JP2010174184A - Water paint composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water paint composition which can be stored and maintained stably for a long period as a coating material and from which a coating film for efficiently adsorbing harmful air pollutant such as formaldehyde, ammonia or mercaptan contained in the air of indoor or outdoor through a long period can be formed and which is excellent in following capability to a ground. <P>SOLUTION: The water paint composition contains a water-based resin dispersed body (A) containing a surfactant copolymerizable with an α,β-ethylenic unsaturated monomer and an ethylenic unsaturated monomer having carboxy group as essential ingredients in which 0.5-10 mass% of ethylenic unsaturated monomer having carbonyl group except the carboxy group is copolymerized, a compound (B) having two or more hydrazide groups in a molecule and activated carbon (C), wherein the average particle diameter measured by dynamic light scattering method is larger than the average pore diameter of the activated carbon. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an aqueous coating composition, and more particularly to an aqueous coating composition from which a coating film for building interiors can be obtained.

  In recent years, with the improvement in the sealing of houses, the sick building syndrome due to formaldehyde contained in furniture and building materials, the decay of cigarettes, food and drink, harmful substances such as odors from pets, and deterioration of the indoor environment due to unpleasant substances have been screamed. long. In order to reduce these, porous and adsorbing substances such as activated carbon, diatomaceous earth, and activated zinc white are widely used.

  In paints, the transition from paints that use volatile organic solvents to water-based paints, and the use of porous, adsorptive activated carbon and diatomaceous earth to absorb harmful and unpleasant substances as described above. Many paints used have been reported and commercialized (see Patent Documents 1 to 4).

  However, when activated carbon is added to the water-based paint, the higher the ratio of the activated carbon, the more the storage stability of the water-based paint deteriorates by adsorbing the surfactant of the emulsion resin, resulting in increased viscosity, aggregation, gelation, etc. It sometimes led to a phenomenon. Further, when the average pore diameter of the activated carbon is larger than the average particle diameter of the emulsion resin, the emulsion resin itself may be adsorbed. In order to improve it, before adding it to the emulsion resin, it is possible to ensure storage stability after making it a paint by adding activated carbon, surfactant, wetting agent, etc. There was a problem that the adsorption capacity of the activated carbon was reduced or lost.

  Furthermore, in order to increase the adsorption amount of harmful substances and unpleasant substances in the obtained coating film, when the ratio of activated carbon was increased, the coating film was fragile and could not follow the expansion and contraction of the base material, and often cracked. .

JP 11-29742 A Japanese Patent No. 3694462 JP-A-5-255621 JP 2001-348302 A

  Accordingly, an object of the present invention is to enable stable storage and storage as a paint for a long period of time, and to efficiently remove harmful air pollutants such as formaldehyde, ammonia, and mercaptans contained in indoor and outdoor air. And it is providing the water-based coating composition which can form the coating film which can adsorb | suck over a long period of time, and is excellent also in the followable | trackability to a foundation | substrate.

According to the present invention, a surfactant copolymerizable with an α, β-ethylenically unsaturated monomer, and an ethylene having a carbonyl group excluding the carboxyl group, the essential component being an ethylenically unsaturated monomer having a carboxyl group Aqueous resin dispersion (A) copolymerized with 0.5% to 10% by weight of unsaturated unsaturated monomer, compound (B) having two or more hydrazide groups in the molecule, and activated carbon (C) An aqueous coating composition comprising:
An aqueous coating composition is provided in which the average particle diameter of the aqueous dispersion measured by a dynamic light scattering method is larger than the average pore diameter of the activated carbon.

  The aqueous paint composition of the present invention can be stably stored and stored as a paint for a long period of time, and efficiently removes harmful air pollutants such as formaldehyde, ammonia and mercaptans contained in indoor and outdoor air. It is possible to form a coating film that can be adsorbed for a long period of time and has excellent followability to the ground.

