JP2019172536A - Self-levelling material and concrete floor structure - Google Patents

Abstract

To provide a self-levelling material having quick hardening and quick drying property, and further hardly reducing adhesiveness to an underlayer concrete even when used at inside and outside locations which are easily affected by environment such as water immersion or temperature change, and excellent in weather resistance.SOLUTION: A water hard component contains Portland cement of 15 to 45 mass%, alumina cement of 35 to 65 mass% and gypsum of 20 to 40 mass%. Content of a re-emulsified resin powder is 1 to 15 pts.mass based on 100 pts.mass of the water hard component. Content of a blast furnace slag fine powder is 40 to 120 pts.mass based on 100 pts.mass of the water hard component. Content of a fine aggregate is 80 to 200 pts.mass based on 100 pts.mass of the water hard component. A hardening accelerator contains a lithium salt. Content of the lithium salt is 0.01 to 2.0 pts.mass based on 100 pts.mass of the water hard component. Content of an aliphatic acid metal salt is 0.1 to 2 pts.mass based on 100 pts.mass of the water hard component.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a self-leveling material and a concrete floor structure that are used as a floor base material or a floor finishing material for construction of a floor surface of a structure.

  The self-leveling material is mainly used as a floor base material, and has excellent fluidity and moderate strength, and is required to be fast-curing and quick-drying. Therefore, a material containing alumina cement is known. . In addition, in order to improve the surface properties of the hardened body of the self-leveling material and the adhesion to the ground concrete, some contain a polymer resin, and it can also be used as a floor for a factory floor or a parking lot, or as a floor finish. May be used. In particular, even when used outdoors or indoors, such as around external corridors and entrances, food factories, underground, etc., where moisture intrusion or temperature changes are large and are susceptible to environmental influences, even better durability is achieved. It is considered necessary.

  Patent Document 1 discloses a hydraulic composition containing a re-emulsifying resin powder mainly composed of an acrylic copolymer in a hydraulic component made of alumina cement, Portland cement, and gypsum.

  Patent Document 2 includes a hydraulic component made of alumina cement, Portland cement, gypsum, fine powder of blast furnace slag, fine aggregate, re-emulsifying resin powder mainly composed of vinyl acetate / acrylic copolymer, fluidizing agent, A floor finish self-leveling material containing a thickener, a curing accelerator and a set retarder is shown.

JP 2008-273811 A JP 2017-226575 A

  However, the self-leveling material described in Patent Documents 1 and 2 contains re-emulsified resin powder when trying to be applied outdoors or indoors where moisture intrusion or temperature change is large and easily affected by the environment. Even so, the adhesive strength between the cured body of the self-leveling material and the ground concrete due to repeated heating and cooling occurs, so that the adhesion stability between the cured body of the self-leveling material and the ground concrete is improved. Improvement was needed.

  Therefore, the present invention can obtain a self-leveling mortar excellent in fluidity and smoothness, has a fast curing and quick drying property, and has a large moisture ingress or temperature change outdoors or indoors. The main object is to provide a self-leveling material excellent in weather resistance, in which the adhesion to the underlying concrete is unlikely to deteriorate even when used in a location that is susceptible to the influence of the above.

  As a result of diligent studies to achieve the above object, the present inventors have found that the hydraulic component, blast furnace slag fine powder, fine aggregate, re-emulsified resin powder, water reducing agent, thickening agent comprising alumina cement, Portland cement and gypsum. Self-leveling material containing an agent, curing accelerator, setting retarder, and fatty acid metal salt has excellent fluidity, smoothness, and rapid hardening, and is a base concrete for cured bodies even in environments where it is subjected to repeated heating and cooling. As a result, it was found that the adhesiveness to the resin was hardly lowered, and the present invention was completed.

  The self-leveling material according to the present invention contains a hydraulic component, blast furnace slag fine powder, fine aggregate, re-emulsified resin powder, water reducing agent, thickener, curing accelerator, setting retarder, and fatty acid metal salt. The hydraulic component includes 15% to 45% by weight of Portland cement, 35% to 65% by weight of alumina cement, and 20% to 40% by weight of gypsum. Content of re-emulsification resin powder is 1-15 mass parts with respect to 100 mass parts of hydraulic components. Content of blast furnace slag fine powder is 40 mass parts-120 mass parts with respect to 100 mass parts of hydraulic components. The content of the fine aggregate is 80 parts by mass to 200 parts by mass with respect to 100 parts by mass of the hydraulic component. The curing accelerator includes a lithium salt. Content of lithium salt is 0.01 mass part-2.0 mass parts with respect to 100 mass parts of hydraulic components. Content of fatty-acid metal salt is 0.1 mass part-2 mass parts with respect to 100 mass parts of hydraulic components.

  According to the present invention, it is possible to obtain a self-leveling mortar excellent in fluidity and smoothness, has a fast curing and quick drying property, and has a large moisture ingress or temperature change outdoors or indoors. It is possible to provide a self-leveling material excellent in weather resistance, in which the adhesiveness of the cured body to the base concrete is not lowered even when used in a location that is susceptible to the influence of the above.

  In the self-leveling material according to the present invention, the fatty acid metal salt is preferably an aliphatic aluminum, calcium or zinc salt having 18 or more carbon atoms. In this case, the durability and weather resistance of the cured body of the self-leveling material can be further improved. In addition, even after repeated heating and cooling, the adhesiveness of the cured body to the underlying concrete is less likely to decrease.

  In the self-leveling material according to the present invention, the main component of the re-emulsifying resin powder is preferably a vinyl acetate / acrylic copolymer. In this case, the durability and weather resistance of the cured body of the self-leveling material can be further improved. In addition, even after repeated heating and cooling, the adhesiveness of the cured body to the underlying concrete is less likely to decrease.

  In the self-leveling material according to the present invention, the coarse aggregate ratio of the fine aggregate is 0.60 to 1.40, the water absorption is 3.0% or less, and the sieve opening of the fine aggregate is only 0.3 mm. The mass fraction is preferably 5.0% to 50%.

  A concrete floor structure according to the present invention includes a primer layer mainly composed of an acrylic resin provided on a concrete floor layer, and a self-leveling material according to the present invention provided on the primer layer. A cured body layer.

