Water-based release agent composition

Abstract

To provide an aqueous release agent composition in which storage stability is compatible with releasability, and a method for producing the hardened body of a hydraulic composition.SOLUTION: An aqueous release agent composition comprises: (A) a nonionic detergent (hereinafter, referred as an (A) component) in which an HLB value calculated by a Griffin method is 5.0 or more to 13.0 or less by 7 or more to 90 or less mass%; (B) an oily component (hereinafter referred as a (B) component; and water (C) (hereinafter referred as a (C) component), and the mass ratio between the content of the (A) component and the content of the (B) component, (A) / (B) is 1 or more to 10 or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an aqueous mold release agent composition and a method for producing a cured body of a hydraulic composition using the same.

Background Art

[0002] Many industrial products typified by concrete, ceramics, plastics, resins, and foods are manufactured by a process in which an uncured curable composition is filled into a mold, and then cured by drying or a chemical reaction in a subsequent process to obtain a cured body. Therefore, in order to ship the above industrial products, a process called "demolding" for removing the cured body from the mold is required. In order to facilitate the demolding process and improve productivity, in this industrial field, process chemicals called "mold release agents" or "release agents" (hereinafter collectively referred to as mold release agents) are used. Generally, mold release agents are formulated with oils having low surface tension or surfactants that reduce surface tension in order to reduce the adhesion between the mold and the curable composition. They are roughly classified into oil-based mold release agents composed of oily components and surfactants, and aqueous mold release agents that further contain water.

[0003] As an aqueous mold release agent, for example, Patent Document 1 discloses an emulsion-type mold release agent for concrete molds, which is characterized by comprising a petroleum resin, a petroleum-based hydrocarbon oil, water, and a surfactant. Further, Patent Document 2 discloses a mixed oil or mineral oil of 12 to 40% by weight, which is solid or semi-solid at room temperature as a base oil and is a combination of an oil and fat having an elevated melting point (by the standard oil and fat analysis test method) of 20 to 60°C and an oil and fat that is liquid at room temperature, 1.0 to 7% by weight of a nonionic surfactant in which nonionic surfactants having different HLB values are mixed and the HLB is adjusted to 6.0 to 14.0 as an emulsifier, 0.3 to 6% by weight of a cationic surfactant as an emulsification aid and an oil film strengthening agent, 0.2 to 6% by weight of a cyclic amine ethoxylate as a water-displacing rust inhibitor, with the balance being water to make 100% by weight, and the composition is subjected to a dispersion treatment with a homogenizer to be made into fine particles of 0.1 to 10 μm. An O / W emulsion-type concrete mold release agent composition is disclosed. Further, Patent Document 3 discloses a water-soluble solvent release agent characterized in that an oil group having dispersibility in water due to a surfactant is blended in a proportion of 2 to 10 wt% based on the total amount, and a water-soluble polymer is blended in a proportion of 0.01 to 10 wt% based on the total amount, and then diluted with water.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Disclosure of the Invention

Problems to be Solved by the Invention

[0005] Since general release agents are applied to a mold by spray spraying or coating, oils with a low viscosity, that is, oils with a relatively low number of carbon atoms and high flammability, are often used from the viewpoints of sprayability and workability. In addition, since many aqueous release agents lack product stability (one-component stability) in a water-containing system, water is blended immediately before use and adjusted and used as an emulsion, so they are stored in a highly flammable form and are subject to storage restrictions.

[0006] The present invention provides an aqueous release agent composition that achieves both storage stability and release properties, and a method for producing a cured body of a hydraulic composition using the same.

Means for Solving the Problems

[0007] The present invention relates to an aqueous release agent composition containing (A) a nonionic surfactant having an HLB value calculated by the Griffin method of 5.0 or more and 13.0 or less (hereinafter referred to as component (A)) in an amount of 7% by mass or more and 90% by mass or less, (B) an oily component (hereinafter referred to as component (B)), and (C) water (hereinafter referred to as component (C)) in an amount of 10% by mass or more and 90% by mass or less, and having a mass ratio (A) / (B) of the content of component (A) to the content of component (B) of 1 or more and 10 or less.

