JP2010099645A - Photocatalyst-coated body and photocatalytic coating liquid for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photocatalyst-coated body and a photocatalytic coating liquid which exert an excellent weatherability, harmful gas decomposability, and other desired characteristics (such as transparency and film strength), while preventing erosion of the substrate. <P>SOLUTION: The photocatalyst-coated body comprises a substrate and a photocatalytic layer provided on the substrate. The photocatalytic layer comprises photocatalytic particles and inorganic oxide particles, and has gaps between the particles in the layer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a photocatalyst-coated body excellent in high weather resistance, hydrophilicity, harmful gas decomposability, and various film properties for use in exterior materials such as buildings, and a photocatalyst coating liquid therefor.

  In recent years, photocatalysts such as titanium oxide have been used in many applications 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 substrate coated with photocatalyst hydrophilic and easily wash away dirt adhering to the surface with water. . The following are known as techniques for obtaining a photocatalyst-coated body 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 (for example, Patent Document 1 ( (See JP-A-11-14432). 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, for example, Patent Document 2 (Japanese Patent 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 of forming a photocatalytic coating film that transmits 50% or more of light having a wavelength of 500 nm and blocks 80% or more of light having a wavelength of 320 nm by using a photocatalyst coating (for example, Patent Document 3 (Japanese Patent Laid-Open No. 2004-2004)). 359902))). In this technique, an organosiloxane partial hydrolyzate is used as a binder of a photocatalyst coating material, and the blending amount is preferably 5 to 40% by mass of the entire coating composition.

  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 deterioration due to photocatalysis by providing an adhesive layer such as a silicon-modified resin between the photocatalyst layer and the carrier is known (for example, Patent Document 4). (See WO 97/00134 pamphlet).

Japanese Patent Application Laid-Open No. 11-14432 JP 11-169727 A JP 2004-359902 A WO97 / 00134 pamphlet

  The inventors of the present invention have recently constituted a photocatalyst layer with a specific composition containing photocatalyst particles and inorganic oxide particles at a specific mass ratio and containing no hydrolyzable silicone or keeping the amount as small as possible. , Photocatalyst-coated body excellent in high weather resistance, hydrophilicity, harmful gas decomposability, and various desired film properties (transparency, film strength, etc.) while suppressing erosion to the substrate (especially organic substrate) We obtained knowledge that

  Therefore, the object of the present invention is to provide high weather resistance, hydrophilicity, harmful gas decomposability, and various desired film properties (transparency, film strength, etc.) while preventing erosion of the substrate (especially organic substrate). An excellent photocatalyst-coated body and a photocatalyst coating liquid therefor are provided.

  That is, the photocatalyst-coated body according to the present invention is a photocatalyst-coated body including a base material and a photocatalyst layer provided on the base material, wherein the photocatalyst layer includes photocatalyst particles, inorganic oxide particles, A photocatalyst-coated body, wherein the photocatalyst layer has a gap between particles in the layer.

Moreover, the photocatalyst coating liquid by this invention is a photocatalyst coating liquid used for manufacture of the said photocatalyst coating body, Comprising: A photocatalyst which has an average particle diameter of 10 to 100 nm of 1 to 5 mass parts. Particles, greater than 85 parts by weight and less than 99 parts by weight of inorganic oxide particles, and 0 parts by weight or more and less than 10 parts by weight hydrolyzable silicone in terms of silica;
Is a photocatalyst coating liquid containing 100 parts by mass of the total amount of the photocatalyst particles, the inorganic oxide particles, and the hydrolyzable silicone in terms of silica.

Photocatalyst-coated body The photocatalyst-coated body according to the present invention is a photocatalyst-coated body comprising a base material and a photocatalyst layer provided on the base material, wherein the photocatalyst layer comprises photocatalyst particles, inorganic oxide particles, and And the photocatalyst layer has a gap between particles in the layer.

