JP2001139931A - Paste for water stop - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pasty water stop having a swelling ability in water in spite of water solubility possessed thereby without using a mineral oil. SOLUTION: This paste for the water stop is characterized by comprising at least one or more kinds of sugar alcohols, saccharides or polyhydric alcohols and a natural or a synthetic clay mineral exhibiting water swellability. A paste for water stop comprising the natural or synthetic clay mineral exhibiting the water swellability in an amount of 10-400 pts.wt. based on 100 pts.wt. of a solution containing 30-100 wt.% of the sugar alcohols and/or saccharides is especially preferred.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof material used for waterproofing work, repair and the like. More specifically, the present invention relates to a water-stopping paste having a water-swellable clay mineral having excellent water-stopping property, self-sealing property, and stability over time as a main component, and further having excellent workability and plasticity.

[0002]

2. Description of the Related Art Conventionally, resin-based waterproofing materials such as vinyl chloride, rubber-based, and asphalt-based waterproofing materials have been used as waterproofing materials for buildings and underground structures. Also,
As inorganic water-blocking materials, cement-based and smectite-based mainly bentonite have been used. Depending on the place where the water stopping work is performed, the shape of the water stopping material is a sheet, a panel, a band, or a paste.

[0003]

The greatest performance of a water-stopping material, when incorporated into a structure, is to exhibit a long-term water-stopping performance stably. However, conventional organic water blocking materials
Since the affinity for concrete is low, a minute gap is easily generated between the waterproof material and the concrete, and there is a problem that water penetrates from the gap by a capillary phenomenon. In the case of swellable rubber, it has been pointed out that due to the swelling pressure of the rubber, the swelling rubber may act on concrete before hardening and may cause fine cracks. These organic water-stop materials deteriorate in several decades and cannot maintain the initial water-stop performance. On the other hand, cement-based water-blocking material, which is an inorganic water-blocking material, has no problem of deterioration, but does not have self-sealing property like organic water-blocking material. Can penetrate, and a stable water stopping effect cannot be expected.

[0004] Smectite-based water-blocking materials exhibit self-sealing properties by swelling without a problem of deterioration, and thus have a characteristic of exhibiting long-term stable water-blocking performance. BACKGROUND ART Conventionally, bentonite, which is a main clay mineral of smectite, which has been processed into a powdery or granular form, has been used as a waterproof material in the form of a sheet or panel. However, when performing waterproofing work, it is not possible to perform waterproofing work on narrow parts or complex shaped parts with sheets and panels, and organic waterproofing paste mainly composed of urethane, silicon, asphalt is used together However, this organic water-blocking paste does not guarantee a long-term water-blocking effect.

[0005] In addition, some gelling of bentonite has been proposed, but it has already been gelled.
Since it does not swell with water, it has low self-sealing properties, is easy to flow by rainwater after construction, and cannot fill gaps with new cracks, so that a stable water stopping effect cannot be expected. Therefore, it is desirable to form a paste while maintaining the swelling power against water. As a method for this, a paste using mineral oil has been proposed. However, in this type of paste, mineral oil leaks out of the paste and contaminates the construction part, and in some cases, it may flow out and pollute the environment. In addition, it seems to handle grease, has a strong smell, and is difficult to clean when attached to tools and hands, and handling is troublesome.

[0006]

Means for Solving the Problems In view of the above problems, as a result of diligent research, a clay mineral having a water swelling property is used as a main component,
The present invention has led to the invention of a paste-like water-stopping material having water swelling ability without using mineral oil and having water solubility. The waterstop paste of the present invention is characterized by containing at least one or more of a sugar alcohol, a sugar and a polyhydric alcohol, and a natural or synthetic clay mineral exhibiting water swellability. This paste for waterproofing is prepared using the sugar alcohol and / or sugar 30 to 30-
It is preferable to mix 10 to 400 parts by weight of a natural or synthetic clay mineral exhibiting water swellability with 100 parts by weight of a solution containing 100% by weight. Bentonite is particularly preferred as the water-swellable clay mineral.

In the water-stopping paste of the present invention, a solution containing a sugar alcohol, a sugar or a polyhydric alcohol has a low water activity value, and even when a natural or synthetic clay mineral showing water swelling property is dispersed therein, such a water is used. Swellable natural or synthetic clay minerals do not readily swell in solution. And
When this paste comes into contact with water after construction, the concentration of sugar alcohol, sugar or polyhydric alcohol decreases, and a natural or synthetic clay mineral exhibiting water swelling exhibits water swelling for the first time.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described. In the water-stopping paste of the present invention, at least the water-stopping material is composed of a clay mineral having a water swelling property and a solution for making it into a paste. The clay mineral used in the present invention needs to have a water-stopping effect, and needs to self-swell to form a fine colloid upon contact with water. Specifically, smectite clay minerals and swellable mica have the characteristics, but they may be natural products or synthetic ones. These clay minerals may be used alone, but may be used in combination as long as they do not affect the water stopping effect. Bentonite, one of the smectite-based clay minerals, is often used as a water-stopping material, and has a reputation for a stable water-stopping effect. Therefore, it is a desirable clay mineral to use.

