JP2003251618A - Inorganic plate and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inorganic plate for improving a productivity by improving a water-proofing performance of the inorganic plate product without applying an excess coating in the inorganic plate to be obtained by scattering a surface layer raw material on a surface of a base layer mat and forming by pressing, and to provide its manufacturing method. <P>SOLUTION: A base layer is formed by dehydrating after making a slurry having a cement and a reinforcing fiber material flow down in a form placed on a water-permeable sheet. A powder mixture having a cement and a reinforcing fiber material as principal components is laminated by scattering on an upper surface of the base layer, and hardened by curing after dehydration forming to provide the inorganic plate and its manufacturing method. A slurry containing a lightweight aggregate, an inorganic recycled plate raw material and a reinforcing fiber material is scattered on the base layer in the form, and the powder mixture having the cement and the reinforcing fiber material as main components is laminated by scattering on an upper surface of the slurry to provide the inorganic plate and its manufacturing method. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic plate used as a building material such as an outer wall material and a roof material, and a method for manufacturing the same.

[0002]

2. Description of the Related Art An inorganic plate of this type is prepared by dispersing a raw material mixture mainly composed of a hydraulic material such as cement and a reinforcing fiber substance such as pulp in water to form a slurry, and then mixing the raw material mixture on a water-permeable sheet. Is made to flow into a mat shape, dehydrated by a press machine, cured, and dried. These inorganic plates are manufactured by integrally molding a flat plate without a pattern and sometimes an uncured plate having a real part by dehydrating and molding an uncured mat with a press machine. In addition to this method, an embossed pattern is provided on the surface of the inorganic plate in order to give a three-dimensional change. In order to give this embossed pattern, when the mat is pressed and dehydrated, a press machine equipped with a template with a pattern formed on the surface is used. The conventional method is generally used, and various pattern patterns are applied to the inorganic plate.

Recently, in order to obtain a deep embossed pattern on the surface of an inorganic plate, a slurry in which a raw material mixture mainly composed of a hydraulic material such as cement and a reinforcing fiber material such as pulp is dispersed in water is permeable. There is provided a multi-layer type inorganic plate which is sprayed in layers on a sheet, and a raw material mixture having a different composition is sprayed on the upper surface thereof and then press-molded. As a method for obtaining such a deep embossed pattern, a powder material in which a surface layer material has a water content of 40% or less and a lightweight aggregate is blended in a specific range is spray-laminated and pressed to form a deep surface. Embossed patterns are used. (JP-A-61-149312) Further, in order to make the surface of the product smooth and dense, as a method of spraying the powder material on the surface raw material, powder cement having a small particle diameter is sprayed and then pressed. A method of making the surface layer portion dense by molding is adopted. (JP-A-6-19081
8)

[0004]

However, according to the above-mentioned conventional example, an embossed pattern having a certain depth can be applied to the surface of an uncured inorganic plate material by using a press, but the raw material used for the surface layer. Has a low water content and lacks in fluidity, so it corresponds to the part that constitutes the convex part of the inorganic plate when pressing, especially when molding with a press machine with a template with a pattern formed on the surface It is difficult for the raw material to move to the concave portions of the embossed pattern template, and porous portions are likely to be generated on the surface. As a result, pinholes, so-called bare holes are often generated on the surface of the porous portion, and the bare holes cause insufficient surface properties of the inorganic plate. If an inorganic plate is used as the outer wall material, water is likely to be absorbed from the holes due to rainfall and the like, which has a problem that the water permeation resistance of the Miki plate is adversely affected. These bare holes not only reduce the surface density and design, but also increase the amount of water permeation, which significantly deteriorates the durability of the product such as cracks due to expansion and contraction of water absorption and drying and deterioration of freeze-thaw performance.

