JPS58167463A - Refractory and heat-insulative construction board - 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 producing a fire-resistant, highly insulating, lightweight construction board made of wood strips and a hydraulic binder.

Conventionally, wood wool cement boards, wood chip cement boards, wood wool gypsum boards, etc. are known as architectural boards made of wood chips and hydraulic binding materials, but these are usually made of wood wool or wood chips. After kneading the thin strips and the hydraulic binder with water, they are dispersed on a mold and pressure-molded to make a plate-shaped molded body, which is dried after curing. It is built. In this case, the volume ratio of the wood strips and the hydraulic binder is 1:1 to 21 degrees, and the specific gravity of the constructed architectural board is approximately 0.5 to 0.8, with 30 to 70% of the air voids remain.

The present inventors have conducted various studies in an attempt to create a wooden building board that reduces its own weight and has improved heat insulation and fire resistance. Wooden building boards, such as wood wool cement boards, are designated as legally quasi-noncombustible materials under the Building Standards Act.These building boards are required to be light and at the same time highly noncombustible, so they are certified as quasi-noncombustible materials. In order for all the pieces to pass the test method (JIS A 1321), the weight of wood wool must be 30% or less, the cement must be 10% or more, and the specific gravity must be 0.7 seconds. In the conventional method, even if the amount of cement used is increased, the cement paste with the addition of water that can be manufactured has high fluidity, and even if this paste is applied to the wood strips, the surface of the wood strips will be thick. Pour it without covering it, fill the void,
The insulation and sound absorption properties are low, and an irregular cement paste layer is formed on the back side, spoiling the aesthetic appearance of the building board.

In this way, wood chips, which are naturally highly flammable, and hydraulic binding materials are used, and a cloudy void is left inside to ensure heat insulation, sound absorption, and economic efficiency. Therefore, it was extremely difficult to make a highly fire-resistant construction board, so for example, using a hydraulic binder mixed with a small amount of filler, the voids were almost completely filled and the strips were protected from the heat of the fire. How to protect (
0) A method has been considered in which the surface is coated with a hydraulic binder and this paint film is used to obtain fire resistance.

However, in the method (a) above, the raw material used is uneconomical, the insulation and sound absorption properties are reduced, and f! Method (B) has the disadvantage of increasing fog, and as with method (B), it is uneconomical, has low sound absorption, and increases weight, as well as the shrinkage rate of the board and surface layer. There were problems such as warping due to differences in the bonding, peeling between the two, and cracking.

According to Yuto, the inventors of the present invention conducted various experiments to increase the viscosity of the hydraulic binder paste and increase the thickness of the refractory heating layer attached to the surface of the wood strips. There is a method of mixing powder into the paste, but we have found that the most effective way to further improve the thermal insulation properties of the paste is to mix in foamed inorganic mineral beads of a specific particle size and specific gravity.

Next, the experimental results will be explained.

Portland cement was used as a hydraulic binder, 100 parts by weight of water was added to 100 parts by weight of this cement, and the mixture was kneaded and used as a cement paste. The wood strips used had a maximum length of 45 cm, an average of 5 cm, and an average thickness of 0.5 cm. The foamed inorganic mineral is made by crushing pyroelectric 6, firing it and foaming it, with a bulk specific gravity of 0.04 to 0.20 and a particle size of 2.5-1, passed through a sieve.
．． Perlite powder or beads that passed 90% or more of 2+++el were used.

Add real chips and perlite to cement paste so that the ratio is cement/wood chips = 1.8 and pearlite/wood chips = 0.2 and knead (), and the surface of real chips and beads Pour the paste onto the board formwork,
When building boards were made by pressurizing them in water at a molding pressure of 1 ko/CI2 and molding the product to a thickness of 15 mm, the ratio ◆ of the product was 0.6 and the dry bending strength of the product was 10K.
g/cgi2. In the flame retardancy test of J Is A1321, the concentration time area is O(T:.

Minutes) and departure! A coefficient of 0.3 and an afterflame time of 0 seconds were obtained.

The reason why such excellent results were obtained in this experiment is that by kneading the cement paste and pearlite, the viscosity of the cement paste becomes normal and a cloudy fire-resistant coating layer is formed on the surface of the wood chips. This is because the board hardened, leaving many voids inside the board.

The present invention is a method based on this knowledge, and in manufacturing a building board using real silk F1 and a hydraulic binder, a paste with a specific gravity of hydraulic binder:water of 0.8 to 1.2, Ratio 11
0.04-0.20, passed through a 2.5I spade sieve, 1
．． 2mg + foamed inorganic mineral powder or beads that pass 90% or more through a sieve and this strip in a weight ratio of hydraulic bond 44/wood strips = 0.8 to 2 and foamed inorganic mineral powder or beads to wood strips Φ Mix the paste so that the ratio is 10 to 20%, sprinkle the paste on the surface of the wood wire and the powder or beads, pour it onto a board form, pressurize it, form it into a plate shape, harden it, and remove the mold. This is a method for manufacturing a building board with excellent fire resistance and heat insulation properties.

In the present invention, the term "wood chips" refers to wood wool or wood chips obtained by sawing wood, and as the hydraulic binder, usually Portland cement or hydraulic gypsum is used. In addition, the foamed inorganic minerals used are crushed pieces of minerals that expand when heated, such as pearlite, vermiculite, vermiculite, and shirasu, which are fired and foamed, and then crushed, and the particle size is within the above-mentioned range. be.

Addition of expanded inorganic mineral beads to wood chips - 10% (
As the weight [1] increases, the heat resistance of the product increases, but since the adhesive strength decreases, it is desirable to add up to 20%.

According to the present invention, by mixing a specific amount of foamed inorganic mineral powder or beads with a specific particle size into a building board,
Since it is possible to prepare architectural boards that have passed the A1321 standards for quasi-noncombustible materials, its industrial effects are great.

Example Wood wool with a maximum length of about 45 cm and an average thickness as shown in the following table and the same pearlite used in the experimental example were mixed in the proportions shown in Table 1. 1. Pour into cement paste mixed in the ratio shown in Table 1 and stir to evenly sprinkle the paste on the surface of the wood wool and perlite, then put it into a board formwork and cover the surface with 1 kg/c
Apply pressure to +e' to form a flat plate with a thickness of 20+ei.
After curing, building boards as shown in Tables 1 and 2 were made.

Claims (1)

[Claims] When manufacturing architectural boards using wood strips and hydraulic binding material, paste with a specific gravity of 0.04 to 0.20 is added to a paste with a weight ratio of two hydraulic binding materials of 0.8 to 1.2. Hydraulic binder/wood chips = 0. .8 to 2 and the foamed inorganic mineral powder or beads to this strip are mixed at a weight ratio of 10 to 20%, and the surfaces of the wood strip and the powder or beads are sprinkled with paste. Manufacture of architectural boards with excellent fire resistance and heat insulation properties, characterized by pouring onto board formwork, pressurizing, molding into a plate shape, sanding, and demolding 7J
Payment.