JP7699353B2 - building materials - Google Patents

Description

This disclosure relates to building materials.

One method of making wood flame retardant is to impregnate the wood with a flame retardant. The method of impregnating wood with a flame retardant is disclosed in Patent Document 1. One method of making plastic flame retardant is to change the composition of the plastic. The method of changing the composition of the plastic is disclosed in Patent Document 2.

JP 2019-137805 A JP 2000-273298 A

Special equipment is required to allow the flame retardant to penetrate wood. In addition, it takes a lot of time and energy to allow the flame retardant to penetrate wood. When changing the composition of the plastic, the composition of the plastic is limited.

It is conceivable that a coating composition can be applied to a flammable substrate such as wood or plastic to form a coating layer, which can make the flammable substrate flame-retardant. When heated, the coating layer foams and becomes a heat insulating layer.
When the building material is used on a ceiling surface, for example, if the coating layer foams excessively, the heat insulating layer may fall off and the flame retardancy may decrease. In one aspect of the present disclosure, it is preferable to provide a building material that has flame retardancy and can suppress the coating layer from foaming excessively.

One aspect of the present disclosure is a building material comprising a substrate and a coating layer formed on the surface of the substrate. The coating layer comprises a coating film that foams when heated, and a glass fiber portion made of glass fiber cloth or glass fiber nonwoven fabric, at least a portion of which is embedded in the coating film.

The building material, which is one aspect of the present disclosure, has an effect of suppressing excessive foaming of the coating layer (hereinafter referred to as the foaming suppression effect) by including a glass fiber portion. In addition, since the coating layer includes a coating film that foams when heated, the building material, which is one aspect of the present disclosure, has high flame retardancy.

FIG. 2 is a cross-sectional view showing the configuration of a building material. FIG. 2 is a cross-sectional view showing the configuration of a building material. FIG. 1 is an explanatory diagram showing a manufacturing method of a building material.

Exemplary embodiments of the present disclosure will now be described with reference to the drawings.
1. Structure of the building material (1) Substrate The building material includes a substrate. An example of the substrate is a flammable substrate. An example of the flammable substrate is wood. An example of the wood is cedar lumber having a thickness of 12 mm, a width of 100 mm, and a length of 2000 mm.

The substrate is not limited to wood and can be selected arbitrarily. Examples of substrates include plastics, wooden building materials, paper, and cloth. Examples of plastics include polyethylene resin, polypropylene resin, acrylic resin, phenolic resin, polyvinyl chloride resin, and expanded polystyrene resin. Examples of wooden building materials include lumber, laminated lumber, plywood, laminated veneer lumber (LVL), cross-laminated timber (CLT), and medium-density fiberboard (MDF). The form of the substrate is not particularly limited. Examples of the form of the substrate include columnar, board, sheet, and cloth.

The substrate may be, for example, a wooden structural member, such as a pillar, a beam, a wall, or a floor.
The pillar may be, for example, a rectangular pillar. The cross-sectional shape of the rectangular pillar in a cross section perpendicular to the longitudinal direction is, for example, a square. The length of one side of the square is, for example, 90 mm or more and 1100 mm or less.

An example of a beam is a rectangular beam. The cross-sectional shape of a rectangular beam in a cross section perpendicular to the longitudinal direction is, for example, a rectangle. The length of one side of the rectangle is, for example, 90 mm or more and 800 mm or less. The length of the side adjacent to the one side is, for example, 90 mm or more and 1200 mm or less. The length of a rectangular beam is not particularly limited, but is, for example, 3000 mm or more and 10000 mm or less.

The shape of the wall is, for example, a rectangle. The length of the short side of the rectangle is, for example, 3000 mm or less. The length of the short side of the rectangle is, for example, 500 mm or more. The length of the long side of the rectangle is, for example, 12000 mm or less. The length of the long side of the rectangle is, for example, 2000 mm or more.

The substrate may be, for example, a piece of wood with a plate- or sheet-like member attached to its surface. Examples of the plate- or sheet-like member include gypsum board, fireproof sheet, decorative material, and the like.
(2) Configuration of the coating layer The building material includes a coating layer. The coating layer is formed on the surface of the substrate. The coating layer includes a coating film and a glass fiber portion. The coating film foams when heated. The glass fiber portion is made of glass fiber cloth or glass fiber nonwoven fabric. At least a portion of the glass fiber portion is embedded in the coating film.

