JP2022184556A - Aqueous release agent composition - Google Patents

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 The present invention relates to an aqueous release agent composition and a method for producing a cured product of a hydraulic composition using the same.

Many industrial products typified by concrete, ceramics, plastics, resins, and foodstuffs are produced by filling uncured curable compositions into molds and curing them by drying or chemical reaction in the post-process to obtain cured products. Manufactured by
Therefore, in order to ship the above industrial products, a process called "demolding" is required to remove the hardened body from the formwork. A process chemical called "release agent" or "release agent" (hereinafter collectively referred to as "release agent") is used.
In order to reduce the adhesive force between the mold and the curable composition, the release agent generally contains an oil with low surface tension or a surfactant that lowers the surface tension. They are roughly divided into oil-based release agents containing activators and the like, and water-based release agents containing water.

As a water-based 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 hydrocarbon oil, water, and a surfactant. ing.
Moreover, in Patent Document 2, a mixed fat is obtained by combining a fat that is solid or semi-solid at room temperature as a base oil and has an elevated melting point (according to the standard fat analysis test method) of 20 to 60 ° C. and a fat that is liquid at room temperature. Or 12 to 40% by weight of mineral oil, 1.0 to 7% by weight of a nonionic surfactant obtained by mixing nonionic surfactants with different HLB values as an emulsifier and adjusting the HLB to 6.0 to 14.0, emulsifying aid 0.3 to 6% by weight of a cationic surfactant as an agent and an oil film strengthening agent, 0.2 to 6% by weight of a cyclic amine ethoxylate as a water-displacement type rust inhibitor, and the remainder being water, making the total 100% by weight. , discloses an O/W emulsion type release agent composition for concrete, which is obtained by subjecting this composition to a dispersion treatment using a homogenizer to obtain fine particles of 0.1 to 10 μm.
Further, in Patent Document 3, an oil group dispersible in water by a surfactant is added at a ratio of 2 to 10 wt% relative to the total amount, and a water-soluble polymer is added at a rate of 0.01 to 10 wt% relative to the total amount. %, and diluted with water.

Japanese Patent Application Laid-Open No. 53-125423 JP-A-11-19915 JP-A-11-151711

Since general release agents are applied to the mold by spraying or coating, from the viewpoint of sprayability and workability, they are low-viscosity oily components, that is, relatively low carbon numbers, and are flammable. High oil is often used.
In addition, many water-based release agents have poor product stability (single-part stability) in a water-blending system, so water is blended immediately before use and adjusted and used as an emulsion, so it is highly flammable. It will be stored in the form and subject to storage restrictions.

The present invention provides an aqueous release agent composition that achieves both storage stability and releasability, and a method for producing a cured product of a hydraulic composition using the same.

The present invention provides (A) a nonionic surfactant having an HLB value of 5.0 or more and 13.0 or less calculated by the Griffin method (hereinafter referred to as component (A)) in an amount of 7 mass% or more and 90 mass% or less. , (B) an oil 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 the content of component (A) and It relates to an aqueous mold release agent composition in which the mass ratio (A)/(B) to the content of component (B) is 1 or more and 10 or less.

The present invention also relates to a method for producing a hardened body of a hydraulic composition, comprising steps 1 to 4 below.
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 formwork obtained in step 2.
Step 4: A step of demolding the cured body obtained in Step 3 from the formwork.

INDUSTRIAL APPLICABILITY According to the present invention, an aqueous release agent composition that achieves both storage stability and releasability, and a method for producing a cured product of a hydraulic composition using the same are provided.
In recent years, SDGs "Sustainable Development Goals" have been advocated 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 improve the productivity of the curable composition and improve the storage stability, thereby realizing reduction of waste. For example, SDGs No. 7, 8, 9, 11, 12 and so on.

