JPH0214847A - Production of crystallized glass product - Google Patents

Abstract

PURPOSE:To eliminate unevenness of density of each part, to uniform crystallized glass products and to improve strength by setting a premolded article of special form in a special form part of a mold of special form, then packing and compressing glassy raw material powder and bonding both interfaces. CONSTITUTION:Glassy raw material powder is compression molded to give a molded article 4 of special form. The molded articles 4 are placed on special form parts 6 of a special form mold 5 of desired shape. Then the glassy raw material powder 8 is packed into a flat plate mold part 7 of the special form mold 5 and compression molded. Then a molded article of desired shape having the molded article 4 of special form and a flat plate part is obtained. This molded article is heat-treated, the whole molded article containing the bonding interfaces are sintered and crystallized.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a method for manufacturing crystallized glass products.

(Prior art) In the manufacturing method of crystallized glass products having a desired shape, methods for manufacturing products with complicated shapes include an integral compression molding method (conventional example 1) using a deformed mold, and a method for manufacturing products with a simple shape. A method of preparing multiple members and joining them using adhesive to form a desired shape (conventional example 2), preparing a plurality of members with simple shapes, and joining each member to form the desired shape. A method of installing and heating it to fuse and integrate it.
Publication No. 4-14132, Japanese Patent Application No. 60-284150)
The product is obtained by sintering and crystallizing the molded body formed by the above method.

(Problems to be Solved by the Invention) The method of Conventional Example 1 described above tends to cause density unevenness in irregularly shaped parts, and the method of Conventional Example 2 has different physical properties at the joint location.
In addition, in the method of Conventional Example 3, pinholes may remain in the joint part after firing due to insufficient density of the joint part during installation. Even with this method, it was difficult to obtain high-quality crystallized glass products with complex shapes.

(Means for Solving the Problems) As a means for solving the problems described above, the present invention provides a method for producing a crystallized glass product having a desired shape having an irregularly shaped part and a flat plate part. In order to form the powder, the glassy raw material powder is heated to room temperature or a predetermined temperature in advance and compression molded, and this irregularly shaped body is placed in the irregularly shaped part of the irregularly shaped mold having the desired shape. Filling a glassy raw material powder with substantially the same basic components as the glassy raw material powder and heating it to room temperature or a predetermined temperature and compression molding to obtain a molded body having a desired shape including the irregularly shaped body; We adopted a structure in which the entire structure, including the bonding interface, is sintered and crystallized by heat treatment.

In addition, in the present invention, since the above-mentioned configuration forms an irregular shaped body, the glassy raw material powder is compression-molded in advance and obtained directly, whereas the raw material powder is first compression-molded to create an elementary molded body, A configuration was adopted in which a deformed body was indirectly obtained by cutting this raw body.

In addition, the present invention provides a glassy raw material powder in which the essential components are 5i (h: 67-80%, CaO: 5% by weight).
~10%, Na, 0+KtO: 10-20%, Mg
O: 200 of a low softening point glass containing 2 to 8%
A highly softened powder comprising a powder with a particle size composition of 90% by weight or more of particles of mesh size or less, and essential components containing SiO□: 67 to 80%, 8LO3: 25% or less, NazO + KzO: 5 to 15%. Point glass powder with a particle size composition of 90% by weight or more of particles of 200 mesh or less,
A composition was adopted in which the former was mixed at a blending ratio of 90 to 20% by weight and the latter was the balance.

(Function) As shown in FIG. 3, the irregularly shaped body 4 is previously formed to have the same shape as the irregularly shaped part installed in the irregularly shaped part 6 of the irregularly shaped mold 5.
On the other hand, when a glassy raw material powder 8 is filled and compression molded as shown in FIG. 4, the flat plate portion 2 of the powder 8 is formed in tight contact with the irregularly shaped body 4.4. At this time, the powder particles microscopically penetrate into each other at the interface between the two to exert an anchoring effect, and no voids remain at the interface.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings. In the drawings, FIGS. 1 to 5 show the first embodiment of the present invention,
6 to 12 show the second embodiment.