There are two types of bentonite: sodium-type and calcium-type bentonite. Sodium-type bentonite has a larger swelling ratio than calcium-type bentonite. However, calcium-type bentonite has a property that the reaction to water is faster than sodium-type bentonite. In the bentonite used for the water-stopping paste in the present invention, activated calcium-type bentonite has excellent swelling amount and swelling speed, and is more desirable in view of the water stopping effect. Such activated calcium-type bentonite is, for example, based on 100 parts by weight of calcium-type bentonite.
It is obtained by adding 4 parts by weight of soda ash (sodium carbonate), adding water, kneading, drying and pulverizing.

As a solution for dispersing the clay mineral, a solution containing at least one kind of sugar alcohol, sugar or polyhydric alcohol is used. The components constituting this solution are substantially water except for at least one or more components of sugar alcohol, sugar or polyhydric alcohol. These solutions have a low water activity value, and do not easily swell in the solution even when a water-swellable clay mineral is dispersed therein. Examples of the sugars and sugar alcohols used include monosaccharides such as glucose, fructose, galactose and mannose; oligosaccharides such as sucrose; reducing disaccharides such as maltose; raffinose, gentianose; Sugars, isomerized sugars, sugar alcohols such as sorbitol and mannitol can be used. As the polyhydric alcohol, those having a low water activity value and not hindering the swelling of the clay mineral are preferred. Specific examples include glycerin, ethylene glycol, propylene glycol and the like, and propylene glycol is most preferred. These sugar alcohols, sugars or polyhydric alcohols
Each of them may be used alone, or two or more of sugar alcohols, sugars or polyhydric alcohols may be used as a mixture. Among them, a mixed solution of components selected from sugar alcohols is preferable, and a solution in which sorbitol and another sugar alcohol are mixed is particularly preferable.

The solution containing at least one of sugar alcohols, sugars and polyhydric alcohols has a water activity value of preferably 0.9 or less, more preferably 0.8 or less in consideration of the swelling property of the clay mineral. . Here, the water activity value means a value measured by a water activity measurement device manufactured by Nova Sina using a relative humidity measurement method.

The water-static paste of the present invention comprises, for example, 10 to 400 parts of a water-swellable natural or synthetic clay mineral per 100 parts by weight of a solution containing 30 to 100% by weight of the sugar alcohol and / or sugar. It is obtained by mixing parts by weight. In particular, the sugar alcohol and / or sugar is preferably 30 to 10
A paste obtained by mixing 50 to 200 parts by weight of a natural or synthetic clay mineral exhibiting water swellability with 100 parts by weight of a solution containing 0% by weight is preferable. Most preferably, a mixture obtained by mixing 60 to 120 parts by weight of a natural or synthetic clay mineral exhibiting water swelling with 100 parts by weight of a solution containing 70 to 80% by weight of the sugar alcohol and / or sugar is used. preferable. This paste has excellent performance as a paste, and is inexpensive and highly safe.

The concentration of the sugar alcohol and / or sugar in the solution mixed with the clay mineral is 30 to 100% by weight;
If the concentration is less than 30% by weight, there is a problem that the clay mineral swells in the solution. If the amount of the clay mineral added to the solution is less than 10% by weight, the paste is too soft, and if it exceeds 400% by weight, the paste becomes too hard, which may cause trouble in the paste application.

In the case of a polyhydric alcohol, by mixing it with a clay mineral under the same conditions as in the case of the above-mentioned sugar alcohol and / or sugar, performance equivalent to that of the sugar alcohol and / or sugar can be obtained. However, considering the performance of the paste and the safety of the paste during storage or construction, etc., the polyhydric alcohol is 15 to 50% by weight,
A paste obtained by mixing 50 to 200 parts by weight of a natural or synthetic clay mineral exhibiting water swelling with 100 parts by weight of a solution containing 15 to 85% by weight of a sugar alcohol and / or a sugar is preferable. Preferably 3 alcohols
0-50% by weight, sugar alcohol and / or sugar 40-
A paste obtained by mixing 60 to 120 parts by weight of a natural or synthetic clay mineral exhibiting water swelling with 100 parts by weight of a solution containing 50% by weight is desirable. At this time, when mixing a solution containing a sugar, a sugar alcohol or a polyhydric alcohol with a natural or synthetic clay mineral exhibiting water swellability, any mixer may be used, and a paste is easily prepared at room temperature. can do.

