JP2010150767A - Building material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a building material which is excellent in weatherability, harmful-gas degradability, suppression of propagation of mold and algae, and various desired coating characteristics (ultraviolet absorptivity, transparency, coating strength, etc.), while preventing the erosion of a building material base (particularly an organic base material). <P>SOLUTION: This building material includes the building material base, and a photocatalytic layer which is provided on the building material base. The photocatalytic layer contains ≥1 pt.mass and <20 pts.mass of photocatalytic particles, and >70 pts.mass and ≤99 pts.mass of inorganic oxide particles. Additionally, a silver component and a copper component are contained in such a manner that a mass ratio of Ag<SB>2</SB>O/CuO brings about the relationship: 0/100<[Ag<SB>2</SB>O/CuO]<50/50. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a building material that is particularly suitable for the use of exterior materials such as buildings, and has excellent weather resistance, harmful gas decomposability, mold and algae growth control, and various coating properties.

  In recent years, photocatalysts such as titanium oxide have been used for building materials such as exterior materials for buildings. By using photocatalyst, it is possible to decompose various harmful substances using light energy, or to make the surface of the building material base coated with photocatalyst hydrophilic and easily wash away the dirt adhering to the surface with water. . The following are known as techniques for obtaining a building material coated with such a photocatalyst.

  A technique for imparting hydrophilicity to the surface of a synthetic resin or the like using an aqueous dispersion containing photocatalytic metal oxide particles, colloidal silica, and a surfactant is known (Patent Document 1 (Japanese Patent Application Laid-Open No. Hei 5 (1994)). 11-14432 publication). In this technique, hydrophilicity is enhanced by containing a surfactant in a large amount of 10 to 25% by weight. Moreover, the cloudiness by the irregular reflection of light is prevented by making a film thickness into 0.4 micrometer or less.

A technique for obtaining a photocatalyst by forming a coating film containing silica sol as a binder component and photocatalytic titanium dioxide on a substrate is also known (see Japanese Patent Application Laid-Open No. 11-169727). In this technique, the amount of silica sol added is ₂₀ to 200 parts by weight with respect to titanium dioxide on the basis of SiO ₂ , and the content ratio of titanium dioxide is high. In addition, the particle size of silica sol is as small as 0.1 to 10 nm.

  There is also known a technique for forming a photocatalyst coating film by transmitting 50% or more of light having a wavelength of 500 nm and blocking 80% or more of light having a wavelength of 320 nm by using a photocatalyst paint (Japanese Patent Application Laid-Open No. 2004-359902). No.)). In this technique, an organosiloxane partial hydrolyzate is used as a binder of a photocatalyst coating, and the blending amount is preferably 5 to 40% by weight of the entire coating composition.

  A technique is known in which metallic silver and metallic copper or ions thereof are added to a photocatalyst layer to impart a deodorizing, antibacterial, and antifungal function (see Patent Document 4 (Patent No. 3555992)).

  A technique for increasing the photocatalytic activity by adding silver, copper, zinc, platinum or the like to the photocatalyst layer is known (see Patent Document 5 (Japanese Patent Laid-Open No. 11-169726)), (Patent Document 6 (International Publication No. 00 / No. 06300 pamphlet)).

  By the way, when the base material of a photocatalyst layer is comprised with an organic material, the problem that an organic material is decomposed | disassembled or deteriorated by the photocatalytic activity of a photocatalyst is known conventionally. In order to cope with this problem, a technique for protecting an underlying carrier from degradation due to photocatalysis by providing an adhesive layer such as a silicon-modified resin between the photocatalyst layer and the carrier is known (Patent Document 7 (International Publication 97/00134 pamphlet)).

Japanese Patent Application Laid-Open No. 11-14432 JP 11-169727 A JP 2004-359902 A Japanese Patent No. 355992 JP-A-11-169726 International Publication No. 00/06300 Pamphlet WO97 / 00134 pamphlet

The present inventors now include photocatalyst particles of 1 part by mass or more and less than 20 parts by mass, inorganic oxide particles of more than 70 parts by mass and 99 parts by mass or less, and further containing a silver component and a copper component with Ag ₂ O. By forming a photocatalyst layer on the building material substrate so as to have a relationship of 0/100 <[Ag ₂ O / CuO] <50/50 by mass ratio as / CuO, a building material substrate (especially an organic substrate) ), And building materials with excellent weather resistance, harmful gas decomposability, mold and algae growth control, and various desired coating properties (ultraviolet absorption, transparency, film strength, etc.) can be obtained. Obtained knowledge.

  Therefore, the object of the present invention is to prevent erosion of building material substrates (especially organic substrates), weather resistance, harmful gas decomposability, mold and algae growth control, and various desired coating properties (ultraviolet absorption, transparency) It is to provide a building material excellent in film strength and the like.

That is, the building material according to the present invention is a building material provided with a building material base and a photocatalyst layer provided on the building material base, wherein the photocatalyst layer is 1 part by weight or more and less than 20 parts by weight, and 70 The photocatalyst particles, the inorganic oxide particles, and the hydrolysis of inorganic oxide particles that are greater than 99 parts by mass and less than 99 parts by mass and a polymer of hydrolyzable silicone that is 0 to 10 parts by mass in terms of silica. The total amount of the silicone equivalent of the functional silicone is 100 parts by mass, and further, the silver component and the copper component are expressed as Ag ₂ O / CuO in a mass ratio of 0/100 <[Ag ₂ O / CuO] <. It is included so as to have a 50/50 relationship.

Building material A building material according to the present invention is a building material comprising a building material base and a photocatalyst layer provided on the building material base, wherein the photocatalyst layer is 1 part by weight or more and less than 20 parts by weight, and 70 parts by weight. More than 99 parts by mass of inorganic oxide particles and 0 to 10 parts by mass of hydrolyzable silicone polymer in terms of silica, the photocatalyst particles, the inorganic oxide particles and the hydrolyzable The total amount of silica in terms of silica is 100 parts by mass, and the silver component and the copper component are further expressed as Ag ₂ O / CuO in a mass ratio of 0/100 <[Ag ₂ O / CuO] <50. It is included so as to have a relationship of / 50. With this configuration, weathering, harmful gas decomposability, mold and algae growth control, and various desired coating properties (ultraviolet absorption, transparency, film strength, etc.) are prevented while preventing erosion of the building material substrate (especially organic substrate). It is possible to obtain an excellent building material.

  The reason why these excellent effects are realized at the same time is not clear, but is thought to be as follows. However, the following description is merely a hypothesis, and the present invention is not limited by the following hypothesis.

When an appropriate amount of ultraviolet rays is irradiated in a situation where a photocatalyst, a copper compound, and a silver compound coexist, it is considered that the photocatalyst and ionic copper directly affect the antifungal property. That is, the addition of copper in the ionic state to the photocatalyst reduces the probability of recombination of holes and electrons generated by the photoexcitation reaction of the photocatalyst, thereby increasing the antifungal effect based on the photocatalyst and the inherent antifungal effect of copper in the ionic state. Exhibits excellent antifungal effect by overlapping. In contrast, when ionic silver is added such that 0/100 <[Ag ₂ O / CuO] <50/50, the silver is reduced by the electrons generated by the photocatalyst, so the charge separation efficiency. Is further improved, and the fungicidal effect is considered to increase.

  The three-part coexistence of the photocatalyst, ionic copper and ionic silver provides an effective antifungal effect even when the amount of photocatalyst is reduced. Therefore, in the photocatalyst layer having the above composition system, it is possible to simultaneously exhibit prevention of erosion and improvement of weather resistance against the building material base (particularly, organic base) while exhibiting the antifungal effect.

  Furthermore, since photocatalyst particles are basically composed of two types of particles, photocatalyst particles and inorganic oxide particles, there are abundant gaps between the particles. When using a large amount of hydrolyzable silicone or titanium alkoxide widely used as a binder for the photocatalyst layer, or when using a large amount of a surfactant, the gaps between such particles are densely filled, It is thought to prevent gas diffusion.

