JPH04325443A - Ceramic color composition and production of plate glass using the same - Google Patents

Abstract

PURPOSE:To obtain a plate glass not causing umber color development due to the migration of silver and having excellent appearance. CONSTITUTION:A layer 3 of a ceramic color compsn. contg. 40-90wt.% glass powder, 4-40wt.% heat resistant pigment powder and 1-30wt.% lead sulfide as inorg. components is formed on the surface of base plate glass 1. Bus bars 4 and heater wires 5 are further formed on the layer 3 with silver paste and sintered to produce plate glass.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic color composition and a method for manufacturing plate glass using the same.

0002

2. Description of the Related Art Hitherto, so-called ceramic color paste for automobiles has been widely used, which is made by pasting a ceramic color composition around or in the center of an automobile window glass, screen printing, drying, and baking in a bending process. This ceramic color paste is used to form a colored opaque layer by baking it onto the periphery of the base glass, and is used to prevent the urethane adhesive from deteriorating due to ultraviolet rays and to prevent the bonded area from being seen through from outside the vehicle. The composition for this purpose is known to be a mixture of glass powder and a heat-resistant colored pigment, and usually exhibits a black or dark gray color tone.

On the other hand, especially on the rear glass of a vehicle, a silver paste is printed in a line shape and baked as an electric heating heater to prevent fogging. The electrode forming portion of the heater (that is, the bus bar portion) may overlap in position with the baked portion of the ceramic color. Usually, in such cases, ceramic color paste and silver paste are overprinted and baked onto the plate glass.

However, in plate glasses manufactured by conventional methods, silver in the silver paste migrates through the ceramic color layer and reaches the plate glass.
It was inevitable that the color would develop into an amber color. Such coloration highlights the presence of the electrode portion of the silver paste, and is a problem as it significantly impairs the appearance of the vehicle window glass from outside the vehicle.

[0005]

OBJECTS OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and effectively prevents amber coloring by effectively preventing migration of silver in silver paste. The object of the present invention is to provide a ceramic color composition characterized in that it does not produce color, and a method for manufacturing plate glass using the same.

[0006]

[Means for Solving the Problems] The present invention provides a ceramic color composition containing inorganic components of 40 to 95% by weight of glass powder, 4 to 40% by weight of heat-resistant pigment powder, and 1 to 30% by weight of lead sulfide, and its use. The present invention provides a method for manufacturing flat glass.

The ceramic color composition of the present invention is mainly composed of the inorganic component having the above structure, and is made into a paste by containing an organic vehicle. By using such a ceramic color composition, vehicle window glass printed with this and then overprinted with silver paste will not develop an amber color due to silver migration even when fired in a normal bending process. , the aesthetic appearance from the outside of the vehicle is no longer impaired.

[0008] If the content of glass powder among the inorganic components of the ceramic color composition of the present invention is less than 40% by weight, the composition will not be baked onto the base glass. On the other hand, if it exceeds 95% by weight, the amount of components other than the glass powder, ie, pigments, borides, nitrides, carbides, etc., becomes too small, making it impossible to obtain the desired color tone or the effect of suppressing silver migration. Such glass powder is not particularly limited as long as it can be fused to the base glass by heating, and its composition is not particularly limited, including lead borosilicate, lead titanium silicate, bismuth borosilicate, and mixtures thereof. Various glass powders can be selected as appropriate.

[0009] Even when the application is limited to vehicles, glass powder with a similar composition can be used as appropriate, but especially in the case of vehicle window glass, the blank glass is often bent by pressing at the same time as baking. Manufacturing efficiency is particularly high when glass powder is used that easily separates from the press bending die. For example, this ceramic color composition can be fused to a substrate glass at 500 to 620°C, and
Glass powders which crystallize between 50 and 750°C are suitable for this purpose.

