JP2010040171A - Top plate for cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a top plate for a cooker, which keeps a heat-resistant resin layer from deteriorating even if the top plate is heated to high temperatures, thus preventing a sensor from being stained by an adhesive, and maintaining a good appearance. <P>SOLUTION: The top plate (1) is used for a cooker having an electromagnetic heating device. A porous light-blocking layer (3) comprising an inorganic pigment and glass is formed on the surface of a low-expansion transparent crystallized glass plate (2). A heat-resistant resin layer (4) is formed at least on the electromagnetic heating portion of the light-blocking layer. The heat-resistant resin layer contains a silane coupling agent. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a top plate of a cooker provided with an electromagnetic heating device.

  An infrared heating device such as a radiant heater or a high-power type halogen heater, or an electromagnetic heating device such as an induction heater (IH) is used for the heating system of the electric cooker.

  Conventionally, a dark crystallized glass plate that blocks visible light and transmits infrared light has been used as a top plate of a cooking appliance equipped with an infrared heating device. The blocking of the visible light is to make the heating device parts difficult to see and to reduce the strong visible light emission from the halogen heater so as not to be dazzled. In addition, since this kind of cooking device can visually recognize the red-heated heater part through the dark-colored crystallized glass plate, it is used as a mark at the time of heating.

  On the other hand, a cooker equipped with an electromagnetic heating device does not generate visible light unlike an infrared heating device, and therefore does not light a heater part that serves as a mark during heating. Therefore, in this type of cooker, electromagnetic heating power is separately displayed using a light emitting diode or the like. Some of these heating power display bodies are provided on the side of the cooking device, but those which are installed near the heating unit and can confirm the heating power through the top plate are becoming mainstream. However, the light emitted from the light emitting diode is not as strong as the light emitted from the conventional infrared heater. For this reason, the dark-colored crystallized glass plate has a drawback that the light of the diode is not conspicuous and is difficult to see.

  In view of this, a transparent crystallized glass plate is used for the top plate of the electromagnetic heating device in which a light shielding layer is provided except for a portion where a light emitting diode is displayed so that the internal structure of the cooker is not seen. For example, Patent Document 1 proposes a top plate on which a porous light-shielding layer made of an inorganic pigment and glass is formed as a top plate for a cooker provided with this light-shielding layer. In such a top plate, since the light shielding layer is made porous by using a glass with a small amount of inorganic pigment, the occurrence of cracks in the light shielding layer due to the difference in expansion from the transparent crystallized glass plate is prevented. Can do.

  However, when a porous light shielding layer is employed, there is a problem that adhesion marks of a temperature sensor (thermocouple) attached to an electromagnetic heating portion on the back surface of the top plate are conspicuous, which is not preferable in appearance.

  In order to solve this problem, in Patent Document 2 below, a porous light shielding layer composed of an inorganic pigment and glass is formed on the surface of a low expansion transparent crystallized glass plate, and a heat resistant resin is formed on at least the electromagnetic heating portion of the light shielding layer. A cooker top plate with layers formed has been proposed. In such a top plate, the presence of the heat-resistant resin layer can prevent the adhesive of the sensor from flowing into the gap between the light shielding layers, and a good appearance can be obtained.

By the way, when the temperature of the top plate rises, the adhesive of the temperature sensor softens and spreads easily. On the other hand, in recent years, due to the improvement in performance of the electromagnetic heating device, the heating temperature of the electromagnetic heating cooker has dramatically increased, and the top plate has also increased to a higher temperature than before. When the top plate reaches a high temperature (for example, 200 ° C. or higher), the heat-resistant resin layer is likely to deteriorate (crack generation). As a result, the softened temperature sensor adhesive penetrates into the light shielding layer through the gap between the heat-resistant resin layers, and this is seen as a stain when viewed from the use surface, which is not preferable in appearance. A new problem has occurred.
Japanese Patent Laid-Open No. 10-273342 JP 2003-338360 A

  The present invention is for solving the problems of the prior art as described above, and even if the temperature of the top plate rises to a high temperature, the heat-resistant resin layer does not deteriorate, and the stain due to the adhesive of the sensor An object of the present invention is to provide a top plate for a cooker that does not generate a good appearance.

  The invention according to claim 1 is a top plate for a cooker used as a top plate of a cooker equipped with an electromagnetic heating device, and is a porous light-shielding made of an inorganic pigment and glass on the surface of a low expansion transparent crystallized glass plate. And a heat-resistant resin layer is formed on at least an electromagnetically heated portion of the light-shielding layer, and the heat-resistant resin layer contains a silane coupling agent. .

