Painted body

Abstract

To provide a coated body including a clear layer having transparency that does not conceal an underlying design and having calm massiveness with a mat feeling.SOLUTION: There is provided a coated body including a base material and at least two clear layers. The at least two clear layers each contain a light transmissive granular material having a median size (D50) of 10-200 μm. The amount of the light transmissive granular material contained in each of the clear layers is less than or equal to 35 mass %. The at least two clear layers each have an average film thickness of less than or equal to 80 μm.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a coated body, and more particularly to a coated body provided with a clear layer that has a transparency that does not hide the design of the base and has a matte finish and a calm, profound feel. [Background technology]

[0002] Paints are applied to exterior wall materials for buildings to impart design and weather resistance to the surface. Clear coatings that transmit visible light can make the most of the design of the base or substrate, and are often formed as a surface protective layer to protect the design surface. However, especially in recent years, values ​​regarding the exterior walls of houses have become more diverse, and a matte finish that suppresses gloss and gives a sense of calm and dignity has become more popular.

[0003] Japanese Patent Laid-Open Publication No. 2000-256578 (Patent Document 1) describes an invention for an architectural exterior wall panel in which a transparent or translucent synthetic resin-based paint containing aggregate with an average particle size of 30 to 100 μm dispersed therein is applied to the surface of the architectural exterior wall panel, the surface of which has been coated with a colored opaque paint, and the 60° specular gloss of the flat portion of the painted panel surface is in the range of 1 to 6. It is claimed that this makes it possible to provide an architectural exterior wall panel that can maintain a matte coating surface for a long period of time without causing the phenomenon of pigment precipitation from the coating surface (chalking).

[0004] Japanese Patent Application Laid-Open Publication No. 2005-187701 (Patent Document 2) describes an invention relating to a transparent water-based matte paint composition characterized by containing (A) a synthetic resin emulsion, (B) resin beads having a specific gravity of 1.0 or more and 1.5 or less, and (C) a wax having a specific gravity of 0.7 or more and less than 1.0. The invention relates to such a water-based matte paint composition that has excellent storage stability, is capable of suppressing uneven gloss in the formed coating film, has an excellent matte effect, and further provides excellent water resistance and transparency of the formed coating film.

[0005] Japanese Patent Publication No. 2013-208513 (Patent Document 3) describes an invention regarding a method for forming a matte multilayer film for ceramic building materials, in which an enamel coating film and a matte clear coating film are formed in that order on the ceramic building material, and the method uses a matte clear paint for ceramic building materials containing a specific ratio of light-transmitting granular material (a) having a median diameter (D50) of 2 to 10 μm, light-non-transmitting granular material (b) having a median diameter (D50) of 50 to 200 μm, and a binder resin (c). The invention states that this provides a method for forming a matte multilayer film for ceramic building materials that can suppress blocking without compromising transparency and that makes repaired areas less noticeable when repaired. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2000-256578 A [Patent Document 2] JP 2005-187701 A [Patent Document 3] JP 2013-208513 A Summary of the Invention [Problem to be solved by the invention]

[0007] Although Patent Documents 1 to 3 all describe techniques for suppressing the gloss of the surface of a coated body using a clear layer, the clear layer itself is a layer that is prone to becoming glossy, and therefore the matte effect of the clear layer cannot be said to be sufficient.

[0008] SUMMARY OF THE PRESENTLY PREFERRED EMBODIMENTS An object of the present invention is to provide a coated body having a transparent clear layer that does not hide the design of the base and has a matte finish and a calm, profound feel. [Means for solving the problem]

[0009] The present inventors have studied how to enhance the matte effect of the clear layer by using light-transmitting granular matter having a median diameter (D50) that is expected to provide a matte effect, and when the proportion of the light-transmitting granular matter contained in the clear layer was increased, the clear layer became cloudy and transparency was reduced. Next, instead of increasing the proportion of the light-transmitting granular matter contained in the clear layer, they studied whether the matte effect could be enhanced by thickening the clear layer, but there was a problem that the matte effect was reduced when the clear layer was thickened. It was confirmed that the matte effect tends to be reduced when the light-transmitting granular matter is painted in a thick film, because the light-transmitting granular matter is easily sunk into the paint film and the amount of light-transmitting granular matter present on the paint film surface is reduced. Therefore, the inventors discovered that by laminating two or more clear layers containing light-transmitting granules having a median diameter (D50) expected to provide a matte effect while reducing the proportion of light-transmitting granules contained in the clear layer and the film thickness of the clear layer, it is possible to provide a clear layer that maintains a transparency that does not conceal the design of the underlying layer, while also having a matte, calm, and heavy feel, and thus completed the present invention.

[0010] Therefore, the coated body of the present invention is a coated body comprising a substrate and at least two clear layers, each of the at least two clear layers containing light-transmitting granular material having a median diameter (D50) of 10 to 200 μm, the amount of the light-transmitting granular material contained in each clear layer being 35 mass% or less, and each of the at least two clear layers having an average film thickness of 80 μm or less.

[0011] In a preferred embodiment of the coated body of the present invention, the average film thickness of the at least two clear layers as a whole is 20 μm or more.

[0012] In another preferred embodiment of the coated body of the present invention, the 60 degree gloss value of the surface of the coated body is 20 or less.

[0013] In another preferred embodiment of the coated body of the present invention, at least one of the at least two clear layers contains light-impermeable particulate matter. Effect of the Invention

[0014] According to the present invention, it is possible to provide a coated body having a clear layer that has a transparency that does not hide the design of the base, and has a matte finish and a calm, heavy feel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The present invention is described in detail below. The present invention relates to a coated body comprising a substrate and at least two clear layers containing light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm, but the amount of the light-transmitting granular matter does not exceed 35 mass %. In this specification, this coated body is also referred to as the "coated body of the present invention."

