JPH0193440A - Production of crystallized glass having color pattern - Google Patents

Abstract

PURPOSE:To readily produce a crystallized glass having mosaic pattern, by blending and accumulating two or more kind of glass particulate bodies having different colors and molding the particulate bodies under pressure and then sintering and crystallizing the moldings. CONSTITUTION:0.05-5wt.% coloring agent is added to a glass powder consisting of 90-20wt.% glass powder having low softening point containing 67-80wt.% SiO2, 5-10wt.% CaO, 10-20wt.% Na2O+K2O and 2-8wt.% MgO and 10-80wt.% glass powder having high softening point containing 67-80wt.% SiO2, <=25wt.% Al2O3 and 5-15wt.% Na2O+K2O to afford two or more kind of particulate bodies 1, 1a and 1b having different colors. Then the particulate bodies 1, 1a and 1b are blended and accumulated and molded under pressure to provide the moldings having mosaic pattern 2 and 2a, which is then heat- treated, sintered and crystallized.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing colored patterned crystallized glass suitable as an interior/exterior material for buildings.

(Prior art) As a method for obtaining crystallized glass with colored patterns,
No. 5-29018, a glass body (1
~ 7m) and heat-treating it to sinter and crystallize the aggregated bodies (hereinafter referred to as the accumulation method), a method in which colored glass bodies are mixed in the accumulated bodies,
The applicant proposed in "Japanese Patent Application No. 61-2693" that a fine glass powder capable of precipitating a wollastonite product is mixed with coarse colored glass particles and molded.
There is a method of heat treatment for sintering and crystallization. This method takes advantage of the fact that crystals tend to precipitate at the fused interface of powder particles to be sintered (this method is hereinafter referred to as the sintering method). (also applicable.

(Problems to be Solved by the Invention) Regardless of the above-mentioned accumulation method or sintering method, the formation of a colored pattern is due to mixed colored glass bodies and coarse particles, and the pattern is a mottled pattern. It is not possible to form mosaic patterns, which are often used as patterns, and the mottled spots themselves become large.If there are too many colored glass particles or coarse particles mixed in, air bubbles may be generated during sintering. For example, colored glass powder with a size larger than 10 mesh is not preferred in the sintering method.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing crystallized glass that can easily form a mosaic pattern.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following features: The number of particles of 200 mesh or less is 90! Two or more types of granules with different colors are molded using glass powder having a particle size composition that accounts for ii% or more, and then the granules are mixed and aggregated and pressure-molded to form a molded body, and then the molded body is They adopted a method of heat treatment to achieve sintering and crystallization.

(Function) The glass powder used in the present invention has a particle size composition in which fine powder of 200 mesh or less accounts for 90% by weight or more,
In a molded body made of such fine powder, the contact area between the powders is extremely large overall, and fusion and densification between the powders can be easily performed at a relatively low temperature during sintering.

On the other hand, in the case of coarse grains, gaps are created between adjacent particles and the contact area is small, and fusion densification during sintering does not proceed unless the temperature is significantly higher than the softening point, and the gaps are closed by sintering. They tend to remain as cavities after sintering.Crystallization may progress considerably during high-temperature sintering, and in such cases, sintering is hindered by the increase in viscosity that accompanies this progress.

In other words, in the present invention, the use of fine powder of 200 mesh or less,
By ensuring low-temperature sintering that is slightly above the softening point, crystallization does not occur during the sintering period, and fusion and densification can proceed sufficiently.

In addition, since crystals tend to precipitate at the fused interface of powder,
The use of the fine particles increases the size of the fused interface, and a large number of crystals precipitate. In other words, crystallization becomes easier,
Not only glasses with compositions that are easy to crystallize, but also glasses that are not easily crystallized can be used as raw material powders.

The mosaic pattern is formed by integrating and bonding two or more different colored granules (coloring will be described later) molded from the glass powder.

Below, pattern formation will be explained with reference to the drawings. Figures 1 to 3 are explanatory diagrams of the mosaic pattern formation described above, taking as an example the case where granules of three different colors are used. Granules with different characteristics 1. When 1.1a and 1.1b are mixed and accumulated as shown in FIG. 1, and then pressure-molded, the granules 1.1a and 1.1b are deformed and their boundaries are brought into close contact and integrated as shown in FIG. In other words, a molded body is formed by assembling granules, and therefore granules of different colors 1. la,
lb forms a mosaic pattern 2.

When such a molded body is sintered and crystallized, the mosaic pattern 2 is maintained, the glass particles are fused and densified, and crystals are precipitated to form crystals having a mosaic pattern 2a as shown in FIG. Thus, chemically modified glass can be obtained.

(Example) First, the glass powder used in the present invention will be described.

