JP2000265468A - Adhesion preventive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly improve separating work of a support and a hardened body of a hydraulic setting composition by interposting a water absorptive material and a binder for sticking this between the hydraulic setting composition and the support. SOLUTION: A hole is excavated in the ground 1 so that a support 3 is loosely inserted. Next, a hydraulic setting composition is placed around the support 3 to be hydrated to form a hardened body 2 of the hydraulic setting composition. Or the support 3 is embedded in the hydraulic setting composition placed in an excavating hole to be hardened to form the hardened body 2. Before this execution work, an adhesion preventive material 4 is uniformly applied to a surface of the support 3. Then, an alkaline water soluble resin 4b of the adhesion preventive material 4 dissolves when contacting with alkaline water of the hydraulic setting composition. While, a water absorptive resin particle 4a of the adhesion preventive material 4 swells by absorbing the alkaline water. In that case, maximum pull-out strength of the adhesion preventive material 4 is set not more than 0.019 kgf/cm2 to thereby reduce labor pulling out the support to improve workability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive which is interposed between a hydraulic composition such as cement and a support such as steel to reduce the adhesive force between a cured product of the hydraulic composition and the support. It is about prevention materials. The anti-adhesion material is mainly used by coating, sticking or wrapping on the surface of the support.

[0002]

2. Description of the Related Art Generally, when a ground foundation structure as a structure such as an earth retaining wall is constructed in foundation work in the fields of construction and civil engineering, for example, an H-section steel is loosely inserted into a drilling hole. A hydraulic composition such as cement milk or ready-mixed concrete is injected around the H-shaped steel to be hardened, or, for example, an H-shaped steel is embedded as a core material in the hydraulic composition injected into the excavation hole ( After that, the hydraulic composition is cured. After the hardening of the hydraulic composition is completed, it is desired that the H-shaped steel be withdrawn from the hardened body and removed so as not to hinder the development of the underground later in the year. Also, at the actual construction site, after the hardening of the hydraulic composition is completed and its role as a retaining wall ends, due to the circumstances of the site and the convenience of construction, the H-section steel must be pulled out from the hardened body and removed. Often it must be done.

However, the H-section steel and the hardened body of the hydraulic composition are firmly adhered to each other, and in order to remove the H-section steel after the completion of the construction, the work of pulling out the H-section steel from the hardened body includes: A considerable amount of labor (tensile force) is required to overcome the adhesive strength, so the equipment for pulling out is expensive,
It takes days etc. In addition, the workability and safety of the workers are inferior, and if the drawn H-shaped steel can be recycled, it is beneficial to save resources as well, but the H-shaped steel is deformed due to the large tensile force and cannot be recycled. Was.

Therefore, in order to facilitate the above-mentioned drawing operation, conventionally, i) a method of previously applying a lubricating oil such as wax or grease to the surface of the H-section steel, a method of applying a water-absorbing resin to the surface of the H-section steel, By using an adhesive, or i
i) A method of attaching a lubricant to the surface of an H-section steel, and
ii) Various methods such as a method of coating an H-shaped steel with a coating material have been proposed.

[0005] As the method of the above i), for example,
Japanese Unexamined Patent Publication (Kokai) No. -58715 proposes to use an anti-adhesive material for pulling out a core material, which comprises a water-absorbing resin and a spreading agent such as a polyester resin, a vinyl resin, an acrylic resin, and a urethane resin. .

Further, for example, Japanese Patent Application Laid-Open No. 63-165615
Japanese Patent Application Laid-Open No. H11-216, proposes a method of reducing frictional resistance when pulling out a steel material by using a water-swellable film composed of a water-absorbent resin and a volatile film-forming resin such as natural rubber, synthetic rubber, and plastic. ing.

[0007] As the method ii), for example, Japanese Patent Application Laid-Open No. 6-185054 proposes that a sheet-like lubricant made of superabsorbent fibers be adhered to the surface of a steel material. Further, for example, Japanese Patent Application Laid-Open No. Sho 62-174418
Japanese Patent Laid-Open Publication No. HEI 9-214605 proposes a method of reducing the frictional resistance when pulling out a steel material by using a lubricating tape composed of a water-absorbing resin and a binder.

As the method iii), for example, JP-A-7-247549 discloses a polymer sheet obtained by directly fixing a water-absorbing resin to a base material such as a nonwoven fabric without using a bonding agent. A method has been proposed in which a temporary buried object is covered with a bag-shaped lubricant to reduce the frictional resistance when the temporary buried object is pulled out.

[0009]

However, the spreading agent contained in the anti-adhesion material described in JP-A-64-58715 and the water-swellable film described in JP-A-63-165615 are used. The volatile film-forming resin contained therein has poor solubility or swelling in water exhibiting alkalinity (hereinafter referred to as cement water) contained in the hydraulic composition. Therefore, the spreading agent and the volatile film-forming resin hinder volume expansion when the water-absorbing resin absorbs water and swells. The above-mentioned conventional anti-adhesive material and water-swellable film, the spreading agent and the volatile film-forming resin cover the surface of the water-absorbent resin and hinder the volume expansion of the water-absorbent resin. Water-soluble resin cannot sufficiently exhibit its water-absorbing properties (performance). Further, the water-absorbing resin contained in the conventional anti-adhesion material and the water-swellable film has poor swellability with respect to cement water. In addition, a coating film formed by applying an anti-adhesion material to a core material (temporary buried material) such as an H-section steel and a water-swellable film are inferior in flexibility and toughness. It is easy to peel off or sticky from the core material due to temperature change. Further, when applying an anti-adhesion material at a work site, there is a disadvantage that it is necessary to secure labor, time, place, and the like for heating, melting, and applying the anti-adhesion material.

The lubricant described in Japanese Patent Application Laid-Open No. 6-185054 and the lubricating tape described in Japanese Patent Application Laid-Open No. Sho 62-174418 are capable of absorbing and swelling super-absorbent fibers and water-absorbent resins with respect to cement water. Therefore, the improvement of the pulling operation of the pile (steel material) is insufficient. And
Since the above-mentioned lubricating tape dissolves easily when the binder comes into contact with water, the water-absorbing resin easily falls off.
In addition, since the surface of the pile (steel material) is usually rusted or stained, it is difficult to apply the lubricating tape. In addition, it may come in contact with cement water at the time of construction, or may be unexpectedly wetted by rain or rain. The water-absorbent resin is easy to fall off. Therefore, the lubricating tape cannot exert its effect. In addition, the pile (steel) can be slippery due to the melted binder, which can be dangerous. If piles (steel) are piled up in piles, when the pile (steel) gets wet due to rainfall, etc., lubricating tape should be used. There are many restrictions on construction, such as being unable to attach. On the other hand, since the above-mentioned lubricating material is a sheet made of superabsorbent fibers, it absorbs water more easily than the above-mentioned lubricating tape. For this reason, the lubricating material is easy to fall off, and since the surface of the pile (steel material) usually has rust or dirt attached thereto, it is difficult for the lubricating material to stick, and therefore the same problem as described above is caused. Will be done. Further, the above-mentioned conventional anti-adhesion material, water-swellable film, lubricating material and lubricating tape are directly fixed to a support such as H-section steel. Therefore, these anti-adhesives can only come into contact with cement water on one side (front side) only, so that the water-absorbent resin or super-absorbent fiber can exhibit its water-absorbing properties (performance) sufficiently. Therefore, it is difficult to pull out the core material from the cured product of the hydraulic composition. Therefore, the conventional anti-adhesion material, water-swellable film, lubricating material, and lubricating tape have a problem that satisfactory performance cannot be obtained and the effect of facilitating the operation of pulling out a support such as an H-section steel is poor. Have.

In the bag-shaped lubricant described in Japanese Patent Application Laid-Open No. 7-247549, a water-absorbing resin is directly and firmly fixed to a base material without using a bonding agent. The lubricant includes:
Non-woven fabrics, which are thin and flexible, and have a low entanglement of fibers and a low binding force (weak fiber regulation), are preferably used. However, the strength (for example, tensile strength) of this lubricant is low because a substrate with a weak entanglement between fibers is used, so that the lubricant is not suitable for coating a temporary buried material (support) or for an injected hydraulic composition. This lubricant may be damaged by an external force applied when the temporary buried object is embedded (driven). For this reason, it may not be possible to prevent the temporary buried object from sticking to the cured body of the hydraulic composition. Further, when a base material having a large thickness and high strength is used, the productivity of a product (lubricating material) is extremely reduced. Therefore, there is a problem that the quality of a product (lubricating material) is deteriorated.

[0012] Therefore, a material such as an H-section steel, which can facilitate the work of pulling out the support, that is, the support can be removed without causing the above-mentioned various problems when constructing the support. There is a need for a material that can be more easily and reliably extracted from a cured product of a hard composition.
In addition, at present, pull-out properties and workability are insufficient, and there are problems such as the necessity of urgently bringing in a larger pull-out device than planned at the time of pull-out work, but there is no alternative technology. , A method of directly applying lubricating oil to the surface of a support such as an H-section steel, and a method of coating a support such as an H-section steel with a lubricated polyvinyl chloride sheet or the like. It is just that.

When a ground foundation such as a foundation is constructed in foundation work in the construction field, for example, a cylindrical hollow pile (pile) is added to cement milk cast in an excavation hole.
After that, the cement milk is hydrated and hardened. And the hydrate of the hydraulic composition such as a cement hardened body filled inside the pile is to install a reinforcing member for connecting a building such as a building.
The upper part (pile head) is dug up and cut to a predetermined depth using a drill or the like. However, the pile and the hydrate of the hydraulic composition such as the cement hydrate are firmly adhered, and the work of peeling the hardened cement from the pile includes:
Since considerable labor is required to overcome the adhesive strength, equipment, cost, and days are required. That is, since the workability is poor, the ground foundation structure cannot be quickly constructed.
Therefore, there is a need for an anti-adhesion material that can improve the workability of the operation of peeling the cured cement from the pile.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide, for example, an anti-adhesion material which reduces the adhesive force between a cured product of a hydraulic composition and a support. It is in. Another object of the present invention is to provide an anti-adhesion material for preventing the adhesive strength from increasing due to the drop of the water-absorbent resin or the damage.

The present invention relates to a cured product of a support and a hydraulic composition, such as an operation of pulling out a support such as an H-section steel, and a process of separating a cured product from a pile by removing a cured cement from a hollow pile. It is an object of the present invention to provide an anti-adhesion material that can speed up and improve the separation operation from the adhesive.

[0016]

Means for Solving the Problems The present inventors diligently studied an anti-adhesion material in order to solve the above-mentioned conventional problems. As a result, a water-absorbing material such as a water-absorbing resin is adhered to the surface of a support such as an H-beam by using a bonding agent (binder) by applying or pasting, or a sheet-like base having the water-absorbing material adhered by the bonding agent. By wrapping the support with a material, when the support is brought into contact with a hydraulic composition such as cement milk and cured, the adhesive strength between the cured body of the hydraulic composition and the support is significantly reduced. The inventors have found that the two can be easily separated, and have completed the present invention.

