JPS63201072A - Manufacture of ceramic foam - 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 [Industrial Field of Application] This invention relates to a method for manufacturing ceramic foam. More specifically, the present invention relates to a method for manufacturing a ceramic foam having a glazed skin layer on its surface.

[Conventional technology]

For example, ceramic foam is disclosed in Japanese Patent Application Laid-Open No. 60-221371.
As described in the publication, it is manufactured by heating a ceramic foaming composition made by mixing powders such as volcanic ash or glass with a foaming agent to a foaming temperature. This ceramic foam is attracting attention as a suitable building material because it is lightweight and highly durable.

When using ceramic foam as a building material,
It is generally desirable to apply a glaze to the surface of the ceramic foam to improve its appearance and further improve its durability.

The conventional method of applying glaze to ceramic foam is to first cool the ceramic foam produced by heating and foaming, then apply glaze to the surface, heat it again, and bake the glaze onto the ceramic foam. It has been known.

[Problem that the invention seeks to solve]

However, in the above method, heating for foaming and heating for baking the glaze are performed in two stages, which not only causes large fuel losses and is uneconomical, but also complicates the manufacturing process. there were.

[Means for solving problems]

This invention was made to solve the above problem.
The gist is that after placing the granulated glazes on the granulated ceramic foaming composition, it is heated to the foaming temperature to foam the ceramic foaming composition to form a ceramic foam, and the glazes are baked. , and then cooling.

[Effect]

When the granulated ceramic foamable composition is heated and foamed, a good ceramic foam with uniform cell diameters can be obtained.

Therefore, the glazes on the ceramic foamable composition are also melted to form a uniform skin layer. Furthermore, the granulated glazes have good compatibility with the ceramic foamable composition and form an excellent skin layer when melted.

The ceramic foamable composition used in this invention mainly contains volcanic rock such as anti-firestone, volcanic ash such as whitebait, feldspar, clay, glass powder, etc., and if necessary, foaming temperature controlled material such as soda ash. It is a ceramic composition that has the property of foaming when heated, to which a foaming agent such as silicon carbide is added.

In the present invention, this ceramic foamable composition is used in the form of granules. As the granulation method, various granulation methods can be used, such as a roll granulation method, an extrusion type granulation method, and a rotating disk type granulation method.

The reason for using granules is that if a ceramic foamable composition in the form of powder other than granules is used, the surface of the ceramic foam after foaming will become uneven, making it difficult to obtain a good foam.

There is no particular limit to the size of the granules, but if the diameter is 0.5
Preferably, the period of time is between 2 and 3 days.

The glazes used in this invention are those commonly used for ceramics, roof tiles, enamel, etc., but in particular, in this invention, glazes that soften and melt at a temperature below the foaming temperature of the ceramic foam composition are used. In addition to the above-mentioned glazes, the glazes of the present invention may also include inorganic materials such as volcanic rock and volcanic ash that melt at a temperature below the foaming temperature of the ceramic foaming composition, or materials to which pigments are added. It includes all substances that act in the same way as glazes. For example, a ceramic foamable composition with the foaming agent removed, a composition with the addition of something that lowers the softening temperature, such as soda carbonate or silt, and a composition with a pigment added thereto, can be used. It is particularly preferable that the softening temperature of the glaze is 100°C to 300°C lower than the foaming temperature of the ceramic foamable composition. Preferably, the glazes used in the present invention have a volumetric expansion coefficient substantially the same as that of the ceramic foam, and preferably have a volumetric expansion coefficient of 130X10-' to 250X10-'.

In this invention, glazes are used in the form of granules. The reason why granules are used is that if glazes are used in powder form, cracks are likely to occur when the glazes are melted and baked.

As for the granulation method of the glazes, the same method as for the ceramic foamable composition can be used. At this time, it is preferable to add a small amount of clay such as bentonite, frog's eye clay, or clay, for example, 1 to 10%, to facilitate granulation.

There is no particular limit to the size of granules of glazes, but if the diameter is 0.
．． 2 mm to 2 cranes are suitable.

Next, embodiments will be described with reference to the drawings.

In the figure, 1 is a ceramic foam manufacturing apparatus. This ceramic foam manufacturing apparatus 1 has a conveyor 2.

The conveyor 2 is made of a fine mesh body made of heat-resistant metal such as stainless steel. When the conveyor 2 travels on the lower side, a mold release agent 4 is applied to the surface by a coating device 3. As the mold release agent 4, aluminum oxide powder, aluminum hydroxide powder, silica sand powder, calcium carbonate powder, clay powder, etc. are used.

A main raw material hopper 5 and a glaze hopper 7 are arranged above the conveyor 2, and a granulated ceramic foam composition 6 is dropped from the hopper 5, and a granulated glaze 8 is sequentially dropped from the hopper 7. , are each supplied onto the conveyor 2 to a substantially uniform thickness.

Furthermore, if necessary, a template coated with a mold release agent can be placed on top of this. Alternatively, a release paper may be placed, a template may be placed on top of the release paper, and pressure may be applied.

Next, the conveyor 2 is sequentially moved to a preheating furnace 9, a heating furnace 10, and a slow cooling furnace 1.
It is designed to pass through 1.

While passing through the heating furnace 10, the ceramic foamable composition 6 is heated to the foaming temperature. Then, the glaze 8 softens and melts, and the ceramic foamable composition 6 softens, melts, and foams, forming a ceramic foam having a layer of glaze on its surface.

Next, it enters an annealing furnace 11 and is slowly cooled, and then exits from the furnace.