The glassy raw material powder used in the present invention has the following essential components in weight percentage: 5iOz: 67-80%, CaO: 5
~10%, Na, O+ 20:10~20%, Mg
A powder having a particle size composition in which particles of 200 mesh or less of O: 2 to 8% account for 90% by weight or more, and Sing as an essential component in weight percentage: 67 to 80%, Δe2o3: 2
It is a high softening point glass containing 5% or less Na, and 0+ to 0+% Na-0+%.

The finer these glassy raw material powders are, the easier they are to be pressure-molded, and because the contact between powder particles is dense and the total contact area is large, the softening point of the powdered raw material glass is slightly exceeded during sintering. Since softening and fusion can be achieved at a relatively low temperature, and crystals are likely to precipitate at the fused interface of particles, a large amount of crystals will be precipitated during crystallization.

In the present invention, in order to ensure the effect of these glassy raw material powders, particles of 200 mesh or less are preferable, and in actual operation, particles of 200 mesh or less are 90
Powder having a particle size composition containing at least 50% of the weight may be used.

Next, in the present invention, the mixing ratio of the powders is 90 to 20% by weight of low softening point glass powder and the balance being high softening point glass powder. The reason for this is that if the content of the low softening point glass powder exceeds 90% by weight, the shaped body will not retain its shape sufficiently during heat treatment, while if the content is less than 20% by weight, the difference between different powders as described above The effect of promoting densification due to component transfer is small, and therefore densification is slow, requiring higher temperatures to promote it, and furthermore, densification may be insufficient.

That is, when the softening point of the high softening point glass powder and the crystallization temperature are close to each other, it is not possible to sufficiently prevent densification failure caused by crystallization.

Next, the essential component composition of the low/high softening point glass and the reason for its limitation will be shown. However, the crystals precipitated during heat treatment of the mixed powder compact of these glass powders are mainly SiO□ crystals.

A. Low softening point glass (unit: weight %, same below) Si
n,: 57-80% If it is less than 67%, 5i(h crystals will not precipitate), while if it exceeds 80%, the softening point will become high.

CaO: 5-10% If it is less than 5%, the softening point will be high, while if it exceeds 10%, SiO□ crystals will be difficult to precipitate.

NazO+KxO: 10-20% If it is less than 10%, the softening point will be high, while if it exceeds 20%, SiO□ crystals will be difficult to precipitate.

MgO: 2 to 8% If it is less than 2%, SiOg crystals grow too quickly and Na, (13cao.6SiO2 crystals, etc.) begin to precipitate.

On the other hand, if it exceeds 8%, 5iOz crystals will be difficult to precipitate.

B. High softening point glass SiO□: 67-80% If it is less than 67%, SjO□ crystals will not precipitate, while if it exceeds 80%, the softening point will become high.

Aj! zO: +: 25% or less If it exceeds 25%, 5i02 crystals will be difficult to precipitate.

NazO + KzO: 5-15% If it is less than 5%, the softening point will be too high;
If it exceeds 5%, the softening point becomes low.

The above-mentioned components are essential components in each glassy raw material powder, and each glassy raw material powder can contain a physical property adjusting component, a glass coloring agent, etc. in addition to these.

Next, the above specific glassy raw material powder (hereinafter referred to as powder)
This section describes pressure molding.

The pressure forming means of the present invention can be a cold press method in which pressure is applied using a mold at room temperature, or a high temperature press method in which a mold is used to heat and press the glass powder near its softening point.
In the room temperature pressing method, polyvinyl alcohol (
Mixing a binder such as PVA) improves moldability and strength of the molded product.

On the other hand, the high-temperature pressing method does not require the use of a binder, and a molded product with high strength can be obtained.

