JPH05221746A - Inorganic lightweight decorative laminated sheet and its production - Google Patents

Abstract

PURPOSE:To easily produce an inorganic lightweight decorative laminated sheet which is excellent in workability and has a large dimension by constituting the surface of a plurality of pieces of natural slates or sheets like a natural stone. CONSTITUTION:An inorganic lightweight sheet 22 whose thickness is 7-90mm per one piece is formed of the mixture of inorganic aggregate consisting of SHIRASU (pumiceous sand) baloon as a main component, water glass and a hardening agent thereof. An inorganic lightweight decorative lamianted sheet 20 is constituted of the inorganic lightweight sheet 22 and a plurality of pieces of natural slates or plates 4 like a natural stone having 3-20mm thickness which are laminated and bonded thereon. Void parts 21 satisfying the following formulas (1) and (2) are interposed between the adjacent natural slates or the plates 4 like the natural stone. 0<t/T<=0.8 (1). 1.5<=T/w<=10 (2) (however T shows thickness of natural slate or plate like natural stone and t shows depth of void part and w shows width of void part).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic lightweight decorative board having a plurality of natural stone boards or natural stone-like boards and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, natural stones have come to be favored in wall materials and floor materials of buildings in order to obtain a high-class feeling and a natural feeling. However, such a natural stone has a drawback that its cost is high, and since it has a large specific gravity, its weight is 1 m when its thickness is 20 to 30 mm.
^{It is} more than 60 kg per ² including the problem of poor workability. In addition, although specialized technology is required for stone construction,
The shortage of masons, which can be said to be chronic, delays the construction period, and even small-scale buildings, shops, and houses are inaccessible. Against the background of such a shortage of craftsmen, recently, a thin natural stone composite panel having good workability has been developed by slicing natural stone into a thickness of 5 to 10 mm and attaching a backing material of light weight to the back surface. This natural stone composite panel is a FRP sheet as a backup material,
Although it includes aluminum honeycomb core, ceramic material, plywood, etc., all of them are of a type to be manually attached, and there is a problem that they are expensive to manufacture and expensive, and warpage occurs due to difference in linear expansion coefficient due to heat. Had problems such as. Then, the present inventors previously proposed a decorative plate using a water glass cured product containing shirasu balloon as a main component as a backup material in order to solve the problems of working cost and warpage (Japanese Patent Application No. 2- 275792). However, in the case of this veneer, although problems such as the work cost in manufacturing the veneer could be solved, the work at the time of applying the veneer still requires skilled technology, and in order to solve the problem of construction The situation is that only a limited small size has been put to practical use.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, has excellent workability in that the surface is made of a plurality of natural stone plates or natural stone-like plates, and an inorganic material of large size can be easily obtained. It is an object of the present invention to provide a lightweight decorative board and a manufacturing method thereof.

[0004]

The present inventors have completed the present invention as a result of intensive studies to solve the above problems. That is, according to the present invention, one inorganic lightweight plate having a thickness of 7 to 90 mm formed from a mixture of an inorganic aggregate containing shirasu balloon as a main component, water glass, and a water glass curing agent, and laminating and adhering thereon. Multiple thicknesses 3-20
mm natural stone board or natural stone-like board, and an inorganic light-weight decorative board characterized in that a space satisfying the following formulas (1) and (2) is interposed between the adjacent natural stone boards or natural stone-like boards. Will be provided. O <t / T ≦ 0.8 (1) 1.5 ≦ T / w ≦ 10 (2) (where T is the thickness of the natural stone plate or the natural stone-like plate, t
Indicates the depth of the void, and w indicates the width of the void) Further, according to the present invention, the inside is divided into a plurality of partitions by the partition member that satisfies the following formulas (1) and (2). Inside each of the sections of the mold, a flat natural stone plate or natural stone-like plate corresponding to the flat shape of the section is applied with an adhesive on its upper surface and placed, and cured on the adhesive-coated surface. Inorganic lightweight makeup characterized by laminating a layer of inorganic aggregate mainly composed of shirasu balloon surface-coated with water glass containing a curing agent, pressurizing at room temperature or under heating, and reacting the curing agent with water glass A method of making a plate is provided. O <t '/ T≤0.8 (1) 1.5≤T / w'≤10 (2) (where T represents the thickness of natural stone or natural stone-like plate,
(t 'indicates the height of the partition member, and w'indicates the width of the partition member)

Natural stone plate or natural stone-like plate used in the present invention
Examples of natural stones such as marble and granite, as well as artificial marble and artificial ivory, which are made of acrylic resin, are used as (hereinafter, simply referred to as surface plates).