That is, in order to solve the above problems, the anti-adhesion material of the present invention comprises at least a water-absorbing material and a bonding agent for adhering the water-absorbing material, and is interposed between the hydraulic composition and the support. A material for reducing the adhesive strength between the cured body of the hydraulic composition and the support, and having a maximum pull-out strength of 0.019
kgf / cm ² or less.

According to the above configuration, the adhesive strength between the cured product of the hydraulic composition and the support can be suppressed.
Thereby, when pulling out the support from the cured product of the hydraulic composition, the labor (tensile force) in the pulling-out operation can be further reduced, so that the workability and safety of the worker are improved. Can be. On the other hand, when peeling the hydrate of the hydraulic composition from the embedded material, the labor can be reduced, and the workability of the operation of peeling the cured product of the hydraulic composition from the support can be improved. it can.

Therefore, according to the above configuration, it is possible to provide an anti-adhesion material which can be suitably used for preventing the hydraulic composition from adhering to the support.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION
It is determined by the following procedure and formula.

First, 100 mm high × 1 width, which is also published in construction prices (published monthly by the Japan Construction Price Survey Committee).
00mm x thickness 6mm x thickness 8mm (H-100mm x
An anti-adhesion material (sample) is applied to the surface of an H-section steel having a length of 1 m and a weight of 16.9 kg by applying, sticking, or wrapping it in its form. The H-shaped steel to be used is a new one having a smooth surface.

Next, soil cement milk (hydraulic composition) having a weight composition ratio of water / cement / clay / bentonite = 755/175/488/18 was injected so that the depth became 80 cm or more. The H-section was vertically embedded in the center of a cylindrical container with a bottom of 250 mm.

In addition, water uses ion-exchanged water, cement uses a blast furnace type B product, and clay uses Kasaoka clay.
Bentonite uses SA-B manufactured by Sanritsu.

Next, the 1-mH section steel is pulled out after the soil cement is hardened for 7 days and the maximum pulling force required at this time (this is called the maximum pulling load) is measured.

The maximum pull-out load is divided by the contact area between the H-section steel and the hardened cement to obtain the maximum pull-out strength of the anti-adhesion material.

Maximum pulling strength [kgf / cm ² ] = Maximum pulling load [kgf] / contact area between H-section steel and hardened cement [cm ² ] An anti-adhesion material (sample) was placed on the surface of 1 mH-section steel. The following method is used.

(1) When the form of the anti-adhesion material is liquid (paste, dispersion, viscous body, etc.), 160 g / m ² is uniformly applied in a dry state directly to the surface of the H-section steel. .

(2) When the anti-adhesive material is used in the form of a sheet, it is attached to the surface of the H-shaped steel by using a bonding agent such as an adhesive or an adhesive.

(3) When the form of the anti-adhesion material is used by wrapping it in a sheet shape, it is processed into a bag shape or a tubular shape, and the H-shaped steel is wrapped with the bag-shaped anti-adhesion material. However, the anti-adhesion material is obtained by applying the anti-adhesion composition to the sheet-like substrate,
When the amount of adhesion of the anti-adhesion composition can be freely set, the one which is uniformly applied so that the amount of adhesion becomes 160 g / m ² in a dry state is used. In addition, when the amount of adhesion of the anti-adhesion composition of the anti-adhesion material (sample) for which the maximum pull-out strength is measured is not known, or for a sample for which it cannot be freely set, the measurement is performed by itself.

The adhesive strength of the anti-adhesion material of the present invention is 0.01
9 kgf / cm ² or less, but 0.015 kg from the viewpoint of facilitating separation of the support and the cured product of the hydraulic composition.
It is preferably f / cm ² or less. Also, 0.01
More preferably, it is 0 kgf / cm ² or less. Further, it is preferably 0.005 kgf / cm ² or less. Still more preferably, it is 0.004 kgf / cm ² or less.

The maximum pull-out strength of the present invention is 0.019 kgf
/ Cm ² or less, separation of the cured product of the hydraulic composition from the support (drawing of the support) becomes extremely easy, and workability is improved.
Work safety is improved. Conversely, the maximum pull-out strength is 0.01
When it exceeds 9 kgf / cm ² , it is insufficient to suppress the adhesive strength between the cured product of the hydraulic composition and the support, and when the support is pulled out from the cured product of the hydraulic composition, the support is pulled out. A large amount of labor (tensile force) is required in the work, and the equipment involved in pulling out the work also increases, thereby reducing the workability of the worker. On the other hand, it is insufficient to reduce the labor required for peeling the cured product (hydrate) of the hydraulic composition from the support, and the workability of separating the cured product of the hydraulic composition from the support is reduced. Can't improve. That is, it may be difficult to separate the cured product of the hydraulic composition from the support.

The anti-adhesion material of the present invention comprises a water absorbing material and a bonding agent for adhering the water absorbing material, and includes, for example, the following forms.

A liquid or liquid dispersion or paste comprising a water-absorbing material such as a water-absorbing resin and a bonding agent such as an adhesive, a pressure-sensitive adhesive, a wax, and a grease. (This is referred to as an anti-adhesion composition.) It is pre-applied mainly to the surface of the H-section steel.

A sheet in which a water-absorbing material such as a water-absorbing resin is applied to the surface with a bonding agent such as an adhesive, a pressure-sensitive adhesive, a hot-melt agent, wax, or grease. This is applied to the surface of the H-section steel with a bonding agent, or used, for example, by processing the sheet into a bag and wrapping the H-section steel in the bag.

A combination of a water-absorbing material such as a water-absorbing fiber sheet and a bonding agent for attaching the sheet to the surface of the H-section steel.

It is to be noted that, for example, processing the sheet into a bag shape and wrapping it in the bag is more effective than coating or sticking directly on the surface of the H-shaped steel. Have a tendency to reduce the adhesive strength, and the two can be easily separated.

The maximum pull-out strength of the present invention is 0.019 kgf /
As a preferred specific example for realizing the cm ² or less, an anti-adhesion composition (anti-adhesion material) composed of “water-absorbing resin” and “alkali water-soluble resin”, or a sheet coated with this composition (Adhesion preventing material). The former composition is directly applied to a support, and the latter sheet is processed into a bag shape, wrapped around the support, and used.
"Alkaline water-soluble resin" acts as a bonding agent for adhering the water-absorbent resin to the support or sheet substrate, solubilizes when it comes into contact with alkaline water such as cement water, and does not hinder the water-absorbing swelling properties of the water-absorbent resin. Further, the “alkali water-soluble resin” has excellent coating properties and prevents the water-absorbing resin from falling off. This anti-adhesion material has an excellent effect of reducing the adhesive strength between the support and the hydraulic composition when they come into contact with each other, and achieves a maximum pull-out strength of 0.019 kgf / cm ² or less.

The sheet-like anti-adhesion material can be freely selected as a sheet-like substrate to which the anti-adhesion composition is adhered, and is wrapped in a support by selecting a sheet-like substrate having high strength. It is possible to prevent the anti-adhesion material from being damaged by external force and resistance when (supporting) or when embedding (punching) the support in the injected hydraulic composition, and the anti-adhesion property is reduced due to the damage. Can be prevented.

"Alkaline water-soluble resin" refers to a resin dissolved in a large excess of alkaline water prepared by dissolving sodium hydroxide at a ratio of 0.4% by weight in ion-exchanged water, and dissolved in ion-exchanged water. Insoluble resin.

The combination of an alkali water-soluble resin and a water absorbing material is the most preferred embodiment from the viewpoint of preventing adhesion. The water-absorbing material used in combination with the alkaline water-soluble resin is
It only needs to be made of a material that can absorb water,
A water-absorbent resin, a water-absorbent sheet, a water-absorbent fiber, a porous body such as a sponge or a felt capable of absorbing and retaining water twice or more its own weight are preferable. Among the water absorbing materials exemplified above, a water absorbing resin is particularly preferable.

The hydraulic composition according to the present invention contains water and materials such as cement and water glass which are hardened by water. More specifically, the hydraulic composition is, for example,
Including water and cement such as Portland cement and mixed cement, and if necessary, aggregates such as sand and gravel,
Contains cement admixtures, admixtures, reinforcements, etc. The hydraulic composition gradually hydrates (hardens) by mixing and kneading the cement and water, and becomes a hydrate (hardened body). The mixed water is gradually consumed by the hydration reaction. The type and combination of cement, aggregate, admixture, admixture, reinforcing material, and the like contained in the hydraulic composition, that is, the composition of the hydraulic composition is not particularly limited.

As the support according to the present invention, for example,
Examples thereof include a columnar substrate, a cylindrical columnar substrate, and a steel sheet pile (sheet pile) or a corrugated plate which is a long plate-shaped pile, but are not particularly limited. Specific examples of the columnar substrate include an H-shaped steel, an I-shaped steel, an iron column, a concrete pile, a pole, and the like. As a cylindrical columnar substrate,
Specifically, for example, a tubular pile (hollow pile) and the like can be mentioned. The support is generally used, for example, when constructing a ground foundation structure such as a retaining wall or a foundation in foundation work in the construction field and the civil engineering field. The shape, length, material, and the like of the support are not particularly limited. The support according to the present invention is an object that comes into contact with the hydraulic composition, and is separated from the hydrate of the hydraulic composition after the hydration of the hydraulic composition is completed, and the material is , Purpose, required strength and the like. Examples thereof include iron, plastic, concrete, and wood, but are not particularly limited.

In the present invention, the term "support" refers to an object buried or contacted with the hydraulic composition, and does not indicate only an object buried in the ground. Also,
The “support” in the present invention does not need to be entirely buried (contacted) in the hydraulic composition, and therefore, it is sufficient that at least a part is buried in the hydraulic composition. Further, the “support” in the present invention includes a support stored in, for example, a material yard before construction. Therefore, the category of the `` support '' in the present invention includes a support before construction, a support during construction, and a support extracted from a cured body of the hydraulic composition. I do.

The water-absorbing resin used in combination with the alkali-water-soluble resin may be any resin that swells by absorbing water and has a water absorption ratio of ion exchange water of 3 times or more with respect to its own weight. Although not required, a resin having a water absorption ratio of 10 times or more is more preferable.

