JP2008192455A - Glass top plate for heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a glass top plate for a heating cooker capable of easily removing dirts such as oily scorched foods adhered to the surface and having a transparent coating layer with superior wear resistance and heat resistance without impairing appearance. <P>SOLUTION: The glass top plate 1 for the heating cooker is composed by laminating the coating layer 3 on a cooking surface 21 of a substrate glass 2 made of a low expansion crystallized glass plate. The coating layer 3 contains Zr and Al as main components. The coating layer 3 is preferably formed by coating a paste consisting of a metal resinate of Zr, the metal resinate of Al, and organic resin on the substrate plate 2, and then by calcining the coated paste at 500-900°C. The paste preferably further contains one or more kinds out of Bi, Sn, and In. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a glass top plate for a heating cooker.

  Conventionally, a glass top plate for a cooker made of a glass plate is installed on the top of a cooker such as an electromagnetic cooker or a gas cooker. An object to be heated such as a pan is placed on the glass top plate for the cooker, and the object to be heated can be cooked by a heating device inside the cooker. In particular, electromagnetic cookers tend to be increasingly demanded in recent years because of their high safety, and accordingly, the demand for glass top plates for cookers is also increasing.

In order to improve the antifouling property of such a glass top plate for a cooker, techniques (Patent Documents 1 to 4) relating to the antifouling film have been reported.
However, since the technique described in Patent Document 1 is a film composed of a siloxane bond, the film may be peeled off in a relatively short time due to friction with a cooking utensil such as a pan or a frying pan. Further, since it is easily affected by water, film formation under an anhydrous atmosphere is necessary, and there is a problem that the working environment is limited.

  Moreover, since the technique of the said patent document 2 has low baking temperature after coating as 100-700 degreeC, when a film | membrane is formed on the glass substrate whose softening point is 900 degreeC or more, it does not contain a flux component. Therefore, there is a possibility that the reaction between the film and the substrate becomes insufficient, the adhesion strength between the film itself and the glass substrate is weak, and there is a possibility that the film easily peels due to wear of an iron pan, a stainless steel pan, or the like. In addition, when printing is performed by a screen printing method using a water-soluble zirconium compound and a zirconium oxide sol, since the viscosity of the solution is too low, it is difficult to form a uniform printed film. In addition to the possibility of flowing into a non-uniform film, there is a problem in that continuous printability is poor.

  Moreover, since the technique described in Patent Document 3 is mainly composed of a fluorine compound, the heat resistance is poor, and when the temperature exceeds 500 ° C., there is a possibility of discoloration. In addition, there is a problem that scratches are likely to occur when rubbed or polished with an abrasive detergent or metal scrubber.

  Further, the technique described in Patent Document 4 is a technique for producing a film by a sol-gel method, a spray method, or a CVD method, but there is no problem when a film is formed on a transparent glass plate. When applied to a glass plate for an electromagnetic cooker, it has a drawback of lack of continuous workability and high cost.

  In addition, as a problem in a cooking device using an actual glass top plate, it is very difficult to remove a dirt such as a burnt oil such as salad oil. However, the structure required for the glass top plate that can easily remove such dirt such as oily scorching has not yet been clarified. Therefore, development of the glass top plate which can remove such dirt easily was desired.

JP 2006-8420 A JP 2005-321108 A JP 2003-51374 A JP 2000-86297 A

  The present invention has been made in view of such conventional problems, and it is possible to easily remove dirt such as oily scorch adhered to the surface, and to improve wear resistance and heat resistance. An object of the present invention is to provide a glass top plate for a heating cooker having a coating layer which is excellent, transparent and does not impair the appearance.

The present invention is a glass top plate for a cooking device in which a coating layer is laminated on a cooking surface of a substrate glass made of a low expansion crystallized glass plate,
The said coating layer exists in the glass top plate for heating cookers characterized by having Zr and Al as a main component (Claim 1).

