JP3322870B2 - Concrete waterproofing agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Industrial applications]

The present invention relates to a waterproofing agent for concrete joints having good waterproofing performance. More specifically, the present invention relates to a waterproofing agent that can be sprayed on a joint surface of concrete in advance to prevent water leakage from a joint portion generated after curing.

[0002]

[Prior art]

Concrete is usually unhardened within 24 hours after casting, and if moisture such as rainwater enters during this time, the hardening becomes insufficient or the concrete is washed away. For this reason, after the casting, it must be covered with a sheet or the like to prevent rainwater or the like from entering. However, depending on the place to be cast, even if it is covered with a sheet or the like, it is not possible to prevent infiltration of rainwater or the like.

[0003]

[Problems to be solved by the invention]

There is a strong demand for a waterproofing agent for uncured concrete that is inexpensive and requires no labor for construction and that can be constructed even in the rain.

[Means for Solving the Problems]

The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, a dispersion of a water-insoluble powder in an aqueous solution in which a surfactant and a hydrophilic sizing agent are dissolved has been used to transfer uncured concrete. The present inventors have found that the infiltration of rainwater or the like into concrete can be stopped very simply by simply applying it to the part, thereby completing the present invention.

That is, the present invention relates to (1) (i) a surfactant (ii) aqueous polyvinyl acetate emulsion, sodium polyacrylate, aqueous polyacrylate, aqueous urethane resin, polyvinyl alcohol, sodium carboxymethylcellulose, and carboxyethylcellulose. At least one hydrophilic paste selected from the group consisting of sodium, sodium alginate and an aqueous synthetic rubber emulsion; (iii) a water-insoluble powdery substance; and (iv) water. (2) The ratio of the components constituting the waterproofing agent is 0.1 to 20% by weight of a surfactant, 0.1 to 20% by weight of a hydrophilic paste, 0.1 to 50% by weight of a water-insoluble powder, and 10 to 99.7% by weight of water. ).

[0005] The surfactant used in the present invention may be of any kind, and may be anionic, cationic, nonionic, amphoteric, etc. Specifically, fatty acid alkali metal salts, phosphoric acid Esters, polyquineethylene glycol,
Examples thereof include tetraalkylammonium salts, sodium alkyl ether sulfates, sodium alpha olefin sulfonates, fatty acid alkanolamides, and the like, or a mixture of two or more. Particularly preferred from an environmental standpoint are fatty acid alkali metal salts.

The surfactant is generally used in an amount of 0.1 to 20% by weight, preferably 2 to 10% by weight.
It is used in a weight percent loading. The surfactant improves the dispersibility of the water-insoluble powder in water, improves the compatibility with the concrete, and facilitates the entry of the water-insoluble powder into the burrow on the surface of the concrete joint. Therefore, when the amount of the surfactant is less than 0.1% by weight, the water-insoluble powdery substance disperses in water poorly, and the adaptability to the surface of the concrete joint is rapidly reduced, so that sufficient waterproof performance is not exhibited.

The hydrophilic sizing agent may be any of a natural sizing agent, a synthetic polymer sizing agent and the like, but a synthetic polymer sizing agent which does not easily rot is preferable. The sizing agent serves as a binder for the water-insoluble powdery substance, and has a function of preventing the water-insoluble powdery substance from flowing into the burrow on the concrete surface and then flowing away. The paste may be used alone or as a mixture of two or more. Specifically, polyvinyl acetate aqueous emulsion, sodium polyacrylate, aqueous polyacrylate, aqueous urethane resin,
Examples include polyvinyl alcohol, sodium carboxymethylcellulose, sodium carboxyethylcellulose, sodium alginate, and aqueous synthetic rubber emulsions.

The amount of the hydrophilic paste is 0.1 to 20% by weight, preferably 1 to 10% by weight. If the amount is less than 0.1% by weight, the water-insoluble powder has insufficient viscosity, so that the water-insoluble powder has poor dispersibility in water and tends to settle. Does not penetrate sufficiently and waterproof performance is not exhibited.

The water-insoluble powdery substance may be any of an organic substance powder and an inorganic substance powder, and is preferably one which is widely and uniformly distributed with a particle size of about 0.1 μm to 1 mm. The specific gravity of the particles is close to that of water 1.
About 0 or a little heavier is better, and those that float in water and disperse evenly are better. Specifically, synthetic resin powder, natural resin powder, clay, wood powder sufficiently impregnated with water, crosslinked superabsorbent resin, vermiculite, perlite, calcium carbonate, zeolite, silica powder, bentonite, silicic acid Magnesium and the like.

