JP2008285528A - Water-based coating composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-based coating composition stably keeping excellent aldehyde adsorbing property for a long time, available at low cost, harmless to a human body and the environment and having good water resistance and shape retaining property. <P>SOLUTION: Aminoguanidine bicarbonate among guanidine salts is added to a water-based coating composition containing an acrylic resin and water. A coating film and a building material having the coating film is produced by using the water-based coating composition. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is a water-based paint that is suitable for decorative coating of interiors and exteriors such as interior and exterior walls and ceilings of various buildings, and has excellent aldehyde adsorption ability while satisfying various paint performances and coating film properties required as water-based paints. Relates to the composition. Furthermore, this invention relates to the coating material formed by apply | coating the said water-based coating composition, especially a building material.

  Emulsion paints containing acrylic resins are water-based paints that do not use organic solvents, and are gentle paints that do not release environmental hormone substances that adversely affect the environment and the human body. Therefore, interior and exterior walls and ceilings of various buildings Or it is widely used for the exterior etc.

  In particular, finishing methods for indoor wall surfaces in recent residential constructions are often achieved by applying PVC cloth or synthetic resin emulsion coating, but adverse effects due to chemical substances such as chemical hypersensitivity and sick house syndrome are problematic. Natural materials such as plaster without such adverse effects have been reviewed again.

  For example, in Patent Document 1, slaked lime, which is a component of a stucco wall material, is used as a main component, and the formed coating film has a peculiar texture to the stucco wall and the physical properties and conditions of the coating film including alkali resistance and cleaning resistance. A coating composition containing slaked lime, acrylic resin, titanium oxide and water in a predetermined amount has been proposed in order to provide a water-based coating having excellent coating film functions such as moisture, mildew resistance and fire resistance.

  Further, for example, in Patent Document 2, it is possible to make the emission of volatile organic compounds from the coating film into the room as much as possible, and harmful chemicals such as formaldehyde and hydrogen sulfide that are emitted into the indoor environment. A porous additive having a physical adsorption ability such as activated carbon, silica, aluminum silicate, diatomaceous earth, phosphoric acid system, for the purpose of providing a highly functional indoor environment compatible aqueous coating composition capable of adsorbing and decomposing substances It has been proposed to use an additive having a chemical adsorption ability such as a compound or an amine compound, or an additive capable of decomposing a harmful chemical substance by photocatalytic activity such as titanium dioxide or zinc oxide.

Furthermore, Patent Document 3 contains at least an aminoguanidine salt and water with the intention of providing an aldehyde catcher agent that can efficiently capture and detoxify aldehydes such as formaldehyde and acetaldehyde even at low indoor concentrations. An aldehyde catcher agent characterized by the above has been proposed.
Japanese Patent No. 3094227 JP 2002-173645 A JP 2005-97340 A

  In the plaster paint obtained by converting the calcium hydroxide described in Patent Document 1 into a paint, it is said that formaldehyde and calcium hydroxide can be detoxified by a formose reaction, but the effect is not always sufficient. is not. Even if it is assumed that the formose reaction is significant, it is considered that when the plaster paint is dried, calcium hydroxide is carbonated by carbon dioxide in the air, and the formaldehyde resolution decreases with time.

  In addition, none of the paints added with catalysts such as titanium dioxide and zinc oxide proposed in the above-mentioned Patent Document 2 are very expensive and generally used widely. Since it reacts with other components, it is necessary to use other additives in order to suppress this, and the coating becomes complicated. Regarding diatomaceous earth, although it has a high formaldehyde adsorption capacity, it is considered that it should not be actively used because it has a possibility of becoming a second asbestos because of its carcinogenicity recently suggested by its crystal form.

  Furthermore, regarding diatomaceous earth and zeolite, although formaldehyde is physically adsorbed, it does not have a function of chemically adsorbing and decomposing formaldehyde, and in some cases, there is a concern that formaldehyde may be re-released. Long-term aldehyde adsorption ability cannot be expected.

  Moreover, in the said patent document 3, since an aminoguanidine salt is water-soluble, even if it does not use an organic solvent, an aldehyde catcher agent containing an aminoguanidine salt and water is used as a wooden building material, an inorganic building material, paper, cloth, It is described that it can be applied to resin, impregnated, mixed, and dispersed, but when an aldehyde catcher agent is added to a paint to form a coating film, the aminoguanidine salt is There is a problem that it melts and is inferior in film formability and shape maintenance (durability).

  Therefore, an object of the present invention is to provide an aqueous coating composition that has excellent aldehyde adsorption ability stably for as long as possible, is inexpensive and harmless to the human body and the environment, and has good film formability, water resistance and shape maintenance. It is to provide.

  In order to solve the above problems, the present invention provides an aqueous coating composition characterized by containing aminoguanidine bicarbonate, an acrylic resin and water. That is, the present invention is characterized in that aminoguanidine bicarbonate of the conventionally known guanidine salts is used in an aqueous coating composition.

  According to such a configuration, aminoguanidine bicarbonate has a plurality of functional groups capable of reacting with aldehydes, and also exhibits high reactivity with aldehydes such as acetaldehyde in which an electron donating group is bonded to carbonyl carbon. Even in the concentration range (for example, about 0.01 to 0.1 ppm), aldehyde can be efficiently captured.

  In addition, since aminoguanidine bicarbonate is sparingly soluble in water, it does not deteriorate the water resistance of the coating film even after the aldehyde is captured in the aqueous coating composition or the coating film formed from the aqueous coating composition. The film property and the shape maintaining property can be imparted more reliably. In addition, since aminoguanidine bicarbonate is a white solid, it can also contribute to the hiding power required for paints.