  Hereinafter, embodiments of the present invention will be described in detail.

  As a result of intensive studies to solve such problems, the present inventors have found that a surfactant copolymerizable with an α, β-ethylenically unsaturated monomer and an ethylenically unsaturated monomer having a carboxyl group Is an essential component, and an aqueous resin dispersion (A) in which an ethylenically unsaturated monomer having a carbonyl group excluding a carboxyl group is copolymerized in an amount of 0.5 to 10% by mass, and two hydrazide groups in the molecule An aqueous coating composition containing the compound (B) having the above and activated carbon (C), wherein the average particle diameter measured by the dynamic light scattering method of the aqueous dispersion is larger than the average pore diameter of the activated carbon. It has been found that the above problem can be solved by being characterized by being large.

  The aqueous resin dispersion (A) constituting the aqueous coating composition of the present invention has a carbonyl group in the presence of a surfactant copolymerizable with an α, β-ethylenically unsaturated monomer in water. An aqueous resin dispersion obtained by copolymerizing an ethylenically unsaturated monomer and other copolymerizable ethylenically unsaturated monomers, and a polymerization method such as an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, etc. In addition, a monomer batch charging method in which monomers are charged in a batch, a monomer dropping method in which monomers are continuously dropped, a monomer, water and an emulsifier are mixed and emulsified in advance. In addition, a pre-emulsion method in which this is dropped, or a combination of these can be used, and it is also possible to use a single-step or a multi-step dropping method with two or more steps.

  Typical examples of the emulsion polymerization method include an ethylenically unsaturated monomer having a carbonyl group and other copolymerizable ethylenic monomers in the presence of a polymerization initiator in water and, if necessary, a chain transfer agent. A mixture of saturated monomers, and a pre-emulsion premixed with water and a surfactant copolymerizable with an ethylenically unsaturated monomer are usually added dropwise at 60 to 90 ° C. for emulsion polymerization. The method of obtaining an aqueous resin dispersion by this is mentioned.

  As the polymerization initiator, those conventionally used for radical polymerization can be used, and water-soluble ones are suitable, for example, persulfates such as potassium persulfate and ammonium persulfate; 2,2′-azobis (2-aminodipropane) hydrochloride, 4,4′-azobis-cyanovaleric acid, 2,2′azobis (2-methylbutanamidoxime) dihydrochloride tetrahydrate, etc. Azo-based compounds; peroxides such as hydrogen peroxide and t-butyl hydroperoxide. Furthermore, a redox system in which a reducing agent such as L-ascorbic acid or sodium thiosulfate is combined with ferrous sulfate or the like can also be used.

  Examples of the chain transfer agent include long-chain alkyl mercaptans such as n-dodecyl mercaptan, aromatic mercaptans, halogenated hydrocarbons, and styrene dimers.

  In addition, as a general aqueous resin dispersion, polyvinyl alcohol, hydroxyethyl cellulose, polyvinyl pyrrolidone, or the like may be used as an emulsion stabilizer. However, in the present invention, in order to inhibit harmful activated carbon and adsorption of unpleasant substances. It is preferable not to use.

  In addition, as a surfactant that can be copolymerized with an α, β-ethylenically unsaturated monomer, which is essential in the present invention, a polyoxy having a polymerizable carbon-carbon unsaturated double bond in the molecule is used. Ethylene-1- (allyloxymethyl) alkyl ether sulfate ammonium salt (Product Example: Aqualene KH-10 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), α-sulfo-ω- (i ((nonylphenoxy) methyl-2- ( 2-propenyloxy) ethoxy-poly (oxy-1,2-ethanediylammonium salt (product example: Adeka Soap SE10 manufactured by ADEKA Corporation), polyoxyethylenepropenyl alkylphenyl ether sulfate ammonium salt (product example: first Aquarene BC10 manufactured by Kogyo Seiyaku Co., Ltd., polyoxyalkylene alkenyl ether ammonium sulfate ( Product examples: Anionic surfactants such as LATEMUL PD104 manufactured by Kao Co., Ltd. Furthermore, nonionic surfactants whose terminal groups are —OH groups in the above-described skeleton are also mentioned, and these are used alone or Two or more types can be used in combination, while non-reactive surfactants that are not copolymerizable with the α, β-ethylenically unsaturated monomer enter the pores of the activated carbon and adsorb it. In order not only to significantly reduce the ability, but also to reduce the water resistance of the coating composition, it is preferably not contained in the aqueous resin dispersion (A).

