JP3181573B1 - Paint for soil adhesion inhibitor, steel sheet pile for soil adhesion prevention and soil adhesion prevention method using them - Google Patents

Abstract

An object of the present invention is to provide a paint for a soil adhesion preventing agent, which makes it difficult for soil to adhere to a temporary steel material which is drawn and collected after construction, and which is coated with the soil adhesion preventing agent in advance. Provided steel sheet piles and a method for preventing soil adhesion using the sheet piles. SOLUTION: A paint for an anti-adhesion agent containing a water-absorbent resin (a), a hydrophilic binder resin (b) and a solvent (c) as essential components of the present invention is applied to a temporary steel material in advance and applied.
By this construction form, it can be easily constructed on temporary steel buried in the ground, hardly peels off from the base material at the time of placing the temporary steel underground, and between the steel material and the surrounding ground when pulling out the temporary steel material By lowering the adhesion, there is little adverse effect such as raising the surrounding ground, and almost no soil adheres to the temporary steel material after drawing, and the void after pulling out the temporary steel material is minimized (substantially the same as the volume of the temporary steel material itself). ), The amount of chemicals and sediment used for post-processing (backfilling) is minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a temporary steel material which is drawn and recovered after construction, such as a steel sheet pile, which is often used in an underground excavation using a retaining wall and a method of burying a foundation structure. By so doing, the paint for the soil adhesion preventing agent, which makes it difficult for the soil to adhere to the temporary steel material after the drawing, the steel sheet pile for soil adhesion prevention coated with the soil adhesion preventing agent in advance, and the paint for the soil adhesion preventing agent, and / or Also, the present invention relates to a method for preventing soil adhesion using a steel sheet pile for preventing soil adhesion.

[0002]

2. Description of the Related Art Conventionally, underground excavation using a retaining wall,
Temporary steel materials such as steel sheet piles, which are often used in the burying method of foundation structures, have a problem that soil adheres after drawing and collecting.

[0003] The temporary steel material (for example, steel sheet pile) to which the soil has adhered after the recovery cannot be piled up in parallel after the recovery, so that the temporary steel material after the recovery is difficult. Since it is premised that the soil will adhere to the temporary steel material when returning the temporary steel material to the leasing company, there is a problem in that cleaning costs must be paid. Therefore, under the present circumstances, the construction company usually removes the adhered soil manually or pays a high cleaning cost to the leasing company.

[0004] In order to solve this problem, the following techniques have been proposed. First, JP-A-6-71
No. 241, a steel sheet pile mud removal line (device) comprising a mud removing device, an earth discharging device, and a water washing device is disclosed in JP-A-6-330521. Debris removal equipment for the section has been proposed, but in each case a new device must be installed, and the efficiency of the work to remove the deposited soil may be improved, but the removal work itself is required. It did not essentially solve the mud adhesion problem.

[0005] Japanese Patent Publication No. 61-47253 and
In Japanese Patent Application Laid-Open No. 0-175628 and Japanese Patent Laid-Open No. 3-279516, a scraper attached to the shape of a steel sheet pile is buried adjacent to the steel sheet pile before backfilling after excavation work. It has been proposed to suppress deformation of a buried pipe or the like due to soil attached to a sheet pile.

However, in this method, the adhesion of the soil remaining in the gap between the scraper and the steel sheet pile cannot be prevented. Since the scraper is set at the lower part of the buried underground, the adhesion of the soil above the scraper cannot be prevented. There is a problem that it takes time to create and set up according to the shape.

As described above, regardless of the shape of the buried temporary steel material, the construction is simple and the washing after the drawing can be omitted so that the temporary steel material after the drawing hardly adheres to the soil. There was no soil adhesion prevention method.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to easily construct a temporary steel material buried in the ground, At the time of casting, it hardly peels off from the base material, and at the time of pulling out the temporary steel material, by lowering the adhesion between the steel material and the surrounding ground, there is little adverse effect such as lifting up the surrounding ground. Has almost no soil adhesion, and the void after the temporary steel material is pulled out is minimized (substantially equal to the volume of the temporary steel material itself).
An object of the present invention is to provide a paint for an anti-adhesion agent which requires a minimum amount of chemicals and sand required for post-processing (backfilling).

Still further, a steel sheet pile for preventing soil adhesion to which the above-mentioned paint for soil adhesion inhibitor has been applied in advance, and a method for preventing soil adhesion using the paint for soil adhesion inhibitor and / or the steel sheet pile for preventing soil adhesion. It is to provide.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, the inventor of the present invention can easily construct a temporary steel material buried in the ground, and when the temporary steel material is cast into the ground, There is almost no peeling, and when pulling out the temporary steel material, the adhesiveness between the steel material and the surrounding ground is reduced, so that there is little adverse effect such as raising the surrounding ground, and almost no soil adheres to the temporary steel material after drawing. Since the voids after the drawing of the temporary steel material are minimized (substantially the same as the volume of the temporary steel material itself), the agent required for post-processing (backfilling) and the soil adhesion inhibitor that minimizes the amount of sediment used Diligently studied paints for use.

As a result, it is necessary to preliminarily apply a paint for an anti-fouling agent containing the water-absorbent resin (a), the hydrophilic binder resin (b) and the solvent (c) as essential components to a temporary steel material buried underground. As a result, the inventors have found that the above problems can be solved, and have completed the present invention.

