JP6701541B2 - Low expansion substrate with glass powder, composite powder and painting layer - Google Patents

Description

  The present invention relates to a glass powder, a composite powder, and a low-expansion substrate with a paint layer, and more particularly to a glass powder, a composite powder, and a low-expansion substrate with a paint layer suitable for a cooker top plate having a paint layer.

  The low-expansion crystallized glass substrate is widely used as a top plate for a cooker because it has high heating durability and high thermal shock resistance.

Further, the surface of the cooker top plate may be decorated with a painting layer in order to enhance the aesthetic appearance. The painting layer is generally a sintered body of a composite powder containing glass powder, inorganic pigment powder and the like. For example, Patent Document 1, by _{mass%, SiO 2 55~70%, B} 2 O 3 15~25%, Al 2 O 3 3~10%, BaO 0.1~4.9%, ZnO 0. _{1~5%, CaO 0~3%, 0~3} % MgO, Li 2 O 0.1~5%, Na 2 O 0~10%, K 2 O 0.3~15%, F 2 0~2 %, and the softening point is 600° C. or higher and lower than 700° C., and a lead-free glass powder for forming a painted layer is disclosed.

  The method for forming the painting layer on the surface of the crystallized glass substrate is as follows. First, glass powder and inorganic pigment powder are mixed to obtain a composite powder. Next, the obtained composite powder is dispersed in a vehicle containing an organic binder, a solvent and the like to form a paste. Subsequently, the obtained composite powder paste is transferred onto a crystallized glass substrate by a screen printing method or the like, dried, and then fired under appropriate firing conditions. When the composite powder is fired, the composite powder (glass powder) is softened and fluidized and then sintered. As a result, the composite powder is strongly fixed on the crystallized glass substrate to form a painting layer.

JP, 2007-39294, A

  By the way, the glass powder described in Patent Document 1 softens and flows at a low temperature, but has a high coefficient of thermal expansion, and thus it is difficult to reduce the coefficient of thermal expansion of the painting layer. When the thermal expansion coefficient of the painting layer is high, cracks are likely to occur in the crystallized glass substrate with the painting layer. This tendency becomes easier to manifest as the coefficient of thermal expansion of the crystallized glass substrate is lower. The cracks not only deteriorate the properties such as water resistance and acid resistance, but also cause a problem that stains are accumulated inside the cracks and spoil the appearance.

  Furthermore, if the thermal expansion coefficient of the painting layer is high, excessive tensile stress is applied to the painting layer, and the mechanical strength of the painting layer is likely to deteriorate due to external force.

  In addition, the cooker top plate is exposed to boiling water, fruit juice, and seasonings during use. Therefore, the painted layer may be required to have high water resistance and acid resistance. Specifically, when the painting layer is placed on the cooking surface side of the cooker top plate, even if the painting layer is placed on the opposite side of the cooking surface, a hole is opened to allow gas appliances to pass through. When processed, high water resistance and acid resistance are required. Along with this, glass powders are also required to have high water resistance and acid resistance.

  The present invention has been made in view of the above circumstances, and its technical problem is to create a glass powder and a composite powder having a low coefficient of thermal expansion, softening and flowing at low temperature, and further having high water resistance and acid resistance. Is.

As a result of various studies, the present inventor introduced a predetermined amount of Li ₂ O into the SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ -based glass powder and increased the content of SiO ₂ , The present invention proposes to solve the above technical problems by reducing the content of B ₂ O ₃ , and proposes the present invention. That is, the glass powder of the present invention, as a glass composition, is mol% in terms of SiO ₂ 48 to 75%, B ₂ O _{3 5 to} 23%, Al ₂ O ₃ 5 to 25%, Li ₂ O 5 to 30%, ZnO is contained in an amount of 0 to 25%, and the molar ratio SiO ₂ /B ₂ O ₃ is 3.23 or more. Here, “SiO ₂ /B ₂ O ₃ ”is a value obtained by dividing the content of SiO _{2 by} the content of B ₂ O ₃ .

Glass powder of the present invention, the SiO ₂ in the glass composition 48-75 _mole%, B 2 _{O 3} of 5 to 23 mol%, the _Al 2 _{O 3} 5 to 25 mol%, 5 to 30 mol of Li ₂ O % Included. Thereby, the β-quartz solid solution having a low expansion can be deposited after being softened and fluidized favorably during firing. As a result, it becomes possible to achieve both softening fluidity and a low expansion coefficient.

On the other hand, when the content of SiO ₂ in the glass composition is decreased and the content of B ₂ O ₃ is increased, the softening fluidity of the glass powder is improved, but after the β-quartz solid solution is precipitated, the glass matrix Water resistance and acid resistance are likely to decrease. Therefore, the glass powder of the present invention regulates the molar ratio SiO ₂ /B ₂ O ₃ in the glass composition to 3.23 or more. Thereby, the water resistance and the acid resistance of the glass matrix after crystal precipitation are improved, so that the water resistance and the acid resistance of the painting layer can be appropriately increased.

