Aqueous filler composition

Abstract

To provide an aqueous filler composition which, even when a wool roller is used, has less concealing unevenness, does not exert an adverse effect on finished appearance of the subsequent top coat, and forms a base coat film having crack resistance.SOLUTION: Provided is an aqueous filler composition for forming a base coating film using a wool roller before a top coat is applied onto a building outer wall, comprising an aqueous resin (A) having a glass transition temperature of 30°C or lower, a pigment (B), and a urethane aggregation type thickener (C), wherein the pigment volume concentration is within a range of 30 to 65%, the urethane aggregation type thickener (C) has, as a 5% aqueous solution, a viscosity of 3,000 mPa s or less, and a content of the urethane associated thickener (C) is 0.1 to 2.5 pts. mass as an active ingredient based on 100 pts. mass of the resin solid content contained in the filler composition.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a coating composition for surface preparation. [Background technology]

[0002] Conventionally, in the painting and finishing of the exterior walls of buildings, the base is prepared before the top coat is applied to provide weather resistance and beauty. Materials used for the base preparation include synthetic resin emulsion base preparation materials, which are generally called water-based fillers in the field of architectural paints.

[0003] Since the exterior walls of buildings expand and contract due to temperature changes, and cracks may occur over the long term, thermoplastic synthetic resin emulsions are used in base adjustment materials to give them elasticity that allows them to conform to the base.

[0004] In Patent Documents 1 and 2, the applicant has proposed an aqueous paint composition containing an aqueous copolymer dispersion and a pigment as an aqueous filler, characterized in that the aqueous copolymer dispersion contains an acrylate containing a linear or branched alkyl group and a carbonyl group-containing polymerizable unsaturated monomer as copolymerization components, the copolymerization ratio of the acrylate containing a linear or branched alkyl group being 50 mass% or more, and the volume concentration of the pigment in the composition being within the range of 15 to 60%.

[0005] Patent Document 3 discloses an undercoat paint containing an aqueous resin and a pigment, for forming an undercoat paint film that is in contact with the lower side of an aqueous topcoat paint film, characterized in that the pigment contains an extender pigment A having an average particle size of 1 to 30 μm, and an extender pigment B having an average particle size of 73 to 300 μm, and the volume concentration of the extender pigment A in the total volume of the aqueous resin and the pigment is 13% or more, the volume concentration of the extender pigment B is 17% or more, and the combined volume concentration of the extender pigment A and the extender pigment B is 30 to 80%. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2007-277451 A [Patent Document 2] JP 2008-031415 A [Patent Document 3] JP 2022-160152 A Summary of the Invention [Problem to be solved by the invention]

[0007] Paint rollers are widely used for painting buildings because they cause less paint to fly around than spray paint. Among them, wool rollers have a wool-like pile and are often used because they are inexpensive and allow for thin application.

[0008] On the other hand, mastic rollers are often used to apply water-based fillers. Mastic rollers are also called sand rollers, porous rollers, pattern rollers or sponge rollers, and have a roller pile with a mesh-like structure. This type of roller is characterized by its ability to pile up a lot of paint at once and to create uneven patterns such as ripples. However, mastic rollers are more expensive than wool rollers or brushes, and require a lot of paint per application, which causes problems such as storage issues at the painting site and weight loads on the object due to the large amount of paint applied to the object. In addition, if you want to make the most of the design of the existing exterior wall, it may be necessary to adjust the base coat thinly.

[0009] In response to such demands, when the aqueous fillers described in Patent Documents 1 to 3 are applied using a wool roller, problems arise in that the paint is not applied evenly to the wall surface, which can lead to uneven concealment, roughness on the coating surface, and poor finish of the top coat applied on top of it.

[0010] The present invention has been made in consideration of the above circumstances, and provides an aqueous filler composition which forms a crack-resistant base coating film with little unevenness in hiding even when a wool roller is used, without adversely affecting the finish of the topcoat paint applied thereon. [Means for solving the problem]

[0011] As a result of intensive research into solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by an aqueous filler composition comprising an aqueous resin (A) having a glass transition temperature of 30°C or less, a pigment (B), a urethane association type thickener (C), and water, the pigment volume concentration being within the range of 30 to 65%, the urethane association type thickener (C) having a viscosity of 3000 mPa s or less in a 5% aqueous solution, and contained in an amount of 0.1 to 2.5 parts by mass based on 100 parts by mass of resin solids contained in the aqueous filler composition, and have thus completed the present invention.

