JP7270362B2 - Water-based coating material composition and jointless finishing method for exterior walls using the same - Google Patents

Description

The present invention relates to a one-liquid water-based coating composition that is applied to the outer wall of a building to a thickness of 2 to 5 mm, and imparts design properties and heat insulation properties consisting of various uneven patterns to the outer wall. A jointless exterior wall that can be finished without joints by applying the water-based coating material composition to the surface of the butted portion of the exterior wall where the side ends of the exterior wall materials are attached to the base. It relates to the finishing method.

Conventionally, a composition for coating other facilities such as roofs, outer walls, and inner walls of buildings, especially as a coating material with heat insulation, waterproof and sound insulation for forming a heat insulation layer, A heat-insulating coating material comprising hollow beads, an acrylic resin emulsion, and a function-retaining agent, wherein the hollow beads account for 45 to 50% by volume of the total volume, and the function-retaining agent is a high-boiling oil and a viscous A heat-insulating coating material has been proposed which is characterized by containing a modifier, a film-forming aid and an antifoaming agent (Patent Document 1).

However, the heat-insulating coating material shown in Patent Document 1 has an extremely small average particle diameter of hollow beads of about 5 to 15 μm (paragraph 0020 of the specification of Patent Document 1), and the coating thickness as a coating material is 0.6 mm. 0032 of the same paragraph), it is difficult to apply the heat insulating coating material to a thickness of 2 to 5 mm to impart a design property.

On the other hand, as a jointless structure of the outer wall, a plurality of outer wall materials are attached to the base material with their side ends butted against each other, and the surface side of the butted part of the side ends is covered with an elastic joint treatment material. In addition, a multi-hole sheet having a large number of holes and through which the elastic joint treatment material can penetrate is arranged inside the elastic joint treatment material, and an elastic paint is applied to the surface of the elastic joint treatment material. The multi-hole sheet consists of a long diameter portion along the joint line formed by butting the side ends of the exterior wall material and a long diameter portion perpendicular to the joint line A jointless outer wall characterized by having an opening portion along the direction and having a short diameter portion shorter than the long diameter portion, and the number of openings per 1 cm ² in the multi-hole sheet is 10 to 60. A structure has been proposed (Patent Document 2).

However, the jointless structure of the outer wall shown in Patent Document 2 requires the use of an elastic joint treatment material and the placement of a specific multi-hole sheet through which the elastic joint treatment material can penetrate, followed by finishing with an elastic coating material. Therefore, there is a problem that construction takes time.

JP-A-2008-95031 JP-A-2002-146990

It is an object of the present invention to apply a coating of 2 to 5 mm thickness to an outer wall to provide a design with various uneven patterns and heat insulation, and a plurality of outer wall materials can be butted against each other at their side ends. To provide a water-based coating material composition which does not cause cracks due to expansion and contraction of the butting parts even when applied to the butting parts of an outer wall attached to a base, and to use the water-based coating material composition. In the case of an outer wall in which a plurality of outer wall materials are attached to the base with their side ends butted against each other, there is a complicated specification in which elastic joint fillers and multi-hole sheets are used in the butted portions and then covered with elastic paint. To provide a jointless finishing method for an outer wall which is unnecessary and easy to construct.

In order to solve the above problems, the invention according to claim 1 provides an acrylic resin emulsion, a filler, an aggregate, a pigment, a thickener, a film formation aid, an inorganic hollow filler, and a length Composed of vinylon fibers of 2 to 7 mm and water, with respect to 100 parts by weight of the entire composition, 20 to 30 parts by weight of inorganic hollow filler, 0.2 to 0.4 parts by weight of vinylon fibers, acrylic resin A water-based coating material composition characterized in that the resin solid content in the emulsion is 5 to 20 parts by weight, and that it is possible to apply the composition with a coating thickness of 2 to 5 mm to impart a design property of an uneven pattern. I will provide a.

The invention according to claim 2 provides the water-based coating material composition according to claim 1, wherein the inorganic hollow filler comprises a spherical foam of volcanic fine-grained vitreous tuff and a glass foam. .

