JPH10266366A - Moisture absorbing and releasing material and room humidity control method employing moisture absorbing and releasing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a moisture absorbing and releasing material capable of readily controlling room humidity laminating a moisture absorbing and releasing layer formed of a hardened inorganic composition consisting mainly of SiO2 -Al2 O3 powder or the like on the side surface of a base material. SOLUTION: A moisture absorbing and releasing layer 2 formed by hardening an inorganic composition consisting mainly of SiO2 -Al2 O3 powder, alkali metal silicate and water is laminated on at least one side surface of the base material 3 for forming a moisture absorbing and releasing material 1. Then, the moisture absorption and releasing layer 2 side is put at the room wall surface side in order to form a wall surface for surrounding the room with the moisture absorbing and releasing material 1. As such, the moisture absorption and releasing layer 2 functions to absorb room moisture or release moisture in the room in accordance with the fluctuations of room humidity. Accordingly, only by using mechanical control means at a minimum, a room atmosphere can be maintained in a pleasant humidity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moisture absorbing / releasing material and a humidity control method using the moisture absorbing / releasing material.

[0002]

2. Description of the Related Art As a method of adjusting the humidity in a room, there is a method of using a device such as a dehumidifier or a humidifier. However, this method requires securing a space for installing the device, and also requires initial setting of the device. There are problems such as high costs and running costs. Therefore, an interior material disclosed in JP-A-8-42110 in which particles having hygroscopicity such as silica gel AB type are dispersed in a cement-based substrate such as gypsum or cement, No. 1926 discloses a coating material comprising a coating composition in which a hydraulic material such as cement is added with an inorganic salt such as montmorillonite and calcium chloride. I have.

However, in the case of the above-mentioned interior materials having moisture absorption and desorption properties, there are problems in strength such as surface strength, impact resistance, bending strength and the like, and handling during transportation and construction and durability after construction are difficult. There is a problem with sex. Moreover, in the case of the interior material using the silica gel AB type as the moisture absorbing / releasing particles, the moisture absorbing performance was not sufficient.

[0004]

SUMMARY OF THE INVENTION In view of such circumstances, the present invention provides a moisture-absorbing and desorbing material which is excellent not only in moisture absorption and desorption properties but also in handleability during construction and durability after construction. It is an object of the present invention to provide a humidity control method using a moisture absorbing and releasing material.

[0005]

Means for Solving the Problems] The present invention in such absorbing Shimezai, in order to achieve the above object, SiO ₂ -Al
_The moisture absorbing / releasing layer formed by curing an inorganic composition mainly composed of ₂ O ₃ -based powder, alkali metal silicate and water was laminated on at least one side surface of the substrate.

The SiO ₂ —Al ₂ O ₃ powder includes SiO ₂ : Al ₂ O ₃ = 1: 9 to 9: 1 (weight ratio).
And the powder as a whole is SiO
It is desirable that the total content of ₂ and Al ₂ O ₃ be 50% by weight or more. That is, if the content is less than 50% by weight, the reactivity with the aqueous alkali metal silicate solution is reduced, and the strength of the obtained moisture absorbing / releasing layer may be reduced.

[0007] Such SiO ₂ -Al ₂ O ₃ -based powders include, for example, the following, which can be used alone or in combination. Fly ash containing at least 80% by weight of particles having a particle size of 10 μm or less

[0008] Decolorized fly ash containing 80% by weight or more of particles having a particle size of 10 µm or less Inorganic powder obtained by melting fly ash or clay and spraying it into a gas

The inorganic powder obtained by further heating the inorganic powder obtained by applying mechanical energy of 0.1 to 30 kwh / kg to the clay at 100 to 750 ° C.

[0010] 0.1 to 30 kwh /
Inorganic powder obtained by applying kg of mechanical energy Ash of electric precipitator during production of corundum or mullite

Crushed calcined bauxite metakaolin

Incidentally, ordinary fly ash is defined in JIS.
A The fine ash particles collected by a dust collector from a pulverized coal combustion boiler specified in A6201 have a SiO ₂ content of 40% or more, a moisture content of 1% or less, a specific gravity of 1.95 or more, and a specific surface area of 270.
It passes through a standard sieve of 0 cm ² / g or more and 44 μm or more by 75% or more. Then, fly ash is a method of classifying this normal fly ash using a commonly used classifier such as wet sedimentation classification, air classification, specific gravity separation, and fine milling such as a jet mill, a roll mill, and a ball mill. It can be obtained by processing by a conventionally known method such as a method of pulverizing also using a mill, a method of using a continuous system of a classifier and a pulverizer, and the like.

