JPS60149403A - Manufacture of ceramic fiber molded part - 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 manufacturing a ceramic fiber molded body.

Molded bodies using ceramic fibers were initially used as energy-saving materials, mainly as insulation materials for feeders of non-ferrous metals such as aluminum and aluminum alloys, and as heat-resistant containers such as ladle and dipers. However, recently, it has been widely used due to its properties such as heat insulation, fire resistance, and electrical insulation, and among these wide range of uses, it is especially important to use one of its components, such as combustor equipment such as hot water boilers and bathtubs. It has come to be used as a component.

Therefore, there are cases in which the conventional dimensional accuracy cannot be used as a component, and in particular, when assembling a component, the same dimensional accuracy as the mating material is required.

However, in the case of conventional ceramic fiber molded bodies, the main material of the molded body is fibrous, so depending on the way the fibers are entwined and the type of binder used, the dimensions of the molded body often differ significantly due to shrinkage due to restoration during drying. This has become more and more common, causing inconvenience.

Further, even if an attempt is made to fix the fibers using an inorganic binder, the binder moves with the moisture during drying, resulting in a so-called sandwich phenomenon in which only the surface of the molded product becomes hard. Furthermore, when an organic binder is used, the dimensional accuracy and hardness of the shape are reduced at room temperature, but the
When the temperature exceeds 0°C, the binder burns out and loses its shape. On the other hand, as a molding method for complex shapes, JP-A-53-4013 or JP-A-53-14
816, etc., but the drawbacks are that the dimensions are restored when drying or a large number of molds are required, making mass production impossible.

Therefore, the present invention provides a method for obtaining a molded body using ceramic fibers, which has good dimensional accuracy, has uniform hardness in the thickness direction, can withstand use at high temperatures, and can be mass-produced. That is.

That is, in the present invention, after dispersing ceramic fibers and fine clay minerals in water, at least one type of cationic organic or inorganic flocculant is added to form a floc of ceramic fibers containing clay minerals. cause things to form,
The method is characterized in that the flocs are deposited on the surface of a porous mold connected to a vacuum suction device 1, and a press mold is pressed against the deposited layer of the flocs for pressing. The ceramic fibers used in the present invention are made of, for example, alumina and silica, and are obtained by melting at a temperature of 2000"C or higher and then blowing it away with compressed air. Ceramic fibers, alumina crystalline fibers, and silica fibers , rock wool, etc. Also, fine clay minerals are hydrated alumina silicate,
Those that solidify when heated or when wetted with water and dried are good, such as kaolinite, montmorillonite, and sericite.

Examples of organic flocculants include cationic polyacrylamide, cationized starch, and cationic polyamide resins, and examples of inorganic flocculants include aluminum sulfate, ferric chloride, and polyaluminum chloride.

The feature of the present invention is that by incorporating clay minerals into the ceramic fiber flock, the shape is firmly fixed when press-molded, and the clay minerals solidify when drying.
It has uniform hardness in the thickness direction, suppresses the restoration of ceramic fibers, and can obtain a molded product with good dimensional accuracy.

Furthermore, since this molded body is filled with inorganic clay mineral, it exhibits sufficient fire resistance even at high temperatures.

Next, embodiments of the present invention will be specifically described.

Example 1 Silica alumina m-fiber (product name Ibiwool)? .

12.5 parts by weight of montmorillonite mineral,
10.000 parts by weight of water was sufficiently stirred and mixed using a pulper. Thereafter, 0.5 parts by weight of cationic polyacrylamide (trade name: Sunpoly-) was added to obtain a floc-like material. In these mixed liquids, an outer diameter of 50fi and a length of 30011
A cylindrical mold made of the punching metal No. 5 wrapped with K gold steel was put into the mold, and suction was applied for 20 seconds using a vacuum suction device to obtain a cylindrical molded product with a thickness of approximately 10111 mm. From the circumferential side of the molded body deposited in this mold, ta, s kti/c
Press molded at a pressure of d, with a circular diameter of 50 mm and an outer diameter of 60 f.
i. A cylindrical molded piece of cod with a length of 300 mm was obtained. The moisture content at this time was 95%, and the outer circumference u of this molded product after drying at 105° C. for 2 hours was 60.5 wg.

Moreover, the bulk density of this molded body was 0.501/d.

As a comparative example, in the same manner as in Example 1, vertical l Q
Q fi, a flat mold with a width of 100 g and a thickness of approximately 1
A molded body of 0fi was obtained.

Table 1 shows the blending ratio, moisture content, recovery rate, bending strength, and bulk density.

Table 1 Comparison of physical properties of various formulations Here, the moisture content is determined by the moisture content of the product after press molding using the following formula.

In addition, the restoration recovery rate is determined by the following formula from the thickness when wet and the thickness when dry.

Example 2 913 parts by weight of silica alumina fiber (trade name Ibiwool), 71 parts by weight of kaolinite fine powder, and 100.00 O water
Thoroughly stir and mix the N amount using a pulper.

Thereafter, 13 parts by weight of cationic starch and 3 parts by weight of cationic polyacrylamide were added to obtain a floc-like material. 1,500 vertically and 200 horizontally in these mixed liquids.
A rectangular cylindrical mold made of silk punching metal with a height of 200 mm and a wire mesh wrapped around the surface was put in, and a vacuum suction device was used to mold it.
Suction was carried out for 30 seconds to obtain a rectangular cylinder with a thickness of approximately 15 m. Okv'd from the four sides of the molded body deposited in this mold, 5
．． 6 kn/cd, 11.0 kv'd, 13.8
&f/d, press molding was performed at a pressure of 27.5 kg/d to obtain a molded body tube having the physical properties shown in Table 2.

Table 2: Physical Properties of Molded Body by Press Molding As mentioned above, according to the present invention, the restoration recovery rate of the conventional molded body is 1/10.
The following results, and it is possible to obtain a molded body according to the preset mold. Furthermore, as is clear from the comparison with the comparative example, a molded product with high strength can be obtained, which has the advantage of being easy to handle, and as is clear from Example 2 and Table 2, the press pressure can be selected arbitrarily. This shows that the bulk density can also change.

patent applicant IBIDEN Co., Ltd. Representative Jun Taga

Claims (1)

[Claims] 1. Disperse ceramic fibers and fine clay minerals in water, then add at least one type of cationic organic or inorganic flocculant to form a ceramic fiber flock containing clay minerals. A method for producing a ceramic fiber molded body, comprising depositing the flocs on the surface of a porous mold connected to a vacuum suction device, and pressing a press mold against the floc deposits. .