In the invention according to claim 3, the inorganic hollow filler is a spherical foam of volcanic fine-grain vitreous tuff with an average particle size of 200 to 400 μm and a glass foam with an average particle size of 1.0 to 1.4 mm. To provide a water-based coating material composition according to claim 1 or claim 2, comprising:

According to a fourth aspect of the present invention, a plurality of exterior wall materials are mounted on a substrate with their side ends butted against each other, and the surfaces of the butted portions of the side ends are coated with the outer wall material according to any one of claims 1 to 3. A jointless finishing method for an outer wall in which a water-based coating composition is applied to provide a jointless finish, in which a sealer is applied to the surface of the butted portion if necessary, and then any one of claims 1 to 3. The water-based coating material composition according to any one of claims 1 to 3 is applied to a coating thickness of 2 to 5 mm to adjust the unevenness of the butted part, and then the water-based coating material composition according to any one of claims 1 to 3. To provide a jointless finishing method for an outer wall characterized by finishing by coating with a coating thickness of 2 to 5 mm.

The invention according to claim 5 provides a jointless finishing method for an outer wall according to claim 4, characterized in that a sand wall-like paint composition is further applied.

The invention according to claim 6 provides the jointless finishing method for an outer wall according to claim 5, wherein the sand wall-like coating composition has a heat shielding property.

The water-based coating material composition of the present invention has the effect of imparting design properties and heat insulation by applying a 2 to 5 mm thickness to an outer wall. Also, even if a plurality of exterior wall materials are butted against each other at their side ends and applied to the abutted portions of the exterior walls attached to the substrate, there is an effect that cracks do not occur due to expansion and contraction of the abutted portions.

In addition, in the jointless finishing method for an outer wall of the present invention, the water-based coating material composition according to any one of claims 1 to 3 is applied to the surface of the butted portion of the outer wall material to make the outer wall jointless. There is an effect that it can be finished in a state, and there is an effect that even if the butted portion expands and contracts, the coating film formed by the water-based coating material composition does not crack.

The present invention will be described in detail below.

The water-based coating material composition of the present invention comprises an acrylic resin emulsion, a filler, an aggregate, a pigment, a thickener, a film forming aid, an inorganic hollow filler, and vinylon having a length of 2 to 7 mm. Composed of fibers and water, with respect to 100 parts by weight of the entire composition, 20 to 30 parts by weight of inorganic hollow filler, 0.2 to 0.4 parts by weight of vinylon fiber, and resin solids in the acrylic resin emulsion It is a water-based coating material composition characterized in that the amount is 5 to 20 parts by weight and can be applied with a coating thickness of 2 to 5 mm to impart a design property consisting of an uneven pattern. An antifoaming agent, a dispersing agent, etc. can be blended accordingly.

[Acrylic resin emulsion]
For the acrylic resin emulsion of the present invention, an acrylic resin emulsion such as an acrylic ester copolymer resin, a vinyl acetate/acrylic ester copolymer resin, or a silicone-modified acrylic resin can be used. Examples of acrylic monomers for acrylic resins include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, t-butyl acrylate, hexyl acrylate, and 2-ethylhexyl. Acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, n-amyl acrylate, isoamyl acrylate, lauryl acrylate, stearyl acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl ( meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl ( meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, n-amyl (meth)acrylate, isoamyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl ( Meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, methoxypropyl (meth)acrylate, ethoxypropyl (meth)acrylate, etc. can be used. I can. Other unsaturated monomers include styrene derivatives such as styrene, α-methylstyrene, chlorostyrene, vinyltoluene, methoxystyrene; (meth)acrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, anhydride; Carboxyl group-containing monomers such as itaconic acid and crotonic acid; (meth)acrylic acid, crotonic acid, itaconic acid; 2-hydroxyethyl (meth)acrylate and 2(3)-hydroxypropyl (meth)acrylate, 4-Hydroxybutyl acrylate, allyl alcohol, hydroxyl group-containing monomers such as mono (meth) acrylic acid esters of polyhydric alcohols; (meth) acrylamide, amide group-containing monomers such as maleamide; 2-aminoethyl ( meth) acrylate, dimethylaminoethyl (meth) acrylate, 3-aminopropyl (meth) acrylate, 2-butylaminoethyl (meth) acrylate, amino group-containing monomers such as vinylpyridine; glycidyl (meth) acrylate, Allyl glycidyl ether, epoxy group-containing monomers and oligomers obtained by reacting an epoxy compound having two or more glycidyl groups with an ethylenically unsaturated monomer having an active hydrogen atom; vinyltrimethoxysilane, vinyltriethoxy silane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 2-(meth)acryloxyethyltrimethoxysilane, 2 -(meth)acryloxyethyltriethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acryloxypropylmethyldipropoxysilane, 3 -Alkoxysilyl group-containing monomers such as (meth)acryloxybutylphenyldimethoxysilane, 3-(meth)acryloxypropyldimethylmethoxysilane, and 3-(meth)acryloxypropyldimethylmethoxysilane; in addition, vinyl acetate, Vinyl chloride, as well as ethylene, butadiene, acrylonitrile, dialkyl fumarate, etc. can be used.