The reason that the particles having a particle size of 10 μm or less must be contained in an amount of 80% by weight or more, like fly ash, is that if the amount of the fly ash having a particle size of 10 μm or less is less than 80% by weight, the alkali metal silicate This is because the reactivity with the salt aqueous solution is reduced, and there is a possibility that the strength is reduced or curing failure is caused.

The above-mentioned decolorized fly ash is obtained by baking fly ash at 400 to 1000 ° C. or baking ordinary fly ash at 400 to 1000 ° C.
Can be obtained in the same manner as fly ash.
That is, fly ash is generally black, and if this black fly ash is fired at a temperature of 400 ° C. or higher as described above, it can be decolorized. However, when firing at a temperature exceeding 1000 ° C., the reactivity with the aqueous solution of the alkali metal silicate decreases, so firing at the above temperature range is desirable.

[0015] The inorganic powder is obtained by melting fly ash or clay and spraying it into a gas.
As a method of melting and spraying in a gas, a spraying technique applied to a ceramic coating, preferably a spraying technique in which the fly ash and clay are melted at a temperature of 2000 to 16000 ° C and sprayed at a speed of 30 to 80 m / s. ,
Specifically, a plasma spraying method, a high energy gas spraying method, an arc spraying method, and the like can be given.

The specific surface area of the inorganic powder obtained by the above thermal spraying technique is generally controlled to 0.1 to 60 m ² / g.

The above-mentioned inorganic powder and the clay used as a raw material of the inorganic powder include SiO ₂ as a chemical composition;
Clay containing 5 to 85% by weight, Al ₂ O ₃ ; 90 to 10% by weight, for example, kaolinite, dickite, nacrite, kaolin minerals such as halloysite, muscovite, illite, fengite, sea chlorite, celadonite, Mica clay minerals such as paragonite and branmarite, montmorillonite, beidellite, nontronite, sabonite,
Examples include smectites such as saconite, chlorite, pyrophyllite, talc, and sand shale.

The mechanical energy used in the production of the inorganic powder refers to a compressive force, a shearing force and an impact force, which may be used alone or in combination of two or more. . Examples of the equipment for making these act specifically include a ball mill, a vibration mill, a planetary mill, a medium stirring type mill, a roller mill, a mortar, and a jet powder crusher.

The particle diameters of the clay and metakaolin used in the production of the above inorganic powders are not particularly limited.
The average particle diameter is preferably from 0.01 to 500 μm, more preferably from 0.1 to 500 μm, in order to effectively exert mechanical energy.
It is preferably from 1 to 500 μm, particularly preferably from 0.1 to 1 μm.
00 μm.

When the mechanical energy applied during the production of the inorganic powder is less than 0.1 kwh / kg, the reactivity of the obtained inorganic powder with the aqueous alkali metal silicate solution is reduced, and If it exceeds, the load on the above-mentioned crushing device increases, and the wear and damage of the device increase,
Since problems such as impurities to the above-mentioned clay occur, 0.1 to
Limited to 30 kwh / kg, preferably 1.0 to 26
Act at kwh / kg.

The reason why the mechanical energy applied to metakaolin is limited to 0.1 to 30 kWh / kg is the same as in the above cases. When applying mechanical energy, a grinding aid may be added as necessary.

The pulverizing auxiliary agent prevents clay or metakaolin powder from adhering to the inside of the device or remarkably agglomerating when mechanical energy is applied. Examples thereof include alcohol amines such as triethanolamine, metal soaps such as sodium stearate and calcium stearate, and acetone vapor. These may be used alone or in combination of two or more.

The inorganic powder is obtained by applying steam mechanical energy to the clay and then heating the clay to a temperature of 100 to 750 ° C., because the mechanical strength is improved by heating. If the heating temperature is lower than 100 ° C., no improvement in strength is observed. If the heating temperature is higher than 750 ° C., crystallization of the inorganic powder occurs, and the reactivity with respect to the alkali metal silicate aqueous solution decreases. Limited, preferably limited to 200-600 ° C. When the heating time is short, the mechanical strength of the obtained moisture absorbing / releasing layer is small, and when the heating time is long, the energy cost increases. Therefore, 1 minute to 5 hours is desirable.