  The invention according to claim 2 is characterized in that the resin constituting the heat-resistant resin layer includes a polyimide resin, a polyamide resin, a fluorine resin, a silicone resin, or a composite thereof. It relates to the top plate for a cooker described.

  In the invention according to claim 3, the silane coupling agent is an epoxy silane coupling agent, an amino silane coupling agent, a ureido silane coupling agent, a methacryl silane coupling agent, a vinyl silane coupling agent, or a styryl silane coupling agent. The top plate for a cooker according to claim 1 or 2, comprising at least one of the following.

  The invention according to claim 4 is characterized in that in the heat-resistant resin layer, the resin constituting the heat-resistant resin layer and the silane coupling agent are in a mass ratio of 80: 1 to 13: 1. It is related with the top plate for cookers in any one of 1-3.

The invention according to claim 5 is characterized in that the low expansion transparent crystallized glass plate is made of crystallized glass having an average linear thermal expansion coefficient at 30 to 750 ° C. of −10 to + 30 × 10 ⁻⁷ / ° C. It is related with the top plate for cookers in any one of Claims 1-4.

  According to the invention according to claim 1, since the heat-resistant resin layer contains the silane coupling agent, the bonding of the three-dimensional network structure forming the resin is strengthened, and the top plate reaches a high temperature. In addition, the heat resistant resin layer can be prevented from deteriorating (occurrence of cracks). As a result, the adhesive of the temperature sensor that has been softened and spread at high temperature can be prevented from penetrating into the light shielding layer through the gaps in the heat-resistant resin layer, preventing the occurrence of stains and providing a good appearance. It can be set as the top plate for cookers to exhibit.

  According to the invention which concerns on Claim 2, since the resin which comprises a heat resistant resin layer contains a polyimide-type resin, a polyamide-type resin, a fluorine resin, a silicone resin, or those composites, heat resistance is higher. Thus, it is possible to more reliably prevent the heat resistant resin layer from being deteriorated. As a result, it is possible to more reliably prevent the adhesive of the temperature sensor softened and spread at high temperatures from penetrating through the gaps in the heat-resistant resin layer and into the light-shielding layer. It can be set as the top plate for cooking appliances which shows a beautiful appearance.

  According to the invention of claim 3, the silane coupling agent is an epoxy silane coupling agent, an amino silane coupling agent, a ureido silane coupling agent, a methacryl silane coupling agent, a vinyl silane coupling agent, or a styryl silane coupling agent. Since at least one of them is included, adhesion between the heat-resistant resin layer and the surface of the inorganic pigment particles of the light-shielding layer is improved, so that the heat-resistant resin layer can be more reliably prevented from peeling from the light-shielding layer. . As a result, it is possible to more reliably prevent the adhesive of the temperature sensor softened and spread at high temperatures from penetrating through the gaps in the heat-resistant resin layer and into the light-shielding layer. It can be set as the top plate for cooking appliances which shows a beautiful appearance.

  According to the invention which concerns on Claim 4, since the resin which comprises a heat resistant resin layer, and a silane coupling agent are 80: 1-13: 1 by mass ratio, the heat resistant resin layer is a strong heat resistant resin layer. And the deterioration of the heat-resistant resin layer can be more reliably prevented. As a result, it is possible to more reliably prevent the adhesive of the temperature sensor that has been softened and spread at high temperatures from penetrating into the light-shielding layer through the gaps in the heat-resistant resin layer. It can be set as the top plate for cooking appliances which shows a beautiful appearance.

According to the invention according to claim 5, the low expansion transparent crystallized glass plate is made of crystallized glass having an average linear thermal expansion coefficient at 30 to 750 ° C. of −10 to + 30 × 10 ⁻⁷ / ° C. Even if heating and cooling are repeated, the light-shielding layer and the heat-resistant resin layer can be prevented from peeling from the crystallized glass plate because the transparent crystallized glass plate has a lower expansion coefficient. As a result, it is possible to more reliably prevent the adhesive of the temperature sensor that has been softened and spread at high temperatures from penetrating into the light-shielding layer through the gaps in the heat-resistant resin layer. It can be set as the top plate for cooking appliances which shows a beautiful appearance.

  Hereinafter, a preferred embodiment of a top plate for a cooker according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a cooker top plate according to the present invention.