  The aqueous coating composition of the present invention can exhibit the above desired effect as long as it contains aminoguanidine bicarbonate, and the content (lower limit) of aminoguanidine bicarbonate is not particularly limited. However, it is preferable that it is 0.01 weight% or more in conversion of solid content. If it is 0.01 weight% or more, aldehyde adsorption ability can be obtained more reliably. Furthermore, the content (lower limit) of aminoguanidine bicarbonate is particularly preferably 0.05% by weight or more, particularly 0.25% by weight or more in terms of solid content. If it is these ranges, the further outstanding aldehyde adsorption ability can be exhibited over a long period of time.

  In addition, since the water-based coating composition of the present invention has a higher aldehyde adsorption ability for a longer period as the content of aminoguanidine bicarbonate is higher, the above-described heavy-duty coating composition is within the range that does not adversely affect film-forming properties and water resistance. Although there is no restriction | limiting in particular in content (upper limit) of aminoguanidine carbonate, It is preferable that it is 30.0 weight% or less in conversion of solid content. If it is 30.0% by weight or less, an excellent aldehyde adsorbing ability can be reliably obtained over a long period of time without using extra aminoguanidine bicarbonate. Furthermore, it is particularly preferable that the content (upper limit value) of aminoguanidine bicarbonate is 1.0% by weight or less, particularly 0.5% by weight or less in terms of solid content. Within these ranges, the aldehyde adsorption ability obtained by adding the aminoguanidine bicarbonate can be exerted almost maximally without using extra aminoguanidine bicarbonate.

  When preparing the aqueous coating composition of the present invention, an emulsion can be suitably used as the mixture of the acrylic resin and water. Therefore, the acrylic resin content may vary depending on the type and specification of the available emulsion, and may be, for example, 2 to 45% by weight in terms of solid content.

  The present invention also relates to a coating film characterized by being formed from the above-described aqueous coating composition of the present invention. As described above, aminoguanidine bicarbonate contained in the aqueous coating composition of the present invention is hardly soluble in water because it is poorly soluble in water. Therefore, the coating film of the present invention is excellent in water resistance and particularly has a shape maintaining property. It can be maintained more reliably.

  Furthermore, this invention also provides the building material characterized by having a base material and the said coating film provided in at least one part of the surface of the said base material. Examples of such building materials include various interior and exterior building materials (boards, panels, cloths, etc.) used as inner and outer wall materials and ceiling materials, and the above-described aqueous coating composition of the present invention is used. Since the formed coating film of the present invention is provided, the effect of being excellent in water resistance and weather resistance is exhibited.

  According to the present invention, aldehyde adsorption ability is stable over a long period of time, is inexpensive, hardly induces chemical hypersensitivity, sick house syndrome, etc., is harmless to the human body and the environment, and has good water resistance and shape maintenance after formation. A water-based coating composition capable of realizing a coating film having the above can be obtained.

  The aqueous coating composition of the present invention is a coating composition containing aminoguanidine bicarbonate, an acrylic resin and water as main components. In order to solve the above-mentioned problems, the present inventor has conducted intensive experiments on the use of a number of compounds known to have aldehyde adsorption ability in an aqueous coating composition.

  According to the disclosure of Patent Document 3, it is important that the compound having an aldehyde adsorption ability has a functional group capable of reacting with an aldehyde. However, the object of the present invention is to obtain a water-based paint composition that is friendly to the human body and the environment. Stability, aldehyde adsorption ability, etc. in a product are important, and it is not always necessary to have an amino group that can react with an aldehyde.

  Therefore, as a result of conducting extensive studies as described above, the present inventor has focused on guanidine salts having excellent aldehyde adsorption ability, and among them, aminoguanidine bicarbonate is excellent in poor water solubility. In addition, the specific function of the water-based paint composition using the acrylic resin emulsion is not deteriorated. In other words, it has the same quality and feeling as those of the conventional acrylic resin emulsion paint, and a coating film with excellent water resistance can be obtained. As a result, the present invention has been completed.

  In the aqueous coating composition of the present invention, as described above, aminoguanidine bicarbonate has a plurality of functional groups capable of reacting with aldehydes, and is also high with aldehydes such as acetaldehyde in which an electron donating group is bonded to carbonyl carbon. Since it shows reactivity, aldehyde can be efficiently captured even in a low concentration region (for example, about 0.01 to 0.1 ppm).

  That is, the present inventor blended aminoguanidine bicarbonate with an emulsion containing an acrylic resin and water, so that the storage stability, coating workability and film formability can be improved without impairing the texture and function of the conventional acrylic resin emulsion paint. It has been found that an aqueous coating composition can be prepared which can realize a coating film having an excellent aldehyde adsorption ability, water resistance and shape maintenance.

  Furthermore, the present inventor can conceal the construction surface (surface to be coated) with a very small amount of coating and is excellent in film formability by using the aqueous coating composition of the present invention as described above. In addition, the formed coating film can exhibit sufficient adhesion and toughness, and also has excellent leveling properties, making it possible to make a thin coating film with a smaller coating amount, such as brushes, rollers, sprays, etc. It has been found that the coating film can be easily and beautifully finished by the conventionally known painting means.

Here, the aminoguanidine bicarbonate used in the present invention is a white crystalline granular powder represented by the chemical formula: [NH ₂ C (NH) NHNH ₂ ] H ₂ CO ₃ . As described above, this aminoguanidine bicarbonate has a high reactivity with aldehydes such as acetaldehyde, which has multiple functional groups capable of reacting with aldehydes, and an electron donating group is bonded to the carbonyl carbon. Can be captured. In addition, since the functional group portion chemically bonds with the aldehyde, the aldehyde is chemically adsorbed, so that the aldehyde adsorption ability can be exhibited over a long period of time.