[0008] The present invention also relates to a method for producing a cured body of a hydraulic composition, including the following steps 1 to 4. Step 1: A step of kneading water and hydraulic powder to obtain a hydraulic composition. Step 2: A step of filling the hydraulic composition obtained in Step 1 into a mold coated or sprayed with the aqueous release agent composition of the present invention. Step 3: A step of curing the hydraulic composition filled in the mold obtained in Step 2. Step 4: A step of demolding the cured body obtained in Step 3 from the mold.

Effects of the Invention

[0009] According to the present invention, there are provided an aqueous release agent composition that achieves both storage stability and releasability, and a method for producing a cured body of a hydraulic composition using the same. In recent years, the SDGs "Sustainable Development Goals" have been proposed for the realization of a sustainable society. The aqueous release agent composition of the present invention and the method for producing a cured body of a hydraulic composition using the same can achieve reduction of waste by improving the productivity and storage stability of the curable composition, and can be a technology that contributes to, for example, SDGs No. 7, 8, 9, 11, 12, etc.

Embodiments for Carrying Out the Invention

[0010] The present inventors have found that an aqueous release agent composition excellent in storage stability and releasability can be obtained by containing a nonionic surfactant having a specific HLB value as component (A) and an oily component as component (B) in a specific ratio. Although the mechanism by which the aqueous mold release agent composition of the present invention is excellent in storage stability and mold release property is not necessarily clear, it is presumed as follows. When a surfactant is contained in an aqueous mold release agent composition containing an oily component and water, the surfactant improves the stability of the emulsion by reducing the oil-water interfacial tension. However, it is presumed that the surfactant also elutes into the bulk of the hydraulic composition filled in the mold, reducing the surface tension, and as a result, enhancing the affinity between the mold and the hydraulic composition and promoting adhesion to the mold. However, in the aqueous mold release agent composition of the present invention, since a one-component transparent aqueous mold release agent can be obtained by containing a nonionic surfactant having a specific HLB value in an appropriate ratio with the oily component, it is considered that a microemulsion having a smaller micelle diameter than an emulsion is formed. In the microemulsion system, the micelle surface area is much larger than that of the normal emulsion system, and it is presumed that most of the surfactant exists at the oil-water interface. Thereby, it is considered that the elution of the surfactant into the bulk of the hydraulic composition filled in the mold is suppressed, and both storage stability and mold release property are achieved.

[0011] [Aqueous mold release agent composition] <Component (A)> The aqueous mold release agent composition of the present invention contains, as component (A), a nonionic surfactant having an HLB value calculated by the Griffin method of 5.0 or more and 13.0 or less. The HLB of component (A) is determined by the Griffin method represented by the following general formula (1) in the case of a nonionic surfactant having a polyoxyalkylene group. HLB value = [((molecular weight of the polyoxyalkylene group portion of component (A)) / (molecular weight of component (A))) × 20] (1) The molecular weight of the polyoxyalkylene group portion of component (A) shall be calculated using the value of the average addition mole number of the polyoxyalkylene group. For nonionic surfactants for which the HLB cannot be determined by the Griffin method, the HLB value determined by experiment shall be adopted. The experimental method shall be the method described on page 319 of the "Surfactant Handbook", published by Sangyo Tosho Co., Ltd., edited by Ichiro Nishi, 5th edition, January 10, 1966.

[0012] (A) component's HLB, from the perspective of mold release property, is 5.0 or more, preferably 6.0 or more, more preferably 7.0 or more, still more preferably 8.0 or more, even more preferably 8.5 or more, and from the perspective of mold release property, is 13.0 or less, preferably 12.0 or less, more preferably 11.0 or less, still more preferably 10.5 or less.

