JPH10264123A - Manufacture of inorganic molded plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mold a thick three-tier structure inorganic molded plate. SOLUTION: A back face layer A is formed by spreading a raw material for molding which is dry or has a content of moisture of 60% or less over a molding conveyor 23. In addition, an inorganic sheet-like material is formed by making a sheet of slurry 18 prepared by mixing a main raw material with water using a sheet making device 10, and the inorganic sheet-like material is roughly crushed by a rotor 30 for rough crushing and spreading and at the same time, the rough crushings are spread and laminated uniformly on the supper surface of the back face layer A to form an intermediate layer B. Further, on the upper surface of the intermediate layer B, the raw material for molding which is dry and has a content of moisture of 60% or less is spread as is the case with the back face layer A, to form a front face layer C. Thus a three-tier structured laminated inorganic mat 38 is formed and then is molded by compression using a roll press 3. After that, the laminated inorganic mat 38 is press-molded using the template of a flat plate press to form an uneven pattern on the surface of the mat 38. Finally, the inorganic molded plate is manufactured by thermally curing the mat 38.

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 molded plate by press-molding a laminated inorganic mat having a three-layer structure.

[0002]

2. Description of the Related Art In recent years, inorganic molded plates have been frequently used as exterior materials and roof materials for houses. The method for producing the inorganic molded plate is such that an inorganic mat is molded by a wet method (papermaking method) or a dry method using a molding raw material in which cement and fibers are blended, and this is subjected to press molding to form an uneven pattern on the surface. A certain inorganic molded plate is formed. In order to press-mold a deeply carved pattern having high designability, it is necessary to increase the thickness of the inorganic mat, and from the viewpoint of improving durability, it is also desired to improve the strength of the inorganic molded plate.

Therefore, as disclosed in JP-A-4-364902, it has been proposed to press-mold a laminated inorganic mat having a three-layer structure to produce an inorganic molded plate. In the method for producing a laminated inorganic mat of this publication, a cement slurry containing reinforcing fibers is supplied in a layer form on a forming belt to form a back layer, and a dried cement compound is supplied in a layer form on the upper surface of the back layer. To form a three-layered laminated inorganic mat on the upper surface of the intermediate layer by supplying a cement slurry containing reinforcing fibers in the form of a layer on the upper surface of the intermediate layer, similarly to the back layer. I have to.

[0004]

In the above method for forming a laminated inorganic mat, since both the back surface layer and the surface layer are formed of cement slurry, it is necessary to dehydrate both the back surface layer and the surface layer. The cement slurry of the back layer can be dewatered through the forming belt, but the cement slurry of the surface layer is difficult to dewater through the forming belt, so the cement slurry of the surface layer contains moisture in the dry cement compound of the intermediate layer. Only a small amount can be supplied, and the thickness of the surface layer becomes extremely thin. In addition, when the amount of the dry cement composition in the intermediate layer is increased, the amount of water necessary for moistening the dried cement composition is also increased. However, when the cement slurry in the surface layer is increased in order to secure this moisture amount, the cement slurry is increased. Flows out from the middle layer. Therefore, the amount of the dry cement composition in the intermediate layer cannot be increased so much, and the intermediate layer also becomes thin. As a result, the thickness of the entire laminated inorganic mat is reduced, and
This leads to a reduction in the formability and strength of the uneven pattern.

The present invention has been made in view of such circumstances, and accordingly, an object of the present invention is to provide an inorganic molded plate capable of easily molding a thick laminated inorganic mat and improving both the moldability and strength of the concavo-convex pattern. It is to provide a manufacturing method.

[0006]

According to a first aspect of the present invention, there is provided a method of manufacturing an inorganic molded plate, wherein a main raw material is mixed in a dry state or a water content of 60% or less. A forming material is sprayed on a forming conveyor to form a back layer, and a slurry prepared by mixing the main material with water is formed by a paper forming apparatus to form an inorganic sheet, and the inorganic sheet is roughly crushed. While being coarsely pulverized by a dispersing means, the intermediate material is dispersed and laminated on the upper surface of the back layer to form an intermediate layer. Is formed by spraying the forming raw materials mixed in the step (a) to form a surface layer to form a laminated inorganic mat having a three-layer structure, press-molding the laminated inorganic mat, and curing and curing the mat.