[0016] In this specification, the painted body means a substrate having at least two clear layers coated on at least a part of its surface. In the present invention, the at least two clear layers may be directly formed on the substrate, or an additional layer such as a design layer may be present between the clear layer and the substrate, and the at least two clear layers may be formed on the substrate via the additional layer.

[0017] As used herein, substrate refers to an object onto which at least two clear layers are applied.

[0018] In this specification, the clear layer means a layer having a visible light transmittance of 5% or more, and the light transmittance of the clear layer is preferably 10% or more, and particularly preferably 15% or more. The clear layer may be a colorless layer or a colored layer. The coated body of the present invention contains light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm, but is a coated body having two or more clear layers in which the amount of the light-transmitting granular matter does not exceed 35 mass%, and may further have a clear layer other than the clear layer. For convenience, in this specification, "a clear layer containing light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm but in which the amount of the light-transmitting granular matter does not exceed 35 mass%" is also referred to as "a first clear layer," and "a clear layer other than the clear layer containing light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm but in which the amount of the light-transmitting granular matter does not exceed 35 mass%" is also referred to as "a second clear layer."

[0019] In this specification, the visible light transmittance means the total light transmittance in the visible region (360 nm to 750 nm), and can be measured in accordance with JIS K 7375:2008.

[0020] In this specification, the design layer means a layer intended to apply a design to a substrate. Here, the design is a shape, pattern, or color, or a combination of these. The substrate (particularly concrete, wood, etc.) can utilize its own design, but it is also possible to apply a design layer to the substrate. The design layer may be formed from, for example, paint or ink, or, when applying a design using wallpaper, film, etc., it is also possible to apply the design layer to the substrate by attaching these to the substrate.

[0021] As described above, the coated body of the present invention includes light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm, but has two or more clear layers (i.e., first clear layers) in which the amount of the light-transmitting granular matter does not exceed 35 mass %. By adjusting the average film thickness of each of the first clear layers constituting the coated body of the present invention so as not to exceed 80 μm, it is possible to form a clear layer that has a transparency that does not hide the design of the base, and has a calm and profound matte feel.

[0022] The coated body of the present invention may not include another layer between the first clear layers (i.e., the first clear layers are directly laminated to form a laminate structure), or may have a second clear layer between the first clear layers. However, the coated body of the present invention does not include a light-opaque layer between the first clear layers. In this specification, a light-opaque layer means a layer having a visible light transmittance of less than 5%.

[0023] In this specification, light-transmitting granular material means granular material having a visible light transmittance of 30% or more, and the light transmittance of the light-transmitting granular material is preferably 40% or more, and particularly preferably 50% or more.

[0024] The light-transmitting granular material is a material that can exhibit a matte effect while maintaining transparency, but the particle size is important for obtaining the matte effect. If the light-transmitting granular material is too large, it becomes difficult to obtain a matte finish, so the light-transmitting granular material used in the first clear layer has a median diameter (D50) of 10 to 200 μm, preferably 10 to 50 μm, and more preferably 10 to 20 μm. In addition, it is particularly preferable that the particle size of the light-transmitting granular material is approximately the same as the average film thickness of the first clear layer, or slightly smaller than the average film thickness of the first clear layer.

[0025] In this specification, the median diameter (D50) of the granular material is the 50% particle diameter (D 50) and can be obtained from the particle size distribution measured using a particle size distribution measuring device (for example, a laser diffraction / scattering particle size measuring device). Particle size is expressed as the sphere-equivalent diameter measured by the laser diffraction / scattering method.

[0026] The optically transparent granular material preferably has a specific gravity of 1.1 to 2.6.

[0027] Examples of the light-transmitting granular material include resin beads, glass beads, etc. The light-transmitting granular material may be used alone or in combination of two or more kinds.

[0028] The amount of light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm contained in each first clear layer constituting the coated body of the present invention is 35% by mass or less. If the amount of light-transmitting granular matter in each first clear layer is large, the clear layer becomes cloudy and tends to lose the transparency that does not hide the design of the base. In addition, the amount of light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm contained in the first clear layer is preferably 5 to 35% by mass, more preferably 7 to 30% by mass, and particularly preferably 10 to 25% by mass. From the viewpoint of ensuring a sufficient matte effect, the amount of the light-transmitting granular matter in the first clear layer is preferably 5% by mass or more. In addition, if the amount of the light-transmitting granular matter in the first clear layer exceeds 35% by mass, the extensibility of the clear layer decreases, and sufficient physical properties such as frost resistance and weather resistance may not be obtained.

[0029] The coated body of the present invention has at least two first clear layers, and the average thickness of each first clear layer is 80 μm or less. When the clear layer is formed by painting a thick film, the light-transmitting granular matter sinks into the clear layer, the amount of light-transmitting granular matter present on the surface of the clear layer decreases, and the matte effect tends to decrease, so the average thickness of each first clear layer is adjusted to 80 μm or less. The average thickness of the first clear layer is preferably 10 to 60 μm, and more preferably 20 to 50 μm.

[0030] In this specification, the average film thickness of the clear layer is a value determined by observing the cross section of the coating film with a scanning electron microscope or an optical microscope, and is calculated as the average value of the measurement results of 100 points randomly selected from the photographed image.

