JP2000054372A - Covering material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a covering material, by which the workability of works, in which the core material (a temporarily buried article) of H-steel, etc., can be improved. SOLUTION: A temporarily buried article is covered under a non-contact state by using the covering material, in which a resin layer containing a water- soluble resin is formed on a sheet-shaped base material, or the covering material comprising the sheet-shaped base material, a water-absorbing material such as a water swelling resin and a cementing material bonding the water-absorbing material onto the sheet-shaped base material. In a covering method, the temporarily buried article 2 is hung up by using a crane 6 while a cord 3 passed along a block 5 mounted at the front end section of the crane 6 is set up to the covering material 1, the covering material 1 formed in a baggy shape or a cylindrical shape is inserted into the temporarily buried article 2 so as to be put on from a lower section by pulling the cord 3 by an operator 4 in the covering material 1 formed in the baggy shape or the cylindrical shape, and the covering material 1 is drawn up and fitted and fixed by further pulling the cord 3 by the operator 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a covering material for covering a temporary buried object. More specifically, the present invention provides, for example, a structure that is configured to be able to more easily pull out a temporary buried object buried in soil, or at least a temporary buried object and a cured product of a hydraulic composition. In, in order to suppress the adhesion of both, so that the temporary embedded material can be more easily pulled out from the cured product of the hydraulic composition,
The present invention relates to a covering material for covering the temporary buried object.

[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 a construction work in a construction field and a civil engineering field, for example, an H-shaped steel is loosely inserted into an excavation hole. Injecting and hardening a hydraulic composition such as cement milk or ready-mixed concrete around the H-shaped steel, or embedding (punching), for example, an H-shaped steel as a core material in the hydraulic composition injected into the borehole. Thereafter, the hydraulic composition is cured. It is desired that after the hardening of the hydraulic composition is completed, the H-shaped steel is pulled out of the hardened material and removed so as not to hinder the development of the underground later in the year.

[0003] However, the H-type steel and the cured product of the hydraulic composition are firmly adhered to each other, and in order to remove the H-type steel after the completion of the construction, the operation of pulling out the H-shaped steel from the cured product requires an adhesive strength ( Since considerable labor (tensile force) is required to overcome the adhesive strength, equipment, cost, and days are required.

Therefore, in order to easily perform the above-mentioned drawing operation, conventionally, i) a method of applying a lubricating oil such as wax or grease to the surface of the H-shaped steel in advance, or bonding a water-absorbing resin to the surface of the H-shaped steel. Method using an agent, or i
i) A method of attaching a lubricant to the surface of the H-section steel,
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 Patent Application No. -58715 proposes to use a core material drawing surface treatment agent comprising a water-absorbing resin and a spreading agent such as a polyester resin, a vinyl resin, an acrylic resin, and a urethane resin. . In addition, for example,
No. 165615 discloses a method for reducing the 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. Proposed.

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, Japanese Patent Application Laid-Open No. 7-247549 discloses a bag-shaped polymer sheet in which a water-absorbent resin is directly fixed to a base material such as a woven or nonwoven fabric. A method of reducing the frictional resistance when the temporary buried object is pulled out by coating the temporary buried object with the above lubricant has been proposed.

[0008]

However, the spreading agent contained in the surface treatment agent 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 property with respect to 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 conventional surface treatment agent and the water-swellable film described above, because 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 absorption properties (performance). Furthermore, the water absorbing resin contained in the above-mentioned conventional surface treatment agent and water-swellable film has poor swellability with respect to cement water. In addition, a coating film formed by applying a surface treatment agent 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 the change. In addition, when a surface treatment agent is applied 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 surface treatment agent.

Further, the lubricant described in JP-A-6-185054 and the lubricating tape described in JP-A-62-174418 are capable of absorbing the water-absorbing swelling of super-absorbent fibers and water-absorbent resin with respect to cement water. Therefore, the improvement of the work of pulling out the temporary buried object is insufficient. In addition, since the surface of the temporary buried material (steel material) is usually rusted or stained, it is difficult to apply a lubricating tape, and at the time of construction, it comes in contact with cement water, unexpected water wetting and rainfall Also, the water-absorbent resin easily falls off. Therefore, the lubricating tape cannot exert its effect. In addition, when temporary buried objects are piled up on the ground, if the temporary buried objects become wet due to rainfall or the like, it becomes impossible to apply a lubricating tape. On the other hand, also with respect to the above-mentioned lubricant, the surface of the temporary buried object (steel material) to which the lubricant is to be adhered usually has rust, dirt, etc. attached thereto, so that it is difficult for the lubricant to be attached. This introduces problems.

Further, the above-mentioned conventional surface treating agent, water-swellable film, lubricant and lubricating tape are directly fixed to a core material such as H-shaped steel. Therefore, these surface treatment agents and the like can only come into contact with the cement water on one side (surface side) only, so that the water-absorbing resin or super-absorbent fiber can sufficiently exhibit its water-absorbing properties (performance). Therefore, it is difficult to pull out the core material from the cured product of the hydraulic composition.

Therefore, the conventional surface treating agents, water-swellable films, lubricants, and lubricating tapes do not provide satisfactory performance.
There is a problem that the effect of facilitating the operation of pulling out a core material such as an H-shaped steel is poor.

The bag-shaped lubricant described in Japanese Patent Application Laid-Open No. 7-247549 has a water-absorbing resin directly and firmly fixed to a substrate. As the lubricating material, a thin base material that is flexible and has a weak fiber regulation is used. This is because, when a base material having a large thickness and high strength is used, the productivity of a product (lubricating material) is extremely reduced. This is because the quality of the product (lubricating material) is deteriorated because of the tendency to occur. Therefore, the conventional bag-shaped lubricating material using a low-strength base material is damaged by an external force applied when the core material is coated or when the core material is embedded (punched) into the injected hydraulic composition. There is a possibility that. For this reason, it may not be possible to sufficiently prevent the core material from sticking to the cured product of the hydraulic composition.

Therefore, a coating material that can facilitate the operation of pulling out a core material such as an H-shaped steel, that is, without causing the above-mentioned various problems at the time of applying the core material,
There is a need for a coating material that can more easily and reliably extract the core material from a cured product of the hydraulic composition. still,
At present, drawability and workability are inadequate, and there are problems such as the necessity of urgently bringing in a larger drawing device than planned during the drawing operation, but there is no alternative technology. Lubricating oil directly on the surface of the core material
Only a method of applying and a method of coating a core material with a polyvinyl chloride sheet having lubricity have been implemented.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a coating material capable of improving an operation of extracting a core material (temporary buried material) such as an H-shaped steel. Is to do.

