JP2013166958A - Aqueous coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous coating material capable of reducing labor in storage, distribution and the like and exhibiting excellent antifouling properties in a formed coating film.SOLUTION: A coating material includes a synthetic resin emulsion (A), water-dispersible silica (B) with a grain size of 1-200 nm, and a fluorine-containing compound (C) having a polyfluoroalkyl group and a nonionic/amphoteric hydrophilic group as essential components. The components (A), (B), and (C) are mixed at the following mixing ratios to the total amount of the coating material: a solid content in the component (A) is 1-50 wt.%; a solid content in the component (B) is 0.1-40 wt.%; and the component (C) is 0.01-3.0 wt.%.

Description

The present invention relates to a novel aqueous coating material. The aqueous coating material of the present invention is particularly suitable as an aqueous coating material for outdoor use.

  In recent years, with respect to coating materials used for painting work such as buildings and civil engineering structures, a shift from solvent-type coating materials using an organic solvent as a solvent to water-based coating materials using a solvent as a solvent is being attempted. This is performed for the purpose of reducing the health hazards of painters and residents, and for the purpose of reducing air pollution. However, a coating film made of an aqueous coating material generally tends to adhere to contaminants as compared with a coating film made of a solvent-type coating material.

  As a technique for suppressing the adhesion of contaminants, a technique is disclosed in which an organosilicate and / or a condensate thereof (hereinafter referred to as “organosilicate etc.”) is blended in a coating material (Patent Document 1). The technology of Patent Document 1 is made by blending organosilicate or the like in a coating material, and making the coating surface hydrophilic by acid treatment after the coating is formed, making it difficult for oily contaminants to adhere, and further attaching the contaminants. It is characterized by having the performance of washing away with water droplets such as rain.

  However, generally organosilicates and the like have reactivity with water. Therefore, when the technique of Patent Document 1 is applied to an aqueous coating material, it is difficult to control hydrolysis condensation reaction such as organosilicate, the viscosity rapidly increases in a short time, and further gelation occurs. The problem of hindering the painting work and the problem that the compatibility between the aqueous resin and the organosilicate is poor and agglomerates are formed after mixing are likely to occur. In particular, in general, the glossy type water-based coating material has a drawback that the surface gloss is extremely lowered due to the poor compatibility. Furthermore, even when coating is performed immediately after mixing and a coating film is formed, there is a drawback that sufficient stain resistance cannot be obtained. In particular, in the initial stage of coating film formation, there is a problem that contaminants are more likely to adhere due to adhesiveness caused by organosilicate or the like.

WO94 / 06870 Publication WO99 / 05228

As a technique for solving the above problem, there is a technique using an alkoxysilane compound having a polyoxyalkylene group (Patent Document 2). According to this technique, the compatibility between the alkoxysilane compound and the aqueous resin is improved, and the formed coating film has relatively good gloss and also has stain resistance.
However, the alkoxysilane compound of Patent Document 2 also has an alkoxysilyl group having reactivity with water. Therefore, in order to distribute the coating material of Patent Document 2 in the market, it is necessary to use a two-component coating material in which an aqueous resin and an alkoxysilane compound are separate components and are mixed at the time of coating, and at the time of storage until coating During distribution, sufficient care must be taken not to mix moisture into the alkoxysilane compound.

The present invention has been made in view of such a problem, during storage, it is possible to reduce the effort in the distribution or the like, can exhibit excellent stain resistance in the formed coating film aqueous The object is to obtain a covering material.

As a result of intensive studies in order to solve these problems, the present inventors have conceived an aqueous coating material containing specific water-dispersible silica and a fluorine-containing compound as essential components for the synthetic resin emulsion, and the present invention. It came to complete.

That is, the present invention relates to the following aqueous coating materials.
1. Synthetic resin emulsion (A), water-dispersible silica (B) having a particle diameter of 1 to 200 nm, an aqueous coating material containing, as essential components, a fluorine-containing compound (C) having a polyfluoroalkyl group and a nonionic or amphoteric hydrophilic group The mixing ratio of the component (A), the component (B), and the component (C) is such that the solid content of the component (A) is 1% by weight to 50% by weight with respect to the total amount of the coating material. An aqueous coating material, wherein the solid content is 0.1 wt% or more and 40 wt% or less, and the component (C) is 0.01 wt% or more and 3.0 wt% or less.
2. The component (A) is an acrylic resin emulsion having a hydrolyzable silyl group. The water-based coating material described in 1.
3. Component (C) is a fluorine compound (C) having at least one functional group selected from the group consisting of a polyfluoroalkyl group, a polyalkylene oxide group, and an amine oxide group, and / or a polyfluoroalkyl group. 1. It contains a fluorine-containing compound (C) having a betaine structure as an essential component. Or 2. The water-based coating material described in 1.
4). Furthermore, it contains at least one selected from coloring pigments, extender pigments and aggregates. ~ 3. The water-based coating material according to any one of the above.
5. The pH of the component (B) is 5 or more and 12 or less. ~ 4. The water-based coating material according to any one of the above.