The present inventors have found that the nonionic surfactant having a specific HLB value, which is the component (A), and the oily component, which is the component (B), are contained in a specific ratio to improve storage stability and separation. It was found that an aqueous release agent composition having excellent moldability can be obtained.
Although the mechanism by which the aqueous release agent composition of the present invention exhibits excellent storage stability and releasability is not necessarily clear, it is speculated as follows.
When a surfactant is contained in an aqueous release agent composition containing an oily component and water, the surfactant improves the stability of the emulsion by lowering the oil-water interfacial tension. It is presumed that the surfactant is also eluted into the bulk of the hydraulic composition, lowering the surface tension and, as a result, increasing the affinity between the mold and the hydraulic composition, thereby promoting sticking to the mold. be.
However, in the aqueous release agent composition of the present invention, a one-liquid transparent aqueous release agent can be obtained by containing a nonionic surfactant having a specific HLB value in an appropriate ratio with an oily component. , it is considered that a microemulsion with a smaller micelle diameter than the emulsion is produced. In the microemulsion system, the micelle surface area becomes much larger than in the normal emulsion system, and most of the surfactants are presumed to exist at the oil-water interface. It is considered that this suppresses the elution of the surfactant into the bulk of the hydraulic composition filled in the mold, thus achieving both storage stability and releasability.

[Aqueous release agent composition]
<(A) Component>
The aqueous 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 polyoxyalkylene group portion of component (A))/(molecular weight of component (A))] x 20 (1)
The molecular weight of the polyoxyalkylene group portion of the component (A) is calculated using the value of the average number of added moles of the polyoxyalkylene group.
For nonionic surfactants whose HLB cannot be determined by the Griffin method, HLB determined by experiments shall be adopted. For the experimental method, the method described in "Handbook of Surfactants" published by Sangyo Tosho Co., Ltd., edited by Ichiro Nishi et al., 5th edition, January 10, 1966, page 319, is employed.

The HLB of component (A) is 5.0 or higher, preferably 6.0 or higher, more preferably 7.0 or higher, still more preferably 8.0 or higher, and even more preferably 8.5, from the viewpoint of releasability. From the above and from the viewpoint of releasability, it is 13.0 or less, preferably 12.0 or less, more preferably 11.0 or less, and still more preferably 10.5 or less.

From the viewpoint of storage stability, component (A) is preferably a nonionic surfactant represented by the following general formula (a1).
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, and R ^2a is a hydrogen atom or a methyl group. CO is a carbonyl group and m is the number 0 or 1. The AO group is an alkyleneoxy group having 2 or more and 4 or less carbon atoms including an ethyleneoxy group. n is the average number of added moles and is a number of 1 or more and 15 or less. ]

In general formula (a1), R ^1a is preferably 10 or more, more preferably 12 or more, still more preferably 14 or more from the viewpoint of storage stability, and preferably It is an aliphatic hydrocarbon group of 18 or less, more preferably 16 or less, preferably an alkyl group or an alkenyl group.
In general formula (a1), m is a number of 0 or 1, preferably 1.
In the general formula (a1), the AO group is an alkyleneoxy group containing an ethyleneoxy group and having 2 to 4 carbon atoms, preferably an alkyleneoxy group containing an ethyleneoxy group and having 2 to 3 carbon atoms, and more An ethyleneoxy group is preferred. The AO groups may be alkyleneoxy groups, including ethyleneoxy groups and other alkyleneoxy groups, such as propyleneoxy groups. Another 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 a block type bond or a random type bond. Ethyleneoxy groups give higher HLB values than propyleneoxy groups.
In general formula (a1), n is the average number of added moles, and from the viewpoint of storage stability, it is preferably 3 or more, more preferably 4 or more, and still more preferably 5 or more, and from the viewpoint of storage stability, The number is preferably 13 or less, more preferably 11 or less, and even more preferably 9 or less.

