JPS62162631A - Production of crystallized glass having colored pattern - Google Patents

Abstract

PURPOSE:To obtain a crystallized glass having spotted color pattern without necessitating specific component, by compression-molding a mixture of colorless glass powder and colored glass powder having different particle size and heating the molded mixture to effect the softening, fusion, integration and densification of each glass powder and, at the same time, crystallizing the mixture. CONSTITUTION:(1) A vitreous raw material containing 45-75% SiO2, <=20% Al2O3, 5-40% CaO and 2-20% Na2O+K2O as essential components (the sum of the above components is >=85%) is crushed to obtain powder containing particles of >=200 mesh accounting for >=90%. (2) A colored vitreous raw material composed of each component of the above composition and <=10wt% colorant is crushed to obtain powder of 10-200 mesh or powder containing particles of 10-200 mesh and >=200 mesh. (3) Both powdery compositions (1) and (2) are mixed together. The amount of the particles of <=200 mesh in the mixture is >=50%. (4) The mixture is compression molded to obtain a pressed powder having desired shape and a density of >=55% of the true density. (5) The molded article is heat-treated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing crystallized glass having a color pattern.

(Prior art) Conventional crystallized glass is generally produced by melting a glass raw material containing a nucleating agent, molding it using various molding machines, etc., and then subjecting it to crystallization heat treatment to precipitate crystals. It has a white color. Colored crystallized glass can be produced by adding a glass coloring agent to the above raw materials.

Another method for obtaining crystallized glass is to obtain glass corpuscles by crushing molten glass by cooling with water, etc., and by gathering the glass corpuscles in a mold and heat-treating them, each glass corpuscle is fused. A method of integrating and crystallizing (hereinafter referred to as the integration method) is disclosed in ``Japanese Patent Application Laid-Open No. 78217-1978, and the crystallized glass produced by this method has a white color with a pattern due to uneven crystal growth. It is.

In addition, also in this accumulation method, it is also possible to obtain colored crystallized glass by using colored glass in which a glass colorant is added to the raw glass.

(Problems to be solved by the invention) Generally, glass is a material with a problem in terms of strength, and improvements in its strength are always sought after.Also, the diversification of decorative materials, construction materials, etc. has caused uniformity in colored glass as well. The emergence of glass that is not colored but has a change, for example, a glass that exhibits a mottled pattern, is expected, and from this point of view, melting and forming the glass raw material containing the nucleating agent and the glass coloring agent is expected. The problem with the method of precipitating crystals by post-crystallization heat treatment is that the coloring is uniform and the nucleating agent is sometimes expensive compared to the raw materials. Patterns are created by the growth of non-uniform crystals, but when the glass bodies are heated, the viscosity is low enough that the glass bodies can be fused together and integrated at the temperature at which the crystals precipitate. It is not suitable unless you have the following. There are limitations to the raw material glass, so colorants that also act as nucleating agents or nucleating agents, such as FeS + MnS + FeO + Fe2
Glass bodies containing 01 and the like cannot be used.

In other words, in a heated glass body, the growth rate of the crystal nuclei precipitated at the softening temperature is fast, and if the composition is such that the crystals grow before fusion, or if it contains a nucleating agent as described above, The viscosity increases due to the growth of crystals, and the glass bodies cannot be fused and integrated, and if an attempt is made to further increase the temperature to achieve integration, the crystals will instead break or transfer and will not become crystallized glass. It is.

Furthermore, this accumulation method has the problem that the color does not come out clearly even when colored with a coloring agent that does not act as a nucleating agent, and that the product contains relatively large bubbles (diameter of 0.5 mm or more). It also has

(Measures to Solve the Problems &) The present invention solves the problems of the prior art as described above without requiring any special ingredients, and provides crystallized glass with a mottled color pattern. As a means for that purpose, as an essential component, 5i0
2: 45-75%, ^Q*01: 20% or less, C
aO: 5 to 40%, 20 to Na2O+: 2 to 20%, 20 to 5ift+^R*01+CaO+Na20+
>85% of the glassy raw material is crushed so that particles of 200 mesh or less account for 90% or more, and each component in the above composition range and the weight percentage is 10% or less. When mixing a powder containing particles of 10 to 200 mesh or 10 to 200 mesh and smaller by pulverizing a colored glassy raw material containing a coloring agent, in the mixture of the two. The two are mixed in a desired ratio within a range in which particles of 200 mesh or less account for 50% or more, and then the mixture is compression-molded into a green compact with a true density of 55% or more using a compression molding frame of a desired shape. Thereafter, by heat treatment, the glass powders of the green compact were softened and fused to each other, integrated and densified, and crystallized to precipitate mainly wollastonite crystals.

