JP6522996B6 - Antifouling agent and article coated with the coating film - Google Patents

Description

  The present invention relates to the improvement of the anti-adhesion properties of antifouling agents, particularly cement products such as mortar and concrete, which are problematic in construction sites and the like.

  Cement products such as mortar and concrete are manufactured by mixing cement and water and other necessary materials, and by hydration reaction between cement and water, fine particles are generated, and the whole hardens over time. Such cement products, if left inside the mixer or bucket, or scattered to wall materials, floor materials, etc., harden and adhere very firmly to the adhesion surface, so their removal is difficult. It is. In concrete construction, concrete is usually poured into the inside of a mold frame assembled using plywood, and after solidifying, the structure such as a base, an outer wall, and a pillar is formed by removing the mold frame, respectively. Even after removing the formwork, there is a possibility that concrete adhering to the casting surface may remain, and in such a case, not only the appearance and strength of the concrete structure are impaired but also the formwork after removal is next Although it is necessary to remove concrete deposits in order to use it, its removal is difficult due to the above-mentioned reasons. On the other hand, release agents for molds using surfactants, mineral oil, fats and oils, waxes, resins, etc. are known (see, for example, Patent Documents 1 and 2), but these are cements after curing It is intended to clean the product together with the release agent from the formwork, not to prevent adhesion of the cement product.

  On the other hand, the applicant has previously proposed a water repellent comprising a mixture containing silicone oil, fine particles of silica and the like, and a binder such as wax and paraffin (see Patent Document 3). However, this water repellent is inferior in the strength of the coating film, and when the viscous mud like cement products adheres to the coated surface, the water repellent itself peels off together, and thus the adhesion preventing property is maintained. I can not do it. Further, for example, there are known some water repellent materials which form a coating film composed of a mixture of silica fine particles and a silicone resin or a fluorocarbon resin and make it difficult to adhere stains (see, for example, Patent Documents 4 to 6). However, since silicone resins and fluorine resins having water repellency themselves are expensive, they may be used as paints for exterior walls of houses which are repainted in units of several years to several decades, for example, cement products There is a large economic burden on items that need to be maintained frequently, such as manufacturing machines and containers. In addition, although a water repellent or an antifouling material in which silica fine particles and an acrylic resin are mixed is also known (see, for example, Patent Documents 6 and 7), since it is a hydrophilic resin, There was a risk of accelerating the hardening of the cement product by the water present.

JP-A-5-293812 JP-A 5-305608 International Publication WO2005 / 063903 JP 2008-101197 A JP, 2011-246603, A Japanese Patent Application Publication No. 2003-147340 Unexamined-Japanese-Patent No. 2004-300345

  The problem to be solved by the present invention is to provide an antifouling agent which is excellent in preventing adhesion to cement products such as mortar and concrete and which can maintain its effect for a long time and which can be manufactured at relatively low cost. It is.

  In order to solve the above problems, the inventors of the present invention conducted intensive studies, and as a result, a specific type of resin was mixed with hydrophobic fine particles and an organic solvent, and this was applied to a surface to be antifouling target and dried. By forming a film, it has been found that it exhibits excellent adhesion preventing properties particularly to cement products such as mortar and concrete, and because it is excellent in alkali resistance and abrasion resistance, its effect can be maintained over a long period of time. The present invention has been completed.

  That is, the antifouling agent according to the present invention is characterized by containing (a) hydrophobic fine particles, (b) a modified polyolefin resin having a polar group and / or an epoxy resin, and (c) an organic solvent. It is. Moreover, in the said antifouling agent, it is preferable that content of (a) hydrophobic microparticles | fine-particles is 20-200 mass parts with respect to 100 mass parts of (b) resin. Moreover, in the said antifouling agent, it is preferable that the average particle diameter of (a) hydrophobic microparticles | fine-particles is 1-100 nm. In the antifouling agent, it is preferable that (a) the hydrophobic fine particles be hydrophobic silica. Moreover, in the said antifouling agent, it is preferable that (b) resin is chlorinated polyolefin resin. Moreover, in the said antifouling agent, it is preferable that (b) resin is an epoxy resin which can be hardened at normal temperature. Moreover, in the said antifouling agent, it is preferable that (b) resin is resin which does not produce a hydrolysis by pH 12.5.

