JP2023010488A - Super water-repellent coating agent for forming water bead, method for producing super water-repellent coating agent, and toy using the super water-repellent coating agent - Google Patents

Abstract

To provide a super water-repellent coating agent that can easily create a super water-repellent coating that forms water bead and is friendly to the environment and the human body, and to provide a toy in which the super water-repellent coating is used.SOLUTION: A super water-repellent coating agent that forms a super water-repellent coating on the surface of a different substrate is a non-fluorine-based super water-repellent coating agent comprising a chain-shaped hydrophilic silica nanoparticle (A), an alcoholic solvent (B), water (C), a first silane (D), a second silane (E), a silane hydrolysis catalyst (F) and an adhesive (G). A water bead toy using the super water-repellent coating agent comprises at least an application tool (T2), a drip tool (T3), and a coloring solution (T4) using the super water-repellent coating agent (T1).SELECTED DRAWING: Figure 1

Description

The present invention relates to a super water-repellent coating agent for forming polka dots, a method for producing the super water-repellent coating agent, and a toy using the super water-repellent agent.

Soap bubbles are widely used as children's toys. As a teaching material for scientific knowledge, it is often used as a science experiment in schools and TV programs. The soap bubble liquid composition used to generate soap bubbles is distributed as a single item or as a toy in combination with a tool such as a straw. You can easily enjoy soap bubbles. It is thought that soap bubbles became popular as a toy because a scientific phenomenon that is generally unfamiliar attracts people's attention with fun and curiosity. So far, in order to use soap bubbles as toys, various things such as soap bubble generating tools and soap bubble liquids used for generating soap bubbles have been developed and invented.

However, there are almost no inventions relating to toys using polka dots.
In Patent Document 1, there is a hull that floats on the surface of the water, and by maintaining the liquid surface at a constant position while the floating hull is submerged, a constant amount of water is constantly applied to the water drop generation mechanism. water can be supplied, the toy is capable of continuously ejecting water droplets upward from the inside of the toy.

Patent Document 2 discloses a water drop generator having an inlet, a motor for driving the water drop generator, a power source for operating the motor, a liquid tank having an outlet for holding liquid, and the liquid tank. A running toy is described in which a guide passage for guiding the liquid inside to the polka dot generator and wheels are provided in the toy body.

In Patent Document 3, a transfer path for transferring water droplets is formed by a hydrophobic member whose surface is flocked, and a toy that can be played by transferring the water droplets formed by a drip such as a dropper along this transfer path. is described.

In Patent Document 4, a water-repellent layer is provided on the surface of a support in which a frame portion having a height is formed substantially around the entire periphery, and a water-repellent layer that makes a placed liquid into a polka-dot state is provided. / Or a game toy is described in which a discoloration part is provided on a support at a position parallel to the water-repellent layer, the discoloration part being discolored when water droplets come into contact with the support.

In the natural world, it is well known that polka dots on lotus leaves are rolling. The secret behind the formation of the polka dots is that the surface of the lotus leaf has a nano-micrometer scale hydrophobic uneven structure, which strongly repels water. This is called the Lotus effect. In particular, if the contact angle of water is 150° or more and the sliding angle is 10° or less, the surface is said to be superhydrophobic.

To fabricate a superhydrophobic surface, a technology that combines the use of materials with low surface energy and the design of nano- and micro-scale double-surface relief structures is required. As materials with low surface energy, two types of water-repellent materials, fluorine-based resins and silicone-based resins, are mainly used. Inorganic nanoparticles such as silica, titanium oxide, zinc oxide, and calcium carbonate are commonly used to create nano/microscale double-surface textured structures. In the method of making a super water-repellent surface, a suspension solution obtained by dissolving a resin water-repellent material in a solvent and dispersing inorganic nanoparticles is spray-coated on the surface of a base material, followed by drying or heat treatment. Forming an aqueous surface is the lowest cost and simplest method.

Patent Document 5 describes at least i) texturing a surface by depositing nanoparticles of different sizes, ii) cross-linking the textured surface with a cross-linking agent, and iii) perfluorinated hydrophobic A method for producing transparent, superhydrophobic coatings is described in a three-step process that includes modifying the properties of the surface with organic organic polymers.

Non-Patent Document 1 reports a method of dispersing silica nanoparticles hydrophobized by silane coupling treatment in an ethanol solvent to obtain a suspension, and forming a superhydrophobic coating on a glass substrate by a spray coating method. ing.

Non-Patent Document 2 discloses chain hydrophilic silica nanoparticles dispersed in ethanol by hydrolysis of two silanes, tetraethoxysilane (TEOS) and triethoxy-1H,1H,2H,2H-heptadecafluorodecylsilane (HDFTES). A method of modifying the surface of particles, preparing an amphipathic suspension solution, and forming a superhydrophobic coating on various target surfaces such as glass, metal, and resin by a one-step spray coating method has been reported.

In Non-Patent Document 3, silica nanoparticles hydrophobized with 3-aminopropyltriethoxysilane (APTES) are dispersed in absolute ethanol, and dodecyltrimethoxysilane (DDTMS) is used as a surface modifier for silica nanoparticles, epoxy A one-step dip coating method is reported to form a durable superhydrophobic coating on substrates such as glass and stainless steel by preparing a paint-like suspension using a resin as an adhesive together with a polyamide curing agent. It is

Japanese Utility Model Laid-Open No. 54-75896

JP 2006-102349 A

Japanese Utility Model Laid-Open No. 59-64195

Japanese Unexamined Patent Application Publication No. 2017-209132

JP 2017-522172 A

Hitoshi Ogiwara, J.; Vac. Soc. Jpn. 58, (2015), 431

GeD. T. et al. , Part. Part. Syst. Character. 31, (2014), 763

Zhang Z. H. et al. , Scientific Reports, 8, (2018), 3869

In the above-mentioned conventional polka-dot toys, the generation of polka-dots is limited to the structure of the toy itself, so that children cannot make polka-dots as they like, unlike soap bubbles. Furthermore, when playing with polka dots due to superhydrophobicity, it is not possible to easily create a superhydrophobic surface like a lotus leaf.

According to Patent Document 5, a super water-repellent coating that forms polka dots can be produced, but the production conditions are complicated and severe, so it is not applicable to how toys are played. According to Non-Patent Document 1, a superhydrophobic surface can be easily produced, but there is a problem that target materials are limited or durability is insufficient.

According to Non-Patent Document 2, a super water-repellent coating that forms polka dots on various target surfaces such as glass, metal, and resin can be easily produced. or insufficient durability. Fluorine-based resins are most commonly used as water-repellent materials because they can repel not only aqueous solutions such as water, coffee, and milk, but also organic solvents such as oil, alcohol, and gasoline. However, fluorine-based water repellents contain PFOA (perfluorooctanthane) as an impurity, which is difficult to decompose. Therefore, in recent years, countries around the world have tightened regulations on fluorine-based water repellents. In December 2020, Japan also designated PFOA-related substances as Class 1 Specified Chemical Substances under the Chemical Substances Control Law, prohibiting their use and import.

According to Non-Patent Document 3, a superhydrophobic coating that forms polka dots can be produced, but the coating is not transparent and cannot be reused as a tool.

Many superhydrophobic materials have been developed so far, but because the uneven structure of the surface is very fine, the superhydrophobic surface easily breaks down due to external mechanical force and loses its superhydrophobicity. Therefore, for many superhydrophobic materials, durability is a major issue for practical use. In addition, many super water-repellent coating agents contain petroleum-based solvents that are harmful and have a pungent odor, which poses safety problems for the environment and the human body.

In view of such circumstances, the present invention is based on a completely new idea, and based on a completely new idea, it is possible to easily create a super water-repellent coating on the surface of a tool as a different material, and play by freely moving water droplets. To provide a coating agent and its epoch-making polka dot toys.

The present inventors aimed to invent a super water-repellent coating agent that can easily create a super water-repellent surface that forms polka dots that children can enjoy. Using chain-like hydrophilic silica nanoparticles, disperse them in a solvent that is a mixture of ethanol and water, which is highly safe for the environment and the human body, and use at least two fluorine-free silane agents to make the surfaces of the silica nanoparticles hydrophobic. An amphipathic super-hydrophobic suspension solution that can be applied to various substrates was prepared by modifying the Furthermore, the present invention has been completed by discovering a polymer adhesive that can improve the durability in order to maintain the superhydrophobicity of the coating.

The present invention provides a super water-repellent coating agent that forms water droplets rolling on the surface of different substrates to form a super water-repellent coating, comprising at least one silica nanoparticle (A), an alcoholic solvent (B), Provide a super water-repellent coating agent containing water (C), a first silane (D), a second silane (E), a silane hydrolysis catalyst (F), and an adhesive (G) do.

