JPH11114929A - Patterning method of fiber reinforced cement plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain a deeply engraved uneven pattern on the surface of a fiber reinforced cement plate without being limited by material by a method wherein the water content of an uncured fiber reinforced cement plate is prepared by spraying water on the air-included layer, which is obtained by loosing the surface of the uncured fiber reinforced cement plate and, after that, an uneven patterning pressing is applied to the surface of the cement plate and finally the resultant cement plate is hardened by curing. SOLUTION: A slurry A is supplied in a layer 3 having the thickness of 15-25 mm on an endless felt belt equipped with a suction dehydrating device 1 so as to be conveyed through suction dehydration in order to rotate a spike roll 4 on a cement layer 3 so as to pivotally support the tip portions of pins 4A in order to contact with the cement layer, resulting in loosing the surface of the cement layer 3 when the dehydration is realized to the extent that the free water on the cement layer 3 disappears. Water is uniformly supplied on the surface of the uncured cement layer 3, the surface of which is loosed, from a spray 7 so as to turn the water content of the loosed layer to be 50-60%. After that, the resultant cement layer is cut with a cutter 5 in sizes and transferred to a pressing device so as to be pressed with an unevenly patterned pressing platen 6A. After pressing, the formed plate material 3 is naturally cured for 24 hours.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for patterning a fiber reinforced cement board.

[0002]

2. Description of the Related Art Conventionally, fiber-reinforced cement boards have been widely used as building materials such as wall boards and roofing materials.

[0003] Many of these fiber reinforced cement boards are provided with an uneven pattern on the surface to impart a design, and press molding is often used as a method for forming the uneven pattern. By the way, it is known that the flowability of the surface of the uncured plate material at the time of pressing should be increased in order to form a deep uneven pattern by the press molding method.

[0004] For this reason, it has been customary to increase the water content to the bareest level that can be produced, and to apply an uneven pattern directly to the surface of the formed plate material by pressing the uneven surface directly.

[0005]

However, if the content of water is excessively increased as described above, the base material flows due to the pressure at the time of pressing, which causes a problem in the production of the plate material itself, or the dehydration at the time of pressing does not work well. However, there is a problem that a problem easily occurs.

[0006] That is, if the water content is large, depending on the pressing pressure, water running occurs in the structure and the surface of the uncured cement plate at the time of pressurization, and the inorganic particles contained in the structure are caused by the water running. There is a problem that outflow occurs, which causes cracks on the product surface and a decrease in design properties due to surface roughening.

On the other hand, by changing the amount of the reinforcing fibers contained in the structure of the fiber-reinforced cement board, the length of the fibers used, or the composition of the base material, the uncured fiber-reinforced cement before pressing is changed. Although the fluidity of the board has been improved, changes in the amount and length of the fibers used are directly related to the strength of the product, so it is impossible to make significant changes. The range in which the flowability can be improved was extremely limited because of the direct influence on the performance.

[0008] For this reason, the types of patterns and patterns that can be press-formed are limited, and there is a problem that it is particularly difficult to form a deeply carved uneven pattern by pressing. The present invention has been made for the purpose of solving the above problems,
The purpose of the present invention is to easily produce a deeply carved uneven pattern on the surface of a fiber-reinforced cement board without limitation of materials.

[0009]

According to a first aspect of the present invention, there is provided a method of patterning a fiber-reinforced cement board, wherein the surface of the uncured fiber-reinforced cement board is loosened to form an aeration layer, and water is sprayed on the surface of the layer to contain water content. After adjusting the surface roughness, the surface is subjected to an uneven pattern press, and then cured and cured by an ordinary method.

[0010] Here, the aerated layer means a layer in which the uncured fiber reinforced cement material on the surface of the fiber reinforced cement board is loosened, and the structure becomes coarse with air. This loosening means can be achieved by rotating and moving a spike roll in which pins are provided roughly on the outer periphery of the rotating drum in the radial direction while rotating and contacting the surface of the uncured fiber reinforced cement board, or by providing pins in the form of comb teeth. The slide bar is brought into contact with the surface of the uncured fiber reinforced cement board, and is continuously moved alternately in the axial direction and the direction perpendicular to the axial direction to roughen the surface with the pins.

The aeration layer thus formed has a high bulk and is a porous layer. Therefore, if water is sprayed on the surface of this layer, moisture easily penetrates the porous layer, and the water content of this layer increases.

For this reason, it is possible to press-form a deep uneven pattern. According to a second aspect of the present invention, in the method for patterning a fiber-reinforced cement board, the uncured depth of the surface of the uncured fiber-reinforced cement board according to the first embodiment is 60% to 15% of the unevenness of the press die.
0%.

This is for improving the reproducibility of the uneven pattern.
Here, the unraveling depth should be 60% to 1% of the unevenness of the press mold.
If the depth is less than 60%, the depth of the porous layer is not sufficient, so that the water supply by watering is insufficient, and there may be a case where the deep unevenness of the carving is not sufficiently provided.
When the depth is deeper, the texture of the substantial part of the plate material that does not reach the uneven pattern becomes coarse, the water supply depth by watering becomes too large, and the deeply carved uneven pattern is applied to the slurry with too much moisture as in the conventional technology This causes the same problem as described above.

