Building material with coating film and method for manufacturing the same

Abstract

To provide a building material which gives appearance having clearly different color tones to a design part and a decorative groove with a less step, while using a gelatinous particle-containing aqueous coating material, has three-dimensional feeling, and gives high grade appearance.SOLUTION: A method for manufacturing a building material with a coating film coats a decorative groove with an aqueous coating material (M) without curing a design part 10, scrapes the aqueous coating material (M) attached to the design part 10 before the aqueous coating material (M) is dried, and coats the design part 10 with the aqueous coating material (H) in a state in which a groove bottom of the decorative groove is cured, after the coating film of the aqueous coating material (M) is dried, wherein the design part 10 includes a large number of fine projections 50, the aqueous coating material (M) contains gelatinous particles (X) containing gelatinous particles (X1), optionally, gelatinous particles (X2), and the aqueous coating material (H) contains gelatinous particles (Y) containing gelatinous particles (Y1) having a color difference ΔE*ab between the gelatinous particles (X1) and the gelatinous particles (Y1) of 5 or less, and gelatinous particles (Y2) having a color difference ΔE*ab between the gelatinous particles (X1) and the gelatinous particles (Y2) of 30 or more.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a coating-coated building material and a method for producing the same. [Background technology]

[0002] Conventionally, the exterior walls of buildings have generally been made of flat building materials with a single-color enamel paint coating applied to the entire surface. In recent years, in order to give the design of building exterior walls and other surfaces a more dignified appearance, decorative grooves have been applied to the surface of the building material to be painted, giving the area other than the decorative groove (the design part) height and enhancing the three-dimensional effect. When applying decorative grooves, it is required to create a design that emphasizes the outline of the design part by changing the color tone from the design part.

[0003] However, in order to achieve an appearance in which the design part and the decorative groove have different color tones, it was necessary to first cure the design part, then apply the primer paint and top coat paint for the decorative groove, and then, after the paint for the decorative groove had dried, cure the decorative groove and then apply the primer paint and top coat paint for the design part. This poses a problem as it requires more man-hours than the conventional method of painting the entire surface of a flat exterior wall with a single color paint. Therefore, there is a demand for a method to change the color tone of the design part and decorative groove with fewer man-hours.

[0004] Patent Document 1 discloses an invention for making the design portion and the decorative groove have different color tones with a small number of steps. Patent Document 1 discloses a finishing method in which a primer paint that forms the color of the recesses is applied to the entire surface, then a paint of a color different from the color of the recesses is applied with a roller only to the protruding parts, and finally a clear paint containing 40 to 210 μm plastic powder and 1 to 5 wt % colored particles is applied to the entire surface of the object to be coated. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-039681 Summary of the Invention [Problem to be solved by the invention]

[0006] The method of Patent Document 1 allows for the color tone of the design portion and the decorative groove to be changed, resulting in a somewhat three-dimensional appearance. However, in recent years, there has been a demand for even more sophisticated designs. Therefore, the inventors focused on water-based paints containing gel particles (hereinafter also referred to as "gel particle-containing water-based paints"), which can produce more sophisticated designs than enamel paints. Water-based paints containing gel particles can form a scattered patterned coating film with a single coat, and also produce a more three-dimensional coating film than enamel paints.

[0007] Here, the gel particle-containing water-based paint coating film will be explained using Figure 11. As shown in Figure 11, a coating film 90 made from the gel particle-containing water-based paint has gel particles 70 dispersed throughout the coating film 90, but there are also gaps 92 in some areas where only the dispersion medium 91 is present. A coating film with gaps 92 containing only the dispersion medium 91 has no hiding power, so the color of the base (the surface of the substrate 80 in Figure 11) shows through. This type of coating film results in a three-dimensional coating film, which can have a high level of designability.

[0008] On the other hand, because there are areas where the color of the base shows through, if a water-based paint containing gel-like particles for decorative grooves (hereinafter sometimes simply referred to as "paint for decorative grooves") is applied to the design area without curing it, and then another water-based paint containing gel-like particles for decorative areas (hereinafter sometimes simply referred to as "paint for design areas") is applied to the design area, there is a problem in that the color tone of the decorative groove will appear mottled in the design area.

[0009] Furthermore, the base before the application of the gel particle-containing water-based paint had to be a color close to that of the gel particle-containing water-based paint film, that is, a color that would not cause any problems in appearance even if the color of the base was visible through it. That is, when making the color tones of the design portion and the decorative groove different, the color of the base of each of the design portion and the decorative groove must also be taken into consideration.

[0010] Therefore, there was concern that using a water-based paint containing gel particles would require more labor than using enamel paint, compared to painting the entire surface of a conventional flat exterior wall with a single-color paint. In view of the above circumstances, the present invention aims to provide a building material that gives a three-dimensional, high-quality impression by imparting an appearance in which the design part and the decorative groove have clearly different color tones with a small number of steps while using an aqueous paint containing gel particles. [Means for solving the problem]

[0011] In order to solve the above problems, the present invention employs the following configuration. [1] A building material having an uneven surface consisting of a design portion and a decorative groove having a height lower than that of the design portion, A water-based paint (M) is applied to at least the decorative groove without curing the design portion, The water-based paint (M) adhering to the design portion is scraped off before the water-based paint (M) dries, After the coating film of the water-based paint (M) has dried, a water-based paint (H) is applied to the design portion while at least the bottom of the decorative groove is cured, The aqueous coating material (M) contains gel particles (X) including gel particles (X1) and optionally gel particles (X2), The aqueous coating material (H) contains gel particles (Y) including gel particles (Y1) and gel particles (Y2), The gel particles (X2) have a color difference ΔE * ab is greater than 5 and less than 20, The gel particles (X1) and the gel particles (Y1) have a color difference ΔE * ab is less than or equal to 5, The gel particles (X1) and the gel particles (Y2) have a color difference ΔE * ab is 30 or more, the proportion of the gel particles (X1) in the gel particles (X) is 1% by mass or more; the total proportion of the gel particles (X1) and the gel particles (X2) in the gel particles (X) is 70% by mass or more, the proportion of the gel particles (Y1) in the gel particles (Y) is 2 to 19% by mass, A method for producing a building material with a coating film, characterized in that the proportion of the gel particles (Y2) in the gel particles (Y) is 70 to 98 mass %. [2] The color difference ΔE between the uneven surface before application of the water-based paint (M) and the gel particles (Y2-1) having the highest mass ratio among the gel particles (Y2) is * ab The method for producing a coating-coated building material according to [1], wherein the value of the coefficient of friction coefficient is 20 or less. [3] Before applying the water-based paint (M), a step of applying an intermediate paint to the entire uneven surface to form an intermediate paint film is further included, The intermediate coating film and the gel particles (Y2-1) having the highest mass ratio among the gel particles (Y2) have a color difference ΔE * ab The method for producing a coating-coated building material according to [1] or [2], wherein the value is 20 or less. [4] The method for producing a building material with a coating film according to any one of [1] to [3], wherein the design portion comprises a large number of minute convex portions, each having an average height of 120 μm to 3 mm and an average pitch of 700 μm to 9 mm. [5] A method for producing a building material with a coating film according to any one of claims 1 to 3, wherein the height distance between the lowest point of the decorative groove and the lowest point of the design portion is 4 to 25 mm. [6] The method for producing a building material with a coating film according to any one of [1] to [4], wherein the width of the opening of the decorative groove is 5 cm or less. [7] The method for producing a coating-provided building material according to any one of [1] to [6], wherein the gel particles (X) are flake-shaped and have an average major axis of 500 μm or more and 10 mm or less. [8] The method for producing a building material with a coating film according to any one of [1] to [7], wherein the gel particles (X) are in the form of flakes and have an average thickness of 5 μm or more and 1000 μm or less. [9] The method for producing a coating-provided building material according to any one of [1] to [6], wherein the gel particles (X) are spherical and have an average major axis of 500 μm or more and 5 mm or less.

[10] A building material having an uneven surface consisting of a design portion and a decorative groove that is lower in height than the design portion; A coating film made of an aqueous paint (M) formed at least on the groove bottom of the decorative groove; A coating film made of a water-based paint (H) formed on the design portion, The coating film made of the aqueous coating material (M) contains gel particles (X) including gel particles (X1) and optionally gel particles (X2), the coating film made of the aqueous coating material (H) contains gel particles (Y) including gel particles (Y1) and gel particles (Y2), the color difference ΔE*ab between the gel particles (X2) and the gel particles (X1) is greater than 5 and not greater than 20; the color difference ΔE*ab between the gel particles (X1) and the gel particles (Y1) is 5 or less; the color difference ΔE*ab between the gel particles (X1) and the gel particles (Y2) is 30 or more; the proportion of the gel particles (X1) in the gel particles (X) is 1% by mass or more; the total proportion of the gel particles (X1) and the gel particles (X2) in the gel particles (X) is 70% by mass or more, the proportion of the gel particles (Y1) in the gel particles (Y) is 2 to 19% by mass, A building material with a coating film, characterized in that the proportion of the gel particles (Y2) in the gel particles (Y) is 70 to 98 mass %.

[11] The coating film-provided building material according to

[10] , wherein the design portion comprises a large number of minute convex portions, each having an average height of 120 μm to 3 mm and an average pitch of 700 μm to 9 mm.

[12] A building material with a coating film according to

[10] or

[11] , wherein the height distance between the lowest point of the decorative groove and the lowest point of the design portion is 4 to 25 mm.

[13] The building material with a coating film according to any one of

[10] to

[12] , wherein the width of the opening of the decorative groove is 5 cm or less. [Effects of the Invention]

[0012] According to the coating film-coated building material and the manufacturing method thereof of the present invention, it is possible to provide a building material that has a three-dimensional appearance and gives a luxurious impression by imparting an appearance with clearly different color tones to the design part and the decorative groove in a few steps while using an aqueous paint containing gel-like particles. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 10 is a diagram showing an example of the arrangement of the design portion and the decorative groove in a plan view. [Figure 2] FIG. 10 is a diagram showing another example of the arrangement of the design portion and the decorative groove in a plan view. [Figure 3] FIG. 10 is a diagram showing another example of the arrangement of the design portion and the decorative groove in a plan view. [Figure 4] FIG. 10 is a diagram showing another example of the arrangement of the design portion and the decorative groove in a plan view. [Figure 5] FIG. 10 is a diagram showing an example of a cross-sectional shape of a decorative groove. [Figure 6] FIG. 10 is a diagram showing another example of the cross-sectional shape of the decorative groove. [Figure 7] FIG. 10 is an explanatory diagram of minute convex portions of the design portion. [Figure 8] FIG. 10 is an explanatory diagram of minute convex portions of the design portion. [Figure 9] FIG. 10 is a diagram showing a schematic diagram of the state of the design part after the water-based paint (M) is scraped off when the gel particles are spherical. [Figure 10] FIG. 10 is a diagram showing a schematic diagram of the state of the design part after the water-based paint (M) is scraped off when the gel particles are in flake form. [Figure 11] FIG. 1 is an explanatory diagram of a coating film made of a water-based paint containing gel particles. DETAILED DESCRIPTION OF THE INVENTION

[0014] In this specification and claims, the use of "to" indicating a range of values ​​means that the values ​​before and after it are included as the lower and upper limits.