Further, when the slurry is made to flow down into the mold placed on the water-permeable sheet to form the base layer, if the raw materials are not uniformly mixed, uneven spraying is likely to occur in the plate, which is more than usual. Since the thinly dispersed portion becomes porous, pinhole-shaped bare holes are likely to occur on the surface after press molding. Further, the base layer raw material which is a paste-like slurry is formed into a mat shape so that it can retain the shape by performing some dehydration before spraying the surface layer raw material, but when the dehydration of the base layer material is insufficient, Since the mat is in a soft state,
When the surface raw material is sprayed, the surface raw material gets into the base layer raw material, and the reverse phenomenon occurs in which the base layer raw material with a high water content is indexed to the surface layer surface. It is easy for holes to be generated.

In order to eliminate this phenomenon, a measure has been taken to improve the fluidity at the time of press molding by containing a large amount of water in the powder raw material of the surface layer. When mixed, there is a problem that the reinforcing fiber substance easily aggregates in a ball shape, and dehydration takes a long time during molding to deteriorate productivity, and if dehydration is insufficient, the surface property of the portion is deteriorated. It was Furthermore, a means to improve the water permeation resistance by applying a coating to the surface of the inorganic plate is taken, but a certain amount of coating is required to completely hide the bare holes, and to improve the water permeation resistance of the original plate. Had a problem that the coating cost would increase. Further, in order to make the product surface denser, a means of further dispersing the powder material on the surface layer raw material is taken, but since the raw material having a small particle size is dispersed on the surface layer, it is possible to make fine particles on the surface of the template after molding. The powder material is likely to adhere to the surface of the molded product, which worsens the quality of the product.Because new equipment is required to disperse raw materials with small particle size, the manufacturing equipment becomes large and the manufacturing cost is high. There was a problem that it would raise. That is, until now there is no need for excessive coating, and the surface of the inorganic plate is made smooth and dense without any holes without increasing the manufacturing cost.
In particular, improving the water permeation resistance of an inorganic plate has been an important issue in terms of its performance. The present invention has been made to solve the above problems, in the inorganic plate obtained by spraying the surface layer raw material on the surface of the base layer mat and press dehydration molding and its manufacturing method, without applying excessive coating It is an object of the present invention to provide an inorganic plate that improves the surface property of a plate product and improves productivity, and a method for manufacturing the same.

[0007]

In order to achieve the above object, the present invention relates to a first aspect of the present invention, wherein a slurry containing cement and a reinforcing fiber material as main components is placed in a formwork placed on a water permeable sheet. An inorganic plate obtained by dehydration and then dehydration to form a base layer, and by spraying and laminating a powder mixture containing cement and a fiber reinforcing substance as a main component on the upper surface of the base layer, followed by dehydration molding and curing. The base layer is a slurry containing a lightweight aggregate, a recycled raw material for an inorganic plate, and a reinforcing fiber substance, and is obtained by spraying and laminating a powder mixture containing cement and a fiber reinforcing substance as main components on the upper surface of the base layer. It is intended to provide an inorganic plate. According to the above configuration, since the slurry containing the lightweight aggregate, the recycled inorganic plate material, and the reinforcing fiber substance becomes bulky, the pressure at the time of pressing becomes high, and at the same time, the high pressing pressure uniformly reaches the surface layer. In addition, when the embossed pattern is press-molded, the raw material easily moves to the concave portion of the template having the embossed pattern formed on the surface, so that the surface layer material becomes dense and becomes an inorganic plate having no holes. Further, since the base layer raw material is bulky, it is easily dispersed at the time of mixing to form a uniform slurry, so that the slurry that has flowed into the mold has no uneven thickness. In addition, since the base layer becomes bulky and becomes a porous slurry with increased dehydration holes, productivity is improved, and since the base layer surely becomes a mat having shape retention property, it is spread on the base layer mat. The surface layer raw material does not sink into the base layer, and the surface of the inorganic plate after press dehydration molding has no pinhole-shaped holes.

