JPH05208879A - Concrete coat curing agent and concrete-curing method using the same - Google Patents

Abstract

PURPOSE:To improve the durability of the concrete layer by coating the surface with a concrete curing agent containing an emulsion of an epoxy resin modified with a polysulfide which is represented by a specific formula and a polyamine or polyamide. CONSTITUTION:A polysulfide-modified epoxy resin represented by the formula (R1 and R3 are an organic group bearing a bisphenol skeleton; R2 is a S- containing organic group), a nonionic surfactant and water are mixed under stirring to form an O/W emulsion. 100 pts.wt. of the emulsion are mixed with 2 to 200 pts.wt. of a polyamine or polyamide dispersible in water, an appropriate amount of water, when necessary, filters, reinforcing agents to prepare the objective concrete-curing agent. Then, cement, aggregate and water are mixed and poured into a prescribed plastic vessel, and the mortar surface newly formed is coated with the concrete-curing agent in a prescribed thickness, then cured to give the concrete of high durability.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a concrete film curing agent,
And a concrete curing method using the same, in particular, it is possible to suppress the amount of water vaporization in the initial stage of curing, the concrete strength development is fast, and a concrete film curing agent capable of constructing high-strength concrete having high durability, And a method for curing concrete using the same.

[0002]

2. Description of the Related Art Concrete is liable to form on the concrete surface when the water inside the concrete evaporates after the hydration reaction of cement progresses after the completion of driving and the concrete is sufficiently hardened. Cracking occurs and the strength of the concrete after hardening is reduced. In particular, the surface of concrete that has been driven in when the temperature is high or the humidity is low is apt to dry and crack when exposed to direct sunlight or wind. Therefore, it is necessary to quickly cure the concrete that has been driven in so that the exposed surface does not dry. in this case,
It is preferable to keep the exposed surface in a wet state for at least 24 hours after the driving so that the exposed surface is not dried, and perform curing for 7 days or more.

Further, in construction such as road pavement where it is difficult to cut off traffic for a long period of time, it is necessary to raise concrete to practical strength early so as to shorten the construction period. For this reason, cemented concrete with a low unit moisture content was applied to road and airport aprons to control the moisture content in the concrete to increase the initial load resistance and enable early service. Concrete pavement method has been developed.

Further, in recent years, in order to improve frost damage resistance and salt resistance of concrete and improve durability of concrete,
It has been found effective to reduce the water / cement ratio in concrete mixes. Concrete that is constructed in cold regions, seas and coasts that are susceptible to frost damage and salt damage needs a control amount of water, and the addition of excess water deteriorates the durability of concrete.

In a structure with a large exposed surface such as a concrete pavement, it is necessary to suppress the amount of water vaporization in the initial stage of curing. Especially, in a concrete with a small water / cement ratio, the curing reaction occurs when the moisture evaporates before complete curing. It is not possible to secure the required amount of water for high strength concrete and it is not possible to construct high strength concrete.

For this reason, when the temperature is high or the humidity is low, it is necessary to water the concrete surface immediately after the concrete is poured into the concrete to make the concrete surface wet. However, this sprinkling curing requires sprinkling water each time the surface of the concrete is dried, and the work is complicated. Further, sprinkling curing is difficult to perform in the case of concrete curing in a wide area such as an airfield or an expressway.

[0007] There is a method of using a synthetic resin type curing mat for the purpose of eliminating the complexity of work due to sprinkling curing.
According to this method, concrete is cured by covering the concrete surface with a curing mat when the surface of the concrete is no longer floating and hardening of the surface to some extent, and then water is sprayed from the top to retain the water.

However, even in this construction method, when the temperature is high or the humidity is low, it is necessary to sprinkle water as the concrete surface is dried. Further, troubles such as the curing mat being blown off may occur during strong winds. Furthermore, after the concrete is hardened, it is necessary to remove the curing mat, which is troublesome.

Therefore, a method of applying a film curing agent such as polyvinylidene chloride emulsion at the time when the surface begins to harden to a certain extent to prevent cracking of concrete is carried out. However, the existing film curing agent has a small effect of preventing water evaporation of concrete, and has only a temporary effect until the curing mat is installed. In addition, the current film curing agents such as polyvinylidene chloride emulsions cause pinholes due to the effect of calcium in the floating water on the concrete surface immediately after the concrete is poured into the concrete, that is, when the concrete surface is covered with water. There is a problem that it does not become a protective film. In addition, when applying when the surface of the concrete has hardened, it is necessary to sprinkle water on the surface of the concrete so as to saturate the surface of the concrete.

Therefore, an object of the present invention is to suppress the amount of water vaporized at the initial stage of hardening by hardening immediately after the concrete is poured and hardening even when the concrete surface is covered with water to form a curing film. The present invention is to provide a concrete film curing agent capable of producing a high-strength concrete having high durability and high strength development of concrete.

Another object of the present invention is to provide a concrete curing method capable of obtaining a high-strength concrete having a high concrete strength development and a high durability by suppressing the evaporation amount of water in the early stage of hardening of the concrete. Is to provide.

[0012]

Means for Solving the Problems In view of the above object, as a result of intensive studies, the present inventors have found that an emulsion of an epoxy resin having an epoxy group at the terminal and containing a bisphenol skeleton in the molecule and water can be dispersed. If a concrete film curing agent obtained by mixing with various polyamines or polyaminoamides is applied immediately after the concrete is poured, it will cure even when the concrete surface is covered with water to form a curing film. The inventors have found that it is possible to suppress the amount of evaporation of water, and as a result, a high-strength concrete having high durability can be obtained at an early stage, and conceived the present invention.