  According to the present invention, it is possible to obtain a self-leveling mortar excellent in fluidity and smoothness, has a fast hardening and quick drying property, and further has a large water penetration or temperature change even outdoors or indoors. A self-leveling material excellent in weather resistance can be provided in which the adhesiveness of the cured body to the ground concrete is not lowered even when used in a place that is susceptible to environmental influences.

It is a schematic diagram which shows a concrete floor structure. It is a schematic diagram which shows SL measuring device. It is a schematic diagram which shows the measuring method of SL value.

  Embodiments of the present invention will be described with reference to the drawings. However, the following embodiments are exemplifications for explaining the present invention and are not intended to limit the present invention to the following contents. In the description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

<Self-leveling material>
The self-leveling material of this embodiment contains a hydraulic component, blast furnace slag fine powder, fine aggregate, re-emulsified resin powder, water reducing agent, thickener, curing accelerator, setting retarder, and fatty acid metal salt.

  In the self-leveling material of this embodiment, the hydraulic component includes 15% by mass to 45% by mass of Portland cement, 35% by mass to 65% by mass of alumina cement, and 20% by mass to 40% by mass of gypsum. For this reason, the self-leveling material of the present embodiment has excellent fluidity and quick hardening / fast drying. Moreover, the self-leveling material of this embodiment has little volume change during hardening.

  From the viewpoint of realizing better fluidity, quick curing and quick drying, a lower volume change rate during curing, and a lower material cost, the blending ratio of the hydraulic component is preferably 18% by mass to 43% by mass of Portland cement, Alumina cement 35 mass% to 60 mass% and gypsum 20 mass% to 38 mass%, more preferably Portland cement 20 mass% to 40 mass%, alumina cement 35 mass% to 55 mass%, and gypsum 21 mass% to 35 mass%. More preferably, Portland cement is 23% by mass to 38% by mass, Alumina cement is 37% by mass to 53% by mass, and Gypsum is 23% by mass to 33% by mass, and particularly preferably Portland cement is 25% by mass to 35% by mass. %, Alumina cement 40 mass% to 50 mass% and gypsum 24 mass% to 30 mass%.

  As the Portland cement, for example, normal Portland cement, early-strength Portland cement, ultra-early strong Portland cement, moderately hot Portland cement, low heat Portland cement, sulfate-resistant Portland cement and the like can be used. Moreover, mixed cements such as blast furnace cement, fly ash cement, silica cement and the like can be used as an alternative. From the viewpoint of quick setting, it is preferable to use ordinary Portland cement, early-strength Portland cement, or ultra-early-strength Portland cement.

Blaine specific surface area of the Portland cement is preferably 3000cm ² / g~6000cm ² / g, more preferably from 4000cm ² / g~5000cm ² / g, further preferably 4200cm ² / g~4800cm ² / g is there. The Blaine specific surface area of Portland cement is calculated | required according to JISR5201. By setting the Blaine specific surface area of Portland cement within the above preferred range, it is possible to achieve an excellent balance of strength development and setting time when the hydraulic component is three components of Portland cement, alumina cement and gypsum.

Several types of alumina cement having different mineral compositions are known and commercially available, but their main component is monocalcium aluminate (CA), and commercially available products can be used regardless of the type. ^It is preferable to use the alumina cement having a Blaine specific surface area of 2000cm ² / g~6000cm 2 / g. The brain specific surface area of the alumina cement is determined according to JIS R 5201.

  Examples of gypsum include dihydrate gypsum, hemihydrate gypsum, and anhydrous gypsum. Use gypsum by-produced in flue gas desulfurization and hydrofluoric acid production processes, or gypsum produced in nature. Can do. From the viewpoint of fluidity and strength development, anhydrous gypsum is preferably used.

Blaine specific surface area of the gypsum ^is preferably 2000cm ² / g~7000cm 2 / g. When the brane specific surface area of gypsum is in the above range, it is easy to handle gypsum. Moreover, since the gypsum having the above-mentioned Blaine specific surface area is highly versatile, it can be obtained at a low cost. The brane specific surface area of gypsum is determined according to JIS R 5201.

Blaine specific surface area of the gypsum, and more preferably from 2500cm ² / g~6000cm ² / g, more preferably from 2750cm ² / g~5500cm ² / g, particularly preferably 3000cm ² / g~5000cm ² / g is there. When the specific surface area of the gypsum is within the above-described preferable range, the handling of the gypsum becomes easier. Moreover, since the gypsum having the above-mentioned Blaine specific surface area is more versatile, it can be obtained at a lower cost.

  It is preferable that the self-leveling material of this embodiment contains blast furnace slag fine powder. By containing blast furnace slag, fluidity can be further improved, volume change during curing can be reduced, and durability of the cured product can be further improved. Blast furnace slag fine powder preferably used includes blast furnace slag fine powder defined in JIS A 6206 “Blast furnace slag fine powder for concrete”.

Blaine specific surface area of the ground granulated blast furnace slag is preferably 3000 cm ² / g or more, more preferably from 3000cm ² / g~8000cm ² / g, more preferably from 3500cm ² / g~6000cm ² / g, Most preferably, it is 4000 cm < ² > / g-5000 cm < ² > / g. The Blaine specific surface area of blast furnace slag fine powder is calculated | required according to JISR5201.

  When the Blaine specific surface area of the blast furnace slag fine powder is within the above preferred range, excellent fluidity, dimensional stability and strength development can be obtained.

  The content of the blast furnace slag fine powder is 40 to 120 parts by mass, preferably 45 to 100 parts by mass, more preferably 50 to 90 parts by mass with respect to 100 parts by mass of the hydraulic component. And particularly preferably 55 to 80 parts by mass, and most preferably 55 to 70 parts by mass. When the content of the blast furnace slag fine powder is in the above range, excellent fluidity, dimensional stability and strength development can be obtained.

