JP3217734B2 - Concrete setting retarder and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete setting retarder, and more particularly to a tape-like or sheet-like concrete setting retarder used for attaching a tile to a precast concrete board (PC board). is there.

[0002]

2. Description of the Related Art As a conventional concrete setting retarder which is the background of the present invention, for example, JP-A-48-2982 is known.
No. 1 discloses a sheet coated with an adhesive compounded with a cement setting retarder. This sheet is
When the tiles are attached to the C-plate, it is for delaying the setting of excess concrete oozing out from between the tiles and making it easy to remove. In this case, as the adhesive applied to the back surface of the sheet, a mixture of an adhesive component composed of an acrylate resin and a starch paste and a lignin sulfonate as a cement setting retarder is used.
On the adhesive surface of the concrete setting retarder, the tiles are temporarily attached in a state of being arranged in advance. Then, the concrete setting retarding material to which the tile is attached is laid in a formwork, and concrete is driven from above. When the concrete sets, the tiles are integrally fixed to the surface. Thereafter, the sheet is removed. At this time, part of the concrete oozes from the joints between the tiles to the tile surface on the adhesive side, but is in an unset state due to the action of the cement setting retarder, so that it can be easily removed by washing. it can.

[0003]

However, in the conventional concrete setting retarder, the dispersibility of the retarder in an adhesive such as an adhesive or a pressure-sensitive adhesive has not been considered so much. If the dispersibility of the retarder in the patch is poor, the retarder does not disperse uniformly in the patch, resulting in unevenness due to unevenness, and the effect of delaying the setting of concrete is uniformly obtained on the surface of the patch layer. May not be possible. In particular, when a delaying agent such as sucrose having a property of being hardly dissolved in an organic solvent is used in combination with an organic solvent-based patch, the dispersibility of the retarding agent with respect to the patch is poor. Inconvenience is likely to occur. In order to prevent this, kneading for a long time is required, or processing such as reducing the particle size of the retarder is required to facilitate mixing, and in this case, an increase in manufacturing cost is inevitable . In addition, in order to mix easily with the adhesive, the retarder may be processed into a paste with a plasticizer or the like before use. However, also in this case, the processing cost is increased, and as a result of the plasticizer remaining in the adhesive layer, there is a disadvantage that the adhesiveness or adhesive property of the adhesive to the substrate is significantly reduced. Further, as another problem, when the base material is formed of paper, various inconveniences may occur because the base material is weak to moisture and has low physical strength.
In order to solve this, a substrate made of a film-like or sheet-like synthetic resin having a high tear strength has been conventionally used, but in this case, cutting was difficult without using scissors or a cutter.

[0004] Therefore, a main object of the present invention is to provide a concrete setting retarder in which a retarder is uniformly dispersed in an adhesive layer, has excellent retardation effect, tackiness and curing property, and has a so-called hand-cutting property. It is to provide.

[0005]

A concrete setting retarder according to the present invention is formed on at least one principal surface of a tape-like or sheet-like base fabric whose tear strength is weakened in at least one direction and a base fabric. Concrete comprising a base material comprising an overcoat layer, and an adhesive layer formed on the overcoat layer, which serves to delay the setting of the concrete and temporarily adheres an adherend such as a tile. A setting retarder, the adhesive layer is applied on the overcoat layer of the base material, the adhesive is uniformly mixed with an aqueous solution containing alcohol as a retarder for retarding the setting of the concrete, and then dried. Is a concrete setting retarder formed by removing water and an organic solvent. Applying the retarder in advance as an aqueous solution containing alcohol, uniformly mixing with the adhesive and applying it to the substrate, and then removing the water and organic solvent, compared to kneading in a solid state Uniform dispersion in the patch with a very small particle size can be easily and at low cost. Therefore, the concrete setting retarder according to the present invention can uniformly delay the setting of concrete over the entire surface of the adhesive layer. In addition, the concrete setting retarder according to the present invention can be cut relatively easily by a worker tearing by hand, since most of the base material is formed of a base cloth having a reduced tear strength in at least one direction. . This is referred to in this specification as having good hand-cutting properties. Therefore, it is easy to cut into desired dimensions at the time of construction without using tools such as scissors and cutters. Moreover, the concrete setting retarder according to the present invention can reduce the amount of the organic solvent used and the amount of waste, can reduce the production cost, and is suitable for mass production. Furthermore, since the overcoat layer is formed on the main surface of the base fabric, the unevenness of the base fabric surface becomes smooth, and the impregnation of the solution can be prevented.
It is possible to save the use amount of the patch containing the retarder. In addition, the strength of the base material is improved, and the influence of moisture can be minimized. The overcoat layer is preferably formed in a thin layer mainly composed of a synthetic resin that does not impair hand-cutting properties. In this case, for example, it is preferable that a polyethylene cloth is used for the base cloth, polyethylene is laminated on one or both sides thereof, and a corona discharge treatment is performed on one or both sides to form an overcoat layer.