[0015]

Means for Solving the Problems The present inventors diligently studied a coating material to solve the above-mentioned conventional problems. As a result, a coating material in which a resin layer containing a water-soluble resin is formed on a sheet-like substrate, or a sheet-like substrate,
By covering the temporary buried material with a covering material containing a water-absorbing material such as a water-swellable resin and a bonding agent for attaching the water-absorbing material to the sheet-like substrate, for example, the temporary buried material and the hydraulic composition The present inventors have found that it is possible to suppress the adhesion to the cured product of the present invention, and to improve the workability of the operation of pulling out the temporary embedded material from the cured product of the hydraulic composition, thereby completing the present invention.

That is, in order to solve the above-mentioned problems, the coating material according to the first aspect of the present invention is a coating material for coating a temporarily buried object in a non-adhered state. Characterized in that a resin layer containing is formed.

According to the above arrangement, for example, when the temporary buried material is covered with the coating material so as to pull out the temporary buried material from the cured product of the hydraulic composition, the water contained in the hydraulic composition can be removed. By dissolving the water-soluble resin, an easily peelable layer can be formed between the sheet-like base material and the cured product of the hydraulic composition, so that the work of pulling out the temporary embedded material from the cured product of the hydraulic composition is performed. Can be reduced, and the workability of the work can be improved. Also,
Since the coating material is not directly adhered to the temporary buried object, it can be brought into contact with the water contained in the hydraulic composition on both surfaces (the outer surface and the inner surface) of the coating material, It becomes easier to form an easily peelable layer between the sheet-like substrate and the cured product of the hydraulic composition. Further, since the resin layer is formed on a sheet-like base material such as a woven cloth which is soft and permeable to a resin solution, the resin layer is firmly adhered to the sheet-like base material. When the resin layer further contains a water-absorbing material, it is possible to prevent the water-absorbing material from separating before or during construction. Therefore, according to the above configuration, it is possible to provide a covering material that can improve the operation of pulling out the temporary buried object.

According to a second aspect of the present invention, there is provided a covering material for covering a temporarily buried object in a non-adhered state in order to solve the above-mentioned problems. And a bonding agent for adhering the water-absorbing material to the sheet-like base material.

According to the above arrangement, for example, when the temporary buried object is covered with the coating material so as to pull out the temporary buried object from the cured product of the hydraulic composition, the temporary buried object and the hydraulic composition are not covered. During this time, a layer of the water-absorbing material swelled by absorbing water is formed. In other words, a layer of the swollen water-absorbing material can be formed between the temporarily embedded object and the cured product of the hydraulic composition,
The adhesion between the two can be further suppressed. Thus, when the temporary embedded object is pulled out from the cured product of the hydraulic composition, the swollen water-absorbing material exerts a lubricating effect, so that the temporary embedded object becomes slippery. Therefore, the labor (tensile force) in the operation of pulling out the temporarily embedded object from the cured product of the hydraulic composition can be further reduced, and the workability of the operation can be improved. Further, by drying the water absorbing material, a gap can be formed between the temporarily embedded object and the cured product of the hydraulic composition, so that the workability of the above operation can be further improved.

According to a third aspect of the present invention, there is provided a coating material according to the first or second aspect, wherein the water-soluble resin or the bonding agent is the same as the sheet-like base material. It is characterized in that the resin is a water-soluble resin having a falling rate of 50% or less.

According to the above configuration, the water-soluble resin (or bonding agent) can be further prevented from dropping from the sheet-like base material before or during the construction, so that the sheet-like base material and the hydraulic A sufficient easy peeling layer can be formed between the composition and the cured product. Therefore, labor (tensile force) in the work of pulling out the temporary buried material from the cured product of the hydraulic composition
Can be reduced, and the workability of the work can be improved.

According to a fourth aspect of the present invention, there is provided the sheet-like flexible material, wherein the sheet-like base material comprises at least a water-soluble resin and a water-absorbing material. It is characterized in that a resin layer having a falling rate from a material of 50% or less is formed.

According to the above configuration, for example, a sheet-like flexible material suitable for coating various articles can be provided.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Temporary buried objects to be covered with the coating material according to the present invention are buried objects that are supposed to be buried after use or when they are no longer needed, or buried objects that are preferably removed. It is not particularly limited as long as it is a material, and in the following description, an example of the temporary buried material used for a structure composed of at least a temporary buried material and a cured product of the hydraulic composition is used. I will list it. That is, in the following description, a covering material for covering the temporary buried object used in the structure will be described as an example.

Examples of the above-mentioned structure include ground foundation structures such as earth retaining walls and foundations in foundation work in the fields of construction and civil engineering. Examples of the hydraulic composition constituting the structure include various concretes such as soil cement, various mortars, and the like, but are not particularly limited, and are generally used for foundation work in the construction field and the civil engineering field. Any hydraulic composition that is used when constructing a ground foundation structure such as a retaining wall or a base may be used. The hydraulic composition becomes a cured product by curing. The types and combinations of cement, admixtures, admixtures, aggregates, reinforcing materials, and the like contained in the hydraulic composition, that is, the composition of the hydraulic composition are not particularly limited.

Specific examples of the temporary buried objects constituting the structure include H-shaped steel, I-shaped steel, iron columns, concrete piles, poles, tubular piles (hollow piles), and long plate-shaped piles. A certain steel sheet pile (sheet pile), a corrugated sheet, or the like may be used, but it is not particularly limited. Temporary buried objects are generally used when constructing ground foundation structures such as earth retaining walls and foundations in foundation work in the construction field and civil engineering field,
In addition, any embedded object (core material) that needs to be extracted from the cured product of the hydraulic composition after use or an embedded object that is desirably extracted may be used. In addition, the shape, length,
The material and the like are not particularly limited.

The sheet-like base material constituting the covering material (sheet-like flexible material) according to the present invention can be formed by various external forces applied when the ground substructure is constructed, for example, a temporary embedded material or a hydraulic composition. Tensile force and shear force caused by the application of weight; impact force and tensile force generated when burying temporary buried objects;
The material is not particularly limited as long as it is made of a material having a strength that can withstand a frictional force between the hydraulic composition and the like, that is, a strength that does not break even when the external force is applied.

As the material of the sheet-like substrate, 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 .; fabrics such as flat yarn fiber fabric, cotton fabric, hemp fabric, band-shaped fabric, band cord, synthetic resin fabric made of polypropylene, etc. Kinds of mixed fabrics, such as woven fabrics obtained by blending polyester fibers and cotton fibers; closed cells and the like inside a material such as polystyrene, polyethylene, polypropylene, vinyl chloride resin, urethane resin, phenol resin, and rubber foam. 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 or poly Plastic sheets made of propylene, polyethylene terephthalate, polyamide (nylon), vinyl chloride resin, acrylic resin, etc., leather sheets and wood sheets, waterproofed paper sheets, natural sheets such as cardboard sheets, aluminum, iron, copper, Sheets such as metal sheets made of silver, etc., alloy sheets made of stainless steel, etc., 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).

Of the above-listed materials, they are excellent in water permeability and workability and are inexpensive, and are inexpensive. And blended fabrics are particularly preferred.