The aqueous coating material of the present invention exhibits excellent stain resistance in the formed coating film. The aqueous coating material of the present invention can reduce labor during storage, distribution, etc., and can also be made into a one-pack type.

  Hereinafter, the best mode for carrying out the present invention will be described.

The aqueous coating material of the present invention comprises a synthetic resin emulsion (A) (hereinafter referred to as “component (A)”), water-dispersible silica (B) having a particle diameter of 1 to 200 nm (hereinafter referred to as “component (B)”), polyfluoro A fluorine-containing compound (C) having an alkyl group and a nonionic or amphoteric hydrophilic group (hereinafter referred to as “component (C)”) is contained as an essential component.
In addition to the components (A) to (C), the aqueous coating material of the present invention can appropriately contain each component necessary as a target aqueous coating material in addition to the dispersion medium of the above components.

Of these, the component (A) acts as a binder and can be obtained by copolymerizing various polymerizable monomers. Examples of the polymerizable monomer component constituting the component (A) include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n- Amyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) (Meth) acrylic esters such as acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate;
Carboxyl group-containing monomers such as acrylic acid, methacrylic acid, crotonic acid, maleic acid or its monoalkyl ester, itaconic acid or its monoalkyl ester, fumaric acid or its monoalkyl ester;
Contains amino groups such as N-methylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminoethyl vinyl ether, N- (2-dimethylaminoethyl) acrylamide, N- (2-dimethylaminoethyl) methacrylamide monomer;
Pyridine monomers such as vinylpyridine;
Hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate;
Vinyl ester monomers such as vinyl acetate and vinyl propionate;
Nitrile group-containing monomers such as acrylonitrile and methacrylonitrile;
Aromatic monomers such as styrene, 2-methylstyrene, vinyltoluene, t-butylstyrene, chlorostyrene, vinylanisole, vinylnaphthalene, divinylbenzene;
Amide group-containing monomers such as acrylamide, methacrylamide, maleic acid amide, N-methylol (meth) acrylamide and diacetone acrylamide;
Epoxy group-containing monomers such as glycidyl (meth) acrylate, diglycidyl (meth) acrylate, and allyl glycidyl ether;
Carbonyl group-containing monomers such as acrolein, diacetone (meth) acrylamide, vinyl methyl ketone, vinyl ethyl ketone, vinyl butyl ketone;
Alkoxysilyl groups such as vinyltrimethoxysilane, vinyltriethoxysilane, γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxysilane, γ- (meth) acryloyloxypropylmethyldimethoxysilane Containing monomers;
Vinylidene halide monomers such as vinylidene chloride and vinylidene fluoride;
Other examples include ethylene, propylene, isoprene, butadiene, vinyl pyrrolidone, vinyl chloride, vinyl ether, vinyl ketone, vinyl amide, and chloroprene. These can be used alone or in combination of two or more. Among these, when an alkoxysilyl group-containing monomer is included as the polymerizable monomer, the physical properties of the coating film can be improved by interaction with the component (B).

  Although the minimum film-forming temperature of (A) component can be set suitably, it is 80 degrees C or less normally, Preferably it is about -30-50 degreeC, More preferably, it is -20-30 degreeC. When the minimum film-forming temperature of the component (A) is within such a range, it is possible to exhibit the stain resistance while ensuring the coating film properties such as crack resistance.

  Although the manufacturing method of (A) component is not specifically limited, For example, emulsion polymerization, soap free emulsion polymerization, dispersion polymerization, feed emulsion polymerization, feed dispersion polymerization, seed emulsion polymerization, seed dispersion polymerization, etc. are employable. (A) The average particle diameter of a component is about 0.05-0.3 micrometer normally. The solid content ratio in the total amount of component (A) is not particularly limited, but is usually about 10 to 60% by weight.