According to this manufacturing method, both the back surface layer and the front surface layer are formed in a dry state or a forming raw material having a water content of 60% or less. Therefore, the back layer and the surface layer having the required thickness can be easily formed without causing the problem of dewatering the slurry and the problem of the slurry flowing out as in the related art. The intermediate layer is formed by dispersing and laminating the inorganic sheet-like material formed by sheet-forming the slurry with a paper-making apparatus on the upper surface of the back layer while coarsely pulverizing the inorganic sheet. The raw materials are sufficiently mixed to form a homogeneous intermediate layer with little variation in density, and the intermediate layer does not need to be dehydrated or wetted, so that an intermediate layer having a required thickness can be easily formed.

Further, the fibers to be mixed with the forming raw material for forming the back surface layer and the surface layer have a length of 5 m.
It is preferable to use a long fiber of m to 30 mm (a conventional general fiber length is 2.5 mm or less). Thus, by using long fibers, the reinforcing effect of the fibers can be enhanced.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. First, based on FIG.
0 will be described. The endless filtration belt 11 is formed of a band-shaped filter cloth or a water-permeable felt,
2. It is wound around a large-diameter cylindrical rotating body 14 via a plurality of tension rollers 13 and 22. Filtration belt 11
Travels in a substantially horizontal direction from the upper end of the peripheral surface of the cylindrical rotating body 14 toward the drive roller 12, and conveys the inorganic sheet material formed by the filtration belt 11 in the horizontal direction. A whipper roll 15 and a filtration belt cleaning device 16 are provided in the traveling path of the filtration belt 11 from the driving roller 12 to the cylindrical rotary member 14. The whipper roll 15 is constituted by a rotating body having a water spraying function, and scrapes the residue on the surface of the filter belt 11 while spraying water on the filter belt 11 to prevent the filter belt 11 from being clogged.

On the other hand, the cylindrical rotating body 14 is formed in a porous or mesh shape, and its lower half is immersed in a slurry 18 of a forming raw material stored in a storage tank 17. At the bottom of the storage tank 17, a plurality of agitators 19 are provided for agitating and uniformizing the slurry 18.

The inside of the cylindrical rotary member 14 is divided into four regions at 90 ° pitches, and the regions sink below the liquid surface of the slurry 18 to form adsorption regions. The filtration belt 11 stretched around the cylindrical rotary member 14 is tensioned by a tension roller 22 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. These four
The two areas are not rotated even when the cylindrical rotating body 14 rotates, and are fixed at a fixed position.

A plurality of suction pipes (not shown) for applying a suction force to the outer peripheral surface of the cylindrical rotary member 14 are radially provided on a rotary valve 20 provided at the center of the cylindrical rotary member 14. Have been. This cylindrical rotating body 14
Is connected to a vacuum pump (not shown) or the like via a rotary valve 20 so that a thick inorganic sheet material can be adsorbed to the filter belt 11 by the vacuum suction force. The dewatering region is connected to a suction port of a high-pressure blower (not shown) via a rotary valve 20, so that dehydration can be performed with a large suction air volume. On the other hand, the non-decompressed area is not decompressed, and therefore,
In the non-depressurized region, the filtration belt 11 does not need to be adsorbed to the cylindrical rotating body 14, and the filtering belt 11 can be smoothly drawn straight from the upper end of the peripheral surface of the cylindrical rotating body 14 in the transport direction. I have.

A dewatering box 21 is provided on the lower surface side of the filtration belt 11 which conveys the inorganic sheet material adsorbed and dewatered by the cylindrical rotary member 14. The dewatering box 21 is connected to a Nash pump (not shown). ), The inorganic sheet material on the filtration belt 11 is dehydrated under reduced pressure.