[0014]

Next, an embodiment of the present invention will be described.
40% by weight cement, silica sand
40% by weight, 10% by weight of pearlite, and 10% by weight of pulp fiber having a fiber length of 2 to 4mm as pulp fibers are prepared in a commonly used cementitious composition. Cement slurry A having a concentration of 25% was prepared. Example 1 As shown in FIG. 1, a slurry A was supplied in a layer 3 having a thickness of 15 to 25 mm on an endless felt belt 2 provided with a suction dewatering device 1 and transported while suction dewatering was performed. When the spike roll 4 was dehydrated to the extent that disappears, the spike roll 4 was pivotally supported on the cement layer 3 so that the tip portion 3 mm of the pin 4A was in contact with the spike roll 4, and the surface of the cement layer 3 was loosened.
At this time, the water content of the cement layer 3 was 40 to 50%.

The spike roll 4 has a diameter of 50.
On the outer periphery of the drum having a length of 1 cm, a pin having a length of 1 cm was used to stand in an at random arrangement at a rate of one per 1 cm ² .
Water is evenly supplied to the surface of the uncured cement layer 3 whose surface has been loosened by the spray 7, and the water content of the loosened layer is reduced.
50-60%.

Incidentally, the moisture content of the layer of the spike roll which did not reach the pin 4A and was not loosened was almost the same as the moisture content described above. After that, it is cut by the cutter 5 and transferred to the press device 6, where the press plate 6A has a brick joint of 10 cm × 5 cm and has a depth d = 5 mm and a rising angle θ of the uneven pattern θ = 60 ° as shown in FIG. And compression-pressed at a pressure of 15 MPa for 60 seconds.

After pressing, the molded plate 3 was naturally cured for 24 hours, and then autoclaved at 170 ° C. for 15 hours to obtain a product. Example 2 A fiber-reinforced cement board product was obtained in the same manner as in Example 1, except that the contact depth of the spike roll 4 was 4 mm. [Example 3] A fiber reinforced cement board product was obtained in the same manner as in Example 1 except that the contact depth of the spike roll 4 was 5 mm. Example 4 A fiber-reinforced cement board product was obtained in the same manner as in Example 1 except that the contact depth of the spike roll 4 was 6 mm. [Comparative Example 1] A plate material was cut by a cutter 5 without contacting the spike roll 4, and thereafter, Example 1 was performed.
A fiber reinforced cement board product was obtained in the same manner as described above. Comparative Example 2 A fiber-reinforced cement board product was obtained in the same manner as in Example 1, except that the contact depth of the spike roll 4 was 2 mm. Comparative Example 3 A fiber-reinforced cement board product was obtained in the same manner as in Example 1, except that the contact depth of the spike roll 4 was 8 mm.

With respect to the above Examples and Comparative Examples, the water content of the uncured fiber-reinforced cement plate immediately before pressing, the appearance of surface irregularities after production as a product, and the bending strength were measured. Table 1 shows the results.

As is clear from Table 1, in Examples 1 to 4, the deeply carved uneven pattern was clearly provided, and almost no cracks around the uneven pattern were observed. On the other hand, in Comparative Example 1, an unclear portion such as a chip was found at the edge portion of the uneven pattern, and a number of cracks running along the edge were found on the convex pattern surface.

Comparative Example 2 was considerably better than Comparative Example 1, but showed unclear edges and cracks along the edges. In Comparative Example 3, there was no problem in terms of the uneven pattern and cracks, but the bending strength was lowered and it became difficult to use as a building material.

The bending strength in Table 1 is based on the JIS No. 4 bending test.

[0022]

[Table 1]

[0023]

As described above, according to the first aspect of the present invention, even if the water content at the time of making the fiber reinforced cement board becomes low, water is sprayed onto the porous surface by loosening to make the surface layer. Is increased, a deep uneven pattern can be provided with good reproducibility even if the water content of the main body portion is low.

Further, according to the invention of claim 2, there is an effect that a deep uneven pattern can be more reliably provided without affecting the substantial part of the fiber reinforced cement board.

[Brief description of the drawings]

FIG. 1 is a side view of an apparatus for performing a method according to the first aspect of the present invention.

FIG. 2 is an enlarged sectional view of a main part of a concavo-convex pattern type of a press machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Suction dehydration apparatus 2 Endless felt belt 3 Cement layer 4 Spike roll 5 Cutter 6 Press board 7 Spray

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Kazuyuki Komatsu 1-1-1 Hama, Amagasaki-shi, Hyogo Pref.

Claims (2)

[Claims] 1. An uncured fiber-reinforced cement board surface is loosened to form an aeration layer, and water is adjusted on the surface of the layer to adjust the water content. A patterning method for a fiber-reinforced cement board, which is cured and cured. 2. The unraveling depth of the surface of the uncured fiber reinforced cement board according to claim 1 is 60% or less of the depth of unevenness of the press die.
A method for patterning a fiber reinforced cement board, characterized in that it is 150%.