JP2812200B2 - Waterproofing method for wet surface - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is useful as a waterproof material for structures such as water tanks, underground pits, walls, and roofs having a wet surface, and can be widely used in the field of civil engineering. is there.

[0002]

2. Description of the Related Art Concrete water tanks for water supply and sewerage are caused by cracks in concrete.
Frequent leaks can occur. As a countermeasure for this, usually, a treatment of applying a waterproof material to the inner surface of the tank is often taken. The waterproofing method for a substrate having a wet surface typified by such a water storage tank requires that the coating film of the undercoat material and the waterproofing material to be used is excellent in cracking the substrate and has excellent followability. Since it is always in contact with water, it is necessary to have excellent water resistance and to firmly adhere to the substrate even on a wet surface. Here, the ground cracking followability is
When the undercoat cracks due to hardening shrinkage of concrete or the like after the application of the undercoating material and the waterproofing material, it refers to the ability of the coating film to flexibly follow the elongation of the resulting coating film without breaking. In the water storage tank waterproofing method, furthermore, it is required that this property follow the film flexibly without being cured even under low temperature conditions in winter, and therefore, a high flexibility is required for the film. Conventionally, as a waterproofing method performed under such conditions, a method using an acrylic resin, an epoxy resin, a urethane resin, or an ethylene vinyl acetate-based resin has been generally used.

[0003]

However, in the conventional waterproofing method, it is difficult for the waterproofing material used to obtain a sufficient adhesive force to the wet surface substrate, so that the substrate must be sufficiently dried. In most cases, when the base was not sufficiently dried, blistering and peeling of the coating film occurred. In a waterproofing method using an epoxy resin-based waterproofing material, the waterproofing material is often an organic solvent-based material, and when this waterproofing material is used in a waterproofing method for a wet surface, the base material is wet. Since the underground having a surface or the inside of a tank is often a place with a considerably high degree of sealing, the odor is harmful to the worker, which is not preferable for the safety and health of the worker. The waterproofing method using epoxy resin has insufficient flexibility of the coating film and cannot follow cracks generated in the underlying concrete, causing not only water leakage, but also poor water resistance adhesion, Blistering, peeling or peeling was likely to occur. On the other hand, a construction method using an ethylene-vinyl acetate resin-based waterproofing material is used as an aqueous emulsion, and is generally used by mixing with a cement-based filler. The waterproofing material used in this method is a water-based waterproofing material, does not have the above-mentioned problems in the safety and health of workers, and is a water-based material. Although the adhesiveness is relatively excellent, there is a problem in water resistance due to the properties of the ethylene-vinyl acetate-based resin, and swelling, peeling and the like due to swelling and softening of the coating film have occurred. The present inventors, other than these construction methods, studied a construction method using a waterproof material in which an acrylic resin emulsion and various cement-based inorganic fillers are combined, and the composition is water-based, and its coating film Is water resistant,
It has been found that the adhesiveness to a base under a wet condition and the crack followability are superior to those of the above-mentioned waterproofing material composition. However, the performance has not been sufficient for use in a water tank having a wet surface. The present inventors are a construction method using a water-based undercoat material and a waterproof material, and the coating film is excellent in water resistance, cracking ability of the base, adhesion to the base under wet conditions such as underground and tanks. They worked diligently to find a waterproofing method.

[0004]

