JPH0749580B2 - Soil moistureproofing agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a moisture-proof treatment agent for soil that is sprayed on the soil under the floor of a house.

(Prior Art) Conventionally, as a moisture-proofing agent for soil sprayed on the soil under the floor of a house, for example, a soil moisture-proofing agent as disclosed in JP-A-61-43693 by the inventor of the present application is known. . This is styrene containing 20 to 70% by weight of styrene component.
(Meth) acrylic ester type copolymer resin emulsion (A) and gypsum (B), and mixing ratio of styrene- (meth) acrylic acid ester type copolymer resin emulsion (A) and gypsum (B) [(A) to (B)] is configured to have a solid content weight ratio of 2/98 to 40/60. By spraying this soil dehumidification treatment agent on the surface of the target soil, a coating film is formed on the surface of the soil, and this coating film blocks moisture evaporating from the soil, whereby the underfloor portion of the wooden house is It is intended to prevent the underfloor from decaying in a short period of time or from being damaged by termites in order to prevent it from becoming moist.

However, since the coating film formed by the conventional soil moistureproofing agent has fine capillary-like pores, the water content of the target soil becomes supersaturated, and When the formed water surface and the coating film are in contact with each other, due to the capillary phenomenon, moisture is absorbed through the capillary and rises in water, and the upper surface of the coating film becomes wet. It was found that the moisture absorption effect was not sufficient, as a result of the increase in water vapor and the underfloor part became moist.

(Object of the invention) In view of the above situation, the present invention provides a method for forming a coating by chemical spraying even when the water in the target soil is supersaturated and a water surface is formed on the surface of the soil. A soil moisture-proofing agent that can prevent moisture from being blocked by the covering film, and can prevent the underfloor part of a wooden house from becoming moist, causing the underfloor part to decay in a short period of time or be damaged by termites. It is intended to provide.

(Structure of the Invention) The present invention is a styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) having a styrene content of 20 to 70% by weight, gypsum (B), and a molecular weight of 500 to 1500. And a petroleum-based resin emulsion (C) having a softening point of 40 to 60 ° C., and a mixing ratio of styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) and gypsum (B) [(A) (B)] is a solid content weight ratio of 2 to 98 to 40 to 60
The petroleum-based resin emulsion (C) has a solid content of 25 to 75% by weight based on the solid content of the styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) to which the gypsum (B) is added. % Solids are mixed together.

In the coating film formed by the soil moistureproofing agent having the above structure, the capillaries that were present in the coating film formed by the conventional soil moistureproofing agent are sealed by the oil component of the petroleum-based resin emulsion of the present invention. Therefore, even if the lower surface of the coating film and the water surface of the soil surface are in contact with each other, the increase in water content due to the capillary phenomenon can be stopped.

(Example) A soil moisture-proofing agent according to the present invention comprises a styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A),
It is composed of gypsum (B) and petroleum resin emulsion (C).

The styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) has a styrene content of 20 to 70.
It means a styrene / (meth) acrylic acid ester-based copolymer resin emulsion in the range of 30% by weight, preferably 30 to 50% by weight.

Examples of the (meth) acrylic acid ester include acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, octyl acrylate and 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate and Methacrylic acid esters such as octyl methacrylate are used.

When the content of styrene component in styrene and (meth) acrylic acid ester-based copolymer resin is less than 20% by weight, the coating film formed by the soil moisture-proofing agent containing this is too soft and the strength is insufficient. On the other hand, when the content of styrene component is more than 70% by weight, the coating film formed by the soil moistureproofing agent containing this is hard and brittle, and the elasticity and impact resistance are poor, so that the moisture It is difficult to get the effect.

The styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) is produced by a conventional method, for example, by radically copolymerizing a monomer in water in the presence of a surfactant, a protective colloid, or a polymerization initiator. It

Further, in the present invention, not only styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A), but also styrene, (meth) acrylic acid ester, and a third component such as acrylic acid, methacrylic acid, Itaconic acid, acrylamide, 2-hydroxyethyl acrylate, maleic acid, dibutyl maleate, dihinylbenzene, N-methylol acrylamide, glycidyl methacrylate, triallyl cyanurate, copolymerized with ethylene glycol dimethacrylate can also be used. it can. If dihinylbenzene, triallyl cyanurate, ethylene glycol dimethacrylate or the like is used in the third component, an already crosslinked synthetic resin emulsion is obtained, and if N-methylolacrylamide, glycidyl methacrylate or the like is used as the third component. A self-crosslinking synthetic resin emulsion is obtained. The ratio of these third components to the resin is 0.1-5% by weight
Is desirable.

Further, the styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) contains a film-forming aid or plasticizer usually used in emulsion paints such as ethylene glycol monobutyl ether, diethylene glycol monobutyl acetate, texanol, dibutyl phthalate. , Dioctyl phthalate and the like may be blended as necessary, and a curing accelerator such as calcium chloride may be blended to accelerate the curing. In addition, styrene- (meth)
Acrylic ester-based copolymer resin emulsion (A) may contain glycols such as ethylene glycol and propylene glycol, various surfactants, or natural or synthetic polymer substances such as hydroxyethyl cellulose, methyl cellulose and polyvinyl alcohol, if necessary. May be compounded to delay curing.

Next, as gypsum (B), gypsum dihydrate, α hemihydrate gypsum, β
Hemihydrate gypsum and the like may be used alone or in admixture of two or more.

The mixing ratio of the gypsum (B) and the styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) is 2 to 98 in terms of solid content weight ratio as copolymer resin emulsion (A) to gypsum (B). 40 to 60, preferably 5 to 95-30
The pair is 70. The mixing ratio of the copolymer resin emulsion (A) is smaller than the above-mentioned 2 to 98 in terms of solid content weight ratio, that is, 2
If the amount is less than the above, the curing is fast, but the coating film is hard and brittle, is inferior in elasticity and impact resistance, and the water absorption rate is increased to deteriorate the moisture-proof and waterproof functions. On the other hand, the mixing ratio of the copolymer resin emulsion is more than 40:60 in the solid content weight ratio, that is,
When it is more than 40, not only the curing slows down, the hardness of the coating film is lost and the strength becomes insufficient, but also the dimensional stability is poor.

The petroleum resin emulsion (C) is a cationic, anionic or nonionic petroleum resin having a molecular weight of
An emulsion obtained by emulsifying one having a softening point in the range of 500 to 1500 and 40 to 60 ° C. is used, and the solid content of the petroleum resin emulsion (C) is the styrene- (meth) acrylic acid ester copolymer resin emulsion. Gypsum on (A) (B)
The soil moisture-proofing agent is constituted by mixing 25 to 75% by weight, and preferably 50% by weight, of the solid content with that to which the above is added.

A general cation type petroleum-based resin shows a tendency to aggregate when mixed and used because the styrene- (meth) acrylic acid ester type copolymer resin emulsion (A) is an anionic type, and thus the coating film Although it is advantageous in forming, it requires careful handling during spraying. Anion type petroleum resins are preferable because the styrene- (meth) acrylic acid ester type copolymer resin emulsion (A) is the same anion type. In particular, an anionic type and a nonionic type are preferable in terms of excellent dispersibility when mixed and used.

A low molecular weight compound having a molecular weight within the above range has adhesiveness and can exhibit moisture resistance and waterproofness by filling the capillary portion of the coating film and firmly integrating them. On the contrary, for example, the high molecular weight of 10,000 has no adhesiveness,
The coating film formed by the soil moistureproofing agent mixed with this causes cracks and cannot exhibit moistureproofness and waterproofness.

When the softening point is lower than the above range, the coating film formed by the soil moistureproofing agent mixed with the petroleum-based resin emulsion has tackiness even after curing, and therefore the surface is sticky and practical for working under the floor. On the other hand, when the softening point is higher than the above range, the coating film formed by the soil moisture-proofing agent mixed with the petroleum-based resin emulsion has a softening point in comparison with the case where the softening point is within the predetermined range. Inferior in moisture resistance and waterproofness.