Secondly, in the glass powder of the present invention, the content of B ₂ O ₃ in the glass composition is preferably 16 mol% or less.

  Thirdly, in the glass powder of the present invention, the content of ZnO in the glass composition is preferably 0.1 to 7.6 mol %. This makes it possible to increase the precipitation amount of the β-quartz solid solution while suppressing the precipitation of different crystals during firing. As a result, it becomes possible to reduce the firing temperature dependence of the thermal expansion coefficient, and it is easy to prevent the situation where a locally distorted stress remains after firing or a location where the thermal expansion coefficient locally differs. Become. Further, it becomes easy to prevent a situation in which the coefficient of thermal expansion of the painting layer differs between manufacturing lots.

Fourth, the glass powder of the present invention preferably further contains TiO ₂ and ZrO ₂ in a total amount of 0.1 to 15 mol% in the glass composition.

Fifth, it is preferable that the glass powder of the present invention does not substantially contain PbO and Bi ₂ O ₃ in the glass composition. Here, “substantially does not include” means that the explicit component is mixed at an impurity level, and specifically, the content of the explicit component is less than 0.1% by mass. Refers to the case.

Sixth, the glass powder of the present invention preferably has a coefficient of thermal expansion of 25×10 ⁻⁷ /° C. or less after firing at 700° C. for 10 minutes. Here, the “thermal expansion coefficient” is a value measured in a temperature range of 30 to 350° C. using a TMA device. As a measurement sample, a powder compact of glass powder, which was densely sintered under a firing condition of 700° C. for 10 minutes and then processed into a predetermined shape, was used.

  Seventh, when the glass powder of the present invention is fired at 700° C. for 10 minutes, it is preferable that β-quartz solid solution is precipitated as a main crystal. Here, the "main crystal" refers to a crystal having the highest peak intensity when measured by the X-ray diffraction method.

  Eighth, it is preferable that the glass powder of the present invention has a softening point of 550 to 700° C. measured by a macro type DTA device. Here, the softening point measured by the macro type DTA device indicates the temperature (Ts) of the fourth bending point shown in FIG. The measurement by the macro type DTA device is performed in air, and the temperature rising rate is 10° C./min.

  Ninth, the composite powder of the present invention is a composite powder containing 55 to 100 mass% of glass powder, 0 to 45 mass% of inorganic pigment powder, and 0 to 40 mass% of refractory filler powder, and the glass powder is It is preferably the above glass powder.

  Tenth, in the composite powder of the present invention, the inorganic pigment powder is preferably a Cr-Cu-based composite oxide. Here, the term "-based complex oxide" refers to a complex oxide containing an explicit component as an essential component.

Eleventh, the low-expansion substrate with a painting layer of the present invention is a low-expansion substrate with a painting layer having a painting layer on the surface of the low-expansion substrate, wherein the painting layer is a sintered body of a composite powder, and The powder is preferably the above composite powder. Here, the “low expansion substrate” refers to a substrate having a thermal expansion coefficient of 35×10 ⁻⁷ /° C. or less in the temperature range of 30 to 350° C.

  Twelfth, in the low expansion substrate with a paint layer of the present invention, it is preferable that β-quartz solid solution is precipitated in the paint layer.

  Thirteenth, it is preferable that the low-expansion substrate with a painted layer of the present invention is a low-expansion substrate which is a transparent crystallized glass substrate, and β-quartz solid solution is deposited as a main crystal.

  Fourteenth, it is preferable that the low expansion substrate with a painting layer of the present invention is a quartz substrate.

  Fifteenth, it is preferable that the low expansion substrate with a paint layer of the present invention is used for a top plate for a cooker.

It is a chart which shows the softening point and the crystallization temperature measured by the macro type DTA apparatus.

The glass powder of the present invention has a glass composition of, in mol %, SiO ₂ 48 to 75%, B ₂ O _{3 5 to} 23%, Al ₂ O ₃ 5 to 25%, Li ₂ O 5 to 30%, and ZnO 0. ˜25%, and the molar ratio SiO ₂ /B ₂ O ₃ is 3.23 or more. The reason why the content range of each component is limited as described above is shown below. In the description of the content range of each component,% indication means mol%.

SiO ₂ is a component that forms a glass skeleton, is a crystal constituent component of the β-quartz solid solution, and is a component that enhances water resistance and acid resistance of the glass matrix after crystal precipitation. The content of SiO ₂ is 48 to 75%, preferably 50 to 68%, 52 to 66%, 54 to 64%, and particularly 56 to 62%. If the content of SiO ₂ is too small, the thermal stability will be unduly low, and crystals will be likely to precipitate before the glass powder is sufficiently sintered. Further, it becomes difficult for the β-quartz solid solution to precipitate during firing, and as a result, it becomes difficult to reduce the thermal expansion coefficient of the painting layer. Furthermore, the water resistance and acid resistance of the glass matrix after crystal precipitation are likely to decrease. On the other hand, if the content of SiO ₂ is too large, the softening point rises, and the softening fluidity of the glass powder tends to decrease.