According to the second aspect of the present invention, a slurry containing cement and a reinforcing fiber substance as main components is made to flow down into a mold placed on a water-permeable sheet and then dehydrated to form a base layer. A method for producing an inorganic plate, in which a powder mixture containing cement and a fiber reinforcing substance as a main component is sprayed and laminated on the upper surface and cured by curing after dehydration molding, wherein the base layer is a lightweight aggregate, a recycled material for the inorganic plate, and a reinforcing material. Provided is a method for producing an inorganic plate, which comprises flowing down a slurry containing a fibrous substance into a mold, and spraying and laminating a powder mixture containing cement and a fiber-reinforcing substance as main components on the upper surface of the slurry. To do. According to the above configuration, since the raw material forming the base layer is bulky, the pressure at the time of pressing is high, and since a high pressing pressure is evenly applied to the surface layer, the embossed pattern is pressed. Since the raw material easily moves to the concave portion of the template having the embossed pattern, the surface layer material becomes dense and it becomes possible to easily manufacture the inorganic plate without the hole. Further, since the base layer raw material is bulky, it is easily dispersed during mixing to form a uniform slurry, so that the slurry that has flowed into the mold can flow to a uniform thickness. Also, since the base layer becomes bulky, the dehydration holes increase,
It is possible to improve the drainage and to produce an inorganic plate with good productivity, and also the base layer mat has a certain degree of shape retention, and the surface layer raw material sprinkled on the base layer mat does not go into the base layer, Since the surface layer can be surely spread and laminated with a uniform thickness, an inorganic plate having a good surface property can be manufactured.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. The inorganic plate according to the present invention is composed of a base layer and a surface layer, and a slurry in which a raw material mixture mainly composed of a hydraulic material such as cement and a reinforcing fiber substance such as pulp is dispersed in water is layered on a water-permeable sheet. The base material is a mat that flows down and is dehydrated to form a base layer, and on top of that, a raw material is prepared by layering a powder raw material mixture of a different composition mainly composed of a hydraulic material such as cement and a reinforcing fiber substance such as pulp in a surface layer. And an inorganic plate obtained by press dehydration molding. Here, examples of the hydraulic material include Portland cement, blast furnace slag cement, silica cement, fly ash cement, and alumina cement. As the reinforcing fiber substance, for example, wood chips, wood pulp, wood fiber bundles, wood wool, wood powder, synthetic fibers, etc. are used, but polyester fibers, polyamide fibers, acrylic fibers, polyvinylidene chloride fibers, acetate fibers, etc. Other organic fibers or inorganic fibers such as sepiolite, wollastonite, and glass fibers may be used.

Further, in the present invention, in addition to the above components, for example, silica gel, silica stone powder, silica fume, blast furnace slag, fly ash, silas balloon, perlite, bentonite, inorganic filler such as silicic acid-containing substance such as diatomaceous earth, Anhydrous or crystallized chloride such as calcium chloride, magnesium chloride, iron chloride, aluminum chloride, sodium chloride, potassium chloride, lithium chloride, aluminum sulfate, alum, iron sulfate, lithium sulfate, sodium sulfate, potassium sulfate, magnesium sulfate Anhydrate or crystallized product of sulfate, etc., nitrate such as calcium nitrate, calcium nitrite, inorganic product or crystallized product of nitrite, formate such as calcium formate, calcium acetate, anhydride or crystallized product of acetate, aluminate Cement hardening accelerator for soda, water glass, etc. Waxes, paraffins, water repellent agents such as silicon, expandable thermoplastic plastic beads such as foamed polystyrene beads may be added.

In order to produce the inorganic plate of the present invention, the mixture of the above raw materials is dispersed in water to form a slurry, and the slurry is supplied onto a water-permeable sheet and suction-dehydrated from the back surface of the sheet to form a mat. A method is adopted in which the powder raw material is sprinkled in layers on the upper surface, press-dehydrated and then cured and cured. Cements and silicic acid-containing substances are preferably used as raw materials used for the base layer of the inorganic hardened layer, and the total amount of the cements and the silicic acid-containing substance is 60 to 95 wt% in the base layer raw material. And the ratio of the cements to the silicic acid-containing substance is usually 70:30 to 30:70 by weight. The reinforcing fiber substance dispersed in the base layer raw material is usually 5% in the raw material.
It is added in an amount of ˜15% by weight, and when synthetic fibers are added, it is usually added in an amount of 5% by weight or less in the raw material. The silicic acid-containing substance allows the inorganic plate to be smoothly and completely cured by the reaction between cement and calcium silicate, and the dimensional stability of the obtained product is improved.