[0015] <Building materials> The building material of this embodiment is a building material having an uneven surface suitable for obtaining a building material with a coating film in which the design portion and the decorative groove have different color tones. The building material of this embodiment has an uneven surface on at least a portion of its surface, which is made up of a design portion and a decorative groove that is lower in height than the design portion. By applying a coating to the uneven surface of the building material of this embodiment using the manufacturing method for a building material with a coating film described below, it is possible to give the design part and the decorative groove an appearance with clearly different color tones in a few steps. Note that the dimensions and other information in the following description of building materials refer to the dimensions and other information before application of primer paint, intermediate paint, etc.

[0016] Specific examples of the shapes and arrangements of the design portion and decorative groove in plan view are shown in Figures 1 to 4. However, the uneven surface of this embodiment is not particularly limited in terms of the shapes and arrangements of the design portion and decorative groove in plan view. The building material 1 in FIG. 1 is an example in which a plurality of square design portions 11 are arranged in a checkerboard pattern, separated by decorative grooves 21 each consisting of a vertical groove 21a and a horizontal groove 21b. The building material 2 in FIG. 2 is an example in which a plurality of design portions 12, partitioned by linear decorative grooves 22, are arranged in one direction.

[0017] The building material 3 in FIG. 3 is an example in which branched design portions 13 are connected to each other, and branched decorative grooves 23 are formed between them. The building material 4 in FIG. 4 is an example in which a plurality of circular decorative grooves 24 are dispersedly arranged within the design portion 14.

[0018] There are no particular limitations on the area ratio between the design portion and the decorative groove, but the ratio of the area of ​​the design portion to the total area of ​​the design portion and the decorative groove is preferably 80 to 99%, more preferably 90 to 98%. When the area ratio of the design part is equal to or greater than the preferred lower limit, the transparency of the coating film of the decorative groove paint is less noticeable, and sufficient design properties can be expected.Furthermore, when the area ratio of the design part is equal to or less than the preferred upper limit, the height of the design part is more likely to be emphasized.

[0019] The surface of the design portion 10 is preferably a finely textured surface with a plurality of fine protrusions formed thereon, as will be described later, but is a flat surface macroscopically, as shown in Figures 5 and 6. Macroscopically, the design portion 10 has approximately the same height across the entire textured surface of the building material.

[0020] As shown in Figures 5 and 6, the decorative groove 20 is lower in height than the decorative portion 10. The heightwise distance between the decorative portion 10 and the decorative groove 20 (hereinafter sometimes referred to as the "depth of the decorative groove") is preferably 4 to 25 mm. In Figure 5, depth D1 corresponds to the heightwise distance between the decorative portion 10 and the decorative groove 20, and in Figure 6, depth D2 corresponds to the heightwise distance between the decorative portion 10 and the decorative groove 20.

[0021] By making the decorative groove depth 4mm or more, the height of the decorative groove is emphasized and the transparency of the paint film for the decorative groove is less noticeable.By making the decorative groove depth 25mm or less, painting workability is improved. The depth of the decorative groove is more preferably 8 mm to 25 mm, and even more preferably 10 mm to 25 mm.

[0022] Here, the heightwise distance between the design portion 10 and the decorative groove 20 (depth of the decorative groove) is the difference in height between the lowest points of each in a vertical cross section of the building material cut along a plane perpendicular to the surface direction of the design portion 10. The depth of a certain decorative groove is the difference in height between the lowest point of that decorative groove in its longitudinal cross section and the lowest points of the design portions on both sides of the decorative groove in its longitudinal cross section. In the present embodiment, the design portion 10 and the decorative groove 20 preferably have a depth of 4 to 25 mm when cut in any longitudinal cross section. In addition, decorative grooves also include sealing joints where a sealant is applied between boards.

[0023] There are no particular limitations on the cross-sectional shape of the decorative groove 20 in the longitudinal section. Figure 5 shows an example of a decorative groove 20 having a trapezoidal cross section in which the width W4 of the groove bottom 30 is smaller than the width W1 of the opening face of the decorative groove 20. Figure 6 shows an example of a decorative groove 20 having a rectangular cross section in which the width of the opening face of the decorative groove 20 is equal to the width of the groove bottom 30. Both Figures 5 and 6 are longitudinal cross-sectional views of the building material cut along a plane perpendicular to the surface direction of the design portion 10.

[0024] Other examples of the cross-sectional shape of the decorative groove 20 include a U-shape and an inverted triangle shape with a linear groove bottom 30. Furthermore, the widths of the opening surfaces of the plurality of decorative grooves 20 in the vertical cross section (widths W1, W2, and W3 in FIG. 5, widths W5, W6, and W7 in FIG. 6) may be the same as or different from one another.

[0025] The width of the opening surface of the decorative groove 20 in the vertical cross section is preferably 5 cm or less, more preferably 0.5 to 5 cm, and even more preferably 1 to 5 cm. There are no particular restrictions on the width of the groove bottom, as long as it is the same as or smaller than the width of the opening surface. If the width of the opening surface and groove bottom is 5 cm or less, the transparency of the decorative groove paint coating film is less noticeable. Furthermore, if it is equal to or greater than the above-mentioned preferable lower limit, it is possible to achieve a design with excellent paintability and a heavy feel.

[0026] The width of the opening surface of the decorative groove 20 refers to the length of the opening surface of the decorative groove 20 in a direction perpendicular to the longitudinal direction of the decorative groove 20 (in the case of the decorative groove 22 of the building material 2 in Figure 2, the length in the left-right direction in the figure). When the decorative grooves 20 intersect, for example when the vertical groove 21a and the horizontal groove 21b intersect as in the building material 1 in Figure 1, the intersections are not taken into consideration. When the longitudinal direction is unclear or does not exist, as in the decorative groove 23 of the building material 3 in Figure 3 and the decorative groove 24 of the building material 4 in Figure 4, the diameter of the inscribed circle inscribed in the opening surface of the decorative groove 20 is taken as the width of the opening surface of the decorative groove 20. When the width of the opening surface of the decorative groove 20 is not constant, the width of the opening surface of the decorative groove 20 means the maximum width.

[0027] Next, the fine convex portions formed on the surface of the design portion 10 will be described with reference to Fig. 7. As shown in Fig. 7, it is preferable that a large number of fine convex portions are formed on the surface of the design portion 10. The average height of the fine convex portions is preferably 120 μm or more, and more preferably 150 μm or more. The average height of the fine convex portions is preferably 3 mm or less, more preferably 2 mm or less, and even more preferably 1 mm or less.

[0028] When the average height of the fine convex portions is 3 mm or less, it is easy to uniformly trap gel particles between the fine convex portions when a water-based paint containing gel particles is applied. Also, when the average height of the fine convex portions is 120 μm or more, it is easy to keep the gel particles trapped between the fine convex portions as they are when scraped off with a spatula or the like.

[0029] The average pitch of the fine convex portions is preferably 700 μm to 9 mm, more preferably 800 μm to 7 mm, and even more preferably 1000 μm to 5 mm. When the average pitch of the fine convex portions is within the above range, after applying the water-based paint containing gel particles, the paint can be easily scraped off with a spatula or the like, and the paint remaining on the surface of the design portion 10 can be uniformly dispersed on the surface of the design portion 10 without uneven application, making it less likely that uneven scraping will occur.

[0030] The above average height and average pitch are determined by measuring the surface shape of 10 randomly selected locations from the design area (measurement distance per location: 3 cm) using a laser microscope (Keyence Corporation, VK-X3000) with a focus variation method (upper and lower lens pitch: 36 μm). The average height is determined by measuring and averaging the height of each of the multiple fine protrusions present at 10 measurement points within a measurement distance of 3 cm, and the average pitch is determined by measuring and averaging the pitch between each of the multiple fine protrusions present at 10 measurement points within a measurement distance of 3 cm.

[0031] A method for measuring the height of each minute convex portion in this measurement range will be explained using the convex portion 52 in FIG. 7 as an example. First, let h1 be the height from the lowest point between the convex portion 52 and the adjacent convex portion 51 on the left to the apex of the convex portion 52 (the distance to the apex in a direction perpendicular to the surface direction; the same applies below), and let h2 be the height from the lowest point between the convex portion 52 and the adjacent convex portion 53 on the right to the apex of the convex portion 52. The height h of the convex portion 52 is calculated using the following formula (1). h = (h1 + h2) / 2 … (1) Here, if h obtained by formula (1) is less than 80 μm, it is regarded as noise, and the height of the convex portion is not used in calculating the average height.

[0032] In addition, the pitch of each of the minute convex portions in this measurement range is, in principle, the distance between the apexes of each convex portion (the distance in the surface direction, the same applies below.) For example, in Fig. 7, the pitch between convex portion 53 and convex portion 54 is p1, the pitch between convex portion 54 and convex portion 55 is p2, and the pitch between convex portion 55 and convex portion 56 is p3. However, if the pitch is very narrow, it is not considered as an independent convex portion and is not used in calculating the average pitch.

[0033] A method for determining whether two adjacent convex portions having different heights are to be regarded as independent convex portions and a method for calculating the pitch after the determination will be described with reference to convex portion 56b in FIG. First, a horizontal line m is drawn from the apex of the lower of the two adjacent convex portions (convex portion 56b) toward the higher convex portion (convex portion 56a).

[0034] The distance p between the point where this horizontal line m intersects with the higher convex portion (convex portion 56a) and the apex of the lower convex portion (convex portion 56b) is x If the distance between the apex of the higher protrusion (protrusion 56a) and the apex of the adjacent protrusion (protrusion 57) is set to the pitch p4 between the protrusions 56 and 57.