[0031] In the coated body of the present invention, the average thickness of the entire first clear layer is preferably 20 μm or more, more preferably 20 to 120 μm, and even more preferably 40 to 100 μm. By setting the average thickness of the entire first clear layer to 20 μm or more, it is possible to prevent water stains from occurring on the substrate. Water stains are a phenomenon in which water penetrates into the substrate when water is splashed on the coated body, causing the substrate to turn a wet color, and there is a problem that this can cause poor appearance due to rain after application and deterioration of the substrate. Although the clear layer itself is essentially water-resistant, there is a possibility that the barrier properties will be lost due to variations in thickness due to unevenness of the substrate and wear of the layer over time. For this reason, by setting the average thickness of the entire first clear layer to a certain level or more, specifically 20 μm or more, it is possible to stably maintain the barrier properties to water even after aging, and to suppress water stains. The average thickness of the entire first clear layer may be obtained by adding up the average thicknesses of the individual first clear layers, or may be obtained by directly measuring the average thickness of the entire first clear layer. In the coated body of the present invention, if the average film thickness of the entire first clear layer is less than 10 μm, the frost resistance may be poor when used as an exterior wall material in cold regions.

[0032] In the coated body of the present invention, it is preferable that the average film thickness of the first clear layer and the median diameter (D50) of the light-transmitting granules contained in the first clear layer satisfy the following relationship. (Relationship formula) 0.05< average film thickness / median diameter (D50) < 8 In the formula, the average film thickness is the average film thickness (μm) of the first clear layer, and the median diameter (D50) is the median diameter (D50) (μm) of the light-transmitting particulate matter contained in the first clear layer. In the first clear layer, if the value of the average film thickness / median diameter (D50) is too large, the matte appearance is lost, whereas if it is too small, matte performance may not be obtained. It is preferable that all of the first clear layers constituting the coated body of the present invention satisfy the above relational formula.

[0033] In the coated body of the present invention, at least one of the at least two first clear layers preferably contains a light-impermeable granular material. By using a light-impermeable granular material in the first clear layer, a higher matte finish can be obtained compared to a clear layer consisting only of a light-transmitting granular material. All of the first clear layers constituting the coated body of the present invention may contain a light-impermeable granular material.

[0034] In this specification, the term "light-impermeable granular material" refers to granular material having a visible light transmittance of less than 20%.

[0035] The median diameter (D50) of the light-opaque granular material is preferably 1 to 10 μm, more preferably 2 to 7 μm, and particularly preferably 3 to 6 μm.

[0036] The optically impermeable granular material preferably has a specific gravity of 1.1 to 4.5.

[0037] Examples of the light-opaque granular material include silica, calcium carbonate, silica, alumina, hydrated alumina, magnesia, talc, clay, barium sulfate, barium carbonate, wollastonite, ceramic powder, etc. The light-opaque granular material may be used alone or in combination of two or more kinds.

[0038] When the first clear layer contains light-opaque granular matter, the amount of the light-opaque granular matter contained in the first clear layer is preferably 0.1% by mass to 10% by mass, more preferably 0.5% by mass to 5% by mass. If the amount of the light-opaque granular matter is too large, the transparency of the coating film may be impaired and the viscosity of the paint may increase, resulting in reduced coating workability. In addition, if the light-opaque granular matter is silica, if the amount of the light-opaque granular matter is too large, the warm water resistance may be reduced.

[0039] In the coated body of the present invention, the first clear layer is preferably a coating film formed from an emulsion paint. The emulsion paint is a paint containing an emulsion resin, and the emulsion resin refers to a resin obtained by emulsion polymerization among water-dispersible resins. When the coated body of the present invention is a coated body that makes use of the design of the substrate, if the first clear layer is a coating film formed from an emulsion paint, the occurrence of wet color of the substrate can be suppressed. This is because, in the case of a resin dissolved in a medium, when applied to a substrate, the resin impregnates the substrate to the fine details and completely fills the voids, reducing light scattering and making the substrate darker overall (wet color), whereas in the case of an emulsion paint, the resin has a certain particle size, so it does not impregnate the substrate to the fine details compared to a dissolved resin, and the voids in the substrate can be left appropriately, which is thought to suppress the wet color.

[0040] In an emulsion paint that can be suitably used to form the first clear layer, the median diameter (D50) of the resin dispersed in the emulsion paint is, for example, 70 to 200 nm.

[0041] In this specification, the median diameter (D50) of the resin is the 50% particle diameter (D 50 ) and can be obtained from the particle size distribution measured using a particle size distribution measuring device (for example, a laser diffraction / scattering particle size measuring device). Particle size is expressed as the sphere-equivalent diameter measured by the laser diffraction / scattering method.

[0042] Furthermore, when the emulsion paint that can be suitably used to form the first clear layer is an acrylic resin-based emulsion paint, it is preferable that the monomers constituting the acrylic resin do not contain aromatic monomers such as styrene, or, even if they do contain aromatic monomers, the proportion of aromatic monomers is 5% by mass or less of the total constituent monomers. In order to form a clear layer, it is preferable not to use aromatic monomers such as styrene, which have poor weather resistance, as the constituent monomers of the acrylic resin. If the proportion of aromatic monomers such as styrene exceeds 5% by mass of the total constituent monomers, the weather resistance may be poor when used outdoors.