  The fine aggregate used for the self-leveling material of the present embodiment has a maximum particle diameter of 0.85 mm or less, and 5 mass% of coarse particles having a particle diameter of more than 0.6 mm in 100 mass% of fine aggregate. It is preferable to contain less than. As such fine aggregate, for example, sand such as quartz sand, river sand, land sand, sea sand, crushed sand, slag fine aggregate, regenerated fine aggregate, alumina cement clinker and the like can be appropriately selected and used. In particular, as the fine aggregate, those selected from sands such as quartz sand, river sand, land sand, sea sand and crushed sand and alumina cement clinker can be suitably used.

  The particle diameter of the fine aggregate can be determined according to the aggregate screening test method defined in JIS A1102. Further, in this specification, “coarse fraction having a particle diameter of greater than 0.6 mm” means a mass fraction of fine aggregates that remain on the sieve when a sieve having a sieve mesh of 0.6 mm is used ( %).

  When the fine aggregate contains 5% or more of coarse particles having a particle diameter of more than 0.6 mm, the fluidity of the self-leveling material tends to decrease. The lower limit of the coarse particles is not particularly limited and may be 0%. In order to obtain excellent fluidity, the coarse particle content in the fine aggregate is more preferably 0% to 3%, further preferably 0% to 0.5%, and particularly preferably 0.01% to 0.2%.

  The mass fraction remaining in each sieve of the fine aggregate is preferably 0.1% to 5.0% with a sieve opening of 0.425 mm, and 5.0% to 50.0 with a sieve opening of 0.3 mm. %, 30.0% to 90.0% when the sieve opening is 0.212 mm, 60.0% to 99.0% when the sieve opening is 0.15 mm, and more preferably 0 when the sieve opening is 0.425 mm. 0.1% to 4.0%, sieve opening 0.3% to 10.0% to 40.0%, sieve opening 0.212mm to 35.0% to 89.0%, sieve opening 0.15mm 65.0% to 98.0%, more preferably 0.1% to 3.0% with a sieve opening of 0.425 mm, 15.0% to 35.0% with a sieve opening of 0.3 mm, 35.0% to 87.5% at 0.212 mm sieve opening, 0.15 mm sieve opening 65.0% to 97.0%, particularly preferably 0.1% to 1.5% with a sieve opening of 0.425 mm, 17.0% to 30.0% with a sieve opening of 0.3 mm, It is 40.0% to 85.0% when the sieve opening is 0.212 mm, and 70.0% to 95.0% when the sieve opening is 0.15 mm.

  When the mass fraction remaining on each sieve of the fine aggregate is within the above range, it is possible to obtain more excellent fluidity and better quick hardening and quick drying.

  The coarse particle ratio of the fine aggregate is preferably 0.60 to 1.40, more preferably 0.68 to 1.35, still more preferably 0.72 to 1.28, and particularly preferably. 0.74 to 1.25. The water absorption rate of the fine bone agent is preferably 3.00% or less, more preferably 2.95% or less, still more preferably 2.90% or less, and particularly preferably 2.80% or less. . Thereby, more excellent fluidity can be obtained.

  In the present specification, the “coarse grain ratio” refers to the coarse grain ratio of the aggregate as defined in JIS A 1102. Further, the “water absorption rate” refers to a value measured according to the method for measuring the water absorption rate (unit:%) of an aggregate defined in JIS A 1109.

  The content of the fine aggregate is 80 parts by mass to 200 parts by mass with respect to 100 parts by mass of the hydraulic component, preferably 85 parts by mass to 180 parts by mass, and more preferably 90 parts by mass to 160 parts by mass. Yes, particularly preferably 95 parts by mass to 140 parts by mass, and most preferably 100 parts by mass to 120 parts by mass. When the content of the fine aggregate is within the above range, excellent fluidity and excellent quick hardening and quick drying can be obtained.

  The self-leveling material of this embodiment contains re-emulsifying resin powder. For this reason, the hardened | cured mortar body and floor structure which have the outstanding surface strength, abrasion resistance, adhesiveness with foundation concrete, durability, and a weather resistance are implement | achieved.

  The composition of the main component of the re-emulsifying resin powder is not particularly limited. From the standpoint of further improving weather resistance such as resistance to ultraviolet rays, the main component of the re-emulsified resin powder is preferably an acrylic copolymer, and particularly preferably a vinyl acetate / acrylic copolymer. preferable.

  The glass transition temperature (Tg) of the re-emulsified resin powder is preferably 0 ° C to 20 ° C, more preferably 5 ° C to 15 ° C, and particularly preferably 8 ° C to 12 ° C. By setting the glass transition temperature (Tg) of the re-emulsified resin powder within the above preferred range, a cured product having high bending strength at room temperature can be obtained.

  The minimum film-forming temperature (MFT) of the re-emulsified resin powder is preferably -5 ° C to 5 ° C, more preferably -2 ° C to 4 ° C, and particularly preferably -1 ° C to 3 ° C. By setting the minimum film-forming temperature (MFT) of the re-emulsified resin powder within the above preferred range, a cured product having high bending strength at normal temperature can be obtained.

  The content of the re-emulsified resin powder is preferably 1 part by mass to 15 parts by mass, more preferably 2 parts by mass to 12 parts by mass, and further preferably 3 parts by mass with respect to 100 parts by mass of the hydraulic component. 10 parts by mass, and particularly preferably 4 parts by mass to 8 parts by mass. If the content of the re-emulsified resin powder is too small, the surface strength of the cured body may be too low, or the adhesion and adhesion stability between the cured body and the ground concrete may be too low. When the content of the re-emulsified resin powder is too large, not only the cost of the self-leveling material increases, but also the viscosity increases and the amount of kneading water for obtaining desired fluidity may increase.

  The self-leveling material of the present embodiment is preferably used with a small amount of kneading water in order to suppress separation of the material and obtain a high-strength cured body. Therefore, the self-leveling material of this embodiment preferably contains a water reducing agent having a water reducing effect.

  As the water reducing agent, for example, commercially available water reducing agents such as formaldehyde condensate of melamine sulfonic acid, casein, calcium caseinate, polycarboxylic acid type, polyether type and polyether polycarboxylic acid type, which have a water reducing effect, Can be used regardless of type.

  The content of the water reducing agent can be appropriately contained in a range that does not impair the properties, depending on the binder component to be used, and is preferably 0.005 parts by mass to 1.0 parts by mass with respect to 100 parts by mass of the hydraulic component. Part by mass, more preferably 0.01 part by mass to 0.75 part by mass, still more preferably 0.05 part by mass to 0.5 part by mass, and particularly preferably 0.1 part by mass to 0.00 part by mass. 4 parts by mass.

