JPWO2020184722A1 - Water-based paint compositions, paint films and painted articles - Google Patents

Abstract

The present invention relates to a water-based coating composition having excellent water resistance even when an odorless neutralizing agent or a neutralizing agent that does not easily cause odor is used, and more specifically, a structural unit derived from a reactive emulsifying agent is used. The acrylic resin contains an acrylic resin and a neutralizing agent selected from the group consisting of an alkaline inorganic compound excluding ammonia and an alkaline organic compound having a boiling point of more than 260 ° C., and the acrylic resin is dispersed in an aqueous coating composition in the form of an emulsion. It relates to a water-based paint composition characterized by the fact that it is used.

Description

The present invention relates to a water-based coating composition, a coating film obtained from the water-based coating composition, and a coated article having the coating film, and in particular, an odorless neutralizing agent or a neutralizing agent that is unlikely to cause odor is used. It relates to a water-based coating composition having excellent water resistance even in some cases.

In recent years, in interior and exterior building paints, especially indoor paints, there has been a demand for conversion from solvent-based paints to water-based paints from the viewpoints of air pollution problems, odors, safety, etc., and nowadays, water-based emulsions are used as binders in most applications. Water-based paints occupy the mainstream. However, a small amount of volatile organic compounds (VOCs) contained in water-based paints still remain as a problem of odor, and further reduction thereof has been strongly demanded.

In water-based emulsions and paints using them, even if the amount of residual monomers is very small, the odor derived from acrylic monomers is a problem, and its reduction has been strongly requested. Further, a small amount of an acidic group-containing polymerizable unsaturated monomer such as a carboxylic acid is copolymerized in the emulsion as a component for ensuring the coating workability and stability of the paint and the adhesive force to the object to be coated. Conventionally, various amines and volatile alkalis such as ammonia, which are not contained in VOC, have been used as the neutralizing agent, and their odors have become a problem, and their reduction has been strongly requested.
Japanese Patent Application Laid-Open No. 2003-321642 (Patent Document 1) describes a water-based paint having a significantly reduced VOC content, a low odor, and excellent properties such as low-temperature film-forming property, surface non-adhesiveness, and low-temperature stability. The resin composition is disclosed, the residual monomer content is less than 100% by weight of the whole, no organic solvent having a boiling point of 260 ° C. or lower is used, and alkali metal hydroxides such as sodium hydroxide are used from the viewpoint of odor. It is stated that it is preferable to add it as a basic compound.

Further, as a method of reducing odor, a method of blending a porous material in a paint is known. For example, Japanese Patent Application Laid-Open No. 2018-2928 (Patent Document 2) is a coating composition containing a resin emulsion composition (a) and an inorganic porous pigment (b) made of zeolite, which is contained in the zeolite. Described is a coating composition having a silica / alumina (mol / mol) ratio of 15 or more and a content of the zeolite in an amount of 0.1 to 500 parts by mass based on 100 parts by mass of the solid content of the resin emulsion composition (a). However, it is said that this makes it possible to provide a coating composition having a higher effect of suppressing the odor generated by the coating composition itself than in the past.

Japanese Unexamined Patent Publication No. 2003-321642 JP-A-2018-2928

According to the coating composition described in Patent Document 2, the generation of odor is suppressed by retaining the component causing the odor (odor component) in the specific zeolite, but it is contained in the coating composition. The odorous components are not sufficiently removed.

For this reason, avoiding the use of the odorous component itself seems to be the most reliable solution, but as described in Patent Document 1, for example, instead of ammonia as a neutralizing agent used in the preparation of emulsions. When sodium hydroxide or the like is used, there is a problem that the water resistance is lowered.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art and to provide a water-based coating composition having excellent water resistance even when an odorless neutralizing agent or a neutralizing agent that does not easily cause odor is used. There is. Another object of the present invention is to provide a coating film obtained from the water-based coating composition and a coated article having the coating film.

As a result of diligent studies to achieve the above object, the present inventor used an alkaline inorganic compound excluding ammonia or an alkaline organic compound having a boiling point of more than 260 ° C. as a neutralizing agent in order to avoid the use of odorous components. In the above, it has been found that by further using a reactive emulsifier as a part of the raw material of the acrylic resin, the decrease in water resistance that may occur due to the use of the neutralizing agent can be suppressed, and the present invention has been completed.

That is, the water-based coating composition of the present invention is neutralized selected from the group consisting of an acrylic resin containing a structural unit derived from a reactive emulsifying agent, an alkaline inorganic compound excluding ammonia, and an alkaline organic compound having a boiling point of more than 260 ° C. The acrylic resin contains an agent and is characterized in that it is dispersed in an aqueous coating composition in the form of an emulsion.

In a preferred example of the water-based coating composition of the present invention, the reactive emulsifier is a nonionic reactive emulsifier.

In another preferred example of the water-based coating composition of the present invention, the reactive emulsifier has a polyalkylene glycol chain.

In another preferred example of the water-based coating composition of the present invention, the neutralizing agent is sodium hydroxide.

In another preferred example of the water-based coating composition of the present invention, the acrylic resin has a volume average particle diameter of 30 to 300 nm.

In another preferred example of the water-based coating composition of the present invention, the acrylic resin has a glass transition temperature of 0 ° C. or lower.

Another preferred example of the water-based coating composition of the present invention is a room temperature dry water-based coating composition.

In another preferred example of the water-based coating composition of the present invention, in a test according to JIS K5663: 2008 "7.6 Low Temperature Stability Test" (however, the temperature of the low temperature incubator is maintained at -7 ° C.). The ratio of the viscosity (A) of the paint before the test to the viscosity (B) of the paint after the test: (B) / (A) is 0.99 to 1.20.

In another preferred example of the water-based coating composition of the present invention, the ammonia concentration measured by the method for measuring the ammonia concentration shown below is 12 parts by volume ppm or less.
<Measurement method of ammonia concentration>
A 3 L polyvinyl fluoride sampling bag is filled with 3 L of odorless air, 20 g of the coating composition is injected into the sampling bag, and the sampling bag is sealed. Then, after allowing it to stand at 23 ° C. for 30 minutes, the ammonia concentration in the sampling bag is measured using an ammonia gas detector tube.

In another preferred example of the water-based coating composition of the present invention, at least one of the following conditions 1 and 2 is tested for the antiviral activity value (pfu) obtained by the method for measuring the antiviral activity value shown below. The antiviral activity value at the time of this is 2.0 or more.
<Measurement method of antiviral activity value>
The virus infectivity titer is measured in the following steps in accordance with the method described in JIS R 1756: 2020 "Fine Ceramics-Antiviral Test Method for Visible Light Responsive Photocatalytic Material-Method Using Escherichia Qβ".
1. 1. One side of an acrylic plate (50 mm × 50 mm, thickness: 1 mm) is coated with a coating composition so as to have a dry film thickness of 30 μm, and a coating film is formed to prepare a test piece.
2. Place a sterilized humidity control filter paper on the bottom of the sterilized storage dish, add 5 mL of sterilized water, and then place a glass rod on the humidity control filter paper to prevent the humidity control filter paper from touching the test piece. Place the test piece on the glass rod. At that time, the test piece is installed so that the surface on which the coating film is formed faces up.
3. 3. 0.1 mL of the virus solution is dropped from the top of the test piece, and the virus solution on the test piece is coated with a polypropylene film. Then, a moisturizing glass (borosilicate glass) is placed on the top of the storage dish.
4. The test product prepared in step 3 is tested under the following condition 1 or condition 2.
・ Condition 1: Store in a dark box for 4 hours.
-Condition 2: Irradiate with a white fluorescent lamp (illuminance: 500 lp) for 4 hours.
5. After performing the test of condition 1 or condition 2 in step 4, the virus on the test piece is washed out with SCDLP medium and collected, and the virus infectivity titer (pfu) is measured.
Using the virus infectivity titer measured in step 5, the antiviral activity value (pfu) is calculated from the following formula.
Antiviral activity value (pfu) = Log (A × B) -Log (C)
However,
A: Virus solution concentration (pfu / mL)
B: Amount of virus solution dropped onto the test piece (mL)
C: Virus infectivity titer (pfu) after the test of condition 1 or condition 2.