  Next, the ethylenically unsaturated monomer used for forming the aqueous resin dispersion will be described. As described above, the ethylenically unsaturated monomer having a carboxyl group and the ethylenically unsaturated monomer having a carbonyl group excluding the carboxyl group contain 0.5% by mass to 10% by mass as essential components. is there. Examples of the ethylenically unsaturated monomer having a carboxyl group include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, itaconic acid half ester, maleic acid, maleic acid half ester, and the like. These can be used without particular limitation. The ethylenically unsaturated monomer having a carboxyl group can obtain excellent storage stability, mechanical stability, and the like by neutralization with ammonia, amines, inorganic salts, and the like after polymerization. On the other hand, examples of the monomer having a carbonyl group excluding a carboxyl group include acrolein, diacetone (meth) acrylamide, formysterol, (meth) acryloxyalkylpropanal, diacetone (meth) acrylate, and acetonyl (meth). Examples include acrylate, acetoacetoxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate-acetyl acetate, butanediol-1,4-acrylate-acetyl acrylate, vinyl methyl ketone, vinyl ethyl ketone, and vinyl isobutyl ketone. Among these, acrolein, diacetone acrylamide, and vinyl methyl ketone are particularly preferable.

  These ethylenically unsaturated monomers having a carbonyl group cannot form sufficient cross-linking between particles, which is less than 0.5% by mass in the total ethylenically unsaturated monomers forming the aqueous resin dispersion. The elasticity of the coating film cannot be obtained, and the substrate followability is lowered. On the contrary, if it exceeds 10% by mass, the water resistance and the like are lowered, which is not preferable.

  In addition, as the comonomer copolymerized with the ethylenically unsaturated monomer having a carbonyl group, various ethylenically unsaturated monomers conventionally used in the production of acrylic resins can be used without particular limitation. .

Specifically, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, pentyl ( (Meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, α-chloroethyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, (Meth) acrylate monomers such as methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, methoxypropyl (meth) acrylate, and ethoxypropyl (meth) acrylate;
Styrene monomers such as styrene, methylstyrene, chlorostyrene, methoxystyrene;
Hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2 (3) -hydroxypropyl (meth) acrylate, 4-hydroxybutyl acrylate, mono (meth) acrylate of allyl alcohol polyhydric alcohol;
Amide group-containing monomers such as (meth) acrylamide and maleamide;
Amino group-containing monomers such as 2-aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 3-aminopropyl (meth) acrylate, 2-butylaminoethyl (meth) acrylate, and vinylpyridine;
Epoxy group-containing monomers and oligomers obtained by reaction of glycidyl (meth) acrylate, allyl glycidyl ether, an epoxy compound having two or more glycidyl groups and an ethylenically unsaturated monomer having an active hydrogen atom;
Other typical examples include N-methylol acrylamide having an N-methylol group, vinyl acetate, vinyl chloride, and further ethylene, butadiene, acrylonitrile, dialkyl fumarate, and the like. Can do.