In addition, since aminoguanidine bicarbonate is sparingly soluble in water, the shape can be obtained without reducing the water resistance of the coating film even after the aldehyde is captured in the aqueous coating composition or the coating film formed from the aqueous coating composition. The maintainability can be more reliably exhibited, and the hiding power required for the paint can also be exhibited. In addition, aminoguanidine bicarbonate has the following properties, for example.
Molecular weight: 136.1
Solubility: 0.05g / 100g · aq or less (20 ° C)
Melting point: about 170 ° C
LD50: 1160 mg / kg (ipr-rat)

  The acrylic resin used in the present invention is a monomer comprising at least one acrylic monomer selected from the group consisting of (meth) acrylic acid, (meth) acrylic acid ester, (meth) acrylamides, and (meth) acrylonitrile. Examples include polymers (homopolymers or copolymers) that are included as components. Although there will be no restriction | limiting in particular if it is the said monomer component, For example, the monomer components of the following (i)-(iv) are mentioned.

(i) Acrylic acid and methacrylic acid.

(ii) Acrylic acid ester or methacrylic acid ester: for example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, hexyl acrylate, Acrylic acid alkyl ester having 1 to 18 carbon atoms of alkyl group such as n-octyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate, palmityl acrylate or cyclohexyl acrylate; methyl methacrylate, methacryl Ethyl acetate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, hexyl methacrylate, n-octyl methacrylate, 2-ethyl methacrylate Alkyl methacrylates having about 1 to 18 carbon atoms of alkyl groups such as xylyl, lauryl methacrylate, stearyl methacrylate, palmityl methacrylate and cyclohexyl methacrylate; hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, Alkyl esters having a hydroxyl group in the side chain of (meth) acrylic acid such as hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate; methoxybutyl acrylate, methoxybutyl methacrylate, methoxyethyl acrylate, methoxyethyl methacrylate Alkyl esters having an alkoxyl group in the side chain of (meth) acrylic acid such as ethoxybutyl acrylate and ethoxybutyl methacrylate; allyl acrylate and methacrylate Alkenyl esters of (meth) acrylic acid such as allyl acrylate; alkenyloxyalkyl esters of (meth) acrylic acid such as allyloxyethyl acrylate and allyloxyethyl methacrylate; glycidyl acrylate, glycidyl methacrylate, and methyl glycidyl acrylate Alkyl ester having an epoxy group in the side chain of acrylic acid such as methyl glycidyl methacrylate; mono- (meth) acrylic acid such as diethylaminoethyl acrylate, diethylaminoethyl methacrylate, methylaminoethyl acrylate, methylaminoethyl methacrylate, etc. Or a di-alkylaminoalkyl ester; (meth) acrylic acid ester having a silane group or an alkoxysilane group as a side chain.

(iii) Acrylamides or methacrylamides: for example, acrylamide; methacrylamide; (meth) acrylamide having a methylol group such as N-methylolacrylamide and N-methylolmethacrylamide; N-alkoxymethylolacrylamide (for example, N-isobutoxymethylol) (Meth) acrylamide having an alkoxymethylol group such as N-alkoxymethylol methacrylamide (for example, N-isobutoxymethylol methacrylamide); having an alkoxyalkyl group such as N-butoxymethyl (meth) acrylamide. (Mono) acrylamide etc.

(Iv) Various acrylic monomers such as acrylonitrile and methacrylonitrile.

  These acrylic monomers can be used alone or in admixture of two or more. That is, the acrylic resin used in the present invention may be, for example, a homopolymer composed of one of the above monomer components or a copolymer composed of any combination of two or more. A polymer (homopolymer or copolymer) having (meth) acrylic acid or an ester thereof as a monomer unit is preferable. As long as the effects of the present invention are not impaired, for example, up to about 30% of the monomer component, for example, the use of vinyl monomers other than the above acrylic monomers such as styrene and vinyl acetate is not prevented.

  The type of acrylic monomer, the amount used, the degree of polymerization, etc. can be obtained, for example, by taking into consideration the use temperature (curing temperature) of the aqueous coating composition of the present invention and the compatibility with other components of the aqueous coating composition. The glass transition point (Tg) and the like are appropriately selected. For example, the acrylic resin used when the aqueous coating composition is prepared as a room temperature drying type coating is not particularly limited, but may be selected such that the glass transition point is about -80 ° C to 20 ° C. preferable. A glass transition point of preferably −40 ° C. to 10 ° C., more preferably −20 ° C. to 5 ° C. can be selected.

  In addition, the acrylic resin used when the aqueous paint composition is prepared as a forced drying paint (for example, drying temperature: 50 ° C. to 200 ° C.) is not particularly limited, but the glass transition point is in the range of 20 ° C. to 100 ° C. It is preferable to select such that

  When the aqueous coating composition of the present invention is prepared in a mode that is easily used for on-site coating construction, the aqueous coating composition is preferably a room-temperature-drying paint that can be cured at room temperature to room temperature. It is preferable that the acrylic resin used for is also a room temperature dry resin.

  The form of the acrylic resin that can be used in the present invention is not particularly limited, and is an aqueous emulsion or dispersion form such as an emulsion or an aqueous polymer dispersion, a powder form such as a re-emulsified powder resin, a liquid form such as a liquid polymer, etc. Either form may be sufficient. Preferably, it is in the form of an emulsion. When blended as an emulsion, the emulsion may be obtained by emulsion polymerization of a monomer having a polymerizable unsaturated double bond, or may be obtained by dispersing a previously synthesized resin in an aqueous dispersion medium using a dispersant. Further, a powder type polymer prepared by dispersing in water or the like can be mentioned.