  The photocatalyst layer, however, the photocatalyst layer of the present invention contains (1) a total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone polymer, even if it does not contain or contains hydrolyzable silicone polymer. The total amount of the polymer of photocatalyst particles, inorganic oxide particles, and titanium alkoxide, even if it does not contain or contain the polymer of titanium alkoxide, and less than 10 parts by mass in terms of silica with respect to 100 parts by mass The amount of titanium dioxide is less than 10 parts by mass with respect to 100 parts by mass. (3) The polymer of the surfactant is not included or is not included, but the photocatalyst particles, the inorganic oxide particles, and the surfactant are polymerized. Or less than 10 parts by mass with respect to 100 parts by mass of the total amount of (4), more preferably, does not contain hydrolyzable silicone polymer, titanium alkoxide polymer, surfactant Even if included, the amount is less than 10 parts by mass with respect to 100 parts by mass of the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone polymer. Therefore, it is considered that the gaps between the particles can be sufficiently secured. Such a gap realizes a structure in which harmful gases such as NOx and SOx are likely to diffuse into the photocatalyst layer, and as a result, the harmful gas may be efficiently contacted with the photocatalyst particles and decomposed by the photocatalytic activity. Conceivable.

  As described above, a sufficient amount of gaps between particles in the photocatalyst layer are ensured to have air permeability, so that even if the amount of photocatalyst is reduced, an effective photocatalyst gas (for example, harmful gas such as NOx and SOx) ) Decomposition effect is demonstrated. Therefore, in the photocatalyst layer of the above composition system, erosion prevention and weather resistance improvement for the building material base (particularly organic base material) while exhibiting the antifungal effect and the effect of decomposing gas (for example, harmful gases such as NOx and SOx) by the photocatalyst Can be demonstrated simultaneously.

  Here, the amount of the photocatalyst in the photocatalyst layer is preferably 1% by mass or more and less than 20% by mass, more preferably 1% by mass or more and 15% by mass or less, and most preferably 1% by mass or more and 5% by mass or less. is there. By reducing the blending ratio of the photocatalyst particles in this way, the direct contact of the photocatalyst particles with the building material substrate can be reduced as much as possible to prevent erosion of the building material substrate (especially organic material) and weather resistance is also improved. It is thought to improve. Nevertheless, functions due to photocatalytic activity such as decomposability of harmful gas and ultraviolet absorption can be sufficiently exhibited.

  According to a preferred embodiment of the present invention, the photocatalyst particles preferably have an average particle size of 10 nm to 100 nm, more preferably 10 nm to 60 nm. The photocatalyst particles in this range have good crystallinity and high specific surface area, so the photocatalytic decomposition activity is high, and the interaction with ionic silver and ionic copper ions in the photocatalyst layer is also increased. However, the antifungal property is particularly enhanced in the composition system of the present invention. The average particle diameter is calculated as a number average value obtained by measuring the length of any 100 particles that enter a 200,000-fold field of view with a scanning electron microscope. As the particle shape, a true sphere is most preferable, but a substantially circular or elliptical shape is also preferable. In this case, the particle length is approximately calculated as ((major axis + minor axis) / 2). Within this range, weather resistance, harmful gas decomposability, and various desired film properties (ultraviolet absorption, transparency, film strength, etc.) are efficiently exhibited.

  The ionic silver and ionic copper present in the photocatalyst layer are either (1) present as a metal compound in the photocatalyst layer or (2) supported on the photocatalyst particles. Preferably, the presence of a metal compound in the photocatalyst layer is preferable because ions are not easily metallized over a long period of time. The valence of copper ions may be +1 or +2.

The compounding amounts of ionic silver and ionic copper present in the photocatalyst layer are converted to Ag ₂ O and CuO, respectively, and the mass ratio as Ag ₂ O / CuO is 0/100 <[Ag ₂ O / CuO] <50/50 is preferable, and 10/90 <[Ag ₂ O / CuO] <50/50 is more preferable. Thus, by adding silver ions in a state where there are many copper ions, a more excellent antifungal effect is exhibited.

The amount of copper silver and ionic state of the ion state of the photocatalyst particles of the photocatalyst layer is 5 wt% exceeds 0.5% by mass or less based on the total weight of the photocatalyst particles in terms of Ag 2 _O and CuO Those added are preferred. A photocatalyst layer with extremely good antifungal and antialgal properties can be obtained under irradiation of light that can excite a photocatalyst such as ultraviolet rays by exceeding 0.5% by mass.
Moreover, it becomes difficult to produce other problems, such as coloring of a photocatalyst layer, by being 5 mass% or less.

According to a preferred embodiment of the present invention, the content of the inorganic oxide particles in the photocatalyst layer is more than 70% by mass and 99% by mass or less, preferably 80% by mass or more and 95% by mass or less, more preferably It is 85 mass% or more and 95 mass% or less, More preferably, it is 90 mass% or more and 95 mass% or less.
By making inorganic oxide particles present in a large amount in the photocatalyst layer in this way, the amount of photocatalyst particles in the photocatalyst layer is relatively reduced to prevent erosion of the building material base (particularly organic base) and to improve weather resistance. be able to. At the same time, the space between the particles in the photocatalyst layer can be sufficiently ensured to have air permeability, and even if the amount of photocatalyst is reduced, the photocatalytic gas is effective (for example, harmful gases such as NOx and SOx). The decomposition effect can be exhibited. Therefore, in the photocatalyst layer of the above composition system, erosion prevention and weather resistance improvement for the building material base (particularly organic base material) while exhibiting the antifungal effect and the effect of decomposing the gas (for example, harmful gases such as NOx and SOx) by the photocatalyst. Can be demonstrated at the same time.

  According to a preferred embodiment of the present invention, the inorganic oxide particles have an average particle size of more than 5 nm and less than 40 nm, more preferably more than 5 nm and less than 40 nm, and further preferably 10 nm or more and less than 40 nm. The average particle diameter is calculated as a number average value obtained by measuring the length of any 100 particles that enter a 200,000-fold field of view with a scanning electron microscope. As the particle shape, a true sphere is most preferable, but a substantially circular or elliptical shape is also preferable. In this case, the particle length is approximately calculated as ((major axis + minor axis) / 2). Within this range, weather resistance, harmful gas decomposability, and various desired coating properties (such as UV absorption, transparency, and film strength) are efficiently exhibited, and the photocatalyst layer is transparent and has good adhesion. Can be obtained.

The photocatalyst particles used in the present invention are not particularly limited as long as they have photocatalytic activity, and all kinds of photocatalyst particles can be used. Examples of the photocatalyst particles include metal oxide particles such as titanium oxide (TiO ₂ ), ZnO, SnO ₂ , SrTiO ₃ , WO ₃ , Bi ₂ O ₃ , Fe ₂ O ₃ , and preferably titanium oxide. Particles, more preferably anatase type titanium oxide particles. Titanium oxide is harmless, chemically stable, and available at low cost. Titanium oxide has a high band gap energy, and therefore requires ultraviolet light for photoexcitation and does not absorb visible light in the process of photoexcitation, so that no color formation due to a complementary color component occurs. Titanium oxide is available in various forms such as powder, sol, and solution, but any form can be used as long as it exhibits photocatalytic activity.

  According to a preferred embodiment of the present invention, the photocatalyst layer preferably has a film thickness of 0.5 μm or more and 3 μm or less, more preferably 1.0 μm or more and 2.0 μm or less. Within such a range, the ultraviolet rays that reach the interface between the photocatalyst layer and the building material substrate are sufficiently attenuated, so that the weather resistance is improved. Moreover, since the photocatalyst particles having a lower content ratio than the inorganic oxide particles can be increased in the film thickness direction, harmful gas decomposability is also improved. Furthermore, excellent characteristics can be obtained in terms of ultraviolet absorption, transparency, and film strength.

  The inorganic oxide particles used in the present invention are not particularly limited as long as they are inorganic oxide particles capable of forming a layer together with photocatalyst particles, and any kind of inorganic oxide particles can be used. Examples of such inorganic oxide particles include single oxide particles such as silica, alumina, zirconia, ceria, yttria, magnesia, calcia, iron oxide, manganese oxide, nickel oxide, niobium oxide, tin oxide, and hafnia. And particles of complex oxides such as barium titanate and calcium silicate, and more preferably silica particles.

  The photocatalyst layer of the present invention preferably contains substantially no hydrolyzable silicone polymer, and more preferably does not contain at all. The hydrolyzable silicone is a general term for an organosiloxane having an alkoxy group and / or a partially hydrolyzed condensate thereof. However, as long as the harmful gas decomposability of the present invention can be ensured, it is allowed to contain a hydrolyzable silicone polymer as an optional component. That is, the content of the hydrolyzable silicone polymer in the photocatalyst layer is 0 part by mass or more and less than 10 parts by mass, preferably 0 part by mass or more and 5 parts by mass or less, and most preferably about 0% by mass.

