Film formation method

Abstract

To provide a method for easily forming a coated surface having natural texture and having high beauty appearance.SOLUTION: A film formation method includes a step (1) of coating an aqueous coating material to a coated surface, and forming a coating surface, a step (2) of supplying water and / or a hydrophilic solvent to the coating surface, and uniformizing the coating surface using a pressing tool, and a step (3) of drying the coating surface, in which the aqueous coating material contains 3-30 pts.wt. of an aqueous resin and 0.1-50 pts.wt. of a hydrophobic solvent with respect to 100 pts.wt. of an aggregate.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for forming a coated surface applicable to the surface decoration of the inner and outer walls of buildings, civil engineering structures, and the like.

Background Art

[0002] Conventionally, coatings having various design properties have been formed on the walls of buildings, civil engineering structures, and the like. Patent Document 1 discloses a method in which a colored emulsion paint is sequentially applied, and then, while the coating is in a fluid state, the coating is pressed to form a patterned coating.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, a colored emulsion paint mainly composed of a resin emulsion and a coloring pigment is used. Therefore, the color of the formed coating is based on the color development of paint, and there is room for improvement in terms of texture. Further, in the method of Patent Document 1, when pressing the coating, stringing or the like may occur in the coating, and there is a risk of impairing the aesthetic appearance.

[0005] The present invention has been made in view of such problems, and an object thereof is to provide a method capable of easily forming a highly aesthetic coated surface having a natural texture.

Means for Solving the Problems

[0006] As a result of intensive studies to solve the above problems, the present inventor has conceived a film-forming method that includes a step of applying a specific aqueous topcoat material to a surface to be coated to form a coated surface, a step of supplying water and / or a hydrophilic solvent to the coated surface and leveling the coated surface using a pressing tool, and has completed the present invention.

[0007] That is, the present invention has the following features. 1. A film-forming method using an aqueous topcoat material, For a surface to be coated, (1) A step of applying an aqueous topcoat material to form a coated surface, (2) A step of supplying water and / or a hydrophilic solvent to the coated surface and leveling the coated surface using a pressing tool, (3) A step of drying the coated surface, is performed, The aqueous topcoat material contains 3 to 30 parts by weight of an aqueous resin and 0.1 to 50 parts by weight of a hydrophobic solvent with respect to 100 parts by weight of an aggregate, and is characterized by the film-forming method. 2. The film-forming method according to 1., wherein the hydrophobic solvent has a solubility in water at 20°C of 10 g / 100 gH2O or less. 3. The film-forming method according to 1. or 2., wherein in the step (1), a coated surface is formed using a brush. 4. The film-forming method according to any one of 1. to 3., wherein in the step (2), the coated surface is leveled using a brush.

Effect of the Invention

[0008] According to the present invention, a highly aesthetic coated surface with a natural texture can be easily formed.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments for carrying out the present invention will be described in detail.

[0010] In the present invention, a coated surface is formed on a surface to be coated using a specific aqueous topcoat material.

[0011] [Coated surface] Examples of the coated surface include those constituting the inner and outer walls of buildings, civil engineering structures, and the like. Examples of the base material constituting the coated surface include concrete, mortar, ceramic tiles, fiber-reinforced cement boards, calcium silicate cement boards, slag cement perlite boards, cement boards, ALC boards, siding boards, gypsum boards, plywood, extruded boards, steel plates, plastic boards, and the like. The surfaces of these base materials may be those subjected to some surface treatment (for example, treatment with putty, sealer, surfacer, filler, etc.), those on which a coating film has already been formed, those to which wallpaper or the like is adhered, or the like.

[0012] [Water-based topcoat] The water-based topcoat in the present invention contains an aggregate, a water-based resin, and a hydrophobic solvent. In the present invention, by using such a water-based topcoat, a highly aesthetic coating surface with a natural texture can be easily formed.

[0013] The water-based topcoat in the present invention contains an aggregate as a main component. Such an aggregate is a component that contributes to imparting a natural texture, suppressing monochromatism, and the like. Examples of the aggregate include crushed materials such as marble, granite, serpentine, granite, fluorite, gypsum, feldspar, silica stone, silica sand, crushed ceramic materials, crushed ceramic materials, crushed glass materials, glass beads, crushed resin materials, resin beads, metal grains, or those obtained by applying a colored coating to the surfaces of these. These can be used alone or in combination of two or more.

[0014] The water-based topcoat can contain a colored aggregate as an aggregate. As the colored aggregate, an aggregate in which some color can be visually recognized can be used. The color of the colored aggregate may be, for example, of natural origin or artificially imparted. In the present invention, by using such a colored aggregate, color development is imparted, and the texture, naturalness, fineness, etc. can also be enhanced.