[0035] Next, a method for determining whether two adjacent convex portions having the same height are to be regarded as independent convex portions, and a method for calculating the pitch after the determination will be described with reference to convex portions 62a, 62b, etc. in Figure 8. The distance p between the apexes of the convex portions 62a and 62b, which are equal in height, is y If the length is less than 700 μm, each protrusion is not regarded as an independent protrusion, but is regarded as one protrusion 62 as a whole.

[0036] When the entire convex portion 62 is regarded as one convex portion, the distance between adjacent convex portions is the distance between the apexes of each of the adjacent convex portions and the convex portion 62a or 62b closest to that convex portion. That is, the distance p between the apex of the left adjacent convex portion 61 and the apex of the convex portion 62a of the convex portion 62 that is closer to the convex portion 61 is 11 is the pitch between the convex portion 61 and the convex portion 62. In addition, the distance p between the apex of the convex portion 63 on the right and the apex of the convex portion 62b of the convex portion 62 that is closer to the convex portion 63 is 12 is the pitch between the protrusions 61 and 63.

[0037] There are no particular limitations on the process or method for forming the numerous fine protrusions on the design portion 10, but they can be formed, for example, by cutting or by using a mold with fine protrusions and recesses. There are also no particular limitations on the timing at which the fine protrusions are formed, but for example, when the building material is ALC, they can be formed before or after the hardening of the material that forms the ALC, or before or after autoclave treatment. The average height and average pitch of the fine convex portions can be adjusted during the formation process, or by adjusting the cutting processing conditions or the average height and average pitch of the fine irregularities formed in the mold.

[0038] The building material is typically a wall material. Examples of building materials include mortar, ceramic siding, extruded cement board, lightweight aerated concrete (ALC), and laminates in which mortar is laminated on the surface of a substrate (such as ceramic siding). These building materials can be used, and it is preferable that the design portion has a large number of fine convex portions.

[0039] <Paint> [Gel-like particles] The water-based paint (M) and the water-based paint (H) used in the method for producing a building material with a coating film of this embodiment both contain gel particles. The gel particles have droplets in which at least a color pigment is dispersed and a gelling film covering the surface of the droplets. The gelling film is a three-dimensional network structure. In addition to the color pigment dispersed in the droplets, the droplets may contain various raw material components, such as unreacted colloid-forming substances and gelling agents, which will be described later in the method for producing a gelling particle dispersion.

[0040] The gel particles in the aqueous coating material may have a variety of shapes, such as flakes (which can also be referred to as scales, flats, plates, or thin flakes), spheres, cubes, lines, etc. Among these, flakes or spheres are preferred, with flakes being particularly preferred, from the viewpoints of productivity, coating workability, and achieving good design properties.

[0041] In the present invention, the term "flake-like" refers to a shape having opposing first and second surfaces and an aspect ratio of 2 or more. The aspect ratio can be calculated by dividing the major axis by the thickness. In the case of a flake-like shape, the major axis refers to the longer of the distance between the two most distant points on the periphery of the first surface and the distance between the two most distant points on the periphery of the second surface. In the case of a flake-like shape, the thickness refers to the distance between the most distant parts of the first surface and the second surface. There are no particular limitations on the shape of the opposing first and second surfaces, and various shapes such as a circle, an ellipse, a triangle, a rectangle, etc. are usable. Usually, they are circle or ellipse.

[0042] When the gel particles contained in the aqueous coating material are in the form of flakes, the average major axis is preferably 500 μm or more, more preferably 1,000 μm or more, and is preferably 10 mm or less, more preferably 8 mm or less. If the average major axis of the gel particles is within the above range, when the gel particles adhering to the design portion are scraped off with a spatula or the like, some of the gel particles adhering to the uneven surface of the design portion tend to remain uniformly.

[0043] When the gel particles contained in the aqueous coating material are in the form of flakes, the average thickness is preferably 5 μm or more, more preferably 50 μm or more, and most preferably 100 μm or more, and is preferably 1000 μm or less, more preferably 500 μm or less, and most preferably 300 μm or less. When the average thickness is equal to or greater than the preferred lower limit, the color of the gel particles is easily reflected in the coating film. When the average thickness is equal to or less than the preferred upper limit, the average aspect ratio is easily equal to or less than the preferred upper limit.

[0044] When the gel particles contained in the aqueous coating material are in the form of flakes, the average aspect ratio (average major axis length / average thickness) is 2 or more, preferably 2-500, and more preferably 5-200. When the average aspect ratio is equal to or less than the preferred upper limit, the gel particles are easily oriented in the resulting coating film, and the color of the gel particles is easily reflected in the coating film.When the average aspect ratio is equal to or more than the preferred lower limit, the adhesion of the gel particles to the substrate is improved, and the color of the gel particles is easily reflected in a wide range of coating films.

[0045] In the present invention, the term "spherical" refers to a three-dimensional shape that does not have faces that can be clearly distinguished by line segments, such as a cube or a triangular pyramid, and has an aspect ratio of less than 2. The aspect ratio can be calculated by dividing the major axis by the minor axis. In the case of a spherical particle, the major axis refers to the distance between the most distant points on the outer surface of a gel-like particle (not the distance along the periphery, but the linear distance between the two opposing points), and the minor axis refers to the distance between the closest points on the outer surface of a particle (not the distance along the periphery, but the linear distance between the two opposing points), which corresponds to the thickness in the case of a flake particle.

[0046] When the gel particles in the aqueous coating material are spherical, the average major axis is preferably 500 μm or more, more preferably 1 mm or more, and is preferably 5 mm or less, more preferably 4 mm or less. If the average major axis of the gel particles is within the above range, when the gel particles adhering to the design portion are scraped off with a spatula or the like, some of the gel particles adhering to the uneven surface of the design portion tend to remain uniformly.

[0047] The average major axis length and average thickness when the gel particles are flake-shaped, and the average major axis length and average minor axis length when the gel particles are spherical, are each determined by randomly selecting 20 gel particles from the water-based paint and measuring them with a ruler or microscope, and then calculating the arithmetic mean of the measured values.

[0048] [Method of manufacturing gel particle dispersion] A gel particle dispersion containing gel particles can be produced by reacting an emulsion solution in which a colloid-forming substance is dispersed in a dispersion medium with a gelling agent solution containing at least a gelling agent in the presence of at least a coloring pigment. The emulsion solution preferably contains a resin. The coloring pigment is preferably contained in the emulsion solution.

[0049] Examples of color pigments include inorganic pigments such as carbon black, titanium oxide, iron oxide, lead chromate, cadmium yellow, and cadmium red; organic pigments such as phthalocyanine blue, phthalocyanine green, and quinacridone red; and colored resin chips. These may be used alone or in combination of two or more.

[0050] The average particle diameter of the color pigment is preferably 10 to 1,000 nm, and more preferably 10 to 800 nm. When the average particle diameter of the color pigment is equal to or greater than the lower limit, the color of the color pigment can be easily reflected in the color of the gel particles. When the average particle diameter of the color pigment is equal to or less than the upper limit, the color pigment can be easily dispersed stably in the dispersion medium. The average particle diameter of the color pigment is the median diameter (50% cumulative particle diameter) calculated from the volume average diameter measured by laser diffraction / scattering.

[0051] The proportion of the color pigment in the gel particles is preferably 1 to 70% by mass, more preferably 2 to 60% by mass, and particularly preferably 3 to 55% by mass. When the proportion of the color pigment is equal to or greater than the lower limit of the preferred range, excellent hiding power is achieved. When the proportion is equal to or less than the upper limit of the preferred range, excellent coating film performance such as water resistance is achieved.

[0052] The colloid-forming substance may be any substance capable of reacting with a gelling agent to form a gelled film. Examples of colloid-forming substances include cellulose derivatives, polyethylene oxide, polyvinyl alcohol, and natural polymers such as casein, starch, galactomannan, guar gum, and locust bean gum. These colloid-forming substances may be used alone or in combination of two or more. The content of the colloid-forming substance (dry solid content) is preferably 0.1 to 20% by mass, more preferably 0.5 to 15% by mass, based on the total amount of the emulsion solution.

[0053] As described above, the gelling agent reacts with the colloid-forming substance to form crosslinks, thereby forming a gelled film containing a three-dimensional network structure. Examples of gelling agents include montmorillonite, bentonite, tannic acid, borates, aluminum salts, barium salts, calcium salts, magnesium salts, etc. These gelling agents may be used alone or in combination of two or more. The content of the gelling agent (dry solid content) is preferably 0.1 to 20% by mass, and more preferably 0.5 to 15% by mass, based on the total mass of the gelling agent solution.

[0054] The ratio of the gelling agent (dry solid content) to the colloid-forming substance (dry solid content) is preferably in the range of 3:1 to 1:3, and more preferably in the range of 2:1 to 1:2. By setting the amount of gelling agent (dry solid content) used relative to the colloid-forming substance (dry solid content) within the above range, a gelled film can be obtained stably.

[0055] The resin is an aqueous resin that can be dissolved or dispersed in an aqueous medium, and the aqueous resin is preferably a resin that can be dispersed in an aqueous medium (water-dispersible resin). By including a resin in the emulsion solution, it is possible to obtain gel particles that are less likely to lose their shape during coating.

[0056] There are no particular restrictions on the type of aqueous resin, and it can be selected appropriately depending on the performance required for the coating film. Examples of types of resin include acrylic resin, urethane resin, vinyl acetate resin, silicone resin, fluororesin, acrylic urethane resin, acrylic silicone resin, acrylic fluororesin, acrylic styrene resin, acrylonitrile resin, vinyl chloride resin, epoxy resin, Veova (branched fatty acid vinyl ester), natural rubber, synthetic rubber, and copolymers thereof.

[0057] These aqueous resins may be used alone or in combination of two or more. Among them, synthetic resins such as acrylic resins, acrylic silicone resins, and acrylic fluororesins are preferred because of their excellent weather resistance and water resistance. The content of the resin is preferably 5 to 70% by mass, and more preferably 10 to 50% by mass, based on the total amount of the emulsion solution.

[0058] An extender pigment may be used as a raw material for obtaining a gel particle dispersion. Extender pigment is a general term for achromatic pigments used in paints. Examples of extender pigments include kaolin, barium sulfate, hydrous magnesium silicate, and calcium carbonate. The extender pigment may be used alone or in combination of two or more. The extender pigment may be blended into either the emulsion solution or the gelling agent solution.