  In the antifouling agent, it is preferable that (c) the organic solvent dissolves (b) the resin and (a) be capable of dispersing the hydrophobic fine particles. Moreover, in the said antifouling agent, it is preferable that the (c) organic solvent is less than 150 degreeC of boiling points. Moreover, in the said antifouling agent, it is preferable to use for the manufacturing machine of a cement product, a conveyance container, or a form. Moreover, it is preferable to use the said antifouling agent for a construction material, a construction machine, or a construction tool.

The article according to the present invention is characterized in that the coating with the antifouling agent is coated on the surface. In the article, the coating amount of the antifouling agent is preferably 5 to 1000 mg / dm ² . In the article, it is preferable that (a) the hydrophobic fine particles be fixed in a region of 85 to 99% of the projected area of the coating film-coated region with the surface of the fine particles exposed to the outside. Preferably, the article is a cement product manufacturing machine, a transport container or a mold. Preferably, the article is a construction material, a construction machine or a construction tool.

  The adhesion preventing method for a cement product according to the present invention is characterized in that the antifouling agent is applied to the surface of an article. In the above method, the antifouling agent is preferably applied to the surface of the cement product manufacturing machine, the transport container or the mold. In the above method, the antifouling agent is preferably applied to the surface of the construction material, construction machine or construction tool.

  The antifouling agent according to the present invention exhibits excellent adhesion preventing property to cement products such as mortar and concrete, and is excellent in alkali resistance and abrasion resistance, so that its effect can be maintained over a long period of time .

It is a SEM photograph figure of the coating-film surface which changed the hydrophobic silica content of the antifouling agent (hydrophobic silica + chlorinated polyolefin resin) of Experiment 4, and changed it variously. It is a figure which carried out black and white binarization of the SEM photograph of FIG. 1, and clarified shading. It is a SEM photograph of the coating-film surface which changed the hydrophobic silica content of the antifouling agent (hydrophobic silica + heat-hardening epoxy resin) of Experimental example 7, and changed it variously. FIG. 4 is a diagram in which the SEM photograph in FIG. 3 is binarized into black and white to clarify the shading.

  The antifouling agent according to the present invention is characterized by containing (a) hydrophobic fine particles, (b) a modified polyolefin resin having a polar group and / or an epoxy resin, and (c) an organic solvent.

<(A) hydrophobic fine particles>
The hydrophobic fine particles (a) used in the antifouling agent of the present invention may be either an inorganic substance or an organic substance, but those made of an inorganic substance which does not deteriorate are preferable. In order to obtain fine particles with a particle size on the order of nm, inorganic oxides such as silica, alumina and titania are preferable, and in particular, silica is the most preferable. The average particle diameter of the hydrophobic fine particles is preferably 1 to 100 nm, and more preferably 5 to 20 nm. As a commercial product of fine particle silica, for example, hydrophobic silica such as Aerosil R972, 972V, R972CF, R974, R812, R805, R805, RX200, RX300, RY200 (all manufactured by Nippon Aerosil Co., Ltd.) can be suitably used, and Among them, R972, RX200 and RY200 are particularly preferable. Other commercially available fine particles include Aerosil 50, 90 G, 130, 200, 200 V, 200 CF, 200 FAD, 300, 300 CF, 380, R 202, R 812 S, OX 50, TT 600, MOX 80, MOX 170, COK 84, aluminum oxide C, titanium dioxide T 805. And titanium dioxide P25 (all of which are manufactured by Nippon Aerosil Co., Ltd.) etc., among these fine particles, those having a hydrophilic surface are previously used with higher fatty acids, silicone oils, silane coupling agents, etc. It is necessary to make it hydrophobic.

  The amount of the (a) hydrophobic fine particles added to the antifouling agent is not particularly limited, but is preferably 20 to 200 parts by mass with respect to 100 parts by mass of the (b) resin, and further preferably 40 to 100 It is desirable that it is a mass part (Hereinafter, the said mass unit may be described as PHR [Per-Hundred-Resin]). If the amount of the hydrophobic fine particles added is too large, the abrasion resistance of the coated film after drying may be reduced and it may be easily peeled off. On the other hand, the amount of the hydrophobic fine particles added is If the amount is small, antifouling properties may not be exhibited. In addition, by adjusting the amount of the (a) hydrophobic fine particles to be in the above range, the (a) hydrophobic fine particles protrude from the (b) resin matrix of the coating film surface substantially hemispherically and are discharged to the outside. It is believed that this can exhibit excellent antifouling properties. The total amount of (a) hydrophobic fine particles and (b) resin is preferably 5 to 50% by mass in the total amount of the antifouling agent. The total amount of (a) and (b) can usually be easily adjusted by changing (c) the amount of the organic solvent added.