Further, the coating film of the present invention is a coating film obtained from the above-mentioned water-based coating composition.

Further, the coated article of the present invention is a coated article having a coating film obtained from the above-mentioned water-based coating composition on the surface of the base material.

According to the present invention, a water-based coating composition having excellent water resistance even when an odorless neutralizing agent or a neutralizing agent that does not easily cause odor is used, a coating film obtained from the water-based coating composition, and the like. A coated article having a coating film can be provided.

Hereinafter, the water-based coating composition of the present invention (hereinafter, also simply referred to as the coating composition of the present invention) will be described in detail. The coating composition of the present invention comprises an acrylic resin containing a structural unit derived from a reactive emulsifying agent, and a neutralizing agent selected from the group consisting of an alkaline inorganic compound excluding ammonia and an alkaline organic compound having a boiling point of more than 260 ° C. The acrylic resin is characterized in that it is dispersed in an aqueous coating composition in the form of an emulsion.

The coating composition of the present invention contains an acrylic resin containing a structural unit derived from a reactive emulsifier. By including the reactive emulsifier as a constituent unit, elution of the emulsifier from the coating film obtained from the coating composition can be suppressed, and water resistance can be improved.
Further, by including the reactive emulsifier as a constituent unit, the low temperature stability can also be improved. Therefore, for example, as specified in "7.6 Low temperature stability test" of JIS K5663: 2008, even when the paint is repeatedly frozen and thawed, the thawed paint has the original properties. It is possible to return to.

In the present specification, the acrylic resin is a polymer of acrylic acid esters or methacrylic acid esters, and is one or more of acrylic components selected from, for example, acrylic acid, methacrylic acid and esters, amides and nitriles thereof. Examples thereof include polymers obtained by polymerizing seeds, and further include polymers obtained by polymerizing an acrylic component and a non-acrylic component such as styrene. In the coating composition of the present invention, the reactive emulsifier constituting the acrylic resin may be an acrylic component or a non-acrylic component.

Examples of the acrylic component include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, sec-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, and octyl acrylate. , Nonyl acrylate, decyl acrylate, dodecyl acrylate, n-amyl acrylate, isoamyl acrylate, lauryl acrylate, stearyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate. , T-butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, dodecyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, lauryl methacrylate, stearyl methacrylate, cyclohexyl (meth) acrylate, phenyl (meth) (Meta) acrylate-based monomers such as acrylate, benzyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, methoxypropyl (meth) acrylate, ethoxypropyl (meth) acrylate, and 2-hydroxy Ethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl acrylate, 2-aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 3-amino Examples thereof include functional group-containing monomers such as propyl (meth) acrylate, 2-butylaminoethyl (meth) acrylate, glycidyl (meth) acrylate, and allyl glycidyl ether. In addition, acrylic acid and methacrylic acid; amide-based monomers such as acrylate amide and methacrylic acid amide; γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth) acryloxipropyltriethoxysilane, β- (meth). Acryloxyethyltrimethoxysilane, β- (meth) acryloxyethyltriethoxysilane, γ- (meth) acryloxipropylmethyldimethoxysilane, γ- (meth) acryloxipropylmethyldiethoxysilane, γ- (meth) acry An alkoxysilyl group-containing single such as loxypropylmethyldipropoxysilane, γ- (meth) acryloxibutylphenyldimethoxysilane, γ- (meth) acryloxipropyldimethylmethoxysilane, and γ- (meth) acryloxipropyldiethylmethoxysilane. Quantities and the like are also included in the acrylic component.
The ratio of the acrylic component to the unit constituting the acrylic resin can be exemplified in the range of 40 to 100% by mass.

Examples of the non-acrylic component include carboxyl group-containing monomers such as fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, crotonic acid, and vinyl versatic acid; styrene, methylstyrene, chlorostyrene, and methoxy. Aromatic monomers such as styrene and vinyl toluene; Olefin monomers such as ethylene and propylene; Vinyl monomers such as vinyl acetate and vinyl chloride; Amide monomers such as maleic anhydride; Vinyl trimethoxysilane, vinyl triethoxysilane, An alkoxysilyl group-containing monomer such as vinylmethyldimethoxysilane and vinylmethyldiethoxysilane; dialkylfumarate, allylalcohol, vinylpyridine, butadiene and the like can be mentioned.

In the coating composition of the present invention, the acrylic resin contains a reactive emulsifier as a constituent unit. Here, the emulsifier is generally used to facilitate the formation of an emulsion or to promote the stability of the emulsion, but in the case of a reactive emulsifier, the emulsifier is used. Since it is incorporated as a constituent unit of the polymer as a monomer during polymerization, it is preferable from the viewpoint of suppressing the bleed-out of the emulsifier in addition to the above-mentioned effects of improving water resistance and low temperature stability. The above-mentioned reactive emulsifier is preferably an anionic or nonionic reactive emulsifier, and more preferably a nonionic reactive emulsifier.

In the coating composition of the present invention, the reactive emulsifier preferably has a polyalkylene glycol chain from the viewpoint of stability of the emulsion. Examples of the polyalkylene glycol chain include a polyethylene glycol chain and a polypropylene glycol chain. The reactive emulsifier preferably has a molecular weight in the range of 200 to 3500 from the viewpoint of water resistance and stability of the emulsion.

In the coating composition of the present invention, examples of the reactive emulsifier constituting the acrylic resin include emulsifiers having a polymerizable unsaturated bond such as a vinyl group in the molecule. Such a reactive emulsifier not only has an emulsifying function, but is also a polymerizable monomer having a polymerizable unsaturated bond such as a vinyl group in the molecule and a hydrophilic group. While ordinary emulsifiers only adsorb to the surface of the produced particles, reactive emulsifiers are (meth) as a component of the (meth) copolymer in the polymerization process of the (meth) acrylic copolymer, although not all. Since it may be incorporated into an acrylic copolymer, it has a characteristic that the emulsifier does not liberate from the polymer or is difficult to liberate due to an external factor such as water vapor after the coating film is formed.

Examples of the reactive emulsifier include an anionic reactive emulsifier and a nonionic reactive emulsifier.
Examples of the anionic reactive emulsifier include alkyl ether types (commercially available products include Aqualon KH-05 and KH-10 manufactured by Daiichi Kogyo Seiyaku Co., Ltd., and ADEKA CORPORATION SR-10 and SR. -1025, SR-20, R-3025, Latemuru PD-104 manufactured by Kao Corporation, etc.), sulfokosuccinate type (commercially available products include, for example, Latemuru S-120, S-120A, S manufactured by Kao Corporation. -180P, S-180A, Eleminor JS-20 manufactured by Sanyo Kasei Co., Ltd.), alkylphenyl ether type or alkylphenyl ester type (commercially available, for example, Aqualon HS-10 manufactured by Daiichi Kogyo Seiyaku Co., Ltd., HS-1025, AR-10, AR-1025, AR-20, AR-2020, BC-10, BC-1025, BC-20, BC-2020, ADEKA Corporation Adecaria Soap SE-10N, SE- (1025A, etc.), (meth) acrylate sulfate ester type (commercially available products include, for example, Antox MS-60, SAD, MS-2N manufactured by Nippon Emulsifier Co., Ltd., Eleminor RS-3000 manufactured by Sanyo Kasei Kogyo Co., Ltd.) , Phosphate ester type (commercially available products include, for example, H-3330PL manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., ADEKA CORPORATION PP-70, etc.).
Examples of the nonionic reactive emulsifier include alkyl ether types (commercially available products include Aqualon KN-10, KN-20, KN-30, KN-5065 manufactured by Daiichi Kogyo Seiyaku Co., Ltd., and ADEKA Corporation. ADEKA CORPORATION ER-10, ER-20, ER-30, ER-40, Latemul PD-420, PD-430, PD-450, etc. manufactured by Kao Corporation), alkylphenyl ether type or alkylphenyl ester type (commercially available) Examples of the products include Aqualon RN-10, RN-20, RN-30, RN-50, AN-10, AN-20, AN-30, AN-5065, and ADEKA Corporation manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. Adeka rear soap NE-10, NE-20, NE-30, etc.), (meth) acrylate ester type (commercially available products, for example, MA-50A, MA-100A, MPG-130MA manufactured by Nippon Emulsifier Co., Ltd. , Blemmer PE-90, PP-1000, 50PEP-300, AE-200, AP-400, etc. manufactured by Nichiyu Co., Ltd.), but the present invention is not limited to these examples.