[0059] As raw materials for obtaining the gel particle dispersion, decorative materials and additives other than color pigments may be used. Examples of the decorative material include glitter pigments, aggregates, matte beads, etc. Examples of the glitter pigment include pearl pigments, mica pigments, mica-coated pearl pigments, aluminum powder, stainless steel powder, etc.

[0060] Examples of additives include emulsifiers, pH adjusters, antifoaming agents, viscosity adjusters, film-forming aids, antifreeze agents, dispersants, wetting agents, penetration aids, preservatives, surface conditioners, ultraviolet absorbers, antioxidants, and heat-shielding agents. Decorative materials and additives other than color pigments may be blended into either the emulsion solution or the gelling agent solution.

[0061] The dispersion medium of the emulsion solution is water alone or an aqueous medium in which a water-compatible solvent is added to water. The proportion of water in the aqueous medium is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more. The water that can be used may be ion-exchanged water, tap water, etc. Examples of solvents that are compatible with water include alcohols such as ethanol and isopropyl alcohol, and ethylene glycol. As the solvent for the gelling agent solution, the same solvent as the dispersion medium for the emulsion solution can be used.

[0062] [Color of gel particles] The gel particles contained in the water-based paint (M) and the water-based paint (H) used in the method for producing a building material with a coating film of this embodiment have a specific relationship in terms of color difference. Color difference ΔE between two types of gel particles * ab is a value obtained by measuring the color of a coating film formed from each gel particle taken out of the gel particle dispersion according to JIS Z 8741-4:2013 and calculating it using the following formula (2).

[0063]

number

[0064] In equation (2), ΔL * is the lightness index L of each coating made with two types of gel particles. * difference, Δa * is the L of each coating film made with two types of gel particles. * a * b* a in space * Coordinate difference, Δb * is the L of each coating film made with two types of gel particles. * a * b * b in space * The difference in coordinates. The specific method for extracting the gel particle dispersion and forming a coating film will be described in detail in the examples below.

[0065] [Water-based paint (M)] The water-based paint (M) is a paint mainly used to impart a desired color tone to the decorative groove, and contains gel particles (X). The water-based coating material (M) preferably contains a binder resin in addition to the gel particles (X), and may also contain various additives.

[0066] The gel particles (X) contain gel particles (X1) and, optionally, gel particles (X2). Furthermore, the gel particles (X) may contain gel particles (X3) other than the gel particles (X1) and the gel particles (X2) as long as the effects of the present invention are not impaired.

[0067] The gel particles (X1) are the standard gel particles among the gel particles used in the present invention. The gel particles (X1) are homogeneous gel particles, or the color difference ΔE * ab Gel particles of similar color with a value of 5 or less are used. Homogeneous gel particles refer to gel particles produced in a single lot.

[0068] Gel particles of similar colors with a mutual color difference ΔE*ab of 5 or less are gel particles manufactured in multiple lots, and the color difference ΔE * ab These are gel particles with a molecular weight of 5 or less. That is, when gel particles (X1) manufactured in multiple production lots are used, the color difference ΔE between gel particles manufactured in one production lot and gel particles manufactured in another production lot (including those with different compositions) is * abIt is necessary to make the color similar to the one shown in the image below 5.

[0069] In addition, when the gel particles (X1) contain gel particles manufactured in multiple production lots, the colorimetric data of the entire gel particles (X1) is a value obtained by weighting the colorimetric data of each production lot by mass (solid content) ratio. Therefore, the color difference ΔE between the gel particles (X1) and other gel particles other than the gel particles (X1) in this case is * ab is the color difference between the color measurement data of other gel particles and the weighted average value of the color measurement data of gel particles (X1) manufactured in multiple production lots.

[0070] The color difference ΔE between gel particles (X2) and gel particles (X1) is * ab The color difference ΔE between the gel particles (X2) and the gel particles (X1) is 20 or less, but does not fall under the category of the gel particles (X1). * ab is greater than 5. As long as this condition is satisfied, the gel particles (X2) may contain two or more types of gel particles having different colors or the same color.

[0071] Color difference ΔE between gel particles (X1) and gel particles (X2) * ab is preferably 18 or less, and more preferably 16 or less. The color difference ΔE between gel particles (X1) and gel particles (X2) is * ab By making the value of the color difference between the coating film of the water-based paint (M) and the coating film of the water-based paint (H) described below easily occurs when the color difference is 20 or less. By including gel particles (X2) that are not similar in color to the gel particles (X1), a three-dimensional appearance can be achieved.

[0072] The proportion of the gel particles (X1) in the gel particles (X) is 1% by mass or more, preferably 15% by mass or more, and more preferably 30% by mass or more. The proportion of the gel particles (X1) in the gel particles (X) is preferably 95% by mass or less, more preferably 90% by mass or less, and particularly preferably 85% by mass or less.

[0073] When the proportion of the gel particles (X1) is 1% by mass or more, the gel particles (X1) of approximately the same color as the gel particles (Y1) in the water-based paint (H) described below can be uniformly left in the design area after scraping with a spatula, etc., thereby preventing uneven appearance. When the proportion of the gel particles (X1) is 95% by mass or less, a three-dimensional appearance is obtained, improving the design.

[0074] The total proportion of the gel particles (X1) and the gel particles (X2) in the gel particles (X) is 70% by mass or more, preferably 75 to 95% by mass, and more preferably 80 to 90% by mass. When the total proportion of the gel particles (X1) and the gel particles (X2) is 70% by mass or more, it is easy to create a difference in color tone between the coating film made of the water-based paint (M) and the coating film made of the water-based paint (H) described below. When the total proportion is equal to or less than the preferred upper limit, a three-dimensional appearance can be achieved.

[0075] The proportion of the gel particles (X) in the water-based coating material (M) (excluding the dispersion medium outside the gel particles (X)) is preferably 5 to 70 mass %, more preferably 7 to 55 mass %. When the proportion of the gel particles (X) is at least the lower limit of the preferred range, the coating film performance such as weather resistance is excellent. When the proportion is at most the upper limit of the preferred range, the coating workability is good.

[0076] The binder resin may be only a resin derived from the gel particle (X) dispersion, only a resin blended separately from the gel particle (X) dispersion, or both a resin derived from the gel particle (X) dispersion and a resin blended separately from the gel particle (X) dispersion. In order to obtain excellent elasticity of the coating film, it is preferable to use both a resin derived from the gel particle (X) dispersion and a resin blended separately from the gel particle (X) dispersion.

[0077] The binder resin to be blended separately from the gel particle (X) dispersion can be an aqueous resin similar to the resins listed as raw materials for the gel particle dispersion. The binder resin to be blended separately preferably has the same dispersion form and type as the resin used as the raw material for the gel particle (X) dispersion, since this provides excellent elasticity to the coating film. For example, the binder resin to be blended separately and the raw material resin for the gel particle (X) dispersion can both be an acrylic silicone resin dispersible in an aqueous medium. An example in which the binder resin and the raw material resin of the gel particle (X) dispersion are different in type is where the binder resin is an acrylic silicone resin and the raw material resin of the gel particle (X) dispersion is an acrylic resin.

[0078] The proportion of the binder resin in the aqueous coating material (M) (including the resin inside the gel particles (X)) is preferably 7 to 70 mass %, more preferably 10 to 70 mass %. When the proportion of the binder resin is at least the lower limit of the preferred range, the coating film performance such as weather resistance is excellent, and when the proportion is at most the upper limit of the preferred range, the coating workability is good.

[0079] The additive may be only an additive derived from the gel particle (X) dispersion, only an additive blended separately from the gel particle (X) dispersion, or both an additive derived from the gel particle (X) dispersion and an additive blended separately from the gel particle dispersion. As additives contained in the water-based coating material (M), additives similar to those of the resins listed as raw materials for the gel particle dispersion can be used. The water-based paint (M) may contain unreacted colloid-forming substances and gelling agents (raw materials for gel particle dispersions).

[0080] The dispersion medium of the water-based coating material (M) preferably contains a dispersion medium derived from the gel particle (X) dispersion, as well as a dispersion medium formulated separately from the gel particle (X) dispersion. As a dispersion medium to be added separately from the dispersion medium derived from the gel particle (X) dispersion, the same aqueous medium as the dispersion medium exemplified as the raw material for the gel particle dispersion can be used.

[0081] The dry solid content of the aqueous coating material (M) is preferably 15 to 80 mass %, more preferably 25 to 70 mass %. When the dry solids concentration of the water-based paint (M) is at least the preferred lower limit, the coating film performance such as weather resistance is excellent. When it is at most the preferred upper limit, the coating workability is good.

[0082] The viscosity of the water-based paint (M) at 23° C. as measured with a Brookfield viscometer (TVB-10, manufactured by Toki Sangyo Co., Ltd.) is preferably 10 to 200 Pa·s, and more preferably 30 to 150 Pa·s. When the viscosity of the water-based paint (M) is equal to or higher than the preferred lower limit, sagging is less likely to occur during application. When the viscosity is equal to or lower than the preferred upper limit, the paint is easily scraped off, resulting in a good finished appearance.

[0083] [Water-based paint (H)] The water-based paint (H) is a paint mainly used to impart a desired color tone to the design portion, and contains gel particles (Y). The water-based coating material (H) preferably contains a binder resin in addition to the gel particles (Y), and may also contain various additives.

[0084] The gel particles (Y) include gel particles (Y1) and gel particles (Y2). Furthermore, they may also include gel particles (Y3) other than gel particles (Y1) and gel particles (Y2) within the scope of not impairing the effects of the present invention. The gel particles (Y1) and gel particles (Y2) may each include two or more types of gel particles of the same or different colors, as long as they each satisfy the following conditions:

[0085] The color difference ΔE between gel particles (X1) and gel particles (Y1) * ab is 5 or less, and the color difference ΔE * ab The color difference ΔE between the gel particles (Y1) and the gel particles (X1) may be zero. * abis preferably 3 or less, and is particularly preferably the same gel particles as the gel particles (X1). Color difference ΔE between gel particles (X1) and gel particles (Y1) * ab Since the value is 5 or less and the color is similar, even if the gel particles (X1) remaining in the design area after scraping it off with a spatula or the like can be seen through the coating film of the water-based paint (H), it does not give the impression of uneven appearance.