Furthermore, divinylbenzene, ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and other monomers having two or more polymerizable unsaturated double bonds in the molecule are used. how to;
Combining monomers having functional groups that react with each other at the temperature during the emulsion polymerization reaction, for example, ethylenically unsaturated monomers having a functional group in combination such as a carboxyl group and a glycidyl group, or a hydroxyl group and an isocyanate group Using a monomer mixture selectively containing
Silyl group-containing ethylenically unsaturated monomers such as (meth) acryloxypropyltrimethoxysilane, (meth) acryloxypropyltriethoxysilane, and (meth) acryloxypropylmethyldimethoxysilane that undergo hydrolysis condensation reactions A method using a monomer mixture contained;
It is also possible to use together.

  Moreover, it is essential that the average particle diameter measured by the dynamic light scattering method of an aqueous dispersion (A) is larger than the average pore diameter of activated carbon (C). The average pore diameter of the activated carbon (C) is generally 1 nm to 30 nm. When the average particle diameter measured by the dynamic light scattering method of the aqueous resin dispersion (A) obtained by the above method is 30 nm or less, which is smaller than the average pore diameter of the activated carbon (C), an aqueous solution is formed in the pores of the activated carbon. Since the resin dispersion enters, the stability of the coating composition and the ability to adsorb harmful substances and unpleasant substances in the resulting coating film are significantly reduced. Therefore, the average particle diameter of the aqueous resin dispersion (A) is larger than the average pore diameter of the activated carbon (C), that is, 30 nm, preferably 50 nm or more, more preferably, the particle size distribution depending on the measured light scattering intensity. It is preferable that the minimum value of be larger than 30 nm because the stability of the paint and the adsorption ability of activated carbon are not lowered.

  Examples of the compound (B) containing 2 or more, preferably 2 to 3 hydrazide groups in the molecule include carbohydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, and adipic acid dihydrazide. And sebacic acid dihydrazide, dodecanedioic acid dihydrazide, isophthalic acid dihydrazide, citric acid trihydrazide, 1,2,4-benzenetrihydrazide, thiocarbodihydrazide and the like. Among these, carbohydrazide, adipic acid dihydrazide, and succinic acid dihydrazide are preferable from the standpoints of dispersibility in water-based coating compositions and water resistance.

  (B) The compounding quantity of a component becomes 0.1-2.0 equivalent with respect to 1 equivalent of carbonyl groups of an aqueous resin dispersion (A), Preferably it becomes 0.3-1.2 equivalent hydrazide group. A quantity is appropriate.

  If the amount of the component (B) is less than the above range, the reaction with the carbonyl group contained in the aqueous resin dispersion becomes insufficient, and it becomes impossible to follow the expansion and contraction of the base material. The component (B) of the reaction remains in the coating film, and the water resistance and the like tend to decrease.

  The activated carbon (C) used in the present invention is, for example, Bincho charcoal produced by baking ash beetle at a high temperature of 900 to 1400 ° C., preferably 1000 to 1200 ° C., and then rapidly cooling with ash and earth in a suitable amount of water. Baked representative charcoal, oak, kunugi, hiba, cedar, etc. are baked at 400-800 ° C and naturally cooled. Plant materials such as bamboo charcoal produced, other rice husks, walnut husks, sugarcane squeezed sugar, and other raw materials such as coal, as well as mineral materials such as coal, for high temperature carbonization using gas such as steam, carbon dioxide, air, etc. Then, they are pulverized to a particle size of 300 mesh or less, and these can be used alone or in combination of two or more without limitation. The particle diameter of the activated carbon (C) is preferably 0.1 to 10 μm, more preferably 1 to 3 μm. By making the activated carbon into a fine powder form, the surface area is increased and the adsorption ability is improved, so that the effects of the present invention can be further extracted. By setting the calcination temperature of the activated carbon to 1000 to 1200 ° C., the activated carbon exhibits basic properties and comes to adsorb acidic substances well, and also has a function as an electromagnetic wave adsorbent with conductive (semiconductor) characteristics. To come out.

  As the pigment used in the aqueous coating composition of the present invention, pigments such as colored pigments and extender pigments that are usually used in the paint field can be used without particular limitation.

