Powdery coating composition and interior finishing structure

Abstract

To provide a powdery coating composition which enables formation of a film that hardly causes cracks even when coated onto an inner wall to which wallpaper is stuck.SOLUTION: A powdery coating composition enables formation of a coating material by kneaded with water. The coating material is coated onto an inner wall 1 to which wallpaper 3 is stuck through an adhesive material layer 2 and is solidified, and a film 4 is formed. The powdery coating composition contains an extender pigment, a glass fiber and a re-emulsification form powder resin, and 20-100 pts.mass of the glass fiber with respect to 100 pts.mass of the extender pigment.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The technical field of this specification relates to a powdery coating composition for forming a coating to be applied to the surface side of wallpaper pasted on the inner wall of a building, and an interior finishing structure coated and finished with a coating formed from the powdery coating composition.

Background Art

[0002] Conventionally, an interior finish has been known in which wallpaper is pasted on the inner wall of a building and a coating is applied to the surface side of the wallpaper (for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the wallpaper is paper wallpaper (paper cloth) such as kraft paper or Japanese paper, or fabric wallpaper (cloth cloth), in the conventional interior finish, when the coating is applied to the inner wall to which the wallpaper is pasted, the wallpaper expands due to the moisture contained in the coating, and when the coating dries, the wallpaper shrinks, so that the film (coating film) formed from the coating is likely to crack.

[0005] The problem to be solved by the technology of this specification has been made in view of the above points, and an object thereof is to provide a powdery coating composition that forms a film that is less likely to crack even when applied to the inner wall to which the wallpaper is pasted.

Means for Solving the Problems

[0006] The powdery coating composition according to the embodiment of this specification is a powdery coating composition that forms a coating by being kneaded with water, and contains an extender pigment, glass fiber, and a re-emulsified powder resin, and is characterized in that it contains 20 to 100 parts by mass of the glass fiber with respect to 100 parts by mass of the extender pigment.

[0007] Glass fiber is a raw material with strong hydrophilicity, a large specific surface area, and high water retention. According to the powdery coating composition according to the embodiment of this specification, since 20 to 100 parts by mass of glass fiber is contained with respect to 100 parts by mass of the extender pigment, when the powdery coating composition is kneaded with water to form a coating, the glass fiber can retain moisture, and when the coating is applied to the inner wall to which the wallpaper is attached, it is possible to suppress the expansion of the wallpaper due to the moisture contained in the coating. Thereby, it is possible to suppress the occurrence of cracks in the film (coating film) formed from the powdery coating composition.

[0008] Here, in the above powdery coating composition, the average length of the glass fiber can be 0.05 to 2.0 mm, and the aspect ratio can be 10 to 50.

[0009] According to this, the amount of water kneaded into the powdery coating composition can be suitably suppressed, and the occurrence of cracks in the film formed from the powdery coating composition can be suppressed.

[0010] Also, in the above powdery coating composition, the median diameter d50 of the extender pigment can be 2 to 20 μm.

[0011] According to this, the coating workability of the coating formed from the powdery coating composition can be made good.

[0012] Also, in the above powdery coating composition, d84 / d16 derived from the median diameter d16 and the median diameter d84 of the extender pigment can be 6 to 20.

[0013] According to this, when the paint formed from the powder coating composition is applied with a roller, the painting streaks can be made less conspicuous.

[0014] Further, in the above powder coating composition, except for those inevitably contained, it can be made to contain no volatile organic solvent.

[0015] According to this, it is possible to suppress causing harm to people entering and leaving the building where the powder coating composition is applied by the organic solvent.

[0016] Here, the interior finishing structure according to the embodiment has a wallpaper pasted on the inner wall of the building and a film formed from the above powder coating composition that is in close contact with the surface side of the wallpaper, and the wallpaper can be a paper wallpaper.

[0017] According to this, it is possible to suppress cracks caused by the expansion and contraction of the paper wallpaper (paper cloth) due to repeated high humidity and drying.

