JPS60204681A - Manufacture of lightweight ceramic construction material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing ceramic building materials that are lightweight and can withstand frost damage even in cold regions.

In recent years, lightweight and strong steel frames and reinforcing bars have increasingly been used for construction, and along with this, other construction materials have also been required to be lightweight. Architectural ceramic products are no exception. In response to this demand, lightweight ceramic construction materials have been provided in the past. For example, the one described in Japanese Patent Application Laid-open No. 49-42707 is one such example.

The method described in this publication is made by adding self-hardening aged sand to a base material such as feldspar or steel slag, and adding a blowing agent selected from silicon carbide and silicon nitride and a softening agent such as carbonate. It is obtained by heating and combusting a mixed material, and its specific gravity is in the range of about 0.5 to 1° Og/-. However, it is still difficult to say that the weight is sufficiently reduced. In addition, conventional lightweight ceramic building materials inevitably have to be made porous as well as lightweight, which makes it impossible to avoid an increase in water absorption. When such lightweight ceramic building materials are used in cold regions, there is a great risk of frost damage.

In view of the above-mentioned drawbacks of the conventional art, the present invention improves and eliminates these drawbacks.
．． Add and thoroughly mix 0.05 to 0.30 parts by weight of SiC powder of less than 0.00 g and an appropriate amount of powdery binder necessary for bonding the powdery material, and mold the mixed material into a predetermined shape. The present invention aims to provide a method for manufacturing a ceramic construction material that is lightweight, has excellent heat insulation properties, and has excellent frost damage resistance, by foaming and firing the base body obtained by the molding at a temperature of 1150 to 1250°C. It is something.

The three materials used in the manufacturing method of the present invention are fine-grained natural glass, SiC19 body, and binder.

First, the characteristics of these materials, their addition amounts, and necessity will be explained.

The fine-grained natural glass is a base material constituting the lightweight ceramic building material (hereinafter simply referred to as the main building material) according to the present invention, and materials such as what is commonly called Ise silica sand, anti-firestone, etc. are used.

SiC powder (purity of 99% or more) causes the foaming phenomenon when firing the present building U, and is the most important additive in the method of the present invention. Those having a particle size of 10 μm or less are used. If the diameter exceeds 10 μm, not only will it be difficult to obtain a homogeneously dispersed mixed state, but also coarse air bubbles will be formed in the substrate during the foaming phenomenon during firing, and in some cases, these bubbles may damage the skin layer of the substrate. Since it will break and be released to the outside, there is a risk of increasing the bulk specific gravity and water absorption rate of the building material. An increase in bulk specific gravity leads to an increase in the weight of the building material, and an increase in water absorption rate deteriorates frost resistance. The amount of SiC powder added is 0.05 to 0.
．． The range is 30 parts by weight. If the amount added is less than 0.05 part by weight, the foaming phenomenon during firing will be inactive, resulting in a high bulk specific gravity, making it impossible to obtain the desired lightweight heat insulation benefit. Also, if the amount added exceeds 0.30 parts by weight, the foaming phenomenon will be too active.
During firing, the skin layer of the base material is broken and air bubbles are dissipated, which also tends to increase the bulk specific gravity. Moreover, when the air bubbles dissipate, pores are formed in the epidermal layer, increasing the water absorption rate. Moreover, it is difficult to maintain the smoothness of the surface layer (which is not preferable).

In short, the preferable amount of SiC powder to be added is required to be within a range where bubbles do not appear to the surface layer during firing and bubbling is sufficiently active to the extent that fine and uniform bubbles are obtained.

The binder is used to bind fine natural glass or SiC powder, which is a base material, and shape the base body.

This binder is an essential element in obtaining a green body since natural glass does not have plasticity. For this reason, it is desirable to have a material that has strong caking properties and burns out at low temperatures during firing. Such materials include polyvinyl alcohol (PVA), acrylic resins, and wax emulsion binders. The amount added is preferably 20 parts by weight or less. The reason is that if it exceeds 20 parts by weight,
Foamability decreases and pore uniformity deteriorates. Furthermore, there are drawbacks such as a decrease in moldability during molding.

In the present invention, the above-mentioned materials are treated as described below to obtain lightweight ceramic building materials.

That is, first, fine-grained natural glass and SiC powder are mixed and polished using a dry or wet mixer to adjust the clay.

The particle size of the mixed clay may be 100 mesh pass (149 μm or less), but preferably 325 mesh pass (149 μm or less).
44 μm or less). This is because finer particles are more foamable.

Then, a binder is added to the obtained mixed clay and kneaded,
Adjust the moisture content so that it is suitable for dry or wet molding.

Next, the thus obtained mixed material is formed into an arbitrary shape by dry or wet forming to obtain a base body.

After that, the base body is dried and fired,
Obtain the desired ceramic-based lightweight heat-insulating building material. This firing process is necessary to internally foam the body, expand its volume to a desired size, and solidify it. The firing temperature was in the range of 1150 to 1250°C. If the natural glass particles used as the base material are fired at a temperature below 1150°C, sufficient melt viscosity will not be obtained, and the foaming phenomenon of the base material will not occur, or even if it does occur, the foaming phenomenon will be inactive. Building materials are not available. Also, when fired at 1250℃ or higher,
The foaming phenomenon is too active and the bubbles become coarse and uneven.