The shape of the silica nanoparticles (A) may be spherical, but preferably chain-like with a minor axis of 5 nm to 30 nm and a major axis of 20 nm to 200 nm. Among the particle sizes of the chain silica nanoparticles, it is more preferable that the short axis is 10 nm to 15 nm and the long axis is 40 nm to 100 nm. The chain silica nanoparticles are preferably hydrophilic. The raw material form of the silica nanoparticles is not particularly limited. It may be powder or colloidal silica. When colloidal silica is used as a raw material, the mass concentration of silica nanoparticles is preferably 15 wt % or more. The amount of colloidal silica added is preferably 0.30 to 15.00 wt%, more preferably 0.50 to 10.00 wt%, relative to the blended mass of the superhydrophobic coating agent. That is, the amount of silica nanoparticles added is preferably 0.10 to 5.00 wt%, more preferably 0.10 to 1.50 wt%, relative to the blended mass of the superhydrophobic coating agent.

As the alcohol solvent (B), any one of methanol, ethanol, isopropyl alcohol (IPA), isobutyl alcohol, normal butyl alcohol, benzyl alcohol, etc. may be used alone, or two or more of them may be used in combination. Although it may be used, ethanol is preferred. The purity of ethanol as a solvent is not particularly limited, but it is preferably 85% or more. For example, mixed ethanol with a purity of 85 wt % or higher can be used. The amount of alcohol solvent to be added is preferably 60 to 90 wt%, more preferably 75 to 85 wt%, relative to the blended mass of the superhydrophobic coating agent.

The water (C) is preferably purified water. For example, both ion-exchanged water and distilled water may be used. The amount of water added is preferably 1 to 30 wt%, more preferably 5 to 20 wt%, relative to the blended mass of the superhydrophobic coating agent.

The volume ratio of the alcohol solvent (B) and water (C) is preferably alcohol:water = 5.0 to 10.0, more preferably alcohol:water = 6.0 to 8.0. preferable.

The first silane (D) is preferably tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS), and the amount added is 0.05 to 3.0% relative to the blended mass of the superhydrophobic coating agent. 00 wt%, more preferably 0.15 to 1.00 wt%.

The second silane (E) is preferably a silane compound represented by the following general formula (E-1). For example, hexyltrimethoxysilane (n=5) (HTMS), dodecyltrimethoxysilane (n=11) (DDTMS), hexadecyltrimethoxysilane (n=15) (HDTMS), octadecyltrimethoxysilane (n=17 ) (ODTMS), hexyltriethoxysilane (n=5) (HTES), dodecyltriethoxysilane (n=11) (DDTES), hexadecyltriethoxysilane (n=15) (HDTES), octadecyltriethoxysilane ( n=17) (ODTES) and the like. The amount of the second silane (E) added is preferably 0.01 to 1.50 wt%, more preferably 0.05 to 1.00 wt%, relative to the blended mass of the superhydrophobic coating agent.

［式（Ｅ－１）中、Ｒはメチル基又はアミン基、メタクリル基又はエポキシ基、オレフィン基を表し、Ｒ１はメチル基又はエチル基又はクロロ基を表し、ｎは２価の炭化水素基の数を表し、ｎ＝５以上であることが好ましい。］

[In the formula (E-1), R represents a methyl group or an amine group, a methacrylic group or an epoxy group, or an olefin group, R represents a methyl group, an ethyl group or a chloro group, and n represents a divalent hydrocarbon group. It is preferable that n=5 or more. ]

The mass ratio of the amount of the first silane (D) and the second silane (E) added is preferably first silane:second silane=1.0 to 6.0, preferably 2.0 to 4.0. It is more preferable to have

When using tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS) as the first silane (D) for the use of the first silane (D) and the second silane (E), R1 is a methyl group. A silane compound is preferably used as the second silane (E).

The silane hydrolysis catalyst (F) is preferably an alkaline substance. Examples thereof include ammonia water, tetramethylammonium hydroxide (TMAH) aqueous solution, sodium hydroxide, etc. Among them, ammonia water is more preferable. The concentration of ammonia water is not particularly limited, but the mass concentration is preferably 28% to 30%, and the amount added is 0.1 to 10.0 wt% relative to the blended mass of the super water-repellent coating agent. is preferred, and 0.5 to 5.0 wt% is more preferred.

The adhesive (G) is preferably at least one selected from water-soluble polyacrylic acid (PAA), polyvinyl alcohol (PVA), and polyvinylpyrrolidone (PVP). Among them, it is preferable that any molecular weight is 10,000 or more, and it is more preferable that any molecular weight is 20,000 or more. Alternatively, it is preferable to use polyvinyl butyral (PVB), which is insoluble in water but soluble in ethanol. The molecular weight of polyvinyl butyral is preferably 10,000 or more, more preferably 20,000 or more. Either one of the water-soluble adhesive and the water-insoluble adhesive may be used alone, or one water-soluble adhesive and the water-insoluble adhesive PVB may be used in combination.

Regarding the method of using the adhesive (G), it is preferable to prepare an aqueous solution of the water-soluble adhesive in advance using, for example, polyacrylic V acid (PAA). The mass concentration of the aqueous solution of the water-soluble adhesive is preferably 2 wt % or more, more preferably 5 wt % or more. For water-insoluble adhesives, it is preferable to prepare a solvent solution (eg, ethanol) of the water-insoluble adhesive in advance, for example, with polyvinyl butyral (PVB). The mass concentration of the water-insoluble adhesive solvent solution is preferably 5 wt % or more, more preferably 10 wt % or more.

The amount of the adhesive (G) added is preferably 1.0 to 300.0 wt%, more preferably 5.0 to 50.0 wt%, relative to the amount of the silica nanoparticles in the superhydrophobic coating agent. is more preferred.

Further, in the present invention, there is provided a super water-repellent coating agent manufacturing method for manufacturing the super water-repellent coating agent described above, wherein silica nanoparticles (A) are added and dispersed while stirring the alcoholic solvent (B). The dispersion comprising the second step, comprising a first step, and a second step of adding and dissolving the first silane (D) and the second silane (E) while stirring the dispersion comprising the first step. a third step of adding water (C), adhesive (G) and catalyst (F) while stirring.

In the present invention, the order of adding raw materials in each step of the production method is not particularly limited, but in the second step of the production method, the order is first silane (D) → second silane (E). is preferred. In the third step of the manufacturing method, it is preferable that the order is water (C)→adhesive (G)→catalyst (F).

In the present invention, the stirring method or stirring device is not particularly limited in the three steps of the manufacturing method. A stirrer called a magnetic stirrer may be used, in which a stirrer coated with Teflon or the like containing a magnet is rotated from the outside of the container to transmit power by a magnetic field. A stirrer called a mechanical stirrer that stirs via a stirrer may be used.

In the present invention, the stirring method or stirring device is not particularly limited in the three steps of the production method, but stirring speed conditions are required. When using a magnetic stirrer, in order to produce 80 g of the super water-repellent coating agent using a 200 ml triangular beaker as a container, it is preferable that the stirrer has a size of Φ8×30 mm and the stirring speed is 400 rpm or more, and 800 rpm or more. It is more preferable to have When using a mechanical stirrer or a mechanical stirrer, in order to produce 1000 g of the super water-repellent coating agent using a 2000 mL plastic bottle (Φ126 x 254 mm) as a container, a movable two-blade stirrer with a blade width of 100 mm during rotation is required. , the stirring speed is preferably 400 rpm or more.

In the present invention, in the first step of the production method, the stirring time after adding the silica nanoparticles is preferably 5 minutes or longer, more preferably 10 minutes or longer. In the second step of the production method, the stirring time after adding the first silane (D) and the second silane (E) is preferably 5 minutes or longer, more preferably 10 minutes or longer. In the third step of the production method, the stirring time is preferably 12 hours or longer, more preferably 24 hours or longer.

In the present invention, temperature conditions in all steps of the production method are not particularly limited. It may be room temperature, or may be heated up to 60°C.

Moreover, in the present invention, the order of steps in the manufacturing method is not limited to the order of first step→second step→third step. For example, the super water-repellent coating of the present invention can be produced in the order of the first step→the third step→the second step. When the superhydrophobic coating of the present invention is produced in the order of the first step → third step → second step, in the step of adding the first silane (D) and the second silane (E), the first silane (D ) and the second silane (E) are preferably added at slow rates. For example, when the production amount of the super water-repellent coating agent is 1000 kg, the addition rates of the first silane (D) and the second silane (E) are 2.5 L/h and 0.9 L/h or less, respectively. and more preferably 1.5 L/h and 0.5 L/h or less, respectively.

In the super water-repellent coating agent composition of the present invention, when aqueous ammonia is used as the silane hydrolysis catalyst (F), the super water-repellent coating agent obtained in the above third step has an ammonia odor to be removed. A deodorizing step called the fourth step can be added. Although the deodorization method is not particularly limited, it is preferably a bubbling method called an ammonia stripping method in which a carrier gas is used to vaporize the liquid in the liquid material container. Although the operating temperature in the deodorizing step by the bubbling method is not particularly limited, it is preferably 30° C. or higher, more preferably 50° C. or higher.

The superhydrophobic coating agent of the present invention is characterized in that although precipitation or phase separation occurs during storage, it can be sufficiently redispersed simply by shaking it manually.

The method of producing a super water-repellent coating using the super water-repellent coating agent of the present invention is characterized by a very simple one-step spray application, which does not require high-temperature drying or heating, and can be used by natural drying.

