JPS608983B2 - Manufacturing method of low melting point glass with crystallization ability - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for producing a low melting point glass having crystallization ability for a milky white coating that can be baked at a low temperature of about 600o0 on glass plates, thin iron plates, aluminum plates, etc. Regarding.

The low melting point glass with crystallization ability produced by the method of this invention can be applied to a glass plate to turn transparent glass into opalescent glass, and can also be baked onto a thin iron plate or aluminum plate. If so, these can be made of steel plate enamel or aluminum enamel. Conventionally,
When applying a milky white coating, for example, enamel or glass enamel was used.

However, these have various drawbacks as described below. In other words, in the case of enamel, the baking temperature is generally high (800 to 85,000 ℃), and at least 75,000 ℃.
Therefore, it could not be applied to glass plates or thin steel plates. This is because such a substrate is thermally deformed at the enamel firing temperature. On the other hand, when using glass enamel, the raw material contains a large amount of POO, which has the disadvantage that it is difficult to dispose of what is discarded during the manufacturing process. Since pigments such as titanium oxide are mixed with the paint, the pigment particles in the paint film obtained by coating become coarse and a beautiful milky white color cannot be obtained. This invention was made in view of the above-mentioned circumstances, and it is intended to provide a crystal that, when printed on a glass plate, maintains its milky white color while still achieving a degree of opalescence that allows sufficient light to pass through. The purpose of the present invention is to provide a method for producing low-melting glass having the ability to convert.

That is, in this invention, the weight percent composition is 4.5SS.
i〇2 Mi34.013.5SB○3 Mi40.0 17.0SA1203 S42.0 15.0milR○○1R210S40.0 Here, R○' consists of Mg, Ca, Ba, Sr, and Zn. at least one selected from the group;
RI is at least one selected from the group consisting of Li, Na, and K.

After melting the glass consisting of 15.0 miSn020Ti020Zba]2S25.0, 0≦Sn02SI5.50STi02S23.0 0SZr○2mi20.5, "quenching by contacting with jet water" Its gist is a method for producing low-melting glass with crystallization ability.

Next, this will be explained in detail. In order to obtain a coating material with a fine and moderate milky white color, the inventors conducted various experiments and research, and found that the glass composition is of course important in achieving the desired milky white color. However, they also discovered that the manufacturing conditions for Gauss, especially the setting of cooling conditions, were extremely important, and after repeated experiments and research, they finally completed this invention.

This will be explained in more detail.

That is, since the glass having the above composition contains a large amount of opacifying agent in its raw materials, it has the property of being extremely susceptible to crystallization. Therefore, when this material is melted and then cooled by a normal cooling method such as being immersed in water, crystals form on the rapidly cooled surface due to the uneven cooling rate between the surface and the inside. , growth is inhibited and becomes relatively transparent, whereas in the interior where cooling is slow, crystals form and grow, and opalescence progresses. Therefore, even if such glass is crushed, slurried, painted, and baked, the milky whiteness varies from a microscopic perspective, so a fine milky white color cannot be obtained. However, the above molten glass,
When quenched by contact with gushing water, the molten glass is dispersed and made into fine particles upon contact with the gushing water, so each glass microparticle is rapidly cooled uniformly on both the surface and inside, making the entire glass transparent. becomes. That is, the generation and growth of crystals are inhibited throughout each glass particle, both on the surface and inside. Therefore, this glass particle is then finely pulverized, made into a slurry, painted, and baked.As mentioned above, this glass has the property of being easily crystallized, so many fine crystals are precipitated during this competitive firing. Therefore, fine-grained opalescence is achieved. This invention is configured as described above for the reasons described above.

That is, after melting the glass of the above composition, it is made to steepen by contacting it with jet water. It is possible to produce melting point glass. The raw material used in this invention may be any material as long as it becomes an oxide having the above composition or a mixture thereof upon firing.

For example, silicic anhydride, aluminum silicate, sodium sulfate,
Sodium chloride, soda carbonate, sodium silicate, boric acid, sodium borate, aluminum hydroxide, aluminum oxide,
Lithium carbonate, soda carbonate, lithium hydroxide, potassium carbonate, tin oxide, titanium oxide, zirconium oxide, sodium hydrogen carbonate, calcium carbonate, carnum hydroxide,
Examples include magnesium carbonate, barium carbonate, strontium carbonate, zinc oxide, magnesium chloride, magnesium oxide, magnesium hydroxide, magnesium sulfate, strontium sulfate, strontium oxide, barium sulfate, barium hydroxide, barium carbonate, and the like. In this invention, the low melting point glass having crystallization ability is specifically manufactured as follows.

(A) Appropriate materials are selected from the above-mentioned group of raw materials, and these are thoroughly ground and mixed at room temperature, with heating if necessary.