[0012] That is, the present invention provides: Item 1 An aqueous filler composition for forming a base coating film using a wool roller prior to painting a topcoat paint on an exterior wall of a building, comprising: An aqueous filler composition comprising an aqueous resin (A) having a glass transition temperature of 30°C or lower, a pigment (B) and a urethane association type thickener (C), the pigment volume concentration being within the range of 30 to 65%, the urethane association type thickener (C) having a viscosity of 3000 mPa s or less in a 5% aqueous solution, and a content of 0.1 to 2.5 parts by mass in terms of active ingredient, based on 100 parts by mass of resin solids contained in the aqueous filler composition. Section 2 An aqueous resin (A) having a glass transition temperature of 30°C or less, A copolymer (A1) of polymerizable unsaturated monomers that does not contain any of a carbonyl group-containing polymerizable unsaturated monomer and an alkoxysilyl group-containing polymerizable unsaturated monomer, and Item 2. The aqueous filler composition according to item 1, comprising a copolymer (A2) of polymerizable unsaturated monomers including a carbonyl group-containing polymerizable unsaturated monomer and an alkoxysilyl group-containing polymerizable unsaturated monomer. Section 3 An aqueous resin (A) having a glass transition temperature of 30°C or less, Item 1. The aqueous filler composition according to item 1, comprising: a copolymer (A1) of polymerizable unsaturated monomers that does not contain any of a carbonyl group-containing polymerizable unsaturated monomer and an alkoxysilyl group-containing polymerizable unsaturated monomer; and a copolymer (A3) of polymerizable unsaturated monomers that contains a carbonyl group-containing polymerizable unsaturated monomer but does not contain an alkoxysilyl group-containing polymerizable unsaturated monomer. Section 4 An aqueous resin (A) having a glass transition temperature of 30°C or less, Item 1. The aqueous filler composition according to item 1, comprising: a copolymer (A3-1) of polymerizable unsaturated monomers having a glass transition temperature of less than 0° C., which contains a carbonyl group-containing polymerizable unsaturated monomer and does not contain an alkoxysilyl group-containing polymerizable unsaturated monomer; and a copolymer (A3-2) of polymerizable unsaturated monomers having a glass transition temperature of 0° C. or higher, which contains a carbonyl group-containing polymerizable unsaturated monomer and does not contain an alkoxysilyl group-containing polymerizable unsaturated monomer. Section 5 5. The aqueous filler composition according to any one of items 1 to 4, wherein the pigment (B) contains titanium dioxide and calcium carbonate. Section 6 6. The aqueous filler composition according to any one of items 1 to 5, having a structural viscosity index (TI value) of 3.0 to 6.0. Section 7 A coating method comprising applying the aqueous filler composition according to any one of items 1 to 6 to an exterior wall of a building using a wool roller, drying the composition, and then applying a topcoat paint onto the resulting base coat. Section 8 The aqueous filler composition according to any one of items 1 to 6 is applied to the exterior wall of a building using a wool roller in an amount of 100 to 450 g / m 2 This coating method involves painting the surface so that the surface is within the range of 100 mm, drying the surface, and then painting the topcoat onto the resulting base coat using a wool roller. Regarding. Effect of the Invention

[0013] The aqueous filler composition of the present invention has good workability when applied with a wool roller, suppresses unevenness in coverage, and provides a base coat film with excellent crack resistance. In addition, the texture is good, so that the finish of the top coat applied thereon is also good. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The aqueous filler composition of the present invention is a coating material containing an aqueous resin (A), a pigment (B), a urethane associative thickener (C) and water. Each component will be described below.

[0015] Water-based resin (A): The aqueous resin (A) in the present invention can be any known water-soluble or water-dispersible resin without any particular limitation as long as it has a coating film-forming ability. When the aqueous resin (A) is water-dispersible, the resin portion can have a single-layer structure (homogeneous granular) or a multi-layer structure such as a core-shell structure, and in the case of a core-shell structure, the core and / or shell may be crosslinked. The aqueous resin (A) can be a copolymer of a polymerizable unsaturated monomer.

[0016] In this specification, a polymerizable unsaturated monomer is a monomer having a polymerizable unsaturated group, and examples of the polymerizable unsaturated group include a (meth)acryloyl group, a (meth)acrylamide group, a vinyl group, a vinyl ether group, an allyl group, a propenyl group, an isopropenyl group, and a maleimide group.

[0017] In this specification, "(meth)acrylate" means acrylate or methacrylate, "(meth)acrylic acid" means acrylic acid or methacrylic acid, "(meth)acryloyl" means acryloyl or methacryloyl, and "(meth)acrylamide" means acrylamide or methacrylamide.