  When the content of the water reducing agent is too small, it is difficult to obtain a suitable effect (excellent fluidity and good compressive strength). Even if the content of the water reducing agent is too much, it is difficult to obtain an effect commensurate with the amount added, which is not only uneconomical, but in some cases the viscosity increases and the amount of kneading water increases to obtain the required fluidity. There is a case.

  The self-leveling material of this embodiment preferably contains a thickener in order to suppress the separation of the material and obtain a cured body having good surface properties. The thickener is preferably a methylcellulose thickener. The methylcellulose thickener can be used regardless of its type, and it is particularly preferable to use a hydroxyethylmethylcellulose thickener or a hydroxypropylmethylcellulose thickener. When the thickener is a methylcellulose-based thickener, it is possible to suppress separation of hydraulic components and fine aggregates, suppress generation of bubbles, and improve the surface properties of the cured body.

  The viscosity of the thickener is preferably 400 mPa · s to 500000 mPa · s, more preferably 1000 mPa · s to 100000 mPa · s, still more preferably 2000 mPa · s to 50000 mPa · s, and particularly preferably 3000 mPa · s. s to 40,000 mPa · s.

  In the present specification, “viscosity” refers to a viscosity obtained by measuring a 2% by mass aqueous solution of a thickener at 20 ° C. using a B-type viscometer. The type and rotation speed of the rotor when measuring the viscosity can be appropriately selected from combinations determined by the viscometer used.

  The content of the thickener is preferably 0.01 parts by mass to 0.80 parts by mass, more preferably 0.02 parts by mass to 0.70 parts by mass with respect to 100 parts by mass of the hydraulic component. More preferably, it is 0.04 mass part-0.60 mass part, Most preferably, it is 0.06 mass part-0.50 mass part. When the content of the thickener is in the above range, the material is difficult to separate, excellent fluidity is obtained, and a cured body with better surface properties can be obtained.

  The self-leveling material of this embodiment preferably contains a setting retarder in order to ensure the fluidity retention of the self-leveling mortar obtained by kneading the self-leveling material and water.

  A well-known thing can be used as a setting retarder. Specific examples of the setting retarder include, for example, organic acids such as oxycarboxylic acids, sugars such as glucose, maltose, and dextrin, sodium bicarbonate, sodium phosphate and the like alone or in combination of two or more components. Can be used.

  Oxycarboxylic acids include oxycarboxylic acids and their salts. Examples of oxycarboxylic acid include citric acid, gluconic acid, tartaric acid, glycolic acid, lactic acid, hydroacrylic acid, α-oxybutyric acid, glyceric acid, tartronic acid, malic acid and other aliphatic oxyacids, salicylic acid, m-oxy Mention may be made of aromatic oxyacids such as benzoic acid, p-oxybenzoic acid, gallic acid, mandelic acid and tropic acid.

  Examples of the salt of oxycarboxylic acid include alkali metal salts (specifically sodium salt and potassium salt) and alkaline earth metal salts (specifically calcium salt, barium salt and magnesium salt). Sodium salts are more preferably used. In particular, sodium tartrate is preferred from the standpoint of setting delay effect, availability, and price, and more preferably used in combination with sodium bicarbonate.

  The content of the setting retarder is preferably 0.10 parts by mass to 2.0 parts by mass, and more preferably 0.20 parts by mass to 1.5 parts by mass with respect to 100 parts by mass of the hydraulic component. More preferably, it is 0.30 mass part-1.2 mass part, Most preferably, it is 0.40 mass part-1.0 mass part. When the content of the setting retarder is within the above-mentioned preferable range, the fluidity can be further improved and a suitable fluidity retention time can be obtained.

  The self-leveling material of the present embodiment preferably contains a curing accelerator in order to ensure excellent quick curing even at low temperatures. Moreover, in order to obtain excellent quick hardening while maintaining fluidity, the curing accelerator preferably contains a lithium salt.

  Examples of lithium salts include, for example, inorganic lithium salts such as lithium carbonate, lithium chloride, lithium sulfate, lithium nitrate, and lithium hydroxide, and lithium oxalate, lithium acetate, lithium tartrate, lithium malate, and lithium citrate. An organic acid organic lithium salt can be mentioned. In particular, lithium carbonate is preferable from the viewpoint of curing acceleration effect, availability, and price.

  As the curing accelerator, those having a particle size that does not interfere with the properties of the self-leveling material are preferably used, and specifically, a curing accelerator having a particle size of 50 μm or less is preferably used. In particular, when a lithium salt is used, the particle diameter of the lithium salt is preferably 50 μm or less, more preferably 30 μm or less, still more preferably 20 μm or less, and particularly preferably 10 μm or less. If the particle diameter of the lithium salt is larger than the above range, the solubility of the lithium salt may become too small. In particular, in the pigment addition system, it may be noticeable as a large number of fine spots, and the appearance may be impaired.

  The content of the lithium salt as the curing accelerator is preferably 0.01 parts by mass to 2.0 parts by mass, more preferably 0.02 parts by mass to 1.0 parts by mass with respect to 100 parts by mass of the hydraulic component. It is a mass part, More preferably, it is 0.04 mass part-0.5 mass part, Most preferably, it is 0.05 mass part-0.2 mass part.

  As the curing accelerator, in addition to the above, a known component that accelerates curing can be used in combination. For example, an aluminate such as sodium aluminate having a hardening accelerating effect, a sulfate such as aluminum sulfate or potassium sulfate, calcium formate, and calcium chloride can be suitably used, and these are used in combination. Also good.

  The self-leveling material of the present embodiment preferably contains a fatty acid metal salt in order to ensure stable base adhesion strength even in an environment by repeated heating and cooling.

  As the fatty acid metal salt, an aluminum, calcium or zinc salt having 18 or more carbon atoms is preferable, and an aluminum salt is particularly preferable from the viewpoint of rapid hardening.