  The photocatalyst layer is composed of photocatalyst particles and inorganic oxide particles as the main components, and by actively providing gaps between the particles in the photocatalyst layer, the air permeability to the photocatalyst layer is improved, Decomposing substances such as NOx gas in the outside air and gas necessary for generating active oxygen such as oxygen and water vapor can be easily made effective in the vicinity of the photocatalyst particles. Thereby, gas decomposition characteristics by a photocatalyst such as excellent NOx decomposition action can be obtained.

  In addition to the structure described so far, the photocatalyst layer further includes a photocatalyst particle of more than 1 part by weight and less than 5 parts by weight, an inorganic oxide particle of more than 85 parts by weight and less than 99 parts by weight, and 0 part by weight or more and 10 parts by weight or more. The hydrolyzable silicone dried product of less than parts by mass so that the total amount of silica equivalents of the photocatalyst particles, the inorganic oxide particles, and the hydrolyzable silicone is 100 parts by mass. It is preferable to constitute a photocatalyst-coated body.

  That is, the mixing ratio of the photocatalyst particles in the photocatalyst layer is considerably less than the inorganic oxide particles (specifically, with respect to 100 parts by mass of the total amount of the photocatalyst particles, the inorganic oxide particles, and the hydrolyzable silicone) 1 part by weight and less than 5 parts by weight, preferably 2 parts by weight or more and less than 5 parts by weight, more preferably 2 parts by weight or more and 4.5 parts by weight or less. It is considered that the general contact can be minimized, thereby making it difficult to erode the substrate (particularly the organic substrate). Further, it is considered that the amount of ultraviolet rays reaching the substrate can be reduced by the ultraviolet absorption by the photocatalyst itself, and damage to the substrate due to ultraviolet rays can be reduced.

  At the same time, with this configuration, it is possible to obtain a photocatalyst-coated body excellent in harmful gas decomposability and various desired film properties (transparency, film strength, etc.) while preventing erosion of the substrate (especially organic substrate). It becomes possible. First, since the inorganic oxide particles exceed 85 parts by mass and less than 99 parts by mass, the photocatalyst layer is basically composed of two types of particles, photocatalyst particles and inorganic oxide particles. There are plenty of gaps. When a large amount of hydrolyzable silicone widely used as a binder for the photocatalyst layer is used, it is considered that the gap between the particles is densely filled, and thus gas diffusion is hindered. However, the photocatalyst layer of the present invention does not contain the dried product of hydrolyzable silicone, or even if it contains the dried product of photocatalyst particles, inorganic oxide particles, and dried hydrolyzable silicone, the total amount of silica is 100 parts by mass. On the other hand, since it is less than 10 parts by mass, a gap between particles can be sufficiently maintained and secured, and a structure in which noxious gases such as NOx and SOx easily diffuse into the photocatalyst layer is realized by such a gap, As a result, it is considered that the harmful gas efficiently contacts the photocatalyst particles and is decomposed by the photocatalytic activity. In consideration of the above-described effects, it is most preferable that the amount of the hydrolyzable silicone dried product in terms of silica is substantially 0 part by mass.

  In the above configuration, the photocatalytic decomposition function such as the NOx decomposition function can be exhibited with a small amount of the photocatalyst particles exceeding 1 part by mass and less than 5 parts by mass. Therefore, a photocatalyst-coated body excellent in weather resistance, hydrophilicity, harmful gas decomposability, and various desired coating properties (transparency, film strength, etc.) is realized while preventing erosion of the substrate (especially organic substrate). It is considered to be done. Therefore, the photocatalyst layer according to the present invention has a large amount of ultraviolet rays, particularly in the low latitudes of the tropics and subtropics, and can exhibit excellent durability characteristics at the same time as the photocatalytic decomposition function even under high temperature and high humidity weather conditions.