B ₂ O ₃ is a component that forms a glass skeleton and is a component that lowers the softening point without increasing the thermal expansion coefficient. The content of B ₂ O ₃ is 5 to 23%, preferably 7 to 19%, 9 to 16%, 10 to 14%, and particularly 10 to 12%. If the content of B ₂ O ₃ is too small, the thermal stability becomes unduly low, and crystals tend to precipitate before the glass powder is sufficiently sintered. Furthermore, the softening point rises, and the softening fluidity of the glass powder tends to decrease. On the other hand, when the content of B ₂ O ₃ is too large, the water resistance and acid resistance of the glass matrix after crystal precipitation are likely to decrease.

Molar ratio _SiO 2 _/ B 2 _{O 3} is at 3.23 or more, preferably 3.5 or more, 3.9 or more 4.2～10,4.5～8,4.8～7, especially 5-6 Is. If the molar ratio SiO ₂ /B ₂ O ₃ is too small, the water resistance and acid resistance of the glass matrix after crystal precipitation are likely to decrease, and the water resistance and acid resistance of the painting layer are likely to decrease. On the other hand, if the molar ratio SiO ₂ /B ₂ O ₃ is too large, heterogeneous crystals such as β-spodumene are deposited, and the amount of β-quartz solid solution deposited is likely to decrease.

Al ₂ O ₃ is a crystal constituent component of the β-quartz solid solution and a component that enhances acid resistance. The content of Al ₂ O ₃ is 5 to 25%, preferably 6 to 20%, 7 to 16%, 8 to 13%, and particularly 9 to 11%. When the content of Al ₂ O ₃ is too small, the β-quartz solid solution is less likely to be deposited during firing, and as a result, the thermal expansion coefficient of the painting layer is less likely to be lowered. If the content of Al ₂ O ₃ is too large, the softening point rises, and the softening fluidity of the glass powder tends to decrease.

Li ₂ O is a crystal constituent component of the β-quartz solid solution and is a component that lowers the softening point without increasing the thermal expansion coefficient. The content of Li ₂ O is 5 to 30%, preferably 7 to 25%, 10 to 22%, 12 to 20%, 13 to 18%, and particularly 14 to 16%. If the content of Li ₂ O is too small, the softening point rises, and the softening fluidity of the glass powder tends to decrease. Furthermore, the β-quartz solid solution is less likely to precipitate during firing, and as a result, the thermal expansion coefficient of the painting layer is less likely to decrease. On the other hand, if the content of Li ₂ O is too large, the acid resistance tends to decrease.

  ZnO is a component that lowers the softening point without significantly increasing the thermal expansion coefficient. It is also a component that promotes crystallization. The content of ZnO is 0 to 25%, preferably 0 to 20%, 0 to 16%, 1 to 14%, 2 to 12%, 3 to 10%, and particularly 4 to 7.6%. When it is desired to increase the precipitation amount of the β-quartz solid solution while suppressing the precipitation of heterogeneous crystals, the ZnO content is 0.1 to 7.6%, 1 to 5%, and particularly 1.5 to 3%. Is. When the content of ZnO is too large, the water resistance and acid resistance of the glass matrix after crystal precipitation are likely to be lowered, and further, a different crystal of Li-Si-Zn system is likely to be precipitated, and the amount of β-quartz solid solution is precipitated. Is likely to decrease.

  In addition to the above components, for example, the following components may be introduced.

Na ₂ O and K ₂ O are components that lower the softening point, but if the content is too large, the β-quartz solid solution is less likely to precipitate during firing, and as a result, the thermal expansion coefficient of the painting layer is reduced. It gets harder. Furthermore, the acid resistance tends to decrease. Therefore, the total amount of Na ₂ O and K ₂ O is preferably 0 to less than 8%, 0 to 6%, 0 to 4%, 0 to 2%, and particularly 0 to less than 1%. The content of Na ₂ O is preferably 0 to less than 8%, 0 to 6%, 0 to 4%, 0 to 2%, and particularly 0 to less than 1%. The content of K ₂ O is preferably 0 to less than 8%, 0 to 6%, 0 to 4%, 0 to 2%, and particularly 0 to less than 1%. The molar ratio Li ₂ O/(Li ₂ O+Na ₂ O+K ₂ O) is preferably 0.5 or more, 0.6 or more, 0.7 or more, 0.8 or more, and particularly 0.9 or more. Note that “Li ₂ O/(Li ₂ O+Na ₂ O+K ₂ O)” is a value obtained by dividing the content of Li ₂ O by the total amount of Li ₂ O, Na ₂ O, and K ₂ O.