  The coating layer of the glass top plate for a heating cooker of the present invention contains Zr and Al as essential components. Zr and Al have the property of improving dirt removal, and since Al has oil repellency, the glass top plate for a heating cooker is used on the surface by being used in the coating layer. It is possible to obtain an excellent effect that it is possible to easily remove the dirt such as burnt oil such as attached salad oil.

Moreover, since the coating layer is formed so that the Zr component and the Al component, which are main components, are in close contact with the substrate glass, the coating layer can have excellent wear strength and heat resistance.
Moreover, since the said coating layer becomes transparent and does not impair an external appearance, the said glass top plate for cookers becomes the thing excellent in the designability.

As a result, according to the present invention, it is possible to easily remove dirt such as burnt oil adhered to the surface, and it is excellent in wear resistance and heat resistance, is transparent and does not impair the appearance. It is possible to obtain a glass top plate for a heating cooker having
In addition, the said cooking surface is a surface which puts a pan etc. when using a heating cooker.

As described above, the glass top plate for a heating cooker of the present invention is formed by laminating a coating layer mainly composed of Zr and Al on the cooking surface of the substrate glass.
When the coating layer does not contain Zr, there is a problem that the stain removability is deteriorated and the design property is deteriorated such that the coating layer is clouded. On the other hand, when the coating layer does not contain Al, there is a problem that it is difficult to obtain removal performance against dirt such as oily scorch.

  Note that it is very difficult to clearly analyze the internal structure of a thin film such as the coating layer. On the other hand, in EPMA analysis etc., it is possible to detect the main components contained. In light of such a current situation, the coating layer in the present invention must contain “Zr and Al as main components” in the sense that it must contain both Zr and Al as constituent components. "Is used.

Next, the coating layer containing Zr and Al as essential components can be formed as follows.
That is, the glass top plate for the heating cooker is such that the coating layer is applied to the substrate glass with a paste made of a Zr metal resinate, an Al metal resinate, and an organic resin, and baked at 500 to 900 ° C. (Claim 2).

  In this case, in order to form a paste, for example, a coating method having excellent film formability such as a screen printing method can be performed. Therefore, it is not necessary to perform a sol-gel method, a spray method, a CVD method, or the like, which lacks continuous productivity and may increase costs, and a glass top plate for a heating cooker can be created by a simple method.

The metal resinate is a dilute solution of an organometallic compound and is a liquid having good dispersibility. Therefore, a uniform film can be formed when the coating layer is formed.
Examples of the organic resin include acrylic resins, amide resins, alkyd resins, and cellulose resins.

  Moreover, when the said calcination temperature is less than 500 degreeC, there exists a possibility that a uniform film | membrane with sufficient adhesive force cannot be formed. On the other hand, in the case where the firing temperature exceeds 900 ° C., there is a possibility that the substrate glass becomes cloudy when the substrate glass having β-quartz as a main crystal described later is used.

Moreover, the sum total of Zr content and Al content in the said paste is 1 to 10 weight%, and the ratio (Zr: Al) of Zr content and Al content is 99.9: 0.1. It is preferable that it is -50: 50 (Claim 3).
When the sum of the Zr content and the Al content in the paste is less than 1% by weight, the concentration is low, so that a phenomenon such as crease is likely to occur immediately after printing. There is a risk that a large number of portions where no layer exists). On the other hand, when the above sum exceeds 10% by weight, the film thickness (coating amount) of the coating layer is increased and the characteristics of the coating layer are maintained, but the transparency is partially lost or the iris color is reduced. There is a risk that the design will be reduced.
Thereby, the total of the Zr content and the Al content in the paste is more preferably 2 to 5% by weight.

  In addition, when the total of the Zr content and the Al content is 100% by weight, when the Al content exceeds 50% by weight, the problem that the dirt removal property is deteriorated, the coating layer becomes cloudy, etc. There is a problem that the designability is lowered. On the other hand, when the Al content is less than 0.1% by weight, the removability of dirt such as oily scorch may be lowered.

