JPH08277124A - Production of glass powder - Google Patents

Abstract

PURPOSE: To obtain a glass powder so as to enable the response to diversified small-quantity production at a low production cost by heat-treating a glass raw material powder mixed so as to afford a target composition at a temperature below the complete melting temperature. CONSTITUTION: Each raw material powder is weighed and mixed so as to provide a target composition in the method for producing a glass powder. The mixed powder is heat-treated at a temperature below the complete melting temperature for melting all the raw material powder to afford the objective glass powder. In the method for producing the glass powder, the heat-treating step corresponds to a melting and stirring step and a pulverizing step in a conventional process for producing the glass powder, the movement and diffusion of atoms among particles of the raw material powder are caused by heat- treating the raw material powder at the temperature below the complete melting temperature of the raw material powder to accelerate the vitrifying reaction and homogenization. Since the produced glass is in a powdery form, the pulverizing step is usually unrequired. When the glass powder having a finer particle diameter is required, the pulverizing step is required. The sufficiently mixed raw material is required in order to sufficiently initiate the vitrifying reaction.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing glass powder.

[0002]

2. Description of the Related Art Conventionally, for example, the production of glass powder which is used by being mixed with ceramic powder for a substrate for mounting electronic parts is
As shown in FIG. 2, the raw material powders were weighed so as to obtain the target composition, transferred to a platinum crucible, heated to a melting temperature of each raw material powder or more, completely melted and homogenized, It is rapidly cooled and solidified by dropping it in water or on a metal plate,
Further, a method of pulverizing so as to have a predetermined particle size was used.

[0003]

However, in the conventional manufacturing method, it is necessary to heat and homogenize each raw material powder at a temperature equal to or higher than the melting temperature. However, ordinary glass raw material powder contains silicon oxide, In order to completely melt the silicon oxide, it is necessary to heat it in the platinum crucible to a high temperature of about 1400 to 1500 ° C. and stir it for homogenization. For this reason, there is a problem that the furnace used for manufacturing is special and expensive, and there is a limit to reducing the manufacturing cost.

Further, according to the above-mentioned process, when a small amount of glass powder having a different composition is produced, the furnace and the quenching device have to be cleaned every time the composition changes, and the manufacturing cost per unit weight is very high. However, there is a problem that it is almost impossible to support a large number of small varieties.
Therefore, it is an object of the present invention to provide a glass powder manufacturing method which can be manufactured at low cost and can be used for small-quantity multi-product production.

[0005]

In the conventional method for producing glass powder, the raw material powders are mixed so as to have a target composition, the temperature is raised to a temperature at which all the raw material powders are melted, and further stirring is performed. Was needed. As a result of intensive studies conducted by the present inventors on this melting step, they found that the raw material powder was sufficiently vitrified and homogenized even at a temperature at which all the raw material powders were not completely melted, that is, even when part of the raw material powder was in a powder state. The present invention was conceived.

That is, according to the present invention, in the method for producing glass powder, after weighing and mixing the respective raw material powders so as to obtain the target composition, the mixed powder is heat-treated at a temperature below the complete melting temperature at which all the raw material powders are melted. And a method for producing glass powder. Further, in the method for producing glass powder, the step of weighing each raw material powder so as to have a target composition, the step of mixing, the step of performing a heat treatment at a temperature lower than a complete melting temperature at which all the raw material powder melts the mixed powder The manufacturing method is a method for manufacturing a glass powder, which comprises a step of pulverizing a powder which is further heat-treated as necessary. The steps of the method for producing glass powder of the present invention will be described in detail with reference to FIG. 1. First, a step of weighing each raw material powder to obtain a target composition, a step of mixing the raw material powders, a complete melting temperature of the raw material powders. It is composed of the following heat treatment steps. Alternatively, in addition to the heat treatment step, it comprises a step of crushing the heat-treated powder.

[0007]

In the present invention, the heat treatment process corresponds to the melting and stirring process and the crushing process in the conventional glass powder manufacturing process.
Heat treatment below the complete melting temperature of the raw material powder causes the movement and diffusion of atoms between the raw material powders, promotes the vitrification reaction and homogenization, and the produced glass is in powder form, so the pulverization process is Usually unnecessary. However, when a glass powder having a finer particle size is required, a crushing process is required. In order to sufficiently cause the vitrification reaction and homogenization, the raw material powders must be sufficiently mixed.
Further, since the reactivity depends on the particle size and surface condition of the raw material powder, the desired glass composition and particle size, etc., the temperature and time of the heat treatment conditions are appropriately determined according to the above parameters.