  Examples of coloring pigments include white pigments such as titanium oxide; black pigments such as carbon black, acetylene black, lamp black, bone black, graphite, iron black, and aniline black; yellow iron oxide, titanium yellow, monoazo yellow, condensed azo yellow, Yellow pigments such as azomethine yellow, bismuth vanadate, benzimidazolone, isoindolinone, isoindoline, quinophthalone, benzidine yellow, permanent yellow; orange pigments such as permanent orange; red iron oxide, naphthol AS azo red, ansanthrone, anthra Red pigments such as quinonyl red, perylene maroon, quinacridone red pigment, diketopyrrolopyrrole, watching red, permanent red; cobalt purple, quinacridone violet, dioxazine violet And the like can be given; bets like violet pigment; green pigment such as phthalocyanine green; cobalt blue, phthalocyanine blue, blue pigments such as vat blue.

  Examples of extender pigments include barita powder, precipitated barium sulfate, barium carbonate, calcium carbonate, gypsum, clay, silica, zinc dust, white carbon, diatomaceous earth, talc, magnesium carbonate, alumina white, gloss white, mica powder, etc. Can do. Further, when a design property is required, a bright pigment can also be used. As the bright pigment, for example, metallic pigments such as aluminum powder, bronze powder, copper powder, tin powder, lead powder and iron phosphide; Pearl pigments such as metallic metal-coated mica powder and mica-like iron oxide.

The aqueous coating composition of the present invention can contain a thickener and a rheology control agent from the viewpoint of storage stability and coating workability. As such a thickener, conventionally known ones can be used without limitation, and specifically, for example,
Inorganic thickeners such as silicate, metal silicate, montmorillonite, organic montmorillonite, colloidal alumina;
Polyacrylic acid thickeners such as polyacrylic acid soda, polyacrylic acid- (meth) acrylic acid ester copolymer;
“UH-814N”, “UH-462”, “UH-420”, “UH-472”, “UH-540” (manufactured by Asahi Denka), “SN thickener 612”, “SN thickener 621N”, Urethane associative thickeners such as “SN thickener 625N” and “SN thickener 627N” (manufactured by San Nopco);
Fibrin derivative thickeners such as carboxymethylcellulose, methylcellulose, and hydroxyethylcellulose;
Protein thickeners such as casein, sodium caseinate, ammonium caseinate;
Alginate thickeners such as sodium alginate;
Polyvinyl thickeners such as polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl benzyl ether copolymer;
Polyether thickeners such as pluronic polyethers, polyether dialkyl esters, polyether dialkyl ethers, polyether epoxy modified products;
Maleic anhydride copolymer thickeners such as partial esters of vinyl methyl ether-maleic anhydride copolymer;
Examples thereof include polyamide thickeners such as polyamide amine salts, and these can be used alone or in combination of two or more.

  If necessary, the aqueous coating composition of the present invention further includes an ultraviolet absorber, a light stabilizer, a surface conditioner, a basic neutralizer, an antiseptic, an antibacterial agent, an antifungal / algaeproofing agent, and an antifoaming agent. An antifoaming agent can be blended. However, the total amount of surfactant contained in the pigment dispersant, wetting agent, and other additives is preferably 3 parts by mass or less, more preferably 1 part by mass with respect to 100 parts by mass of the coating composition. It is as follows. Specifically, for example, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene stearyl ether; polyoxyethylene alkyl ether, polyoxyethylene distyrylated phenyl ether, polyoxyethylene polyoxypropylene glycol; Non-reactive nonionic surfactants such as sorbitan fatty acid esters such as polyoxyalkylene derivatives such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate sorbitan distearate, sodium lauryl sulfate, ammonium lauryl sulfate; Such as alkyl sulfate ester salts such as sodium polyoxyethylene nonylphenyl ether sulfate, sodium polyoxyethylene lauryl ether sulfate; Oxyethylene alkyl ether sulfates, sodium dodecylbenzene sulfonate, sodium dialkyl sulfosuccinate, sodium alkyl diphenyl ether disulfonate; alkyl benzene sulfonates such as sodium salt of β-naphthalene sulfonic acid formalin condensate, polyoxyethylene polycyclic phenyl Non-reactive anionic surfactants such as sodium sulfate and polycarboxylic acid type polymer surfactants may be mentioned. These non-reactive surfactants enter into the pores of the activated carbon and not only significantly reduce their adsorption ability, but also reduce the water resistance of the coating composition.