  The acrylic resin used in the present invention is composed of aminoguanidine bicarbonate in an aqueous coating composition and the adhesive strength between various additives described later, film formability of a coating film formed from the aqueous coating composition, shape maintenance and durability. And the adhesive strength between the aqueous coating composition and the object to be coated are increased. And it has the function which prevents the crack of the coating film (coating layer) formed in the to-be-coated object surface, and improves the toughness of building materials.

  The mixing ratio of the acrylic resin is not particularly limited as long as it does not impair the effects of the present invention, but performance required as a water-based paint such as storage stability, coating workability and film formability, preferably JIS K described later. It is preferably within a range satisfying the properties of at least two types of paints defined in 5663-1955, and can be appropriately determined according to the type of acrylic resin used. Specifically, 2 to 45% by weight in terms of solid content may be an acrylic resin in the aqueous coating composition of the present invention. Preferably it is 5 to 30 weight%, More preferably, it is 8 to 15 weight%.

  In the present invention, in addition to the aminoguanidine bicarbonate and acrylic resin, pigments (white pigments, colored pigments, extender pigments) and various additives can be added alone or in appropriate combination. Examples of such additives include pigment dispersants, wetting agents, antifoaming agents, thickeners, freeze / thaw stabilizers, film forming aids such as film forming aids and rheology modifiers, and inorganic materials (fine bones). Inorganic fillers such as materials), surfactants, plasticizers, water reducing agents, fluidizing agents, preservatives and antibacterial agents.

  The pigment is not particularly limited as long as it is used in water-based paints, and any pigment can be adopted, but an inorganic pigment is preferable. Examples of such inorganic pigments include white pigments such as titanium oxide, zinc white, lithopone, zinc sulfide, and antimony white; black pigments such as carbon black and iron oxide; cadmium red, red rose (iron oxide), molybdenum red, and red lead. Red pigments: Yellow pigments such as chrome yellow, titanium yellow, cadmium yellow, yellow iron oxide, antimony yellow, vanadium tin yellow, vanadium zirconium yellow, etc .; chromium oxide, viridian, titanium cobalt green, cobalt green, cobalt chrome green Green pigments such as Victoria Green; various colored pigments such as ultramarine blue, bituminous blue, cobalt blue, cerulean blue, cobalt silica blue, cobalt zinc silica blue, etc .; talc, kaolin clay, aluminum hydroxide, calcium carbonate ( Calcium carbonate, precipitated calcium carbonate), bentonite, barium (precipitated barium sulfate, barite powder) include extender pigments such as white carbon, silica.

  Further, as extender pigments, for example, inorganic aggregates (fine aggregates) such as quartz sand, cold water sand, perlite, vermiculite, shirasu spheres and sludge fired aggregates, kaolin, halloysite, montmorillonite, bentonite, gibbsite , Mica, ceramic sand, glass beads, perlite, acid clay, porcelain stones, wax stone, feldspar, limestone, plaster, dolomite, magnesite, talc, etc .; calcium hydroxide (slaked lime), barium hydroxide, water Water-insoluble metal hydroxides such as magnesium oxide and natural calcium; calcium silicate hydrates such as tobermonite and zonotolite; hydrates of various oxides such as calcium aluminate hydrate and calcium sulfoaluminate hydrate Alumina, silica, hydrous silicic acid, magnesia, zinc oxide, spinel, Forming calcium carbonate, calcium phosphate, magnesium carbonate, barium sulfate, powdered and synthetic minerals, such as potassium titanate, and the like fibrous or particulate inorganic materials.

  The ratio of the pigment to be blended in the aqueous coating composition of the present invention is not particularly limited as long as the effects of the present invention are not impaired, and the desired hiding power and color (lightness, chromaticity, chroma) are desired. It can be appropriately selected and adjusted accordingly.

  Among the above pigments, white pigments such as titanium oxide can be exemplified. Titanium oxide includes rutile type, anatase type and brookite type, and any of them can be used. In general, the rutile type has better light resistance and hiding power than the anatase type. The particle size and shape are not particularly limited, and can be appropriately selected from commercially available products according to the purpose. For example, there are substantially spherical titanium oxide having a particle size of 0.1 to 0.5 μm, ultrafine titanium oxide of 0.01 to 0.05 μm, and plate-like titanium oxide for absorbing ultraviolet rays.

  From the viewpoint of hiding power, rutile titanium oxide is preferably used, and titanium oxide having a particle size of 0.1 to 0.3 μm can be suitably used. In order to improve the hiding power, an extender pigment can be further used in combination, and calcium carbonate can be preferably mentioned as such an extender pigment.

  For example, the blending ratio when using titanium oxide may be 10 to 30% by weight in terms of solid content in the aqueous coating composition. Preferably it is 13 to 25 weight%, More preferably, it is 16 to 20 weight%. By blending titanium oxide in the above proportion in the water-based coating composition of the present invention, the coated surface can be concealed with a smaller coating amount, and the desired appearance and physical properties are formed despite the thin coating film formed. Have

  Although it does not restrict | limit especially as said pigment and an inorganic material, For example, what has a particle size of the range of 60-130 mesh or 80-100 mesh is mentioned. Moreover, the ratio in the case of mix | blending inorganic fillers, such as an inorganic fine aggregate, with the water-based coating composition of this invention can be suitably set in the range which does not impair the effect of this invention. A fibrous filler or the like may be included in the aqueous coating composition of the present invention as long as it does not affect the coating workability, the film forming property, and the appearance of the coating film.