[0013] (A) component is preferably a nonionic surfactant represented by the following general formula (a1) from the perspective of storage stability. R 1a (CO) m O-(AO) n -R 2a (a1) [In the formula, R 1a is an aliphatic hydrocarbon group having 8 to 20 carbon atoms, R 2a is a hydrogen atom or a methyl group. CO is a carbonyl group, m is a number of 0 or 1. The AO group is an alkyleneoxy group having 2 to 4 carbon atoms containing an ethyleneoxy group. n is the average number of moles added, and is a number of 1 or more and 15 or less. ]

[0014] In the general formula (a1), R 1a is preferably 10 or more, more preferably 12 or more, still more preferably 14 or more from the perspective of storage stability, and is preferably an aliphatic hydrocarbon group of 18 or less, more preferably 16 or less, preferably an alkyl group or an alkenyl group from the perspectives of storage stability and mold release property. In the general formula (a1), m is a number of 0 or 1, and is preferably 1. In the general formula (a1), the AO group is an alkyleneoxy group having 2 to 4 carbon atoms including an ethyleneoxy group, preferably an alkyleneoxy group having 2 to 3 carbon atoms including an ethyleneoxy group, and more preferably an ethyleneoxy group. The AO group may be an alkyleneoxy group containing an ethyleneoxy group and another alkyleneoxy group, for example, a propyleneoxy group. The other alkyleneoxy group is preferably a propyleneoxy group. When the AO group contains an ethyleneoxy group and a propyleneoxy group, the ethyleneoxy group and the propyleneoxy group may be in a block type bond or a random type bond. The ethyleneoxy group makes the HLB value higher than that of the propyleneoxy group. In the general formula (a1), n is the average number of moles added, and from the viewpoint of storage stability, it is preferably 3 or more, more preferably 4 or more, still more preferably 5 or more, and from the viewpoint of storage stability, it is preferably 13 or less, more preferably 11 or less, still more preferably 9 or less.

[0015] <(Component B)> The aqueous release agent composition of the present invention contains an oily component as the (B) component. Examples of the (B) component include (1) mineral oils such as kerosene, light oil, spindle oil, transformer oil, and machine oil, (2) synthetic oils such as polyalkylene glycol, (3) vegetable oils such as rapeseed oil, coconut oil, palm oil, and soybean oil, (4) fats and oils, and (5) fatty acid esters. One or more selected from these may be mentioned. From the viewpoint of releasability, the (B) component is preferably a mineral oil, more preferably one or more mineral oils selected from kerosene, light oil, spindle oil, transformer oil, and machine oil, and still more preferably one or more mineral oils selected from spindle oil and machine oil.

[0016] Commercially available products can be used as the (B) component. When spindle oil is used as the (B) component, examples of the spindle oil include Cosmo Pure Spin E and Cosmo Pure Spin ESP (both manufactured by Cosmo Oil Lubricants Co., Ltd.), and Cosmo Pure Spin ESP is preferred. When using machine oil as the (B) component, examples of the machine oil include Cosmo Pure Safety 10, Cosmo Pure Safety 22, Cosmo Pure Safety 32, Cosmo Pure Safety 46, and Cosmo Pure Safety 68 (all manufactured by Cosmo Oil Lubricants Co., Ltd.).

[0017] <(C) component> The aqueous release agent composition of the present invention contains water as the (C) component. As the water, ion-exchanged water, distilled water, sterilized purified water, or tap water can be used.

[0018] <Composition, etc.> The aqueous release agent composition of the present invention contains the (A) component in an amount of 7% by mass or more, preferably 10% by mass or more, more preferably 15% by mass or more, still more preferably 25% by mass or more, even more preferably 30% by mass or more, and even more preferably 40% by mass or more from the viewpoints of storage stability and release property, and 90% by mass or less, preferably 85% by mass or less, more preferably 80% by mass or less, still more preferably 70% by mass or less, even more preferably 65% by mass or less, and even more preferably 60% by mass or less from the viewpoint of storage stability.

[0019] The aqueous release agent composition of the present invention contains the (B) component in an amount of preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more from the viewpoint of release property, and preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 40% by mass or less, even more preferably 35% by mass or less, and even more preferably 30% by mass or less from the viewpoint of release property.