  In addition, for the purpose of assisting film formation of the aqueous resin composition, volatile organic compounds such as, for example, alkylene glycol such as ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, dipropylene glycol monomethyl ether; Acetate organic solvent such as ether organic solvent, diethylene glycol monobutyl ether acetate; 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate and the like can be appropriately added, but boiling point is 50 ° C to 150 ° C. The volatile organic solvent is preferably not contained.

  The aqueous coating composition of the present invention thus obtained has, as the coated surface, iron, aluminum, brass, copper plate, stainless steel plate, tin plate, galvanized steel plate, alloyed zinc (Zn—Al, Zn—). Ni, Zn-Fe, etc.) Metals such as plated steel sheets; Surface-treated metals obtained by subjecting these metal surfaces to chemical conversion treatment such as zinc phosphate treatment and chromate treatment; Materials to be coated such as plastic, wood, concrete, and d-mortar It can be applied to the surface, or the surface of the material to be coated, such as a coating surface obtained by applying a primer or the like undercoat and / or an intermediate coat and / or a topcoat. Furthermore, there are no particular limitations on the coating means for applying the aqueous coating composition of the present invention, such as spray coating, electrostatic coating, brush coating, roller coating, etc., and the drying method can be any of heat drying, forced drying, and room temperature drying. It may be.

  Next, an Example is given and this invention is demonstrated more concretely.

  Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, “parts” and “%” are based on mass unless otherwise specified.

Production of aqueous resin dispersion (A1 to A4) In a reactor equipped with a stirrer, a thermometer, a condenser tube and a dropping device, 240 parts of ion-exchanged water, 0.5 part of sodium hydrogen carbonate salt (pH adjuster), 2 parts of polyoxyethylene-1- (allyloxymethyl) alkyl ether sulfate ammonium salt (reactive anionic surfactant; Aqualene KH-10 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was charged respectively, and the inside of the reactor was filled with nitrogen. After the temperature was raised to 80 ° C. while replacing, 1.5 parts of potassium persulfate (polymerization initiator) was added, and then the emulsions (a1 to a4) shown in Table 1 previously stirred and mixed in a separate container. ) Was continuously dripped over 3 hours. After completion of the dripping, the mixture was aged while continuing stirring at 80 ° C. for 2 hours, cooled to 40 ° C., adjusted to pH 9.0 with 28% ammonia water, By scattering method The average particle size measured, respectively 100 nm (minimum 50 nm), 95 nm (minimum 50 nm), 105 nm (minimum 50 nm), to give aqueous resin dispersion of 90 nm (minimum 50 nm) a (Al to A4).

  In addition, about the measurement of a particle diameter, the OPARKA Electronics make and FPAR1000 were used, it measured by the dynamic light scattering method, and the average value by scattering intensity was used.

Manufacture of aqueous resin dispersion (A5) In a reactor equipped with a stirrer, a thermometer, a cooling pipe and a dropping device, 525 parts of ion-exchanged water, ammonium polyoxyethylene-1- (allyloxymethyl) alkyl ether sulfate 10 parts of a salt (reactive anionic surfactant; Aqualene KH-10 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was charged, and the temperature inside the reactor was replaced with nitrogen. 1.5 parts of a polymerization initiator) was added, and then the emulsion (a5) shown in Table 1 previously stirred and mixed in a separate container was continuously added dropwise over 3 hours. The mixture was aged with stirring for 2 hours, cooled to 40 ° C., adjusted to pH 9.0 with 28% aqueous ammonia, and an average particle size of 30 nm (minimum value 5 nm) measured by dynamic light scattering method. A fat dispersion (A5) was obtained.