(Function) The most characteristic technical means of the present invention is to turn the glassy raw material into a fine powder, make it into a dense compression molded body, post-heat it, and soften and fuse each glass powder to integrate and densify it. On the other hand, it is aimed at crystallization, but the pulverization of the glassy raw material and the creation of a dense compacted body work so that softening and fusion between the glass powders can easily occur at a relatively low temperature. There is.

In other words, when coarse glass particles are simply accumulated and heated, even when the softening point is reached, the particles do not immediately fuse and become integrated. First, the sharp corners of each particle begin to soften, and in order to soften almost the entire particle, it must be heated to a high temperature above the softening point, and it is only when heated to such a high temperature that fusion and integration occur. It is.

However, in the case of a dense compacted body of fine powder, each particle is in close contact with each other over a large area relative to its mass, and it is extremely easy to fuse and integrate the particles, resulting in progress in densification.

The fact that it is now possible to integrally densify glass particles at a relatively low temperature means that crystal growth can be achieved after integral number densification, and this successfully solves the problems of conventional integration methods. Even if a nucleating agent or a coloring agent that acts as a nucleating agent is included, crystallization can be achieved after the green compact particles are densified, and furthermore, during the crystallization, the contained nucleating agent works effectively.

Figure 1 is a graph conceptually showing the relationship between temperature, nucleation rate, and crystal growth rate when heating a compressed glass fine powder, with the nucleation rate and crystal growth rate plotted on the vertical axis, and the horizontal axis. The temperature is measured on the shaft.

The broken line is the "nucleation rate vs. temperature" curve, and the solid line is the "crystal growth rate vs. temperature" curve. In addition, s, p are softening points, M
, P is the melting point.

As mentioned above, when heating a compacted glass powder, each glass particle is fused and integrated and densified at a relatively low temperature that does not exceed its softening point, and it is during this period that nuclei are generated. The graph shows that the number increases, and as the temperature increases thereafter, crystal growth becomes more active.

Next, to mention another effect of forming a compact compact of fine powder, even glass with a composition that is difficult to crystallize, that is, glass with a composition that has a slow crystal growth rate, can be crystallized relatively easily. It is to become like that.

In other words, the crystallization rate is expressed as (crystallization rate) - (number of crystal nuclei) x (crystal growth rate), and crystal nuclei are likely to occur at the fused interface between glass particles (, In .

The number of fused interfaces is large and wide, and therefore there are many generated nuclei, and even if the crystal growth rate is not high, the crystallization rate is increased as a result.

Another major feature of the present invention is that colorless glass powder and colored glass powder are mixed, and the colored glass powder particles are made coarser than the colorless glass powder particles.

In other words, the coarse grains act to form a mottled pattern.

Similar fine particles for colorless and colored raw materials, for example 200
When mixed as fine particles smaller than mesh and manufactured as crystallized glass, the product exhibits a uniform color and does not have a mottled pattern. This makes the process of separately manufacturing colored and colorless raw materials and mixing the powders of each powder meaningless.

(Example) First, the reason for limiting the essential components will be described. The essential ingredients are
Common in colorless and colored glassy raw materials.

5ift: 45-75% (same below weight percentage) 4
If it is less than 5%, it will be difficult to maintain the shape of the compression molded product during heat treatment, and if it is more than 75%, the viscosity of the glass will increase and the densification of the compression molded product will be slow.

AQ*Ch: 20% or less and 20% or more, the viscosity of the glass becomes high and the densification of the compression molded product becomes slow.

CaO: 5 to 40% If it is less than 5%, crystals such as wollastonite and anorsite will be difficult to precipitate. Moreover, if it exceeds 40%, physical properties such as water resistance and acid resistance will be affected.

2% to 20% of Na20+ If the content is less than 2%, the viscosity of the glass becomes high and the densification of the compression molded product becomes slow. Moreover, if it is 20% or more, it is difficult to maintain the shape of the compression molded product during heat treatment.

The above-mentioned essential components are contained in such a way that the total amount is 85% or more, and the reason for this is to maintain the physical properties of the glass.

Next, a coloring agent (Ca
O, FeO+Fe201, Cr201, NiO% Cu
The reason for setting the content (O%Mn0z, etc.) to 10% or less is that not only is it unnecessary from the perspective of coloring, but also that the content of 10% or more increases the difference in physical properties from the colorless glassy raw material. This is because it becomes bigger.

