JP2000027358A - Cement board having irregular pattern and template for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight cement board having an irregular pattern and a fiber-reinforced plastic template for manufacturing the cement board. SOLUTION: The cement boards 9, in which surfaces have irregular patterns and rears have inverted irregular patterns approximately corresponding to the irregular patterns of the surfaces, are manufactured. The fiber-reinforced plastic templates 1, in which one surfaces have irregular patterns corresponding to irregular patterns 92 on the surface sides of the cement boards 9 of products and the other surfaces have irregular patterns inverted while corresponding to irregular patterns 91 on the rear sides, are used at that time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cement-based board having an irregular shaped pattern used for walls, floors, ceilings and the like inside and outside a building, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, demand for cement-based boards having an uneven pattern on the surface thereof has been increasing as interior and exterior materials of buildings such as houses due to the variety of surface designs.

[0003] In particular, cement-based boards having an uneven pattern with a deep groove and a three-dimensional appearance are luxurious and popular. However, since the surface unevenness pattern is formed on the substrate part with a certain thickness, such a three-dimensional unevenness of the cement-based board has a smaller depth than the cement-based board with a shallow groove and unevenness. The problem is that the weight increases, handling such as transportation and construction becomes difficult, and the load applied to the building attached as the interior / exterior material increases.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cement-based board having a light and uneven pattern not found in the prior art.

[0005]

That is, the present invention provides:
On the back side of the cement board with the required design unevenness pattern on the surface, by adopting a structure with the reverse unevenness pattern substantially corresponding to the surface unevenness pattern, by reducing the average thickness of the cement based board It is intended to reduce the weight.

[0006] Here, having the reverse uneven pattern substantially corresponding to the uneven pattern on the front surface means that the uneven pattern on the rear surface is formed such that the thickness of an arbitrary cross section of the board becomes substantially equal. When viewed from the macro side, when the front side is a convex part, the back side is a concave part, and when the front side is a concave part, the rear side is a convex part. Further, since the purpose is to reduce the weight, the reverse uneven pattern substantially corresponding to the uneven pattern on the front surface may cover not only the entire back surface but also the main part. Although it depends on the uneven pattern, in many cases, the range of the uneven pattern on the rear surface is 5% of the entire rear surface.
By occupying 0% or more, a weight reduction effect can be obtained.

In a conventional cement board, the uneven pattern on the surface is formed on a substrate portion having a certain thickness that can withstand rupture only by its thickness. Therefore, while using the same material as the substrate part, the convex part has a structure that does not contribute to the breaking strength. The present invention is intended to reduce the weight of the cement board by reducing the thickness of the substrate at the convex portion.

In a cement board, an uneven pattern having joints on its surface is often employed in design, but joints have a width of several mm to several tens of mm, and the depressions are generally deep and long. However, when an impact or external force is applied to this portion, the portion tends to be easily broken. For this reason, it is very important to ensure the breaking strength of the joint portion. The area of the joint portion occupying the entire surface is usually several percent, and although it is at most 20% or less, it is necessary to prevent breakage. The method of forming on a substrate part having a certain thickness has been followed.

In the present invention, an arbitrary cross section of the board is made substantially equal in thickness so that the board is hardly partially broken, and the average thickness is reduced to reduce the weight. Specifically, it is to adopt a structure having a reverse uneven pattern substantially corresponding to the uneven pattern on the surface on the back surface of the cement board having the uneven pattern on the surface. In order to maximize the weight reduction, it is preferable to adopt a concavo-convex pattern in which the thickness of an arbitrary cross section of the board is as infinite as possible, but from the practical viewpoint including the manufacturing cost, it is commensurate with the weight reduction effect. It is conceivable to adopt the idea of the present invention within the scope. For example, when the surface has an uneven pattern including joints, the joints have a large effect and are generally composed of long straight parts, so the pattern is easy to draw and machining such as cutting is easy, so molding In some cases, the template can be made cheaply, so it is conceivable to use it only for joints.