Further, in the present invention, a lightweight aggregate, a recycled raw material for an inorganic plate, and a raw material having a low bulk specific gravity of the reinforcing fiber material are contained to produce a bulky slurry. When the lightweight aggregate is added, the lightweight aggregate is usually contained in the raw material in an amount of 1 to 15% by weight,
In addition, when adding the inorganic plate recycling raw material, it is preferable to use the raw material which is usually 1 to 20% by weight in the raw material. These raw materials reduce the weight of the inorganic plate to be produced and make the slurry bulky, so they are essential components for the present invention, but when the content becomes more than the necessary amount in the mixture, the specific gravity decreases and the reinforcing fiber substance aggregates. The strength of the resulting inorganic plate tends to decrease.

On the other hand, the surface layer of the inorganic hardened layer is a semi-dry powder raw material mixture to which a small amount of water is added, and is formed on the upper surface of the base layer. Similar to the base layer, the surface layer is mainly composed of cements and reinforcing fiber substances, desirably the cements and the silicic acid-containing substance are used, and the total amount of the cements and silicic acid-containing substance is 60 to 95% by weight. %
And the ratio of the cements to the silicic acid-containing substance is usually 70:30 to 30: 7 by weight.
It is set to 0. Further, it is desirable to use 0 to 10% by weight of the reinforcing fiber substance and 0 to 7% by weight of the lightweight aggregate to be dispersed in the surface layer raw material. Further, it is desirable that the base layer slurry is 70 to 95% and the surface layer powder raw material is 5 to 30% with respect to the total solid content with respect to each amount of the base layer and the surface layer.

As shown in FIG. 2, the facility for producing an inorganic plate according to the present invention comprises a base layer slurry pouring device 2, a surface layer powder spraying device 3, a press dehydration molding device 4, a movable water permeable sheet 5,
The suction / dehydration device 8 and the conveyor belt 9 are included. That is, the base layer slurry pouring device 2 is provided with a slurry storage tank 21, the surface layer powder spraying device 3 is provided with a powder mixture storage tank 22, and the suction dewatering device 8 is provided with a suction machine. There is. On the other hand, the press dehydrator 4 is a press 5
The press 51 includes an upper plate 52 and a lower plate 54. Here, the lower plate 54 is provided with a suction dehydrator and is fixed to the main body of the press 51, while the upper plate 5 is
An embossed mold plate 53 having a pattern formed on its surface is fixed to the surface 2, and they are supported so as to be vertically movable. A water-permeable sheet 5 is rotatably stretched around the slurry pouring device 2, the surface-layer powder-dispersing device 3, the pressing dehydration molding device 4, and the suction dehydration device 8 in order. A conveyor belt 9 is stretched in the vicinity of to be rotatably driven.

The base layer raw material is usually mixed with water so as to have a water content of 300 to 400% to form a slurry. The kneaded slurry is poured into a mold 10 placed on a mesh-shaped water permeable sheet 5 in a predetermined amount and supplied, and after the slurry is leveled, a suction dehydrator 8 is applied from the back surface of the water permeable sheet.
The suction device is driven to suck and dehydrate from the lower surface of the slurry. After dehydration, the water content of the slurry has been reduced to such a degree that the shape is maintained, and the water content is usually 150 to 200%.
The flat-plate mat 11 is formed in the mold. afterwards,
The water permeable sheet 5 is rotated and transferred to the vicinity of the surface layer raw material spraying device 3, and the powder raw material 12 is uniformly sprayed on the base layer mat. Here, it is desirable that the application rate of the powder raw material is 5 to 30% by weight based on the solid content of the base material. After spraying the surface layer, the mold 10 is removed and only the mat is left on the water permeable sheet, and the water permeable sheet 5 is rotatively moved to transfer the mat to the vicinity of the press dehydration molding device 4, and then on the press dehydration molding device. The upper plate is lowered by a predetermined stroke while being positioned between the plate 52 and the lower plate 54. By pressing with such a press dehydration molding apparatus, it is dehydrated and molded into a plate shape, and if desired, a pattern is attached to the mat surface by the template 53 fixed to the upper plate. The inorganic plate manufactured in this way is transferred to a curing step and hardened, but is cut into a predetermined size before or after the curing. For curing, the mat is usually left unheated or left under heating and atmospheric pressure for 6 to 30 hours in a closed chamber for primary curing, and then usually 160 to 180.
A two-stage curing method is used in which autoclave curing is performed at 6 ° C. for 6 to 15 hours to completely cure. After curing and curing, the cured mat is subjected to trimming, painting, etc., if desired, to give an inorganic plate product.