What is shown in Fig. 5 is a trapezoidal irregularly shaped part 1 and a flat plate part 2.
FIG. 3 is a cross-sectional view and a plan view of a molded body 3 of a crystallized glass product having the following properties before heat treatment. This molded body 3 is first made by compression molding a rod-shaped irregularly shaped body 4 having a trapezoidal cross section as shown in FIG. Create. Moreover, as shown in FIG. 2, this irregularly shaped body 4 is produced by first creating a raw molded body 4' having a shape similar to the irregularly shaped body 4 using a mold (not shown), and then cutting the raw molded body 4'. You can also try to get it.

The thus obtained irregularly shaped body 4 is placed in the irregularly shaped part 6 of the irregularly shaped mold 5 shown in FIG. The mold 5 consists of a lower mold 5a and an upper mold 5b, two irregularly shaped parts 6.6 are provided in the illustration, and the flat mold part 7 is appropriately filled with a powder 8 having substantially the same basic components as the powder. Then, compression molding is performed by heating the upper mold 5b to room temperature or a predetermined temperature.
As shown in the figure.

What is shown in FIG. 12 is a cross-sectional view of a molded body 13 (a second molded body to be described later) before heat treatment, which is a double-shaped crystallized glass product having a flat rectangular parallelepiped irregularly shaped portion 11 and a flat plate portion 12.12. FIG. This molded body 13 is first formed by compression molding a flat rectangular parallelepiped-shaped irregularly shaped body 14 as shown in FIG. Create. Next, this irregularly shaped body 4 is inserted into the irregularly shaped part 16 of the irregularly shaped mold 15 shown in FIG.
will be installed in

The mold 15 consists of a lower mold 15a and an upper mold 15b, and a flat mold part 17 provided in the lower mold 15a is suitably filled with a powder 18 having substantially the same basic components as the powder, and the powder 18 is heated at room temperature in the upper mold 15b. Alternatively, it is heated to a predetermined temperature and compression molded, and the state is as shown in FIG.

In this way, a first molded body 19 having a cross-sectional shape shown in FIG. 9 is obtained. In the above embodiments, the irregularly shaped body 14 is illustrated as having a very simple shape such as a flat rectangular parallelepiped for the purpose of explaining the present invention, but in reality it has a complicated shape.

The first molded body 19 described above is produced from the irregularly shaped body 14 through the steps shown in FIGS. 7 and 8, but as shown in FIG. 1 molded body 19
It is also possible to create a raw molded body 19° having a shape close to that of , and then to obtain the raw molded body 19° by cutting the raw molded body 19°.

Next, using a mold 20 as shown in FIG. 1I, the second molded body 13 shown in FIG. 12 is produced in the same manner as in FIGS. 7 and 8.

Next, heat treatment in the present invention will be explained.

Heat treatment usually involves raising the temperature of the compact 3.13 to the crystallization temperature, completing sintering during the same heating process, and once the crystallization temperature is reached, maintaining the same temperature to crystallize. It is also possible to use a method in which the sintering temperature is maintained in the range above or below the crystallization temperature, ie, the sintering temperature is maintained to complete the sintering, and then the temperature is increased, and the crystallization temperature is maintained to crystallize.

Thus, by sintering and crystallizing the entire molded body 3.13 including the bonding interface, a crystallized glass product having a desired shape having a deformed portion and a flat plate portion can be obtained.

Specific examples of the present invention will be shown below.

■ Composition of glassy raw material powder The chemical composition shown in the table below was used. However, A is a high softening point glass and B is a low softening point glass.

Table 1 (Unit double weight %) ■ Powder particle size of both A and B is 96% by weight of fine particles with a particle size of 200 mesh or less.

■ Powder mixing ratio, component molding temperature, component molding temperature are as shown in Table 2 below.

Next Table ■ Shape of molded body (Fig. 5) ■ Heat treatment 900°C It was confirmed that there were no cracks and that there was no overall density unevenness.