If the raw material powder used is finer, migration and diffusion between atoms are more likely to occur, and the particle size of the primary particles is 1 μm.
The following are preferred. However, it is not necessary to take the particle size into consideration because a substance soluble in water, such as boric acid, is dissolved during mixing in a ball mill and adheres to the surface of other particles. When using a raw material with a high content of silicon oxide with a high melting point,
Heat treatment at high temperature is required. Further, the particle size of the produced glass powder tends to increase as the heat treatment temperature increases. Even when a part of the raw material powder remains in the glass powder as a crystal phase of a carbonate or an oxide, this is because the above-mentioned heat treatment temperature is not appropriate and is included in the present invention.

[0009]

Embodiments will be described in detail below with reference to the flow of steps shown in FIG. (Example 1) The raw material powders of aluminum oxide, silicon oxide, calcium carbonate, strontium carbonate, lead oxide, sodium carbonate, and potassium carbonate were weighed so as to have a composition of Table 1 in terms of oxide so that the total amount was 1 kg. did. These were placed in a 5 liter ball mill pot, pure water was added, and ball mill mixing was performed for 20 hours. Next, the slurry was taken out of the pot, transferred to a stainless steel vat, and water was evaporated at 120 ° C. in a dryer. After the dried and solidified mixed powder was crushed in a mortar, it was placed in an alumina mortar and heat-treated in the air at 800 ° C. for 2 hours. When the diffraction pattern of the heat-treated powder was examined by an X-ray diffraction apparatus by the θ / 2θ method, only halo peculiar to glass was observed as shown in FIG.

[0010]

[Table 1]

(Example 2) Raw material powders of aluminum oxide, silicon oxide, calcium carbonate, strontium carbonate, and boric acid were weighed so as to have a total composition of 1 kg so as to have the composition shown in Table 2 in terms of oxide. Mixing, crushing, and heat treatment were performed in the same steps as in Example 1. However, the heat treatment was performed at a temperature of 850 ° C. for 2 hours. Next, in order to reduce the particle size of the heat-treated powder, the powder was put in a 5 liter ball mill pot, pure water was added, and the powder was crushed by a ball mill for 20 hours. Then remove the slurry from the pot,
It was transferred to a stainless steel vat and the water was evaporated at 120 ° C. in a dryer. Crush the dried and solidified powder in a mortar,
When the diffraction pattern of the crushed powder was examined by an X-ray diffractometer by a θ / 2θ method, only halo peculiar to glass was observed as shown in FIG.

[0012]

[Table 2]

[0013]

According to the present invention, as compared with the conventional manufacturing method, the furnace used may be a general one used in powder metallurgy such as ordinary ceramic products, and the maximum temperature is 1000.
Since the temperature is not higher than ℃, the equipment cost can be reduced significantly.
In addition, an expensive platinum crucible is not required, and it is possible to produce in an inexpensive alumina mortar. Furthermore, the crushing step is no longer an essential step. Therefore, the manufacturing cost can be significantly reduced.
Also, the glass material can be changed only by changing the alumina mortar and changing the temperature setting of the furnace, and it is possible to support a large variety of small quantities.

[Brief description of drawings]

FIG. 1 is a diagram showing a manufacturing process of glass powder in the present invention.

FIG. 2 is a diagram showing a manufacturing process of glass powder in a conventional technique.

FIG. 3 is an X-ray diffraction pattern diagram of the manufactured glass powder in the present invention.

FIG. 4 is an X-ray diffraction pattern diagram of the manufactured glass powder in the present invention.

Claims (3)

[Claims] 1. A method for producing a glass powder, wherein each raw material powder is weighed and mixed so as to have a target composition, and then the mixed powder is heat-treated at a temperature lower than a complete melting temperature at which all the raw material powders are melted. A method for producing glass powder. 2. In the method for producing glass powder, from the step of weighing each raw material powder so as to have a target composition, the step of mixing, and the step of heat-treating the mixed powder below a complete melting temperature at which all the raw material powders are melted. The method for producing glass powder according to claim 1, wherein the glass powder is produced. 3. The method for producing glass powder according to claim 2, further comprising the step of crushing the heat-treated powder.