JP3216862B2 - Manufacturing method of inorganic plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an inorganic plate, in which a fiber-reinforced inorganic plate is produced from a slurry prepared by mixing reinforcing fibers and a hydraulic substance with water by a papermaking method. is there.

[0002]

2. Description of the Related Art Hitherto, in the case of manufacturing a thick inorganic plate by a papermaking method, a multilayer papermaking method in which a plurality of cake layers are laminated using a making roll has been adopted. However, since the production efficiency of this multilayer papermaking method is poor, in recent years, in order to improve the production efficiency, a method of manufacturing a thick inorganic plate using a cylindrical rotating body as shown in JP-A-57-39297. Is considered. In this method, as shown in FIG. 5, a slurry 11 made by mixing reinforcing fibers and a hydraulic substance with water is stored in a first storage tank 12, and a cylindrical filter cloth 13 over an endless belt-shaped filter cloth 13 is laid. While the rotating body 14 is immersed in the slurry 11 in the first storage tank 12 and rotated, the inside of the cylindrical rotating body 14 is decompressed to thereby obtain the slurry 1.
In 1, the cake layer 15 is adsorbed on the surface of the filter cloth 13. Further, a second storage tank 16 is disposed above the cylindrical rotating body 14, and the filter cloth 13 is arranged along the bottom opening of the second storage tank 16.
, The slurry 17 stored in the second storage tank 16 is gradually removed from the cake layer 15 on the filter cloth 13.
While increasing the thickness of the cake layer 15 from the lower surface of the filter cloth 13 with the suction box 18.
5 is vacuum-dehydrated to form a thick cake layer 15.

[0003]

In the above-mentioned paper making apparatus, the flexible piece 19 provided at the lower end of the second storage tank 16 is provided in order to prevent the slurry 17 from leaking from the bottom opening of the second storage tank 16. The (seal member) is brought into contact with the cake layer 15 on the filter cloth 13. In this configuration, it is necessary to smooth the surface of the cake layer 15 in order to maintain the sealing property between the flexible piece 19 and the cake layer 15.
Just before the flexible piece 19, the cake layer 1 is
5 is scraped off to make the surface of the cake layer 15 smooth. For this reason, the shavings shaved off by the brush roll 20 are not dispersed in the slurry 17 but re-agglomerated and adsorbed on the surface of the subsequent cake layer 15, and the surface of the cake layer 15 becomes uneven. There is a disadvantage that the vicious cycle is repeated and the quality of the inorganic plate to be manufactured is reduced.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for manufacturing an inorganic plate capable of efficiently manufacturing a high-quality thick-ground fiber-reinforced inorganic plate. is there.

[0005]

According to a first aspect of the present invention, there is provided a method for manufacturing an inorganic plate, comprising: mixing a reinforcing fiber and a hydraulic material with water; By storing and rotating the cylindrical rotating body wrapped with the endless belt-shaped filter cloth in the slurry in the storage tank and rotating it, the pressure of the cylindrical rotating body is reduced, whereby the filter cloth in the slurry is removed. In a method of adsorbing a cake layer on the surface, dewatering and press-forming the cake-like material to produce an inorganic plate for building, the upper surface of the filter cloth is stretched substantially horizontally, and the cake-like material adsorbed to the filter cloth is stretched. Along with transporting the material in a substantially horizontal direction, the cylindrical rotating body is provided with an adsorption area for adsorbing the cake layer in the slurry, and a dehydration area for dewatering the cake layer that has escaped upward from the surface of the slurry. Divided into A separate decompression device is connected to the region via a rotary valve, the suction performance is increased by increasing the degree of vacuum in the adsorption region, and the pressure can be reduced by a large suction air volume in the dehydration region, and from above the dehydration region. The surface layer molding material is sprayed on the surface of the cake layer adsorbed on the filter cloth.