First, the paint for soil adhesion inhibitor of the present invention will be described below. The water-absorbent resin (a) used in the present invention swells by absorbing water, and is particularly a resin having a water absorption ratio of 3 times or more (25 ° C., 1 hour) with respect to its own weight. Not limited. However, a synthetic water-absorbent resin obtained by crosslinking a water-soluble or hydrophilic compound (monomer and / or polymer) with a crosslinking agent, as exemplified below, has a higher swelling ratio and water These are more preferable than natural water-swellable substances (gelatin, agar, etc.) because the balance between soluble matter, water absorption rate, strength and the like is good and the balance can be easily adjusted.

The water-absorbing resin (a) as described above includes
Specifically, for example, cross-linked poly (meth) acrylic acid,
Cross-linked poly (meth) acrylate, cross-linked poly (meth) acrylate having a sulfonic group, cross-linked poly (meth) acrylate having a polyoxyalkylene group, cross-linked poly (meth) acrylamide, Meta)
Crosslinked copolymer of acrylate and (meth) acrylamide, hydroxyalkyl (meth) acrylate and (meth)
Cross-linked copolymer with acrylate, cross-linked polydioxolane, cross-linked polyethylene oxide, cross-linked polyvinyl pyrrolidone, cross-linked sulfonated polystyrene, cross-linked polyvinyl pyridine, saponified starch-poly (meth) acrylonitrile graft copolymer, starch- Poly (meth) acrylic acid (salt) graft crosslinked copolymer, reaction product of polyvinyl alcohol and maleic anhydride (salt), crosslinked polyvinyl alcohol sulfonate, polyvinyl alcohol-acrylic acid graft copolymer, polyisobutylene maleic Acid (salt) cross-linked polymers and the like. One of these water-absorbing resins may be used alone, or two or more thereof may be used in combination.

In the present invention, it is preferable to use a salt-resistant water-absorbing resin as the water-absorbing resin (a). The reason why the salt-resistant water-absorbent resin is preferable is that the salt-resistant water-absorbent resin has a relatively high water absorption ratio of hard water containing a polyvalent metal, and when used in a paint for an anti-fouling agent, it has little effect on the water quality in the soil. This is because the effect of preventing soil adhesion can be exerted without being affected.

The salt-resistant water-absorbent resin of the present invention is not particularly limited as long as it has a water absorption capacity of 10 times or more in artificial seawater (25 ° C., 24 hours). Among the resins (a), those having a nonionic group and / or a sulfonic acid (salt) group are more preferable, and those having an amide group or a hydroxyalkyl group are still more preferable. As the salt-resistant water-absorbing resin as described above,
For example, a cross-linked copolymer of (meth) acrylate and (meth) acrylamide, a cross-linked copolymer of hydroxyalkyl (meth) acrylate and (meth) acrylate, and the like can be given. Further, those having a polyoxyalkylene group are particularly preferred. Examples of such a water-absorbent resin (a) include a crosslinked copolymer of a (meth) acrylate having a methoxypolyoxyalkylene group and a (meth) acrylate.

These salt-resistant water-absorbing resins can use the water-absorbing resin to obtain properties of water in the soil (soft water, hard water, etc.).
Swells to a certain magnification regardless of the temperature, and can more reliably exhibit the soil adhesion preventing function.

Furthermore, the water-absorbent resin (a) according to the present invention
The method for producing is not particularly limited, and examples thereof include a method of polymerizing a monomer component containing a water-soluble ethylenically unsaturated monomer and, if necessary, a crosslinking agent. The water-absorbent resin (a) obtained by (co) polymerizing an ethylenically unsaturated monomer is more excellent in water absorbency with respect to water, and
Generally inexpensive. In addition, the above-mentioned crosslinking agent is not particularly limited.

The above ethylenically unsaturated monomers include:
Specifically, for example, acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, citraconic acid, vinylsulfonic acid, (meth) allylsulfonic acid,
2- (meth) acrylamide-2-methylpropanesulfonic acid, 2- (meth) acryloylethanesulfonic acid,
2- (meth) acryloylpropanesulfonic acid, and alkali metal salts and ammonium salts of these monomers;
N, N-dimethylaminoethyl (meth) acrylate,
And quaternary compounds thereof; (meth) acrylamide, N,
(Meth) acrylamides such as N-dimethyl (meth) acrylamide, 2-hydroxyethyl (meth) acrylamide, diacetone (meth) acrylamide, N-isopropyl (meth) acrylamide, (meth) acryloylmorpholine, and monomers thereof A hydroxyalkyl (meth) acrylate such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, methoxypolyethylene glycol mono ( Polyalkylene glycol mono (meth) acrylates such as meth) acrylate and methoxy polypropylene glycol mono (meth) acrylate; N-vinyl-
N-vinyl monomers such as 2-pyrrolidone and N-vinylsuccinimide; N-vinylformamide, N-vinyl-N
-Methylformamide, N-vinylacetamide, N-
N-vinylamide monomers such as vinyl-N-methylacetamide; vinyl methyl ether; and the like, but are not particularly limited. These ethylenically unsaturated monomers may be used alone or in combination of two or more.

Among the ethylenically unsaturated monomers exemplified above, those composed of an ethylenically unsaturated monomer having a nonionic group and / or a sulfonic acid (salt) group are more preferred because of their high salt resistance. Examples of the monomer include 2
-(Meth) acrylamide-2-methylpropanesulfonic acid, 2- (meth) acryloylethanesulfonic acid, 2
-(Meth) acryloylpropanesulfonic acid, (meth)
Acrylamide, hydroxyalkyl (meth) acrylate, methoxypolyethylene glycol mono (meth) acrylate and the like can be mentioned. Further, an ethylenically unsaturated monomer having a polyoxyalkylene group is particularly preferred.

When two or more ethylenically unsaturated monomers are used in combination as the monomer component, a more preferable combination is, for example, a combination of an alkali metal (meth) acrylate such as sodium acrylate and acrylamide. And a combination of an alkali metal salt of (meth) acrylic acid and methoxypolyethylene glycol mono (meth) acrylate, but are not particularly limited.