[0018] Examples of the polymerizable unsaturated monomer include (i) linear or branched alkyl group-containing (meth)acryloyl monomers, such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, and stearyl (meth)acrylate; (ii) alicyclic alkyl group-containing (meth)acryloyl monomers such as cyclohexyl (meth)acrylate and isobornyl (meth)acrylate; (iii) aralkyl group-containing (meth)acryloyl monomers such as benzyl (meth)acrylate; (iv) alkoxyalkyl group-containing (meth)acryloyl monomers such as 2-methoxyethyl (meth)acrylate and 2-ethoxyethyl (meth)acrylate; (v) Fluorine-containing (meth)acryloyl monomers such as hexafluoroisopropyl (meth)acrylate, perfluorooctylmethyl (meth)acrylate, and perfluorooctylethyl (meth)acrylate; (vi) amino group-containing (meth)acryloyl monomers such as N,N-diethylaminoethyl (meth)acrylate; (vii) (meth)acrylamide; (viii) hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate, ε-caprolactone-modified products of the above hydroxyalkyl (meth)acrylates, and hydroxyl group-containing (meth)acryloyl monomers such as polyoxyethylene chain-containing (meth)acrylates whose molecular terminals are hydroxyl groups; (ix) (meth)acrylic acid, β-carboxyethyl acrylate, and other carboxyl group-containing (meth)acryloyl monomers; (x) epoxy group-containing (meth)acryloyl monomers such as glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 3,4-epoxycyclohexylethyl (meth)acrylate, and 3,4-epoxycyclohexylpropyl (meth)acrylate; (xi) isocyanato group-containing (meth)acryloyl monomers such as isocyanatoethyl (meth)acrylate; (xii) (meth)acryloyl monomers containing an oxidative curing group, such as dicyclopentenyloxyethyl (meth)acrylate, dicyclopentenyloxypropyl (meth)acrylate, and dicyclopentenyl (meth)acrylate; (xiii) compounds having at least two (meth)acryloyl groups in one molecule, such as allyl (meth)acrylate, ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tetra(meth)acrylate, glycerol di(meth)acrylate, 1,1,1-trishydroxymethylethane di(meth)acrylate, 1,1,1-trishydroxymethylethane tri(meth)acrylate, and 1,1,1-trishydroxymethylpropane tri(meth)acrylate; (xiv) Aromatic vinyl compounds such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, ethylstyrene, p-tert-butylstyrene, α-methylstyrene, α-methyl-p-methylstyrene, vinylethylbenzene, vinylxylene, vinylnaphthalene, and diphenylethylene; (xv) carbonyl group-containing polymerizable unsaturated monomers, such as acetoacetoxyethyl (meth)acrylate, diacetone (meth)acrylamide, (meth)acrolein, formylstyrol, vinyl alkyl ketones having 4 to 7 carbon atoms (e.g., vinyl methyl ketone, vinyl ethyl ketone, vinyl butyl ketone, etc.), and acetoacetoxy allyl esters; (xvi) alkoxysilyl group-containing polymerizable unsaturated monomers, such as γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltriethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane; (xvii) (meth)acrylonitrile; (xviii) vinyl ester compounds such as vinyl acetate and vinyl propionate; (xix) allyl alcohol; (xx) Maleic acid, crotonic acid; (xxi) epoxy group-containing allyl compounds such as allyl glycidyl ether; (xxii) Isocyanato group-containing polymerizable unsaturated monomers such as m-isopropenyl-α,α-dimethylbenzyl isocyanate; and the like.

[0019] In the present invention, the water-based resin (A) has a glass transition temperature of 30° C. or lower from the viewpoint of crack resistance of the base coating film. The glass transition temperature is preferably within the range of −25 to 20° C. In the present specification, the glass transition temperature (Tg) of the resin is calculated as follows.

[0020] 1 / Tg(K)=W1 / T1+W2 / T2+···W n / T n Tg(°C)=Tg(K)-273 In the formula, W1, W2,...W n are the mass fractions of each monomer, and T1, T2...T nis the glass transition temperature Tg (K) of the homopolymer of each polymerizable unsaturated monomer. The glass transition temperature of the homopolymer of each polymerizable unsaturated monomer is a value according to pages III-139 to 179 of Polymer Handbook (Second Edition, edited by J. Brandup·EH Immergut). When the glass transition temperature of the homopolymer is not clear, the static glass transition temperature is used when the homopolymer of the monomer is synthesized so as to have a weight average molecular weight of about 50,000.

[0021] The static glass transition temperature is determined, for example, by using a differential scanning calorimeter "DSC-50Q type" (manufactured by Shimadzu Corporation, product name) and using a sample from which volatile components have been removed by vacuum suction, measuring the heat change in the range of -100°C to +100°C at a heating rate of 3°C / min, and observing the first change point of the baseline on the low temperature side.

[0022] The method for polymerizing the above monomers is not particularly limited, and for example, the polymerization can be carried out by (co)polymerizing the above monomers in the presence of a polymerization initiator and an emulsifier according to a general emulsion polymerization method.

[0023] The aqueous resin (A) may be a single resin or a combination of multiple resins, so long as the resin has a glass transition temperature of 30° C. or lower.

[0024] Examples of the aqueous resin (A) that is of multiple types include, for example, (I) a copolymer (A1) of polymerizable unsaturated monomers that does not contain any of a carbonyl group-containing polymerizable unsaturated monomer and an alkoxysilyl group-containing polymerizable unsaturated monomer, and An embodiment including a copolymer (A2) of polymerizable unsaturated monomers including a carbonyl group-containing polymerizable unsaturated monomer and an alkoxysilyl group-containing polymerizable unsaturated monomer; (II) An embodiment including a copolymer (A1) of polymerizable unsaturated monomers containing neither a carbonyl group-containing polymerizable unsaturated monomer nor an alkoxysilyl group-containing polymerizable unsaturated monomer, and a copolymer (A3) of polymerizable unsaturated monomers containing a carbonyl group-containing polymerizable unsaturated monomer but not containing an alkoxysilyl group-containing polymerizable unsaturated monomer, or (III) An embodiment including a copolymer (A3-1) of polymerizable unsaturated monomers having a glass transition temperature of less than 0° C. and including a carbonyl group-containing polymerizable unsaturated monomer and not including an alkoxysilyl group-containing polymerizable unsaturated monomer, and a copolymer (A3-2) of polymerizable unsaturated monomers having a glass transition temperature of 0° C. or higher and including a carbonyl group-containing polymerizable unsaturated monomer and not including an alkoxysilyl group-containing polymerizable unsaturated monomer. etc.