<(B) Resin>
In the antifouling agent of the present invention, a modified polyolefin resin and / or an epoxy resin having a polar group is used as the resin (b). The modified polyolefin resin that can be used in the present invention is a polymer obtained by polymerizing an unsaturated hydrocarbon (olefin) having 2 to 10 carbon atoms into which a polar group such as an acid functional group or a halogen atom is introduced. For example, polyethylene, polypropylene, polybutene, polypentene, polyhexene, polyheptene, polyoctene, polynonene, polydecene, or a mixture thereof can be used as the main skeleton polymer. The molecular weight is not particularly limited, but is usually about 10,000 to 1,000,000. In addition, since a polyolefin resin is nonpolar, it is difficult to dissolve in a solvent as it is, and adhesion to other materials is poor. On the other hand, the above-mentioned drawbacks can be improved by partially modifying the hydrogen atoms in the polyolefin structure with halogen atoms such as chlorine or acid-containing compounds such as maleic acid. In the present invention, particularly chlorinated polyolefin resins can be suitably used. The chlorination ratio of the chlorinated polyolefin resin is preferably in the range of 10 to 54% by mass, particularly 20 to 35% by mass, based on the total amount of the resin. Furthermore, an acid-modified chlorinated polyolefin resin modified with an acid such as acrylic acid may be used. As a commercial item of chlorinated polyolefin resin, for example, Hard Ren 14-LWP, CY-9124P, P-5528 (all are Toyobo Co., Ltd. make), Super Clon L-206, 813 A, 822, 930, 224 H, 240 H (all are Nippon Paper Industries Co., Ltd.) and the like.

  In addition, the epoxy resin that can be used in the present invention includes a main agent composed of a compound having an epoxy group (glycidyl group) at an end, and a curing agent capable of reacting with the epoxy group to form a crosslinked structure. The main agent of the epoxy resin is not particularly limited. For example, in addition to bisphenol type epoxy resins such as bisphenol A type and bisphenol F type, phenol novolac type epoxy resin, cresol novolac type epoxy resin, brominated type epoxy resin A resin, a heterocyclic epoxy resin, an alicyclic epoxy resin, a biphenyl type epoxy resin, a naphthalene type epoxy resin, a glycidyl ester type epoxy resin etc. are mentioned, You may mix and use these plurality. Among these, bisphenol A epoxy resins can be suitably used. The molecular weight is not particularly limited, but is usually about 10,000 to 1,000,000. Moreover, the epoxy equivalent of an epoxy resin is although it does not specifically limit, Usually, it is about 100-3000 g / eq, and 200-1000 g / eq is especially preferable. It is necessary to adjust the blending amount of the curing agent in accordance with the epoxy equivalent of the main agent.

  Also, the type of curing agent used for the epoxy resin is not particularly limited, but, for example, aliphatic polyamine, epoxy resin adduct of aliphatic polyamine, ketone reactant of aliphatic polyamine (ketoimine), polyaminoamide (amide Resin), polymercaptan etc. are mentioned. Besides these, aromatic polyamines and acid anhydrides are also known as curing agents for epoxy resins, but these curing agents usually require heating at 100 ° C. or higher for curing reaction, for example After applying the antifouling agent to a cement product manufacturing machine, a transport container, or a construction material or construction machine, it is practically difficult to heat and dry the coating film under an environment of 100 ° C. or higher. On the other hand, curing agents such as aliphatic polyamines exemplified above are all generally capable of curing under an environment of about normal temperature (25 ° C.) to about 80 ° C. In the resin (b) used in the present invention, it is desirable that the combination of the main agent and the curing agent be appropriately adjusted so that curing can be performed at normal temperature (25 ° C.). As a curing agent at normal temperature, amine adducts or polyamidoamines can be particularly preferably used. The mixing ratio of the main agent and the curing agent may be adjusted according to the epoxy equivalent of the resin of the main agent and the amine equivalent of the curing agent or the active hydrogen equivalent, and the ratio of each equivalent is about 1: 2 to 2: 1 Or it is desirable to adjust so that it may become in the range of 1: 1.5-1.5: 1.