<(B) Component>
The aqueous release agent composition of the present invention contains an oily component as component (B).
Component (B) includes (1) mineral oils such as kerosene, light oil, spin oil, transformer oil, and machine oil, (2) synthetic oils such as polyalkylene glycol, and (3) rapeseed, palm, palm, and soybean oils. (4) oils and fats, (5) fatty acid esters, and the like.
Component (B) is preferably mineral oil, more preferably one or more mineral oils selected from kerosene, light oil, spin oil, transformer oil, and machine oil, and still more preferably, from the viewpoint of releasability. is one or more mineral oils selected from spin oils and machine oils.

(B) A commercial thing can be used for a component.
When a spin oil is used as the component (B), examples of the spin oil include Cosmo Pure Spin E and Cosmo Pure Spin ESP (both manufactured by Cosmo Oil Lubricants Co., Ltd.), with Cosmo Pure Spin ESP being preferred.
When machine oil is used as the component (B), the machine oil can be Cosmo Pure Safety 10, Cosmo Pure Safety 22, Cosmo Pure Safety 32, Cosmo Pure Safety 46, or Cosmo Pure Safety 68 (all of which are Cosmo Oil). manufactured by Lubricants Co., Ltd.).

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

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

From the viewpoint of releasability, the aqueous release agent composition of the present invention preferably contains component (B) in an amount of 1% by mass or more, more preferably 5% by mass or more, and still more preferably 10% by mass or more, and From the viewpoint of moldability, the content is 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.

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

The aqueous release agent composition of the present invention contains the component (C) in an amount of 10% by mass or more, preferably 20% by mass or more, more preferably 30% by mass or more, and still more preferably 40% by mass, from the viewpoint of aesthetic appearance of the surface of the cured product. 90% by mass or less, preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less from the viewpoint of releasability.

In the aqueous release agent composition of the present invention, the mass ratio (B)/(C) between the content of component (B) and the content of component (C) is preferably 0.00 from the viewpoint of releasability. 01 or more, more preferably 0.05 or more, more preferably 0.1 or more, still more preferably 0.3 or more, and from the viewpoint of aesthetic appearance of the cured body surface, preferably 5 or less, more preferably 4 or less, It is more preferably 3 or less, even more preferably 2 or less, and even more preferably 1 or less.

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

The aqueous release agent composition of the present invention may contain a nonionic surfactant other than the component (A), but the 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] between the content of component (A) and the content of all nonionic surfactants is the effect of the present invention. From the viewpoint of not impairing the can be

In the aqueous release agent composition of the present invention, the absorbance (Abs.) at a wavelength of 660 nm by an ultraviolet-visible spectrophotometer is 0 or more, preferably 1.5 or less, more preferably 1.5 or less, from the viewpoint of storage stability. is 0.5 or less, more preferably 0.2 or less, even more preferably 0.1 or less, still more preferably 0.08 or less, and even more preferably 0.05 or less.
Absorbance (Abs.) is measured at a constant wavelength of 660 nm using a UV-visible spectrophotometer (eg, UV-160A manufactured by Shimadzu Corporation) using distilled water as a blank.
The aqueous release agent composition of the present invention contains a microemulsion having a micelle diameter smaller than that of an emulsion. there is Here, since the emulsion scatters light, the larger the emulsion diameter and the higher the emulsion concentration, the higher the absorbance. Therefore, it can be said that the smaller the absorbance, the better the one-liquid stability (phase stability), because the larger the emulsion diameter and the higher the emulsion concentration, the more likely coalescence and layer separation occur.

The aqueous release agent composition of the present invention contains, as other components, an antifoaming agent, an antioxidant, a preservative, a metal sealing agent, and a solvent (excluding components (A) and (B)). You may

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 mop. These release agents can also be used as lubricants.
The amount of the aqueous release agent composition of the present invention to be applied or sprayed onto the mold is preferably 0.5 g/m ² or more, more preferably 1 g/m ^{2 or} more, from the viewpoint of releasability and surface appearance. More preferably 1.5 g/m ² or more, preferably 40 g/m ² or less, more preferably 38 g/m ² or less, and even more preferably 36 g/m ² or less.