That is, the concrete film curing agent of the present invention comprises (A) an epoxy resin emulsion containing an epoxy resin having an epoxy group at the terminal and a bisphenol skeleton in the molecule, and (B) a water-dispersible polyamine or It is characterized by containing a polyaminoamide.

In particular, in the above concrete film curing agent, as the epoxy resin, the following general formula:

[Chemical 3] (However, R ₁ and R ₃ are organic groups containing a bisphenol skeleton, and R ₂ is an organic group containing a sulfur atom.) It is preferable to use a polysulfide-modified epoxy resin.

Further, the concrete curing method of the present invention comprises: (A) an epoxy resin emulsion containing an epoxy resin having an epoxy group at the terminal and a bisphenol skeleton in the molecule; and (B) a polyamine or a water-dispersible polyamine. It is characterized in that a concrete film curing agent containing polyaminoamide is applied to the surface of concrete after construction to form a concrete curing film and suppress the evaporation of water from the concrete in the initial stage of hardening.

Particularly, in the above-mentioned concrete curing method, the following general formula as an epoxy resin:

[Chemical 4] (However, R ₁ and R ₃ are organic groups containing a bisphenol skeleton, and R ₂ is an organic group containing a sulfur atom.) It is preferable to use a polysulfide-modified epoxy resin.

The present invention will be described in detail below. First, the concrete film curing agent of the present invention will be described. The concrete film curing agent of the present invention contains an emulsion of an epoxy resin having an epoxy group at the end and having a bisphenol skeleton in the molecule, and a polyamine or polyaminoamide dispersible in water.

Examples of the epoxy resin having an epoxy group at the terminal and containing a bisphenol skeleton in the molecule used in the present invention include bisphenol A type epoxy resin,
Examples thereof include bisphenol AD type epoxy resin, halogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin and halogenated bisphenol F type epoxy resin.

Further, a preferable example of the epoxy resin having an epoxy group at the terminal and containing a bisphenol skeleton in the molecule is a polysulfide-modified epoxy resin represented by the following general formula (1).

[Chemical 5]

(R ₁ and R ₃ in the above general formula (1) are organic groups containing a bisphenol skeleton, and R ₂ is a polysulfide skeleton.)

Examples of the organic groups R ₁ and R ₃ containing the bisphenol skeleton include bisphenol A type epoxy resin, bisphenol AD type epoxy resin, halogenated bisphenol A type epoxy resin, and bisphenol F.
Examples thereof include those having a molecular structure equivalent to those of the epoxy resin of the type, halogenated bisphenol F type epoxy resin and the like, or those having a similar molecular structure.

The polysulfide skeleton R ₂ in the general formula (1) is represented by the following general formula (2). (−R ₄ −S _m ) _n− (2)

In the above general formula (2), the average content m of S is in the range of 1 to 3, preferably 1.5 to 2.5.
Is. Furthermore, the range of the average content n of the polysulfide skeleton is 1 to 50, preferably 2 to 30. When the average content n of the polysulfide skeleton is less than 1, it becomes equivalent to that of a normal bisphenol type epoxy resin, and when n exceeds 50, the viscosity becomes high and it becomes difficult to use.

In the general formula (2), R ₄ is an organic group such as an alkylene group or an ether bond-containing alkylene group, which may have a substituent such as an OH group or COOH, and has a carbon number of Is 1 to 30. Examples of such R ₄ include the following.

-(CH ₂ ) _a -,-(CH ₂ OC
_{H 2) a -, - (} CH 2 CH (OH) CH 2) a -,
_{- (CH 2 CH (CH 3} )) a -, - (CH 2 CH 2
_{OCH 2 OCH 2 CH 2) a} - ( provided that, a represents 1 or more, preferably an integer of 1 to 6).

Specific examples of R ₂ include those mentioned above. Among them, those having —SS— (disulfide bond) are preferable, and those represented by the following chemical formula (3) are particularly preferable. _{- (CH 2 CH 2 OCH 2} OCH 2 CH 2 SS) n - ··· (3) ( where, n is an integer from 1 to 50, preferably 2 to 30
Is an integer. )

A commercially available product of such a polysulfide-modified epoxy resin is FL manufactured by Toray Thiokol Co., Ltd.
EP-10, FLEP-50, FLEP-60, FLE
P-80 etc. can be mentioned.

In the present invention, this polysulfide-modified epoxy resin and a general epoxy resin containing no sulfur atom (the above-mentioned bisphenol A type epoxy resin, bisphenol AD type epoxy resin, halogenated bisphenol A type epoxy resin) are used. Resin, bisphenol F-type epoxy resin, halogenated bisphenol F-type epoxy resin, etc.) can be blended and used. In this case, it is preferable that the total amount of the epoxy resin is 100% by weight and the proportion of the polysulfide-modified epoxy resin is 30% by weight or more. Particularly, it is preferable that the polysulfide-modified epoxy resin is 60% by weight or more and the general epoxy resin containing no sulfur atom is less than 40% by weight.

A surfactant is used to emulsify an epoxy resin having an epoxy group at the terminal as described above and containing a bisphenol skeleton in the molecule. In the present invention, a nonionic surfactant is particularly used. Is preferred.

The nonionic surfactant used in the present invention is, for example, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene dodecylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, There are sorbitan monolaurate, sorbitan monostearate, etc., and those having an HLB value in the range of 8 to 18 are preferable. These nonionic surfactants are
They may be used alone or in combination of two or more depending on the case.