The hydrolyzable silicone is preferably an organosiloxane having at least one reactive group selected from the group consisting of an alkoxy group, a halogen group and a hydrogen group.
These hydrolyzable silicones are cured by a dehydration condensation polymerization reaction by drying at room temperature or by heat treatment at 10 ° C. or more and 500 ° C. or less, resulting in a hard hydrolyzable silicone dried product, thus improving the wear resistance.
For the hydrolyzable silicone, a silicone (oligomer or polymer) having a reactive group at its terminal is preferably used by polymerizing a bifunctional silane, trifunctional silane, or tetrafunctional silane alone or in combination as a monomer unit. Although it can be used, in particular, a silicate obtained by polymerizing only a tetrafunctional silane unit (SiX ₄ , X is at least one reactive group selected from the group of an alkoxy group, a halogen group, and a hydrogen group) (hereinafter referred to as a tetrafunctional group). (Referred to as a functional silicone). Use of tetrafunctional silicone is preferred because the hydrophilicity of the photocatalyst layer is improved and self-cleaning properties are exhibited at the same time. As the tetrafunctional silicone, alkyl silicates such as methyl silicate, ethyl silicate and isopropyl silicate can be suitably used.

  The photocatalyst layer of the present invention preferably does not substantially contain a polymer of titanium alkoxide, and more preferably does not contain at all. However, as long as the harmful gas decomposability of the present invention can be ensured, it is allowed to contain a polymer of titanium alkoxide as an optional component. That is, the content of the polymer of titanium alkoxide in the photocatalyst layer is 0 part by weight or more and less than 10 parts by weight, preferably 0 part by weight or more and 5 parts by weight or less, and most preferably about 0 part by weight. %.

  The photocatalyst layer may contain a surfactant as an optional component. The surfactant in the photocatalyst layer may be contained in the photocatalyst layer in an amount of 0% by mass to less than 10% by mass, preferably 0% by mass to 8% by mass, more preferably 0% by mass to 6% by mass. It is as follows. One of the effects of the surfactant is leveling to the building material substrate. In applications where this leveling effect is required, such as painting over a large area, the combination of the coating liquid and building material substrate The amount may be appropriately determined within the above-mentioned range, but the lower limit in the photocatalyst at that time is preferably 0.1% by mass. This surfactant is an effective component for improving the wettability of the photocatalyst coating liquid, but in the photocatalyst layer formed after coating and drying, it is an inevitable impurity that no longer contributes to the effect of the building material of the present invention. Therefore, the upper limit value in the photocatalyst is less than 10% by mass, preferably less than 8% by mass, more preferably 6% by mass or less. That is, the surfactant may be used within the above-mentioned content range depending on the wettability required for the photocatalyst coating liquid, and the surfactant is substantially or not included if the wettability is not a problem. Most preferably (0% by mass). Surfactants to be used are nonionic surfactants, anionic surfactants, and cationic surfactants in consideration of the dispersion stability of photocatalysts and inorganic oxide particles, and wettability when coated on the intermediate layer. Among these, amphoteric surfactants can be appropriately selected, but nonionic surfactants are particularly preferred among them, and ether-type nonionic surfactants and ester-type nonions are more preferred among them. Surfactants, polyalkylene glycol nonionic surfactants, fluorine-based nonionic surfactants, and silicon-based nonionic surfactants.

  The building material base used in the present invention may be various materials regardless of inorganic materials or organic materials as long as the photocatalyst layer can be formed thereon, and the shape thereof is not limited. Preferred examples of the building material base include metals such as aluminum, stainless steel, and steel, ceramic, glass, plastic, rubber, stone, cement, concrete, fiber, fabric, wood, paper, brick, glazed tile, glazed tile, Crystallized glass, glass block, lightweight cellular concrete board, asbestos cement, calcium silicate board, reinforced concrete board, slate board, gypsum board board; combinations of decorative boards, painted boards, etc., laminates of laminated steel sheets, etc., Those having at least one layer of coating on the surface thereof may be mentioned. The building material can be used for both interior use and exterior use, but is particularly suitable for exterior use because sunlight can be used effectively.

  According to a preferred aspect of the present invention, a building material substrate having at least a surface formed of an organic material can be used as the building material substrate, and the entire building material substrate is formed of an organic material or an inorganic material. It includes any one (for example, a decorative board) in which the surface of the building material base is coated with an organic material. According to the photocatalyst layer of the present invention, it is difficult to erode even to an organic material that is easily damaged by the photocatalytic activity. Therefore, a building material having an excellent function in one layer called a photocatalyst layer without interposing an intermediate layer. Can be manufactured. As a result, the time and cost required for manufacturing the building material can be reduced by the amount that the intermediate layer is not required.

  It is also preferable to provide an intermediate layer between the building material substrate and the photocatalyst layer. In particular, if a material having excellent weather resistance is used as the intermediate layer, the weather resistance when the building material base is a resin can be increased. As a substance excellent in weather resistance, a silicone-containing resin and a fluorine-containing resin are particularly preferable. In addition, it is preferable to use a material having excellent flexibility for the intermediate layer, so that even if the building material base has irregularities, appearance defects due to cracks during use are less likely to occur. As the substance having excellent flexibility in the intermediate layer, a resin containing a double chain structure, a resin containing a cyclic structure, a silicone containing a bifunctional monomer unit, and a silicone containing both organic crosslinking and inorganic crosslinking are particularly preferred.

The intermediate layer preferably comprises a silicone-modified resin, more preferably the intermediate layer comprises acrylic silicone.
By doing so, the weather resistance of the intermediate layer, durability against the photocatalytic reaction, flexibility and the like can be sufficiently exhibited.

  The intermediate layer preferably comprises a UV absorber. By doing so, the weather resistance of the building material base and the durability against the photocatalytic reaction can be further increased.

  The intermediate layer preferably comprises an organic antifungal agent. An organic antifungal agent is included in an intermediate layer separate from the photocatalyst layer, and a gap is provided between the particles of the photocatalyst layer. The anti-fungal function can be effectively exhibited without damaging each other.

Coating liquid The photocatalyst coating liquid according to the present invention is a coating liquid for producing the building material, and includes a solvent, 1 to 20 parts by mass of photocatalyst particles, and 70 to 99 parts by mass of inorganic. The total amount of oxide particles and hydrolyzable silicone polymer of 0 to 10 parts by mass in terms of silica is the photocatalyst particles, the inorganic oxide particles, and the hydrolyzable silicone in terms of silica. include such that 100 parts by weight, further, comprise a silver component and the copper _component, so that the relationship Ag 2 O / mass ratio as _{CuO 0/100 <[Ag 2 O /} CuO] <50/50 It becomes. The operational effects are as described above, and the preferred embodiments of the respective constituent components are also basically as described above.

  Here, as the solvent, any solvent capable of appropriately dispersing the above components can be used, and water and / or an organic solvent may be used, but water is particularly preferable because of its influence on the environment. The solid content concentration of the photocatalyst coating liquid of the present invention is not particularly limited, but it is preferably 1% by mass or more and less than 20% by mass because it is easy to apply. The components in the photocatalyst coating composition are analyzed by separating the coating solution into particle components and filtrate by ultrafiltration, and analyzing each by infrared spectroscopic analysis, gel permeation chromatography, fluorescent X-ray spectroscopic analysis, etc. It can be evaluated by analyzing the spectrum.

Further, as the photocatalyst particles, the particles described in the section “Building material” can be used. That is, examples of the photocatalyst particles include metal oxide particles such as titanium oxide (TiO ₂ ), ZnO, SnO ₂ , SrTiO ₃ , WO ₃ , Bi ₂ O ₃ , Fe ₂ O ₃ , preferably Titanium oxide particles, more preferably anatase type titanium oxide particles. The preferable blending amount is 1% by mass or more and less than 20% by mass, more preferably 1% by mass or more and 15% by mass or less, and most preferably 1% by mass or more and 5% by mass with respect to the solid content in the coating liquid. It is as follows. Moreover, the preferable average particle diameter of photocatalyst particle is 10 nm or more and 100 nm or less, More preferably, it is 10 nm or more and 60 nm or less.