TiO ₂ and ZrO ₂ are components that enhance the crystallinity, and also enhance the water resistance and acid resistance of the glass matrix after crystal precipitation, but if the content is too large, the softening point increases, The softening fluidity of the glass powder is likely to decrease. Furthermore, the thermal stability becomes unduly low, and crystals tend to precipitate before the glass powder is sufficiently sintered. The total amount of TiO ₂ and ZrO ₂ is preferably 0 to 15%, 0 to 12%, 0.1 to 10%, 1 to 8%, and particularly 2 to 6%. The content of TiO ₂ is preferably 0 to 15%, 0 to 12%, 0.1 to 10%, 1 to 8%, and particularly 2 to 6%. The content of ZrO ₂ is preferably 0 to 10%, 0 to 5%, 0 to less than 3%, 0 to 2%, and particularly 0 to 1%.

  MgO is a component that enhances thermal stability. The content of MgO is preferably 0 to 7%, 0 to 5%, 0 to 3%, and particularly 0 to 1%. If the content of MgO is too large, the softening point rises, and the softening fluidity of the glass powder tends to decrease.

  BaO is a component that enhances thermal stability. The content of BaO is preferably 0 to 7%, 0 to 5%, and particularly 0.1 to 3%. When the content of BaO is too large, the coefficient of thermal expansion rises unduly, and it becomes difficult to reduce the coefficient of thermal expansion of the painting layer.

  CuO is a component for coloring the glass black. The content of CuO is preferably 0 to 7%, 0 to 5%, 0 to 3%, and particularly 0 to 1%. If the content of CuO is too large, the thermal stability becomes unduly low, and crystals tend to precipitate before the glass powder is sufficiently sintered.

In addition to the above components, other components can be introduced, if desired, for example up to 15%, 10%, 5%, especially 1%. _{Specifically, CaO, SrO, Cr 2 O} 3, MnO, SnO 2, CeO 2, P 2 O 5, La 2 O 3, Nd 2 O 3, Co 2 O 3, F, the total amount of Cl and the like or It can be introduced individually, for example up to 15%, 10%, 5%, in particular up to 1%.

From an environmental point of view, it is preferable that PbO is not substantially contained, and that Bi ₂ O ₃ is not substantially contained.

The average particle diameter D ₅₀ of the glass powder is 15 μm or less, preferably 0.5 to 10 μm, and particularly preferably 0.7 to ₅ μm. If the particle size of the glass powder is too large, the screen printability tends to deteriorate, and the color tone of the painting layer tends to become uneven. Here, the “average particle diameter D _{50 ”} refers to a value measured by a laser diffractometer, and in the volume-based cumulative particle size distribution curve when measured by a laser diffraction method, the cumulative amount is from the smaller particles. The cumulative particle size is 50% (hereinafter the same).

  The softening point of the glass powder measured by a macro type DTA apparatus is preferably 550 to 700°C, 570 to 695°C, 590 to 690°C, and particularly 620 to 685°C. The lower the softening point, the more it is possible to lower the firing temperature, the color developability of the inorganic pigment powder is improved, but if the softening point is too low, other properties, especially water resistance of the glass matrix after crystal precipitation, Acid resistance is likely to decrease. On the other hand, if the softening point is too high, the firing temperature may be unduly increased, which may increase the firing cost.

  The crystallization temperature of the glass powder measured by a macro type DTA device is preferably 650 to 750°C, 660 to 740°C, and particularly 670 to 730°C. If the crystallization temperature is too low, crystals will precipitate before the glass powder is sufficiently sintered during firing, and the denseness of the painting layer tends to be reduced. On the other hand, if the crystallization temperature is too high, it becomes difficult for crystals to precipitate in the painting layer during firing, and it becomes difficult to reduce the thermal expansion coefficient of the painting layer. Here, the crystallization temperature measured by the macro type DTA device refers to the exothermic peak temperature (Tc) due to the crystal precipitation shown in FIG.

The coefficient of thermal expansion of the sintered body after firing the glass powder under the firing conditions of 700° C. for 10 minutes is preferably 25×10 ⁻⁷ /° C. or less, 15×10 ⁻⁷ /° C. or less, 10×10 ⁻⁷ / C. or less, especially −10×10 ^{−7 to} 5×10 ⁻⁷ /° C. If the coefficient of thermal expansion of the sintered body of glass powder is too high, it becomes difficult to lower the coefficient of thermal expansion of the painting layer, and cracks easily occur in the low expansion substrate with the painting layer. In addition, the painting layer is likely to come off.

  When the glass powder is fired under the condition of 700° C. for 10 minutes, β-quartz solid solution as a main crystal is preferably precipitated. By doing so, the coefficient of thermal expansion of the painting layer is significantly reduced, so that it is possible to accurately prevent the occurrence of cracks in the low expansion substrate with the painting layer.