In the present invention, as an emulsification method for obtaining an emulsion, a generally used emulsification method can be used, but it is preferable to use a phase inversion emulsification method. That is,
First, a small amount of water is added to an oil component (epoxy resin-containing organic solvent) to which a surfactant has been added and mixed to obtain a W / O type emulsion. Next, water is gradually added to invert the phase to finally obtain an O / W type emulsion.

The epoxy resin may be dissolved in an organic solvent. Examples of the organic solvent that can be used include toluene, xylene, ethyl acetate, butyl acetate, methylene chloride, chloroform and the like.

The apparatus used for mixing is preferably a shaft stirrer having a rotary blade, a homogenizer, a homomixer, a colloid mill and the like. The emulsification temperature is preferably in the range of 10 to 80 ° C. More preferably, it is in the range of 30 to 50 ° C.

The amount of the surfactant added is the epoxy resin 10
It is preferably 100 parts by weight or less, more preferably about 5 to 20 parts by weight, relative to 0 parts by weight.

In order to obtain an emulsion having excellent stability, it is effective to add a water-miscible organic solvent capable of dissolving the surfactant used. When such a water-miscible organic solvent is added, the surfactant can be efficiently dispersed in the oil component, so that the W / O (oil-in-water) type emulsion generated in the initial phase inversion emulsification can be easily generated. .. This W / O
The water dispersed in the type emulsion has the function of crushing the oil from the inside at the phase inversion stage, which is achieved by adding more water, so the particles of the O / W type emulsion obtained are very It becomes very small. As a result, it is considered that an emulsion having excellent stability can be obtained.

Examples of water-miscible organic solvents include monoalcohols such as methanol, ethanol, butanol,
Polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propylene diol, 1,4-butane diol, glycerin, acetone, dimethyl sulfoxide, N, N-dimethylformamide, tetrahydrofuran, dioxane, etc. Is. In the emulsification, these water-miscible organic solvents may be used alone or, in some cases, two or more kinds may be used in combination. When a water-miscible organic solvent is added, the amount of addition should be 1
The amount is preferably 100 parts by weight or less, more preferably 30 to 70 parts by weight, based on 00 parts by weight.

In the present invention, the epoxy resin emulsion obtained as described above is mixed with water-dispersible polyamines or polyaminoamides as a curing agent.

Examples of such polyamines include modified aliphatic polyamines (for example, "Adeka Hardener EHE-027" and "Adeka Hardener EH-22" manufactured by Asahi Denka Co., Ltd.).
0 "," ADEKA HARDNER EH-227 "," ADEKA HARDNER EH-230 "and" ADEKA HARDNER EH-261 "," Daitokural J-1666 "," Daitokural X-1777A "and "Daito Clar X-2392", Dainippon Ink and Chemicals Incorporated "Laccamide WH-036-S", Fuji Kasei Co., Ltd. "Fujicure # 5420", Mitsui Petrochemical Co., Ltd. "Epomic Q" -611 "," Epicure 3012 "manufactured by Yuka Shell Epoxy Co., Ltd.," Epicure XD-35 "
8 "," Epicure H-3 "and" Epicure H-5S "etc.)
, Modified alicyclic polyamine (for example, Daito Sangyo Co., Ltd. "Daitokural X-1321", Fuji Kasei Co., Ltd. "Fujicure FXD-822", etc.), modified polyamine (for example,
Daito Sangyo Co., Ltd. "Daitokural U-4075", "Daitokuraru I-1199", "Daitokuraru I-4036", "Daitokuraru X-973", "Daitokuraru X-1301S",
"Daitokuraru X-1942", "Daitokuraru X-1840"
And "Daitokural X-2733", "Fujicure # 5001" and "Fujicure E-1604" manufactured by Fuji Kasei Kogyo Co., Ltd., "React CA-101" and "React CA-102EM" manufactured by Sanyo Chemical Co., Ltd. "Epomate N-001", "Epomate QX-2", "Epomate B-00" manufactured by Yuka Shell Epoxy Co., Ltd.
2W "," Epicure 3255 "and" Epicure SE-11 "
And the like.

Commercial products of polyaminoamides include, for example, "Adeka Hardener" manufactured by Asahi Denka Kogyo Co., Ltd.
"EH-203", "ADEKA HARDNER EH-204", "ADEKA HARDNER EH-303", "ADEKA HARDNER EH-321", "ADEKA HARDNER EH-331" and "ADEKA HARDNER EH-36"
0 ”,“ Tomade # 238 ”and“ Tomade 225 # ND ”manufactured by Fuji Kasei Kogyo Co., Ltd., and the like.

In the present invention, the amount of polyamines or polyaminoamides used varies depending on the type of polyamines or polyaminoamides used. Usually, the amount is about 2 to 200 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the epoxy resin emulsion. By setting the amount of the polyamines or polyaminoamides used within the above range, the reaction between the epoxy resin emulsion and the polyamines or polyaminoamides becomes more complete, and a complete curing film is formed.

The concrete film curing agent of the present invention is obtained mainly by mixing an epoxy resin emulsion with water-dispersible polyamines or polyaminoamides. ,
Silica sand, wollastonite, clay, titanium oxide, white carbon, silica, talc, calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, bentonite, mica, kaolin, quartz powder, etc. A stopper or the like can be added.

