here, as shown in (Table 1), paying attention to the amount of diamond in the fluororesin coat, there is a possibility that sufficient wear resistance cannot be expected if it is less than 0.3 wt%, and if it exceeds 5%, the non-cooking of rice Since the adhesiveness is deteriorated and the whitening of the appearance is conspicuous, it is desirable to add 0.3 to 5 wt% of diamond particles.

  Next, Table 2 shows the results of examining the corrosion resistance and wear resistance of the fluororesin coat in which the average particle diameter of diamond added to the fluororesin coat is changed. The amount of diamond added at this time was 1 wt%.

  (Table 2) discloses the corrosion resistance test results when the fluororesin coat thickness is 30 μm. This is a case where the prepared pan is filled with 2% salt water and 1% citric acid mixed aqueous solution at 60 ° C. for 30 minutes. This is a confirmation of the corrosion resistance when kept warm for days.

  In (Table 2), ○ and × indicate judgment criteria, ○ indicates no abnormality, and × indicates the occurrence of blisters.

  From Table 2, it was confirmed that if the average particle diameter of diamond is in the range of 0.5 to 10 μm, good corrosion resistance and wear resistance can be ensured. A range is desirable.

  In the present embodiment, the presence of the diamond particles 15 in the fluororesin coat provides the effect of improving the wear resistance as described above, and the diamond particles 15 present in the fluororesin coat Although it becomes a boiling core, many fine bubbles are generated during cooking, and as a result of generating good convection, there is also an effect of giving good cooking results. This point will be outlined below.

  Fluorine resin has low thermal conductivity, is a strong hydrophobic substance, and has high water repellency, so if you put water in a pan coated with fluororesin and heat it, the bubbles generated by boiling will not easily come off the surface. As a result of this increase, this hindered heat transfer and hindered convection, resulting in problems with cooking results.

  In order to improve this point, it is considered that a hydrophilic substance is originally added to the fluororesin coat to lower the water repellency. However, when a hydrophilic substance is added, the non-adhesiveness is lowered. There is also concern about the adverse effects of

  On the other hand, diamond is a hydrophobic substance, and it has a good affinity with a fluororesin, and there is little possibility of adverse effects such as deterioration of non-adhesiveness, dropping from the surface, and water absorption.

  In addition, the thermal conductivity of the fluororesin is extremely low, whereas the thermal conductivity of the diamond added in the present embodiment is as extremely high as about 2000 W / m · k, which is a metal having a high thermal conductivity. About 9 times that of aluminum and about 5 times that of copper.

  Therefore, since diamond has extremely high thermal conductivity, especially when diamond particles are used as additive particles, the diamond particles become boiling nuclei and become heat release points, which tend to generate fine bubbles during heating. It is possible to produce a good convection to the food to be cooked in the pan and to provide a good cooking result.

  In the present embodiment, since only one fluororesin coat is provided, this first fluororesin coat layer corresponds to the top coat. Moreover, although the cooking pan 2 has been described as a cooking metal member, the inner lid 6 in FIG. 1 can be provided with a fluororesin coat as a heat resistant coat. Furthermore, although cooking rice was demonstrated as cooking, it is applicable not only to this but the whole cooking.

(Embodiment 2)
FIG. 3 shows the base material of the cooking device in Embodiment 2 of the present invention. This is because the basic configuration as a cooking device is the same as in the first embodiment. The description is omitted.

  In the present embodiment, the pan 2 is formed by pressing a 1.5 mm thick aluminum as a base material into a pan shape in the same manner as in the first embodiment. The heat resistant coating 16 made of a fluororesin coating is processed.

  Hereinafter, a method for producing the aluminum pan subjected to the fluororesin coating will be described with reference to FIG.

  First, in the same manner as in the first embodiment, a base aluminum material is punched into a disk shape of a predetermined size, and this is etched with caustic soda to provide irregularities on the surface, and then anodized to 0.1 μm. A thick anodized layer is provided to improve the corrosion resistance.