[0086] The color difference ΔE between gel particles (X1) and gel particles (Y2) * ab The color difference ΔE between the gel particles (X1) and the gel particles (Y2) is 30 or more. * ab is more preferably 40 or more, even more preferably 50 or more, and most preferably 60 or more. Color difference ΔE between gel particles (X1) and gel particles (Y2) * ab By having a value of 30 or more, it becomes easier to create a difference in color tone between the coating film made with water-based paint (H) and the coating film made with water-based paint (M), and the contrast between the design part and the decorative groove becomes stronger.

[0087] The proportion of the gel particles (Y1) in the gel particles (Y) is 2 to 19% by mass, preferably 3 to 15% by mass, and more preferably 4 to 13% by mass. By setting the proportion of the gel particles (Y1) to 2% by mass or more, even if the gel particles (X1) remaining in the design part after being scraped off with a spatula or the like can be seen through the coating film of the water-based paint (H), it is possible to prevent the appearance from being perceived as uneven. By setting the proportion of the gel particles (Y1) to 19% by mass or less, it becomes easier to create a difference in color tone between the coating film made of the water-based paint (H) and the coating film made of the water-based paint (M), and the contrast between the design part and the decorative groove becomes stronger.

[0088] The proportion of the gel particles (Y2) in the gel particles (Y) is 70 to 98 mass %, preferably 70 to 97 mass %, and more preferably 70 to 96 mass %. When the proportion of the gel particles (Y2) is 70% by mass or more, it is easy to produce a difference in color tone between the coating film made of the water-based paint (H) and the coating film made of the water-based paint (M).When the proportion of the gel particles (Y2) is 98% by mass or less, uneven appearance is less likely to occur.

[0089] The proportion of the gel particles (Y) in the water-based coating material (H) (excluding the dispersion medium outside the gel particles (Y)) is preferably 5 to 70 mass %, more preferably 7 to 55 mass %. When the proportion of the gel particles (Y) is at least the lower limit of the preferred range, the coating film performance such as weather resistance is excellent, and when it is at most the upper limit of the preferred range, the coating workability is good.

[0090] The binder resin may be only a resin derived from the gel particle (Y) dispersion, only a resin blended separately from the gel particle (Y) dispersion, or both a resin derived from the gel particle (Y) dispersion and a resin blended separately from the gel particle (Y) dispersion. In order to obtain excellent elasticity of the coating film, it is preferable to use both a resin derived from the gel particle (Y) dispersion and a resin blended separately from the gel particle (Y) dispersion.

[0091] As the binder resin to be blended separately from the gel-like particle (Y) dispersion, similar to the binder resin to be blended separately from the gel-like particle (X) dispersion in the aqueous coating material (M), the same aqueous resins as those listed as raw materials for the gel-like particle dispersion can be used, and it is preferable that the dispersion form and type of the binder resin be the same as those of the resin used as the raw material for the gel-like particle dispersion (Y).

[0092] The preferred range of the proportion of binder resin in the aqueous paint (H) (including the resin inside the gel-like particles (Y)) is the same as the preferred range of the proportion of binder resin in the aqueous paint (M) (including the resin inside the gel-like particles (X)).

[0093] The additive may be only an additive derived from the gel particle (Y) dispersion, only an additive blended separately from the gel particle (Y) dispersion, or both an additive derived from the gel particle (Y) dispersion and an additive blended separately from the gel particle dispersion. As the additives contained in the water-based coating material (H), the same additives as those of the resins listed as raw materials for the gel particle dispersion can be used. The aqueous coating material (H) may contain unreacted colloid-forming substances and gelling agents (raw materials for gel particle dispersions).

[0094] The dispersion medium of the water-based coating material (H) preferably contains a dispersion medium derived from the gel particle (Y) dispersion, as well as a dispersion medium that is blended separately from the gel particle (Y) dispersion. As a dispersion medium to be added separately from the dispersion medium derived from the gel particle (Y) dispersion, the same aqueous medium as the dispersion medium exemplified as the raw material for the gel particle dispersion can be used. The preferred ranges of the dry solids concentration of the water-based paint (H) and the viscosity of the water-based paint (H) at 23°C measured with a B-type viscometer (TVB-10, manufactured by Toki Sangyo Co., Ltd.) are the same as those of the water-based paint (M).

[0095] [Intermediate paint] In the method for producing a building material with a coating film of this embodiment, an intermediate coating may be used in addition to the water-based coating material (M) and the water-based coating material (H). The intermediate coating material is a coating material for forming an intermediate coating film on the building material before the water-based coating material (M) and the water-based coating material (H) are applied.

[0096] It is preferable that the intermediate coating film formed by applying the intermediate coating is a paint of the same color tone as the coating film obtained by applying the water-based coating (H). This makes it less likely that uneven appearance will occur, where the intermediate coating film is conspicuous due to the water-based coating (H) showing through, and also emphasizes the color tone of the design part made of the water-based coating (H), improving the design. Specifically, when a coating film obtained by applying the water-based paint (H) to a 30 cm square plate and an intermediate coating film are placed side by side and observed from a distance of 5 to 10 m, it is preferable that there is no significant difference in the color of the two coating films.

[0097] In order to make the intermediate coating film and the coating film obtained by applying the water-based paint (H) have the same color tone, the color difference ΔE between the intermediate coating film and the gel-like particles (Y2-1) having the highest mass ratio among the gel-like particles (Y2) in the water-based paint (H) is * ab It is preferable to set the value to 20 or less. Here, the gel particles (Y2-1) are homogeneous gel particles, but the color difference ΔE * ab The gel particles may be of similar colors with a color difference ΔE of 5 or less. * ab The gel particles of similar colors having a value of 5 or less are similar to those described for the gel particles (X1). Color difference ΔE between intermediate coating film and gel particles (Y2-1) * ab is more preferably 18 or less, and even more preferably 16 or less.

[0098] The primer paint contains a resin and, if necessary, other components in an aqueous medium. The aqueous medium may be the same as the dispersion medium listed as a raw material for the gel particle dispersion. The resin may be the same as the aqueous resin listed as a raw material for the gel particle dispersion. Other components include the design materials and additives listed as raw materials for the gel particle dispersion.

[0099] [Undercoat paint] In the method for producing a building material with a coating film of this embodiment, a primer paint may also be used. The use of a primer paint can improve the adhesion between the substrate and the coating film. As the primer paint, any sealer can be used, such as a water-based sealer, an organic solvent-based sealer, a solventless sealer, etc. As the resin contained in the primer paint, the same resins as those listed as raw materials for the gel particle dispersion can be used. The undercoat paint may contain other components, such as the additives listed as ingredients of the gel particle dispersion.

[0100] <Method of manufacturing coated building materials> The manufacturing method of the coating-coated building material of this embodiment is a method in which, on the uneven surface of a building material having a design portion and a decorative groove that is lower in height than the design portion, a water-based paint (M) is applied to the decorative groove without curing the design portion, the water-based paint (M) adhering to the design portion is scraped off with a spatula or the like before the water-based paint (M) dries, and after the coating of the water-based paint (M) has dried, a water-based paint (H) is applied to the design portion while curing at least the bottom of the decorative groove. In this specification and claims, "curing" means covering a specific location to prevent paint from adhering to that location.

[0101] In the method for producing a building material with a coating film of this embodiment, it is preferable to apply an intermediate coating to the entire uneven surface to form an intermediate coating film before applying the water-based coating material (M). Furthermore, before applying the intermediate coating material or the water-based coating material (M), a primer coating may be applied to form an intermediate coating film, if necessary.

[0102] [Painting of primer paint] There are no limitations on the application method for the primer paint as long as it can be applied to the entire uneven surface of the coating film-covered building material, and examples include known application methods such as brush coating, trowel coating, roller coating, spray coating, roll coating, flow coating, etc. Applying the primer paint to form an primer coating film on the uneven surface can improve the adhesion between the substrate and the coating film.

[0103] The temperature of the primer paint during application is preferably 5 to 40°C, more preferably 10 to 30°C. Drying after coating may be carried out at room temperature or by heating, as long as the aqueous medium can be removed. The drying temperature is, for example, 5 to 90° C. The drying time varies depending on the drying temperature, but is, for example, 5 minutes to 48 hours.

[0104] The amount of primer paint to be applied before drying can be selected appropriately depending on the average thickness of the coating film to be formed, but is preferably 100 to 1000 g / m 2 is preferable, and 150 to 800 g / m 2When the coating amount before drying is within the above range, the adhesion between the substrate and the coating film becomes good. The dry coating amount of primer is 10 to 800 g / m 2 is preferred, and 20 to 700 g / m 2 When the dry coating amount is within the above range, the adhesion between the substrate and the coating film becomes good.

[0105] [Painting of primer paint] There are no limitations on the application method for the intermediate coating paint as long as it can be applied to the entire uneven surface of the coating film-covered building material, and examples include known application methods such as brush coating, trowel coating, roller coating, spray coating, roll coating, flow coating, etc. Applying the intermediate coating paint to form an intermediate coating film on the uneven surface can improve the water resistance and durability of the building material.

[0106] The temperature of the intermediate coating material during application is preferably 5 to 40°C, more preferably 10 to 30°C. Drying after coating may be carried out at room temperature or by heating, as long as the aqueous medium can be removed. The drying temperature is, for example, 5 to 90° C. The drying time varies depending on the drying temperature, but is, for example, 5 minutes to 48 hours.

[0107] The amount of primer paint to be applied before drying can be selected appropriately depending on the average thickness of the coating film to be formed, but is preferably 100 to 1000 g / m 2 is preferable, and 150 to 800 g / m 2 When the coating amount before drying is equal to or greater than the lower limit of the preferred range, the coating film performance such as water resistance is excellent. When the coating amount is equal to or less than the upper limit of the preferred range, problems such as coating film cracking during drying are less likely to occur.

[0108] The dry coating amount of the primer paint is 30 to 800 g / m 2 is preferred, and 50 to 700 g / m 2 When the dry coating amount is equal to or greater than the lower limit of the preferred range, the coating film performance such as water resistance is excellent. When the dry coating amount is equal to or less than the upper limit of the preferred range, problems such as coating film cracking are less likely to occur when the coating film is dried.