(Effects of the Invention) According to the present invention, since the irregularly shaped portion is manufactured separately, a uniform density can be obtained without unevenness in the density of the irregularly shaped portion, and the bonding interface between the irregularly shaped portion and the flat plate portion is firmly attached. , there are no pinholes at the interface after firing, and since substantially the same raw material powder is used for the irregularly shaped part and the flat plate part, there are no defects such as cracks at the interface, and there are no defects such as strength. No deterioration in physical properties.

Furthermore, the product obtained by the manufacturing method of the present invention can be used, for example, at a corner of an architectural pillar or wall, and has the advantage that the product value is high because the joints are not visible at all.

[Brief explanation of the drawing]

The drawings show the manufacturing method of the present invention, and FIGS.
FIG. 6 shows the first embodiment, and FIGS. 7 to 13 show the second embodiment. Figures 1 and 2 show the irregularly shaped body, Figures 3 and 4 are illustrations of compression molding, and Figure 5 is a cross-sectional view and a plan view of the product obtained by the method of the present invention before heat treatment, respectively. This is what is shown. Figures 6, 9, and 1O show the oddly shaped body;
FIGS. 8 and 11 are explanatory views of compression molding, and FIG. 12 is a sectional view and a plan view, respectively, of the product obtained by the method of the present invention before heat treatment. 1.11... Unusual part, 2,12... Flat plate part, 3
．． 13... Crystallized glass product Molded object before heat treatment, 4
．． 14... Irregular shaped body, 5, 15.20... Irregular mold, 8.18... Glassy raw material powder.

Claims (3)

[Claims] (1) When manufacturing a crystallized glass product with a desired shape that has an irregularly shaped part and a flat plate part, in order to form an irregularly shaped body having the same shape as the irregularly shaped part, the glassy raw material powder is heated in advance to room temperature or a predetermined temperature and then compressed. The irregularly shaped body is placed in the irregularly shaped part of a irregularly shaped mold having a desired shape, and then the flat plate part of the irregularly shaped mold is filled with a glassy raw material powder having substantially the same basic components as the glassy raw material powder. The molded body is heated to room temperature or a predetermined temperature and compression molded to obtain a molded body having a desired shape including the irregularly shaped body, and the molded body is heat-treated to sinter and crystallize the entire body including the bonding interface. A method for manufacturing a crystallized glass product characterized by the following. (2) When manufacturing a crystallized glass product with a desired shape that has an irregularly shaped part and a flat plate part, in order to form an irregularly shaped body having the same shape as the irregularly shaped part, the glassy raw material powder is heated in advance to room temperature or a predetermined temperature and then compressed. Molding to create a base molded body, then cutting the base molded body to obtain a irregularly shaped body, and installing this irregularly shaped body in the irregularly shaped part of a irregularly shaped mold having a desired shape,
Next, a glassy raw material powder having substantially the same basic components as the glassy raw material powder is filled into the flat mold part of the irregularly shaped mold, and the mixture is heated to room temperature or a predetermined temperature and compression molded to form the desired shape containing the irregularly shaped body. 1. A method for manufacturing a crystallized glass product, which comprises obtaining a shaped body, and subjecting the shaped body to heat treatment to sinter and crystallize the entire body including the bonding interface. (3) The glassy raw material powder contains SiO_2: 67-80%, CaO: 5-10%, Na as essential components in weight percentage.
A powder of low softening point glass containing _2O+K_2O: 10-20%, MgO: 2-8%, with a particle size composition of 90% by weight or more of particles of 200 mesh or less, and SiO_2 as an essential component in weight percentage: 67-80% Al_2O_3: 25% or less Na_2O+K_2O: 5-15% Powder with a particle size composition in which particles of 200 mesh or less account for 90% by weight or more,
Claim 1, characterized in that the glass powder is a mixture of 90 to 20% by weight of the former and the balance of the latter.
A method for manufacturing a crystallized glass product according to item 1 or 2.