  The main component of the epoxy resin and the curing agent may be a one-component formulation mixed in advance or a two-component formulation mixed at the time of use. However, in a normal case, the one-component epoxy resin needs to be heated to a relatively high temperature of, for example, 100 ° C. or more to advance the curing reaction so that the curing reaction does not proceed at normal temperature. On the other hand, in the case of a two-component epoxy resin, the curing reaction can proceed at normal temperature or a relatively low temperature after mixing. For this reason, a two-component, room temperature curing epoxy resin may be desirable from the viewpoint of usability as an antifouling agent. When the antifouling agent of the present invention is used as a two-component system, for example, a liquid agent containing only a curing agent and a liquid agent containing other components are separately prepared, and the inside of a suitable container is prepared immediately before application as an antifouling agent. You can mix each at. In addition, if necessary, curing reaction accelerators such as tertiary amines, imidazoles, phosphonium salts, sulfonium salts and the like may be added. Commercially available epoxy resins include, for example, 1001B80, 1001X70, 1001T75 (all manufactured by Mitsubishi Chemical Corporation), 57-K313M (manufactured by Kansai Paint Co., Ltd.), etc., as one-component thermosetting preparations. As two-component cold-setting preparations, for example, Esdyne # 3100, # 3200 (all manufactured by Sekisui Chemical Co., Ltd.), F-05C, F-30C (all manufactured by Arteco), Epomarin GX, JW (both Also manufactured by Kansai Paint Co., Ltd.).

  In addition, since cement produces calcium hydroxide by contacting with water, cement products containing water such as mortar and concrete usually exhibit basicity of about pH 12.5. For this reason, for example, the polyester resin causes hydrolysis of an ester bond by contact with a cement product to deteriorate the resin. In addition, for example, in an epoxy resin using an acid anhydride as a curing agent, since a crosslinked structure is formed by an ester bond, as in the case of a polyester resin, there is a possibility that hydrolysis may occur by contact with a cement product. On the other hand, for example, an epoxy resin cured with an olefin resin or an amine is excellent in so-called alkali resistance because it is not easily decomposed even under basic conditions. The resin (b) used in the present invention is preferably a resin which does not cause hydrolysis at pH 12.5.

  Although the addition amount of (b) resin in the antifouling agent is not particularly limited, the content of (a) hydrophobic fine particles is 20 to 200 parts by mass, particularly 50 parts by mass with respect to 100 parts by mass of (b) resin. It is desirable to adjust the addition amount of (b) resin so that it becomes 100 mass parts. When the amount of the resin (b) added is large, the relative amount of the (a) hydrophobic fine particles may be reduced, and the antifouling property may not be exhibited. In addition, when the amount of the resin (b) added is small, the amount of the (a) hydrophobic fine particles relatively increases and the abrasion resistance of the coating film is lowered. In addition, the total amount of (a) hydrophobic fine particles and (b) resin is preferably 5 to 50% by mass in the total amount of the antifouling agent.

<(C) Organic solvent>
The organic solvent used in the antifouling agent of the present invention is a known organic solvent conventionally used for general paints, which can dissolve (b) a resin and can disperse (a) hydrophobic fine particles. As long as it is, you may use any thing. The organic solvent evaporates to form a coating film in which (a) hydrophobic fine particles are dispersed in (b) resin. Examples of organic solvents that can be used in the present invention include aromatic hydrocarbon solvents such as toluene and xylene, petroleum naphtha, mineral spirits, aliphatic hydrocarbon solvents such as n-hexane, isohexane and cyclohexane, acetone, methyl ethyl ketone Ketone solvents such as methyl isobutyl ketone and diisobutyl ketone, ester solvents such as ethyl acetate and butyl acetate, ether solvents such as methyl cellosolve, butyl cellosolve and butyl carbitol, alcohols such as methanol, ethanol, isopropyl alcohol and butanol A solvent is mentioned and you may use these individually or in mixture of multiple. Among these, in particular, an organic solvent having a boiling point of less than 150 ° C. can be suitably used. In addition, as an antifouling agent of this invention, it is desirable for a formulation not to contain water at all. When water is contained in the antifouling agent, a small amount of water remains in the dried coating, which may accelerate hardening due to a hydration reaction with a cement product attached to the coating.

  The amount of the (c) organic solvent added to the antifouling agent is not particularly limited, and may vary depending on the type and amount of (a) hydrophobic fine particles and (b) resin, but 50 to 95% of the total amount of the antifouling agent It is desirable to set it as mass%. (C) If the amount of the organic solvent is too large, it may take time to form a coating by evaporation and drying, and the viscosity of the preparation may be lowered to cause dripping from the coated surface. On the other hand, when the amount of (c) organic solvent is small, the viscosity of the antifouling agent becomes too high, and it becomes difficult to uniformly disperse or dissolve (a) hydrophobic fine particles or (b) resin in the preparation Usability becomes worse as uniform application to the surface becomes difficult.