  Next, this disk is applied to a spin coater, and a fluororesin coating treatment is carried out as the first layer coat 17. At this time, the liquid fluororesin coating is a fluorine mainly composed of polytetrafluoroethylene (hereinafter referred to as PTFE). An adhesive resin, a carbon black pigment, and a bright material were added to the resin, spin-coated so that the film thickness was about 20 μm, and then dried at 150 ° C. for 20 minutes.

  Thereafter, a liquid fluororesin paint mainly composed of PFA added with 1 wt% of diamond particles 15 having an average particle diameter of 3.5 μm is spin-coated so as to have a film thickness of 10 μm, and baked at 380 ° C. for 20 minutes. A precoat material 14 having a film thickness of 30 μm and diamond particles 15 added to the topcoat 18 was produced.

  After the pre-coating material 14 produced as described above is processed into a pan shape by press molding, a water level line is provided on the side of the pan by stamping as necessary, and then the pan is completed by anodizing the outer surface of the pan. I let you.

  The fluororesin coat 16 of the pan in the present embodiment is a two-layer coat, and it is easier to make the film thickness thicker than the pan of the single-layer coat shown in the first embodiment, and the durability is further improved. In addition, since the expensive diamond particles 15 are not contained in the first coat 17, the cost can be reduced.

  Further, in the present embodiment, since diamond is added to the top coat 18, effects such as improvement of wear resistance can be obtained as in the first embodiment, and it exists on the surface layer inside the top coat. Particles become boiling nuclei and a lot of fine bubbles are generated during cooking, and as a result of generating good convection, there is also an effect of providing good cooking results. Furthermore, there is no particular problem even if the diamond particles 15 are added to the first coat 17.

  In Embodiments 1 and 2, diamond is used as the additive material particle, but there is no problem even if a ceramic material such as alumina or silica, carbon, a bright material, mica, or the like is used in combination. As described above, it is important to determine the amount of these additives after examining the non-stickiness and appearance of rice.

(Embodiment 3)
FIG. 4 shows a pot of a cooking device in Embodiment 3 of the present invention. This is because the basic configuration as a cooking device is the same as in the first embodiment. The description is omitted.

  In the present embodiment, the pan 2 is formed by pressing a 1.5 mm thick aluminum base material into a pan shape in the same manner as in the first embodiment. Two layers of the fluororesin coat are treated, and one side of the fluororesin coat is treated on the side portion.

  Hereinafter, a method for manufacturing the aluminum pan subjected to the fluororesin coating treatment will be described with reference to FIG.

  As in the first embodiment, first, the aluminum material of the base material is punched into a disk shape of a predetermined size, this is etched with caustic soda to provide irregularities on the surface, and then anodized to 0.1 μm. A thick anodized layer is provided to improve the corrosion resistance.

  Next, this disk is placed on a spin coater, and a fluororesin coating treatment is carried out as a first layer coat. At this time, the liquid fluororesin coating is a fluorine mainly composed of polytetrafluoroethylene (hereinafter referred to as PTFE). An adhesive resin, a carbon black pigment, and a bright material were added to the resin, spin-coated so that the film thickness was about 20 μm, and then dried at 150 ° C. for 20 minutes.

  After that, the part which becomes the side part after press molding is masked, and the film thickness is made of a powdery fluororesin coating material in which 1 wt% of diamond particles having an average particle diameter of 3.5 μm are microencapsulated into PFA powder having an average particle diameter of 20 μm. Powder coating was performed so as to be 10 μm, and baking was performed at 380 ° C. for 20 minutes.

  Accordingly, the precoat material in the present embodiment has a two-layer coat of 30 μm in the vicinity of the center 20 of the disk that becomes the bottom of the pan after press molding, and a single-layer coat of 20 μm in the peripheral part 21 of the disk. Diamond particles are added only to the coat.