  In the present invention, a crosslinking reaction type synthetic resin emulsion, a core-shell type synthetic resin emulsion, and the like can also be used as the component (A). Two or more synthetic resin emulsions can be used in combination. Among these, as the crosslinking reaction in the crosslinking reaction type synthetic resin emulsion, for example, carboxyl group and metal ion, carboxyl group and carbodiimide group, carboxyl group and epoxy group, carboxyl group and aziridine group, carboxyl group and oxazoline group, hydroxyl group and isocyanate group , A combination of carbonyl group and hydrazide group, epoxy group and hydrazide group, epoxy group and amino group, hydrolyzable silyl groups, and the like. Among these, preferable crosslinking reactions include a carboxyl group and an epoxy group, a carboxyl group and an oxazoline group, a carbonyl group and a hydrazide group, and an epoxy group and a hydrazide group.

Moreover, it is preferable that (A) component can react with the (B) component mentioned later. The component (A) is preferably an emulsion having a functional group such as a hydroxyl group or a hydrolyzable silyl group that can react with the silanol group present in the component (B).
By chemically bonding the component (A) and the component (B), it becomes possible to exhibit the stain resistance while securing the coating film properties such as crack resistance.

  The component (B) in the present invention is water-dispersible silica having a particle size of 1 to 200 nm. The particles constituting the component (B) are compounds having a high hardness because of silica as a main component, and having silanol groups on the particle surfaces. Such a component (B) greatly contributes to the effect of improving the stain resistance.

  The particle size of the component (B) is usually 1 to 200 nm, preferably 5 to 100 nm, more preferably 10 to 50 nm, and still more preferably 20 to 40 nm as the primary particle size. If the particle diameter is too large, the transparency of the coating film may be impaired in the clear type coating material, and the gloss of the glossy type coating material may be insufficient. is there. When the particle size is too small, there is a possibility that a sufficient effect cannot be obtained in the stain resistance. (B) The average primary particle diameter of a component is 5-100 nm, More preferably, it is 10-50 nm, More preferably, it is 20-40 nm. In the present invention, two or more kinds of water-dispersible silica having different average primary particle sizes can be used. The particle diameter of the component (B) is a value measured by a light scattering method.

  The pH of the component (B) is usually 5 or more and 12 or less, preferably 6 or more and 10 or less, more preferably 6 or more and 9 or less. The component (B) adjusted to such a pH can exhibit hydrophilicity due to abundant silanol groups on the particle surface, and greatly contributes to an improvement in stain resistance.

  Such a component (B) can be produced using, for example, sodium silicate, lithium silicate, potassium silicate, or a silicate compound as a raw material. Among these, as silicate compounds, for example, tetramethoxysilane, tetraethoxysilane, tetra n-propoxysilane, tetraisopropoxysilane, tetra n-butoxysilane, tetraisobutoxysilane, tetrasec-butoxysilane, tetra-t-butoxy Examples thereof include silane, tetraphenoxysilane, and their condensates. In addition, alkoxysilane compounds other than the above silicate compounds, alcohols, glycols, glycol ethers, fluorine alcohols, silane coupling agents, polyoxyalkylene group-containing compounds, and the like can also be used. A catalyst etc. can also be used at the time of manufacture. Further, after the production process or after production, the metal contained in the catalyst or the like can be removed by ion exchange treatment or the like.

As the component (B), those having an electric conductivity of 3 mS / cm or less (preferably 2 mS / cm or less, more preferably 1 mS / cm or less) are suitable. In addition, the electrical conductivity said here is a value measured using "Model SC82 personal SC meter SC8221-J" (made by Yokogawa Electric Corporation) (measurement temperature 25 degreeC).
By using such a component (B), the water resistance and stain resistance of the formed coating film can be further enhanced.

  As the medium for the component (B), water and / or a water-soluble solvent can be used. Examples of the water-soluble solvent include alcohols, glycols, glycol ethers and the like. In the present invention, it is particularly desirable that the medium is composed only of water. By using such a component (B), it is possible to reduce the volatile organic solvent (low VOC) of the coating material. Moreover, the aggregate generation | occurrence | production at the time of mixing with (A) component can also be suppressed.

  The solid content of the component (B) is usually 5 to 50% by weight, preferably 10 to 40% by weight, and more preferably 15 to 30% by weight. If the solid content of the component (B) is within such a range, the stability of the component (B) itself, and the stability when the component (A) and the component (B) are mixed can be ensured. . If the solid content is too large, the component (B) itself may become unstable, or the coating material may become unstable when mixed with the component (A). If the solid content is too small, a large amount of component (B) must be mixed in order to obtain a sufficient anti-staining effect, which is not practical.