[0016]

EXAMPLES Examples of the present invention will be described below. Example 1 A raw material mixture having the following composition is prepared as a raw material for a base layer. 40% by weight of Portland cement, 39% by weight of silica stone powder,
Perlite 6.7% by weight, inorganic plate recycled raw material 6.
7% by weight, 6.7% by weight of pulp, and 1% by weight of synthetic fiber. The above raw material mixture is mixed with water and uniformly stirred to adjust the slurry to have a water content of 300%. The raw material slurry is poured into a mold placed on a water permeable sheet, leveled, and dehydrated for a certain period of time by a suction dehydrator installed on the lower surface of the water permeable sheet so that the water content of the slurry is 150%.

On the other hand, a raw material mixture having the following composition is prepared as a surface layer raw material. 42% by weight of Portland cement, 42% by weight of silica stone powder, 7% by weight of pearlite, 5% by weight of recycled inorganic plate, 3% by weight of pulp, 1% by weight of synthetic fiber, and water was added so that the water content becomes 20%. To obtain powder raw material. Then, 25% of this powder raw material is dispersed on the base layer with respect to the total solid content, and this is subjected to pressure dehydration molding with a pressing device equipped with a template having a pattern pattern on the surface so as to have a set thickness . The mat formed in this way is
A predetermined inorganic plate is obtained by performing primary curing at 60 to 80 ° C. for 6 to 30 hours and secondary curing at 160 to 180 ° C. for 6 to 15 hours in an autoclave.

Example 2 The composition of the raw material for the base layer is adjusted as follows. Portland cement 35% by weight, silica powder 34% by weight, perlite 10
% By weight, 10% by weight of recycled inorganic plates, 1 pulp
The slurry is adjusted to 0% by weight and 1% by weight of synthetic fiber.
Others are the same as the conditions used in Example 1, and an inorganic board is manufactured. Example 3 The composition of the raw material for the base layer is adjusted as follows. 35% by weight of Portland cement, 34% by weight of silica stone, 5% by weight of pearlite, 15% by weight of recycled inorganic board, 10% of pulp
A slurry is prepared by adjusting the weight to 1% by weight and the synthetic fiber to 1% by weight. Others are the same as that used in Example 1, and an inorganic board is manufactured. Example 4 The composition of the raw material for the base layer is adjusted as follows. Portland cement 35% by weight, silica powder 34% by weight, perlite 10
% By weight, 5% by weight of recycled inorganic board, pulp 15
A slurry is prepared by adjusting the weight to 1% by weight and the synthetic fiber to 1% by weight. Others are the same as that used in Example 1, and an inorganic board is manufactured. Comparative Example 1 A raw material mixture having the following composition is prepared as a raw material for a base layer. 40% by weight of Portland cement, 39% by weight of silica stone powder,
A slurry is prepared with 10% by weight of recycled inorganic plate, 10% by weight of pulp and 1% by weight of synthetic fiber. Others are the same as that used in Example 1, and an inorganic board is manufactured. Comparative Example 2 A raw material mixture having the following composition is prepared as a raw material for the base layer. 40% by weight of Portland cement, 39% by weight of silica stone powder,
Perlite 10% by weight, pulp 10% by weight, synthetic fiber 1
Adjust the slurry to make the weight percent. Others are the same as that used in Example 1, and an inorganic board is manufactured. Comparative Example 3 A raw material mixture having the following composition is prepared as a raw material for the base layer. 40% by weight of Portland cement, 39% by weight of silica stone powder,
Perlite 5.5% by weight, inorganic plate recycled raw material 5.
The slurry is adjusted to 5% by weight and 10% by weight of pulp.
Others are the same as that used in Example 1, and an inorganic board is manufactured.

