JPS61132340A - Multilayer molded shape by inorganic fiber and manufacture thereof - Google Patents

Abstract

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

Description

[Detailed Description of the Invention] Purpose of the Invention (Field of Industrial Application) The present invention is a multilayer molded product made of inorganic fibers, more specifically, a multilayer molded product made of two types of inorganic fibers having different alumina contents. The present invention relates to a multilayer molded product and a method for manufacturing the same.

(Prior art) Conventionally, as a type of molded product, △lzOa S containing 40 to 60% by weight of AIzO,j: Molding consisting of a fiber layer in which Or-based glass fibers, that is, ceramic fibers are bonded with an inorganic binder. The product is known.

(Problems to be Solved by the Invention) Molded articles made of ceramic fibers are used for various purposes such as heat insulating materials, sealing materials, and backing materials, and exhibit corresponding effects.

However, the temperature it can withstand up to 1100
℃, it is difficult to use the molded product above that temperature, and when used for a long period of time, the molded product suffers from thermal deterioration, cracking, and shrinkage deformation.

Therefore, it is conceivable to manufacture the above-mentioned molded product using inorganic fibers with a high alumina content, but if the alumina content in the inorganic fiber is increased, the resulting molded product will become expensive. It was economically disadvantageous to manufacture the entire product from inorganic fibers with a high alumina content.

Therefore, an object of the present invention is to provide, at a low price, a multilayer molded product that can have a high maximum operating temperature, can be used for a long period of time, and does not shrink.

Structure of the Invention (Means for Solving Problems) An object of the present invention is to provide a fiber layer (A) on one side of which Al2O,/-8ioz ceramic fibers containing 40 to 60% by weight of AlzOJ are bonded with an inorganic binder. Or on both sides,
A Iz Q containing 75 to 90% by weight of Al2O,r
This is achieved by forming a multilayer molded product characterized by covering a fiber layer (B) in which J-3iQ2 alumina fibers are bonded with an inorganic binder.

Further, the multilayer molded product is made of a suspension in which Al20J-3iOz ceramic fibers containing 40 to 60% of A1203 are suspended in an aqueous solution containing an inorganic binder;
AlzOJ containing 75 to 90% by weight of I, Z QJ
Any one of the suspensions in which 5iOL-based alumina fibers are suspended in an aqueous solution containing an inorganic binder is filtered through a filter to form a fiber layer on the filter, and then the resulting fiber layer The remaining suspension is filtered to form another fibrous layer on the fibrous layer.

(Function) In the multilayer molded product according to the present invention, the fiber layer made of the ceramic fiber is protected by the fiber layer made of alumina fiber, and the fiber layer of the alumina fiber itself of the molded product can be used satisfactorily even under high temperatures. withstand

Furthermore, in the method of the present invention, on top of one fiber layer once formed on the filter, another fiber layer that is easily compatible with the same fiber layer is piled up without forming a clear boundary. The fiber layers of the multilayer molded product do not separate.

Therefore, the multilayer molded product according to the present invention has high mechanical strength.

(Example) The present invention will be described in detail below with reference to FIGS. 1, 2, 3, and 4.

1.0% by weight of ceramic fibers containing 50% by weight of Al2O was suspended in an aqueous solution containing 0.1% by weight of fine-particle alumina sol, and the suspension of ceramic fibers was poured into one tank. Adjustments were made while stirring in the

Alumina, which acts as an inorganic binder, was coated around each ceramic fiber in the resulting suspension.

A cylindrical suction filter 1 shown in FIG. 1 was immersed in the suspension.

The suction filter 1 is formed from a cylindrical wire mesh 2 constituting one side of a mold, and disks 3 and 4 provided at both ends of the wire mesh 2 to act as a frame of the mold, the three mentioned above being not shown in the figure. It is supported by a wire mesh support member that is not attached.

A suction pipe 5 is attached to the disc 3, and the suction vibe 5 is communicated with a vacuum generation source (not shown).

Therefore, when a suction filter is immersed in a tank containing a suspension of ceramic fibers and a vacuum source is activated, the filter suctions the aqueous solution in the suspension through the wire mesh 2. .

The other disc 4 can be removed from the wire mesh support member.

Note that the distance between the surface of the wire mesh 2 and the outer peripheral surface of the disk 3.4 is 1 cm.

In this way, an IM fiber layer A of ceramic fibers was formed on the surface of the wire mesh 2, as shown in FIG.

On the other hand, a suspension of 4M alumina in which 1.0% by weight of ceramic fibers containing 80% by weight of Al2Qj were suspended in the aqueous solution was prepared under stirring in a tank different from the above-mentioned tank.

The periphery of each alumina fiber in this suspension was also coated with alumina and silica, which acted as an inorganic binder.

A fibrous suction filter 6 in which a ceramic fiber layer A shown in FIG. 2 is formed on the surface of a wire mesh 2 is placed in this tank to create a vacuum source.
I let it happen.

Then, as shown in FIG. 3, a fibrous layer B containing alumina sol was formed on the surface of the fibrous layer suction filter 6.

Next, the disk 4 is removed from the wire mesh support member and the two-layer laminate product in which the fiber layer Δ of ceramic fibers is covered with the fiber layer B of alumina fibers is extracted, and the cylinder shown in FIG. A two-layer molded article 7 was obtained.