The component (C) in the present invention is a fluorine-containing compound having a polyfluoroalkyl group and a nonionic or amphoteric hydrophilic group. In the present invention, excellent contamination resistance can be exhibited by using the component (C) and the component (B) together. Furthermore, it is possible to suppress the adhesion of contaminants in the initial stage of film formation, and to improve the drying property and flexibility of the coating film.
Although the specific mechanism of action in which such an effect is exhibited is not clear, the component (B) and the component (C) are orientated on the surface of the coating film during the formation of the coating film, and the hardness of the coating film surface is due to the synergistic action of both. The hydrophilicity and the like are effectively increased, and at the same time, it is presumed that the flexibility and the film-forming property are improved by the action of the component (A) in the coating film.

  Such a polyfluoroalkyl group of component (C) is a group in which all or part of the hydrogen atoms bonded to carbon atoms in the alkyl group having a linear, branched or cyclic skeleton are substituted with fluorine atoms. is there. This polyfluoroalkyl group may have an etheric oxygen atom, a thioetheric sulfur atom or the like between carbon atoms in the polyfluoroalkyl group. The polyfluoroalkyl group may contain a halogen atom other than the fluorine atom. The number of carbon atoms in the polyfluoroalkyl group is usually 1 or more, preferably 3 or more, more preferably 6 or more. The upper limit of the number of carbon atoms in the polyfluoroalkyl group is usually 40 or less, preferably 20 or less. As the polyfluoroalkyl group of component (C), a perfluoroalkyl group is particularly suitable.

Examples of nonionic hydrophilic groups include polyalkylene oxide groups and amine oxide groups. Among these, as a polyalkylene oxide group, a polyethylene oxide group, a polypropylene oxide group, etc. are mentioned, for example, What mixed ethylene oxide group and a propylene oxide group can also be used. The repeating number of alkylene oxide is usually 2-100.
Examples of amphoteric hydrophilic groups include nitrogen-containing amphoteric hydrophilic groups such as quaternary ammonium halogen salts and betaines. Among these, examples of the halogen in the quaternary ammonium halogen salt include a chlorine atom, a bromine atom, and an iodine atom. Betaine has a quaternary ammonium and an anion of an acid, and examples of the acid include carboxylic acid. As the hydrophilic group in component (C), a nitrogen-containing amphoteric hydrophilic group having a betaine structure is particularly suitable.

As (C) component in this invention, what has the said functional group together can be used. Such a component (C) is prepared by synthesizing a polyfluoroalkyl group-containing compound as an intermediate by, for example, an electrolytic fluorination method, a telomerization method, an oligomerization method, etc., and then adding a hydrophilic group to the intermediate. It can manufacture by introducing.
As the component (C), a 0.01% aqueous solution having a surface tension at 25 ° C. of 20 mN / m or less (more preferably 18 mN / m or less) is suitable.

In addition to the above components, the aqueous coating material of the present invention includes, as other components, water, a dispersion medium such as a solvent, colored pigments, extender pigments, aggregates, film-forming aids, plasticizers, antifreezing agents, preservatives , Antifungal agents, antibacterial agents, antifoaming agents, pigment dispersants, thickeners, leveling agents, wetting agents, pH adjusters, fibers, matting agents, UV absorbers, antioxidants, light stabilizers, adsorbents , A catalyst, a crosslinking agent, a silane coupling agent, and the like can be mixed. By using such components in appropriate combinations, various forms of coating materials can be designed. The aqueous coating material of the present invention can be produced by uniformly mixing these other components as required in addition to the components (A) to (C). Processing such as pre-combination of the component (B) and the component (C) is not necessary.

The present invention can be applied to various water-based coating materials such as a clear type, a glossy type, and a matte type. Moreover, it can also be applied to water-based coating materials such as natural stone-like coating materials, thin finish coating materials, thick finish coating materials, etc. In this case, in addition to the above components (A) to (C), aggregates, constitutions What is necessary is just to mix suitably 1 or more types, such as a pigment.