Although the method of applying the superhydrophobic coating agent of the present invention is not particularly limited, spray application is preferred. A spray application method may be a spray bottle, a spray can (aerosol type), or a spray gun.

The superhydrophobic coating agent of the present invention is characterized by having amphipathic properties, and superhydrophobic on the surfaces of glass, ceramics, porcelain tiles, baked tiles, metals, wood, plastics, paper, cloth, etc. of any shape. A coating can be formed.

Moreover, the conditions for drying the super water-repellent coating with the super water-repellent coating agent of the present invention are not particularly limited. It may be natural drying, a dryer, or a drying apparatus. In the case of natural drying, the drying time is preferably 4 hours or longer, more preferably 8 hours or longer, and most preferably 24 hours or longer.

Moreover, the super water-repellent coating formed by using the super water-repellent coating agent of the present invention is characterized by having transparency and durability.

In addition, the super water-repellent coating formed by using the super water-repellent coating agent of the present invention is characterized by being able to be reapplied as it is on a portion as needed.

In addition, the super water-repellent coating formed using the super water-repellent coating agent of the present invention can be easily removed with a daily detergent or a solution containing alcohol, if necessary, to form a super water-repellent coating again. That is, the superhydrophobic coating agent of the present invention is characterized in that the target substrate can be used repeatedly.

The super water-repellent coating agent of the present invention does not contain a fluorine component, does not contain a petroleum solvent that is harmful to health and has an irritating odor, and is characterized by being able to easily form a super water-repellent coating on the surface of various substrates. To provide a toy that can be played with polka dots and a method of playing with polka dots.

In the present invention, a toy using a super water-repellent coating agent includes at least a super water-repellent coating agent (T1), an application tool (T2), a drip tool (T3), and a coloring solution (T4). It is not limited to these.

In the toy using the super water-repellent coating agent of the present invention, the material and shape of the coating tool (T2) are not particularly limited. The shape of (T2) of the applicator may be a simple surface, a spherical shape, or a doll shape (when experiencing the repelling of polka dots against clothes). ), which may be in the form of a complex maze.

In the toy using the superhydrophobic coating agent of the present invention, the infusion tool (T3) is not particularly limited. Any dripping method may be used as long as the solution is dripped intermittently to form droplets on the superhydrophobic coating applied to the coating tool (T2). Specific examples include a dropper, a syringe, an infusion bottle, and the like.

In the toy using the super water-repellent coating agent of the present invention, the coloring solution (T4) contains yellow, magenta, and cyan coloring materials. It is preferably a colorant of three primary colors, and more preferably three kinds of coloring solutions representing the three primary colors of the colorant.

According to the present invention, chain-shaped hydrophilic silica nanoparticles are used instead of spherical ones, dispersed in a solvent such as a mixture of ethanol and water, which is highly safe for the environment and the human body, and containing at least two fluorine-free silane agents. is used to hydrophobically modify the surface of silica nanoparticles, and a polymer adhesive is used to manufacture a super water-repellent coating agent with amphipathic properties that can be applied to various substrates, and the super water-repellent coating agent. A polka dot toy using the method and its superhydrophobic coating can be provided.

The superhydrophobic coating agent of the present invention 1) completely repels water droplets, 2) is friendly to the environment and the human body, 3) has durability, 4) can be applied to a wide range of substrates, and 5) can be applied to various surfaces. and 6) high practicality.

According to the super water-repellent coating agent of the present invention and the polka dot toy using the super water-repellent coating agent, children can easily make a lotus leaf-like surface on which polka dots roll on the surface of different materials or different shapes. You can experience a sense of accomplishment by reproducing the lotus effect with your own hands while enjoying the rolling polka dots.

In addition, according to the super water-repellent coating agent of the present invention and the polka dot toy using the super water-repellent coating agent, it has the same fun and scientific wonder as soap bubbles, so it can be used as an educational toy as the child grows. , it can be expected to be useful in enhancing curiosity about science. In addition, it can be expected to be applied as a scientific experiment in schools and the like.

In addition, the super water-repellent coating agent of the present invention can be expected to be used in everyday life as well as in industrial fields as a method for solving stains, freezing, corrosion, and growth of bacteria and viruses caused by water droplets. can. For example, outdoor wear, umbrellas, clothing such as casual wear, houses (kitchens, baths, toilets, etc.), construction, automobiles, railroads, ships, aircraft, overhead high-voltage power lines, communication towers, antennas, parabolic antennas (for satellite communications) , solar panels, wind turbines, etc.

1 is a cross-sectional view schematically showing the structure of a super water-repellent coating formed using the super water-repellent coating agent of the present invention; FIG. 1 is a flowchart showing an example of a method for producing a super water-repellent coating agent of the present invention; FIG. 1 is a photograph of the appearance of a sample showing an example of the super water-repellent coating agent of the present invention. 1 is a photograph of the appearance of a super water-repellent coating obtained by a spray coating method on a glass surface using the super water-repellent coating agent of the present invention and the repelled polka dots. 1 is a photograph of the appearance of a super water-repellent coating obtained by a spray coating method on a tile surface using the super water-repellent coating agent of the present invention, and the repelled polka dots. 1 is a photograph of the appearance of a super water-repellent coating obtained by a spray coating method on a wood surface using the super water-repellent coating agent of the present invention and repelled polka dots. 1 is a photograph of the appearance of a super water-repellent coating obtained by a spray coating method on a corrugated cardboard surface using the super water-repellent coating agent of the present invention and the repelled polka dots. The results of an adhesion test of a super water-repellent coating on a slide glass surface obtained by a spray coating method using the super water-repellent coating agent of the present invention: (b) Appearance of the paint film after peeling off the adhesive tape and photograph of repelled polka dots Using the super water-repellent coating agent of the present invention, the water resistance test results of the super water-repellent coating on the slide glass surface obtained by the spray coating method: (c) immersion in hot water at 40 ° C. for 68 hours, (d) 90 Appearance of coating film after immersion in hot water at ℃ for 3 minutes 1 is a photograph of the appearance of an example of a polka dot toy using the super water-repellent coating agent of the present invention: (T1) super water-repellent spray coating agent, (T2) application route tool, (T3) drip dropper, (T4) Three colored solutions of yellow, magenta and cyan BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a photograph of the appearance showing an example of how to play with polka dots in an example of a polka dot toy using the super water-repellent coating agent of the present invention: (1) Drop one polka dot of a yellow aqueous solution onto a goal, and add a magenta aqueous solution. and (2) vibrating the path frame in any horizontal direction and using a dropper to move the drop of magenta solution along the obstacle. , and (3) a state in which a magenta aqueous solution polka dot is put into the goal and mixed with a yellow aqueous solution polka dot to form a large red aqueous polka dot.

Embodiments of the present invention will be described in detail below, but the present invention is not limited thereto.
<Super water-repellent coating agent>

FIG. 1 is a cross-sectional view schematically showing the structure of a super water-repellent coating obtained with a super water-repellent coating agent according to an embodiment of the present invention.

As shown in FIG. 1, the super water-repellent coating formed by the super water-repellent coating agent of this embodiment has a nano/microscale double surface structure formed of silica nanoparticles whose surfaces are hydrophobized, and the silica nanoparticles It contains an adhesive that bonds between them and between the silica nanoparticles and the substrate surface, and is characterized by being able to improve the durability or adhesion of the super water-repellent coating formed by this adhesive.

In order to realize the structure of the super water-repellent coating of this embodiment shown in FIG. , water (C), a first silane (D), a second silane (E), a catalyst for hydrolysis of the silane (F), and an adhesive (G).

The silica nanoparticles (A) used in the present embodiment are a material for forming a fine uneven structure necessary for imparting superhydrophobicity to the surface coating of the substrate. Silica nanoparticle powder can be used as such silica nanoparticles, but colloidal silica in which silica nanoparticles are colloidally dispersed in a solvent can also be used.

As the silica nanoparticle powder used in the present embodiment, it is preferable to use hydrophobic silica nanoparticles that are perfectly spherical, have a narrow particle size distribution, and have their surfaces subjected to a hydrophobic treatment. Since such hydrophobic silica nanoparticles can be easily dispersed, the superhydrophobic coating agent of the present embodiment can be easily prepared. The average particle size of the hydrophobic silica nanoparticles is preferably 100 nm or less, more preferably 50 nm or less. Specific products include, for example, QSG170, QSG30, and QSG15 manufactured by Shin-Etsu Chemical Co., Ltd.

The colloidal silica used in the present embodiment is preferably hydrophilic silica particles whose surface is not hydrophobized. The shape of the colloidal silica is preferably spherical, and more preferably long and narrow, which is called a chain shape. The average particle size of spherical colloidal silica is preferably 100 nm or less. The chain colloidal silica preferably has an average particle diameter of 5 nm to 30 nm in the minor axis and 20 nm to 200 nm in the major axis, more preferably 10 nm to 15 nm in the minor axis and 40 nm to 100 nm in the major axis. Specific products of spherical colloidal silica include, for example, IPA-ST and IPA-ST-ZL manufactured by Nissan Chemical Industries, Ltd. Specific products of chain colloidal silica include, for example, IPA-ST-UP manufactured by Nissan Chemical Industries. The mass concentration of silica in colloidal silica is preferably 15 wt % or more. The amount of silica particles added in colloidal silica is preferably 0.05 to 5.00 wt%, more preferably 0.10 to 1.50 wt%, relative to the blended mass of the superhydrophobic coating agent.