In order to manufacture a cement board having such an uneven pattern on the front side and a reverse uneven pattern on the back side substantially corresponding to the uneven pattern on the front side, it is necessary to use a cement-based board as a product on one side. A fiber reinforced plastic template having an uneven pattern corresponding to the uneven pattern on the front side, and having an uneven pattern corresponding to the uneven pattern on the back side of the cement board (that is, inverted from the front side) on the other surface. Prepare multiple sheets. A plurality of cement boards can be obtained at one time by arranging these plural templates in the order of front and back, front and back, and pouring cement between them to solidify. That is, using these templates, one of the templates is placed on the front side or the back side on the upper side, and a predetermined amount of the fiber-reinforced cement material is placed thereon.
With respect to the other template, the same surface is placed on the upper side, and a predetermined amount of the fiber-reinforced cement material is placed thereon. The fiber-reinforced cement material can be manufactured by heating and curing under pressure by a stacking press on which the loaded fiber-reinforced cement material is placed, followed by demolding and drying.

[0011] Of course, as described above, instead of a template having an uneven pattern on the front and back, a template having an uneven pattern on the front or back is combined. Can also produce the cement board of the present invention.

In the fiber reinforced plastic template used here, the use atmosphere repeatedly changes from room temperature to about 80 ° C., which is the heat curing temperature of cement.
Dimensional changes and warpage may occur. If these problems are important in manufacturing, a metal plate such as an iron plate or stainless steel may be interposed in order to prevent these problems. In this case, it is conceivable to bond a reinforced plastic layer to both sides of the metal plate. However, if the metal plate has a large number of openings such as a punching plate, grating or a wire mesh, the reinforced plastic layer may be bonded to the openings. Are connected to each other, and the bonding becomes stronger, which is preferable in preventing peeling. Further, when the metal plate is deviated to either the surface layer side or the back surface side of the reinforced plastic layer as viewed from the cross section of the template, the metal plate is preferably present at the center because the warp easily occurs. Further, it is more preferable in terms of balance to separately provide metal plates in contact with the surface layer side and the back side.

The fiber reinforced plastic having an uneven pattern on both the front and back surfaces as described above can also be manufactured by making each of the front and back surfaces having the uneven pattern by hand lay-up, and then laminating them. In addition, a metal plate can be sandwiched during bonding. Also RT
M (resin transfer molding method) and SMC
It can also be manufactured by a method using a mold such as (sheet molding compound method).
Further, as described in JP-B-7-12613, a surface layer portion composed of a thermosetting resin phase containing a fibrous reinforcing material, a core portion composed of the resin phase containing expanded particles, and the surface layer portion and It is also possible to use a method for producing an integrated composite molded article comprising a separated phase existing between the core and the core.

[0014]

According to the present invention, the cement-based board having a concave and convex pattern on the surface thereof has a reverse concave and convex pattern substantially corresponding to the concave and convex pattern on the front surface, thereby reducing the strength of the cement-based board without lowering the breaking strength. The weight can be reduced by reducing the average thickness of the board, and the cost can be reduced by reducing the amount of the raw material such as cement. Further, by using the template of the present invention, the cement board of the present invention can be manufactured efficiently.

[0015]

Next, an example of a method for manufacturing a cement board by the manufacturing method of the present invention will be described with reference to the drawings. As shown in FIG. 2, the template 1 used in this example is a fiber reinforced plastic template having an uneven pattern on the front surface and a reverse uneven pattern substantially corresponding to the surface uneven pattern on the back surface. Is sandwiched between them. As shown in FIG.
While placing and moving the template 1 (plurality) on a conveyor 3 with the front side facing upward, water and air flow from above,
A predetermined amount of a raw material 4 of fiber-reinforced cement in which fiber such as wood chips and cement are mixed is dropped on the template 1 and is loaded to a predetermined thickness. Next, the loaded mat-shaped raw material 4 is sequentially stacked on the carriage 5 together with the template 1 over several to several tens of stages, and a press machine 6 applies a pressure of 80 kg / cm 2 and tightens. The whole of the stacked bodies pressed together in the pressed state is fixed by operating a lock mechanism on the carriage 5 at a fixed height. Next, the laminated body in the pressed state is placed on a cart 5
Curing room 7 with an ambient temperature of 60 to 85 ° C.
Put in. From about half a day to one day, the raw material of the fiber reinforced cement, which is the content, becomes the cement board 9 by hardening by heating and self-heating. After that, the entire laminate is placed on the cart 5, taken out of the heat-retaining curing room, the locking mechanism of the cart 5 is released, the cement board and the template 1 are separated, and the cement board is placed on another cart 8. Drying room 10 stacked stepwise
It is put into the oven, dried, cut to the required dimensions, processed for edges, etc., and then painted on the surface side in the painting process to form a product.

