JPH05200716A - Production of inorganic cement panel - Google Patents

Abstract

PURPOSE:To produce an inorg. cement panel having deep embossed patterns applied thereto by a wet method, having mechanical strength and improved in frost damage resistance. CONSTITUTION:A slurry based on hydraulic cement and water is formed into a mat by papermaking method and the surface of the slurry immediately after formation is roughened and a cement molding material 2 based on hydraulic cement with water content of below 50% is sprinkled over the roughened surface of the mat 1 and subsequently subjected to pressure molding to be cured and hardened.

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 an inorganic cement board used as a building board or the like.

[0002]

2. Description of the Related Art Conventionally, a wet method and a dry method have been generally used as a method for producing a cement-based building board mainly composed of hydraulic cement. The wet method is a method for making noodles and a slurry, and the dry method is a method adopted for manufacturing wood chip cement boards and wood wool cement boards.

[0003]

The most different point between these two construction methods is the difference in the amount of added water. That is, the wet method uses a large amount of water, whereas the dry method minimizes the use of water. The difference between the products is that the dry method gives a complicated pattern with deep surface embossing, but the mixing and dispersion of the molding material is not sufficient as compared with the wet method, resulting in a problem that the mechanical strength is inferior. In order to solve this problem, the present applicant has already prepared a slurry containing hydraulic cement and water as main components by a papermaking method, and the water content on the mat immediately after papermaking does not exceed 50%. Disperse the cement molding material whose main component is hard cement,
Then, a method for producing an inorganic cement board, which is then pressure-molded and then cured by curing, has been developed and filed (Japanese Patent Application Laid-Open No. 61-
However, according to this method, there is a problem that the interfacial adhesion between the mat and the cement molding material is not sufficient, and the frost damage resistance is poor.

The present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention that a deep embossed pattern can be formed by a wet method, mechanical strength can be secured, and resistance to An object of the present invention is to provide a method for producing an inorganic cement board having good frost damage.

[0005]

Means for Solving the Problems The method for producing an inorganic cement board according to the present invention is a method in which a slurry containing hydraulic cement and water as main components is made by a papermaking method to roughen the surface of a mat 1 immediately after papermaking. Cement molding material 2 whose main component is hydraulic cement having a water content of not more than 50% is sprinkled thereon, followed by pressure molding, followed by curing and hardening. The above-mentioned technical problem is solved by.

[0006]

The surface of the mat 1 immediately after the papermaking is roughened, and the cement molding material 2 whose main component is hydraulic cement whose water content does not exceed 50% is sprinkled on the surface of the mat 1 and then pressure-molded. Can form a deep uneven pattern, and the cement molding material 2 can secure the mechanical strength, and the interfacial adhesion between the mat 1 and the cement molding material 2 can be increased.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. The mat in the present invention is formed by a paper-making method, and the slurry may be a mixture of reinforcing cement mainly composed of hydraulic cement,
The composition is not particularly limited. In the present invention, the slurry is drawn up by a papermaking method to form the mat 1, and the surface of the mat 1 immediately after the papermaking is roughened. For example, as shown in FIG. 1, the surface is roughened by demon rolls 15 to form innumerable recesses 14. After that, the surface of the mat 1 is roughened, and the cement molding material 2 whose main component is hydraulic cement whose water content does not exceed 50% is sprayed on the surface of the mat 1. In this case, the water content of the mat 1 is 5%.
0 to 150%. The water content of the mat 1 is closely related to the spray thickness of the cement molding material 2, and it is preferable to increase the water content as the spray thickness increases. Incidentally, a part of the cement molding material 2 may be sprinkled on the mat 1 immediately after the papermaking, and the remaining cement molding material 2 may be sprinkled after the mat 1 is roughened.