  After the pre-coating material prepared as described above is processed into a pan shape by press molding, if necessary, a water level line is provided on the side of the pan by stamping, etc., and then an anodizing process is performed on the outer surface of the pan to complete the pan. It was.

  In the present embodiment, since there is a fluororesin coat in which diamond particles are added only in the vicinity of the pan bottom 22, the diamond particles become boiling nuclei due to the presence of diamond particles on the bottom of the pan that is strongly heated during cooking. As a result, it becomes a point of release of heat and tends to generate fine bubbles during heating. As a result, good convection is generated in the cooking object in the pan, and a good cooking result can be obtained.

  Further, in this case, since there is no top coat layer to which diamond particles are added in the vicinity of the pan side surface 23, there is an advantage that the non-adhesiveness of the side surface portion is not deteriorated or the material cost can be saved.

  In the present embodiment, diamond is used as the additive particles, but there is no problem even if a ceramic material such as alumina or silica, carbon, a glittering material, mica, or the like is used in combination, as described above. It is important to determine the amount of these additives after examining the non-stickiness and appearance of rice.

  In addition, in Embodiment 1-3, although illustrated about the pan made from aluminum, it applies also to the pan etc. which are press-molded from the clad material of aluminum and stainless steel mainly used for an electromagnetic induction heating type cooking device. There is no particular problem.

(Embodiment 4)
5 and 6 illustrate a rice cooker as a cooker according to Embodiment 4 of the present invention.

  As shown in FIG. 5, the cooker main body 31 detachably stores a cooking pan 32, and opposes the bottom and side bottoms of the pan 32 and a heating plate 36 that heats the cooking object in the pan 32. Electromagnetic induction heating coils 33 and 42 are provided in the respective sections, and the pan 32 and the heating plate 36 are configured to be heated by electromagnetic induction heating. A magnetic shielding ferrite 34 is provided outside the electromagnetic induction heating coil 33. The lid 35 covers the upper opening of the pan 32 so as to be freely opened and closed, and a heating plate 36 is detachably installed on the inner surface of the lid 35.

  The pan bottom temperature detection sensor 38 is provided facing the outer bottom portion of the pan 32 and detects the temperature of the pan 32, and its output is input to the heating control board 39. The heating control board 39 includes a microcomputer, an inverter circuit that supplies high-frequency current to the electromagnetic induction heating coils 33 and 34, operates while being cooled by the board cooling fan 37, and is based on an input from the operation unit 40. Thus, the cooking and heat retaining steps are executed by program control by a microcomputer. The lid 35 is provided with a steam cap 41.

  The cooker according to the present embodiment generates heat by heating the heating plate 36 by electromagnetic induction heating. The heating plate 36 is made of a ferrite-based stainless steel having a thickness of 0.5 mm, and heat-resistant on one side of the ferrite-based stainless steel. After the pre-coating of the property coat, this is pressed to form the heating plate 36.

  Hereinafter, a method for producing the heat-resistant coated stainless steel heating plate will be described with reference to FIG.

  First, after blasting one side of a rolled stainless steel plate 43, a solvent-based paint mainly composed of polyethersulfone (hereinafter referred to as PES) and polyamideimide (hereinafter referred to as PAI) is coated with carbon black, oxidized The coating material to which titanium is added is applied as a first-layer coating 44 by a roll coating method so as to have a thickness of 10 μm, and then dried at 150 ° C. for 20 minutes.

  Next, carbon black and titanium oxide are added to the solvent-based paint mainly composed of PES, and diamond particles having an average particle diameter of 3 μm are added so that 1 wt% diamond exists in the coating film after film formation, Moreover, the coating material which added PFA particle | grains so that 10 wt% PFA might exist in the coating film after film-forming was produced.

  This paint was applied as a top coat 45 by a roll coating method to a thickness of 10 μm, and then baked at 380 ° C. for 20 minutes. Therefore, diamond particles were added to the top coat 45 with a total film thickness of about 20 μm. A pre-coating roll material having a coat was prepared.