  The composite powder of the present invention contains at least glass powder and inorganic pigment powder, and if necessary, refractory filler powder and the like. The glass powder is a component for dispersing the inorganic pigment powder and fixing it to the low expansion substrate. The inorganic pigment powder is a component that is colored black or the like to enhance the decorative property. The refractory filler powder is an optional component, a component for increasing the mechanical strength, and a component for adjusting the thermal expansion coefficient. In addition to the above, metal powder such as Cu powder may be added in order to enhance the color developability.

  The composite powder of the present invention preferably contains 55 to 100 mass% of glass powder, 0 to 45 mass% of inorganic pigment powder, and 0 to 40 mass% of refractory filler powder.

  The content of the glass powder is preferably 55 to 100% by mass, 55 to 95% by mass, 55 to 90% by mass, 55 to 85% by mass, 60 to 80% by mass, and particularly 65 to 75% by mass. If the content of the glass powder is too low, the adhesiveness between the painting layer and the low expansion substrate tends to deteriorate. In addition, when the content of the glass powder is too large, the amount of the inorganic pigment powder becomes relatively small, and the decorative property of the painting layer is likely to deteriorate.

  The content of the inorganic pigment powder is preferably 0 to 45% by mass, 5 to 45% by mass, 10 to 45% by mass, 13 to 45% by mass, and particularly 15 to 30% by mass. If the content of the inorganic pigment powder is too small, the decorative property tends to deteriorate. On the other hand, when the content of the inorganic pigment powder is too large, the amount of the glass powder becomes relatively small, and the adhesiveness between the painting layer and the low expansion substrate tends to decrease. Further, if the content of the inorganic pigment powder is too large, the surface smoothness of the painting layer is lowered, and the water resistance and acid resistance of the painting layer are likely to be lowered.

Various materials can be used for the inorganic pigment powder, for example, NiO (green), MnO ₂ (black), CoO (black), Fe ₂ O ₃ (brown brown), Cr ₂ O ₃ (green), TiO ₂ ( Colored oxides such as white), Cr-Al spinel (pink), Sn-Sb-V rutile (gray), Ti-Sb-Ni rutile (yellow), Zr-V baderite (yellow), etc. Oxide, Co-Zn-Al spinel (blue), Zn-Fe-Cr spinel (brown), Cr-Cu-Mn spinel, and other complex oxides, Ca-Cr-Si garnet (Victorian green color) ), Ca-Sn-Si-Cr-based sphene (pink), Zr-Si-Fe-based zircon (salmon pink), Co-Zn-Si-based willemite (dark blue), Co-Si-based olivine (dark blue) ) And the like, which can be mixed in the above proportions so as to obtain the desired color. In addition to the above-mentioned inorganic pigment powder, for example, in order to improve the hiding property and abrasion resistance of the painting layer, ZrSiO ₄ , talc, etc. may be mixed in appropriate amounts.

The average particle diameter D ₅₀ of the inorganic pigment powder is 9 μm or less, and preferably 0.5 to 4 μm. The maximum particle diameter D _max of the inorganic pigment powder is preferably 10 μm or less, and particularly preferably 2 to 8 μm. If the particle size of the inorganic pigment powder is too large, the screen printability tends to deteriorate, and the coloring property of the painting layer tends to deteriorate.

  The content of the refractory filler powder is preferably 0 to 40% by mass, 0 to 20% by mass, 0 to 15% by mass, 0 to 10% by mass, 0 to 5% by mass, 0 to 1% by mass, and particularly 0 to It is less than 0.1% by mass. If the content of the refractory filler powder is too large, the adhesiveness between the painting layer and the low expansion substrate tends to decrease.

  As the refractory filler powder, cordierite, willemite, alumina, zirconium phosphate, zircon, zirconia, tin oxide, mullite, silica, β-eucryptite, β-spodumene, β-quartz solid solution, zirconium phosphate tungstate, etc. Can be used.

  The composite powder of the present invention is mixed with a vehicle and used as a composite powder paste. The vehicle is mainly composed of a solvent and a resin. The solvent is added for the purpose of uniformly dispersing the composite powder while dissolving the resin. The resin is added for the purpose of adjusting the viscosity of the paste. Moreover, a surfactant, a thickener, etc. can be added if necessary.

  As the resin, acrylic acid ester (acrylic resin), ethyl cellulose, polyethylene glycol derivative, nitrocellulose, polymethylstyrene, polyethylene carbonate, methacrylic acid ester and the like can be used. In particular, acrylic acid ester and ethyl cellulose are preferable because they have good thermal decomposability.