Effect of the Invention

[0018] According to the powder coating composition of this specification, when applied to the wallpaper, it is possible to suppress the occurrence of cracks in the film formed from the powder coating composition.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0020] Hereinafter, the powdery coating composition and the interior finishing structure according to the embodiments of this specification will be described. Note that the scope of the present invention is not limited to the scope disclosed in the embodiments. As shown in FIG. 1, in the interior finishing structure according to the embodiment, a coating film (coating) 4 is formed on a wallpaper 3 adhered to the inner wall 1 of a building with an adhesive. Note that FIG. 1 is a diagram showing an image of the layer structure of the interior finishing structure coated with the powdery coating composition according to the embodiment, and the thickness of the layers in the figure is different from the actual thickness of the layers. The coating film 4 is formed by applying a paint obtained by kneading the powdery coating composition with water to the wallpaper 3 and solidifying it. The paint composed of the powdery coating composition is applied to the wallpaper 3 with a roller, a brush, or the like. Note that the adhesive layer 2 is formed by solidifying the adhesive for attaching the wallpaper 3.

[0021] The powdery coating composition contains, as raw materials, calcium carbonate as a extender pigment, a re-emulsified powder resin, titanium oxide, glass fiber, a thickener, an antifoaming agent, and a coloring pigment. These raw materials of the powdery coating composition are powdery raw materials, and can be made into a powdery coating composition by mixing them using a powder mixer such as a Nauta mixer or a paddle mixer. Since the powdery coating composition is in powder form, unlike water-based paints, it does not contain organic solvents such as antifreeze agents and film-forming aids except for those inevitably contained. Therefore, it is possible to suppress the harm caused by organic solvents to people entering and leaving the building where the powdery coating composition is applied. Also, since the powdery coating composition is stored in powder form and there is no risk of spoilage, it does not contain a preservative. Therefore, it is highly safe for people handling the powdery coating composition. Table 1 shows a blending example of the powdery coating composition and the preferable ranges (parts by mass) of the other raw materials when calcium carbonate as an extender pigment is 100 (parts by mass).

[0022]

Table 1

[0023] As the extender pigment used in the powder coating composition, common extender pigments such as calcium carbonate, silica sand, talc, and clay can be used. However, in the embodiment, calcium carbonate with a hydrophilic surface was used. The calcium carbonate as the extender pigment in the embodiment has a median diameter d50 (particle diameter at a cumulative distribution of 50 vol%) of 2 to 20 μm as the average particle diameter. Thereby, the coating workability of the coating formed from the powder coating composition is made good. When the median diameter d50 of calcium carbonate is less than 2 μm, there are many fine particles, the viscosity of the coating formed from the powder coating composition is high, and there is a risk that the coating workability with a roller or a brush is poor. On the other hand, when it exceeds 20 μm, there are many coarse particles, and there is a risk that the coarse particles of the film 4 formed from the powder coating composition are conspicuous and the design property is poor. As another embodiment, d50 (median diameter) can be 4 to 15 μm, and as yet another embodiment, 5 to 10 μm.

[0024] The calcium carbonate of the embodiment has a value of d84 / d16, derived from d16 (median diameter, particle diameter at 16 vol% cumulative distribution) and d84 (median diameter, particle diameter at 84 vol% cumulative distribution), in the range of 6 to 20. From d16 to d84 represents the substantial particle diameter width by which calcium carbonate affects the workability of the paint. d84 / d16 is the multiple of the lower end with respect to the upper end of the particle diameter and serves as an index of the width of the particle size distribution. The larger the d84 / d16, the wider the width of the particle size distribution at the center of the particle size distribution. The width of the particle size distribution at the center of the particle size distribution of calcium carbonate affects the occurrence of paint streaks during roller coating of the paint formed from the powder coating composition. Paint streaks refer to the paint streaks at the roller ends that occur in the rolling direction of the roller, and paint marks remain due to the unevenness. When the value of d84 / d16 is in the range of 6 to 20, the paint formed from the powder coating composition containing the calcium carbonate of the embodiment is densely filled with a combination of coarse particles and fine particles, and can form a smooth finish where paint streaks are difficult to visually recognize. When the value of d84 / d16 is less than 6, the width of the particle size distribution at the center of the particle size distribution is narrow, with a bias towards a specific particle size. Due to the particles of the specific particle size with the bias, there is a possibility that paint streaks are likely to occur during the coating of the paint formed from the powder coating composition. On the other hand, when the value of d84 / d16 exceeds 20, the width of the particle size distribution at the center of the particle size distribution is too wide and includes large particles (for example, 200 μm or more). Due to the large particles, there is a possibility that paint streaks occur during the coating of the paint formed from the powder coating composition. As another embodiment, the value of d84 / d16 can be 7 to 16, and as yet another embodiment, it can be 8 to 13.