By polymerizing the above monomer components,
The water-absorbent resin (a) is obtained. In addition, the water absorbent resin (a)
The average molecular weight and shape, the average particle diameter, etc., may be set according to the composition of the soil adhesion inhibitor paint and the type of binder, physical properties, work environment, etc., but is not particularly limited,
The average particle size of the water-absorbent resin (a) is preferably from 30 to 800 μm, more preferably from 30 to 600 μm, and from 30 to 40 μm.
0 μm is most preferred.

When the average particle size of the water-absorbent resin (a) used in the present invention exceeds 800 μm, the particle size is too large, and the water-absorbent resin (a) is added to the solvent (c) solution of the hydrophilic binder resin (b). When mixed, the particles of the water-absorbent resin (a) tend to settle, which is not preferable. On the other hand, if the average particle size of the water-absorbent resin (a) is less than 30 μm, handling becomes extremely difficult (such as easy scattering as fine powder), which is not preferable.

Next, the hydrophilic binder resin (b) that constitutes the paint for soil adhesion inhibitor of the present invention will be described.

The hydrophilic binder resin (b) used in the present invention is water-soluble or water-swellable, has a function of fixing the water-absorbent resin (a) to the substrate as a binder, and has a solvent ( Although it is not particularly limited as long as it dissolves in c), for example, (meth) acrylate copolymer, polyurethane, polyester, polycarbonate, polyvinyl alcohol-based resin, polyvinyl acetate partial hydrolyzate, Examples thereof include an ethylene-polyvinyl alcohol copolymer, and a mixture of one or more of these can be used.

When the hydrophilic binder resin (b) has too low hydrophilicity, the swelling of the water-absorbent resin (a) is hindered, the absorption of water in the soil is reduced, and the soil for the anti-adhesion paint is used. It is not preferable because the adhesion preventing function is reduced. On the other hand, if the hydrophilicity of the hydrophilic binder resin (b) is too high, the adhesive strength of the binder to the substrate when absorbing soil moisture is too low, and the whole coating film is undesirably peeled off too quickly. For the reasons described above, the hydrophilic binder resin (b) preferably has an appropriate hydrophilicity.

The acid value of the hydrophilic binder resin (b) of the present invention is 40 mgKOH /
g or more, more preferably 50 mgKOH / g or more, and even more preferably 70 mgKOH / g or more. When the acid value of the hydrophilic binder resin (b) is less than 40 mgKOH / g, the hydrophilicity becomes too low, which is not preferable. Further, in order to maintain the binder function at the time of water absorption, it is preferably at most 500 mgKOH / g, more preferably at most 300 mgKOH / g, even more preferably at most 200 mgKOH / g. When the acid value of the hydrophilic binder resin (b) exceeds 500 mgKOH / g, the hydrophilicity becomes too high, which is not preferable.

Next, the glass transition temperature of the hydrophilic binder resin (b) is not particularly limited, but the adhesion to the substrate, the workability when embedding the substrate in the soil, the soil adhesion inhibitor, -20 ° C to 1
It is preferred to have a glass transition temperature at 20 ° C. When the glass transition temperature is −20 ° C. or lower, the paint film for the soil adhesion inhibitor tends to be sticky, and there is a possibility that blocking may occur particularly when the base materials after application are left standing after being stacked. In addition, because the strength of the paint for soil adhesion inhibitor is insufficient,
It is not preferable because the base material is easily peeled off when buried in the soil. From this, it is more preferable that the glass transition temperature is 0 ° C. or higher.

When the glass transition temperature of the hydrophilic binder resin (b) is 120 ° C. or more, the anti-adhesive layer becomes too hard, and the adhesion to the substrate and the flexibility of the coating film for the anti-adhesion agent become poor. It is also unfavorable because, when the base material is buried in the soil, peeling and falling off of the water-absorbent resin (a) easily occur. For this reason, the glass transition temperature is more preferably 100 ° C. or lower, and more preferably between 0 ° C. and 20 ° C. and between 20 ° C. and 10 ° C.
It is more preferable that the glass transition temperature is between 0 ° C. because the balance between the softening component and the shape maintaining component is good.

The weight average molecular weight (Mw) of the hydrophilic binder resin (b) is not particularly limited, but may be 30,000.
The range of 0 to 300,000 is preferable, and 50,000 to
A range of 200,000 is more preferred. By using the resin having the above-mentioned weight average molecular weight, it becomes easy to balance the toughness of the anti-adhesion material with the solubility in alkaline water.

As the hydrophilic binder resin (b), the hydrophilicity can be easily adjusted by adjusting the acid value or the like.
It is preferable to use an OH / g resin.

Hereinafter, the alkali water-soluble resin of the present invention will be described. The alkali water-soluble resin, which is one kind of the hydrophilic binder resin (b) constituting the paint for soil adhesion inhibitor of the present invention, is dissolved in a 0.4% by weight aqueous solution of NaOH, and is dissolved in neutral or acidic water. Is an insoluble resin. The alkali water-soluble resin is not particularly limited as long as it has the solubility specified above. For example, α, β-
A copolymer of an unsaturated carboxylic acid monomer and another monomer copolymerizable therewith can be exemplified.

The solubility in the above-mentioned alkaline water is not particularly limited, but the preferable solubility of the alkaline water-soluble resin as a binder resin which can be preferably used in the present invention will be described later. . In addition, the term “alkali water-soluble resin” of the present invention may be expressed as an alkali-soluble resin in another expression. Since it is more clear to use an alkali water-soluble resin,
In the present invention, an alkali water-soluble resin is used.