And the inorganic powders are disclosed in
060 and Japanese Patent Publication No. 4-45471. The commercially available metakaolin can be used.

The alkali metal silicate used in the present invention is a silicate represented by M ₂ O · nSiO ₂ (at least one metal selected from M = K, Na and Li), When the value is small, a moisture-absorbing / desorbing layer having a good appearance cannot be obtained, and when the value is large, gelation easily occurs.
1 to 8, more preferably 0.5 to 2.5. Further, since the alkali metal silicate aqueous solution can further improve the moisture absorption / desorption property, it is preferable that the alkali metal is potassium or a mixture of potassium and another alkali metal.

The alkali metal silicate is preferably added in the form of an aqueous solution. Further, when the aqueous solution is used, when the concentration is low, the reactivity with the SiO ₂ —Al ₂ O ₃ powder is reduced, and when the concentration is high, the alkali metal salt is easily formed. %, More preferably 10 to 60% by weight. That is,
When the concentration is lower than 10% by weight, the strength of the obtained moisture absorbing / releasing layer is reduced. When the concentration is higher than 70% by weight, the viscosity of the alkali metal silicate aqueous solution is increased, and the workability at the time of mixing and molding is reduced. May drop.

The aqueous alkali metal silicate solution may be prepared by dissolving the alkali metal silicate in water as it is under pressure and heating.
The iO ₂ component may be dissolved under pressure and heat so that n becomes a predetermined amount, or a commercially available aqueous solution of an alkali metal silicate is used after being adjusted to a predetermined composition with a metal hydroxide and water. You may.

The added amount of the alkali metal silicate is SiO ₂ −
The amount is preferably 1 to 300 parts by weight (10 to 1300 parts by weight as an aqueous solution) based on 100 parts by weight of the Al ₂ O ₃ powder.
0 to 250 parts by weight (10 to 1000 parts by weight as an aqueous solution) is more preferable. That is, if the added amount is too large, cracks and the like may be generated in the moisture absorbing / releasing layer.

The water used in the present invention may be added in a total amount as an aqueous solution of an alkali metal silicate, or may be added in the form of both an aqueous solution of an alkali metal silicate and independent water. . If the amount of water is too small, it will not cure sufficiently, and if it is too large, the strength of the moisture absorbing / releasing layer will decrease.
10 to 10 parts by weight of SiO ₂ —Al ₂ O ₃ powder
1000 parts by weight, preferably 10 to 750 parts by weight, more preferably 50 to 500 parts by weight.

In the inorganic composition of the present invention, a hygroscopic filler, an inorganic filler, a reinforcing fiber,
Light aggregates, pigments, foaming agents, foaming aids, foaming agents and the like can be added. In particular, by adding a hygroscopic filler, the hygroscopicity can be further improved.

Examples of the hygroscopic filler include inorganic hygroscopic materials such as zeolite, diatomaceous earth, sepiolite and calcium chloride, and water-soluble polymers such as polypinyl alcohol (PVA), glycerin and diethylene glycol.
These are used singly or as a mixture, and those having excellent hygroscopicity as well as hygroscopicity, such as zeolite, are preferable.

The amount of the moisture-absorbing filler added is SiO ₂ -Al
_{The amount} is preferably from 1 to 150 parts by weight based on 100 parts by weight of the ₂ O ₃ powder. That is, if the amount is less than 1 part by weight, the effect of the addition is not obtained.

As the inorganic filler, rock powder, volcanic ash (silas, anti-firestone, etc.), wollastonite, calcium carbonate, silica stone powder, mica, mica, silica fume and the like can be used. The amount _is preferably 900 parts by weight or less with respect to SiO 2 -Al ₂ O ₃ -based powder 100 parts by weight. If the amount exceeds 900 parts by weight, the mechanical strength may be reduced.