In the coating composition of the present invention, the ratio of the reactive emulsifier to the unit constituting the acrylic resin is preferably in the range of 0.1 to 10% by mass. The above-mentioned reactive emulsifier may be used alone or in combination of two or more.

In the coating composition of the present invention, it is preferable that the acrylic resin further contains an acidic group-containing monomer as a constituent unit. By including the acidic group-containing monomer as a constituent unit, the adhesiveness to the substrate can be improved.
Examples of the acidic group-containing monomer include acrylic acid, ethylacrylic acid, propylacrylic acid, isopropylacrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, crotonic acid, and vinyl versatic. Examples thereof include carboxyl group-containing monomers such as acids and sulfonic acid group-containing monomers such as t-butylacrylamide sulfonic acid.
In the coating composition of the present invention, the ratio of the acidic group-containing monomer to the unit constituting the acrylic resin is preferably in the range of 0.1 to 15% by mass. The acidic group-containing monomer may be used alone or in combination of two or more.

In the coating composition of the present invention, the acrylic resin is dispersed in the coating composition in the form of an emulsion. Therefore, when preparing the coating composition of the present invention, it is preferable to use an acrylic resin emulsion. The acrylic resin emulsion means an emulsion in which the acrylic resin is stably dispersed in water, and if necessary, an additive such as a non-reactive emulsifier is included. A paint in which the resin is dispersed in the form of an emulsion is also referred to as an emulsion paint.

In the coating composition of the present invention, the acrylic resin emulsion can be prepared, for example, by carrying out emulsion polymerization in water using water as a medium. More preferably, an acrylic resin emulsion having a uniform structure obtained by emulsion polymerization, an acrylic resin emulsion having a heterogeneous structure obtained by a multi-step emulsion polymerization method, and the like can be mentioned, and both of these may be used together. Alternatively, the acrylic resin emulsion can be prepared as follows. For example, it may be prepared by emulsifying the acrylic resin in water while applying a forced shearing force by using a high-speed stirrer or the like. An acrylic resin emulsion can be prepared by performing phase conversion into water for an acrylic resin polymerized in an organic solvent medium, and if necessary, the organic solvent contained in the acrylic resin emulsion can be removed by distillation or the like. You may.

In the present invention, a reactive emulsifier is used for preparing the acrylic resin emulsion, but a non-reactive emulsifier may be used in combination if necessary. The mass ratio of the reactive emulsifier / non-reactive emulsifier is preferably 20/80 to 100/0, more preferably 65/35 to 100/0.
Examples of the non-reactive emulsifier include fatty acid salts such as sodium lauryl sulfate, higher alcohol sulfates, alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate, polyoxyethylene alkyl ether sulfates, and polyoxynonylphenyl ether sulfates. Anionic surfactants such as ammonium acid, polyoxyethylene styrene phenyl ether ammonium sulfate, polyoxyethylene-polyoxypropylene glycol ether sulfate; polyoxyethylene alkyl ether, polyoxyethylene nonylphenyl ether, sorbitan fatty acid ester, Nonionic surfactants such as polyoxyethylene fatty acid ester and polyoxyethylene-polyoxypropylene block copolymer; cationic surfactants such as alkylamine salts and quaternary ammonium salts can be mentioned.

In the coating composition of the present invention, the acrylic resin emulsion preferably has a pH of 7 to 10. For example, the pH of the acrylic resin emulsion can be adjusted within the above-specified range by using a neutralizing agent. If the pH of the acrylic resin emulsion is less than 7, various stability such as stability during storage and mechanical stability of the paint may be lowered, while if it exceeds 10, drying may be delayed. The neutralizing agent that can be used here is preferably a neutralizing agent selected from the group consisting of an alkaline inorganic compound excluding ammonia and an alkaline organic compound having a boiling point of more than 260 ° C., as described later.

In the acrylic resin emulsion, the acrylic component and the non-acrylic component used as the raw material of the acrylic resin may remain without being polymerized. In addition, the raw material of the acrylic resin emulsion may contain ammonia or a VOC compound. It is preferable to remove the unreacted monomer, ammonia, and VOC compound remaining in this manner from the viewpoint of suppressing the generation of odor. Therefore, it is preferable to remove them under reduced pressure during or after the preparation of the acrylic resin emulsion.

In the coating composition of the present invention, the acrylic resin preferably has a glass transition temperature of 0 ° C. or lower, more preferably -100 to 0 ° C., and even more preferably -50 to 0 ° C. By adjusting the glass transition temperature of the acrylic resin to 0 ° C. or lower, the film forming property at a low temperature can be improved.

In the present invention, the glass transition temperature (Tg) is calculated by using the following FOX formula.
1 / Tg = W1 / Tg1 + W2 / Tg2 + ... + Wi / Tgi + ... + Wn / Tgn
In the above FOX equation, Tg is the glass transition temperature (K) of the polymer composed of n kinds of monomers, and Tg (1, 2, i, n) is the glass transition temperature (K) of the homopolymer of each monomer. Yes, W (1, 2, i, n) is the mass fraction of each monomer, and W1 + W2 + ... + Wi + ... + Wn = 1.

In the coating composition of the present invention, the acrylic resin preferably has a volume average particle diameter of 30 to 300 nm, and more preferably 60 to 300 nm. By adjusting the volume average particle size of the acrylic resin dispersed in the coating composition of the present invention to 30 to 300 nm, the film forming property and the low temperature stability can be improved. In the present invention, the volume average particle size refers to a 50% particle size (D ₅₀ ) of the volume reference particle size distribution, and is a particle size distribution measured using a particle size distribution measuring device (for example, a laser diffraction / scattering type particle size distribution measuring device). Can be obtained from. The particle size in the present invention is represented by a sphere-equivalent diameter obtained by a laser diffraction / scattering method.

The coating composition of the present invention contains a neutralizing agent selected from the group consisting of alkaline inorganic compounds excluding ammonia and alkaline organic compounds having a boiling point of more than 260 ° C. The alkaline inorganic compound that can be used as a neutralizing agent is odorless or has a low odor except for ammonia, and is therefore suitable from the viewpoint of suppressing the generation of odor in the coating composition. Further, as for the alkaline organic compound that can be used as a neutralizing agent, if the boiling point exceeds 260 ° C., it usually does not evaporate at the time of painting and remains in the coating film. It is suitable from the viewpoint of suppressing the occurrence. The boiling point is the boiling point at 1 atm.

In the coating composition of the present invention, examples of the alkaline inorganic compound that can be used as a neutralizing agent include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal hydrogen carbonates such as sodium hydrogen carbonate, and carbonic acid. Alkali metal carbonates such as sodium can be exemplified, and sodium hydroxide is preferable.

In the coating composition of the present invention, the alkaline organic compound that can be used as a neutralizing agent is, for example, an amine compound, specifically, an amine compound capable of forming an ion pair with an acid group. Here, specific examples of the amine compound having a boiling point of more than 260 ° C. include triethanolamine, diethanolamine, N-butyldiethanolamine and the like.

In the coating composition of the present invention, the content of the neutralizing agent is not particularly limited, but the neutralizing agent may be used so that the pH of the acrylic resin emulsion or the coating composition described above is 7 to 10. preferable. It is preferable that a part or all of the neutralizing agent contained in the coating composition of the present invention is contained in the acrylic resin emulsion. The neutralizing agent may be used alone or in combination of two or more.