[0025] The copolymer (A1) of polymerizable unsaturated monomers containing neither a carbonyl group-containing polymerizable unsaturated monomer nor an alkoxysilyl group-containing polymerizable unsaturated monomer is at least one kind of polymerizable unsaturated monomer selected from the group consisting of the above polymerizable unsaturated monomers (i) to (xxii), which does not contain a carbonyl group-containing polymerizable unsaturated monomer nor an alkoxysilyl group-containing polymerizable unsaturated monomer as a monomer.

[0026] In a preferred embodiment, the copolymer (A1) of polymerizable unsaturated monomers containing neither a carbonyl group-containing polymerizable unsaturated monomer nor an alkoxysilyl group-containing polymerizable unsaturated monomer is preferably a polymer of monomers containing monomers (i), (viii) and (ix) and optionally containing at least one monomer selected from monomers (ii), (xiii) and (xi).

[0027] The aqueous resin (A) is preferably contained in an amount of 5 to 95 parts by mass, and more preferably 15 to 80 parts by mass in terms of the solid content, based on 100 parts by mass of the solid content of the aqueous filler composition.

[0028] In this specification, the term "solid content" refers to the residue after removing volatile components such as water and organic solvents, and means non-volatile components such as resins, hardeners, pigments, etc. For example, the term "solid content" refers to the residue after weighing out 1 gram of a sample into a heat-resistant container such as an aluminum foil cup, spreading the sample on the bottom of the container, and drying at 110°C for 1 hour.

[0029] Pigment (B): The aqueous filler composition of the present invention contains a pigment (B). Examples of the pigment (B) include color pigments such as titanium white, zinc oxide, alumina, carbon black, graphite, black iron oxide, iron-manganese composite oxide, iron-copper-manganese composite oxide, iron-chromium-cobalt composite oxide, copper-chromium composite oxide, copper-manganese-chromium composite oxide, ferric oxide (red oxide), molybdate orange, permanent red, permanent carmine, anthraquinone red, perylene red, quinacridone red, yellow iron oxide, titanium yellow, fast yellow, benzimidazolone yellow, chrome green, cobalt green, phthalocyanine green, ultramarine blue, Prussian blue, cobalt blue, phthalocyanine blue, quinacridone violet, dioxazine violet, aluminum pigments, and pearl pigments; and extender pigments such as calcium carbonate, talc, barium sulfate, mica, clay, silica, and aluminum hydroxide.

[0030] The pigment volume concentration of the aqueous filler composition of the present invention is 30 to 65%, and preferably in the range of 35 to 55%. In this specification, the "pigment volume concentration" refers to the volume ratio of the pigment to the total solid content of the total resin content and total pigment content in the paint. By having a pigment volume concentration of 30 to 65%, the paint workability with a wool roller is good, the texture does not affect the finish of the topcoat paint, and a base coat film with excellent crack resistance is obtained.

[0031] The specific gravity of the pigment, which is the basis for calculating the volume of the pigment, should be the value taken from the catalogue. If this is not clear, the value should be taken from the Paint Raw Materials Handbook, 9th Edition (Japan Paint Manufacturers Association). The specific gravity of the resin solids should be approximately 1.

[0032] In this specification, when the pigment volume concentration is calculated and when the "resin" is used as the basis for the content of the urethane associative thickener described below, it refers to, for example, the aqueous resin (A), aqueous resins other than the aqueous resin (A) that are blended as necessary, and coating film-forming components such as crosslinking agents, but does not include various additives such as urethane associative thickeners, dispersants, or defoamers.

[0033] The pigment (B) preferably contains titanium white and calcium carbonate. The total mass of titanium white and calcium carbonate based on 100 parts by mass of the resin solid content contained in the aqueous filler composition is preferably in the range of 100 to 500 parts by mass, more preferably 150 to 400 parts by mass. The mass of titanium white based on 100 parts by mass of the total mass of titanium white and calcium carbonate is preferably 5 parts by mass or more and less than 50 parts by mass, particularly preferably 10 to 20 parts by mass.

[0034] Urethane associative thickener (C): The aqueous filler composition of the present invention contains a urethane association type thickener (C). The urethane association type thickener is a urethane resin having a hydrophobic site (hydrophobic group) and a hydrophilic site (hydrophilic group), and examples of the hydrophobic group include a hydrocarbon group, and examples of the hydrophilic group include an ether bond.

[0035] The urethane association type thickener (C) is commercially available. Examples of commercially available products include the ADEKA Nol series (manufactured by ADEKA, trade name) and the SN Thickener series (manufactured by SAN NOPCO LTD.).