  As shown in FIG. 1, the top plate (1) for a cooking device according to the present invention has a light shielding layer (3) and a heat resistant resin layer (4) formed on the surface of a transparent crystallized glass plate (2).

The transparent crystallized glass plate (2) is preferably a colorless transparent low expansion crystallized glass, but a colored transparent crystallized glass may be used as long as the object of the present invention is achieved. Since the crystallized glass plate (2) is repeatedly heated and cooled, it is required to have low expansion, and the average linear thermal expansion coefficient at 30 to 750 ° C. is −10 to + 30 × 10 ⁻⁷ / ° C., particularly − It is desirable to use one in the range of 10 + 20 × 10 ⁻⁷ / ° C. If the thermal expansion coefficient is within the above range, the light shielding layer (3) and the heat-resistant resin layer (4) are peeled off from the crystallized glass plate (2) without being cracked due to a difference in expansion due to the temperature distribution inside the top plate during heating. Therefore, it is possible to prevent the adhesive of the temperature sensor softened and spread at a high temperature from penetrating into the light shielding layer (3) through the gap between the heat resistant resin layers (4). The top plate (1) for a cooker that prevents the occurrence of stains and exhibits a good appearance can be obtained. An example of crystallized glass that satisfies this condition is N-0 manufactured by Nippon Electric Glass Co., Ltd.

  The light shielding layer (3) is made of an inorganic pigment and glass. Moreover, it is porous in order to prevent crack generation due to a difference in expansion from the crystallized glass plate (2). For the formation of the light shielding layer (3), it is possible to use a forming material in which the ratio of the inorganic pigment powder and the glass powder is in the range of 5: 5 to 9: 1, preferably 5: 5 to 8: 2. preferable. If the ratio of the glass powder is 10% or more, the inorganic pigment powder can be firmly fixed to the crystallized glass plate (2), and if it is 50% or less, the glass powder can be densely sintered. And a porous membrane can be easily obtained.

Examples of the inorganic pigment _{powder, TiO 2, ZrO 2, ZrSiO} 4 other white pigments, Co-Al-Zn-based, Co-Al-Si-based, Co-Al-Ti-based blue pigments, Co-Al-Cr-based, Co-Ni-Ti-Zn green pigment, Ti-Sb-Cr, Ti-Ni yellow pigment, Co-Si red pigment, Ti-Fe-Zn, Fe-Zn, Fe-Ni -Cr-based, Zn-Fe-Cr-Al-based brown pigments, Cu-Cr-based, Cu-Cr-Fe-based, Cu-Cr-Mn-based black pigments can be used alone or in combination.

Examples of the glass powder include B ₂ O ₃ —SiO ₂ system, Na ₂ O—CaO—SiO ₂ system, Li ₂ O—Al ₂ O ₃ —SiO ₂ system, ZnO—Al ₂ O ₃ —P ₂ O ₅ system, and the like. Glass can be used.

  The thickness of the light shielding layer (3) is preferably 0.1 to 50 μm, particularly preferably 0.2 to 40 μm. If the thickness is 0.1 μm or more, it is possible to shield visible light to hide the heating device, and if it is 50 μm or less, it is possible to suppress an increase in film formation cost due to an increase in the number of printings and an increase in material cost. . Furthermore, although the top plate is remelted and recycled, the inorganic pigment contained in the coating becomes an impurity for the glass and causes the glass to be colored. However, if the film thickness is thin, coloring is difficult to occur.

  The light shielding layer (3) may be formed on the entire surface of the transparent crystallized glass plate (2), but an unformed portion may be provided as necessary. For example, an unformed portion for forming a light emitting diode display region can be provided around the heated portion.

Moreover, when using for the cooking appliance provided with not only an electromagnetic heating apparatus but an infrared heating apparatus, the printing density of the light shielding layer (3) of an infrared heating part can be made lower than that of an electromagnetic heating part, or from an electromagnetic heating part. It is also desirable to reduce the thickness of the light shielding layer (3). Further, in the infrared heating section, a raster layer (metallic gloss film) may be formed instead of the light shielding layer (3). That is, since the light shielding layer (3) is difficult to transmit infrared rays, it is necessary for infrared heating by reducing the printing density of the inorganic pigment layer in the infrared heating portion, reducing the film thickness, or forming a raster film. This is because an amount of infrared rays can be transmitted. The “print density” means a film formation (printing) area per unit area. For example, when the total area of the film forming portions per 1 cm ² of a certain area of the top plate is 0.5 cm ² , the printing density is 50%. The “printing density of the infrared heating portion” is the average printing density of the entire region corresponding to the infrared heating device of the cooker, and the “printing density of the electromagnetic heating portion” is the entire region corresponding to the electromagnetic heating device. Means average print density.