The solubility of the alkali water-soluble resin which can be preferably used in the present invention in alkaline water is not particularly limited as long as the characteristics of the present invention are not impaired.

For example, it can be defined by the weight reduction rate of the alkali water-soluble resin in the following solubility test. The solubility of the alkali water-soluble resin which can be preferably used in the present invention in alkaline water is, for example, a molded product of 5 mm or less of the alkali water-soluble resin (for example, a 3 mm pellet shape as in Examples, Even if it is not pelletized, it may be cut or the like so as to have a size of 5 mm square or less.) 10 g is put into 500 g of a 0.4% by weight aqueous solution of NaOH,
It can be determined by the reduction rate of the weight of the alkali water-soluble resin molded article dissolved in the alkaline water after stirring for a time.

That is, if there is any resin remaining without being dissolved after stirring for 24 hours, the resin is filtered, washed with water, and the weight after drying is determined. Before being subjected to the solubility test, it can be determined by a reduction rate from the weight of the original alkali water-soluble resin. That is, <original weight−weight after solubility test> / <
Original weight> can be determined in terms of%.

The alkaline water-soluble resin of the present invention includes
This value is preferably between 50% and 100%. More preferably, it is 60-100%. More preferably, it is 70-100% by weight.

The method for producing the alkaline water-soluble resin and the hydrophilic binder resin having an acid value of 40 to 500 mgKOH / g of the present invention is not particularly limited, but the following α, β-unsaturated carboxylic acid monomer and A copolymer obtainable by polymerization using an unsaturated monomer component comprising a monomer other than the polymerizable α, β-unsaturated carboxylic acid monomer is preferable.

For example, the α, β-unsaturated carboxylic acid monomer used in the production of the alkaline water-soluble resin of the present invention and the hydrophilic binder resin having an acid value of 40 to 500 mg KOH / g includes, for example, acrylic acid Α, β-unsaturated carboxylic acids such as methacrylic acid, maleic acid, itaconic acid and fumaric acid; α, β-unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride; maleic acid monoester, fumaric acid Monoesters of α, β-unsaturated dicarboxylic acids such as monoesters and itaconic acid monoesters can be mentioned. The α, β-unsaturated carboxylic acid monomer may be only one kind or two or more kinds.
Of these, acrylic acid and / or methacrylic acid, which are acrylic α, β-unsaturated carboxylic acids, are preferably used because they are inexpensive and have good copolymerizability with other unsaturated monomers.

Next, other monomers that can be copolymerized with the α, β-unsaturated carboxylic acid monomer include, for example, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, stearyl acrylate, methyl methacrylate, ethyl methacrylate Esters of monohydric alcohols having 1 to 18 carbon atoms with (meth) acrylic acid, such as methacrylate, propyl methacrylate, butyl methacrylate, and stearyl methacrylate; acrylonitrile;
Nitrile group-containing vinyl monomers such as methacrylonitrile; amide group-containing vinyl monomers such as acrylamide and methacrylamide; hydroxyl-containing vinyl monomers such as hydroxyethyl acrylate and hydroxypropyl methacrylate; glycidyl methacrylate and the like Epoxy group-containing vinyl monomers; metal salts of α, β-unsaturated carboxylic acids such as zinc acrylate and zinc methacrylate; styrene, α
-Aromatic vinyl monomers such as methylstyrene; aliphatic vinyl monomers such as vinyl acetate; halogen-containing vinyl monomers such as vinyl chloride, vinyl bromide, vinyl iodide, and vinylidene chloride; allyl ether Maleic acid derivatives such as dialkyl esters of maleic acid; fumaric acid derivatives such as dialkyl esters of fumaric acid; maleimide derivatives such as maleimide, N-methylmaleimide, stearylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide; itaconic acid Mono- and dialkyl esters, itaconic amides, itaconic imides, itaconic amide esters and other itaconic acid derivatives; alkenes such as ethylene and propylene; dienes such as butadiene and isoprene; vinyl ethers; 2- (meth) acryloylpropane Sulfone (Salt), 3-allyloxy-2
Examples thereof include unsaturated monomers having a sulfonic acid (salt) group such as hydroxypropanesulfonic acid (salt), polyalkylene glycol (meth) acrylates, and the like, and one or more of these are used. be able to.

Among these, as the alkyl (meth) acrylate, esters having various properties can be easily obtained, and by appropriately combining them, the Tg (hardness, softness) of the binder resin can be obtained. It is preferable because the adhesion to the substrate can be easily adjusted and the copolymerizability with the α, β-unsaturated carboxylic acid monomer is relatively good.

The above (meth) acrylic acid alkyl ester is used in an amount of from 30% by weight to 1% by weight based on 100% by weight of the total amount of other monomers copolymerizable with the α, β-unsaturated carboxylic acid monomer.
It is preferably used at 00% by weight, more preferably at least 50% by weight to 100% by weight. More preferably 60 to 100% by weight, further preferably 70 to 100% by weight.
100% by weight. That is, the use of an acrylic monomer as another monomer is a preferred embodiment as a form of the alkali water-soluble resin as the hydrophilic binder resin (b) of the present invention.

The ratio of the above α, β-unsaturated carboxylic acid monomer and the unsaturated monomer component composed of another monomer copolymerizable therewith is not particularly limited.
When the unsaturated monomer component comprising an unsaturated carboxylic acid monomer and another monomer copolymerizable therewith is defined as 100% by weight, α, β-unsaturated carboxylic acid in all monomer components is The proportion is preferably 7 to 80% by weight based on the total amount of the unsaturated monomer. More preferably, it is 7 to 50% by weight. More preferably, it is 9 to 30% by weight.