The surface properties, productivity, and freeze-thaw resistance of various inorganic plates (Examples 1 to 4 and Comparative Examples 1 to 3) thus obtained were confirmed. The results are shown in Table 1. The surface quality is the appearance evaluation and the number of pinholes per square meter, the productivity is the production tact (sec) when manufacturing one sheet,
Freeze-thaw resistance was measured according to JIS A 1435 by observing the appearance of the surface after 200 cycles.

[Table 1]

As is clear from Table 1, the inorganic plate obtained as in Example 1 has an embossed pattern having a dense surface and no bare holes. In addition, since the dehydration pores increase due to the bulkiness of the base layer, drainage can be improved and an inorganic plate can be produced with good productivity. Also, since the base layer does not cause poor dehydration, the base layer mat has a certain degree of shape retention, and the surface layer raw material sprinkled on the base layer mat does not go into the base layer, and the surface layer should be spread and laminated to a uniform thickness. Therefore, it is possible to manufacture an inorganic plate having a good surface property. Moreover, Examples 2 to 4
Then, by making the base layer more bulky, it is possible to obtain an inorganic plate having further improved surface properties and productivity.

[0021]

Therefore, according to the present invention, since the raw material constituting the base layer becomes bulky, the pressure at the time of pressing becomes high, and at the same time, the high pressing pressure is uniformly applied to the surface layer,
Further, when the embossed pattern is press-molded, the raw material easily moves to the concave portion of the template having the embossed pattern, so that the surface layer material becomes dense and becomes an inorganic plate having no bare holes. Further, since the base layer raw material becomes bulky, it is easily dispersed during mixing to form a uniform slurry, so that the slurry that has flowed into the mold has a uniform thickness, and an inorganic plate having good surface properties can be manufactured. Further, since the base layer becomes bulky and becomes a porous material with increased dehydration pores, drainage is improved and productivity can be improved. In addition, since the base layer does not cause poor dehydration, a mat having a shape-retaining property is surely formed before the surface layer is sprayed.Therefore, the surface layer raw material sprayed on the base layer mat does not get caught in the base layer and has a pinhole shape. It is possible to manufacture an inorganic plate having a good surface property and having no bare holes.

[Brief description of drawings]

FIG. 1A is a mat cross-sectional view of a conventional inorganic plate before pressure dehydration molding. (B) A cross-sectional view of the mat of the present invention before pressure dehydration molding.

FIG. 2 is a side view showing a facility for manufacturing an inorganic plate according to the present invention.

FIG. 3 is a perspective view of a conventional product.

[Explanation of symbols]

2 Underlayer slurry pouring device 3 Surface powder disperser 4 Press dehydration molding device 5 Water-permeable sheet 6 cleaning equipment 7 Wastewater storage receiver 8 Suction dehydrator 9 Conveyor belt 10 Formwork 11 Base layer mat 12 Surface powder raw material 21 Base layer slurry storage tank 22 Surface powder mixture storage tank 51 Press 52 Upper board 53 template 54 Lower plate

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[Procedure amendment]

[Submission date] March 7, 2002 (2002.3.7)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