As the aggregate, for example, at least one selected from natural aggregates such as natural stones and pulverized natural stones and artificial aggregates such as colored aggregates can be suitably used. Specifically, for example, marble, granite, serpentine, granite, fluorite, cryolite, feldspar, limestone, quartzite, quartz sand, crushed stone, mica, siliceous shale, and pulverized products thereof, ceramic pulverized products, ceramic pulverized products Products, crushed glass, glass beads, crushed resin, resin beads, rubber particles, metal particles, and the like. In addition, pulverized products such as shells, shells, wood, charcoal, activated carbon and the like can be used. Furthermore, those whose surfaces are colored and coated by performing surface treatment with pigments, dyes, glazes, and the like can also be used. The particle diameter of the aggregate is usually 0.05 mm or more and 5 mm or less.
Examples of extender pigments include heavy calcium carbonate, light calcium carbonate, kaolin, clay, porcelain clay, china clay, diatomaceous earth, hydrous finely divided silicic acid, talc, barite powder, barium sulfate, precipitated barium sulfate, barium carbonate, magnesium carbonate. , Silica powder, aluminum hydroxide, and the like, and one or more of these can be used. The particle size of the extender pigment is usually less than 50 μm (preferably 0.5 μm or more and 30 μm or less).

The mixing ratio of the component (A), the component (B), and the component (C) is such that the solid content of the component (A) is 1% by weight or more and 50% by weight or less (preferably 5% by weight or more 40%) with respect to the total amount of the aqueous coating material. % By weight), the solid content of the component (B) is 0.1% by weight to 40% by weight (preferably 0.2% by weight to 30% by weight), and the component (C) is 0.01% by weight. The content is 3.0% by weight or less (preferably 0.05% by weight or more and 2.0% by weight or less). With such a mixing ratio, the effects of the present invention can be sufficiently exerted.
(A) When there are too few components, it is difficult to form a coating film.
When the amount of the component (B) is too small, sufficient contamination resistance cannot be obtained. Moreover, when there are too many (B) components, it will become easy to produce a crack in a coating film. In addition, in a glossy type coating material, it is difficult to obtain a highly glossy coating film.
When the amount of the component (C) is less than the above mixing ratio, it is difficult to obtain sufficient physical properties in terms of contamination resistance. Moreover, when there are too many (C) components, there exists a possibility of affecting the external appearance of a coating film, water resistance, etc.
In particular, when the aqueous coating material is a clear type, the solid content of the component (A) is 5% to 50% by weight (preferably 8% to 40% by weight), (B ) The solid content of the component is 1% by weight to 40% by weight (preferably 3% by weight to 35% by weight, more preferably 5% by weight to 30% by weight), and the component (C) is 0.01% by weight. % To 3.0% by weight (preferably 0.05% to 2.0% by weight).
In addition, when the coating material is a glossy type, matte type, including natural pigments, extender pigments, aggregates, etc., and natural stone tone coating material, thin finish coating material, thick finish coating material, etc. The solid content of the component (A) is 1% by weight or more and 40% by weight or less (preferably 5% by weight or more and 30% by weight or less), and the solid content of the component (B) is 0.1% by weight or more with respect to the total amount of the coating material. 20 wt% or less (preferably 0.2 wt% or more and 15 wt% or less), (C) component is 0.01 wt% or more and 3.0 wt% or less (preferably 0.05 wt% or more and 2.0 wt% or less) % Or less). Further, the mixing ratio of the total amount of the color pigment, extender pigment, and aggregate is about 0.01% by weight to 90% by weight (preferably 0.1% by weight to 80% by weight) with respect to the total amount of the coating material. I just need it.

The aqueous coating material of the present invention can be applied to various base materials such as concrete, mortar, metal, plastic, slate plate, extruded plate, siding board, ALC plate, plywood, glass, and porcelain tile. In particular, it is suitable for the protection and beauty of buildings such as buildings and civil engineering structures.
At this time, the coating material of the present invention is applied to the final finished surface, and can be directly applied to the base material, or surface treatment (sealer treatment, filler treatment, surfacer using any surface treatment material). It is also possible to paint after applying treatment, putty treatment, etc.).
The coating method is not particularly limited, and it may be applied to the substrate by a method such as spray coating, roller coating, trowel coating, brush coating, etc., and may be applied only once or multiple times. When coating a plurality of times, the same or different types of coating materials may be applied a plurality of times.
For example, when the substrate or the surface treatment material layer applied to the substrate surface has elasticity including an organic material, etc., after coating a coating material having a high elongation rate, the coating material having a low elongation rate is applied in order. In addition to imparting followability to the substrate, it is possible to exhibit contamination resistance.
Specifically, a first coating material is applied to a base material having an elongation rate of 50% or more (more than 80% or more) by applying a first coating material having an elongation rate of 30% or more and 90% or less of the base material. Forming a second coating material layer by coating a second coating material that is 30% or more and 90% or less of the elongation of the first coating material layer on the first coating material layer; Thus, it is possible to impart followability to the substrate and to exhibit stain resistance.
Moreover, when the surface treatment material layer applied to the substrate or the substrate surface has elasticity including an organic material or the like, by sequentially coating the coating materials having different mixing ratios of the component (A) and the component (B), Adhesiveness and followability can be imparted to the organic substrate, and contamination resistance can be exhibited.
Specifically, a first covering material layer is formed by coating a first covering material having a content of the component (B) (solid content) of 0% by weight or more and 1% by weight or less on the base material, On the first coating material layer, the content of the component (B) is larger than that of the first coating material, and the content of the component (B) (solid content) is 0.5 wt% or more and 20 wt% or less. By coating 2 coating materials and forming a 2nd coating material layer, while providing adhesiveness and followable | trackability with respect to a base material, stain resistance can be exhibited.

