JPH11292613A - Production of ceramic sintered product having function for activating water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a sintered product having a function for activating water by carrying out the sintering treatment of a process for producing the ceramic having the function for activating the water, capable of preventing the fusion of the ceramic molded product and the generation of defective products and clearly improving effects for inhibiting the generation of rust and microorganisms. SOLUTION: This method for producing a ceramic sintered product having a function for activating water comprises crushing natural rocks containing silica, alumina, sodium oxide, potassium oxide, magnesium oxide, calcium oxide and iron oxide as components, filling an alumina vessel, etc., with the obtained spherical crushed products, sintering the filled spherical products under vacuum in a vacuum oven or in a hydrogen atmosphere and subsequently naturally cooling the sintered product. Since the removal of oxygen atoms from the surfaces of the sintered products is thereby accelerated, a treating temperature can be lowered, and the obtained ceramic can be kept away from its melting. Double effects that the effect is increased at the same sintering temperature can be expected, since the local release of oxygen atoms is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a ceramic sintered body having a function of activating water.

[0002]

2. Description of the Related Art Among the conventional functional ceramics, the action mechanism of a silica-alumina-based ceramic sintered body, which is known to be effective in suppressing the generation and growth of red rust and microorganisms in water, is known. There is no clear knowledge, but only the empirical fact that simply sintering at a high temperature increases its effect has been revealed. However, due to the high-temperature treatment, the melting of the granular or spherical ceramic molded body starts, and even if only the surface is melted, mutual fusion occurs, and the tendency to form a large lump and lose the form of the product becomes stronger. In addition, the starting material for this ceramic is natural rock, and its chemical composition varies from region to region, so its melting temperature also varies considerably, quality control is not easy, and frequent fusing phenomena significantly impair product yield. In order to stabilize, a troublesome sintering test for each raw material lot was required in advance.

[0003]

This product makes use of natural substances that exist in a wide range and almost infinitely, and can be manufactured without using any aggressive chemicals.
In addition to being based on the principle of pollution-free and resource saving, the application is also in such a broad and earth-friendly area as described above. Since the potential given by nature has been discovered, controlling it with a new way of thinking is one of the important missions of modern natural science. Tried to solve the point. To this end, it is a matter of priority to clarify the mechanism of action that underlies the effect.

The present invention relates to a process for sintering a ceramic sintered body in which the effect of high-temperature treatment has been found to be improved. The primary purpose of the present invention is to fundamentally improve the current situation in which the cost of factories must be increased and to eliminate the occurrence of fusion. Achieving this goal is difficult because its mechanism of action is unclear.
The inventors of the present invention have been able to clarify this through many years of research, and by using this as the axis, it has become possible to further achieve the second object, that is, improvement of the effect.

[0005]

Means for Solving the Problems In order to achieve the above object, as a production method of the present invention, a step of sintering a ceramic molded body is performed by a conventional method of sintering in air under atmospheric pressure. Instead, it was performed under reduced pressure or in a hydrogen atmosphere.

[0006] This idea is based on the mechanism of the effect of the high-temperature treatment, which is a conventional finding, based on the formation of a “non-stoichiometric composition structure” on the surface by local escape of oxygen atoms from the surface of the ceramic sintered body. It is based on the recognition as an essential "source of water activating function" derived from the generation of lattice defects. If this is the case, the process temperature can be lowered, because decompression (removal of oxygen in the atmosphere) or the presence of hydrogen will promote escape,
It is possible not only to keep the ceramics away from the danger of melting, but also to expect the double effect that the effect is improved even at the same sintering temperature by increasing the local escape of oxygen atoms. it can. Red rust (Fe ₂ O
₃ ) The suppression of generation and increase is due to the fact that this lattice defect acts as an electrophilic-reducing function, and black rust (Fe ₃ O ₄ ), which has fewer oxygen atoms than red rust, per iron atom, is converted to iron It is presumed to be due to generation as a passivation of the surface. In addition, it is considered that the suppression of the generation and growth of microorganisms may be caused by the relative oxygen deficiency caused by this reducing action.
This will be demonstrated below with reference to examples using these techniques.

[0007]

Example 1 59% silica, 28% alumina, 2.5% sodium oxide, 2.6% potassium oxide, 2.0% magnesium oxide, 1.8% calcium oxide, 3.8% iron oxide
% And other natural ingredients are crushed to a diameter of 3-4.
mm was spheroidized into a vacuum furnace using an alumina container, and the average heating rate was 6 to 7 ° C. per minute and the degree of decompression was 10
After heating to each temperature shown in Table 1 below at ３０30 Torr, holding at the same temperature for 2 hours, sintering, and then naturally cooling.
For comparison, sintering was carried out at atmospheric pressure without changing the pressure and under the same conditions as above.