Means for Solving the Problems The object of the present invention is to provide an undercoating material for a polymer cement mortar containing an epoxy resin on the surface of a building to be waterproofed. The inventors have found that the problem can be solved by applying a waterproof material made of an inorganic water-curable substance such as an acrylic resin emulsion having a glass transition point of −20 ° C. or less and cement, and completed the present invention. That is, the first invention of the present invention is to apply the following composition (1) as a primer material on the surface of a building and then apply the following composition (2) as a waterproof material on the surface of the coating film. (1) containing 1 to 50% by weight of epoxy resin and 5 to 99% by weight of cement, based on the total solid content, and having a total amount of 40% by weight % Or more. (2) at least one monomer selected from alkyl (meth) acrylates having an alkyl group having 4 to 10 carbon atoms,
(Meth) acrylic acid and glycidyl (meth) acrylate are essential constituent monomers, and the glass transition point is -20 ° C.
A composition comprising an emulsion in which the following polymer is emulsified and dispersed in water with a surfactant, and an inorganic hydraulic substance. According to a second invention, the emulsion in the composition (2) is one or more monomers 3 selected from an alkyl (meth) acrylate having an alkyl group having 4 to 10 carbon atoms.
0 to 98% by weight, 0.1 to 3% by weight of (meth) acrylic acid
And glycidyl (meth) acrylate 0.1 to 5% by weight
Is an essential constituent monomer, and a polymer whose total amount of these essential constituent monomers is 30% by weight or more based on all constituent monomers and whose glass transition point is -20 ° C or less is a cation. The present invention relates to the waterproofing method for a wet surface according to the first invention, which is emulsified and dispersed in water with a water-soluble or nonionic surfactant. In this specification, acrylate and methacrylate are called (meth) acrylate, and acrylic acid and methacrylic acid are called (meth) acrylic acid.

[0005] 1. Undercoat Material The undercoat material used in the present invention is a composition (1) composed of an epoxy resin and cement, and is one kind of so-called polymer cement mortar.

1-1. Various resins can be used as the epoxy resin, for example, an epoxy resin obtained by reacting bisphenol A or its alkylene oxide adduct with epichlorohydrin, and hydrogenating bisphenol A or its alkylene oxide adduct with epichlorohydrin. The obtained epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin and the like can be mentioned. Here, examples of the alkylene oxide include ethylene oxide and propylene oxide. Glycidyl-type epoxy resins described in “Chemistry of Basic Synthetic Resins (New Edition)” (by Tadahiro Miwa, published by Gihodo), pp. 372-379, ibid., No. 38
Non-glycidyl type epoxy resins described on page 8 to page 391 are exemplified. A glycidyl type epoxy resin is preferred, and a liquid glycidyl type epoxy resin is particularly preferred.
These epoxy resins are commercially available, and include, for example, Epicoat 828 manufactured by Yuka Shell Epoxy Co., Ltd. The epoxy resin is preferably mixed with the cement in the form of an emulsion. As a surfactant for dispersing the epoxy resin in water, cationic surfactants may reduce the stability of the emulsion,
It is preferable to use an anionic or nonionic surfactant. Examples of the nonionic surfactant include polyethylene glycol type surfactants, and examples of the anionic surfactant include alkali metal salts of these sulfates or phosphates. Examples of the polyethylene glycol type surfactant include those obtained by adding ethylene oxide to a compound having active hydrogen such as a higher alcohol, a polyhydric alcohol, a fat or oil, a higher fatty acid, an alkylphenol, or an amine. Preferred surfactants are alkylphenols or oils and fats, especially ethylene oxide adducts of castor oil. The surfactants can be used alone or in combination of two or more. The amount of the surfactant used is usually 1 to 15 with respect to the resin solid content in the emulsion.
% By weight. The amount of epoxy resin in the primer should be from 1 to 50% by weight, based on the total solids in the primer. Outside this range, the ability to follow the base crack and the adhesion to the wet surface are reduced.

1-2. Cement Cement is compounded for the purpose of improving the toughness, water resistance, adhesion to wet surfaces, and dry film formability of the coating film. As the cement, a cement used in ordinary polymer cement can be used, and examples thereof include ordinary portland cement, alumina cement, and mixed portland cement such as blast furnace cement, silica cement, and fly ash cement. Two or more cements can be used in combination. The proportion of these cements in the undercoat material is 5 to 9 based on the total solids in the undercoat material.
It needs to be 9% by weight, preferably 5 to 90% by weight. If the amount is less than 5% by weight, the toughness of the coating film is reduced, and if it is more than 99% by weight, the water-resistant adhesiveness with the waterproof material is reduced. The total amount of the epoxy resin and the cement must be 40% by weight or more, preferably 50% by weight or more, based on the total solid content in the undercoat material.
If this value is less than 40% by weight, the undercoating material is difficult to dry and the adhesive strength is reduced.

