JPH0244080A - Production of inorganic building board - Google Patents

Abstract

PURPOSE:To render extremely superior water resistance to the title board and to surely prevent efflorescence from occurring by subjecting a molded body consisting of an inorg. blend for a base layer and thermoplastic resin powder to natural curing and curing at a high temp. CONSTITUTION:A base layer is formed with an inorg. blend contg. cement, silia and reinforcing fibers and a layer of a blend prepd. by adding 1-20wt.% thermoplastic resin powder to the inorg. blend is laminated on one side of the base layer in one body to form a board-shaped body. This body is naturally cured for about 24hr and cured at the melting temp. of the thermoplastic resin. Acrylic-styrene resin consisting of about 50% acrylic component and about 50% styrene component may be used as the thermoplastic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing an inorganic building board, and more particularly, to a method for manufacturing an inorganic building board with improved water absorption resistance.

[Prior art] Generally, inorganic building boards made of cement etc. as the main component, especially for flat roofs [e. It is necessary.

Therefore, in the past, it has been customary for such inorganic board materials to be coated with waterproof coatings in various colors, which also serves as surface decoration.

[Problems with conventional technology]

By the way, in the past, the waterproof layer was a surface coating film, and there is no historical record of this. Because it is not cooled down to °C,
Water absorption from the back side of the board, II! ＞? There is a problem in that Q causes upper flaring, which precipitates on the surface of the product and deteriorates the appearance of the product (T).

However, this problem can be solved by applying a waterproof coating to both the front and back sides of the board, but it is not easy to apply paint to the front and back sides of the board during the assembly process using Helt 21 Nhair. Reversing equipment: Requires a large amount of incidental equipment such as L paper towel rollers, making it difficult to implement.

[Problem to be solved by the invention]

In view of the above-mentioned problems, the present invention has been made with the object of providing a method for manufacturing a 15% Pl (structured construction board) that is easy to implement and exhibits reliable waterproof properties.

[Technology that led to solving the problem]

That is, in the method for manufacturing an inorganic building board of the present invention, one side of a base material layer made of an inorganic compound consisting of cement, silica, and necessary reinforcing fibers is coated with 1 to 20% of the inorganic compound for the base layer.
A plate-like body is formed by integrally laminating layers made of a blend containing thermoplastic resin powder of % by weight, and the formed body is naturally cured. The 111th characteristic is to carry out high temperature curing at the melting temperature of the powder.

[For 11] The inorganic compound of the base material layer used in this invention is:
Conventional and most commonly used cement formulations are applicable and are not particularly limited.

The layer laminated on this base layer is made by adding 1 to 20% by weight of thermoplastic resin powder to the base layer inorganic compound.

The thickness of this resin + 5) non-additive inorganic layer is 17 or less, which is sufficient for the base layer.

These layers can be formed by, for example, using a dry method to sequentially supply each compound onto a conveyor, or using a paper-making method to prepare raw material hats and sequentially paper-making these raw materials. , a method of stacking layers is adopted.

Then, if these laminated materials (Qa board materials are firstly cured by natural curing, and then cured at high temperature at the volume temperature of the thermoplastic resin powder), the added thermoplastic resin powder will melt and form within the cement matrix. It is immersed in water to transform it into a waterproof layer-like structure, and leaches onto the surface of the board to form a thin film layer, forming a complete waterproof layer.

After that, when it is cooled to room temperature, the piece 117 becomes a nearly complete waterproof layer.

``In two cases, the amount of the thermoplastic resin main 5) powder added to the base layer inorganic compound is 1 to 201]! Amount% and Zurono are
If it is less than 1%, the waterproof effect cannot be obtained, and 20%.
Even if the amount is increased, there will be no improvement in the waterproof effect (on the contrary, it will have an adverse effect on the strength).

The other surface of the molded plate (E) is coated with waterproof f4 before or after the secondary curing.

Therefore, a waterproof layer is formed on the front surface with the paint and on the back surface with the above-mentioned plastic coating.

〔Example〕

Next, the present invention will be explained in detail.

<Example 1> By dry method 19, 100% of this mixture
50% acrylic, 509% styrene
20wt 1% acrylic/styrene resin powder consisting of G
The added mixture was spread on a molding layer to a uniform thickness of about 51 mm, and then a cement mixture of about 7 mm was spread on the layer by a conventional method from L1iJ.
After supplying the necessary water with Hk heavy cloth, the material was rolled and compressed to a thickness of 5 m to form a plate material.

Next, the formed plate material was naturally cured at room temperature for 24 hours.

Thereafter, the layer consisting of the cement mixture is coated with an acrylic emulsion paint, and heated in an autoclave to a temperature at which the resin powder can be melted, i.e. 180'C.
High temperature and high pressure sudden air curing was performed under the conditions of XIo hours.

<Example 2> A plate material was molded in the same manner as in Example 1, except that the amount of the acrylic/styrene resin 1 powder added in Example 1 was changed to 7%.

<Example 3> A plate material was molded in the same manner as in Example I except that the amount of acrylic/styrene resin powder added in Example 1 was changed to 5%.

<Comparative Example> After natural curing of an inorganic board material formed by a conventional method, waterproof coating was applied to the surface, and high temperature and high pressure curing was performed.

The tentative +A obtained in Examples 1 to 3 and the comparative example above is 10
Cut L into cm, the coated surface except the back surface and the cut end surface were waterproof-sealed, and soaked in water [No. 1] for 24 hours to test the amount of water absorbed.The results are shown in the table below.

In addition, when looking at the appearance of Examples 1 to 3 and the comparative example, Examples 1 to 2 are the 1st U! As shown in J, it was confirmed that a thin film-like layer 2 of molten resin was formed on the back surface IA of the plate l, and in Example 3, such a layer was not observed.
The state of resin impregnation was confirmed in comparison with the comparative example. In addition, in the figure, 2 shows the surface coating layer of the board l, 11 shows the layer of the cement mixture made by a conventional method, and 12 shows the layer of the cement mix added with resin powder.

This method has various effects, such as being able to prevent the above problems and also using the same equipment as before by simply changing the distribution of raw materials, making it possible to use existing equipment and being economical.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view of a main part of an embodiment of the present invention. 〔effect]

Claims (1)

[Claims] (1) From a mixture in which 1 to 20% by weight of thermoplastic resin powder is added to the inorganic mixture for the base layer on one side of the base layer consisting of an inorganic mixture consisting of cement, silica, and necessary reinforcing fibers. The manufacturing of an inorganic building board, characterized in that the layers thereof are laminated together to form a plate-like body, the formed body is naturally cured, and then high-temperature curing is performed at the melting temperature of the thermoplastic resin powder. Method.