  The average particle diameter of the photocatalyst particles is preferably 10 nm or more and 100 nm or less, and more preferably 10 nm or more and 60 nm or less. 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 shape of the particle, a true sphere is the best, but it may be approximately circular or elliptical, and the length of the particle in this case is approximately calculated as ((major axis + minor axis) / 2). Within this range, the amount of air flow in the photocatalyst layer, the specific surface area that sufficiently exhibits gas decomposition activity, the single crystal size that the particles exhibit sufficient photocatalytic activity, transparency, and weather resistance are balanced. Well demonstrated. In addition, the average particle diameter of the photocatalyst particles is 10 nm to 100 nm, more preferably 10 nm to 60 nm, which can be suitably combined with each of the constituent elements described so far, and without impeding the effects thereof. It is also possible to exert new effects.

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 , and Fe ₂ O ₃ . Any of the metal oxides exemplified here can be suitably combined with the components described so far.

As photocatalyst particles, titanium oxide particles are preferred. Titanium oxide has better water resistance compared to ZnO. In comparison with SnO _2, it exhibits a photocatalytic function of the gas decomposition with light having a wavelength of 380nm~420nm contained many more sunlight. Furthermore, it is easier to obtain nano-order fine particles than SrTiO _3, and thus it is easy to obtain a practically sufficient photocatalytic activity having a large specific surface area. In addition, the band gap is larger than that of WO ₃ , Bi ₂ O ₃ , and Fe ₂ O ₃ , so that it has sufficient oxidizing power and is difficult to cause recombination of conduction electrons and holes after photoexcitation and is sufficient for gas decomposition. Has a good activation energy. 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.
Utilizing titanium oxide particles as photocatalyst particles can be suitably combined with the components described so far, and can exhibit the above-described new effects without impeding the effects thereof.

As a photocatalyst particle, anatase type titanium oxide is preferable among titanium oxide particles.
Anatase-type titanium oxide has stronger oxidizing power than rutile-type titanium oxide, and more strongly exhibits photocatalytic functions such as gas decomposition. Moreover, the use of anatase-type titanium oxide particles as photocatalyst particles can be suitably combined with each component described so far, and can exhibit the above-described new effect without impeding its effect. it can.

  It is preferable that a Cu component is further present in the photocatalyst layer. Cu itself has excellent antifungal properties, has excellent harmful gas adsorption properties, and acts on the photocatalyst particles to increase the probability of recombination of conduction electrons and holes generated by photoexcitation of the photocatalyst. As a result, the oxidizing power of the photocatalyst particles is improved and the gas decomposition power is increased. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited. In addition, the presence of Cu in the photocatalyst layer can be suitably combined with each component described so far, and the above-described new effect can be exhibited without impeding the effect.

  It is preferable that a Cu component is supported on the photocatalyst particles. In addition to the presence of Cu in the photocatalyst layer, the probability of recombination of conduction electrons and holes generated by photoexcitation of the photocatalyst by Cu acting on the photocatalyst particles by positively supporting Cu on the photocatalyst particles As a result, the oxidizing power of the photocatalyst particles can be improved and the effect of increasing the gas decomposition power can be further enhanced. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited. In addition, positive loading of Cu on the photocatalyst particles can be suitably combined with each of the constituent elements described so far, and the above-described new effect can be exhibited without hindering the effect. .

  It is preferable that both the Cu component and the Ag component exist in the photocatalyst layer. By having both Cu and Ag present in the photocatalyst layer, not only the excellent antifungal properties of Cu and the antibacterial properties of Ag can be exhibited simultaneously, but also the decomposition activity of the photocatalyst is dramatically improved. The mechanism is not clear at present, but probably the interaction between photocatalyst particles, Ag, Cu and the three is related. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited. In addition, the presence of both Cu and Ag in the photocatalyst layer can be suitably combined with each of the constituent elements described so far, and exhibits the above-described new effects without disturbing the effects. Can do.

  It is preferable that both the Cu component and the Ag component are supported on the photocatalyst particles. In addition to the presence of Cu and Ag in the photocatalyst layer, by actively supporting both Cu and Ag on the photocatalyst particles, Cu and Ag act on the photocatalyst particles, and conduction electrons generated by photoexcitation of the photocatalyst The probability of recombination with holes can be reduced, and as a result, the oxidizing power of the photocatalyst particles can be improved and the effect of increasing the gas decomposition power can be further enhanced. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited. In addition, positively supporting both Cu and Ag on the photocatalyst particles can be suitably combined with each component described so far, and exhibits the above-described new effect without disturbing the effect. can do.