[0015] The average particle size of the aggregate is preferably 0.05 to 3 mm, more preferably 0.06 to 1 mm, still more preferably 0.07 to 0.5 mm, and particularly preferably 0.075 to 0.2 mm. When the aggregate has such an average particle size, a coating surface with high aesthetic properties can be formed with a relatively small coating amount, and the film thickness and weight of the coating can be reduced. The average particle size of the aggregate is a value obtained by sieving using a metal mesh sieve specified in JIS Z8801-1:2000 and calculating the average value of its weight distribution. In the present invention, "α to β" is synonymous with "α or more and β or less".

[0016] The aqueous resin in the aqueous topcoat is a component that plays a role in immobilizing aggregates and the like. As the aqueous resin, a water-soluble resin and / or a water-dispersible resin (resin emulsion) can be used, and an embodiment containing a water-dispersible resin is particularly preferable. By using a water-soluble resin and / or a water-dispersible resin, an aqueous topcoat can be obtained. Examples of the type of resin include cellulose, polyvinyl alcohol, ethylene resin, vinyl acetate resin, polyester resin, alkyd resin, vinyl chloride resin, epoxy resin, acrylic resin, urethane resin, acrylic silicone resin, fluororesin, etc., or a composite system thereof. These can be used alone or in combination of two or more. Also, these aqueous resins may or may not have crosslinking reactivity. The glass transition temperature of the aqueous resin is preferably -30 to 70 °C, more preferably -20 to 50 °C. The glass transition temperature can be determined by Fox's formula.

[0017] When a binder having crosslinking reactivity is used as the aqueous resin, the durability, weather resistance, etc. of the coating can be enhanced, the occurrence of defects such as cracks, peeling, and swelling can be prevented, and the initial aesthetic properties can be maintained over a long period. Examples of such aqueous resins include those that undergo a crosslinking reaction between a reactive functional group-containing aqueous resin and its crosslinking agent, or those that undergo a crosslinking reaction between reactive functional group-containing aqueous resins.

[0018] Examples of such combinations of reactive functional groups include, for example, a carboxyl group and a carbodiimide group, a carboxyl group and an epoxy group, a carboxyl group and an aziridine group, a carboxyl group and an oxazoline group, a hydroxyl group and an isocyanate group, a carbonyl group and a hydrazide group, an epoxy group and a hydrazide group, an epoxy group and an amino group, an aldehyde group and a semicarbazide group, a ketone group and a semicarbazide group, combinations of alkoxysilyl groups, a carboxyl group and a metal compound, etc. These can be used alone or in combination of two or more.

[0019] The mixing ratio of the aqueous resin is 3 to 30 parts by weight, preferably 4 to 25 parts by weight, more preferably 5 to 20 parts by weight, and even more preferably 6 to 19 parts by weight in terms of solid content based on 100 parts by weight of the aggregate. When the mixing ratio of the aqueous resin is at least the above lower limit, it is suitable in terms of improving coating workability, suppressing film cracking, etc. When the mixing ratio of the aqueous resin is at most the above upper limit, it is suitable in terms of improving coating workability, imparting a natural texture, etc.

[0020] The hydrophobic solvent in the aqueous topcoat contributes to improving coating workability, suppressing film cracking, and ultimately improving the aesthetic appearance of the film.

[0021] The hydrophobic solvent preferably contains a hydrophobic solvent having a solubility in water at 20°C of 10 g / 100 g H2O or less (more preferably 8 g / 100 g H2O or less, even more preferably 6 g / 100 g H2O or less, and particularly preferably 5 g / 100 g H2O or less). The solubility in water at 20°C refers to the maximum mass (g) of the target solvent that can be dissolved in 100 g of water.

[0022] Specific examples of the hydrophobic solvent include, for example, ethylene glycol monohexyl ether, ethylene glycol 2-ethylhexyl ether, ethylene glycol monobutyl ether acetate, ethylene glycol dibutyl ether, diethylene glycol monohexyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol dibutyl ether, propylene glycol monobutyl ether, propylene glycol phenyl ether, propylene glycol diacetate, dipropylene glycol monobutyl ether, dipropylene glycol tertiary butyl ether, tripropylene glycol monobutyl ether, octylene glycol, 2-ethylhexylene glycol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, benzyl alcohol and the like. These can be used alone or in combination of two or more. In the present invention, it is particularly preferable to contain 2,2,4-trimethyl-1,3-pentanediol diisobutyrate as the hydrophobic solvent.

[0023] The mixing ratio of the hydrophobic solvent is 0.1 to 50 parts by weight, preferably 0.5 to 40 parts by weight, more preferably 0.8 to 30 parts by weight, and still more preferably 1 to 20 parts by weight with respect to 100 parts by weight of the aggregate. When the mixing ratio of the hydrophobic solvent is not less than the above lower limit, it is suitable in terms of improving coating workability, suppressing film cracking, etc. When the mixing ratio of the hydrophobic solvent is not more than the above upper limit, it is suitable in terms of ensuring the stability of the aqueous topcoat material, etc., and the effects of improving coating workability, suppressing film cracking, etc. can be sufficiently obtained.