The paste preferably further contains one or more of Bi, Sn, and In (claim 4).
Bi, Sn, and In have an effect of further improving the adhesion strength when the Zr component and the Al component are adhered to the substrate glass. Therefore, by including one or more of these in the coating layer, the adhesive strength of the coating layer is improved, and further excellent wear strength and heat resistance can be obtained.

  When the paste contains one or more of Bi, Sn, and In, the Zr content in the paste, the Al content, and the total content of one or more of Bi, Sn, and In And the ratio of the total content of Zr and Al to the total content of one or more of Bi, Sn, and In (Zr + Al: Bi + Sn + In) is 99.9: 0. It is preferable that it is 1-60: 40 (Claim 5).

When the sum of the Zr content, Al content, and the total content of one or more of Bi, Sn, and In in the paste is less than 1% by weight, the concentration is low. Phenomena such as occurrence of repellency are likely to occur, and a large number of craters may be generated after firing. On the other hand, when the above sum exceeds 10% by weight, the coating layer becomes thicker and the properties of the coating layer are maintained, but the design properties such as partially losing transparency or exhibiting an iris color are exhibited. May decrease.
Thereby, the total of the Zr content, the Al content, and the total content of one or more of Bi, Sn, and In in the paste is more preferably 2 to 5% by weight.

Further, when the sum of the total content of Zr and Al (Zr + Al) and the total content of any one or more of Bi, Sn, and In (Bi + Sn + In) is 100% by weight, Bi + Sn + In is 60% by weight. When exceeding, there exists a possibility that stain | pollution | contamination removal property may deteriorate. On the other hand, if Bi + Sn + In is less than 0.1% by weight, the wear strength may be reduced.
Thereby, (Zr + Al: Bi + Sn + In) is more preferably 99.9: 0.1-60: 40.

In addition, the paste further includes one or more of Au, Pt, Pd, Rh, Mn, Ni, Fe, Cr, Ca, Si, Ba, Sr, Mg, Ag, and Ti, for a total of 5 weights. % Or less (Claim 6).
When these contain more than 5 weight% in total, there exists a possibility that the effect mentioned above of the said coating layer may deteriorate.

Moreover, it is preferable that the said coating layer is formed in the cooking surface whole surface or a part (Claim 7).
In this case, it is possible to easily cope with application by screen printing or the like.

The substrate glass preferably has a linear thermal expansion coefficient of −10 to 80 × 10 ⁻⁷ / ° C. (30 to 500 ° C.).
When the linear thermal expansion coefficient of the substrate glass is out of the range of −10 to 80 × 10 ⁻⁷ / ° C. (30 to 500 ° C.), there is a problem that it is not suitable as the substrate glass used for the glass top plate for cooking. is there.

The substrate glass preferably contains β-quartz solid solution and β-spodumene as the main crystal (claim 9).
The transparent low expansion crystallized glass plate having the β-quartz solid solution or β-spodumene as a main crystal is particularly suitable as a substrate glass for a glass top plate for a heating cooker.

Moreover, it is preferable that the decoration layer which consists of a glass composition and an inorganic pigment is formed in the upper surface of the said coating layer or between the said coating layer and the said substrate glass (Claim 10).
In this case, the design property can be improved without reducing the original strength of the substrate glass.
In addition, the glass composition is more preferably a lead-free glass composition in consideration of recyclability and the like.

  In addition, when a decorative layer is formed on the upper surface of the coating layer, the effect of suppressing the wear of the coating layer can be obtained, and therefore the wear resistance of the glass top plate for a heating cooker can be further improved. it can.

As said glass composition, it is preferable that a softening point is 650 degrees C or less. Moreover, it is more preferable to use a lead-free glass composition that contains SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , and Li ₂ O as essential components and crystallizes by heat treatment at 700 to 900 ° C.

Examples of the inorganic pigment include a white inorganic pigment, a black inorganic pigment, a gray inorganic pigment, a yellow inorganic pigment, a brown inorganic pigment, a green inorganic pigment, a blue inorganic pigment, and a pink inorganic pigment.
Specifically, as the white inorganic pigment, for _{example, TiO 2, ZrO 2, ZrSiO} 4, Al 2 O 3, 3Al 2 O 3 -2SiO 2, Li 2 O · Al 2 O 3 · 8SiO 2, Al 2 TiO _5, and the like.

