JP2983052B2 - Manufacturing method of noncombustible board for building - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a noncombustible board for building.

[Related Art] Cement-based sizing materials are used as architectural boards that can perform cutting and stapling in the same manner as ordinary wood and have excellent nonflammability. As a method for producing such a sizing material, a method of preparing a slurry-like raw material containing cement, reinforcing fiber, and water, supplying the raw material to a water-based support, forming a ribbon, and dehydrating and curing the ribbon under reduced pressure. It has been known. In addition, a method is also known in which the ribbon is dewatered under reduced pressure in the above step, and then a desired uneven pattern is formed on the surface by a roll press, and this is cured.

However, in such a method, it is difficult to obtain a board having excellent surface smoothness, and when forming a concavo-convex pattern on the surface by a roll press, it is difficult to form a pattern having a depth of 3 mm or more, and it is difficult to form a corner of a convex portion. However, there is a problem that it is difficult to form the shape and cracks are easily generated there.

[Problems to be Solved by the Invention] The present invention solves the above-mentioned problems of the prior art, has excellent surface smoothness, can form a deep pattern, and can easily form corner shapes of convex portions, An object of the present invention is to provide a method for producing a non-combustible board for building in which cracks are less likely to occur.

[Means for Solving the Problems] The present invention prepares a slurry-like raw material containing cement, reinforcing fiber and water, and continuously supplies the raw material onto a water-based support to form a ribbon. In order to continuously produce noncombustible boards by decompression dehydration from below the body, decompression dehydration is carried out with a substantially non-permeable sheet placed on the upper surface of the ribbon on the support. A method for manufacturing a board is provided.

In the present invention, the raw materials used include cement, reinforcing fibers, and water. As the cement, various cements including Portland cement are used, and among them, Portland cement is preferred because it is easily available and inexpensive. As the reinforcing fiber, asbestos, glass fiber, pulp, synthetic fiber and the like may be used alone or in combination of two or more.

Such a raw material may contain calcium silicate other than gypsum, slag, and cement as a property improving component, such as zonotolite.

Water is added to and mixed with the solid content to prepare a slurry-like raw material. The amount of water can be selected in consideration of the ease of handling and the like, but specifically, about 200 to 600 parts by weight per 100 parts by weight of solid content is practical.

In the present invention, a sheet having substantially no air permeability is used as the sheet placed on the upper surface of the ribbon. And what has moderate flexibility and rigidity is preferable. It is difficult to achieve the object of the present invention if it has air permeability, and specifically, air permeability of 0.1 cc / min · cm ² or less is preferable. As the flexibility, a material that can have a radius of curvature of 100 mm or less is preferable. The following rigidity is preferable. That is, in the case of stainless steel plate, 0.1 mm or more, in the case of hard vinyl chloride
The thickness is preferably 0.2 mm or more and 2 mm or more in the case of a soft rubber containing a reinforcing material.

Further, when forming an uneven surface on the board surface, it is preferable to form the unevenness corresponding to the sheet surface in contact with the ribbon. In this case, it is preferable to use a sheet having higher rigidity than the above. Specifically, a soft rubber containing a reinforcing material having a rigidity of 4 mm or more is preferable.

 The above is described based on the drawings.

FIG. 1 is a side view of an apparatus for carrying out the present invention, and FIG. 2 is a side view of another apparatus for carrying out the present invention. In the figure, 1 is a supply section of a slurry raw material, 2 is a filter cloth conveyor, 13 is a press roll, and 7 is a forming sheet.

