JPH06321609A - Production of moisture adjusting building material - Google Patents

Abstract

PURPOSE:To restrain a variation of humidity in a space with a building material composing the space. CONSTITUTION:A mixture consisting of fine powder zeolite having <=30mum in the particle size, lime and water, is molded into a desired shape and the molding is kept at 130-180 deg.C in an autoclave to make the zeolite and the lime to cause a hydrothermal reaction, thus the building material is produced. The zeolite quantity compounded in the mixture is adjusted to as to persist unreacted zeolite not consumed by the hydrothermal reaction in the product building material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a humidity control building material capable of naturally controlling the humidity in a room and a building space.

[0002]

2. Description of the Related Art Conventionally, construction materials in Japan have been made by comprehensively using materials having a natural humidity control function such as natural wood, earth walls, and paper. For this reason, it was equipped with an indoor humidity adjustment function and a condensation prevention function.

However, in recent years, reinforced concrete buildings and the like do not have sufficient humidity control function and dew condensation prevention function, and as a supplementary interior material, the development of new airtight building materials and coating materials, etc. Various obstacles have occurred.

Under these circumstances, research has been conducted on building materials having a humidity control function in the material itself, and one of them is one utilizing the water adsorption / desorption property of zeolite. For example, as a humidity control building material using zeolite, 1987, 6
Kashima Construction Technology Research Institute Annual Report (Sagae and Kazumi), published on March 15, published in JP-A-3-93662 and JP-A-3-109244.

[0005]

Since conventional humidity control building materials using zeolite are those in which granular zeolite is hardened using cement (in some cases, fibers are used as a reinforcing material), the weight becomes heavy. Is not easy to handle and
Processing work on site was not easy.

Further, since the cement paste covers the periphery of the granular zeolite, the moisture absorbing / releasing ability inherent to the zeolite cannot be sufficiently exhibited. In addition, there is also the problem of alkali content scattering due to the use of cement binders.

The present invention is intended to solve such a problem.

[0008]

The present invention has a particle size of 30 μm.
A method for producing a building material in which a kneaded material composed of finely divided zeolite of less than m, lime and water is molded into a desired shape, and the molded product is hydrothermally reacted with zeolite and lime by maintaining the temperature at 130 to 180 ° C in an autoclave. There is provided a method for producing a building material for humidity control, characterized in that the blending amount of zeolite in a kneaded product is adjusted so that unreacted zeolite that is not consumed by the hydrothermal reaction remains in the building material.

Here, the blending amount of finely divided zeolite is adjusted so that the molar ratio (CaO / SiO ₂ ) of zeolite (SiO _{2 in} zeolite) to lime (CaO) is in the range of 0.7 to 0.9. Well, in this kneaded product, 30 parts by weight or less of a hydraulic setting material, 5 parts by weight or less of fibers and / or 75 parts by weight or less of granular zeolite (particle size: 100 parts by weight of lime and finely divided zeolite) : 0.1 to 10 mm) can be appropriately blended.

[0010]

[Function] Since zeolite powder and lime have no hydraulic property, they do not harden even when they are kneaded with water. However, the particle size is 3
Finely divided zeolite of 0 μm or less and lime in the presence of water 1
It was found that the autoclave treatment at 30 ° C. or higher cures by hydrothermal reaction.

That is, if a kneaded material composed of finely divided zeolite having a particle size of 30 μm or less, lime and water is molded into a desired shape and the molded product is kept at a temperature of 130 ° C. or higher in an autoclave, the zeolite and lime are separated. It is cured by hydrothermal reaction and a molded product with stable shape is obtained.

This hydrothermal reaction proceeds better as the zeolite is finer. For this, the particle size is 30μ
It is preferable to use zeolite finely pulverized to m or less.
Kneading fine powder of lime together with the zeolite in the required amount of water,
This kneaded product is molded into a desired shape using a mold or the like, and is charged with or without the mold into an autoclave to cause a hydrothermal reaction.