Examples of inorganic oxide particles in the photocatalyst layer include silica, alumina, zirconia, ceria, yttria, boronia, magnesia, calcia, ferrite, iron oxide, amorphous titania, hafnia, tin oxide, manganese oxide, niobium oxide, and oxide. Single oxide particles such as nickel, cobalt oxide, indium oxide, lanthanum oxide, and barium oxide, or composite oxides such as aluminosilicate, barium titanate, and calcium silicate can be suitably used.
By blending inorganic oxide particles, while ensuring air permeability in the photocatalyst layer, the amount of photocatalyst can be reduced moderately, and direct contact of the photocatalyst particles with the substrate can be minimized, This is considered to make it difficult to erode a substrate (particularly an organic substrate). Further, it is considered that the amount of ultraviolet rays reaching the substrate can be reduced by the ultraviolet absorption by the photocatalyst itself, and damage to the substrate due to ultraviolet rays can be reduced.
In addition, the use of the inorganic oxide particles can be suitably combined with the constituent elements described so far, and the above-described new effect can be exhibited without impeding the effect.

  Silica is most preferable as the inorganic oxide particles in the photocatalyst layer. By blending silica, the hydrophilicity of the photocatalyst layer is improved, and the photocatalyst layer is washed with water or rainwater, so that it is possible to effectively prevent dirt adhering to the surface from degrading the decomposition function of the photocatalyst. This suppression effect is more significant when the photocatalyst is a photocatalyst that is originally strong in oxidizing power, such as titanium oxide, particularly anatase-type titanium oxide. Moreover, the use of silica particles as the inorganic oxide particles can be suitably combined with each of the constituent elements described so far, and the above-described new effects can be exhibited without impeding the effects.

For the inorganic oxide particles in the photocatalyst layer, the number average particle size calculated by measuring the length of any 100 particles entering the 200,000-fold field of view with a scanning electron microscope is preferably 5 nm or more It is less than 40 nm, more preferably 5 nm or more and less than 20 nm.
By setting the average particle size of the inorganic oxide particles to less than 40 nm, more preferably less than 20 nm, air permeability in the photocatalyst layer is improved, gas decomposition reactivity is improved, and wear resistance is improved.
In addition, the inorganic oxide particles having a number average particle diameter of 5 nm or more and less than 40 nm, more preferably 5 nm or more and less than 20 nm can be suitably combined with each of the components described so far, and The above-described new effect can be exhibited without hindering the effect.

The photocatalyst layer may contain a surfactant as an optional component. The surfactant used in the present invention is contained in the photocatalyst layer as an optional component in an amount of 0 to 10 parts by mass with respect to 100 parts by mass of the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone. Preferably, they are 0 mass part or more and 8 mass parts or less, More preferably, they are 0 or more and 6 mass parts or less. One of the effects of the surfactant is leveling on the base material. For applications that require this leveling effect, such as large-area coating, the surfactant can be used in combination with a coating solution and the base material. The amount may be appropriately determined within the above-mentioned range, but the lower limit at that time is 0.1 parts by mass with respect to 100 parts by mass of the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone. Is preferred. This surfactant is an effective component for improving the wettability of the photocatalyst coating solution, but in the photocatalyst layer formed after coating and drying, it unavoidably contributes to the effect of the photocatalyst-coated body of the present invention. Since it corresponds to an impurity, the upper limit is less than 10 parts by mass, preferably less than 8 parts by mass, more preferably 6 parts by mass with respect to 100 parts by mass of the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone. The following is recommended. 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 not. 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.
In addition, the surfactant used in the present invention is contained in the photocatalyst layer as an optional component with respect to the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone of 100 parts by mass to 0 parts by mass or less. Preferably, the amount is from 0 to 8 parts by weight, and more preferably from 0 to 6 parts by weight, in combination with each of the components described so far. The new effect mentioned above can be exhibited without interfering with the effect.