  As the dispersing agent and wetting agent, conventionally known ones can be used. For example, polycarboxylic acid sodium salt, formalin condensate of sodium alkylnaphthalene sulfonate, low molecular weight ammonium polyacrylate, low molecular weight styrene-maleic acid Examples thereof include ammonium salts of copolymers, fatty acid esters of polyoxyethylene, alkylphenol ethers, sulfosuccinic acid derivatives, block polymers of polyethylene oxide and polypropylene oxide, and the like. These blending ratios can also be set as appropriate within a range not impairing the effects of the present invention.

  As the antifoaming agent, conventionally known antifoaming agents can be used. For example, various mineral oil-based compounds, octyl alcohol, glycol derivatives, cyclohexane, silicon, pluronic surfactants, polyoxyethylene alkylphenyl ether, and the like. Examples include foam suppressors and foam breakers. These blending ratios can also be appropriately selected and are not limited, and can be appropriately set within a range not impairing the effects of the present invention.

  Examples of the thickener include cellulose type such as cellulose ether, methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl methyl cellulose; polysaccharides such as saccharose and glucose; acrylic type; others, aluminum stearate, zinc stearate, organic bentonite, silica gel, polyvinyl Alcohol, sodium alginate, silicic acid type, montmorillonite, bentonite, sodium caseinate and the like can be mentioned.

  The aqueous coating composition of the present invention having the composition as described above is mixed with a conventionally known apparatus such as a paint blending device (mixer, shaker, mill, kneader, etc.), for example, to obtain aminoguanidine bicarbonate, It can be obtained by stably dispersing the acrylic resin and various additives and pigments added as necessary in water. And it can prepare as a coating material which has various forms, such as a spray liquid, a slurry, or a putty. Although the atmospheric temperature at the time of mixing is not specifically limited, Usually, it can carry out at 20-95 degreeC.

  For example, according to various coating methods such as spray coating (air spray, airless spray, etc.), brush coating, roller coating, putty coating, coat coating (curtain flow coater, roll coater, etc.), the aqueous coating composition of the present invention is used. Can be prepared to have the desired viscosity. For example, a preferable viscosity range can be appropriately selected and prepared in consideration of coating workability, leveling, coating film appearance, and the like.

  The aqueous coating composition of the present invention is usually prepared to have a viscosity range of 100 to 150,000 mPa · s at room temperature (25 ± 5 ° C.), for example. In particular, the viscosity of a liquid (low viscosity) aqueous coating composition (low viscosity product) may be, for example, in the range of 300 to 3000 mPa · s at room temperature, for example, when applied by brush, roller or spray. The viscosity of the high-viscosity aqueous coating composition (high-viscosity product) may be, for example, in the range of 100,000 to 130,000 mPa · s at room temperature, for example, when applying a iron.

  In addition, the water-based paint composition of the present invention is used for coating interior and exterior surfaces such as ceilings and walls (inner / outer walls) of various buildings, and a base material for ceilings and walls (inner / outer walls) of buildings. And various building materials (cloth, panels, boards, etc.) used as decorative materials. In addition, after the aqueous coating composition of the present invention is applied by a conventionally known method as described above, it is further patterned by performing patterning with a concavo-convex patterning roller or treating the surface of the coating film. You can also

  The water-based coating composition of the present invention preferably relates to at least two kinds of paints defined in JIS K 5663-1995 in the properties of the coating liquid and the appearance and physical properties of the dried coating film. To satisfy the requirements of (2) coating workability, (3) low temperature stability, (4) appearance of coating film, (5) alkali resistance, (6) washing resistance and (7) concealment rate It is preferable to prepare.

  Furthermore, the water-based coating composition of the present invention has no abnormality even when immersed in deionized water for 96 hours (JIS K 5663-5.9 5.9) with respect to water resistance (JIS K 5400 8.19), and accelerated weather resistance. With regard to the property (JIS K 5400 9.8.1), the chalking degree is 8 points or more, there is no swelling, peeling or cracking, and the degree of color change is not as great as that of the sample (JIS K 5663- 1995, 5.12), and the concealment rate satisfies 0.93 or higher (JIS K 5663-1995 5.8), and further the weather resistance (JIS K 5400 9.9) is a 12 month test. It is preferable to satisfy the requirement that there is no swelling, peeling or cracking after the period, and the degree of color change and chalkiness are not large compared to the sample (5.13 of JIS K 5663-1995).

  The drying time in the case of applying the aqueous coating composition of the present invention can be changed by appropriately adjusting the composition (type of components, solid content and water content, etc.), viscosity, etc., and is particularly limited. Although it is not a thing, when it implements according to the test method of 6.5 of JIS K 5400 according to 5.6 of JIS K 5663-1995, it will be in a semi-hardened state within 2 hours at 20 ° C. Moreover, it is preferable to prepare so that it may become a semi-hardened state within 4 hours at 5 degreeC.

The present invention also relates to a coating film formed from the aqueous coating composition of the present invention as described above. The coating film of the present invention is a water-based coating composition of the present invention as described above. In the case of a low-viscosity product, for example, at least 50 g in terms of solid content per 1 m ² area of the substrate (coating object), preferably It can be formed by using about 150 g. In the case of a high-viscosity product, for example, it can be formed by using at least 500 g, preferably about 750 g in terms of solid content, per 1 m ^{2 of the} substrate (object to be coated). Since the function of the coating film of the present invention is improved as the coating amount of the aqueous coating composition, particularly the amount of aminoguanidine bicarbonate and acrylic resin increases, the upper limit of the coating amount is not limited. In consideration of film properties and shape maintenance, cost, coating workability, etc., the water-based coating composition of the present invention is in the range of 50 g to 300 g in terms of solid content in the case of a low-viscosity product per 1 m ² of the area to be coated. In the case of a high-viscosity product, it is preferably used in the range of 500 g to 1000 g in terms of solid content.