Using the space in front of the papermaking apparatus 10 configured as described above, the forming conveyor 23 is installed in an inclined manner so as to have an upward slope. This molding conveyor 23 is also the same as the filtration belt 11 of the papermaking apparatus 10,
It is composed of a band-shaped filter cloth or a water-permeable felt, and is stretched between a driving roller 24 and a driven roller 25.
On the lower side of the molding conveyor 23, a hopper 26 for storing a molding material for a back layer having a composition shown in Table 1 described later is installed. At an outlet of the hopper 26, a molding material for the back layer is formed. A forming material discharge roll 27 is provided on the base material 23 to be dispersed and supplied to form the back layer A. Into the hopper 26, a forming material for a back layer is sent from a forming material supply device 28 by a transport conveyor 29.

A watering nozzle 35 is provided below the papermaking apparatus 10, and the watering from the watering nozzle 35 wets the forming material of the back layer A on the forming conveyor 23. A pair of crushing / dispersing rotators 30 (crushing / dispersing means) is provided below the front end in the transport direction of the filtration belt 11 of the papermaking apparatus 10, and the inorganic sheet material formed on the filtration belt 11 is provided on both sides. In the process of falling onto the forming conveyor 23 through the crushing / dispersing rotator 30, the inorganic sheet-like material is coarsely crushed by both the crushing / dispersing rotators 30, and The intermediate layer B is formed by being dispersed and laminated on the upper surface.

In this case, in order to drop the inorganic sheet material from the front end of the filtration belt 11 in the conveyance direction, the drive roller 12 located inside the front end of the filtration belt 11 in the conveyance direction is made porous or mesh-like. The inorganic sheet material is forcibly dropped from the front end of the filtration belt 11 in the conveyance direction by air blow by blowing air from a blower (not shown) or the like into the inside.

On the other hand, on the upper side of the molding conveyor 23, a hopper 31 for containing a molding material for a surface layer having the composition shown in Table 1 described later is provided. A forming material discharge roll 32 for forming a surface layer C by dispersing and supplying the material to the upper surface of the intermediate layer B on the forming conveyor 23 is provided. Into the hopper 31, a forming material for a surface layer is sent from a forming material supply device 33 by a conveyor 34. A watering nozzle 36 is provided in front of the hopper 31 in the transport direction, and water is sprayed from the watering nozzle 36 so that the surface layer C on the forming conveyor 23 is formed.
Is moistened. Instead of the water spray nozzle 36, a slurry spraying device for spraying the slurry of the forming raw material may be installed.

A roll press 37 is provided in front of the watering nozzle 36 in the transport direction. This roll press 37
Is rotated at the same speed as the molding conveyor 23, and a three-layer laminate of molding materials is compression-molded by a roll press 37 to form a laminated inorganic mat 38 having a three-layer structure. A dewatering box 39 is provided below the roll press 37 with the forming conveyor 23 interposed therebetween, and the dewatering box 39 is evacuated by a Nash pump (not shown) or the like, so that the lamination compressed by the roll press 37 is formed. The inorganic mat 38 is dewatered under reduced pressure. Note that a flat plate press may be used instead of the roll press 37.

Using the molding apparatus constructed as described above, 3
A method of forming the laminated inorganic mat 38 having a layer structure will be described. The composition of the forming raw material for each layer is as shown in Table 1 below.

[0020]

[Table 1]

The long fibers to be mixed with the forming raw materials of the back layer A and the front layer C are synthetic fiber bundles having a length of 5 mm to 30 mm, such as vinylon fiber, polypropylene fiber, acrylic fiber, etc.
A chopped strand having a length of 10 mm to 25 mm of alkali-resistant glass fiber may be used. As the length of the long fibers increases, the reinforcing effect increases, but on the other hand, as the length increases, the long fibers are more likely to be entangled and difficult to uniformly disperse. Therefore, to achieve both the dispersibility and the reinforcing effect, 5 mm to 30 mm Is appropriate. These long fibers are not blended in the raw material for forming the intermediate layer B. This is because long fibers tend to be entangled and clump together in the slurry of the forming raw material, which causes a problem in dispersibility.