[0030] Of the above-listed materials, for example, a material having no water permeability, such as a sheet, may be provided with a cut or a hole, for example, as necessary. In this case, the shape, size, number, and formation position of the cuts and holes are
It is not particularly limited, and can be appropriately set within a range that can maintain the strength that the sheet-shaped substrate does not break even when the external force is applied.

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. In addition, 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.

[0032] 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 of the sheet-like substrate is not particularly limited, but is preferably 1 kgf / 2.5 cm or more, more preferably 10 kgf / 2.5 cm or more, and more preferably 30 kgf / 2. It is particularly preferred that it is not less than 0.5 cm. Tensile strength is 1kgf / 2.5
cm or more, the sheet-like substrate can maintain the strength that does not break even when the external force is applied. When the tensile strength of the sheet-like substrate is less than 1 kgf / 2.5 cm,
It is easy to tear or tear when external force is applied.

The tensile strength is 2.5 cm in width and 2 in length.
After cutting to a size of 0 cm, a test piece (sheet-like base material) immersed in ion-exchanged water for 30 minutes and sufficiently wetted was used, and a tensile test method (tensile strength) of JIS L 1096 (general fabric test method) was used. ), A pulling speed of 20 mm / min and a gripping distance of 10 c
The measurement was performed under the condition of m. It can be determined that the larger the measured value (unit: kgf / 2.5 cm) obtained by the tester, the higher the tensile strength of the sheet-shaped substrate.

The sheet-like base material, that is, the covering material may be formed in a shape and a size that can cover the temporary buried material. More preferably, it is formed in a bag shape or a tubular shape that can be inserted. By forming the sheet-like base material (that is, the covering material) in a bag shape or a tubular shape, a large and heavy temporary buried object can be more easily and quickly covered, so that the work at the work site can be performed. Properties can be further improved.

The bonding agent contained in the coating material according to the present invention is not particularly limited as long as it is a substance capable of adhering the water-absorbing material to the sheet-like substrate. Examples of the bonding agent include a water-soluble resin, a water-dispersed resin (emulsion), a solvent-based resin, a hot melt resin, and an adhesive.

As the above water-soluble resin, specifically,
For example, starch paste, soluble starch, modified starch, dextrin, methylcellulose, partial methylcellulose, carboxymethylcellulose; polyvinyl alcohol derivatives such as polyvinyl alcohol, polyvinyl butyral, polyvinyl formal, and polyvinyl acetate;
Polyacrylic acid; and the like, but are not particularly limited thereto. One of these water-soluble resins may be used alone, or two or more thereof may be used in combination. When the above water-soluble resin is used in combination with a water-absorbing material such as a water-swellable resin, the water-soluble resin functions as a binder (bonding agent) for attaching the water-absorbing material to the sheet-like substrate, but is not used in combination with the water-absorbing material. In the above, a resin layer is formed on the surface of the sheet-like substrate.

Specific examples of the above-mentioned water-dispersed resin include natural rubber, synthetic rubber, vinyl acetate resin, acrylate copolymer, polymethyl methacrylate, and styrene-butyl acrylate copolymer. Although it is mentioned, it is not particularly limited. The water-dispersed resin is obtained by dispersing or suspending these rubbers and synthetic resins in water. One of these water-dispersed resins may be used alone, or two or more thereof may be used in combination.

As the solvent-based resin, specifically,
For example, a polyester resin, a vinyl resin, an acrylic resin, a urethane resin, and the like can be given, but are not particularly limited. Solvent-based resin, these synthetic resins,
It is obtained by dissolving or dispersing in a solvent. These solvent-based resins may be used alone,
Two or more types may be used in combination. Further, as the solvent,
Specific examples include, but are not limited to, methyl alcohol, ethyl alcohol, ethyl acetate, methyl ethyl ketone, toluene, and hexane. These solvents may be used alone,
Two or more types may be used in combination.

As the above-mentioned hot melt resin, specifically, for example, ethylene-vinyl acetate copolymer (EV
A), ethylene-ethyl acrylate copolymer (EE
A), polyethylene, polyamide, polyester, atactic polypropylene and the like, but are not particularly limited. One of these hot melt resins may be used alone, or two or more thereof may be used in combination.

Specific examples of the pressure-sensitive adhesive include an acrylic pressure-sensitive adhesive, a polyisobutylene pressure-sensitive adhesive, and an SB pressure-sensitive adhesive.
Examples thereof include an R pressure-sensitive adhesive and a butyl rubber pressure-sensitive adhesive, but are not particularly limited. These adhesives may be used alone or in combination of two or more.

Since the water-soluble resin of the above-mentioned bonding agents is dissolved in water, there is no possibility that the water-absorbing material absorbs water and swells when the water-absorbing material swells. In addition, among the above water-soluble resins, polyvinyl alcohol is more excellent in performance of preventing falling off from a sheet-like substrate such as a water-absorbing material (described later), and more specifically, the following falling rate is 50%. It is particularly preferable because it can be suppressed to the following.

In the present invention, the detachment rate from the sheet-like substrate is a value calculated by the following method. That is, the falling-off rate (%) means that the coating material according to the present invention is obtained from the sheet-like base material based on the weight change between before and after immersion in ion-exchanged water and after immersion for 5 minutes (after drying). The amount of the dropped polymer (the combination of the bonding agent and the water-absorbing material) was measured, and the amount of the dropped polymer (g) was immersed in ion-exchanged water. Is a value calculated by dividing by. That is, the shedding rate (%) = [(weight of coating material before immersion (g)-weight of coating material after immersion (g)) / (weight of coating material before immersion (g)-sheet shape Weight of substrate (g)] × 100.

When the total amount of the polymer (g) is unknown, the measurement was carried out in the case where the bonding agent was a water-soluble resin, by adding a 0.4% by weight aqueous solution of sodium hydroxide at 40 ° C. until the adhered polymer almost dropped off. It may be immersed (for example, immersed for 24 hours), dried, and the change in weight before and after immersion may be defined as the total polymer amount (g). Also, when the bonding agent is a hydrophobic resin,
The resin may be immersed in an organic solvent capable of dissolving the resin, and the change in weight may be regarded as the total polymer amount (g) as described above.

When a temporary buried object is driven into the excavation hole into which the hydraulic composition has been injected (driving operation), a frictional force is applied to the coating material. If this driving is performed smoothly, it will be completed in a short time (about 1 minute), so that there is no particular problem. However, when the temporary buried object is long, the driving time is long and the hydraulic composition contains Since the pressure of the muddy water increases in the deep part to increase the frictional force, the bonding agent or the water-absorbing material adhering to the sheet-like base material is liable to fall off, and the pullability may be extremely reduced. Similarly, when the driving time is prolonged due to re-injection or the like, it is easy to fall off and the pull-out property may be reduced. Therefore, the shedding rate is preferably 50% or less, more preferably 30% or less. If the falling rate exceeds 50%, the pullability of the temporary buried object may be reduced as described above.