In the coating composition of the present invention, the total content of the acrylic resin and the neutralizing agent in the non-volatile content is preferably 15 to 100% by mass.

The coating composition of the present invention may contain a coloring pigment. The coloring pigment is not particularly limited, and a pigment usually used in the coating industry can be used. Specific examples include titanium dioxide, iron oxide, carbon black and the like. Further, in the coating composition of the present invention, the content of the coloring pigment in the non-volatile content is preferably 1 to 80% by mass, more preferably 20 to 75% by mass. The coloring pigment may be used alone or in combination of two or more.

The coating composition of the present invention may contain an extender pigment. Examples of the extender pigment include silica, talc, mica, calcium carbonate, barium sulfate and the like. In addition, when blending an extender pigment, it is preferable to use kaolin, silica, or calcium carbonate. Kaolin, silica and calcium carbonate are low odor extender pigments. In the coating composition of the present invention, the content of the extender pigment in the non-volatile content is preferably 1 to 65% by mass. The extender pigment may be used alone or in combination of two or more.

The coating composition of the present invention may contain an antifoaming agent. As the defoaming agent, commercially available ones can be used as appropriate, but it is preferable to use one having less odor. Defoamers are generally classified into mineral oils, silicones, polyethers, etc. according to carrier oils, and usually contain nucleating agents such as hydrophobic silica, wax, amide, and metal soap as constituents in addition to carriers. .. The content of the defoaming agent in the coating composition of the present invention is preferably 0.01 to 5% by mass. The defoaming agent may be used alone or in combination of two or more.

The coating composition of the present invention may contain an antibacterial agent or an antiviral agent, and may contain both an antibacterial agent and an antiviral agent. In addition, some antibacterial agents can impart an antiviral function, and some antiviral agents can impart an antibacterial function. An agent capable of imparting both an antibacterial function and an antiviral function in this way can also be referred to as an antibacterial / antiviral agent. Examples of antibacterial agents and antiviral agents include fine particles in which metal ions are carried on inorganic substances (porous materials such as zeolite, photocatalyst particles such as titanium oxide, phosphate minerals such as apatite, metal phosphate, etc.). Metal / inorganic oxide composite particles, organic or inorganic acids, metal iodide, metal salts (eg, salts of silver, copper, zinc, tungsten or molybdenum), silver particles, copper particles, cuprous oxide particles, fourth Examples thereof include grade ammonium salts, pyrithion compounds, sulfonic acid group-containing polymers, amino group-containing polyvinyl alcohols, organic nitrogen bromine compounds, and H-type carboxyl group-containing polymers. In particular, materials containing copper elements and H-type carboxyl groups are contained. Polymers are preferred. The content of the antibacterial agent or antiviral agent in the coating composition of the present invention is preferably 0.1 to 5% by mass, and the content of the antibacterial agent or antiviral agent in the non-volatile content in the coating composition of the present invention. The content is preferably 0.2 to 8% by mass. By adding an antibacterial agent or an antiviral agent at a ratio of 0.1 to 5% by mass with respect to the coating composition or 0.2 to 8% by mass with respect to the non-volatile content, the antibacterial function or the antiviral function is provided. Can be granted. The antibacterial agent or antiviral agent may be used alone or in combination of two or more.

The non-volatile content in the coating composition of the present invention is preferably 30 to 80% by mass. In the present specification, the non-volatile component refers to a component excluding a volatile component such as a solvent, and is a component that finally forms a coating film. In the present invention, the coating composition is heated at 130 ° C. The components remaining after drying for 60 minutes are treated as non-volatile components.

The coating composition of the present invention is a water-based coating material, and the water-based coating material is a coating material containing water as a main solvent. In the coating composition of the present invention, the water content is preferably 20 to 70% by mass. Further, the coating composition of the present invention can be completely water-based, and the proportion of water in the solvent used is preferably 85% by mass or more, and most preferably 100% by mass.

In the water-based coating composition of the present invention, other components such as resin, pigment, surface conditioner, wetting agent, dispersant, emulsifier, thickener, anti-settling agent, anti-skinning agent, anti-sagging agent, and color coding Inhibitors, matting agents, leveling agents, desiccants, plasticizers, film-forming aids, fungicides, preservatives, insecticides, light stabilizers, UV absorbers, antistatic agents, conductivity-imparting agents, etc. It can be appropriately blended according to the purpose. Commercially available products can be preferably used as these components. Further, from the viewpoint of odor, the other components preferably have a boiling point of 260 ° C. or higher.

In some cases, an organic solvent is used as a component to be blended in the water-based coating composition of the present invention. In the coating composition of the present invention, the content of the organic solvent is preferably 15% by mass or less, and most preferably 0% by mass.

The coating composition of the present invention can be prepared by mixing various components appropriately selected as necessary. Further, the coating composition of the present invention is preferably used as a one-component type, and is preferably a room temperature drying type water-based coating composition. The "normal temperature" here is 5 to 35 ° C., and according to the coating composition of the present invention, drying can be performed in a short time of 16 hours or less at 23 ° C. or within 24 hours even at 5 ° C. It is possible.

The coating composition (emulsion coating) of the present invention and the acrylic resin emulsion that can be blended in the coating composition preferably have a minimum film forming temperature of 5 ° C. or lower, and more preferably 0 ° C. or lower. In the present specification, the minimum film forming temperature is measured according to JIS K6828-2: 2003. Further, in order to adjust the minimum film forming temperature, a film forming aid having a boiling point of 260 ° C. or higher can be preferably used.

The coating composition of the present invention has ^{a viscosity of 0.1 s -1 and} a viscosity of 0.1 to 10,000 Pa · s, and a shear rate of 1,000 s ^{-1 has} a viscosity of 0.05 to 10 Pa · s. Is preferable. In the present invention, the viscosity is measured using a rheometer (such as a rheometer ARES manufactured by TA Instruments) after adjusting the liquid temperature to 23 ° C.

The coating composition of the present invention has a viscosity of the coating material before the test in a test according to "7.6 Low temperature stability test" of JIS K5663: 2008 (however, the temperature of the low temperature incubator is maintained at -7 ° C.). The ratio of (A) to the viscosity (B) of the paint after the test: (B) / (A) is preferably 0.99 to 1.30, and more preferably 0.99 to 1.20. It is preferably 0.99 to 1.10, and more preferably 0.90 to 1.10. The viscosity (A) of the paint before the test and the viscosity (B) of the paint after the test are measured by a stormer viscometer at 20 ° C. based on JIS K 5600-2-2: 1999 (unit: KU value). Is).
Since the coating composition of the present invention is a water-based coating material, it freezes when stored in a low-temperature incubator in the above test, but the viscosity ratios (B) / (A) are within the specified range. If it is shown, it can return to its original properties when thawed after freezing, and is excellent in low temperature stability. The viscosity ratio (B) / (A) can be adjusted by adding a reactive emulsifier.

In the coating composition of the present invention, the acrylic resin emulsion is tested in a test according to JIS K5663: 2008 "7.6 Low Temperature Stability Test" (however, the temperature of the low temperature incubator is maintained at -7 ° C.). The ratio of the viscosity (C) of the previous acrylic resin emulsion to the viscosity (D) of the acrylic resin emulsion after the test: (D) / (C) is preferably 0.99 to 1.30, preferably 0.90. It is more preferably ~ 1.20, and even more preferably 0.99 to 1.10. The viscosity (C) of the acrylic resin emulsion before the test and the viscosity (D) of the acrylic resin emulsion after the test are measured by a stormer viscometer at 20 ° C. based on JIS K 5600-2-2: 1999 ( The unit is the KU value).
As for the acrylic resin emulsion, if the viscosity ratio (D) / (C) shows a value in the specified range, the acrylic resin emulsion can return to its original properties when thawed after freezing, and is excellent in low temperature stability. .. The viscosity ratio (D) / (C) can be adjusted by adding a reactive emulsifier.

