JPH04275102A - Preparation of nonflammable formed material - Google Patents

Abstract

PURPOSE:To provide a formed material, such as paper and sheet, having the properties of high strength, light weight and good processability together with high-temperature resistance, fireproof, and high thermal conductivity. CONSTITUTION:Inorganic fibers are dispersed into the solution prepared by dispersing clay powder comprising 40-70wt.% of SiO2, 4-10wt.% of Al2O3, 5-20wt.% of MgO, and 5-15wt.% of H2O in water. Water is removed from the fiber-dispersed solution to prepare a formed material comprising inorganic fibers which is then dried to obtain the nonflammable formed material.

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 a nonflammable molded article used as an ultra-high temperature heat-resistant material.

0002

BACKGROUND OF THE INVENTION As a noncombustible molded article, for example, inorganic paper whose main raw material is inorganic fiber is known. When producing high-temperature paper like this, the fibers are made using a paper machine using a binder.There are two types of binders, organic and inorganic, but it is difficult to manufacture paper using only inorganic binders. It lacks adhesive strength and is difficult to manufacture, requiring the combined use of an organic binder. Inorganic paper manufactured using an inorganic binder is 500
The organic matter must be incinerated by firing at ~800°C, but in this case, there is a problem that the strength of the resulting inorganic paper is not sufficient with only the remaining inorganic binder. Furthermore, this problem is not limited to inorganic paper, but also applies to molded bodies made of other inorganic fibers. As a method for producing a sheet-like product made only from inorganic fibers, a method using sepiolite mineral staple fibers as a binder is known, but the strength of the sheet-like product obtained in this case was also not sufficiently satisfactory.

0003

[Problems to be Solved by the Invention] The present invention has been made based on the above-mentioned circumstances, and it has excellent high-temperature resistance, fire resistance, and thermal conductivity, as well as high strength, light weight, and excellent workability. The present invention provides a method for manufacturing paper, sheets, and other molded objects.

0004

[Means for Solving the Problems] As a result of extensive research in order to solve the above problems, the present inventors have found that by using a specific clay that dissolves in water as a binder when producing molded bodies from inorganic fibers, The inventors have found that the above object can be achieved, and have completed the present invention based on this finding.

That is, the present invention uses inorganic fibers with SiO2 content of 40 to 70% by weight, Al2O3 content of 4 to 10% by weight, Mg
A clay powder containing 5 to 20% by weight of O and 5 to 15% by weight of H2O is dispersed in a dispersion solution in which water is dissolved and dispersed, and water is removed from the resulting fiber dispersion to produce inorganic fibers. The present invention provides a method for producing a nonflammable molded article, which comprises forming a molded article and drying the molded article.

[0006] As the inorganic fibers used in the present invention, for example, ceramic fibers, alumina fibers, rock wool fibers, glass fibers, silicon nitride fibers, silicon carbide fibers, carbon fibers, zirconia fibers, etc. are preferably used. These fibers may be used alone or in combination. The fiber length is preferably 2-3
0 mm, the fiber diameter is preferably 2-5 μm.

The clay powder having the above composition used in the present invention is preferably one that can dissolve 10 g or more per liter of water at room temperature. For example, Jiangxi clay powder produced in Jiangxi Province, China is preferably used. It is preferable to dry the clay at 50 to 300°C and use it as a powder of 10 to 300 mesh.

In the present invention, preferably 0.1 to 3 parts by weight of clay powder per 100 parts by weight of water is poured into water and sufficiently stirred to form a clay powder dispersion solution. Although it is preferred that the clay powder is completely dissolved in the water, it is not necessary that all the clay powder be dissolved in the water as long as the clay powder is uniformly dispersed in the water. Therefore, the dispersion solution in the present invention refers to both a solution in which the clay is completely dissolved in water and a solution in which the clay is uniformly dispersed in the solution without being partially dissolved.

Next, preferably 400 to 2000 parts by weight of the dispersion solution of the clay powder obtained above is added to 100 parts by weight of the inorganic fibers, and stirring is performed until the fibers are uniformly dispersed in the solution. At this time, if necessary, use alumina sol,
Addition of inorganic substances such as silica sol, zirconia sol, sodium phosphate, bentonite, cordierite, zeolite, magnesia, and yttria improves the heat resistance of the resulting molded product. The amount of these additives is preferably 10 to 100 parts by weight per 100 parts by weight of clay powder. The clay powder and the inorganic substance can also be mixed in advance and made into a slurry, which can then be added to water.

[0010] Next, when a flocculant such as a polymer flocculant is added, the clay adheres to the inorganic fibers and the fibers coagulate. Moisture is appropriately removed by natural filtration, vacuum filtration, or other methods. The amount of flocculant is preferably 3 to 10 parts by weight per 100 parts by weight. The aggregated fibers and clay are made into paper or molded into various shapes by a known method. Molding methods include casting, extrusion, hot rolling, doctor blading, paper making, vacuum suction, etc. If the material formed by these methods is a sheet, it may be folded, bent, etc. It can be cut, pasted together, and processed into complex shapes. Next, this molded body is preferably heated to 40
Drying at ~120°C for 1 to 5 hours yields the desired nonflammable molded product. This molded body is more preferably 800~
When fired at 1200°C, organic substances and impurities contained in the clay are removed, and inorganic substances in the clay are sintered, improving heat resistance. In this case, even if the organic matter is removed, the shape is retained by the clay.