For example, as shown in FIG. 1, the building material 1 includes a substrate 3 and a coating layer 5. The coating layer 5 is formed on the surface of the substrate 3. The coating layer 5 includes a coating film 7 and a glass fiber portion 9. In the embodiment shown in FIG. 1, the entire glass fiber portion 9 is embedded in the coating film 7. The coating film 7 is impregnated into the interior of the glass fiber portion 9.

In the thickness direction, the glass fiber part 9 is preferably located closer to the surface 5B of the coating layer 5 than to the center 5A in the thickness direction of the coating layer 5. When the glass fiber part 9 is located closer to the surface 5B than to the center 5A, the foaming suppression effect is even higher.

It is preferable that the coating layer 5 has a portion on the substrate 3 side that does not contain the glass fiber portion 9 (hereinafter referred to as the non-containing portion 5C). The non-containing portion 5C is, for example, composed only of the coating film 7. When the coating layer 5 has the non-containing portion 5C, the foaming suppression effect is even higher.

For example, as shown in FIG. 2, the building material 1 comprises a substrate 3 and a coating layer 5. The coating layer 5 is formed on the surface of the substrate 3. The coating layer 5 comprises a coating film 7 and a glass fiber portion 9. In the embodiment shown in FIG. 2, the surface 9A of the glass fiber portion 9 coincides with the surface 5B of the coating layer 5. The coating film 7 is impregnated into the glass fiber portion 9. The coating layer 5 preferably has a non-containing portion 5C on the substrate 3 side. When the coating layer 5 has a non-containing portion 5C, the foaming suppression effect is even higher.

Examples of glass constituting the glass fiber cloth or glass fiber nonwoven fabric include alumina borosilicate glass, soda lime glass, and quartz glass. Alumina borosilicate glass has a low thermal expansion coefficient and is resistant to thermal shock, making it preferable as the glass constituting the glass fiber cloth or glass fiber nonwoven fabric. It is preferable that 97 mass% or more of the glass constituting the glass fiber cloth or glass fiber nonwoven fabric is alumina borosilicate glass.

Examples of sizing agents contained in the glass fiber cloth or glass fiber nonwoven fabric include starch, acrylic resin, PVA, EVA, etc. The content of the sizing agent in the glass fiber cloth or glass fiber nonwoven fabric is preferably 3 mass% or less.

The weaving density in the longitudinal direction of the glass fiber cloth is preferably 30 threads/25 mm or more and 70 threads/25 mm or less, and more preferably 53 threads/25 mm. The weaving density in the transverse direction of the glass fiber cloth is preferably 30 threads/25 mm or more and 70 threads/25 mm or less, and more preferably 48 threads/25 mm.

When the weaving density in the vertical or horizontal direction is 70 threads/25 mm or less, the paint composition penetrates better into the glass fiber cloth. When the weaving density in the vertical or horizontal direction is 30 threads/25 mm or more, the foaming inhibition effect is even higher.

The glass fiber cloth is preferably woven in a plain weave. The mass per unit area of the glass fiber cloth or the glass fiber nonwoven fabric is preferably 70 g/ ^m2 or more and 150 g/ ^m2 or less, and more preferably 92 g/ ^m2 .

The thickness of the glass fiber cloth or the glass fiber nonwoven fabric is preferably 0.05 mm or more and 0.20 mm or less, and more preferably 0.09 mm or more and 0.1 mm or less.
The tensile strength of the glass fiber cloth or the glass fiber nonwoven fabric in the longitudinal direction is preferably 300 N/25 mm or more and 1000 N/25 mm or less, more preferably 510 N/25 mm. The tensile strength of the glass fiber cloth or the glass fiber nonwoven fabric in the transverse direction is preferably 300 N/25 mm or more and 1000 N/25 mm or less, more preferably 451 N/25 mm.

The mass per unit area of the coating film 7 is from 250 g/ ^m2 to 550 g/ ^m2 , and the mass per unit area of the portion of the coating film 7 that is impregnated in the glass fiber part 9 or that is closer to the surface 5B than the glass fiber part 9 is preferably from 75 g/ ^m2 to 275 g/ ^m2 . In this case, the foaming suppression effect is further enhanced.

(3) Structure of the coating composition The coating film is formed by applying a coating composition. Examples of the coating composition include a coating composition (hereinafter referred to as a specific coating composition) containing (a) a water-soluble melamine resin, (b) a condensation-polymerized phosphate ester, and (c) one or more of phosphoric acid, boric acid, ammonium salt, and ammonia water. The specific coating composition may further contain one or more of (d) a compound having an amino group in the molecular structure, (e) kaolin, and (f) glass fiber.