The photocatalyst layer preferably has a film thickness of 0.5 μm to 3.0 μm, more preferably 1.0 μm to 2.0 μm. By setting the film thickness of the photocatalyst layer to 0.5 μm or more, more preferably 1.0 μm or more, the ultraviolet rays that reach the interface between the photocatalyst layer and the 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, when the film thickness of the photocatalyst layer is 3.0 μm or less, more preferably 2.0 μm or less, excellent characteristics in transparency and film strength can be obtained.
In addition, the film thickness of the photocatalyst layer is 0.5 μm or more and 3.0 μm or less, more preferably 1.0 μm or more and 2.0 μm, which can be suitably combined with each component described so far, and The above-described new effect can be exhibited without hindering the effect.

The photocatalyst layer further contains, as an optional component, a hydrolyzed polycondensation product of titanium alkoxide or a titanium alkoxide derivative in an amount of 0 to 10 parts by mass, preferably 0 to less than 8 parts by mass, more preferably It may contain less than 6 parts by mass.
When the hydrolytic condensation polymer of titanium alkoxide or a derivative of titanium alkoxide is contained in a small amount of less than 10 parts by mass, preferably less than 8 parts by mass, more preferably less than 6 parts by mass in terms of titanium dioxide, the wear resistance is somewhat improved. And compared with hydrolysable silicone, it can be expected that the photocatalyst layer is cured in a shorter time after coating. However, in order to make full use of the excellent photocatalytic gas decomposition properties such as NOx decomposability of the present invention, it is preferable to maintain a sufficient gap between the particles of the photocatalyst layer, but the titanium alkoxide or titanium alkoxide derivatives When a large amount of hydrolyzed polycondensate is used in an amount of 10 parts by mass or more in terms of titanium dioxide, the amount of hydrolyzable silicone widely used as a binder for the photocatalyst layer is similar to that between the particles. It is thought that gas gaps are hindered because the gaps are densely filled. However, the photocatalyst layer of the present invention does not contain titanium alkoxide or a hydrolytic polycondensation product of a titanium alkoxide derivative, or even if it contains a photocatalyst particle, an inorganic oxide particle, and a titanium dioxide equivalent amount of a dried product of titanium alkoxide. Since the total amount is less than 10 parts by mass with respect to 100 parts by mass, the gaps between the particles can be sufficiently maintained and secured, and noxious gases such as NOx and SOx diffuse into the photocatalyst layer through such gaps. It is considered that an easy structure is realized, and as a result, harmful gases come into efficient contact with the photocatalyst particles and are decomposed by the photocatalytic activity.
In consideration of the above-mentioned effects, the more preferable components in this embodiment include titanium dioxide equivalents of titanium alkoxide or titanium alkoxide derivatives, and silica equivalents of hydrolyzable silicone dry matter. And more preferably less than 10 parts by mass, preferably 0 parts by mass to less than 8 parts by mass, more preferably 0 parts by mass to less than 6 parts by mass, and titanium alkoxide or titanium alkoxide. Most preferably, the amount of titanium dioxide in the hydrolyzed condensation polymer of the derivative is substantially 0 part by mass.
In addition, the photocatalyst layer may further include, as an optional component, titanium alkoxide or a photocatalyst layer of titanium alkoxide having a film thickness of a derivative hydrolyzed polycondensate in terms of titanium dioxide of 0 to 10 parts by mass, preferably 0 to 9 parts by mass or more. Less than 8 parts by weight, more preferably less than 6 parts by weight, titanium dioxide equivalent of hydrolyzed polycondensation product of titanium alkoxide or titanium alkoxide derivative, and silica equivalent of dried hydrolyzable silicone The total value with respect to the amount is 0 parts by mass or more and less than 10 parts by mass, preferably 0 parts by mass or more and less than 8 parts by mass, more preferably 0 parts by mass or more and less than 6 parts by mass, and titanium alkoxide or titanium alkoxide. The hydrolytic polycondensation products of these derivatives have substantially 0 part by mass in terms of titanium dioxide. It can be combined with suitably elements, and can exhibit a new effect described above without interfering with their effects.