Next, regarding non-essential components, both colorless and colored glass raw materials include MgO, ZnO, BaO, PbO, 8201, etc.
Since sb2o acts as a clarifying agent, it may be added in an amount of 1% or less during melting.

It is also possible to contain a nucleating agent.

Next, the manufacturing method will be explained in detail.

Colorless and colored glassy raw materials are produced by mixing and melting the raw materials for each of the above components to a predetermined composition, and then quenching and crushing this by a method such as water pulverization to obtain glassy bodies. Use as raw material.

Of course, a material having a limited range of component compositions and already in the form of glass may be used as the raw material, and this may be crushed into small bodies by appropriate means.

The glass bodies obtained in this way are further pulverized using, for example, a ball mill, and at this time, the colorless glassy raw material (hereinafter referred to as colorless raw material) is
The content of fine particles of h or less should be 90% or more, and for colored glassy raw materials (hereinafter referred to as colored raw materials), the content should be 10 to 200%.
Mesh powder or 10-200 mesh
The powder must contain 200 mesh or less fine powder.

The thus obtained colorless and colored raw material powders are mixed in a desired ratio so that fine powder of 200 mesh or less accounts for 50% or more of the mixed powder.

In this way, the reason why 200 mesh or less is limited to 50% or more is that if it is 50% or less, that is, if there are many coarse particles mixed in, it will affect dense compaction and increase the temperature at which the particles are fused and integrated. At the same time, if the particle size and amount of the colored raw material powder, which is made into coarse particles, becomes large, air bubbles will be included inside the product.
The reason for setting the mesh size to 0 mesh or less is that if the coarse particles are 10 mesh or larger, air bubbles are likely to be contained inside the product as described above.
This is because there is a risk of reducing the strength. However, in cases where strength and the presence of bubbles are not a problem, some amount of the coarse particles may be allowed.

Next, the mixed powder is compression-molded into a dense powder body with a true density of 55% or more using a compression molding frame of the desired shape. to ensure that densification occurs at low temperatures;
In order to compression mold the glass powder having the above particle size to a density of 55% or more of the true density, a pressure of 20 kgf/aa or more is appropriate.

In compression molding the powder, it is effective to add a small amount of a binder such as polyvinyl alcohol (P, V, A, etc.) to the powder in advance to facilitate molding.

The green compact obtained in this way has a softening point or higher (actually softening point + 10
The temperature is preferably 0°C or higher. ), heat treatment is performed at a temperature below the temperature at which the crystal growth rate increases.

Through this treatment, each glass powder is fused and integrated and densified, and at the same time, nucleation is progressing at the fused interface between the particles.

Once the compact has been densified, the temperature is further increased to encourage crystal growth and crystallization, but as mentioned above, the mixed colored raw material powder has a different composition compared to the colorless raw material powder. Since the composition contains only 10% or less of a coloring agent, there is no significant difference in the softening point and other properties of the two raw material powders, and the integral densification and crystallization of the powder proceed without any problems during the heat treatment described above.

Figure 2 shows the heat treatment curve of the above green compact, where the area between aa is the integral densification area of the glass particles, the area between bb is the crystallization area, and the area between aa and bb is the crystallization area.
, P, is the softening point, and M, P, is the melting point.

The crystallized glass obtained by the above process has a white base due to crystal precipitation, and the colored parts are distributed in a patchy manner.The colored parts are evenly distributed depending on the degree of mixing of powder. It is possible to make it exhibit a fine speckled pattern or a unevenly distributed lumpy speckled pattern, and it is also possible to adjust the density of the speckled pattern by changing the mixing ratio of colored and colorless raw material powders. It is also possible to create a multicolored mottled pattern by using multiple types of colored raw materials with different colors.

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

The colorless and colored raw materials used in the examples had the compositions shown in the table below. The raw materials containing the respective components were melted at 1500°C, and then poured into water to form colorless and colored raw materials, respectively. Glassy bodies were obtained.

Component composition (w, tχ) of colorless and colored raw materials (however, Fe
(O+Fe20s is a coloring agent) The glass particles were ground using a ball mill to obtain the following powder.

Colorless raw materials are powdered colored raw materials of 200 mesh or less.
(40-200 mesh powder): (200
(powder below mesh) = Powder containing at a ratio of 11 The above side powder is mixed at a ratio of 1:l, and P is added as a binder to this.
, V, and A were added in an amount of 5 w and t %, and a compression molded body of 100 x 100 x 25 (mm) was obtained using a compression molding frame. The press pressure during molding is 30kgf/
- and 300 kgf/cflI, but no difference was observed in the physical properties of the heat-treated products.