By increasing the amount of the silica nanoparticles (A) used in the present embodiment, the water repellency of the coating obtained from the prepared water-repellent coating agent can be improved. Since it does not become cloudy and has transparency, the amount of silica nanoparticles (A) added can be optimized.

As the alcohol solvent (B) used in the present embodiment, any one of methanol, ethanol, isopropyl alcohol (IPA), pyrovyl alcohol, isobutyl alcohol, normal butyl alcohol, benzyl alcohol, etc. may be used alone. Ethanol is preferred, although two or more may be used in combination. For example, if methanol is used as a solvent, the drying time of the super water-repellent coating of this embodiment can be shortened compared to ethanol. There are problems leading to blindness and metabolic acidosis. In addition, if isopropyl alcohol is used as a solvent, the super water-repellent coating of this embodiment takes a long time to dry and tends to become cloudy. Ethanol used in the present embodiment is not particularly limited in purity as a solvent, but is preferably 85 wt % or more. For example, mixed ethanol with a purity of 85 wt % or higher can be used. Specific examples of such mixed ethanol products include Mixed Ethanol NP manufactured by Yamaichi Chemical Industry Co., Ltd., and the like. The amount of such mixed ethanol added is preferably 60 to 90 wt %, more preferably 75 to 85 wt %, relative to the blended mass of the superhydrophobic coating agent.

The water (C) used in this embodiment is necessary for the hydrolysis reaction of the silane components (D and E) that chemically modify the surface of the silica nanoparticles (A), and is preferably purified water. For example, both ion-exchanged water and distilled water may be used. The amount of water added is preferably 1 to 30 wt%, more preferably 5 to 20 wt%, relative to the blended mass of the superhydrophobic coating agent. When the amount of water added exceeds the optimum addition amount range, the dispersibility of the super water-repellent coating agent of the present embodiment deteriorates, and the uniformity of the super water-repellent coating tends to deteriorate.

Furthermore, by optimizing the volume ratio of the alcoholic solvent (B) and water (C) used in this embodiment, the uniformity and transparency of the superhydrophobic coating can be improved. The volume ratio of ethanol to water is preferably ethanol:water=5.0 to 10.0, more preferably alcohol:water=6.0 to 8.0.

The first silane (D) used in the present embodiment partially forms hydrophilic silanol groups (≡Si—OH ), preferably tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS). For example, when TEOS is used, the chemical reaction for modifying the surface of silica particles with silanol under alkaline conditions is thought to occur through the following process.
Si( _OCH2CH3 ) _{4 + 4H2O} →
Si(OH) _{4 + 4CH3CH2OH} (1)
Silica particles - (OH) _x + Si(OH) ₄ →
Silica particles-Si(OH) _4-X + xH ₂ O (2)

The above reaction (1) is called the hydrolysis reaction of TEOS, and the above reaction (2) is called the silylation reaction between the silanol produced by the hydrolysis of TEOS and the silica surface. It is thought that the silica particle growth occurs due to the dehydration condensation reaction (3) of silanol described below while the above reaction (2) occurs.
nSi(OH) ₄ →nSiO2 _{+ 2nH2O} (3)

The amount of the first silane (D) added is preferably 0.05 to 3.00 wt%, more preferably 0.15 to 1.00 wt%, relative to the blended mass of the superhydrophobic coating agent. preferable. Specific examples of TEOS products include KBE-04 manufactured by Shin-Etsu Chemical Co., Ltd., and the like.

The second silane (D) used in the present embodiment imparts hydrophobicity to the superhydrophobic coating agent (suspension) in the present embodiment, so that the surface of the silica nanoparticles is partially coated with a hydrophobic hydrocarbon It is modified with a silanol group having a chain, and is preferably a silane compound represented by the following general formula (E-1).

［式（Ｅ－１）中、Ｒはメチル基又はアミン基、メタクリル基又エポキシ基、オレフィン基を表し、Ｒ１はメチル基又はエチル基又はクロロ基を表し、ｎは２価の炭化水素基の数を表し、ｎ＝５以上であることが好ましい。］

[In the formula (E-1), R represents a methyl group, an amine group, a methacrylic group, an epoxy group, or an olefin group; R1 represents a methyl group, an ethyl group, or a chloro group; n represents a divalent hydrocarbon group; It is preferable that n=5 or more. ]

For example, hexyltrimethoxysilane (n=5) (HTMS), dodecyltrimethoxysilane (n=11) (DDTMS), hexadecyltrimethoxysilane (n=15) (HDTMS), octadecyltrimethoxysilane (n=17 ) (ODTMS), hexyltriethoxysilane (n=5) (HTES), dodecyltriethoxysilane (n=11) (DDTES), hexadecyltriethoxysilane (n=15) (HDTES), octadecyltriethoxysilane ( n=17) (ODTES) and the like. Specific products used as the second silane (E) include, for example, KBM-3183 (ODTMS) and X-88-422 (HDTMS) manufactured by Shin-Etsu Chemical Co., Ltd.

When DDTMS is used as the second silane component (E) in the present embodiment, the silylation reaction with silanol on the surface of silica particles under alkaline conditions is thought to occur through the following process.
CH ₃ (CH ₂ ) ₁₁ —Si(OCH ₃ ) ₃ + 3H ₂ O →
_CH3 ( _CH2 ) ₁₁ -Si(OH) ₃ + _3CH3OH (4)
CH ₃ (CH ₂ ) ₁₁ —Si(OH) ₃ + silica particles —(OH) _x →
CH ₃ (CH ₂ ) ₁₁ -Si(OH) _3-x -silica nanoparticles + xH ₂ O (5)

The amount of the second silane (E) added in the present embodiment is preferably 0.01 to 1.50 wt%, more preferably 0.05 to 1.00 wt%, relative to the blended mass of the super water-repellent coating agent. is more preferable. Furthermore, since the mass ratio of the amount of the first silane (D) and the second silane (E) added has a great effect on the coating properties of the super water-repellent coating composition and the water repellency of the coating in this embodiment, The first silane (D):second silane (E) is preferably from 1.0 to 6.0, more preferably from 2.0 to 4.0. Furthermore, in contrast to the combination of the first silane (D) and the second silane (E), for example, if tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS) is used as the first silane (D), , R1 are preferably methyl groups as the second silane (E).

The silane hydrolysis catalyst (F) used in the present embodiment is preferably an alkaline substance. Examples thereof include ammonia water, tetramethylammonium hydroxide (TMAH) aqueous solution, sodium hydroxide, and the like, but ammonia water is more preferable. The concentration of ammonia water is not particularly limited, but the mass concentration is preferably 28% to 30%, and the amount added is 0.1 to 10.0 wt% relative to the blended mass of the super water-repellent coating agent. is preferred, and 1.0 to 5.0 wt% is more preferred. In this embodiment, for example, when 1M nitric acid was used as an acidic catalyst, the prepared dispersion was almost transparent and did not develop turbidity, but the coating obtained with this dispersion did not exhibit superhydrophobicity. This is probably because the dehydration condensation reaction (5) between the silanol produced by the hydrolysis of the second silane and the silanol on the surface of the silica nanoparticles under acidic conditions is much slower than under alkaline conditions. Therefore, in an embodiment, the combination of the first silane (D) and the second silane (E) is used to modify the hydrophilic silica nanoparticle surface to obtain a super water-repellent coating composition, and an alkaline catalyst is used. is preferred.

The adhesive (G) used in this embodiment is soluble in an alcoholic solvent (B) or water (C). And the durability of the super water-repellent coating can be improved by providing bonding force between the silica nanoparticles and the substrate surface. In addition, since the super water-repellent coating agent of the present embodiment provides high safety to the human body and imparts transparency to the super water-repellent coating made of the super water-repellent coating agent, it is friendly to the environment and the human body. Polymeric adhesives are preferred. Examples thereof include polyacrylic acid (PAA), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyvinyl butyral (PVB) and the like. Any one of these water-soluble adhesives and water-insoluble adhesives may be used alone, or one kind of water-soluble adhesive and one kind of water-insoluble adhesive may be used in combination. In order to impart the dispersibility of silica particles in the super water-repellent coating agent and improve the durability of the super water-repellent coating made of the super water-repellent coating agent, the molecular weight of the polymer adhesive used in this embodiment is It is preferably 10,000 or more, more preferably 20,000 or more. When polyacrylic acid (PAA) is used, specific products include Julimer AC-10L and Julimer AC-10H manufactured by Toagosei Co., Ltd. When polyvinyl butyral (PVB) is used, specific products include Mowital B 30H and Mowital B 60H manufactured by Kuraray.