[0024] The water-based topcoat material can contain an extender pigment. The extender pigment is a component that contributes to imparting a natural texture and improving the painting workability. Examples of the extender pigment include heavy calcium carbonate, light calcium carbonate, kaolin, clay, pottery clay, china clay, diatomaceous earth, hydrated fine silica powder, talc, barite powder, barium sulfate, precipitated barium sulfate, barium carbonate, magnesium carbonate, silica powder, aluminum hydroxide, etc., and one or more of these can be used. It is desirable that the average particle size of the extender pigment is smaller than the average particle size of the aggregate. The average particle size of the extender pigment is preferably less than 50 μm, more preferably 0.5 to 45 μm, and even more preferably 1 to 40 μm. The average particle size of the extender pigment is a value measured by a laser diffraction particle size distribution measuring device.

[0025] The mixing ratio of the extender pigment can be 20 to 500 parts by weight with respect to 100 parts by weight of the aggregate, preferably 70 to 350 parts by weight, more preferably 90 to 300 parts by weight, and even more preferably 100 to 250 parts by weight. When the mixing ratio of the extender pigment is equal to or higher than the above lower limit, it is suitable in terms of imparting a natural texture and improving the painting workability. When the mixing ratio of the extender pigment is equal to or lower than the above upper limit, it is suitable in terms of imparting a natural texture, improving the painting workability, suppressing film cracking, etc.

[0026] The water-based topcoat can contain a coloring pigment. The coloring pigment is a component that contributes to the color development of the coating surface, and a desired color tone can be imparted to the coating surface by mixing the coloring pigments. Examples of the coloring pigment include titanium oxide, zinc oxide, carbon black, graphite, black iron oxide, iron-manganese composite oxide, iron-copper-manganese composite oxide, iron-chromium composite oxide, iron-chromium-cobalt composite oxide, copper-chromium composite oxide, copper-manganese-chromium composite oxide, copper-magnesium composite oxide, bismuth-manganese composite oxide, valve handle, molybdate orange, permanent red, permanent carmine, anthraquinone red, perylene red, quinacridone red, yellow iron oxide, titanium yellow, fast yellow, benzimidazolone yellow, chromium green, cobalt green, phthalocyanine green, ultramarine, navy blue, cobalt blue, phthalocyanine blue, quinacridone violet, dioxazine violet, aluminum pigment, pearl pigment, etc. These can be used alone or in combination of two or more. It is desirable that the average particle diameter of the coloring pigment is smaller than the average particle diameter of the aggregate. The average particle diameter of the coloring pigment is preferably 2 μm or less, more preferably 0.01 to 1 μm. The average particle diameter of the coloring pigment is a value measured by a laser diffraction particle size distribution measuring device.

[0027] When the water-based topcoat contains a coloring pigment, the mixing ratio of the coloring pigment can be 1 to 100 parts by weight in terms of solid content based on 100 parts by weight of the aggregate, preferably 2 to 80 parts by weight, more preferably 3 to 60 parts by weight, and still more preferably 4 to 40 parts by weight. When the mixing ratio of the coloring pigment is equal to or higher than the above lower limit, it is suitable in terms of color development, hiding power, etc. When the mixing ratio of the coloring pigment is equal to or lower than the above upper limit, it is suitable in terms of imparting a natural texture, suppressing film cracking, etc.

[0028] The aqueous topcoat material can also contain components other than those described above, as long as the effects of the present invention are not significantly impaired. Such components include, for example, thickeners, film-forming aids, leveling agents, wetting agents, plasticizers, antifreezing agents, pH adjusters, preservatives, fungicides, algicides, antibacterial agents, dispersants, antifoaming agents, adsorbents, fibers, water repellents, hydrophilizing agents, crosslinking agents, coupling agents, hydrophilic solvents, ultraviolet absorbers, light stabilizers, antioxidants, catalysts, and the like.

[0029] The aqueous topcoat material of the present invention can be produced by uniformly mixing the above-described aggregate, aqueous resin, hydrophobic solvent, and, if necessary, the above components and the like by a conventional method.

[0030] The viscosity of the aqueous topcoat material is preferably 5 to 150 Pa·s, more preferably 15 to 100 Pa·s, and even more preferably 25 to 75 Pa·s. When the aqueous topcoat material has such a viscosity, it is possible to ensure the coating workability of the aqueous topcoat material and enhance the effects such as improving the aesthetic appearance of the formed film. The viscosity mentioned here is the viscosity (pointer value at the fourth rotation) at 20 rpm measured with a BH-type viscometer at a temperature of 23°C.

[0031] [Film-forming method] In the present invention, for the surface to be coated, (1) a step of applying the aqueous topcoat material to form a coated surface; (2) a step of supplying water and / or a hydrophilic solvent to the coated surface and leveling the coated surface using a pressing tool; (3) a step of drying the coated surface are performed.

[0032] In the present invention, before the step (1), an undercoat material can be applied to form an undercoat film.