Further, in order to impart flexibility to the covering material or the sheet-like flexible material and to improve handleability, the water-soluble resin or the bonding agent may contain a plasticizer such as a polyhydric alcohol. More desirable.

The water-absorbing material according to the present invention, that is, the water-absorbing material adhered to the sheet-like substrate by the above-mentioned bonding agent may be made of any material capable of absorbing water, and is not particularly limited. Is a water-swellable resin, a water-absorbent sheet such as a woven or nonwoven fabric to which the water-swellable resin is adhered, a water-absorbent fiber, or a porous material such as a sponge or felt that can absorb and hold water twice or more its own weight. Body, etc. are preferred. Among the water absorbing materials exemplified above, a water-swellable resin is particularly preferable.

The above water-swellable resin is not particularly limited as long as it is a resin which 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. A resin having a water absorption ratio of 10 times or more is more preferable. Specific examples of the water-swellable resin include, for example, a crosslinked poly (meth) acrylic acid, a crosslinked poly (meth) acrylate, a crosslinked poly (meth) acrylate having a sulfonic acid group, and a poly (meth) acrylate. Crosslinked poly (meth) acrylate having an oxyalkylene group, crosslinked poly (meth) acrylamide, crosslinked copolymer of (meth) acrylate and (meth) acrylamide, hydroxyalkyl (meth) acrylate and ( Cross-linked copolymer with meth) acrylate, cross-linked polydioxolane, cross-linked polyethylene oxide, cross-linked polyvinyl pyrrolidone, cross-linked sulfonated polystyrene, cross-linked polyvinyl pyridine, saponified starch-poly (meth) acrylonitrile graft copolymer, Starch-poly (meth) acrylic acid (salt)
Graft crosslinked copolymer, reaction product of polyvinyl alcohol and maleic anhydride (salt), crosslinked polyvinyl alcohol sulfonate, polyvinyl alcohol-acrylic acid graft copolymer, polyisobutylene maleic acid (salt)
Crosslinked polymers and the like can be mentioned. One of these water-swellable 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-swellable resin to such an extent that the various properties (water absorption ratio, etc.) of the water-swellable resin are not impaired.

Among the water swellable resins exemplified above, a water swellable resin having a nonionic group and / or a sulfonic acid (salt) group is more preferable, and a water swellable resin having an amide group or a hydroxyalkyl group is more preferable. . Examples of the water-swellable resin include a cross-linked copolymer of (meth) acrylate and (meth) acrylamide, and a cross-linked copolymer of hydroxyalkyl (meth) acrylate and (meth) acrylate. No. Further, among the water swellable resins exemplified above, a water swellable resin having a polyoxyalkylene group is particularly preferable. As the water-swellable resin,
For example, a crosslinked copolymer of a (meth) acrylic acid ester having a methoxypolyoxyalkylene group and a (meth) acrylic acid salt may be mentioned. The water-swellable resin having a methoxypolyoxyalkylene group is particularly excellent in swellability in alkaline water for a long period of time.
Therefore, by using the water-swellable resin, the operation of pulling out the temporarily buried object can be performed extremely easily.

The term "water exhibiting alkalinity" (hereinafter referred to as "alkali water") refers to water such as concrete water contained in a hydraulic composition such as concrete or mortar. Further, the pH of the alkaline water is not particularly limited.

Further, as the water-swellable 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. Can be used. A water-swellable resin obtained by (co) polymerizing an ethylenically unsaturated monomer is more excellent in swellability in water and is generally inexpensive. Therefore, by using the water-swellable resin, the operation of pulling out the temporarily buried object can be performed extremely easily and more economically. In addition, the above-mentioned crosslinking agent is not particularly limited. A water-swellable resin can also be formed by adding a crosslinking agent to a linear polymer and crosslinking the polymer, or by irradiating an electron beam to perform crosslinking.

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, an ethylenically unsaturated monomer having a nonionic group and / or a sulfonic acid (salt) group is more preferable. Examples of the monomer include 2- (meth) acrylamide-2
-Methylpropanesulfonic acid, 2- (meth) acryloylethanesulfonic acid, 2- (meth) acryloylpropanesulfonic acid, (meth) acrylamide, hydroxyalkyl (meth) acrylate, methoxypolyethylene glycol mono (meth) acrylate and the like. . Further, an ethylenically unsaturated monomer having a polyoxyalkylene group is particularly preferred. A water-swellable 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-swellable resin, the operation of pulling out the temporarily buried object can be performed extremely easily.

When two or more ethylenically unsaturated monomers are used in combination as the monomer component, the ethylene component having a nonionic group and / or a sulfonic acid (salt) group in the monomer component is used. The ratio of the unsaturated monomer is 1
%, More preferably at least 10% by weight. When the above ratio is less than 1% by weight, even when a water-swellable resin obtained by polymerizing the monomer component is used, the workability of the operation of pulling out the temporary buried material can be further improved. It may disappear.

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

By polymerizing the above monomer components,
A water-swellable resin is obtained. The method for polymerizing the monomer components, that is, the method for producing the water-swellable resin, is not particularly limited. The average molecular weight and shape of the water-swellable resin, the average particle size, etc., the composition of the hydraulic composition and the pH of alkaline water,
The combination with the sheet-like base material 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 still more preferably 150 μm or less. It is more desirable to use a water-swellable resin. By using the water-swellable resin having the average particle size, for example, the dispersibility or the mixing property of the water-swellable resin in a resin solution (described later) is improved, so that the handleability is further improved and the sheet-like shape is further improved. A water-swellable resin layer attached with a bonding agent can be easily formed on the surface of the base material. Further, the amount of the water-swellable resin adhered to the sheet-shaped substrate per unit area can be increased in a uniform state.

In the coating material according to the present invention, since the water-absorbing material is attached to the sheet-like substrate via the bonding agent,
A layer of a water-absorbing material swelled by absorbing water is formed between the sheet-like substrate and the cured product of the hydraulic composition. That is, since a layer of the swollen water-absorbing material can be formed between the temporarily embedded material and the cured product of the hydraulic composition, the adhesion between the two can be further suppressed. Thus, when the temporary embedded object is pulled out from the cured product of the hydraulic composition, the swollen water-absorbing material exerts a lubricating effect, so that the temporary embedded object becomes slippery. Therefore, the labor (tensile force) in the operation of pulling out the temporarily embedded object from the cured product of the hydraulic composition can be further reduced, and the workability of the operation can be improved. Furthermore, by drying the water absorbing material,
Since a gap can be formed between the temporarily embedded object and the cured product of the hydraulic composition, the workability of the above operation can be further improved.