In the water-based coating composition of the present invention, the ammonia concentration measured by the method for measuring the ammonia concentration shown below is preferably 12 volume ppm or less.
<Measurement method of ammonia concentration>
A 3 L polyvinyl fluoride sampling bag is filled with 3 L of odorless air, 20 g of the coating composition is injected into the sampling bag, and the sampling bag is sealed. Then, after allowing it to stand at 23 ° C. for 30 minutes, the ammonia concentration in the sampling bag is measured using an ammonia gas detector tube.
In the present specification, as the odorless air, general odorless air used for odor analysis can be used, and usually, air from which impurities have been removed by activated carbon is used as odorless air.

Further, in the water-based coating composition of the present invention, the concentration of the unreacted monomer measured by the measuring method shown below is preferably 100 volume ppm or less.
<Method of measuring the concentration of unreacted monomer>
A 3 L polyvinyl fluoride sampling bag is filled with 3 L of odorless air, 20 g of the coating composition is injected into the sampling bag, the sampling bag is sealed, and then the sample is allowed to stand at 23 ° C. for 30 minutes. The concentration of unreacted monomer in the sampling bag is measured using a detector tube capable of detecting the monomer to be used.
In the present specification, as the odorless air, general odorless air used for odor analysis can be used, and usually, air from which impurities have been removed by activated carbon is used as odorless air.

The water-based coating composition of the present invention has an antiviral effect when at least one of the following conditions 1 and 2 is tested for the antiviral activity value (pfu) obtained by the method for measuring the antiviral activity value shown below. The activity value is preferably 2.0 or more, and more preferably 3.0 or more.
<Measurement method of antiviral activity value>
The virus infectivity titer is measured in the following steps in accordance with the method described in JIS R 1756: 2020 "Fine Ceramics-Antiviral Test Method for Visible Light Responsive Photocatalytic Material-Method Using Escherichia Qβ".
1. 1. One side of an acrylic plate (50 mm × 50 mm, thickness: 1 mm) is coated with a coating composition so as to have a dry film thickness of 30 μm, and a coating film is formed to prepare a test piece.
2. Place a sterilized humidity control filter paper on the bottom of the sterilized storage dish, add 5 mL of sterilized water, and then place a glass rod on the humidity control filter paper to prevent the humidity control filter paper from touching the test piece. Place the test piece on the glass rod. At that time, the test piece is installed so that the surface on which the coating film is formed faces up.
3. 3. 0.1 mL of virus solution (specifically, bacteriophage Qβ (NBRC20122) [host Escherichia coli (NBRC106373)], concentration 1.5 × 10 ⁷ pfu / ml) was dropped from the top of the test piece, and the virus on the test piece was dropped. The liquid is coated with a polypropylene film. Then, a moisturizing glass (borosilicate glass) is placed on the top of the storage dish.
4. The test product prepared in step 3 is tested under the following condition 1 or condition 2.
・ Condition 1: Store in a dark box for 4 hours.
-Condition 2: Irradiate with a white fluorescent lamp (FL20SSW / 18, illuminance: 500 lp) for 4 hours.
5. After performing the test of condition 1 or condition 2 in step 4, the virus on the test piece is washed out with SCDLP medium and collected, and the virus infectivity titer (pfu) is measured.
Using the virus infectivity titer measured in step 5, the antiviral activity value (pfu) is calculated from the following formula.
Antiviral activity value (pfu) = Log (A × B) -Log (C)
However,
A: Virus solution concentration (pfu / mL)
B: Amount of virus solution dropped onto the test piece (mL)
C: Virus infectivity titer (pfu) after the test of condition 1 or condition 2.

In the above method for measuring the antiviral activity value, the target virus is bacteriophage Qβ (NBRC20122) [host Escherichia coli (NBRC106373)]. The virus infectious titer is the infectious titer by the plaque measurement method.
In step 1, after preparing the test piece, it may be irradiated with ultraviolet light (FL20S / BLB, 1.0 mW / cm ^{2) for 24 hours for the purpose of removing organic substances.}
The film used in step 3 is a material that does not affect the growth of microorganisms, has no water absorption, and has a transmittance of 340 to 380 nm of 85% or more. For example, a polypropylene film can be used. ..
In step 5, 10 mL of SCDLP medium is used for the virus washout treatment on the test piece.

Further, the antibacterial effect can be evaluated by a method based on, for example, JIS R 1752: 2000.

The coating means of the coating composition of the present invention is not particularly limited, and known coating means such as spray coating, roller coating, brush coating, iron coating, spatula coating and the like can be used.

The object to be coated with the coating composition of the present invention is not particularly limited, and for example, steel, zinc-plated steel (for example, galvanized iron plate), tin-plated steel (for example, tin plate), stainless steel, magnesium alloy, aluminum, etc. Metal base materials such as aluminum alloys, wood, plaster, calcium silicate, glass, ceramics, concrete, cement, mortar, slate and other inorganic base materials, acrylic resin, polyvinyl chloride, polycarbonate, ABS resin, polyethylene terephthalate, polyolefin, etc. Plastic base material can be mentioned. In addition, composite base materials such as wood fiber reinforced cement board, fiber reinforced cement board, fiber reinforced cement and calcium silicate board can also be exemplified. The metal base material also includes a base material that has been subjected to various surface treatments, for example, an oxidation treatment. Further, a plastic base material whose surface is coated with an inorganic substance (for example, a plastic base material coated with a glassy substance) is included in the inorganic base material. The base material may be subjected to a primer treatment, or an old coating film (a coating film already formed when the coating method of the present invention is carried out) is present on at least a part of the surface of the base material. You may be.

In addition, as described above, base materials of various materials can be mentioned as objects to be painted, and specific examples thereof include structures such as buildings and structures, vehicles (automobiles, etc.), furniture, fittings, electronic devices (home appliances, etc.). ) And those parts are preferably mentioned. Here, the coating composition of the present invention is suitable as a coating material for interior and exterior (interior and / or exterior) of a structure. In the present invention, a building means a structure constructed for the purpose of living or staying in a human being, and examples thereof include a house (particularly a detached house or an apartment house), a building, a factory, and the like. It means a structure constructed for purposes other than the purpose of living or staying by humans, and includes, for example, bridges, tanks, plant pipes, chimneys, and the like. Examples of the members of the structure include roofs and walls (inner walls, outer walls, etc., particularly curtain walls).

The coating film of the present invention is a coating film obtained from the above-mentioned water-based coating composition of the present invention. The film thickness of the coating film is, for example, 20 to 80 μm.

The coated article of the present invention is a coated article having a coating film obtained from the above-mentioned water-based coating composition of the present invention, and is preferably a coated article having the coating film on the surface of a base material. Here, the film thickness of the coating film is, for example, 20 to 80 μm.

The details of the base material in the coated article of the present invention are as described in the water-based coating composition of the present invention. The painted article of the present invention includes the surface of the article as described as the object to be painted in the water-based paint composition of the present invention, for example, structures such as buildings and structures, vehicles (automobiles, etc.), furniture, fittings, and electronic devices. (Home appliances, etc.) and those having a coating film on the surface of those parts can be mentioned.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

<Synthesis example 1>
A five-necked flask equipped with a stirrer, a reflux cooling tube, a thermometer, a dropping device, and a nitrogen introduction tube was charged with 200 parts by mass of ion-exchanged water and 6.0 parts by mass of a non-reactive emulsifier, and the inside of the reactor was filled with nitrogen. While substituting, the temperature was raised to 80 ° C., 1.0 part by mass of potassium persulfate was added, and then 190 parts by mass of methyl methacrylate, 250 parts by mass of butyl acrylate, and acrylic acid were previously stirred and mixed in a separate container. A mixture of 10 parts by mass, 220 parts by mass of ion-exchanged water, and 30.0 parts by mass of the non-reactive emulsifier a was continuously added dropwise over 3.5 hours. Then, after aging at 80 ° C. for 2 hours while continuing stirring, a mixture of 2.7 parts by mass of ion-exchanged water and 0.3 parts by mass of a 70% aqueous solution of tert-butyl hydroperoxide was added to the reactor, and then ion exchange was performed. A mixture of 9.7 parts by mass of water and 0.3 parts by mass of sodium elisorbate was continuously added dropwise over 5 minutes. Then, the mixture was aged at 80 ° C. for 2 hours while continuing stirring, cooled to room temperature, and then _{4.0 parts by mass of a 25 mass% ammonia (NH 3} ) aqueous solution was added to adjust the pH to 9.0 to adjust the pH to 9.0, and the resin of Synthesis Example 1 A dispersion was obtained. Synthesis Example 1 Table 1 shows the content (% by mass) of acrylic resin, the glass transition temperature (Tg, ° C.), and the volume average particle size (nm) in the resin dispersion.
The glass transition temperature was obtained from the FOX equation. The volume average particle size was determined using a particle size measuring machine ELS-Z manufactured by Otsuka Electronics Co., Ltd.

