JPH0449513B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for manufacturing a fibrous molded article having excellent fire resistance and high strength with excellent productivity. BACKGROUND TECHNOLOGY For fibers such as glass fibers, ceramic fibers, and rock wool, which are manufactured by converting a melt of a raw material into fibers, the fibers are produced while the raw melt exits a fiber-forming device and solidifies to form fibers. The organic adhesive is sprayed onto the fiber collection surface while it falls through the air, and the fiber aggregate with the adhesive attached is formed into the desired shape and dried (the contact agent When using a thermosetting resin, there is a method of obtaining a fibrous molded product by heat treatment (including heat treatment for curing the resin), but products made by this method have poor strength because the contact agent decomposes when exposed to high temperatures. The deterioration is significant, and therefore it is not suitable for heat insulating materials that require fire resistance. In order to take advantage of the excellent fire resistance of fiber materials, inorganic adhesives are used in the above manufacturing method.
For example, methods using sodium silicate, colloidal silica, aluminum phosphate, etc. cannot increase the solid content of the adhesive used in the form of an aqueous solution or dispersion, so sufficient adhesive must be attached to the fibers. The adhesive may react with the fibers and deteriorate them at high temperatures; for the above reasons, products tend to have high porosity and poor insulation performance. However, there are problems such as, fire resistance is not so good; and there are no examples of a fire-resistant fibrous molded article actually being produced by this method. Therefore, when using an inorganic adhesive, some methods involve producing fiber without adhering the adhesive during the fiber manufacturing process, impregnating it with a sufficient amount of inorganic adhesive, shaping it, and drying it. It is being carried out in However, this manufacturing method not only complicates the process but also makes it impossible to carry out the process from spinning to molding in a continuous process.Also, because the molded fiber aggregate has a high moisture content, it takes time and heat energy to dry it. This is extremely disadvantageous in terms of production costs. Moreover, the process of stirring and mixing the fibers and adhesive damages the fibers, making it difficult to produce products with low density and high strength. Problems to be Solved by the Invention In view of the fact that the conventional method for producing a fire-resistant fibrous molded product had the above-mentioned drawbacks, the present invention aims to provide high quality with high productivity and low cost. The present invention aims to provide a method for producing a fire-resistant fibrous molded article. Means for Solving the Problems The means adopted in the present invention to solve the above problems is to melt glass or mineral materials as fiber raw materials to form fibers, and to make the formed fibers into fibers. Before reaching the collection surface, a highly concentrated aqueous dispersion of kaolin clay (hereinafter referred to as clay) containing a deflocculant is sprayed together with the adhesive to collect the fibers to which the clay and adhesive have adhered. It is characterized by being dried after being molded into a desired shape. Hereinafter, the manufacturing method of the present invention will be explained in detail in order of steps. In the manufacturing method of the present invention, the method of melting the fiber raw material glass or mineral substance to make fibers is optional, but the raw material melt exits the fiberizing device, solidifies, and forms fibers while air blowing onto the fiber collection surface. Since the clay water dispersion is sprayed while being sent by air or falling through the air,
It is desirable to employ a fiberization method that is convenient for such processing. Suitable clays to be attached to the fibers include those that can be easily peptized, such as kaolinite, nacrite, dateskite, and halloysite. Clay minerals other than the kaolin group, such as talc,
Mica, vermiculide, etc. cannot be used in the same way as kaolin group clays because they are difficult to peptize sufficiently and therefore a high concentration dispersion of low clay cannot be obtained. In addition, together with the clay, other refractory inorganic powder materials such as pearlite, mica, wollastonite, calcium carbonate, calcium silicate, aluminum sludge, etc. may be used in combination within a range of approximately 50% by weight based on the clay. You may. When these powdered inorganic materials are attached to fibers in appropriate amounts, they have the effect of reducing the strength of the product, especially the decrease in strength when heated to high temperatures, and also have the effect of improving heat insulation performance. In particular, the above effect is remarkable for clay, probably because it has crystallization water. The deflocculant acts to promote the dispersion of fine clay particles in water and form a clay dispersion with a low clay content to the extent that it can be sprayed as fine droplets even at high concentrations. In order to make the solid content concentration as high as possible, preferably about 50 to 300% by weight of water based on the clay (if other refractory inorganic powder materials are used together, about 50 to 300% by weight based on the total amount of these and clay). 100% by weight). Specific examples of preferable deflocculants include sodium pyrophosphate, sodium silicate,