When the temperature in the autoclave exceeds 180 ° C., the pressure becomes higher than 10 atm, the load on the design of the autoclave device increases, and the strength of the cured body tends to decrease. Since the hydrothermal reaction proceeds sufficiently, the upper limit temperature may be 180 ° C. However, the temperature inside the autoclave must be at least 130 ° C. or higher in order to proceed with this hydrothermal reaction. The preferable temperature range in the autoclave is 150 ° C to 160 ° C.
Is. The conditions for causing this hydrothermal reaction are within the operating condition range of an autoclave curing device for ordinary concrete products (for example, ALC). Therefore, in manufacturing the building material of the present invention, the autoclave curing device for concrete products can be used as it is.

If the zeolite used is in the form of particles having a particle size of more than 30 μm, the reactivity with lime is poor and a stable compact cannot be obtained. Therefore, it is necessary to use finely pulverized zeolite having a size of 30 μm or less. When all of this finely divided zeolite is consumed in the hydrothermal reaction with lime, the water adsorption and desorption properties inherent to the zeolite are lost,
It does not serve as a building material having the moisture adjusting function intended by the present invention. Therefore, it is advisable to adjust the blending amount so that a part of the finely divided zeolite that has been mixed remains unreacted in the cured product.

On the other hand, from the viewpoint that the hydrothermal reaction product of zeolite and lime is used as a molded article, zeolite and lime are used as hardening agents, and other substances are mixed in the molded article to improve the usefulness of the present building material. It can be further enhanced. Typical materials include granular zeolite, hydraulic setting materials, and fibers.

Since the granular zeolite has poor reactivity to hydrothermal reaction as described above, it remains in the hardened body while retaining the water adsorption / desorption property. Therefore, if an appropriate amount of the granular zeolite is blended, it will become a product building material. The humidity control function can be further enhanced. The particle size of the granular zeolite used is 0.1-10.
mm, preferably 0.25 to 3 mm. Further, the blending amount is preferably in the range of 0 to 75 parts by weight with respect to the total 100 parts by weight of finely powdered zeolite and lime.

When the fibers are mixed in the molded product, they serve not only to impair the humidity control function of the product building material but also to increase the strength and also to make the matrix porous. Therefore, even if the amounts of the finely divided zeolite and the granular zeolite are increased, the fiber reinforcing action can maintain sufficient product strength. Further, the zeolite existing in the hardened body can be easily communicated with the atmospheric air, and the moisture absorption / release function originally possessed by the zeolite is improved.

As the fiber, for example, vinylon fiber (PVA
Fibers, polypropylene fibers, plant fibers, carbon fibers and other short fibers (filaments) should be used. The amount of fibers to be mixed is a mixture of finely divided zeolite and lime 10
It may be in the range of 0.7 to 5 parts by weight with respect to 0 parts by weight.
If the amount is less than 0.7 part by weight, the effect of improving the strength is small. On the other hand, if the amount is more than 5 parts by weight, the effect of improving the strength cannot be expected so much. Since plant fiber itself has a humidity control effect, it is an effective reinforcing material.

Furthermore, when an appropriate amount of hydraulic setting material such as ordinary Portland cement, white cement, blast furnace cement, blast furnace slag fine powder cement, gypsum, etc. is mixed in the kneaded product, the kneaded product is cast into a mold and desired. When making shaped articles, it becomes possible to remove them from the mold and subject them to autoclave processing. When the hydraulic hardening material is not mixed, even if the kneaded product is cast in the mold, it will not cure by itself, and the shape will collapse when removed from the mold.
For this reason, it will be subjected to autoclave treatment as it is placed in the mold, but if an appropriate amount of hydraulic hardening material is mixed, a molded product with shape retention can be obtained, so it is removed from the mold and subjected to autoclave treatment. be able to. The mixing amount of the hydraulic setting material is a mixture of fine powder zeolite and lime 1
It may be in the range of 0 to 30 parts by weight with respect to 00 parts by weight. If the amount is more than 30 parts by weight, the strength does not increase so much, but the bulk specific gravity increases, and the performance as a building material is hindered.

Thus, regardless of whether or not other substances such as granular zeolite, fibers, and hydraulic hardening material are mixed in the kneaded material, the amount of the finely divided zeolite is the amount of the zeolite (CaO) relative to lime (CaO). The molar ratio of SiO _{2 in} zeolite (CaO
It is advisable to adjust / SiO ₂ ) to be in the range of 0.7 to 0.9. Depending on the type of zeolite, in terms of parts by weight, 100 parts by weight of lime will give approximately 100 to 100 parts of finely divided zeolite.
The mixing ratio may be 300 parts by weight, preferably about 130 to 200 parts by weight. By mixing fine powdery zeolite and lime in this amount ratio, the hydrothermal reaction proceeds favorably and the strength becomes sufficient, and unreacted differential zeolite also remains in the product building material.