  The amount of the fatty acid metal salt is preferably 0.1 parts by mass to 2 parts by mass, more preferably 0.2 parts by mass to 1.5 parts by mass, and still more preferably with respect to 100 parts by mass of the hydraulic component. Is 0.3 part by mass to 1.1 parts by mass, and particularly preferably 0.5 part by mass to 1.0 part by mass. If it is less than this, a sufficient effect may not be obtained, and if it is more than this, the cured product properties such as fluidity and compressive strength may be adversely affected.

  The self-leveling material of this embodiment preferably further contains an antifoaming agent as long as the properties of the self-leveling material are not impaired. Thereby, the defoaming effect is acquired and the hardening body excellent in smoothness can be obtained.

  Examples of antifoaming agents include known substances such as synthetic substances such as silicones, alcohols, and polyethers, and natural substances derived from plants. Among these, polyether antifoaming agents are preferably used from the viewpoints of price and availability. Moreover, it can also be used in combination of 2 or more types among these as needed. By using an antifoaming agent, it can be expected that the defoaming effect of the self-leveling material is improved.

  The content of the antifoaming agent is preferably 0.5 to 5.0 parts by mass, more preferably 0.75 to 4.0 parts by mass, and still more preferably 100 parts by mass of the hydraulic component. 1.0 mass part-3.0 mass parts, Especially preferably, they are 1.25 mass parts-2.0 mass parts. By including an antifoamer in the said preferable range, an antifoaming effect becomes easier to obtain.

<Self-leveling mortar>
A self-leveling mortar can be prepared (manufactured) by mixing and stirring the self-leveling material of the present embodiment with a predetermined amount of water. Since the self-leveling mortar has excellent fluidity, a horizontal and flat hardened surface of the floor can be easily formed by applying it to the floor of the structure. When preparing the self-leveling mortar, the fluidity of the self-leveling mortar can be adjusted by adjusting the amount of water.

  In the self-leveling mortar, the mass ratio (W / S) of water (W) to the self-leveling material (S) is preferably 0.18 to 0.28, more preferably 0.19 to 0.26, still more preferably. It can mix | blend and knead | mix so that it may become 0.20-0.24, Most preferably, it is the range of 0.21-0.23.

  There is a flow value (mm) as an index of fluidity of the self-leveling mortar. The flow value is a value (unit: mm) measured in accordance with the Architectural Institute of Japan JASS 15M-103 “Quality Standard for Self-Leveling Material”.

  The flow value of the self-leveling mortar is preferably 215 mm to 250 mm. The flow value of the self-leveling mortar is more preferably 220 mm to 245 mm, still more preferably 225 mm to 240 mm, and particularly preferably 230 mm to 240 mm. When the flow value of the self-leveling mortar is in the above range, more excellent fluidity is realized.

  There is an SL value (mm) as an index of flow retention of the self-leveling mortar. The SL value can be measured using an SL measuring device shown in FIG.

  The SL measuring instrument 10 has a bowl shape with internal dimensions of width 30 mm × height 30 mm × length 750 mm, and only one end is an open end. The SL measuring instrument 10 is provided with a filling part 11 for filling the self-leveling mortar on the closed end side, and a weir plate 12 adjacent to the filling part 11 for damming the self-leveling mortar to be filled. Yes. The internal dimensions of the filling part 11 are 30 mm wide × 30 mm high × 150 mm long.

  FIG. 3 is a cross-sectional view schematically showing a method for measuring the SL value of self-leveling mortar using the above-described SL measuring device 10. First, as shown in FIG. 3A, the self-leveling mortar immediately after kneading is poured so as to fill the filling portion 11. Then, the weir 12 is pulled up after a predetermined time (for example, immediately after pouring (L0), after pouring for 20 minutes (L20), and after pouring for 30 minutes (L30)), ( As shown in b), the poured self-leveling mortar flows out toward the opening end side of the SL measuring device 10.

  The distance from the reference point 13 to the end point 14 where the flow of the self-leveling mortar has stopped is defined as the SL value (mm). By measuring the SL value (L0, L20, and L30) at the predetermined time, the flow retention of the self-leveling mortar can be evaluated.

  The SL value (L0) of the self-leveling mortar is preferably 400 mm to 600 mm, more preferably 450 mm to 600 mm, still more preferably 475 mm to 575 mm, and particularly preferably 500 mm to 550 mm. The SL value (L20) of the self-leveling mortar is preferably 325 mm to 600 mm, more preferably 350 mm to 580 mm, still more preferably 375 mm to 560 mm, and particularly preferably 400 mm to 550 mm. Moreover, the SL value (L30) of the self-leveling mortar is preferably 200 mm to 550 mm, more preferably 250 mm to 530 m, still more preferably 275 mm to 520 mm, and particularly preferably 300 mm to 510 mm. When the SL value is in the above-described range, it has excellent fluidity and fluidity that can obtain an appropriate working time.

<Hard mortar>
A cured mortar can be obtained by curing the self-leveling mortar obtained using the self-leveling material of the present embodiment. Since the self-leveling material of the present embodiment has excellent quick hardening and quick drying properties, a mortar cured body is formed in a short period of time. Therefore, by using the self-leveling material of this embodiment, it is excellent in shortening the work period and can be suitably used as a floor finishing material and a floor base material. The fast hardening index can be expressed by a watering time. The watering time is the time (minutes) taken from the preparation (production) of the self-leveling mortar until the moisture on the surface of the self-leveling mortar disappears. The index of fast hardening can also be expressed by Shore hardness. Shore hardness is the time when 2 hours have passed since self-leveling mortar preparation (manufacturing) and the time when 24 hours have passed (material age 24). It is a value obtained by measuring the surface of the cured mortar with a shore hardness meter.

  The watering time in the 20 ° C. curing of the surface of the self-leveling mortar is preferably 30 minutes to 110 minutes, more preferably 40 minutes to 100 minutes, still more preferably 50 minutes to 90 minutes, and particularly preferably 55 minutes. ~ 80 minutes. By setting the watering time within the above-mentioned preferable range, it is possible to realize excellent fast curing while maintaining an appropriate pot life.