The coating amount when coating the aqueous coating material of the present invention may be appropriately selected depending on the form and use of the coating material. For example, in the case of a clear type, a glossy type, a matte type, etc., 0.1 to 0.5 kg / ^{m 2} approximately, natural stone tone coating material, seeding topcoat material, in the case of such thickening topcoat material is about 0.5 to 10 / ^{m 2.} The viscosity of the coating material can be appropriately adjusted by diluting with water or the like during coating. The dilution ratio is usually about 0 to 20% by weight. Drying after coating is usually performed at room temperature, but can be appropriately heated as necessary.

Examples are given below to clarify the features of the present invention. In the examples, each aqueous coating material was manufactured using the raw materials shown below.

Emulsion A: Acrylic resin emulsion (methyl methacrylate-styrene-cyclohexyl methacrylate- (2-ethylhexyl acrylate) -methacrylic acid copolymer, pH 8.7, solid content 50% by weight, minimum film-forming temperature 18 ° C.)
Emulsion B: Acrylic resin emulsion (methyl methacrylate-styrene-2-ethylhexyl acrylate- (γ-methacryloyloxypropyltrimethoxysilane) -methacrylic acid copolymer, pH 8.9, solid content 50% by weight, minimum film-forming temperature 26 ℃)
Emulsion C: acrylic resin emulsion (methyl methacrylate-cyclohexyl methacrylate- (2-ethylhexyl acrylate)-(n-butyl methacrylate)-(n-butyl acrylate) -methacrylic acid copolymer, pH 8.9, solid content 49% by weight Minimum film-forming temperature 0 ° C)
Coloring pigment: Titanium oxide dispersion (solid content 70% by weight)
-Film-forming aid: 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate-Thickener: Polyurethane thickener-Defoamer: Silicone defoamer-Water dispersible silica A : Silica sol (pH 7.6, solid content 20% by weight, average primary particle size 27 nm, electric conductivity 0.6 mS / cm)
Water-dispersible silica B: silica sol (pH 9.3, solid content 20% by weight, average primary particle size 20 nm, electrical conductivity 1.8 mS / cm)
Fluorine-containing compound A: perfluoroalkylamine oxide (surface tension of 16.0% aqueous solution 16.0 mN / m (25 ° C.))
Fluorine-containing compound B: perfluoroalkyl ethylene oxide adduct (0.01% aqueous solution surface tension 17.5 mN / m (25 ° C.))
Fluorine-containing compound C: perfluoroalkylbetaine (0.01% aqueous solution surface tension of 16.0 mN / m (25 ° C.))
Fluorine-containing compound D: perfluoroalkyltrimethylammonium salt (surface tension of 17.0% aqueous solution 17.0 mN / m (25 ° C.))
-Fluorine-containing compound E: trifluoroethanol-Aggregate: Colored aggregate mixture with a particle size of 120-300 μm

[1] Test Example 1 (Examples 1 to 9, Comparative Examples 1 to 5)
<Manufacture of coating material>
According to the formulation shown in Table 1, each raw material was uniformly mixed by a conventional method to produce a coating material. The compounding amounts in Table 1 are expressed in parts by weight.

<Test method>
(1) Storage stability Viscosity was measured immediately after the coating material was produced. Next, the covering material was put in a container, sealed, stored for 15 days in an atmosphere at 50 ° C., and then the viscosity was measured again.