As the reinforcing fibers, those used in ordinary cement products can be used, and polypropylene, vinylon, rayon, alkali-resistant glass, carbon, acrylic,
Fibers such as aramid and acrylonitrile can be used alone or in combination. Fiber diameter is 1 ~ 500μ
m and a fiber length of 1 to 15 mm are desirable. That is, if the fiber diameter is less than 1 μm, a fiber ball is formed during mixing,
When the strength exceeds 500 μm or the fiber length is less than 1 mm, a reinforcing effect such as improvement in tensile strength cannot be expected. On the other hand, if the fiber length exceeds 15 mm, the dispersibility decreases, and a moisture absorbing / releasing layer having uniform strength cannot be obtained.

As the amount of the reinforcing fiber, SiO ₂ -A
It is desirable that the content be 10 parts by weight or less based on 100 parts by weight of the l ₂ O ₃ powder. If it exceeds 10 parts by weight, the dispersibility of the fiber may be reduced.

As the lightweight aggregate, inorganic foams such as pearlite, glass balloon, silica balloon, fly ash balloon and shirasu foam, and organic foams such as phenol resin, urethane resin, polyethylene and polystyrene can be used. The amount of the lightweight aggregate added is SiO ₂ −
It is desirable that the amount be 150 parts by weight or less based on 100 parts by weight of the Al ₂ O ₃ -based powder. If the amount exceeds 150 parts by weight, there is a possibility that the strength, surface smoothness or molding workability may be reduced.

As the pigment, metal oxide pigments such as iron oxide, titanium oxide and cobalt oxide and carbon black are desirable. The addition amount of the pigment with _respect to SiO 2 -Al ₂ O ₃ -based powder 100 parts by weight or less is preferable 50 parts by weight.
Even if it exceeds 50 parts by weight, the hiding power is not improved and it is uneconomical.

As the foaming agent, Mg, Ca, Cr, M
n, Fe, Co, Ni, Cu, Zn, Al, Ga, S
n, Si, metal powders such as ferrosilicon, hydrogen peroxide water or sodium peroxide, potassium peroxide, peroxide powders such as sodium perborate, and the like, cost, safety,
Considering availability and ease of mixing, Al and hydrogen peroxide are preferred.

The foaming agent powder preferably has a particle diameter of 1 to 200 μm. That is, if the particle diameter is smaller than 1 μm, the dispersibility is reduced, and rapid foaming is caused. If the particle diameter is larger than 200 μm, the reactivity may be reduced. The addition amount of the foaming agent (solution 100% basis), compared SiO ₂ -Al ₂ O ₃ -based powder 100 parts by weight or less is preferable 5 parts by weight. That is, if the amount exceeds 5 parts by weight, the strength is remarkably reduced, and the molded article cannot be handled.

As foaming agents, higher alcohol sulfates, alkyl ether sulfates, aromatic derivative sulfonates, imidazoline derivatives, fatty acid amides,
Animal protein systems can be used. The addition amount of the foaming agent is S
It is desirable that the content be 10 parts by weight or less based on 100 parts by weight of the iO ₂ -Al ₂ O ₃ powder. If the amount is more than 10 parts by weight, poor curing tends to occur.

Examples of the foaming aid include porous powders such as silica gel, zeolite, activated carbon, and alumina gel, and metal soaps such as metal stearate and metal palmitate. The addition amount of the foaming aid is SiO ₂ —Al ₂ O
10 parts by weight or less is desirable for 100 parts by weight of the ₃ series powder. If the amount is more than 10 parts by weight, there is a possibility that bubbles may be broken.

In order to obtain the above-mentioned inorganic composition by mixing, an ordinary mixer such as a paddle rotary mixer, an oscillating mixer or a screw mixer can be used. As a mixing method, a powder raw material is dry-mixed, and an alkali metal silicate aqueous solution is further added to the obtained mixture and mixed, a method of simultaneously supplying and mixing all the raw materials, an alkali metal silicate aqueous solution And a method in which a part of the raw material is mixed, and the remaining raw materials are sequentially added and mixed.

When a foaming agent is used, mixing at the end of the mixing step is advantageous in terms of workability and bubble stability. When a foaming agent is used, a method in which the foaming agent is added last, or a slurry is made from a raw material other than the foaming agent, and mixed with an aqueous solution in which bubbles are generated by the foaming agent and water is preferable. Foaming agent concentration of 0.1 to 5 when used as an aqueous solution
% Is desirable. If it is less than 0.1%, the stability of the foam is inferior and the foam breaks, and if it is more than 5%, poor curing occurs.

