JP2009047406A - Top plate for cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a top plate for a cooker wherein stains caused by an adhesive such as silicone grease are hardly visible from a cooking surface side even when the top plate becomes an excessively high temperature state in use. <P>SOLUTION: The top plate for the cooker is constituted by forming an inorganic pigment layer on the surface of a transparent crystallization glass plate. An inorganic paint layer including silica is formed on the inorganic pigment layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a top plate for a cooker used for an infrared heating cooker, an electromagnetic heating (IH) cooker, a gas cooker or the like provided with a radiant heater or a halogen heater.

  In recent years, in addition to gas cookers that use conventional gas stoves, infrared cookers that use radiant heaters and halogen heaters as heat sources, and electromagnetic cookers that use IH as a heat source have been used as household and commercial cookers. ing. The top plate used in these cookers is a heat-resistant substrate made of a non-metallic material such as low thermal expansion glass, crystallized glass, or ceramics because of its excellent heat resistance, aesthetics, cleanability, etc. Is used.

An inorganic pigment layer composed of a low expansion glass powder and a pigment is provided on the back surface (the surface opposite to the cooking surface) of these cooker top plates as necessary for improving design and displaying the heater position. It is formed by printing (see, for example, Patent Document 1). Here, an adhesive such as silicon grease is used to attach a temperature sensor for acquiring temperature information for controlling each heat source to the back surface of the top plate for a cooker. At that time, in order to prevent the adhesive from penetrating into the inorganic pigment layer, for example, a top plate for a cooker in which a barrier layer such as a heat resistant resin layer is printed on the inorganic pigment layer has been proposed.
JP-A-7-61837

  When the top plate for a cooker is used, the heat-resistant resin layer is likely to be deteriorated when it is in an excessively high temperature state such as airing during cooking. Then, the adhesive such as silicon grease may pass through the deteriorated heat-resistant resin layer and soak into the voids of the inorganic pigment layer. As a result, the stain of the adhesive is conspicuous from the cooking surface side of the top plate for a cooker. A problem occurs.

  Accordingly, an object of the present invention is to provide a top plate for a cooking appliance in which a stain due to an adhesive such as silicon grease is not noticeable from the cooking surface side even when the temperature becomes excessively high during use.

  As a result of intensive studies to solve the above technical problems, the present inventors have made it more effective to penetrate the adhesive on the inorganic pigment layer in the top plate for a cooker having an inorganic pigment layer formed on the surface. The present inventors have found that the above problem can be solved by providing a barrier layer that can be prevented automatically, and propose the present invention.

  That is, the top plate for a cooking appliance of the present invention is characterized in that an inorganic pigment layer is formed on the surface of a transparent crystallized glass plate, and a silica-containing inorganic coating layer is formed on the inorganic pigment layer.

  A conventional cooker top plate made of crystallized glass has an inorganic pigment layer formed on the surface on the heating device side, and a barrier layer such as a heat-resistant resin layer is directly formed thereon. On the other hand, as shown in FIG. 1, the top plate for a cooker according to the present invention has a silica-containing inorganic coating layer 4 formed on an inorganic pigment layer 2 formed on the surface of a transparent crystallized glass plate 1. The silica-containing inorganic coating layer 4 has better heat resistance than the conventional heat-resistant resin layer. Therefore, even when it becomes an excessively high temperature state such as airing during cooking, the adhesive 6 such as silicon grease used for attaching the temperature sensor 5 is prevented from soaking into the inorganic pigment layer 2. can do. Thereby, there exists an effect that the stain | pollution | contamination of an adhesive agent is not conspicuous from the surface by the side of the cooking surface of the top plate for cookers.

  In the top plate for a cooker of the present invention, it is preferable that a heat-resistant paint layer is formed on the silica-containing inorganic paint layer.

  As shown in FIG. 2, the top plate for a cooking device of the present invention has a silica-containing inorganic coating layer 4 formed on an inorganic pigment layer 2 formed on the surface of a transparent crystallized glass plate 1, and further has a heat resistance thereon. The resin layer 3 is formed (the silica-containing inorganic coating layer 4 is formed between the inorganic pigment layer 2 formed on the surface of the transparent crystallized glass plate 1 and the heat-resistant resin layer 3). As a result, the adhesive 6 such as silicon grease used for attaching the temperature sensor 5 permeates the inorganic pigment layer 2 through the heat-resistant resin layer 3 deteriorated due to an excessively high temperature state such as emptying during cooking. Can be prevented. Thereby, there exists an effect that the stain | pollution | contamination of an adhesive agent is not conspicuous from the surface by the side of the cooking surface of the top plate for cookers. By setting it as such a structure, the effect which prevents adhesives, such as a silicone grease, permeating into an inorganic pigment layer can be improved further.