When the mixing ratio of the petroleum-based resin emulsion (C) is smaller than the above range, the coating film formed by the mixed soil moistureproofing agent is more moisture-proof and waterproof than when the mixing ratio is within the predetermined range. On the other hand, when the mixing ratio is larger than the above range, the coating film formed by the mixed soil moistureproofing agent has no problem in high moisture resistance and waterproofness, but the coating film is poor in strength. When working under the floor after formation, the work cannot be walked on the coating film, which significantly restricts the work.

Specific examples of petroleum-based resins or petroleum-based resin emulsions used include petrozine (trade name of Mitsui Petrochemical Co., Ltd., softening point 80 to 130 ° C., molecular weight 500 to 1100),
Toho Petrosin QME100 (trade name of Toho Petroleum Resin Co., Ltd., softening point 95 ° C, average molecular weight 900, anionic), Toho Petrosin QME60 (trade name of Toho Petroleum Resin Co., Ltd., softening point 60 ° C,
Average molecular weight 900, anionic), WEK7 (Toa Road Industrial Co., Ltd., softening point 43 ° C, molecular weight 50-1100, anionic),
Fujilag (Fuji Kosan Co., Ltd., softening point 40 ° C, molecular weight 600,
Cationic), etc., and one or two or more selected from these are mixed and the one set so that the softening point is 40 to 60 ° C. is used. Here, the petroleum resin can be emulsified by heat-melting it in the presence of a surfactant.

In the soil moistureproofing agent having the above-mentioned configuration, various chemicals for controlling termites may be mixed, or various appropriate germicides for preventing decay due to Namitake mushrooms may be blended. In addition to this, ant and antiseptic measures can be taken together.

In addition, sand, aggregates, pigments, cements, surfactants, thickeners, defoamers and the like may be added to the soil moistureproofing agent, if necessary.

As sand and aggregates, quartz, perlite, vermiculite, shirasu balloon, silica stone powder, silica sand, river sand, etc.
Kaolin, talc, clay, various calcium carbonates, titanium oxide, mica, acid clay, diatomaceous earth, iron powder, ferrite, lithopone, baryta, zirconia, carbon black, white carbon and the like can be used. As the cements, various Portland cements, blast furnace cements, alumina cements and the like can be used. The sand, aggregates, pigments and cements may be used alone or in combination of two or more. The addition amount of these is 100 parts by weight based on 100 parts by weight of the total amount of the styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) and the gypsum (B) in the soil moisture-proofing agent. The amount is preferably 300 parts by weight or less, and more preferably 100 parts by weight or less.

As the thickener, a natural polymer thickener such as gelatin or casein, starch treated with oxidation, methylation, carboxymethylation, hydroxyethylation, hydroxypropylation, phosphorylation or cationization,
Semi-synthetic polymeric thickeners such as cellulose, sodium alginate or ammonium alginate, synthetic polymeric thickeners such as polypinyl alcohol, polyvinylpyrrolidone, sodium polyacrylate or polyacrylamide,
Surfactant-based thickeners such as polyethylene oxide or its derivatives, and inorganic-based thickeners such as colloidal silica, bentonite, and atagel can be used. By using this thickener, the workability at the time of spraying the soil moistureproofing agent can be adjusted.

The amount of this thickener compounded is 0.
The range of 01 to 3% by weight is preferable, and when the content of the thickener is smaller than this range, aggregates and pigments tend to settle in a short period of time, and when the content of the thickener is larger than the above range. May reduce the water resistance of the coating film.

As the defoaming agent, octyl alcohol, capryl alcohol, lauryl alcohol, cyclohexanol, etc. can be used, and this defoaming agent is based on 100 parts by weight of styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A). It is preferable to add about 0.001 to 1 part by weight.