Examples of the black inorganic pigment include Cr-Fe-based oxides, Co-Mn-Cr-Fe-based oxides, Co-Ni-Cr-Fe-based oxides, and Co-Ni-Cr-Fe-Mn-based materials. An oxide etc. are mentioned.
Examples of the gray inorganic pigment include Sn-Sb-based oxides and Sn-Sb-V-based oxides.

Examples of the yellow inorganic pigment include Sn-V oxides, Zr-V oxides, Zr-Si-Pr oxides, Ti-Cr-Sb oxides, and the like.
Examples of the brown inorganic pigment include Zn-Al-Cr-Fe-based oxides and Zn-Mn-Al-Cr-Fe-based oxides.

Examples of the green inorganic pigment include Ca—Cr—Si oxides, Cr—Al oxides, Co—Zn—Al—Cr oxides, and Zr—Si—Pr—V oxides. It is done.
Examples of the blue powder include Co—Al—Zn-based oxides, Co—Al-based oxides, and Zr—Si-based oxides.
Examples of the pink inorganic pigment include, for example, Mn—Al oxide, Ca—Sn—Si—.
Examples thereof include Cr-based oxides, Sn—Cr-based oxides, and Zr—Si—Fe-based oxides.

Moreover, it is preferable that the said decoration layer is formed so that it may become arbitrary patterns.
Examples of the arbitrary pattern include a dot shape, a line shape, and a solid having a certain area.

When the decoration layer is formed on the upper surface of the coating layer, the decoration layer is preferably a pattern having a small area so that the effect of removing dirt of the coating layer can be sufficiently exhibited.
On the other hand, when the decoration layer is formed between the coating layer and the substrate glass, the effect of removing the dirt of the coating layer is not reduced, and the shape of the decoration layer is not limited.

  Moreover, the decoration layer which consists of a glass composition and an inorganic pigment may also be formed in the surface on the opposite side to a cooking surface by a well-known method. In this case, the design of the top plate for a cooker provided with a coating layer having a stain removing effect can be improved by the decorative layer formed on the side opposite to the cooking surface.

(Example 1)
In this example, an example of the glass top plate for a heating cooker according to the present invention will be described with reference to FIG.
In this example, a glass top plate 1 for a heating cooker (sample E1) was produced as an example of the glass top plate for a heating cooker of the present invention.

As shown in FIG. 1, the glass top plate 1 for a heating cooker of this example is formed by laminating a coating layer 3 on a cooking surface 21 of a substrate glass 2 made of a low expansion crystallized glass plate.
This will be described in detail below.

As the substrate glass 2, transparent low expansion crystallized glass (Neoceram N-0) having β-quartz as a main crystal was used.
As the paste for the coating layer 3, a paste of Zr: 2.0% by weight and Al: 0.5% by weight composed of zirconium resinate, aluminum resinate, and ethyl cellulose was prepared.

Next, a manufacturing method will be described.
First, the coating layer paste was printed (applied) on the entire cooking surface 21 of the substrate glass 2 using a Tetron 380 mesh screen and baked at 800 ° C. to form the coating layer 3.
Moreover, in this example, although the said coating layer 3 was formed in the cooking surface 21 whole surface of the substrate glass 2, it may be a part.

(Example 2)
In this example, a glass top plate for heating cooker (sample E2) was produced as an example of the glass top plate for heating cooker of the present invention.
In this example, the paste for the coating layer of Example 1 is composed of zirconium resinate, aluminum resinate, bismuth resinate, and ethyl cellulose. Zr: 1.5 wt%, Al: 0.5 wt%, Bi : This is an example in which the paste was changed to 0.5% by weight.
Other than that was carried out in the same manner as in Example 1.