Specific examples of the water-absorbing resin include cross-linked poly (meth) acrylic acid, cross-linked poly (meth) acrylate, and cross-linked poly (meth) acrylate having a sulfonic acid group. Crosslinked poly (meth) acrylate having polyoxyalkylene group, crosslinked poly (meth) acrylamide, crosslinked copolymer of (meth) acrylate and (meth) acrylamide, hydroxyalkyl (meth) acrylate Of copolymerized copolymers of poly (oxo) and (meth) acrylate, cross-linked polydioxolane, cross-linked polyethylene oxide, cross-linked polyvinyl pyrrolidone, cross-linked sulfonated polystyrene, cross-linked polyvinyl pyridine, and starch-poly (meth) acrylonitrile graft copolymer Compound, starch-poly (meth) acrylic acid (salt)
Graft cross-linked copolymer, reaction product of polyvinyl alcohol and maleic anhydride (salt), cross-linked polyvinyl alcohol sulfonate, polyvinyl alcohol-acrylic acid graft copolymer, polyisobutylene maleic acid (salt)
Crosslinked polymers and the like can be mentioned. One of these water-absorbing resins may be used alone, or two or more thereof may be used in combination. Further, other resins can be used in combination with the water-absorbing resin to such an extent that the various properties (water absorption ratio, etc.) of the water-absorbing resin are not impaired.

Among the water-absorbing resins exemplified above, those having a nonionic group and / or a sulfonic acid (salt) group are more preferable, and those having an amide group, a polyoxyalkylene group or a polyhydroxy group are more preferable. More preferred. Examples of the water absorbent resin include (meth)
Crosslinked copolymer of acrylate and (meth) acrylamide, hydroxyalkyl (meth) acrylate and (meth)
A cross-linked copolymer with an acrylate is exemplified. Further, a water absorbent resin having a polyoxyalkylene group is particularly preferred. Examples of the water-absorbing resin include a cross-linked copolymer of a (meth) acrylate having a methoxypolyoxyalkylene group and a (meth) acrylate. The water-absorbing resin having a methoxypolyoxyalkylene group is particularly excellent in swellability in alkaline water. Therefore, by using the water-absorbent resin, the operation of pulling out (separating) the support and the operation of peeling off the cured product of the hydraulic composition can be performed extremely easily.

Further, as the water absorbing resin according to the present invention, a resin obtained by polymerizing a monomer component containing a water-soluble ethylenically unsaturated monomer and, if necessary, a crosslinking agent is used. be able to. A water-absorbent resin obtained by (co) polymerizing an ethylenically unsaturated monomer is more excellent in swelling property with respect to water and is generally inexpensive. Therefore, by using the water-absorbing resin, the adhesive strength between the hydraulic composition and the support is reduced, and the support is pulled out (separation operation) or the cured product of the hydraulic composition is peeled off. Can be performed extremely easily and more economically. 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, a nonionic group and / or a sulfonic acid (salt)
Ethylenically unsaturated monomers having a group are more preferred. Examples of the monomer include 2- (meth) acrylamide-2-methylpropanesulfonic acid, 2- (meth) acryloylethanesulfonic acid, 2- (meth) acryloylpropanesulfonic acid, (meth) acrylamide, and hydroxyalkyl (Meth) acrylate, methoxypolyethylene glycol mono (meth) acrylate, and the like. Further, an ethylenically unsaturated monomer having a polyoxyalkylene group is particularly preferred. A water-absorbent resin obtained by polymerizing a monomer component containing methoxypolyethylene glycol mono (meth) acrylate is particularly excellent in swellability in alkaline water. Therefore, by using the water-absorbing resin, the operation of pulling out the support and the operation of peeling off the cured product of the hydraulic composition can be performed extremely easily. Further, when two or more ethylenically unsaturated monomers are used in combination as a monomer component, the ethylenically unsaturated monomer having a nonionic group and / or a sulfonic acid (salt) group in the monomer component is used. The ratio of monomer is 1
%, More preferably at least 10% by weight. When the above ratio is less than 1% by weight, even if a water-absorbent resin obtained by polymerizing the monomer component is used, the operation of pulling out the support or peeling the cured product of the hydraulic composition is performed. The work may not be easily performed. In the case where two or more ethylenically unsaturated monomers are used in combination as the monomer component, examples of a more preferable combination include, for example, a combination of an alkali metal (meth) acrylate such as sodium acrylate and acrylamide; A) Combination of alkali metal acrylate and methoxypolyethylene glycol mono (meth) acrylate, etc., but are not particularly limited. A water-absorbing resin is obtained by polymerizing the above monomer components. The method for polymerizing the monomer components, that is, the method for producing the water-absorbent resin, is not particularly limited. Also, the average molecular weight and shape of the water absorbent resin,
The average particle size and the like are determined based on the composition of the hydraulic composition and the p of alkaline water.
H, may be set according to the working environment and the like, and is not particularly limited, but the average particle diameter is 2,000 μm or less,
More preferably 500 μm or less, and even more preferably 15 μm or less.
It is more desirable to use a water-absorbing resin having a size of 0 μm or less. By using the water-absorbent resin having the average particle size, for example, the dispersibility or the mixing property of the water-absorbent resin in the solution of the anti-adhesion composition is improved, so that the handleability is further improved and the sheet-like base material is further improved. An anti-adhesion resin layer can be easily formed on the surface. Further, the amount of the water-absorbing resin contained in the resin layer per unit area can be increased in a uniform state.

The alkaline water-soluble resin constituting the anti-adhesion material of the present invention is obtained by adding sodium hydroxide to ion-exchanged water at a concentration of 0.1%.
Any resin that dissolves in alkaline water made alkaline by dissolving it at a ratio of 4% by weight and does not dissolve in ion-exchanged water may be used.
It is preferably at least mgKOH / g.

The alkaline water-soluble resin has a function as a bonding agent (binder) for adhering the water-absorbing resin to the support or the sheet surrounding the support. As will be described in detail later, in the case of forming a water-resistant coating on the surface of a coating film (anti-adhesion material layer) made of an anti-adhesion material, the alkali water-soluble resin is used as a water-resistance imparting agent. Is also used.

As the alkali water-soluble resin, for example, a resin having a substituent such as a carboxylic acid group, a sulfonic acid group and a phosphonic acid group is more preferable, and an α, β-unsaturated carboxylic acid monomer and a vinyl resin are preferable. A resin obtained by copolymerizing a monomer is excellent in solubility or swelling property in alkaline water and economical efficiency, and the above anti-adhesion composition (for example, a composition of a water absorbent resin and an alkaline water soluble resin)
Is excellent in various physical properties of a coating film formed by applying (adhering) to a support or a sheet wrapping the support,
In addition, the carboxylic acid group of the α, β-unsaturated carboxylic acid-based monomer is particularly preferable since it has a strong interaction with various materials and the resulting coating film has better adhesion to the support.

Specific examples of the α, β-unsaturated carboxylic acid monomer include α, β-unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid; itaconic acid, maleic acid, fumaric acid Α, β-unsaturated dicarboxylic acids such as maleic anhydride and itaconic anhydride; α, β-unsaturated dicarboxylic anhydrides such as maleic anhydride and itaconic anhydride; α and β such as maleic acid monoester, fumaric acid monoester and itaconic acid monoester -Unsaturated dicarboxylic acid monoester; and the like, but are not particularly limited. One kind of these α, β-unsaturated carboxylic acid monomers may be used alone, or two or more kinds thereof may be used in combination. Among the α, β-unsaturated carboxylic acid-based monomers exemplified above, acrylic acid and methacrylic acid are used to apply (adhere) an anti-adhesion composition to a support, and to provide a coating film having flexibility and toughness. Is more preferable.

Specific examples of the vinyl monomer include, for example, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, stearyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, Esters of C1-18 monohydric alcohols such as butyl methacrylate and stearyl methacrylate with (meth) acrylic acid; vinyl monomers containing nitrile groups such as acrylonitrile and methacrylonitrile; acrylamide, methacrylamide and the like An amide group-containing vinyl monomer; a hydroxyl group-containing vinyl monomer such as hydroxyethyl acrylate and hydroxypropyl methacrylate;
Epoxy group-containing vinyl monomers such as glycidyl methacrylate; α, β such as zinc acrylate and zinc methacrylate
Metal salts of unsaturated carboxylic acids; aromatic vinyl monomers such as styrene and α-methylstyrene; aliphatic vinyl monomers such as vinyl acetate; vinyl chloride, vinyl bromide, vinyl iodide, vinylidene chloride Halogen-containing vinyl monomers such as allyl ethers; maleic anhydrides such as maleic anhydride, monoalkyl maleate, dialkyl maleate; monoalkyl fumarate;
Fumaric acid derivatives such as dialkyl fumarate; maleimide derivatives such as maleimide, N-methylmaleimide, N-stearylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide; monoalkyl itaconate, dialkyl itaconate, itaconamide , Itaconic acid derivatives such as itaconic imides and itaconic amide esters; alkenes such as ethylene and propylene; dienes such as butadiene and isoprene; and the like, but are not particularly limited. One of these vinyl monomers may be used alone, or two or more thereof may be used in combination.

Among the vinyl monomers exemplified above, alkyl acrylate and alkyl methacrylate are formed by applying (adhering) the anti-adhesive composition to a support or a sheet surrounding the support. It is more preferable because the coating film has excellent flexibility, adhesion to a support or a sheet wrapping the support, weather resistance and toughness. When the proportion of the alkyl (meth) acrylate in the vinyl monomer is 30% by weight or more, the flexibility of the coating film, the adhesion to the support or the sheet surrounding the support, the weather resistance, etc. It is particularly preferable because the properties and toughness are further improved. Further, when the alkyl (meth) acrylate is an ester of a monohydric alcohol having 1 to 18 carbon atoms and (meth) acrylic acid, the flexibility of the coating film, the support or a sheet wrapping the support It is most preferable because the adhesion to, etc., weather resistance and toughness are particularly improved. In addition, when the alkyl (meth) acrylate is an ester of a monohydric alcohol having 1 to 4 carbon atoms and (meth) acrylic acid, the ester is more susceptible to hydrolysis with alkaline water, and It is particularly preferable because solubility in alkaline water is further improved.

The ratio of the α, β-unsaturated carboxylic acid monomer to the total amount of the α, β-unsaturated carboxylic acid monomer and the vinyl monomer is 9% by weight or more. More preferably, it is more preferably in the range of 9% by weight to 40% by weight. By setting the proportion of the α, β-unsaturated carboxylic acid monomer to 9% by weight or more, an alkali water-soluble resin having more excellent solubility in alkaline water can be obtained. By setting the ratio of the α, β-unsaturated carboxylic acid monomer in the range of 9% by weight to 40% by weight, the solubility in alkaline water is particularly excellent, and the neutralized and acidic water is excellent. On the other hand, an alkali water-soluble resin exhibiting water resistance can be obtained.