In this case, the cylindrical rotating body is divided into four regions at 90 ° pitches, and
One area is the adsorption area, the area where the upper filter cloth contacts is the dehydration area, and the remaining one to which the filter cloth separates is
It is preferable that one of the regions is a region that is not decompressed.

Further, as a third aspect of the present invention, a slurry containing a coloring pigment may be used as a surface layer molding material that is sprayed on the surface of the cake layer from above the dewatering region.

According to a fourth aspect of the present invention, as the surface layer molding material, a powder molding material in which a hydraulic powder is a main component and reinforcing fibers are dry-mixed, or a resin emulsion is added to the powder molding material. A material may be used.

[0009]

According to the first aspect, the cylindrical rotating body on which the filter cloth is wrapped is dewatered into an adsorption area where the cake layer is adsorbed in the slurry and a cake layer which has escaped upward from the liquid level of the slurry. It is divided into a dehydration area, and a separate decompression device is connected to each area via a rotary valve. Thereby, in the adsorption area, the degree of vacuum is increased to enhance the adsorption performance, the thick cake layer is adsorbed on the filter cloth, and in the dehydration area, the decompression performance is increased by reducing the pressure with a large suction air volume. Then, the surface layer molding material is sprayed on the surface of the cake layer adsorbed on the filter cloth from above the dewatering area. As a result, the surface layer molding material is deposited in the depressions such as cracks on the cake layer surface, filling the depressions, and the surface layer and the cake layer (substrate layer) are firmly bonded by the surface layer molding material deposited in the depressions. Can be joined.

[0010] According to a second aspect of the present invention, the cylindrical rotating body is 90
The filter cloth is divided into four regions at a pitch of °, and the region where the filter cloth separates is defined as a region where the pressure is not reduced. This eliminates the need for the filter cloth to be adsorbed to the cylindrical rotating body in the area, allows the filter cloth to be drawn straight straight from the upper end of the peripheral surface of the cylindrical rotating body, and avoids unnecessary decompression, thereby improving efficiency. Good decompression (adsorption / dehydration) becomes possible.

According to a third aspect of the present invention, a slurry to which a coloring pigment is added is used as a surface layer molding material, and the slurry is sprayed or poured from above the dewatering area onto the surface of the cake layer. This makes it possible to apply colored makeup to the cake layer surface with the colored pigment.

According to a fourth aspect of the present invention, as the surface layer molding material, a powder molding material obtained by mixing a hydraulic powder as a main component and reinforcing fibers in a dry manner or a material obtained by adding a resin emulsion to the powder molding material is used. This is sprinkled on the cake layer surface from above the dewatering area and sprayed. In this case, the sprayed powder molding material absorbs the moisture in the cake layer, lowers the water content of the cake layer, and improves the production efficiency. Also,
If the resin emulsion is sprayed, the surface layer can be coated with the resin to increase the vertical tensile strength.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the construction of a papermaking apparatus used in Embodiment 1 will be described with reference to FIGS. Endless belt-shaped filter cloth 2
1 is wound around a large-diameter cylindrical rotating body 25 via a driving roller 22, a backup roller 23, and a plurality of tension rollers 24 and 34. The filter cloth 21 travels in a substantially horizontal direction from the upper end of the peripheral surface of the cylindrical rotating body 25 toward the drive roller 22, and conveys the mat-like cake 26 formed by the filter cloth 21 in the horizontal direction. Has become. Further, the filter cloth 2 extending from the driving roller 22 to the cylindrical rotating body 25 is formed.
A shower cleaning device 27 and a cleaning tank 28 for cleaning the filter cloth 21 and a meandering correction device 29 for correcting the meandering of the filter cloth 21 are provided in the travel path 1.

On the other hand, the lower part of the cylindrical rotating body 25 is immersed in the slurry 31 stored in the storage tank 30. The supply of the slurry 31 to the storage tank 30 is performed by the storage tank 30.
Through an inlet 32 formed in the upper part of the container. At the bottom of the storage tank 30, a plurality of agitators 33 are provided for agitating and uniformizing the slurry 31.