In this way, as shown in FIG. 3, the pattern of the template 1 having the concave and convex pattern on the front surface and the reverse concave and convex pattern substantially corresponding to the concave and convex pattern on the front surface is transferred to both sides. A cement-based board is obtained.

In the same manner as in this embodiment, instead of a fiber-reinforced plastic template having an uneven pattern on the front surface and a reverse uneven pattern on the back surface substantially corresponding to the uneven pattern on the front surface, an uneven pattern is formed on the surface. By using a fiber reinforced plastic template having a smooth surface on the back side, a conventionally known cement board having an uneven pattern on the surface and no unevenness on the back surface can be obtained. The surface has a natural stone-like uneven pattern with joints, the back has no irregularities, length 3030 mm, width 45
The standard is a 5 mm wood fiber reinforced cement board having a joint section having the thinnest section thickness of 12 mm and a section having the most convex surface having a section thickness of 18 mm. A cement-based board having the same surface irregularities, a reverse irregularity pattern on the back surface substantially corresponding to the surface irregularity pattern, and using the same material as the standard having an average cross-sectional thickness of 13 mm is designated as A. A cement using the same material as the standard, having the same surface irregularities, having a pattern of convex portions of 3 mm height on the back surface substantially corresponding to the joints of the surface, and having a cross-section thickness of the most convex portion of 15 mm on the surface. The system board is B. Table 1 shows the results of measuring the weight and the bending fracture load after coating the surface with an acrylic emulsion in each case.

[0018]

[Table 1]

From Table 1, it can be seen that, as compared with the standard, both A and B can withstand the same bending fracture load as the standard despite the reduced weight.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a process in an embodiment of the present invention.

FIG. 2 is a sectional view of a template used in the embodiment.

FIG. 3 is a cross-sectional view of a dried cement-based board obtained in an example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 template 2 raw material supply device 3 conveyor 4 raw material 5 trolley with lock mechanism 6 press machine 7 insulation curing room 8 product trolley 9 cement board 10 drying room 11 surface (decorative) irregularity 12 back irregularity 13 metal plate 91 Uneven pattern on product back surface 92 Uneven pattern on product surface (decorative)

Claims (7)

[Claims] 1. A cement board having an uneven pattern on the front surface and a reverse uneven pattern on the back surface substantially corresponding to the uneven pattern on the front surface. 2. The cement board according to claim 1, wherein the range of the uneven pattern on the back surface occupies 50% or more of the entire back surface. 3. A cement board having a concavo-convex pattern including joints on the front surface and a convex pattern on the back surface substantially corresponding to the joints on the front surface. 4. The cement-based board according to claim 3, wherein the projections substantially corresponding to the joints on the front surface of the back surface are formed on the entire back surface.
A cement board characterized by being occupied by 0% or more. 5. A cement-based board having a cement-based board having a concavo-convex pattern including joints on its surface, wherein a thickness of a cross section at an arbitrary joint portion is equal to or greater than an average thickness of the entire concavo-convex pattern portion of the board. 6. A template used for producing the cement board according to claim 1, wherein the template has an uneven pattern corresponding to the uneven pattern on the surface side of the cement board on one surface thereof. A fiber-reinforced plastic template having an uneven pattern corresponding to the uneven pattern on the back side of the cement board on the other surface. 7. The fiber-reinforced plastic template according to claim 6, having a structure in which a metal plate is sandwiched inside.