  In addition to the essential components (a) to (c) described above, the antifouling agent of the present invention may, for example, be a pigment, a pigment dispersant, a plasticizer, a thickener, An appropriate amount of various components such as a foaming agent, a coalescent agent, an antiseptic agent, an antifungal agent, an antibacterial agent, an ultraviolet absorber and the like may optionally be contained.

  The antifouling agent of the present invention can be produced by stirring and mixing each essential component of the above (a) to (c) and, if necessary, the above various optional components. For the stirring and mixing of the respective components, for example, conventionally known mixers such as a ball mill, a sand mill, a homogenizer, a propeller mixer, a paint shaker and the like may be used. Usually, (b) resin is stirred and dissolved in (c) organic solvent, and then (a) hydrophobic fine particles and other optional components are added and stirred and mixed, (a) hydrophobic fine particles and the like are uniformly dispersed. Is easy to obtain. Alternatively, a commercially available resin for paint may be used in which (b) resin is dissolved in (c) organic solvent in advance. In addition, when using a two-component epoxy resin as the resin (b), a solution of a curing agent and a preparation in which components other than the curing agent are stirred and mixed are separately manufactured, and these two agents are mixed at the time of use To use.

  The target article to which the antifouling agent of the present invention is applied is not particularly limited. However, since the antifouling agent of the present invention can exhibit excellent adhesion preventing property particularly to cement products such as mortar and concrete, for example, a cement raw material crusher, a classifier, and a fresh concrete car (track mixer) ), Machines for manufacturing cement products such as concrete mixers, transport containers such as buckets and trays, plywood forms for mortar or concrete construction, and construction of wall materials and floorings used in construction sites handling cement products Particularly effective use of the antifouling agent of the present invention on the surface of articles related to cement products such as construction machines such as dump trucks, cranes, and pile drivers, construction tools such as hammers and drivers, etc. it can.

  The method for applying the antifouling agent of the present invention to the surface of the article is not particularly limited. For example, spray coating, roll coating, flow coating, spin coating, dip coating, electrostatic coating, brushing, sponge coating, etc. According to the conditions such as the shape and size of the target article, an appropriate coating method may be appropriately selected and performed.

The coating amount of the antifouling agent of the present invention on the surface of the article (adhesion amount per unit area after coating film drying or baking) is not particularly limited, but adjusted to the range of 5 to 1000 mg / dm ² Preferably 10 to 100 mg / dm ² . If the application amount of the antifouling agent is smaller than the above range, the adhesion preventing effect of the cement product may not be obtained. On the other hand, even if the application amount is larger than the above range, the antifouling effect is further improved It is not desirable from the economical point of view because it can not be seen, it may be worse appearance by coating thick.

  Further, on the surface of the article after forming a coating film by the antifouling agent of the present invention, (a) hydrophobic fine particles in an area of 85 to 99%, more preferably 90 to 95% of the projected area of the coating film covering area It is desirable to fix the fine particle surface in the exposed state to the outside. This can be adjusted by the content ratio of (a) hydrophobic fine particles to (b) resin in the antifouling agent, and when the content ratio of (b) resin is too high, most of the hydrophobic fine particles are Since it exists in the inside of a coating film and sufficient surface asperity is not formed in the coating film surface, antifouling property may not be able to be exhibited. On the other hand, (a) when the hydrophobic fine particles are excessively exposed from the coating film surface, the fine particles are easily peeled off by light abrasion, so that the antifouling property can not be maintained.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to the contents of these examples.

Test Example 1 (Hydrophobic Silica Dispersion)
Five grams of hydrophobized silica fine particles (Aerosil RY200: manufactured by Nippon Aerosil Co., Ltd.) having an average particle diameter of 12 nm was added to 95 g of ethanol and mixed with stirring to obtain Test Example 1.

Test Example 2 (Hydrophobic Silica + Silicone Oil)>
5 g of hydrophobized silica fine particles (Aerosil RY200: manufactured by Nippon Aerosil Co., Ltd.) having an average particle diameter of 12 nm, 0.25 g of polydimethylsiloxane (SH-100: manufactured by Toray Dow Corning Co., Ltd.), titanium tetra-2-ethylhexoxide ( 0.25 g of organics TA-30 (manufactured by Matsumoto Fine Chemical Co., Ltd.) was added to 94.5 g of ethanol and mixed with stirring to obtain Test Example 2.