  The shore hardness at the age of 2 hours in the curing at 20 ° C. on the surface of the leveling mortar (hardened body) is preferably 10 or more, more preferably 20 or more, still more preferably 30 or more, and particularly preferably 40. That's it. By setting the Shore hardness within the above-mentioned preferable range, it is possible to realize excellent fast curing.

  The Shore hardness of the surface of the self-leveling mortar (cured body) at a temperature of 20 ° C. when cured at 20 ° C. is preferably 60 or more, more preferably 70 or more, still more preferably 75 or more, and particularly preferably 80 That's it. When the Shore hardness is in the above preferred range, a mortar cured body having a strong surface can be obtained.

  Moreover, the mortar cured body of this embodiment is excellent in the surface finish state, and can be used as a floor finish material and a floor base material. The cured surface state is the degree of pulverization / whitening or unevenness on the surface of the cured body after 24 hours of age, and is determined by visual and tactile sensations. “Good” if there is no pulverization / whitening or unevenness and a good surface state, and “No” if pulverization / whitening or unevenness occurs.

  The cured surface state of the mortar cured body is preferably a good surface state without powdering / whitening or unevenness.

<Concrete floor structure>
A concrete floor structure 1 as shown in FIG. 1 can be obtained using the self-leveling material of the present embodiment. The concrete floor structure 1 is formed by laminating a concrete floor layer 4, a primer layer 3, and a mortar cured body layer 2 made of the above mortar cured body, and can be used as a floor finishing material and a floor base material.

The concrete floor structure 1 is based on JASS 15M-103 “Quality Standards for Self-Leveling Materials” and has a material age of 14 days in a 20 ° C. curing performed by a method using a mortar board defined in JIS A 6916. base adhesive strength is preferably 2N / mm ² or more, more preferably 2.3 N / mm ² or more, still more preferably 2.5 N / mm ² or more, and particularly preferably 2.8 N / mm ² That's it. Thereby, as a concrete floor structure, a structure in which a concrete floor layer, a primer layer, and a mortar hardened body layer are integrated can be realized.

The concrete floor structure 1 preferably has a base adhesive strength of 1.5 N / mm ² or more, more preferably 1.6 N / mm ² in an adhesion stability test performed by a method defined in JIS A 1171. or more, still more preferably 2.0 N / mm ² or more, and particularly preferably 2.5 N / mm ² or more. As a result, as a concrete floor structure, integration of the concrete floor layer, primer layer, and mortar hardened body layer is maintained even in indoor places that are affected by the environment where outdoor and hot and cold repetition occurs, and has excellent weather resistance be able to.

  The concrete floor structure 1 is based on JASS 15M-103 “Quality Standards for Self-Leveling Materials” and has a material age of 14 days in a 20 ° C. curing performed by a method using a mortar board defined in JIS A 6916. The decrease rate (II / I) of the base adhesive strength (II) in the adhesive stability test performed by the method defined in JIS A 1171 with respect to the base adhesive strength (I) is preferably 0.5 or more. Yes, more preferably 0.6 or more, still more preferably 0.7 or more, and particularly preferably 0.8 or more. As a result, as a concrete floor structure, integration of the concrete floor layer, primer layer, and mortar hardened body layer is maintained even in indoor places that are affected by the environment where outdoor and hot and cold repetition occurs, and has excellent weather resistance be able to.

The concrete floor layer 4 in the concrete floor structure 1 is formed by forming a floor of a general concrete structure (building), and the concrete floor layer 4 is formed by directly leveling concrete. In some cases, a concrete floor layer 4 is formed by leveling the upper surface of concrete with mortar close to the properties of the concrete. The concrete floor layer 4 in this specification means these things. The compressive strength (nominal strength) of the concrete floor layer 4 is preferably 20 N / mm ² or more, more preferably 30 N / mm ² or more, further preferably 35 N / mm ² or more, and particularly preferably 40 N / mm ^2. mm ² or more.

  The primer layer 3 in the concrete floor structure 4 is mainly composed of acrylic resin. In the present embodiment, the primer layer 3 can be formed by applying an acrylic resin emulsion on the concrete floor layer 4 and drying it. A commercially available acrylic resin emulsion can be suitably used. As the main component acrylic resin, a styrene / acrylic copolymer resin is preferably used. Here, film formation means that a resin film is formed by evaporating and drying the water in the resin emulsion. It is preferable that the minimum film-forming temperature MFT of the acrylic resin emulsion is 0 ° C. or higher and the glass transition temperature Tg is 0 ° C. or lower.

  The acrylic resin emulsion used for the primer layer 3 is preferably stored in a state of being dispersed in water, and the solid content concentration is preferably 30% by mass to 70% by mass, and 35% by mass to 65% by mass. More preferably, 40 mass%-60 mass% are still more preferable, and 45 mass%-55 mass% are especially preferable. If the solid content is too small relative to water, the cost during transportation and storage increases, and if the solid content is too large, it may be difficult to uniformly disperse in water, and aggregation or precipitation may easily occur.

  The thickness of the primer layer 3 is preferably 5 μm to 200 μm, more preferably 10 μm to 150 μm, still more preferably 15 μm to 100 μm, and particularly preferably 20 μm to 75 μm from the viewpoint of firmly bonding the concrete floor layer 4 and the hardened mortar layer 2. preferable.

  The mortar cured body layer 2 in the concrete floor structure 1 is a layer of a mortar cured body obtained by curing a self-leveling mortar obtained by mixing and stirring the self-leveling material of this embodiment with a predetermined amount of water. It was made.

  The thickness of the mortar cured body layer 2 is preferably 3 mm to 50 mm, more preferably 5 mm to 40 mm, still more preferably 7 mm to 30 mm, and particularly preferably 10 mm to 20 mm from the viewpoint of the finished condition after construction. In this case, since the mortar pouring construction is within an easier range, it is possible to obtain a cured surface with high smoothness.

<Construction method>
The construction method of the concrete floor structure obtained using the self-leveling material of the present embodiment includes a primer construction process for constructing a primer on the top surface of the concrete floor layer, and a primer layer formed by drying and forming the primer. A primer layer forming step, a self-leveling mortar construction step for applying a self-leveling mortar obtained by kneading a self-leveling material and water on the upper surface of the primer layer, and curing the self-leveling mortar to form a cured mortar layer. A mortar cured body layer forming step to be formed.