[0033] As the undercoat material, for example, those containing a binder and a pigment component can be used. Examples of the pigment component include coloring pigments, extender pigments, aggregates, and the like.

[0034] As the binder, various resins can be used. Examples of resin types include, for example, cellulose, polyvinyl alcohol, ethylene resin, vinyl acetate resin, polyester resin, alkyd resin, vinyl chloride resin, epoxy resin, acrylic resin, urethane resin, acrylic silicone resin, fluororesin, etc., or composite systems thereof, etc. These can be used alone or in combination of two or more. As the form of the binder, for example, water-soluble resin, water-dispersible resin (resin emulsion), solvent-soluble resin, solventless resin, non-aqueous dispersion resin, powder resin, etc. can be mentioned. Among these, water-soluble resin and / or water-dispersible resin is preferable, and in particular, an embodiment containing water-dispersible resin is suitable. By using water-soluble resin and / or water-dispersible resin, an aqueous undercoat material can be obtained. Also, these binders may be either those having crosslinking reactivity or those not having crosslinking reactivity. When a binder having crosslinking reactivity is used as the binder, the adhesion, durability, etc. of the film can be enhanced, the occurrence of problems such as cracks, peeling, swelling, etc. can be prevented, and the initial aesthetic appearance can be maintained over a long period of time.

[0035] Examples of coloring pigments include, for example, titanium oxide, zinc oxide, carbon black, graphite, black iron oxide, iron-manganese composite oxide, iron-copper-manganese composite oxide, iron-chromium composite oxide, iron-chromium-cobalt composite oxide, copper-chromium composite oxide, copper-manganese-chromium composite oxide, copper-magnesium composite oxide, bismuth-manganese composite oxide, valve handle, 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, navy blue, cobalt blue, phthalocyanine blue, quinacridone violet, dioxazine violet, aluminum pigment, pearl pigment, etc. These can be used alone or in combination of two or more. The average particle diameter of the coloring pigment is preferably 2 μm or less, more preferably 0.01 to 1 μm. The average particle diameter of the coloring pigment is a value measured by a laser diffraction particle size distribution measuring device.

[0036] Examples of extender pigments include heavy calcium carbonate, light calcium carbonate, kaolin, clay, potter's clay, china clay, diatomaceous earth, hydrated fine silica, talc, barite powder, barium sulfate, precipitated barium sulfate, barium carbonate, magnesium carbonate, silica powder, aluminum hydroxide, etc., and one or more of these can be used. The average particle diameter of the extender pigment is preferably less than 50 μm, more preferably 0.5 to 45 μm, and even more preferably 1 to 40 μm. The average particle diameter of the extender pigment is a value measured by a laser diffraction particle size distribution analyzer.

[0037] Examples of aggregates include ground materials such as marble, granite, serpentine, granite, fluorite, gypsum, feldspar, silica stone, silica sand, etc., ground porcelain materials, ground ceramic materials, ground glass materials, glass beads, ground resin materials, resin beads, metal grains, etc., or those with their surfaces coated with a colored coating. These can be used singly or in combination of two or more. The average particle diameter of the aggregate is preferably 0.05 to 3 mm, more preferably 0.06 to 1 mm. The average particle diameter of the aggregate is a value obtained by sieving using a metal mesh sieve specified in JIS Z8801-1:2000 and calculating the average value of its weight distribution.

[0038] The undercoat material preferably contains at least an extender pigment and / or an aggregate as a pigment component. When the undercoat material contains an extender pigment and / or an aggregate, a fine uneven structure is likely to be imparted to the surface of the undercoat film, which is suitable in terms of expressing the effects of the present invention. Further, when the undercoat material contains a coloring pigment, the undercoat film can be set to a desired color tone or can also be set to an approximate color of the topcoat material.

[0039] As the undercoat material, for example, an undercoat material with a pigment volume concentration of 20% or more can be used. By forming an undercoat film using such an undercoat material, the application work (coating or spreading) of the topcoat material in step (1) can be stably and efficiently performed, which is suitable in terms of improving aesthetic appearance. Such an effect is considered to be achieved by imparting a fine uneven structure to the surface of the undercoat film.

[0040] The pigment volume concentration of the undercoat material can be 20% or more, preferably 30 to 90%, more preferably 40 to 80%. The pigment volume concentration of the undercoat material is the volume percentage of the pigment component contained in the dry film of the undercoat material, and is a value obtained by calculation from the blending amounts of the binder and the pigment component constituting the undercoat material. The specific gravity of the binder is assumed to be 1.

[0041] The undercoat material can also contain components other than those described above as long as the effects of the present invention are not significantly impaired. Examples of such components include thickeners, film-forming aids, leveling agents, wetting agents, plasticizers, antifreezing agents, pH adjusters, antiseptics, fungicides, algicides, antibacterial agents, dispersants, defoaming agents, adsorbents, fibers, water repellents, hydrophilic agents, cross-linking agents, coupling agents, ultraviolet absorbers, light stabilizers, antioxidants, catalysts, and the like.