[0036] In the present invention, as the urethane association type thickener (C), a urethane association type thickener having a viscosity of 3000 mPa s or less in a 5% aqueous solution is used. Specifically, a urethane association type thickener having a viscosity of 3000 mPa sec or less, preferably 100 to 1000 mPa sec, when diluted with deionized water to give an active ingredient concentration of 5% by mass, is used.

[0037] The active ingredient concentration is determined based on the active ingredient concentration listed in the catalog value of the urethane associative thickener. If the active ingredient concentration of the urethane associative thickener is unclear, the solids concentration of the urethane associative thickener is measured and used as the active ingredient concentration of the urethane associative thickener. The solids concentration is calculated by weighing out 1 gram of sample into a heat-resistant container such as an aluminum foil cup, spreading the sample on the bottom of the container, drying at 110°C for 1 hour, weighing the mass of the residue after drying, and determining the ratio of the mass of the components remaining after drying to the total mass of the sample before drying.

[0038] The viscosity of a 5% aqueous solution is measured by using a B-type viscometer with a sample at 25°C and a rotation speed of 60 rpm for one minute.

[0039] In the present invention, the urethane association type thickener (C) can be used alone or in combination, and the total content is within the range of 0.1 to 2.5 parts by mass, preferably 0.2 to 1.5 parts by mass, in terms of the amount of active ingredient, based on 100 parts by mass of the resin solid content contained in the aqueous filler composition. The amount of active ingredient refers to the amount of the urethane association type thickener (C), and in the case where the urethane association type thickener (C) is a commercially available product, it refers to the amount of the urethane association type thickener (C) excluding other parts such as the diluent.

[0040] By containing a specific amount of the urethane associative thickener (C) having such properties, the aqueous filler composition of the present invention has the effect of providing excellent workability in painting with a wool roller, suppressing unevenness in concealment even on exterior walls having an uneven pattern formed on the surface, and providing an undercoat film with a texture that does not affect the finish of the topcoat paint. When a urethane associative thickener with a dilution viscosity of more than 3000 mPa·sec is used, the workability in painting with a wool roller is poor and unevenness in concealment occurs, which is not preferable.

[0041] The reason why the above effect is obtained depending on the type of urethane association type thickener (C) is not clear, but it is believed that a urethane association type thickener having a viscosity of 3000 mPa·sec or less when diluted with deionized water has moderate hydrophobic properties, and it is believed that the presence of a specific amount of a urethane association type thickener that satisfies this condition in the aqueous filler composition, which is the coating liquid, allows the coating liquid to be controlled to a moderate viscosity. As a result, the wool roller is easily moved during coating, and coating workability is improved. In addition, when the surface of the coating object is not flat but has unevenness such as a pattern pattern, the film thickness of the convex parts tends to become thin when the coating is applied, but since the present invention contains a specific amount of a specific urethane association type thickener (C), it is assumed that the coating liquid is likely to remain on the convex parts, and a base coating film with less unevenness in hiding can be obtained.

[0042] water: The aqueous filler composition of the present invention contains water as a diluting medium. The water content may differ between the storage state and the coating state. The water content in the storage state is 5 to 40 parts by mass, preferably 10 to 35 parts by mass, based on 100 parts by mass of the aqueous filler composition. In the coating state, the coating contractor mixes water appropriately, taking into consideration the state of the coating surface, the temperature during coating, and the like. The amount of water mixed is preferably about 0 to 20 parts by mass, based on 100 parts by mass of the aqueous filler composition.

[0043] Other Ingredients: In addition to the above-mentioned components, the aqueous filler composition of the present invention may contain other components such as an aqueous resin other than the aqueous resin (A) having a glass transition temperature of 30° C. or less, a crosslinking agent, a thickener other than the urethane association type thickener (C), a dispersant, a film-forming assistant, a plasticizer, an antifreeze agent, an organic solvent, an antifoaming agent, an antiseptic, an antifungal agent, a catalyst, etc. Each of these other components may be used alone or in combination of two or more.

[0044] When the other aqueous resin is contained, the content of the other aqueous resin is less than 50 parts by solid mass, particularly less than 10 parts by mass, per 100 parts by total solid mass of the resins contained in the aqueous filler composition.

[0045] The crosslinking agent can be selected depending on the crosslinking functional group contained in the aqueous resin component, and specific examples thereof include hydrazide compounds, polyamine compounds, polyisocyanate compounds, and polycarboxylic acid compounds.

[0046] Examples of the other thickeners include polyacrylic acid-based thickeners, cellulose-based thickeners, and urethane association type thickeners that do not satisfy the requirements for the urethane association type thickener (C) of the present invention.

[0047] The aqueous filler composition of the present invention has a structural viscosity index (TI value) of 3.0 to 6.0, preferably 4.3 to 5.5. By setting the viscosity characteristics of the aqueous filler composition under such conditions, it is possible to obtain a base coating film with good texture, which is easy to apply with a wool roller and suppresses uneven covering even on uneven surfaces. The structural viscosity index (TI) value is defined by the following equation (1). TI value = Va / Vb (1) In formula (1), Va is the viscosity (mPa sec) of the aqueous filler composition measured at 25° C. with a B-type viscometer at a rotation speed of 6 rpm for 1 minute, and Vb is the viscosity (mPa sec) of the aqueous filler composition measured at the same rotation speed of 60 rpm for 1 minute. The viscosity of the aqueous filler composition is measured at the time when it is prepared for use in coating.