As for the glass to be made into powder, as mentioned above, not only glasses that easily precipitate crystals, but also glasses that do not can be used, and the range of applications is wide, and for example, soda lime glass, which is a normal glass, can also be used.

Regarding the refining of glass powder, appropriately crushed glass corpuscles can be refined using, for example, a ball mill, and the particle size can be reduced to 90 m2 or less.
As already mentioned, the reason for limiting the powder to particles with a particle size composition of 100% or higher is to ensure low-temperature sintering and to easily precipitate a large amount of crystals during crystallization after sintering. be.

However, in order to obtain powders with different colors, it is possible to make a difference in the type and amount of the glass coloring agent mixed with the powder. Glasses of different colors may be used as powders.

As colorants, oxide powders such as MnO, Cod, and Fe20m are usually used, and the amount of addition depends on the coloring effect, whether added to the glass powder or mixed into the glass raw material to make colored glass. It is preferably 0.05% by weight or more, and 5% by weight or less since it may affect the shrinkage rate and cause cracking during heat treatment.

Note that the above-mentioned difference in color includes not only a difference in color (including a combination of colorless and colored), but also a difference in shading and brightness even if the color is the same.

Next, we will discuss the formation of granules using the powder whose particle size and color have been adjusted as described above.Water or a binder such as polyvinyl alcohol (PVA) is added to the powder and mixed well to form granules. In order to ensure the shape of the mosaic pattern, it is desirable that the size is φ1 or more, but if the size exceeds φ30, the gaps between the accumulated granules will become large, and these large gaps will be removed by pressure forming. Because it tends to remain as a cavity even after time and sintering, φ30
It is desirable that the thickness be less than mm.

The thus obtained granules are collected in a pressure mold, pressure molded, and then heat-treated.

Pressure forming can be performed by cold pressing performed at room temperature or by hot pressing performed by heating near the softening point of the glass powder.
The heating temperature for hot pressing is usually a temperature slightly below the softening point.

Heat treatment can be a two-stage process in which a primary heat treatment is performed for the purpose of sintering, and then a secondary heat treatment is performed for the purpose of crystallization by further increasing the temperature. It is also possible to use a one-stage process in which the process is completed midway to achieve post-crystallization.

By the way, if the difference between the softening point and the crystallization temperature of the glass used as powder is too large, it will be difficult to maintain the shape when the pressure-formed body is heated to the crystallization temperature after sintering. If the difference between the softening point and the crystallization temperature is too small, the sintering temperature will substantially overlap the crystallization temperature range, causing sintering failure due to increased viscosity due to crystal growth.

However, in order to solve these problems, the present inventors discovered that the glass powder has a large difference in softening point and crystallization temperature, and does not rely on a single glass powder.
By using a mixed powder of a low softening point glass powder with a low softening point and a high softening point glass powder, the low softening point powder is softened and fused at low temperatures to achieve integrated densification of the powder. The decrease in shape retention due to the accompanying decrease in the viscosity of the particles is compensated for by the coexisting unsoftened or softened high softening point glass powder, and crystallization is allowed to proceed after sufficient progress of fusion and densification. Good results have been obtained, and the suitable mixed powder of low and high softening point glass powder contains the following essential components in weight percentage: Stow: 67-80%, CaO: 5-10%
Na20+20: 10-20%, MgO=
Low softening point glass powder containing 2 to 8%, and as essential components in weight percentage, SiO□ = 67 to 80%, Am or less than 225%, Na2
0+ and a powder of high softening point glass containing 5 to 15% of o: to obtain a powder consisting of 90 to 20% by weight of the low softening point glass powder and the balance of the high softening point glass powder. The reason for limiting the components of the low-high softening point glass and the mixing ratio will be explained below.

Incidentally, the crystals precipitated during the sintering and crystallization treatment of the mixed powder are mainly StO□ crystals.

Low softening point glass 5iOz: 67-80% If it is less than 67%, 5in2 crystals will not precipitate, while if it exceeds 80%, the softening point will become high.

CaO: 5 to 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.

Na20+20: 10-20% If it is less than 10%, the softening point will be high, while if it exceeds 20%, 5in2 crystals will be difficult to precipitate.

? 1gO: 2-8% If it is less than 2%, the growth of SiO□ crystals becomes too fast, and Nazo.3CaO.6SiO□ crystals etc. are precipitated. On the other hand, if it exceeds 8%, 5i02 crystals will be difficult to precipitate.

High softening point glass 5iOz: 67-80% If it is less than 67%, SiO□ crystals will not precipitate, while if it exceeds 80%, the softening point will become high.

to ρ, 01:25% or less If it exceeds 25%, Sigh crystals will precipitate.

Na20+ and 2o: 5-15% If it is less than 5%, the softening point will be too high, while if it exceeds 15%, the softening point will be low.