[0020] In the aqueous release agent composition of the present invention, the mass ratio (A) / (B) of the content of the (A) component to the content of the (B) component is 1 or more, preferably 2 or more, more preferably 2.3 or more from the viewpoint of storage stability, and 10 or less, preferably 9.5 or less, more preferably 9 or less from the viewpoint of release property.

[0021] In the aqueous release agent composition of the present invention, the content of component (C) is 10% by mass or more, preferably 20% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, from the viewpoint of the surface appearance of the cured product, and 90% by mass or less, preferably 80% by mass or less, more preferably 70% by mass or less, still more preferably 60% by mass or less, from the viewpoint of releasability.

[0022] In the aqueous release agent composition of the present invention, the mass ratio (B) / (C) of the content of component (B) to the content of component (C) is preferably 0.01 or more, more preferably 0.05 or more, still more preferably 0.1 or more, even more preferably 0.3 or more, from the viewpoint of releasability, and preferably 5 or less, more preferably 4 or less, still more preferably 3 or less, even more preferably 2 or less, even more preferably 1 or less, from the viewpoint of the surface appearance of the cured product.

[0023] The aqueous release agent composition of the present invention may contain a surfactant other than component (A), but its content is limited from the viewpoint of not impairing the effects of the present invention. In the aqueous release agent composition of the present invention, the mass ratio [(A) / total surfactant] of the content of component (A) to the content of the total surfactant is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, even more preferably 95% by mass or more, and 100% by mass or less, and may be 100% by mass, from the viewpoint of not impairing the effects of the present invention.

[0024] The aqueous release agent composition of the present invention may contain a nonionic surfactant other than component (A), but its content is limited from the viewpoint of not impairing the effects of the present invention. In the aqueous release agent composition of the present invention, the mass ratio [(A) / total nonionic surfactant] of the content of component (A) to the content of the total nonionic surfactant is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, even more preferably 95% by mass or more, and 100% by mass or less, and may be 100% by mass, from the viewpoint of not impairing the effects of the present invention.

[0025] In the aqueous release agent composition of the present invention, the absorbance (Abs.) at a wavelength of 660 nm measured by an ultraviolet-visible spectrophotometer is 0 or more, and preferably 1.5 or less, more preferably 0.5 or less, still more preferably 0.2 or less, even more preferably 0.1 or less, even more preferably 0.08 or less, and even more preferably 0.05 or less, from the viewpoint of storage stability. The absorbance (Abs.) is measured using an ultraviolet-visible spectrophotometer (for example, UV-160A manufactured by Shimadzu Corporation) with distilled water as a blank at a fixed wavelength of 660 nm. The aqueous release agent composition of the present invention contains a microemulsion having a smaller micelle diameter than an emulsion. Since the emulsion diameter is small, the absorbance is small, and it has excellent one-component stability (phase stability). Here, since an emulsion scatters light, the larger the emulsion diameter and the higher the emulsion concentration, the greater the absorbance. Therefore, it can be said that the smaller the absorbance, the better the one-component stability (phase stability), because the larger the emulsion diameter and the higher the emulsion concentration, the easier it is for coalescence and delamination to occur.

[0026] The aqueous release agent composition of the present invention may contain, as other components, an antifoaming agent, an antioxidant, a preservative, a metal sequestering agent, and a solvent (excluding components (A) and (B)).

[0027] In addition to application with a brush or a mop, the aqueous release agent composition of the present invention may be applied to a mold by spraying with a spray. These release agents can also be used as lubricating oils. The application amount or spraying amount of the aqueous release agent composition of the present invention to a mold is preferably 0.5 g / m 2 or more, more preferably 1 g / m 2 or more, still more preferably 1.5 g / m 2 or more, and preferably 40 g / m 2 or less, more preferably 38 g / m 2 or less, still more preferably 36 g / m 2 or less.

[0028] The aqueous release agent composition of the present invention is intended for hydraulic compositions, more specifically, mortar compositions or concrete compositions.

