JPH0412357B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to improvements in fireproof insulation walls in safes, fireproof storages, fireproof panels, and the like.

[Prior art] This type of fire-resistant insulation wall is usually made of a heat-resistant water-based curing agent such as cement or gypsum as a base material, and a fire-resistant insulation material such as asbestos is mixed into the base material, or aluminum powder is mixed into the base material. Foaming agents like these were mixed in to form countless microbubbles in the wall, thereby reducing its thermal conductivity. In this case, the insulation performance is proportional to the amount of the insulation material or foaming agent mixed in, but there is a limit to the amount that can be mixed in because mixing a large amount of these materials will reduce the strength of the wall. There was a problem in that it had to be made thicker.

Therefore, the applicant focused on the fact that water that exists as free water within the wall without chemically bonding with cement etc. absorbs a large amount of latent heat when it evaporates.
In the previously filed Japanese Patent Publication No. 54-32246, it was proposed that water be absorbed in advance by a water-absorbing material such as silica gel, which releases little water at room temperature, and mixed into the wall. In other words, water-absorbing materials release almost no water at room temperature and retain a large amount of water as free water within the wall for a long period of time, but when heated in a fire, etc., the water is gradually released and evaporates. By making use of the heat absorption effect of the material, the heat insulating effect is maintained for a long period of time.As a result, it has been possible to obtain a significantly superior heat insulating effect while maintaining the same thickness as the conventional one.

[Problem that the invention seeks to solve]

However, it has been found that the method disclosed in the above-mentioned publication also suffers from some drawbacks. In other words, the heat insulation effect depends on the amount of free water contained within the wall, or more precisely, the ratio of the amount of base material such as cement to the amount of water contained in the water absorbing material. Since its water content is not very high and if a large amount is mixed into the wall, the strength of the wall will be reduced, so the ratio cannot be increased above a certain value. In addition, even if the amount of water released by the water absorbing material is small, it does not mean that it is completely sealed, so the water will gradually be released into the atmosphere, and it cannot be denied that the insulation performance will deteriorate over time. Nakatsuta.

As a prior art to solve this inconvenience,
Publication No. 48-7743 describes an agglomerate in which bicarbonate powder of an alkali metal is covered with a film such as paraffin that dissolves when the temperature rises, and an agglomerate that absorbs heat from the bicarbonate due to the rise in temperature. Two types of powders of metal salts of acids having reactive crystal water and agglomerates covered with a film such as paraffin which is impermeable at room temperature but dissolves when the temperature rises are mixed as appropriate as a heat insulating material. is suggesting.

However, according to this configuration, in order for the two types of compounds to cause a predetermined endothermic reaction and exhibit the effectiveness of the fireproof wall, the two types of agglomerates must be present at a predetermined ratio and the degree of distribution of both agglomerates must be It is necessary to mix them so that they are not biased. Furthermore, the film (capsule) of each agglomerate, which is water-impermeable and dissolves when the temperature rises, generally has low compression resistance, so during the mixing process of two types of agglomerates or the weight of the wall itself, , there is a large risk that the film (capsule) of each agglomerate will be torn (destroyed), and once the film (capsule) is torn, the chemical reaction will be accelerated as mentioned above, and the insulation performance will become high over time. There was a problem that it could not be maintained.

The present invention improves the insulation effect by utilizing the latent heat of vaporization of free water contained in the wall.The present invention dramatically improves the insulation performance by increasing the water content without reducing the strength of the wall. The purpose is to completely prevent the deterioration of thermal insulation performance over time.

[Means for solving problems]

That is, in the present invention, a water-absorbing material impregnated with water in advance is formed into a double layer consisting of a first coating that is impermeable to water at room temperature and permeable or soluble at high temperatures, and a second coating that is water permeable and pressure resistant. The granules are coated with granules and mixed in an appropriate amount into the wall.

In this case, there is a case where the second covering body covers the outer periphery of the first covering body, and a mode where the first covering body covers the outer periphery of the second covering body.

[Action of the invention]

When the wall is configured in this way, the water contained in the water-absorbing material is sealed in the first coating, which is impermeable at room temperature and permeable or soluble at high temperatures, and is separated from the base material such as cement. Since it is non-contact, water can be contained in the wall regardless of the amount of the base material, and the ratio of free water to the base material can be greatly increased. By being made of a material with a high hardness (pressure resistance), the covering functions as an aggregate, and even if a large amount is mixed in, the strength of the wall will not be reduced.

When the temperature of the wall increases due to a fire, etc., the entire granule is heated and the moisture inside evaporates, and the first coating also melts or becomes water permeable due to the temperature rise, so it is water permeable and water permeable. The moisture is released into the wall through the pressure-resistant second covering, and the temperature of the wall is prevented from rising due to the endothermic action of the latent heat of vaporization.