  When the printing density is lowered, it is preferable that the printing density is 30 to 80%, particularly 40 to 80% of the printing density of the electromagnetic heating portion. If the printing density of the infrared heating part is 30% or more of the electromagnetic heating part, it is possible to shield visible light to completely hide the heating device, and if the printing density is 80% or less, the infrared transmission amount is sufficient. High cooking performance can be obtained.

As a method for reducing the printing density of the light shielding layer (3) and ensuring a sufficient infrared ray transmission amount, for example, there is a method of providing a large number of apertures. When forming the apertures, it is desirable to uniformly distribute the apertures throughout the light shielding layer in the infrared heating portion. The size of each opening is preferably about 0.05 to 5 mm in diameter, particularly about 0.1 to 3 mm. Further, it is preferable to form about 5 to 500 holes, especially about 10 to 500 holes per 1 cm ² .

  When making the film thickness of the light shielding layer (3) thin, it is preferable to make the film thickness about 10 to 50%, particularly about 10 to 40% of the light shielding layer (3) of the electromagnetic heating portion. If it is 10% or more, the contrast with the surroundings does not increase, and it becomes difficult to stand out. Moreover, if it is 50% or less, infrared rays transmission amount will become large and sufficient cooking performance will be obtained.

  In the case of a raster film, those containing metal elements such as Au, Pt, Pd, Rh, Ru, Bi, Sn, Ni, Fe, Cr, Ti, Ca, Si, Mg, and composites thereof can be used. is there. In particular, those containing Au, Pd, Bi, Sn, Fe, Ti, etc. can be suitably used. The film thickness of the raster film is preferably 0.1 to 10 μm on average, and particularly preferably 0.1 to 5 μm.

  The heat resistant resin layer (4) is required to have heat resistance against high temperatures (for example, about 200 ° C. or higher). As the resin having heat resistance, a polyimide resin, an (aromatic) polyamide resin, a fluorine resin, a silicone resin or a composite thereof can be used as a main component, and in particular, a silicone resin can be used. preferable.

  The heat resistant resin layer (4) contains a silane coupling agent. By containing the silane coupling agent in the heat resistant resin layer, the bonding of the three-dimensional network structure forming the resin is strengthened, and even if the top plate reaches a high temperature, the heat resistant resin layer (4) is deteriorated (cracked). Occurrence) can be prevented. As a result, the adhesive of the temperature sensor that has softened and spreads at a high temperature can be prevented from penetrating into the light-shielding layer (3) through the gap between the heat-resistant resin layers (4), thereby preventing the occurrence of stains. And it can be set as the top plate (1) for cookers which exhibits a favorable external appearance.

  Examples of the silane coupling agent contained in the heat resistant resin layer (4) include an epoxy silane coupling agent, an amino silane coupling agent, a ureido silane coupling agent, a methacryl silane coupling agent, a vinyl silane coupling agent, and a styryl silane coupling agent. Of these, at least one of them is preferably used. As a result, adhesion between the heat-resistant resin layer (4) and the surface of the inorganic pigment particles of the light-shielding layer (3) is improved, so that the heat-resistant resin layer (4) is more reliably prevented from peeling from the light-shielding layer (3). Because it can be done. As a result, it is possible to more reliably prevent the adhesive of the temperature sensor that has been softened and spread at a high temperature from penetrating into the light-shielding layer (3) through the gap between the heat-resistant resin layers (4). It can be set as the top plate (1) for cookers which prevents that and exhibits a favorable external appearance.

  The heat-resistant resin layer (4) preferably has a blending ratio of the heat-resistant resin and the silane coupling agent constituting 80: 1 to 13: 1. When the mass ratio of the heat-resistant resin exceeds 80, it becomes difficult to prevent the heat-resistant resin layer (4) from being deteriorated when the temperature of the top plate exceeds 200 ° C., and the mass ratio of the heat-resistant resin is lower than 13. Since the heat-resistant resin layer (4) becomes too hard, cracks may occur due to expansion and contraction due to overheating and cooling, and the stain caused by penetration of the sensor adhesive into the light-shielding layer (3) is prevented. This is because it becomes difficult.