Specifically, for example, the following weight %
SiO2 in display
13 ~29Al2O3 +La2O3
0.1 ~ 5PbO
50 ~75TiO2+ZrO
2+SnO2 4~20B2O3
0 to 6
Li2O+Na20+K20 0
~ 5MgO +CaO +SrO +BaO
0 ~ 5P2O5
0-5F
By using a glass powder having a composition of 0 to 2, it is possible to obtain a ceramic color composition that is highly efficient in manufacturing plate glass for vehicle window glasses. The particle size of this glass powder is not particularly limited, but the average particle size is preferably 30 μm or less.

The reason why the above composition of the crystallized glass powder is preferable is as follows. SiO2: Glass network former, essential for controlling chemical, thermal, and mechanical properties. If it is less than 13%, chemical durability will be poor and undesirable. If it is more than 29%, the glass softening point becomes too high and it does not bake onto the glass surface at the desired bending temperature. Desirably 15-27%
It is.

[0012] Al2O3 +La2O3; Essential for improving chemical durability. If it is less than 0.1%, there is no effect. If it is more than 5%, the softening point of the glass will rise and baking will not occur at the desired temperature. Preferably 0.5~
It is 4%. PbO: essential as a flux component and a crystallization component; if it is less than 50%, the glass softening point becomes too high, which is not preferable. If it exceeds 75%, chemical durability deteriorates, which is not preferable. Desirably it is 52 to 73%.

TiO2+ZrO2+SnO2: Essential for crystallization and improvement of chemical durability, and if it is less than 4%, it is not preferable because it will not crystallize in the desired temperature range. If it exceeds 20%, it is not preferable because devitrification occurs during glass melting. It is preferably 6 to 18%. B23O: Although not an essential component, up to 6% may be introduced as a flux component. If it exceeds 6%, chemical durability deteriorates, which is not preferable.

[0014] Li2O+Na2O+K2O; Although not an essential component, up to 5% may be introduced as a flux component. If it exceeds 5%, the coefficient of thermal expansion becomes large, which is not preferable. MgO +CaO +SrO +BaO; Although not an essential component, 5 is added for the purpose of improving solubility and controlling the coefficient of thermal expansion.
It is possible to introduce up to %. If it exceeds 5%, chemical durability will deteriorate. P2O5: Up to 5% may be introduced for the purpose of improving chemical durability (especially acid resistance). If it exceeds 5%, devitrification occurs during glass melting, which is not preferable. F: Up to 2% may be introduced for the purpose of improving chemical durability (especially acid resistance). If it exceeds 2%, devitrification occurs during glass melting, which is not preferable.

[0015] Such glass powder has a temperature of 570 to 700°C.
It is a crystallized glass that precipitates in large amounts with lead titanate and lead silicate as the main crystals in the temperature range of . This temperature range corresponds to the temperature range in which soda lime-silica sheet glass, which is vehicle glass, is bent. Therefore, when the above-mentioned crystallized glass powder is applied to a desired part of a plate glass and the plate glass is heated and bent, the glass powder also crystallizes and the viscosity becomes higher in appearance.
It will not adhere to the press die of the bending machine.

If the content of the heat-resistant pigment in the inorganic components of the composition of the present invention is less than 4% by weight, the desired concentration of color tone cannot be obtained, while if it exceeds 40% by weight, the glass powder content becomes too small, resulting in poor burn-in on the plate glass. Such pigments may be the same as those used in conventional ceramic color compositions, and include copper chromium oxides, iron manganese oxides, iron oxides, titanium oxides, and the like. Although they do not impart color tone, conventionally used fillers such as alumina, silica, and zircon can also be included in the heat-resistant pigment.

[0017] Furthermore, it is important that the composition of the present invention contains a predetermined amount of lead sulfide powder as an essential component together with glass powder and a heat-resistant pigment as inorganic components. The anti-migration effect of silver is achieved.

The total content of lead sulfide in the inorganic components of the composition of the present invention is preferably 1 to 30% by weight. If it is less than 1% by weight, the effect of preventing silver migration will not be sufficient, while if it exceeds 30% by weight, the amount of glass powder will decrease, resulting in insufficient sticking to the base glass, both of which are undesirable. .