In the soil moistureproofing agent blended with the additives as described above, the amount of nonvolatile components in the soil moistureproofing agent is usually 30 ~.
The range of 80% by weight is preferable, and when the amount of nonvolatiles exceeds 80% by weight, workability during spraying deteriorates, and conversely, when the amount of nonvolatiles is lower than 30% by weight, the soil dehumidifying agent is applied to the soil. The permeation rate of the above becomes too large, and it becomes difficult to form a coating film, and the moisture-proof effect is reduced.

Next, a procedure for performing moisture proofing and waterproofing treatment on the soil surface under the floor of a wooden house using the soil moisture proofing agent having the above configuration will be described. First, add water to the soil moistureproofing agent and dilute it so that the weight ratio becomes 1.5 times. As a result, the soil moistureproofing agent has a viscosity of 10 to 20,000 cP (centipoise), preferably about 100 to 10,000 cP. When the viscosity is higher than the above range, workability during spraying is poor, and the uniformity of the coating film after spraying is low, which makes it difficult to form a uniform coating film. On the other hand, if the viscosity of the soil moisture-proofing agent is lower than the above range, the permeability to the soil becomes too large, and the tightness of the coating film is lacking, so that it is difficult to obtain a predetermined moisture-proofing and waterproofing effect. Then, the soil moistureproofing agent is sprayed or applied on the surface of the target soil under the floor to form a coating film on the soil surface. That is, as the water evaporates from the surface of the dispersion layer, a film is formed on the surface of the dispersion layer, and the film becomes dense over time, whereby a moisture-proof and waterproof coating film is formed. This coating film is formed 1 to 3 days after spraying, and 7 to 21 days after spraying, the moisture-proof and waterproof effects are exerted. At this time, the film thickness of the coating film when cured and dried is preferably 0.2 mm or more, and particularly preferably in the range of 0.4 to 2 mm. If the film thickness is too small, the moisture-proof and waterproof effects are low. Conversely, even if the film thickness is increased, the moisture-proof and preventive effects proportional to the film thickness cannot be obtained.
It wastes materials and is uneconomical.

Next, specific examples and comparative tests using the examples will be described based on Table 1.

Table 1 shows the blending ratios of Examples 1 to 9 and Comparative Examples 1 to 3 and the test results when these Examples and Comparative Examples were used.

Soil dehumidification treatment agent used in the comparison test, using the one that was diluted to 1.5 times the weight ratio by adding water to the examples showing the mixing ratio in Table 1, 2Kg / m ² soil dehumidification treatment agent equivalent amount. Sprayed.

The moisture-proof rate α shown in Table 1 was determined by the procedure described below. First, 300 ml of glass beaker is filled with 300 ml of sand (No. 7 silica sand), and the glass tube is fixed to the inner peripheral surface of this glass beaker so that the lower end is located at the bottom of the glass beaker.
By injecting water from this glass tube, the water surface reaches the surface of the sand in the glass beaker, and the sand is supersaturated. The sample in this state was treated as an untreated sample in a 100% saturated state. On the other hand, the amount of water injected until this state was measured and 75% of that amount was used. The injected sample was used as an untreated specimen in a 75% saturated state. Next, 2 Kg /
An amount equivalent to m ² of the above-mentioned soil moistureproofing agent was sprayed. This sample is left at room temperature to dry the surface of the coating film, and the water content of the surface of the coating film is measured by a water content meter using electric resistance.When the water content reaches 25%, the water content is measured again. Water was injected through the glass tube and corrected to have the same weight as before drying. This state was used as a processed specimen. This is because the weight decreased due to drying may have evaporated in the water contained in the sand in addition to the water contained in the soil dehumidification treatment agent, and the water content was corrected to the total weight before drying. This prevents the test results from appearing larger than they actually are. The weight of the untreated specimen and the treated specimen is measured to start the test, and the specimen is left in an air-dried state for one day, and then the respective weights are measured again. By subtracting this weight from the weight at the start of the test, the amount of evaporated water in one day
Find W ₀ , W. Based on these weights, the moisture-proof rate α (%) is determined by α = {(W ₀ −W) / W ₀ } × 100. Here, W ₀ indicates the amount of evaporated water per day from the untreated specimen (g / day), and W indicates the amount of evaporated water per day from the treated specimen (g / day). . This moisture-proof rate α was determined for two types of soil, one for one example, that is, a state in which 100% sand was saturated with water and 75% with sand.