Further, in the concrete setting retarder according to the present invention, the adhesive layer comprises an aqueous solution containing alcohol of sucrose as a retarder for delaying the setting of concrete and a solvent-type acrylic pressure-sensitive adhesive. A concrete setting retarder formed by applying a uniformly mixed material onto the overcoat layer of the base material and then drying to remove moisture and an organic solvent, and an aqueous solution containing alcohol of sucrose is Contains 25% by weight or less of water relative to the solvent content of the solvent-type acrylic pressure-sensitive adhesive, and the alcohol content is adjusted to 5 to 60 parts by weight with respect to 100 parts by weight of water. Sucrose is 5 to 60 solids per 100 parts by weight of solids
It is preferred to be blended in parts by weight. Moreover, it is preferable to adjust sucrose so that the solid content concentration is 55 to 65%. Sucrose can be easily and inexpensively obtained as a white sugar or the like, and has a desired retardation effect. However, in a solid state, dispersibility in an adhesive is poor, and conventionally, it is generally applied alone. It could not be blended in the agent layer and was made into a paste with a plasticizer. However, according to the present invention, sucrose as a retarder can be uniformly dispersed in a patch layer without using a plasticizer or the like that deteriorates the properties of the patch. In this case, if the components are blended in the above-mentioned mixing ratio, a favorable delay effect and adhesive properties can be simultaneously obtained.

Further, the method for producing a concrete setting retarder according to the present invention includes the steps of uniformly mixing an aqueous solution containing a retarder alcohol with an adhesive on at least one principal surface of a substrate, A method of uniformly mixing an aqueous solution containing a retarder alcohol with an adhesive, and drying and removing water and an organic solvent, to remove concrete setting retarder. Since the aqueous solution containing the alcohol of the retarder is easily dispersed uniformly in the patch, if the water and the organic solvent are subsequently removed, a patch layer in which the retarder is uniformly dispersed can be easily obtained. . In addition, in this case, the fine particle retarder can be more uniformly dispersed in the patch than by kneading in a solid state. Therefore, according to the present invention, a concrete setting retarder in which a retarder is uniformly dispersed in an adhesive layer can be easily obtained.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention with reference to the accompanying drawings.

[0009]

FIG. 1 is a schematic sectional view showing an example of a concrete setting retarder according to the present invention. The concrete setting retarder 10 is in the form of a tape or a sheet.
It is used for the same purpose as that disclosed in Japanese Patent Application Laid-Open Publication No. H11-32139, that is, for pasting a tile on a PC board in advance. However, it goes without saying that it may be used simply to delay the setting of the concrete surface.

The concrete setting retarder 10 includes a tape-shaped or sheet-shaped base material 12. The base material 12 is required to have a physical strength capable of withstanding the weight of the tiles to be stuck and a moisture resistance capable of withstanding the moisture at the time of applying the adhesive described later and the moisture of the concrete before setting.
Further, from the viewpoint of workability, it is preferable to use a so-called hand-cutting material which can be easily cut in a certain direction without using a tool.
Therefore, in the concrete setting retarder 10, the base fabric 1 having a reduced tear strength in at least one direction is used.
The overcoat layer 16 formed on one or both surfaces of the substrate 4 is used as the substrate 12. As the base fabric 14, for example, a woven fabric or a nonwoven fabric formed using polyethylene flat yarn is used. in this case,
The base fabric 14 is formed so as to have a lower tear strength in the weft direction than in the warp direction, and is formed so as to be easily cut in the weft direction by hand without using tools such as scissors and a cutter. On the other hand, the overcoat layer 16 formed on the base cloth 14 is formed by laminating a synthetic resin such as polyethylene, for example, on one or both sides of the base cloth 14 so as not to impair the hand-cutting property, and forms corona discharge on one or both sides. It is formed by processing. Overcoat layer 16
Improves the mechanical strength and moisture resistance of the base cloth 14, smoothes the irregularities on the surface of the base cloth 14, prevents the impregnation of the base cloth 14 with a liquid, and allows the adhesive containing a retarder to be described later. It works to reduce the amount of used. The substrate 12 is not limited to the above-described one, and may be, for example, a stretched film as long as it is formed to be easily torn in at least one direction by hand.