  The heat-resistant resin layer (4) may be colorless and colored, but may contain a heat-resistant organic pigment or an inorganic pigment in order to adjust the appearance of the light-shielding layer (3). By containing the pigment and the silane coupling agent in the heat-resistant resin layer (4), in addition to strengthening the three-dimensional network structure of the resin, the resin and the pigment can be more firmly bonded. Even if a pigment is contained in (4), deterioration of the heat-resistant resin layer (4) can be prevented.

  The film thickness of the heat resistant resin layer (4) is preferably 0.01 to 50 μm. If it is 0.01 μm or more, it is possible to prevent the penetration of the adhesive. Moreover, if it is 50 micrometers or less, the problem of a cost increase and the problem that reduction | restoration of glass will occur at the time of remelting of collection | recovery glass will not arise easily.

  The heat-resistant resin layer (4) may be applied only to the electromagnetic heating portion, but may be applied to other portions. For example, when an adhesive is used to attach the top plate to the cooker body, the adhesion mark may appear in the same manner as the electromagnetic heating part, but by forming a heat resistant resin layer (4) on that part as well Good appearance can be obtained. In order to make the color tone of the entire light shielding layer (3) uniform, the heat resistant resin layer (4) is desirably applied to the entire surface of the light shielding layer (3) excluding the infrared heating portion. In addition, when the heat resistant resin layer (4) has high heat resistance and can withstand high temperatures during infrared heating, a better appearance can be obtained by applying the heat resistant resin layer (4) to the infrared heating portion.

  The top plate (1) for a cooking device of the present invention is attached to the cooking device so that the light shielding layer (3) and the heat-resistant resin layer (4) face the cooking device body side, that is, the electromagnetic heating device (and the infrared heating device). used. The attachment to a cooking appliance is performed by adhere | attaching and fixing to a support frame of the top plate provided in the cooking appliance main body using a silicone resin.

  In addition, a decorative coating can be printed and formed on the upper surface of the cooker as necessary for improving the design and displaying the heater position. The decorative coating can also be formed using a material composed of an inorganic pigment powder and a glass powder, but it is necessary to form a strong and smooth film so that it does not peel off even when rubbed and it is difficult for dirt to adhere. Therefore, it is important to select a decorative coating material having a higher glass content than the light shielding layer material. Specifically, the glass content in the decorative coating material is preferably 50% or more on a mass basis. Moreover, the same material as what is used for a light shielding layer (3) can be used for glass powder and inorganic pigment powder.

  The top plate (1) for a cooker of the present invention is produced as follows. First, a low expansion transparent crystallized glass plate (2) formed and processed to a predetermined size is prepared. A mixed powder of an inorganic pigment and glass powder is made into a paste. Next, a paste is printed on the surface of the crystallized glass plate by a method such as screen printing, and after drying, is fired to form a light shielding layer (3) on the transparent crystallized glass plate. Further, a heat-resistant paint containing a silane coupling agent to be a heat-resistant resin layer (4) is applied on the light-shielding layer (3) and dried, preferably dried and then baked, for the cooking device of the present invention. A top plate (1) can be obtained.

  In addition, as a drying method of the coating film which consists of heat-resistant coating materials, there exists a method of drying about 10 minutes-1 hour at 50-100 degreeC, for example using a hot air dryer. If the drying is insufficient, the solvent remaining in the coating film is rapidly vaporized at the time of firing, resulting in pinhole-shaped coating film defects. Further, if the heat-resistant paint is applied and left to dry for a certain period of time, appropriate fluidity can be maintained for a certain period of time, so that the surface of the coating film can be smoothed.

  Firing is performed, for example, in an electric furnace. The firing temperature is 200 to 400 ° C., preferably 250 to 350 ° C., and the firing time is 10 minutes to 1 hour, preferably 30 minutes to 1 hour. In the firing step, if the firing temperature is 400 ° C. or higher, the heat resistant resin is thermally decomposed, which is not preferable.

  Moreover, when making the film thickness of the heat-resistant resin layer (4) thick, it may be formed by applying the heat-resistant paint once, but it is preferable to form it by applying the heat-resistant resin layer a plurality of times. In the case of applying a plurality of times, it is preferable to perform drying and baking for each application because pinhole-like coating film defects due to remaining volatile components are less likely to occur.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited only to these Examples.