  In the cooker top plate of the present invention, the silica-containing inorganic coating layer is preferably a silica layer, a layer composed of a double oxide of silicon and zirconium, or a layer composed of a mixture of silicon oxide and zirconium oxide.

  In the cooker top plate of the present invention, the silica-containing inorganic coating layer preferably has a thickness of 0.03 to 1.5 μm.

  The top plate for a cooking device of the present invention is characterized in that an inorganic pigment layer is formed on the surface of a transparent crystallized glass plate, and a silica-containing inorganic coating layer is formed on the inorganic pigment layer.

  The transparent crystallized glass plate is preferably made of transparent crystallized glass in which β-quartz solid solution crystal is precipitated as a main crystal, from the viewpoint of a small thermal expansion coefficient and excellent thermal shock resistance.

The transparent crystallized glass preferably has a thermal expansion coefficient of −5 to + 15 × 10 ⁻⁷ / ° C. in a temperature range of 30 to 750 ° C. The crystallized glass having such a thermal expansion coefficient, in _{mass%, SiO 2 50~75%, Al} 2 O 3 10~30%, 0~8% MgO, BaO 0~8%, ZnO 0~10 _{%, Li 2 O 1~7%,} Na 2 O 0~7%, K 2 O 0~7%, TiO 2 1~5%, TiO 2 + ZrO 2 1~10%, P 2 O 5 0~10% It is preferably a crystallized glass containing a fining agent in a composition of 0.1 to 3% and having a β-quartz solid solution crystal precipitated therein.

Among them, in terms of _{mass%, SiO 2 55~70%, Al} 2 O 3 15~25%, 0~5% MgO, BaO 0~5%, 0~5% ZnO, Li 2 O 3~5%, Na ₂ O 0-2%, K ₂ O 0-2%, TiO ₂ 1.3-3%, TiO ₂ + ZrO ₂ 2-6%, P ₂ O ₅ 0-5%, fining agent 0.1-2% It is more preferable that it contains the following composition.

As the above fining _{agent, As 2 O 3, Sb 2} O 3, it is preferable to use at least one selected from SnO ₂ and Cl.

Further, as the transparent crystallized glass, in _{mass%, SiO 2 60~70%, Al} 2 O 3 14~28%, 0.1~2% MgO, CaO 0~2%, BaO 0~3%, ZnO 0 _{.1~3%, Li 2 O 2.5~5.5%} , Na 2 O 0.1~2%, K 2 O 0~1%, TiO 2 0~6%, ZrO 2 0~3%, V ₂ O ₅ 0.03~0.5%, containing a composition of PbO 0 to 3%, it precipitated a β- quartz solid solution crystals, dark crystallized glass appearance exhibiting black color also suitable.

  The inorganic pigment layer contains an inorganic pigment and glass. Here, the inorganic pigment layer is preferably porous, so that cracks caused by separation of the interface between the crystallized glass plate and the inorganic pigment layer and differences in the thermal expansion coefficients of the crystallized glass plate and the inorganic pigment layer can be obtained. It is possible to prevent problems such as the occurrence of In order to form a porous inorganic pigment layer, the ratio of the glass powder in the raw material powder containing the inorganic pigment and the glass powder is preferably 50% by mass or less. Further, in order to firmly fix the inorganic pigment layer to the transparent crystallized glass plate, the ratio of the glass powder is preferably 10% by mass or more.

Examples of inorganic pigment powder include white pigments such as TiO ₂ , ZrO ₂ , and ZrSiO ₄ ; blue pigments such as Co—Al—Zn, Co—Al—Si, and Co—Al—Ti; Co—Al—Cr Co-Ni-Ti-Zn-based green pigments; Ti-Sb-Cr-based, Ti-Ni-based yellow pigments; Co-Si-based red pigments; Ti-Fe-Zn-based, Fe-Zn-based Brown pigments such as Fe-Ni-Cr and Zn-Fe-Cr-Al; black pigments such as Cu-Cr, Cu-Cr-Fe, and Cu-Cr-Mn can be used.