The glass transition temperature of the resin in the acrylic resin emulsion is preferably -30 to 40°C. If the glass transition temperature is less than −30° C., the finished surface becomes tacky and easily soiled, and if it exceeds 40° C., poor film formation occurs. The resin solid content in the entire water-based coating material composition of the present invention is preferably 5.0 to 20.0% by weight. %, the viscosity decreases, the coating workability decreases, and the number of designs (patterns) that can be expressed decreases. A commercially available acrylic resin emulsion is Acronal PS743 (manufactured by BASF, solid content: 55% by weight).

[Filling material]
The filler used in the present invention has an average particle diameter D ₅₀ (particle diameter of 50% accumulated by weight) of less than 100 μm, and is blended for the purpose of adjusting the viscosity and applicability of the composition. Calcium carbonate, clay, kaolin, talc, precipitated barium sulfate, barium carbonate, silica sand powder, etc. can be used, and heavy calcium carbonate is inexpensive and can reduce the cost burden. The amount of the filler compounded is 3 to 20% by weight, preferably 5 to 12% by weight, based on the total coating material composition. %, the viscosity of the coating material increases and the coating workability becomes poor. If it is less than 3% by weight, the opacity may be lowered depending on the color tone.

[aggregate]
The filler used in the present invention has an average particle size D ₅₀ (particle size of 50% accumulated by weight) of 100 μm or more, and is blended for the purpose of imparting unevenness to the finished surface. If the diameter is 100 μm or more, the particle diameter can be arbitrarily selected. For example, silica sand, glass, silica, talc, heavy calcium carbonate, etc. can be used. As such, there is K-250 (trade name, manufactured by Asahi Komatsu Co., Ltd.). The amount of the aggregate (B) is 20 to 40% by weight based on the total composition. If it is less than 20% by weight, the design (roughness of the coating material) is insufficient, and if it exceeds 40% by weight, workability is reduced. .

[Pigment]
As pigments, inorganic pigments such as titanium oxide, zinc oxide, carbon black, ferric oxide (rouge), lead chromate, yellow lead, and yellow iron oxide can be used. It can be used as a main pigment because it has excellent properties and is white.

[Thickener]
The thickener is blended for the purpose of improving trowel coating workability and water retention, and water-soluble cellulose ether, urethane-modified polyether, polycarboxylic acid, and the like can be used. As a water-soluble cellulose ether, there is hi METOLOSE 90SH15000 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name). The blending amount of the thickener is preferably 0.1 to 5.0 parts by weight per 100 parts by weight of the entire composition. If it exceeds 5.0 parts by weight, the coating workability is lowered.

[Film formation aid]
Ethylene glycol diethyl ether, benzyl alcohol, butyl cellosolve, ester alcohol, etc. should be used as the film-forming aid to promote the fusion of polymer particles in the emulsion and form a uniform polymer film. can be done. The amount of the film formation aid is preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the entire composition. If the amount is more than 100%, dirt may easily adhere to the surface of the coating material.