For example, when a water-soluble resin is used as the bonding agent and a water-swellable resin is used as the water-absorbing material, the ratio between the two, that is, the water-soluble resin to be attached to the sheet-like substrate and the water-swellable resin The ratio of and may be set according to the composition and combination of the two, the working environment, etc.
Although not particularly limited, the weight ratio is from 1/99 to 9
It is more preferably in the range of 9/1, and 10/90 to 90/1.
0 is more preferable, and it is 25 / 75-75 / 25.
Is particularly preferred.

The adhesion amount of the water-soluble resin and the water-swellable resin per unit area of the sheet-shaped substrate may be set according to the composition and combination of the two and the working environment, and is not particularly limited. No, but 1 g / m ² -1
It is more preferably within the range of 000 g / m ² and 10 g / m ^2.
m ^{2 to} 5,000 g / m ² is more preferable,
In the range of 20g / m ² ~1,000g / m ² it is particularly preferred. The ratio of the water-soluble resin and the water-swellable resin to 100 parts by weight of the sheet-like substrate is 1 part by weight to 10,000 parts by weight.
It is more preferably in the range of 0 parts by weight, and 10 parts by weight to 1,0 parts by weight.
The content is more preferably in the range of 00 parts by weight, and more preferably 20 to 5 parts by weight.
Particularly preferred is a range of 00 parts by weight.

When a bonding agent other than a water-soluble resin is used, the ratio of the bonding agent to the water-swellable resin, or the amount of the bonding agent and the water-swellable resin adhered per unit area of the sheet-like base material is as follows. What is necessary is just to set according to the composition and combination of both, work environment, etc., and it is not specifically limited.

The method for attaching the water-absorbing material to the surface of the sheet-like substrate via a bonding agent is not particularly limited,
Specifically, for example, a method in which a dispersion obtained by dispersing a bonding agent and a water-swellable resin in a dispersion medium such as an organic solvent or water is sprayed (sprayed) on the sheet-like substrate surface; A method of coating or using a roller; a method of impregnating the sheet-like substrate with the above-described dispersion may be employed. Alternatively, after a solution or dispersion containing a bonding agent is sprayed or applied to the surface of the sheet-like substrate, a water-swellable resin is evenly spread over the surface, and the solution or dispersion is further sprayed or applied thereon. And the like. The dispersion or the like applied to the sheet-like substrate may be dried as necessary. Thereby, the water-swellable resin is attached to the sheet-like substrate surface (outer surface and / or inner surface) via the bonding agent. That is, a layer of the water-swellable resin is formed. When a resin layer containing a water-soluble resin is formed on the surface of the sheet-like base material, the step of dispersing the water-swellable resin and the step of spraying the water-swellable resin in the above method may be omitted. When a water-absorbing material other than the water-swellable resin is used, a method according to the above method may be employed.

The method for preparing the solution or dispersion containing the bonding agent and the water-swellable resin is not particularly limited. 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; ethylene glycol;
Polyhydric alcohols and derivatives thereof, such as ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, and polypropylene glycol monomethyl ether acetate; and the like, but are not particularly limited. It is sufficient that the thickness of the layer containing the water-swellable resin is about 10 μm, but it may be set according to the particle size of the water-swellable resin and is not particularly limited.

The sheet-like base material, that is, the covering material, contains a layer of a water-absorbing material such as the above-mentioned water-swellable resin or a water-soluble resin on the outer surface in a state of covering the temporary buried material. More preferably, a resin layer is formed. Thereby, the work of pulling out the temporary buried object can be performed more easily, and since the water-soluble resin dissolved in the alkaline water is less likely to adhere to the temporary buried object, the surface of the pulled out temporary buried object is cleaned. And it can be easily reused (recycled).

Further, when a water-soluble resin is used as the bonding agent, if necessary, a layer containing the water-soluble resin (resin layer) may be used to prevent the water-soluble resin from being dissolved by rain or the like. A water-resistant coating made of a water-resistance imparting agent can be formed (top-coated) on the surface.

Examples of the above-mentioned water resistance imparting agent include a conventionally known water repellent such as wax, and an alkali-soluble resin which dissolves in contact with an alkaline liquid. The selection may be made in consideration of a combination of the above, and is not particularly limited. The method of forming the water-resistant coating is not particularly limited, but specifically, for example, a dispersion obtained by dispersing a water-resistance imparting agent in a dispersion medium such as an organic solvent or water is applied to a resin layer. A method of spraying (spraying) a surface; a method of applying a dispersion liquid by brushing or using a roller; a method of spraying or applying a melt of a water resistance imparting agent; The dispersion or the like applied to the surface of the resin layer may be dried if necessary. Thereby, a water-resistant coating is formed on the surface of the resin layer. It is sufficient that the thickness of the water-resistant coating is about 50 μm, but it is not particularly limited. In addition, for example, when forming a water-resistant coating having a thickness of 50 μm, the application amount of the water-resistance imparting agent may be about 50 g / m ² .
There is no particular limitation.

By forming a water-resistant coating on the surface of the resin layer containing the water-soluble resin, it is possible to prevent the water-soluble resin from being dissolved even when rain is applied. Therefore, performance is not impaired even during rainfall during operation. Also,
When constructing the structure, the temporary buried object can be covered with the covering material at the work site.For example, the temporary buried object is covered with the covering material in advance, and the covered temporary buried object is worked. It can also be piled up on site. Therefore, there is no need to cover the temporary buried object with a waterproof sheet or to store it in an indoor material yard or the like, so that the temporary buried object can be stored simply and inexpensively. That is, simplification and rationalization of the work can be appropriately achieved according to the situation of the work site, so that the structure can be quickly constructed.

In the state where the temporary buried object is covered with the covering material, the temporary buried object and the covering material are in contact with each other but are not fixed. That is, the coating material according to the present invention is a non-adhesive (non-fixed) coating material. Therefore, a gap is formed between the temporary buried material and the coating material, into which the alkaline water can infiltrate. Therefore, the water-swelling properties of the water-swellable resin are further improved, and the adhesion between the two is further suppressed. can do. Then, the work of pulling out the temporarily buried object can be performed extremely easily by the synergistic effect with the lubricating effect by the swollen water-swellable resin.

When the temporary buried object is covered with the covering material, it is desirable to use one covering material for one temporary buried object. More than one coating can be used. Accordingly, as a method of covering the temporary buried object with the covering material, for example, a method of sandwiching the temporary buried object between two sheet-shaped covering materials may be employed. In the present invention, "coating"
Does not necessarily mean that the temporary buried object is hidden by the covering material so that the temporary buried object can be easily pulled out from the cured product of the hydraulic composition, that is, the adhesion between the two is suppressed. It shows that the temporary buried object is covered with the covering material to the extent that it can be performed.

As a method of covering the temporary buried object with the coating material, specifically, for example, a method of covering the temporary buried material with a bag-shaped or tubular-shaped coating material, A method of inserting into a covering material formed in a shape, a method of wrapping a temporarily embedded object with a covering material formed in a sheet shape, and the like can be adopted, but are not particularly limited.