[0042] The undercoat material can be produced by uniformly mixing the above-described binder, pigment component, and, if necessary, each of the above components by a conventional method.

[0043] As the coating method of the undercoat material, for example, spray coating, roller coating, trowel coating, brush coating, etc. can be adopted. The coating amount of the undercoat material is preferably 0.05 to 1 kg / m 2 、more preferably 0.1 to 0.5 kg / m 2 is. Within such a range of coating amount, it is also possible to perform coating in multiple times. The coating or drying of the undercoat material is preferably carried out at room temperature (0 to 40°C).

[0044] When the pigment volume concentration of the undercoat material is 20% or more, the undercoat film formed by the undercoat material can be a matte film. In that case, the specular glossiness (measurement angle: 60 degrees) of the undercoat film is preferably 40 or less, more preferably 20 or less, still more preferably 10 or less, and particularly preferably 6 or less. Such an undercoat material is suitable in terms of improving the effects of the present invention. The specular glossiness of the undercoat film is obtained by applying the undercoat material to one side of a glass plate using a film applicator with a gap of 150 μm, placing the coated surface horizontally, drying it for 48 hours under standard conditions (air temperature: 23°C, relative humidity: 50%), and then measuring the specular glossiness at a geometric angle of 60 degrees using a specular gloss meter.

[0045] In the present invention, after performing coating or the like of the above-mentioned undercoat material on the surface to be coated as necessary, an aqueous topcoat material is applied as step (1). When using an undercoat material, it is desirable to apply the aqueous topcoat material after the undercoat film has dried.

[0046] In step (1), the above-mentioned aqueous topcoat material is applied to form a coated surface. That is, in step (1), the aqueous topcoat material is applied to the surface to be coated and spread to form a coated surface. When applying the aqueous topcoat material to the surface to be coated, for example, tools such as a spray, roller, brush, or spatula can be used. The application amount of the aqueous topcoat material is preferably 0.1 to 3 kg / m 2 , more preferably 0.2 to 2 kg / m 2 , still more preferably 0.3 to 1 kg / m 2 , particularly preferably 0.4 to 0.9 kg / m 2 . In the present invention, a coated surface with high aesthetic properties can be formed with a relatively small application amount, and the film can be made thinner and lighter.

[0047] When spreading the aqueous topcoat material, for example, tools such as a brush, spatula, or roller can be used. Among these, when using a brush, spatula, etc. to spread the aqueous topcoat material, a flat coated surface can be easily obtained by leveling the coated surface.

[0048] In the present invention, in step (1), it is desirable to form a coated surface using a squeegee. Specifically, it is desirable to use a squeegee, at least when spreading an aqueous topcoat material. It is more desirable to use a squeegee when applying the aqueous topcoat material to the surface to be coated and when spreading the aqueous topcoat material.

[0049] In the present invention, in step (2), water and / or a hydrophilic solvent (hereinafter also simply referred to as "water etc.") is supplied to the coated surface of the aqueous topcoat material, and the coated surface is leveled using a pressing tool. This step (2) can be performed on part or all of the coated surface obtained in step (1), and the supply of water etc. may be performed at least on the area leveled by the pressing tool.

[0050] To supply water etc. to the coated surface, for example, a method using means such as spraying, or a method of attaching water etc. to a pressing tool (for example, a squeegee, spatula, roller, etc.) can be adopted. In the latter case, the operation of supplying water etc. to the coated surface and the operation of leveling the coated surface can be performed simultaneously.

[0051] The type of water and / or hydrophilic solvent to be supplied to the coated surface may be appropriately selected according to the aqueous topcoat material to be used. As the hydrophilic solvent, for example, one or more selected from alcohol solvents, ether solvents, ester solvents, etc., whose solubility in water at 20°C is more than 10 g / 100 g H2O (preferably 20 g / 100 g H2O or more, more preferably ∞), can be used. In step (2), water, or a mixture of water and a hydrophilic solvent can preferably be used. The amount of water etc. to be supplied to the coated surface may be appropriately set in consideration of the drying property, aesthetic property, etc. of the coated surface.

[0052] The timing of supplying water etc. to the coated surface may be any time after step (1) and before the coated surface dries. Specifically, it is desirable to supply water etc. to the coated surface within 30 minutes (more preferably within 15 minutes) after the end of step (1) (after spreading the aqueous topcoat material).

[0053] As the pressing tool, for example, one or more selected from spatulas, spatulas, rollers, etc. can be used. When leveling the coated surface using the pressing tool, a method of gently pressing the coated surface with the pressing tool can be adopted. The operation of leveling the coated surface using the pressing tool can be performed on a part or the whole of the coated surface. Water or the like remaining on the coated surface may be removed as appropriate.

[0054] In step (3), the coated surface obtained by the above method is dried. The drying temperature is preferably 0°C or higher and 40°C or lower (room temperature), and heating can also be performed as necessary. The drying time is preferably 2 hours or longer.