By copolymerizing the above α, β-unsaturated carboxylic acid monomer and vinyl monomer, an alkali water soluble resin can be obtained. The copolymerization method, that is, the method for producing the alkali water-soluble resin is not particularly limited. It is more preferable because it is easy to prepare a coating liquid for forming on it. The average molecular weight of the alkaline water-soluble resin may be set according to the composition of the hydraulic composition, the pH of the alkaline water, the working environment, and the like, and is not particularly limited. ~ 200,000
Within the range, a tougher coating film can be obtained, and an appropriate dissolution rate in alkaline water can be obtained. Since the alkaline water-soluble resin according to the present invention has excellent solubility in alkaline water, there is no possibility that the water-absorbent resin will inhibit volume expansion when the resin absorbs water and swells. Therefore, the water absorbent resin is
The water absorption characteristics (performance) can be sufficiently exhibited.

The acid value of the alkali water-soluble resin according to the present invention may be at least 15 mg KOH / g,
gKOH / g or more, more preferably 50 mg
KOH / g or more, more preferably 70 mg
KOH / g or more is particularly preferable.
Most preferably, it is in the range of OH / g to 500 mg KOH / g. Acid value of alkali water soluble resin is 15mg
When it is less than KOH / g, the solubility in alkaline water becomes poor, so that the operation of pulling out the support and the operation of peeling off the cured product of the hydraulic composition cannot be performed easily. Further, the acid value of the alkali water-soluble resin is 50
When the amount exceeds 0 mgKOH / g, the water resistance of the alkali water-soluble resin is reduced, so that a coating film formed by applying the anti-adhesion composition to a support or a sheet wrapping the support may have Contact with water exhibiting a neutral or acidic pH may result in dissolution or swelling and damage. For this reason, there is a possibility that the operation of pulling out the support or the operation of peeling off the cured product of the hydraulic composition may not be easily performed. From the above, the acid value is 300 m
It is more preferable that it is gKOH / g or more.

The alkaline water-soluble resin according to the present invention comprises:
Differential scanning calorimetry (DSC)
lorimetry)), the glass transition temperature is-
The glass transition temperature is preferably in the range of 80 ° C to 120 ° C, and has a low glass transition temperature in the range of -30 ° C to 20 ° C, while the glass of high temperature is in the range of 40 ° C to 100 ° C. More preferably, it has a transition temperature.
The method for measuring the glass transition temperature, that is, the measurement conditions for the differential scanning calorimetry will be described in detail later.

The glass transition temperature on the low temperature side is -30.degree.
By being in the range of ° C., the toughness of the coating film at a low temperature becomes higher, for example, such as in winter, even when the work site is at a low temperature, the coating film causes the support or the support to lose its toughness. The possibility of peeling from the wrapping sheet is reduced. Further, the glass transition temperature on the high temperature side is 40 ° C to 100 ° C.
, The coating film becomes sticky or softened even when the work site is at a high temperature, for example, in the summer, so that there is no possibility that the coating film is easily damaged by contact with a rope or the like. Therefore, the alkali water soluble resin,
While having a low-temperature glass transition temperature in the range of −30 ° C. to 20 ° C., and having a high-temperature glass transition temperature in the range of 40 ° C. to 100 ° C., the temperature change at the work site Stable coating that is hard to be influenced, that is, hard to peel or damage,
It is possible to form a coating film that is not sticky.

The ratio between the water-absorbing resin and the alkali water-soluble resin in the anti-adhesion material may be set according to the composition and combination of the two, the working environment, etc., and is not particularly limited. The ratio of the water-swellable resin to the total amount of the alkali water-soluble resin is more preferably 10% by weight or more, further preferably 20% by weight or more, and most preferably 30% by weight or more. When the above ratio is 95% by weight or less, more preferably 80% by weight or less, and still more preferably 70% by weight or less, falling off of the water-absorbing resin is reduced. The content of the water-absorbing resin in the anti-adhesion composition may be at least 10% by weight, and is not particularly limited.
It is more preferably at least 20% by weight, most preferably at least 30% by weight. When the content is 95% by weight or less, more preferably 80% by weight or less, and still more preferably 70% by weight or less, falling off of the water-absorbing resin is reduced.

The method of applying (adhering) the anti-adhesion composition to a support or a sheet wrapping the support to form a coating film is not particularly limited. A method in which a dispersion obtained by dispersing a water-absorbent resin and an alkali water-soluble resin in a dispersion medium such as an organic solvent, that is, a method of spraying a dispersion of an anti-adhesion composition onto a support or a sheet surrounding the support; Method: A method of coating with a coater that can accurately control the amount of coating may be employed. The anti-adhesion composition may be applied to a portion (location) where adhesion between the support or a sheet wrapping the support and the cured product of the hydraulic composition is to be prevented, but may be applied to other portions (location). No problem. In addition, as long as the above-mentioned adhesion can be prevented, there is no problem even if there is uneven coating or partial leakage. The dispersion applied to the support or the sheet surrounding the support may be dried if necessary. As a result, a coating film made of an anti-adhesion material is formed on the support or on the sheet surface (outer or inner surface) surrounding the support. In addition, as described above, when an alkali water-soluble resin is prepared by a solution polymerization method, a dispersion can be obtained only by mixing a water-absorbing resin into a solution after polymerization, so that the preparation of the dispersion is difficult. Easy.

Specific examples of the organic solvent include, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, benzene, toluene, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and the like. Is mentioned. And
Generally, when a low-boiling organic solvent is used, the time required for drying the dispersion medium is shortened, so that the time until a coating film is formed can be shortened. On the other hand, a high-boiling organic solvent is used. If it takes longer to dry the dispersion medium,
Workable time can be extended. Therefore, as the organic solvent, for example, an optimum compound may be selected according to the working environment and the situation. Alkaline water may be used as a medium, but if an aqueous medium is used, the water-absorbent resin swells, making brush coating and spraying difficult, and subsequent drying is also troublesome.

By making the form of the above-mentioned adhesion preventing material into a sheet, a bag, or a tube, the place where the composition is applied on the construction site and the application work become unnecessary, and the workability of the worker can be greatly improved. Can be.

Further, in the case of a sheet-like (bag-like or cylindrical) anti-adhesion material, when selecting a sheet-like base material to which an anti-adhesion composition comprising a water-absorbing material and an alkali-water-soluble resin is applied (applied), strength is selected. By selecting a strong (breakage-preventing) substrate, it is possible to prevent damage to the anti-adhesion material during construction and handling. This can prevent the adhesion between the support and the cured product of the hydraulic composition from deteriorating due to breakage, thereby greatly facilitating the separation of the two.

When the support is wrapped with a sheet-like substrate (bag, tubular body) coated with an anti-adhesion composition comprising an alkali water-soluble resin and a water-absorbing material (water-absorbing resin), It is required that the coating surface of the anti-adhesive composition is located “inside” the sheet-like material (anti-adhesion material), that is, the coating film is disposed between the support and the sheet-like substrate. It is preferable because the detachment of the film can be minimized and high anti-adhesion property can be maintained. For example, when an H-section steel (support) is driven into cement water mixed with earth and sand in an excavation hole, friction occurs between the cement water and the earth and sand. The coating film can be prevented from falling off without direct contact. Therefore, it is easy to pull out the support from the hardened cement body after hardening. In particular, when the same support is re-punched in cement water a plurality of times (re-injection of the H-section steel), the inner coating exhibits an excellent effect of not lowering the pull-out property of the support.

Further, under the condition that the H-shaped steel is hardly re-injected as described above, or under the condition that the wall surface in the excavation hole is stable and hard to collapse (there is little contact with earth and sand),
Placing the coating surface on the opposite `` outside '' rather than arranging it on the `` inside '' above keeps the surface extremely clean without adhesion of the peeled coating etc. on the drawn support surface Can be. Thereby, cleaning at the time of recycling the H-section steel (support) can be made almost unnecessary. Also,
When the coating surface is provided on the “outside”, when the support is mounted (wrapped) with the coated sheet-like base material (bag, tubular body), the coating surface does not directly contact the support surface. Therefore, since it can be easily mounted without being caught by the unevenness of the application surface, it is preferable in terms of workability rather than being arranged “inside”. In the case of applying on both surfaces, productivity is reduced because the application step is required twice, but the amount of the anti-adhesion composition applied on one surface can be reduced.

The adhesion amount of the coating film to a desired portion of the support or the sheet surrounding the support (or the amount of the anti-adhesion composition used for the contact portion) is preferably 40 g / m ^2.
As described above, it is more preferable that the weight is 50 g / m ² or more, and still more preferable that it is 80 g / m ² or more, but it is not particularly limited. Further, even if the amount of the coating film is increased more than necessary, the effect obtained is not so large, the time until the coating film is formed becomes long, and it is economically disadvantageous. Therefore, the amount of adhesion is preferably 700 g / m ² or less, more preferably 500 g / m ² or less, and most preferably 300 g / m ² or less.

The alkali water-soluble resin in the above coating film does not dissolve even when it comes into contact with water having a pH in a neutral or acidic range such as rain. That is, the alkali water-soluble resin has excellent water resistance, and does not damage even when it comes into contact with water having a pH in a neutral or acidic range. Therefore, when applying, it is convenient to apply the anti-adhesion composition to a support or a sheet wrapping the support in advance, and then store it. There is no need to apply it to the sheet wrapping the sheet, which simplifies and rationalizes the work, and enables quick construction. on the other hand,
The alkaline water-soluble resin dissolves when it comes into contact with alkaline water. That is, the anti-adhesion material is such that the alkaline water-soluble resin starts dissolving when it comes into contact with the hydraulic composition, and forms a layer of a swollen water-absorbing resin between the hydraulic composition and the support. Has become. Therefore, workability such as an operation of pulling out the support from the cured body of the hydraulic composition and an operation of peeling the cured body of the hydraulic composition from the support can be improved.

Further, for example, when the support or the sheet wrapping the support is stored, even if the support or the sheet wrapping the support is piled up in a material storage area or the like, the water-absorbent resin may be subjected to rain or night dew. Or, if necessary, apply (adhere) a water resistance imparting agent to the surface of the coating film (anti-adhesion layer) made of the anti-adhesion composition so as not to swell by absorbing water from the ground. Thereby, a water-resistant coating can be formed.

The water resistance imparting agent may be any compound that can prevent the water absorbing resin from swelling by forming a water resistant film on the surface of the coating film (top coating). Examples of the water resistance imparting agent include the above-described alkali water-soluble resins; conventionally known water repellents such as waxes and silicone-based water repellents; and the like. What is necessary is just to do and it does not specifically limit. In addition, the method for forming a water-resistant coating by applying (adhering) a water-resistance imparting agent to the surface of a coating film is not particularly limited. A dispersion liquid dispersed in a dispersion medium such as an organic solvent,
That is, a method of spraying the dispersion of the water resistance imparting agent onto the surface of the coating film; The dispersion applied to the surface of the coating film may be dried if necessary. Thus, a water-resistant coating made of a water-resistance imparting agent is formed on the coating film surface. The adhesion amount of the water-resistant coating is 50 g /
About m ² is sufficient, but is not particularly limited.