The concrete curing method using the concrete film curing agent of the present invention is carried out by applying the concrete film curing agent as described above to the concrete surface after driving to form a curing film. Good. In such a concrete curing method, the concrete film curing agent composition used hardens to form a curing film even when the concrete surface is covered with water. The amount can be suppressed, and thus high-strength concrete with high durability can be obtained at an early stage. In the above-mentioned curing method, the application of the concrete film curing agent is not limited to immediately after driving, but may be performed after that (for example, when floating water decreases to some extent).

[0043]

As described above, the concrete film curing agent of the present invention comprises an epoxy resin emulsion (preferably polysulfide-modified epoxy resin emulsion) having epoxy groups at the ends and a bisphenol skeleton in the molecule, and a polyamine dispersible in water. Or polyaminoamides. The concrete film curing agent thus obtained has toughness and high water vapor barrier properties. In particular, the concrete film curing agent obtained by using the polysulfide-modified epoxy resin emulsion is excellent in chemical resistance, durability and adhesiveness in addition to being further improved in toughness and water vapor barrier property. Further, due to the effect of emulsification, the affinity for concrete immediately after driving is extremely good, and a uniform concrete curing film is formed.

Further, when concrete is cured using the concrete film curing agent of the present invention, the composition can be cured to form a curing film even when the concrete surface is covered with water. It is possible to suppress the amount of evaporation of water from the concrete at the initial stage of hardening, and thus it is possible to early obtain a high-strength concrete having high durability.

[0045]

The present invention will be described in more detail by the following examples. Synthesis Example 1 Synthesis of Polysulfide-Modified Epoxy Resin Emulsion 100 parts by weight of polysulfide-modified epoxy resin (“FLEP-10” manufactured by Toray Thiokol Co., Ltd.) and a nonionic surfactant (“Nugen EA” manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
-157 ": polyoxyethylene alkylaryl ether) 5 parts by weight and water 20 parts by weight are mixed, and the mixture is stirred and mixed with a homogenizer at 5000 rpm for about 3 minutes to obtain W / O.
A type emulsion was obtained. Continuing, the total amount of added water is 1
When water addition and stirring were repeated until the amount reached 100 parts by weight, phase inversion occurred and an O / W type polysulfide-modified epoxy resin emulsion was obtained. The appearance of the emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 2.0 to 3.0 μm.

Synthesis Example 2 Synthesis of Polysulfide-Modified Epoxy Resin Emulsion 100 parts by weight of polysulfide-modified epoxy resin ("FLEP-50" manufactured by Toray Thiokol Co., Ltd.) and a nonionic surfactant ("Daiichi Kogyo Seiyaku Co., Ltd." Neugen EA
-157 ") 5 parts by weight and 20 parts by weight of water are mixed and mixed by stirring with a homogenizer at 5000 rpm for about 3 minutes,
A W / O type emulsion was obtained. Subsequently, when water addition and stirring were repeated until the total amount of added water reached 100 parts by weight, phase inversion occurred and an O / W type polysulfide-modified epoxy resin emulsion was obtained. The appearance of the emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 2.0 to 3.0 μm.

Synthesis Example 3 Synthesis of Polysulfide-Modified Epoxy Resin Emulsion 100 parts by weight of polysulfide-modified epoxy resin ("FLEP-60" manufactured by Toray Thiokol Co., Ltd.) and a nonionic surfactant ("Daiichi Kogyo Seiyaku Co., Ltd." Neugen EA
-157 ″), 20 parts by weight of ethylene glycol, 10 parts by weight of ethylene, and 20 parts by weight of water were mixed and stirred with a homogenizer at 5000 rpm for about 3 minutes to obtain a W / O type emulsion. When water addition and stirring were repeated until the total amount of the above was 100 parts by weight, phase inversion occurred, and an O / W type polysulfide-modified epoxy resin emulsion was obtained. The average particle size of the epoxy resin particles in the emulsion was 2.0 to 3.0 μm.

Synthesis Example 4 Synthesis of Epoxy Resin Emulsion 100 parts by weight of a bisphenol type epoxy resin (“Epicoat 828” manufactured by Yuka Shell Epoxy Co., Ltd.) and a nonionic surfactant (“Neugen” manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.). E
A-157 ") 5 parts by weight and 20 parts by weight of water are mixed,
The mixture was stirred and mixed at 5000 rpm for about 3 minutes with a homogenizer to obtain a W / O type emulsion. Subsequently, when water addition and stirring were repeated until the total amount of water added reached 100 parts by weight, phase inversion occurred and an O / W type epoxy resin emulsion was obtained. The appearance of the emulsion immediately after emulsification was good, and the average particle size of the epoxy resin particles in the emulsion was 2.0 to 3.0 μm.

Measurement of Moisture Evaporation Inhibitory Effect (1) Example 1 100 parts by weight of the polysulfide-modified epoxy resin emulsion obtained in Synthesis Example 1 and a modified aliphatic polyamine (“Adeka Hardener EH-22” manufactured by Asahi Denka Co., Ltd.)
0 ″) 10 parts by weight was mixed to obtain a concrete film curing agent.

Next, a plastic container having a length of about 25 cm, a width of about 18 cm and a depth of about 7 cm was prepared, and 20 parts by weight of sand and 10 parts by weight of cement were placed in the plastic container.
6 parts by weight of water were mixed thoroughly and placed in a plastic container to a depth of 4 cm.

On the surface of the mortar thus obtained, the concrete film curing agent was applied so as to have a film thickness of 0.5 mm, and then cured at room temperature for 1, 3 and 7 days, respectively, and after each curing period. The rate of change in weight of the mortar was measured to evaluate the effect of suppressing water evaporation. The results are shown in Table 1 along with the formulation, proportions and film thickness of the curing film.