As shown in FIG. 2, the cylindrical rotating body 25 is
Divided into four areas at 90 ° pitch,
Sinks below the liquid surface of the slurry 31 to form an adsorption area. The filter cloth 21 wrapped around the cylindrical rotary body 25 is tensioned by a tension roller 34 so as to be in close contact with the suction area. On the other hand, the region is located at a level higher than the liquid level of the slurry 41, the region is a dewatering region, and the region is a non-decompression region.

A plurality of suction pipes (not shown) for applying a suction force to the outer peripheral surface of the cylindrical rotating body 25 are radially provided at a rotary valve 35 provided at the center of the cylindrical rotating body 25. ing. The suction area of the cylindrical rotating body 25 is connected to a vacuum pump (decompression device) (not shown) via a rotary valve 35, and the degree of vacuum is increased to, for example, about 0.6 to 0.7 kg / cm ^2, so that the suction performance is improved. And the thick cloth cake layer 36 can be adsorbed to the filter cloth 21. In addition, the dehydration region is a rotary valve 35.
Is connected to a high-pressure blower (decompression device), not shown, so that dehydration can be performed with a large suction air volume. On the other hand, in the non-decompression region, the pressure is not reduced. Therefore, in this non-decompression region, the filter cloth 21 does not have to be adsorbed on the cylindrical rotating body 25, and the filter cloth 21
Can be drawn straight out smoothly.

Further, above the dewatering area, there is provided a wet pouring device 38 for pouring the slurry 37 containing the surface layer forming material into the surface of the cake layer 36 little by little and spraying it. The amount of the slurry 37 sprayed by the wet pouring device 38 is adjusted by a flow rate adjusting gate 39. FIG.
As shown in the figure, a plurality of suction boxes 40 are provided on the lower surface side of the filter cloth 21 for conveying the mat-like cake 26 adsorbed and dehydrated by the cylindrical rotating body 25. The mat-like cake 26 is dehydrated under reduced pressure by evacuating with a pump (not shown).

The filter cloth 2 having passed through the suction box 40
A roller pressing machine 41 and a high-pressure water jet type cutter 42 are provided on the upper side of 1. The roller pressing machine 41 is a mat-like cake-like material 2 dehydrated in the suction box 40.
The surface of the cake 26 is flattened while pressing and dehydrating 6 from above. The cutter 42 cuts the mat-like cake-like material 26 having passed through the roller pressing machine 41 at a fixed length, and cuts the cake-like material 26 by jetting high-pressure water from a nozzle (not shown). I do. At this time, the nozzle is moved obliquely across the cake 26 conveyed to the mat conveyor 43, whereby the cake 26 is cut at a substantially right angle to the conveyance direction.

The following Table 1 shows the compositions of the slurry 31 (base material) and the slurry 37 (surface layer forming material) in Examples 1 to 4, and the evaluation results of the physical properties and surface condition of the produced inorganic plate. Things. The manufacturing methods of Examples 1 to 4 are the same except for the surface layer forming method.

[0020]

[Table 1]

The surface layer forming method of the first embodiment is a wet pouring method performed by using the wet pouring device 38 shown in FIG. The surface layer forming method of Example 2 is a wet spraying method in which a slurry is sprayed by a spray device or the like. On the other hand, the surface layer forming method of Examples 3 and 4 is a dry spraying method performed using dry spraying devices 44 and 45 shown in FIG.

As shown in Table 1 above, the slurries 31 (base material) used in Examples 1 to 4 have the same composition.
Mix hydraulic material, reinforcing fiber, lightweight aggregate and water,
The slurry has a solid content of 7 to 15% by weight, and a coagulant, a waterproofing agent and the like may be added as necessary. Here, examples of the hydraulic material include Portland cement, blast furnace cement, fly ash cement, silica cement, and alumina cement, and blast furnace slag, slaked lime, and quicklime may be mixed as necessary.
The reinforcing fibers include wood pulp, wood fiber, cotton,
Wood fibers from waste paper, organic synthetic fibers such as polypropylene, acrylic, vinylon, and nylon, and inorganic fibers such as glass, ceramic, and carbon may be used. As the lightweight aggregate, fine silica powder, lightweight pearlite, fly ash, shirasu burn, or the like may be used.