[0055] By the above method, in the present invention, a film surface excellent in aesthetic appearance with a natural texture can be easily obtained. Further, in the present invention, the formed film surface can be flattened. For example, the entire formed film surface can be flattened, and when the film surface has various uneven patterns, a part thereof can also be flattened. The dry film thickness of such an aqueous topcoat film is preferably 0.03 to 2 mm, more preferably 0.05 to 1 mm, and still more preferably 0.1 to 0.5 mm.

[0056] In the present invention, the reason for achieving the above effects is not limited to the following, but when applying an aqueous topcoat material to form a coated surface, based on the characteristics of the aqueous topcoat material containing a hydrophobic solvent or the like, the penetration of water or the like supplied to the coated surface into the film is suppressed. As a result, it is considered that the water or the like on the coated surface can be utilized to efficiently perform leveling with a pressing tool, and moreover, film cracking caused by water or the like can be suppressed. In the present invention, it is considered that while an appearance having a natural texture is exhibited by the action of aggregates or the like, the aesthetic appearance is enhanced by the combined effects of the flattening effect and the crack suppression effect of the film.

[0057] In the present invention, after the above steps, a polishing step and / or a clear coating step can be performed.

[0058] The polishing process can be carried out for the purpose of improving the smoothness of the film surface and the like. The polishing process may be carried out by a known method using polishing cloth paper or the like. The particle size of the polishing cloth paper can be appropriately selected according to the desired smoothness. The treatment can also be carried out using two or more kinds of polishing cloth paper. Further, in the polishing process, polishing can be carried out while wetting the film surface with water or the like as necessary. The powder generated by polishing may be removed by air blowing or a waste cloth or the like.

[0059] The clear coating process can be carried out for purposes such as surface protection, improvement of weather resistance, improvement of stain resistance, and improvement of finish. Examples of the finishing material used for clear coating include clear finishing materials using acrylic resin, urethane resin, epoxy resin, acrylic silicone resin, fluororesin, etc. as binders. The clear finishing material may be either water-based or solvent-based, may be either colorless transparent or colored transparent, and may also be either with gloss or matte (including 70% gloss, 50% gloss, 30% gloss, etc.).

[0060] As the coating method of the clear finishing material, for example, various methods such as brush coating, spray coating, and roller coating can be adopted. The coating amount is preferably 0.01~0.5 kg / m 2 , more preferably 0.03~0.4 kg / m 2 . It is also possible to carry out coating in multiple portions within such a coating amount range.

Examples

[0061] Examples are shown below to make the features of the present invention clearer, but the present invention is not limited to these examples.

[0062] The following raw materials were used for the production of the topcoat. · Aggregate A: White silica sand (average particle size 150 μm) · Aggregate B: Gray silica sand (average particle size 100 μm) · Extender pigment A: Heavy calcium carbonate (average particle size 15 μm) · Extender pigment B: Heavy calcium carbonate (average particle size 28 μm) Extender pigment C: Talc (average particle size 8 μm) Water-based resin A: Acrylic resin emulsion (solid content 50% by weight, glass transition temperature 30°C) Water-based resin B: Alkoxysilyl group-containing acrylic resin emulsion (solid content 50% by weight, glass transition temperature 22°C) Hydrophobic solvent A: 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (solubility in water at 20°C: 0.04 g / 100 g H2O) Hydrophobic solvent B: Dipropylene glycol monobutyl ether (solubility in water at 20°C: 5g / 100gH2O) Hydrophilic solvent A: Ethylene glycol monobutyl ether (solubility in water at 20°C is infinite) Hydrophilic solvent B: Dipropylene glycol monopropyl ether (solubility in water at 20°C: 19 g / 100 g H2O) Color pigment A: Black pigment dispersion (20% by weight dispersion of carbon black (average particle size 0.05 μm)) Color pigment B: Yellow pigment dispersion (50% by weight dispersion of yellow iron oxide (average particle size 0.5 μm)) Color pigment C: Red pigment dispersion (50% by weight dispersion of red iron oxide (average particle size 0.2 μm)) Color pigment D: White pigment dispersion (60% by weight dispersion of titanium dioxide (average particle size 0.3 μm)) Fiber: inorganic fiber (average fiber length 0.1 mm) Antifreeze: Ethylene glycol Dispersant: Polycarboxylic acid dispersant Thickener: Hydroxyethyl cellulose 3% by weight aqueous solution Antifoaming agent: Silicone-based antifoaming agent

[0063] Example 1 For 100 parts by weight of aggregate A, 150 parts by weight of extender pigment A, 32 parts by weight of aqueous resin A (16 parts by weight in terms of solid content), 3 parts by weight of hydrophobic solvent A, 0.03 parts by weight of coloring pigment A, 0.03 parts by weight of coloring pigment B, 0.01 parts by weight of coloring pigment C, 11 parts by weight of coloring pigment D, 3 parts by weight of fiber, 1 part by weight of dispersant, 30 parts by weight of thickener, 10 parts by weight of water, and 1 part by weight of defoamer were mixed and stirred by a conventional method to produce topcoat material 1 (light gray, viscosity 48 Pa·s).