[0025] A re-emulsifiable powder resin is a fine powder resin obtained by drying a synthetic resin emulsion produced by emulsion polymerization in a particulate state, which re-emulsifies when water is added and stirred. The re-emulsifiable powder resin serves as a binder resin for a powder coating composition, binds raw materials such as calcium carbonate, imparts flexibility to the coating film 4, and enables it to follow the expansion and contraction of the wallpaper 3. Also, since the re-emulsifiable powder resin is a raw material with high water retention, it retains the moisture contained in the paint and has the effect of suppressing the expansion of the wallpaper due to the moisture in the paint. As the re-emulsifiable powder resin, a polymer dispersion for cement admixture and the re-emulsifiable powder resin defined in the Re-emulsifiable Powder Resin (JIS A 6203:2015) can be used. As commercially available products, re-emulsifiable powder resins such as Mobinyl Powder (manufactured by Nippon Coating Resin Co., Ltd.), Sumika Flex (manufactured by Sumitomo Chemical Tex Co., Ltd.), Acronal (manufactured by BASF SE), and ELOTEX (manufactured by Celanese Japan Co., Ltd.) can be used.

[0026] In the powder coating composition of the embodiment, the blending amount of the re-emulsifiable powder resin is 10 to 50 parts by mass with respect to 100 parts by mass of calcium carbonate. This is because it can impart appropriate strength to the coating film 4 formed from the powder coating composition. When the blending amount of the re-emulsifiable powder resin is less than 10 parts by mass with respect to 100 parts by mass of calcium carbonate, the binder content of the coating film 4 formed from the powder coating composition may be insufficient, and the strength of the coating film may be insufficient. On the other hand, if it exceeds 50 parts by mass, due to the characteristics of the re-emulsifiable powder resin, the viscosity of the paint formed from the powder coating composition may increase, and the workability of application with a roller or brush may be poor. As another embodiment, the blending amount of the re-emulsifiable powder resin can be 15 to 40 parts by mass with respect to 100 parts by mass of calcium carbonate, and as yet another embodiment, it can be 20 to 30 parts by mass.

[0027] Titanium oxide is a raw material that imparts hiding power to the film 4 formed from the powder coating composition. In the powder coating composition of the embodiment, the blending amount of titanium oxide is 15 to 50 parts by mass with respect to 100 parts by mass of calcium carbonate. This is because an appropriate hiding power can be imparted to the film 4 formed from the powder coating composition. If the blending amount of titanium oxide is less than 15 parts by mass with respect to 100 parts by mass of calcium carbonate, there is a possibility that sufficient hiding power cannot be imparted to the film 4 formed from the powder coating composition. On the other hand, if it exceeds 50 parts by mass, the effect of enhancing the hiding power may reach a plateau. As another embodiment, the blending amount of titanium oxide can be 20 to 40 parts by mass with respect to 100 parts by mass of calcium carbonate, and as yet another embodiment, it can be 25 to 30 parts by mass. The average particle diameter (d50) of titanium oxide is 0.1 to 0.3 μm, which is far from the particle diameter of calcium carbonate. Therefore, it does not affect the roller (brush) workability.

[0028] Glass fiber is a glass-made fiber that has the heat resistance, incombustibility, and durability of glass, and also has flexibility by exposing recycled glass that has been redissolved to a high temperature of 1300 to 1600°C. In the powder coating composition of the embodiment, 20 to 100 parts by mass of glass fiber is contained with respect to 100 parts by mass of calcium carbonate. Since the glass fiber has a thin fiber diameter, it has a large specific surface area, strong hydrophilicity on the surface, and high water retention. In the powder coating composition of the embodiment, by containing a large amount of glass fiber, the moisture contained in the paint can be retained, and when the paint is applied to the inner wall 1 to which the wallpaper 3 is attached, it is possible to suppress the wallpaper from expanding due to the moisture of the paint, and it is possible to suppress the formation of cracks in the film 4 formed from the paint (powder coating composition). When the content of the glass fiber is less than 20 parts by mass with respect to 100 parts by mass of calcium carbonate, the amount of water that can be retained is small, and there is a risk that the wallpaper 3 will expand and the cracks in the film 4 cannot be suppressed. On the other hand, if it exceeds 100 parts by mass, there are many glass fibers contained in the film 4 formed from the powder coating composition, and the glass fibers may get entangled with the roller or brush, resulting in poor coating workability. As another embodiment, the content of the glass fiber can be 25 to 70 parts by mass with respect to 100 parts by mass of calcium carbonate, and as yet another embodiment, 30 to 50 parts by mass. In addition, due to the water retention of the glass fiber, the powder coating composition can be made such that no surfactant needs to be blended.