In Examples 1 to 4, the slurry 31 containing the base material shown in Table 1 was stored in the storage layer 30, and the filter cloth 21 was rotated integrally with the cylindrical rotating body 25. The pressure in the adsorption area is reduced to, for example, about 0.6 to 0.7 kg / cm ² by a vacuum pump (not shown), and the cake layer 36 is adsorbed on the filter cloth 21 running in the slurry 31. Then, in the dewatering region, a large suction air amount that can sufficiently dewater the cake layer 36 is applied to the high-pressure blower (see FIG. 3) even if there is an amount of air that leaks from cracks caused by volume contraction of the cake layer 36 that escapes from the liquid surface of the slurry 31. (Not shown), and the cake layer 36 is dehydrated under reduced pressure.

On the other hand, in the upper part of the dehydration area,
In step 4, the surface layer molding material is sprayed in different ways. As shown in Table 1 above, the surface layer molding material (slurry 37) used in each of Examples 1 to 4 includes cement, slag, pearlite, coloring pigment, pulp fiber, broken and crushed products, and the like. In Example 1, the slurry 37 of the surface layer molding material was used.
Is poured little by little from the wet pouring device 38 onto the surface of the cake layer 36 and sprayed at a rate of, for example, 1.5 to 2.0 kg / m ² . No resin emulsion was added to the slurry 37.

The surface layer forming method of the second embodiment is a wet spraying method in which a slurry is sprayed by a spray device or the like. The slurry used 2 more cement than the slurry 37 of Example 1.
A slurry containing 2% by weight of a resin emulsion mixed with a smaller amount by weight of a resin emulsion is used.
Spray at a rate of 7 kg / m ² .

On the other hand, the surface layer forming method of Examples 3 and 4 is as follows.
This is a dry spraying method performed using the dry spraying devices 44 and 45 shown in FIG. 3 or FIG. The dry spraying device 44 in FIG. 3 supplies the powder molding material into the vibrating sieve 48 by the charging conveyor 47 and, for example, 1.8 Kg of the powder molding material onto the cake layer 36 from the sieve net on the bottom surface of the vibrating sieve 48. Sprinkle at a rate of / m ² . On the other hand, the dry spraying device 45 of FIG. 3 disperses the powder molding material supplied into the box 50 by the charging conveyor 49 by the wind blown from the blower 51,
Sprinkle on the cake layer 36 at a rate of, for example, 1.8 kg / m ² .

The third and fourth embodiments may use either of the dry spraying apparatuses 44 and 45 shown in FIG. 3 or FIG.
Example 4 is an example in which a resin emulsion is not sprayed.
This is an example in which 2% by weight of a resin emulsion is sprayed with a dedicated nozzle or the like after the powder molding material is sprayed.

In each of Examples 1 to 4, the mat-like cake-like material 2 on which the powder molding material (slurry 37) was sprayed was used.
6 is dewatered under reduced pressure from the lower surface side of the filter cloth 21 by a plurality of suction boxes 40, and the surface of the cake 26 is flattened while the cake 26 is pressed and dewatered from above by a roller pressing machine 41. Thereafter, the cake-like material 26 is cut into a fixed length by the high-pressure water jet type cutter 42 and is conveyed to the mat conveyor 43. The cut cake-like material 26 is conveyed to a press (not shown) by the mat conveyor 43, pressed by a template and dewatered, and an uneven pattern is formed on the surface. Subsequent steps such as curing, curing, and drying may be performed by the same method as in the related art.