[Inorganic hollow filler]
The inorganic hollow filler used in the present invention imparts heat insulation to the coating film that has been applied with the water-based coating composition and dried and cured, and the side edges of a plurality of exterior wall materials are butted against each other. Even if the present composition is applied directly above the gap between the substantially straight butted parts formed by mounting on the outer wall material, it does not cause thinning, and the gap is not affected by temperature changes and vibrations of the outer wall material. It is blended for the purpose of imparting flexibility that can follow the movement even if it expands and contracts due to In the present invention, the inorganic hollow filler not only imparts thermal insulation properties, but also imparts flexibility to the coating film, so that the outer wall material (generally referred to as siding material) can be vertically and horizontally attached to the base. A major feature is that the large-area outer wall formed by bonding is made into a single large outer wall without any gaps and in which problems such as cracks do not occur in the gaps.

In order to achieve the above object, in the present invention, an inorganic hollow filler is blended in a large amount of 20 to 30 parts by weight with respect to 100 parts by weight of the entire composition, and in addition, the length of 2 to 2 as described in detail below is added. A 7 mm vinylon fiber is compounded.

As the inorganic hollow filler, any inorganic hollow filler may be used as long as it achieves the above purpose. A glass foam having a bulk specific gravity of 0.2 to 0.6 g / cc and a gap between the glass foam when dispersed in a coating material are filled with a slightly small average particle size of 200 to 200. By using the two types of inorganic hollow fillers in combination so as to be filled with spherical foams of volcanic fine-grained vitreous tuff having a bulk density of 0.1 to 0.3 g/cc and a size of 400 μm, the above purpose can be achieved more reliably. achieved. The average particle size here means the average particle size _D50 at which the weight accumulation is 50%.

If the average particle diameter of the glass foam is less than 1.0 mm, the heat insulating property is insufficient, and if it exceeds 1.4 mm, cracks may occur in the coating material due to movement of the gaps. If the average particle size of the spherical foam of volcanic fine-grained vitreous tuff is less than 200 µm, the thermal insulation is insufficient, and if it exceeds 400 µm, cracks tend to occur in the coating material.

[Vinylon fiber]
The vinylon fiber used in the present invention is intended to prevent cracks or the like from occurring in the composition applied over the gaps when the outer wall material used as the base material is greatly moved due to heat or vibration. Blend. Vinylon fibers with a length of 2 to 7 mm are used. If the length is less than 2 mm, cracks may occur in the coating film. . The fineness of the vinylon fiber is not particularly limited as long as it can prevent cracks or the like from occurring in the composition, and vinylon fibers of 0.5 to 6 dtex can be used.

The vinylon fiber content is 0.2-0.4 parts by weight per 100 parts by weight of the composition. If it is less than 0.2 parts by weight, cracks may occur in the coating film. The workability when applying the material to the substrate decreases.

The water-based coating material composition of the present invention can be applied to a mortar base, etc. In this case, even if fine cracks occur in the mortar base, cracks do not occur in the coating film due to the movement of the cracks. . When a plurality of exterior wall materials are attached to a substrate with their side ends butted against each other, and the water-based coating composition is applied to the surfaces of the exterior wall materials, the surfaces of the butted portions may be coated with the following if necessary. Apply a sealer to prevent the water-based coating composition of the present invention from being absorbed, then apply the water-based coating composition to a thickness of 2 to 5 mm to adjust the unevenness of the butted part, Furthermore, the same water-based coating material composition is applied to a thickness of 2 to 5 mm to finish. By doing so, the gap joints formed vertically and horizontally by a plurality of exterior wall materials can be covered and hidden, resulting in a jointless exterior wall finishing method.

As an upper layer of the water-based coating material composition of the present invention, for example, a sand wall-like coating composition as proposed in Japanese Patent No. 4721935, paragraph 0042, Table 1, Examples 1 to 5, can be applied. As a result, even if the present composition discolors over time, it is possible to easily recover the aesthetic appearance by applying the sand wall-like coating composition. Further, if the sand wall-like coating composition is imparted with a heat insulating property, the heat insulating property and the heat insulating property of the water-based coating material composition of the present invention further suppress the temperature rise inside the building.