[0029] In the embodiment, the fiber diameter of the glass fiber can be 1 to 200 μm. This is because the surface area of the glass fiber can be ensured and the moisture contained in the paint can be sufficiently retained. If the fiber diameter of the glass fiber is less than 1 μm, there are few general-purpose products and it is difficult to use. On the other hand, if it exceeds 200 μm, the surface area of the glass fiber is small, and there is a risk that it will be difficult to sufficiently retain the moisture contained in the paint. As another embodiment, the fiber diameter of the glass fiber can be 2 to 100 μm.

[0030] In the embodiment, the average length of the glass fibers is 0.05 to 2.0 mm, and 90 vol% or more is 1.5 mm or less. This is intended to enhance the resistance of the coating film 4 formed from the powder coating composition to cracking. As another embodiment, 90 vol% or more of the glass fibers can have a length of 1.0 mm or less, and as yet another embodiment, 90 vol% or more can have a length of 0.5 mm or less. Note that the aspect ratio of the glass fibers in the embodiment is 10 to 50.

[0031] The thickener is a material added to adjust the workability during the application of the paint formed from the powder coating composition and to prevent sagging. Since the powder coating composition is in powder form, a powdery thickener can also be used. As the thickener, methyl cellulose (MC), hydroxyethyl cellulose (HEC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), etc. can be selected and added as appropriate.

[0032] The defoaming agent is a material added to remove air bubbles from the paint formed from the powder coating composition and to densify the coating film 4 formed from the powder coating composition. As the defoaming agent, a powdery defoaming agent can be appropriately selected and an appropriate amount can be added. The coloring pigment is a material added to impart color to the coating film 4 formed from the powder coating composition. As the coloring pigment, a powdery coloring pigment can be appropriately selected and an appropriate amount can be added.

[0033] The powder coating composition becomes a paint by kneading with kneading water. The kneading water is 75 to 80 parts by mass with respect to 100 parts by mass of the powder coating composition. The paint composed of the powder coating composition is applied to the surface side of the wallpaper 3 pasted on the inner wall 1 of the building.

[0034] On the inner wall 1 of a building where a paint composed of a powder coating composition is applied, there are the inner wall 1 of the building's structure, partition walls, etc. As the boards (plates) constituting the partition walls, the interior finishing structure of the embodiment can be applied to gypsum boards (including plasterboards), calcium silicate boards, wood plywood, fiber-reinforced cement boards, etc. As another embodiment, it can be applied to gypsum boards. On the inner wall 1, wallpaper 3 is pasted with an adhesive. As the adhesive for pasting the wallpaper 3 on the inner wall 1, an adhesive with the formulation described in Table 2 was used.

[0035]

Table 2

[0036] In the embodiment, the wallpaper 3 can be applied without being limited to the type of its material. As another embodiment, it can be a paper wallpaper (paper cloth) made by papermaking pulp-derived fibers such as kraft paper or Japanese paper. Also, as another embodiment, Japanese paper can be used as the paper wallpaper. This is because Japanese paper has little expansion and contraction due to water absorption. As the Japanese paper, Japanese paper with wood powder strained on one side can be used. This is because the wood powder causes irregularities on the paper wallpaper, making it difficult to notice the paint streaks of the paint formed from the powder coating composition and the unevenness of the transfer pattern by the roller. Note that the unevenness of the transfer pattern by the roller is the variation of the pattern caused by the difference in the transfer pattern for each stroke of the roller, which is seen when applying multiple coats. The pasting of the paper wallpaper to the inner wall 1 is carried out by butting adjacent paper wallpapers against each other so that the wallpaper 3 is integrated. As another embodiment, a gap of 0.1 - 2 mm can be provided between adjacent paper wallpapers to paste the paper wallpapers. This is because the gap between the paper wallpapers is not noticeable, so there is no risk of inferior aesthetics, and when applying the paint composed of the powder coating composition of the embodiment, it is possible to further suppress the occurrence of cracks in the film 4 formed by the paint composed of the powder coating composition due to the expansion and contraction of the paper wallpaper. As yet another embodiment, the gap between adjacent paper wallpapers can be 0.1 - 1 mm.

[0037] Next, a method for applying a paint composed of the powdery paint composition of the embodiment will be described. The powdery paint composition of the embodiment becomes a paint by kneading with kneading water. The paint can be applied to the inner wall 1 to which the wallpaper 3 is attached using a roller, a brush, or the like. The application amount is 100 to 125 g / m in terms of powder (non-volatile content). 2 (single coating). The number of coating times can be single coating or double coating, and for maintaining concealment, it can be double coating.