  Further, the thickness of the coating film of the present invention is not particularly limited, and may be any thickness as long as the coated surface of the base material is sufficiently concealed in the building material of the present invention. The aqueous coating composition of the present invention can be prepared so that the coating hiding power is 500 μm or less, preferably 300 μm or less, more preferably 200 μm or less, and even more preferably 100 μm or less. The thickness is at least 500 μm, preferably at least 300 μm, more preferably at least 200 μm, and even more preferably at least 100 μm. In view of the physical properties and functions of the coating film such as cost, coating workability and film formability, it is usually 10 It may be in the range of ˜300 μm, preferably 20 to 250 μm, more preferably 30 to 200 μm, still more preferably 50 to 150 μm. However, it is preferable that the coating film is thick from the viewpoint of aldehyde adsorption capacity, and it is possible to form a thicker coating film using the aqueous coating composition of the present invention.

  Furthermore, this invention relates also to the building material which comprises a base material (to-be-coated object) and the coating film of this invention provided in at least one part of the surface of the said base material. Such a base material is not particularly limited, and examples thereof include various materials used as a base material or a decorative material for a ceiling or wall (inner / outer wall) of a building, such as a cloth, a board, and a panel. . In addition, you may perform various processes, such as a sealer process, on the surface of the said base material.

  Examples of the cloth include a wide range of cloth materials used for, for example, architectural interiors (such as indoor walls and ceilings). Examples of the cloth material include paper and a fibrous sheet such as a nonwoven fabric or a woven fabric made of various fibers. The paper may be any of Japanese paper, Western paper (high quality paper and medium quality paper), kraft paper, thin paper, backing paper, resin impregnated paper, cardboard, cardboard, etc. Also included are flame-retardant backing paper and non-combustible paper suitable for wallpaper construction. Examples of the fibrous sheet include natural woven fabrics; glass fibers; or porous woven fabrics and nonwoven fabrics obtained from synthetic fibers such as polypropylene, acrylic, nylon, polyester, polyamide, and vinylon, and knitted fabrics. . In addition, the base material in the building material of this invention may be single 1 type, or 2 or more types of arbitrary combinations (for example, laminated body etc.).

  Examples of the board and panel include board materials and panel materials used for interiors for buildings (such as indoor walls and ceilings) and exteriors. Wood board, plywood, medium density fiber board, plastic board, cement mortar, concrete board, PC panel, ALC panel, asbestos slate, gypsum board, particle board, foam cement board, wood chip cement board, calcium silicate board and siding board Can be illustrated. Preferably, a gypsum board, a gypsum particle board, a wooden board, a medium density fiber board, a plastic board, a siding board (a metal type and a ceramics type are included), etc. are mentioned.

  The method for producing the building material having the coating film of the present invention by applying the aqueous coating composition of the present invention to these substrates is not particularly limited, and a coating method using a roll coater, a flow coater, a brush, a roller, or the like. And spraying methods using sprays and various guns. For example, according to spray coating using compressed air, first, a spray liquid or slurry of the aqueous coating composition of the present invention having an appropriate viscosity is sprayed on one surface of a substrate. By this spraying, the aqueous coating composition forms a coating film on the surface of the substrate and is integrated with the substrate.

  In this case, more specifically, the acrylic resin component contained in the coating composition strongly binds components such as aminoguanidine bicarbonate, and a coating film precursor (coating before drying) composed of an aqueous coating composition. Is formed on the substrate surface, and the coating film precursor and the substrate are integrated. Next, the coating film precursor applied to the substrate is dried and cured. Such a method can be carried out easily and simply by applying an aqueous coating composition to a substrate and then performing natural drying, ventilation drying or forced drying.

  The coating film and building material of the present invention do not cause inconveniences such as blown unevenness, uneven color, and uneven luster against various kinds of light such as direct sunlight, oblique light, illumination, and shadow, and always has a constant color, gloss, and texture. Because it has the appearance it has, it is useful for inner and outer wall materials and ceiling materials. In general, in the case of building materials such as boards (panels) and cloths, the processing of joints and joints between building materials after construction is a problem, but the aqueous coating composition of the present invention (especially not including fibrous fillers) (especially According to the coating film and building material obtained by using the case where the fibrous filler or the like is not included, the surrounding coating film is formed by polishing the joint surface of the building material or the coating surface of the joint after construction on the wall or the like. It can be finished continuously and uniformly so that it is almost indistinguishable from the layer.

  Moreover, according to the building material having a coating film obtained by applying the aqueous coating composition of the present invention (especially when it does not include a fibrous filler or the like), it is easy and simple to repair after being applied to a wall or the like. Can be done. That is, when a building material is scratched or soiled after construction, only the damaged portion can be partially repaired using the aqueous coating composition of the present invention. This repair is performed, for example, by shaving the damaged part, filling the part with the aqueous coating composition of the present invention having the same composition as the surrounding coating layer layer and reducing the moisture content to increase the viscosity, and after curing and curing. Accordingly, the surface may be polished. It is also possible to repair and repair the damaged portion so that it cannot be distinguished from other peripheral regions by polishing shear.