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

A hydraulic composition contains a hydraulic powder, and the hydraulic powder is a powder having a physical property of hardening by a hydration reaction, and examples thereof include cement and gypsum.
Examples of cement include ordinary Portland cement, high-early-strength Portland cement, ultra-high-early-strength Portland cement, sulfate-resistant Portland cement, low-heat Portland cement, white Portland cement, and ecocement (for example, JIS R5214, etc.). Among these, cement selected from ordinary Portland cement, sulfuric acid-resistant Portland cement and white Portland cement is preferred, and ordinary Portland cement is more preferred.

Hydraulic powder such as cement may also include powder having pozzolanic action and/or latent hydraulic properties such as blast furnace slag, fly ash and silica fume, stone powder (calcium carbonate powder) and the like. For example, blast furnace slag cement, fly ash cement, silica fume cement, etc. may be used.

From the viewpoint of productivity and strength, the hydraulic composition is usually Abbreviated as W/P. ] is preferably 10% or more, more preferably 15% or more, still more preferably 20% or more, still more preferably 30% or more, and preferably 60% or less, more preferably 55% or less, further preferably 50% % or less can be used.

The hydraulic composition may further contain aggregate. Aggregates include fine aggregates, coarse aggregates, and the like. Fine aggregates are preferably mountain sand, land sand, river sand, and crushed sand, and coarse aggregates are preferably mountain gravel, land gravel, river gravel, and crushed stone. Depending on the application, lightweight aggregate may be used. The term "aggregate" is based on "Concrete Overview" (June 10, 1998, published by Gijutsu Shoin).

Aggregates can be used in the usual range used for preparing concrete, mortar, and the like. When the hydraulic composition is concrete, the amount of coarse aggregate used is preferably 50% or more in bulk volume, more preferably 55% or more, still more preferably 60% or more, and 100%, from the viewpoint of concrete properties. The following is preferable, 90% or less is more preferable, and 80% or less is even more preferable. In addition, 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, more preferably 700 kg/m ³ or more, from the viewpoint of improving filling properties in a formwork or the like. /m ³ or more is more preferable, 1000 kg/m ³ or less is preferable, and 900 kg/m ³ or less is more preferable. 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 2000 kg/m ³ or less. is preferred, 1800 kg/m ³ or less is more preferred, and 1700 kg/m ³ or less is even more preferred.

The hydraulic composition can also contain other components in addition to the above components. Examples thereof include dispersants, antifoaming agents, AE agents, retarders, foaming agents, thickeners, foaming agents, waterproofing agents, fluidizing agents, early strengthening agents and the like. As an early strengthening agent, a compound selected from hydrochlorides, sulfates, nitrates, nitrites, cyanates, thiocyanates, thiosulfates and formates of alkali metals and alkaline earth metals, or alkanolamines and glycerin derivatives , formaldehyde derivatives, catechol derivatives, and nanoparticles of hydrated products of Portland cement (C—S—H and calcium hydroxide).

[Method for producing aqueous release agent composition]
The method for producing an aqueous release agent composition of the present invention is a method for producing the aqueous release agent composition. That is, in the present invention, the component (A), the component (B), and the component (C) are mixed at a mass ratio (A)/(B ) are mixed at 1 or more and 10 or less.
The method for producing the aqueous release agent composition of the present invention can appropriately apply the items described for the aqueous release agent composition of the present invention.
Components (A), (B), (C) and other components are the same as those described for the aqueous release agent composition of the present invention.
In the method for producing the aqueous release agent composition of the present invention, the mixing amount and mass ratio of each component are the content and mass ratio of each component described in the aqueous release agent composition of the present invention. It can be applied to the mixed amount from .