Although there are no particular restrictions on the synthesis method or purity of lead sulfide, the smaller the particle size, the greater the effect of inhibiting silver migration, and it is desirable that the average particle size is 30 μm or less.

The ceramic color composition of the present invention is prepared into a paste by homogeneously dispersing and kneading a predetermined amount of the above inorganic component and an organic vehicle in a conventional manner. here,
As this organic vehicle, polymers such as ethyl cellulose, acrylic resin, styrene resin, and phenol resin are used.
Those dissolved in solvents such as terpineol, butyl carbitol, acetate, and phthalate esters are used.

A plate glass using such a ceramic color composition is manufactured as follows. The above-described various inorganic components of the present invention and an organic vehicle are sufficiently kneaded to prepare a ceramic color paste. The viscosity of this ceramic color paste is 20,000 to 200,000.
A poise level is preferable in terms of workability.

Next, as shown in FIG. 1, a layer of the ceramic color paste is formed on a predetermined portion of the surface of the base glass by screen printing. When producing plate glass for vehicle window glass, the peripheral edge 2 of the surface of the raw glass 1 is usually coated with a thickness of 5 to 50 μm and a width of 10 to 10 μm.
A layer 3 of ceramic color paste of about 200 mm is formed. This layer 3 of ceramic color paste is then dried. Although such drying can be performed at room temperature, productivity can be improved by heating at 100 to 200°C for about 0.5 to 20 minutes. Further, drying can be accelerated by ultraviolet irradiation.

[0023] Next, in order to form an electrical heating heater for defogging on the surface of the glass plate, silver paste is printed on at least a part of the ceramic color paste layer 3, so that the ceramic color paste layer and the silver paste layer are printed. Make sure the layers overlap partially. The example shown in FIG. 1 is an example in which the bus bar 4 of the electric heating heater is hidden with ceramic color paste so that it cannot be seen from outside the vehicle, and a large number of linear heater wires 5 are formed between the bus bars 4. be. An example of such a silver paste is one in which an inorganic component consisting of 80 to 95% by weight of silver powder and 5 to 20% by weight of glass powder is mixed with the above-mentioned organic vehicle.

In the case of vehicle window glass, the silver paste layer used has a thickness of about 5 to 30 μm and a width of about 1 to 30 mm. Usually, silver paste is printed in a predetermined pattern even on areas where the ceramic color paste layer does not exist, that is, on the surface of the plate glass, to form antenna wires, heater wires, lead wires, etc. The layer of silver paste is then dried and fired to produce a glass plate having a ceramic color layer and a silver layer.

This firing may be performed under any conditions as long as the organic vehicle in the paste is removed and the glass powder is baked onto the substrate glass. When the plate glass is ordinary soda-lime-silica, such firing is performed at 550-750°C and 0.5°C.
This is achieved by holding for about 5 to 30 minutes. When manufacturing a plate glass for a vehicle window glass, it is preferable to perform heating for bending or at least a part of the bending at the same time as the above-mentioned firing step from the viewpoint of improving productivity. Specifically, in the heating step for firing,
It is preferable that the plate glass be heated or subjected to its own weight bending process for the next secondary bending process. Then,
If necessary, this sheet glass is subjected to press bending, droop bending, and air form bending.

[0026]

【Example】

Example 1 70% by weight of glass powder having the composition and particle size characteristics shown in Table 1, 20% by weight of black heat-resistant pigment (copper chromium oxide, manufactured by Dainichiseika Chemical Co., Ltd., #9510), lead sulfide (Kishida Chemical Co., Ltd.) Reagent (manufactured by Co., Ltd.) in an amount of 10% by weight. To 80 parts by weight of this mixed powder, 20 parts by weight of an α-terpineol solution containing 10% by weight of ethyl cellulose was added and kneaded, homogeneous dispersion was performed using a three-roll mill, and the desired paste viscosity was adjusted to form a paste. A ceramic color composition was obtained.

[0027]

[Table 1]

As a result, the color of the area printed with the ceramic color composition had no difference in tone between the area overprinted with the silver paste and the area without it, and could not be distinguished.