The proportion of the α, β-unsaturated carboxylic acid monomer in all the monomers in the alkali water-soluble resin is 7% by weight.
When it is less than 3, hydrophilicity tends to be too low due to low acid value. When the ratio exceeds 80% by weight,
Problems tend to occur when the hydrophilicity is too high.

Use as a raw material for producing a hydrophilic binder resin having an acid value of 40 mgKOH / g or more and 500 mgKOH / g or less, that is, a binder resin obtained by polymerizing the above-mentioned unsaturated monomer component of the present invention. Α
The amount of the copolymerizable monomer other than the β-unsaturated carboxylic acid monomer may be the above α, β-unsaturated carboxylic acid monomer and another monomer (g) copolymerizable therewith. 100% by weight, preferably 93 to 20% by weight of the total amount of unsaturated monomers. More preferably 93-
50% by weight. More preferably, it is 91 to 70% by weight. When the ratio of the α, β-unsaturated carboxylic acid monomer is less than 20%, the hydrophilicity is lowered, and 93%
If it exceeds, the hydrophilicity becomes too high, which is not preferable.

The method for producing the alkali water-soluble resin of the present invention is as follows:
There is no particular limitation, and generally known polymerization methods such as solution polymerization, bulk polymerization, emulsion polymerization, and suspension polymerization can be used. Among them, production by solution polymerization in an organic solvent is preferable.

This is because the water-absorbing resin is mixed with the solution or dispersion containing the alkali water-soluble resin obtained by the solution polymerization as it is, thereby making it possible to produce the paint for soil adhesion inhibitor of the present invention. Because.

As the polymerization form, radical polymerization,
Examples thereof include anionic polymerization, cationic polymerization, and coordination polymerization, and radical polymerization is preferable as an industrial production method.

Examples of the reaction vessel used for producing the raw material polymer include a tank reactor, a kneader, and a tubular reactor such as a static mixer. These reactors can be used together if necessary. A dropping tank is also used as needed. The pressure in the reaction vessel may be any of reduced pressure, normal pressure, and pressurized.

Next, the radical polymerization initiator used in the radical polymerization is not particularly limited, but specific examples thereof include 2,2′-azobisisobutyronitrile,
Examples include azo initiators such as 2,2'-azobis (2,4-dimethylvaleronitrile); and peroxide initiators such as benzoyl peroxide and di-t-butyl peroxide. These radical polymerization initiators are 2
More than one type may be used in combination.

The solvent used in the solution polymerization is not particularly limited as long as it does not hinder the radical polymerization reaction.
For example, alcohols such as methanol, ethanol and isopropyl alcohol; aromatic hydrocarbons such as benzene and toluene; ketones such as acetone and methyl ethyl ketone; aliphatic esters such as ethyl acetate and butyl acetate;
Examples thereof include ethylene glycol derivatives such as ethylene glycol and ethylene glycol monomethyl ether, and propylene glycol derivatives such as propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate. Two or more of these solvents may be used in combination.

Next, the solvent (c) used in the present invention will be described. The solvent (c) can be used without particular limitation as long as it is a known solvent used for ordinary paints and the like. For example, one or more of the solvents exemplified in the description of the method for producing the alkali water-soluble resin or the like can be used. It can be used in combination of two or more.

As a method for selecting the solvent (c), it is preferable to select a solvent having a boiling point, safety and the like suitable for application to a substrate. If a solvent having a low boiling point is selected, it has a quick drying property, and a coating film can be formed in a short time, so that a thick coating or the like can be easily performed. If a solvent having a high boiling point is selected, the working time can be lengthened. By using an organic solvent as a medium, there is no swelling due to water absorption of the water-absorbent resin that occurs when a medium containing water is used, and the coating operation is facilitated because the resin does not become a gel. In addition, when a highly volatile solvent such as methyl ethyl ketone or methanol is used, it is dried in about 10 minutes, and since it dries much faster than when water is used as a medium, it is possible to quickly shift to the next operation or process. The work period or the time required for application to the substrate can be significantly reduced.

The paint for soil adhesion inhibitor of the present invention has the characteristics as long as it contains the water-absorbent resin (a), the hydrophilic binder resin (b) and the solvent (c) described above as essential components. As long as it does not hinder, other additives (h) may include other resins, pigments, various stabilizers, various fillers, and the like.

The ratio of the water-absorbent resin (a), hydrophilic binder (b) and solvent (c) to other additives (h) is not particularly limited, but the features of the paint for soil adhesion inhibitor of the present invention are regretted. Water-absorbent resin (a)
Weight ratio ([(a) + (b) + (c)]) of the total of the combination of the hydrophilic binder (b) and the solvent (c)
/ [(A) + (b) + (c) + (h)] × 100
(%)) Is preferably 50% or more, more preferably 70% or more, and most preferably 80% or more.

The ratio of the water-absorbent resin (a), hydrophilic binder (b), solvent (c) and other additives (h) is not particularly limited. In order to demonstrate the regret, the water-absorbent resin (a)
Is 5 to 60% by weight, and the hydrophilic binder (b) is 10 to 7%.
0% by weight, 5 to 70% by weight of solvent (c), 0 to 50% by weight of other additives (h), 10 to 50% by weight of water-absorbent resin (a), hydrophilic binder (b) Is more preferably 10 to 60% by weight, the solvent (c) is 10 to 60% by weight, and the other additive (h) is more preferably 0 to 30% by weight.

The method of applying the paint for soil adhesion inhibitor of the present invention to various substrates is not particularly limited as long as it is a known method of applying a paint. For example, a brush, a roller or the like may be used. Alternatively, spray painting may be performed using a spray device such as ricin gun.