As shown in the figure, a filter cloth conveyor 2 having water permeability is provided below the raw material supply section 1 and is circulated by a plurality of rollers 3 in the direction of the arrow. Below the filter cloth conveyor, a plurality of dewatering boxes 4 are provided in series, and are circulated by rollers 5 at a speed synchronized with the filter cloth conveyor. The slurry-like raw material supplied from the raw material supply unit 1 onto the filter cloth conveyor is transferred rightward and formed into a ribbon having a predetermined thickness by the doctor roll 6. Next, the ribbon is transported rightward, and the forming sheet 7 is placed on the upper surface thereof. The forming sheet has an endless shape, and is circulated by rolls 8, 9, 10, and 11 at a speed synchronized with the transfer speed of the ribbon. As such a forming sheet, a sheet having substantially no air permeability as described above is used. And what has moderate flexibility is preferable.

Below the dehydration box, a header 12 having one end connected to a vacuum pump is provided. The ribbon is sucked by a vacuum pump at a position on the left side of the roll 8 and a forming member is placed in a state where moisture in the ribbon has been removed to some extent. After passing through the roll 8, the ribbon is sucked through the dewatering box, whereby the forming sheet is pressed against the upper surface of the ribbon. Below the roll 8 on which the forming sheet is placed, the ribbon still contains a relatively large amount of water (for example, 100 to 600 parts by weight of water with respect to 100 parts by weight of solids) and is relatively weak. Is accurately transcribed. Then, the ribbon is transported rightward while being pressed by the forming sheet, during which dehydration proceeds and curing proceeds. Therefore, when the surface of the forming sheet that contacts the ribbon is excellent in smoothness, a ribbon having an excellent surface smoothness is obtained, and when the uneven surface is formed on the surface of the forming sheet that contacts the ribbon. Is transferred exactly to the ribbon.

The ribbon is transferred to the position of the roll 9 (the ribbon here is, for example, 40 to 60 parts by weight of water for 100 parts by weight of solid content),
The forming sheet is removed from the upper surface, and press forming is completed by the press roll 13. This press roll
13 is not always necessary, but it is desirable to provide it when manufacturing a ribbon with a smooth surface, because the smoothness can be further improved.

Next, the ribbon 14 is transported to the right and taken out of the filter cloth conveyor in a state where the pattern on the surface is hardened so as not to be substantially deformed. Next, although not shown in the drawings, the ribbon is cut to a predetermined size and completely cured.

2 is the same as that shown in FIG. 1 except that a press roll 13 is provided on the upstream side (from the left in the drawing) and the ribbon is pressed through a forming sheet.

Example An experiment was conducted using the apparatus shown in FIG. The raw materials used are as follows.

Cement 40 parts by weight Slag 45 parts by weight Perlite 10 parts by weight Pulp 7 parts by weight Water 300 to 400 parts by weight per 100 parts by weight of solids 3 m of slurry raw material with the above composition to a thickness of 25 mm
The ribbon was supplied to a m-thick felt endless belt to form a ribbon, and dewatered under reduced pressure at 350 to 450 mmHg from below. On the other hand, an accurate uneven pattern was transferred to the upper surface of the ribbon.

[Effect of the Invention] According to the present invention, a board having a surface excellent in smoothness and an accurate uneven pattern is manufactured. In particular, it is possible to easily form a deep uneven pattern and a pattern that does not cause roundness in the uneven portion, which has been extremely difficult in the past, and to manufacture a pattern having no crack in the convex portion.

[Brief description of the drawings]

FIG. 1 is a side view of an apparatus for carrying out the present invention. FIG. 2 is a side view of another apparatus for practicing the present invention. 1 Raw material supply unit 2 Filter cloth conveyor 4 Dehydration box 7 Forming sheet 14 Ribbon

Claims (2)

(57) [Claims] 1. A slurry-like raw material containing cement, reinforcing fibers and water is prepared, and the raw material is continuously supplied on a water-based support to form a ribbon. A method for producing a non-combustible board for construction, comprising continuously dehydrating a non-combustible board under reduced pressure with a substantially air-impermeable sheet placed on an upper surface of a ribbon on a support. 2. The method for manufacturing a non-combustible board for building according to claim 1, wherein the roll press is performed from the upper surface of the substantially air-impermeable sheet placed on the upper surface of the ribbon.