  Further, as the inorganic oxide particles, the particles described in the section “Building material” can be used. That is, examples of the inorganic oxide particles include single oxide particles such as silica, alumina, zirconia, ceria, yttria, magnesia, calcia, iron oxide, manganese oxide, nickel oxide, niobium oxide, tin oxide, and hafnia; And composite oxide particles such as barium titanate and calcium silicate, and more preferably silica particles. The content of the inorganic oxide particles with respect to the solid content in the coating liquid is more than 70% by mass and 99% by mass or less, preferably 80% by mass or more and 95% by mass or less, more preferably 85% by mass or more. It is 95 mass% or less, More preferably, it is 90 to 95 mass%. The average particle size of the inorganic oxide particles is preferably more than 5 nm and less than 40 nm, more preferably more than 5 nm and less than 40 nm, and still more preferably 10 nm or more and less than 40 nm. These inorganic oxide particles are preferably in the form of an aqueous colloid using water as a dispersion medium; or an organosol dispersed in a hydrophilic solvent such as ethyl alcohol, isopropyl alcohol, or ethylene glycol, and particularly preferably. Colloidal silica.

As the copper compound and the silver compound, the blends described in the section “Building material” can be used. Copper compounds and silver compounds include copper-containing complexes, silver-containing complexes, copper amine compounds, silver amine compounds, copper hydroxy compounds, silver hydroxy compounds, copper carboxy compounds, silver carboxy compounds, copper organic acids Compounds, silver organic acid compounds, silver and copper complexes, silver and copper amine compounds, silver and copper hydroxy compounds, silver and copper carboxy compounds, silver and copper organic acid compounds, and the like can be suitably used. The valence of the copper ion may be +1 or +2. The compounding amounts of ionic silver and ionic copper present in the photocatalyst layer are converted to Ag ₂ O and CuO, respectively, and the mass ratio as Ag ₂ O / CuO is 0/100 <[Ag ₂ O / CuO] <50/50 is preferable, and 10/90 <[Ag ₂ O / CuO] <50/50 is more preferable. The compounding amount of ionic silver and ionic copper with respect to the photocatalyst particles is preferably such that the total amount converted to Ag ₂ O and CuO exceeds 0.5% by mass and added to 5% by mass or less with respect to the photocatalyst particles. .

  As other optional components, hydrolyzable silicone, titanium alkoxide, and surfactant can be added to the photocatalyst coating solution.

  The hydrolyzable silicone is preferably contained in an amount of 0% by mass or more and less than 10% by mass in terms of silica in the solid content in the photocatalyst coating liquid. More preferably, it is 0 mass part% or more and 5 mass parts or less, Most preferably, it is about 0 mass%.

  The titanium alkoxide is preferably contained in an amount of 0% by mass or more and less than 10% by mass in terms of titanium dioxide in the solid content in the photocatalyst coating liquid. More preferably, it is 0 mass part% or more and 5 mass parts or less, Most preferably, it is about 0 mass%.

  It is preferable to contain a surfactant in an amount of 0% by mass to less than 10% by mass with respect to the solid content in the photocatalyst coating liquid. More preferably, it is 0 mass part or more and 8 mass parts or less, More preferably, it is 0 mass part or more and 6 mass parts or less, Most preferably, it is about 0 mass%.

  Furthermore, the photocatalyst coating liquid contains at least one selected from the group of hydrolyzable silicone, titanium alkoxide, and surfactant as an optional component, and the total content thereof is based on the solid content in the photocatalyst coating liquid. 0% by mass or more and less than 10% by mass, more preferably 0% by mass or more and 5% by mass or less, and most preferably about 0% by mass (wherein the hydrolyzable silicone is equivalent to silica and the titanium alkoxide is titanium dioxide) It is more preferable that the amount be converted).

Manufacturing method of building material The building material of this invention can be easily manufactured by apply | coating the photocatalyst coating liquid of this invention on a building material base | substrate. As a method for coating the photocatalyst layer, generally used methods such as brush coating, roller, spray, roll coater, flow coater, dip coating, flow coating, screen printing, electrodeposition, vapor deposition and the like can be used. After the coating liquid is applied to the building material substrate, it may be dried at room temperature, or may be heat-dried as necessary, but when heated until the sintering proceeds, the voids between the particles are reduced and sufficient photocatalytic activity is obtained. You can't get it. In this invention, drying temperature is 10 degreeC or more and 500 degrees C or less, and an upper limit may be suitably set according to the kind of building material base | substrate. When the resin is contained in at least a part of the building material base, a preferable drying temperature is 10 ° C. or higher and 200 ° C. or lower in consideration of the heat resistant temperature of the resin. As described above, according to the photocatalyst layer of the present invention, the building material of the present invention is difficult to erode even to an organic material that is easily damaged by photocatalytic activity. The building material which has the function excellent in the layer can be manufactured. As a result, the time and cost required for manufacturing the building material can be reduced by the amount that the intermediate layer is not required.

<Example A>
The present invention will be specifically described based on the following examples, but the present invention is not limited to these examples.
In the following examples, the raw materials used for preparation of the photocatalyst coating liquid are as follows.
Photocatalyst particles / titania aqueous dispersion (average particle diameter: 42 nm, basic) (used in Examples 1 to 11, Examples 14 to 28, and Example 34)
Ag / Cu-containing titania aqueous dispersion: a photocatalytic titania aqueous dispersion in which the total amount of silver compound and copper compound converted to Ag ₂ O and CuO is added in the following mass% with respect to titania (average particle diameter: 48nm, basic,)
0.5% by mass (used in Examples 29 to 33 and Example 35)
3% by weight (used in Examples 12-13, 36, 38, 39)
・ 5% by mass (used in Example 37)
Inorganic oxide particles / water-dispersed colloidal silica (average particle size: 26 nm, basic) (used in Examples 1-21, 23, and 25-39)
Water-dispersed colloidal silica (average particle size: 14 nm, basic) (used in Example 22)
Water-dispersed colloidal silica (average particle size: 5 nm, basic) (used in Example 24)
Hydrocondensable silicone / tetramethoxysilane polycondensate (SiO ₂ equivalent concentration: 51 mass%, solvent: methanol, water)
Surfactant / polyether-modified silicone surfactant

Examples 1 to 7: Evaluation of weather resistance (reference)
A building material provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a building material base. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which carbon black powder is added on a float plate glass and sufficiently drying and curing it. On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, water as a solvent, and a polyether-modified silicone surfactant are mixed at a blending ratio shown in Table 1, A photocatalytic coating solution was obtained. In addition, this photocatalyst coating liquid does not contain hydrolysable silicone. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was spray-coated on the colored organic coating body previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm in any of Examples 1 to 7.

  The building material having a size of 50 × 100 mm thus obtained was subjected to a weather resistance test as follows. The building material was thrown into a sunshine weatherometer (S-300C, manufactured by Suga Test Instruments) defined in JIS B7753. After 300 hours, the test piece was taken out, the color difference was measured before and after the acceleration test with a color difference meter ZE2000 manufactured by Nippon Denshoku, and the degree of color change was evaluated by comparing the Δb values.

  The obtained results were as shown in Table 1. Here, G in the table indicates that the color has hardly changed, and NG indicates that the Δb value has shifted to the plus side (yellowing side). As shown in Table 1, it was found that by setting the content of the photocatalyst in the photocatalyst layer to less than 20 parts by mass, the photocatalyst layer has sufficient weather resistance even when the photocatalyst layer is coated on the organic substrate.

Examples 8 to 11: Evaluation of harmful gas decomposability (reference)
A building material provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a building material base. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which carbon black powder is added on a float plate glass and sufficiently drying and curing it. On the other hand, polycondensation of titania aqueous dispersion as photocatalyst, water-dispersed colloidal silica as inorganic oxide, water as solvent, polyether-modified silicone surfactant, and tetramethoxysilane as hydrolyzable silicone Were mixed at a blending ratio shown in Table 2 to obtain a photocatalyst coating solution. In addition, the photocatalyst coating liquid of Example 8 and Example 10 does not contain hydrolysable silicone. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was spray-coated on the colored organic coating body previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness (μm) of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm in any of the examples.