By forming the water-resistant coating, for example, when the support or the sheet enclosing the support is stored, even if the support or the sheet enclosing the support is piled up in a material storage area or the like, The water-absorbing resin does not swell by absorbing rain, night dew, or moisture from the ground. In other words, since the water-resistant coating is formed, for example, even if the support or the sheet wrapping the support is wetted before the application using the support or the sheet wrapping the support, the water-resistant coating does not absorb water. In order to prevent the conductive resin from swelling, there is no need to cover the support or the sheet surrounding the support with, for example, a waterproof sheet, or to store the support or the sheet surrounding the support in an indoor material storage space. Therefore, the support or the sheet surrounding the support can be stored simply and inexpensively. In addition, for example, the alkali water-soluble resin forming the water-resistant coating starts dissolving when it comes into contact with the hydraulic composition. Therefore, at the time of construction, it is not necessary to peel off the water-resistant coating from the surface of the coating film before performing the construction. That is, the structure can be constructed using the support on which the water-resistant coating is formed or the sheet surrounding the support as it is.

As the sheet-like base material to which the anti-adhesion composition is applied at the time of producing the sheet-like anti-adhesion material, specifically, for example, a split-fiber nonwoven fabric (for example, Warif “trade name”)
Etc.), carpet, felt, asbestos cloth, asbestos felt,
Non-woven fabrics such as glass fiber non-woven fabric, glass fiber reinforced plastic, stitch-bonded non-woven fabric, needle punched non-woven fabric, etc .; , Blended fabrics such as a fabric obtained by blending polyester fibers and cotton fibers, etc .; closed cells and polystyrene, polyethylene, polypropylene, vinyl chloride resin, urethane resin, phenol resin, rubber foam, etc. And / or a foam formed with open cells; an elastomer sheet made of urethane rubber, silicone rubber, fluorine rubber, ether rubber, acrylic rubber, butyl rubber, neoprene (chloroprene rubber), butadiene-acrylonitrile copolymer, natural rubber, or the like; Polyethylene and poly Plastic sheets made of propylene, polyethylene terephthalate, polyamide (nylon), vinyl chloride resin, acrylic resin, etc., leather sheets and wood sheets, natural sheets such as waterproof paper sheets and cardboard sheets, aluminum, iron, copper, Sheets such as metal sheets made of silver, etc., alloy sheets made of stainless steel, stainless steel fiber sheets, ceramic fiber sheets, metal foils made of aluminum, iron, copper, silver, etc., alloy metal foils made of stainless steel, etc .; polyethylene Net or mesh made of aluminum, polypropylene, polyethylene terephthalate, polyamide (nylon), vinyl chloride resin, acrylic resin, etc., net or mesh made of aluminum, iron, copper, silver, etc., net or mesh made of alloy such as stainless steel, etc. Net mesh like; and the like. One of these materials may be used alone, or two or more thereof may be used in combination (composite).

Among the above examples, since they are excellent in water permeability and processability and are inexpensive, they are split fiber nonwoven fabric, needle punched nonwoven fabric, flat yarn fiber fabric, cotton fabric, hemp fabric, belt-like fabric, synthetic resin fabric, and Particularly preferred is a blended fabric.

In the above examples, cuts and holes may be formed as necessary for materials having no water permeability, such as sheets. in this case,
The shape, size, number, and formation position of the cuts and holes are not particularly limited, and are within a range that can maintain the strength at which the sheet-shaped substrate is not damaged even when the external force or resistance is applied. Can be set as appropriate.

The thickness of the sheet substrate may be set according to the material, and is not particularly limited.
It is more preferably in the range of 01 mm to 10 mm, and 0.05
mm to 8 mm is more preferable, and 0.2 mm to 8 mm
Particularly preferred is a range of 5 mm. If the thickness of the sheet-shaped substrate is greater than 10 mm, the flexibility of the coating material may be reduced. Further, since the coating material becomes bulky, its handling and storage properties may be reduced. If the thickness of the sheet-like base material is less than 0.01 mm, there is a possibility that strength that can withstand external force cannot be maintained.

[0076] Incidentally, the basis weight of the sheet-like substrate may be set according to the material and thickness, but are not particularly limited, in the range of 10g / m ² ~10,000g / m ² still more preferably, in the range of 20g / m ² ~1,000g / m ² is more preferred.

The tensile strength (wet tensile strength) of the sheet-like substrate in a state of being wet with water is not particularly limited.
It is more preferably 1 kgf / 25 mm or more.
0 kgf / 25 mm or more is more preferable,
It is particularly preferred that it is 30 kgf / 25 mm or more.
When the wet tensile strength is 1 kgf / 25 mm or more, the sheet-like substrate can maintain a strength that does not break even when the external force or resistance is applied. When the tensile strength of the sheet-like substrate is less than 1 kgf / 25 mm, the sheet-like substrate is easily broken or torn when an external force is applied.

The above-mentioned wet tensile strength was determined by using a test piece (sheet-like substrate) which was cut into a size of 25 mm in width and 20 cm in length and immersed in ion-exchanged water for 30 minutes to be sufficiently wetted. Using a low-speed elongation tensile tester based on a tensile test method (tensile strength) of 1096 (general textile test method), a tensile speed of 20 mm / min, and a grip interval of 10 c
The measurement was performed under the condition of m. It can be determined that the larger the measured value (unit: kgf / 25 mm) obtained by the tester, the higher the tensile strength of the sheet-shaped substrate.

The ratio of the anti-adhesive composition when dried to the sheet-like base material, that is, the adhesion amount of the alkali water-soluble resin and the water-absorbent resin per unit area of the sheet-like base material is determined by the composition and combination of the two. , May be set according to the work environment and the like, and is not particularly limited.
more preferably in the range of ^{g / m 2 ~10,000g / m 2} , more preferably in the range of ^{10g / m 2 ~5,000g / m 2} , in the range of 20g / m ² ~1,000g / m ² Is particularly preferred. The ratio of the alkali-water-soluble resin and the water-absorbing resin to 100 parts by weight of the sheet-like substrate is more preferably in the range of 1 part by weight to 10,000 parts by weight.
The range is more preferably from 0 to 1,000 parts by weight, particularly preferably from 20 to 500 parts by weight.

Examples of the method of wrapping (covering) the support with the anti-adhesive material include, for example, a method of covering the support with an anti-adhesive material formed in a bag shape or a tubular shape, and a method of covering the support with a bag shape. Or a method of inserting into a cylindrically formed support,
A method of wrapping the support with an anti-adhesion material formed in a sheet shape, a method of fixing the anti-adhesion material to the support using a fixing jig or the like can be adopted, but is not particularly limited. . Also, when wrapping the support with an anti-adhesion material,
More preferably, the anti-adhesion material is wrapped so as to conform to the shape of the support. Thereby, the positioning accuracy (implantation accuracy) when the support is embedded is further improved. In addition, as a method of forming the adhesion preventing material in a bag shape or a cylindrical shape, specifically, for example, a method of bonding using an adhesive, a method of fusing by heat sealing, a method of sewing, a wire or a string, etc. Various methods such as a binding method can be employed, but are not particularly limited. Further, the appearance of the anti-adhesion material is not particularly limited, but a state of being wound up in a roll shape or a state of being folded in a bellows form is more preferable from the viewpoint of handleability and workability. .

The time at which the support is wrapped (covered) with the anti-adhesive material is not particularly limited, and may be an appropriate time before the support is carried to the work site. It may be an appropriate time during storage of the preventive material, or an appropriate time before the work of burying the support is started. That is, the support may be covered with the anti-adhesion material at the time of burying. Also,
In the case of using an anti-adhesion material formed in a bag shape or a tubular shape, the anti-adhesion material only needs to be formed in these shapes when embedded.

One embodiment of the present invention will be described in more detail with reference to FIGS. ◆ Figure 1
As shown in FIG. 1, a ground foundation structure as a structure according to the present embodiment is embedded in a ground 1 and includes a cured body 2 of a hydraulic composition and a support 3. In the above-mentioned ground substructure, for example, after forming an excavation hole in the ground 1 and loosely inserting the support 3, a hydraulic composition is poured around the support 3 and hydrated (hardened). To form a cured product 2 of the hydraulic composition, or after embedding the support 3 in a hydraulic composition placed in a drilling hole, and then curing the hydraulic composition to obtain a hydraulic composition. It is constructed by forming a cured product 2.

Prior to the above-mentioned construction, an anti-adhesion material 4 is uniformly applied to the surface of the support 3 (an anti-adhesion material is interposed between the hydraulic composition and the support). ing). As shown in FIG. 2, the anti-adhesion material 4, which is a coating film,
The water-absorbing resin particles 4a and the resin particles 4a
And an alkaline water-soluble resin 4b adhered to the surface of the substrate.

In the above configuration, the alkaline water-soluble resin 4b of the anti-adhesion material 4 dissolves when it comes into contact with the alkaline water contained in the hydraulic composition. On the other hand, the water-absorbing resin particles 4a of the adhesion preventing material 4 swell by absorbing alkaline water. Therefore, after the hardening of the hydraulic composition is completed, a layer of the water-absorbent resin particles 4a that have swollen by absorbing water is provided between the cured body 2 of the hydraulic composition and the surface of the support 3. It is formed. That is, the hydraulic composition cured body 2 and the support 3
The layer of swollen water-absorbent resin particles 4a is formed between the surface and the surface of the substrate, so that the adhesion between the two can be suppressed.
Thereby, when the support 3 is pulled out from the cured body 2 of the hydraulic composition, the swollen water-absorbent resin particles 4a exhibit a lubricating effect, and thus the support 3 becomes slippery. Therefore, the labor (tensile force) in the operation of pulling out the support 3 from the cured body 2 of the hydraulic composition can be further reduced, and the workability of the operation can be improved. Further, by drying the water-absorbent resin particles 4a, a gap can be formed between the cured body 2 of the hydraulic composition and the surface of the support 3, so that the workability of the above operation is further improved. Can be done. therefore,
According to the above configuration, it is possible to provide an adhesion preventing material that can be suitably used for a ground foundation structure (structure).

Another embodiment of the present invention will be described in more detail with reference to FIG. Note that, for convenience of description, components having the same functions as those shown in the drawings of the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 3, a ground substructure as a structure according to the present embodiment is buried in the ground 1, and comprises a hardened hydraulic composition 2, a cylindrical support 13, It is composed of The above-mentioned ground substructure, for example, forms the cured body 2 of the hydraulic composition by embedding the support 13 in the hydraulic composition poured into the excavation hole and then curing the hydraulic composition. It is constructed by doing. The cured body 2 of the hydraulic composition is also formed inside the support 13. The adhesion preventing material 4 is uniformly applied to the upper portion (pile head) on the inner surface of the support 13 prior to the execution of the above-mentioned construction.