The inorganic aggregate used as the inorganic lightweight board material in the present invention contains shirasu balloon as a main component and, if necessary, pearlite, leucite, and other lightweight aggregates. The content rate of Shirasu balloon in the inorganic aggregate is
It is 50% by weight or more, preferably 80 to 100% by weight. As the shirasu balloon, commercially available products can be used as they are, but in the present invention, it is preferable to use a mixture of fine particles and coarse particles. A particularly preferred silas balloon used in the present invention has a content of a component having a particle size of 63 μm or less (hereinafter referred to as A component) in the range of 15 to 55% by weight, and a component having a particle size of 177 to 420 μm in the range (hereinafter referred to as B component). 25-65% by weight and particles 63 μm
Over 177 μm and component content over 420 μm 6
Component less than 00 μm (hereinafter, both are collectively referred to as C component)
It has a particle size distribution with a content of 0 to 40% by weight. A component is less than 15% by weight, B component is less than 65%
When the weight percentage is exceeded, the lightweight plate obtained has large shrinkage deformation, and the surface becomes prominently uneven. Further, the lightweight plate obtained when the amount of A component exceeds 55% by weight and the amount of B component is less than 25% by weight tends to warp as the shrinkage deformation increases, and in some cases (when B component approaches 0). A crack has occurred. Further, when the C component exceeds 40% by weight, the lightweight plate obtained has large shrinkage deformation.

The water glass used in the present invention means an aqueous solution of an alkali metal silicate such as sodium silicate, potassium silicate or lithium silicate, and for example JIS 1
No. standard product, JIS No. 2 standard product, JIS No. 3 standard product, etc. are commercially available. As the water glass curing agent, conventionally known ones, for example, inorganic acids such as phosphoric acid and boric acid and salts thereof, silicofluorides such as sodium silicofluoride, metals such as zinc oxide and magnesium oxide, calcium carbonate and calcium sulfate. Examples thereof include oxides, metal salts and acetic acid esters.

The molding material for producing the inorganic lightweight board in the present invention comprises a mixture of water glass, a curing agent and Shirasu balloon. The amount of water glass used is 30 to 150 parts by weight, preferably 40 to 1 in terms of solid content (alkali metal silicate) based on 100 parts by weight of Shirasu balloon.
30 parts by weight. If the proportion of water glass used is less than the above lower limit, the effect as a bonding material will be poor, and the resulting lightweight plate will have a markedly reduced strength, making it impractical. On the other hand, when the upper limit is exceeded, the proportion of unreacted water glass increases, and thus the resulting lightweight plate does not shrink,
It will be cracked. The curing agent for water glass is 10 to 40 parts by weight with respect to 100 parts by weight of Shirasu balloon,
It is preferably 15 to 30 parts by weight. If the amount of the curing agent used is less than the above lower limit value, the proportion of unreacted water glass increases, so that the resulting lightweight plate is accompanied by shrinkage and has cracks. On the other hand, when it exceeds the upper limit, the curing agent, the reaction rate of carbon dioxide gas and moisture in the air is significantly increased, so-called white flower phenomenon is observed,
White powder is spotted on the surface of the obtained lightweight plate or the surface plate laminated on the surface of the lightweight plate, so that the commercial value is significantly reduced.

In the present invention, in order to enhance the mechanical strength of the inorganic lightweight plate, a polymeric binder may be used in combination with the molding material. A water-soluble polymer or polymer latex can be used as the polymer binder. Examples of the water-soluble polymer include water-soluble urea / formamide resin and guanamine resin, as well as polyvinyl alcohol and polyvinylpyrrolidone. As the polymer latex, styrene / budadiene type latex, acrylic type latex, vinylidene chloride type latex, vinyl chloride type latex, vinyl acetate type latex and the like are used. The polymer binder is used in an amount of 0.5 parts by weight or more, preferably 1 to 10 parts by weight in terms of solid content, based on 100 parts by weight of Shirasu balloon. When the proportion of the polymer binder used is large, the nonflammability of the lightweight plate is impaired. Therefore, from the viewpoint of obtaining a nonflammable lightweight plate, the proportion of the polymer binder used is preferably 5 parts by weight or less.