<Synthesis Example 2 to Synthesis Example 13>
Acrylic resins were synthesized under the same conditions as in Synthesis Example 1 except that the blending amounts of the raw materials in Synthesis Example 1 were changed to the respective blending amounts in Table 1. Synthesis Example 2 Resin dispersion to Synthesis Example 13 Resin dispersion Was prepared. Table 1 shows the content (% by mass) of acrylic resin, the glass transition temperature (Tg, ° C.), and the volume average particle diameter (nm) in each resin dispersion.
The low temperature stability of the resin dispersion (acrylic resin emulsion) was evaluated by the following method.
Based on the test according to JIS K5663: 2008 "7.6 Low temperature stability test", the container filled with the resin dispersion is sealed, placed in a low temperature constant temperature bath at a temperature of -7 ° C for 18 hours, and then at room temperature (23 ° C). ) Was placed for 6 hours as one cycle, and a total of 3 cycles were repeated. The viscosity (C) of the resin dispersion before the test and the viscosity (D) of the resin dispersion after the test were measured based on JIS K 5600-2-2: 1999, and the viscosity at 20 ° C. was measured with a stormer viscometer (D). ) / (C) is calculated and shown in the item of "Varnish viscosity ratio (D) / (C)" in Table 1.

(Note 1) Non-reactive emulsifier a (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd .: Hytenol NF0825 (anionic))
(Note 2) Reactive emulsifier b (manufactured by Nippon Emulsifier Co., Ltd .: Antox SAD (anion type))
(Note 3) Reactive emulsifier c (manufactured by ADEKA: Adecaria Soap SR-1025 (anionic))
(Note 4) Reactive emulsifier d (manufactured by ADEKA: Adecaria Soap ER-10 (nonion type))

<Comparative example 1>
6.5 parts by mass of ion-exchanged water was added to the mixer, and 1.0 part by mass of the dispersant, 0.2 parts by mass of the defoaming agent, and 20.0 parts by mass of titanium oxide were gradually added to the mixture under a stirring environment. After the addition was completed, the mixture was mixed until the particle size became 50 μm or less. Next, 70.0 parts by mass of the synthetic example 1 resin dispersion, 2.0 parts by mass of the viscosity modifier, and 0.3 parts by mass of the defoaming agent were gradually added to the mixer under a stirring environment, and the mixture was sufficiently mixed. A water-based coating composition of Comparative Example 1 was obtained.

<Comparative Examples 2 and 3>
The water-based coating compositions of Comparative Examples 2 and 3 were obtained by the same method as in Comparative Example 1 except that the resin dispersion of Comparative Example 1 was changed to the resin dispersion of Synthesis Example 2 or the resin dispersion of Synthesis Example 3.

<Example 1>
6.5 parts by mass of ion-exchanged water was added to the mixer, and 1.0 part by mass of the dispersant, 0.2 parts by mass of the defoaming agent, and 20.0 parts by mass of titanium oxide were gradually added to the mixture under a stirring environment. After the addition was completed, the mixture was mixed until the particle size became 50 μm or less. Next, 70.0 parts by mass of the synthetic example 4 resin dispersion, 2.0 parts by mass of the viscosity modifier, and 0.3 parts by mass of the defoaming agent were gradually added to the mixer under a stirring environment, and the mixture was sufficiently mixed. The water-based coating composition of Example 1 was obtained.

<Examples 2 to 10>
The water-based coating composition of Examples 2 to 10 was obtained by the same method as in Example 1 except that the resin dispersion of Example 1 was changed to the resin dispersion shown in Table 3.

<Example 11>
19.0 parts by mass of ion-exchanged water was put into the mixer, and 1.5 parts by mass of the dispersant, 0.2 parts by mass of the defoamer, 22.0 parts by mass of titanium oxide, 5.0 parts by mass of kaolin, and calcium carbonate were added. 15.0 parts by mass of calcium and 5.0 parts by mass of silica were gradually added under a stirring environment, and after the addition, they were mixed until the particle size became 50 μm or less. Next, 30.0 parts by mass of the synthetic example 5 resin dispersion, 1.5 parts by mass of the viscosity modifier, and 0.8 parts by mass of the defoaming agent were gradually added to the mixer under a stirring environment, and the mixture was sufficiently mixed. The water-based coating composition of Example 10 was obtained.

<Examples 12 to 14>
The water-based paint compositions of Examples 12 to 14 were obtained by the same method as in Example 11 except that the resin dispersion of Example 10 was changed to the resin dispersion shown in Table 4.

<Example 15>
Add 19.8 parts by mass of ion-exchanged water and 80 parts by mass of the resin dispersion of Synthesis Example 5 to the mixer, gradually add 0.2 parts by mass of the defoaming agent to this, and mix until uniform. By doing so, the water-based coating composition of Example 15 was obtained.

<Examples 16 to 18>
The water-based coating compositions of Examples 16 to 18 were obtained by the same method as in Example 15 except that the resin dispersion of Example 15 was changed to the resin dispersion shown in Table 4.

<Example 19>
6.5 parts by mass of ion-exchanged water was added to the mixer, and 1.0 part by mass of the dispersant, 0.2 parts by mass of the defoaming agent, and 20.0 parts by mass of titanium oxide were gradually added to the mixture under a stirring environment. After the addition was completed, the mixture was mixed until the particle size became 50 μm or less. Next, 70.0 parts by mass of Synthesis Example 9 resin dispersion, 5.0 parts by mass of antiviral agent dispersion 1, 2.0 parts by mass of viscosity modifier, and 0.3 parts by mass of defoaming agent were stirred in a mixer. After gradually adding underneath and mixing well, the aqueous coating composition of Example 19 was obtained.

<Example 20>
The water-based coating composition of Example 20 was obtained by the same method as in Example 19 except that the amount of the antiviral agent dispersion 1 added was changed from 5.0 parts by mass to 8.0 parts by mass.

<Example 21>
19.0 parts by mass of ion-exchanged water was put into the mixer, and 1.5 parts by mass of the dispersant, 0.2 parts by mass of the defoamer, 22.0 parts by mass of titanium oxide, 5.0 parts by mass of kaolin, and calcium carbonate were added. 15.0 parts by mass of calcium and 5.0 parts by mass of silica were gradually added under a stirring environment, and after the addition, they were mixed until the particle size became 50 μm or less. Next, 30.0 parts by mass of Synthesis Example 9 resin dispersion, 5.0 parts by mass of antiviral agent dispersion 1, 1.5 parts by mass of viscosity modifier, and 0.8 parts by mass of defoaming agent were stirred in a mixer. After gradually adding underneath and mixing well, the aqueous coating composition of Example 21 was obtained.

<Example 22>
The water-based paint composition of Example 22 was carried out in the same manner as in Example 21 except that the antiviral agent dispersion 1 was changed to the antiviral agent aqueous solution 2 and the addition amount was changed from 5.0 parts by mass to 2.5 parts by mass. I got something.

<Example 23>
The water-based paint composition of Example 23 was carried out in the same manner as in Example 21 except that the antiviral agent dispersion 1 was changed to the antiviral agent aqueous solution 3 and the addition amount was changed from 5.0 parts by mass to 8.0 parts by mass. I got something.