The above compression molded body was heat-treated by raising the temperature to 690°C at a heating rate of 150°C/hr, maintaining the same temperature for 30 minutes to fuse and integrate the glass powder, and then increasing the temperature to 800°C. When the product was kept at the same temperature for 30 minutes to achieve crystallization, it was observed that wollastonite (CaO 5if2) crystals had precipitated on the product.

Figure 3 shows the heat treatment curve of the above heat treatment, and the physical property values of the crystallized glass obtained by the same treatment have a density of 2.5 g/c.
j, water absorption rate 0.02%, bending strength 710 kgf/d
Met. Note that Figures 4 and 5 are photographs of the crystallized glass obtained in the above example, and Figure 4 shows the case where the raw glass powder was mixed uniformly, with a fine speckled pattern in which the colored parts were finely and uniformly distributed. Figure 5 shows a case where the mixture is unevenly mixed, and the colored area has a lumpy and mottled pattern.

(Effects of the Invention) As described above, the method of the present invention heat-treats a fine powder of a glassy raw material as a compression molded body, thereby eliminating the problem of increased viscosity due to crystal growth unlike in the accumulation method.
Glasses with a wide range of compositions (the composition range specified in the present invention is wide, and many conventional glasses fall within this range) can be easily crystallized, and coloring can be achieved by mixing colored glass powder and colorless glass powder. Because it is heat-treated as a compact, it is possible to create a mottled pattern, and changes in the same pattern also depend on the color, particle size, amount, degree of mixing, etc. of the colored glass particles, as well as the degree of crystallization, etc. It can also be changed in various ways. In addition, since it is molded as a powder compact, it can be easily formed into a desired shape, and it is also easy to form irregularities on the surface.

Furthermore, the fact that it can be manufactured without containing large bubbles inside the product is a great advantage as a material, making the strength of crystallized glass even more reliable.

The industrial value of the present invention, which has various advantages as described above and makes it possible to provide colored patterned crystallized glass as an excellent decorative material and building material, is enormous.

[Brief explanation of drawings]

Figure 1 is a graph conceptually showing the relationship between temperature, nucleation rate, and crystal growth rate when heating a compacted glass powder.The broken line graph is the ``nucleation rate-temperature'' curve, and the solid line graph is [Crystal growth rate vs. temperature] curve. FIG. 2 is a heat treatment curve showing the heat treatment mode in the present invention,
FIG. 3 shows a heat treatment curve of an example of the present invention. Figures 4 and 5 are photographs of crystallized glass of examples of the present invention. Figure 4 is the crystallized glass obtained when the raw material glass powders were mixed uniformly, and Figure 5 is the crystallized glass obtained when the raw material glass powders were mixed uniformly. This is the crystallized glass obtained in this case. Patent Applicant: Kubota Iron Works Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4 Amendment to Figure 5 ("ji*") May 30, 1985 Patent Application No. 2693 2, Name of the invention: Method for producing crystallized glass with colored patterns 3, Relationship with the case of the person making the amendment Patent applicant (105) Kubota Tekko Co., Ltd. 4, Agent 8577 1013 Mikuriya, Higashiosaka City, Osaka Prefecture 06 (782) No. 6917/6918 Showa 61
March 25, 2016 6, Subject of amendment/detailed explanation of the invention in the specification column No. 7, Contents of amendment (1) "Photograph" on page 16, line 17 of the specification tube replaces "pattern composition diagram" ” he corrected. (2) The word “photo” on page 18, line 14 of the same book means,
Corrected to ``Diagram showing pattern composition.'' (3) Figures 4 and 5 attached to the application should be amended as shown in the attached sheet. Figure 4 Figure 5

Claims (1)

[Claims] (1) SiO_2:45 as an essential component in weight percentage
~75%, Al_2O_3: 20% or less, CaO: 5~
40%, Na_2O+K_2O: 2-20%, SiO
_2+Al_2O_3+CaO+Na_2O+K_2O
>85% of the glass-like raw material is pulverized so that particles of 200 mesh or less account for 90% or more, and each component in the above composition range and the weight percentage of 10% or less When mixing a powder containing particles of 10 to 200 mesh or smaller than 10 to 200 mesh by pulverizing a colored glassy raw material containing a colorant, 200
Mix the two in a desired ratio within a range in which particles of mesh size or smaller account for 50% or more, and then compression mold the mixture into a green compact with a true density of 55% or more using a compression molding frame of a desired shape. A color pattern characterized in that the glass powders of the green compact are softened and fused to each other by heat treatment to become integrated and densified, while also crystallizing them to precipitate mainly wollastonite crystals. A method for producing crystallized glass.