The photocatalyst layer is preferably obtained by heat drying at 200 ° C. or lower. By doing so, when the base material is a resin, deterioration due to heating of the base material can be effectively prevented.
Note that the photocatalyst layer can be obtained by heating and drying at 200 ° C. or less, which can be suitably combined with each of the components described so far, and exhibits the above-described new effect without impeding its effect. can do.

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.
It should be noted that the hydrolyzable silicone is an organosiloxane having at least one reactive group selected from the group consisting of an alkoxy group, a halogen group and a hydrogen group, preferably as a hydrolyzable silicone, preferably as a monomer unit thereof. A bifunctional silane, a trifunctional silane, a tetrafunctional silane is polymerized alone or in combination, and a silicone (oligomer or polymer) having a reactive group at its terminal is used, and more preferably a tetrafunctional silicone is used. About utilization, it can combine suitably with each component described so far, and can demonstrate the new effect mentioned above, without preventing the effect.

The hydrolyzable silicone is more preferably an organosiloxane having an alkoxy group. The organosiloxane having an alkoxy group is easier to control the dehydration condensation polymerization reaction than the organosiloxane having a halogen group or a hydrogen group, and a stable quality photocatalyst layer is easily obtained.
In addition, making hydrolysable silicone an organosiloxane having an alkoxy group can be suitably combined with each component described so far, and the new effect described above without disturbing the effect. Can be demonstrated.

The dried hydrolyzable silicone is more preferably a hydrolyzed polycondensate of hydrolyzable silicone.
The hydrolytic condensation polymerization reaction is easier to control than other radical polymerization reactions and the like, and it becomes easier to obtain a stable photocatalyst layer.
It should be noted that the dried hydrolyzable silicone product is a hydrolyzable polycondensate of hydrolyzable silicone, which can be suitably combined with each of the components described so far and hinders its effect. The above-described new effect can be exhibited.

The base material used in the present invention may be various materials regardless of whether it is an inorganic material or an organic material as long as it can form a photocatalyst layer thereon, and its shape is not limited. Preferred examples of the substrate from the viewpoint of materials include metals, ceramics, glass, plastics, rubber, stones, cement, concrete, fibers, fabrics, wood, paper, combinations thereof, laminates thereof, Examples thereof include those having at least one layer of coating on the surface.
Any of these substrates can be suitably combined with the components described so far.

In particular, when a base material having at least a surface thereof formed of an organic material is used as the base material, the characteristics of the present invention can be sufficiently exhibited. Here, as the base material whose surface is formed of an organic material, the whole base material is composed of an organic material, or the base material composed of an inorganic material is coated with an organic material (for example, makeup) Plate). According to the photocatalyst layer of the present invention, an organic material that is easily damaged by photocatalytic activity is less likely to erode, so that an excellent function can be achieved in one layer called a photocatalyst layer without interposing an intermediate layer made of an inorganic material. The photocatalyst coating body which has can be manufactured. As a result, the time required for manufacturing the photocatalyst-coated body can be reduced because the formation of the intermediate layer made of an inorganic material becomes unnecessary, and the productivity can be improved and the cost can be reduced.
Note that the use of a base material having at least a surface formed of an organic material as the base material can be suitably combined with each of the constituent elements described so far, and the above-described new features can be achieved without hindering the effect. The effect can be demonstrated.

Even in a usage form in which the photocatalyst layer is directly applied on the substrate, the characteristics of the present invention can be more fully exhibited. This is because the photocatalyst layer of the present invention is mainly composed of particles, and therefore has excellent followability with respect to the unevenness of the substrate.
The usage pattern in which the photocatalyst layer is directly applied on the substrate can be suitably combined with each of the components described so far, and exhibits the above-described new effects without disturbing the effects. can do.