Production of Aqueous Resin Dispersion (A6) In the production of aqueous resin dispersion (A1), the surfactant is a non-reactive anionic surfactant; polyoxyethylene distyrylated phenyl ether ammonium sulfate (Daiichi Kogyo Seiyaku Hitenol) NF08) Aqueous resin dispersion having an average particle diameter of 90 nm (minimum value of 50 nm) measured by the dynamic light scattering method by the same procedure except that the emulsion (a6) shown in Table 1 is added dropwise to 2 parts. (A6) was obtained.

ＭＭＡ：メタクリル酸メチル
ＢＡ：アクリル酸ブチル
ＤＡＡＭ：ジアセトンアクリルアミド
ＡＡ：アクリル酸
ＫＨ１０：第一工業製薬製反応型アニオン性界面活性剤
ＮＦ０８：第一工業製薬製非反応型アニオン性界面活性剤

MMA: Methyl methacrylate BA: Butyl acrylate DAAM: Diacetone acrylamide AA: Acrylic acid KH10: Daiichi Kogyo Seiyaku Reactive anionic surfactant NF08: Daiichi Kogyo Seiyaku non-reactive anionic surfactant

(Examples 1-5 and Comparative Examples 1-5)
The aqueous resin dispersions (A1 to A6) obtained above were used as a hydrazide group-containing chemical substance (B), adipic acid dihydrazide, and as a thickener, Natrosol (manufactured by Hercules Incorporated; hydroxyethyl cellulose-based thickener). ) Was dissolved in hot water at 60 ° C., the cooled one was added, and the mixture was stirred with a stirrer for 10 minutes. Thereafter, while stirring, activated carbon (C1 to C2) and Neugen EA-157 (polyoxyethylene styrenated phenyl ether manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) were added as a surfactant for dispersion. Further, as a viscosity adjustment, Primal RM8 ( After adding Proxel AM (Arch Chemicals Japan Co., Ltd.) as a preservative and a urethane associative thickener (Rohm and Haas Company), each aqueous coating composition was obtained by stirring for 20 minutes. Detailed blending ratios and evaluation results are shown in Table 2.

  Activated carbon (C1) is vegetable activated carbon, average pore diameter 20 nm, particle size 3 μm, firing temperature 1000 ° C., activated carbon (C2) is vegetable activated carbon, average pore diameter 35 nm, particle size 5 μm, fired The temperature is 1000 ° C. These average pore diameters were measured with a high-speed specific surface area / pore distribution measuring device ASAP 2405 manufactured by Micromeritics. The particle size is classified by a sieve.

  The evaluation method was performed as follows.

<Storage stability>
Store the water-based paint composition in a thermostat at 50 ° C for one month, and check the viscosity and appearance of the paint. The paint viscosity was measured using a Stormer viscometer.
Evaluation criteria ○: The viscosity measured by a Stormer viscometer is an initial value ± 5 KU, and precipitation or the like is not confirmed.
Δ: Precipitation, aggregation or the like is not confirmed, but when the viscosity measured by a Stormer viscometer is larger than the initial value ± 5, x: Precipitation, aggregation or the like is confirmed

<Film forming properties>
The aqueous coating composition was coated on a slate plate with a 6 mil applicator and dried in a room at 23 ° C. for 1 week, and then the appearance was confirmed.
Evaluation criteria ○: No cracks or the like are confirmed.
Δ: Minute cracks that cannot be confirmed with the naked eye are locally generated.
X: A minute crack is confirmed on the entire surface with the naked eye.