Test Example 3 (Hydrophobic Silica + Polyester Resin)>
5.5 g of hydrophobized silica fine particles (Aerosil RY200: manufactured by Nippon Aerosil Co., Ltd.) having an average particle diameter of 12 nm and 12.5 g of a saturated polyester resin (UE3600: manufactured by Unitika; molecular weight 20,000) in a 1: 1 mixed solvent of toluene / methyl ethyl ketone The mixture was added to 80 g and stirred and mixed to obtain Test Example 3 (effective concentration of hydrophobic silica: 60 PHR).

Test Example 4 (Hydrophobic Silica + Chlorinated Polyolefin Resin)>
5.5 g of hydrophobized silica fine particles (Aerosil RY200: manufactured by Nippon Aerosil Co., Ltd.) having an average particle diameter of 12 nm and 12.5 g of a chlorinated polyolefin resin (Super Clon L-206: manufactured by Nippon Paper Industries; a chlorination rate of 32% by mass) The mixture was added to 80 g of a 1: 1 mixed solvent of methyl ethyl ketone and stirred and mixed to obtain Test Example 4 (effective concentration of hydrophobic silica: 60 PHR).

Test Example 5 (Hydrophobic Silica + Two-Liquid Room-Temperature Curing Epoxy Resin)>
Main component of epoxy resin solution (Epomarin GX: Kansai Paint Co., Ltd .; two-component epoxy resin, solvent: xylene, toluene, etc.) Hydrophobicized silica fine particles (Aerosil RY200: Nippon Aerosil) having an average particle diameter of about 11 g and an average particle size of 12 nm And 6 g) were mixed with stirring. About 1 g of a curing agent for the same epoxy resin (Epomarine GX: manufactured by Kansai Paint Co .; amine adduct) was added to and mixed with this mixture to obtain Test Example 5 (effective concentration of hydrophobic silica: 50 PHR).

Test Example 6 (Hydrophobic Silica + Two-Liquid Room-Temperature Curing Epoxy Resin)>
Hydrophobicized silica fine particles (Aerosil RY200: Nippon Aerosil) with a main ingredient of epoxy resin solution (Epomarine JW: Kansai Paint Co., Ltd .; two-component epoxy resin, solvent: xylene, toluene, etc.) and about 11 g of resin actual content and 12 nm average particle diameter Made by stirring and mixed. About 1 g of a curing agent for the same epoxy resin (Epomarine JW: manufactured by Kansai Paint Co .; polyamide amine) was added to and mixed with this mixture to obtain Test Example 6 (effective concentration of hydrophobic silica: 50 PHR).

<Test Example 7 (Hydrophobic silica + one-component heat curing epoxy resin)>
Epoxy resin solution (57-K313M: Kansai Paint Co., Ltd .; one-component epoxyurea resin, curing agent: urea resin, solvent: petroleum naphtha, xylene, ethylbenzene, etc.) 12 g of hydrophobic silica particles (Aerosil RY 200) with an average particle diameter of 12 nm : 6 g of manufactured by Nippon Aerosil Co., Ltd. was stirred and mixed to obtain Test Example 7 (effective concentration of hydrophobic silica: 50 PHR).

Water Repellant Effect and Durability of Antifouling Agent Coating First, a coating is formed by the antifouling agent composition of each of the above-mentioned test examples, and water is evaluated to evaluate the antifouling effect (water repellency) of the coating film surface. The contact angle and the water fall angle were measured. Further, in the state where the coating film surface was worn, the water contact angle and the water falling angle were similarly measured, and the abrasion resistance of the antifouling coating film according to each test example was evaluated.
Evaluation criteria are as follows. The results are shown in Table 1.

[Water contact angle, water fall angle]
The antifouling composition of each of the test examples was applied onto the surface of an aluminum substrate at a coating amount of 10 mg / dm ² to prepare a test piece. A water droplet of 10 μL was dropped on the coating film surface of each test piece, and the water contact angle and the water fall angle were measured using a contact angle meter CA-DT (manufactured by Kyowa Interface Science Co., Ltd.).

[Abrasion resistance]
Attach a 1 cm x 1 cm gauze to a flat indenter on the coating film surface of each test piece coated with various antifouling agents in the same manner as in the test above, using a Tribogear surface measuring machine TYPE: 38 (manufactured by Shinto Scientific Co., Ltd.) A reciprocation test was performed a predetermined number of times with a load of 10 g. The water contact angle and the water fall angle are measured using a contact angle meter CA-DT (manufactured by Kyowa Interface Science Co., Ltd.) for each test piece for each single reciprocation, and the water contact angle 150 ° or more and the water fall angle 90 ° or less The number of round trips that can be held was examined.