The granulated ceramic foamable composition 6 becomes a better ceramic foam with uniform cell diameters when foamed, compared to one that is not granulated.

When glazes are melt-baked, cracks may occur in the layer, but in this invention, since the glazes are granulated, cracks are prevented from occurring, and the granulated ceramic foam composition In addition to obtaining a uniform ceramic foam, the glaze is evenly melted and baked, creating a layer of glaze with a beautiful surface.

Moreover, if the template 12 is placed on top at this time, a good product with the pattern of the template 12 will be produced.

〔Effect of the invention〕

In this invention, after the glaze is placed on the ceramic foamable composition, it is heated to the foaming temperature, so that the heating process of foaming the ceramic foamable composition and melting the glaze is done in one step.
It is both simplified and economical. In addition, since a granulated ceramic foam composition and a granulated glaze are used, a good ceramic foam with uniform cell diameter can be obtained, and a uniform and beautiful skin layer can be formed on the surface. Can be done.

The ceramic foam obtained by the present invention can be suitably used as a building material such as an exterior wall material, a floor material, a roof material, or a heat insulating material for a house.

Example 1 A ceramic foamable composition consisting of 58 parts by weight of anti-firestone powder, 25 parts by weight of glass powder, 10 parts by weight of bentonite, 5 parts by weight of soda carbonate powder, 2 parts by weight of oxoxide, and 0.3 parts by weight of silicon carbide powder was uniformly mixed. After adding 15 parts by weight of water and kneading well, granulating using an extrusion type granulator with multiple diameters, drying thoroughly to obtain a granulated product of the ceramic foamable composition. Manufactured.

In addition, white glaze (XT-275 manufactured by Nippon Frit 011)
N, softening temperature 657℃, volumetric expansion coefficient 195X10-'
), 8 parts by weight of bentonite was added to 100 parts by weight, and after thorough mixing, 20 parts by weight of water was added, and the mixture was kneaded using the same extrusion type granulator used to granulate the ceramic foamable composition. After that, it was sufficiently dried to obtain a granulated glaze.

The granulated ceramic foamable composition 6 is transferred to the main raw material hopper 5.
The granulated glaze 8 was put into the glaze hopper 7.

On the conveyor 2, the ceramic foamable composition 6 was uniformly supplied from the main raw material hopper 5 to a thickness of about 3011 mm, and then the glaze 8 was placed on top of it from the glaze hopper 7 to a thickness of about 5 mm. A template 12 made of silicon carbide was placed on top of it. template 12
A mold release agent made by adding a small amount of bentonite to alumina powder to improve adhesion to the mold plate 12 was applied to the surface of the mold plate.

These are led from the preheating furnace 9 to the heating furnace 10, where 970
℃, the glaze 8 was softened and melted, and at the same time, the ceramic foamable composition 6 was softened and melted to foam. At this time, since the surface of the ceramic foam is pressed by the template 12, it assumes the shape of the template 12. After that, the temperature of the ceramic foam is gradually lowered in an annealing furnace 11 until it is cooled to about 100°C, and reaches the outlet.When the template 12 is removed here, a glaze decoration with a pattern made by the template 12 is formed on the surface. A ceramic foam was obtained.

The obtained ceramic foam has a thickness of about 43 mm and a specific gravity of 0.
．． No. 63, it had a beautiful skin layer whose surface was covered with a layer of white glaze.

Example 2 65 parts by weight of whitebait powder, 25 parts by weight of glass powder, 5 parts by weight of bentonite, 5 parts by weight of soda carbonate powder, and 0.3 parts by weight of silicon carbide powder were uniformly mixed, and 15 parts by weight of water was added thereto. The mixture was thoroughly kneaded and granulated using an extrusion type granulator having a large number of holes with a diameter of 1.2 tm, and then thoroughly dried to produce a granular ceramic foam composition.

55 parts by weight of whitebait powder, 25 parts by weight of glass powder, 5 parts by weight of bentonite, 5 parts by weight of soda carbonate powder, 10 parts by weight of urexide powder, and 3 parts by weight of reddish brown pigment (enamel L-96 manufactured by Nichiuchi Sangyo ■) were uniformly added. Mix, add 15 parts by weight of water, knead well, granulate using an extrusion type granulator with many holes of 1.2 m in diameter, and dry thoroughly to form a glaze granule. Manufactured.

Using the ceramic foam manufacturing apparatus 1 used in Example 1, the granulated Ceramisec foamable composition is supplied onto the conveyor 2 to a thickness of about 27 fins, and the granulated glaze is applied thereon to a thickness of about 5 fl. I posted it on.

A ceramic foam was produced by heating and foaming in the same manner as in Example 1 except that a template was not placed.

The resulting ceramic foam has a thickness of approximately 43 mm and a specific gravity of 0.
．． 6 and was beautiful with a reddish-brown glazed surface.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing an example of a ceramic foam manufacturing apparatus used in the present invention. 2... Conveyor, 5... Main raw material hopper, 6...
Ceramic foamable composition, 7... Glaze hopper, 8
... Glazes, 9... Preheating furnace, 10... Heating furnace, 1
1... Annealing furnace, 12... Template.

Claims (1)

[Claims] 1. After placing the granulated glaze on the granulated ceramic foaming composition, heating it to a foaming temperature to foam the ceramic foaming composition to form a ceramic foam. A method for producing a ceramic foam, characterized by baking a glaze and then cooling it. 2. Claim 1, in which the granulated glaze softens and melts below the foaming temperature of the ceramic foamable composition.
A method for producing a ceramic foam as described in Section 1.