[0029] The hydraulic composition contains hydraulic powder, and the hydraulic powder is a powder having physical properties that harden by a hydration reaction, and examples thereof include cement and gypsum. Examples of the cement include ordinary Portland cement, early-strength Portland cement, ultra-early-strength Portland cement, sulfate-resistant Portland cement, low-heat Portland cement, white Portland cement, and eco-cement (for example, JIS R5214, etc.). Among these, cement selected from ordinary Portland cement, sulfate-resistant Portland cement, and white Portland cement is preferable, and ordinary Portland cement is more preferable.

[0030] In addition, the hydraulic powder such as cement may contain powders having pozzolanic action and / or latent hydraulicity such as blast furnace slag, fly ash, and silica fume, and stone powder (calcium carbonate powder), etc. For example, blast furnace slag cement, fly ash cement, silica fume cement, etc. may be used.

[0031] From the viewpoints of productivity and strength, the water / hydraulic powder ratio [the mass ratio of water to hydraulic powder in the slurry (mass of water / mass of hydraulic powder × 100), usually abbreviated as W / P.] is preferably 10% or more, more preferably 15% or more, still more preferably 20% or more, even more preferably 30% or more, and preferably 60% or less, more preferably 55% or less, still more preferably 50% or less can be used.

[0032] The hydraulic composition may further contain aggregates. Examples of the aggregates include fine aggregates and coarse aggregates. The fine aggregates are preferably mountain sand, land sand, river sand, and crushed sand, and the coarse aggregates are preferably mountain gravel, land gravel, river gravel, and crushed stone. Depending on the application, lightweight aggregates may be used. The term "aggregate" is based on "General Concrete Handbook" (issued by Technical Bookstore on June 10, 1998).

[0033] The aggregate can be used within the normal range used for the preparation of concrete, mortar, etc. When the hydraulic composition is concrete, from the viewpoint of the properties of the concrete, the amount of coarse aggregate used is preferably 50% or more, more preferably 55% or more, still more preferably 60% or more, and preferably 100% or less, more preferably 90% or less, still more preferably 80% or less by volume. Also, when the hydraulic composition is concrete, the amount of fine aggregate used is preferably 500 kg / m 3 or more, more preferably 600 kg / m 3 or more, still more preferably 700 kg / m 3 or more, and preferably 1000 kg / m 3 or less, more preferably 900 kg / m 3 or less, from the viewpoint of improving the filling property into the formwork, etc. When the hydraulic composition is mortar, the amount of fine aggregate used is preferably 800 kg / m 3 or more, more preferably 900 kg / m 3 or more, still more preferably 1000 kg / m 3 or more, and preferably 2000 kg / m 3 or less, more preferably 1800 kg / m 3 or less, still more preferably 1700 kg / m 3 or less.

[0034] The hydraulic composition can further contain other components in addition to the above components. For example, a dispersant, an antifoaming agent, an AE agent, a retarder, a foaming agent, a thickener, a blowing agent, a waterproof agent, a fluidizing agent, an early strength agent, etc. can be mentioned. Examples of the early strength agent include compounds selected from hydrochlorides, sulfates, nitrates, nitrites, cyanates, thiocyanates, thiosulfates, and formates of alkali metals and alkaline earth metals, or organic compounds selected from alkanolamines, glycerin derivatives, formaldehyde derivatives, and catechol derivatives, and nanoparticles of hydration products (C-S-H and calcium hydroxide) of Portland cement.

[0035] [Method for producing an aqueous release agent composition] The manufacturing method of the aqueous release agent composition of the present invention is a method for manufacturing the aqueous release agent composition. That is, the present invention is a method for manufacturing an aqueous release agent composition in which component (A), component (B), and component (C) are mixed with a mass ratio (A) / (B) of the mixing amount of component (A) to the mixing amount of component (B) being 1 or more and 10 or less. In the manufacturing method of the aqueous release agent composition of the present invention, the matters described in the aqueous release agent composition of the present invention can be appropriately applied. Component (A), component (B), component (C), and other components are the same as the embodiments described in the aqueous release agent composition of the present invention. In the manufacturing method of the aqueous release agent composition of the present invention, the mixing amount and mass ratio of each component can be applied by substituting the content and mass ratio of each component described in the aqueous release agent composition of the present invention from the content to the mixing amount.