[0038] The interior finishing structure constructed in this way has a film 4 formed by a paint composed of a powdery paint composition on a paper wallpaper as the wallpaper 3 attached to the inner wall 1 of the building by an adhesive. Since the film 4 of the interior finishing structure contains a synthetic resin (re-emulsified powder resin), it can follow various movements of the inner wall 1 and the paper wallpaper, and since the coating film 4 contains glass fibers, it is possible to suppress the occurrence of cracks against these movements.

Examples

[0039] Regarding the powdery paint compositions with different formulations of the powdery paint composition of the embodiment, 75 parts by mass of water was mixed with 100 parts by mass of the powdery paint composition to make a paint. The paint was applied onto Japanese paper (with wood powder), Japanese paper (without wood powder), or kraft paper as a paper wallpaper attached to a gypsum board (manufactured by Yoshino Gypsum) with an adhesive having the formulation described in Table 2 using a wool roller so as to have an application amount of 250 g / m 2 (total amount for double coating), and the evaluations (tests) described below were conducted. Examples and comparative examples of the powdery paint composition are shown in Table 3. Note that the paper wallpapers are those where the paper wallpapers are butted against each other and attached on the gypsum board.

[0040] Coating workability The coating workability was evaluated for the workability when applying using a wool roller. And the test results were evaluated as ○ for those that can be applied without difficulty, △ for those that can be applied but the roller feels heavy, and × for those that are difficult to apply due to poor rolling of the roller.

[0041] Cracks in the wallpaper joint Regarding cracks in the wallpaper joint, after the paint solidified, those with no visible cracks along the joint of the paper wallpapers were evaluated as ○, those where no cracks were initially visible but cracks were confirmed upon close inspection were evaluated as △, and those with visible cracks were evaluated as ×.

[0042] Appearance of streaks due to painting Regarding the appearance of streaks due to painting, those with no visible painting streaks were evaluated as ◎, those where painting streaks were visible upon close inspection but were not visible when observed from a distance of 30 cm or more were evaluated as ○, those where painting streaks were visible but were not visible when observed from a distance of 1 m or more were evaluated as △, and those with visible painting streaks even when observed from a distance of 1 m or more were evaluated as ×.

[0043] Unevenness of the transferred pattern due to painting Regarding the unevenness of the transferred pattern due to painting, those with a uniform transferred pattern were evaluated as ◎, those with variations in the transferred pattern but appearing generally uniform when observed from a distance of 30 cm or more were evaluated as ○, those with variations in the transferred pattern but appearing generally uniform when observed from a distance of 1 m or more were evaluated as △, and those with visible variations in the transferred pattern were evaluated as ×.

[0044] Appearance of wrinkles due to painting Regarding the appearance of wrinkles due to painting, those with no wrinkles were evaluated as ◎, those with wrinkles immediately after painting but the wrinkles becoming invisible after drying were evaluated as ○, those with wrinkles immediately after painting and still having slight visible wrinkles after drying were evaluated as △, and those with visible wrinkles even after drying were evaluated as ×.

[0045]

Table 3

[0046] Details of the raw materials are described below.

[0047] Calcium carbonate A d50 = 6.1 μm d16 = 1.5 μm d84 = 14.5 μm d84 / d16 = 9.7 The particle size distribution of calcium carbonate A is shown in Figure 2.

[0048] Calcium carbonate B d50 = 21.5 μm d16 = 7.2 μm d84 = 40.0 μm d84 / d16 = 5.6 The particle size distribution of calcium carbonate B is shown in Figure 3.

[0049] Glass fiber A Average fiber length: 0.1 mm Aspect ratio: 10 Glass fiber B Average fiber length: 0.07 mm Aspect ratio: A mixture of 10 to 50 The re-emulsified powder resin used a re-emulsified powder acrylic resin, and for titanium oxide, thickener, defoamer and coloring pigment, commercially available products were selected and used respectively.