The coating composition used to form the coating film may be any other coating composition as long as it can form a coating film that foams when heated. It is preferable that the coating film formed by applying the other coating composition has transparency.

(3-1) (a) Water-soluble melamine resin The specific coating composition contains a water-soluble melamine resin. The water-soluble melamine resin can be produced, for example, by reacting an aldehyde with melamine in the presence of an alkali catalyst. Methods for producing water-soluble melamine resin are disclosed, for example, in Japanese Patent No. 257115, Japanese Patent Laid-Open No. 51-114492, and Japanese Patent Laid-Open No. 2006-124457.

Examples of water-soluble melamine resins include methylol melamine resins and alkoxylated methylol melamine resins. Examples of methylol melamine resins include monomethylol melamine resins, dimethylol melamine resins, and trimethylol melamine resins. Examples of alkoxylated methylol melamine resins include methylol melamine resins, methylated methylol melamine resins, methoxymethylol melamine resins, and butylated methylol melamine resins.

The alkoxylated methylol melamine resin may be completely alkoxylated, may have a residual methylol group, or may have a residual imino group. The specific coating composition may also contain a copolymer of a water-soluble melamine resin and a phenolic resin or the like. Of the water-soluble melamine resins, methylol melamine resins are more preferred.

When the specific coating composition contains methylol melamine resin, the flame retardancy of the substrate and the transparency of the coating film become even more pronounced. In this specification, transparency is not limited to complete transparency, and may be, for example, semi-transparent.

(3-2) (b) Polycondensation Phosphate The specific coating composition contains a polycondensation phosphate. The polycondensation phosphate is an ester obtained by a condensation reaction between polyphosphoric acid and an alcohol. Examples of the alcohol include aliphatic alcohols, glycols, polyhydric alcohols, and glycerin.

Examples of aliphatic alcohols include methanol, ethanol, butanol, and propanol. Examples of glycols include ethylene glycol and propylene glycol. Examples of polyhydric alcohols include pentaerythritol, dipentaerythritol, and tripentaerythritol.

As the condensation polymerization phosphate ester, a condensation polymerization phosphate ester obtained using a polyhydric alcohol is preferred. When the specific paint composition contains a condensation polymerization phosphate ester obtained using a polyhydric alcohol, the flame retardancy of the substrate and the transparency of the coating film become even more pronounced. As the condensation polymerization phosphate ester, a condensation polymerization phosphate ester obtained using pentaerythritol is even more preferred. When the specific paint composition contains a condensation polymerization phosphate ester obtained using pentaerythritol, the flame retardancy of the substrate and the transparency of the coating film become even more pronounced.

The blending ratio of the condensation polymerization phosphate ester to 100 parts by mass of the water-soluble melamine resin is preferably 120 parts by mass or more and 350 parts by mass or less, more preferably 130 parts by mass or more and 200 parts by mass or less, and most preferably 170 parts by mass.

When the blending ratio of the condensation polymerization phosphate ester to 100 parts by mass of the water-soluble melamine resin is 120 parts by mass or more and 350 parts by mass or less, the flame retardancy of the substrate and the transparency of the coating film become more pronounced. When an excess of the condensation polymerization phosphate ester is mixed with the water-soluble melamine resin, the flame retardancy of the substrate and the transparency of the coating film become more pronounced.

(3-3) Component (c) The specific coating composition contains component (c). Component (c) contains one or more of phosphoric acid, boric acid, ammonium salt, and ammonia water. Component (c) contains, for example, both phosphoric acid and boric acid. Examples of ammonium salts include ammonium phosphate salts and ammonium borate salts.

Ammonia gradually evaporates from the ammonium salt and ammonia water. The evaporating ammonia retards the hardening of the water-soluble melamine resin.
The blending ratio of component (c) per 100 parts by mass of the water-soluble melamine resin is preferably 15 parts by mass or more and 90 parts by mass or less, more preferably 20 parts by mass or more and 50 parts by mass or less, and most preferably 31 parts by mass.

When the blending ratio of component (c) to 100 parts by mass of the water-soluble melamine resin is 15 parts by mass or more and 90 parts by mass or less, the flame retardancy of the substrate and the transparency of the coating film become more pronounced. When component (c) contains an excess of phosphoric acid or boric acid relative to the water-soluble melamine resin, the curing of the water-soluble melamine resin is accelerated.