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 inorganic pigment layer is preferably 0.1 to 5 μm, and more preferably 0.2 to 3 μm. When the thickness of the inorganic pigment layer is less than 0.1 μm, the visible light shielding for hiding the heating device is insufficient, which is not preferable in appearance. On the other hand, when the thickness of the inorganic pigment layer is larger than 5 μm, the film formation cost tends to increase due to an increase in the number of printings and an increase in material cost. In addition, when the top plate is remelted and recycled, the inorganic pigment contained in the coating becomes an impurity for the glass. Therefore, if the inorganic pigment layer becomes too thick, it tends to cause undue coloring in the recycled glass.

  In the top plate for a cooker of the present invention, a heat-resistant resin layer is formed on the silica-containing inorganic coating layer as necessary. As the heat-resistant resin layer, polyimide resin, polyamide resin, fluorine resin, and silicon resin can be used. These resins can be used alone or in combination of two or more. The heat-resistant resin layer preferably has a heat resistance of about 200 ° C. or higher.

  The thickness of the heat resistant resin layer is preferably 1 to 50 μm, and more preferably 2 to 30 μm. If the thickness of the heat-resistant resin layer is less than 1 μm, the adhesive easily penetrates into the inorganic pigment layer side, and if it exceeds 50 μm, peeling due to a difference in thermal expansion is likely to occur, resulting in an increase in cost. Moreover, there is a tendency that a problem of glass reduction occurs during remelting for recycling.

  In the top plate for a cooker of the present invention, the thickness of the silica-containing inorganic coating layer is preferably 0.03 to 1.5 μm, more preferably 0.05 to 1.2 μm, and 0.1 to 1 μm. More preferably. When the thickness of the silica-containing inorganic coating layer is less than 0.03 μm, a desired effect cannot be obtained with respect to prevention of stain of an adhesive such as silicon grease. On the other hand, even if the thickness of the silica-containing inorganic coating layer is larger than 1.5 μm, no further effect can be expected with respect to preventing the stain of the adhesive, which is not preferable from the viewpoints of economy and resource saving.

  Examples of the silica-containing inorganic coating layer include a silica layer, a layer made of a double oxide of silicon and zirconium, or a layer made of a mixture of silicon oxide and zirconium oxide.

  The silica layer is a layer containing silica as a main component, but may contain other components to be mixed during film formation or the like as long as the performance as a film is not impaired.

  As a technique for forming the silica layer, a technique in which a crystallized glass plate is immersed in a solution containing an alkoxysilane or a halogenated silane and then pulled out from the solution, that is, an immersion method is generally used. According to the dipping method, it is easy to form a silica layer having a desired thickness without unevenness. Examples of the solvent include lower alcohols such as methanol, ethanol and propanol, and organic solvents such as ethyl acetate and ketones, and these may be used alone or in combination. After applying a solution containing alkoxysilane or halogenated silane to the crystallized glass plate by the dipping method, a silica layer is formed through a drying or firing step.

  As the alkoxysilane, tetraalkoxysilane or trialkoxysilane is preferably condensed three-dimensionally to form a dense layer. The alkoxyl group of alkoxysilane is preferably a lower alkoxyl group such as methoxy, ethoxy, propoxy, butoxy and the like, and consists of at least one selected from them. In addition, you may use these alkoxysilanes individually or in mixture of 2 or more types as appropriate.

  The halogenated silane is preferable because tetrahalogenated silane or trihalogenated silane is three-dimensionally condensed to easily form a dense layer. The halogen group of the halogenated silane is chlorine, bromine or iodine, and consists of at least one selected from them. In addition, you may use these halogenated silanes individually or in mixture of 2 or more types as appropriate.

  The double oxide of silicon and zirconium is represented by the general formula (SiOm) x (ZrOn) y, and the mixture of oxides of silicon and zirconium is represented by the general formula (SiOm) x and (ZrOn) y (m and n are 1 to 1). Any number of 4 x + y = 1).

  In the layer composed of a double oxide of silicon and zirconium or the layer composed of a mixture of oxides of silicon and zirconium, the ratio of silicon oxide and zirconium oxide is not particularly limited. For example, the mass ratio is 1:90 to 1: 90, preferably 10:90 to 90:10, more preferably 20:80 to 80:20. In addition, in the case of a double oxide film of silicon and zirconium, it is preferable that the content when the silicon component is converted into silicon oxide satisfies the range.

  A layer made of a double oxide of silicon and zirconium or a layer made of a mixture of oxides of silicon and zirconium is immersed in a solution containing a silicon component and a zirconium component in a crystallized glass plate, as in the case of a silica layer. It is formed by applying and drying or baking.