  As a solvent, pine oil, N,N'-dimethylformamide (DMF), α-terpineol, higher alcohol, γ-butyl lactone (γ-BL), tetralin, butyl carbitol acetate, ethyl acetate, isoamyl acetate, diethylene glycol monoethyl. Ether, diethylene glycol monoethyl ether acetate, benzyl alcohol, toluene, 3-methoxy-3-methylbutanol, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether , Tripropylene glycol monobutyl ether, propylene carbonate, N-methyl-2-pyrrolidone and the like can be used. In particular, α-terpineol is preferable because it has high viscosity and good solubility of resin and the like.

  The composite powder paste is prepared, for example, by mixing the composite powder and the vehicle and then kneading the mixture uniformly with a three-roll mill.

  The composite material paste is applied to a low expansion substrate by using a coating machine such as a screen printing machine, and then subjected to a drying step and a firing step. Thereby, the painting layer can be formed on the surface of the low expansion substrate. The conditions for the drying step are generally at 70 to 150° C. for 10 to 60 minutes. The firing step is a step of decomposing and volatilizing the resin and sintering the composite powder to fix the painting layer on the surface of the low expansion substrate. The conditions for the firing step are generally at 650 to 850° C. for 5 to 30 minutes. As the firing temperature is lower in the firing step, the production efficiency is improved and the color developability of the inorganic pigment powder is improved, but on the other hand, the adhesion between the painting layer and the low expansion substrate is lowered.

  The low-expansion substrate with a painting layer of the present invention is a low-expansion substrate with a painting layer having a painting layer on the surface of the low-expansion substrate, wherein the painting layer is a sintered body of composite powder, and the composite powder is the above-mentioned composite. It is preferably a powder. The low-expansion substrate with a painted layer of the present invention includes the technical features of the composite powder of the present invention, but since its content has already been described, its explanation is omitted for convenience.

  In the low expansion substrate with a paint layer of the present invention, it is preferable that β-quartz solid solution is deposited on the paint layer. By doing so, the coefficient of thermal expansion of the painting layer is significantly reduced, so that it is possible to accurately prevent the occurrence of cracks in the low expansion substrate with the painting layer.

  In the low expansion substrate with a painted layer of the present invention, the low expansion substrate is preferably a crystallized glass substrate (particularly a transparent crystallized glass substrate), and it is also preferable that β-quartz solid solution is precipitated as a main crystal. With this, heating durability and thermal shock resistance can be improved.

The coefficient of thermal expansion of the crystallized glass substrate is preferably −10×10 ⁻⁷ to 30×10 ⁻⁷ /° C., and particularly preferably −5×10 ⁻⁷ to 10×10 ⁻⁷ /° C. When the coefficient of thermal expansion of the crystallized glass substrate is lowered, the heating durability and thermal shock resistance of the crystallized glass substrate are improved. As a result, it is suitable for a cooker top plate to which thermal shock due to rapid heating and rapid cooling is applied during use. Note that the cooker includes an electromagnetic cooker, an electric cooker, a gas cooker, and the like.

  In the low expansion substrate with a paint layer of the present invention, the thickness of the paint layer is preferably 1 to 30 μm, and particularly preferably 2 to 10 μm. If the thickness of the painting layer is too small, the pattern of the painting may become unclear. On the other hand, if the thickness of the painting layer is too thick, cracks may occur in the painting pattern.

  Hereinafter, the present invention will be described based on examples. The following embodiments are merely examples. The present invention is not limited to the following examples.

  Table 1 has shown the Example (sample No. 1-9) and comparative example (sample No. 10, 11) of this invention.

First, raw materials were blended so as to have the glass composition shown in the table and uniformly mixed to obtain a glass batch, which was then put into a platinum crucible and melted at 1400° C. for 3 hours. Then, the molten glass was formed into a film. Then, the obtained glass film was crushed by a ball mill and then air-classified to obtain a glass powder having an average particle diameter D ₅₀ of 2.5 μm.

  The softening point and crystallization temperature of each glass powder were measured using a macro type DTA device. Here, the measurement was performed in air, and the temperature rising rate was 10° C./min. The softening point refers to the temperature at the fourth inflection point, and the crystallization temperature refers to the exothermic peak temperature due to crystal precipitation.

  The main crystal has a peak intensity when measured by X-ray diffractometry, which is obtained by densely sintering a green compact of glass powder under a firing condition of 700° C. for 10 minutes and then processing it into a predetermined shape. The largest crystal.

  The thermal expansion coefficient of the glass powder is a value measured in a temperature range of 30 to 350° C. using a TMA device. Here, as a measurement sample, a powder compact of glass powder was densely sintered under a firing condition of 700° C. for 10 minutes and then processed into a predetermined shape.

The water resistance of the glass powder was evaluated as follows. That is, after compacting a green compact of a glass powder under a firing condition of 700° C. for 10 minutes, it was processed into a predetermined shape and used as a measurement sample, and when it was immersed in water at 90° C. for 2 hours, a change in appearance was observed. Those that were not recognized were evaluated as “◯”, and those that were observed in appearance change were evaluated as “x”.