In this case, it goes without saying that the glass melting described below may be performed without pulverizing and mixing. {o} The above mixture is heated and fired in a furnace to melt and vitrify it.

800 to 130,000 at the final stage of glass melting
Continue to melt for 1 to 4 hours.

At this time, if necessary, worship at Nada may be done along the way. Day
Note that during the glass melting described above, pre-baking (calcination) may be performed as necessary.

For example, when using soda carbonate, boric acid, and zinc oxide, the raw materials are first thoroughly mixed and reacted at room temperature. At this time, heat as necessary. Next, 1 from 150 to 50,000
Dehydrate while heating and reacting for ~3 hours. In this way a solid is obtained. Next, crush this. Then, the first glass melting process is carried out. In this way, dehydration and decarboxylation hardly occur during glass melting, and therefore no bubbling from inside the rubbo occurs, which is safe and convenient. In addition to the above, even when materials containing water, carbonates, or ammonium salts are used as raw materials, it is preferable to perform pre-firing before melting.

The resulting glass melt is then quenched by contacting it with a jet of water. In this case, the supply ratio of the molten glass to the jet water is preferably 10 parts of the jet water to 1 part of the molten glass or more on a weight basis. This is because if it is less than this, cooling will be insufficient and it will be difficult to achieve the desired uniform cooling. In addition, the speed of the jetting water is 0
．． 4 m/sec or more is preferable. If it is less than this, it becomes difficult for the molten glass to become granulated, and therefore it becomes difficult to rapidly cool the entire particle. t
Finally, the obtained glass is finely pulverized using a pulverizer such as a pot mill, ball mill, or jet mill.
The desired low melting point glass 2 having crystallization ability is obtained.

The low melting point glass with crystallization ability obtained as described above is made into a slurry and coated on a substrate such as a glass plate, and
When baked at a temperature of about 0.000, a product with a beautiful milky white coating is obtained.

Next, embodiments of the invention will be described.

The composition of the glass raw materials used in each of the following examples is as shown in the table below. The composition of the low melting point glass obtained by the above formulation, expressed in oxide percentage, is as shown in the table below.

(Units are weight) Example 1 The raw materials were mixed and calcined at 35,000 for 30 minutes, then transferred to a Rubbo and melted for 2 hours in a firing furnace set at 1,200 to 130,000.

This molten glass was rapidly cooled by pouring it into running water spouting out at a rate of 5 per minute from an outlet with a diameter of 15 m/m at a flow rate of 300 m/min to form a frit. After drying, this frit was finely ground in a pot mill until it reached 200 mesh, made into a slurry, painted on a transparent glass plate (thickness 2h/m), and baked at 60,000 for 10 minutes, giving it a beautiful milky white appearance. A glass plate was obtained.

On the other hand, in order to compare with this, an attempt was made to opacify a glass plate using the molten glass that had been cooled by placing it in standing water, but there was variation in crystallization. Beautiful opalescent glass could not be obtained.

Example 2 After mixing the blended Tsukuda raw materials and calcining them at 35,000 for 3 minutes, they were transferred to a Rubbo and melted for 2 hours in a firing furnace set at 1,200 to 1,300 o.

This molten glass was rapidly cooled by pouring it into running water jetting out at a flow rate of 10 m/min from an outlet with a diameter of 15 m/m at a flow rate of 300 m/min to form a frit. When a transparent glass plate was opalized using this frit in the same manner as in Example 1, a beautiful opalescent glass could be obtained.

Example 3 The raw materials were mixed and pre-brined at 35,000, and the same treatment as in Example 1 was carried out to obtain a frit, which was used to make transparent glass in the same manner as in Example 1. When the plate was opalized, a realistic opalescent glass could be obtained in this case as well.

Claims (1)

[Claims] 1 Composition expressed in weight% is: 4.5≦SiO_2≦34.0 13.5≦B_2O_3≦40.0 17.0≦Al_2O_3≦42.0 15.0≦RIIO+R_2IO≦40.0 Here , RII is at least one selected from the group consisting of Mg, Ca, Ba, Sr, and Zn,
RI is at least one selected from the group consisting of Li, Na, and K. 15.0≦SnO_2+TiO_2+ZrO_2≦25
．． 0 However, 0≦SnO_2≦15.50≦TiO_2
≦23.0 0≦ZrO_2≦20.5 A method for producing a low melting point glass having crystallization ability, which is characterized by melting glass and then rapidly cooling it by contacting with jet water. 2. The method for producing a low melting point glass having crystallization ability according to claim 1, wherein the supply ratio of molten glass to jet water is set to 1 part molten glass to 10 parts jet water or more on a weight basis. 3. A method for producing a low melting point glass having crystallization ability, as set forth in claim 1, wherein the speed of the ejected water is set to 0.4 m/sec or more.