  The aqueous coating composition of the present invention can also be suitably used for construction of construction materials (construction of interior and exterior). When the building material of the present invention (especially the interior / exterior panel) is applied to a wall base material with a nail or a screw, a relatively high viscosity book as described above is formed in the nail head recess formed on the surface of the building material. The aqueous coating composition of the present invention (putty) is filled, and if necessary, the aqueous coating composition of the present invention (spray liquid, slurry) is further applied thereon, cured and cured, if necessary. By polishing the surface of the coating film, it can be constructed so that the nailing portion is hardly recognized. According to this, sticking of building materials with an adhesive can be omitted.

  Moreover, the aqueous coating composition of this invention can be used suitably also for the restoration | repair of a building interior / exterior. That is, this invention relates to the restoration method of the construction surface of the building interior / exterior using the said water-based coating composition or building material. For example, when repairing a damaged part of a wall surface having a coating layer formed on the surface by applying the aqueous coating composition of the present invention, the damaged coating layer is scraped off if necessary, and this is applied to the scraped portion. The aqueous coating composition of the invention may be filled or applied and dried, and the coating surface may be polished and ground as necessary.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, these examples are only one aspect of the present invention, and the present invention is not limited thereto.

[Examples 1 to 10 and Comparative Examples 1 to 12]
First, three components shown in the column A of Table 1 were stirred for several minutes with a mixer to obtain a mixture A. Next, three components shown in column B of Table 1 were added to the above mixture A to obtain a mixture B. After increasing the number of revolutions of the mixer, glass beads (Potters Barotini) were added to the mixture B, The particles contained in the mixture B were finely pulverized. After pulverization by stirring with a mixer for about 8 minutes, two components shown in column C of Table 1 were added to the above mixture B to obtain a mixture C, which was stirred for 30 minutes or more. Thereafter, glass beads, bubbles, impurities and the like were removed by filtration to obtain aqueous coating compositions 1 to 10 and comparative aqueous coating compositions 1 to 12 of the present invention.

  However, the amount of each component is adjusted so that the weight ratio (in terms of solid content) of each component in the resulting aqueous coating composition is the value shown in Table 1, and in particular, the content of additive X (in terms of solid content) Was adjusted to the values shown in Table 2.

However, as the additive X, the following were used.
Examples 1 to 10 Aminoguanidine bicarbonate manufactured by Sanwa Chemical Co., Ltd. Comparative Examples 2 to 6 Special grade melamine manufactured by Kishida Chemical Co., Ltd. Comparative Examples 7 to 10 Guanidine carbonate manufactured by Tokyo Chemical Industry Co., Ltd. Comparative Example 11 Primary urea manufactured by Kishida Chemical Co., Ltd. Comparative Example 12 Primary ethylene urea manufactured by Wako Pure Chemical Industries, Ltd.

[Evaluation Test 1]
(1) Formaldehyde adsorption test 1
Formaldehyde (HCHO) adsorption ability of the coating films obtained using the aqueous coating compositions 1 to 10 and the comparative aqueous coating compositions 1 to 12 of the present invention was tested. Each of the aqueous coating compositions 1 to 10 and the comparative aqueous coating compositions 1 to 12 of the present invention was applied on the surface of a glass plate of 50 mm × 50 mm × 1.8 mm (average glass manufactured by Asahi Glass Co., Ltd.) at about 1. Each 0 g was applied with a brush and allowed to dry naturally. Thus, a coating film having a thickness of about 100 μm was produced.

  On the other hand, formalin was previously vaporized in the first tedlar bag (made by DuPont, USA) having a capacity of 5 liters from the previous day. The glass plate provided with the coating film as described above was sealed in a second Tedlar bag (manufactured by DuPont, USA) and air was injected. Next, the formaldehyde vaporized in the first Tedlar bag was sucked with a syringe and injected into the second Tedlar bag.

  And after inject | pouring formaldehyde into the said 2nd Tedlar bag, immediately after injection | pouring, after 1 hour progress and 5 hours progress, a total of 3 times, the gas tech detector tube no. The formaldehyde concentration in the second Tedlar bag was measured using 91 (formaldehyde detector tube).

  Further, the formaldehyde adsorption rate was calculated based on the following formula using the formaldehyde concentration immediately after injection and the formaldehyde concentration after 5 hours. However, the formaldehyde concentration immediately after injection was normalized as 100 and expressed as an index. The results are shown in Table 2.

  From the results shown in Table 2, the coating film obtained using the aqueous coating composition of the present invention has excellent formaldehyde adsorption when the content of aminoguanidine bicarbonate is 0.01% by weight (Example 1) or more. It can be seen that it has the ability. Moreover, the formaldehyde adsorption ability was higher in the example using aminoguanidine bicarbonate than in the comparative example using melamine, guanidine carbonate, urea and ethylene urea.

(2) Formaldehyde adsorption test 2
The formaldehyde adsorbing ability of the coating film obtained using the aqueous coating composition of the present invention having an aminoguanidine bicarbonate content of 1.0% by weight (Example 6) was further measured. Specifically, after 3 days of the test of (1), formaldehyde was further injected, and the formaldehyde concentration in the second Tedlar bag in the same manner as in (1), two times immediately after injection and after 5 hours had elapsed. And the adsorption rate was measured. Thereafter, the same test was conducted every 3 days. Furthermore, here, after measuring 5 hours after each time (1st day, 4th day, 7th day and 10th day), the sample was left for 3 days, and the formaldehyde adsorption rate was measured again.