In the above structure, the alkaline water-soluble resin 4b of the anti-adhesion material 4 dissolves when it comes into contact with the alkaline water contained in the hydraulic composition. On the other hand, the water-swellable resin particles 4a of the adhesion preventing material 4 swell by absorbing alkaline water. Therefore, after the hardening of the hydraulic composition is completed, the pile head 2a of the cured body 2 of the hydraulic composition and the support 1
A layer of the water-absorbent resin particles 4a that has swollen by absorbing water is formed between the inner surface of the resin 3 and the inner surface of the resin-absorbing resin 3. That is, the above-mentioned pile head 2
Since a layer of swollen water-absorbent resin particles 4a is formed between a and the inner surface of the support 13, the adhesion between the two can be suppressed. Thereby, when peeling the pile head 2a of the cured product 2 of the hydraulic composition from the support 13, the layer of the swollen water-absorbent resin particles 4a can suppress the adhesion between the two. Labor can be reduced, and workability of the work of peeling the pile head 2a from the support 13 can be improved. Further, the water-absorbing resin particles 4a ...
By drying, a gap can be formed between the pile head 2a and the inner surface of the support 13, so that the workability of the above operation can be further improved. Therefore, according to the above configuration, it is possible to provide an anti-adhesion material that can be suitably used for the ground foundation structure (structure).

Regarding still another embodiment of the present invention,
This will be described in more detail with reference to FIG. Note that, for convenience of description, components having the same functions as those shown in the drawings of the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 4, a ground substructure as a structure according to the present embodiment is embedded in the ground 1, and comprises a cured body 2 of a hydraulic composition and a cylindrical support 13. It is composed of The above-mentioned ground foundation structure, for example,
After the support 13 is inserted into the borehole, the hydraulic composition is cast inside the support 13 and hydrated to form the cured body 2 of the hydraulic composition. The adhesion preventing material 4 is uniformly applied to the upper portion (pile head) on the inner surface of the support 13 prior to the execution of the above-mentioned construction.

In the above configuration, that is, after the curing of the hydraulic composition is completed, the cured product 2 of the hydraulic composition
A layer of swollen water-absorbing resin particles 4a is formed between the pile head 2a and the inner surface of the support 13, so that the adhesion between the two can be suppressed. Thereby, when peeling the pile head 2a of the cured body 2 of the hydraulic composition from the support 13, the layer of the swollen water-absorbing resin particles 4a can suppress the adhesion between the two, so that labor is required. Can be reduced, and the workability of the operation of peeling the pile head 2a from the support 13 can be improved. Further, by drying the water-absorbent resin particles 4a, a gap can be formed between the pile head 2a and the inner surface of the support 13, so that the workability of the above operation can be further improved. .

Therefore, according to the above configuration, an anti-adhesion material that can be suitably used for the ground foundation structure (structure), and a support body that can quickly construct the ground foundation structure are provided. can do.

Next, as a method of wrapping (covering) the support with a sheet (anti-adhesion material) coated with the anti-adhesion composition,
More specifically, for example, as shown in FIG. 5A, the support 22 is lifted using a crane 26, and the string 23 passed through a pulley 25 provided at the tip of the crane 26 is attached to the sheet. Is attached to a bag-shaped or cylindrical anti-adhesion material 21 made by processing the above, and then the bag-shaped or cylindrical anti-adhesion material 21 is pulled downward by, for example, an operator 24 pulling a string 23. After being inserted into the support body 22 so as to be worn from above, the worker 24 further pulls the string 23 as shown in FIG.
A method of pulling up and mounting the anti-adhesion material 21; fixing the upper end by inserting the anti-adhesion material formed in a tubular shape so as to cover it from above, and then lifting the support using a crane. Then, the string attached to the lower end of the anti-adhesion material is pulled down by an operator, for example, so that the anti-adhesion material is pulled down and attached; the anti-adhesion material formed in a bag or a tube is placed on the ground or the like. After placing, insert the support into the anti-adhesion material, and then pull up the anti-adhesion material to attach and fix it; after mounting the support on the ground or the like, the support is bag-shaped or tubular. A method of inserting the anti-adhesive material formed in the above, then lifting up the support, pulling up the anti-adhesive material, mounting and fixing it; as shown in FIG. Place support 22 on top of After placing with down 26 or the like, as shown in FIG. (B) · (c), wraps the support 22 by adhesive-preventing member 30, then, as shown in FIG. 2 (d),
A method of fixing the anti-adhesion material 30 using the fixing jigs 31; a method of sandwiching and fixing the support between the anti-adhesion materials folded in a bellows shape; and both ends of the anti-adhesion material on the upper and lower parts of the support A method of fixing both ends of the anti-adhesion material to the upper and lower portions of the support, and fixing the center of the anti-adhesion material using a wire (number line), a string, a belt, a gum tape, or the like; A method of fixing a part of the anti-adhesive material to the upper part of the body and hanging the remaining part of the anti-adhesive material along the support can be adopted, but is not particularly limited.

Among the above-described methods, a method of inserting and attaching a bag-shaped or cylindrical anti-adhesive material to a support so that the anti-adhesive material can be worn from below, and a method of forming the support in a sheet shape The method of wrapping with the provided anti-adhesion material is more preferable because the workability of the covering work is excellent. The method for fixing the anti-adhesion material to the support is not particularly limited. Further, as the fixing jig 31, specifically, for example, a binder such as a washing pinch, a cap such as a clip, a rubber hose, or a tube formed by dividing a tube such as a heat insulating foam, a wire (number line), a string, Examples include a belt and a gum tape, but are not particularly limited.

Further, on the surface layer of the sheet-, tape-, bag- or tube-shaped anti-adhesive material, a fiber woven fabric (blended), a non-woven fabric such as a felt, a split fiber non-woven fabric such as a warif, various films, a molten laminated film ( Composite by melting), rubber sheet, various foams (porous), leather sheet, cardboard,
By laminating a reinforcing material such as a thin metal sheet, various nets or meshes, it is possible to further prevent a decrease in anti-adhesion property due to breakage during construction. Lamination can be performed by sewing, a bonding agent, melt lamination, or the like. The portion to be laminated may be a part of the adhesion preventing material, and it is preferable to reinforce a seam (sewn portion) portion or a portion to which a load of the support is directly applied when processing into a bag or a tube. For example, as shown in FIG. 5, the lowermost portion when the support (H-section steel) is lifted may be easily damaged by the direct load at a sharp angle, and thus may be easily damaged by carpet or felt. It is preferable to reinforce with the above-mentioned reinforcing material.

As a measure for preventing damage, it is necessary to attach a mounting device having a buffering effect to a sharp corner at the lower end of the support in advance, in order to prevent a decrease in the anti-adhesive property due to breakage of the anti-adhesive material. Is preferred. The wearing tool is not particularly limited as long as it has a buffering effect (cushioning material). For example, polystyrene, polyethylene, polypropylene, vinyl chloride resin, urethane resin,
Foams that form closed or open cells such as phenolic resin; rubber foam; rubbers such as urethane and silicone;
Leather; wood; cardboard; cardboard; split fiber non-woven fabric; non-woven fabric such as carpet and felt; The shape of the mounting device may be any as long as it can be fixed with a fixing material such as a binder or an adhesive that is sandwiched in a shape corresponding to the shape of the support. It is particularly preferable that the mounting device itself can sandwich and fix the corner portion of the support bottom, such as a heat insulating material of a certain water pipe).

According to the above construction, the water-absorbent resin swollen by absorbing water is interposed between the hydraulic composition and the support (for example, steel sheet pile, H-section steel, or cylindrical columnar substrate). Is formed. That is, since a layer of the swollen water-absorbing resin can be formed between the cured body of the hydraulic composition and the support, adhesion between the two can be suppressed. Thereby, when separating the support from the cured product of the hydraulic composition, the work of separating the support from the cured product of the hydraulic composition is performed by the swollen water-absorbing resin exerting a lubricating or peeling effect. Can be further reduced, and the workability of the work can be improved. On the other hand, when the cured body of the hydraulic composition is peeled from the support, the adhesion between the two can be suppressed by the swollen water-absorbent resin layer, so that the labor can be reduced, and the hydraulic composition can be reduced. The workability of the operation of peeling the cured product from the support can be improved. Further, by drying the water-absorbent resin, a gap can be formed between the cured body of the hydraulic composition and the support, so that the workability of the above-mentioned various operations can be further improved. Therefore, according to the above configuration, it is possible to provide an adhesion preventing material that can be suitably used for the structure.

When the support is pulled out from the cured product of the hydraulic composition, a cavity (hole) having the same shape as that of the support is formed in the structure. The cavity, for example,
It can be used as a drain. Also, in the cavity,
Electric wires, gas pipes, water pipes, etc. can be inserted.

[0098] The structure according to the present invention may be a base for installing a road sign or the like. In other words, by forming a structure using a support having a size (shape, length, etc.) corresponding to the embedded portion of the road sign desired to be installed, the support is pulled out and the road sign is inserted. , Road signs can be installed.

The support used in the present invention includes those used for maintaining the hydraulic composition in a desired shape until the curing of the hydraulic composition is completed.

[0100]

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 alkali water-soluble resin is determined according to JIS.
It was measured based on the test method described in the application clause 4.3 of K6901 “Test method for liquid unsaturated polyester resin”.
However, when the alkali water-soluble resin 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 for dissolving.

When the sample is a mixture of an alkali-water-soluble resin and a water-absorbent resin or a coating film thereof, the sample is dissolved or dispersed in an organic solvent and then filtered to obtain a filtrate containing the alkali-water-soluble resin dissolved therein. The filtrate is separated from the water-soluble polymer, and the acid value of the filtrate is determined by the method of JIS. The weight of the non-volatile content obtained by drying the filtrate is defined as the total amount of the alkali water-soluble resin.

The differential scanning calorimetry of the alkali water-soluble resin was performed using a DSC220C manufactured by Seiko Denshi Kogyo KK. The measurement conditions are as follows. That is, in a nitrogen gas atmosphere, 10 mg of the sample was heated to 150 ° C., kept at that temperature for 5 minutes, rapidly cooled to −100 ° C., and kept at that temperature for 5 minutes. Subsequently, the above sample was heated at a rate of 10 ° C. /
The temperature was raised to 150 ° C. in minutes. Then, the temperature showing the inflection point in the DSC curve was read according to a conventional method, and the temperature was taken as the glass transition temperature of the alkali water-soluble resin.

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 10 L and having a thermometer and a blade (stirring blade), the inner surface of which is lined with ethylene trifluoride, is used as a reactor, and methoxypolyethylene glycol monomethacrylate ( 2,247 parts of 43 mol% of sodium methacrylate
2,448 parts of an aqueous solution, 4.74 parts of a polyethylene glycol diacrylate as a crosslinking agent, and 741 parts of ion-exchanged water as a solvent were charged. The proportion of the crosslinking agent in the monomer component is 0.07 mol%. 4 on the jacket
By flowing warm water at 5 ° C., the above aqueous solution was heated to 45 ° C. while stirring under a nitrogen gas stream. Next, 59 parts of a 10% by weight aqueous solution of 2,2′-azobis- (2-amidinopropane) dihydrochloride (molecular weight: 271.27, chemical product V-50, manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator was added. Upon addition, polymerization was initiated. After stirring for 20 seconds after the addition,
The stirring was stopped and the mixture was allowed to stand. The ratio of the polymerization initiator to the monomer component is 0.15 mol%.