<Example 24>
The water-based paint of Example 24 was prepared in the same manner as in Example 21 except that the antiviral agent dispersion 1 was changed to the antiviral agent dispersion 4 and the addition amount was changed from 5.0 parts by mass to 10.0 parts by mass. The composition was obtained.

<Example 25>
19.8 parts by mass of ion-exchanged water was added to the mixer, and 0.2 parts by mass of a defoaming agent was added thereto. Next, 80.0 parts by mass of the synthetic example 9 resin dispersion and 5.0 parts by mass of the antiviral agent dispersion 1 were gradually added to the mixer under a stirring environment, and after sufficient mixing, the aqueous system of Example 25 was used. A coating composition was obtained.

※ 表５の実施例６は、抗ウイルス活性値及び抗菌活性値の評価結果を除き、表３の実施例６と同じデータである。

* Example 6 in Table 5 has the same data as Example 6 in Table 3, except for the evaluation results of the antiviral activity value and the antibacterial activity value.

(Note 5) Dispersant (manufactured by Dow Chemical Co., Ltd .: Orotan 731A)
(Note 6) Antifoaming agent (manufactured by Big Chemie: BYK-038)
(Note 7) Viscosity modifier (manufactured by Dow Chemical Co., Ltd .: PRIMAL RM-2020NPR)
(Note 8) Titanium oxide (manufactured by TAYCA Corporation: JR-806)
(Note 9) Kaolin (manufactured by Takehara Chemical Industry Co., Ltd .: special kaolin)
(Note 10) Calcium carbonate (manufactured by Takehara Chemical Industry Co., Ltd .: Sunlight SL-100)
(Note 11) Silica (manufactured by EP Minerals: Celatom MW-25)
(Note 12) Antiviral agent dispersion 1 (25% by mass aqueous dispersion of titanium oxide carrying a divalent copper compound; prepared according to Preparation Example 1 below)
(Note 13) Antiviral agent aqueous solution 2 (50% by mass aqueous solution of copper (I) (CuCl) chloride)
(Note 14) Antiviral agent aqueous solution 3 (Amorden V-100JM, manufactured by Daiwa Chemical Industries, Ltd., 50% by mass aqueous solution of organic nitrogen bromine compound)
(Note 15) Antiviral agent dispersion 4 (12% by mass aqueous dispersion of H-type carboxyl group-containing polymer; prepared according to Preparation Example 2 below)

<Preparation Example 1>
6 g (100 parts by mass) of rutile-type titanium oxide raw material (BET specific surface area: 10 m ² / g, primary particle size 150 nm) was suspended in 100 mL of distilled water, and 0.0805 g (0.5 parts by mass in terms of copper) was suspended. CuCl ₂ · _{2H 2} O (manufactured by Kanto Chemical Co., Inc.) was added and stirred for 10 minutes. A 1 mol / L sodium hydroxide (manufactured by Kanto Chemical Co., Inc.) aqueous solution was added so that the pH became 10, and the mixture was stirred and mixed for 30 minutes to obtain a slurry. The slurry was filtered, the obtained powder was washed with pure water, dried at 80 ° C., and crushed with a mixer to obtain an antiviral agent 1 (photocatalyst). 75 g of distilled water was added to 125 g of the antiviral agent to carry out a dispersion treatment to prepare an antiviral agent dispersion liquid 1.

<Preparation Example 2>
30 parts by mass of a monomer mixture consisting of 58% by mass of acrylonitrile, 9% by mass of methyl acrylate, 30% by mass of divinylbenzene, and 3% by mass of sodium p-styrene sulfonate, containing 1.2% by mass of ammonium persulfate in terms of monomer ratio. It was added to 70 parts by mass of the aqueous solution, charged into a polymerization tank equipped with a stirrer, and then polymerized at 135 ° C. for 25 minutes. To 90 parts by mass of the obtained polymer emulsion, 10 parts by mass of a 40% by mass sodium hydroxide aqueous solution was added, and hydrolysis was carried out at 95 ° C. By adjusting the reaction time at this time, the amount of carboxyl groups of the antiviral particles was adjusted to 5.0 mmol / g. Distilled water was added to the obtained emulsion to adjust the solid content concentration to 12% by mass, and then the pH was adjusted to 2.5 with a cation exchange resin to make the carboxyl group H-type, and the antiviral agent dispersion 2 was obtained. It was.

The volume average particle size of the acrylic resin in the obtained water-based paint composition was almost the same as the volume average particle size of the resin dispersion liquid in which each of the blended resins was blended.

The obtained coating composition was evaluated as follows. The results are shown in Tables 2 to 6.

<Ammonia concentration>
A 3 L polyvinyl fluoride sampling bag was filled with 3 L of odorless air treated with activated carbon, 20 g of paint was injected into the 3 L sampling bag, and the bag was sealed. Then, after allowing to stand in a room at room temperature of 23 ° C. for 30 minutes, the ammonia concentration was measured using an ammonia gas detector tube manufactured by Gastec.

<Odor>
50 g of the paint was taken in a 100 ml glass bottle, and a sensory test of odor was carried out by 10 panelists in a room at room temperature of 23 ° C. Evaluate on a three-point scale of "no odor", "slightly odor", and "odor", and add 0 points for "no odor", 1 point for "slightly odor", and 2 points for "odor". Therefore, the paint odor was evaluated. The evaluation criteria are as follows.
⊚: The total score of 10 people is 2 points or less.
◯: The total score of 10 people is 4 points or less.
X: The total score of 10 people is 5 points or more.

<Low temperature stability of paint>
Based on the test according to JIS K5663: 2008 "7.6 Low temperature stability test", the container filled with the paint was sealed. A cycle of placing the closed container in a low-temperature constant temperature bath at a temperature of −7 ° C. for 18 hours and then leaving it at room temperature (23 ° C.) for 6 hours was set as one cycle, and a total of 3 cycles were repeated. The viscosity (A) of the paint before the test and the viscosity (B) of the paint after the test were measured based on JIS K 5600-2-2: 1999, and the viscosity at 20 ° C. was measured with a Stormer viscometer, and (B) / (A). ) Was calculated. The evaluation criteria for low temperature stability were as follows.
◯: The value of (B) / (A) is 0.99 to 1.30. ×: The value of (B) / (A) is higher than 1.30.

<Low temperature film formation>
When the paint was applied to a 150 x 70 x 2 mm glass plate under the condition of 5 ° C. with a 6 mil applicator, dried under the same conditions for 24 hours, and then returned to room temperature (23 ° C.), the coating film was applied. The low temperature film forming property was evaluated according to the following criteria from the appearance of.
◯: No abnormality such as cracking or peeling in the coating film ×: Abnormality such as cracking or peeling in the coating film

<Water resistance>
Under standard conditions (temperature 23 ° C., relative humidity 50%), a paint was applied to a 150 × 70 × 4 mm flexible plate with a brush. After drying for 6 hours, the second layer was similarly applied and dried for 5 days to obtain a test piece. The obtained test piece was immersed in ion-exchanged water (23 ° C.) for 14 days and then taken out, and the water resistance was evaluated according to the following criteria from the appearance of the test piece 2 hours after taking out.
◯: No abnormality such as wrinkles, swelling, cracking and peeling, and no significant change in gloss ×: Abnormality such as wrinkles, swelling, cracking and peeling, or large change in gloss