Example 2 100 parts by weight of the polysulfide-modified epoxy resin emulsion obtained in Synthesis Example 2 and a modified aliphatic polyamine (“Adeka Hardener EH-22” manufactured by Asahi Denka Co., Ltd.)
0 ″) 10 parts by weight was mixed to obtain a concrete film curing agent.

This concrete film curing agent was applied onto the surface of a mortar similar to that used in Example 1 so that the film thickness would be 0.5 mm, followed by curing at room temperature for 1, 3 and 7 days, respectively, and after each curing period. The rate of change in weight of the mortar was measured to evaluate the effect of suppressing water evaporation. The results are shown in Table 1 along with the formulation, proportions and film thickness of the curing film.

Example 3 100 parts by weight of the polysulfide-modified epoxy resin emulsion obtained in Synthesis Example 3 and a modified aliphatic polyamine (“Adeka Hardener EH-22” manufactured by Asahi Denka Co., Ltd.)
0 ") 12 parts by weight was mixed to obtain a concrete film curing agent.

This concrete film curing agent was applied to the surface of a mortar similar to that used in Example 1 so that the film thickness would be 0.5 mm, followed by curing at room temperature for 1, 3 and 7 days, respectively, and after each curing period. The rate of change in weight of the mortar was measured to evaluate the effect of suppressing water evaporation. The results are shown in Table 1 along with the formulation, proportions and film thickness of the curing film.

Example 4 The film curing agent of Example 1 was applied to the surface of a mortar similar to that of Example 1 so that the film thickness would be 0.3 mm, and the film was cured at room temperature for 1, 3 and 7 days, respectively. The rate of change in weight of the mortar after each curing period was measured to evaluate the effect of suppressing water evaporation. The results are shown in Table 1 along with the formulation, proportions and film thickness of the curing film.

Example 5 100 parts by weight of the polysulfide-modified epoxy resin emulsion obtained in Synthesis Example 1 and a modified aliphatic polyamine (“Adeka Hardener EH-20” manufactured by Asahi Denka Co., Ltd.)
3 ″) 17 parts by weight was mixed to obtain a concrete film curing agent.

This concrete film curing agent was applied to the surface of a mortar similar to that used in Example 1 so that the film thickness would be 0.5 mm, followed by curing at room temperature for 1, 3 and 7 days, respectively, and after each curing period. The rate of change in weight of the mortar was measured to evaluate the effect of suppressing water evaporation. The results are shown in Table 1 along with the formulation, proportions and film thickness of the curing film.

Example 6 100 parts by weight of the polysulfide-modified epoxy resin emulsion obtained in Synthesis Example 2 and a modified aliphatic polyamine (“Adeka Hardener EH-20” manufactured by Asahi Denka Co., Ltd.)
3 ″) 17 parts by weight was mixed to obtain a concrete film curing agent.

This concrete film curing agent was applied to the surface of a mortar similar to that used in Example 1 so that the film thickness would be 0.5 mm, followed by curing at room temperature for 1, 3 and 7 days, respectively, and after each curing period. The rate of change in weight of the mortar was measured to evaluate the effect of suppressing water evaporation. The results are shown in Table 1 along with the formulation, proportions and film thickness of the curing film.

Comparative Example 1 For comparison, the mortar was aged at room temperature for 1, 3, and 7 days without forming a concrete curing film, and the rate of change in weight after each curing period was measured to determine the effect of suppressing water evaporation. Was evaluated. The results are shown in Table 1.

Table 1 Example 1 Example 2 Example 3 Example 4 Concrete film curing agent composition (parts by weight) Polysulfide-modified epoxy resin emulsion Emulsion of Synthesis Example 1 100 −− 100 Emulsion of Synthesis Example 2 − 100 − -Emulsion of Synthesis Example 3--100- Polyamines and polyaminoamides dispersible in water ADEKA HARDNER EH-220 10 10 12 10 ADEKA HARDNER EH-203 ----- Thickness of concrete curing film Thickness after drying (mm) 0.5 0.5 0.5 0.3 Weight change of mortar (%) Room temperature after 1 day −1.6 −1.4 −1.6 −1.9 Room temperature after 3 days −1.8 −1.6 −1.8 −2.2 Room temperature after 7 days −2.0 −1.8 −1.9 −2.6

Table 1 (continued) Example 5 Example 6 Comparative Example 1 Composition of concrete film curing agent (parts by weight) Polysulfide-modified epoxy resin emulsion Emulsion of Synthesis Example 1 100 --- Emulsion of Synthesis Example 2--100- Emulsion of Synthesis Example 3 --- Water-dispersible polyamines, polyaminoamides ADEKA HARDNER EH-220 --- ADEKA HARDNER EH-203 17 17- Thickness of concrete curing film Thickness after drying (mm) 0.5 0.5- Mortar weight change rate (%) ⁽¹⁾ Room temperature after 1 day -1.7 -1.4 -2.3 Room temperature after 3 days -1.8 -1.6 -3.8 Room temperature after 7 days -2.0 -2.0 -4.5

Note) (1): (weight of mortar after curing-weight of initial mortar) / weight of initial mortar × 100
Calculated by (%).

As is clear from Table 1, in Examples 1 to 6 in which the concrete film curing agent of the present invention was used, the reduction rate of the weight of the mortar was significantly larger than that in Comparative Example 1 in which the film curing agent was not used. It is very small and can suppress the evaporation of water.