A primer construction process is a process of constructing (application | coating) the above-mentioned primer (for example, acrylic resin emulsion) on the upper surface of a concrete floor layer. The primer can be applied by appropriately selecting, for example, a trowel, a roller, a deck brush or a brush. The primer may be applied once, or may be applied multiple times (for example, about 2 to 3 times). The coating amount of the primer, in order to stably obtain a good adhesive strength, the resin solid content contained in the ^primer, it is preferable to apply such that the ^{30g / m 2 ~120g / m 2} , 35g / m 2 it is more preferable to apply such that the ~110g / ^{m 2,} more preferably be applied so as to ^{40g / m 2 ~100g / m 2} , so that 45g / ^{m 2} ~90g / m 2 coating It is particularly preferable to do this.

  The primer layer forming step is a step of drying and forming the applied primer. The drying time after the primer application can be appropriately determined according to the temperature condition and ventilation condition, and it is usually preferable to dry for 3 to 8 hours in summer and 5 to 12 hours in winter.

  The self-leveling mortar construction step is a step of constructing (casting) the above-mentioned self-leveling mortar obtained by kneading the above-mentioned self-leveling material and water on the upper surface of the primer layer. The self-leveling mortar can be placed on a floor surface having a horizontal surface or a floor surface having a gradient of more than 0/1000 and not more than 50/1000. As for the leveling mortar that has been placed, the surface of the leveling mortar is made uniform by using scissors and dragonflies.

  A mortar hardening body layer formation process is a process of hardening the above-mentioned self-leveling mortar and forming a mortar hardening body layer. Since the surface of the self-leveling mortar is cured while being made uniform, it is possible to produce a mortar cured body with excellent smoothness.

  The self-leveling mortar layer, depending on the temperature and humidity conditions at the construction site, starts curing within 30 minutes to 2 hours after the completion of the construction (pouring), and the surface hardness increases with the progress of curing, As shown in FIG. 1, it becomes a mortar hardening body layer.

The contents of the present invention will be specifically described below with reference to examples. Note that the present invention is not limited to these examples.

[Materials used]
The materials used in Examples and Comparative Examples are described below.

<Self-leveling material>
(1) Hydraulic component Portland cement [PC] (Hayato Portland cement, manufactured by Ube Mitsubishi Cement Co., Ltd., Blaine specific surface area 4540 cm ² / g)
Alumina cement [AC] (main component: monocalcium aluminate, manufactured by Kerneos, Blaine specific surface area 3060 cm ² / g)
Gypsum [GG] (Natural anhydrous gypsum, Blaine specific surface area 3950 cm ² / g)

The blending ratio of hydraulic components is shown in Table 1.

(2) Blast furnace slag fine powder (Blaine specific surface area 4350 cm ² / g)
(3) Fine aggregate: No. 6 silica sand (coarse fraction having a particle size of more than 0.6 mm = 0.1%, coarse fraction having a particle size of more than 0.3 mm = 23.5%, water absorption = 2.61%)

  Table 2 shows the particle size composition (mass fraction remaining in each sieve, mass fraction remaining between each successive sieve) and coarse grain ratio of the fine aggregate.

(4) Re-emulsifying resin powder Vinyl acetate / acrylic copolymer (MFT = 0 ° C., Tg = 10 ° C.)
(5) Water reducing agent Polycarboxylic acid type water reducing agent (6) Thickener Hydroxyethyl methylcellulose type thickener (Viscosity of 2 mass% aqueous solution at 20 ° C .: 28000 mPa · s, measurement conditions: B-type viscometer, rotational speed 12 rpm , Rotor No. 4)
(7) Antifoaming agent Polyether-based antifoaming agent (8) Setting retarder • Mixture of sodium tartrate and sodium bicarbonate (9) Curing accelerator • Lithium carbonate (average particle size 3.5 μm)

(10) Fatty acid metal salt A: C number 18 aluminum salt B: C number 18 calcium salt C: C number 18 zinc salt

<Primer>
Acrylic resin emulsion (main component: styrene / acrylic copolymer resin, solid content concentration 46% by mass)

<Underground concrete>
As the base plate used for the adhesion test, a mortar plate in accordance with JIS A 6916 was used.

[Preparation of self-leveling material (production)]
For the preparation of the self-leveling material, the above materials (total amount: 15 kg) were mixed at a blending ratio shown in Table 3. The mixing method is to put the fine aggregate, hydraulic component and blast furnace slag fine powder in order into the Eirich mixer container, and then re-emulsified resin powder, water reducing agent, thickener, antifoaming agent, A curing accelerator, a setting retarder and a fatty acid metal salt were added and mixed for 4 minutes. Blast furnace slag fine powder, fine aggregate, re-emulsified resin powder, water reducing agent, thickener, antifoaming agent, curing accelerator, setting retarder and fatty acid metal salt content, hydraulic component 100 parts by mass It is expressed in parts by mass.

[Preparation of self-leveling mortar (production)]
Self-leveling mortar was obtained by adding 330 g of water to 1.5 kg of the self-leveling material shown in Table 3 and kneading for 3 minutes using a chem stirrer. The self-leveling mortar was prepared in a temperature-controlled room at a temperature of 20 ° C.

  The flow value, SL value, watering time of each obtained leveling mortar, shore hardness and cured surface state of the mortar cured body, base adhesion strength, adhesion stability (adhesion strength after repeated aging) are as follows. Obtained. Hereinafter, all the curing accompanying each measurement was performed in a temperature-controlled room at a temperature of 20 ° C.

[Flow value]
The flow value was measured according to JASS 15M-103 “Architectural Institute of Japan: Quality standards for self-leveling materials”. Table 4 shows the flow values of the self-leveling mortar.

[SL value]
The SL value of the self-leveling mortar was measured using the SL measuring device shown in FIG. Measurements were carried out immediately after the adjustment of the self-leveling mortar, 20 minutes after standing and 30 minutes after standing (represented as L0, L20 and L30, respectively). The SL value is shown in Table 4.