[0064] As the coated surface, a slate board pre-coated with a sealer was prepared. On this coated surface, light gray undercoat material 1 {an acrylic resin emulsion (resin specific gravity 1.0), titanium oxide (average particle diameter 0.3 μm, specific gravity 4.2), carbon black (average particle diameter 0.05 μm, specific gravity 1.8), talc (average particle diameter 8 μm, specific gravity 2.7), and heavy calcium carbonate (average particle diameter 5 μm, specific gravity 2.6) as the main components of an aqueous undercoat material. Pigment volume concentration 50%, specular gloss 2 (measurement angle 60 degrees)} was applied at a coating amount of 0.2 kg / m 2 using a wool roller, dried for 3 hours to form an undercoat film. Then, on this undercoat film, topcoat material 1 was applied with a putty knife, and immediately spread and leveled with a putty knife to form a coated surface (coating amount of topcoat material 1 0.6 kg / m 2 ). Then, water was sprayed onto the surface of the coated surface by atomization, the coated surface was leveled again with a putty knife, and then dried for 24 hours. By the above method, a light gray flat coated surface (dry film thickness 0.3 mm) was formed. No cracks were observed on the coated surface.

[0065] (Example 2) For 100 parts by weight of aggregate A, 120 parts by weight of extender pigment A, 28 parts by weight of aqueous resin A (14 parts by weight in terms of solid content), 3 parts by weight of hydrophobic solvent A, 0.2 parts by weight of coloring pigment A, 6 parts by weight of coloring pigment B, 10 parts by weight of coloring pigment C, 6 parts by weight of coloring pigment D, 3 parts by weight of fiber, 1 part by weight of dispersant, 30 parts by weight of thickener, 10 parts by weight of water, and 1 part by weight of defoamer were mixed and stirred by a conventional method to produce topcoat material 2 (dark orange, viscosity 46 Pa·s).

[0066] As the surface to be coated, a slate board pre-coated with a sealer was prepared. Onto this surface to be coated, an undercoat material 2 {aqueous undercoat material mainly composed of an acrylic resin emulsion (resin specific gravity 1.0), carbon black (average particle diameter 0.05 μm, specific gravity 1.8), yellow iron oxide (average particle diameter 0.5 μm, specific gravity 4.0), valve handle (average particle diameter 0.2 μm, specific gravity 5.0), titanium oxide (average particle diameter 0.3 μm, specific gravity 4.2), talc (average particle diameter 8 μm, specific gravity 2.7), and clay (average particle diameter 4 μm, specific gravity 2.6). Pigment volume concentration 58%, specular gloss 1.5 (measurement angle 60 degrees)} was applied at a coating amount of 0.2 kg / m 2 and was painted with a wool roller, dried for 3 hours to form an undercoat film. Next, onto this undercoat film, a topcoat material 2 was applied with a trowel, and immediately these were spread and leveled with a trowel to form a coated surface (coating amount of the topcoat material 2: 0.6 kg / m 2 ). Next, water was sprayed onto the surface of the coated surface with an atomizer, the coated surface was leveled again with a trowel, and then dried for 24 hours. By the above method, a dark orange flat film surface (dry film thickness 0.3 mm) was formed. No cracks were observed on the film surface.

[0067] (Example 3) To 100 parts by weight of aggregate A, 21 parts by weight of extender pigment A, 35 parts by weight of aqueous resin A (17.5 parts by weight in terms of solid content), 3 parts by weight of hydrophobic solvent A, 0.03 parts by weight of coloring pigment A, 0.03 parts by weight of coloring pigment B, 0.01 parts by weight of coloring pigment C, 11 parts by weight of coloring pigment D, 3 parts by weight of fiber, 1 part by weight of dispersant, 26 parts by weight of thickener, 14 parts by weight of water, and 1 part by weight of defoamer were mixed and stirred by a conventional method to produce a topcoat material 3 (light gray, viscosity 52 Pa·s).

[0068] When a film surface was formed in the same manner as in Example 1 using topcoat material 3 instead of topcoat material 1, a light gray flat film surface (dry film thickness 0.3 mm) was obtained. No cracks were observed on the film surface.

[0069] (Example 4) For 100 parts by weight of aggregate A, 100 parts by weight of extender pigment A, 20 parts by weight of aqueous resin A (10 parts by weight in terms of solid content), 3 parts by weight of hydrophobic solvent A, 0.03 parts by weight of coloring pigment A, 0.03 parts by weight of coloring pigment B, 0.01 parts by weight of coloring pigment C, 11 parts by weight of coloring pigment D, 3 parts by weight of fiber, 1 part by weight of dispersant, 30 parts by weight of thickener, 6 parts by weight of water, and 1 part by weight of defoamer were mixed and stirred by a conventional method to produce topcoat 4 (light gray, viscosity 46 Pa·s).