The water-insoluble powder may be used alone or in combination of two or more. Preferably, a combination having a wide particle size distribution is preferable. The compounding amount of the water-insoluble powder is 0.1 to 50% by weight, preferably 1.0 to 10% by weight. The amount of water is 10-99.7% by weight, but it is adjusted depending on the amount of rainfall. That is, when the amount of rainfall is large, the amount of water is preferably small, and where the amount of rainfall is small, it is preferable to increase the amount of water. In addition, since the viscosity significantly changes depending on the type and the degree of other components, it is preferable to adjust the amount of water to a viscosity that can be easily applied to the surface of the concrete joint.

[0011] As a method of using the waterproofing agent for a concrete joint portion of the present invention, the concrete may be applied after being applied to the surface of the concrete joint portion in advance. At this time, even if the applied waterproofing agent is dried and then joined, there is no change in waterproofing performance. Further, the waterproofing agent having a smaller amount of water may be applied during rainfall.

[0012]

【Example】

 Hereinafter, the present invention will be described in more detail by way of examples.

Example 1 A concrete waterproofing agent having the following composition was previously applied to a square concrete of 1 m on a side, and then a concrete having a thickness of 10 cm and a height of 40 cm was spliced to form a water tank having an inner size of 80 cm × 80 cm × 40 cm for one week. Thereafter, it was considered that the curing was sufficient, and the tank was filled with water, but there was no water leakage from the joint. In a water tank manufactured under the same conditions, in which the waterproofing agent was not applied to the joint portion, water leakage from the joint portion was observed 3 hours after filling with water. 1) Surfactant: Commercial powdered soap 50 g (trade name "Miyoshi Kona Soap" manufactured by Miyoshi Oil & Fat Co., Ltd.) Commercial synthetic detergent 10 g (trade name "Luna Mild" manufactured by Kao Corporation) 2) Hydrophilic paste: sodium polyacrylate 20g (trade name "Panakayak A" manufactured by Nippon Kayaku Co., Ltd.), commercially available transparent water-based acrylic paint 50g (trade name "water-based varnish" manufactured by Asahipen Co., Ltd.) and 30 g of commercial vinyl acetate emulsion resin (trade name "Cemedine White 605 for woodworking" 3) Water-insoluble powder: Wood flour (50-400 mesh) 15g Viscosity 50g (trade name "NK300" manufactured by Kunimine Industries) Bentonite 10g (tradename "Kunipia" manufactured by Kunimine Industries) 4) Water : 4800 g 1) to 4) were mixed and stirred to prevent sediment. In addition, the concrete tank which applied this aqueous solution to the joint part did not leak at all from the joint part two months after filling.

Example 2 The concrete tank to which the waterproofing agent was not applied beforehand, which was produced in Example 1, leaked due to water filling. After draining the water, the waterproofing agent having the composition of Example 1 was uniformly applied to the entire inner surface of the tank. And left for one day. Thereafter, the tank was filled with water, but even after one month, there was no leakage from the joint.

[0015]

【The invention's effect】

As described above, the waterproofing agent for concrete joints of the present invention is inexpensive, easy to apply, and regardless of whether the concrete is hardened or unhardened, a reliable waterproofing effect can be obtained even when applied in the rain. The outdoor concrete works are not hindered by rain, and the economic benefits are great.

Claims (2)

(57) [Claims] (1) Surfactant (ii) Aqueous polyvinyl acetate emulsion, sodium polyacrylate, aqueous polyacrylate, aqueous urethane resin, polyvinyl alcohol, sodium carboxymethylcellulose, sodium carboxyethylcellulose, sodium alginate and synthesis One or more hydrophilic pastes selected from the group consisting of rubber aqueous emulsions. (Iii) Water-insoluble powdery substances (iv) Water; 2. A patent wherein the proportion of components constituting the waterproofing agent is 0.1 to 20% by weight of a surfactant, 0.1 to 20% by weight of a hydrophilic paste, 0.1 to 50% by weight of a water-insoluble powder, and 10 to 99.7% by weight of water. The waterproofing agent for a joint according to claim 1.