The cement molding material 2 to be sprayed on the mat 1 is made of hydraulic cement and fibers such as vinylon and polypropylene.
Pulp, and if necessary, lightweight aggregates such as shirasu balloon and perlite are added, and the water content is 50%.
Adjusted to: For example, this molding material 2 is mixed by a dry mixer 4 as shown in FIG. Dry mixer 4
As such, an Eirich mixer, a high speed mixer or the like is used. Next, the wet mixer 6 by the constant quantity feeder 5
Is quantitatively supplied to the wet mixer 6, and water is added into the wet mixer 6 as indicated by an arrow. Water is 0 to 50% by weight based on the solid content of the cement molding material 2. The reason why the amount of water added varies is that it varies depending on the composition. That is, the lower limit of the amount of water added is a range in which dust is not generated when the cement molding material 2 is sprayed, and the upper limit is that the cement molding material 2 does not flow during pressurization to form a clean pressing surface such as an uneven pattern. Is the range that is prevented. The cement molding material 2 adjusted to a predetermined water content by the wet mixer 6 is supplied to the widthwise distribution device 8 by the material supply device 7. The cement molding material 2 substantially evenly distributed in the width direction (maximum width of 1600 mm) by the width direction distribution device 8 has a vibration feeder 9
Is evenly conditioned to be sprayed on the mat 1. In this case, when using the cement molding material 2 in which a large amount of fibers and the like are liable to become lumps, the cement molding material 2 is sprayed after passing through the disentangling machine 10. Further, if necessary, it is conditioned by a habituation machine 11 or pressed by a pressing roll 12 to perform preliminary pressing to prevent the cement molding material 2 from scattering during pressure molding.

In this way, after the cement molding material 2 is continuously sprayed on the mat 1, the upper mold 13a and the lower mold 13b are
The press machine 13 consisting of
After this, curing and curing is carried out to produce the inorganic cement board A. In this case, an uneven portion may be formed on the lower surface of the upper mold 13a, and an uneven pattern may be formed on the surface of the inorganic cement plate A.

For example, 48% by weight of cement, 30% by weight of fly ash, 15% by weight of lightweight aggregate, 2% by weight of fiber, 5% by weight of pulp, 2% of water on the mat 1 made by the Fourdrinier method.
A cement molding material containing 5% by weight of 2400 gr /
m ^{2 was} sprayed and pressed at a pressure of 30 kg / cm ² for 2 seconds, and then cured and cured to produce an inorganic cement board. This is a frost damage test (ASTM-A method, ASTM-
No interfacial peeling occurred when subjected to the B method, transmission test).

Further, a cement molding material 2 as shown in FIG.
By installing two or more spraying devices of No. 2, two or more layers of the cement molding material 2 are formed, and it is possible to manufacture an inorganic cement board A having three or more layers as a whole. Thus, according to the present invention, the conventional pattern depth is 2-3.
Although the limit was mm, it became possible to form uneven patterns deeper than that, and in the case of manufacturing thick products, if only papermaking is performed, the speed will decrease and the productivity will decrease significantly. However, the thickness can be secured by spraying the cement molding material, and a thick product can be manufactured without lowering the papermaking speed. In addition, since the moisture of the lower mat 1 moves to the upper cement molding material 2 during pressure molding, the water content as a whole becomes low, and the energy required for drying can be small. In addition, the rough surface of the mat 1 increases the degree of interfacial adhesion between the mat 1 and the cement molding material 2 and significantly improves frost damage resistance. Furthermore, it can be applied to a structure having three or more layers, A product can be manufactured.

[0012]

According to the present invention, the surface of the mat immediately after paper making is roughened, and a cement molding material whose main component is hydraulic cement having a water content of not more than 50% is sprinkled on the surface of the mat. Since it is pressure molded, it is possible to form a deep uneven pattern on the mat, and mechanical strength can be secured by the cement molding material. Furthermore, due to the anchor effect of the rough surface of the mat, the mat and cement molding material The interfacial adhesion is also increased and the frost damage resistance is significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic view showing a step of roughening a mat surface of the present invention.

FIG. 2 is a schematic view showing an apparatus for carrying out the step of spraying the cement molding material according to the present invention.

FIG. 3 is a schematic view showing an apparatus for carrying out a pressurizing step in the present invention.

4A and 4B are views showing a pressurizing step of the present invention, in which FIG. 4A is a view showing a state before pressurization and FIG. 4B is a view showing a state after pressurization.

[Explanation of symbols]

 A Inorganic cement board 1 Mat 2 Cement molding material

Claims (2)

[Claims] 1. A slurry containing hydraulic cement and water as main components is made by a papermaking method, and the surface of the mat immediately after the papermaking is roughened to obtain a hydraulic cement having a water content of not more than 50%. Disperse the cement molding material as the main component,
Next, a method for producing an inorganic cement board, which comprises press-molding and then curing and curing. 2. The method for producing an inorganic cement board according to claim 1, wherein the cement molding material is sprayed twice or more to form two or more layers of the cement molding material.