[0109] [Color tone of uneven surface before painting with water-based paint (M)] The color tone of the uneven surface before painting with the water-based paint (M) is the color difference ΔE * ab is preferably 20 or less, more preferably 18 or less, and even more preferably 16 or less. This makes it less likely that uneven appearance will occur, in which the water-based paint (H) coating film shows through and the intermediate coating film is clearly visible. In addition, if an intermediate coating is applied, the color tone of the intermediate coating film corresponds to the color tone of the uneven surface of the building material itself, if an intermediate coating is not applied, or the color tone of the uneven surface of the building material itself that can be seen through the primer coating film.

[0110] [Water-based paint (M)] The water-based paint (M) is applied to at least the decorative groove of the coating-coated building material. At this time, the design part is not cured. In other words, the water-based paint (M) may be applied not only to the decorative groove but also to the design part.

[0111] The water-based paint (M) may be applied so that it overflows only onto the design portion near the decorative groove, or may be applied to the entire design portion. In other words, the water-based paint (M) may be applied to the entire uneven surface of the coating-film-attached building material. Applying paint only to the design area near the decorative groove reduces the amount of water-based paint (M) used. It also shortens the time required for the subsequent scraping process. On the other hand, applying paint to the entire uneven surface of the coated building material, including the entire design area, increases the uniformity of the design area and further reduces unevenness.

[0112] There are no limitations on the application method of the water-based paint (M) as long as it can be applied at least to the decorative groove, and examples thereof include known application methods such as brush application, trowel application, roller application, spray application, roll application, and flow application. Among these, spray painting is preferred in terms of obtaining a good appearance.

[0113] The temperature of the water-based coating material (M) during application is preferably 5 to 40°C, more preferably 10 to 30°C. Drying after coating may be carried out at room temperature or by heating, as long as the aqueous medium can be removed. The drying temperature is, for example, 5 to 90° C. The drying time varies depending on the drying temperature, but is, for example, 5 minutes to 48 hours.

[0114] The amount of water-based paint (M) to be applied before drying can be selected appropriately depending on the average thickness of the coating film to be formed, but is preferably 250 to 800 g / m 2 is preferable, and 300 to 600 g / m 2 When the coating amount before drying is equal to or greater than the lower limit of the preferred range, excellent hiding power and coating film performance such as weather resistance are achieved. When the coating amount is equal to or less than the upper limit of the preferred range, problems such as sagging during coating are less likely to occur.

[0115] The dry coating amount of water-based paint (M) is 30 to 640 g / m 2 is preferable, and 90 to 420 g / m 2 When the dry coating amount is equal to or greater than the lower limit of the preferred range, the coating film performance such as weather resistance is excellent. When the dry coating amount is equal to or less than the upper limit of the preferred range, problems such as sagging during coating are less likely to occur.

[0116] [Scraping off water-based paint (M)] The water-based paint (M) is applied to the decorative groove without curing the design part, so the water-based paint (M) adheres to part or all of the design part. In the method of this embodiment, the water-based paint (M) adhering to the design portion is scraped off with a spatula or the like along the surface direction of the design portion 10 before it dries.

[0117] The spatula is not particularly limited as long as it can scrape off the paint (M) along the surface direction of the design portion 10, but it is preferable that the part that comes into contact with the substrate or the intermediate coating film formed on the substrate when scraping off is made of a soft material such as rubber or plastic. If the above conditions are met, the paint (M) can be scraped off without damaging the intermediate coating film or the substrate. Specific examples include rubber spatulas and silicone spatulas.

[0118] [Water-based paint (H)] After the water-based paint (M) adhering to the design portion is scraped off with a spatula or the like, the water-based paint (H) is applied to the design portion while at least the bottom of the decorative groove is cured. The curing is a process carried out to prevent the water-based paint (H) for the design portion from adhering to at least the bottom of the decorative groove when the water-based paint (H) for the design portion is applied.

[0119] Materials used for curing include joint rods, masking tape, etc. The material of the masking tape is not particularly limited. The portion to be cured is at least the bottom of the decorative groove, but may also extend to the inner surface of the decorative groove.

[0120] There are no limitations on the coating method for the water-based coating material (H) as long as it can be applied to the entire design portion, and examples thereof include known coating methods such as brush coating, trowel coating, roller coating, spray coating, roll coating, and flow coating. Among these, spray painting is preferred in terms of obtaining a good appearance.

[0121] The temperature of the water-based coating material (H) during application is preferably 5 to 40°C, more preferably 10 to 30°C. Drying after coating may be carried out at room temperature or by heating, as long as the aqueous medium can be removed. The drying temperature is, for example, 5 to 90° C. The drying time varies depending on the drying temperature, but is, for example, 5 minutes to 48 hours.

[0122] The amount of water-based paint (H) to be applied before drying can be appropriately selected depending on the average thickness of the coating film to be formed, but is preferably 250 to 800 g / m 2 is preferable, and 300 to 600 g / m 2 When the coating amount before drying is equal to or greater than the lower limit of the preferred range, the coating film performance such as weather resistance is excellent. When the coating amount is equal to or less than the upper limit of the preferred range, problems such as sagging during coating are less likely to occur.

[0123] The dry coating amount of water-based paint (H) is 30 to 640 g / m2 is preferable, and 90 to 420 g / m 2 When the dry coating amount is equal to or greater than the lower limit of the preferred range, the coating film performance such as weather resistance is excellent. When the dry coating amount is equal to or less than the upper limit of the preferred range, problems such as sagging during coating are less likely to occur.

[0124] <Coated building materials> The coating-coated building material of this embodiment comprises a building material having an uneven surface consisting of a design portion and a decorative groove that is lower in height than the design portion, a coating film made of a water-based paint (M) formed at least on the bottom of the decorative groove, and a coating film made of a water-based paint (H) formed on the design portion, and it is preferable that the design portion has a large number of fine convex portions. Preferred embodiments of the water-based paint (M), the water-based paint (H), and the building material are as explained above.

[0125] <Action and effect> The inventors first investigated the decorative groove. Specifically, a white enamel paint of the same color as the design portion was applied to the entire uneven surface and dried. After the design portion was cured, a black-colored water-based paint containing gel particles for the decorative groove was applied to the decorative groove. After the paint for the decorative groove dried, a white-colored water-based paint containing gel particles for the design portion was applied to the design portion while the decorative groove was cured. After drying, the appearance was observed.

[0126] As a result, it was found that as long as the width of the decorative groove is not too wide, even if the coating film made of the gel-like particle-containing water-based paint for the decorative groove does not have hiding power, the transparency of the coating film made of the paint for the decorative groove is hardly noticeable. In other words, since the transparency of the decorative groove is not noticeable regardless of the color of the base, it is acceptable to use a color tone for the base of the decorative groove that matches the color tone of the design part, so it was found that the effort of using different color tones for the base of the decorative groove and the design part can be eliminated.

[0127] Furthermore, in order to reduce the effort required to apply different gel particle-containing water-based paints to the design area and the decorative groove, the inventors investigated a method in which a gel particle-containing water-based paint for the decorative groove is applied to the entire uneven surface of the building material without curing the design area, and then removed from the design area before it dries. Specifically, an enamel paint of the same color tone as the design part was applied to the entire uneven surface and allowed to dry, and then paint for the decorative groove was applied to the entire surface of the object to be coated without curing the decorative groove and the design part.

[0128] Thereafter, before the paint for the decorative groove dried, the paint for the decorative groove adhering to the design portion was scraped off with a spatula, etc. After the paint for the decorative groove dried, the decorative groove was cured, and then a paint for the design portion having a different color tone from the paint for the decorative groove was applied to the design portion and dried. As a result, although this method makes it possible to form gel particle-containing water-based paint coatings with different color tones in the decorative groove and design area with fewer steps than conventional methods, various problems have arisen.

[0129] In other words, the inventors tried this method on various exterior wall materials, but found that it was difficult to completely scrape off the paint for the decorative groove that had adhered to the design part, and in areas where it was not scraped off sufficiently, the paint film for the decorative groove would show through underneath the paint film for the design part, resulting in an uneven appearance.

[0130] Furthermore, in areas of the design portion where the paint for the decorative grooves has not been scraped off sufficiently, a coating film of a certain thickness of the paint for the decorative grooves is formed. Therefore, when a coating film of the paint for the design portion is formed on top of that, there is a problem that unevenness in appearance occurs due to the appearance of unevenness compared to other areas, or the gloss of the coating film changes, etc.

[0131] The uneven appearance caused by insufficient scraping of the decorative groove paint can be improved by drastically increasing the amount of paint applied to the design area, but this would cause other problems, such as the gel particles sliding off and slow drying. These various problems caused difficulties in obtaining a coating film with excellent design, and further improvements were required before the coating could be applied to actual painting sites.

[0132] In contrast to this, in the above embodiment, the decorative groove is painted with the water-based paint (M) without curing, so that the curing step can be omitted. When the water-based paint (M) is applied to the decorative groove without any curing, the water-based paint (M) also adheres to the design part, but according to the manufacturing method of the coating film-attached building material of this embodiment, it is possible to obtain a good painted finish appearance without uneven appearance of the design part. The reason for this is thought to be as follows.

[0133] That is, in this embodiment, if the design portion is structured to have fine convex portions of a specific average height and average pitch, when the water-based paint (M) is applied with a spatula or the like, the gel particles (X) can enter the recesses between the fine convex portions or get caught on the fine convex portions, thereby remaining uniformly.

[0134] FIG. 9 is a schematic diagram showing the state after the water-based paint (M) containing the spherical gel particles (X) is applied to the design portion 10 and then scraped off. For example, when a water-based paint containing spherical gel particles 71, 72, and 73 is applied, the gel particles 71, 72, and 73 that have entered the recesses between the minute protrusions 50 are not removed by a spatula or the like that moves along the surface of the design portion 10, and remain in the recesses. The proportions and distribution of the gel particles 71, 72, and 73 that remain in the recesses reflect the proportion of each particle in the gel particles (X) contained in the water-based paint, and are distributed homogeneously.

[0135] FIG. 10 is a schematic diagram showing the state after a water-based paint (M) containing flaky gel particles (X) is applied to a design portion 10 and then scraped off. For example, when a water-based paint containing flake-like gel particles 76, 77, and 78 is applied, gel particles 76, 77, and 78 that get into the recesses between the fine protrusions 50 or get caught on the fine protrusions 50 are not removed by a spatula or the like that moves along the surface of the design portion 10, but remain in the recesses or on the fine protrusions 50. The proportions and distribution of the remaining gel particles 76, 77, and 78 are uniformly distributed, reflecting the proportion of each particle in the gel particles (X) contained in the water-based paint.