Example 2 Paste preparation, printing, and baking were carried out in the same manner as in Example 1 except that a mixed powder containing 77% by weight of glass powder, 20% by weight of black heat-resistant pigment, and 3% by weight of lead sulfide was used. I did it. Visually observing the baked plate glass from the unprinted side, there is no difference in color tone between the areas where the ceramic color composition is printed and the areas where the silver paste is overprinted and those where it is not. I couldn't tell the difference.

Example 3 Paste preparation, printing, and baking were carried out in the same manner as in Example 1 except that a mixed powder containing 60% by weight of glass powder, 20% by weight of black heat-resistant pigment, and 20% by weight of lead sulfide was used. I did it. Visually observing the baked plate glass from the unprinted side, there is no difference in color tone between the areas where the ceramic color composition is printed and the areas where the silver paste is overprinted and those where it is not. I couldn't tell the difference.

Comparative Example 1 Paste preparation, printing, and baking were carried out in the same manner as in Example 1, except that a mixed powder consisting of 80% by weight of glass powder and 20% by weight of black heat-resistant pigment without adding lead sulfide was used. Ta. Visually observing the baked plate glass from the unprinted side, the color tone of the area printed with the ceramic color composition is completely different between the area where the silver paste is overprinted and the area where it is not. was. The color tone of the non-overprinted area was almost the same as that of the example, but strong amber coloring was observed in the overprinted area.

Comparative Example 2 All examples were as in Example 1 except that a mixed powder containing 70% by weight of glass powder, 20% by weight of black heat-resistant pigment, and 20% by weight of zinc sulfide (reagent manufactured by Wako Pure Chemical Industries, Ltd.) was used. Paste preparation, printing, and baking were performed in the same manner as above. Visually observing the baked plate glass from the unprinted side, the color tone of the area printed with the ceramic color composition is completely different between the area where the silver paste is overprinted and the area where it is not. was. The color tone of the non-overprinted area was almost the same as that of the example, but strong amber coloring was observed in the overprinted area.

[0033]

Effects of the Invention When the ceramic color composition of the present invention is overprinted with a silver paste, it effectively prevents migration of silver during firing, so that no amber coloring occurs. Vehicle window glass with excellent aesthetic appearance can be obtained. Moreover, according to the present invention, a plate glass with excellent aesthetic appearance without such amber coloration is manufactured, and in particular, a vehicle window glass with excellent aesthetic appearance is manufactured.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a vehicle window glass manufactured according to the present invention.

[Explanation of symbols]

1　Base glass 3 Layer of ceramic color paste 4 Bus bar 5 Heater wire

Claims (4)

[Claims] Claim 1: The inorganic component is 40 to 95% by weight of glass powder;
A ceramic color composition comprising 4-40% by weight of heat-resistant pigment powder and 1-30% by weight of lead sulfide. 2. A ceramic color paste containing the ceramic color composition according to claim 1 is prepared, a layer of the ceramic color paste is formed on a part of the surface of the base glass, and at least one layer of the ceramic color paste is formed on the layer of the ceramic color paste. A method for manufacturing a plate glass, in which a layer of silver paste is formed covering a part of the glass, and then heated and fired, so that a ceramic color layer is formed on the surface of the base glass, and a silver layer is laminated on at least a part of the ceramic color layer. 3. A ceramic color paste containing the ceramic color composition according to claim 1 is prepared, a layer of the ceramic color paste is formed on a part of the surface of the base glass, and at least one layer of the ceramic color paste is formed on the layer of the ceramic color paste. A method for manufacturing a sheet glass for vehicle window glass, in which a layer of silver paste is formed covering a part of the glass, and then heated and fired, and a ceramic color layer is laminated on the surface of the base glass, and a silver layer is laminated on the ceramic color layer at least in part. . 4. A method for manufacturing a plate glass, characterized in that in the firing step according to claim 2 or 3, at least a portion of the base glass is subjected to bending.