Next, the glass powder and the inorganic pigment powder were mixed in the proportions shown in the table (total 100%) to obtain a composite powder. Here, as the inorganic pigment powder, a Cr—Cu—Mn-based composite oxide (average particle diameter D ₅₀ is 1.5 μm, maximum particle diameter D _max is 4.0 μm) is used.

  Further, the obtained composite powder and the vehicle were mixed and then uniformly kneaded with a three-roll mill to obtain a composite powder paste. A vehicle prepared by dissolving ethyl cellulose in α-terpineol was used as the vehicle, and the composite powder/vehicle was adjusted to 2-3 by mass ratio.

  Subsequently, the composite powder paste was screen-printed on one side of a 10 cm square transparent crystallized glass substrate (N-0 manufactured by Nippon Electric Glass Co., Ltd., main crystal: β-quartz solid solution), and then dried at 120° C. for 20 minutes. The above was placed in an electric furnace at 700° C., baked for 10 minutes, and naturally cooled to room temperature to obtain a transparent crystallized glass substrate with a paint layer having a thickness of 10 μm.

  The presence or absence of cracks was evaluated by observing the transparent crystallized glass substrate with the paint layer, and those in which no cracks were observed were evaluated as “◯”, and those in which cracks were observed were evaluated as “x”.

  Abrasion resistance is "○" when the painting layer was not peeled off after reciprocating 100 times with a load of 1.3 kg and a speed of 100 mm/sec for one way using sandpaper of #1000, and the painting layer What peeled off was evaluated as "x".

  The water resistance of the paint layer was "○" when no change was observed in the paint layer when it was immersed in water at 90°C for 24 hours, and "△" when the appearance change was slightly observed. What was clearly recognized was evaluated as "x".

  The acid resistance of the paint layer is "○" when no change in appearance was observed in the paint layer when immersed in a 0.1% by mass HCl aqueous solution at 40°C for 1 hour, and when the appearance change was slightly observed. The evaluation was evaluated as “x” when “Δ” and the change in appearance was clearly recognized.

As is clear from Table 1, the sample No. Nos. 1 to 9 had a low coefficient of thermal expansion, and the evaluation of water resistance and acid resistance was good. On the other hand, sample No. In No. 10, since the molar ratio SiO ₂ /B ₂ O ₃ was small, the evaluation of water resistance and acid resistance was poor. In addition, the sample No. In No. 11, crystals did not precipitate after firing, and cracks occurred in the case of a transparent crystallized glass substrate with a painting layer.

  Table 2 has shown the Example (sample No. 12-16) of this invention.

First, raw materials were blended so as to have the glass composition shown in the table and uniformly mixed to obtain a glass batch. The glass batch was put into a platinum crucible and melted at 1400° C. for 3 hours. Then, the molten glass was formed into a film. Then, the obtained glass film was crushed by a ball mill and then air-classified to obtain a glass powder having an average particle diameter D ₅₀ of 2.5 μm.

  The softening point and crystallization temperature of each glass powder were measured using a macro type DTA device. Here, the measurement was performed in air, and the temperature rising rate was 10° C./min. The softening point refers to the temperature at the fourth inflection point, and the crystallization temperature refers to the exothermic peak temperature due to crystal precipitation.

  The main crystal has a peak intensity when measured by X-ray diffractometry, which is obtained by densely sintering a green compact of glass powder under a firing condition of 700° C. for 10 minutes and then processing it into a predetermined shape. The largest crystal. Sample No. Sample No. No. 16 had the largest amount of β-quartz solid solution deposited, and the smallest amount of heterogeneous crystals (β-spodumene) deposited.

  The thermal expansion coefficient of the glass powder is a value measured in a temperature range of 30 to 350° C. using a TMA device. Here, as a measurement sample, a powder compact of glass powder was densely sintered under the firing conditions shown in the table and then processed into a predetermined shape.

  The water resistance of the glass powder was evaluated as follows. That is, after compacting a green compact of a glass powder under a firing condition of 700° C. for 10 minutes, it was processed into a predetermined shape and used as a measurement sample, and when it was immersed in water at 90° C. for 2 hours, a change in appearance was observed. Those that were not recognized were evaluated as “◯”, and those that were observed in appearance change were evaluated as “x”.

Next, the glass powder and the inorganic pigment powder were mixed in the proportions shown in the table (total 100%) to obtain a composite powder. Here, as the inorganic pigment powder, a Cr—Cu—Mn-based composite oxide (average particle diameter D ₅₀ is 1.5 μm, maximum particle diameter D _max is 4.0 μm) is used.