(Comparative Example 1)
In this example, a glass top plate for heating cooker (sample C1) was produced as a comparative example of the glass top plate for heating cooker of the present invention.
In this example, the coating layer paste of Example 1 was changed to a Zr: 2.0 wt%, Bi: 0.5 wt% paste composed of zirconium resinate, bismuth resinate, and ethyl cellulose. It is.
Other than that was carried out in the same manner as in Example 1.

(Comparative Example 2)
In this example, a glass top plate for heating cooker (sample C2) was produced as a comparative example of the glass top plate for heating cooker of the present invention.
In this example, the coating layer paste of Example 1 was changed to a Zr: 2.5 wt% paste composed of zirconium resinate and ethyl cellulose.
Other than that was carried out in the same manner as in Example 1.

(Comparative Example 3)
In this example, a glass top plate for heating cooker (sample C3) was prepared as a comparative example of the glass top plate for heating cooker of the present invention.
The glass top plate for a heating cooker of this example is such that the coating layer is not formed on the substrate glass of Example 1, and the transparent low expansion crystallized glass remains exposed on the cooking surface.

(Experimental example)
Next, the first scorching removal test for the glass top plates for the cooking device (samples E1 and E2, samples C1 to C3) and neo-serum N-0 produced in Examples 1 and 2 and Comparative Examples 1 to 3 A second burn removal test and a heat resistance test were performed to evaluate the performance. The results are shown in Table 1.

<First burn removal test>
In the first scorch removal test, first, salad oil is applied on the cooking surface of the prepared glass top plate for a heating cooker using kitchen paper soaked with salad oil, and then in an electric furnace at 300 ° C. for 30 minutes. Heated to make burnt.
After that, the cooking surface of the glass top plate for a heating cooker that has been sufficiently cooled is rubbed up to 20 times with a melamine sponge (material: melamine resin) to test whether the scorch can be removed. evaluated. A case where the evaluation is ○ is passed, and a case where the evaluation is × is rejected.

(Evaluation criteria)
○: When scoring can be removed within 20 round trips.
X: When scoring cannot be removed by 20 reciprocations.

<Second burn removal test>
In the second scoring removal test, first, the glass top plate for a heating cooker is heated in an electric furnace at 300 ° C. for 30 minutes, and then the glass top plate for the heating cooker is taken out from the electric furnace, Then, 3 drops of a solution adjusted to sugar: soy sauce = 1: 1 were dripped to prepare a burnt.
Then, it was cooled sufficiently, covered with scorch with a wet cloth width, allowed to stand for 10 minutes, and then rubbed with this wet cloth width at most 5 reciprocations to test whether the scorch could be removed, and evaluated the second scorch removability. An evaluation result of ◯ is accepted, and an evaluation result of x is rejected.

(Evaluation criteria)
○: When scoring can be removed within 5 round trips.
X: When scoring cannot be removed by 5 reciprocations.

<Heat resistance test>
Next, about the sample which passed the said 1st burning removal property and the said 2nd burning removal property, first, after heating the produced glass top plate for heating cookers at 600 degreeC for 20 hours, the surface state of the cooking surface Were visually observed to evaluate the surface condition. The evaluation is “good” and the “x” is rejected.
(Surface condition evaluation criteria)
○: When discoloration is not confirmed on the cooking surface.
X: When discoloration is confirmed on the cooking surface.

About what passed evaluation of the surface state, the above-mentioned 1st burning removal test was done similarly.
The heat resistance test is accepted when both the surface condition and the evaluation of the first burn removal test are ◯.

<Comprehensive evaluation>
When all evaluations in the first burn test, the second burn test, and the heat resistance test are acceptable, it is determined to pass (evaluation ○), and when any one fails, it is determined to be rejected (evaluation ×).

  As is known from Table 1, Sample E1 and Sample E2, which are examples of the present invention, were all good in the first burn removal test, the second burn removal test, and the heat resistance test. For this reason, it is possible to easily remove dirt such as oily scorch adhered to the surface, and it is excellent in wear resistance and heat resistance, and has a coating layer that is transparent and does not impair the appearance. The top plate could be produced by a simple technique.