The molding material used in the present invention may further contain a reinforcing fiber in order to prevent the occurrence of cracks in the inorganic lightweight plate and to enhance the mechanical strength.
Examples of the reinforcing fiber include vinylon fiber, acrylic fiber, aramid fiber, polyester fiber, polyamide fiber, cellulose fiber, cotton, carbon fiber and other synthetic fibers and natural fibers, as well as metal fiber, alumina fiber, glass fiber, gypsum whiskers and the like. Various metals and inorganic fibers are used. The thickness of the fiber is 1 to 100 μm, preferably 3 to 60 μm.
m, and the fiber length is 1 mm or more, preferably 3 to
It is 20 mm. The proportion of the reinforcing fiber used is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the Shirasu balloon.

Further, the above-mentioned molding material may be used in combination with unexpanded shirasu powder or an inorganic powder such as mica or kaolin in order to increase its viscosity and prevent shrinkage during molding and curing. .. The average particle size of such inorganic powder is 70
It is not more than μm, preferably 0.1 to 30 μm. Also,
The use ratio of such inorganic powder is as follows.
It is 30 parts by weight or less, preferably 20 parts by weight or less, relative to 0 parts by weight. Further, by adding about 3 to 20 parts by weight of ultrafine particles obtained by coupling silicon dioxide to 100 parts by weight of Shirasu balloon, it is possible to impart water repellency and increase mechanical strength.

Next, a method for preferably manufacturing the inorganic lightweight decorative board of the present invention will be described with reference to the drawings. Figure 1
1A and 1B are structural explanatory views of one embodiment of a molding form used in the present invention, FIG. 1A is a plan view, and FIG. 1B is FIG.
The sectional view on the AA side in (a) is shown. In FIG. 1, reference numeral 1 indicates a mold, and reference numerals 2 and 3 indicate partition members. t'denotes the height of the partition member, and w'denotes the width of the partition member. The interior of the mold 1 is divided into four sections 10, 11, 12, and 13 by partition members 2 and 3. In the present invention, each divided section 10, 11, 12,
As shown in FIG. 2, the surface plate 4 having the upper surface coated with the adhesive 5 is placed in the inside 13. The shape of the face plate corresponds to the shape of the section. In this case, the height t ′ of the partition members 2 and 3
And the thickness T of the surface plate 4 are 0 <t '/ T≤0.
8, preferably 0.1 <t ′ / T ≦ 0.5. In this relational expression, when t '/ T is 0, it is not preferable because the voids are eliminated between the adjacent surface plates in the obtained decorative plate, which makes it impossible to apply the jointing agent in the finishing work. On the other hand, t' When /T>0.8, the depth of the void becomes too large, the bending strength becomes weak, and the portion of the void easily breaks, which is not preferable. Further, in the partition members 2 and 3, the relationship between the thickness T of the surface plate and the width w ′ is 1.5 ≦ T /
It is preferable to maintain the relationship of w'≤10, preferably 4≤T / w'≤10. If T / w ′ is less than 1.5, the bending strength is insufficient when the decorative board is cured, and the decorative board is liable to be damaged by the load of the surface board, which is not preferable. Also,
The veneer will also look luxurious. On the other hand, T / w '
When the value exceeds 10, the dimensional accuracy of the surface plate is severely required, it takes time and labor to process the surface plate, and it becomes difficult to reduce the residual stress generated during curing, and warping and cracking may occur. Is not desirable.

As the adhesive 5 applied to the upper surface of the surface plate 4, polymer adhesives such as epoxy resin and urethane resin can be used, but preferably inorganic adhesives such as
A water glass adhesive is used. This water glass adhesive
A water glass is mixed with a curing agent and, if necessary, inorganic powder is added. Examples of the water glass and the curing agent in this case include those described above. Examples of the inorganic powder include various materials such as kaolin, clay, shirasu, diatomaceous earth, sepiolite, zeolite, silica and mica. From the viewpoint of workability, it is preferable that the viscosity of the water glass adhesive is kept higher than the viscosity of water glass containing a curing agent used in the production of the above-mentioned lightweight plate. Others, more preferably an alumina-based adhesive,
Silica-based, silica-alumina-based, and magnesia-based inorganic adhesives are used. The amount of adhesive applied varies depending on the viscosity and adhesive strength of the adhesive, but when an alumina-based inorganic adhesive is used, the amount applied is 300 to 500 g / m ² .