The coating thickness of the paint for soil adhesion inhibitor of the present invention on various substrates is not particularly limited.
m is preferable, and 100-1000 micrometers is more preferable.

Further, the paint for an soil adhesion inhibitor of the present invention is
When the amount of water in the soil is small and when the burial period of the temporary steel material coated with the soil adhesion preventive paint is short, the thickness of the soil adhesion preventive paint applied to various base materials can be reduced. With a very small amount of water absorption, the paint film for the soil adhesion inhibitor swells, and the adhesion to the temporary steel material can be reduced.

When the moisture content in the soil is large and when the temporary steel material coated with the soil adhesion inhibitor paint is buried for a long time, the thickness of application of the soil adhesion inhibitor paint to various substrates is increased. By doing so, even if a relatively large amount of water is absorbed, the paint film for the soil adhesion preventing agent can be stabilized on the surface of the temporary steel material during the embedding period, and soil adhesion to the temporary steel material can be prevented.

The paint for soil adhesion inhibitor of the present invention can be prepared by adjusting the coating thickness of the temporary steel material, for example, as described above, and by controlling the ratio of the water-absorbent resin (a) to the hydrophilic binder resin (b). By adjusting the hydrophilicity of the hydrophilic binder, the ability to prevent soil adhesion can be exhibited in accordance with the soil properties at various sites and the burial period.

The base material to which the present invention is applied is not particularly limited as long as it is a known base material used as a temporary steel material on the premise of drawing and collecting for forming a retaining wall and the like. Sheet pile), corrugated sheet, H-section steel,
Examples include piles such as I-section steel, steel pipe piles, iron columns, and the like.

The paint for soil adhesion inhibitor of the present invention has a ratio (X) between the adhesion (X) of the paint film for soil adhesion inhibitor to steel and the breaking strength (Y) of the paint film for soil adhesion inhibitor. / Y) is 0.5
It is preferable that it is above.

The paint for an anti-adhesion agent of the present invention is applied to a temporary steel material, for example, a steel sheet pile to be recovered, and when the steel sheet pile is driven into the ground, the film on the surface of the steel sheet pile becomes soil. Or it receives a large frictional force due to friction with buried objects (stones, rubble, etc.) in the soil. Furthermore, the friction is not constant, and some parts receive a particularly large frictional force locally, but at this time, if the coating film is peeled off from the base material in a large area, the peeled part may be damaged. The soil adhesion prevention function is extremely reduced.

For this reason, the paint film for the soil adhesion inhibitor of the present invention has a large adhesive force (during drying) with a temporary steel material (mainly steel sheet pile) on which recovery is premised, and when a part of the paint film is peeled off. In addition, it is necessary that the film breaking strength is weak so that the periphery does not follow.

In view of the above conditions, the paint for soil adhesion inhibitor of the present invention has an adhesive force (X) with a temporary steel material (mainly steel sheet pile) on which the paint film is to be recovered, and the paint film. The ratio ((X) / (Y)) of the breaking strength (Y) is preferably 0.5 or more, more preferably 0.7 or more,
Most preferably, it is 1.0 or more.

When the above (X) / (Y) is less than 0.5, the soil adhesion preventive paint film is compared with the adhesion (X) of the paint film to the temporary steel material (mainly steel sheet pile) to obtain the soil. Since the breaking strength (Y) of the paint film for anti-adhesive agent is large, once the peeling of the paint film occurs, the peeling propagates through the paint film for anti-adhesive agent, and the large area easily peels off. Therefore, the performance of preventing soil adhesion after peeling is remarkably reduced, and a problem is likely to occur.

The magnitude of the adhesion (X) when drying the paint film for the soil adhesion inhibitor is not particularly limited. However, if the adhesion (X) during drying is too small, the impact of the temporary steel material on Adhesion (X) because peeling easily occurs during installation
Is preferably 100 N / cm ² or more, and 30
More preferably, it is 0 N / cm ² .

Further, after the temporary steel material is buried, the coating film swells due to the absorption of moisture in the soil, and the adhesion to the temporary steel material is reduced. Then, the paint film for the soil adhesion inhibitor after swelling is separated from the temporary steel material by the frictional force with the surrounding soil at the time of pulling, so that the temporary steel material can be collected almost purely. for that reason,
The adhesion between the swelled paint film for soil adhesion inhibitor and the temporary steel material that has sufficiently absorbed water is preferably 10 N / cm ² or less, more preferably 5 N / cm ² or less.
Most preferably, it is 1 N / cm ² or less.

[0069]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. The acid value of the hydrophilic binder resin (b) is J
It was measured based on the test method described in the application clause 4.3 of IS K6901 “Test method for liquid unsaturated polyester resin”. However, when the hydrophilic binder resin (b) did not dissolve in the solvent specified in the test method, the measurement was carried out in accordance with the above test method, using a suitable solvent to dissolve the hydrophilic binder resin. The glass transition temperature of the hydrophilic binder resin (b) was measured in accordance with "JIS K 7121 Plastic transition temperature measurement method" under a nitrogen atmosphere using DSC220C manufactured by Seiko Instruments Inc. In addition, the condition adjustment of the test specimen was performed according to 3. According to (3).

The solubility test of the alkali water-soluble resin of the present invention was performed by using the solubility of alkaline water-soluble resin of the present invention in alkaline water and the weight loss rate as described below. For example, a molded product of 5 mm or less of an alkali water-soluble resin (for example, a pellet shape of 3 mm as in the examples, but even if it is not pelletized, cut into a size of 5 mm or less, for example) Do it.) 10
was added to 500 g of a 0.4% by weight aqueous solution of NaOH, and the mixture was stirred at 25 ° C. for 24 hours. .