The viscosity change by the above operation was investigated. The evaluation criteria are as follows. The viscosity was measured using a BH viscometer in a standard state (temperature 23 ° C., relative humidity 50%).
○: Change in viscosity less than 10% Δ: Change in viscosity from 10% to less than 50% ×: Change in viscosity from 50% or more

(2) After applying a coating material using a film applicator with a clearance of 150 μm to a transparent glass plate having a specular gloss of 150 × 120 × 3 mm and placing the glass plate horizontally and drying and curing in a standard state for 48 hours , Specular gloss was measured according to JIS K 5600-4-7. The measurement angle was 60 degrees.

(3) Contact angle 150 mm × 75 mm × 3 mm slate plate was coated with an epoxy-based primer to a dry film thickness of 30 μm and dried in standard conditions for 8 hours. A test specimen was prepared by coating to 40 μm and drying in a standard state for 7 days.
The contact angle of the coating surface of the test specimen obtained by the above method was measured. The contact angle was measured with a CA-A type contact angle measuring device manufactured by Kyowa Interface Science Co., Ltd.

(4) Rain-strip stain resistance A 300 × 150 × 3 mm aluminum plate bent at a position one third from the upper end so that the inner angle is 135 degrees was used as a test substrate. On the convex surface of this test substrate, an epoxy-based primer was spray-coated so that the dry film thickness was 30 μm, and dried in a standard state for 8 hours. Next, the coating material was spray-coated so that the dry film thickness was 40 μm, and was dried and cured in a standard state for 7 days.
The specimen obtained by the above method was placed facing south on Ibaraki City, Osaka, with the wide area vertical, and exposed outdoors for 3 months. At this time, the rain streak stain state on the vertical surface was visually observed and evaluated in 10 stages (excellent: 10> 1: poor) depending on the degree of the stain.

<Test results>
The test results are shown in Table 2. In Examples 1 to 9, good results could be obtained in any test.

[2] Test Example 2 (Examples 10 to 15, Comparative Examples 6 to 9)
<Manufacture of coating material>
According to the formulation shown in Table 3, each raw material was uniformly mixed by a conventional method to produce a coating material. The blending amounts in Table 3 are expressed in parts by weight.

<Test method>
(1) Rain-strip stain resistance A 300 × 150 × 3 mm aluminum plate bent at a position one third from the upper end so that the inner angle is 135 degrees was used as a test substrate. On the convex surface of this test substrate, an epoxy-based primer was spray-coated so that the dry film thickness was 30 μm, and dried in a standard state for 8 hours. Next, the coating material was spray-coated so that the dry film thickness was about 2 mm, and was dried and cured in a standard state for 7 days.
The specimen obtained by the above method was placed facing south on Ibaraki City, Osaka, with the wide area vertical, and exposed outdoors for 3 months. At this time, the rain streak stain state on the vertical surface was visually observed and evaluated in 10 stages (excellent: 10> 1: poor) depending on the degree of the stain.

<Test results>
The test results are shown in Table 3. In Examples 10 to 14, good results could be obtained.

  In addition, about Example 15, it spray-coats so that the dry film thickness may be set to about 0.1 mm on the test body of the comparative example 6 obtained by said method so that the dry film thickness may be set to about 0.1 mm, The test piece was dried and cured for 7 days in the standard state, and the above-mentioned rain-strip stain resistance test was conducted. The test results are shown in Table 3. In Example 15, good results could be obtained.

[3] Test example 3
<Manufacture of coating material>
Emulsion A 200 parts by weight, film-forming aid 18 parts by weight, thickener 3 parts by weight, antifoaming agent 0.3 part by weight, water-dispersible silica A 13 parts by weight, and fluorine-containing compound C 2 parts by weight are uniformly mixed by a conventional method. Thus, a covering material 3-1 was produced.
Moreover, what mixed emulsion A200 weight part, film forming adjuvant 18 weight part, thickener 3 weight part, antifoamer 0.3 weight part, and water dispersible silica A13 weight part was used as coating | covering material 3-2. . A mixture of 200 parts by weight of emulsion A, 18 parts by weight of a film-forming aid, 3 parts by weight of a thickener, 0.3 parts by weight of an antifoaming agent and 2 parts by weight of a fluorine-containing compound C was used as a coating material 3-3.

<Test methods and test results>
The coating materials 3-1 to 3-3 were each applied to an aluminum plate with a thickness of 1 mm, and then left in a 5 ° C. environment. About this test body, the weight reduction rate of the coating film after 72 hours and 168 hours was measured.
As a result, the coating material 3-1 had a weight loss rate of 20% by weight and 42% by weight after 72 hours and 168 hours, respectively. On the other hand, the covering material 3-2 was 11% by weight (after 72 hours), 27% by weight (after 168 hours), and the covering material 3-3 was 11% by weight (after 72 hours), 25% by weight (after 168 hours). )Met. The covering material 3-1 was excellent in drying property compared with the covering materials 3-2 and 3-3.