The thus obtained building material having a size of 50 × 100 mm was subjected to a gas decomposability test as follows. The building material was irradiated with BLB light of 1 mW / cm ² as a pretreatment for 12 hours or more. One coated body sample was set in the reaction vessel described in JIS R1701. NO gas was mixed with air adjusted to 25 ° C. and 50% RH so as to be about 1000 ppb, and introduced into a light-shielded reaction vessel for 20 minutes. Thereafter, BLB light adjusted to 3 mW / cm ² was irradiated for 20 minutes while the gas was introduced. Thereafter, the reaction vessel was shielded from light again with the gas introduced. The NOx removal amount was calculated according to the following formula from the NO and NO ₂ concentrations before and after the BLB light irradiation.
NOx removal amount = [NO (after irradiation) −NO (at irradiation)] − [NO ₂ (at irradiation) −NO ₂ (after irradiation)]

  The obtained results were as shown in Table 2. Here, G in the table represents a NOx removal amount of 400 ppb or more, and NG represents a NOx removal amount of 10 ppb or less. As shown in Table 2, when the photocatalyst layer was composed of photocatalyst particles and an inorganic oxide and substantially free of hydrolyzable silicone, good NOx decomposability was exhibited. On the other hand, those containing 10 parts by mass of hydrolyzable silicone were found to lose NOx decomposability.

Examples 12 to 21: Measurement of linear transmittance and ultraviolet shielding rate A building material provided with a photocatalyst layer was produced as follows. First, a float plate glass having a transmittance of 94% at a wavelength of 550 nm was prepared as a building material base. On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, water as a solvent, and 6 parts by mass of polyether with respect to 100 parts by mass of the total amount of photocatalyst particles and inorganic oxide particles. The modified silicone surfactant was mixed at a blending ratio shown in Table 3 to obtain a photocatalyst coating liquid. This photocatalyst coating liquid does not contain hydrolyzable silicone. In Examples 12 and 13, Ag / Cu-containing titania aqueous dispersions were used as photocatalysts. In Examples 14 to 21, titania aqueous dispersions containing no silver compound and copper compound were used. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was spray-coated on the float plate glass previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness (μm) of the photocatalyst layer was measured by observation with a scanning electron microscope, the values shown in Table 3 were obtained.

  With respect to the building material having a size of 50 × 100 mm obtained in this way, the measurement of the linear (550 nm) transmittance and the ultraviolet ray (300 nm) shielding rate was carried out as follows. Ultraviolet / visible / near infrared spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) ).

The obtained results were as shown in Table 3. Here, the evaluation criteria of the linear transmittance and the ultraviolet shielding rate were as follows.
<Linear transmittance>
A: Linear (550 nm) transmittance is 97% or more B: Linear (550 nm) transmittance is 95% or more and less than 97% <UV shielding factor>
a: Ultraviolet (300 nm) shielding rate of 80% or more b: Ultraviolet (300 nm) shielding rate of 30% or more and less than 80% c: Ultraviolet (300 nm) shielding rate of less than 30% As shown in Table 3, in the photocatalyst layer When the content of the photocatalyst is 5 to 15 parts by mass, the film thickness is 3 μm or less, so that even if an Ag / Cu-containing titania aqueous dispersion is used for the photocatalyst, ultraviolet rays due to deterioration of organic matter are sufficiently shielded. It was also found that transparency can be secured.

Examples 22 to 24: Measurement of haze (reference)
A building material provided with a photocatalyst layer was produced as follows. First, a float plate glass having a transmittance of 94% at a wavelength of 550 nm was used as a building material substrate. On the other hand, a titania aqueous dispersion as a photocatalyst, water-dispersed colloidal silica as an inorganic oxide having various average particle diameters shown in Table 4, water as a solvent, and a polyether-modified silicone surfactant are listed in Table 4. To obtain a photocatalyst coating liquid. Therefore, this photocatalyst coating liquid does not contain hydrolyzable silicone. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was spin-coated on the above-mentioned building material substrate at 1000 rpm for 10 seconds and dried at 120 ° C. for 5 minutes to obtain a photocatalyst layer. The haze of the building material having a size of 50 × 100 mm thus obtained was measured using a haze meter (haze-gard plus manufactured by Gardner).

  The obtained results were as shown in Table 4. As shown in Table 4, it was found that the building materials of Examples 22 and 23 can suppress the haze value to less than 1% and ensure transparency.

Examples 25 to 28: Evaluation of influence by addition of surfactant (reference)
A building material provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a building material base. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which carbon black powder is added on a float plate glass and sufficiently drying and curing it. On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, water as a solvent, and a polyether-modified silicone surfactant are mixed at a blending ratio shown in Table 5, A photocatalytic coating solution was obtained. In addition, this photocatalyst coating liquid does not contain hydrolysable silicone. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was spray-coated on the colored organic coating body heated to 50 to 60 ° C. in advance, and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness (μm) of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm in any of Examples 25 to 28.

The thus obtained building material having a size of 50 × 100 mm was subjected to a gas decomposability test as follows. As a pretreatment, the photocatalyst was irradiated with 1 mW / cm ² of BLB light for 12 hours or more. One coated body sample was set in the reaction vessel described in JIS R1701. NO gas was mixed with air adjusted to 25 ° C. and 50% RH so as to be about 1000 ppb, and introduced into a light-shielded reaction vessel for 20 minutes. Thereafter, BLB light adjusted to 3 mW / cm ² was irradiated for 20 minutes while the gas was introduced. Thereafter, the reaction vessel was shielded from light again with the gas introduced. The NOx removal amount was calculated according to the following formula from the NO and NO ₂ concentrations before and after the BLB light irradiation.
NOx removal amount = [NO (after irradiation) −NO (at irradiation)] − [NO ₂ (at irradiation) −NO ₂ (after irradiation)]

  The results obtained were as shown in Table 5. Here, the NOx removal rate in the table is relatively shown with the removal amount of Example 26 as 100. As shown in Table 5, it was found that the removal rate was lowered by increasing the amount of the surfactant added.

Examples 29 to 34: Evaluation of antifungal property by silver compound and copper compound-1
A building material provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a building material base. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which a white pigment is added on a float plate glass and sufficiently drying and curing it. On the other hand, Ag / Cu-containing titania aqueous dispersion as a photocatalyst, water-dispersed colloidal silica as an inorganic oxide having an average particle size of 26 nm, water as a solvent, and a total amount of photocatalyst particles and inorganic oxide particles of 100 parts by mass 6 parts by mass of a polyether-modified silicone surfactant was mixed at a blending ratio shown in Table 6 to obtain a photocatalyst coating solution. This photocatalyst coating liquid does not contain hydrolyzable silicone. In Examples 29 to 33, an Ag / Cu-containing titania aqueous dispersion in which the compounding ratio of the silver compound and the copper compound was adjusted (all examples are copper compounds and example 33 is all silver compounds) was used. In Example 34, an aqueous titania dispersion containing no silver compound or copper compound was used. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

The obtained photocatalyst coating liquid was spray-coated on the colored organic coating body previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness (μm) of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm in any of Examples 29 to 34. After pre-treatment of these building materials with 1 mW / cm ² of BLB light for 24 hours, the following antifungal test was performed.

The antifungal property of the building material having a size of 50 × 50 mm thus obtained was evaluated as follows. Aspergillus niger (NBRC6341) pre-cultured at 25 ° C. for 7 to 14 days on a potato dextrose agar medium as a test bacterium, this was dispersed in physiological saline containing 0.005% by weight of dioctyl sodium sulfosuccinate, and a spore suspension It was created.

The spore suspension was dropped into the building material obtained by the above method so as to be 4 to 6 × 10 ⁵ pieces / mL per test piece to obtain an anti-mold test piece. According to the film adhesion method described in JIS R1702 (2006), this test piece was covered with an adhesion film, placed in a petri dish capable of moisture retention, and moisturized glass was placed and used for the test.

The test piece was installed in the petri dish under BLB light irradiation, and irradiated with BLB light for 24 hours so that the surface of the building material was 0.4 mW / cm ² .

  After 24 hours of irradiation, the spore suspension was collected and cultured on a potato dextrose agar medium, and the number of surviving bacteria was counted. The antifungal property was obtained by determining the difference between the logarithmic value of the number of surviving bacteria obtained in Examples 29 to 34 and the logarithmic value of the number of surviving bacteria of the photocatalyst-untreated specimen.