Furthermore, when component (c) contains excess phosphoric acid or boric acid relative to the water-soluble melamine resin, the excess phosphoric acid or boric acid chemically bonds with the hydroxyl groups of the substrate, improving adhesion between the coating and the substrate. When the substrate is wood, the phosphoric acid or boric acid chemically bonds with the hydroxyl groups of cellulose. Furthermore, the excess phosphoric acid or boric acid chemically bonds with the water-soluble melamine resin decomposed by the heat of combustion during a fire, further enhancing the flame retardancy of the substrate. It is presumed that the excess phosphoric acid or boric acid chemically bonds with the hydroxyl groups produced by the thermal decomposition of the water-soluble melamine resin.

(3-4) (d) Compound Having an Amino Group in the Molecular Structure The specific coating composition contains (d) a compound having an amino group in the molecular structure (hereinafter also referred to as component (d)). When the specific coating composition contains component (d), the specific coating composition cures faster at room temperature. When the specific coating composition cures faster at room temperature, sagging is reduced when the specific coating composition is applied to a vertical surface.

Examples of the component (d) include urea, melamine, aliphatic amines, aromatic amines, and heterocyclic amines.
Examples of aliphatic amines include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, triethanolamine, N,N-diisopropylethylamine, tetramethylethylenediamine, hexamethylenediamine, spermidine, spermine, and amantadine.

Examples of aromatic amines include aniline, phenethylamine, toluidine, catecholamine, and 1,8-bis(dimethylamino)naphthalene.
Examples of heterocyclic amines include pyrrolidine, piperidine, piperazine, morpholine, quinuclidine, 1,4-diazabicyclo[2.2.2]octane, pyrrole, pyrazole, imidazole, pyridine, pyridazine, pyrimidine, pyrazine, oxazole, thiazole, and 4-dimethylaminopyridine.

As the (d) component, those having two or more amino groups or urea are preferred. Examples of the (d) component having two or more amino groups include ethylenediamine, hexamethylenediamine, etc.

When the specific coating composition contains, as component (d), a compound having two or more amino groups or urea, the curing of the specific coating composition at room temperature becomes faster.
The reason why the specific coating composition cures more quickly at room temperature is presumed to be because the polycondensation product of component (d) and formaldehyde remaining in the water-soluble melamine resin reduces the fluidity of the specific coating composition. The polycondensation product of component (d) and formaldehyde is component (D) described below.

The blending ratio of component (d) to 100 parts by mass of water-soluble melamine resin is preferably 0.05 parts by mass or more and 5 parts by mass or less, more preferably 0.5 parts by mass or more and 5 parts by mass or less, and particularly preferably 2.5 parts by mass. When the blending ratio of component (d) to 100 parts by mass of water-soluble melamine resin is 0.05 parts by mass or more and 5 parts by mass or less, the hardening of the specific coating composition at room temperature becomes even faster.

(3-5) (e) Kaolin The specific coating composition further contains, for example, (e) kaolin. As the kaolin, halloysite (Al ₂ Si ₂ O ₅ (OH) 4.2H ₂ O) is preferable. Halloysite has _a tubular crystal structure. Halloysite has siloxane (-Si-O-Si-) on the outside and aluminol (-Al-O-Al-) on the inside. Therefore, the surface of halloysite is acidic.

When the specific coating composition contains kaolin, the specific coating composition hardens faster. When the specific coating composition contains halloysite, the specific coating composition hardens even faster.
The particle size of the kaolin is preferably 1 μm or more and 10 μm or less. When the particle size of the kaolin is 1 μm or more and 10 μm or less, the hardening of the specific coating composition becomes faster.

The mixing ratio of kaolin to 100 parts by mass of water-soluble melamine resin is preferably 20 parts by mass or more and 250 parts by mass or less, more preferably 50 parts by mass or more and 200 parts by mass or less, and most preferably 150 parts by mass or more and 180 parts by mass or less. When the mixing ratio of kaolin to 100 parts by mass of water-soluble melamine resin is 250 parts by mass or less, it is possible to prevent the coating film from becoming cloudy.

(3-6) (f) Glass Fiber The specific coating composition further contains, for example, (f) glass fiber. The form of the glass fiber is, for example, powder. When the specific coating composition contains glass fiber, the shape retention of the heat insulating layer after heat foaming is improved. The diameter of the glass fiber is preferably 5 μm or more and 20 μm or less, and more preferably 10 μm. The length of the glass fiber is preferably 10 μm or more and 300 μm or less, and more preferably 30 μm or more and 50 μm or less. The value obtained by dividing the length of the glass fiber by the diameter of the glass fiber is defined as the aspect ratio of the glass fiber. The aspect ratio of the glass fiber is preferably 1.5 or more and 5.5 or less.