Although it was not possible to immediately distinguish between the ceramic fiber layer A and the alumina fiber raN fiber layer 11B constituting this molded product 7, when this molded product was heated at 16oC for a long time, the two fibers 11A Boundary 8 between and B was almost confirmed from the fact that the color tones of both layers were different.

Although the boundary 8 between both fiber layers A and 8 was not clear,
When the approximate thickness of the fiber layer B was measured, it was found to be approximately 2 mm.

A thermometer was inserted into the hollow part of the cylindrical two-layer molded product 7 obtained in this way, and the molded product was used as a backing material for temperature measurement in a heating furnace. It was possible to use it for a long time.

For comparison, we used a molded product in which the fiber layer B was not N-treated and had the same thickness, and its lifespan was similar to that of the molded product obtained in the example of the present invention. Approximately 1/3
It turned out to be.

As described above, in the molded product consisting of two fiber layers of inorganic fibers with different alumina contents, the fiber layer A of ceramic fibers with an alumina content of 40 to 60% by weight was obtained in this example. Since the surface part of the molded product is covered with a fibrous layer B made of alumina sol with an alumina content of 75 to 9Q% by weight, it can withstand higher temperatures than conventional molded products and can also withstand long-term use. found.

Since the same type of compound as ceramic fibers and alumina fibers was used as a binder, the binding force between the fibers was also strong.

Note that the present invention is not limited to the above-mentioned embodiments, but can also be implemented in the following embodiments.

Any ceramic fibers with different contents of 5 iOz can be used as long as the alumina content in the ceramic fibers is within the range of 40 to 60% by weight.

Any alumina fibers with different s r O2 contents can be used as long as the alumina content in the alumina fibers is in the range of 75 to 90% by weight.

In particular, those having a high content are preferably used.

Note that if the alumina content is less than 75% by weight, the effects of the present invention will not be sufficiently exhibited.

As the binder, colloidal silica and similar inorganic binders can be used for alumina sol.

The multilayer molded product may be in the shape of a flat plate as shown in FIG. 5, or it may be formed into the shape of a fire bed of a household combustion appliance as shown in FIG.

Also, as a mold, it is sufficient that only one layer leaks on one side.
When obtaining a more three-dimensional molded product, it is possible to use a molded product that is further equipped with a mold that matches the shape.

In addition to wire mesh, materials for the filtration layer include cloth, sintered metal,
Punched metal or other similar materials are used.

In addition, in the multilayer molded product 7 in Fig. 5, I!
A fibrous layer B of alumina fiber is coated on the male layer A, and the fibrous layer B of alumina fiber is provided inside the multilayer molded product 7 serving as the fire bed in FIG.

In addition, the alumina fiber layer B can be coated not only on one side of the ceramic fiber layer A but also on both sides of the ceramic fiber layer A. In this case, the alumina fiber suspension is first coated, and then the ceramic fiber layer B is coated with the alumina fiber suspension. and finally the alumina fiber suspension again through a suction filter.

Effect of the invention The present invention exhibits the following effects.

In the multilayer molded product of the present invention, the fibrous layer of ceramic fibers is coated with the fibrous layer of alumina fibers whose alumina content is 15% or more by weight more than the alumina content of the fibers. If the molded product is used on a surface that receives high temperature islands, the molded product will withstand the use satisfactorily and will have a long life.

Since only the surface portion of the multilayer molded product is coated with the fiber layer of alumina fiber, the amount of alumina fiber used can be reduced. Therefore, the molded product is of low quality despite its high quality.

On top of the fiber layer formed on the filter, another type of fiber layer is coated and laminated using water and suction power, which promotes the entanglement of the two types of fibers and increases the strength of the multilayer molded product. improves.

[Brief explanation of drawings]

Figure 1 is a perspective view of a suction filter, Figure 2 is a perspective view of a fiber layer of ceramic fibers on the suction filter, Figure 3 is a perspective view of a fiber layer with alumina content on the ceramic fiber layer, and Figure 4 is a perspective view of a fiber layer with alumina content on the ceramic fiber layer. FIG. 5 is a perspective view of a multilayer molded product according to an embodiment of the present invention, FIG. 5 is a perspective view of a molded product according to the embodiment of the present invention, and FIG. 6 is a similar perspective view. Multilayer molded product 7, fiber layers A and B Patent applicant Kyowa Kogyo Co., Ltd. Agent Patent attorney On 1) Hironobu Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. Al_ containing 40 to 60% by weight of Al_2O_3
Al
Al_2O_3 containing 75 to 90% by weight of _2O_3
-A multilayer molded product made of inorganic fibers, characterized in that SiO_2-based alumina fibers cover a fiber layer (B) bonded with an inorganic binder. 2. Al_ containing 40 to 60% by weight of Al_2O_3
A suspension in which 2O_3-SiO_2 ceramic fibers are suspended in an aqueous solution containing an inorganic binder, and an Al_2O_
Al_2O_3-SiO containing 75 to 90% by weight of 3
Any kind of suspension in which _2-based alumina fibers are suspended in an aqueous solution containing an inorganic binder is filtered through a filter to form a fiber layer on the filter, and then the obtained fiber layer is 1. A method for producing a multilayer molded article using inorganic fibers, which comprises filtering the remaining suspension to form another fibrous layer on the fibrous layer. 3. The method for producing a multilayer molded product using inorganic fibers according to claim 2, wherein the filter is provided on one surface of the mold. 4. The method for producing a multilayer molded product using inorganic fibers according to claim 2, wherein the filter is a suction filter.