[0048] Painting Method: The aqueous filler composition of the present invention is applied using a wool roller. If necessary, it can be diluted with water before application. A wool roller is made by implanting fiber hairs in a cylindrical member, and those using wool-like fiber hairs are known. There are various types of wool rollers with different hair lengths, materials, sizes, and shapes, and they can be broadly classified into three types, which are classified by the length from the surface of the cylindrical member to the tip of the hair (hereinafter referred to as the hair length). Specifically, there are short-hair rollers with a short hair length of about 4 to 5 mm, medium-hair rollers with a medium hair length of about 13 mm, and long-hair rollers with a hair length of 20 mm or more.

[0049] The aqueous filler composition of the present invention provides a base coat film with little unevenness in covering even when applied in a thin, small amount, and has little effect on the appearance of the subsequent top coat. Specific examples of the amount of application are, for example, 100 to 450 g / m 2 , especially 120~400g / m 2 The coating may be dried at room temperature or by heating, but room temperature drying is preferred.

[0050] The coating amount is calculated from the consumed mass of the aqueous sealer composition used in the coating step and the coating area.

[0051] The object on which the base coating film is formed using the aqueous filler composition of the present invention is the exterior wall of a building. Examples of the building include houses, office buildings, public facilities, and commercial facilities. Examples of the substrate constituting the exterior wall include inorganic material substrates, wood substrates, metal substrates, and plastic substrates. The exterior wall of the building may have an old coating film. The shape of the old coating film is not limited, and may be flat or may have various three-dimensional patterns. Examples of the pattern pattern include lysine, orange peel pattern, ripple pattern, crater pattern, stucco pattern, trowel wave finish, brush finish, etc. In addition, before applying the aqueous filler composition, a sealer coating may be applied depending on the type and condition of the exterior wall of the building.

[0052] In the present invention, the aqueous filler composition is used to form a base coat, and then a top coat paint is applied thereon. As the top coat paint, any top coat paint known in the field of architectural paints can be used without limitation. Specifically, the top coat paint may include paints containing water-based or solvent-based resins such as acrylic resins, acrylic silicone resins, polyolefin resins, silicone resins, polyurethane resins, fluororesins, and biodegradable resins as resin binders, and it is preferable to use an aqueous paint containing a water-based resin.

[0053] The method of applying the topcoat paint is not particularly limited, and conventionally known methods such as roller, air spray, airless spray, lysine gun, universal gun, brush, and brush painting can be used. Drying at room temperature is preferable, but heat drying is also possible as necessary. The amount of topcoat paint applied is not particularly limited, and is, for example, 100 to 450 g / m 2 , preferably 120 to 400 g / m 2 is within the range.

[0054] The undercoat film formed by the aqueous filler composition of the present invention has excellent hiding properties, so that even if a topcoat paint is applied thinly with a wool roller, it can provide a beautiful appearance to the exterior wall of a building and provide sufficient protection. EXAMPLES

[0055] The present invention will be described in more detail below with reference to Production Examples, Examples, and Comparative Examples, but the present invention is not limited thereto. In each example, "parts" means parts by mass, and "%" means % by mass.

[0056] Manufacture of water-based resin Manufacturing Example 1 35 parts of deionized water and 1 part of Newcol 707SF (Note 1) were charged into a reaction vessel equipped with a thermometer, thermostat, stirrer, and dropping device, and the mixture was stirred and mixed in a nitrogen stream and heated to 85°C. Next, 3% of a pre-emulsion made by emulsifying the components shown below and 8 parts of a 2.5% aqueous solution of ammonium persulfate were added to the reaction vessel and kept at 85°C for 20 minutes. 40 parts deionized water Styrene 25 parts 2-Ethylhexyl acrylate 70 parts 2-Hydroxyethyl acrylate 1 part Methacrylic acid 4 parts Newcol 707SF (Note 1) 8 copies Then, the remaining pre-emulsion and 8 parts of 2.5% ammonium persulfate aqueous solution were dropped into the reaction vessel over 4 hours, and aging was carried out for 2 hours after the end of the dropwise addition. Then, the mixture was cooled to 30°C, and the solid content was adjusted to 50% and the pH to 8.0 using ammonia water and deionized water. Next, the mixture was filtered through a 200-mesh nylon cloth and discharged to obtain a water-dispersed aqueous resin (A1) with a glass transition temperature of -22°C. (Note 1) Newcol 707SF: Product name, manufactured by Nippon Nyukazai Co., Ltd., anionic surfactant with a polyoxyethylene chain, non-volatile content 30%.

[0057] Manufacturing Examples 2 to 5 Aqueous resins (A2), (A3-1) and (A3-2), as well as aqueous resin (X), were obtained by synthesizing in the same manner as in Production Example 1, except that the monomer composition in Production Example 1 was changed to the formulation shown in Table 1 below.