In addition to the above ingredients, the composition may contain an antifoaming agent to eliminate bubbles caused by entrainment in the coating material, and a dispersant to uniformly disperse fillers, pigments, etc. There is

When applying the water-based coating composition of the present invention, a roller brush, pattern roller, iron trowel, spray gun, etc. are used to appropriately select a construction tool so as to achieve the desired design. Finish with a moderate amount of paint. Appropriate viscosity of the blended water-based coating composition is preferably 300 to 700 Pa·s, and such a viscosity can be adjusted by adding an appropriate amount of water.

The coating thickness of the water-based coating material composition of the present invention is 2 to 5 mm, and the desired design is imparted using the roller brush, pattern roller, iron trowel, spray gun, or the like.

Examples and comparative examples will be described below in detail.

[Preparation of materials]
According to the formulations in Table 1, water-based coating compositions of Formulations A to E were prepared. In Table 1, the acrylic resin emulsion is Acronal PS743 (solid content: 54 to 56%, glass transition temperature of resin: 30°C, copolymer of styrene, acrylic acid ester, and methacrylic acid ester, manufactured by BASF, trade name). The filler is silica sand powder #300 (average particle size 25 μm, manufactured by Tochu Co., Ltd., trade name), and the aggregate is Tohoku silica sand No. 7 (specific gravity 1.5, average particle size 150 μm, Tohoku silica sand Co., Ltd., trade name), titanium oxide R-820 (Ishihara Sangyo Co., Ltd., trade name) is used as the pigment, and the thickener is water-soluble cellulose ether hi Metrose 90SH-15000 (Shin-Etsu Chemical Co., Ltd. company's product name), the film forming aid is Texanol CS-12 (manufactured by Chisso Corporation, product name), and the inorganic hollow filler A has an average particle size of 1.2 mm and a bulk specific gravity of 0.4 g/cc. The glass foam JF-215 (trade name, manufactured by Aica Kogyo Co., Ltd.) is used, and the inorganic hollow filler B is a spherical foam JF-216 of volcanic fine-grained vitreous tuff having an average particle size of 300 μm and a bulk specific gravity of 0.2 g/cc. (trade name, manufactured by Aica Kogyo Co., Ltd.), and as the vinylon fiber, vinylon fiber JF-214 (trade name, manufactured by Aica Kogyo Co., Ltd.) having a length of 4 mm and a fineness of 2.0 dtex was used. In addition, an antifoaming agent and a dispersing agent are added, and these can be appropriately selected from commercially available products for water-based coating materials. These raw materials were uniformly mixed and dispersed to obtain formulations A to E of water-based coating material compositions.

[Examples and Comparative Examples]
In Example 1, the water-based coating material composition of coating material formulation A in Table 1 was used, and the base was coated twice with a thickness of 3.5 mm to give a total thickness of 7.0 mm. Example 2 is a sand wall-like coating composition Aika Jollipat JQ-810 (trade name, manufactured by Aika Kogyo Co., Ltd., patent No. 5721935, paragraph 0042 shown in Table 1), which has heat-shielding properties in addition to the coating film of Example 1. Titanium oxide R-820 of Example 1 was replaced with infrared shielding titanium oxide JR-1000 (manufactured by Tayca, average particle size 1.0 μm)) was applied twice at 0.2 to 0.4 kg / m ² bottom. Example 3 uses the water-based coating material composition of coating material formulation A, is applied twice to a thickness of 2.5 mm on the base to make a total thickness of 5.0 mm, and has heat shielding properties as in Example 2. Sand wall-like coating composition Aika Jollipat JQ-810 was applied twice at 0.2 to 0.4 kg/m ² . Comparative Example 1 uses the water-based coating material composition of coating material formulation B and applies it twice to the base to a thickness of 3.5 mm to make a total thickness of 7.0 mm. Comparative Example 2 is a water-based coating material of coating material formulation C. Using the composition, apply twice to the base with a thickness of 3.5 mm to make a total thickness of 7.0 mm. was applied twice to give a total thickness of 7.0 mm. In Comparative Example 4, the water-based coating material composition of coating material formulation E was applied to a thickness of 2 mm.