Bubbles appear in the surface layer, making it impossible to obtain a smooth surface. Moreover, rainwater and the like easily penetrate through the air bubbles that appear in the surface layer, resulting in a high water absorption rate and a lack of frost damage resistance. Furthermore, when firing at 1250° C. or higher, it becomes difficult to maintain the shape of natural glass with low fire resistance, making it impossible to obtain a building material with a desired shape. As described above, it is important that the firing temperature is within the above-mentioned range, but this varies depending on the particle size and amount of SiC powder used as the type 1 foaming material of the natural glass used. In addition, the firing schedule, such as heating rate and time, firing temperature and time, has a great influence on foaming properties and must be carefully determined.

Next, an example of a specific manufacturing method according to the method of the present invention will be described.

First, 100 parts by weight of Ise silica sand, which is fine-grained natural glass, is prepared, and SiC powder (99% purity) as a foaming material is added to this.
above) were added. This is then dry mixed and crushed, and a 3% aqueous solution of polyvinyl alcohol as a binder is added to the mixed clay obtained in this way at a ratio of 15% to natural glass.
Part by weight was added. This was then kneaded to adjust the moisture content. Next, the mixture thus obtained is dry-molded. The molding was done using a square concave lower mold with a side size of 100.
The mixture was filled with the dry mixed material and compressed using a hydraulic press to obtain a substrate having a thickness of 8 mm. The pressurizing force in this case was 250 kg -f /c+a, and the pressurizing time was 10 seconds.

After that, the above-mentioned green body was dried and then fired. The firing process was performed using a tunnel-shaped heating furnace over a period of 25 to 35 hours. The thus obtained building material had a square plane with a side of 150 squares and a thickness of 13 mm.

In other words, the base body expands linearly by approximately 1
．． This shows a five-fold increase.

The following Table 1 shows various properties of the present building material produced in the manner described above, when the amount of SiC powder added, the particle size, and the firing temperature are varied.

(The following margins continue on page 9) As shown in Table 1, the bulk density of all examples is below 0.5 g/cffl, which has never been experienced before, and is excellent in weight reduction. is clear.

In addition, in terms of water absorption, all of the examples showed a value of 0.5% or less, and were sufficiently resistant to frost damage in cold regions. Note that this water absorption range is within the range of porcelain.

As explained above, in the present invention, a substrate formed from fine-grained natural glass with an appropriate amount of fine SiC powder added is fired at an appropriate temperature to uniformly encapsulate a large amount of fine air bubbles. The resulting building material not only achieved a weight reduction that had never been experienced before, but also had an extremely low water absorption rate, making it suitable for use in Jianqin in cold regions. We were able to obtain the following frost damage resistance results.

Patent Applicant: Ina Seito Co., Ltd., Ryuji Tenchi, Rihito, Patent Attorney: Toshihiko Uchida, Commissioner of the Patent Office, March 29, 1985, 2. Title of the Invention: Method for Manufacturing Lightweight Ceramic Building Materials 3. Relationship with the Amendment Person Case Patent applicant location: 3-6 Koie Honmachi, Tokoname City, Aichi Prefecture Name (0
47) Representative of Ina Seito Co., Ltd. Representative Director Teruzo Ina (1 other person) 4 Agents 1-2-2-1200, Umeda, Kita-ku, Osaka 6 Contents of amendment (1) “Scope of Claims” column Corrections shall be made as per the attached sheet.

(2) Amendment to the “Detailed Description of the Invention” column ■ On page 2, line 6 of the specification, "Heating combustion" It is stated that "Heating and firing" and correct it.

■ On page 2, line 10 of the specification, “Lightweight ceramic construction material” It is stated that “Lightweight ceramic construction materials” and correct it.

■ On page 2, line 18 of the specification, "Powdered binder" It is stated that "Binding agent" and correct it.

■Page 3, line 5 of the specification, "Binding material" It is stated that "Binding agent" and correct it.

■ On page 4, lines 14 to 15 of the specification, it is stated that ``sufficient bubbling is carried out to the extent that fine and uniform bubbles are obtained''. is dispersed uniformly, and the foaming phenomenon takes place sufficiently actively.''

■ On page 6, line 6 of the specification, the statement ``Objective light-weight ceramic-based heat-insulating building material'' has been amended to ``Objective light-weight and highly heat-insulating ceramic building material.'' .

■ On page 7, line 15 of the specification, "Binding material" It is stated that "Binding agent" and correct it.

7. A document stating the entire text of the scope of claims after the amendment to the list of attached documents (attached sheet) 1 document 1 stating the entire text of the scope of claims after the amendment, fine-grained natural glass 1oo. Add 0.05 to 0.30 parts by weight of SIC powder of 1 μm or less and an appropriate mixing agent necessary for binding the powder and granules, mix thoroughly, and mold the mixed material into a predetermined shape. A method for manufacturing a lightweight ceramic construction material, which comprises foaming and firing the base body obtained by the molding at a temperature of 1150 to 1250'C.

Claims (1)

[Claims] 1. To 100 parts by weight of fine-grained natural glass, add 0.05 to 0.30 parts by weight of SiC powder with a particle size of 10 μm or less and an appropriate amount of powder-like binder necessary for bonding the powder-like materials. A method for manufacturing a lightweight ceramic construction material, which comprises mixing the mixed materials, molding the mixed material into a predetermined shape, and foaming and firing the base body obtained by the molding at a temperature of 1150 to 1250°C.