<Background followability>
A tensile test in an atmosphere at 23 ° C. was performed as a base followability test. The test method was based on JIS A6909 and produced the dumbbell-type test piece with a film thickness of 0.2 mm. It was measured using Shimadzu Autograph AG-I 100 kN.
Evaluation criteria ○: 300% or more Δ; 100% or more, less than 300% ×; less than 100%

<Wash resistance>
After coating with a 6 mil applicator on a slate plate, it was dried at 23 ° C. for 1 week to obtain a test piece. The test piece was set in a cleaning tester according to JIS A6909, and the surface was rubbed while applying a load of about 450 gf to the brush. After reciprocating the brush 500 times, the test piece is washed with water, and the portion rubbed with the brush is visually observed for surface peeling and substrate exposure due to wear.
Evaluation criteria: No peeling or substrate exposure on the coating film surface.
Δ: Some peeling on the surface of the coating film and exposure of the substrate.
X: 50% or more of the coating film is exposed by peeling or abrasion.

<Adsorption of pollutants>
-Adjustment of test gas Using a test gas adjustment Tedlar bag, acetaldehyde standard gas (gas concentration 6,000 ppm) is diluted with ordinary air to 3 L (gas concentration 80 to 100 ppm). Thereafter, the minicock is closed, and in order to make the acetaldehyde concentration in the bag more uniform, both ends of the bag are alternately pushed to mix the gas inside, and then left to stand.
-Preparation of test plate An aqueous coating composition was applied twice on a slate plate having an area of 10 x 10 cm with an application amount of 1.5 g with an interval of 1 hour, and dried for 1 week in a desiccator containing silica gel. .
Test operation A cut was made on each side of the evaluation tedlar bag, the test plate produced above was inserted from there, the air in the bag was discharged as much as possible, and the opening was sealed with a heat seal device. Thereafter, the Tedlar bag with adjusted test gas is connected with a silicone tube, and after opening the cocks of both bags, the bag with adjusted test gas is pressed by hand and the test gas is fed into the bag containing the test piece. Thereafter, the cock was quickly closed and allowed to stand in a room at room temperature of 23 ° C. for 30 minutes, and then the acetaldehyde concentration was measured twice using a detector tube, and the average value was taken as the initial value. However, when any of the initial values was out of the range of 80 to 100 ppm, the test gas was adjusted again.

Then, after leaving still for 3 days, it measured using the acetaldehyde density | concentration detection tube again, and pollutant adsorption property was determined using the measured value.
Evaluation criteria ○: Acetaldehyde concentration is less than 10 ppm Δ: Acetaldehyde concentration is 10 ppm or more and less than 30 ppm ×: Acetaldehyde concentration is 30 ppm or more

Claims (4)

A surfactant that can be copolymerized with an α, β-ethylenically unsaturated monomer and an ethylenically unsaturated monomer having a carboxyl group and an ethylenically unsaturated monomer having a carbonyl group excluding the carboxyl group are essential components. Aqueous coating composition comprising an aqueous resin dispersion (A) copolymerized with 0.5 to 10% by weight of a monomer, a compound (B) having two or more hydrazide groups in the molecule, and activated carbon (C) Because
An aqueous coating composition, wherein an average particle diameter of the aqueous dispersion measured by a dynamic light scattering method is larger than an average pore diameter of the activated carbon.   The surfactant used for the aqueous resin dispersion (A) does not include a non-reactive surfactant that does not have a copolymerizability with an α, β-ethylenically unsaturated monomer. The aqueous coating composition as described.   The total amount of surfactants used for dispersing activated carbon and colored pigments and additives such as antifoaming agents and preservatives is 3 parts by mass or less with respect to 100 parts by mass of the coating composition. The water-based paint composition according to claim 1 or 2.   The aqueous coating composition according to any one of claims 1 to 3, wherein the activated carbon (C) has a particle size of 0.1 to 10 µm and is fired at a temperature of 1000 to 1200 ° C.