  The test results are shown in Table 6. Here, the antifungal activity value in the table is the value of the difference between the logarithmic value of the survival cell count obtained in Examples 29 to 34 and the logarithmic value of the survival cell count of the photocatalyst unprocessed test specimen, The larger the value, the higher the antifungal property. The antifungal activity value is higher in the example prepared using the Ag / Cu-containing titania aqueous dispersion than in the example in which only the silver compound or only the copper compound is added. It was confirmed that high antifungal performance was obtained by mixing. In particular, in Examples 29 and 30, the antifungal activity value has exceeded 2.

Examples 35 to 37: Evaluation of antifungal property by silver compound and copper compound-2
A building material provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a building material base. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which a white pigment is added on a float plate glass and sufficiently drying and curing it. On the other hand, Ag / Cu-containing titania aqueous dispersion as a photocatalyst, water-dispersed colloidal silica as an inorganic oxide having an average particle size of 26 nm, water as a solvent, and a total amount of photocatalyst particles and inorganic oxide particles of 100 parts by mass 6 parts by mass of a polyether-modified silicone surfactant was mixed at a blending ratio shown in Table 7 to obtain a photocatalyst coating solution. This photocatalyst coating liquid does not contain hydrolyzable silicone. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

The obtained photocatalyst coating liquid was spray-coated on the colored organic coating body previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness (μm) of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm in any of Examples 35 to 37. After pre-treatment of these building materials with 1 mW / cm ² of BLB light for 24 hours, the following antifungal test was performed.

  About the building material of the magnitude | size of 50x50 mm obtained in this way, the antifungal evaluation was performed by the method similar to Examples 29-34.

  After 24 hours of irradiation, the spore suspension was collected and cultured on a potato dextrose agar medium, and the number of surviving bacteria was counted. Antifungal property was obtained by calculating the difference between the logarithmic value of the number of surviving bacteria obtained in Examples 35 to 37 and the logarithmic value of the number of surviving bacteria of the photocatalyst untreated specimen.

The test results are shown in Table 7. Here, the antifungal activity value in the table is the value of the difference between the logarithmic value of the survival cell count obtained in Examples 35 to 37 and the logarithmic value of the survival cell count of the photocatalyst untreated specimen, The larger the value, the higher the antifungal property. It was confirmed that high antifungal performance was obtained when the amount of [Ag ₂ O + CuO] was 0.5% by mass relative to the titanium oxide particles at 3% by mass and 5% by mass.

Example 38: Evaluation of harmful gas decomposability A building material provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a building material base. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which carbon black powder is added on a float plate glass and sufficiently drying and curing it. On the other hand, Ag / Cu-containing titania aqueous dispersion as a photocatalyst, water-dispersed colloidal silica as an inorganic oxide having an average particle size of 26 nm, water as a solvent, and a total amount of photocatalyst particles and inorganic oxide particles of 100 parts by mass 6 parts by mass of a polyether-modified silicone surfactant was mixed at a blending ratio shown in Table 8 to obtain a photocatalyst coating solution. This photocatalyst coating liquid does not contain hydrolyzable silicone. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was spray-coated on the colored organic coating body previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness (μm) of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm.

  About the building material of the magnitude | size of 50x100mm obtained in this way, the gas decomposability test was done by the method similar to Examples 8-11. The sample of Example 8 was subjected to the same measurement as a comparison.

  The obtained results were as shown in Table 8. Here, the NOx removal rate in the table is relatively shown with the removal amount of Example 8 being 100. As shown in Table 8, it was found that a sufficient removal rate could be obtained even when an Ag · Cu-containing titania aqueous dispersion as a photocatalyst was used.

Example 39: Evaluation of weather resistance A building material provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a building material base. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which carbon black powder is added on a float plate glass and sufficiently drying and curing it. On the other hand, Ag / Cu-containing titania aqueous dispersion as a photocatalyst, water-dispersed colloidal silica as an inorganic oxide having an average particle size of 26 nm, water as a solvent, and a total amount of photocatalyst particles and inorganic oxide particles of 100 parts by mass 6 parts by mass of a polyether-modified silicone surfactant was mixed at a blending ratio shown in Table 9 to obtain a photocatalyst coating solution. This photocatalyst coating liquid does not contain hydrolyzable silicone. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was spray-coated on the colored organic coating body previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes. Thus, a photocatalyst layer was formed to obtain a building material. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm.

  The building material having a size of 50 × 100 mm thus obtained was subjected to a weather resistance test in the same manner as in Examples 1 to 7.

  The obtained results were as shown in Table 9. Here, G in the table indicates that there was almost no discoloration. As shown in Table 9, it was found that even if an Ag / Cu-containing titania aqueous dispersion as a photocatalyst was used or a photocatalyst layer was coated on an organic substrate, the weather resistance was sufficient.

Example 40: Evaluation of coating film adhesion A building material provided with a photocatalyst layer was produced in the same manner as in Example 38. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm.

  About the building material of the magnitude | size of 50x100mm obtained in this way, the coating-film adhesiveness was evaluated as follows. The building material was immersed in a calcium hydroxide saturated solution at 20 ± 5 ° C. After 7 days had elapsed, the surface was dried indoors, and then a cellophane tape was affixed to the surface. After holding the tape at one end and pulling it off in a direction perpendicular to the surface, the surface of the coating film is observed with a digital microscope. I understood.

<Example B>
The present invention will be specifically described based on the following examples, but the present invention is not limited to these examples.
In the following examples, the intermediate layer coating solution was prepared by appropriately mixing one of the following silicone-modified acrylic resin materials, water, and a film-forming aid, and details are shown in Table 10. The film-forming aid concentration was 3% by mass with respect to the intermediate layer coating solution.
Silicone-modified acrylic resin dispersion having a silicon atom content of 10% by mass with respect to the solid content of the silicone-modified resin. Silicone modification having a silicon atom content of 0.2% by mass with respect to the solid content of the silicone-modified resin. Acrylic resin dispersion ・ Silicone-modified acrylic resin dispersion having a silicon atom content of 16.5% by mass based on the solid content of the silicone-modified resin.

  As the organic fungicide, a commercially available nitrogen-sulfur compound and a triazine compound were used, and the concentration of the fungicide was 0.5% by mass with respect to the intermediate layer coating solution.

In the following examples, the photocatalyst layer coating liquid was prepared by appropriately mixing the photocatalyst particles shown below, any inorganic oxide, water, and a surfactant. Details are shown in Table 11. The raw materials used are as follows.
Photocatalyst particles / titania water dispersion (average particle size: 42 nm, basic)
Ag / Cu-containing titania aqueous dispersion: photocatalytic titania aqueous dispersion in which the total amount of silver compound and copper compound converted to Ag ₂ O and CuO is 0 to 5% by mass with respect to titania (average particle diameter : 48 nm, basic)
Inorganic oxide particles / water-dispersed colloidal silica (average particle size: 14 nm, basic)
・ Water-dispersed colloidal silica (average particle size: 26 nm, basic)
Water-dispersed colloidal silica (average particle size: 5 nm, basic)
Water-dispersed colloidal silica (average particle size: 51 nm, basic)
Hydrocondensable silicone / tetramethoxysilane polycondensate (SiO ₂ equivalent concentration: 51 mass%, solvent: methanol, water)
Surfactant / polyether-modified silicone surfactant

Examples 41 to 48: Evaluation of gas decomposability (reference)
A building material provided with an intermediate layer containing an organic fungicide and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a building material base. The intermediate layer coating solution described in M-1 in Table 10 was spray-coated on a glass substrate previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes to obtain an intermediate layer. The solid content concentration of the resin in this M-1 solution was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in any of Examples 41 to 48.

  On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent are mixed at a blending ratio shown by T-1 to T-8 in Table 11 to form a photocatalytic coating. A liquid was obtained. The total solid content concentration of the photocatalyst, the inorganic oxide, and the hydrolyzable silicone in the photocatalyst coating liquid was 5.5% by mass. The obtained photocatalyst coating liquid was spray-coated on the intermediate layer coating body heated in advance to 50 ° C., and dried at 120 ° C. for 5 minutes. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm in any of Examples 41 to 48. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a building material.