Measurement of Moisture Evaporation Inhibitory Effect (2) Example 7 100 parts by weight of the polysulfide-modified epoxy resin emulsion obtained in Synthesis Example 3 and a modified aliphatic polyamine (“Adeka Hardener EH-22” manufactured by Asahi Denka Co., Ltd.)
0 ") 12 parts by weight was mixed to obtain a concrete film curing agent.

Next, a plastic container having a length of about 25 cm, a width of about 18 cm and a depth of about 7 cm was prepared, and 20 parts by weight of sand and 10 parts by weight of cement were placed in the plastic container.
Mix 6 parts by weight of water to a depth of 4 in a plastic container.
I put it to cm.

On the surface of the mortar thus obtained, the concrete film curing agent was applied so that the film thickness would be 0.3 mm, and it was fine and sunny in May 1991 with low humidity.
After curing for 1 day outdoors on a windy day, the weight change rate of the mortar after curing was measured. Moreover, the state of the mortar after curing was observed. The results are shown in Table 2 together with the formulation, the proportion and the film thickness of the protective film.

Comparative Example 2 For comparison, mortar was allowed to cure for 1 day outdoors on the same day as in Example 7 without forming a concrete curing film, and the rate of weight change after curing was measured. Moreover, the state of the mortar after curing was observed. The results are shown in Table 2 together with the formulation, the proportion and the film thickness of the protective film.

Comparative Example 3 As a conventional example, a vinylidene chloride-based concrete film curing agent (“Kureha delux curing agent” manufactured by Kureha Chemical Industry Co., Ltd.) was applied to the surface of a mortar similar to that of Example 7, and the film thickness was changed.
It was applied so as to have a thickness of 0.3 mm, and was applied outdoors on the same day as Example 7
After curing for a day, the weight change rate of the mortar after curing was measured. Moreover, the state of the mortar after curing was observed. The results are shown in Table 2 together with the formulation, the proportion and the film thickness of the protective film.

Comparative Example 4 100 parts by weight of a polysulfide-modified epoxy resin ("FLEP-60" manufactured by Toray Thiokol Co., Ltd.) and 27 parts by weight of modified aliphatic polyamine ("Adeka Hardener EH-220" manufactured by Asahi Denka Co., Ltd.) Parts and 5 parts by weight of ethyl acetate were mixed to obtain a concrete film curing agent.

This concrete film curing agent was applied to the surface of a mortar similar to that used in Example 7 so that the film thickness would be 0.3 mm. The weight change rate was measured. Moreover, the state of the mortar after curing was observed. The results are shown in Table 2 together with the formulation, the proportion and the film thickness of the protective film.

Table 2 Example 7 Comparative Example 2 Comparative Example 3 Comparative Example 4 Concrete film curing agent composition (parts by weight) Polysulfide-modified epoxy resin emulsion Emulsion of Synthesis Example 3 100 --- Polysulfide-modified epoxy resin FLEP-60- − − 100 Polyamines and polyaminoamides that can be dispersed in water Adeka Hardener EH-220 12 − − 27 Other components Ethyl acetate − − − Vinylidene chloride-based concrete film curing agent Klehalon latex curing agent − − 100 − Concrete curing Film thickness Film thickness after drying (mm) 0.3-0.3 0.3 Weight change rate of mortar (%) ⁽¹⁾ Outdoor, one day later -2.5 -6.4 -4.3 -3.6 Mortar condition ⁽²⁾ ○ × × × △

Note) (1): (weight of mortar after curing-weight of initial mortar) / weight of initial mortar × 100
Calculated by (%). (2): Evaluated according to the following criteria. ◯: The concrete film curing agent can be uniformly applied to the surface of the mortar, and the mortar after curing is moist and no cracks have occurred. Δ: The concrete film curing agent could not be uniformly applied to the surface of the mortar, and the part that could not be applied was dry. X: The surface of the mortar was dry. XX: The mortar was dried and large cracks occurred.

As is clear from Table 2, in Example 7 using the concrete film curing agent of the present invention, the weight change rate of mortar was small, the evaporation of water was suppressed, and the drying rate from the surface was remarkably reduced. However, in Comparative Example 2 in which no film curing agent is used and Comparative Example 3 in which a conventional concrete film curing agent is used, the mortar surface is Dried. In addition, Comparative Example 4 using a concrete film curing agent using a polysulfide-modified epoxy resin without emulsification,
Although there was an effect of suppressing the evaporation of water as compared with Comparative Examples 2 and 3, the change in weight of the mortar was larger than that of Example 7.
Further, since Comparative Example 4 uses a solvent, it is not preferable from the viewpoint of safety and environmental conservation, but the concrete film curing agent of the present invention is also excellent in this respect.

Measurement of Moisture Evaporation Inhibitory Effect (3) Example 8 A plastic container having a length of about 24 cm, a width of about 18 cm and a depth of about 7 cm was prepared and divided into 6 parts every 4 cm in the length direction. In this plastic container, 20 parts by weight of sand, 10 parts by weight of cement and 6 parts by weight of water were sufficiently mixed and placed in a plastic container up to a depth of 4 cm to prepare a mortar of 4 cm x 4 cm x 18 cm.

On the surface of the mortar thus obtained, the concrete film curing agent of Example 1 was applied so as to have a film thickness of 0.5 mm, and it was aged at room temperature for 1, 3 and 7 days, respectively. The bending strength of the mortar after the period was measured.
The results are shown in Table 3 together with the formulation, the proportion and the film thickness of the curing film.

Comparative Example 5 Mortar was aged at room temperature for 1, 3 and 7 days without forming a concrete curing film in Example 8, and the bending strength of the mortar after each curing period was measured. The results are shown in Table 3 together with the formulation, the proportion and the film thickness of the curing film.