1-3. Other Compounds Mono or Polyamidoamine Compound The undercoating material used in the present invention may optionally contain a mono or polyamidoamine compound in order to improve the film strength of the polymer cement mortar. Mono- or polyamidoamine compounds are mono- or polyamidoamine compounds having two or more active hydrogen atoms in the molecule that react with the epoxy resin. Usually, an acid component such as a polymerized fatty acid and / or a fatty acid is reacted with a polyamine in an amine excess. It is obtained by manufacturing. Examples of the polymerized fatty acid include unsaturated fatty acids having 18 carbon atoms such as oleic acid and linoleic acid, drying oil fatty acids, semi-dry oil fatty acids, and those obtained by dimolecular polymerization of lower monoalcohol esters of these fatty acids. . As fatty acids, for example, stearic acid, saturated fatty acids such as 2-ethylhexane, unsaturated fatty acids such as oleic acid, linoleic acid and linolenic acid, soybean oil fatty acids, natural oils such as tall oil fatty acids and cottonseed oil fatty acids are treated. Examples of the obtained fatty acid include a hydroxyl group-containing fatty acid of castor oil fatty acid or diphenolic acid, and a fatty acid obtained by treating a natural oil or fat containing a fatty acid having 12 to 24 carbon atoms. Examples of the polyamine include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, xylylenediamine, and metaphenylenediamine. Their content is preferably 0.5 to 70% by weight, more preferably 1 to 30% by weight, based on the epoxy resin in the undercoat material.

Higher fatty acids or salts thereof In the undercoating material of the present invention, higher fatty acids or salts thereof may be added, if necessary, in order to assist the penetration of the epoxy resin emulsion into the base. Specific examples of higher fatty acids include saturated or unsaturated fatty acids having 10 to 30 carbon atoms, such as lauric acid, oleic acid and stearyl acid. Examples of the salts of higher fatty acids include alkali metal salts such as sodium salts and potassium salts of these higher fatty acids, ammonium salts, and salts of amines such as lower amines and alkanolamines. The content of these is 0.0
Preferably it is 1 to 20% by weight.

Auxiliary agents In the undercoat agent of the present invention, auxiliary agents such as aggregates and waterproofing agents can be used, if necessary. Aggregates include river sand, sea sand, silica sand, calcium carbonate, talc, bentonite,
Examples include iron oxide, fly ash, alumina blast furnace water, and pigments. These can be blended in the composition at a ratio of 300% by weight or less. Sodium silicate, potassium silicate, SBR, NBR, EVA,
Non-reactive resin emulsion such as chloroprene rubber, C
Water-soluble resins such as MC and polyvinyl alcohol are exemplified. These can be blended in the waterproof material at a ratio of 30% by weight or less.

2. Waterproof material 2-1. Emulsion O Alkyl (meth) acrylate having an alkyl group having 4 to 10 carbon atoms Alkyl (meth) acrylate having an alkyl group having 4 to 10 carbon atoms, which is an essential constituent monomer of the polymer used in the waterproofing material of the present invention. Is n-butyl (meth) acrylate, iso-butyl (meth) acrylate,
sec-butyl (meth) acrylate, n-amyl (meth) acrylate, iso-amyl (meth) acrylate,
n-hexyl (meth) acrylate, n-heptyl (meth) acrylate, oxoheptyl (meth) acrylate,
n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate,
Oxononyl (meth) acrylate, n-decyl (meth)
Acrylate, oxodecyl (meth) acrylate and the like. (Meth) acrylates having an alkyl group having less than 4 carbon atoms are not preferred in terms of alkali resistance, while those having more than 10 carbon atoms are not preferred because of reduced cold resistance. The proportion of the above monomers in all monomers is
It is preferably from 30 to 98% by weight, more preferably from 40 to 90% by weight. If the proportion is less than 30% by weight, the film may have poor cracking ability, water resistance and alkali resistance. On the other hand, if it exceeds 98% by weight, a sufficient strength of the coating may not be obtained. There is.