[0011]

EXAMPLES The present invention will be explained in detail below based on Examples, but the present invention is not limited thereto. Example 1 10 parts by weight of Jiangxi clay was added to 300 parts by weight of water in a propeller type stirrer (physical properties and chemical components are shown below).
Add the clay to the water, stir for a few minutes, and confirm that the clay has dissolved in the water. Next, ceramic fiber (Nippon Steel Chemical SC Fiber 1400) was added to 300 parts by weight of this solution.
100 parts by weight of alumina (44% by weight, silica 56% by weight) and 3 parts by weight of glass fibers were added and stirred, then 5 parts by weight of alumina sol was added and stirred until the fibers were uniformly dispersed in the water. Next, 2 parts by weight of Himoroc (trade name, manufactured by Kyoritsu Organic Co., Ltd.) as a polymer flocculant was added to this fiber dispersion to coagulate the fibers, and then the fibers and water were separated, and a paper towel with a thickness of 0 .4mm paper was produced. This was cut into 20 mm width x 200 mm length, and the tensile strength was determined. Table 1 shows the physical properties and strength test results of this paper.

0012

[Table 1]

Physical properties
Chemical composition
(Weight%) Relative density 2.40~
2.60 SiO2
60.43 Bulk density 300
Al2O3
6.38 bulk density
525
Fe2O3 2.30pH
9±0.5
MgO 14
．． 38 surface area 259
CaO
1.28 whiteness
65 K2
O 0.54CEC
26
Na2O
0.19 (cation exchange rate)
TiO2
0.22 Decolorizing power
200 MnO
0.56 moisture (%)
<15
H2O 11.83 Fluid powder
Amount lost by fire (1000℃) 13.3
6
molecular structure formula

{Ca0.10K0.09N0.0
4}
(Mg5.46Al1
．． 11Fe3+0.51
T
i0.02) [Si11.49Al0.51]

O30(OH)4(OH2)48H
2O

Example 2 Example 1 except that 75 parts by weight of rock wool fibers, 20 parts by weight of ceramic fibers and 5 parts by weight of glass fibers were used instead of 100 parts by weight of ceramic fibers and 3 parts by weight of glass fibers in Example 1. Paper of a similar shape was obtained in the same manner as in Example 1. Table 1 shows the physical properties and strength test results of this paper.

Example 3 A fiber dispersion was prepared using the same formulation as in Example 1, and a board having a thickness of 20 mm and a length and width of 300 mm was formed using a vacuum forming machine. From this board length 200mm width 40
A test piece with a thickness of 20 mm was cut out, and its bending strength was determined using a three-point bending tester at a loading rate of 1 mm/3 minutes. Table 1 shows the physical properties and strength test results of this board.

Example 4 In place of 100 parts by weight of ceramic fibers and 3 parts by weight of glass fibers in Example 1, alumina fibers (electrochemical arsene 8
Paper of the same shape was obtained in the same manner as in Example 1, except that 80 parts by weight of 0), 20 parts by weight of ceramic fibers, and 3 parts by weight of glass fibers were used. Table 1 shows the physical properties and strength test results of this paper.

Example 5 17 parts by weight of a slurry obtained by kneading 300 parts by weight of water and 10 parts by weight of Jiangxi clay and aluminum sol in a weight ratio of 10:7 was put into a propeller type stirrer. , stir for a few minutes and make sure the clay has dissolved in the water. Next, 100 parts by weight of ceramic fiber (Nippon Steel Chemical SC Fiber 1400 44% alumina, 56% silica) and 3 parts by weight of glass fiber were added to 300 parts by weight of this solution and stirred until the fibers were uniformly dispersed in the water. conduct. 2 parts by weight of Hymoloc as a coagulant was added to this dispersion to coagulate the fibers, and then the fibers and water were separated, and paper with a thickness of 0.4 mm was produced using a hand-sheeting machine. Width 20
It was cut to 200 mm x length and subjected to a tensile test. Table 1 shows the physical properties and strength test results of this paper.

[0018]

[Effects of the Invention] According to the present invention, it has been possible to obtain molded articles such as paper, sheets, etc., which are excellent in high-temperature heat resistance, fire resistance, and thermal conductivity, as well as having high strength, light weight, and excellent workability. In particular, when made into paper, paper with the same flexibility as conventional paper was obtained using only an inorganic binder.

Claims (1)

[Claims] Claim 1: Inorganic fibers are dispersed and dissolved in water by clay powder containing 40 to 70% by weight of SiO2, 4 to 10% by weight of Al2O3, 5 to 20% by weight of MgO, and 5 to 15% by weight of H2O. 1. A method for producing a nonflammable molded article, which comprises dispersing the fibers in a dispersion solution containing inorganic fibers, removing water from the resulting fiber dispersion to obtain a molded article made of inorganic fibers, and drying this.