[0036] [Method for manufacturing a hardened body of a hydraulic composition] The manufacturing method of the hardened body of the hydraulic composition of the present invention is a method for manufacturing a hardened body of a hydraulic composition including the following steps 1 to 4. Step 1: A step of kneading water and hydraulic powder to obtain a hydraulic composition. Step 2: A step of filling the hydraulic composition obtained in Step 1 into a mold coated or sprayed with the aqueous release agent composition of the present invention. Step 3: A step of curing the hydraulic composition filled in the mold obtained in Step 2. Step 4: A step of demolding the hardened body obtained in Step 3 from the mold. In the manufacturing method of the hardened body of the hydraulic composition of the present invention, the matters described in the aqueous release agent composition of the present invention and its manufacturing method can be appropriately applied.

[0037] In Step 1, the embodiments described in the above-mentioned hydraulic composition can be appropriately applied. In Step 1, the content of each component in the above-mentioned hydraulic composition can be read as the mixing amount and applied.

[0038] In Step 2, the aqueous release agent composition of the present invention may be applied to the mold by spraying in addition to application with a brush or a mop. These release agents can also be used as lubricating oils. Also, from the viewpoints of mold release property and surface appearance, the coating amount or spraying amount of the aqueous mold release agent composition of the present invention on the mold is preferably 0.5 g / m 2 or more, more preferably 1 g / m 2 or more, still more preferably 1.5 g / m 2 or more, and preferably 40 g / m 2 or less, more preferably 38 g / m 2 or less, still more preferably 36 g / m 2 or less. In addition, as a method for filling the mold with the hydraulic composition, there are methods such as directly charging the hydraulic composition from a mixer and introducing the hydraulic composition into the mold by pumping it with a pump.

[0039] In Step 3, the hydraulic composition filled in the mold obtained in Step 2 is cured. In Step 3, for example, as the curing conditions, the time during which the hydraulic composition is maintained at a curing temperature of 50°C or higher is preferably 1 hour or more, and preferably 24 hours or less, more preferably 20 hours or less. When curing the hydraulic composition filled in the mold by maintaining it at 50°C or higher, it can be carried out by autoclave curing or heating curing such as steam. Also, in Step 3, the hydraulic composition may be cured without steam curing. When manufacturing a mortar or concrete product without steam curing, the time from when water contacts the cement in the preparation of the hydraulic composition to demolding is preferably 4 hours or more and 48 hours or less from the viewpoints of productivity and strength. In this case, the temperature is preferably 0°C or higher, more preferably 5°C or higher, and preferably 45°C or lower, more preferably 40°C or lower. Heating and / or cooling within this temperature range can be appropriately carried out.

[0040] In Step 4, the cured body obtained in Step 3 is demolded from the mold. Steps 3 and 4 can be continuously carried out under a series of temperature controls. Demolding of the cured body can conform to a known method. In the present invention, the time from the start of preparation of the hydraulic composition to demolding, that is, the time from bringing water into contact with the cement to starting demolding, is preferably 4 hours or more, more preferably 5 hours or more, and preferably 48 hours or less, more preferably 40 hours or less, from the viewpoints of productivity and strength.

[0041] The hardened body of the hydraulic composition obtained by the method for producing a hardened body of the hydraulic composition of the present invention is suitable for high-fluidity concrete, non-segregating underwater concrete, lightweight high-fluidity concrete, permeable concrete, in-place lining method (ECL method), and SENS method.

Examples

[0042] (A) component, (B) component, and (C) component were the following.