The forming materials for the back layer A and the surface layer C are mixed in a dry state or a state of a water content of 60% or less, and stored in forming material supply devices 28 and 33. Then, the forming raw materials in the forming raw material supply devices 28 and 33 are transferred to the conveyor 2.
The hoppers 9 and 34 are supplied into the hoppers 26 and 31. From the discharge port of the hopper 26 for the back layer, the forming material discharge roll 2
7, the forming raw material for the back layer is uniformly dispersed and supplied onto the forming conveyor 23, and the back layer A is formed. This back surface layer A is being conveyed by the molding conveyor 23,
It is moistened by the water spray from the water spray nozzle 35.

On the other hand, a forming material for forming the intermediate layer B is mixed with water to form a slurry 18, and this slurry 18 is stored in the storage tank 17 of the papermaking apparatus 10, and the endless filtration belt 1 is formed.
1 is immersed in the slurry 18 in the storage tank 17 and rotated while depressurizing the inside of the cylindrical rotator 14 so that the filtration belt 1
The molding material is conveyed while being continuously adsorbed on the surface of the first material.
As a result, the inorganic sheet-like material adsorbed on the filtration belt 11 is continuously conveyed to the front end of the filtration belt 11 in the conveyance direction.

The inorganic sheet-like material falls from the front end in the conveying direction of the filtration belt 11 by air blowing, and is coarsely pulverized by the crushing / dispersing rotating body 30 on the way, thereby forming the back layer A on the forming conveyor 23. The intermediate layer B having a uniform thickness is formed by being evenly dispersed and laminated on the upper surface.

The forming material for the surface layer is uniformly dispersed and supplied onto the upper surface of the intermediate layer B by the forming material discharge roll 32 from the discharge port of the hopper 31 for the surface layer, and the surface layer C is formed. The surface layer C is moistened by water spray from the water spray nozzle 36 while being transported by the molding conveyor 23.

The laminate of the molding raw materials thus laminated into three layers is compression-molded by a roll press 37 and
A laminated inorganic mat 38 having a layer structure is formed. The laminated inorganic mat 38 is conveyed to the next step of providing a concavo-convex pattern press, and the laminated inorganic mat 38 is press-molded with a template (not shown) of a flat plate press. As shown in FIG. An inorganic formed plate 38 'having a pattern is formed. Thereafter, the inorganic molded plate 38 ′ is conveyed to a heat-curing curing step, and is heated and cured in an atmosphere at a temperature of 80 ° C. and a humidity of 90 to 95% for 8 hours, after which moisture evaporates from the surface of the inorganic molded plate 38 ′. Wrapping to prevent
Cured for 15 hours in an atmosphere of Thereafter, the inorganic molded plate 38 'is commercialized through a decorative finishing process such as painting.

Incidentally, the curing method is not limited to the above method, and the curing may be performed by a usual autoclave.

The inventor measured the physical properties of the inorganic molded plate 38 'of the example manufactured as described above, and obtained the measurement results shown in Table 2 below.

[0029]

[Table 2]

In Table 2, in Comparative Example 1, an inorganic sheet was formed by forming a slurry having the composition shown in Table 3 below using a flow-on paper machine (paper machine that supplies slurry onto a filtration belt). Then, the inorganic sheet-like material is wound around a making roll by eight layers, and the resulting inorganic mat is cut and expanded, and the resulting inorganic mat is press-molded with a flat plate press template.
It is an inorganic molded plate produced by performing the same curing and curing as in the example.

[0031]

[Table 3]

In Comparative Example 2, the slurry having the composition shown in Table 3 was formed by a flow-on paper machine to form an inorganic sheet, and the inorganic sheet was added to a making roll.
After winding the layer, peeling and pulverizing it, dispersing and laminating it on a molding conveyor, compression-molding with a roll press, press-molding this inorganic mat with a template of a flat plate press, and then performing the same curing curing as in the example. This is an inorganic molded plate manufactured by the above method.