[0008] In order to evaluate the obtained sintered body, 500c
c. 45 g of each of these sintered spheres was placed in a beaker.
0cc. 20x20x0.5mm with tap water
A piece of pure iron (stored in ethanol) of the following size is placed on each sphere and kept at 30 ± 5 ° C. for 360 hours, always in parallel with tap water only (no sintered spheres), every 24 hours Was removed and subjected to ultrasonic cleaning in ethanol to remove generated rust, and then its weight was measured in ethanol.

As a result, red rust is observed on both sides of the iron piece only when the ceramic sintered sphere does not exist. When the effect of the sintered sphere is small, red rust is easily removed. Since red rust which is easy to occur occurs and increases at the same time, the increase in red rust (relative performance) can be quantitatively compared as a clear weight loss rate.

Table 1 summarizes the results. this

In Table 1, the increase in weight means that the generation of red rust, which is easily peeled off due to the generation of black rust and the adhesion to the iron piece surface, was very small.

[0010]

[Table 1]

From these results, it can be seen that sintering in a hydrogen atmosphere has prevented fusion at a high temperature and significantly improved the effect of preventing red rust from increasing.

Next, the effect of preventing the growth of microorganisms using the same sintered spheres as above was compared. 500cc. Into a beaker, 30 g of each of the sintered ceramic spheres shown in Table 1 and tap water were put, and the whole was 500 cc. 25
It was kept in a constant temperature water bath maintained at ± 0.5 ° C. and continued for 50 days while supplying tap water. As a result, when the state of the algae on the 50th day was visually observed, 7 (tap water)> 5 ≒ 6> 2 ≒ 3> 1 in the descending order of the algae using the experiment numbers shown in Table 1, and in the case of 1, When the sintered spheres were brought into contact with each other and did not coexist with the spheres, the number of algae was even less than that of the above-mentioned 1.

[0013]

Embodiment 2

The ceramic formed into a spherical shape before sintering described in Example 1 was replaced with a hydrogen atmosphere furnace instead of a vacuum furnace, and the other heat treatment conditions were completely maintained while holding the ceramic sintered body in a hydrogen stream. Sintering was performed in the same manner. Regarding the red rust increase suppression test and algae growth suppression test of the obtained sintered body,

Performed in the same manner as in Example 1,

Table 2 shows the results. this

In Table 2, Experiment Nos. 11 to 14

Table 1 shows the results of a comparative experiment under the same conditions as those in Examples 4 to 7 above.

Since the experiment was conducted at a different time from Table 1, the comparison was again made.

[0014]

[Table 2]

The result is

Compared to Table 1, it can be seen that sintering under reduced pressure clearly has a greater effect of suppressing red rust than sintering in air. However, the magnitude of the effect depends on the decompression method (

It was also found to be inferior to Table 1). Experiment number 4
As in Nos. 7 to 11, 11 to 14 are under the same conditions at different experimental times, but are considered to be highly reproducible as this kind of long-term test method.

Next,

The same algal growth test as in Example 1 was carried out on this reduced pressure sintered body.

At a different time from Table 1,

The comparison was carried out in the same manner as in Table 2.

[Table 1],

This is a test method that is difficult to quantify as shown in Table 2.

Although the exact comparison with Example 1 was difficult as a result,

In the order of the growth inhibitory effect as shown in Example 1, exactly the same qualitative results were obtained as follows.

That is, when the state of the algae on the 52nd day was visually observed, the order of tap water> 12 ≒ 13> 9 ≒ 10> 8 in the descending order of the algae.

By performing the sintering under reduced pressure or in a hydrogen atmosphere in this way, the fusion of the ceramic molded body—the generation of defective products—is prevented, and at the same time, the generation of red rust, the generation of microorganisms, and the increase of the rust are prevented. It was confirmed that the suppression effect was clearly improved.

Claims (2)

[Claims] 1. A method for activating water by performing a sintering step for producing a “non-metallic material obtained through steps such as molding and firing” (hereinafter abbreviated as “ceramics”) under reduced pressure. A method of manufacturing a ceramic sintered body having the function of performing 2. A method for producing a ceramic sintered body having a function of activating water by performing a sintering step for producing ceramics in a hydrogen atmosphere.