As shown in FIG. 3, a mixture of water glass, a curing agent and an inorganic aggregate is formed on the adhesive application surface 5 of the face plate 4 placed in each divided section as described above. The resulting molding material 6 is filled in layers and pressure-molded at room temperature or under heating. After pressure molding, it is preferable to take out the obtained molded product from the molding frame and cure the pressure molded product at room temperature or under heating. In this pressure molding, the molded product can be cured in the molding frame, but since the pressure molded product is a solid substance and is easy to handle,
It is preferable to take out the molded product from the molding frame and hold it at room temperature or under heating to cure it. The pressure at the time of pressure molding is 0.05 to 15 kg / cm ² G, preferably 3
~ 12 kg / cm ² G. When the molded product is cured under heating, a temperature condition of 30 ° C. or higher, preferably 80 ° C. or lower is adopted, and the curing time is usually at a relative temperature of 40 to 40 ° C.
It is 1 to 3 hours under the condition of 80%. The heat-cured product of the molded product can be used as a product as it is, but in order to further advance the curing reaction and improve the mechanical strength, it is a constant temperature selected at or near room temperature and at a relative temperature of 40 to 100%. 14 to 90 days under conditions, preferably 30 to 60
It is preferable to keep it for about a day before use.

FIG. 4 is a structural explanatory view of the inorganic lightweight decorative board 20 obtained as described above. FIG. 4A shows a plan view thereof, and FIG. 4B shows a sectional view thereof. In FIG. 4, 4
Is a surface plate, 5 is an adhesive layer, 21 is a void, and 22 is an inorganic lightweight plate. In the inorganic lightweight decorative board 20 of the present invention, a groove-shaped void portion 21 exists between the adjacent surface plates 4. The depth t in the void portion 21 corresponds to the height t ′ of the partition members 2 and 3 shown in FIG. 1, and the width w of the void portion 21.
Corresponds to the width w'of the partition members 2 and 3 shown in FIG. Therefore, the following relationship is established between the depth t of the void in the inorganic lightweight decorative board 20 and the thickness T of the surface board 5. O <t / T ≦ 0.8 (1) Further, the following relationship is established between the thickness T and the width w of the surface plate. 1.5 ≦ T / w ≦ 10 (2) In the inorganic lightweight decorative board 20 of the present invention, the total thickness thereof is 10 to 100 mm, preferably 10 to 40 mm, and the thickness of the adhesive layer 5 is 0.05. Is about 2 mm, the thickness of the surface plate is 10 to 50% of the total thickness,
Usually, it is preferable to set it in the range of 3 to 20 mm.

FIG. 5 is a structural explanatory view of another embodiment of the molding form used in the present invention. FIG. 5 (a) is a plan view and FIG. 5 (b) is A- in FIG. 5 (a). The A'sectional view is shown. The formwork shown in FIG. 5 has partition members 25 and 26 respectively arranged on its two vertical and horizontal side edges, and otherwise has the same structure as that shown in FIG. The inorganic lightweight decorative board in the case of using the molding frame shown in FIG. 5 can be manufactured in the same manner as in the case of using the frame shown in FIG. FIG. 6 is a structural explanatory view of an inorganic lightweight decorative board obtained by using the mold shown in FIG. FIG. 6A shows a plan view thereof, and FIG. 6B shows a sectional view thereof. In FIG. 6, 4 is a surface plate, 5 is an adhesive layer, 21 is a void formed between adjacent surface plates, and 22 is an inorganic lightweight plate.
Further, reference numeral 27 denotes a void portion formed on the vertical and horizontal side edges of the decorative plate. Since this inorganic lightweight decorative board shown in FIG. 6 has voids 27 formed in the vertical and horizontal side edges thereof,
When arranging a plurality of them in a plane, the void 27
It is possible to easily finish it into a single flat plate-like shape only by vacantly matching the side end surface having the gap and the side end surface having no void 27. FIG. 7 shows a structure explanatory view of the decorative plates arranged in parallel in this way. FIG. 7A is a plan view thereof, and FIG.
Shows the sectional view.