Glass fiber is sometimes called powder or milled. Glass fiber that has not been surface-treated is preferred. Commercially available glass fiber products include milled fiber (Central Glass Fiber Co., Ltd.), milled fiber (Asahi Fiberglass Co., Ltd.), PF cut fiber (Nitto Boseki Co., Ltd.), milled fiber (Nippon Electric Glass Co., Ltd.), etc.

(3-7) Other Components The specific coating composition may contain additives, pigments, etc. used in ordinary coatings, to the extent that the flame retardancy, transparency of the coating film, and curing speed of the coating film are not significantly impaired. Examples of additives include thickeners, pH adjusters, dispersants, wetting agents, preservatives, dyes, etc., defoamers, pigments, etc.

Examples of thickeners include polyvinyl alcohol, urethane-modified polyether, carboxymethyl cellulose, etc. Examples of pH adjusters include ammonia water, amines, etc. Examples of pigments include inorganic pigments, organic pigments, and extender pigments, etc. Examples of inorganic pigments include carbon black, titanium oxide, and iron oxide, etc. Examples of organic pigments include quinacridone and azo pigments, etc. Examples of extender contents include silica, barium sulfate, talc, and mica, etc.

The specific coating composition contains, for example, an acid. The acid promotes the curing of the water-soluble melamine resin. Examples of the acid include sulfonic acid and carboxylic acid. Examples of the sulfonic acid include p-toluenesulfonic acid. Examples of the carboxylic acid include acetic acid, citric acid, maleic acid, and acrylic acid.

The specific coating composition contains, for example, components of an intumescent fireproof coating to the extent that the transparency of the coating film is not significantly impaired. Examples of components of an intumescent fireproof coating include ammonium polyphosphate, melamine, polyhydric alcohols, etc. Examples of polyhydric alcohols include pentaerythritol, etc.

(3-8) Form of specific coating composition The specific coating composition is, for example, in the form of a two-liquid composition composed of a first agent and a second agent. The first agent contains a water-soluble melamine resin. The second agent contains a condensation polymerization phosphate ester and component (c). The first agent and the second agent are mixed before use. When the specific coating composition is in the form of a two-liquid composition, the storage stability of the specific coating composition is high.

It is preferable that the (d) component is contained in the second agent and not in the first agent. When the (d) component is contained in the second agent and not in the first agent, the storage stability of the specific coating composition is higher.
(4) Coating The coating contains, for example, (A) a water-soluble melamine resin, (B) a condensation-polymerized phosphate ester, and (C) one or more of phosphoric acid, boric acid, an ammonium salt, and ammonia. The coating further contains, for example, one or more of (D) a polycondensate of a compound having an amino group in its molecular structure and formaldehyde, (E) kaolin, and (F) glass fiber.

(A) Water-soluble melamine resin is, for example, the same as (a) water-soluble melamine resin contained in the specific paint composition. (B) Polycondensation phosphate ester is, for example, the same as (b) polycondensation phosphate ester contained in the specific paint composition.

In the coating film, the blending ratio of the condensation polymerization phosphate ester to 100 parts by mass of the water-soluble melamine resin is preferably 120 parts by mass or more and 350 parts by mass or less, more preferably 130 parts by mass or more and 200 parts by mass or less, and most preferably 170 parts by mass.

When the mixing ratio of the condensation polymerization phosphate ester to 100 parts by mass of the water-soluble melamine resin in the coating film is 120 parts by mass or more and 350 parts by mass or less, the flame retardancy of the building material and the transparency of the coating film become more pronounced. When an excess of the condensation polymerization phosphate ester is mixed with the water-soluble melamine resin, the flame retardancy of the building material and the transparency of the coating film become more pronounced.

Component (C) is essentially the same as component (c) contained in the specific coating composition, except that one option for component (C) is ammonia rather than aqueous ammonia.
In the coating film, the blending ratio of component (C) per 100 parts by mass of the water-soluble melamine resin is preferably 15 parts by mass or more and 90 parts by mass or less, more preferably 20 parts by mass or more and 50 parts by mass or less, and most preferably 31 parts by mass.

When the mixing ratio of component (C) to 100 parts by mass of water-soluble melamine resin in the coating film is 15 parts by mass or more and 90 parts by mass or less, the flame retardancy of the building material and the transparency of the coating film become more pronounced. When component (C) contains an excess of phosphoric acid or boric acid relative to the water-soluble melamine resin, the hardening of the water-soluble melamine resin is accelerated.