  As a raw material of the silicon component, various water-soluble salts such as various alkali silicates, colloidal silica (silica sol), and various silicate alkoxides represented by ethyl silicate are preferable. When alkoxides are used, it is preferable to use a sol obtained by hydrolyzing these in the presence of water and a catalyst (acid or alkali) because a good film can be obtained.

  As a raw material for the zirconium component, it is preferable to use a water-soluble salt such as zirconium oxychloride or zirconium oxynitrate, an alkoxide such as zirconium tetrabutoxide or a hydrolyzate thereof, or a zirconia sol.

  In addition, the thickness of the silica containing inorganic coating layer formed can be adjusted by adjusting the density | concentration of a raw material solution suitably. For example, the thickness of the silica layer to be formed can be appropriately adjusted by changing the concentration of the solution containing alkoxysilane or halogenated silane. The concentration of the solution containing alkoxysilane or halogenated silane is preferably 1 to 10% by mass, and more preferably 2 to 6% by mass. If the concentration of the solution is less than 1% by mass, it tends to be difficult to form a silica layer having a desired thickness. On the other hand, when the concentration of the solution exceeds 10% by mass, the silica layer tends to be thicker than necessary, which is not preferable from the viewpoint of economy and resource saving.

  The method for forming the silica-containing inorganic coating layer is not limited to the dipping method, and other known methods such as coater, spray, and screen printing can also be used.

  The top plate for a cooker of the present invention is manufactured as follows. First, a transparent crystallized glass plate molded and processed to a predetermined size is prepared. Further, a resin and an organic solvent are appropriately added to the mixed powder of the inorganic pigment and the glass powder to form a paste. The obtained paste is printed on the surface of the crystallized glass plate by a method such as screen printing or transfer, dried, and then fired to form an inorganic pigment layer. Next, a silica-containing inorganic coating layer is formed on the transparent crystallized glass plate according to the method described above. Furthermore, the top plate for a cooking appliance of the present invention can be obtained by applying a heat-resistant resin onto the silica-containing inorganic coating layer by a method such as spraying or printing, if necessary, and drying.

  Hereinafter, although the top plate for cookers of this invention is demonstrated in detail based on an Example, this invention is not limited to these Examples.

Example 1
First, a transparent crystallized glass plate N-0 manufactured by Nippon Electric Glass Co., Ltd. having a long side dimension of 300 mm, a short side dimension of 150 mm, and a plate thickness of 4 mm (average linear thermal expansion coefficient at 30 to 750 ° C .: −4 × 10 ⁻⁷ on one side of the / ° C.), a commercially available Cu-Cr-Mn type black inorganic pigment powder and _B 2 _O 3 -SiO ₂ -based mixed powder of glass powder (in a weight ratio of 7: 3) as the cellulose and organic solvent frit consisting An inorganic pigment paste prepared by adding terbionelle was 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 an inorganic pigment layer having a thickness of 4 μm on the crystallized glass plate.

  Next, a tetraalkoxysilane solution was applied to the glass plate on which the inorganic pigment layer was formed by a dipping method, and baked at 600 to 700 ° C. to form a 0.05 μm thick silica layer.

  Furthermore, a commercially available polyimide resin is screen-printed on the silica layer on the side of the glass plate on which the inorganic pigment layer is formed, and baked at 300 ° C. for 20 minutes to form a heat-resistant resin layer having a thickness of 5 μm. A dexterous top plate was obtained.

  Commercially available silicon grease was applied on the heat-resistant resin layer of the obtained cooker top plate and held at 350 ° C. for 60 minutes in an electric furnace. Visually confirm the silicon grease stain from the surface of the glass plate, `` ◎ '' if the silicon grease stain was not observed, but the silicon grease stain was found to be at a usable level “○” and those with a clear silicone grease stain were evaluated as “x”. The results are shown in Table 1.

(Example 2)
A top plate for a cooker was produced in the same manner as in Example 1 except that the thickness of the silica layer was 1 μm. After applying commercially available silicon grease on the heat-resistant resin layer of the obtained top plate for cookers and holding it at 350 ° C. for 60 minutes in an electric furnace, the stain of the silicon grease is visually confirmed from the surface of the glass plate. did. The results are shown in Table 1.