The substrate is not particularly limited, and examples thereof include a cement sheet, a gypsum board, and a wood board. The method of laminating the substrate and the moisture absorbing / releasing layer is not particularly limited. For example, a method of applying a slurry-like inorganic composition for forming a moisture absorbing / releasing layer on the surface of the substrate, a slurry-like inorganic composition in a mold, A method of curing the inorganic composition in a state where the material is filled by the thickness of the moisture absorbing and releasing layer and the substrate is placed on the filled inorganic composition, a cured product of the inorganic composition to be the moisture absorbing and releasing layer in advance And then laminating the cured body and the substrate via an adhesive.

The filling of the inorganic composition slurry into the mold may be carried out by a free-fall method or may be carried out by a pump or the like. Vibration may be applied during or after filling the slurry for leveling or defoaming the slurry. When the viscosity of the slurry is high, press molding may be performed. The mold is not particularly limited, and includes metal, resin, rubber, and the like as materials. If an irregular pattern is formed on the mold surface, it is possible to absorb and release a surface shape excellent in decorativeness according to the irregularity of the mold surface. Wet material can be obtained.

The condition for curing the inorganic composition is preferably such that the ambient temperature is maintained at a temperature between room temperature and 100 ° C. for 5 minutes to 12 hours. The heating method is not particularly limited,
For example, an oven is mentioned. It goes without saying that the higher the heating temperature, the shorter the curing time. When the heat curing is completed, the mold is released. The shape of the moisture absorbing and releasing material is not particularly limited, and examples thereof include a panel shape and a tile shape.

On the other hand, in the humidity control method according to the present invention, the moisture-absorbing / desorbing material of the present invention is disposed along at least a part of the wall constituting the room, with the moisture-absorbing / desorbing layer facing the indoor surface. I made it. In the above method, the wall surface constituting the room includes not only an elevation wall but also a ceiling, a floor, an entrance door, and the like.

The arrangement along the part is not particularly limited. For example, a method of directly laying a moisture absorbing and releasing material in the form of a panel or a tile as a wall may be used.

[0049]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of a moisture absorbing and releasing material according to the present invention. As shown in FIG. 1, the moisture absorbing / releasing material 1 has a moisture absorbing / releasing layer 2 on one side surface of a substrate 3.
Are laminated.

The moisture absorbing / releasing layer 2 is formed of an inorganic composition mainly composed of an SiO ₂ —Al ₂ O ₃ powder, an aqueous solution of an alkali metal silicate containing at least potassium as an alkali metal, and formed into a panel. And the surface is decorated. The base material 3 is formed from a gypsum board or a cement sheet.

Since the moisture absorbing and releasing material is configured as described above, if the moisture absorbing and releasing material 1 is used to form a wall surrounding the room with the moisture absorbing and releasing material 2 facing the indoor wall surface, Absorbs indoor humidity when indoor humidity is high and lowers indoor humidity, and when indoor humidity is low, moisture absorbed in the moisture absorbing and releasing layer 2 is diffused into the room and raises indoor humidity. Let it.

Therefore, the indoor atmosphere can be maintained at a comfortable humidity by using only a minimum of mechanical adjustment means. Further, since the moisture absorbing / releasing layer 2 is formed of a cured body of the above-mentioned inorganic composition, the hardness is high and the durability is excellent. Moreover, the moisture absorbing / releasing layer 2 also has a deodorizing effect.

[0053]

Embodiments of the present invention will be described below in more detail.

Example 1 Metakaolin (Engelher)
Product name: SATENTONE SP33, average particle size 3.3μ
m, BET specific surface area: 5.8cm^Two/ g) 100 parts by weight and
Triethanolamine 25% by weight and ethanol 75% by weight
0.5 part by weight of the mixed solution of Ultra Fine Mill
(Mitsubishi Heavy Industries, use zirconia ball 10mm, ball
(Filling rate: 85% by volume) and 10kwh / kg of mechanical energy
With the action of luggie, SiO_Two-Al_TwoO _ThreeSystem powder
Was. The applied mechanical energy is
The power supplied to the Rafine mill is divided by the unit weight of the treated powder.
It appeared.