Examples and comparative examples were evaluated by the following evaluation methods.

[Evaluation method]

[Coating workability]
A 900 mm square flexible board conforming to JISA 5430 is installed vertically, and when creating a coating film of an example or a comparative example, the coating thickness is 2 to 5 mm while applying a water-based coating composition with a trowel tip to make a difference in unevenness. Attach a fan-shaped handle so that it becomes In this case, the case where the tip of the trowel can be moved smoothly was evaluated as ◯, the case where the tip of the trowel was somewhat difficult to move was evaluated as Δ, and the case where the tip of the trowel was clearly difficult to move was evaluated as x.

[Creativity]
A 900 mm square flexible board conforming to JISA 5430 is installed vertically, and when creating a coating film of an example or a comparative example, the coating thickness is 2 to 5 mm while applying a water-based coating composition with a trowel tip to make a difference in unevenness. Attach a fan-shaped handle so that it will be like this, and dry it as it is. After curing, it was evaluated as ◯ when the applied pattern remained as it was, Δ when there was some deterioration (sagging, leveling) in the pattern, and × when there was obvious deterioration.

[Thermal insulation properties]
Using a 300 mm square JISA5430 standard flexible board as a substrate, each coating film of Examples or Comparative Examples is prepared and cured at 23° C. and 50% RH for 14 days to obtain a test specimen. The specimen is held horizontally, a projector NT-200 (200 watts, manufactured by Nichido Kogyo Co., Ltd.) is installed 25 cm above the center, the light of the projector is applied to the coating film surface, and the coating after 30 minutes The film surface temperature and the coating film back surface temperature (the coating film surface in contact with the flexible board) are measured, and if the difference between the coating film surface temperature and the coating film back surface temperature is 15 ° C or more, it is evaluated as having heat insulation. A temperature of less than 15°C was evaluated as having no heat insulating properties.

[Zero span tensile properties (butt joint)]
A flexible board (100×100 mm, 10 mm thick) stipulated in JISA5430 is used as the substrate, and the edges of the two substrates are pressed against each other, and the back surface is temporarily fixed with a curing tape. 0.2 kg/m ² of a solvent chloride rubber undercoat material (JS-410, manufactured by Aica Kogyo Co., Ltd., trade name) is applied as a sealer to the front surface of the base, and dried for 4 hours or more. A coating film of the example was prepared and cured for 14 days at a temperature of 23° C. and a humidity of 50% RH to obtain a test specimen. After that, remove the temporary fixing curing tape on the back side, pull both ends of the test piece at 2 mm / min with an Instron universal tester, and the distance at which the pinhole occurs at the thrust part is 1.8 mm or more ○, 1.8 mm Less than was evaluated as x.

[Zero span tensile properties (10 mm joint)]
A flexible board (100 x 100 mm, thickness 10 mm) specified in JISA 5430 was used as the base, and the ends of the two bases were opened by 10 mm to form a joint, and the joint was filled with a one-component polyurethane sealant and cured at 23 ° C for 7 days. , as a base for coating in Examples or Comparative Examples. 0.2 kg/m ² of a solvent chloride rubber undercoat material (JS-410, manufactured by Aica Kogyo Co., Ltd., trade name) is applied as a sealer to the front surface of the base to be applied, dried for 4 hours or more, and then applied. A coating film of an example or a comparative example was prepared and cured for 14 days at a temperature of 23° C. and a humidity of 50% RH to obtain a test specimen. After that, both ends of the specimen were pulled at 2 mm/min using an Instron universal testing machine.