In addition, the first coating containing the water-absorbing material is non-water permeable at room temperature, so no moisture in the particles is released at room temperature, and the second coating is water permeable, but has a high pressure resistance Since the powder of the present invention is mixed with other base materials or by its own weight when used as a wall, the first coating will not be crushed or destroyed, and the moisture in the granules will not be crushed or destroyed. Since it is not emitted under normal conditions, there is no problem that the insulation performance deteriorates over time.

〔Example〕

Next, referring to an embodiment of the present invention, reference numeral 1 indicates a base material 2 in which a water-based curing agent having fire resistance such as fire-resistant cement is kneaded with water, and a foaming agent such as aluminum powder as shown in FIG. A fireproof heat insulating wall is shown in which appropriate amounts of granules 3 made by encapsulating a pre-hydrated water-absorbing material 4 in a double layer with a first coating 5 and a second coating 6 are mixed and cured. .

In the embodiment, the base material 2 is foamed concrete in which countless microbubbles (not shown) are formed in the concrete by the action of a foaming agent.

In this case, as the base material 2, gypsum or the like may be used instead of cement, and a fire-resistant insulating material such as asbestos, ceramic fiber, lightweight aggregate, etc. may be mixed instead of or together with the foaming agent. You can do it like this.

The water absorbing material 4 in the granules 3 is intended to retain moisture, and its materials include, for example, viscosity increasing agents such as starch or acrylic acid polymers (super absorbent polymers), porous resins, etc. There are many types of materials such as water-absorbing resins, cotton, whitebait, volcanic rock, and pumice. However, from the purpose of the present invention, it is preferable that the amount of water contained in the granules 3 is as large as possible. Are suitable.

Further, the first covering 5 can seal the moisture enclosed in the water-absorbing material 4 at room temperature, and can release the moisture to the outside when heated to a temperature above a certain level.

For this reason, it is required that it be water-impermeable and have a certain hardness at room temperature, and that it be water-permeable or have the property of dissolving at a certain high temperature. Examples of materials that meet these conditions include synthetic resins such as ethylene-vinyl acetate copolymer (EVA), water glass, and low-melting metal alloys.

Among these synthetic resin materials, in addition to EVA, polyvinyl acetate, vinyl acetate copolymer,
Vinyl acetate acrylate, dibutyl acetate maleate, vinyl acetate-beoba, vinyl acetate-ethylene, acrylic acetate copolymer, acrylic acetate-X methyl tacrylate,
Acrylic acid ester-styrene, vinylidene chloride copolymer, vinyl chloride copolymer ethylene, epoxy resin, synthetic rubber latex, etc. are also used. Note that the first covering 5 may also have a function as an aggregate that further increases the strength of the base material 2.

The second covering 6 has water permeability and pressure resistance, which functions as an aggregate that increases the strength of the base material 2. Examples include hydraulic hardening materials such as concrete and cement mortar. .

In the embodiment shown in FIG. 1, the outer periphery of the water-absorbing material 4 covered with the first covering 5 is further covered with the second covering 6; It is also possible to form a two-layer structure in which the first covering body 5 is coated on the outer side of the first covering body 4.

In this way, one of the two inner and outer coverings 5 and 6 is formed of a material that has hardness like concrete but is also water permeable, and the other layer is formed of a non-water permeable, slightly heat-resistant material. When formed in two layers as shown in FIG. , 6 are relaxed, and the range of material selection becomes wider.

Note that the particle size of the granules 3 is desirably about 3 to 15 mm in view of ease of granulation and role as aggregate.

When the wall 1 configured in this manner is heated from the outside and reaches a certain temperature, the first covering 5 melts due to the heat or ruptures due to internal pressure, and the second covering 6 which is water permeable is heated. The internal moisture is released into the wall 1 through the layer, and when it evaporates, it takes away a large amount of heat of vaporization and prevents the temperature of the wall 1 from rising. In this case, heat is transmitted from the outside of the wall 1 toward the inside, so moisture is released from the parts of the grains 3 closer to the outside, and the release of moisture is continuous and over a long period of time. It will be.
Therefore, by increasing or decreasing the mixing ratio of the granules 3 to the base material 2 such as cement constituting the wall 1, a desired fire-resistant and heat-insulating performance can be obtained.

In addition, when constructing a wall of a safe, a fireproof storage, etc., the entire wall with the thickness to may be formed with the fireproof heat insulating wall 1 according to the present invention, as shown in FIG.
Thickness t on one side of the wall of total thickness t as shown in the figure
Only one portion may be formed of the fireproof heat insulating wall 1 of the present invention. Alternatively, it may be stacked with other heat insulating material layers to form a sandwich-like structure, or may be combined as appropriate depending on the function required of the wall.