[Method for producing hardened body of hydraulic composition]
The method for producing a cured product of a hydraulic composition of the present invention is a method for producing a cured product 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 formwork obtained in step 2.
Step 4: A step of demolding the cured body obtained in Step 3 from the formwork.
To the method for producing the hardened body of the hydraulic composition of the present invention, the items described for the aqueous release agent composition and the method for producing the same of the present invention can be appropriately applied.

In step 1, the aspects described for the hydraulic composition can be applied as appropriate. In step 1, the content of each component in the hydraulic composition described above can be read as the mixing amount.

In step 2, the aqueous release agent composition of the present invention may be applied to the mold by spraying, instead of using a brush or mop. These release agents can also be used as lubricants.
The amount of coating or spraying of the aqueous release agent composition of the present invention onto the mold is preferably 0.5 g/m ² or more, more preferably 1 g/m ² or more, from the viewpoint of releasability and surface appearance. , 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, and even more preferably 36 g/m ² or less.
Examples of the method of filling the hydraulic composition into the mold include a method of directly charging the hydraulic composition from a mixer, a method of pumping the hydraulic composition with a pump and introducing it into the mold, and the like.

In step 3, the hydraulic composition filled in the mold obtained in step 2 is cured.
In step 3, for example, the time during which the hydraulic composition is maintained at a curing temperature of 50° C. or higher as the curing condition is preferably 1 hour or longer, preferably 24 hours or shorter, and more preferably 20 hours or shorter. When the hydraulic composition filled in the formwork is cured while being held at 50° C. or higher, it can be cured by autoclave curing, steam curing, or the like.
In step 3, the hydraulic composition may be cured without steam curing. In the case of manufacturing mortar or concrete products without steam curing, the time from contacting cement with water to demolding in the preparation of a hydraulic composition is 4 hours or more and 48 hours from the viewpoint of productivity and strength. The following are preferred. In this case, the temperature is preferably 0° C. or higher, more preferably 5° C. or higher, and 45° C. or lower, more preferably 40° C. or lower. Heating and/or cooling within this temperature range can be carried out as appropriate.

In step 4, the cured body obtained in step 3 is removed from the mold. Steps 3 and 4 can be performed continuously under a series of temperature controls. Demolding of the cured body can be carried out according 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 contacting water with cement to the start of demolding, from the viewpoint of productivity and strength, 4 hours or more, more preferably 5 hours or more, and 48 hours or less, more preferably 40 hours or less.

The hardened hydraulic composition obtained by the method for producing a hardened hydraulic composition of the present invention can be used for high-fluidity concrete, water-inseparable concrete, lightweight high-fluidity concrete, water-permeable concrete, and cast-in-place linings. Suitable for construction method (ECL construction method) and SENS construction method.

(A) component, (B) component, and (C) component used the following.

<(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

<(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, Rheodor SP-O10V, manufactured by Kao Corporation, HLB value: 4.3

<(B) Component>
・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

(1) Preparation method of aqueous release agent composition Each of the above components is added to a 50 mL vial bottle so that the content shown in Table 1 is obtained, and mixed vigorously by inversion at 20°C to prepare each aqueous release agent composition. did.

(2) Method for evaluating one-pack stability Each aqueous release agent composition prepared by the method described in (1) was stored at 20°C for 1 week, then filled in 3 mL of a disposable cell and measured by ultraviolet-visible light spectrophotometry. Absorbance (Abs.) at a constant wavelength of λ=660 nm was measured with a UV-160A meter (manufactured by Shimadzu Corporation) using distilled water as a blank, and used as an index of one-liquid stability. Here, since the emulsion scatters light, the larger the emulsion diameter and the higher the emulsion concentration, the higher the absorbance. The larger the emulsion diameter and the higher the emulsion concentration, the more likely coalescence and layer separation occur. Therefore, it can be said that the smaller the absorbance, the better the one-liquid stability (phase stability). When layer separation occurred during storage, the solution was stirred vigorously in advance, degassed by sonication, and then measured for absorbance. Table 1 shows the results.