<Antiviral property>
The antiviral activity value was measured in the following steps in accordance with the method described in JIS R 1756: 2020 "Fine Ceramics-Antiviral Test Method for Visible Light Responsive Photocatalytic Material-Method Using Escherichia Qβ". The test instrument was sterilized by wiping with absolute ethanol.
1. 1. One side of an acrylic plate (50 mm × 50 mm, thickness: 1 mm) was coated with a coating composition so as to have a dry film thickness of 30 μm, and a coating film was formed to prepare a test piece. After preparing the test piece, it was irradiated with ultraviolet light (FL20S / BLB, 1.0 mW / cm ² ) for 24 hours to remove organic substances.
2. Place a sterilized humidity control filter paper on the bottom of the sterilized storage dish, add 5 mL of sterilized water, and then place a glass rod on the humidity control filter paper to prevent the humidity control filter paper from touching the test piece. A test piece was placed on a glass rod. At that time, the test piece was placed so that the surface on which the coating film was formed faced up.
3. 3. From the top of the test piece, 0.1 mL of virus solution (bacteriophage Qβ (NBRC20122) [host Escherichia coli (NBRC106373)], concentration 1.5 × 10 ⁷ pfu / ml) was dropped, and the virus solution on the test piece was coated with a polypropylene film. It was coated with (40 mm × 40 mm, VF-10, manufactured by KOKUYO, thickness: 0.06 mm). Then, a moisturizing glass (borosilicate glass) was placed on the upper part of the storage petri dish.
4. The test product prepared in step 3 was tested under the following condition 1 or condition 2.
・ Condition 1: Store in a dark box for 4 hours.
-Condition 2: Irradiate with a white fluorescent lamp (FL20SSW / 18, illuminance: 500 lp, sharp cut filter: Type B (cut wavelengths of N169 and 380 nm or less)) for 4 hours.
5. After conducting the test of condition 1 or condition 2 in step 4, the virus on the test piece was washed out with SCDLP medium and collected, and the virus infectivity titer (PFU) was measured.
Using the virus infectivity titer measured in step 5, the antiviral activity value (pfu) was calculated by the following formula.
Antiviral activity value (pfu) = Log (A × B) -Log (C)
However,
A: Virus solution concentration (pfu / mL)
B: Amount of virus solution dropped onto the test piece (mL)
C: Virus infectivity titer (pfu) after the test of condition 1 or condition 2.

<Antibacterial property>
The antibacterial activity value was measured in the following steps in accordance with the method described in JIS R 1752: 2020 "Fine Ceramics-Visible Light Responsive Photocatalytic Antibacterial Processed Material Antibacterial Test Method and Antibacterial Effect". The test instrument was sterilized by wiping with absolute ethanol.
1. 1. One side of an acrylic plate (50 mm × 50 mm, thickness: 1 mm) was coated with a coating composition so as to have a dry film thickness of 30 μm, and a coating film was formed to prepare a test piece. After preparing the test piece, it was irradiated with ultraviolet light (FL20S / BLB, 1.0 mW / cm ² ) for 24 hours to remove organic substances.
2. Place a sterilized humidity control filter paper on the bottom of the sterilized storage dish, add 5 mL of sterilized water, and then place a glass rod on the humidity control filter paper to prevent the humidity control filter paper from touching the test piece. A test piece was placed on a glass rod. At that time, the test piece was placed so that the surface on which the coating film was formed faced up.
3. 3. From the top of the test piece, 0.1 mL of the bacterial solution (Staphylococcus aureus (NBRC12732), concentration 1.8 × 10 ⁶ cfu / ml) was dropped, and the bacterial solution on the test piece was coated with a polypropylene film (40 mm × 40 mm, VF-). 10. Made by KOKUYO, thickness: 0.06 mm). Then, a moisturizing glass (borosilicate glass) was placed on the upper part of the storage petri dish.
4. The test product prepared in step 3 was tested under the following condition 1 or condition 2.
・ Condition 1: Store in a dark box for 8 hours.
-Condition 2: Irradiate with a white fluorescent lamp (FL20SSW / 18, illuminance: 500 lp, sharp cut filter: TypeB (N169, cut wavelengths of 380 nm or less)) for 8 hours.
5. After conducting the test of condition 1 or condition 2 in step 4, the virus on the test piece was washed out with SCDLP medium and collected, and the viable cell count (cfu) was measured.
Using the viable cell count measured in step 5, the antibacterial activity value (cfu) was calculated by the following formula.
Antibacterial activity value (cfu) = Log (D × E) -Log (F)
However,
D: Concentration of antibacterial solution (cfu / mL)
E: Amount of antibacterial solution dropped onto the test piece (mL)
F: Viable cell count (cfu) after the test of condition 1 or condition 2.

Claims (12)

The acrylic resin contains an acrylic resin containing a structural unit derived from a reactive emulsifier and a neutralizing agent selected from the group consisting of an alkaline inorganic compound excluding ammonia and an alkaline organic compound having a boiling point of more than 260 ° C. A water-based paint composition characterized in that it is dispersed in the water-based paint composition in the form. The water-based coating composition according to claim 1, wherein the reactive emulsifier is a nonionic reactive emulsifier. The water-based coating composition according to claim 1 or 2, wherein the reactive emulsifier has a polyalkylene glycol chain. The water-based coating composition according to any one of claims 1 to 3, wherein the neutralizing agent is sodium hydroxide. The water-based coating composition according to any one of claims 1 to 4, wherein the acrylic resin has a volume average particle diameter of 30 to 300 nm. The water-based coating composition according to any one of claims 1 to 5, wherein the acrylic resin has a glass transition temperature of 0 ° C. or lower. The water-based paint composition according to any one of claims 1 to 6, wherein the water-based paint composition is a room temperature dry type water-based paint composition. In the test according to JIS K5663: 2008 "7.6 Low Temperature Stability Test" (however, the temperature of the low temperature incubator is kept at -7 ° C), the viscosity (A) of the paint before the test and the paint after the test The water-based coating composition according to any one of claims 1 to 7, wherein the ratio of the viscosity (B) of (B): (B) / (A) is 0.99 to 1.20. The water-based coating composition according to any one of claims 1 to 8, wherein the ammonia concentration measured by the method for measuring the ammonia concentration shown below is 12 volume ppm or less.
<Measurement method of ammonia concentration>
A 3 L polyvinyl fluoride sampling bag is filled with 3 L of odorless air, 20 g of the coating composition is injected into the sampling bag, and the sampling bag is sealed. Then, after allowing it to stand at 23 ° C. for 30 minutes, the ammonia concentration in the sampling bag is measured using an ammonia gas detector tube. Regarding the antiviral activity value (pfu) obtained by the method for measuring the antiviral activity value shown below, the antiviral activity value when at least one of the following conditions 1 and 2 is tested is 2.0 or more. The water-based coating composition according to any one of claims 1 to 9, wherein the water-based coating composition is characterized by the above.
<Measurement method of antiviral activity value>
The virus infectivity titer is measured in the following steps in accordance with the method described in JIS R 1756: 2020 "Fine Ceramics-Antiviral Test Method for Visible Light Responsive Photocatalytic Material-Method Using Escherichia Qβ".
1. 1. One side of an acrylic plate (50 mm × 50 mm, thickness: 1 mm) is coated with a coating composition so as to have a dry film thickness of 30 μm, and a coating film is formed to prepare a test piece.
2. Place a sterilized humidity control filter paper on the bottom of the sterilized storage dish, add 5 mL of sterilized water, and then place a glass rod on the humidity control filter paper to prevent the humidity control filter paper from touching the test piece. Place the test piece on the glass rod. At that time, the test piece is installed so that the surface on which the coating film is formed faces up.
3. 3. 0.1 mL of the virus solution is dropped from the top of the test piece, and the virus solution on the test piece is coated with a polypropylene film. Then, a moisturizing glass (borosilicate glass) is placed on the top of the storage dish.
4. The test product prepared in step 3 is tested under the following condition 1 or condition 2.
・ Condition 1: Store in a dark box for 4 hours.
-Condition 2: Irradiate with a white fluorescent lamp (illuminance: 500 lp) for 4 hours.
5. After performing the test of condition 1 or condition 2 in step 4, the virus on the test piece is washed out with SCDLP medium and collected, and the virus infectivity titer (pfu) is measured.
Using the virus infectivity titer measured in step 5, the antiviral activity value (pfu) is calculated from the following formula.
Antiviral activity value (pfu) = Log (A × B) -Log (C)
However,
A: Virus solution concentration (pfu / mL)
B: Amount of virus solution dropped onto the test piece (mL)
C: Virus infectivity titer (pfu) after the test of condition 1 or condition 2. A coating film obtained from the water-based coating composition according to any one of claims 1 to 10. A coated article having a coating film obtained from the water-based coating composition according to any one of claims 1 to 10 on the surface of a base material.