In order to achieve the above object, the present invention relates to a first aspect of the present invention, wherein a slurry containing cement and a reinforcing fiber material as main components is placed in a formwork placed on a water permeable sheet. An inorganic plate obtained by performing dehydration and then curing to form a base layer, spraying and laminating a powder mixture containing cement and a reinforcing fiber substance as a main component on the upper surface of the base layer, and dehydrating and curing. The base layer is a slurry containing a lightweight aggregate, a recycled raw material for an inorganic plate, and a reinforcing fiber substance, and is obtained by spraying and laminating a powder mixture containing cement and a reinforcing fiber substance as main components on the upper surface of the base layer. It is intended to provide an inorganic plate. According to the above configuration, since the slurry containing the lightweight aggregate, the recycled inorganic plate material, and the reinforcing fiber substance becomes bulky, the pressure at the time of pressing becomes high, and at the same time, the high pressing pressure uniformly reaches the surface layer. In addition, when the embossed pattern is press-molded, the raw material easily moves to the concave portion of the template having the embossed pattern formed on the surface, so that the surface layer material becomes dense and becomes an inorganic plate having no holes. Further, since the base layer raw material is bulky, it is easily dispersed at the time of mixing to form a uniform slurry, so that the slurry that has flowed into the mold has no uneven thickness. In addition, since the base layer becomes bulky and becomes a porous slurry with increased dehydration holes, productivity is improved, and since the base layer surely becomes a mat having shape retention property, it is spread on the base layer mat. The surface layer raw material does not sink into the base layer, and the surface of the inorganic plate after press dehydration molding has no pinhole-shaped holes.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

According to the second aspect of the present invention, a slurry containing cement and a reinforcing fiber substance as main components is made to flow down into a mold placed on a water-permeable sheet and then dehydrated to form a base layer. A method for producing an inorganic plate in which a powder mixture containing cement and a reinforcing fiber substance as main components is sprayed and laminated on the upper surface and cured by curing after dehydration molding, wherein the base layer is a lightweight aggregate, a recycled material for the inorganic plate, and a reinforcing material. Provided is a method for producing an inorganic plate, characterized in that a slurry containing a fibrous substance is flown down into a mold and a powder mixture containing cement and a reinforcing fibrous substance as a main component is sprinkled and laminated on an upper surface of the slurry. To do. According to the above configuration, since the raw material forming the base layer is bulky, the pressure at the time of pressing is high, and since a high pressing pressure is evenly applied to the surface layer, the embossed pattern is pressed. Since the raw material easily moves to the concave portion of the template having the embossed pattern, the surface layer material becomes dense and it becomes possible to easily manufacture the inorganic plate without the hole. Further, since the base layer raw material is bulky, it is easily dispersed during mixing to form a uniform slurry, so that the slurry that has flowed into the mold can flow to a uniform thickness. Also, since the base layer becomes bulky, the dehydration holes increase,
It is possible to improve the drainage and to produce an inorganic plate with good productivity, and also the base layer mat has a certain degree of shape retention, and the surface layer raw material sprinkled on the base layer mat does not go into the base layer, Since the surface layer can be surely spread and laminated with a uniform thickness, an inorganic plate having a good surface property can be manufactured.

Claims (2)

[Claims] 1. A slurry containing cement and a reinforcing fiber material as main components is made to flow down into a mold placed on a water-permeable sheet and then dehydrated to form a base layer, and the cement and the fiber are formed on the upper surface of the base layer. An inorganic plate obtained by spray-laminating a powder mixture containing a reinforcing substance as a main component, curing by dehydration molding, and curing, wherein the base layer contains a lightweight aggregate, a raw material for recycling an inorganic plate, and a fiber reinforcing substance. An inorganic plate obtained by forming a slurry, and spraying and laminating a powder mixture containing cement and a fiber reinforcing substance as main components on the upper surface of the base layer. 2. A slurry containing cement and a reinforcing fiber substance as main components is made to flow down into a mold placed on a water-permeable sheet and then dehydrated to form a base layer, and the cement and the fiber are provided on the upper surface of the base layer. A method for producing an inorganic plate in which a powder mixture containing a reinforcing substance as a main component is sprayed and laminated, and dehydration-molding is followed by curing and curing, wherein the base layer is a lightweight aggregate, an inorganic plate recycled material,
The slurry containing the reinforcing fiber substance is flowed down into the mold,
A method for producing an inorganic plate, characterized in that a powder mixture containing cement and a fiber-reinforcing substance as main components is sprinkled and laminated on the upper surface of the slurry.