The thus obtained building material having a size of 50 × 100 mm was subjected to a gas decomposability test as follows. The building material was irradiated with BLB light of 1 mW / cm ² as a pretreatment for 12 hours or more. One coated body sample was set in the reaction vessel described in JIS R1701. NO gas was mixed with air adjusted to 25 ° C. and 50% RH so as to be about 1000 ppb, and introduced into a light-shielded reaction vessel for 20 minutes. Thereafter, BLB light adjusted to 3 mW / cm ² was irradiated for 20 minutes while the gas was introduced. Thereafter, the reaction vessel was shielded from light again with the gas introduced. The NOx removal amount was calculated according to the following formula from the NO and NO ₂ concentrations before and after the BLB light irradiation.
NOx removal amount = [NO (after irradiation) −NO (at irradiation)] − [NO ₂ (at irradiation) −NO ₂ (after irradiation)]

  The obtained results were as shown in Table 12. As shown in Table 12, when the photocatalyst layer is composed of photocatalyst particles and an inorganic oxide and does not contain hydrolyzable silicone, good NOx decomposability was exhibited. On the other hand, those containing 10 parts by mass of hydrolyzable silicone were found to lose NOx decomposability. Moreover, even if the photocatalyst ratio in the photocatalyst layer was increased 2.5 times, the tendency was not changed.

Examples 49 and 50: Evaluation of algae resistance (reference)
A building material provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a building material base. An intermediate layer coating solution described in M-1 and M-2 of Table 10 was spray-coated on a glass substrate previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes to obtain an intermediate layer. The solid content concentration of the resin in the liquids M-1 and M-2 was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in both Examples 49 and 50.

  On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent were mixed at a blending ratio shown by T-4 in Table 11 to obtain a photocatalyst coating liquid. . The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass. The obtained photocatalyst coating liquid was spray-coated on the intermediate layer coating body heated in advance to 50 ° C., and dried at 120 ° C. for 5 minutes. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm in both Examples 49 and 50. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a building material.

  The building material having a size of 50 × 50 mm thus obtained was subjected to an algae-proof test as follows. Chlorella (NIES-642) was used as a substitute for algae. Inorganic salt medium was used as a nutrient source for chlorella during the test. In a petri dish, building materials were placed, water containing a certain amount of chlorella and an inorganic salt medium was added, the lid was capped, and the cells were cultured under a fluorescent lamp with an illuminance of 4000 lx at a temperature of 25 ° C. ± 2 ° C. A transparent acrylic plate was sandwiched between the petri dish and the fluorescent lamp to completely block the ultraviolet rays. Chlorella reproduction was compared and judged visually.

  The obtained results were as shown in Table 13. Here, ○ in the table indicates that no algae were visually observed, and x indicates that algae was visually observed.

Examples 51 to 53: Evaluation of transparency of coating film (reference)
A building material provided with a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a building material base. A titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent are mixed at a mixing ratio shown in T-4, T-9, and T-10 in Table 11, A photocatalytic coating solution was obtained. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass. After 1 g of the obtained photocatalyst coating liquid was dropped on a 50 × 50 mm plate glass, it was spin-coated at 1000 rpm for 10 seconds to obtain a coating film transparency test body.

  About the building material of the magnitude | size of 50x50mm obtained in this way, the haze value was measured in BYK-Gardner company make-gard plus.

  The obtained results were as shown in Table 14. From Table 14, it was found that the building materials of Examples 51 and 52 were able to suppress the haze value to less than 1% and ensure transparency.

Examples 54 to 56: Evaluation of adhesion of coating film (reference)
A building material provided with an intermediate layer containing an organic fungicide and a photocatalyst layer was produced as follows. First, a general-purpose epoxy resin primer was applied to a float glass sheet as a building material base, and a dried product was prepared. The intermediate layer coating solution described in M-1 in Table 10 was spray-coated on a glass substrate previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes to obtain an intermediate layer. The solid content concentration of the resin in the M-1 solution was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in any of Examples 54 to 56.

  On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent are mixed at a blending ratio shown by T-4, T-9, and T-11 in Table 11. Thus, a photocatalyst coating solution was obtained. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass. The obtained photocatalyst coating liquid was spray-coated on the intermediate layer coating body heated in advance to 50 ° C., and dried at 120 ° C. for 5 minutes. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm in any of Examples 54 to 56. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a building material.

  The building material having a size of 50 × 50 mm thus obtained was immersed in a saturated aqueous calcium hydroxide solution at room temperature for 18 hours. After washing with water and drying at 50 ° C. for 1 hour, a cellophane tape specified in JIS Z1522 is applied to the surface of the coating film, peeled off instantaneously in a vertical direction, the peeled surface is observed, and the film remains before and after It was confirmed.

  The obtained results were as shown in Table 15. Here, ○ in the table indicates that no photocatalyst layer peeling was observed, and Δ indicates that some photocatalyst layer peeling was observed. In the building materials of Examples 54 and 55, it was found that the photocatalyst layer had sufficient adhesion to the intermediate layer.

Examples 57 to 63: Evaluation of weather resistance of coating film-1 (reference)
A building material provided with an intermediate layer containing an organic fungicide and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a building material base. A glass substrate previously heated to 50 ° C. was spray-coated with an intermediate layer coating solution described in M-3 of Table 10 mixed with a color pigment, and dried at 120 ° C. for 5 minutes to obtain an intermediate layer.
The solid content concentration of the resin in the liquid was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in any of Examples 57 to 63.

  On the other hand, titania aqueous dispersion as a photocatalyst, water-dispersed colloidal silica as an inorganic oxide, and water as a solvent are T-1 to T-4, T-6, T-12, and T-13 in Table 11. To obtain a photocatalyst coating liquid. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass. The obtained photocatalyst coating liquid was spray-coated on the intermediate layer coating body heated in advance to 50 ° C., and dried at 120 ° C. for 5 minutes. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm in any of Examples 57 to 63. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a building material.

  The building material having a size of 50 × 100 mm thus obtained was subjected to a weather resistance test as follows. The building material was thrown into a sunshine weatherometer (S-300C, manufactured by Suga Test Instruments) defined in JIS B7753. After 300 hours, the test piece was taken out, the color difference was measured before and after the acceleration test with a color difference meter ZE2000 manufactured by Nippon Denshoku, and the degree of color change was evaluated by comparing the Δb values.

  The obtained results were as shown in Table 16. Here, G in the table indicates that the color has hardly changed, and NG indicates that the Δb value has shifted to the plus side (yellowing side). As shown in Table 16, by making the photocatalyst content in the photocatalyst layer less than 20 parts by mass, the photocatalyst layer has sufficient weather resistance even if the photocatalyst layer is applied to an intermediate layer having a small silicon atom content. I understood.

Examples 64 and 65: Evaluation of weather resistance of coating film-2 (reference)
A building material provided with an intermediate layer containing an organic fungicide and a photocatalyst layer was produced as follows. First, a general-purpose epoxy resin-based primer was applied to a galvanized steel sheet as a building material base and dried. The intermediate layer coating solution described in M-1 and M-4 of Table 10 was spray coated and dried at 120 ° C. for 5 minutes to obtain an intermediate layer. The solid content concentration of the resin in the M-1 and M-4 solutions was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in both examples 64 and 65.

  On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent were mixed at a blending ratio shown by T-4 in Table 11 to obtain a photocatalyst coating liquid. . The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass. The obtained photocatalyst coating liquid was spray-coated on the intermediate layer coating body heated in advance to 50 ° C., and dried at 120 ° C. for 5 minutes. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 0.5 μm in any of Examples 64 and 65. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a building material.

  The building material having a size of 50 × 100 mm thus obtained was subjected to a weather resistance test as follows. The building material was thrown into a metering weatherometer (M6T manufactured by Suga Test Instruments). The appearance of the test piece was confirmed after 150 hours.

  In Example 64 in which an acrylic modified silicone resin having a silicon atom content of 10% by mass with respect to the solid content of the silicone modified resin was used for the intermediate layer, no cracks were observed, the appearance was good, and sufficient weather resistance. It was found to have On the other hand, in Example 65 using an acrylic-modified silicone resin having a silicon atom content of 16.5% by mass, generation of cracks was partially observed.