[0043] The 60-degree gloss value of the surface of the coated body of the present invention is preferably 20 or less, more preferably 1 to 20, even more preferably 2 to 15, and particularly preferably 3 to 10. The 60-degree gloss value is a gloss value for light with an incident angle of 60°, and is therefore an index of specular gloss when the surface of the coated body is viewed relatively from the front. The 85-degree gloss value of the surface of the coated body of the present invention is preferably 0.5 to 15, more preferably 1 to 10, and even more preferably 1.5 to 5. The 85-degree gloss value is a gloss value for light with an incident angle of 85°, and is therefore an index of specular gloss when the surface of the coated body is viewed relatively from a horizontal direction. The ratio of the 60-degree gloss value of the surface of the coated body of the present invention to the 85-degree gloss value (60-degree gloss value / 85-degree gloss value) is preferably 1 to 10, more preferably 1 to 7, and even more preferably 1 to 4. The smaller the 60 degree gloss value / 85 degree gloss value, the smaller the difference in appearance of the surface of the coated body when viewed from the front and when viewed from the horizontal direction.

[0044] In this specification, the surface of the coated body for which the gloss value is measured is a surface coated with at least two first clear layers and, if necessary, further layers. In this specification, the gloss value is the specular gloss specified in JIS K5600-4-7 (ISO 2813:1994), and can be measured, for example, using a gloss meter VG-2000 manufactured by Nippon Denshoku Co., Ltd.

[0045] In the coated body of the present invention, examples of the substrate include plastic substrates such as epoxy resin, ABS resin, polycarbonate, polyvinyl chloride, polystyrene, acrylic resin, particularly polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polypropylene (PP), etc.; metal substrates such as iron, stainless steel, aluminum, copper, titanium, and alloys thereof; inorganic substrates other than metals such as cement, concrete, gypsum, calcium silicate, calcium carbonate, marble, artificial marble, glass, ceramic, etc.; paper-based substrates, wood substrates, composite substrates combining two or more of these substrates, etc.

[0046] The shape of the substrate may be, for example, a film, a sheet, a plate, etc. The surface of the substrate may be smooth or may have irregularities.

[0047] Specific examples of the substrate include wood building materials such as veneer, plywood, particle board, and medium density fiberboard (MDF); ceramic building materials such as ceramic siding board, flexible board, calcium silicate board, gypsum slag barite board, wood chip cement board, asbestos cement board, pulp cement board, precast concrete board, lightweight aerated concrete (ALC) board or ALC panel, and gypsum board; various building materials (particularly building boards) such as metal siding board, and metal building materials such as aluminum, iron, and stainless steel. Specific examples of the substrate include plastic substrates such as PVC sheet, tarpaulin, plastic cardboard, and acrylic board, coated paper (specifically resin-coated paper), art paper, cast paper, lightly coated paper, fine paper, synthetic paper, and inkjet paper; tiles, glass plates, and the like.

[0048] The surface of the substrate may be subjected to pretreatment such as degreasing, chemical conversion treatment, and polishing, or may be coated with a sealer or primer. For example, when the substrate is a substrate (particularly a porous substrate) that may excessively absorb paint or ink, such as a ceramic building material, the surface of the substrate may be coated with a sealer and a sealer layer may be formed on the substrate. Also, when the substrate is a metal building material, the surface of the substrate may be coated with a primer and a primer layer may be formed on the substrate.

[0049] In the coated body of the present invention, the layer in contact with the substrate preferably contains a glycidyl group. The glycidyl group present in the layer in contact with the substrate can improve adhesion to the substrate. For example, by forming a coating film using a resin having a glycidyl group, it is possible to form a layer containing a glycidyl group, particularly a layer containing a resin having a glycidyl group, on the substrate.

[0050] In the coated body of the present invention, a sealer layer may be formed between the substrate and the first clear layer. In one embodiment of the coated body of the present invention, the coated body may include a substrate, a sealer layer, and at least two first clear layers. Here, the sealer layer is located on the substrate, and the first clear layer is located on the sealer layer. A sealer known in the paint industry can be used to form the sealer layer. In addition, when the coated body further includes a design layer, the design layer may be disposed between the substrate and the sealer layer, or between the sealer layer and the first clear layer.

[0051] In addition, in cases where a sealer layer is required when painting a substrate, it is preferable to further form a water-repellent layer from the viewpoint of suppressing the occurrence of water stains due to the clear layer. In one embodiment of the coated body of the present invention, the coated body can include a substrate, a sealer layer, a water-repellent layer, and at least two first clear layers. Here, the sealer layer is located on the substrate, the water-repellent layer is located on the sealer layer, and the first clear layer is located on the water-repellent layer. In addition, in cases where the coated body further includes a design layer, the design layer can be disposed between the substrate and the sealer layer, or between the water-repellent layer and the first clear layer. Here, the water-repellent layer is a layer containing a water-repellent agent such as a silicone-based water-repellent agent, and the contact angle of the water-repellent layer after painting is preferably 70 degrees or more.

[0052] In this specification, the contact angle of the water-repellent layer refers to the contact angle between the water-repellent layer surface and water measured by the static drop method. Specifically, 10 μL of distilled water is dropped onto the water-repellent layer surface, and the surface is left to stand for 10 seconds under an atmosphere of 20° C., and the contact angle between the water-repellent layer surface and water is measured using a general contact angle meter (e.g., Kyowa Interface Science Co., Ltd. Contact Angle Meter DMs-401).

[0053] In the coated body of the present invention, at least two first clear layers may have further layers such as a photocatalyst layer, a second clear layer, and an overcoat layer formed thereon. In one embodiment of the coated body of the present invention, the coated body may include a substrate, at least two first clear layers, and at least one further layer selected from a photocatalyst layer, a second clear layer, and an overcoat layer. Here, the first clear layer is located on the substrate, and the further layer is located on the first clear layer. In addition, at least one further layer selected from a sealer layer, a water-repellent layer, a design layer, and the like as described above may be disposed between the substrate and the first clear layer.