Furthermore, when component (C) contains excess phosphoric acid or boric acid relative to the water-soluble melamine resin, the excess phosphoric acid or boric acid chemically bonds with the hydroxyl groups of the substrate, improving adhesion between the coating and the substrate. When the substrate is wood, the phosphoric acid or boric acid chemically bonds with the hydroxyl groups of cellulose. Furthermore, the excess phosphoric acid or boric acid chemically bonds with the water-soluble melamine resin decomposed by the heat of combustion during a fire, further enhancing the flame retardancy of the building material. It is presumed that the excess phosphoric acid or boric acid chemically bonds with the hydroxyl groups produced by the thermal decomposition of the water-soluble melamine resin.

The compound having an amino group in its molecular structure in component (D) is, for example, the same as component (d) contained in the specific coating composition.
In the coating film, the blending ratio of the (D) component to 100 parts by mass of the water-soluble melamine resin is preferably 0.05 parts by mass or more and 5 parts by mass or less, more preferably 0.5 parts by mass or more and 5 parts by mass or less. When the blending ratio of the (D) component to 100 parts by mass of the water-soluble melamine resin is 0.05 parts by mass or more and 5 parts by mass or less, the coating film hardens more quickly at room temperature when the building material is produced.

The coating film contains, for example, (E) kaolin. (E) Kaolin is, for example, the same as the component (e) contained in the specific coating composition.
In the coating film, the blending ratio of kaolin to 100 parts by mass of the water-soluble melamine resin is preferably 20 parts by mass or more and 250 parts by mass or less, more preferably 50 parts by mass or more and 200 parts by mass or less, and most preferably 150 parts by mass or more and 180 parts by mass or less. When the blending ratio of kaolin to 100 parts by mass of the water-soluble melamine resin is 250 parts by mass or less, it is possible to prevent the coating film from becoming cloudy.

The coating film contains, for example, (F) glass fiber. (F) Glass fiber is, for example, the same as component (f) contained in the specific coating composition. The coating film may contain, for example, "other components" in the specific coating composition.

The coating film may be a coating film formed by applying a coating composition other than the specific coating composition, so long as it has the effect of foaming when heated. It is preferable that the coating film has transparency.
2. Manufacturing method of building material The building material can be manufactured, for example, by the method shown in Fig. 3. As shown in S1 of Fig. 3, a coating composition is applied to the surface of the substrate 3 to form a first coating film 11. The coating composition is, for example, a specific coating composition. Next, the first coating film 11 is left to stand until it hardens and loses fluidity. The standing time is, for example, several hours to several weeks. Next, as shown in S2, a glass fiber part 9 is placed on the first coating film 11.

Next, as shown in S3, a coating composition is applied onto the glass fiber portion 9 to form a second coating film 13. The coating composition applied in S3 is, for example, the same type of coating composition as the coating composition applied in S1. At least a portion of the coating composition applied in S3 soaks into the glass fiber portion 9.

Next, the second coating film 13 is cured. The above steps complete the building material 1. The first coating film 11 and the second coating film 13 become the coating film 7 that constitutes the coating layer 5. The first coating film 11 becomes the non-containing portion 5C. When a sufficient amount of coating composition is applied in S3, the entire glass fiber portion 9 is embedded in the coating film 7, as shown in FIG. 1. When a small amount of coating composition is applied in S3, the surface 9A of the glass fiber portion 9 and the surface 5B of the coating layer 5 coincide with each other, as shown in FIG. 2. The second coating film 13 is the portion of the coating film 7 that is impregnated in the glass fiber portion 9 or is located closer to the surface 5B than the glass fiber portion 9.

3. Effects of the Building Material (3-1) When a fire breaks out around the building material 1 and the coating layer 5 is heated, the coating film 7 contained in the coating layer 5 foams. As a result, the coating layer 5 forms a heat insulating layer. The formed heat insulating layer suppresses the combustion of the substrate 3. The coating layer 5 contains the glass fiber part 9, and thus has a foaming suppression effect.

(3-2) The coating film 7 is, for example, a coating film formed by applying a specific coating composition. In this case, the building material 1 can further suppress the combustion of the substrate 3.
(3-3) The mass per unit area of the coating film 7 is, for example, 250 g/m2 or ^more and 550 g/ ^m2 or less, and the mass per unit area of the portion of the coating film 7 that is impregnated in the glass fiber part 9 or that is closer to the surface 5B than the glass fiber part 9 is, for example, 75 g/ ^m2 or more and 275 g/ ^m2 or less. In this case, the foaming suppression effect of the building material 1 is even higher.