[0058] [Table 1]

[0059] Preparation of the aqueous filler composition Examples 1 to 13 and Comparative Examples 1 to 6 The components shown in Table 2 were charged into a stainless steel container with stirring, and the mixture was stirred for 15 minutes until homogenized using a homodisper manufactured by PRIMIX, to produce aqueous filler compositions (X-1) to (X-19). Note that in Table 2, the blending amounts of materials containing volatile components are indicated by mass including the volatile components.

[0060] [Table 2]

[0061] (Note 2) DISPER BYK-190: Product name, manufactured by BYK Co., Ltd., water-based wetting and dispersing agent, aqueous solution of polyether-modified styrene-maleic anhydride copolymer, solid content 40% (Note 3) SN Deformer 395: Product name, manufactured by San Nopco Ltd., defoamer (Note 4) SN Thickener 615: Product name, manufactured by San Nopco Ltd., acrylic polymer, active ingredient 30% (Note 5) SN Thickener 625N: Product name, manufactured by San Nopco Ltd., urethane association type thickener, active ingredient 15% (Note 6) ADEKA NOL UH-420: Product name, manufactured by ADEKA Corporation, urethane association type thickener, active ingredient 30% (Note 7) Primal RM12W: Trade name, manufactured by Dow Chemical Co., urethane associative thickener, active ingredient 19% (Note 8) ADEKA NOL UH-530: ADEKA Corporation, urethane association type thickener, active ingredient 30% (Note 9) SN Thickener 612NC: Product name, manufactured by San Nopco Ltd., urethane association type thickener, active ingredient 45%, (Note 10) SN Thickener 665T: Product name, manufactured by San Nopco Ltd., urethane association type thickener, active ingredient 10% (Note 11) Viscosity of urethane associative thickener: Each urethane associative thickener was diluted with deionized water so that the active ingredient concentration was 5% by mass, and the sample was cooled to 25°C and measured using a Brookfield viscometer at a rotation speed of 60 rpm for 1 minute.

[0062] <Evaluation test> The aqueous filler compositions obtained in the Examples and Comparative Examples were subjected to the following evaluations. The results are shown in Table 2. 1. Ease of painting with wool rollers On a slate board measuring approximately 1 square metre, "Ares Holder GII" (product name, Kansai Paint Co., Ltd., water-based, slightly elastic base adjustment material) was applied with a porous roller in a ripple pattern at a rate of 0.8 kg / m. 2On top of that, "Ares Aqua Gloss" (product name, Kansai Paint Co., Ltd., acrylic water-based topcoat paint) was mixed to a blue-gray color and painted with a wool roller, and the painted plate obtained after drying at 23°C for 14 days was regarded as the old paint film and used as the substrate. Onto this rippled painted surface, each of the aqueous filler compositions obtained in the Examples and Comparative Examples was applied with a wool roller ("Melon" wool roller manufactured by PIA Co., Ltd., bristle length 25 mm) in an amount of 220 g / m 2 The coating workability (ease of movement of wool roller, paint rebound) was evaluated. After that, it was dried at 23°C for 7 days to obtain a coated panel for evaluation. (1) Ease of moving the wool roller The aqueous filler compositions of the Examples and Comparative Examples were applied with a wool roller, and the ease of movement was evaluated according to the following criteria. ◎: The rollers are light and very easy to move. 〇: The rollers can feel a little heavy in some places, but are easy to move. △: The roller feels a little heavy and a little difficult to move. ×: The roller feels very heavy and is very difficult to move. (2) Paint splash resistance The degree of splash back of the paint when each of the aqueous filler compositions of the Examples and Comparative Examples was applied with a wool roller was evaluated according to the following criteria. ◎: Almost no bounce 〇: There is some bounce, but it is still practical △: There is obvious bounce ×: Rebound is noticeable.

[0063] 2. Evaluation of painted boards The coated panels prepared in the above evaluation of painting workability were evaluated according to the following evaluation items. (1) Hiding ability of the aqueous filler composition on the pattern coating film The painted panels prepared in the above evaluation of painting workability were visually observed from a distance of 50 cm, and the state in which the blue-gray base color was visible was rated on the following four levels. ◎: The undercoat color is not noticeable ○: The base color shows through slightly in the convex parts, but is not noticeable when viewed from a distance of 1m. △: The base color is visible throughout the entire surface, and is somewhat noticeable when viewed from a distance of 1m. ×: The undercoat color is noticeably visible overall, and is quite noticeable when viewed from a distance of 1m. (2) Texture of the aqueous filler composition on the pattern coating The coated panels prepared in the above evaluation of painting workability were visually observed from a distance of 50 cm, and the overall texture of the water-based filler coating surface was rated into the following four levels. ◎: There are almost no roller marks (thread-like marks left by the roller passing over the surface), and the entire coating surface has a smooth, uniform texture. ○: Roller marks (thread-like marks left by the roller) are slightly visible, but when viewed from a distance of 1m, the entire painted surface has a uniform texture. △: Roller marks (thread-like marks left by the roller passing over) are visible all over the painted surface, and the texture is rather poor even when viewed from a distance of 1m. ×: Roller marks (thread-like marks left by the roller passing over) are clearly visible over the entire painted surface, and the texture is poor even when viewed from a distance of 1m. (3) Crack resistance The painted panels prepared in the above painting workability evaluation were cut to a size of 20cm wide x 30cm long, and the back and sides were seal-painted with "Cera M Retan Clear" (a weak solvent-based two-component urethane clear paint manufactured by Kansai Paint Co., Ltd.). After drying for 48 hours, a hot and cold cycle test was carried out for a total of 10 cycles, with one cycle being immersed in water (23°C) for 18 hours, exposed to air at -20°C for 3 hours, and exposed to air at 50°C for 3 hours. After this, the surface of the coating was visually inspected for cracks. ◎: No cracks occurred. 〇: Cracks occurred in less than 5% of the area. △: Cracks are observed over 5% or more but less than 50% of the surface area. ×: Cracks are observed over 50% or more of the area.