That is, if any resin remains without being dissolved after stirring for 24 hours, the resin is filtered, washed with water, and the weight after drying is determined. Before being subjected to the solubility test, it can be determined by a reduction rate from the weight of the original alkali water-soluble resin. That is, <original weight−weight after solubility test> / <
Original weight> can be determined in terms of%. Also,
If no resin component remaining without being dissolved by filtration was observed, it was regarded as dissolved.

The method for measuring the adhesion (X) of the paint film for soil adhesion inhibitor of the present invention to a temporary steel material is as follows.

The paint for soil adhesion inhibitor of the present invention is applied in advance to a base material of the same material as the temporary steel material of 50 mm × 50 mm to a desired film thickness and dried.

Next, a jig made of steel as shown in FIG.
Using an adhesive (for example, an epoxy-based adhesive (for example, Araldite (manufactured by Ciba Geigy), etc.)), the lower surface of the steel material (the surface on which the paint for applying the soil adhesion inhibitor is not applied) and the upper surface of the steel material (the surface on which the paint for the soil adhesion inhibitor is applied, 1 on paint film for soil adhesion inhibitor)
A total of two pieces are adhered to each other, and cured and cured for a curing time specified for the adhesive.

Using a commercially available tensile tester, the substrate /
The adhesion strength (peeling force) between the paint films for the soil adhesion inhibitor is measured (25 ° C., pulling speed: 10 mm / min).

The number n is set to 3 to 5, and the average value of all the data is defined as the adhesion strength (X) except for the data of the sample peeled except between the base material and the paint film for the soil adhesion inhibitor.

Further, after the adhesion of the paint film for soil adhesion inhibitor to the temporary steel material in the wet state is completed, the coated and dried base material is immersed in ion-exchanged water at 25 ° C. for 72 hours.
It measures by performing the following operations.

The method of measuring the breaking strength (Y) of the paint film for the soil adhesion inhibitor is as follows. The breaking strength (Y) of the paint film for soil adhesion inhibitor was determined by punching the paint film for soil adhesion inhibitor into a No. 3 dumbbell in accordance with JIS K6301, and pulling it at 25 ° C using a commercially available tensile tester. Speed: Measured under the condition of 50 mm / min. n is 3
５5 pieces, and the average value of all the data (breaking strength) is defined as the breaking strength (Y).

[Production Example 1] A water-absorbing resin was prepared by the following method. That is, a kneader equipped with a table-top jacket having a capacity of 1.5 L and provided with a thermometer and a blade (stirring blade), the inner surface of which is lined with ethylene trifluoride, was used as a reactor, and methoxypolyethylene glycol methacrylate was used as the reactor. (Molecular weight 512) 60.18 g, methacrylic acid (Molecular weight 86.09) 3.76 g, Sodium methacrylate (Molecular weight 108) 210.69 g, Polyethylene glycol diacrylate 1.3 as a crosslinking agent
g, and 352.37 g of ion-exchanged water as a solvent were charged. The proportion of the crosslinking agent in the monomer component is 0.14
Mol%.

By flowing hot water of 50 ° C. through the jacket, the above aqueous solution is stirred under a stream of nitrogen gas for 50 hours.
Heated to ° C. Next, 2,2′-azobis- (2-amidinopropane) dihydrochloride (molecular weight 2
71.27, Chemical product V-50 manufactured by Wako Pure Chemical Industries, Ltd.)
Was added and stirred for 10 seconds, then the stirring was stopped and the mixture was allowed to stand. The ratio of the polymerization initiator to the monomer component is 0.2 mol%.

The polymerization reaction was started immediately after the addition of the polymerization initiator, and the internal temperature reached 100 ° C. (peak temperature) after 90 minutes. Thereafter, the contents were aged for 30 minutes while flowing warm water of 80 ° C. through the jacket. Thus, a hydrogel was obtained. After completion of the reaction, the hydrogel was disintegrated by rotating a blade until the hydrogel became fine, and then the hydrogel was taken out by inverting the reactor.

The obtained hydrogel was dried at 140 ° C. for 3 hours using a hot air circulation type drier. After drying, the dried product was pulverized using a desktop simple pulverizer (manufactured by Kyoritsu Riko Co., Ltd.). Thus, a water-absorbent resin (1) having an average particle diameter of 160 μm was obtained.

[Production Example 2] Hydrophilic binder resin (b)
Was prepared by the following method.

That is, a capacity 5 having a thermometer and a dropping device
0.45 kg of acrylic acid, 2.3 kg of ethyl acrylate, 0.25 k of methyl methacrylate
g, 2,2′-azobis- (2,4-
12 g of dimethylvaleronitrile) and 3 kg of methyl alcohol as a solvent were charged. In addition, 1.05 kg of acrylic acid and 2.2 parts of methyl acrylate were added to the dropping device.
kg, 3.75 kg of methyl methacrylate, 26 g of 2,2′-azobis- (2,4-dimethylvaleronitrile),
And a mixed solution consisting of 7 kg of methyl alcohol was charged.

The above methyl alcohol solution was heated to 65 ° C. with stirring in a nitrogen gas atmosphere, and reacted for 20 minutes. Thereby, the polymerization rate of the content was adjusted to 72%. Subsequently, while maintaining the internal temperature at 65 ° C., the above mixed solution was dropped uniformly from the dropping device over 2 hours. After completion of the dropwise addition, the content was aged at 65 ° C. for another 3 hours. After completion of the reaction, 33 kg by weight of the hydrophilic binder resin (1) is mixed by mixing 10 kg of methyl alcohol with the content.
A methyl alcohol solution was obtained.