The polymerization reaction was started immediately after the addition of the polymerization initiator, and the internal temperature reached 85 ° C. (peak temperature) after 74 minutes. During this time, the temperature of the jacket was increased to be equal to the temperature of the reaction solution. Next, 8 on the jacket
The contents were aged for an additional 30 minutes while flowing hot water at 0 ° C. 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 120 ° C. for 4 hours using a hot air circulating drier. After drying, the dried product was pulverized using a desktop simple pulverizer (manufactured by Kyoritsu Riko Co., Ltd.). Thus, a water-absorbent resin having an average particle diameter of 150 μm was obtained.

On the other hand, an alkaline water-soluble resin was prepared by the following method. That is, a thermometer, a stirring blade, a reflux condenser,
And 0.45 kg of acrylic acid, 2.4 kg of ethyl acrylate in a 50 L capacity tank reactor equipped with a dropping device,
0.15 kg of methyl methacrylate, 12 g of 2,2′-azobis- (2,4-dimethylvaleronitrile) as a polymerization initiator, and 3 k of methyl alcohol as a solvent
g. Acrylic acid 1.05 was added to the dropping device.
kg, 2.1 kg of methyl acrylate, 3.85 kg of methyl methacrylate, 28 g of 2,2′-azobis- (2,4-dimethylvaleronitrile), and 7 kg of methyl alcohol were 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, 10 kg of methyl alcohol was mixed with the contents to obtain a 33% by weight methyl alcohol solution of an alkali water-soluble resin.

The alkali water-soluble resin obtained has an acid value of 1
17 mgKOH / g. As a result of performing differential scanning calorimetry on the alkali water-soluble resin, the alkali water-soluble resin had two glass transition temperatures in the range of -80 ° C to 120 ° C.

The water absorbent resin 50 prepared as described above
By mixing, pulverizing and dispersing 150 parts by weight of a 33% by weight methyl alcohol solution of an alkali water-soluble resin, the maximum withdrawal strength of the dispersed mixed liquid is 0.0037 parts by weight.
An anti-adhesion material 1 of kg / cm ² was obtained. The dry weight ratio of the water-absorbent resin and the alkali-water-soluble resin in the dispersion mixture (water-absorbent resin / alkali-water-soluble resin) is 1/1. Then, the obtained dispersion-mixed liquid anti-adhesion material 1
Is a support H-100mm × 100mm (width),
H-shaped steel with a length of 1000mm (weight of steel material 16.9kg)
200 g / m ² (dry solid content) was uniformly applied to the surface of the sample. This made it possible to form a coating film that was not easily peeled or damaged and was not sticky. Further, the coating film had sufficient adhesion to the H-section steel and did not easily peel off even when rubbed with an iron spatula or the like.

As the hydraulic composition, a cement composition comprising 755 parts by weight of tap water, 175 parts by weight of cement, 488 parts by weight of clay, and 18 parts by weight of bentonite was prepared, and a bottomed paper having an inner diameter of 250 mm was prepared. The cement composition was injected into a void tube (manufactured by Showa Marutsu, product name: Sonoboid) so that the depth became 800 mm or more. The bottom of the void tube was closed by closing it with a plastic bag.

Next, the H-section steel was vertically embedded in the cement composition by a length of 850 mm, and then the cement composition was hardened.

After a lapse of 7 days, the H-section steel was pulled out of the hardened cement composition. The H-section steel could be easily pulled out from the hardened cement composition, and the surface of the H-section steel had a layer of a water-absorbent resin swollen by absorbing water. The pulling load (tensile force) required for the pulling operation is 1
It was 8 kgf. Therefore, by applying the dispersion-mixed liquid anti-adhesion material of the present invention to the surface of the H-section steel, the adhesion between the H-section steel and the cured product of the cement composition can be suppressed, and the workability is improved. I found that I could do it.

Example 2 An alkaline water-soluble resin was prepared by the following method. Specifically, 0.525 kg of acrylic acid, methyl acrylate 1.
725 kg, ethyl acrylate 2.4 kg, methyl methacrylate 2.85 kg, 2,2′-azobis- (2,4
30 g of dimethylvaleronitrile) and 15 kg of methyl alcohol.

The above methyl alcohol solution was heated to 65 ° C. while stirring under a nitrogen gas atmosphere, and reacted for 5 hours. Thus, a 33% by weight methyl alcohol solution of the alkali water-soluble resin was obtained. The acid value of the obtained alkali water-soluble resin was 51 mgKOH / g.

A 33% by weight solution of the alkali water-soluble resin prepared as described above in 150% by weight of a methyl alcohol solution, and a commercially available water-absorbent resin (Aqualic CA: W-4) were pulverized and passed through a mesh having an aperture of 180 μm. 50 parts by weight of a water-absorbent resin (manufactured by Nippon Shokubai Co., Ltd.)
By dispersing, an anti-adhesion material 2 having a maximum pull-out strength of 0.0055 kg / cm ² of the dispersed mixed liquid was obtained.

Then, using the obtained dispersion mixture (anti-adhesion material 2), the surface of the H-section steel was uniformly coated with 100 g / m 2.
Under the same conditions as in Example 1 except that an amount of ² (dry solids) was applied, the H-shaped steel was pulled out from the hardened cement composition. The pulling load at that time was 82 kgf, and it was easy to pull out.

By applying the anti-adhesion material 2, it was found that the adhesion between the H-shaped steel and the cured product of the cement composition could be suppressed, and the workability could be improved.

Example 3 10 parts by weight of a water-absorbing resin and a 33% by weight methyl alcohol solution 273 of an alkali water-soluble resin (acid value: 117 mgKOH / g) prepared by the method described in Example 1 By mixing and dispersing with a weight part, the maximum pull-out strength of the dispersed mixed liquid becomes 0.0
An anti-adhesion material 3 of 17 kg / cm ² was obtained. The weight ratio of the water-absorbent resin to the alkali water-soluble resin in the dispersion mixture is 1/9. Then, the obtained dispersion mixture is
Cold-rolled steel plate 70 mm wide x 150 mm long x 0.8 mm thick (support: SPC manufactured by Japan Test Panel Co., Ltd.
(C-SB). As a result, the amount of adhesion on the surface of the steel plate (hereinafter referred to as a test piece) is 1
A coating film having a thickness of 00 g / cm ² was formed.

Next, as a water resistance imparting agent according to the present invention, a 25% by weight methyl alcohol solution of an alkali water-soluble resin prepared by the method described in Example 1 was used. The solution was uniformly applied so that the amount was 50 g / m2.

The water resistance of the water resistant coating was evaluated. That is, a test piece (a test piece having a coating film and a water-resistant coating formed thereon, hereinafter, referred to as a test piece a) is immersed in deionized water, and changes with time of the coating film are visually observed to obtain water resistance. The water resistance of the coating was evaluated. In the case of poor water resistance, deionized water passes through the water-resistant coating and swells the water-absorbing resin contained in the coating,
The water-absorbent resin appears white and floating. Therefore, the water resistance is evaluated as “excellent” when less than 10% of the entire coating film appears to be in a floating state, “good” when the same portion is 10% or more and less than 40%, Is 40% or more and less than 90%, "OK";
The case of 0% or more was evaluated as "impossible" on a four-point scale.

Similarly, a test piece having only a water-resistant coating formed on its surface (hereinafter referred to as test piece b) and a test piece having only a coating formed on its surface (hereinafter referred to as test piece b)
Test piece c) was evaluated for water resistance.

Since the test pieces a and b had a water-resistant coating, they were evaluated as “good” or “good” even when immersed in deionized water for 7 hours, indicating that they had excellent water resistance. understood. That is, it was found that the water-resistant coating was excellent in water resistance. Further, it was found that the alkali water-soluble resin according to this example had excellent water resistance, and did not cause peeling of the coating film even when wet with water. On the other hand, test piece c
Has no water-resistant coating, so there is a portion where the water-absorbing resin contained in the coating is exposed, and the evaluation becomes "poor" just by immersing in deionized water for 5 minutes. It turned out to be bad.

Next, a 1: 2 mortar was prepared, the test piece a was vertically embedded in the mortar by a length of 135 mm, and the mortar was cured. After a lapse of 7 days, the test piece a is pulled out of the cured mortar,
The pulling load required for the drawing operation was measured, and the width of the hole formed after the test piece a was pulled out was measured. The drawing load was 3.2 kgf and the width of the hole was 2.
It was 8 mm.

Similarly, a commercially available wax having a thickness of 15
A test piece (hereinafter, referred to as a test piece d) applied to a thickness of 0 μm, and a test piece (hereinafter, a test piece e) applied to the wax to a thickness of 400 μm.
), And the pull-out load of a test piece having nothing applied to the surface (hereinafter, referred to as a blank test piece). The pull-out load of test piece d is 12.1 kgf
And the width of the hole was 0.85 mm. The test piece e had a pull-out load of 13.4 kgf and a hole width of 1.2 mm.

The test piece a could be easily pulled out from the cured mortar. The test piece a
Has a swollen water-absorbent resin layer formed on the surface thereof. Therefore, the width of the hole formed after the test piece a is pulled out is sufficiently larger than the width of the test piece a. Was. On the other hand, in order to pull out the test piece de from the hardened mortar, the test piece d and e required about four times the pulling load as compared with the test piece a. In addition, the blank test piece, even when a 55 kgf pull-out load is applied,
The mortar could not be pulled out from the cured product.

Therefore, by applying the dispersion mixture to the surface of the test piece, the adhesion between the test piece a and the cured mortar can be suppressed, and the workability can be improved. It was found that even if a water-resistant coating was formed on the surface of the sample, no problem was caused to the workability.

Example 4 A 33% by weight solution of an alkaline water-soluble resin in methyl alcohol prepared by the method described in Example 1 and the water-absorbent resin (average particle diameter 150 μm) used in Example 2 were used. Are mixed, pulverized and dispersed so that the weight ratio between the water-absorbent resin and the alkali-water-soluble resin in the dispersed mixed liquid is 1: 1 and the maximum pull-out strength is 0.003.
An anti-adhesion material 4 of 9 kg / cm ² was prepared. Also,
The conditions in which the amount of adhesion of the anti-adhesion material 4 to the H-section steel (the amount of dried coating film) was 50, 100, and 200 g / m ² were referred to as Condition 1, Condition 2, and Condition 3, respectively. Furthermore, the condition in which a water-resistant film was formed at 50 g / m ² on the coating film of Condition 2 was referred to as Condition 4. As the water-resistant coating, an alkali water-soluble resin prepared by the method described in Example 1 was used. In addition, only the alkali water-soluble resin is 100 g / m ^2.
The condition of application was set as a comparison condition, and the condition of no application (only H-section steel) was set as a blank condition.