The data of physical properties measured for the inorganic plates manufactured in Examples 1 to 4 described above are shown in Table 1 above, and the data of physical properties of Comparative Examples 1 to 3 are shown in Table 2 below.

[0030]

[Table 2]

Comparative Example 1 is an example in which the surface layer molding material is not sprayed, and is otherwise the same as the above-mentioned Example. Also,
Comparative Example 2 is an example of a conventional multilayer papermaking method using a making roll, and Comparative Example 3 is an example of a casting method in which a slurry is injected into a mold and pressed.

Comparing the physical property data in Tables 1 and 2, Examples 1 to 4 show that both the vertical tensile strength and the freezing and thawing performance are the same as those of Comparative Example 1.
As compared with the case of No. 3 to 3, it is possible to stably form a high-quality uneven pattern. In the multilayer papermaking method of Comparative Example 2, the flexural strength is higher than that of Examples 1 to 4, but the vertical tensile strength is weak, and hair cracks occur when press-forming an uneven pattern on the surface of the inorganic plate. It is not suitable for forming a deep uneven pattern. Further, the casting method of Comparative Example 3 can form a concave-convex pattern with deep irregularities, but has disadvantages of low production efficiency and high cost.

On the other hand, in Examples 1 to 4, since the adsorption and dehydration of the cake layer 36 can be continuously performed using the cylindrical rotating body 25, the multilayer papermaking method (Comparative Example 2) and the injection Compared with the die method (Comparative Example 3), the production efficiency is better, cost reduction due to mass production effect can be expected, the installation space of the papermaking apparatus can be reduced, and the demand for space saving can be satisfied. In addition, since the surface layer molding material is sprayed on the cake layer 36 adsorbed and dehydrated as described above, the surface layer molding material is deposited in a concave portion such as a crack on the surface of the cake layer 36 and fills the concave portion. At the same time, the surface layer and the cake layer 36 (base layer) can be firmly joined by the surface layer molding material deposited in the concave portions, and a deep uneven pattern can be formed while improving the vertical tensile strength and the freeze-thaw performance. It was possible to stably mold, and the evaluation results of the surface state were good. In particular, in Examples 2 and 4, the resin emulsion is sprayed on the surface layer, so that the surface layer can be coated with the resin, and the vertical tensile strength can be further improved.

Moreover, by adding a coloring pigment or a decorative material to the surface layer molding material, the same design effect as when a paint is applied to the surface of an inorganic plate can be obtained, and a coating treatment is not required, and a further coating effect can be obtained. Improvements in production efficiency and cost reduction can be achieved.

Further, since the cylindrical rotator 25 for adsorbing and dewatering the cake layer 36 rotates integrally with the filter cloth 21, the friction of the filter cloth 21 can be reduced, and the durability of the filter cloth 21 can be improved. At the same time, the driving source of the driving roller 22 for driving the filter cloth 21 can also save power.

Furthermore, the cylindrical rotating body 25 is divided into four regions at 90 ° pitches. In the adsorption region, the degree of vacuum is increased to enhance the adsorption performance, and the thick cloth cake layer 36 is adsorbed on the filter cloth 21. In the dewatering region, the pressure can be reduced by a large suction air volume to improve the dewatering performance. Furthermore,
Since the area where the filter cloth 21 separates is a non-depressurized area, the filter cloth 21 does not need to be adsorbed to the cylindrical rotating body 25 in this area.
Can be drawn straight out smoothly, and unnecessary decompression can be avoided, and efficient decompression (adsorption and dehydration) can be performed.

In the above embodiment, the reduced pressure (vacuum degree) is the same for the suction area, but since the thickness of the cake layer 36 gradually increases from the suction area, the vacuum degree of the suction area is reduced. May be made higher than that of the suction region to enhance the suction performance of the suction region.