  From the results shown in Table 3, the formaldehyde adsorption capacity of the coating film produced using the aqueous coating composition having an aminoguanidine bicarbonate content of the present invention of 1.0% by weight (Example 6) Although it decreases, the cumulative total (after 13 days) shows that about 800 times as much formaldehyde as 0.08 ppm, the indoor concentration guideline value established by the Ministry of Health, Labor and Welfare, was adsorbed. From this, it can be said that the coating film of this invention is excellent in the initial formaldehyde adsorption ability, and is excellent also in the durability of formaldehyde adsorption ability.

(3) Formaldehyde adsorption test 3
An aqueous coating composition of the present invention having an aminoguanidine bicarbonate content of 1.0% by weight (Example 6), 10.0% by weight (Example 8) and 20.0% by weight (Example 9); It is obtained using a comparative water-based paint composition having a guanidine carbonate content of 1.0% by weight (Comparative Example 7), 10.0% by weight (Comparative Example 9) and 20.0% by weight (Comparative Example 10). The coating film was examined to determine whether the adsorption rate of formaldehyde decreases with time when it contains moisture.

  Specifically, each of the water-based coating compositions 6, 8 and 9 of the present invention and the comparative water-based coating compositions 7, 9 and 10 is the surface of a slate plate (manufactured by Nozawa Co., Ltd.) of 150 mm × 70 mm × 3 mm. About 3.0 g each was applied with a brush and allowed to dry naturally. Then, the part except the said coating film was sealed using the Epomer P-800 made from Nagase ChemteX Corporation.

  Next, the coated film is allowed to stand in a constant temperature bath at 50 ° C. until it reaches a constant weight. After the constant weight is reached, it is immersed in water for 2 days and left in a constant temperature bath at 50 ° C. until it reaches a constant weight. did. About the coating film before and behind immersion, the formaldehyde density | concentration was measured a total of 3 times, just after injection | pouring, after 1 hour progress and 5 hours progress similarly to said (1), and the adsorption rate after 5 hours was computed. However, the formaldehyde concentration immediately after injection was normalized as 100 and expressed as an index. The results are shown in Table 4.

Moreover, the reduction | decrease rate (%) of the adsorption rate before and behind immersion was computed based on the following numerical formula using the formaldehyde adsorption rate before and behind immersion. The results are shown in Table 4.

  From the results shown in Table 4, it can be seen that the formaldehyde adsorption rate of a coating film obtained using an aqueous coating composition using either aminoguanidine bicarbonate or guanidine carbonate decreases after immersion in water. However, the higher the content of aminoguanidine bicarbonate and guanidine carbonate, the higher the formaldehyde adsorption rate, the lower the adsorption rate reduction rate before and after immersion, and the case where aminoguanidine bicarbonate is used rather than guanidine carbonate, It can be seen that the adsorption rate reduction rate before and after immersion is smaller, and the excellent formaldehyde adsorption rate is maintained over a long period of time.

[Evaluation Test 2]
The content of aminoguanidine bicarbonate was 1.0% by weight (Example 6), 5.0% by weight (Example 7), 10.0% by weight (Example 8) and 20.0% by weight (Example 9). ) Of the present invention, and the content of guanidine carbonate is 1.0% by weight (Comparative Example 7), 5.0% by weight (Comparative Example 8), 10.0% by weight (Comparative Example 9) and The water resistance of the coating film obtained by using 20.0% by weight (Comparative Example 10) of the comparative aqueous coating composition was tested.

  Specifically, each of the aqueous coating compositions 6 to 9 and the comparative aqueous coating compositions 7 to 10 of the present invention is made of a glass plate of 150 mm × 70 mm × 1.8 mm (parallel glass manufactured by Asahi Glass Co., Ltd.). About 3.0 g each was applied to the surface with a brush and allowed to dry naturally. Thus, a coating film having a thickness of about 72 μm was produced. After dropping one drop of water on the coating film thus obtained with a dropper, rubbing the coating film with a black cloth (felt wool solid No. 9 / black, manufactured by Yuzawa Corporation), The degree to which the paint adhered was visually observed.

  As a result, in the coating film of the present invention containing aminoguanidine bicarbonate, the contact angle between the water droplet and the coating film surface was large. In the rubbing test, the paint did not adhere to the black cloth in any of the coating films. On the other hand, in the comparative coating film containing guanidine carbonate, the contact angle between the water droplet and the coating film surface was small. In the rubbing test, the larger the content of guanidine carbonate in the coating film, the greater the amount of paint adhered to the black cloth.

The water-based paint composition of the present invention has a stable aldehyde adsorption ability over a long period of time, is inexpensive and hardly induces chemical sensitivity or sick house syndrome, is harmless to the human body and the environment, has good water resistance and A coating film having shape maintaining property can be realized. Therefore, the water-based coating composition of the present invention can be suitably used for coating films, building materials, construction materials (interior / exterior) construction methods, building materials (interior / exterior) restoration methods, and the like.

Claims (6)

  An aqueous paint composition comprising aminoguanidine bicarbonate, an acrylic resin and water.   2. The aqueous coating composition according to claim 1, wherein the content of the aminoguanidine bicarbonate is 0.01% by weight or more in terms of solid content.   3. The aqueous coating composition according to claim 1, wherein the content of aminoguanidine bicarbonate is 30.0% by weight or less in terms of solid content.   Content of the said acrylic resin is 2-45 weight% in conversion of solid content, The water-based coating composition in any one of Claims 1-3 characterized by the above-mentioned.   A coating film characterized by being formed from the water-based coating composition according to any one of claims 1 to 4. A building material comprising: a base material; and the coating film according to claim 5 provided on at least a part of a surface of the base material.