Example 66: Evaluation of weather resistance of coating film-3 (reference)
A building material was created under the same conditions as in Example 64 except that the size of the building material base was 150 × 65 mm. About this building material, the weather resistance test was done as follows. The building material was thrown into a sunshine weatherometer (S-300C, manufactured by Suga Test Instruments) defined in JIS B7753. After 4500 hours had elapsed, the test piece was taken out, the color difference was measured with a color difference meter ZE2000 manufactured by Nippon Denshoku, and the ΔE value was calculated. Further, the water contact angle was measured with a contact angle meter (CA-X150, manufactured by Kyowa Interface Science). The ΔE value was calculated based on the method described in JIS Z8730.

  It was found that the building material obtained in the present invention has surprising weather resistance and super hydrophilicity, with a ΔE value of 0.5 and a water contact angle of 5 ° or less after 4500 hours of sunshine weatherometer. Moreover, the NOx gas decomposition and the adhesion of the coating film were almost the same level as in the initial stage.

Example 67: Evaluation of weather resistance of coating film-4 (reference)
About the building material created on the same conditions as Example 66, the weather resistance test was done as follows. The building material was exposed outdoors in Chigasaki City, Kanagawa Prefecture, with a 45 ° slope from the horizontal to the top, facing south. After about 500 days, the test piece was taken out and the color difference was measured with a color difference meter ZE2000 manufactured by Nippon Denshoku.

  It was found that the building material obtained in the present invention has an amazing antifouling property with a ΔE value of 0.5 or less after about 500 days after outdoor exposure.

Examples 68 to 73: Evaluation of antifungal property by silver compound and copper compound-1
A building material provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a building material base. An intermediate layer coating solution described in M-2 of Table 10 was spray-coated on a glass substrate previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes to obtain an intermediate layer. The solid content concentration of the resin in the liquid M-2 was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in any of Examples 68 to 73.

  On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent are mixed at a blending ratio shown in T-4 and T-14 to T-18 in Table 11. Thus, a photocatalyst coating solution was obtained. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass. In Examples 68 to 72, an Ag / Cu-containing titania aqueous dispersion in which the compounding ratio of the silver compound and the copper compound was adjusted was used (however, Example 71 was all a copper compound and Example 72 was a silver compound). In 73, the titania water dispersion which does not contain a silver compound and a copper compound was used.

The obtained photocatalyst coating liquid was spray-coated on the intermediate layer coating body heated in advance to 50 ° C., and dried at 120 ° C. for 5 minutes. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm in any of Examples 68 to 73. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a building material. After pre-treatment of these building materials with 1 mW / cm ² of BLB light for 24 hours, the following antifungal test was performed.

The antifungal property of the building material having a size of 50 × 50 mm thus obtained was evaluated as follows. Aspergillus niger (NBRC6341) pre-cultured at 25 ° C. for 7 to 14 days on a potato dextrose agar medium as a test bacterium, this was dispersed in physiological saline containing 0.005% by weight of dioctyl sodium sulfosuccinate, and a spore suspension It was created.

The spore suspension was dropped into the building material obtained by the above method so as to be 4 to 6 × 10 ⁵ pieces / mL per test piece to obtain an anti-mold test piece. According to the film adhesion method described in JIS R1702 (2006), this test piece was covered with an adhesion film, placed in a petri dish capable of moisture retention, and moisturized glass was placed and used for the test.

The test piece was installed in the petri dish under BLB light irradiation, and irradiated with BLB light for 24 hours so that the surface of the building material was 0.4 mW / cm ² .

  After 24 hours of irradiation, the spore suspension was collected and cultured on a potato dextrose agar medium, and the number of surviving bacteria was counted. The antifungal property was obtained by determining the difference between the logarithmic value of the survival cell count obtained in Examples 68 to 73 and the logarithmic value of the survival cell count of the untreated photocatalyst specimen subjected to the same test. .

  The test results are shown in Table 17. Here, the antifungal activity value in the table is the value of the difference between the logarithmic value of the survival cell count obtained in Examples 68 to 73 and the logarithmic value of the survival cell count of the photocatalyst untreated specimen, The larger the value, the higher the antifungal property. The antifungal activity value is higher in the example prepared using the Ag / Cu-containing titania aqueous dispersion than in the example in which only the silver compound or only the copper compound is added. It was confirmed that high antifungal performance was obtained by mixing.

Examples 74 and 75: Evaluation of antifungal property by silver compound and copper compound-2
A building material provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a building material base. An intermediate layer coating solution described in M-2 of Table 10 was spray-coated on a glass substrate previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes to obtain an intermediate layer. The solid content concentration of the resin in the liquid M-2 was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in both Example 74 and Example 75.

  On the other hand, an Ag / Cu-containing titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent are mixed at a blending ratio indicated by T-19 and T-21 in Table 11. Thus, a photocatalyst coating solution was obtained. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was formed into a film by the method similar to Example 68-73, and the photocatalyst body of Example 74 and Example 75 was obtained. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm in both Examples 74 and 75. About this photocatalyst body, antifungal evaluation was performed by the method similar to Examples 68-73.

The test results are shown in Table 18. The antifungal activity values of Example 69 are also shown in Table 18. It was confirmed that high antifungal performance was obtained when the amount of [Ag ₂ O + CuO] was 0.5% by mass, 3% by mass, and 5% by mass with respect to the titanium oxide particles.

Examples 76 and 77: Evaluation of antifungal property by silver compound and copper compound-3
A building material provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a building material base. An intermediate layer coating solution described in M-1 and M-2 of Table 10 was spray-coated on a glass substrate previously heated to 50 ° C. and dried at 120 ° C. for 5 minutes to obtain an intermediate layer. The solid content concentration of the resin in the liquid M-1 or M-2 was about 20% by mass. When the film thickness of the intermediate layer was measured by observation with a scanning electron microscope, it was about 10 μm in both Example 76 and Example 77.

  On the other hand, an Ag / Cu-containing titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, and water as a solvent are mixed at a blending ratio shown by T-20 in Table 11 to obtain a photocatalytic coating. A liquid was obtained. The total solid concentration of the photocatalyst and the inorganic oxide in the photocatalyst coating solution was 5.5% by mass.

  The obtained photocatalyst coating liquid was formed into a film by the method similar to Examples 68-73, and the photocatalyst body of Example 76 was obtained. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, it was about 1 μm in both Example 76 and Example 77. About this photocatalyst body, antifungal evaluation was performed by the method similar to Examples 68-73.

  The test results are shown in Table 19. In Example 77 in which the intermediate layer contained an organic antifungal agent, the effect of the antifungal agent was synergized, and the antifungal activity value was further increased.

Claims (6)

A building material comprising a building material substrate and a photocatalyst layer provided on the building material substrate,
The photocatalytic layer is
1 to 20 parts by mass of photocatalyst particles,
Inorganic oxide particles exceeding 70 parts by mass and 99 parts by mass or less;
The total amount of the photocatalyst particles, the inorganic oxide particles, and the hydrolyzable silicone in terms of silica is 100 parts by mass with respect to 0 to 10 parts by mass of the hydrolyzable silicone polymer in terms of silica. Including
Further, the silver component and the copper _component, comprising such a relation that Ag 2 O / 0/100 in weight ratio as _{CuO <[Ag 2 O / CuO} ] <50/50, building materials. A building material comprising a building material substrate and a photocatalyst layer provided on the building material substrate,
The photocatalytic layer is
1 to 20 parts by mass of photocatalyst particles,
Inorganic oxide particles exceeding 70 parts by mass and 99 parts by mass or less;
The total amount of the photocatalyst particles, the inorganic oxide particles, and the hydrolyzable silicone in terms of silica is 100 parts by mass with respect to 0 to 10 parts by mass of the hydrolyzable silicone polymer in terms of silica. Including
Further, the silver component and the copper _component, comprising such a relation that Ag 2 O / 10/90 by mass ratio as _{CuO <[Ag 2 O / CuO} ] <50/50, building materials.   The building material according to claim 1 or 2, wherein the photocatalyst layer further contains, as an optional component, a polymer of titanium alkoxide in an amount of 0% by mass or more and less than 10% by mass in terms of titanium dioxide.   The building material according to any one of claims 1 to 3, wherein the photocatalyst layer further contains a surfactant as an optional component in an amount of 0% by mass to less than 10% by mass.   5. The building material according to any one of 1 to 4, wherein the photocatalyst particles have an average particle size of 10 nm to 100 nm.   The building material according to claim 1, wherein the photocatalyst layer has air permeability.