When covering the temporary buried object with the covering material, it is more preferable to fix the covering material to the temporary buried object using a fixing jig. This makes it possible to cover the temporary buried object with the covering material along its shape, and it is possible to more effectively suppress the contact between the temporary buried object and the hydraulic composition. It is possible to improve the driving accuracy when driving the object.

Examples of the method of forming the covering material in a bag shape or a tubular shape include, for example, a method of bonding using an adhesive, a method of fusing by heat sealing, a method of stitching, a wire and a string. Various methods, such as a method of binding with, etc., can be adopted, but are not particularly limited. In addition, the packaging style of the covering material is not particularly limited, but a state of being wound up in a roll shape (FIG. 1) or a state of being folded in a bellows shape is preferable from the viewpoint of handling and workability. Is more preferable.

The time when the temporary buried object is covered with the covering material is not particularly limited, and may be an appropriate time before the temporary buried object is carried into the work site. It may be an appropriate time while storing
It may be an appropriate time before the work for embedding the temporary buried object starts. That is, the temporary buried object may be covered with the covering material at the time of burying. When using a covering material formed in a bag shape or a tubular shape, the covering material may be formed in these shapes at the time of embedding.

As a method of covering the temporary buried object with the covering material, more specifically, for example, as shown in FIG. The string 3 passed through the pulley 5 provided at the tip of the is attached to the covering material 1, and then the covering material 1 formed in a bag shape or a tubular shape is pulled downward by, for example, the worker 4 pulling the cord 3. After inserting into the temporary buried object 2 so that the covering material 1 can be put on, as shown in FIG. After inserting the covering material formed in a cylindrical shape from above into the temporary buried object and fixing the upper end, the temporary buried object is lifted using a crane, and then the string attached to the lower end of the covering material By an operator pulling the A method of pulling down and mounting the covering material: After placing the covering material formed in a bag or a tube shape on the ground or the like, inserting a temporary buried material into the covering material, and then pulling up the covering material, mounting and fixing. After placing the temporary buried object on the ground or the like, inserting a bag-shaped or tubular covering material into the temporary buried object, then lifting the temporary buried object and pulling up the covering material to mount the temporary buried object. Fixing method; FIG.
(A) As shown in FIG.
After placing the temporary buried object 2 on the crane 6 or the like,
As shown in FIGS. 2B and 2C, the covering material 10 wraps the temporary buried object 2 and then, as shown in FIG.
A method of fixing the covering material 10 using the fixing jigs 11; a method of sandwiching and fixing the temporary buried material between the covering materials folded in a bellows shape; and attaching both ends of the covering material to the upper and lower portions of the temporary buried material. A method of fixing; a method of fixing both ends of the covering material to the upper and lower portions of the temporary buried object, and fixing a central portion of the covering material using a wire (number line), a string, a belt, a gum tape, or the like; A method in which a part of the covering material is fixed to the upper part and the remaining part of the covering material is dropped along the temporary buried object; however, the method is not particularly limited.

Among the above-mentioned methods, a method of inserting a bag-shaped or tubular-shaped covering material into a temporary buried object so that the covering material can be worn from below, and mounting the temporary buried object in a sheet shape The method of wrapping with the formed coating material is more preferable because the workability of the coating operation is excellent. In addition, the method of fixing the covering material to the temporary buried object is not particularly limited. Further, as the fixing jig 11, specifically,
For example, a binder, a wire (number line), a string, a belt, a gum tape, and the like such as a cap formed by vertically dividing a tube such as a clothespin, a clip, a rubber hose, or a heat-insulating foam, but not particularly limited. Absent.

As described above, by covering the temporary buried object with the covering material, contact between the temporary buried object and the hydraulic composition can be suppressed, and both can be separated. The frictional resistance at the time of pulling out from the cured product of the hydraulic composition can be reduced. Therefore, the temporary buried object can be easily pulled out. The collected temporary buried objects can be reused as they are. The coating material is
Although the temporary buried object remains in the structure even after being pulled out, for example, when the covering material is fixed to the temporary buried object, it may be pulled out together with the temporary buried object.

In the above description, the covering material for covering the temporary buried material used for the structure composed of at least the temporary buried material and the cured product of the hydraulic composition has been described as an example. The covering material according to the present invention can be applied to temporary buried objects buried in soil. Thereby, the frictional resistance when the temporary buried object is pulled out from the soil can be reduced, and the temporary buried object can be easily pulled out.

Further, the coating material of the present invention may adopt a configuration in which the above resin layer is formed on the outer surface when the temporary burying object is covered. According to the above configuration, the work of pulling out the temporary buried object can be performed more easily, and the water-soluble resin dissolved in water does not adhere to the temporary buried object. Can be kept in a clean state and reused (recycle)
Becomes easier.

The coating material of the present invention may further employ a structure in which the above-mentioned bonding agent is a water-soluble resin. According to the above configuration, for example, in order to pull out the temporary embedded material from the cured product of the hydraulic composition, when the temporary embedded material is coated with a coating material, the water contained in the hydraulic composition is a water-soluble resin. Is dissolved, so that there is no possibility that the water-absorbing material impedes the volume expansion when the material absorbs water and swells. Therefore, the water absorbing material can sufficiently exhibit its water absorbing properties (performance). Thereby, the labor (tensile force) in the operation of pulling out the temporarily embedded object from the cured product of the hydraulic composition can be further reduced, and the workability of the operation can be improved.

The coating material of the present invention may further employ a structure in which the water absorbing material is a water-swellable resin. According to the above configuration, the swelled water-swellable resin exerts a lubricating effect, so that the temporary buried object becomes more slippery. Therefore, the workability of the work of pulling out the temporary buried object can be further improved.

The coating material of the present invention may further employ a structure in which the average particle diameter of the water-swellable resin is 2,000 μm or less. According to the above configuration, the mixing property of the bonding agent such as a water-soluble resin and the water-swellable resin becomes better, and the amount of the water-swellable resin adhered per unit area of the sheet-shaped substrate is reduced by the average particle size. The diameter can be increased as compared with the case where the diameter exceeds 2,000 μm, and the resin layer can be more easily formed. Therefore, the workability of pulling out the temporarily buried object and the work of pulling out the work can be further improved.

The covering material of the present invention may further adopt a structure in which the above-mentioned water-absorbing material is adhered to the outer surface in a state of covering the temporary buried object. According to the above configuration, the work of pulling out the temporary buried object can be performed more easily, and since the water absorbing material and the bonding agent do not adhere to the temporary buried object, the surface of the pulled out temporary buried object is cleaned. And it can be easily reused (recycled).

The coating material of the present invention may further employ a configuration in which the tensile strength of the sheet-like substrate is 1 kgf / 2.5 cm or more. According to the above configuration, it is possible to provide a covering material having a strength that does not break even when an external force such as an impact force or a tensile force generated when a temporary buried object is buried is applied.