○ (Meth) acrylic acid (Meth) acrylic acid used in the present invention acts as a cross-linking component with glycidyl (meth) acrylate, which is another essential constituent monomer component in the polymer. When a hard material is mixed, a polyvalent ion such as calcium in the inorganic hydraulic material and a carboxyl group form an internal crosslink to impart toughness to the coating film, and further, as a dispersant for imparting kneading stability. Also works. The proportion of these monomers in all the monomers is preferably 0.1 to 3% by weight. If this proportion is less than 0.1% by weight, the adhesive strength may be reduced, while if it exceeds 3% by weight, the water resistance and alkali resistance of the coating film may be reduced.

Glycidyl (meth) acrylate Glycidyl (meth) acrylate used in the present invention functions as a crosslinking component and imparts toughness to the coating film. Glycidyl (meth) acrylate is preferably contained in a proportion of 0.1 to 5% by weight in all monomers, more preferably in a range of 0.1 to 3% by weight from the viewpoint of polymerization operation. New When the amount of glycidyl (meth) acrylate is less than 0.1% by weight, the adhesive strength may be reduced. On the other hand, when the amount exceeds 5% by weight, the toughness of the coating film becomes too large or coagulation occurs in the polymerization operation. Things may easily occur.

Other monomers In the present invention, in addition to the above essential monomers, a monomer having an unsaturated ethylene bond copolymerizable therewith can be used if necessary. Include styrene, acrylonitrile, vinyl acetate and the like. These can be used in a proportion of less than 70% by weight based on the total monomers. Further, (meth) acrylates having an alkyl group having 3 or less carbon atoms, such as methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and iso-propyl (meth) acrylate, are also obtained. It can be used in a range that does not adversely affect the physical properties of the film, specifically, at a ratio of 0.1 to 28% by weight based on all monomers.

Glass transition point The polymer used in the present invention is a polymer having a glass transition point (hereinafter referred to as Tg point) of -20 ° C. or lower among the polymers obtained by polymerizing the above monomers. Those having a Tg point exceeding -20 ° C are not preferred because they are inferior in cracking of the underlayer and deteriorate in adhesion, and in many cases, have poor water resistance. The Tg point of the polymer used in the present invention is a temperature at which various properties of the amorphous polymer suddenly change. Below this temperature, a temperature at which the molecular segment motion of the amorphous portion of the polymer is frozen. The Tg point of the polymer in the present invention is determined by measuring the thermal expansion at various temperatures, plotting the specific volume for each temperature, and determining the temperature at the point where the curve is bent on the obtained curve. Measured. Since the value of the Tg point of the polymer composed of each single monomer is known,
The approximate value of the Tg point of the copolymer can also be determined by the following formula.

[0016]

(Equation 1)

CA; weight fraction of component A CB; weight fraction of component B TgA; Tg point of component A homopolymer (absolute temperature) TgB; Tg point of component B homopolymer (absolute temperature) where CA + CB = 1.

As a main polymer having a Tg point of -20 ° C. or lower (the Tg point in parentheses), polyethyl acrylate (−
22 ° C.), poly-n-butyl acrylate (−54
C), poly-2-ethylhexyl acrylate (-85
C.), and the polymer composed of monomers copolymerizable therewith and having a Tg point of −20 ° C. or lower includes polymethyl acrylate (8 ° C.), polystyrene (87 ° C.), and polyvinyl acetate (30 ° C.). ), Polymethacrylic acid (130 ° C)
Etc. (For the Tg point of polymers other than these,
(See the Chemical Handbook issued by Maruzen Co., Ltd.) The calculation of the Tg point of the copolymer is as follows. The Tg point of a copolymer of 70 parts by weight of butyl acrylate and 30 parts by weight of styrene is calculated from the equation (1). It will be -23 ° C.