[0050] (Examples 1 to 3) Examples 1 to 3 are examples using the same powdery paint composition using calcium carbonate A and glass fiber A. The wallpaper to be coated is Japanese paper (with wood powder) for Example 1, Japanese paper (without wood powder) for Example 2, and kraft paper for Example 3. The coating workability was such that it could be coated without difficulty. As for the finish, although it was not possible to confirm when observing Examples 2 and 3 separated by 30 cm or more, the occurrence of streaks due to painting and unevenness of the transferred pattern could be confirmed. In Example 1 (Japanese paper (with wood powder)), it was difficult to visually recognize the painting streaks and the unevenness of the transferred pattern by the roller due to the wood powder in the Japanese paper. No cracks were confirmed along the butted parts of the wallpapers in Examples 1 to 3. In Example 3 (kraft paper), wrinkles due to the moisture of the paint occurred on the kraft paper, and the wrinkles could still be slightly visually recognized even after drying.

[0051] (Example 4) Example 4 is an example in which calcium carbonate in Example 1 was changed to calcium carbonate B with d84 / d16 = 5.6. The coating workability allows for easy coating. The finish has no cracks, unevenness in the transferred pattern, or wrinkles, but when observed at intervals of 1 m or more, although it is not noticeable, coating streaks were confirmed along the coating direction of the roller.

[0052] (Examples 5, 6) Examples 5 and 6 are examples in which the blending amount of glass fiber was reduced from Example 1. The coating workability allows for easy coating, and no cracks or wrinkles were confirmed along the butting parts of the paper wallpapers. For the finish, the coating streaks and unevenness in the transferred pattern due to the roller were less visible due to the wood powder of the Japanese paper. Note that Example 6 is a powder coating composition containing a coloring pigment.

[0053] (Example 7) Example 7 is an example in which the blending amount of glass fiber was increased from Example 1. The workability allows for problem - free coating, but the roller felt heavy.

[0054] (Example 8) Example 8 is a modification in which the glass fiber in Example 1 was changed to glass fiber B, which is a mixture with an average fiber length of 0.07 mm and an aspect ratio of 10 - 50, and the blending amount was increased. The workability allows for problem - free coating, but the roller felt heavy. The finish had no cracks or wrinkles along the butting parts of the paper wallpapers, had a smooth finish, and due to the wood powder of the Japanese paper, the coating streaks and unevenness in the transferred pattern due to the roller were less visible. Although not confirmed within the scope of the test, it is presumed that Example 8 can better follow various movements of the inner wall 1 and the paper wallpapers because it uses glass fiber B, which is a mixture with an aspect ratio of 10 - 50.

[0055] (Comparative Example 1) Comparative Example 1 does not contain glass fibers. Therefore, Comparative Example 1 cannot suppress the expansion of the paper wallpaper due to the moisture contained in the paint, and cracks have occurred along the butting portions of the paper wallpapers due to the expansion and contraction of the paper wallpapers. Note that the occurrence of wrinkles due to painting was not confirmed.

[0056] (Comparative Example 2) Comparative Example 2 does not contain a re-emulsified powder resin. Since Comparative Example 2 does not contain a re-emulsified powder resin, it cannot suppress the expansion of the paper wallpaper due to the moisture contained in the paint, and cracks have occurred along the butting portions of the paper wallpapers due to the expansion and contraction of the paper wallpapers. Note that although a film 4 was seemingly formed in Comparative Example 2, there was no binder in the film 4, and the film 4 would fall off when subjected to an external force.

[0057] (Comparative Example 3) Comparative Example 3 is obtained by further reducing the blending amount of glass fibers from Example 5. Cracks along the butting portions of the paper wallpapers were confirmed in the finish. Note that the occurrence of wrinkles due to painting was not confirmed.

Explanation of Reference Numerals

[0058] 1... Inner wall, 2... Adhesive layer, 3... Wallpaper, 4... Film.

Claims

1. A powdery coating composition that forms a coating when kneaded with water, comprising an extender pigment, glass fibers, and a re-emulsified powder resin, characterized in that it contains 20 to 100 parts by mass of the glass fibers with respect to 100 parts by mass of the extender pigment.

2. The powdery coating composition according to Claim 1, characterized in that the average length of the glass fibers is 0.05 to 2.0 mm and the aspect ratio is 10 to 50.

3. The powdery coating composition according to Claim 1, characterized in that the median diameter d50 of the extender pigment is 2 to 20 μm.

4. The powdery coating composition according to Claim 3, characterized in that d84 / d16, derived from the median diameter d16 and the median diameter d84 of the extender pigment, is 6 to 20.

5. The powdery coating composition according to Claim 1, characterized in that it does not contain volatile organic solvents except for those inevitably contained.

6. An interior finishing structure comprising wallpaper attached to the inner wall of a building and a film formed from the powdery coating composition according to Claim 1 adhered to the surface side of the wallpaper, wherein the wallpaper is paper wallpaper.

Images