The method of using the adhesive (G) used in this embodiment is that, for a water-soluble adhesive, for example, if the polyacrylic acid (PAA) product is not an aqueous solution but a powder, an aqueous solution of PAA is prepared in advance. It is preferable to keep The mass concentration of the PAA aqueous solution is preferably 2 wt % or more, more preferably 5 wt % or more. Even for water-insoluble adhesives, for example, if polyvinyl butyral (PVB) is a powder rather than a solvent solution, it is preferable to prepare a PVB solvent solution (eg, ethanol) in advance. The mass concentration of the PVB solvent solution is preferably 5 wt % or more, more preferably 10 wt % or more. In the present embodiment, as the amount of the adhesive (G) added increases, the durability or adhesion of the prepared superhydrophobic coating improves, but there is a problem of loss of superhydrophobicity and transparency. be. Therefore, the amount of the adhesive (G) to be added is preferably 1.0 to 300.0 wt%, more preferably 5.0 to 50.0 wt%, relative to the compounded mass of the silica nanoparticles in the superhydrophobic coating agent. is more preferable. In this embodiment, water-soluble PAA was used as an adhesive, and it was found that the water resistance of the obtained superhydrophobic coating is related to the amount of PAA added and the surface properties of silica nanoparticles. When using hydrophilic silica nanoparticles (for example, IPA-ST-UP manufactured by Nissan Chemical Industries, Ltd.) as a raw material, the amount of PAA added is less than or greater than the optimum amount, and the resulting super water-repellent coating is water resistant. I discovered that I didn't have it. In an alkaline solution, the PAA molecules are completely anionized and become insoluble in a mixed solution of ethanol and water, and the PAA molecules form reverse micelles in the ethanol solution. presumed to have sex. Moreover, when hydrophobic silica nanoparticles (for example, QSG30 manufactured by Shin-Etsu Chemical Co., Ltd.) were used as raw materials, the resulting super water-repellent coating did not exhibit water resistance regardless of the amount of PAA added. Since the surface of the silica nanoparticles of QSG30 is hydrophobic, the hydrophobic groups of PAA face the hydrophobic surface of the silica nanoparticles, so the hydrophilic groups of PAA (-COOH or -COO-) face the ethanol solution side, and the reverse micelle is formed. Assume that it cannot be formed.
<Method for producing super water-repellent coating agent>

FIG. 2 is a flowchart showing an example of a method for producing a super water-repellent coating agent according to this embodiment.

A method for producing a super water-repellent coating agent according to the present embodiment, a first step of adding an alcohol-based solvent (B) to a production vessel, adding silica nanoparticles (A) while stirring the solvent, and dispersing them; A second step of adding and dissolving the first silane (D) and the second silane (E) while stirring the dispersion liquid consisting of the steps, and water (C) while stirring the dispersion liquid consisting of the second step. and a third step of adding an adhesive (G) and a catalyst (F).

The order of adding raw materials in each step in the production method of the present embodiment is not particularly limited, but in the second step of the production method, the order of the first silane (D) → the second silane (E) is preferable. . In the third step of the manufacturing method, it is preferable that the order is water (C)→adhesive (G)→catalyst (F).

In the three steps in the manufacturing method of the present embodiment, the stirring method or stirring device is not particularly limited. A stirrer called a magnetic stirrer may be used, in which a stirrer coated with Teflon or the like containing a magnet is rotated from the outside of the container to transmit power by a magnetic field. A stirrer called a mechanical stirrer that stirs via a stirrer may be used.

In the three steps of the production method of the present embodiment, the stirring method or stirring device is not particularly limited, but the stirring speed depends on the dispersibility of the silica nanoparticles and the hydration of the first silane (D) and the second silane (E). It has a great influence on the decomposition rate and the dehydration condensation rate, so it needs to be controlled. When a magnetic stirrer is used, a 200 ml triangular beaker is used as a container, and in order to produce 80 g of the super water-repellent coating agent of this embodiment, when a stirrer with a size of Φ8×30 mm is used, the stirring speed is 400 rpm or more. It is preferably 800 rpm or more, more preferably 800 rpm or more. When using a mechanical stirrer or a mechanical stirrer, a 2000 ml plastic bottle (Φ126 x 254 mm) is used as a container, and in order to produce 1000 g of the super water-repellent coating agent, a movable two-bladed stirrer with a blade width of 100 mm during rotation is used. If used, the stirring speed is preferably 200 rpm or higher, more preferably 400 rpm or higher.

In the first step of the production method of the present embodiment, after the silica nanoparticles are added, the stirring time is preferably 5 minutes or longer, more preferably 10 minutes or longer, in order to sufficiently disperse the silica nanoparticles in the solvent. is more preferred. In the second step of the production method, after adding the first silane (D) and the second silane (E), the two silanes are completely dissolved in the solvent dispersion of silica nanoparticles in the first step. , the stirring time is preferably 5 minutes or longer, more preferably 10 minutes or longer. The third step of the production method is a step of chemically modifying the surface of the silica nanoparticles by hydrolyzing and condensing the silane. It is preferably at least 1 hour, more preferably at least 24 hours. If the hydrolysis/condensation reaction of the silane is insufficient, the coating formed from the produced coating agent may not have super water repellency.

Temperature conditions in all steps of the manufacturing method of the present embodiment are not particularly limited. It may be room temperature, or may be heated up to 60°C.

In addition, the order of steps in the manufacturing method of the present embodiment is not limited to the order of first step→second step→third step. The super water-repellent coating in this embodiment can be manufactured in the order of the first step→the third step→the second step. When the superhydrophobic coating of the present invention is produced in the order of the first step → third step → second step, in the step of adding the first silane (D) and the second silane (E), the first silane (D ) and the second silane (E) are preferably added at slow rates. For example, when the production amount of the super water-repellent coating agent is 1000 kg, the addition rates of the first silane (D) and the second silane (E) are 2.5 L/h and 0.9 L/h or less, respectively. 1.5 L/h and more preferably 0.5 L/h or less.

In the production method of the present embodiment, when aqueous ammonia is used as the catalyst (F) for hydrolysis of silane, it is necessary to remove the ammonia odor from the superhydrophobic coating agent obtained in the third step. A deodorizing step called the fourth step of can be added. Although the deodorization method is not particularly limited, it is preferably a bubbling method called an ammonia stripping method in which a carrier gas is used to vaporize the liquid in the liquid material container. The operating temperature in the deodorizing step by the bubbling method is not particularly limited, but is preferably above 30°C, more preferably above 50°C.

FIG. 3 is a photograph of the appearance of a sample showing an example of a super water-repellent coating produced by the production method of the present embodiment.

The superhydrophobic coating agent produced by the production method of the present embodiment may undergo precipitation or phase separation during storage.

In addition, the super water-repellent coating agent produced by the production method of the present embodiment has amphipathic properties, so that it can be used in any shape of glass, ceramics, porcelain tiles, baked tiles, metals, wood, plastics, paper, and A superhydrophobic coating can be formed on the surface of a cloth or the like. Further, the superhydrophobic coatings formed on the surfaces of the various substrates are characterized by transparency and durability.
<Method for forming superhydrophobic coating>

The method of forming a super water-repellent coating using the super water-repellent coating agent according to the present embodiment is very simple, and is characterized by a one-step coating that can be used by natural drying without the need for high-temperature drying or heating. do.

Although the method of applying the super water-repellent coating agent according to the present embodiment is not particularly limited, it is preferably spray coating. Specific spray application methods include, for example, a spray bottle, a spray can (aerosol type), and a spray gun.

The conditions for drying the super water-repellent coating formed from the super water-repellent coating agent according to this embodiment are not particularly limited. It may be natural drying, a dryer, or a drying apparatus. In the case of natural drying, the drying time is preferably 4 hours or longer, more preferably 8 hours or longer, and most preferably 24 hours.

In order to form a super water-repellent coating by a spray coating method using the super water-repellent coating agent according to this embodiment, the number of times of spraying may vary depending on the target material and surface condition. A dense, smooth surface requires fewer sprays to form a superhydrophobic coating than a porous, uneven surface. For example, when coating glass or ceramic tiles, it is preferable that the number of times of spraying is 6 or more in the same place. When applying to a corrugated board or wood surface, it is preferable that the number of times of spraying is 12 or more in the same place.
<Toys using super water-repellent coating agent>

The super water-repellent coating agent according to the present embodiment does not contain a fluorine component, does not contain a petroleum-based solvent that is harmful to health and has an irritating odor, and can easily form a super water-repellent coating on various substrate surfaces. It is characterized and applied to make a super water-repellent coating that forms polka dots to play with.

A toy using the super water-repellent coating agent according to the present embodiment includes at least a super water-repellent coating agent (T1), an application tool (T2), an infusion tool (T3), and a coloring solution (T4). , but not limited to these.

In the toy using the super water-repellent coating agent according to this embodiment, the material and shape of the applicator (T2) are not particularly limited. A superhydrophobic coating can be formed on surfaces such as glass, ceramics, porcelain tiles, fired tiles, metals, wood, cardboard, plastics, and fabrics of any shape. The shape of (T2) of the tool for playing with polka dots may be a simple surface, a sphere, or a doll. ), it may be in the form of a complex maze.

In the toy using the superhydrophobic coating agent according to the present embodiment, the infusion tool (T3) is not particularly limited. Any dripping method may be used as long as the solution is dripped intermittently to form droplets on the superhydrophobic coating applied to the coating tool (T2). Specific infusion methods include, for example, a dropper, a syringe, and an infusion bottle.