[0043] <(A) component> ·a-1: Polyoxyethylene lauryl ether, Emulgen 102KG, manufactured by Kao Corporation, HLB value: 6.3 ·a-2: Polyoxyethylene lauryl ether, Emulgen 106, manufactured by Kao Corporation, HLB value: 10.5 ·a-3: Polyoxyethylene oleyl ether, Emulgen 404, manufactured by Kao Corporation, HLB value: 8.8 ·a-4: Polyoxyethylene oleyl ether, Emulgen 408, manufactured by Kao Corporation, HLB value: 10.0 ·a-5: Polyoxyethylene sorbitol tetraoleate, Emulgen 430V, manufactured by Kao Corporation, HLB value: 10.5 ·a-6: Polyoxyethylene alkyl ether, Emulgen 705, manufactured by Kao Corporation, HLB value: 10.5 ·a-7: Polyoxyethylene alkyl ether, Emulgen 707, manufactured by Kao Corporation, HLB value: 12.1 ·a-8: Polyoxyalkylene alkyl ether, Emulgen LS-106, manufactured by Kao Corporation, HLB value: 12.5

[0044] <(A’) component (comparative component of (A) component)> ·a'-1: Polyoxyethylene lauryl ether, Emulgen 109P, manufactured by Kao Corporation, HLB value: 13.6 ·a'-2: Polyoxyethylene alkyl ether, Emulgen 1108, manufactured by Kao Corporation, HLB value: 13.5 ·a'-3: Sorbitan monooleate, Leodol SP-O10V, manufactured by Kao Corporation, HLB value: 4.3

[0045] <(Component B)> ·b-1: Cosmo Pure Safety 68, manufactured by Cosmo Oil Lubricants Co., Ltd. ·b-2: Cosmo Pure Spin E, manufactured by Cosmo Oil Lubricants Co., Ltd. <(Component C)> · Tap water: Specific gravity: 1.00, Wakayama City, Wakayama Prefecture

[0046] (1) Method for preparing the aqueous release agent composition The above components were added to a 50 mL vial so as to have the contents shown in Table 1, and the mixture was vigorously inverted and mixed at 20°C to prepare each aqueous release agent composition.

[0047] (2) Method for evaluating one-liquid stability Each aqueous release agent composition prepared by the method described in (1) was stored at 20°C for 1 week, then 3 mL was filled into a disposable cell, and the absorbance (Abs.) at a fixed wavelength of λ = 660 nm was measured using an ultraviolet-visible spectrophotometer UV-160A (manufactured by Shimadzu Corporation) with distilled water as a blank, and used as an index for one-liquid stability. Here, since the emulsion scatters light, the larger the emulsion diameter and the higher the emulsion concentration, the larger the absorbance. The larger the emulsion diameter and the higher the emulsion concentration, the easier it is for coalescence and separation to occur. Therefore, it can be said that the smaller the absorbance, the better the one-liquid stability (phase stability). When layer separation occurred due to storage, it was vigorously stirred beforehand and degassed by sonication, and then the absorbance measurement was performed. The results are shown in Table 1.

[0048] (3) Mold adjustment (1) Each aqueous release agent composition adjusted by the described method was applied to a cylindrical steel mold (height 10 cm, inner diameter 5 cm) using a brush.

[0049] (4) Adjustment of the uncured curable composition Mortar was adjusted according to the formulation shown in Table 2. The mortar was prepared by adding an aqueous solution of water and a cement dispersant to a mixture of cement and sand, and kneading at 62 rpm for 120 seconds using a mortar mixer specified in JIS R5201. As the cement dispersant, Mytei 21VS (manufactured by Kao Corporation) was used, and the addition amount of the cement dispersant was adjusted so that the mortar flow was 250 ± 10 mm using a flow cone (upper diameter 70 mm × lower diameter 100 mm × height 60 mm) described in JIS R 5201. In each of the examples and comparative examples, the amount was 0.13 parts by mass as the effective solid content per part by mass of the powder.

