JPH07165464A - Production of low-temperature baked ceramic - Google Patents

Abstract

PURPOSE:To provide a method for producing baked ceramics, capable of baking ceramics at a low temperature and utilizing industrial waste as a filler without hindrance. CONSTITUTION:A binder producing aluminum metaphosphate after baking is mixed with a filter and the mixture is formed and this formed material is baked at a low temperature of 600-900 deg.C. Chemical resistance of baked articles can be improved when a binder producing aluminum metaphosphate A type after baking is utilized as the binder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing low temperature fired ceramics.

[0002]

2. Description of the Related Art Firing ceramics are usually obtained by mixing and molding a filler and a binder and then firing. Here, natural raw materials (porcelain stone, feldspar, silica stone, clay, etc.), industrial waste (coal ash, blast furnace slag, sewer incineration ash, etc.) and chamotte are used as fillers, and glass components as binders. Is used.

[0003]

In the conventional method for producing fired ceramics, a glass component is used as a binder, and the liquid phase or solid phase reaction of the binder is used for sintering. However, there is a problem that the firing temperature is required to be 1100 ° C. or higher, and the firing cost becomes high. Also, when using industrial waste other than natural raw materials as filler,
Those having a low melting temperature have a problem that they cannot be used in combination with natural raw materials because they cause foaming, color development and the like.

[0004]

The method for producing low-temperature fired ceramics of the present invention comprises mixing a binder which forms aluminum metaphosphate after firing and a filler, and molding the molded product at 600 ° C to 900 ° C. It is characterized by firing at a temperature. Further, as the binder, it is preferable to use a binder that forms aluminum metaphosphate A type after firing.

[0005]

In the present invention, a binder which forms aluminum metaphosphate after firing is used, and aluminum metaphosphate is produced by firing at a temperature of 600 ° C to 900 ° C and plays a role of a binding medium. . Therefore, by firing the molded product at a temperature of 600 ° C. to 900 ° C., it is possible to obtain a fired ceramic that is sufficiently bonded by the binder. Further, when the binder that produces aluminum metaphosphate A type after firing is used,
Chemical resistance is given to the fired ceramics.

[0006]

EXAMPLES Examples of the present invention will be described below. (Example 1) In this example, the following materials were prepared as a filler and a binder. Filler chamotte (previously that aligns the particle size) first aluminum phosphate binder _{(Al (H 2 PO 4)} 3) 2~60wt the first aluminum phosphate to the chamotte
% And mixed, and this mixture was molded into a predetermined shape by a uniaxial press or an extruder. 6 this molded product in an electric furnace
Firing was performed at 00 ° C to 900 ° C to obtain a fired ceramic. In the fired ceramic thus obtained, the first aluminum phosphate produced aluminum metaphosphate (Al (PO ₃ ) ₃ ) by the above heating, and the aluminum metaphosphate covered the surface of the chamotte to bond it. It will be. The relationship between the firing temperature (° C.) and the bending strength (Kgf / cm ² ) of the above-mentioned fired ceramic is shown in FIGS. 1 to 3 in relation to the change in the content percentage of chamotte. 1 to 3 show the case of using a rough chamotte as a chamotte, a case of using a fine chamotte, and a case of using a coarse and fine mixed chamotte. In each case, sufficient bending strength (tile and The same level) was obtained.

(Example 2) In this example, the following materials were prepared as a filler and a binder. Filler Chamotte (pre-sized particles) Binder A mixture of aluminum hydroxide (Al (OH) ₃ ) and phosphoric acid (H ₃ PO ₄ ) where the above binder is given as a starting material in the actual molding process. The starting material was prepared by weighing aluminum hydroxide and phosphoric acid in a molar ratio of 1: 5, mixing them while heating in a beaker, and melting the aluminum hydroxide to form a transparent liquid. 2 to 60 wt% of the starting material is added to and mixed with the chamotte, the mixture is molded into a predetermined shape in the same manner as in Example 1, and the molded product is fired at 600 ° C. to 900 ° C. in an electric furnace and bonded. Form aluminum metaphosphate type A from the agent to bind chamotte,
A fired ceramic was obtained. The fired ceramics obtained as described above had sufficient bending strength as the fired ceramics of the first embodiment. Moreover, since the aluminum metaphosphate A type is produced in the second embodiment, due to the property that the aluminum metaphosphate A type is not attacked by acid and alkali (compared with aluminum metaphosphate type B), The fired ceramic was endowed with chemical resistance.

As described above, in the first and second embodiments, the ceramics can be fired at 600 to 900 ° C., so that the firing cost is reduced. Further, in any of the first and second embodiments described above, when industrial waste is used instead of chamotte as the filler, or when chamotte and industrial waste are used in combination, the heating temperature of the industrial waste is lowered. Therefore, it is possible to prevent the foaming, the color development and the like.
For this reason, since industrial waste can be used as a filler without any trouble, the raw material cost is reduced, and in that case, the effect of facilitating the surface coloring with the glaze is provided. Note that the binder material that produces aluminum metaphosphate after firing is not limited to those listed in the above examples, for example, alumina (Al ₂ O ₃ ), aluminum hydroxide and a mixture of metal aluminum and phosphoric acid, It can be anything. Further, in the above-mentioned examples, the moldability can be improved by adding plastic clay in addition to the filler and the binder.

[0009]

According to the present invention, since a binder that forms aluminum metaphosphate after firing is used, ceramics can be fired at a low temperature of 600 ° C to 900 ° C, and the firing cost can be reduced. Further, even when industrial waste is used as a filler, the heating temperature is lower than the temperature at which foaming, coloration, etc. do not occur, so the raw material cost is reduced, and in that case, the effect of facilitating surface coloring with glaze Have. Further, when a binder which forms aluminum metaphosphate A type after firing is used as the binder, the fired ceramics have chemical resistance, so that the quality of the fired ceramics is improved.

[Brief description of drawings]

FIG. 1 shows the relationship between the firing temperature (° C.) and the bending strength (Kgf / cm ² ) of a fired ceramic obtained by the method of the first embodiment of the present invention, using the crude chamotte. The graph figure shown in relation to change.

FIG. 2 is a graph similar to FIG. 1 when a thin chamotte is used as the chamotte.

FIG. 3 is a graph similar to FIG. 1 when a coarse-fine mixed chamotte is used as chamotte.

Claims (2)

[Claims] 1. A method for producing low-temperature fired ceramics, which comprises mixing and molding a binder that forms aluminum metaphosphate after firing and a filler, and then firing the molded product at a temperature of 600 ° C. to 900 ° C. . 2. The method for producing a low temperature fired ceramics according to claim 1, wherein a binder which forms aluminum metaphosphate A type after firing is used as the binder.