When using the finely powdered zeolite (further, in some cases, granular zeolite), it is preferable to use one that has been activated in advance, as long as it is calcined at a temperature of 500 ° C. or higher.

In kneading, when fibers are mixed, it is preferable to add the fibers moistened with water and knead. In this case, kneading is preferably performed using a rubber ball mixer that vibrates in three dimensions. The amount of water added is not particularly limited as long as a uniformly kneaded molded product can be obtained, but it is approximately 50 to 150 parts by weight per 100 parts by weight of the total amount of finely divided zeolite and lime. And it is sufficient.

The kneaded product thus obtained is formed into a desired shape, but most typically, it is formed into a panel shape as an interior material. In that case, press molding can be performed depending on the case. In particular, when fibers are mixed, compression molding or compression squeeze molding is performed. The pressing force at that time is 5 to 200 kg / c
The range is m ² .

When the surface of the molded product does not become porous due to the pressure molding and the granular zeolite is likely to be crushed, a soft resin sheet is placed on the bottom surface and / or the top surface of the mold and press molding is performed. do it. Suitable resin sheets are urethane, silicone, synthetic rubber, and other sheet materials. As a result, the specific surface area important for the humidity control function can be secured without crushing the zeolite particles and leaving the irregularities on the surface of the molded body.

As described above, according to the present invention, not only the water adsorption / desorption properties of zeolite but also the properties such as fire resistance, heat insulation, ion exchange action, and safety are utilized as they are.
A humidity control building material as a cured product having sufficient strength can be obtained.

That is, zeolite has a property of adsorbing moisture in the air and a property of easily desorbing the adsorbed moisture. Due to this moisture absorption / desorption property, when the relative humidity of the ambient air rises, it absorbs moisture, and when it decreases, it releases moisture. Therefore, by using the building material of the present invention, it is possible to suppress and stabilize fluctuations in the relative humidity in the room.

Further, even under the condition that the surface temperature of the material is below the dew point of air and dew condensation occurs, the high water absorption of the zeolite prevents water droplets from forming, thereby preventing dew condensation. That is, even under the condition that general concrete products generate dew condensation, the material of the present invention does not cause dew condensation in the same environment.

Further, the zeolite in the material of the present invention has an action of suppressing the alkaline environment by adsorbing moisture accompanied by the alkali content scattered in the air and by the ion exchange action of the zeolite. Therefore, even if the alkali is scattered from the concrete of the building, the alkali suppressing action works in the space where the material of the present invention is used.

The building material according to the present invention has a bulk specific gravity of 0.7 to
It is as small as 1.0 and has a bending strength of 10-60 kg / cm ² . Therefore, it is lightweight and easy to handle. It is also easy to process.

[0030]

【Example】

(1) Hydrothermal reaction test [Materials used] Lime: Hard-baked lime powder Zeolite: Zeolites from Sendai (Kurinobu / Tirolite) Zeolites from Futatsui (Mordenite) Fibers: Plant fibers (improved white hair / maasusa) Chemical fibers (rayon)・ 7d × 10mm) Cement: (Ordinary Portland cement)

[Blending] Various blends were carried out in which the zeolite was SiO ₂ and the lime was CaO, and the molar ratio of CaO / SiO ₂ was changed in the range of 0.5 to 1.1, and the (zeolite + lime) / water ratio was 8
Water was added to 0% and kneaded with a mixer. The zeolite used was pulverized into fine powder having a particle size of 30 μm or less. When the fibers were blended, the fibers were mixed in advance with water. When cement was added, it was changed in the range of 10 to 30% with respect to the weight of lime.

[Molding] 40 × 4 of various kneaded products having the above composition
It was placed in a mold with a shape of 0 x 160 mm and left for 1 day after it was cast. Those without cement were placed in an autoclave with the mold attached and cement was mixed. The mold was removed and placed in an autoclave.