  As shown in Table 1 above, in Test Examples 1 and 2 which do not contain a resin as a film forming agent, although excellent water repellent effects (water contact angle and water fall angle) are shown, only one reciprocation in the abrasion tester The water repellency was lost, and it turned out that there is almost no abrasion resistance. On the other hand, in Test Examples 3 to 7 prepared by adding an appropriate amount of resin, the abrasion resistance is improved as compared with Test Examples 1 and 2 not including this, and in particular, tests using an epoxy resin. In Examples 5 to 7, antifouling agents having very excellent abrasion resistance were obtained.

The effect of the antifouling agent coating on adhesion to cement products Next, in order to examine the antifouling effect of the coating of each test example on cement products, how much water is repelled when the coating is immersed in an alkaline solution for a predetermined time We examined whether the effect could be maintained. Moreover, it evaluated about the slipperiness (cement repellence) at the time of making a cement product adhere to the coating film surface by two types of methods.
Evaluation criteria are as follows. The results are shown in Table 1.

[Alkali resistance]
Each test piece coated with various antifouling agents in the same manner as the above test is immersed in a pH 12.5 aqueous NaOH solution for 1 minute, 3 minutes, 6 minutes, 10 minutes, and then separately exposed to water and withdrawn. The immersion time which can maintain the state where a water droplet does not remain on top was investigated.

[Cement repellence (static test)]
After placing 20 g of cement paste (a mixture of cement and an appropriate amount of water) on the coating film surface of each test piece coated with various antifouling agents in the same manner as the above test and leaving it for 1 minute, The cement paste was slid down to an angle of °°. This test was repeated, and was continued until more than 50% cement paste of the contact surface remained attached to the test piece, and the number of tests that could be slipped off was examined.
[Cement repellence (drop test)]
20 g of cement paste was dropped from a height of 10 cm from the test piece while each test piece coated with various antifouling agents was inclined 45 ° in the vertical direction in the same manner as the above test, and the surface of the test piece was slid down. This test was repeated and continued until the cement paste stuck to the surface of the test piece and did not slip off, and the number of tests that could be slipped off was examined.

  As shown in Table 2 above, the antifouling agent of Test Example 3 using a polyester resin has low alkali resistance, and it has a water repellent effect by immersing it in a pH 12.5 solution comparable to that of general concrete for 1 minute. It has been lost. On the other hand, all of the antifouling agents of Test Examples 4 to 7 using a chlorinated polyolefin resin or a normal temperature or heat curing epoxy resin were excellent in alkali resistance. Moreover, also in the cement repellence test evaluated using an actual cement product, good results were obtained with the antifouling agents of the same test examples 4 to 7 using a chlorinated polyolefin resin or an epoxy resin.

The hydrophobic silica content in the antifouling agent The present inventors have investigated the antifouling agent in which the content ratio of the hydrophobic silica to the resin was variously changed in order to examine the appropriate content of the hydrophobic fine particles in the antifouling agent. The agents were adjusted to examine the antifouling effect (water contact angle and sliding angle) of the coating film surface. In addition, the antifouling agent composition changes the hydrophobic silica addition amount with respect to each resin according to the said test example 4 (hydrophobic silica + chlorinated polyolefin resin) and the test example 7 (hydrophobic silica + heat-hardening epoxy resin) Various antifouling agents were prepared, and the water contact angle and the water fall angle were measured in the same manner as the above-mentioned test on the surface of the coated film.
The results are shown in Table 3 below. Further, FIGS. 1 and 3 show SEM photographs of the coating film surface of each test example having different hydrophobic silica contents, and FIGS. 2 and 4 show those obtained by making the SEM photographs black and white and clarifying the light and shade.

