JPS61160242A - Light-weight inorganic building board material - 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] Industrial applications This invention relates to lightweight inorganic construction board materials.

BACKGROUND OF THE INVENTION Conventionally, in order to reduce the weight of inorganic building materials, foamed concrete has been widely used as inorganic building materials.

These inorganic building materials whose weight has been reduced by foaming have a significantly lower apparent specific gravity due to the air bubbles contained inside, and it is said that it is possible to manufacture materials with a specific gravity of 1 or less.

However, these foamed inorganic building materials have the problem of condensation, such as a decrease in compressive strength and bending strength as the amount of air they contain increases. The problem was that it was difficult to reduce the weight of.

Furthermore, these lightweight inorganic boards have extremely low strength against local stress on the board surface, and the surface easily caves in and bends even with a light impact. There are problems in that the compost must be handled with care or must be packaged in strict packaging to prevent such accidents.

In addition, this type of foamed inorganic building material has a porous structure that easily absorbs water, so in order to solve this problem, for example, the air entrainment agent used for foaming is made of a water-repellent material. Alternatively, a waterproof layer is provided on the surface of the foamed inorganic building material, but this has the opposite effect,
The water absorption properties of building materials were lost, which could cause condensation when used as interior walls of buildings.

Problems to be Solved by the Invention In view of the above-mentioned problems, the present invention has been made for the purpose of obtaining a lightweight inorganic building board material that has strength and appropriate water absorption properties without impairing the lightness etc. of conventional foamed inorganic building materials. It is something that

The technology that solved the problem, that is, the lightweight inorganic building board material of this invention has a three-layer structure, the center layer is a foamed inorganic layer with a specific gravity of 1 or less and a high expansion ratio, and the surface layer is a foamed inorganic layer with a specific gravity of 1 or more. The non-foamed inorganic layer and the back layer are highly hygroscopic inorganic layers, and each layer is integrally laminated and fused.

Example This invention will be explained below with reference to Examples.

FIG. 1 is a sectional view of an embodiment of the invention.

The lightweight inorganic building board material A of the present invention has a three-layer structure, in which the center layer 1 is a foamed inorganic layer with a specific gravity of 1 or less and a high expansion ratio, and the surface layer 2 is a non-foamed inorganic layer with a specific gravity of 1 or more. The back layer 3 is a highly hygroscopic inorganic layer with a specific gravity of 1 or more, and the layers 1, 2, and 3 are integrally laminated and fused.

In the above, the center layer l is made of, for example, a mixture of cement, lightweight aggregate, an air entraining agent, and water and foamed to a high magnification. In addition, an acrylic air entraining agent prepared by adding asphalt to an acrylic ultrafine particle emulsion, or a mixture of this acrylic air entraining agent and a resinate air entraining agent is preferably used.

Among the air entraining agents mentioned above, the former generates a large number of microbubbles and can reduce weight and maintain strength, which has never been seen before, while the latter can generate microbubbles and maintain strength. Due to the synergistic effect of the air-entraining agent, which has the function of producing relatively large-diameter air bubbles, even greater weight reduction can be achieved.

Further, although the above-mentioned lightweight foamed aggregate is not necessarily required, pellet-shaped inorganic foamed aggregate obtained by firing expanded shale at a high temperature is suitable for use.

Since this central layer 1 is a layer that contributes to the weight reduction of the entire plate material, it is desirable that its specific gravity is as small as possible, and the specific gravity is at least 1 or less, preferably about 0.8.

Note that such a reduction in specific gravity is possible by using the above-mentioned acrylic air entraining agent or a combination of an acrylic air entraining agent and a resinate air entraining agent.

The surface layer 2 covers the surface of the surface layer 1 and functions as a strength reinforcing layer and a waterproof layer for the foam layer 10, and therefore,
It is a high-density cement layer made of cement, fine aggregate, reinforcing paper fibers, etc., or a resin concrete layer.

Note that this surface layer 2 may be a colored layer to which a colored pigment is added. Since this surface layer 2 mainly functions as a reinforcing layer, its specific gravity should be 1 or more for strength reasons, but the layer thickness should be as thin as possible so as not to impair the lightness of the entire board. This is desirable, and preferably about 20% or less of the entire board.

The back layer 3 is located on the back side of the center layer 1 and provides the building board with hygroscopic properties, and is made to have hygroscopic properties by adding pulp fibers, perlite, etc., for example.

Further, like the surface layer 2, this back layer 3 may also be a colored layer to which a colored pigment or the like is added, and in order to reduce the weight of the plate material, it is desirable that the thickness of the back layer 3 be about 20% of the total layer thickness.

In manufacturing the above-mentioned lightweight inorganic construction board A, first, cement slurry constituting the surface layer is injected into a formwork to a certain thickness, and then highly foamed cement slurry to which an air-entraining agent has been added is poured into the above-mentioned cement slurry. Pour onto the slurry,
Next, the cement slurry constituting the hygroscopic back layer is injected onto it, left as it is, and allowed to cure and harden.

Therefore, the three layers are laminated and fused together with their interfaces indistinct, and problems such as delamination do not occur.

In the above explanation, the cement slurry is sequentially injected into one mold, but a conveyor is constructed by connecting a large number of molds, and the cement slurry is injected into each mold while being transferred by this conveyor. Continuous production is also possible by a process of injecting into the frame.

In addition, in order to impart strength to the above-mentioned lightweight inorganic building board material, each layer is
．． The reinforcing reinforcing bars 4 may be embedded in either layer 2.3, or as shown in FIG. Also good.

Effects Since this invention is constructed as described above, by increasing the thickness of the center layer, the weight of the entire plate material can be reduced,
In addition, the surface layer ensures the surface strength of the foamed inorganic layer that makes up the center layer, making it easier to handle during storage or transportation, and the back layer is highly water-absorbent. This allows condensation water to be absorbed and prevents indoor walls from getting unduly wet.Furthermore, the front and back layers can be colored as desired, so they can be used as interior and exterior panels without any special surface painting. It is very useful as a prefabricated building material.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIGS.
B) and (C) are sectional views of other embodiments, and FIG. 3 is a fragmentary perspective view of essential parts of the other embodiment.

Claims (4)

[Claims] (1) It has a three-layer structure, the center layer is a foamed inorganic layer with a specific gravity of 1 or less and a high expansion ratio, the surface layer is an unfoamed inorganic layer with a specific gravity of 1 or more, and the back layer is an inorganic layer with high hygroscopicity. A lightweight inorganic construction board material characterized by each layer being integrally laminated and fused. (2) The lightweight inorganic board material according to claim 1, wherein the surface layer is colored. (3) The lightweight inorganic plate material according to claim 1 or 2, wherein the surface layer is a low water absorption layer. (4) The lightweight inorganic plate material according to claim 1, 2, or 3, wherein the back layer is a foam layer.