Emulsion The emulsion used in the present invention can be easily obtained by polymerizing the above monomer in water, preferably in the presence of the following cationic or nonionic surfactant by a conventional method. Is the solid concentration of the resulting emulsion,
It is performed so as to be 30 to 70% by weight. The pH value of the emulsion is preferably 7 to 10 from the viewpoint of stability. The pH value of the emulsion is adjusted using ammonia, a water-soluble amine, sodium hydroxide, potassium hydroxide or the like.
It is preferable to adjust the value. However, an emulsion having good stability even in a weakly acidic or acidic region can be sufficiently used as it is for the purpose of the present invention. The emulsion used in the present invention may contain an antifoaming agent as another component. As the defoaming agent, generally used defoaming agents such as octyl alcohol, caprylic alcohol, auryl alcohol and cyclohexanol can be used. The compounding ratio of the antifoaming agent is preferably 0.1 to 5% by weight based on the solid content of the polymer.

Surfactant As the surfactant used for producing the emulsion used in the present invention, various surfactants can be used.
It is a cationic surfactant. Anionic surfactants may reduce the water resistance of the coating and may not be preferred for applications of the present invention that are constantly in contact with water. As the cationic surfactant that can be used in the present invention, various surfactants can be used, and specifically, trimethyloctadecyl ammonium chloride, trimethyl dodecyl ammonium chloride, trimethyl hexadecyl ammonium chloride, alkyldimethylbenzyl ammonium chloride, distearyl Quaternary ammonium salts such as dimethylammonium chloride and trimethylstearylammonium chloride, dimethyloctylamine, dimethyldecylamine, dimethyllaurylamine, dimethylmyristylamine, dimethylpalmitylamine, dimethylstearylamine, dimethyloleylamine, trioctylamine, N-methyl Tertiary amines such as morpholine, dimethylbenzylamine and polyoxyethylene alkylamine And the like. As the nonionic surfactant that can be used in the present invention, any nonionic surfactant can be used as long as it is generally used in an acrylic emulsion. Specific examples include polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyl phenol ether and polyoxyethylene alkyl or alkyl phenol ether such as polyoxyethylene nonyl phenol ether, and sorbitan monostearate. Sorbitan monolaurate, sorbitan distearate, sorbitan monooleate and sorbitan fatty acid esters such as sorbitan trioleate, polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, polyethylene glycol fatty acid esters, and glycerin monofatty acid Esters and the like. Among these surfactants, in particular, the polymerization stability and the mechanical and chemical stability are improved,
It is preferable to use a polyethylene oxide-based nonionic surfactant having an HLB value of 15 or more. The amount of the surfactant may vary depending on the properties required for the emulsion, but in order to improve the stability of the emulsion, the amount of the surfactant is preferably large, and the drying property and the coating In order to improve the water resistance of the composition, it is preferable that the amount is small. A preferable range of the amount is 1 to 10% by weight based on the polymer solid content of the emulsion, and the amount may be determined according to the purpose.

2-2. Inorganic hydraulic substance The inorganic hydraulic substance used in the present invention can be used in the above-mentioned emulsion to strengthen the coating film of the obtained composition, and to provide the coating film with water resistance, adhesion to a wet surface, and dry film formation. Performance can be improved. Examples of the inorganic hydraulic substance include various cements, anhydrous and hemihydrate gypsum, quicklime and zinc white. Among these, it is preferable to use cement, for example, ordinary Portland cement, alumina cement, early-strength cement, fly ash cement, blast furnace cement, white cement, colloid cement and moderately heated Portland cement, among others, furthermore, Portland cement or alumina cement, which is particularly easily available and can sufficiently exert the effects of the present invention, is preferable. These mineral hydraulic substances are
For 100 parts by weight of the solid content of the emulsion, 10
It is preferable to mix it in an amount of up to 300 parts by weight. If the amount is less than 10 parts by weight, the toughness of the coating film is not sufficient, and the adhesion to a wet surface may be inferior. 300
When the amount exceeds the weight part, the flexibility of the coating film is not sufficient,
Underground cracking may not be sufficient. Two or more inorganic hydraulic substances can be used in combination.