  As shown in Table 3 above, the content of the hydrophobic silica necessary to show a sufficient antifouling effect is 60 PHR or more in Test Example 4 in which a chlorinated polyolefin is used, and Test Example 7 in which a heat curing epoxy resin is used. The result was different from 30 PHR or more depending on the type of resin. In addition, although not shown in the above table, when the hydrophobic silica content exceeds 200 PHR in any of the resins, the hydrophobic silica on the surface of the coating tends to come off and the abrasion resistance tends to deteriorate. It was

  In addition, it can be confirmed from FIGS. 1 and 3 that as the content of the hydrophobic silica increases, the proportion of the fine particles exposed onto the surface of the coating increases. Moreover, according to FIGS. 2 and 4 in which FIGS. 1 and 3 are binarized into black and white, the white part is considered to be the surface of the hydrophobic silica fine particle exposed to the outside. The ratio of the hydrophobic silica fine particles exposed on the coating film surface can be roughly confirmed based on the ratio of the area of the white area to Here, considering the ratio of the white area of each of the photographs corresponding to the hydrophobic silica 60 PHR of Test Example 4 which starts to exert a sufficient antifouling effect and the hydrophobic silica 30 PHR of Test Example 7 from Table 3 above, the surface is considered When the proportion of the hydrophobic silica exposed to the upper side is about 85% or more, it is considered that a sufficient antifouling effect starts to be exhibited on the coating film surface.

The coated amount of the antifouling agent on the surface of the article Also, in order to examine the effective coated amount of the antifouling agent of the present invention, per unit area using the antifouling agent composition of the above test example Test pieces were prepared by variously changing the coating amount (adhesion amount per unit area after coating film drying or baking), and the antifouling effect (water contact angle and sliding angle) of each coating film surface was examined. In addition, the antifouling agent composition conforms to the test example 4 (hydrophobic silica + chlorinated polyolefin resin) and the test example 7 (hydrophobic silica + heat-curing epoxy resin), and the coating film surface is water in the same manner as the above test. The contact angle and the water fall angle were measured.
The results are shown in Table 4 below.

As shown in Table 4 above, in the antifouling agents of Test Examples 4 and 7 containing hydrophobic silica fine particles and a chlorinated polyolefin or heat-cured epoxy resin, each of the antifouling agents has a coating amount of 5 to 1000 mg / dm ² , It was confirmed to show a sufficient antifouling effect. From the point of the antifouling effect, it is desirable to set the application amount to 10 mg / dm ² or more. On the other hand, even if it is applied more than 100 mg / dm ^2, most of the antifouling effect is improved according to the application amount From the economic point of view, it is desirable to set it to 100 mg / dm ² or less because it can not be seen.

Claims (14)

(A) hydrophobic silica fine particles having an average particle size of 1 to 100 nm ,
(B) Chlorinated polyolefin resin and / or epoxy resin curable at room temperature ;
(C) organic solvent,
Including
Content of the said hydrophobic silica is 20-200 mass parts with respect to 100 mass parts of said (b) resin, The adhesion inhibitor of the unhardened cement product characterized by the above-mentioned . The anti-adhesion agent for an uncured cement product according to claim 1, wherein the resin (b) is a resin which does not cause hydrolysis at pH 12.5. The adhesion prevention of the unhardened cement product according to any one of claims 1 and 2 , characterized in that the (c) organic solvent dissolves the (b) resin and (a) the hydrophobic fine particles can be dispersed. Agent. The anti-adhesion agent for an uncured cement product according to any one of claims 1 to 3 , wherein the (c) organic solvent has a boiling point of less than 150 ° C. The anti-adhesion agent for an uncured cement product according to any one of claims 1 to 4 , which is used in a machine for producing a cement product, a transport container or a form. The anti-adhesion agent for an uncured cement product according to any one of claims 1 to 5 , which is used for a construction material, a construction machine or a construction tool. An article having a surface coated with a coating of the uncured cement product according to any one of claims 1 to 6 , which is coated with the anti-adhesion agent. The article of claim 7 in which the coating amount of adhesion inhibitor of the uncured cement product characterized in that it is a 5 to 1000 mg / dm ^2. 9. The hydrophobic fine particles according to claim 7, wherein the hydrophobic fine particles are fixed in a region of 85 to 99% of the projected area of the coating film coated area with the fine particle surface exposed to the outside. Goods. The article according to any one of claims 7 to 9 , which is a machine for producing cement products, a transport container or a mold. The article according to any one of claims 7 to 10 , which is a construction material, a construction machine or a construction tool. A method for preventing adhesion of a cement product, comprising applying the anti-adhesion agent for an uncured cement product according to any one of claims 1 to 6 on the surface of an article. The method for preventing adhesion of cement products according to claim 12 , wherein the anti-adhesion agent for the uncured cement products is applied to the surface of a machine for producing cement products, a transport container or a mold. The method for preventing adhesion of cement products according to claim 13 , wherein the anti-adhesion agent for the uncured cement products is applied to the surface of a construction material, a construction machine or a construction tool.