Comparative Example 6 A vinylidene chloride concrete film curing agent (“Kureha delux curing agent” manufactured by Kureha Chemical Industry Co., Ltd.) was applied to the surface of the same mortar as in Example 8 so that the film thickness became 0.5 mm. The composition was applied and cured at room temperature for 1, 3 and 7 days, and the bending strength of the mortar after each curing period was measured. The results are shown in Table 3 together with the formulation, the proportion and the film thickness of the curing film.

Table 3 Example 8 Comparative Example 5 Comparative Example 6 Composition of concrete film curing agent (parts by weight) Polysulfide-modified epoxy resin emulsion Emulsion of Synthesis Example 1 100-- Water-dispersible polyamines, polyaminoamides ADEKA Hardener EH-220 10 − − Vinylidene chloride concrete film curing agent Klehalon latex curing agent − − 100 Concrete curing film thickness Film thickness after drying (mm) 0.5 − 0.5 Change in bending strength of mortar (kg / cm ² ) ⁽¹⁾ Room temperature after 1 day 24 15 14 Room temperature after 3 days 38 31 32 Room temperature after 7 days 48 33 40

Note) (1): Measured in accordance with JIS A1106 (1976) "Concrete bending strength test method".

As is clear from Table 3, in Example 8, the rate of flexural strength development of mortar was high, but in Comparative Examples 5 and 6, the flexural strength development rate was slow.

Measurement of Moisture Evaporation Inhibitory Effect (4) Example 9 100 parts by weight of the polysulfide-modified epoxy resin emulsion obtained in Synthesis Example 3 and modified aliphatic polyamine (Adeka Hardener EH-22 manufactured by Asahi Denka Co., Ltd.)
0 ") 12 parts by weight was mixed to obtain a concrete film curing agent.

Next, a plastic container having a length of about 25 cm, a width of about 18 cm and a depth of about 7 cm was prepared, and 20 parts by weight of sand and 10 parts by weight of cement were placed in the plastic container.
6 parts by weight of water and 0.025 parts by weight of the AE agent were sufficiently mixed and placed in a plastic container to a depth of 4 cm.

On the surface of the mortar thus obtained, the above concrete film curing agent was sprayed in an amount of 220 g /
It was applied so as to have m ² and cured at room temperature for 1 day, and the weight change rate of the mortar after curing was measured to evaluate the water evaporation suppression effect. The results are shown in Table 4 together with the formulation, proportion and film thickness of the curing film.

Example 10 100 parts by weight of the epoxy resin emulsion obtained in Synthesis Example 4 was mixed with 24 parts by weight of a modified aliphatic polyamine ("Adeka Hardener EH-220" manufactured by Asahi Denka Co., Ltd.), Used as a concrete film curing agent.

The film curing agent thus obtained was sprayed on the surface of a mortar similar to that used in Example 9 in an amount of 220 g / m 2.
^It was applied so that it would be ^2, and cured at room temperature for 1 day, and the rate of change in weight of the mortar after curing was measured to evaluate the effect of suppressing water evaporation. The results are shown in Table 4 together with the formulation, proportion and film thickness of the curing film.

Comparative Example 7 For comparison, the same mortar as in Example 9 was aged at room temperature for 1 day without forming a concrete curing film, and the weight change rate of the mortar after curing was measured to evaporate water. The inhibitory effect was evaluated. The results are shown in Table 4 together with the formulation, proportion and film thickness of the curing film.

[0089] Table 4 Example 9 Example 10 Comparative Example 7 Composition of the concrete layer Curing agent (parts by weight) polysulfide modified epoxy resin emulsion Synthesis Example 3 Emulsion 100 - - Epoxy resin emulsion Synthesis Example 4 emulsion - 100 - Water dispersible polyamines, polyaminoamides Adeka Hardener EH-220 12 24 to - application rate of thickness film curing agent concrete curing membrane ^{(g / m 2) 220 220} - weight change rate of the mortar (%) ⁽¹⁾ Room temperature after 1 day −1.0 −1.4 −2.9

Note) (1): (weight of mortar after curing-weight of initial mortar) / weight of initial mortar × 100
Calculated by (%).

As is clear from Table 4, in Examples 9 and 10 using the concrete film curing agent of the present invention, the weight reduction ratio of the mortar was lower than that of Comparative Example 7 in which the film curing agent was not used. It is significantly smaller and can suppress the evaporation of water.

Measurement of Moisture Evaporation Inhibitory Effect (5) Example 11 A concrete formwork having a depth of 4 cm, a width of 4 cm and a length of 16 cm was prepared, and 20 parts by weight of sand, 10 parts by weight of cement and 4.5 parts of water were prepared in the concrete formwork. Part by weight and 0.025 part by weight of the AE agent are mixed well and packed at 550 g per frame, and the surface is made uniform with a brush.
A mortar measuring cm × 4 cm × 16 cm was prepared.

After leaving this mortar at 20 ° C. for 1 hour,
The solid content of the concrete film curing agent of Example 3 was 70 g / m ^2.
Was applied for 20 days at 20 ° C., and the mortar was measured for bending strength after each curing period.
The results are shown in Table 5 together with the formulation, proportions and film thickness of the curing film.

Comparative Example 8 In Example 11, without forming a concrete curing film,
It was cured at 20 ° C. for 2 days and 21 days, respectively, and the bending strength of the mortar after each curing period was measured. The results are shown in Table 5 together with the formulation, proportions and film thickness of the curing film.