[0054] The photocatalyst layer is a layer containing a material that exhibits photocatalytic activity when irradiated with light such as sunlight. Examples of materials that exhibit photocatalytic activity include metal oxides such as anatase-type titanium oxide, rutile-type titanium oxide, tin oxide, zinc oxide, and cerium oxide, but are not limited to these materials. In addition, the overcoat layer usually refers to a layer that is applied to the outermost surface (in other words, a layer that is disposed at a position farthest from the substrate), but in this specification, when the coated body of the present invention has an additional layer on the first clear layer, and the layer applied to the outermost surface at that time is a layer other than the photocatalyst layer or the second clear layer, the layer disposed on the outermost surface is referred to as the overcoat layer. The average film thickness of the overcoat layer is usually several μm or less, for example, about 0.1 to 1 μm.

[0055] Next, a coating composition suitable for use in forming the first clear layer will be described in detail. In this specification, this coating composition is also referred to as a "coating composition for the first clear layer."

[0056] The coating composition for the first clear layer contains a water-dispersible resin and a light-transmitting granular material, and preferably further contains a light-impermeable granular material. The light-transmitting granular material and the light-impermeable granular material are as described above.

[0057] In this specification, the term "water-dispersible resin" refers to a resin capable of distributing in water to form a heterogeneous system (e.g., an emulsion or suspension). The water-dispersible resin preferably contains an emulsion resin. The emulsion resin is a water-dispersible resin that can have a large molecular weight and has excellent dispersion stability. The water-dispersible resin is preferably contained in the coating composition so that the amount of the water-dispersible resin in the first clear layer is 30 to 95% by mass. The amount of the water-dispersible resin in the first clear layer is more preferably 40 to 90% by mass, and further preferably 50 to 85% by mass. The water-dispersible resin may be used alone or in combination of two or more kinds.

[0058] The water-dispersible resin preferably contains a water-dispersible resin containing an acrylic component as a constituent element (repeating unit, etc.). In this specification, the term "acrylic component" refers to acrylic acid, methacrylic acid and derivatives thereof (for example, compounds having a (meth)acryloyl group such as esters and amides of acrylic acid and methacrylic acid, acrylic acid nitrile, methacrylic acid nitrile, etc.). The acrylic component may be used alone or in combination of two or more kinds.

[0059] In this specification, the term (meth)acryloyl means methacryloyl or acryloyl. In addition, in this specification, the term (meth)acrylate means methacrylate or acrylate. For example, 2-ethylhexyl (meth)acrylate is 2-ethylhexyl acrylate or 2-ethylhexyl methacrylate. In addition, a prefix indicating a plurality of (meth)acrylates may be added to (meth)acrylates, such as di(meth)acrylate, tri(meth)acrylate, etc., and in this case, each (meth)acrylate may be the same or different.

[0060] The water-dispersible resin containing an acrylic component as a constituent element includes, in addition to acrylic resin, various modified resins such as acrylic styrene resin, acrylic silicone resin, fluorine-modified acrylic resin, fatty acid-modified acrylic resin, urethane-modified acrylic resin, and epoxy-modified acrylic resin.

[0061] The water-dispersible resin may contain a non-acrylic component as a constituent element (repeating unit, etc.). The non-acrylic component is a component other than the acrylic component, and examples thereof include, in addition to styrene, carboxyl group-containing monomers such as fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, crotonic acid, and vinyl versatic acid; aromatic monomers such as methylstyrene, chlorostyrene, methoxystyrene, and vinyltoluene; olefin monomers such as ethylene and propylene; vinyl monomers such as vinyl acetate and vinyl chloride; amide monomers such as maleic acid amide; alkoxysilyl group-containing monomers such as vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, and vinylmethyldiethoxysilane; dialkyl fumarate, allyl alcohol, vinylpyridine, and butadiene.

[0062] The water-dispersible resin can be obtained by polymerization of monomer components as constituent elements, and is preferably obtained by emulsion polymerization of the monomer components as constituent elements. The monomer components may be used alone or in combination of two or more.

[0063] The coating composition for the first clear layer may further contain at least one selected from the group consisting of an ultraviolet absorber and a radical scavenger.

[0064] The ultraviolet absorbent has the effect of absorbing ultraviolet rays and preventing deterioration caused by ultraviolet rays. Examples of the ultraviolet absorbent include benzophenone-based ultraviolet absorbents, benzoate-based ultraviolet absorbents, benzotriazole-based ultraviolet absorbents, triazine-based ultraviolet absorbents (particularly hydroxyphenyltriazine-based ultraviolet absorbents), and benzylidene camphor-based ultraviolet absorbents. The ultraviolet absorbent may be used alone or in combination of two or more.

[0065] Examples of the ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone-2-hydroxy-4-benzyloxybenzophenone, bis(5-benzoyl-4-hydroxy-2-methoxyphenyl)methane, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4, 4'-Dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-[2'-hydroxy-3',5'-bis(α,α-(dimethylbenzyl)phenyl]benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenzo Triazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-amylphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, 2,2'-methylene-bis[4-(1,1,3,3-tetramethylbutyl)-6-(2N-benzotriazol-2-yl)phenol], methyl-3-[3-t-butyl-5-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]phenol, 2-(2-hydroxyphenyl)propionate and polyethylene glycol condensation products, 2-(2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2,6-di-t-butylphenyl-3',5'-di-t-butyl-4'-hydroxybenzoate, hexadecyl-3,5-di-t-butyl-4-hydroxybenzoate, 2-[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-(2'-ethyl)hexyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine, hydroxyphenyl triazine, 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-triazine, and the like.