[Watering time]
Immediately after preparing the self-leveling mortar, the watering time was poured into a synthetic resin container having an internal dimension of 130 mm width × 190 mm length × 17 mm height to a thickness of 15 mm, and then the surface of the self-leveling mortar as the condensation started. The time until the surface water of the (cured body) disappeared (light reflection was lost and the clouded state) was measured. Table 4 shows the watering time of the surface of the self-leveling mortar (cured body).

[Shore hardness]
For the Shore hardness, measure the surface hardness at any four locations using the spring hardness tester type D type (manufactured by Ueshima Seisakusho Co., Ltd.) after the specified time has elapsed. The average value of the reading values of the spring type hardness tester type D gauge was used. Table 4 shows the shore hardness of the mortar cured body after 2 hours and 24 hours of age.

[Curing surface condition]
After 24 hours had elapsed with respect to the cured body, the properties of the cured surface (surface pulverization / whitening, surface irregularities) were evaluated visually and by palpation. The evaluation judgment is as follows, and the evaluation results are shown in Table 4.
○… Good, ×… There is a problem

[Base adhesion strength]
Base adhesion strength conforms to JASS 15M-103 “Quality standards for self-leveling materials”, and styrene / acrylic diluted 3 times as a primer to a 20 mm thick mortar base plate (a mortar plate defined in JIS A 6916) After coating the copolymer resin emulsion with a solid content of 45 g / m ² (the primer layer thickness is about 40 μm) and drying for one day to form a primer layer, the above mortars are 10 mm thick. The specimen was cured by being cured for 14 days (age 14 days). Molding, curing and measurement of the test body were performed in a constant temperature room at a temperature of 20 ° C. The results are shown in Table 4. Note that the 3-fold diluted solution is a solution obtained by adding 2 water to the styrene / acrylic copolymer resin emulsion 1 in terms of mass ratio.

[Adhesion stability]
The adhesion stability test (base adhesion strength after repeated aging) conforms to the method specified in JIS A 1171 and is used as a primer on a mortar base plate having a thickness of 20 mm (a mortar plate specified in JIS A 6916). A styrene / acrylic copolymer resin emulsion diluted by a factor of ² was applied in a solid content of 45 g / m ² (the thickness of the primer layer was about 40 μm) and dried for one day to form a primer layer. The self-leveling mortar was poured to a thickness of 10 mm, cured for 2 days at 20 ° C. in wet air, demolded, cured in water at 20 ° C. for 5 days, and further cured at 20 ° C. and 65% humidity for 21 days (age) The test piece was cured after 28 days). This was covered with an epoxy resin on the three sides of the test specimen 3 days before the end of curing, and after the completion of the curing, the specified heating / cooling cycle was repeated 10 times. The measurement was performed in a constant temperature room at a temperature of 20 ° C. The results are shown in Table 4.

  As shown in Table 4, Examples 1 to 5 showed excellent fluidity with flow values of 220 mm to 240 mm and SL values of 400 mm to 60 mm. In Examples 1 to 5, the watering time was 70 minutes to 100 minutes, and the surface hardness was 30 or more in 2 hours and 80 or more in 24 hours, which showed excellent rapid hardness. In particular, Examples 1 to 3 showed a faster hardening property with a watering time of 70 minutes to 80 minutes and a surface hardness of 40 or more at 2 hours. Moreover, there was no powdering / whitening or unevenness on the cured surface. Thereby, the cured surface state is also excellent.

Moreover, Examples 1-5 were excellent also in the adhesive strength (base adhesive strength) with base mortar, and were ^2.5 N / mm < ² > or more. Further, in Examples 1 to 5, the base adhesive strength (adhesion stability) after repeated heating and cooling was 1.5 N / mm ² or more, and the decrease rate with respect to the base adhesive strength (base adhesive strength B after repeated heating and cooling / base The adhesive strength A) was also as high as 0.5 or more. In particular, in Examples 1, 2, 4, and 5, the base adhesion strength (adhesion stability) after repeated heating and cooling was 2.0 N / mm ² or more, and the decrease rate with respect to the base adhesive strength (the base after repeated heating and cooling). Adhesive strength B / base adhesive strength A) was also very good at 0.7 or more.

DESCRIPTION OF SYMBOLS 1 ... Concrete floor structure 2 ... Hardened mortar layer 3 ... Primer layer 4 ... Concrete floor layer 10 ... SL measuring device 11 ... Filling part 12 ... Dam plate 13 ... Marking point 14 ... End point

Claims (5)

A self-leveling material containing a hydraulic component, blast furnace slag fine powder, fine aggregate, re-emulsified resin powder, water reducing agent, thickener, curing accelerator, setting retarder and fatty acid metal salt,
The hydraulic component includes 15% to 45% by weight of Portland cement, 35% to 65% by weight of alumina cement, and 20% to 40% by weight of gypsum,
Content of the said re-emulsification resin powder is 1-15 mass parts with respect to 100 mass parts of said hydraulic components,
The content of the blast furnace slag fine powder is 40 parts by mass to 120 parts by mass with respect to 100 parts by mass of the hydraulic component,
The content of the fine aggregate is 80 parts by mass to 200 parts by mass with respect to 100 parts by mass of the hydraulic component,
The curing accelerator comprises a lithium salt;
The lithium salt content is 0.01 parts by mass to 2.0 parts by mass with respect to 100 parts by mass of the hydraulic component,
A self-leveling material in which the content of the fatty acid metal salt is 0.1 to 2 parts by mass with respect to 100 parts by mass of the hydraulic component.   The self-leveling material according to claim 1, wherein the fatty acid metal salt is an aliphatic aluminum, calcium or zinc salt having 18 or more carbon atoms.   The self-leveling material according to claim 1 or 2, wherein a main component of the re-emulsifying resin powder is a vinyl acetate / acrylic copolymer.   The coarse aggregate ratio of the fine aggregate is 0.60 to 1.40, the water absorption is 3.0% or less, and the mass fraction of the fine aggregate remaining at a sieve opening of 0.3 mm is 5.0. The self-leveling material according to any one of claims 1 to 3, wherein the leveling material is% to 50%. A primer layer mainly composed of an acrylic resin provided on the concrete floor layer;
A cured body layer comprising the self-leveling material according to any one of claims 1 to 4, provided on the primer layer;
A concrete floor structure comprising:

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