The weight average molecular weight of the obtained hydrophilic binder resin (1) is 120,000, and the acid value is 115 mg KOH.
/ G. As a result of performing differential scanning calorimetry on the hydrophilic binder resin (1), the hydrophilic binder resin (1) had two glass transition temperatures in the range of -80 ° C to 120 ° C. Further, the obtained methyl alcohol solution of the hydrophilic binder resin 1 was desolvated using a twin-screw extruder to obtain a cylindrical pellet having a diameter of 3 mm and a length of 3 mm. 10 g of the pellet was charged at room temperature into 500 g of a 0.4% by weight aqueous solution of sodium hydroxide in a beaker, and the mixture was stirred with a magnetic stirrer and completely dissolved after 4 hours.

Example 1 50 parts by weight of the water-absorbent resin produced in Production Example 1 and 150 parts by weight of a 33% by weight methyl alcohol solution of the hydrophilic binder resin (1) produced in Production Example 2 were mixed and dispersed. By doing so, a paint (1) for an soil adhesion inhibitor according to the present invention was obtained. Then, the obtained paint for soil adhesion inhibitor (1) is uniformly spread on the lower 7.5 m (both front and back) of an IV-type steel sheet pile having a length of 8.1 m so as to have a dry thickness of 200 μm. By applying and drying, a steel sheet pile (1) for preventing soil adhesion of the present invention was obtained. After 1 hour of natural drying, the coating film had sufficient strength, and was not easily peeled off even when strongly rubbed with an iron spatula.

The thus obtained steel sheet pile (1) for preventing soil adhesion according to the present invention is buried in the soil of Shinagawa-ku, Tokyo (silt layer) using a vibro. Draw out was carried out.

Table 1 shows the adhesion of the soil and the soil-preventing agent paint (1) to the soil sheet-preventing steel sheet pile (1) after the drawing.
FIG. 2 (first from left: convex surface, second from left: concave surface) is shown in FIG.

As can be seen from Table 1 and FIG. 2, almost no adhesion of the soil and the paint for the soil adhesion inhibitor (1) was observed, and the soil adhesion prevention ability was very good. Understand.

Example 2 The same operation as in Example 1 was carried out except that a steel sheet pile for soil adhesion prevention (2) obtained by setting the coating thickness of the paint for soil adhesion inhibitor (1) to 400 μm was used. Table 1 shows the adhesion state of the soil and the soil adhesion inhibitor paint (1) and the paint film on the soil sheet pile (2) for soil adhesion prevention after drawing.
FIG. 2 (third from the left: convex surface, fourth from the left: concave surface) is shown in FIG.

As can be seen from Table 1 and FIG. 2, except that a part of the coating film remained on the upper part and a small amount of soil was partially adhered on the lower part, paint for the soil and the soil adhesion preventive agent ( 1) No adhesion of the coating film was observed, indicating that the ability to prevent soil adhesion was good.

Comparative Example 1 The same operation as in Example 1 was carried out except that a comparative steel sheet pile (1) to which the paint (1) for soil adhesion inhibitor was not applied was used. Table 1 summarizes the adhesion of soil to the steel sheet pile (1) for use, and the photograph at that time is shown in FIG. As can be seen from Table 1 and FIG. 3, the comparative steel sheet pile (1) after the drawing showed a large amount of soil adhesion everywhere, indicating that there was no soil adhesion prevention ability at all.

[0094]

[Table 1]

[0095]

According to the present invention, the paint for an anti-fouling agent containing the water-absorbent resin (a), the hydrophilic binder resin (b) and the solvent (c) as essential components can be easily used for temporary steel buried underground. When the temporary steel is driven into the ground, it hardly peels off from the base material. The temporary steel after drawing has almost no soil adhesion and the void after drawing the temporary steel is minimized (substantially the same as the volume of the temporary steel itself), which is necessary for post-processing (backfilling). The use of chemicals and earth and sand is minimized.

[Brief description of the drawings]

FIG. 1 is a schematic view of a jig for a tensile test used when measuring the adhesion (X) of a water stopping agent of the present invention to a substrate.

FIG. 2 is a photograph of steel sheet piles (1) and (2) for soil adhesion inhibitor after drawing in Examples 1 and 2.

FIG. 3 is a photograph of a comparative steel sheet pile (1) after drawing in Comparative Example 1.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-321421 (JP, A) JP-A-63-27619 (JP, A) JP-A-58-191816 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C09D 201/00-201/10 C09D 5/00 E02D 5/04 E02D 9/02 C09K 3/00

Claims (6)

(57) [Claims] 1. A water-absorbent resin (a), a hydrophilic binder resin
Soil adhesion inhibitor containing (b) and solvent (c) as essential components
Paint, wherein the hydrophilic binder resin (b) is
Soil adhesion inhibitor characterized by being a potassium water-soluble resin
Paints. 2. A water-absorbent resin (a), a hydrophilic binder resin
Soil adhesion inhibitor containing (b) and solvent (c) as essential components
Acid value of the hydrophilic binder resin (b).
Is 40 to 500 mgKOH / g.
Paint for soil adhesion inhibitor. 3. The water-absorbent resin (a) is a salt-resistant water-absorbent resin.
3. Prevention of soil adhesion according to claim 1 or 2,
Agent paint. 4. The soil attachment according to claim 1, wherein
Soil adhesion prevention work characterized by using paint for inhibitor
Law. 5. A soil attachment according to claim 1, wherein
Soiling, characterized in that the paint for the inhibitor has been applied in advance
Steel sheet pile for anti-wear. 6. A steel sheet pile for preventing soil adhesion according to claim 5.
Soil adhesion prevention method characterized by that.