[0066] The radical scavenger can capture free radicals and improve light stability. In the present invention, the radical scavenger also includes a substance (so-called polymerization inhibitor) that reacts with free radicals and has a function of preventing polymerization reaction from occurring. The radical scavenger may be used alone or in combination of two or more kinds.

[0067] Examples of the radical scavenger include hindered amine compounds, hydroquinone compounds, phenol compounds, phenothiazine compounds, nitroso compounds, and N-oxyl compounds, and hindered amine light stabilizers (HALS) are particularly preferred.

[0068] Examples of the radical scavenger include hindered amine compounds such as bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, 1-{2-(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy)ethyl}-2,2,6,6-tetramethylpiperidine, and 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro{4.5}decane-2,4-dione; phenols; and o-, m-, or p-cresols. phenolic compounds such as 2-t-butyl-4-methylphenol, 6-t-butyl-2,4-dimethylphenol, 2,6-di-t-butyl-4-methylphenol, 2-t-butylphenol, 4-t-butylphenol, 2,4-di-t-butylphenol, 2-methyl-4-t-butylphenol, 4-t-butyl-2,6-dimethylphenol, hydroquinone, hydroquinone monomethyl ether, methylhydroquinone, 2,5-di-t-butyl Hydroquinone compounds such as 4-methylbenzcatechin, t-butylhydroquinone, 3-methylbenzcatechin, 2-methyl-p-hydroquinone, 2,3-dimethylhydroquinone, trimethylhydroquinone, t-butylhydroquinone, benzoquinone, t-butyl-p-benzoquinone, and 2,5-diphenyl-p-benzoquinone; phenothiazine compounds; nitroso-based compounds such as N-nitroso-N-phenylhydroxylamine ammonium and N-nitroso-N-phenylhydroxylamine aluminum salt; and N-oxyl-based compounds such as 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl, 4-oxo-2,2,6,6-tetramethyl-piperidine-N-oxyl, and 4-methoxy-2,2,6,6-tetramethyl-piperidine-N-oxyl.

[0069] The first clear layer coating composition is preferably a water-based coating composition. In this specification, the term "water-based coating composition" refers to a coating composition containing water as a main solvent. The water is not particularly limited, but preferred examples include pure water such as ion-exchanged water and distilled water. In addition, when the coating composition is to be stored for a long period of time, water sterilized by ultraviolet irradiation or the like may be used to prevent the growth of mold and bacteria. In the first clear layer coating composition, the amount of water is preferably 20 to 80% by mass, more preferably 30 to 70% by mass.

[0070] The coating composition for the first clear layer preferably has an ultraviolet ray transmittance of less than 30%, more preferably less than 20%, and even more preferably less than 10%, when a film having a thickness of 10 μm is formed.

[0071] In this specification, ultraviolet transmittance means the transmittance of light in the wavelength range from 280 nm to 400 nm, and can be measured using a spectrophotometer. Specifically, the coating composition is applied to quartz glass so that the dry film thickness is 10 μm, and then dried in a drying oven at 80°C for 10 minutes to prepare a sample for measurement. The ultraviolet transmittance of the sample can then be measured using a UV-visible spectrophotometer (e.g., Shimadzu UV-2450).

[0072] Other components that can be appropriately blended into the first clear layer coating composition depending on the purpose include other resins, solvents, pigments, surface conditioners, wetting agents, dispersants, thickeners, anti-settling agents, anti-skinning agents, anti-sagging agents, defoamers, color separation inhibitors, viscosity adjusters, rheology control agents, leveling agents, defoamers, drying agents, plasticizers, preservatives, anti-fungal agents, antibacterial agents, insecticides, antiviral agents, antistatic agents, and conductivity imparting agents.

[0073] The first clear layer coating composition can be prepared by mixing various components appropriately selected as necessary. The first clear layer coating composition can be either one-component or two-component, but in the case of a two-component coating composition, the base agent and the curing agent are prepared in advance and mixed at the time of painting. Usually, the base agent contains a resin, and the curing agent contains a crosslinking agent. When mixing the base agent and the curing agent, additives such as water or a diluent may be further added for the purpose of adjusting the viscosity.

[0074] The first clear layer coating composition has a viscosity of 1 to 1000 (Pa s, 23°C) at a shear rate of 0.1 (1 / s), and preferably has a viscosity of 0.05 to 10 (Pa s, 23°C) at a shear rate of 1000 (1 / s). In this specification, the viscosity is measured using a rheometer (e.g., ARES rheometer manufactured by TA Instruments) after adjusting the liquid temperature to 23°C.

[0075] The means for applying the coating composition for the first clear layer is not particularly limited, and known coating means such as brush coating, roller coating, trowel coating, spatula coating, flow coater coating, and spray coating (e.g., air spray coating, airless spray coating), can be used.

[0076] The drying method of the first clear layer coating composition is not particularly limited, and may be either natural drying at ambient temperature or forced drying using a dryer, etc., but forced drying is preferable when the first clear layer coating composition contains a resin with a high glass transition temperature. When the first clear layer coating composition contains a resin containing a monomer whose homopolymer Tg is 50°C or higher as a component, it is preferable to heat-dry the coating composition at 80 to 150°C after coating. EXAMPLES

[0077] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples in any way.