[0064] 3. Evaluation of adhesion with topcoat A flexible board (70mm x 150mm x 4mm) was coated with 100g / m of "Eco Cation Sealer" (a water-based cationic emulsion sealer manufactured by Kansai Paint Co., Ltd.). 2 The paint was applied using a brush so that the paint had a thickness of 220 g / m2, and then dried at 23°C for 18 hours. 2 The paint was applied using a wool roller ("Melon" wool roller manufactured by PIA, bristle length 25 mm) so that the paint was applied as shown below. The paint was then dried at a temperature of 23°C for 7 days, and "Cosmo Silicon" (water-based acrylic silicone topcoat paint manufactured by Kansai Paint Co., Ltd.) was applied on top at a rate of 120 g / m 2 The test panels were then immersed in water at 23°C for 7 days, after which they were removed and dried at 23°C for 1 day. A knife was then used to make cross-cut scratches that reached the base material of the test panels, and adhesion was evaluated using adhesive tape. ◎: No peeling at all between the aqueous filler composition and the top coat ○: The peeling area ratio between the aqueous filler composition and the top coat is less than 5% of the area of ​​the test plate. △: The peeling area ratio between the aqueous filler composition and the top coat is 5% or more and less than 30% of the area of ​​the test coated plate. ×: Almost the entire surface of the aqueous filler composition and the top coat peeled off in a sheet-like manner.

Claims

1. An aqueous filler composition for forming a base coating film using a wool roller prior to painting a topcoat paint on an exterior wall of a building, comprising: An aqueous filler composition comprising an aqueous resin (A) having a glass transition temperature of 30° C. or lower, a pigment (B), a urethane association type thickener (C), and water, the pigment volume concentration being within the range of 30 to 65%, the urethane association type thickener (C) having a viscosity of 3000 mPa·s or lower in a 5% aqueous solution, and a content of 0.1 to 2.5 parts by mass in terms of the amount of active ingredient based on 100 parts by mass of resin solids contained in the aqueous filler composition.

2. An aqueous resin (A) having a glass transition temperature of 30° C. or less, A copolymer (A1) of polymerizable unsaturated monomers that does not contain any of a carbonyl group-containing polymerizable unsaturated monomer and an alkoxysilyl group-containing polymerizable unsaturated monomer, and The aqueous filler composition according to claim 1, comprising a copolymer (A2) of polymerizable unsaturated monomers including a carbonyl group-containing polymerizable unsaturated monomer and an alkoxysilyl group-containing polymerizable unsaturated monomer.

3. An aqueous resin (A) having a glass transition temperature of 30° C. or less, The aqueous filler composition according to claim 1, comprising: a copolymer (A1) of polymerizable unsaturated monomers that does not contain either a carbonyl group-containing polymerizable unsaturated monomer or an alkoxysilyl group-containing polymerizable unsaturated monomer; and a copolymer (A3) of polymerizable unsaturated monomers that contains a carbonyl group-containing polymerizable unsaturated monomer but does not contain an alkoxysilyl group-containing polymerizable unsaturated monomer.

4. An aqueous resin (A) having a glass transition temperature of 30° C. or less, The aqueous filler composition according to claim 1, comprising: a copolymer (A3-1) of polymerizable unsaturated monomers having a glass transition temperature of less than 0°C, containing a carbonyl group-containing polymerizable unsaturated monomer, and not containing an alkoxysilyl group-containing polymerizable unsaturated monomer; and a copolymer (A3-2) of polymerizable unsaturated monomers having a glass transition temperature of 0°C or higher, containing a carbonyl group-containing polymerizable unsaturated monomer, and not containing an alkoxysilyl group-containing polymerizable unsaturated monomer.

5. The aqueous filler composition according to claim 1 , wherein the pigment (B) comprises titanium dioxide and calcium carbonate.

6. The aqueous filler composition according to claim 1, having a structural viscosity index (TI value) of 3.0 to 6.

0.

7. A coating method comprising applying the aqueous filler composition according to any one of claims 1 to 6 to an exterior wall of a building using a wool roller, drying the composition, and then applying a topcoat paint onto the resulting base coating film.

8. The aqueous filler composition according to any one of claims 1 to 6 is applied to the exterior wall of a building using a wool roller in an amount of 100 to 450 g / m ２ This is a coating method in which the paint is applied within the range, dried, and then a topcoat is applied to the formed base coat using a wool roller.

Images