2-3. Other Ingredients The waterproofing material used in the present invention may contain a general-purpose filler. When compounding filler,
In some cases, effects such as improvement in coating workability, imparting toughness to the coating film, and reduction in coating tackiness are observed. As a specific example of the filler, general-purpose materials such as silica sand, talc, calcium carbonate, kaolin, gypsum, and diatomaceous earth can be used. The amount of the filler is preferably 20 to 600 parts by weight with respect to the inorganic hydraulic substance in the composition. When the amount is less than 20 parts by weight, the effect of compounding the filler is not particularly observed. When the amount is more than 600 parts by weight, cracking of the coating film is inferior, the viscosity is high, and the viscosity becomes high, and the coating workability may be reduced. is there.

3. Construction method Next, the waterproofing method of the present invention will be described. In the waterproofing method of the present invention, the undercoating material is applied to the surface of a building, and the waterproofing material is applied to the surface of the coating film. The method of applying the undercoating material and the waterproofing material may be performed by a usual method, for example, applying the undercoating material with a trowel, a brush or a roller, spraying with a machine such as a ricin gun, a spray gun, or waterproofing. There is a method of applying the material with a brush or a roller, or spraying the material with a machine such as a ricin gun or a spray gun. The viscosity of the waterproof material differs depending on the construction method, but is 300 cps or more (B
Type viscometer, 12 rotations, rotor No. (4, 20 ° C) is preferable because of excellent workability, and more preferably 1000 to 50,000 cps. 300c viscosity
When it is smaller than ps, it is difficult to apply a thick coating at a time, and when the viscosity is high, there is an advantage that the coating can be applied thickly, but there may be a difficulty in the construction. The coating amount of the waterproof material is preferably applied so that the film thickness after film formation is 300 μm or more, and more preferably 500 to 3000 μm.
m. If the film thickness is less than 300 μm, the base cracking ability may be reduced and cause water leakage. If the film thickness is too thick, the base cracking ability may be improved and cracks and cracks may not easily occur. Although there is an advantage, there is a case where the amount of the water-proofing material only increases and the corresponding effect cannot be obtained, and the inside of the coating film may be hardly dried.

○ Coating Material A coating material can be applied to the waterproof material of the present invention for the purpose of improving aesthetic appearance. Acrylic resin, acrylic urethane resin, acrylic silicone resin,
Fluororesins and epoxy resins are exemplified.

[0025]

The present invention will be specifically described below with reference to examples and comparative examples. In the following, “parts” means “parts by weight”, and “%” means “% by weight”. Example 1 (1) Production of Undercoating Material To 60 parts of a bisphenol-type epoxy resin having an epoxy equivalent of about 190, 5 parts of a nonionic surfactant nonylphenol 40 mol adduct of ethylenoxide, were melted and mixed at about 60 ° C. The mixture was stirred with a homomixer, and 35 parts of water was gradually added thereto to cause phase inversion, thereby obtaining 100 parts of an epoxy resin emulsion (epoxy resin content: 60%). The obtained epoxy resin emulsion and the following components were put into a mixing tank and stirred for about 5 minutes to obtain a polymer cement mortar (ratio to solid content of undercoating material: epoxy resin 12.8% by weight, cement 85% by weight). . This is called a primer material P-1. Epoxy resin emulsion: 100 parts Portland cement: 400 parts Water: 200 parts Monoamide polyamine (tetraethylenepe: 40 parts Manufactured from tertamine and cottonseed oil fatty acid, amine value about 380, solid content 15%) Sodium laurate: 4 Department

(2) Production of waterproofing material In a stainless steel reactor equipped with a stirrer having an inner volume of 20 liters, put 103.5 parts of ion-exchanged water and raise the internal temperature to 80 ° C.
After heating to 2-ethylhexyl acrylate 72
A mixture of 1 part, 1 part of methyl acrylate, 25 parts of styrene, 1 part of glycidyl methacrylate, 1 part of acrylic acid, 0.5 part of azobisaminopropane hydrochloride, and 3 parts of polyoxyethylene nonylphenyl ether (HLB 18.5) , Continuously dropped under stirring, while 2,2 was used as a polymerization catalyst.
One part of 2'-azobis-2-aminodipropane was continuously added dropwise with stirring to carry out a polymerization reaction. After 6 hours, the polymerization reaction was completed, and an emulsion having a solid concentration of 50% was obtained. The Tg point of the emulsion was -54C. This is called acrylic emulsion E-1. Mix 100 parts of acrylic emulsion E-1 and 50 parts of alumina cement,
I got a waterproof material. This is called waterproof material C-1.