[0078] <Clear paint 1> 70 parts by mass of water-based resin A was added to a mixer in terms of solid content, and 20 parts by mass of light-transmitting granular material A (PMMA resin beads, particle diameter: 12 μm) in terms of solid content, 3.5 parts by mass of silica (median diameter (D50): 5 μm) in terms of solid content, and a total of 6.5 parts by mass of thickener, dispersant, UV absorber, and light stabilizer as additives in terms of solid content were gradually added under stirring, and stirred for 20 minutes to prepare clear paint 1.

[0079] <Clear paint 2~14> Similarly to the preparation method of the above-mentioned clear coating 1, clear coatings 2 to 14 were prepared according to the formulations shown in the following Tables 1 to 3. Note that the amount of silica in the clear coating 11 was extremely large, so the viscosity was high and painting was difficult, and therefore the painted body was not evaluated.

[0080] The materials used in the preparation of clear coating materials 1 to 14 shown in Tables 1 to 3 are as follows. Water-based resin A: Styrene acrylic emulsion, solid content 43% by mass, styrene (St) content 10% by mass Water-based resin B: Acrylic emulsion, solid content 50% by mass, St amount 0% by mass Water-based resin C: Acrylic silicone emulsion, solid content 43% by mass, St amount 13% by mass Water-based resin D: Acrylic emulsion, solid content 45% by mass, St amount 0% by mass Water-based resin E: Styrene acrylic emulsion, solid content 48% by mass, St amount 29% by mass Water-based resin F: Styrene acrylic emulsion, solid content 40% by mass, St amount 39% by mass Water-based resin G: Styrene acrylic emulsion, solid content 40% by mass, St amount 49% by mass Water-based resin H: Styrene acrylic emulsion, solid content 47% by mass, St amount 59% by mass Water-based resin I: Acrylic fluorine emulsion, solid content 51% by mass, St amount 59% by mass ·Light-transparent particles A: PMMA resin beads manufactured by Sekisui Plastics Co., Ltd., median diameter (D50) 5 μm, solid content 100% by mass, visible light transmittance 90%, specific gravity 1.2 ·Light-transparent particles B: PMMA resin beads manufactured by Sekisui Plastics Co., Ltd., median diameter (D50) 12 μm, solid content 100% by mass, visible light transmittance 90%, specific gravity 1.2 ·Light-transparent granules C: PMMA resin beads manufactured by Sekisui Plastics Co., Ltd., median diameter (D50) 80 μm, solid content 100% by mass, visible light transmittance 90%, specific gravity 1.2 Light-transmitting granules D: PMMA resin beads manufactured by Nippon Exlan Kogyo Co., Ltd., median diameter (D50) 150 μm, solid content 100% by mass, visible light transmittance 90%, specific gravity 1.2 ·Light-transparent granules E: PMMA resin beads manufactured by Sekisui Plastics Co., Ltd., median diameter (D50) 200 μm, solid content 100% by mass, visible light transmittance 90%, specific gravity 1.2 Light-opaque granular material A: WR Grace silica, particle size 5 μm, solid content 100% by mass, specific gravity 1.8 Thickener: ADEKA polyether polyol urethane polymer, solid content 52% by weight Dispersant: San Nopco special polycarboxylate ammonium salt aqueous solution, solids content 19% by weight UV absorber: BASF, solid content 41% by weight Light stabilizer: BASF, solid content 100% by weight

[0081] In addition, the numbers shown in columns such as "Total of resins" and "Total of light-transmitting granular matter" in Tables 1 to 3 represent the mass parts of each component in the paint solids, but for painted bodies prepared according to the painted body preparation examples described below, the numbers here can be regarded as the mass parts of each component per 100 mass parts of the first clear layer.

[0082] [Table 1]

[0083] [Table 2]

[0084] [Table 3]

[0085] <Example of the creation of a painted body with a clear layer on the surface> The cement-based substrate surface was coated with a clear coating by air spray to a predetermined thickness, and dried at 80°C for 5 minutes to form a clear layer. In this way, the coated bodies of Comparative Examples 1 to 3 and 6 to 9 were produced. Details of the clear coating specifications are shown in Tables 4 and 6.

[0086] <Example of preparation of a test specimen for measuring the transmittance of a painted body having a clear layer on the surface> A clear coating prepared to a predetermined thickness was applied to the surface of the quartz glass plate by air spraying, and the clear coating was dried at 80°C for 5 minutes to form a clear layer. In this way, test specimens for measuring transmittance were prepared for Comparative Examples 1 to 3 and 6 to 9. Details of the clear coating specifications are shown in Tables 4 and 6.

[0087] <Example of the creation of a painted body with two or more clear layers on the surface> A clear coating material prepared to a predetermined thickness was applied to the surface of the cement-based substrate by air spraying, and dried at 80°C for 5 minutes to form a first clear layer. Next, a coating material for a second clear layer was applied to the first clear layer by air spraying to a predetermined thickness, and dried at 80°C for 5 minutes to form a second clear layer. In this way, the coated bodies of Examples 1 to 12 and the coated bodies of Comparative Examples 4, 5, and 11 to 13 were produced. Details of the clear coating specifications are shown in Tables 4 to 8. In the preparation of the coated bodies in Comparative Examples 11 to 13, the layers formed had low visible light transmittance and could not actually be called clear layers.

[0088] <Example of preparation of a test specimen for measuring the transmittance of a painted body having two or more clear layers on the surface> A clear coating material prepared to have a predetermined thickness was applied to the surface of the quartz glass plate by air spraying, and dried at 80°C for 5 minutes to form a first clear layer. Next, a coating material for a second clear layer was applied to the first clear layer by air spraying to have a predetermined thickness, and dried at 80°C for 5 minutes to form a second clear layer. In this way, transmittance measurement specimens of Examples 1 to 12 and transmittance measurement specimens of Comparative Examples 4, 5, and 11 to 13 were prepared. Details of the clear coating specifications are shown in Tables 4 to 8.