(Examples 1-5)
First, a commercially available frit composed of a Cu—Cr—Mn black inorganic pigment and a B ₂ O ₃ —SiO ₂ glass powder (SiO ₂ 63%, B ₂ O ₃ 19%) was mixed at 65:35, A paste was prepared by adding a resin and an organic solvent. Next, this paste is applied to a transparent crystallized glass plate N-0 (average linear thermal expansion coefficient of 30 to 750 ° C. −4 × 10 ⁻⁷ / ° C.) made by Nippon Electric Glass Co., Ltd. so that the film thickness becomes 5 μm. Screen printed. Subsequently, the paste was dried at 100 to 150 ° C. for 10 to 20 minutes, and then baked at 850 ° C. for 30 minutes to form a light shielding layer.

  Subsequently, a heat-resistant coating material prepared by mixing a silicone resin and a silane coupling agent in the ratio shown in Table 1 and adding an organic solvent was applied over the entire surface of the light shielding layer by screen printing. In addition, KR-300 (made by Shin-Etsu Chemical Co., Ltd.) was used as the silicone resin, and γ-aminopropyltriethoxysilane was used as the silane coupling agent. Next, it baked at 300 degreeC for 30 minute (s), the heat resistant resin layer was formed, and the top plate of Examples 1-5 was produced.

(Comparative example)
A top plate was prepared in the same manner as in Examples 1 to 5 except that the silane coupling agent was not contained in the heat resistant resin layer, and was used as a comparative example.

(Heat resistance test)
The top plate produced in this manner was incorporated into an electromagnetic heating device, and the cycle in which hot water was continuously boiled in a pan for 30 minutes and then cooled for 15 minutes was repeated three times. The temperature of the top plate was 200 ° C. during boiling of hot water. After cooling, the adhesive stain of the sensor was visually observed and evaluated as ◎ if the stain could not be confirmed at all, ○ slightly if the stain was not noticeable, ○ as if it was not worrisome, and × if the stain could be confirmed . The results are shown in Table 1.

  From the results shown in Table 1, in Examples 1 to 3, no stain was confirmed, and in Examples 4 and 5, the stain was not noticeable, whereas in the Comparative Example, the stain was confirmed. You can see that

(Examples 6 to 10)
A top plate was prepared in the same manner as in Examples 1 to 5 except that 3-glycidoxypropyltrimethoxysilane was used as the silane coupling agent in the ratio shown in Table 2, and the top plates of Examples 6 to 10 were prepared. A similar heat resistance test was conducted. The results are shown in Table 2.

  From the results in Table 2, in Examples 6 to 8, no stain was confirmed, and in Examples 9 and 10, the stain was not noticeable. As a silane coupling agent, γ-aminopropyltrimethyl in Table 1 was used. It turns out that it is the same result as the case where ethoxysilane is used.

  The present invention can be suitably used as a cooker top plate used in an electromagnetic heating cooker.

It is explanatory drawing which shows the top plate which concerns on this invention.

Explanation of symbols

1 Top plate for cooker 2 Transparent crystallized glass plate 3 Light-shielding layer 4 Heat-resistant resin layer

Claims (5)

A top plate for a cooking device used as a top plate of a cooking device equipped with an electromagnetic heating device, wherein a porous light shielding layer made of an inorganic pigment and glass is formed on the surface of a low expansion transparent crystallized glass plate, and the light shielding layer A heat-resistant resin layer is formed on at least the electromagnetic heating part,
The top plate for a cooking device, wherein the heat-resistant resin layer contains a silane coupling agent.   The top plate for a cooking device according to claim 1, wherein the resin constituting the heat resistant resin layer includes a polyimide resin, a polyamide resin, a fluorine resin, a silicone resin, or a composite thereof.   The silane coupling agent includes at least one of an epoxy silane coupling agent, an amino silane coupling agent, a ureido silane coupling agent, a methacryl silane coupling agent, a vinyl silane coupling agent, and a styryl silane coupling agent. The top plate for a cooker according to claim 1 or 2, wherein   4. The heat resistant resin layer according to claim 1, wherein the resin constituting the heat resistant resin layer and the silane coupling agent are in a mass ratio of 80: 1 to 13: 1. Top plate for cooking utensils. The low-expansion transparent crystallized glass plate is made of crystallized glass having an average linear thermal expansion coefficient at 30 to 750 ° C of -10 to +30 x 10 ^-7 / ° C. Crab top plate according to crab.