Further, the concrete setting retarder 1
0 overcoat layer 16 on one or both sides of substrate 12
The adhesive layer 18 is formed by applying a mixture obtained by uniformly mixing an aqueous solution containing the alcohol of the retarder and the adhesive to a predetermined thickness, and then drying and removing the water and the organic solvent. Is done. The adhesive layer 18 is for temporarily attaching the base material 12 to the surface of an object to be attached such as tile or concrete, and for delaying the setting of the surface of the attached concrete for a predetermined time.

The adhesive is for temporarily bonding or adhering the base material 12 to an adherend, and in this specification, is used to include both an adhesive and a pressure-sensitive adhesive. As the adhesive, for example, a solution-type acrylic adhesive in which a solid content is dissolved in an organic solvent is used. As a cross-linking agent for cross-linking the solvent-type acrylic pressure-sensitive adhesive, for example, an epoxy-based, metal chelate-based, amine-based cross-linking agent, or the like is used alone or in combination.
The crosslinking agent is blended in an amount of 0.01 to 5.0 parts by weight based on 100 parts by weight of the solid content of the acrylic pressure-sensitive adhesive. It is to be noted that an isocyanate-based cross-linking agent is not preferable because it particularly dislikes the presence of water. However, it can be used as a primer for the substrate 12.

[0013] On the other hand, the retarder is for delaying the setting of the contacted concrete surface for a predetermined time. As the retarder for the concrete setting retarder 10, sucrose, particularly, white sucrose is used. Since white sugar is water-soluble, it is suitable for use in the composition of the present invention, is easily and inexpensively available, is easy to handle,
The effect of delaying concrete setting is sufficiently obtained. The solid content of white sucrose as a retarder is 5 to 60 parts by weight per 100 parts by weight of the solid content of the solvent-type acrylic pressure-sensitive adhesive.
It is preferred to be blended in a ratio by weight. If the amount is less than 5 parts by weight, the delay effect cannot be sufficiently obtained, and if the amount is more than 60 parts by weight, the delay effect becomes too large and the tile is delayed to the joint portion. However, if the amount is more than 30 parts by weight, the adhesiveness of the adhesive to the substrate may be reduced. In this case, adhesion can be improved by applying a primer for urethane-based polyethylene or the like as a primer on the coated surface of the adhesive on the base material in advance. Further, the aqueous solution containing the alcohol of white sucrose as a retarder is prepared such that the amount of water is 30% or less, preferably 25% or less by weight based on the organic solvent component of the solvent-type acrylic pressure-sensitive adhesive. You. This is because when the weight ratio of water to the organic solvent is 25% or more, the pressure-sensitive adhesive and water are apt to undergo phase separation, and the drying property during production is deteriorated, which further lowers the tackiness. This is because such inconvenience is likely to occur. Further, the concentration of the aqueous solution containing the alcohol of upper sucrose as a retarder is from 55%
% Is preferable. If the concentration is lower than this, the drying property and the like deteriorate, and if the concentration is higher than this, the solubility deteriorates.
In order to minimize the amount of water, a lower alcohol such as isopropyl alcohol, which is compatible with both the organic solvent and water, is added at the same time. Drying during production can also be improved by the addition of alcohol. The alcohol is preferably added in the range of, for example, 5 to 60% based on water. If the amount is less than 5%, the effect of adding alcohol cannot be obtained, and if the amount is more than 60%, the solubility of the retarder deteriorates. In addition, you may use another saccharides, such as glucose and mannose, as a retarder. Also, substances conventionally known as retarders,
For example, oxycarboxylic acids such as sodium gluconate and citric acid, ketocarboxylic acids, sorbitol and other substances can be selected.

[0014]

EXAMPLE A tape-like single-sided corona-treated polyethylene cloth having a thickness of 0.100 mm, a width of 310 mm and a length of 50 m having a polyethylene laminated layer formed on both sides was prepared as the above-mentioned base material. The polyethylene cloth tape as the base material is torn by hand,
It is formed so that it can be cut straight in the width direction. In this embodiment, a product name: P manufactured by Hagiwara Kogyo Co., Ltd.
E Lamic cloth (one-sided corona treated product) was used. Further, based on 100 parts by weight of a solvent-type acrylic pressure-sensitive adhesive (manufactured by Soken Chemical Co., Ltd., trade name: SK Dyne 1633H), 5 to 60 parts of white sugar as a retarder (solid content of 55 A 65% aqueous solution) and an epoxy-based cross-linking agent (trade name: E-5C, manufactured by Soken Chemical Co., Ltd.) in an amount of 0.1 to 1.0 part by weight were prepared. The solvent-based acrylic pressure-sensitive adhesive used in this example was completed as a pressure-sensitive adhesive by removing the organic solvent and crosslinking with a crosslinking agent. In addition, in order to improve the adhesion between the substrate and the adhesive, a primer process was performed on the adhesive-coated surface (corona-treated surface) of the substrate. Then, the mixed solution is applied to one side (primer-coated side) of the base material by a coater on a base material, and then dried at 85 ° C. for 2 minutes or more to obtain a thickness of 0.1 μm.
A patch layer of 07 mm was formed. Then, at room temperature (23 ° C
-30 ° C) for 7 days to obtain a concrete setting retarder.