[0050] The components used for the preparation of the mortar are as follows. · Cement: A 1:1 (mass ratio) mixture of ordinary Portland cement manufactured by Taiheiyo Cement Corporation and ordinary Portland cement manufactured by Sumitomo Osaka Cement Co., Ltd., specific gravity 3.16 · Sand: From Joho, Kyoto Prefecture, surface-dry specific gravity 2.50 · Water: Tap water (in Table 2, the water content includes the cement dispersant)

[0051] (5) Preparation of hardened body The uncured mortar adjusted by the method described in (4) was filled into a cylindrical steel mold (height 10 cm, inner diameter 5 cm) coated with the aqueous release agent composition adjusted by the method described in (3) in 5 seconds, and cured by air curing at 20 °C for 15 hours and then demolded.

[0052] (6) Evaluation of release property The mortar hardened body prepared by the method described in (5) was demolded from a cylindrical steel mold (height 10 cm, inner diameter 5 cm), and visual observation of the surface of the hardened body after demolding and the surface of the steel mold was carried out to evaluate the release property based on the following criteria. The results are shown in Table 1. ○... It can be demolded without remaining peeling or color unevenness. △... Demolding causes some peeling residue and color unevenness. ×... Demolding causes peeling residue and color unevenness.

[0053]

Table 1

[0054]

Table 2

[0055] In Table 1, it can be seen that Examples 1 to 18 can achieve both one-component stability and mold release property as compared with Comparative Examples 1 to 12. This is considered to be because the aqueous mold release agent composition of the present invention contains a nonionic surfactant with a specific HLB value as component (A) in an appropriate ratio with an oily component as component (B), generating a microemulsion, suppressing the elution of the surfactant into the bulk of the hydraulic composition filled in the mold, and achieving both storage stability and mold release property.

Claims

1. An aqueous release agent composition containing (A) a nonionic surfactant having an HLB value calculated by the Griffin method of 5.0 or more and 13.0 or less (hereinafter referred to as component (A)) in an amount of 7% by mass or more and 90% by mass or less, (B) one or more mineral oils selected from kerosene, light oil, spindle oil, transformer oil, and machine oil (hereinafter referred to as component (B)), and (C) water (hereinafter referred to as component (C)), wherein the mass ratio (A) / (B) of the content of component (A) to the content of component (B) is 1 or more and 10 or less.

2. The aqueous release agent composition according to claim 1, wherein the mass ratio (B) / (C) of the content of component (B) to the content of component (C) is 0.01 or more and 5 or less.

3. The aqueous release agent composition according to claim 1 or 2, wherein component (A) is a nonionic surfactant represented by the following general formula (a1). R １ａ (CO) ｍ O-(AO) ｎ -R ２ａ (a1) [wherein, R １ａ is an aliphatic hydrocarbon group having 8 to 20 carbon atoms, and R ２ａ is a hydrogen atom or a methyl group. CO is a carbonyl group, and m is a number of 0 or 1. AO The group is an alkyleneoxy group having 2 to 4 carbon atoms containing an ethyleneoxy group. n is the average number of added moles and is a number from 1 to 15. ]]

4. The aqueous release agent composition according to any one of claims 1 to 3, containing component (A) in an amount of 7% by mass or more and 90% by mass or less, component (B) in an amount of 1% by mass or more and 50% by mass or less, and component (C) in an amount of 5% by mass or more and 90% by mass or less.

5. The aqueous release agent composition according to any one of claims 1 to 4, having an absorbance (Abs.) at a wavelength of 660 nm measured by an ultraviolet-visible spectrophotometer of 0 or more and 1.5 or less.

6. The aqueous release agent composition according to any one of claims 1 to 5, which is for a hydraulic composition.

7. A method for producing a hardened body of a hydraulic composition, comprising the following steps 1 to 4. Step 1: A step of kneading water and hydraulic powder to obtain a hydraulic composition. Step 2: A step of filling the mold coated or sprayed with the aqueous release agent composition according to any one of claims 1 to 6 with the hydraulic composition obtained in Step 1. Step 3: A step of curing the hydraulic composition filled in the mold obtained in Step 2. Step 4: A step of demolding the hardened body obtained in Step 3 from the mold.

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