Moreover, since the sample C1 and the sample C2 which are comparative examples of this invention do not contain Al so that it may be known from Table 1, the 1st burning removal property was disqualified.
Moreover, since the sample C3 as a comparative example of the present invention did not have a coating layer, the first burn removal property and the second burn removal property were unacceptable.

(Example 3)
In this example, as shown in FIG. 2, a decorative layer 4 is formed between the substrate glass 2 and the coating layer 3 of Example 1.
Specifically, using a paste made of a lead-free glass composition, an inorganic pigment, and an organic resin, a dot having a diameter of 0.65 mm and a pitch of 1 mm is used on the cooking surface 21 of the substrate glass 2 and a stainless steel # 350 mesh is used. Then, the decorative layer 4 was formed by coating by screen printing and baking at 800 ° C.

The lead-free glass composition contains SiO ₂ : 63 wt%, Al ₂ O ₃ : 12 wt%, B ₂ O ₃ : 20 wt%, and Li ₂ O: 5 wt% and has a softening point of 650 ° C. or less. A lead-free glass composition was used, a Co—Ni—Cr—Fe black pigment was used as the inorganic pigment, and a commercially available acrylic resin was used as the organic resin.
Thereafter, a coating layer 3 was formed in the same manner as in Example 1.

Explanatory drawing which shows the glass top plate for heating cookers in Example 1. FIG. Explanatory drawing which shows the glass top plate for heating cookers in Example 3. FIG.

Explanation of symbols

1 Glass top plate for cooking device 2 Substrate glass 21 Cooking surface 3 Coating layer

Claims (11)

A glass top plate for a cooker, in which a coating layer is laminated on a cooking surface of a substrate glass made of a low expansion crystallized glass plate,
The glass top plate for a heating cooker, wherein the coating layer is mainly composed of Zr and Al.   2. The coating layer according to claim 1, wherein the coating layer is formed by applying a paste made of a metal resinate of Zr, a metal resinate of Al, and an organic resin to the substrate glass and baking at 500 to 900 ° C. Characteristic glass top plate for cooking devices.   In Claim 2, the sum total of Zr content and Al content in the said paste is 1 to 10 weight%, and the ratio (Zr: Al) of Zr content and Al content is 99.9: It is 0.1-50: 50, The glass top plate for heating cookers characterized by the above-mentioned.   4. The glass top plate for a heating cooker according to claim 2, wherein the paste further contains at least one of Bi, Sn, and In.   In Claim 4, The sum total of Zr content in the said paste, Al content, and 1 or more types of total content in Bi, Sn, and In is 1 to 10 weight%, and Zr and Al The ratio of the total content and the total content of one or more of Bi, Sn, and In (Zr + Al: Bi + Sn + In) is 99.9: 0.1-60: 40. Top plate.   The paste according to any one of claims 2 to 5, further comprising: Au, Pt, Pd, Rh, Mn, Ni, Fe, Cr, Ca, Si, Ba, Sr, Mg, Ag, and Ti. A glass top plate for a heating cooker characterized by containing one or more kinds in total of 5% by weight or less.   The glass top plate for a heating cooker according to any one of claims 1 to 6, wherein the coating layer is formed on the entire cooking surface or a part thereof. In any one of claims 1 to 7, the substrate glass is heated cooker glass top, wherein the linear thermal expansion coefficient of ^{-10~80 × 10 -7 / ℃ (30~500} ℃) plate.   The glass top plate for a heating cooker according to any one of claims 1 to 8, wherein the substrate glass has a β-quartz solid solution and β-spodumene as a main crystal.   The decorative layer made of a glass composition and an inorganic pigment is formed on the upper surface of the coating layer or between the coating layer and the substrate glass according to any one of claims 1 to 9. Glass top plate for heating cooker.   The glass top plate for a heating cooker according to claim 10, wherein the decorative layer is formed to have an arbitrary pattern.

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