[0038]

As is apparent from the above description, according to the first aspect of the present invention, in the suction area of the cylindrical rotating body, the degree of vacuum is increased to enhance the suction performance, and the thick cloth cake layer is formed on the filter cloth. In the dewatering area, the pressure is reduced by a large suction air volume to increase the dewatering performance, and the surface layer molding material is sprayed on the surface of the cake layer adsorbed on the filter cloth from above this dewatering area. As compared with the papermaking method, it is possible to efficiently form a deep uneven pattern while improving the vertical tensile strength and the freeze-thaw performance.

According to a second aspect of the present invention, the cylindrical rotator may be
It is divided into four areas at a pitch and the area where the filter cloth separates is a non-depressurized area, so that the filter cloth can be pulled out straight straight from the upper end of the peripheral surface of the cylindrical rotating body and avoid unnecessary pressure reduction. In addition, efficient pressure reduction (adsorption / dehydration) can be performed.

According to the third aspect of the present invention, since a slurry to which a coloring pigment is added is used as the surface layer molding material, the same design effect as when a paint is applied to the surface of an inorganic plate can be obtained. No longer required, further improving production efficiency
Cost reduction can be achieved.

According to the fourth aspect of the present invention, a powder molding material or a material obtained by adding a resin emulsion to the powder molding material is used as the surface layer molding material. To improve the production efficiency, or increase the vertical tensile strength by spraying a resin emulsion.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an entire papermaking apparatus showing an embodiment of the present invention.

FIG. 2 is a sectional view of a main part.

FIG. 3 is a schematic configuration diagram of a dry spraying device.

FIG. 4 is a schematic configuration diagram of another dry spraying device.

FIG. 5 is a schematic configuration diagram of the entire conventional papermaking apparatus.

[Explanation of symbols]

21: filter cloth, 22: drive roller, 25: cylindrical rotating body,
26: cake-like material, 30: storage tank, 31: slurry, 3
3 stirrer, 35 rotary valve, 36 cake layer,
37: slurry (surface layer molding material), 38: wet pouring device, 40: suction box, 42: cutter, 44,
45 ... Dry spraying device.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B28B 1/52

Claims (4)

(57) [Claims] 1. A slurry prepared by mixing reinforcing fibers and a hydraulic substance with water is stored in a storage tank, and a cylindrical rotating body wrapped with an endless belt-shaped filter cloth is immersed in the slurry in the storage tank. Depressurizing the inside of the cylindrical rotating body while rotating it, thereby adsorbing a cake layer on the surface of the filter cloth in the slurry, dewatering and pressing the cake-like material to produce an inorganic plate for building. In the method, the upper surface of the filter cloth is stretched substantially horizontally, and the cake-like substance adsorbed on the filter cloth is transported in a substantially horizontal direction, and the cylindrical rotating body is adsorbed on the cake layer in the slurry. And a dewatering area for dewatering the cake layer that has escaped upward from the liquid surface of the slurry. Separate pressure reducing devices are connected to the respective areas via a rotary valve. High degree Enhanced adsorption performance Te,
In the dewatering region, the pressure can be reduced by a large suction air volume, and a surface layer molding material is sprayed onto the surface of the cake layer adsorbed on the filter cloth from above the dewatering region. Manufacturing method. 2. The method according to claim 1, wherein the cylindrical rotating body is divided into four regions at a pitch of 90 °, two lower regions being the adsorption regions, an upper region contacting the filter cloth being the dewatering region, The method for producing an inorganic plate according to claim 1, wherein the remaining one area from which the filter cloth is separated is a non-depressurized area. 3. A slurry to which a coloring pigment is added is used as a surface layer forming material sprayed on the surface of the cake layer from above the dewatering region.
3. The method for producing an inorganic plate according to item 1. 4. A powder molding material or a powder molding material obtained by dry-mixing a reinforcing fiber with a hydraulic powder as a main component as a surface layer molding material sprayed on the surface of the cake layer from above the dewatering region. The method for producing an inorganic plate according to claim 1, wherein a material obtained by adding a resin emulsion to the inorganic plate is used.