[Autoclave Treatment] The temperature inside the autoclave was kept constant at a temperature in the range of 130 to 180 ° C., and the treatment was carried out for 5 hours in each case. After autoclaving, dry at 45 ° C for 7 days and then use JIS R 5201.
A strength test was performed according to (Physical test method for cement).

[Strength Test Result] FIG. 1 shows the relationship between the molar ratio and the compressive strength and bending strength when the autoclave temperature was 150 ° C. without fiber and cement compounding.
As shown in Fig. 1, the strength varies depending on the type of zeolite, but the strength is exhibited in the molar ratio range of 0.7 to 0.9, indicating that the hydrothermal reaction is proceeding well.

FIG. 2 shows the relationship between the amount of cement added and the compressive strength and bending strength at an autoclave temperature of 150 ° C. when the amount of cement added was changed while the molar ratio was kept constant at 0.7. From Fig. 2, it can be seen that the strength tends to increase as the amount of cement added increases, but many cracks were found on the surface of the test specimen during drying before the strength test.

FIG. 3 shows the relationship between the autoclave temperature, the compressive strength and the flexural strength when the molar ratio is 0.7 and 0.9 and the fiber and cement are not mixed. As can be seen in Fig. 3, the compressive strength has a molar ratio of 0.9 at 150 ℃ and a molar ratio of 0.7 at 160 ℃.
Shows the maximum, and the bending strength is 150 ° C for both 0.7 and 0.9 molar ratios.
Indicates the maximum.

The relationship between the autoclave temperature and the compressive strength and flexural strength depending on the type of zeolite and the presence or absence of cement is shown in FIG. It can be seen that good strength can be obtained by setting the autoclave temperature to 140 to 160 ° C. regardless of the type of material.

The molar ratio is 0.7 and the autoclave temperature is 150.
FIG. 5 shows the relationship between the compressive strength and the flexural strength depending on the type of fiber when the temperature is set to ° C. It can be seen that when fiber is mixed, the strength is higher than when it is not mixed, and plant fiber has a greater effect of improving bending strength.

The molar ratio is 0.7 and the autoclave temperature is 130.
FIG. 6 shows the relationship between the compressive strength and the bending strength when the compounding amount of the plant fiber was changed at ° C. It can be seen that the compressive strength does not increase even when the fiber addition amount exceeds 1%, but the bending strength increases as the addition amount increases.

(2) Humidity control test 40 parts by weight of finely divided zeolite having a particle size of less than 30 μm, 25 parts by weight of lime, granular zeolite 32 having a particle size of 0.25 to 3 mm
By adding water to 3 parts by weight of polypropylene fiber and kneading with a mixer and molding to have a thickness of 15 mm, the mold is charged into the autoclave and treated at 150 ° C for 5 hours, A building material having a thickness of 15 mm was produced.

The obtained building materials were kept at a dry-bulb temperature of 20 ° C. at a constant relative humidity of 24% for 24 hours and a relative humidity of 72% for 2 hours.
The sample was placed in an artificial weather room where 4 hours were repeated alternately and the weight change was measured over time. The results are shown in Fig. 7.

The upper part of FIG. 7 shows changes with time of temperature and humidity in the artificial weather room, and the lower part shows changes of weight of the building material at the same time. For comparison, the same applies to a building material panel (cement building material) in which approximately the same amount of zeolite is hydraulically hardened using ordinary Portland cement, gypsum board, and artificial wood, which is said to be a commercially available humidity control material. The result of measuring the weight change is also shown in the lower part of FIG. 7.

The results of FIG. 7 show that the building material of the present invention absorbs and desorbs moisture in accordance with the change in the environment humidity about 5 times that of artificial wood, and is superior to the cement building material in which zeolite is cemented. It can be seen that it has a humidity control function.

Therefore, in a building space constructed by using the building material of the present invention, an excellent environment adjusting function for stabilizing the temperature and humidity in the environment even if the environment changes due to changes in temperature and relative humidity in the space. You can see that it has.

[0045]

As described above, according to the present invention,
It is possible to provide a building material having an excellent humidity adjusting function for keeping the humidity of the space constant. Since this building material is hardened by the hydrothermal reaction between zeolite and lime, it is lightweight, easy to handle, and easy to process.