The graph in FIG. 6 shows a comparison of the fireproof performance of the fireproof heat insulating wall 1 according to the present invention as described above and a conventional product. This is done by heating the outer surface of the wall according to the heating curve based on the JISA1304 regulations for fire resistance testing as shown in Figure 5, and measuring the elapsed time on the horizontal axis and the inner surface temperature of the wall on the vertical axis. This shows the relationship between Among these, the curves shown by solid lines and broken lines indicate the product according to the present invention, and the curve shown by solid lines is the curve shown in FIG. The fire resistance performance is shown when the inner t1 = 15 mm of the foamed concrete 7 is formed with the fireproof insulation wall 1 according to the present invention in which the granules 3 are mixed in the foamed concrete.

Also, the curve shown with a broken line indicates the wall thickness as shown in Figure 4.
This is a fire resistance curve when the entire wall of to=40 mm is formed of the fire resistant heat insulating wall according to the present invention. In addition, both are 15
The measured values are plotted every minute.

On the other hand, the dashed-dotted line and the dashed-double line both indicate the fire resistance curve for a conventional product whose entire wall is made of foamed concrete, and the dashed-dotted line indicates the wall thickness of 60 mm.
In the case of , the two-dot chain line is the fire resistance performance curve for the case of 40 mm. As is clear from this figure, it has been demonstrated that by configuring all or part of a 40 mm thick wall according to the present invention, it is possible to obtain fireproof insulation performance equivalent to or superior to that of a conventional 60 mm wall. .

Regarding the method for producing the granules 3, the granules 3 are granulated by a rolling granulation method, a spray granulation method, or the like. Among these methods, the rolling granulation method involves rolling the granular water-absorbing material 4, which has been pre-hydrated, on an inclined surface while spraying special cement or EVA powder, etc., and sprinkling it over the entire surface.
A material that quickly solidifies to form the coating 5, and
In the spray granulation method, the process of spraying powdered material for the first coating 5 onto the surface of the granular water-absorbing material 4 that has been pre-hydrated is repeated several times to obtain a first coating with a substantially uniform thickness. 5 and then similarly form the second
It forms the covering body 6. When the first covering body is made of synthetic resin, it may be made into an emulsion state and then coated with the water absorbing material 4. In this case, it is effective to form the water-absorbing material 4 in advance using a granulator and then granulate it, since granulation becomes easy and granules 3 having a substantially uniform size can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, a water-absorbing material is impregnated with water, and the first covering is impervious to water at room temperature and permeable or soluble at high temperatures, and the second covering is water permeable and pressure resistant. Since it is coated with a double layer of 2 coatings, formed into granules, and mixed into the wall, a large amount of water can be retained as free water within the wall, and it can be used to prevent fires, etc. Because this is released into the wall continuously and over a long period of time,
The heat insulation effect due to the latent heat of vaporization of free water can be dramatically improved. Therefore, the fire resistance and heat insulation performance can be improved without changing the thickness of the wall. Since the first covering is water-impermeable at room temperature, no internal moisture is released over time, and its high heat insulating performance can be maintained forever.

Furthermore, the granules enclosing the water-absorbing material are coated with a second coating that is water-permeable and pressure-resistant, has a certain hardness, and functions as an aggregate that increases the strength of the wall. , during the mixing operation of the base material and the granules, the first
Even if the covering is damaged or a large amount is mixed into the wall, the strength of the wall will not be reduced. Therefore, the ratio of free water to the wall base material such as cement can be freely adjusted, and the fire resistance performance can be varied over a wide range without changing the wall thickness. In particular, it is convenient if applied to safes, fireproof storages, etc., since fireproofing performance can be improved without narrowing the storage space for items.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is an enlarged cross-sectional view of a grain, FIG. 2 is a partially enlarged cross-sectional view of a wall, FIG. 3 is a cross-sectional view showing the entire wall, and FIG. A sectional view of another example, FIG. 5 is a diagram showing a heating curve in a fire resistance test specified in JISA1304, and FIG. 6 is a diagram showing fire resistance performance of the product of the present invention and a conventional product. DESCRIPTION OF SYMBOLS 1... Fireproof insulation wall, 3... Particles, 4... Water absorbing material, 5... First covering body, 6... Second covering body, 7...
...foamed concrete.

Claims (1)

[Scope of Claims] 1. In forming a wall by mixing a fire-resistant water-based curing agent with a fire-resistant heat-insulating additive or a foaming agent, a water-absorbing material pre-impregnated with water is placed inside the wall at room temperature. The first is water-impermeable and high-temperature water-permeable or high-temperature soluble.
1. A fireproof and insulating wall comprising a suitable amount of granules coated with a double layer of a covering body and a second covering body having water permeability and pressure resistance. 2. The fireproof heat insulating wall according to claim 1, wherein the water absorbing material is a viscosity increasing agent. 3. The fireproof heat insulating wall according to claim 1 or 2, wherein the first covering is made of an ethylene/vinyl acetate copolymer. 4. The fireproof heat insulating wall according to claim 1, 2 or 3, wherein the second covering is made of cement mortar.