H-100 mm × 100 mm (width), length of 1 m H-shaped steel (steel thickness: 10 mm) was evenly brushed with anti-adhesion material 4 under the above conditions under the above conditions, and dried overnight. A coating was formed. The coating film had sufficient adhesion to the H-section steel and did not easily peel off even when rubbed with an iron spatula or the like. The H-shaped steel applied under the condition 1 was designated as an H-shaped steel 1, and the others were similarly designated as an H-shaped steel 2, an H-shaped steel 3, and an H-shaped steel 4. The H-section steel applied under the conditions for comparison was defined as a H-section steel for comparison, and a blank H-section steel having only the H-section steel without any blank conditions was used.

Next, the above-mentioned H-section steels (H-section steels 1 to 4,
H-shaped steel for comparison and blank H-shaped steel in total (eight pieces) were respectively inserted into the center of a bottomed paper void tube (manufactured by Showa Marutsu, trade name: Sonovoid) having an inner diameter of 250 mm. The bottom of the void tube was closed by closing it with a plastic bag.

On the other hand, as a hydraulic composition, water, cement, clay, and bentonite were added at 52.6: 12.
A cement composition blended at a ratio of 2: 34: 1.2 (weight ratio) was prepared. And, the cement composition,
The inserted H-shaped steel (H-shaped steel 1 to 5, H-shaped steel for comparison, and a total of seven blanks) was cast into the void tube so as to fill 900 mm.

Thereafter, these cement compositions were cured.

After one week, the hardened body of the cement composition was fixed, and the H-shaped steel was pulled out from the hardened body. And
The pulling load (tensile force) required for the pulling operation was measured.

The pulling load when pulling out the H-section steel 1 is 230
kgf. The pulling load when pulling out the H-section steel 2 is 6
It was 8 kgf. The pulling load when pulling out the H-section steel 3 was 19 kgf. The pulling load when pulling out the H-section steel 4 was 60 kgf. The pulling load when pulling out the comparative H-section steel exceeded 300 kgf and exceeded the measurement limit. Pulling load when pulling out blank H-section steel is 300k
The measurement limit was exceeded at gf or more. The numerical value of the maximum pull-out strength includes the weight of the H-section steel.

Example 5 A water-absorbent resin was produced by crosslinking and copolymerizing sodium acrylate and acrylic acid under predetermined conditions. The average particle size of the water absorbent resin is 1
It was 00 μm. On the other hand, the alkali water-soluble resin used was the one prepared in Example 1.

The water absorbent resin 50 prepared as described above
The anti-adhesion composition 5 was prepared by mixing, pulverizing and dispersing 150 parts by weight of a 33 parts by weight methyl alcohol solution of an alkali water-soluble resin with parts by weight. Next, this dispersion-mixed liquid anti-adhesion composition 5 was wetted with a wet tensile strength of 31 kg / 25 mm.
Was uniformly applied to a sheet-like base material and dried to obtain a sheet-like anti-adhesion material 5. The weight ratio (water-absorbent resin / alkali-water-soluble resin) of the water-absorbent resin and the alkali-water-soluble resin of the sheet-shaped adhesion preventing material 5 is 1/1, and the dry adhesion amount of the water-absorbent resin and the alkali-water-soluble resin is 80g / m
^{And 2} .

Next, the sheet-form anti-adhesion material 5 is sewn together so that the application surface of the anti-adhesion composition is on the inside, so that the maximum pull-out strength of a width of 700 mm × a height of 1200 mm is 0.0035 kgf / cm ² . A bag-shaped adhesion preventing material 5 was produced.

H-100 × 100 H steel with a length of 1 m
The bag-like adhesion preventing material 5 was wrapped so as to be worn. At this time, the application surface is disposed inside the bag-shaped adhesion preventing material 5 on the H steel surface side.

On the other hand, a soil cement composition (hydraulic composition) was prepared by mixing water, cement, clay and bentonite in a weight ratio of 755: 175: 488: 18.

Next, after the soil cement composition was put into a container having a depth of 1 m, H wrapped with the bag-like adhesion preventing material 5 was used.
A section steel was driven into the soil cement composition.

After a lapse of 7 days, the H-shaped steel was drawn from the cured product of the soil cement composition using a drawing machine. The pulling load required for the pulling operation is 17 kgf,
H steel could be very easily extracted from the cured product of the soil cement composition.

[Example 6] Sewing was performed so that the application surface of the anti-adhesion composition was on the outside, and the maximum pull-out strength was 0.1%.
Example 5 Example 5 was repeated except that a bag-shaped anti-adhesion material 6 of 0047 kg / cm ² was prepared and arranged outside the bag-shaped anti-adhesion material 6 so that the application surface was in direct contact with the soil cement composition. The same operation was performed as the above operation. In addition, H-100x
When the bag-shaped anti-adhesive material 6 was wrapped around 100 m of 1-m long H steel, the sharp corners of the H-shaped steel were sometimes caught, but hardly damaged.

After 7 days, the pulling load required for the drawing operation was 24 kgf, and the H steel could be pulled out very easily from the cured product of the soil cement composition.

Comparative Example 1 0.12 mol% of N, N'-methylenebisacrylamide (based on sodium acrylate monomer) and 1.0 g / mol of sodium persulfate were added to a 75% aqueous solution of sodium hydroxide and neutralized sodium acrylate. (Sodium acrylate monomer) was dissolved to prepare a 40% by weight aqueous monomer solution.

A nonwoven fabric of polypropylene / polyethylene having a wet tensile strength of 2.4 kgf / 25 mm was immersed in this aqueous monomer solution, and the aqueous solution was impregnated. The impregnated material was heated to perform radical polymerization, thereby obtaining a comparative anti-adhesion material 1 in which 60 g / m ² of the water-absorbing resin was directly fixed to the base material without a bonding agent.

Next, the comparative anti-adhesion material 1 obtained by adhering the water-absorbent resin to the sheet-like base material without using a bonding agent was sewn to obtain a width of 700 mm × a height of 1200 mm.
A comparative bag-shaped anti-adhesion material 1 having a maximum pull-out strength of 0.010 kgf / cm ² was prepared.

H-100 × 100 H steel with a length of 1 m
When the comparative bag-shaped adhesion preventing material 1 was wrapped so as to be worn, a sharp corner of the H-shaped steel was caught and a part thereof was easily torn.

On the other hand, a soil cement composition (hydraulic composition) was prepared by mixing water, cement, clay and bentonite in a weight ratio of 755: 175: 488: 18.

Next, after the soil cement composition was put into a container having a depth of 1 m, the H-shaped steel wrapped with the comparative bag-shaped anti-adhesion preventive material 1 which had been partially damaged was driven into the soil cement composition. .

After a lapse of 7 days, the H-section steel was drawn out of the cured product of the soil cement composition using a drawing machine. The pulling load required for the pulling operation was as high as 127 kgf, and H steel could not be easily pulled out from the cured product of the soil cement composition.

[0151]

The anti-adhesion material according to claim 1 of the present invention is
As described above, at least a water-absorbing material and a bonding agent that adheres the water-absorbing material, and are interposed between the hydraulic composition and the support to increase the adhesive force between the cured body of the hydraulic composition and the support. The material to be reduced, the maximum pull-out strength is 0.019kg
f / cm ² or less.

Accordingly, when the support is pulled out from the cured product of the hydraulic composition, the swollen water-absorbing resin exerts a lubricating effect, so that the support becomes slippery. Therefore, since the labor (tensile force) in the operation of pulling out the support from the cured body of the hydraulic composition can be further reduced, the workability of the operation can be improved. On the other hand, when the cured body of the hydraulic composition is peeled from the support, the adhesion between the two can be suppressed by the layer of the swollen water-swellable resin, so that labor can be reduced,
The workability of the operation of peeling the cured body of the hydraulic composition from the support can be improved. In addition, by drying the water-absorbent resin, a gap can be formed between the cured body of the hydraulic composition and the support, so that the workability of the above-mentioned various operations can be further improved.

Further, by making the form of the anti-adhesive material into a sheet, a bag, or a tube, the place where the composition is applied at the construction site and the application work become unnecessary, and the workability of the worker can be greatly improved. Can be.

Further, in the case of a sheet-like (bag-like or cylindrical) anti-adhesion material, when selecting a sheet-like substrate on which an anti-adhesion composition comprising a water-absorbing material and an alkali-water-soluble resin is to be applied (applied), the strength must be selected. By selecting a strong (breakage-preventing) substrate, it is possible to prevent damage to the anti-adhesion material during construction and handling. This can prevent the adhesion between the support and the cured product of the hydraulic composition from deteriorating due to breakage, thereby greatly facilitating the separation of the two.

Therefore, according to the above configuration, it is possible to provide an anti-adhesion material which greatly suppresses the adhesion between the support and the cured product of the hydraulic composition, and makes it extremely easy to separate them. To play.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing a ground foundation structure as a structure according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a main part of the ground foundation structure.

FIG. 3 is a cross-sectional view schematically illustrating a ground foundation structure as a structure according to another embodiment of the present invention.

FIG. 4 is a sectional view schematically showing a ground foundation structure as a structure according to still another embodiment of the present invention.

5 (a) and 5 (b) are schematic perspective views showing a procedure for wrapping (covering) a support using an anti-adhesion material according to an embodiment of the present invention.

FIG. 6 (a) to (d) wrap (cover) a support using an anti-adhesion material according to another embodiment of the present invention.
It is a schematic perspective view which shows a procedure.

[Explanation of symbols]

 Reference Signs List 1 ground 2 cured body of hydraulic composition 2a pile head 3 support 4 anti-adhesion material 4a water-absorbent resin particles 4b alkaline water-soluble resin 13 tubular support 21 anti-adhesion material 22 support 30 anti-adhesion material

Continued on the front page (72) Inventor Yohei Murakami 5-8, Nishiobari-cho, Suita-shi, Osaka Nippon Shokubai Co., Ltd. (72) Inventor Akira Hattori 4-1-1, Koraibashi, Chuo-ku, Osaka-shi, Osaka Japan F term in catalyst (reference) 2D050 AA13 DA01 DA10

Claims (3)

[Claims] 1. A material comprising at least a water-absorbing material and a bonding agent, which is interposed between a hydraulic composition and a support to reduce the adhesive strength between the cured product of the hydraulic composition and the support. An anti-adhesion material having a maximum pull-out strength of 0.019 kgf / cm ² or less. 2. The anti-adhesion material according to claim 1, wherein the water-absorbing material is a water-absorbing resin. 3. The anti-adhesion material according to claim 1, wherein the bonding agent is an alkali water-soluble resin.