(3-4) The coating layer 5 includes, for example, a non-containing portion 5C. In this case, the foaming suppression effect of the building material 1 is further enhanced.
4. Examples (4-1) Production of specific coating composition The following components were mixed to produce the first and second parts of the specific coating composition.
<First Agent>
Water-soluble melamine resin: 20 parts by weight Glass fiber: 50 parts by weight Kaolin: 1.5 parts by weight Wetting agent: 0.5 parts by weight <Second agent>
Polycondensation phosphate ester: 30 parts by mass Phosphoric acid: 5 parts by mass Urea: 0.5 parts by mass The first and second agents each contained water as a solvent. In each of the first and second agents, the mass ratio of the non-volatile content to the total mass was 76 mass%. The diameter of the glass fiber contained in the first agent was 10 μm, and the fiber length was 30 to 50 μm.

(4-2) Manufacturing of building material 1
(i) Example 1
A rectangular plate-shaped laminated wood was prepared as the substrate 3. The dimensions of the substrate 3 were 99 mm long, 99 mm wide, and 30 mm thick. As shown in S1 of FIG. 3, the specific coating composition produced in (4-1) above was applied to the surface of the substrate 3 to form a first coating film 11. The specific coating composition was a mixture of 100 parts by mass of the first agent and 100 parts by mass of the second agent.

Next, the first coating film 11 was left to stand for 16 hours until it cured and lost fluidity. The mass per unit area of the first coating film 11 was 183 g/ ^m2 . The mass per unit area of the first coating film 11 is the mass per unit area of the non-volatile components.

Next, as shown in S2 of FIG. 3, a glass fiber portion 9 made of glass fiber cloth was placed on the first coating film 11. At least 97% by mass of the glass constituting the glass fiber cloth was alumina borosilicate glass. The sizing agent contained in the glass fiber cloth was an acrylic resin. The content of the sizing agent in the glass fiber cloth was 13% by mass. The content of glass in the glass fiber cloth was 87% by mass.

The weaving density in the longitudinal direction of the glass fiber cloth was 53 threads/25 mm. The weaving density in the transverse direction of the glass fiber cloth was 48 threads/25 mm. The weaving method of the glass fiber cloth was plain weave. The mass per unit area of the glass fiber cloth was 150 g/ ^m2 . The thickness of the glass fiber cloth was 0.1 mm.

Next, as shown in S3 of Fig. 3, the specific coating composition was applied onto the glass fiber portion 9 to form a second coating film 13. Next, the second coating film 13 was cured. The mass per unit area of the second coating film 13 was 197 g/ ^m2 . The mass per unit area of the second coating film 13 is the mass per unit area of the non-volatile components.

The above steps completed the construction material 1 of Example 1. The first coating film 11 and the second coating film 13 became the coating film 7 that constitutes the coating layer 5. The first coating film 11 became the non-containing portion 5C. As shown in FIG. 1, the entire glass fiber portion 9 was embedded in the coating film 7. The second coating film 13 became the portion of the coating film 7 that either impregnated the glass fiber portion 9 or was located closer to the surface 5B than the glass fiber portion 9.

(ii) Examples 2 to 7
Building materials 1 of Examples 2 to 7 were produced basically in the same manner as in Example 1. However, the mass per unit area of the first coating film 11 and the mass per unit area of the second coating film 13 were as shown in Table 1.

In Example 4, a glass fiber part 9 made of a glass fiber nonwoven fabric was used instead of the glass fiber part 9 made of a glass fiber cloth. Of the glass constituting the glass fiber nonwoven fabric, 97% by mass or more was alumina borosilicate glass. The sizing agent contained in the glass fiber nonwoven fabric was an acrylic resin. The content of the sizing agent in the glass fiber nonwoven fabric was 13% by mass. The content of glass in the glass fiber nonwoven fabric was 87% by mass. The mass per unit area of the glass fiber nonwoven fabric was 150 g/ ^m2 . The thickness of the glass fiber nonwoven fabric was 0.1 mm.