[Fatigue resistance (expansion after tension)]
A flexible board (200 x 150 mm, thickness 8 mm) specified by JISA 5430 is used as the base, and the ends of the 150 mm portions of the two bases are opened by 10 mm to form a joint. It is cured for a day and used as a coating base for Examples or Comparative Examples. 0.2 kg/m ² of a solvent chloride rubber undercoat material (JS-410, manufactured by Aica Kogyo Co., Ltd., trade name) is applied as a sealer to the front surface of the base to be applied, dried for 4 hours or more, and then applied. A coating film of an example or a comparative example was prepared and cured for 14 days at a temperature of 23° C. and a humidity of 50% RH to obtain a test specimen.

The test method conformed to JISA 1436 "Test method for fatigue resistance in discontinuous part of substrate of architectural film material 5. Test method", and the specimen was pulled in the longitudinal direction by 0.1 mm to set the starting point of the movement. Next, it is stretched 500 times at 20° C., then 500 times at 60° C., and then 500 times at -20° C., by pulling 0.1 mm further from the starting point and returning to the starting point. When no abnormality is observed, the stretching is repeated 500 times each at 20°C, 60°C and -20°C by pulling 0.2 mm from the starting point and returning to the starting point. These were repeated in order, and if there were no abnormalities, the test was continuously performed by adding 0.1 mm to the pulling distance from the starting point and repeating the expansion and contraction, and the tensile length from the starting point was 0.5 mm at each temperature. A case where there was no abnormality in the coating film after expansion and contraction was evaluated as ◯.

[Fatigue resistance (stretch after compression)]
The test specimen is the same as the test specimen for [Fatigue resistance (expansion after tension)], and the test method is also based on JISA 1436 “Fatigue resistance test method for discontinuous base of architectural coating material 5. Test method”. Then, the test body was compressed by 0.1 mm in the longitudinal direction to be the starting point of the movement. Next, the expansion and contraction of pulling 0.1 mm from the starting point and returning to the starting point is performed 500 times at 20°C, then 500 times at 60°C, and then 500 times at -20°C. If no is observed, the stretching is repeated 500 times each at 20°C, 60°C and -20°C by pulling 0.2 mm further from the starting point and returning to the starting point. These were repeated sequentially, and if there were no abnormalities, the test was continued in which the stretching distance from the starting point was increased by 0.1 mm in sequence and the stretching was repeated. Those with no abnormalities in the coating film afterward were evaluated as ◯.

[Evaluation results]

Table 2 shows the evaluation results.

Claims (6)

A composition comprising an acrylic resin emulsion, a filler, an aggregate, a pigment, a thickener, a film forming aid, an inorganic hollow filler, vinylon fibers having a length of 2 to 7 mm, and water. With respect to 100 parts by weight of the whole product, the inorganic hollow filler is 20 to 30 parts by weight, the vinylon fiber is 0.2 to 0.4 parts by weight, and the resin solid content in the acrylic resin emulsion is 5 to 20 parts by weight. A water-based coating material composition characterized in that it can be applied in a coating thickness of 2 to 5 mm to impart a design with an uneven pattern. 2. A water-based coating material composition according to claim 1, wherein said inorganic hollow filler comprises a spherical foam of volcanic fine-grained vitreous tuff and a glass foam. The inorganic hollow filler is characterized by comprising a spherical foam of volcanic fine-grain vitreous tuff with an average particle size of 200 to 400 μm and a glass foam with an average particle size of 1.0 to 1.4 mm. The water-based coating material composition according to claim 1 or 2. A plurality of exterior wall materials are attached to a substrate with their side ends butted against each other, and the water-based coating material composition according to any one of claims 1 to 3 is applied to the surfaces of the butted portions of the side ends. A jointless finishing method for an outer wall to make a jointless finish, in which a sealer is applied to the surface of the butted part if necessary, and then the water-based coating material composition according to any one of claims 1 to 3 is applied with a coating thickness of 2 to 5 mm to adjust the unevenness of the butted part, and then the water-based coating material composition according to any one of claims 1 to 3 is applied with a coating thickness of 2 to 5 mm. A jointless finishing method for an outer wall characterized by finishing by attaching. 5. The jointless finishing method for an outer wall according to claim 4, further comprising applying a sand wall-like paint composition. 6. The jointless finishing method for an outer wall according to claim 5, wherein the sand wall-like paint composition has heat shielding properties.