In Table 1, (A) is a styrene- (meth) acrylic acid ester-based copolymer resin emulsion, (B) is gypsum,
(C) shows a petroleum-based resin emulsion. As the petroleum-based resin emulsion (C), in Examples 1 to 5, anionic ones having a softening point of 43 ° C, in Example 6 cationic ones having a softening point of 40 ° C, and in Example 7, nonionic softening points. 45 ° C., Example 8 is anionic and has a softening point of 53 ° C.
In Example 9, an anion type having a softening point of 57 ° C. was used, and in a comparative example, an anionic type having a softening point of 95 ° C. was used.

Next, the test results will be examined.

In Comparative Examples and Comparative Examples not containing the petroleum resin emulsion (C) of the present invention, as shown in Table 1,
It has a high moisture-proof effect on soil that is 75% saturated, but it has no moisture-proof effect on soil that is 100% saturated, and has no coating film formed. It can be seen that the same amount of water vaporized between the sample and the treated sample on which the coating film was formed. This tendency was the same in Comparative Examples and Comparative Examples even if the compounding ratios of the styrene- (meth) acrylic acid ester copolymer resin emulsion (A) and the gypsum (B) were different.

Further, even in a comparative example in which a petroleum-based resin emulsion having a softening point outside the range of the softening point of the petroleum-based resin emulsion (C) of the present invention is mixed, a high moisture-proof effect is obtained for 75% saturated water soil. Although it did, it showed almost no moisture-proof effect on 100% saturated soil, and the amount of water that did not change much from the amount of water evaporated in the untreated sample without the coating film evaporated. I understand.

From the test results of Examples 1 to 3 or Examples 4 and 5, if the other conditions are the same, the larger the amount of the petroleum-based resin emulsion (C) is, the more the test results of Examples 2, 8 and 9 are. From the above, it can be seen that if the other conditions are the same, the lower the softening point is, the higher the moisture-proof effect is. As for the petroleum-based resin emulsion (C) system, it can be seen from Examples 6 to 8 that the cationic system exhibits the highest moisture-proof effect.

(Effect of the invention) According to the soil moistureproofing agent of the present invention, the coating film formed by spraying this soil moistureproofing agent on the surface of the target soil is a coating formed by a conventional soil moistureproofing agent. The membrane
The petroleum-based resin emulsion according to the present invention is in a sealed state with the oil component.

Therefore, even if the water in the target soil becomes supersaturated and a water surface is formed on the surface of the soil and the lower surface of the coating film and the water surface of the soil surface are in contact, the water increase due to the capillary phenomenon is suppressed. It is possible to prevent evaporation of water by the coating film.

Therefore, it is possible to prevent the underfloor portion of the wooden house from decaying in a short period of time or being damaged by termites due to moisture under the floor portion.

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Claims (1)

[Claims] 1. A styrene- (meth) acrylic acid ester copolymer resin emulsion (A) having a styrene content of 20 to 70% by weight, gypsum (B), and a molecular weight of 500 to 1500.
And a petroleum-based resin emulsion (C) having a softening point of 40 to 60 ° C., and a mixing ratio of styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) and gypsum (B) [(A) To (B)] is a solid content weight ratio of 2 to 98 to 40
60, and the petroleum-based resin emulsion (C) has a solid content of styrene- (meth) acrylic acid ester-based copolymer resin emulsion (A) to which gypsum (B) is added.
A soil moisture-proofing agent, wherein 25 to 75% by weight of the solid content is mixed.