The water-stopping paste thus produced is
It has plasticity, can be changed in shape as needed, and can be applied to parts that require water stoppage. When this paste is brought into contact with water, the concentration of sugar, sugar alcohol or polyhydric alcohol is reduced, and the clay mineral exhibits water swelling properties for the first time and exhibits a water stopping effect. Especially when using sugar alcohol,
Due to the high osmotic pressure, water quickly moves into the paste and the clay mineral swells quickly. Since the water-stopping material of the present invention depends on the colloidalization of the clay mineral due to the water swelling property of the clay mineral, it does not have the problem of deterioration unlike the organic water-stopping material, and exhibits a self-sealing property. Shows stable water stopping performance for a period. In addition, bentonite is a natural mineral, so it is excellent in safety, and sugar and sugar alcohol are not toxic,
It is harmless to the user when handling the paste, and even if the components of the paste are eluted, the load on the environment is extremely low. In addition, handling is easy because the paste is water-soluble. Since the sugar and sugar alcohol solution are hard to freeze, the paste also has a characteristic of being plastic even at a constant temperature.

[0016]

EXAMPLES The present invention will be further described based on examples.
The present invention is not limited to these. In each of the examples and comparative examples, the water stoppage effect was compared by measuring the swelling amount and the water permeability. <Measurement of swelling amount> 100 ml of distilled water was put into a 100 ml graduated cylinder, 2 g of a sample was charged, and the volume after 24 hours was measured. The swelling volume per 1 g was defined as the swelling amount. <Measurement of Permeability>"Permeability" Soil Testing Method (3rd revised edition) Edited by the Editorial Committee, "Method and Explanation of Soil Testing" Published by Japan Society of Soil Engineering, Measured by constant water permeability test according to the method described did.

Example 1 Activated bentonite was added to 100 parts by weight of an aqueous solution containing 70% by weight of glucose.
0 parts by weight were mixed and kneaded to obtain a paste. This was designated as Sample 1. The paste showed good plasticity. Table 1 shows the swelling amount of the obtained sample 1. The hydraulic conductivity is
It was 4.2 × 10 ^-9 . The apparent specific gravity of this sample was 1.25 g / ml.

Example 2 Activated bentonite 1 was added to 100 parts by weight of an aqueous solution containing 70% by weight of sorbitol.
00 parts by weight were mixed and kneaded to obtain a paste. This was designated as Sample 2. The paste showed good plasticity. Table 1 shows the swelling amount of the obtained sample 2. Further, the hydraulic conductivity was 3.1 × 10 ⁻⁹ .

Example 3 100 parts by weight of activated bentonite was mixed with 100 parts by weight of a 100% by weight solution of glycerin and kneaded to obtain a paste. This was designated as Sample 3. The paste showed good plasticity. Table 1 shows the swelling amount of Sample 3 obtained. The permeability is 3.5 × 1
0 was ^-9.

(Example 4) Propylene glycol 100
Activated bentonite 1 per 100 parts by weight of the solution
00 parts by weight were mixed and kneaded to obtain a paste. This was designated as Sample 4. The paste showed good plasticity. Table 1 shows the swelling amount of the obtained sample 4. Further, the hydraulic conductivity was 2.5 × 10 ⁻⁹ .

Comparative Example 1 200 parts by weight of activated bentonite was mixed with 100 parts by weight of mineral oil and kneaded to obtain a paste. This was designated as Sample 5. The paste showed good plasticity. Table 1 shows the swelling amount of the obtained sample 5.

Comparative Example 2 For 100 parts by weight of distilled water,
50 parts by weight of activated bentonite were mixed and kneaded to obtain a paste. This was designated as Sample 6. The paste showed good plasticity. Table 1 shows the swelling amount of Sample 6 obtained.

[0023]

[Table 1]

From the swelling amounts shown in Table 1, Examples 1 to 4 were obtained.
It can be seen that the paste has a swelling amount that is nearly 5 times. Comparative Example 1 using mineral oil has a larger swelling amount than the example. However, based on the bentonite content, the swelling amounts of Examples 1 to 4 can be said to be equivalent to Comparative Example 1. In Comparative Example 2 using distilled water, almost no swelling was observed because bentonite had already swelled. Thus, the water-stop paste obtained according to the present invention does not use oil such as mineral oil, has good water swelling properties, shows good swelling properties, and has excellent properties of 1.0 × 10 ⁻⁸ or less. It shows water permeability and shows that it has excellent ability as a water-stopping material.

[0025]

The water-stopping paste obtained according to the present invention comprises:
Because it has plasticity, it can be used anywhere and is excellent in workability. In addition, since it is mainly composed of clay mineral, it does not deteriorate, has a self-sealing property by swelling, and can expect a stable water stopping effect over a long period of time. Since no oil such as mineral oil is used as the pasting agent, it is safe for the installer and has almost no impact on the environment. In addition, the work of pasting is easy, and the work at the construction site is also possible, which can greatly improve the conventional construction method of the waterproof material.

Claims (3)

[Claims] 1. A water-stopping paste comprising at least one kind of sugar alcohol, sugar or polyhydric alcohol, and a natural or synthetic clay mineral exhibiting water swellability. 2. The sugar alcohol and / or sugar 30-1.
The water stopping paste according to claim 1, wherein 10 to 400 parts by weight of a natural or synthetic clay mineral exhibiting water swelling is mixed with 100 parts by weight of a solution containing 00% by weight. 3. The water-swellable natural or synthetic clay mineral is bentonite.
Or the paste for waterproofing according to claim 2.