Comparing the physical properties of Comparative Examples 1 and 2 and the examples, as shown in Table 2 above, all of the physical properties of the examples are superior to those of the multilayer lamination method using the making roll of Comparative Example 1, and the inorganic materials It was found that a deep carved pattern could be formed on the surface of the molded plate. In addition, it was found that the bending strength of the example was significantly improved as compared with the comparative example 2.

In the above-described embodiment, the filtration type paper-making apparatus 10 is used, but instead, a flow-on paper machine or a Hacek-type paper machine may be used, or an inclined long net type paper machine. The inorganic sheet material may be formed using a papermaking machine.

Further, the composition of the forming raw material used in the method of forming the laminated inorganic mat 38 of the present invention is not limited to the above Table 1, and the forming method of the present invention is applied to the forming raw materials having various compositions in which cement and fibers are blended. Is applicable.

In the above embodiment, the filtration belt 11
In order to reliably remove the inorganic sheet from the front end in the conveying direction, an air blow method was adopted.
1. A scraping roll is installed near the front end in the conveyance direction,
The forming material may be scraped off from the front end in the conveying direction of the filtration belt 11 by the rotation of the scraping roll.

[0037]

As is apparent from the above description, according to the method for producing an inorganic molded plate of the present invention, the back layer and the surface layer are formed in a dry state or a molding raw material having a water content of 60% or less.
Since the intermediate layer is formed by crushing the inorganic sheet material formed by the papermaking apparatus, the back layer and the front surface of the required thickness can be formed without causing the problem of dehydration of the slurry and the problem of the slurry flowing out as in the related art. A layer can be easily formed, a uniform intermediate layer having a small variation in density can be formed thickly, a laminated inorganic mat having a thick three-layer structure can be easily formed, and both the moldability and strength of the concavo-convex pattern can be improved. .

Further, in the second aspect, the fibers to be mixed with the molding material for forming the back surface layer and the surface layer have a length of 5 m.
Since the long fibers having a length of m to 30 mm are used, the reinforcing effect of the long fibers can be enhanced while securing the dispersibility of the long fibers, and the strength can be further improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an apparatus for manufacturing an inorganic molded plate used in an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a part of an inorganic molded plate.

DESCRIPTION OF SYMBOLS 10 ... papermaking apparatus, 11 ... filtration belt, 12 ... drive roller, 14 ... cylindrical rotating body, 17 ... storage tank, 18 ... molding material slurry, 19 ... stirrer, 21 ... dehydration box, 2
3: molding conveyor, 26: hopper for back layer, 30: rotator for crushing / dispersing (crushing / dispersing means), 31: hopper for surface layer, 35, 36: watering nozzle, 37: roll press,
38: laminated inorganic mat, 38 ′: inorganic molded plate, 39
... dehydration box, A ... back layer, B ... intermediate layer, C ... surface layer.

Claims (2)

[Claims] 1. A method for producing an inorganic molded plate using cement and fibers as main raw materials, wherein a forming raw material obtained by mixing the main raw materials in a dry state or a water content of 60% or less is sprayed on a forming conveyor. Forming a back layer, forming a slurry by mixing the main raw material with water, forming an inorganic sheet-like material by a paper-making apparatus, and coarsely pulverizing the inorganic sheet-like material with a crushing and dispersing means. An intermediate layer is formed by dispersing and laminating on the upper surface of the back layer, and a forming material obtained by mixing the main raw material in a dry state or a water content of 60% or less is sprayed on the upper surface of the intermediate layer in the same manner as the back layer. Forming a three-layer laminated inorganic mat by press-molding the laminated inorganic mat, and curing and curing the laminated inorganic mat. 2. The method for producing an inorganic molded plate according to claim 1, wherein the fibers to be mixed with the molding material for forming the back layer and the surface layer are long fibers having a length of 5 mm to 30 mm. .