[0136] When water-based paint (H) is applied to a design area on which water-based paint (M) has been applied, the areas that cannot be covered by the gel particles (Y) in the water-based paint (H) will have a consistent color tone because each particle is homogeneously distributed, reflecting the proportion of each particle in the gel particles (X), as shown in Figures 9 and 10.

[0137] The most problematic issue is the difference in color tone between the areas covered with the gel particles (Y) in the water-based paint (H) and the areas not covered with the gel particles (Y). In this embodiment, this color difference is made less noticeable by blending gel particles (Y1) of the same color or nearly the same color as the gel particles (X1) in the gel particles (X) with the gel particles (Y).

[0138] In this way, the difference in color tone between the areas covered with the gel-like particles (Y) in the water-based paint (H) and the areas not covered with the gel-like particles (Y) can be made less noticeable, so there is no need to drastically increase the amount of water-based paint (H) to be applied, and problems such as the gel-like particles sliding off or slow drying caused by applying an excessive amount of water-based paint (H) are avoided. Furthermore, since a coating film of the water-based paint (M) with a uniform thickness is not formed on the design part, there is no unevenness in appearance due to the formation of steps compared to other parts or changes in the coating gloss. [Example]

[0139] The present invention will be explained in more detail below based on examples, but the present invention is not limited to these examples.

[0140] <Raw materials> The raw materials used in each example are as follows: ALC board: length 325cm x width 120cm x thickness 15cm.

[0141] Resin: DIC Corporation's "Boncoat (registered trademark) 5400EF", acrylic resin emulsion, solids content 55%. Calcium carbonate A: "NS#2300" manufactured by Nitto Funka Kogyo Co., Ltd., average particle size 1 μm. Calcium carbonate B: Sankyo Seifun Co., Ltd., "G-100", average particle size 65 μm. White pigment: "JR-806" manufactured by Teika Corporation, titanium oxide, average particle size 0.25 μm. Black pigment: Titan Kogyo Co., Ltd., "TAROX (registered trademark) BL-500", black iron oxide pigment, average particle size 0.65 μm.

[0142] Dispersant: Dow Chemical Company, "Orothane® 731A", anionic polymeric dispersant, 25% solids. Thickener A: "QP52000H" manufactured by The Dow Chemical Company, hydroxyethyl cellulose, 1% by mass aqueous solution. Thickener B: San Nopco's "SN Thickener 636", alkali-soluble thickener, active ingredient 30%.

[0143] Film-forming agent: Texanol (registered trademark) manufactured by Eastman Chemical Co. Defoamer: San Nopco's "SN Deformer 1316", 100% solids. Hydrophilic colloid-forming substance: DuPont's "MEYPRO (registered trademark) HPG 8111", a nonionic guar gum derivative, 4% by mass aqueous solution.

[0144] Gelling agent: ammonium borate, 5% by mass aqueous solution, manufactured by Yoneyama Chemical Industry Co., Ltd. Extender pigment: Nippon Talc Co., Ltd., "Talc SSS", hydrated magnesium silicate, 4% by mass aqueous dispersion. Anti-algae agent: Nagase ChemteX Corporation's "HF-260K", active ingredient 30%. Antifungal agent: "Troysan V450" manufactured by arxada JAPAN Co., Ltd., active ingredient 30%. UV absorber: BASF JAPAN Ltd.'s "Tinuvin (registered trademark) 400DW", active ingredient 40%.

[0145] <Preparation of primer paint> Intermediate coatings 1 to 6 were produced by mixing and stirring the raw materials according to the formulations shown in Table 1 in a conventional manner. The prepared primer paint was applied to a hiding power measurement paper at a coating thickness of 10 mil (0.254 mm) and allowed to dry at room temperature for 24 hours. The resulting coating film was measured at 10 randomly selected points using a colorimeter (Konica Minolta, CR-400) and the average value was calculated. The results are shown in Table 1.

[0146] [Table 1]

[0147] <Preparation of gel particle dispersion> [Gel-like particle dispersion 1] A mixed solution (d) was obtained by mixing a resin and a hydrophilic colloid solution according to the formulation shown in Table 2. A mixed solution (e) was obtained by mixing water, a black pigment, and a dispersant according to the formulation shown in Table 2. Next, the mixed solution (d) and the mixed solution (e) were mixed to obtain an emulsion solution (c). Separately, a gelling agent, water, extender pigment, and thickener A were mixed according to the formulation shown in Table 2 to obtain an aqueous solution (f).

[0148] Next, emulsion solution (c) was added to aqueous solution (f) while stirring it with a dissolver (manufactured by Nippon Seiki Seisakusho, rotation speed 1000 rpm). Stirring was continued until the emulsion solution (c) was broken down by stirring and the average particle size became 1 mm to 1 cm, thereby obtaining gel particle dispersion 1.

[0149] [Gel-like particle dispersions 2-6] As shown in Table 2, emulsion solution (c) was obtained in the same manner as gel-like particles 1, except that some or all of the black pigment was replaced with white pigment. The emulsion solution (c) was then finely divided by stirring in the same manner as gel-like particles 1, and stirred until the average particle diameter reached 1 mm to 1 cm, thereby obtaining gel-like particle dispersions 2 to 6.

[0150] [Long diameter and thickness of gel particles] Twenty flake-like gel particles were randomly selected from each of the prepared gel particle dispersions, and their major diameters and thicknesses were measured using a microscope. The arithmetic mean values ​​of the measurements are shown in Table 2.

[0151] [Color measurement of gel particles] First, apply FC Coat Cationic Sealer (a water-based acrylic emulsion cationic sealer manufactured by Fujikura Kasei Co., Ltd.) at a coating weight of 100 g / m. 2 A smooth slate board (300 x 300 x 3 mm) was painted with a roller so that the surface was wet. The primer paint prepared with the formulation shown in Table 1 was applied at a rate of 400 g / m. 2 The gel particle dispersions were spray coated so that the coating was wet, and then dried for 24 hours at a temperature of 23°C and a relative humidity of 50%. Next, each of the prepared gel particle dispersions was placed on a 30-mesh sieve, and the gel particles in the gel particle dispersions were removed.

[0152] Then, 400 g / m of each of the gel particles extracted above was applied to the paint film of the intermediate paint. 2 The coating was sprayed onto the surface to a wet finish and then dried at room temperature for 24 hours. The coating was then applied and dried in the same manner until the base was completely concealed, yielding each gel particle coating film. The resulting coating film was measured at 10 random locations using a colorimeter (Konica Minolta, CR-400) and the average value was calculated. The results are shown in Table 2. The color difference ΔE between the gel particle coating film of Gel Particle Dispersion 1 and the gel particle coating film of Gel Particle Dispersion 2 was also measured. * ab These are also shown in Table 2.

[0153] [Table 2]

[0154] <Preparation of single-color water-based paint> The obtained gel particle dispersion 1 was mixed with an acrylic resin emulsion, an anti-algae agent, an anti-mold agent, an ultraviolet absorber, a thickener, 25% ammonia water, and water according to the formulation shown in Table 3 to obtain a monochrome water-based paint 1 containing gel particle dispersion 1.

[0155] In addition, monochrome water-based paint 2 was obtained in the same manner as monochrome water-based paint 1, except that gel-like particle dispersion 2 was used instead of gel-like particle dispersion 1; monochrome water-based paint 3 was obtained in the same manner as monochrome water-based paint 1, except that gel-like particle dispersion 3 was used; monochrome water-based paint 4 was obtained in the same manner as monochrome water-based paint 1, except that gel-like particle dispersion 4 was used; monochrome water-based paint 5 was obtained in the same manner as monochrome water-based paint 1, except that gel-like particle dispersion 5 was used; and monochrome water-based paint 6 was obtained in the same manner as monochrome water-based paint 1, except that gel-like particle dispersion 6 was used.

[0156] [Table 3]

[0157] <Examples and Comparative Examples> On one side of an ALC board (325cm long x 120cm wide x 15cm thick), a base uneven surface was formed by cutting, in which multiple square (50cm x 50cm) design sections 11 were arranged in a checkerboard pattern, separated by decorative grooves 21 consisting of vertical grooves 21a and horizontal grooves 21b with rectangular cross sections, as shown in Figure 1.

[0158] The widths of the vertical grooves 21a and horizontal grooves 21b (constant width from the opening surface to the bottom surface) and the depths of the decorative grooves were as shown in Tables 4, 5 and 6. Furthermore, numerous convex portions having the average height and average pitch shown in Tables 4, 5, and 6 were formed by cutting on the design portion 11 of the base uneven surface to form the uneven surfaces of each example and comparative example.

[0159] The entire uneven surface was then coated with acrylic resin paint in an amount of 600 g / m as a base treatment.2 The paint was applied with a roller so that the surface was wet, and then the primer paint shown in Tables 4, 5, and 6 was applied in an amount of 300 g / m 2 The building materials were then air-sprayed to a wet finish, and dried for 24 hours at a temperature of 23°C and a relative humidity of 50%. This resulted in the construction materials of each example having an intermediate coating film of any of intermediate coating paints 1 to 6 formed over the entire uneven surface.

[0160] Next, a paint for decorative grooves, prepared by blending the single-color water-based paints 1 to 3 as shown in Tables 4, 5, and 6, was spray-painted into the decorative groove 21 at a coating amount of 400 g / m 2 The decorative groove paint was applied with an air spray so that it was wet. Then, before the decorative groove paint dried, the decorative groove paint adhering to the design portion was scraped off with a silicone rubber spatula. Note that this scraping was omitted only in Comparative Example 2. Thereafter, the paint applied to the decorative groove 21 was dried by drying for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%.

[0161] Next, masking tape was applied to the bottom of the decorative groove 21, and then the single-color water-based paints 1 to 6 prepared according to the formulations shown in Tables 4, 5, and 6 were applied to the design portion in an amount of 400 g / m 2 The paint was applied with an air spray so that the surface was wet, and then dried for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%. After that, the masking tape on the bottom of the groove was peeled off, and the test specimens for each example were obtained.

[0162] In addition, in the paint formulations for the design parts in Tables 4, 5, and 6, blank spaces indicate that the single-color water-based paint in question is not formulated. Tables 4, 5, and 6 also show the color difference ΔE between the intermediate coating film and the gel particle (Y2-1) coating film. * ab This color difference ΔE * ab The colorimetric data of the primer paint film in Table 1 and the colorimetric data of the gel particle paint film in Table 3 were used for the calculation.