In the toy using the super water-repellent coating agent according to the present embodiment, the coloring solution (T4) includes yellow, magenta, and cyan colors. More preferably there is a coloring solution of the three primary colors of the material. These three primary colored solutions can be prepared from colorants. As a method for preparing the coloring solution, for example, Food Blue No. 1, Food Red No. 105, and Food Yellow No. 4 are added to water at mass concentrations of 0.565 wt%, 0.423 wt%, and 0.571 wt%, respectively. When dissolved, yellow, magenta and cyan solutions can be obtained.

EXAMPLES Next, the present invention will be described in more detail based on examples, but the present invention is not limited to these. Detailed compounding ratios in Examples will be described later in Tables 1 to 3 and FIGS. 4 to 11 together with evaluation results.
<Preparation of super water-repellent coating agent and formation of super water-repellent coating>

Place a 200 ml triangular beaker on a magnetic stirrer, add 81.48 g of mixed ethanol NP (B) as a solvent, add 13.06 g of ion-exchanged water (C) and 2.35 g of ammonia water (F), and stir at a stirring speed of 800 rpm. After stirring the mixture for 10 min, 2.61 g of colloidal silica IPA-ST-UP (A) was added, and after stirring for 10 min at the same stirring speed, 0.37 g of TEOS (D) and 0.3 g of DDTMS (E) were added. A super water-repellent coating agent was prepared by adding 13 g and stirring at room temperature for 24 hours. A slide glass (75 mm x 25 mm) used as a substrate was cleaned with ethanol using ultrasonic waves and dried at 120°C. 0.5 ml of the superhydrophobic coating agent prepared above was spread on the surface of the slide glass with a dropper and dried at 40° C. for 30 minutes to obtain a coating on the surface of the slide glass.

A superhydrophobic coating agent was prepared by changing the addition of ion-exchanged water (C) and ammonia water (F) to the addition of colloidal silica IPA-ST-UP in contrast to Example 1.

A superhydrophobic coating agent was prepared by changing the addition of TEOS (D) and DDTMS (E) to after addition of ion-exchanged water (C) and ammonia water (F) in contrast to Example 2.

In addition to Example 2, 0.78 g of 5 wt% Jurimer AC-10L was added as an adhesive (G), and 10 wt% was added to the silica nanoparticles (solid content) in the super water-repellent coating agent composition to form a super water-repellent coating agent. made.

A superhydrophobic coating agent was prepared by changing the addition of TEOS (D) and DDTMS (E) to after addition of ion-exchanged water (C) and ammonia water (F) in contrast to Example 4.

The method of Example 5 was changed to a spray coating method using a spray bottle to prepare a coating on the slide glass surface.

Compared to Example 5, 5 wt% Jurimer AC-10L was used as an adhesive (G), and the amount was reduced to 1 wt% with respect to the silica nanoparticles (solid content) in the super water-repellent coating composition to produce a super water-repellent coating agent. bottom.

Compared to Example 5, 5 wt% Julimer AC-10L was used as an adhesive (G) and increased to 50 wt% with respect to the silica nanoparticles (solid content) in the super water-repellent coating agent composition to form a super water-repellent coating agent. made.

In contrast to Example 5, 5 wt% Julimer AC-10L was used as an adhesive (G), and the amount was reduced to 100 wt% with respect to the silica nanoparticles (solid content) in the super water-repellent coating agent composition to produce a super water-repellent coating agent. bottom.

In contrast to Example 9, the total amount of TEOS (D) and DDTMS (E) was the same, and the mass ratio of TEOS (D) and DDTMS (E) was changed from 2.8 to 1.6. A water-repellent coating agent was produced.

Compared to Example 9, the total amount of TEOS (D) and DDTMS (E) was the same, and the mass ratio of TEOS (D) and DDTMS (E) was changed from 2.8 to 1.0. A water-repellent coating agent was produced.

A super water-repellent coating agent was prepared by changing the amount of DDTMS (E) to 5 times that of Example 9 with the same TEOS (D).

A super water-repellent coating agent was prepared by changing the amount of DDTMS (E) to 10 times that of Example 9 with the same TEOS (D).

0.39 g of 10 wt% Mowital B 30H ethanol solution was added as adhesive (G), except that 0.78 g of 5 wt% Jurimer AC-10L was added as adhesive (G) to Example 5. was adjusted to 20 wt % based on the silica nanoparticles (solid content) in the super water-repellent coating composition to prepare a super water-repellent coating agent.

Compared to Example 14, the amount of ion-exchanged water (C) was reduced, and the volume ratio of ethanol (B) and water (C) was changed from 7.3 to 9.2 to prepare a super water-repellent coating agent. .

Compared to Example 14, 5 wt% Jurimer AC-10L was not added as adhesive (G), the total amount of adhesive (G) was the same, and 0.78 g of 10 wt% Mowital B 30H ethanol solution was added alone. , a superhydrophobic coating agent was prepared.

Compared to Example 16, the amount of ion-exchanged water (C) was reduced, and the volume ratio of ethanol (B) and water (C) was changed from 7.3 to 9.1 to prepare a super water-repellent coating agent. .

Compared to Example 14, the blending amount of 5 wt% Jurymer AC-10L was the same, the blending amount of 10 wt% Mowital B 30H ethanol solution was quadrupled, and the total blending amount of adhesive (G) was a super water-repellent coating agent. A super water-repellent coating agent was prepared with 50 wt % of the silica nanoparticles (solid content) in the composition.

Compared to Example 15, the blending amount of 5 wt% Jurymer AC-10L was the same, the blending amount of 10 wt% Mowital B 30H ethanol solution was increased by 9 times, and the total amount of adhesive (G) blended was a super water-repellent coating agent. A super water-repellent coating agent was prepared with 100 wt % of the silica nanoparticles (solid content) in the composition.

Compared to Example 19, the amount of ion-exchanged water (C) was increased, and the volume ratio of ethanol (B) and water (C) was changed from 9.2 to 7.3 to prepare a super water-repellent coating agent. .

Compared to Example 19, the amount of ion-exchanged water (C) was increased, and the volume ratio of ethanol (B) and water (C) was changed from 9.2 to 6.0 to prepare a super water-repellent coating agent. .

Compared to Example 19, the amount of ion-exchanged water (C) was increased, and the volume ratio of ethanol (B) and water (C) was changed from 9.2 to 5.1 to prepare a super water-repellent coating agent. .

In contrast to Example 5, DDTMS (E) as the second silane was changed to HDTMS to prepare a super water-repellent coating agent.

In contrast to Example 5, DDTMS (E) as the second silane was changed to ODTMS to prepare a super water-repellent coating agent.

To Example 21, 0.39 g of a 10 wt% Mowital B 60H ethanol solution was added alone as an adhesive (G), and the blend amount was 10 wt relative to the silica nanoparticles (solid content) in the super water-repellent coating composition. % to prepare a super water-repellent coating agent. A coating was prepared on the slide glass surface by changing to a spray coating method using a spray bottle.

Compared to Example 25, the amount of 10 wt% Mowital B 60H ethanol solution as the adhesive (G) was tripled, and the amount was equal to the silica nanoparticles (solid content) in the super water-repellent coating composition. A super water-repellent coating agent was prepared with 30 wt %.

With respect to Example 25, the amount of 10 wt% Mowital B 60H ethanol solution as the adhesive (G) was increased by 5 times, and the amount of silica nanoparticles (solid content) in the super water-repellent coating composition A super water-repellent coating agent was prepared with 50 wt %.

In contrast to Example 27, the 10 wt% Mowital B 60H ethanol solution as the adhesive (G) was changed to a 10 wt% Mowital B 30H ethanol solution, and the amount of silica nanoparticles in the super water-repellent coating composition (solid content ) to 100 wt % to prepare a super water-repellent coating agent.

In contrast to Example 28, the drying of the coating on the surface of the slide glass was changed from 40° C.×30 min to 4 hours at room temperature.

A super water-repellent coating agent was prepared by simultaneously doubling the blending amounts of colloidal silica IPA-ST-UP (A), TEOS (D) and ODTMS (E) relative to Example 25. The method of coating the surface of the slide glass was changed to the method of spreading with a dropper.

A superhydrophobic coating agent was prepared by simultaneously increasing the blending amounts of colloidal silica IPA-ST-UP (A), TEOS (D) and ODTMS (E) to 2.5 times that of Example 30.

In contrast to Example 5, a superhydrophobic coating agent was produced by changing the mixed ethanol NP as the solvent (B) to 99.5% ethanol.

A superhydrophobic coating agent was produced by changing TEOS as the second silane (D) to TMOS in contrast to Example 5.

In contrast to Example 5, a superhydrophobic coating agent was produced by changing the mixed ethanol NP as the solvent (B) to IPA. The coating on the slide glass surface was dried at 40° C. for 1 hour.

In contrast to Example 34, 5 wt% Jurimer AC-10L as the adhesive (G) was changed to 10 wt% Mowital B 30H ethanol solution, and the amount of silica nanoparticles (solid content) in the super water-repellent coating composition was changed. to 100 wt% to prepare a super water-repellent coating agent.