In Examples 5 and 6, the amount of the specific coating composition applied in S3 was small, so that the surface 9A of the glass fiber portion 9 and the surface 5B of the coating layer 5 were flush with each other, as shown in FIG.
(iii) Comparative Examples 1 and 2
The building materials 1 of Comparative Examples 1 and 2 were manufactured basically in the same manner as in Example 1. However, in Comparative Example 1, after the first coating film 11 was formed and cured, the second coating film 13 was formed without placing the glass fiber part 9. Therefore, in Comparative Example 1, the coating layer 5 does not include the glass fiber part 9.

In Comparative Example 2, the first coating film 11 and the second coating film 13 were formed in the same manner as in Comparative Example 1, and then the glass fiber part 9 made of glass fiber cloth was placed on the second coating film 13. Therefore, in Comparative Example 2, the glass fiber part 9 was not embedded in the coating film 7.

The mass per unit area of the first coating film 11 and the mass per unit area of the second coating film 13 in Comparative Examples 1 and 2 were as shown in Table 1.
(4-3) Evaluation of Building Material 1 Tests were conducted on the building material 1 of each example and each comparative example. The total heat generation amount and maximum heat generation rate were measured when the test specimen was heated for 10 minutes at a radiation intensity of 50 kW/ ^m2 using the cone calorimeter method specified in ISO 5660-1. The measured values were applied to the following evaluation criteria to evaluate the flame retardancy. The evaluation results are shown in Table 1.

(Evaluation criteria for flame retardancy based on total heat generation)
◯: 7.2 MJ/m2 or ^less △: 8 MJ/m2 or ^less ×: More than 8 MJ/ ^m2 (Evaluation criteria for flame retardancy based on maximum heat generation rate)
◯: 180 kW/m2 or ^less △: 200 kW/m2 or ^less ×: More than 200 kW/ ^m2 When the cone calorimeter method is performed, an igniter is placed above the test specimen. When the coating layer 5 foamed, it was observed whether the coating layer 5 came into contact with the igniter. Based on the observation results, the foaming suppression effect was evaluated according to the following criteria. The evaluation results are shown in Table 1. If the coating layer 5 foams excessively, the coating layer 5 is likely to come into contact with the igniter.

(Evaluation Criteria for Foam Inhibition Effect)
◯: The coating layer 5 does not come into contact with the igniter.
Δ: The coating layer 5 comes into contact with the igniter, but the contact time is within 10 seconds.

x: The coating layer 5 comes into contact with the igniter, and the contact time exceeds 10 seconds.
The building material 1 was also visually observed, and the transparency of the coating layer 5 was evaluated according to the following criteria. The evaluation results are shown in Table 1.

(Transparency evaluation criteria)
◯: The grain of the base material 3 can be seen through the coating layer 5.
Δ: The grain of the base material 3 is seen through the coating layer 5 in a blurred manner.

×: The grain of the base material 3 is not visible.
5. Other Embodiments Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be implemented in various modifications.

For example, another coating film may be formed on top of the second coating film 13.

1...building material, 3...substrate, 5...coating layer, 5A...center, 5B...surface, 5C...non-containing portion, 7...coating film, 9...glass fiber portion, 9A...surface, 11...first coating film, 13...second coating film

Claims (4)

A substrate;
A coating layer formed on the surface of the substrate;
Equipped with
The coating layer is
A coating film that foams when heated;
A glass fiber portion made of a glass fiber cloth or a glass fiber nonwoven fabric, at least a portion of which is embedded in the coating film;
Equipped with
The mass per unit area of the coating film is 250 g/m ² or more and 550 g/m ² or less,
The mass per unit area of the coating film that is impregnated in the glass fiber portion or that is located on the surface side of the glass fiber portion is 75 g/ ^m2 or more and 197 g/m2 ^or less.
Building materials. A substrate;
A coating layer formed on the surface of the substrate;
Equipped with
The coating layer is
A coating film that foams when heated;
A glass fiber portion made of a glass fiber cloth or a glass fiber nonwoven fabric, at least a portion of which is embedded in the coating film;
Equipped with
The coating film contains (A) a water-soluble melamine resin, (B) a condensation polymerization phosphate ester, (C) one or more of phosphoric acid, boric acid, an ammonium salt, and ammonia, and (D) urea.
Building materials. The building material according to claim 2 ,
The mass per unit area of the coating film is 250 g/m ² or more and 550 g/m ² or less,
The mass per unit area of the coating film that is impregnated in the glass fiber portion or that is located on the surface side of the glass fiber portion is 75 g/ ^m2 or more and 197 g/ ^m2 or less.
Building materials. The building material according to any one of claims 1 to 3 ,
The coating layer includes a portion that does not include the glass fiber portion on the substrate side.
Building materials.

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