[0163] <Evaluation> [Appearance unevenness] The appearance of each test specimen was visually inspected and the unevenness of appearance was evaluated according to the following criteria. The results are shown in Tables 4, 5 and 6.

[0164] (Evaluation criteria) 5: Appearance is very good with no unevenness. 4: Almost no unevenness is observed, and it is good. 3: There is little unevenness and it is at a level sufficient for practical use. 2: There is some unevenness, but it is not a problem for practical use and passes. 1: Uneven appearance, not acceptable.

[0165] [Design] The appearance of each test specimen was visually observed, and the design was evaluated according to the following criteria. The results are shown in Tables 4, 5, and 6. Note that test specimens that received an appearance unevenness rating of 1 were not evaluated for design.

[0166] (Evaluation criteria) 5: The difference in color between the design part and the decorative groove is very large, giving it a three-dimensional, heavy, and highly designed appearance. 4: There is a large difference in color between the design part and the decorative groove, giving it a three-dimensional, heavy, and highly designed appearance. 3: There is a difference in color between the design part and the decorative groove, giving it a three-dimensional, heavy-looking, highly designed appearance. 2: There is a difference in color between the design part and the decorative groove, giving it a good, three-dimensional appearance. 1: There is no difference in color between the design part and the decorative groove, resulting in an appearance with little three-dimensionality.

[0167] [Painting workability] When preparing the test specimens for each example, the paint workability on the substrate was evaluated when the prepared primer paint was applied by air spray. The results are shown in Tables 4, 5, and 6. (Evaluation criteria) 〇: The entire uneven surface can be painted evenly. ×: Uncoated areas remain between the fine convex portions of the uneven surface.

[0168] [Table 4]

[0169] [Table 5]

[0170] [Table 6]

[0171] The decorative groove paint used in each of the above examples corresponds to the water-based paint (M) of the present invention. The single-color water-based paint 1 used to prepare the decorative groove paint contains gel particles derived from gel particle dispersion 1 (corresponding to gel particles (X1) in the present invention). The single-color water-based paint 2 contains gel particles derived from gel particle dispersion 2 (corresponding to gel particles (X2) in the present invention in relation to gel particles (X1)). The single-color water-based paint 5 contains gel particles derived from gel particle dispersion 5 (corresponding to gel particles (X3) in the present specification in relation to gel particles (X1)).

[0172] The paint for the design portion used in each of the above examples corresponds to the water-based paint (H) of the present invention. The single-color water-based paint 1 used to prepare the paint for the design portion contains gel particles derived from the gel particle dispersion 1 (corresponding to the gel particles (Y1) of the present invention in relation to the gel particles (X1) in the paint for the decorative groove). The single-color water-based paints 2 to 6 each contain gel particles derived from the gel particle dispersions 2 to 6 (corresponding to the gel particles (Y2) of the present invention in relation to the gel particles (X1)).

[0173] As shown in Tables 4, 5, and 6, in all Examples, there was no uneven appearance due to the water-based paint (H) coating film showing through in the design area, making the remaining water-based paint (M) stand out. Also, in all Examples, there was no uneven appearance due to the intermediate paint coating film showing through the water-based paint (H) coating film or the water-based paint (M) coating film. Furthermore, in all Examples, there were no problems in all evaluations, including design and painting workability.

[0174] However, in Example 1, the amount of single-color water-based paint 1 in the decorative groove paint was small, and the proportion of gel particles (X1) in the gel particles (X) was low at 1 mass %, so some unevenness due to the color of the gel particles (X2) was observed in the design part, and the uneven appearance was not completely eliminated. In Example 2, the amount of single-color water-based paint 1 in the paint for the design part was small, and the proportion of gel particles (Y1) in the gel particles (Y) was low at 2 mass%, so some unevenness due to the color of the gel particles (X1) was observed in the design part.

[0175] In Examples 4 to 14, the average height of the fine convex portions of the design portion was 120 μm or more, which resulted in further suppression of uneven appearance. For Examples 4 to 10 and 14, the color difference between the coating film of particles corresponding to the gel particles (Y2-1) in the paint for the design part (gel particles with the highest mass proportion among particles corresponding to the gel particles (Y2)) and the intermediate coating film was small, so there was little unevenness in appearance and the design was particularly excellent. For Examples 11 to 14, the greater the color difference between the gel particles corresponding to the gel particles (Y2) in the paint for the design area and the gel particles corresponding to the gel particles (X1) in the paint for the decorative groove, the better the design.

[0176] On the other hand, Comparative Example 1, in which the paint for the design portion did not contain gel particles corresponding to the gel particles (Y1), had uneven appearance. Furthermore, Comparative Example 2, in which the paint for the decorative groove adhering to the design portion was not scraped off, also had uneven appearance.

[0177] In Comparative Example 5, the paint for the design portion did not contain gel particles corresponding to gel particles (Y2), so there was little difference in color between the design portion and the decorative groove, resulting in an appearance with little three-dimensionality.In Comparative Example 3, the total proportion of gel particles corresponding to gel particles (X1) and gel particles (X2) contained in the paint for the design portion was low at 60%, so there was little difference in color between the design portion and the decorative groove, resulting in an appearance with little three-dimensionality.In Comparative Example 4, the proportion of gel particles corresponding to gel particles (Y2) contained in the paint for the design portion was low at 60%, so there was little difference in color between the design portion and the decorative groove, resulting in an appearance with little three-dimensionality. [Explanation of symbols]

[0178] 1~4 Building materials 10~14 Design Department 20~24 decorative groove 30 groove bottom 50~57, 61~63 Convex parts 70-73, 76-78 Gel particles 80 Base material 90 Paint film 91 Dispersion medium 92 Gap

Claims

1. A building material has an uneven surface including a design portion and a decorative groove having a height lower than that of the design portion, Applying a water-based paint (M) to at least the decorative groove without curing the design portion, The water-based paint (M) adhering to the design portion is scraped off before the water-based paint (M) dries, After the coating film of the water-based paint (M) has dried, a water-based paint (H) is applied to the design portion while at least the bottom of the decorative groove is cured. The aqueous coating material (M) contains gel particles (X) including gel particles (X1) and optionally gel particles (X2), The aqueous coating material (H) contains gel particles (Y) including gel particles (Y1) and gel particles (Y2), The gel particles (X2) have a color difference ΔE ＊ ａｂ is greater than 5 and less than 20, The gel particles (X1) and the gel particles (Y1) have a color difference ΔE ＊ ａｂ is 5 or less, The gel particles (X1) and the gel particles (Y2) have a color difference ΔE ＊ ａｂ is 30 or more, the proportion of the gel particles (X1) in the gel particles (X) is 1% by mass or more, the total proportion of the gel particles (X1) and the gel particles (X2) in the gel particles (X) is 70% by mass or more, the proportion of the gel particles (Y1) in the gel particles (Y) is 2 to 19% by mass, A method for producing a coating-coated building material, characterized in that the proportion of the gel-like particles (Y2) in the gel-like particles (Y) is 70 to 98 mass %.

2. The color difference ΔE between the uneven surface before application of the water-based paint (M) and the gel particles (Y2-1) having the highest mass ratio among the gel particles (Y2) is ＊ ａｂ The method for producing a coated building material according to claim 1, wherein the value of the tensile strength of the coated building material is 20 or less.

3. Before applying the water-based paint (M), a step of applying an intermediate paint to the entire uneven surface to form an intermediate paint film is further included, The intermediate coating film and the gel particles (Y2-1) having the highest mass ratio among the gel particles (Y2) have a color difference ΔE ＊ ａｂ The method for producing a coated building material according to claim 1, wherein the value of the tensile strength of the coated building material is 20 or less.

4. The method for producing a coating-provided building material according to any one of claims 1 to 3, wherein the design portion comprises a large number of minute convex portions each having an average height of 120 µm to 3 mm and an average pitch of 700 µm to 9 mm.

5. The method for producing a coating-coated building material according to any one of claims 1 to 3, wherein the heightwise distance between the lowest point of the decorative groove and the lowest point of the design portion is 4 to 25 mm.

6. The method for producing a coating-coated building material according to any one of claims 1 to 3, wherein the width of the opening of the decorative groove is 5 cm or less.

7. The method for producing a coated building material according to any one of claims 1 to 3, wherein the gel particles (X) are flaky and have an average major axis of 500 µm or more and 10 mm or less.

8. The method for producing a coated building material according to any one of claims 1 to 3, wherein the gel particles (X) are in the form of flakes and have an average thickness of 5 µm or more and 1000 µm or less.

9. the gel particles (X) are spherical and have an average major axis of 500 μm or more and 5 mm or less; A method for producing a building material with a coating film according to any one of claims 1 to 3.

10. A building material having an uneven surface consisting of a design portion and a decorative groove that is lower in height than the design portion; a coating film made of an aqueous paint (M) formed at least on the groove bottom of the decorative groove; A coating film made of an aqueous paint (H) formed on the design portion, The coating film made of the aqueous coating material (M) contains gel particles (X) including gel particles (X1) and optionally gel particles (X2), the coating film made of the aqueous coating material (H) contains gel particles (Y) including gel particles (Y1) and gel particles (Y2), the gel particles (X2) have a color difference ΔE*ab from the gel particles (X1) of more than 5 and not more than 20; the color difference ΔE*ab between the gel particles (X1) and the gel particles (Y1) is 5 or less; the color difference ΔE*ab between the gel particles (X1) and the gel particles (Y2) is 30 or more; the proportion of the gel particles (X1) in the gel particles (X) is 1% by mass or more, the total proportion of the gel particles (X1) and the gel particles (X2) in the gel particles (X) is 70% by mass or more, the proportion of the gel particles (Y1) in the gel particles (Y) is 2 to 19% by mass, A coating-film-attached building material, characterized in that the proportion of the gel particles (Y2) in the gel particles (Y) is 70 to 98 mass %.

11. 11. The building material with a coating film according to claim 10, wherein the design portion comprises a large number of minute convex portions each having an average height of 120 μm to 3 mm and an average pitch of 700 μm to 9 mm.

12. 12. The coating-provided building material according to claim 10, wherein the heightwise distance between the lowest point of the decorative groove and the lowest point of the design portion is 4 to 25 mm.

13. 12. The building material with a coating film according to claim 10 or 11, wherein the width of the opening of the decorative groove is 5 cm or less.

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