In Example 6, tiles, wood, corrugated cardboard, SUS304, and acrylic resin were used as materials in place of the slide glass to produce a super water-repellent coating. As shown in Table 2, all substrates gave uniform superhydrophobic coatings with good adhesion, water resistance and transparency.

(Comparative example 1)
In contrast to Example 5, a super water-repellent coating agent was prepared by using silane (D) and silane (E) as a hydrolysis catalyst (F) and using 1M nitric acid instead of aqueous ammonia.

(Comparative example 2)
Compared to Example 5, the stirring speed was changed from 800 rpm to 400 rpm to prepare a super water-repellent coating agent.

(Comparative Example 3)
A superhydrophobic coating agent was prepared by changing the stirring time from 24 hours to 4 hours in comparison with Example 5.

(Comparative Example 4)
A super water-repellent coating agent was prepared by replacing 5 wt % Julimer AC-10L as the adhesive (G) with 5 wt % PVA in contrast to Example 5.

(Comparative Example 5)
A super water-repellent coating agent was prepared in Example 5 by changing 5 wt % Julimer AC-10L as the adhesive (G) to 5 wt % PVP.

(Comparative Example 6)
In contrast to Example 1, DDTES was used as the second silane (E) instead of DDTMS to produce a super water-repellent coating agent.

(Comparative Example 7)
In contrast to Comparative Example 1, a superhydrophobic coating agent was prepared by using TMOS and DDTES as the first silane (D) and the second silane (E) instead of TEOS and DDTMS, respectively.

(Comparative Example 8)
In contrast to Example 1, IPA-ST-ZL was used as the silica nanoparticles (A) instead of IPA-ST-UP to prepare a super water-repellent coating agent.

(Comparative Example 9)
In contrast to Example 1, IPA-ST was used as the silica nanoparticles (A) instead of IPA-ST-UP to prepare a super water-repellent coating agent.

(Comparative Example 10)
For Examples 1 to 35, using hydrophobic silica nanoparticles QSG170 instead of hydrophilic silica nanoparticles IPA-ST-UP as silica nanoparticles (A), place a 200 ml triangular beaker on a magnetic stirrer, and mix ethanol NP43. 0.58 g was added as a solvent (B), and while stirring at a stirring speed of 800 rpm, 0.56 g of QSG170 was added and dispersed to prepare a super water-repellent coating agent.

(Comparative Example 11)
In contrast to Comparative Example 10, a super water-repellent coating agent was produced using QSG30 instead of QSG170 as the silica nanoparticles (A).

(Comparative Example 12)
To Comparative Example 11, 0.55 g of a 10 wt % Mowital B 30H ethanol solution was added as an adhesive (G) to prepare a super water-repellent coating agent.

evaluation

In Examples 1 to 36 and Comparative Examples 1 to 12, the uniformity, water resistance, adhesion and transparency of the coating on the applied slide surface were evaluated according to the following three-level evaluation criteria of S, A, and B. evaluated. The water repellency of the coating was evaluated according to a four-grade scale of S, A, B, and none.

<Coating Uniformity>
<S>: Uncoated areas and white unevenness are not observed <A>: Uncoated areas and white unevenness are slightly observed, but not noticeable <B>: Uncoated areas and white unevenness are conspicuous

<Water resistance of coating>
<Yes>: Even after 10 minutes have passed after a water droplet is placed on the coating, the coating does not dissolve and the shape of the water droplet does not change. end up

<Coating Adhesion>
<S>: Coating does not come off when rubbed with fingertips <A>: Coating comes off when rubbed with fingertips, but hardly comes off with adhesive tape <B>: Coating comes off when lightly touched with fingertips, can be removed with adhesive tape is clearly recognized

<Coating transparency>
<S>: White letters written on paper with a black background look beautiful, and there is almost no change compared to the original color of the base material <A>: White letters written on paper with a black background Although the characters cannot be seen clearly, they can be identified, and compared to the original color of the base material, it is recognized that they have become slightly whiter <B>: Identify white characters written on paper with a black background not possible and noticeably whitened compared to the original color of the substrate

<Water repellency of coating>
<S>: Super water-repellent state where water droplets roll when 10 μL of water droplets are dropped on the horizontal coating with a syringe <A>: When 10 μL of water droplets are dropped on the horizontal coating with a syringe, the water droplets do not roll, but the inclination angle is 10° Super water-repellent state <B>: When a water droplet of 10 μL is dropped on a horizontal coating with a syringe, the water droplet does not roll, but it does not roll even if the tilt angle is increased to 10°. 〈None〉: The coating shows water repellency at first, but the coating melts over time and the water repellency is lost.

<Contact angle measurement>
The water repellency of the prepared coating was evaluated by measuring the contact angle with respect to water droplets. About 10 μL of water droplets were dropped on the prepared coating with a syringe, and the state of the water droplets was photographed, and the contact angle was measured using ImageJ image analysis software.

From Examples 1 to 5 in Table 1-1, it can be seen that the uniformity and transparency of the coating can be improved depending on the order in which the raw materials are added. By using PAA(G) as an adhesive, the adhesion and superhydrophobicity of the coating can be improved. According to Example 6, the prepared superhydrophobic coating agent can be applied by a simple spray coating method.

From Examples 7 to 13 in Table 1-1, it becomes clear that when PAA (G) is used as an adhesive, the amount of PAA added has a great effect on the water resistance of the superhydrophobic coating. When the mass ratio of PAA (G) and silica nanoparticles (A) is 0.5 or more and 0.1 or less, superhydrophobicity is achieved regardless of the amount of the second silane (E) that hydrophobilizes and modifies the silica particle surface. The coating loses water resistance.

From Example 14 in Table 1-1, Example 15 in Table 1-2, and Examples 18-22, water-soluble PAA and water-insoluble PVB can be used together as an adhesive. Furthermore, by increasing the amount of PVB added until the mass ratio of the adhesive (G) and silica nanoparticles is 1.0, the resulting super water-repellent coating has improved adhesion while maintaining super water repellency. can be done. Also, from Examples 19-22, the volume ratio of ethanol (B) and water (C) can improve the uniformity of the resulting superhydrophobic coating. When the volume ratio of ethanol (B) and water (C) is 7.3 or more and 6.0 or less, the uniformity of the superhydrophobic coating tends to deteriorate.

From Examples 22 to 24, the uniformity and water repellency of the super water-repellent coating were improved by increasing the number n of divalent hydrocarbon groups in the second silane compound (E) shown in [Formula] (E-1). tend to improve. From Examples 25-27, the uniformity and adhesion of the superhydrophobic coating can be improved by using PVB with higher molecular weight as the adhesive. However, when the amount of PVB added exceeds 30 wt % with respect to the silica nanoparticles, the superhydrophobicity tends to be lost. From Example 28, if PVB with a lower molecular weight is used, even if the added amount of PVB is up to 100 wt% with respect to the silica nanoparticles, both the uniformity and water repellency of the superhydrophobic coating can be improved. .

From Example 29 in Tables 1-3, the super water-repellent coating using PVB can be dried at room temperature for 4 hours. From Examples 30 and 31, it can be seen that when ODTMS is used as the second silane (E) and PVB is used as the adhesive, the uniformity and superrepellency of the superhydrophobic coating are improved even when the amount of hydrophilic linear colloidal silica is increased. Aqueous can be obtained. From Examples 5 and 32, using high-purity ethanol and mixed ethanol as the solvent (B) did not significantly affect the performance of the superhydrophobic coating. From Example 33, using TMOS as the first silane (D) makes it possible to prepare a superhydrophobic coating. From Examples 34 and 35, it is possible to prepare a super water-repellent coating agent even if IPA is used as the solvent (B).

From Comparative Example 1 in Table 3, an acidic catalyst cannot be used to prepare the super water-repellent coating composition of the present invention. When a super water-repellent coating agent was prepared from Comparative Example 2 at a stirring speed of 400 rpm, the resulting coating did not exhibit super water repellency. From Comparative Example 3, when the stirring speed was 800 rpm and the stirring time was insufficient, the obtained coating did not have super water repellency. From Comparative Examples 5 and 6, when nonionic water soluble PVA and PVP were used as adhesives, the resulting coatings were not water resistant and did not provide water repellency. From Comparative Examples 6 and 7, when the second silane compound (E) shown in [Formula] (E-1) in which R1 is methyl was used, the resulting coating did not exhibit super water repellency. From Comparative Examples 8 and 9, larger spherical colloidal silica IPA-ST-ZL (average particle size 70 to 100 nm) and smaller spherical colloidal silica IPA-ST (average particle size 10 to 15 nm) than linear colloidal silica IPA-ST-UP ), the resulting coating was poorly uniform and did not provide superhydrophobicity.

From Comparative Examples 10 to 12 in Table 3, when using hydrophobic spherical silica nanoparticles, if the average particle size is about 30 nm, it is possible to prepare a super water-repellent coating agent by dispersing it in a mixture of ethanol and water. However, if an adhesive is used to improve the adhesion of the coating, the superhydrophobicity of the coating is lost.