Comparative Example 9 A mortar prepared in the same manner as in Example 11 was allowed to stand at 20 ° C. for 1 hour, and then the film curing agent of Comparative Example 6 was applied so that the solid content was 70 g / m ² , and the temperature was 20 ° C. Were cured for 2 days and 21 days respectively, and the bending strength of the mortar after each curing period was measured. The results are shown in Table 5 together with the formulation, proportions and film thickness of the curing film.

Comparative Example 10 A mortar prepared in the same manner as in Example 11 was allowed to stand at 20 ° C. for 1 hour, and then a synthetic resin film curing agent (“Hardcoat CL-E1” manufactured by Aoi Chemical Industry Co., Ltd.) was added to the solid content. Is 70 g / m ²
It was applied so that it was cured at 20 ° C. for 2 days and 21 days, and the bending strength of the mortar after each curing period was measured.
The results are shown in Table 5 together with the formulation, proportions and film thickness of the curing film.

Table 5 Example 11 Comparative example 8 Comparative example 9 Comparative example 10 Concrete film curing agent composition (parts by weight) Polysulfide-modified epoxy resin emulsion Emulsion of Synthesis example 3 100 --- Polyamines dispersible in water, Polyaminoamides Adeka Hardener EH-220 12 − − − Vinylidene chloride concrete film curing agent Klehalon latex curing agent − − 100 − Synthetic resin film curing agent Hard coat CL-E1 − − − 100 Coating film thickness of concrete curing film (g / m ² : solid content conversion) 70-70 70 Change in bending strength of mortar (kg / cm ² ) ⁽¹⁾ 20 ° C ・ 2 days later 44 37 38 40 40 20 ° C ・ 21 days later 50 44 44 44 44

Note) (1): Measured in accordance with JIS A1106 (1976) "Concrete flexural strength test method".

As is apparent from Table 5, Comparative Examples 8 to 8
The bending strength after 10 days of curing for 21 days is obtained in Example 11 by curing for 2 days, and it is understood that the use of the film curing agent of the present invention causes the flexural strength of the mortar to develop rapidly.

[0100]

As described above in detail, in the present invention,
As a concrete film curing agent by reacting an emulsion of an epoxy resin (preferably polysulfide-modified epoxy resin) containing a bisphenol skeleton in the molecule with an epoxy group at the end, and a polyamine or polyaminoamide dispersible in water. There is.

The film curing agent thus obtained has toughness and high water vapor barrier properties. In particular, the concrete film curing agent obtained by using the polysulfide-modified epoxy resin emulsion is further improved in toughness and water vapor barrier property and is also excellent in chemical resistance, durability, and adhesiveness. In addition, this concrete film curing agent suppresses the amount of water evaporation from the concrete surface in the early stage of hardening, even for concrete that has been driven in when the temperature is high or the humidity is low, and it is necessary to construct high-strength concrete with high durability. You can

Further, the concrete film curing agent of the present invention comprises
There is no need to sprinkle water each time the concrete surface dries, and the work is simple, and once applied, it can be left unattended, which saves time and effort.

The concrete film curing agent of the present invention can be used for curing concrete in a wide area such as an airfield or a highway. Even in a structure with a large exposed area such as a concrete pavement, the amount of water vapor generated at the initial stage of curing can be improved. Can be suppressed. Further, even in the case of concrete constructed in cold regions, which are vulnerable to freezing damage or salt damage, or on the sea or on the coast, the amount of water mixed can be controlled, and concrete with good durability can be obtained.

Further, the concrete film curing agent of the present invention comprises
For construction such as road pavement where it is difficult to cut off traffic for a long period of time, concrete can be raised to practical strength early to shorten the construction period.

The concrete film curing agent of the present invention has a great effect of preventing moisture evaporation of concrete, and does not require the setting of a curing mat. Furthermore, even after the concrete is poured, that is, even when the concrete surface is covered with water, it becomes a complete curing film.

Since the concrete film curing agent of the present invention does not use a solvent or a diluent, it is excellent in safety and environmental protection.

The concrete film curing agent of the present invention as described above is used for an airfield, a highway, an embankment, a harbor facility, a large building, a bridge, a container yard, a truck terminal in which a high strength concrete having a wide area and high durability is essential. Suitable for curing concrete to be constructed in cold regions or roads in mountains.

Claims (4)

[Claims] 1. A method comprising: (A) an epoxy resin emulsion having an epoxy group at the terminal and containing an epoxy resin containing a bisphenol skeleton in the molecule; and (B) a polyamine or polyaminoamide dispersible in water. A concrete film curing agent. 2. The concrete film curing agent according to claim 1, wherein the epoxy resin has the following general formula: (However, R ₁ and R ₃ are organic groups having a bisphenol skeleton, and R ₂ is an organic group having a sulfur atom.) A polysulfide-modified epoxy resin represented by Agent. 3. A concrete film curing agent comprising (A) an epoxy resin emulsion containing an epoxy resin having a bisphenol skeleton in the molecule and having an epoxy group at the end, and (B) a polyamine or polyaminoamide dispersible in water. A method for curing concrete, characterized in that a concrete curing film is formed by applying the agent to the concrete surface after construction, and the evaporation amount of water from the concrete in the initial stage of curing is suppressed. 4. The method for curing concrete according to claim 3, wherein the epoxy resin has the following general formula: (However, R ₁ and R ₃ are organic groups containing a bisphenol skeleton, and R ₂ is an organic group containing a sulfur atom.) A polysulfide-modified epoxy resin represented by Method.