Note that the difference in softening point between the two glasses is preferably 50 to 700°C. In other words, if the temperature is lower than 50°C, there is a strong possibility that both powders will soften as the temperature rises to the crystallization temperature of the compact, making it difficult to maintain their shape, and if the temperature exceeds 700°C, the high softening point component will shift to the low softening point powder side. As a result, the transition becomes slow, and in practice, it is impossible to expect the shrinkage of the molded article to be promoted.

Next, the mixing ratio of the above-mentioned low/high softening point glass powder will be described.

Needless to say, the particle size of both powders is the same as in the case of a single powder, with 90% by weight of fine particles of 200 mesosinus or less.
The reason why the mixing ratio is 90 to 20% by weight of low softening point glass powder and the balance being high softening point glass powder is because the low softening point glass powder is 90% to 20% by weight.
This is because if it exceeds 20% by weight, the shape retention of the molded product will be insufficient during heat treatment, while if it is less than 20% by weight,
The densification promoting effect due to the component migration of the high softening point components to the low softening point powder side as described above is small, and therefore densification is delayed.
In order to promote the process, a higher temperature is required, and furthermore, insufficient densification may occur. That is, when the softening point and crystallization temperature of the high softening point glass powder are close to each other, densification failure caused by increased viscosity due to crystallization cannot be sufficiently prevented, resulting in insufficient densification.

Next, specific examples of the present invention will be shown.

Table 1 below shows the compositions of the low softening point glass powder A and the high softening point glass powder B used in the examples.

The particle size is A...97% B...200 mesh or less.
・200 mesh or less is 99% Table 1 The above raw material powder A is mixed at a ratio of 60% by weight and the balance is B, and from this mixed powder C, the following three different colored powders from ■ to ■ are obtained. Ta.

■・・・・・・Mixed powder C above.

■・・・・・・Fe20 as a coloring agent in the above mixed powder C
A colored mixed powder containing 1.0% by weight of 1 powder.

(2) A colored mixed powder obtained by mixing the above mixed powder C with 0.3% by weight of NiO powder as a coloring agent.

Add polyvinyl alcohol as a binder to each of the above three types of powder and mix well.
Form into 4-fin granules, mix these granules, aggregate in a mold, and pressurize at room temperature to form 150 x 150 x 25 m.
A plate-shaped molded body of m was obtained. Pressure force is 250 kg, f/
It was crA.

The thus obtained molded body was subjected to 900·'CX151trO heat treatment, sintered and crystallized to obtain crystallized glass,
The flat surface of the same glass was polished. A white, red, and yellow-green mosaic pattern was formed on the polished surface, and the precipitated crystals were mainly SiO□ crystals.

(Effects of the Invention) As explained above, in the present invention, a granular body made of fine glass powder of different colors is formed, and the formed body obtained by accumulating and pressing the granules is sintered and crystallized. Various mosaic patterns can be easily formed by changing the size of the particles, color combinations, etc.

In addition, the formation of color patterns in conventional accumulation methods and sintering methods is due to the colored glass particles and coarse particles interposed in the base glass particles and fine powder, respectively, and the effect on sintering is that the color patterns are formed by The size of the formed body is extremely limited, but in the present invention, the unit pattern is a granular body made of fine powder, so there is no particular influence on sintering or crystallization (the size is much larger than in the past). A unit pattern can be formed.

In addition to the above, the use of fine powder of 200 mesh or less allows low-temperature sintering and easy crystallization, making it suitable for manufacturing large-scale crystallized glass building materials, and has many advantages. The industrial value of the present invention is significant.

[Brief explanation of the drawing]

1 to 3 are explanatory diagrams of mosaic pattern formation according to the present invention, and FIG. 1 is a diagram showing a state of mixed accumulation of granules of different colors;
FIG. 2 is a diagram showing the state of a pressurized aggregated granular body, and FIG. 3 is an example of a mosaic pattern in crystallized glass. 1, la, Ib...granular material, 2, 2a... mosaic pattern. Patent applicant: Kubota Iron Works Co., Ltd. Figure 3

Claims (2)

[Claims] (1) Molding two or more types of granules with different colors using glass powder having a particle size composition of 90% by weight or more of particles of 200 mesh or less, then mixing and aggregating the granules, and press-molding. A method for producing crystallized glass with colored patterns, which comprises forming a molded body and then heat-treating the molded body to achieve sintering and crystallization. (2) The above glass powder contains SiO_2: 67-80%, CaO: 5-10%, Na as essential components in weight percentage.
_2O+K_2O: 10-20%, MgO: 2-8%,
and a high softening point glass powder containing as essential components SiO_2: 67-80%, Al_2O_3: 25% or less, Na_2O+K_2O: 5-15%. The colored patterned crystal according to claim 1, wherein the glass powder is made of 90 to 20% by weight of the low softening point glass powder and the balance is the high softening point glass powder. Method for producing chemical glass.