<Adhesion test>
Adhesion of the prepared superhydrophobic coating was evaluated by the adhesive tape method. The appearance and water repellency of the coating of the unpeeled portion and the peeled portion are compared and evaluated. As shown in FIG. 8, the super water-repellent coating on the slide glass surface using PAA as an adhesive (Example 6) showed almost no change in coating appearance even when peeled off with an adhesive tape. Furthermore, the superhydrophobicity was almost unchanged.

<Water resistance test>
The water resistance of the produced super water-repellent coating was evaluated as follows. About 50 ml of hot water (~38°C) was added to a 100 ml beaker, and the test piece was placed and immersed. The immersed portion was slightly higher than half of the specimen. After the immersion, the opening of the beaker was wrapped and left in a drier at 40°C for 68 hours. About 50 ml of hot water (~90°C) was added to a 100 ml beaker, and the test piece was immersed for 3 minutes as in the previous experiment. The coating appearance and water repellency of the non-immersed side and the immersed side were compared. As shown in FIG. 9, the super water-repellent coating on the surface of the slide glass using PAA as an adhesive (Example 6) showed almost no change in coating appearance even after being immersed in hot water at 40°C for 68 hours. rice field. There was almost no change in the superhydrophobicity. Furthermore, almost no change in coating appearance was observed even after immersion in hot water at 90°C for 3 minutes. There was almost no change in the superhydrophobicity.
<Polka dot toy using super water-repellent coating and how to play>

As shown in FIG. 10, as an example of a polka dot toy using the super water-repellent coating agent of the present invention, a super water-repellent spray coating agent (T1), a channel tool (T2), a drip dropper (T3), Three colored solutions (T4) of yellow, magenta and cyan are included. Food Blue No. 1, Food Red No. 105, and Food Yellow No. 4 were dissolved in water at mass concentrations of 0.565 wt%, 0.423 wt%, and 0.571 wt%, respectively, and yellow, magenta, and cyan A solution was prepared. The frame of the path was made of wood. An iron sheet to which the magnets are attached was used as the substrate. A magnet was attached to one end of the wood block. As a result, after placing a wooden block on the substrate as an obstacle in a predetermined shape, using a super water-repellent coating agent, the iron substrate, the inner wall of the wooden frame and the surface of the wooden block were sprayed 15 times each, It was dried with a drier to prepare a path tool that forms polka dots.

How to play with polka dots will be described as an example shown in FIG. As shown in FIG. 11(1), a dropper was used to drop one drop of yellow aqueous solution onto the goal, and one drop of magenta aqueous solution was dropped onto an arbitrary spot other than the goal. Next, as shown in FIG. 11(2), the path tool was vibrated in an arbitrary horizontal direction, and a dropper was used to move the drop of magenta aqueous solution along the obstacle until it reached the entrance of the goal. . Finally, as shown in FIG. 11(3), the magenta aqueous solution polka dots were placed in a goal and mixed with the yellow aqueous polka dots to form larger red aqueous polka dots.

T1 Super water-repellent coating agent T2 Application tool T3 Drip tool T4 Coloring solution a Appearance of the coating film with adhesive tape attached b Appearance of the coating film with the adhesive tape removed and repelled polka dots c 68 hours in hot water at 40 ° C Appearance of the coating film after immersion and appearance of repelled polka dots d Appearance of the coating film and repelled polka dots after immersion in hot water at 90°C for 3 minutes One droplet was dropped on an arbitrary place other than the goal 2. By vibrating the path frame in an arbitrary horizontal direction and using a dropper, the droplet of magenta aqueous solution was moved along the obstacle to the entrance of the goal. State 3 A magenta water drop is put into the goal, and it mixes with a yellow water drop to form a large red water drop.

Claims (16)

A super water-repellent coating agent used for forming a super water-repellent coating that forms rolling drops on different substrate surfaces, comprising at least one silica nanoparticle (A), an alcoholic solvent (B), and water (C), a first silane (D), a second silane (E), a silane hydrolysis catalyst (F), and an adhesive (G),
The silica nanoparticles (A) have an elongated shape with an average minor axis of 5 nm to 30 nm and an average major axis of 20 nm to 200 nm, are hydrophilic, and have a ratio of 0.10 to 5.0 nm with respect to the blended mass of the superhydrophobic coating agent. 00 wt%,
The alcohol-based solvent (B) may be any one of methanol, ethanol, isopropyl alcohol (IPA), isobutyl alcohol, normal butyl alcohol, benzyl alcohol, etc., either alone or in combination of two or more. , 60 to 90 wt% with respect to the blended mass of the super water-repellent coating agent,
The water (C) is purified water and is 1 to 30 wt% with respect to the blended mass of the super water-repellent coating agent,
The volume ratio of the alcohol solvent (B) and water (C) is alcohol: water = 5.0 to 10.0,
The first silane (D) is tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS), and is 0.05 to 3.00 wt% with respect to the blended mass of the superhydrophobic coating agent,
The second silane (E) is a non-fluorine-based silane compound represented by the following general formula (E-1), and is 0.01 to 1.50 wt% relative to the blended mass of the super water-repellent coating agent. , non-fluorine-based super water-repellent coating agent.

[In the formula (E-1), R represents a methyl group or an amine group, a methacrylic group or an epoxy group, or an olefin group, R1 represents a methyl group, an ethyl group, or a chloro group, and n represents a divalent hydrocarbon group. represents a number, n=5 or more. ] The mass ratio of the amount of the first silane (D) and the second silane (E) added is first silane:second silane=1.0 to 6.0, and tetraethoxysilane (TEOS) or tetramethoxysilane ( TMOS) as the first silane (D), and the second silane (E) is a silane compound in which R1 is a methyl group. 2. The super water-repellent coating agent according to claim 1, wherein the silane hydrolysis catalyst (F) is aqueous ammonia, and the amount thereof is 0.1 to 10.0 wt % relative to the blended mass of the super water-repellent coating agent. The adhesive (G) is water-soluble polyacrylic acid (PAA) or water-insoluble polyvinyl butyral (PVB), any of which has a molecular weight of 10,000 or more, and either of which can be used alone or in combination. , 1.0 to 300.0 wt% of the silica nanoparticles (A) in the super water-repellent coating agent. 2. The method for producing a super water-repellent coating agent according to claim 1, comprising a first step of adding and dispersing silica nanoparticles (A) while stirring the alcoholic solvent (B), A second step of adding and dissolving the first silane (D) and the second silane (E) while stirring the dispersion, and while stirring the dispersion of the second step, water (C) and including a third step of adding an adhesive (G) and a catalyst (F) respectively,
Alternatively, a method for producing a super water-repellent coating agent, which includes a deodorizing step called a fourth step for removing the ammonia odor of the super water-repellent coating agent consisting of the above three production steps. 5. The stirring speed is 400 rpm or more in the three production steps, and the stirring time is 4 hours or more after adding water (C), adhesive (G) and catalyst (F) in the third step. A method for producing the super water-repellent coating agent according to 1. The method for producing a super water-repellent coating agent according to claim 5, wherein the deodorizing method used in the deodorizing step is a bubbling method and the temperature is 30°C or higher. 6. The super water-repellent coating agent according to claim 1, which is produced by the production method according to claim 5 and undergoes precipitation or phase separation during storage, but can be sufficiently redispersed simply by shaking by hand. It is manufactured by the manufacturing method according to claim 5, and a one-step spray coating method does not require high-temperature drying or heating, and can form a super water-repellent coating having transparency and durability by natural drying. Item 1. The superhydrophobic coating agent according to item 1. 6. The super water-repellent coating agent according to claim 1, wherein the super water-repellent coating formed by the manufacturing method according to claim 5 can be reapplied as it is on a portion according to need. For the superhydrophobic coating produced and formed by the production method according to claim 5, if necessary, it can be easily removed with a daily detergent or an alcohol-containing solution, and the superhydrophobic coating is formed again. A superhydrophobic coating according to claim 1, which can be formed. It is manufactured by the manufacturing method according to claim 5, and can easily form a superhydrophobic coating on the surface of arbitrary shaped glass, ceramics, porcelain tiles, baked tiles, metals, wood, plastics, paper, cloth, etc. The super water-repellent coating agent according to claim 1, wherein Claim 1, which is produced by the production method according to claim 5, does not contain a fluorine component, does not contain a petroleum solvent that is harmful to health and has an irritating odor, and can provide a polka dot toy or a way to play with polka dots. Water-repellent coating agent. The polka dot toy comprises at least the super water-repellent coating agent according to claim 1, an applicator, an infusion tool, and a coloring solution, such as a lotus leaf rolling polka dots on the applicator, which is made of different materials. A polka dot toy whose surface can be easily made anywhere and a sense of accomplishment can be enjoyed by reproducing the lotus effect with one's own hands while enjoying the rolling polka dots. 15. The polka dot toy of claim 14, wherein said applicator tool is reusable. The coloring solution is a colorant of three primary colors of yellow, magenta (magenta), and cyan (cyan), and three types of coloring solutions representing the three primary colors of the colorant 15. The polka dot toy of claim 14, wherein there is a

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