[0070] When topcoat 4 was used instead of topcoat 1 and a film surface was formed in the same manner as in Example 1, a light gray flat film surface (dry film thickness 0.3 mm) was obtained. No cracks were observed on the film surface.

[0071] (Example 5) For 100 parts by weight of aggregate A, 100 parts by weight of extender pigment A, 70 parts by weight of extender pigment B, 38 parts by weight of aqueous resin B (19 parts by weight in terms of solid content), 4 parts by weight of hydrophobic solvent B, 0.03 parts by weight of coloring pigment A, 0.03 parts by weight of coloring pigment B, 0.01 parts by weight of coloring pigment C, 11 parts by weight of coloring pigment D, 3 parts by weight of fiber, 1 part by weight of dispersant, 30 parts by weight of thickener, 6 parts by weight of water, and 1 part by weight of defoamer were mixed and stirred by a conventional method to produce topcoat 5 (light gray, viscosity 53 Pa·s).

[0072] When topcoat 5 was used instead of topcoat 1 and a film surface was formed in the same manner as in Example 1, a light gray flat film surface (dry film thickness 0.3 mm) was obtained. No cracks were observed on the film surface.

[0073] (Example 6) For 100 parts by weight of aggregate B, 110 parts by weight of extender pigment B, 20 parts by weight of extender pigment C, 16 parts by weight of aqueous resin A (8 parts by weight in terms of solid content), 2 parts by weight of hydrophobic solvent B, 0.1 parts by weight of coloring pigment B, 0.03 parts by weight of coloring pigment C, 38 parts by weight of coloring pigment D, 3 parts by weight of fiber, 0.5 parts by weight of antifreezing agent, 1 part by weight of dispersant, 38 parts by weight of thickener, and 1 part by weight of defoamer were mixed and stirred by a conventional method to produce topcoat 6 (light gray, viscosity 52 Pa·s).

[0074] When the topcoat material 6 was used instead of the topcoat material 1 and the coating surface was formed in the same manner as in Example 1, a light gray flat coating surface (dry film thickness: 0.3 mm) was obtained. No cracks were observed on the coating surface.

[0075] (Comparative Example 1) To 100 parts by weight of aggregate A, 210 parts by weight of extender pigment A, 35 parts by weight of aqueous resin A (17.5 parts by weight in terms of solid content), 3 parts by weight of hydrophilic solvent A, 0.03 parts by weight of coloring pigment A, 0.03 parts by weight of coloring pigment B, 0.01 parts by weight of coloring pigment C, 11 parts by weight of coloring pigment D1, 3 parts by weight of fiber, 1 part by weight of dispersant, 26 parts by weight of thickener, 14 parts by weight of water, and 1 part by weight of antifoaming agent were mixed and stirred by a conventional method to produce a topcoat material 7 (light gray, viscosity: 50 Pa·s).

[0076] When the topcoat material 7 was used instead of the topcoat material 1 and the coating surface was formed in the same manner as in Example 1, cracks were observed on the coating surface.

[0077] (Comparative Example 2) To 100 parts by weight of aggregate A, 210 parts by weight of extender pigment A, 35 parts by weight of aqueous resin A (17.5 parts by weight in terms of solid content), 3 parts by weight of hydrophilic solvent B, 0.03 parts by weight of coloring pigment A, 0.03 parts by weight of coloring pigment B, 0.01 parts by weight of coloring pigment C, 11 parts by weight of coloring pigment D1, 3 parts by weight of fiber, 1 part by weight of dispersant, 26 parts by weight of thickener, 14 parts by weight of water, and 1 part by weight of antifoaming agent were mixed and stirred by a conventional method to produce a topcoat material 8 (light gray, viscosity: 51 Pa·s).

[0078] When the topcoat material 8 was used instead of the topcoat material 1 and the coating surface was formed in the same manner as in Example 1, cracks were observed on the coating surface.

Claims

Claim 1 A method for forming a coating using an aqueous topcoat material, comprising: on a surface to be coated, (1) a step of applying the aqueous topcoat material to form a coated surface; (2) a step of supplying water and / or a hydrophilic solvent to the coated surface and leveling the coated surface using a pressing tool; (3) a step of drying the coated surface; wherein the aqueous topcoat material contains 3 to 30 parts by weight of an aqueous resin and 0.1 to 50 parts by weight of a hydrophobic solvent based on 100 parts by weight of an aggregate, and is characterized in that it is a coating formation method. Claim 2 The above hydrophobic solvent has a solubility in water at 20°C of 10 g / 100 g H ２ O or less, and the film-forming method according to claim 1, characterized in that. Claim 3 The coating formation method according to claim 1 or 2, characterized in that in the step (1), a coated surface is formed using a trowel. Claim 4 The coating formation method according to any one of claims 1 to 3, characterized in that in the step (2), the coated surface is leveled using a trowel.