(3) Formwork preparation Each aqueous release agent composition prepared by the method described in (1) was applied to a cylindrical steel formwork (height 10 cm, inner diameter 5 cm) using a brush.

(4) Preparation of Uncured Curable Composition A mortar was prepared according to the composition 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 the mixture at 62 rpm for 120 seconds using a mortar mixer specified in JIS R5201. As a cement dispersant, Mighty 21VS (manufactured by Kao Corporation) is used, and the amount of cement dispersant added is a flow cone (upper diameter 70 mm x lower diameter 100 mm x height 60 mm) described in JIS R 5201. Then, the mortar flow was adjusted to 250±10 mm.

The ingredients used to prepare the mortar are as follows.
・ Cement: 1:1 (mass ratio) mixture of ordinary Portland cement manufactured by Taiheiyo Cement Co., Ltd. and ordinary Portland cement manufactured by Sumitomo Osaka Cement Co., Ltd., specific gravity 3.16
・Sand: Surface dry specific gravity 2.50 from Joyo, Kyoto Prefecture
・ Water: tap water (in Table 2, water content includes cement dispersant)

(5) Preparation of hardened body Uncured mortar prepared by the method described in (4) is coated with an aqueous release agent composition prepared by the method described in (3) A cylindrical steel mold (height 10 cm) , inner diameter of 5 cm) was filled for 5 seconds, cured in air at 20°C for 15 hours, and removed from the mold.

(6) Evaluation of releasability 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). Visual observation of the surface of the formwork was carried out to evaluate releasability based on the following criteria. Table 1 shows the results.
○: The mold can be demolded without any residue or color unevenness.

In Table 1, it can be seen that Examples 1 to 18, compared to Comparative Examples 1 to 12, can achieve both one-pack stability and releasability. This is because the aqueous release agent composition of the present invention contains a nonionic surfactant having a specific HLB value as component (A) and an oily component as component (B) in an appropriate ratio. It is considered that a microemulsion was generated, the elution of the surfactant into the bulk of the hydraulic composition filled in the mold was suppressed, and both storage stability and releasability were achieved.

Claims (8)

(A) 7% by mass or more and 90% by mass or less of 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)); It contains an oily component (hereinafter referred to as component (B)) and (C) water (hereinafter referred to as component (C)), and the mass ratio of the content of component (A) to the content of component (B) ( An aqueous release agent composition wherein A)/(B) is 1 or more and 10 or less. 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, wherein component (A) is a nonionic surfactant represented by the following general formula (a1).
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, and R ^2a is a hydrogen atom or a methyl group. CO is a carbonyl group and m is the number 0 or 1. The AO group is an alkyleneoxy group having 2 or more and 4 or less carbon atoms including an ethyleneoxy group. n is the average number of added moles and is a number of 1 or more and 15 or less. ] The aqueous release agent composition according to any one of claims 1 to 3, wherein component (B) is one or more mineral oils selected from kerosene, light oil, spin oil, transformer oil, and machine oil. . Claims 1 to 3, containing 7 mass% to 90 mass% of component (A), 1 mass% to 50 mass% of component (B), and 5 mass% to 90 mass% of component (C). The aqueous release agent composition according to any one of claims 1 to 3. 6. The aqueous release agent composition according to any one of claims 1 to 5, which has an absorbance (Abs.) of 0 or more and 1.5 or less at a wavelength of 660 nm measured by an ultraviolet-visible spectrophotometer. 7. The aqueous release agent composition according to any one of claims 1 to 6, which is used for hydraulic compositions. A method for producing 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 according to any one of claims 1 to 7.
Step 3: A step of curing the hydraulic composition filled in the formwork obtained in step 2.
Step 4: A step of demolding the cured body obtained in Step 3 from the formwork.