Next, the relationship between the compounding amount of white sugar as a retarder of the concrete setting retarder and the retarding effect, adhesive strength and curing property was examined. Here, the delay effect means that the concrete can be easily washed and removed three days after the concrete setting retarder is attached to the concrete surface before setting. Here, 4 kg of instant Sunday cement manufactured by the household chemical industry,
0 cc was used for testing. The adhesive strength was determined according to a test method specified in JIS Z0237. Furthermore, the curing property is that the tile is stuck on the surface of the adhesive layer, left in a thermo-hygrostat at 65 ± 5 ° C. and 80 ± 5% relative humidity for 48 hours, and then the tile is peeled off and stuck on the tile surface. The degree of residual adhesive was visually examined. Here, as a tile, a so-called rough stone tile was used. Table 1 shows the results.

[0016]

[Table 1]

As apparent from Table 1, in this test, the best balance was obtained when the mixing ratio of the solid content of white sugar as a retarder was 30 to 40 parts by weight with respect to 100 parts by weight of the solid content of the adhesive. It has been found that it exhibits excellent performance. When the compounding ratio of the retarder is 5 to 20 parts by weight, the retarding effect is slightly weak, and the compounding ratio of the retarder is 50 to 50 parts by weight.
In the case of 60 parts by weight, the delay effect is too large.
However, even in these cases, it can be considered that they can be used according to the actual use situation.

[0018]

According to the present invention, a concrete setting retarder in which a retarder is uniformly dispersed in an adhesive layer can be obtained. In this concrete setting retarder, since the retarder is uniformly dispersed in the adhesive layer, the effect of delaying concrete setting on the surface of the adhesive layer can be obtained uniformly. Therefore, if this concrete setting retarder is used, excess concrete at the time of curing the tile or concrete can be easily and effectively removed. In addition, since the concrete setting retarder according to the present invention can be easily cut by tearing by a worker, the workability during construction is improved. Moreover, the concrete setting retarder according to the present invention can reduce the amount of the organic solvent used and the amount of waste, can reduce the production cost, and is suitable for mass production.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one example of a concrete setting retarder according to the present invention;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Concrete setting delay material 12 Base material 14 Base cloth 16 Overcoat layer 18 Adhesive layer

Claims (3)

(57) [Claims] 1. A base material comprising a tape-like or sheet-like base fabric having a weakened tear strength in at least one direction and an overcoat layer formed on at least one principal surface of the base fabric, and on the overcoat layer A concrete setting delay material which has a function of delaying the setting of concrete and has an adhesive layer for temporarily adhering an adherend such as a tile; and The layer is provided with a patch uniformly mixed with an aqueous solution containing an alcohol as a retarder for retarding the setting of concrete, on the overcoat layer of the base material, and then dried to remove moisture and organic solvents. A concrete setting delay material formed by: 2. The adhesive layer is prepared by uniformly mixing an aqueous solution containing sucrose alcohol as a retarder for retarding the setting of concrete and a solvent-type acrylic pressure-sensitive adhesive. Applied on the overcoat layer,
A concrete setting retarder formed by removing water and an organic solvent by drying thereafter, wherein an aqueous solution containing an alcohol of the sucrose is in a weight ratio to a solvent content of the solvent-based acrylic pressure-sensitive adhesive. And the alcohol content is adjusted so as to be 5 to 60 parts by weight with respect to 100 parts by weight of water, and based on 100 parts by weight of the solid content of the solvent-based acrylic pressure-sensitive adhesive, The concrete setting retarder according to claim 1, wherein sucrose is blended in a ratio of 5 to 60 parts by weight in solid content. 3. A step of uniformly applying an aqueous solution containing the alcohol of the retarder to the patch to at least one principal surface of the base material, and uniformly applying the aqueous solution containing the alcohol of the retarder to the patch. A method for producing a concrete setting retarder, comprising a step of drying and removing water and an organic solvent from a mixture obtained by mixing the above.