(3) Preparation of Specimen A concrete plate (3
(0 × 30 × 5 cm), a slate plate (30 × 30 × 0.5 cm) as a test piece for a base crack followability test, and a mortar plate having a diameter of 15φ × 4 cm as a test piece for a pressurized water permeability test. The undercoat material prepared above was uniformly applied to each plate with a trowel, dried and then sprayed with 2.0 kg / m ² of a waterproof material on the coating film using an air spray gun.
0 ° C., 60% R.C. H. It was left for 7 days under the conditions to obtain a test specimen for evaluation. In the adhesion test on a wet substrate, a concrete plate was submerged for one week, then, as shown in FIG. 1, one third was put on the water surface and left for 4 hours.

(4) Wet Surface Substrate Adhesion Test The prepared specimens were evaluated for adhesion by peeling by hand (peeling test). The adhesive strength was measured with a Kenken-type adhesive strength tester, and the location of the failure was recorded. The coating film obtained by the waterproofing method of Example 1 had good adhesion as a result of the peeling test, and had an adhesion of 12 k in the Kenken type adhesion test.
gf / cm ² , the peeled portion was also a breakage of the waterproof material base material, and the adhesive strength on the wet surface substrate was good.

(5) Substrate cracking followability test The prepared specimen was divided into eight equal parts (150 × 75 × 5 mm),
Make a cut on the slate surface where no coating is applied,
It was processed into a test piece for a base crack followability test shown in FIG. The specimen was subjected to a tensile test in the direction of the arrow in FIG. 2 at a tensile speed of 5 mm / min, and the width of a crack following the occurrence of a pinhole or break in the coating film was measured. The coating film obtained by the waterproofing method of Example 1 had excellent crack followability of 4 mm.

(6) Pressure Permeability Test A test was conducted on the prepared specimen in accordance with JIS A1404.
The coating film of Example 1 had an extremely high water permeability of 0.005 g to 0.23 g at a water pressure of 1 to 5 kgf / cm ² .

Examples 2 to 4 As the undercoat material, the undercoat material P- having the composition shown in Table 2 which is different from the undercoat material P-1 only in the proportion of the epoxy resin and the cement.
2, P-3 and P-4 were used. An acrylic emulsion was produced in the same manner as in Example 1 except that a monomer having the composition shown in Table 1 below and a surfactant were used. This is called acrylic emulsion E-2. A waterproof material was produced in the same manner as in Example 1 except that the emulsion and the alumina cement were used. This is called waterproof material C-2. Waterproofing was performed using these undercoat materials and waterproof materials. Table 2 shows the results. It can be seen that within the range of the present invention, excellent performance is exhibited even when the weight ratio of cement of the undercoat material is changed.

[0032]

[Table 1]

[0033]

[Table 2] 1) A: waterproof material base material destruction 2) Value at 1 kgf / cm ² water pressure

Examples 5 to 7 Epoxy resin polymer cement mortar (trade name "Aron Epomol") manufactured by Toagosei Chemical Industry Co., Ltd. was used as a base coat material. This is referred to as a primer material P-5. Three acrylic emulsions E-3 and E were prepared in the same manner as in Example 1 except that a monomer having the composition shown in Table 3 below and a surfactant were used.
-4 and E-5 were produced. A waterproofing material having the composition shown in Table 4 was produced in the same manner as in Example 1 except that 100 parts of each emulsion, 30 parts of alumina cement and 30 parts of No. 8 silica were used. Waterproofing was performed using these undercoat materials and waterproof materials. Table 5 shows the results.

[0035]

[Table 3]

[0036]

[Table 4]

[0037]

[Table 5] 1) A: waterproof material base material destruction 2) Value at 1 kgf / cm ² water pressure

Comparative Examples 1 to 3 Undercoat materials P-6 and P- in Table 6 differing only in the proportion of epoxy resin and cement in undercoat material P-1
7 and P-8 were used. As the waterproof material, the waterproof material C-1 used in Example 1 was used. Waterproofing was performed using these undercoat materials and waterproof materials. Table 6 shows the results.