In the method for producing the inorganic lightweight decorative board as described above, there is an advantage that the production of the inorganic lightweight board and the laminating and adhesion of the surface board to the inorganic lightweight board can be carried out at the same time, and the resulting inorganic board is obtained. The lightweight decorative board has an advantage that the adhesive strength between the surface board and the inorganic lightweight board is large and interface peeling hardly occurs. Further, in the above method, there is no influence of the product thickness due to the variation in the thickness of the decorative plate, a uniform product can be obtained, and a decorative plate including a plurality of surface plates can be obtained by one press molding, so that productivity is improved. There is a big advantage that is high. In addition, since groove-like voids are formed on the surface of the product, finishing work (joint application) is simplified, and further relaxation of press compression residual stress is promoted, which is also effective in preventing warpage. Is.

The inorganic lightweight decorative board of the present invention can also be manufactured by laminating and adhering a surface board to an inorganic lightweight board which has been formed in advance through an adhesive layer. In this case, as the inorganic lightweight plate, a plurality of surface plates can be laminated and adhered through a predetermined gap portion, and the surfaces thereof have a width w ′ and a height t ′ so that the surface corresponds to the shape of the surface plate. The one that is divided into a plurality by the convex portion is used. Then, a surface plate having an adhesive applied to the lower surface is laminated and adhered to each of the sections formed on the inorganic lightweight plate. Further, such an inorganic lightweight plate having a convex portion on the surface is a mold frame shown in FIGS. 1 and 5 in which a concave portion is formed in a portion corresponding to the partition member on the surface of the bottom plate. It can be obtained by using it, filling it with a molding material, and press-molding.

[0018]

INDUSTRIAL APPLICABILITY The inorganic lightweight decorative board of the present invention is light in spite of being composed mainly of an inorganic substance, and is excellent in aesthetic appearance because its surface is formed like a natural stone. It has the feature. The inorganic lightweight decorative board of the present invention is composed of a plurality of surface boards, and since the voids are present between the adjacent surface boards, the application of the jointing agent between the adjacent surface boards is facilitated and the warp is prevented. The occurrence of is prevented. Furthermore, since the inorganic lightweight decorative board of the present invention is a large-sized one composed of a plurality of surface boards and the thickness of the decorative board can be made uniform, it is easy and efficient to apply it to a solid surface such as a wall or floor. Since it does not require special skill, even a person other than a mason can easily perform the pasting work. Since the method for manufacturing an inorganic lightweight decorative board of the present invention does not include a firing step, it can be carried out with simple equipment and at low cost. Moreover, according to the present invention, since a product including a plurality of surface plates can be produced at one time, the productivity of the decorative plate is also excellent.

[0019]

EXAMPLES Next, the present invention will be described in more detail by way of examples. In addition, all parts and% shown below are based on weight.

Examples 1 to 16 15 parts of a hardening agent (condensed aluminum phosphate) was mixed with 100 parts of JIS No. 3 water glass, and further 12 parts of rough shirasu powder, 8 parts of mica and 1 kaolin were used as inorganic powder.
0 parts were compounded and uniformly mixed to prepare a water glass adhesive A. Further, in 128 parts of JIS No. 3 water glass, 18 parts of a curing agent (condensed aluminum phosphate), 8.4 parts of rough shirasu powder, 5.6 parts of mica, 5.6 parts of kaolin and reinforcing fiber (vinylon fiber) 1. 5 parts of latex and 4.5 parts of latex were mixed and uniformly mixed to prepare a water glass adhesive B. Further, as the shirasu balloon, the particle size is 180 to 42.
A mixture of 100 parts of 0 μm and 50 parts of a particle size of 38 μm or less was used. The molding frame used had the structure shown in FIG. In this case, the size of the mold 1 is
Vertical: (600 + 4w ') mm, Horizontal: (600 + 4w')
mm, height: 100 mm, partition members 2, 3 and 2
Each width w'and height t'of 6 are as shown in Table 1. Next, a water glass adhesive A is applied to the entire surface of one side of a marble plate having a thickness T = 10 mm to a thickness of about 0.5 mm, and the applied surface is faced up to each section 10, 11, 12, 13 of the formwork. Place it. Then, a mixture A of 150 parts of shirasu balloon and 177.6 parts of water glass adhesive B was filled in a mold, and a pressing plate was placed on the mold A, and the pressure was 10 kg / cm ² G for 25 m.
After pressurizing to m thickness, the molded product (decorative board) is taken out from the mold, heat-cured for 3 hours in an oven at 40 ° C, and the resulting decorative board is left at room temperature of about 25 ° C for 7 days. did. Thus, an inorganic lightweight decorative board having the structure shown in FIG. 6 was obtained. About this thing, the thickness, the bulk density, etc. were measured. The results are also shown in Table 1. The inorganic lightweight decorative board of the present invention showed a good appearance without interfacial peeling. In Examples 4 to 6, an alumina-based inorganic adhesive (manufactured by Showa Polymer Co., Ltd .: Hyper Random (R) C-989) was used instead of the adhesive A. Both the adhesive A and the alumina-based inorganic adhesive could be used without any problem, but the adhesive A showed a tendency to be somewhat inferior in adhesive strength to the adhesive B.