[0089] <Coating film properties: gloss> The 60 degree gloss value and 85 degree gloss value of the produced coated body were measured using a gloss meter VG-2000 manufactured by Nippon Denshoku Co., Ltd., and the 60 degree gloss value / 85 degree gloss value ratio was calculated. The results are shown in Tables 4 to 8.

[0090] <Coating film properties: Visible light transmittance> The visible light transmittance of the test specimen for transmittance measurement was measured using an ultraviolet / visible / near-infrared spectrophotometer UV-3600 Plus manufactured by Shimadzu Corporation. The results are shown in Tables 4 to 8.

[0091] <Water stain evaluation> The prepared coated bodies were immersed in room temperature water for 5 minutes, and then the condition of the coated body surface was observed and evaluated for water stains according to the following evaluation criteria. The results are shown in Tables 4 to 8. (Evaluation Criteria) ○: No change in appearance before and after immersion △: Wet color occurs on the substrate in an area of ​​1% or less. ×: Wet color occurs on the substrate over an area of ​​1% or more.

[0092] <Warm water resistance evaluation> The prepared coated bodies were immersed in hot water at 60°C for 10 days, and the surface condition of the coated bodies was visually observed and the hot water resistance was evaluated according to the following evaluation criteria. In order to evaluate the hot water resistance, the coated bodies were taken out after immersion, the water on the surface was wiped off with a cloth, and ΔE was measured with a color difference meter. The results are shown in Tables 4 to 8. (Evaluation Criteria) ○: No color change occurred in the coating film before and after evaluation (ΔE≦0.2) △: After evaluation, the coating film turned slightly white (0.2<ΔE≦0.5) ×: After evaluation, the coating film turned white (0.5<ΔE)

[0093] <Freeze-thaw method B test> The coated bodies were subjected to a total of 200 cycles of testing, with one cycle being -20°C deep in the substrate in an air environment, followed by 10°C deep in an underwater environment. After the tests, the condition of the coated body surface was visually observed, and the resistance to freeze-thawing was evaluated according to the following evaluation criteria. The results are shown in Tables 4 to 8. (Evaluation Criteria) ○: No abnormalities such as cracks or peeling occurred on the substrate or coating before and after evaluation △: After evaluation, small cracks or slight peeling was observed on the substrate or coating. ×: After evaluation, clear cracks or peeling was observed on the substrate or coating film.

[0094] <Visual appearance; transparency> The prepared coated bodies were visually observed, and the transparency of the coated body surface was evaluated according to the following evaluation criteria. The results are shown in Tables 4 to 8. (Evaluation Criteria) ◯: The clear layer has excellent transparency, and even after painting the clear layer, the finished appearance makes the most of the design of the base material. ×: The substrate can be seen from the surface of the clear layer, but the clear layer has poor transparency, and the design of the substrate is impaired. ××: The base material cannot be confirmed.

[0095] <Visual appearance; solid feel> The prepared coated bodies were visually observed, and the solid feel of the coated body surface was evaluated according to the following evaluation criteria. The results are shown in Tables 4 to 8. (Evaluation Criteria) ○: When observed in the morning, afternoon, and evening on sunny and cloudy days, the finish has a matte, calm, and heavy feel from any angle. ×: Observed in the morning, afternoon, and evening on sunny and cloudy days. Under some conditions, depending on the angle, there was some shine and glitter, and the texture was impaired. It cannot be said to have a heavy feel. ××: There is shine and glitter, and the texture is lost. Or the base material is glittering. It cannot be said to have a solid feel.

[0096] <Accelerated weather resistance evaluation (SUV)> The prepared coated bodies were subjected to an accelerated weather resistance test for 800 hours under the following test conditions using an SUV-W261 manufactured by Iwasaki Electric Co., Ltd. (Test conditions) Irradiation wavelength range: 295-450nm, UV intensity on painted surface: 100mW / cm 2 ±5% During irradiation: Humidity 50% RH Black panel temperature 63℃±2℃ Condensation: 95% RH or more Black panel temperature 40℃±2℃ Test conditions: 6 hours of irradiation / 2 hours of condensation After the test, the coated body was dried at 50°C for 16 hours, and then ΔE was measured using a color difference meter. The results are shown in Tables 4 to 8.

[0097] [Table 4]

[0098] [Table 5]

[0099] [Table 6]

[0100] [Table 7]

[0101] [Table 8]

Claims

1. A coated body having a substrate and at least two clear layers, Each of the at least two clear layers contains light-transmitting granular matter having a median diameter (D50) of 10 to 200 μm, and the amount of the light-transmitting granular matter contained in each clear layer is 7% by mass or more and 35% by mass or less; The at least two clear layers each have an average film thickness of 80 μm or less, A coated body, characterized in that the average film thickness of the at least two clear layers as a whole is 20 μm or more.

2. 2. The coated body according to claim 1, characterized in that the 60 degree gloss value of the surface of the coated body is 20 or less.

3. A coated body as described in claim 1 or 2, characterized in that the 85 degree gloss value of the surface of the coated body is 0.5 to 15.

4. 3. The coated body according to claim 1, wherein at least one of the at least two clear layers contains light-impermeable particles.

5. The ratio of the 60-degree gloss value to the 85-degree gloss value on the surface of the coated body (60-degree gloss 3. The coated body according to claim 1 or 2, characterized in that the gloss value (gloss value / 85 degree gloss value) is 1 to 10.

Images