The covering material of the present invention may further adopt a configuration formed in a bag shape or a tubular shape into which a temporary buried object can be inserted. According to the above configuration, the temporary buried object can be more easily and quickly covered.

[0084]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 A water-swellable resin was produced by crosslinking and copolymerizing sodium acrylate and acrylic acid under predetermined conditions. The average particle size of the water-swellable resin was 100 μm.

Then, the surface (one side) of a woven cloth (sheet-like substrate, polyester: cotton / 50: 50 (weight ratio), basis weight 200 g, thickness 0.5 mm) cut to the size of A4 plate
In addition, 1.25 g of starch paste (6% by weight)
Aqueous solution, water-soluble resin). 5.0 g of the water-swellable resin was evenly sprayed thereon, and 1.25 g of starch paste as a solid content was uniformly sprayed thereon. Next, the woven fabric to which the water-swellable resin was attached was dried at 120 ° C. for 15 minutes using a dryer. That is, a layer containing a water-swellable resin and starch was formed on one surface of the woven fabric. The woven fabric contains 40 starch.
g / m ² , and the water-swellable resin adhered at a rate of 80 g / m ² . The woven fabric has a tensile strength of 30 kgf / 2.
This was an extremely high value of 5 cm.

Next, the woven fabric on which a layer containing a water-swellable resin and starch was formed, that is, the coating material according to the present invention,
Sewn together so that the above layer is on the outside, width 80m
A bag of mx 140 mm in height was formed. An iron plate (manufactured by Nippon Test Panel Osaka) having a width of 70 mm, a height of 150 mm, and a thickness of 0.8 mm as a temporary buried object was inserted into the bag body.

On the other hand, soil cement milk (hydraulic composition) was prepared by mixing water, cement, clay and bentonite in a weight ratio of 25: 12: 16: 0.6. Then, the above bag was embedded in soil cement milk placed in a container. That is, after the iron plate covered with the covering material was driven into soil cement milk, the soil cement milk was cured.

Three days after the driving of the iron plate, the iron plate was pulled out of the cured product of the soil cement milk using a tensile tester. The pulling load required for the pulling operation was 0.9 kgf, and the iron plate could be pulled out very easily from the cured product of the soil cement milk.

Comparative Example 1 A coating material was prepared by performing the same operation as in Example 1. Next, this coating material was adhered to both sides of an iron plate having a width of 70 mm × a height of 150 mm × a thickness of 0.8 mm using an adhesive. That is, the coating material was directly fixed to both surfaces of the iron plate.

Next, the same operation as in Example 1 was performed to embed the iron plate in soil cement milk. That is, the iron plate for comparison to which the coating material was fixed was driven into the soil cement milk, and then the iron plate was pulled out from the cured product of the soil cement milk. The pulling load required for the drawing operation was 5.0 kgf, and the iron plate could not be easily pulled out from the cured product of the soil cement milk.

Example 2 Instead of a water-soluble resin, a synthetic rubber-based bonding agent (manufactured by Sumitomo 3M Limited; trade name "3")
The coating was produced using an M spray glue 99 "). The components of the bonding agent are 10% by weight of a synthetic rubber such as styrene-butadiene rubber, 40% by weight of an organic solvent such as n-pentane, acetone and toluene, and 50% by weight of a gas (for spraying) such as LPG and dimethyl ether.

First, a water-swellable resin was produced by crosslinking and copolymerizing sodium acrylate and acrylamide under predetermined conditions. The average particle diameter of the water-swellable resin was 200 μm.

Then, the amount of synthetic rubber (solid content) attached to the surface (one side) of the nonwoven fabric cut to the size of the A4 plate was 0.1%.
The bonding agent was uniformly spray-sprayed so as to be 5 g.
On top of that, 2.5 g of the water-swellable resin is evenly spread,
Further, the bonding agent was evenly spray-sprayed thereon such that the attached amount of the synthetic rubber became 1.5 g. Then, the same operation as described above was performed on the back surface of the nonwoven fabric so that the water-swellable resin was adhered with synthetic rubber. Next, the non-woven fabric to which the water-swellable resin has been adhered is dried at 100 ° C. using a dryer.
For 5 minutes. The non-woven fabric contains 64 g of synthetic rubber.
/ M ² , and the water-swellable resin adhered at a rate of 80 g / m ² .

Next, by performing the same operation as that of Example 1, the iron plate covered with the bag-like coating material was driven into soil cement milk, and then the iron plate was pulled out from the cured product of the soil cement milk. Was. The pulling load required for the drawing operation was 3.0 kgf, and the iron plate could be easily pulled out from the cured product of the soil cement milk.

[Comparative Example 2] The synthetic rubber-based bonding agent used in Example 2 was applied to a width of 70 mm x height of 150 mm x thickness of 0.8 m.
m was uniformly spray-sprayed on one side of an iron plate so that the amount of adhesion was 0.5 g. On top of that, 2.5 g of the water-swellable resin produced in Example 2 was evenly sprayed, and the bonding agent was further spray-sprayed thereon such that the attached amount of synthetic rubber became 1.5 g. . Then, the same operation as above was performed on the back surface of the iron plate so that the water-swellable resin was adhered with synthetic rubber. Next, the iron plate was dried at 100 ° C. for 5 minutes using a dryer. The synthetic rubber adhered to the iron plate at a rate of 64 g / m ² and the water-swellable resin adhered at a rate of 80 g / m ² .

Next, an iron plate not covered with the bag-shaped coating material according to the present invention was driven into soil cement milk by performing the same operation as in Example 1, and then the iron plate was washed with soil cement milk. From the cured product.
The pulling load required for the drawing operation was 7.0 kgf, and the drawing load was large as compared with the result of Example 2, and the iron plate could not be easily pulled out from the cured product of the soil cement milk.

Example 3 The surface (one side) of a woven cloth (sheet-like substrate, polyester: cotton / 65: 35 (weight ratio), basis weight 150 g, thickness 0.4 mm) cut to the size of A4 plate ), As a solid content, 1.25 g of 88% saponified polyvinyl alcohol (trade name Kuraray Poval PVA-21)
7, a water-soluble resin) was uniformly sprayed and sprayed with the aqueous solution of the polyvinyl alcohol.

Further, a water-swellable resin (average particle diameter: 100 μm) 5.0 produced by crosslinking and copolymerizing sodium acrylate and acrylic acid under predetermined conditions.
g as a solid content.
An aqueous solution of the polyvinyl alcohol was uniformly sprayed so that 25 g of 88% saponified polyvinyl alcohol adhered. Next, the woven fabric to which the water-swellable resin was attached was dried at 120 ° C. for 40 minutes using a dryer.
That is, a layer containing a water-swellable resin and polyvinyl alcohol was formed on one surface of the woven fabric. 88% saponified polyvinyl alcohol adhered to the woven fabric at a rate of 40 g / m ² , and a water-swellable resin adhered at a rate of 80 g / m ² . Further, the tensile strength of the woven fabric showed an extremely high value of 52 kgf / 2.5 cm.