[0039]

[Table 6] 1) B: Undercoat material / underground interface destruction 2) Value at 1 kgf / cm ² water pressure

Comparative Examples 4 and 5 The undercoat material P-5 was used as the undercoat material. Two acrylic emulsions E-6 and E-7 were prepared in the same manner as in Example 1 except that a monomer having the composition shown in Table 7 below and a surfactant were used.
Was manufactured. Waterproofing materials C-6 and C-7 were produced in the same manner as in Example 1 except that the emulsion having the composition shown in Table 8 and alumina cement were used. Waterproofing was performed using these undercoat materials and waterproof materials. Table 9 shows the results.

[0041]

[Table 7]

[0042]

[Table 8]

[0043]

[Table 9] 1) A: waterproof material base material destruction 2) Value at 1 kgf / cm ² water pressure

Comparative Example 6 A test piece was prepared by applying only the undercoat material P-1. As a result, the adhesive strength with the substrate was 18 kgf / cm ² , the substrate crack following ability was 0.1 mm, and the water pressure in the pressure permeability test was 1 mm.
At 〜5 kg / cm ² , the water permeability was 15 g to 35 g.

Comparative Example 7 A test piece coated with only the waterproofing material C-1 was used. As a result, the adhesive strength with the substrate is 1.5 kgf / cm ² ,
Peeling from the interface between the waterproofing material and the substrate, and a significant delay in curing were observed. Substrate crack followability is 6mm (with span)
The water permeability at a water pressure of 1 to 5 kg / cm ² in the pressurized water permeability test is
The weight was 0.005 to 0.25 g.

[0046]

According to the waterproofing method of the present invention, even if the waterproof substrate is a wet surface, the obtained coating film has excellent adhesion to the substrate, excellent ability to follow the cracks, and excellent water-shielding properties. A high waterproof layer can be formed, and the undercoat material and the waterproof material to be used are water-based, so that the worker can safely perform the construction work.

[Brief description of the drawings]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view showing a concrete plate used in a wet surface substrate adhesion test, which is immersed in water after being immersed for one week.

FIGS. 2A and 2B are diagrams showing test pieces used in a base crack following test in Examples and Comparative Examples, wherein FIG. 2A is a top view and FIG. 2B is a side view.

[Explanation of symbols]

 1 Concrete board 2 Water 3 Undercoat and waterproof coating

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-98687 (JP, A) JP-A-60-74000 (JP, A) JP-B 3-79494 (JP, B2) (58) Field (Int.Cl. ⁶ , DB name) E02D 31/02 E02D 29/00 E03B 11/00

Claims (2)

(57) [Claims] 1. A wet surface, comprising applying the following composition (1) as an undercoat material on the surface of a building, and then applying the following composition (2) as a waterproof material on the surface of the coating film. For waterproofing method. (1) A composition containing 1 to 50% by weight of an epoxy resin and 5 to 99% by weight of a cement based on the total solid content, and having a total amount of 40% by weight or more. (2) at least one monomer selected from alkyl (meth) acrylates having an alkyl group having 4 to 10 carbon atoms,
(Meth) acrylic acid and glycidyl (meth) acrylate are essential constituent monomers, and the glass transition point is -20 ° C.
A composition comprising an emulsion in which the following polymer is emulsified and dispersed in water with a surfactant, and an inorganic hydraulic substance. 2. An emulsion in the composition (2), wherein 30 to 98% by weight of one or more monomers selected from alkyl (meth) acrylates having an alkyl group having 4 to 10 carbon atoms, (meth) acrylic acid 0.1 to 3% by weight and 0.1 to 5% by weight of glycidyl (meth) acrylate are essential constituent monomers, and the total amount of these essential constituent monomers is 30% by weight based on all constituent monomers. The wet surface waterproofing method according to claim 1, wherein the polymer having a glass transition point of -20C or lower is emulsified and dispersed in water with a cationic or nonionic surfactant.