[0021]

[Table 1]

[Brief description of drawings]

FIG. 1 is a structural explanatory view of one embodiment of a molding form. FIG. 1A: Plan view FIG. 1B: AA ′ cross-sectional view of FIG.

FIG. 2 is a view showing a state in which a surface plate having an upper surface coated with an adhesive is placed in the divided sections of the molding frame of FIG.

3 is a state diagram in which a molding material made of a mixture of an inorganic aggregate, water glass and a water glass curing agent is filled in the molding frame of FIG.

FIG. 4 is a structural explanatory view of an inorganic lightweight decorative board of the present invention manufactured by using the molding frame of FIG. 1. Figure 4 (a): Plan view Figure 4 (b): Sectional view

FIG. 5 is a structural explanatory view of another embodiment of the molding frame. FIG. 5A: Plan view FIG. 5B: AA ′ cross-sectional view of FIG.

6 is a structural explanatory view of an inorganic lightweight decorative board of the present invention manufactured using the molding frame of FIG. 5. FIG. FIG. 6A: Plan view FIG. 6B: Cross sectional view

7 is an explanatory diagram of a case where the inorganic lightweight decorative boards of FIG. 6 are arranged in parallel. FIG. 7A: Plan view FIG. 7B: Cross-sectional view

[Explanation of symbols]

 1 Molding Form 2, 3, 26 Partitioning Member 4 Surface Plate 5 Adhesive Layer 6 Molding Material 10-13 Divided Section 20 Inorganic Lightweight Decorative Board 21, 27 Void 22 Inorganic Lightweight Board

Claims (3)

[Claims] 1. An inorganic lightweight plate having a thickness of 7 to 90 mm formed from a mixture of an inorganic aggregate containing shirasu balloon as a main component, water glass and a water glass curing agent, and a plurality of laminated and adhered layers thereon. And a natural stone plate or a natural stone-like plate having a thickness of 3 to 20 mm. Between the adjacent natural stone plates or natural stone-like plates, voids satisfying the following formulas (1) and (2) are interposed. Inorganic lightweight decorative board. O <t / T ≦ 0.8 (1) 1.5 ≦ T / w ≦ 10 (2) (where T is the thickness of the natural stone plate or the natural stone-like plate, t
Indicates the depth of the void, and w indicates the width of the void.) 2. The inorganic lightweight decorative board according to claim 1, wherein an adhesive layer made of an alumina-based inorganic adhesive is interposed between the inorganic lightweight board and the natural stone board or the natural stone-like board. 3. A natural stone having a planar shape corresponding to the planar shape of the compartments in each compartment of a formwork whose interior is divided into a plurality of compartments by a partition member satisfying the following formulas (1) and (2). A plate or a natural stone-like plate is placed by applying an adhesive on its upper surface, and the inorganic aggregate mainly composed of shirasu balloon whose surface is coated with water glass containing a curing agent is layered on the adhesive-coated surface. Laminate, pressurize at room temperature or under heat,
A method for producing an inorganic lightweight decorative board, which comprises reacting the curing agent with water glass. O <t '/ T≤0.8 (1) 1.5≤T / w'≤10 (2) (where T represents the thickness of natural stone or natural stone-like plate,
(t 'indicates the height of the partition member, and w'indicates the width of the partition member)