The building material of the present invention is capable of not only controlling the humidity in the room and the building space but also preventing dew condensation due to the high moisture absorptive and desorptive property of zeolite, and also having an alkali content suppressing effect, and further having fire resistance and resistance. It has excellent corrosiveness, strength, dimensional stability, and durability, making it a suitable material as a permanent interior material with a humidity control function. In particular, it is also extremely effective as a material for the space that needs to maintain a constant environment such as works of art.

[Brief description of drawings]

[Fig. 1] A diagram showing the relationship between the compression ratio and the flexural strength with the molar ratio (the ratio of CaO / SiO ₂ of lime and finely divided zeolite, the same applies below) when the fiber and cement are not compounded and the autoclave temperature is 150 ° C. Is.

FIG. 2 is a diagram showing the relationship between the amount of cement added and the compressive strength and bending strength at an autoclave temperature of 150 ° C. when the amount of cement added was changed while the molar ratio was kept constant at 0.7.

FIG. 3 is a diagram showing the relationship between autoclave temperature, compressive strength, and bending strength when the molar ratio is 0.7, 0.9 and fibers and cement are not compounded.

FIG. 4 is a diagram showing the relationship between autoclave temperature, compressive strength, and bending strength depending on the type of zeolite and the presence or absence of cement with a molar ratio of 0.7.

FIG. 5 is a diagram showing the relationship between the compression strength and bending strength depending on the type of fiber when the molar ratio is 0.7 and the autoclave temperature is 150 ° C.

Fig. 6 Autoclave temperature 130 ° C with molar ratio 0.7
FIG. 3 is a diagram showing the relationship between compressive strength and bending strength when the amount of vegetable fiber is changed.

FIG. 7: Relative humidity 24 at a constant dry-bulb temperature of 20 ° C.
It is a figure which shows the weight change at the time of installing the building material of this invention and the comparative building material in the artificial weather room which repeats 24 hours for% and 24 hours for 72% of relative humidity by turns.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location E04B 1/64 D // (C04B 28/18 14:04 Z 2102-4G 16:02) Z 2102 −4G (72) Inventor Hiroki Kazumi 2-1-1, Tobita-yari, Chofu-shi, Tokyo Kashima Construction Co., Ltd. Technical Research Institute (72) Inventor Akio Sagae 2-1-1-1, Tobita, Chofu-shi, Tokyo Kashima Construction Co., Ltd. In the Technical Research Institute (72) Inventor Noriyoshi Maruyama No. 19-1 Tobita Supply, Chofu City, Tokyo Kashima Construction Co., Ltd. (72) Inventor Yoshinobu Arai No. 19-1 Tobita Supply, Chofu City, Tokyo Kashima Construction Co., Ltd. Company Technical Research Center (72) Inventor Yoshie Hirai Kabushiki Construction Co., Ltd. Technical Research Center

Claims (5)

[Claims] 1. A kneaded material composed of finely powdered zeolite having a particle size of 30 μm or less, lime and water is molded into a desired shape, and the molded product is heated at 130 ° C. to 180 ° C. in an autoclave.
A method for producing a building material in which a zeolite and lime are hydrothermally reacted while being maintained at a temperature of ℃, and the zeolite content in the kneaded product is adjusted so that unreacted zeolite that is not consumed in the hydrothermal reaction remains in the product building material. A method of manufacturing a building material for humidity control, which is characterized by adjusting. 2. The blending amount of finely divided zeolite is lime (Ca
Molar ratio of zeolite (SiO _{2 in} zeolite) to O)
The method for producing a building material for humidity control according to claim 1, wherein (CaO / SiO ₂ ) is adjusted to be in the range of 0.7 to 0.9. 3. The method for producing a building material for humidity control according to claim 1, wherein the kneaded mixture contains 30 parts by weight or less of a hydraulic hardening material with respect to 100 parts by weight of lime and finely divided zeolite. . 4. The method for producing a building material for humidity control according to claim 1, wherein the kneaded product contains 5 parts by weight or less of fibers with respect to 100 parts by weight of lime and finely divided zeolite. 5. The kneaded product contains 75 parts by weight or less of granular zeolite (particle size: 0.1 to 10 mm) based on 100 parts by weight of lime and finely divided zeolite.
Alternatively, the method for producing the building material for humidity control according to item 4.