The thus obtained SiO ₂ —Al ₂ O ₃
100 parts by weight of base powder, 20 parts by weight of mica as inorganic powder (M-100 manufactured by Repco), 30 parts by weight of talc (Takul S manufactured by Nippon Talc), wollastonite (Chemolit A-60 manufactured by Tsuchiya Kaolin) ) 57.5 parts by weight and vinylon fiber as a reinforcing fiber (RM182 manufactured by Kuraray Co., Ltd.)
-3) 0.5 parts by weight was supplied to an Erich mixer and dry-mixed for 5 minutes to obtain a mixed composition A.

100 parts by weight of the mixed composition A and an alkali metal silicate aqueous solution (manufactured by Nippon Chemical Industrial Co., Ltd. [SiO ₂ : 25
%, Na ₂ O: 17%, water: 58%] of those) fed in 75 parts by weight and the Omni Mixer (manufactured by Chiyoda Giken Kogyo Co., Ltd.), and mixed for 2 minutes to obtain a slurry of mineral composition. This slurry-like inorganic composition is applied to a cement paperboard (thickness: 10 mm, specific gravity: 1.2) as a base material so as to have a thickness of 2 mm. The composition was cured to obtain a moisture absorbing / releasing material having a moisture absorbing / releasing layer formed on one side surface of the substrate with a thickness of 2 mm.

Example 2 A gypsum board (manufactured by Yoshino Gypsum Co., thickness 15 mm, specific gravity 0.8) was used as a base material.
A moisture absorbing / releasing material was obtained in the same manner as in Example 1.

The moisture absorbing and releasing material obtained in the above Examples 1 and 2 was used as the base material in the cement papermaking board used as the base material in Example 1 as Comparative Example 1, and as the base material in Example 2 as Comparative Example 2. Gypsum board, a commercially available moisture-absorbing and desorbing board (manufactured by Daiken Kogyo Co., Ltd.) as Comparative Example 3 were each sampled into a size of 100 × 100 mm, and the cut side surfaces were sealed with a sealing agent. Each sample was placed in a thermo-hygrostat. Suspended, 90% RH for 24 hours while keeping the temperature and humidity inside the thermo-hygrostat at 25 ° C → 5
0% RH for 24 hours → 90% RH for 24 hours
The change in weight of the sample was measured by repeating low humidity, and the result is shown in FIG.

From FIG. 2, it can be seen that the moisture absorbing / releasing material of the present invention has the same moisture absorbing / releasing properties as a commercially available moisture absorbing / releasing board, and has superior moisture absorbing / releasing properties as compared with a gypsum board or a papermaking slate board. I understand well.

Further, the moisture absorbing and releasing materials obtained in Examples 1 and 2, the cement sheet of Comparative Example 1, the gypsum board of Comparative Example 2, and the moisture absorbing and releasing board of Comparative Example 3 were attached to the surface side (inside of the room). Hardness) (Vickers hardness meter MVK-50 manufactured by Akashi Seisakusho)
0 g) and the results are shown in Table 1.

[0061]

[Table 1]

From Table 1 above, it can be clearly seen that the moisture absorbing / releasing material of the present invention has a high surface hardness and excellent durability. Further, the moisture absorbing and releasing materials of Example 1 and Example 2 were also confirmed to have deodorizing properties.

[0063]

The moisture absorbing and releasing material according to the present invention is excellent in moisture absorbing and releasing properties because it is configured as described above. In addition, it is excellent in handleability during construction and transport and durability after construction. And if this moisture absorbing and releasing material is arranged along at least a part of the wall surface constituting the room, the humidity of the indoor atmosphere can be adjusted without using equipment such as a dehumidifier or a humidifier. It can be carried out.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an embodiment of a moisture absorbing and releasing material according to the present invention.

FIG. 2 is a comparison graph of the moisture absorbing and releasing performance of the moisture absorbing and releasing materials of Examples 1 and 2 and the building materials of Comparative Examples 1 to 3.

[Explanation of symbols]

 1 moisture absorbing and releasing material 2 moisture absorbing and releasing layer 3 substrate

Claims (2)

[Claims] 1. A moisture absorbing / releasing layer formed by curing an inorganic composition mainly composed of SiO ₂ —Al ₂ O ₃ powder, an alkali metal silicate and water is provided on at least one side surface of a substrate. Absorbing and releasing moisture material. 2. A method for adjusting the humidity in a room, wherein the moisture-absorbing / desorbing material according to claim 1 is disposed along at least a part of a wall surface constituting the room, with the moisture-absorbing / desorbing layer facing the indoor surface.