  In this state, an oxide film is formed on the unexposed stainless steel exposed surface 46 by heat treatment during baking of the heat resistant coating, and a gold or brown temper color appears.

  Since this oxide film not only deteriorates the appearance but also deteriorates the corrosion resistance, it is necessary to remove this oxide film, so that the roll material is immersed in a phosphoric acid / sulfuric acid mixed solution or hydrochloric acid, or is physically buffed. Although it is necessary to sufficiently remove the oxide film by the treatment, when baking is performed in a non-oxidizing furnace, the oxide film cannot be formed, so that pickling or buffing is unnecessary.

  The pre-coated roll material produced as described above can be continuously formed on the heating plate 36 by press working such as transfer molding.

  The pre-coated roll material thus produced is processed into the shape of the heating plate 36 by press molding, but the coated surface is processed so as to face the pan 32 and, if necessary, attached accessories such as a handle are completed. To do.

  From the heat-resistant coated surface processed on the surface facing the pan 32 of the heating plate 36 produced in the present embodiment, far-infrared rays having a wavelength of 3 to 15 μm are emitted with an emissivity of 88%. The far-red emissivity of the stainless steel mirror-finished surface facing the lid 35 is 2%.

  Therefore, the heating plate 36 provided in the cooking device in the present embodiment having the above-described configuration has an overwhelmingly high heat emissivity from the surface facing the pan 32, and heat is efficiently heated. However, heat radiation from the heating plate 36 to the lid 35 is low, and an unnecessary temperature rise of the lid 35 can be prevented.

  In addition, when the wear resistance was confirmed, it was confirmed that the fluororesin coat of the heating plate 36 in this embodiment has a wear resistance twice or more that of a normal fluororesin coat having the same film thickness. This was the effect of diamond particles added in the fluororesin coat.

  Therefore, the heating plate 36 in the present embodiment has high wear resistance, is resistant to scratches due to care, and has high durability, so that the effect of far-red radiation can be maintained at the same initial level for a long period.

  Further, since it is a pre-coating material, there is little waste of paint, there is no complicated process such as painting and oxide film removal after pressing, and there is no baking treatment after pressing, so high dimensional accuracy can be obtained.

  In the present embodiment, the blasting process is used to improve the adhesion between the stainless steel and the heat-resistant coating, but it can be replaced with a chemical conversion process.

  As described above, the cooker according to the present invention can improve the wear resistance without increasing the thickness of the cooked metal member, and particularly in the cooking pan, from the heat-resistant coating surface. Since it smoothly delivers heat to the object to be cooked and brings about good cooking results, it can be used as a rice cooker, for example, a cooking utensil having a top plate with a heat-resistant coat formed on the surface of a substrate. Etc. are also useful.

Sectional drawing of the cooker in Embodiment 1 of this invention (A) Perspective view of base material for processing pan of same cooker (b) Enlarged sectional view of precoat material for processing pan of same cooker The expanded sectional view of the precoat material of the cooking appliance in Embodiment 2 of the present invention (A) Perspective view of precoat material of cooker in embodiment 3 of the present invention (b) Broken sectional view showing a pan of the cooker Sectional drawing of the cooker in Embodiment 4 of this invention (A) Perspective view of stainless steel roll material processed into heating plate of same cooker (b) Enlarged sectional view of precoat material on heating plate of same cooker

Explanation of symbols

2, 32 Pot 10 Base material 11, 16 Heat resistant coat 15 Diamond particle 36 Heating plate

Claims (3)

A heat-resistant coat is formed on the surface of the base material, and diamond particles are added to the heat-resistant coat as an additive to prepare a pre-coating material. With this pre-coating material, the cooking pan and the food to be cooked in the pan are prepared. A cooker in which at least one cooking metal member represented by a heating plate to be heated is formed. The cooking device according to claim 1, wherein the base material has a disk shape. The cooker according to claim 2, wherein the heat-resistant coat to which the diamond particles are added is provided only at the center of the disc-shaped substrate.