Examples include soda carbonate and sodium aluminate. The addition rate of the deflocculant is preferably about 0.05 to 5% by weight based on the clay. Further use of peptizer will not further reduce the viscosity, and large amounts of peptizer may degrade the fire resistance of the fibers. Adhesives are used to bring the normal strength of a product to the level required for practical use. As the adhesive used in the manufacturing method of the present invention, any of organic adhesives such as phenolic resin, starch, carboxymethylcellulose, and poval, and inorganic adhesives such as sodium silicate, colloidal silica, and alumina sol can be used. May be used together.
The adhesive may be easily sprayed as an aqueous solution alone, or may be added to the clay dispersion as described above. A clay dispersion liquid, an adhesive solution, or a mixture of the two having the composition described above is sprayed onto the fibers, and the position is such that the fibers formed from the raw material melt are blown onto the fiber collection surface of a belt conveyor. Let this be the space it takes to reach . The spray amount should be set so that approximately 5 to 80% by weight of clay adheres to the fibers, and that the adhesive adheres to the fibers and clay (or the total amount of clay and clay if other fire-resistant inorganic powder materials are used together). Approx. for total amount
It is desirable to select so that 0.5 to 10% by weight is deposited. Adding clay in excess of the above range increases the density of the product, worsens its insulation properties, and causes the fibrous molded product to lose its characteristics, so it should be avoided unless a high-density product is intentionally manufactured. desirable. In addition, excessive use of adhesives, especially organic adhesives, impairs the fire resistance of the product, so it is desirable not to use more adhesives than necessary. Next, the fibers with the clay and adhesive attached are collected and formed into the desired shape, but when forming into a long sheet, the fibers are deposited at a constant thickness on a fiber collection surface like a belt conveyor. It is then compressed in the thickness direction. After that, let it dry and harden the adhesive.
A fibrous refractory material is obtained in which a refractory material such as clay is filled between the fibers and its normal state is fixed with an adhesive. EXAMPLES The present invention will be described below with reference to Examples and Comparative Examples. Examples 1 and 2; Comparative Examples 1 and 2 Blast furnace slag, basalt, etc. are melted in a cupola and made into fibers using a high-speed rotating body, and then immediately dispersed with a refractory material such as clay to the ratio shown in Table 1. A liquid (containing adhesive) was sprayed and received on a conveyor-like fiber collection surface, and the accumulated fibers were continuously compression-molded, dried, and cut. However, in the case of Comparative Example 2, the moisture content of the fiber aggregate was high and continuous treatment was not possible. Comparative Example 3 Rock wool separately manufactured in the same manner as in Example 1 was mixed with clay and clay in the proportions shown in Table 1.
The mixture was poured into water together with mica, pearlite, and wollastonite, stirred and mixed, and then an aqueous starch solution was added and mixed. After adding a flocculant, the mixture was dehydrated and dried. The characteristic values of the products according to each of the above examples are shown in Table 1 along with the manufacturing conditions. The 10% compressive strength shown in the same table refers to the length A cm, the width B cm, and the thickness C cm of the specimen (A
×B is the value calculated from the following formula by measuring the load L required to compress approximately 50 cm ² ) by 10% in the thickness direction using a tensilon. 10% Compressive Strength=L/A・B Examples 1 and 2 had good productivity and product properties, and the product of Example 2 in particular had excellent high temperature properties. In Comparative Example 1, the product had poor heat resistance;
By heating to 100℃, it became sintered (for this reason,
(The measured value shows a large value). In Comparative Examples 2 and 3, since a large amount of water had to be deposited, it took a long time to dry, and the product properties were also slightly inferior. Effects of the Invention The manufacturing method of the present invention not only improves the strength, heat resistance, fire resistance, and insulation properties of the product by filling and fixing clay between the fibers as described above, but also allows the entire process to be carried out continuously. Moreover, since the amount of water adhering to the fibers is kept to a minimum, it is easy to handle intermediate products during the molding process, and the drying process is easy.

【table】

[Table] It has the advantage that the amount of heat required for drying is extremely small and the time required for drying is short. Therefore, according to the present invention, it is possible to produce a high-performance fire-resistant fibrous molded article with better productivity and lower cost than ever before.

Claims (1)

[Claims] 1. A kaolin group clay aqueous dispersion containing a flocculating agent in a space where glass or mineral material capable of forming fibers is melted to form fibers and the formed fibers reach a fiber collection surface. A liquid with a water content of 50 to 300% by weight based on the clay is sprayed together with an adhesive to adhere to the fibers, the fibers with the kaolin group clay and adhesive attached are collected, formed into a desired shape, and then dried. A method for producing a fire-resistant fibrous molded article. 2. The manufacturing method according to claim 1, wherein the adhesive is sprayed simultaneously with, but separately from, the kaolin group clay aqueous dispersion. 3. The manufacturing method according to claim 1, in which 5 to 80% by weight of kaolin group clay is attached to the fibers.