Next, the woven fabric on which a layer containing a water-swellable resin and 88% saponified polyvinyl alcohol was formed, that is,
The covering material according to the present invention was sewn so that the above-mentioned layer was on the outside to form a bag body having a width of 80 mm and a height of 140 mm. In this bag, as a temporary buried object, width 70 mm
An iron plate (manufactured by Nippon Test Panel Osaka) having a height of 150 mm and a thickness of 0.8 mm was inserted.

Next, by performing the same operation as in Example 1, the iron plate covered with the bag-shaped coating material was driven into soil cement milk, and then the iron plate was pulled out from the cured product of the soil cement milk. Was. The pulling load required for the drawing operation was 0.7 kgf, and the iron plate could be easily pulled out from the cured product of the soil cement milk.

Example 4 A test was conducted on the polymer falling off the coating material according to the present invention, that is, on the polymer adhering to the woven fabric. First, based on the material of the covering material and the preparation method described in Example 3, the following three types of samples were prepared as samples for the dropout rate test. In addition, the polymer in this example indicates a combination of a water-soluble resin (a bonding agent) and a water-swellable resin (a water-absorbing material).

A. Example 3 except that the attached amount of 88% saponified polyvinyl alcohol was changed to 80 g / m ² (one side).
A sample was prepared by performing the same operation as described above.

A. Example 3 Example 3 was repeated except that completely saponified polyvinyl alcohol was used instead of the 88% saponified polyvinyl alcohol, and the amount of adhesion was 80 g / m ² (one side).
A sample was prepared by performing the same operation as described above.

C. Instead of 88% saponified polyvinyl alcohol, starch paste was used, and the adhesion amount was 80 g / m
^A sample was prepared by performing the same operation as in Example 3 except that ² (one side) was used.

Then, the ion-exchanged water was injected into the 100
The above three types of samples cut into a size of 5 cm × 5 cm were put in a ml container and immersed for 5 minutes. Then, these samples were pulled up from ion-exchanged water, excess water was removed and dried.

Next, from the weight change of the sample before and after immersion in ion exchange water (after drying), the amount of polymer dropped from the woven fabric was measured, and the amount (g) of the dropped polymer was measured. The drop-off rate (%) was calculated by dividing by the total polymer amount (g) adhering to the woven fabric before immersion in ion-exchanged water. That is, drop-off rate (%) = [(weight of sample before immersion (g) −weight of sample after immersion (g)) / (weight of sample before immersion)
(g) −weight of woven fabric (g)] × 100 A drop-off rate (%) was calculated.

As a result, the drop-out rates of the samples 1 and 2 were 28.5%, 11.6% and 70.9% in this order. Therefore, among the water-soluble resins (bonding agents), polyvinyl alcohol is more effective in preventing the water-swellable resin (water-absorbing material) from falling off from the woven fabric (sheet-like base material) before or during construction. It turned out to be even better.

[0109]

As described above, the coating material according to claim 1 of the present invention is a coating material for coating a temporary buried object in a non-adhered state, wherein the sheet-like base material contains a water-soluble resin. This is a configuration in which a layer is formed.

According to the above configuration, since the water-soluble resin dissolves, an easily peelable layer can be formed between the sheet-like base material and the cured product of the hydraulic composition. The labor (tensile force) in the work of pulling out from the cured product of the hydraulic composition can be reduced, and the workability of the work can be improved. Therefore, according to the above configuration, there is an effect that it is possible to provide a covering material that can improve the operation of pulling out the temporary buried object.

As described above, the coating material according to claim 2 of the present invention is a coating material for coating a temporary buried object in a non-adhered state, and comprises a sheet-like base material, a water absorbing material, and the water absorbing material. And a bonding agent to be attached to the sheet-like base material.

According to the above configuration, a layer of the swollen water-absorbing material can be formed between the temporarily embedded object and the cured product of the hydraulic composition, for example, so that the adhesion between the two can be further suppressed. Can be. Thus, when the temporary embedded object is pulled out from the cured product of the hydraulic composition, the swollen water-absorbing material exerts a lubricating effect, so that the temporary embedded object becomes slippery. Therefore, since the labor (tensile force) in the operation of pulling out the temporarily embedded object from the cured product of the hydraulic composition can be further reduced, it is possible to improve the workability of the operation. Further, by drying the water-absorbing material, a gap can be formed between the temporarily embedded object and the cured product of the hydraulic composition, so that the workability of the above operation can be further improved. Play together.

[0113] In the coating material according to the third aspect of the present invention, as described above, the water-soluble resin or the bonding agent is a water-soluble resin having a falling rate from the sheet-like substrate of 50% or less. It is.

According to the above configuration, the water-soluble resin (or bonding agent) can be further prevented from dropping off from the sheet-like base material before or during the construction, so that the sheet-like base material and the hydraulic A sufficient easy peeling layer can be formed between the composition and the cured product. Therefore, labor (tensile force) in the work of pulling out the temporary buried material from the cured product of the hydraulic composition
And the workability of the work can be improved.

As described above, the sheet-like flexible material according to the fourth aspect of the present invention comprises a sheet-like base material containing at least a water-soluble resin and a water-absorbing material. Is 50% or less.

According to the above configuration, for example, there is an effect that a sheet-like flexible material suitable for coating various articles can be provided.

[Brief description of the drawings]

FIGS. 1 (a) and 1 (b) are schematic perspective views showing a procedure for coating a temporary buried object using a coating material according to an embodiment of the present invention.

FIGS. 2A to 2D are schematic perspective views illustrating a procedure for coating a temporary buried object using a coating material according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coating material 2 Temporary buried thing 10 Coating material

Continuation of the front page (72) Inventor Hideyuki Tahara 992, Nishioki, Kohama-shi, Abashiri-ku, Himeji-shi BB00 DA01 DB05 EE03

Claims (4)

[Claims] 1. A coating material for covering a temporarily embedded object in a non-adhered state, wherein a resin layer containing a water-soluble resin is formed on a sheet-like base material. 2. A coating material for coating a temporarily embedded object in a non-adhered state, comprising a sheet-like base material, a water-absorbing material, and a bonding agent for attaching the water-absorbing material to the sheet-like base material. And the covering material. 3. The coating material according to claim 1, wherein the water-soluble resin or the bonding agent is a water-soluble resin having a falling rate from the sheet-like base material of 50% or less. 4. A sheet-like base material containing at least a water-soluble resin and a water-absorbing material, wherein the rate of falling off from the sheet-like base material is 50%.
A sheet-like flexible material comprising the following resin layer formed thereon.