  Further, the obtained composite powder and the vehicle were mixed and then uniformly kneaded with a three-roll mill to obtain a composite powder paste. A vehicle prepared by dissolving ethyl cellulose in α-terpineol was used as a vehicle, and the composite powder/vehicle was adjusted to 2-3 by mass ratio.

  Subsequently, the composite powder paste was screen-printed on one side of a 10 cm square transparent crystallized glass substrate (N-0 manufactured by Nippon Electric Glass Co., Ltd., main crystal: β-quartz solid solution), and then dried at 120° C. for 20 minutes. The above was placed in an electric furnace at 700° C., baked for 10 minutes, and naturally cooled to room temperature to obtain a transparent crystallized glass substrate with a paint layer having a thickness of 10 μm.

  The presence or absence of cracks was evaluated by observing the transparent crystallized glass substrate with the paint layer, and those in which no cracks were observed were evaluated as “◯”, and those in which cracks were observed were evaluated as “x”.

  Abrasion resistance is "○" when the paint layer was not peeled after 100 times of reciprocating the paint layer with a load of 1.3 kg and a speed of 100 mm/sec one way using #1000 sandpaper. What peeled off was evaluated as "x".

  The water resistance of the paint layer was "○" when no change was observed in the paint layer when it was immersed in water at 90°C for 24 hours, and "△" when the appearance change was slightly observed. What was clearly recognized was evaluated as "x".

  Regarding the acid resistance of the paint layer, when the paint layer was not immersed in 0.1% by mass HCl aqueous solution at 40° C. for 1 hour, the appearance change was not observed. The evaluation was evaluated as “x” when “Δ” and the change in appearance was clearly recognized.

  As is clear from Table 2, the sample No. Nos. 12 to 16 had a low coefficient of thermal expansion, and were evaluated for water resistance and acid resistance. In particular, the sample No. Since Nos. 12, 14 and 16 contained a small amount of ZnO in the glass composition, the fluctuation range of the thermal expansion coefficient was small even if the firing temperature was changed. That is, the dependence of the coefficient of thermal expansion on the firing temperature was small.

The present invention, glass powder, low expansion substrate with the composite powder and the decorative layer is suitable to top plate for a cooking appliance or the like having a decorative layer, a quartz substrate, Si ₃ N ₄ coating of low expansion substrate such as a substrate, sealing It is also applicable to uses such as clothes. When the composite powder of the present invention is applied to applications such as sealing and coating, it is not necessary to introduce an inorganic pigment powder, and instead, a refractory filler powder is added in an amount of 0. You may introduce 1 mass% or more.

Claims (14)

As a glass composition, in _{mol%, SiO 2 48~75%, B} 2 O 3 5~23%, Al 2 O 3 5~25%, Li 2 O 10~30%, 0~25% ZnO, Na 2 O 0 to 4%, TiO ₂ 0.1 to 12%, the molar ratio SiO ₂ /B ₂ O ₃ is 4.2 or more, and β-quartz as a main crystal when fired at 700° C. for 10 minutes. A glass powder characterized in that a solid solution is deposited. Glass powder according to claim 1, wherein the content of B ₂ O ₃ in the glass composition is less than 16 mol%.   Content of ZnO in a glass composition is 0.1-7.6 mol%, The glass powder of Claim 1 or 2 characterized by the above-mentioned. The glass powder according to any one of claims 1 to 3, further comprising TiO ₂ and ZrO ₂ in a total amount of 0.1 to 15 mol% in the glass composition. Glass powder according to claim 1, wherein the substantially contains no PbO and Bi ₂ O ₃ in the glass composition. The glass powder according to claim 1, which has a thermal expansion coefficient of 25×10 ⁻⁷ /° C. or less after firing under the condition of 700° C. for 10 minutes.   The softening point measured by a macro type DTA device is 550 to 700°C, and the glass powder according to any one of claims 1 to 6. A composite powder containing 55 to 100% by mass of glass powder, 0 to 45% by mass of inorganic pigment powder, and 0 to 40% by mass of refractory filler powder,
A composite powder, wherein the glass powder is the glass powder according to any one of claims 1 to 7.   The composite powder according to claim 8, wherein the inorganic pigment powder is a Cr-Cu-based composite oxide. A low expansion substrate with a painting layer having a painting layer on the surface of the low expansion substrate,
A low expansion substrate with a paint layer, wherein the paint layer is a sintered body of the composite powder, and the composite powder is the composite powder according to claim 8 or 9.   The low expansion substrate with a paint layer according to claim 10, wherein the β-quartz solid solution is deposited on the paint layer.   The low expansion substrate with a paint layer according to claim 10 or 11, wherein the low expansion substrate is a transparent crystallized glass substrate, and β-quartz solid solution is deposited as a main crystal. The low expansion substrate with a painted layer according to claim 10 or 11 , wherein the low expansion substrate is a quartz substrate.   The low expansion substrate with a painted layer according to claim 10, which is used as a top plate for a cooker.