(Example 3)
A top plate for a cooker was produced in the same manner as in Example 1 except that the thickness of the silica layer was 1.5 μm. After applying commercially available silicon grease on the heat-resistant resin layer of the obtained top plate for cookers and holding it at 350 ° C. for 60 minutes in an electric furnace, the stain of the silicon grease is visually confirmed from the surface of the glass plate. And evaluated according to the following criteria. The results are shown in Table 1.

Example 4
A top plate for a cooker was produced in the same manner as in Example 1 except that the thickness of the silica layer was 1.5 μm and a silicon resin was formed as a heat resistant resin layer instead of the polyimide resin. After applying commercially available silicon grease on the heat-resistant resin layer of the obtained top plate for cookers and holding it at 350 ° C. for 60 minutes in an electric furnace, the stain of the silicon grease is visually confirmed from the surface of the glass plate. did. The results are shown in Table 1.

(Example 5)
A cooker top plate was prepared in the same manner as in Example 1 except that the thickness of the silica layer was 0.03 μm. After applying commercially available silicon grease on the heat-resistant resin layer of the obtained top plate for cookers and holding it at 350 ° C. for 60 minutes in an electric furnace, the stain of the silicon grease is visually confirmed from the surface of the glass plate. did. The results are shown in Table 1.

(Comparative Example 1)
A cooker top plate was prepared in the same manner as in Example 1 except that the silica layer was not formed. After applying commercially available silicon grease on the heat-resistant resin layer of the obtained top plate for cookers and holding it at 350 ° C. for 60 minutes in an electric furnace, the stain of the silicon grease is visually confirmed from the surface of the glass plate. did. The results are shown in Table 1.

(Example 6)
A glass plate on which the inorganic pigment layer obtained in Example 1 was formed was screen-printed with a solution containing tetraethoxysilane and zirconium tetrabutoxide, and baked at 850 ° C. to form 0.05 μm thick silicon and zirconium. A layer made of a double oxide was formed. The ratio of silicon oxide and zirconium oxide in the formed layer was 1: 9 by mass ratio.

  Further, a polyimide resin is screen-printed on a layer made of a double oxide of silicon and zirconium, and baked at 300 ° C. for 20 minutes to form a heat-resistant resin layer having a thickness of 5 μm, thereby obtaining a top plate for a cooker. It was.

  Commercially available silicon grease was applied on the heat-resistant resin layer of the obtained cooker top plate and held at 350 ° C. for 60 minutes in an electric furnace. The stain of silicon grease was visually confirmed from the surface of the glass plate. The results are shown in Table 2.

(Example 7)
A cooker top plate was produced in the same manner as in Example 1 except that the heat-resistant resin layer was not formed. A commercially available silicon grease was applied on the silica layer of the top plate for the cooker obtained, and held at 350 ° C. for 60 minutes in an electric furnace, and then the stain of the silicon grease was visually confirmed from the surface of the glass plate. . The results are shown in Table 2.

  As is clear from Tables 1 and 2, the top plates for cooking utensils of Examples 1 to 4 and 6 did not show any silicon grease stain due to excessive heating. Although a silicon grease stain was observed, it was a usable level. On the other hand, the top plate for a cooker of Comparative Example 1 was not preferable in terms of appearance because the silica layer was clearly not observed from the cooking surface side because the silica layer was not provided.

  As described above, the top plate for a cooker of the present invention is suitable as a top plate for a cooker used for an infrared heating cooker, an electromagnetic heating cooker, and a gas cooker provided with a radiant heater or a halogen heater.

It is the schematic which shows one Embodiment of the top plate for cookers of this invention. It is the schematic which shows another embodiment of the top plate for cookers of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent crystallized glass board 2 Inorganic pigment layer 3 Heat resistant resin layer 4 Silica containing inorganic coating layer 5 Temperature sensor 6 Adhesive

Claims (4)

  A top plate for a cooking appliance, wherein an inorganic pigment layer is formed on the surface of a transparent crystallized glass plate, wherein a silica-containing inorganic coating layer is formed on the inorganic pigment layer.   The top plate for a cooking appliance according to claim 1, wherein a heat-resistant resin layer is formed on the silica-containing inorganic coating layer.   The cooking according to claim 1 or 2, wherein the silica-containing inorganic coating layer is a silica layer, a layer made of a double oxide of silicon and zirconium, or a layer made of a mixture of silicon oxide and zirconium oxide. Top plate for dexterity.   The top plate for a cooking appliance according to any one of claims 1 to 3, wherein the silica-containing inorganic coating layer has a thickness of 0.03 to 1.5 µm.