[4] Test example 4
<Manufacture of coating material>
Emulsion A 200 parts by weight, film-forming aid 18 parts by weight, thickener 5 parts by weight, antifoaming agent 1 part by weight, and aggregate 450 parts by weight were uniformly mixed by a conventional method to produce a covering material 4-1. .
In addition, 200 parts by weight of emulsion A, 18 parts by weight of film-forming aid, 5 parts by weight of thickener, 1 part by weight of defoaming agent, 10 parts by weight of water-dispersible silica A, 2 parts by weight of fluorine-containing compound C, 450 parts by weight of aggregate By uniformly mixing by a conventional method, a coating material 4-2 was produced.
Emulsion A 200 parts by weight, film-forming aid 18 parts by weight, thickener 5 parts by weight, antifoaming agent 1 part by weight, fluorine-containing compound C 2 parts by weight, and aggregate 450 parts by weight are uniformly mixed and coated. Material 4-3 was produced.
150 parts by weight of emulsion A, 50 parts by weight of emulsion B, 18 parts by weight of film-forming aid, 5 parts by weight of thickener, 1 part by weight of defoaming agent, 10 parts by weight of water-dispersible silica A, 2 parts by weight of fluorine-containing compound C, 450 of aggregate Weight parts were uniformly mixed by a conventional method to produce a covering material 4-4.

<Test method>
(Followability test 1)
Using a modified silicone sealant, two siding boards (300 mm × 170 mm × 12 mm) were joined together with a gap of 10 mm to prepare a substrate.
On this base material, the coating material 4-1 was spray-coated so that the coating amount was 1.0 kg / m ² and dried at a temperature of 23 ° C. and a humidity of 50%.
Next, 2 hours after the coating, the coating material 4-2 was spray-coated so that the coating amount was 2.0 kg / m ² and dried at a temperature of 23 ° C. and a humidity of 50% for 24 hours. Obtained.
Evaluation was performed according to the surface condition when the produced specimen was displaced by 30% in the horizontal direction with a tensile tester. As a result, no abnormality was observed in the specimen.
(Followability test 2)
The test was performed in the same manner as the follow-up test 1 except that the covering material 4-1 was replaced with the covering material 4-3 and the covering material 4-2 was replaced with the covering material 4-4. As a result, no abnormality was observed in the specimen.
(Followability test 3)
Using a modified silicone sealant, two siding boards (300 mm × 170 mm × 12 mm) were joined together with a gap of 10 mm to prepare a substrate.
On the base material, the coating material 4-2 was spray-coated so that the coating amount was 2.0 kg / m ² and dried at a temperature of 23 ° C. and a humidity of 50% to obtain a test specimen.
Evaluation was performed according to the surface condition when the produced specimen was displaced by 30% in the horizontal direction with a tensile tester. As a result, almost no abnormality was observed in the test specimen.

Claims (5)

Synthetic resin emulsion (A), water-dispersible silica (B) having a particle diameter of 1 to 200 nm, an aqueous coating material containing, as essential components, a fluorine-containing compound (C) having a polyfluoroalkyl group and a nonionic or amphoteric hydrophilic group The mixing ratio of the component (A), the component (B), and the component (C) is such that the solid content of the component (A) is 1% by weight to 50% by weight with respect to the total amount of the coating material. An aqueous coating material, wherein the solid content is 0.1 wt% or more and 40 wt% or less, and the component (C) is 0.01 wt% or more and 3.0 wt% or less.
The aqueous coating material according to claim 1, wherein the component (A) is an acrylic resin emulsion having a hydrolyzable silyl group.
Component (C) is a fluorine compound (C) having at least one functional group selected from the group consisting of a polyfluoroalkyl group, a polyalkylene oxide group, and an amine oxide group, and / or a polyfluoroalkyl group. The aqueous coating material according to claim 1, comprising a fluorine-containing compound (C) having a betaine structure as an essential component .
The aqueous coating material according to any one of claims 1 to 3, further comprising at least one selected from a color pigment, an extender pigment, and an aggregate.
(B) pH of a component is 5-12, The aqueous coating material in any one of Claims 1-4 characterized by the above-mentioned.