It is also preferable to provide an intermediate layer between the substrate and the photocatalyst layer. In particular, if a substance having excellent weather resistance is used as the intermediate layer, the weather resistance when the substrate 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, even if the base material has irregularities, it is difficult to cause appearance defects due to cracks during use. 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.
It should be noted that an intermediate layer is provided between the substrate and the photocatalyst layer, a substance having excellent weather resistance is used as the intermediate layer, and substances having excellent weather resistance include silicone-containing resins and fluorine-containing resins. Using at least one of them, using a material having excellent flexibility for the intermediate layer, and a material having excellent flexibility include a resin having a double chain structure, a resin having a cyclic structure, and a bifunctional monomer The use of at least one of silicone containing units and silicone containing both organic and inorganic crosslinks can be suitably combined with each of the components described so far and does not interfere with its effects. New effects can be exhibited.

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.
As the silicone-modified resin, a silicone-modified acrylic resin, a silicone-modified epoxy resin, a silicone-modified urethane resin, a silicone-modified polyester and the like containing polysiloxane in the resin are more preferable from the viewpoint of weather resistance.
In the silicone-modified resin, the silicon atom content is preferably 0.2% by mass or more and less than 16.5% by mass, more preferably 6.5% by mass or more and less than 16.5% by mass, based on the solid content of the silicone-modified resin. It is. When the silicon atom content contained in the silicone-modified resin is 0.2% by mass or more, the weather resistance of the intermediate layer is improved and the possibility of being eroded by the photocatalyst is suppressed. Moreover, when the silicon atom content contained in the silicone-modified resin is less than 16.5% by mass, the flexibility is sufficient and the generation of cracks in the intermediate layer is suppressed. Here, the silicon atom content in the silicone-modified resin can be measured by chemical analysis using an X-ray photoelectron spectrometer (XPS).
As acrylic silicon, it is more preferable to use a mixture of two liquids of a silicone-modified acrylic resin having a carboxyl group and a silicone resin having an epoxy group from the viewpoint of improving the strength of the coating film.
Although the dry film thickness of an intermediate | middle layer is not specifically limited, Preferably they are 1 micrometer-50 micrometers, More preferably, they are 1 micrometer-10 micrometers. If the thickness is less than 1 μm, the effect of suppressing degradation of the intermediate layer and the substrate by the photocatalyst may be inferior. When it is thicker than 50 μm, although it depends on the type of the intermediate layer, there is a possibility that fine cracks may occur after drying.
The intermediate layer comprises a silicone-modified resin. As the silicone-modified resin, the silicon atom content is preferably 0.2% by mass or more and less than 16.5% by mass with respect to the solid content of the silicone-modified resin. Is 6.5 mass% or more and less than 16.5 mass%, the intermediate layer comprises acrylic silicon, and acrylic silicone is a two-part solution of a silicone-modified acrylic resin having a carboxyl group and a silicone resin having an epoxy group. Can be suitably combined with each of the components described so far, and preferably the dry film thickness of the intermediate layer is preferably 1 μm to 50 μm, more preferably 1 μm to 10 μm, And the new effect mentioned above can be exhibited, without disturbing the effect.

The intermediate layer preferably comprises a UV absorber. By doing so, the weather resistance of a base material and the durability with respect to a photocatalytic reaction can be increased further.
In addition, it can combine suitably with each component described so far that an intermediate | middle layer contains a ultraviolet absorber, and can demonstrate the new effect mentioned above, without preventing the effect.

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.
The intermediate layer containing the organic antifungal agent can be suitably combined with each of the constituent elements described so far, and can exhibit the above-described new effect without impeding its effect. .

In addition to the above, the intermediate layer may contain organic solvents, coloring pigments, extender pigments, pigment dispersants, antifoaming agents, additives for coatings such as antioxidants, and other components usually contained in coatings. Further, silica fine particles may be included as a matting agent.
The color pigment is not particularly limited, and examples thereof include inorganic pigments such as titanium dioxide, iron oxide, and carbon black, phthalocyanine series, benzimidazolone series, isoindolinone series, azo series, anthraquinone series, quinophthalone series, anthra Organic pigments such as pyridinin, quinacridone, toluidine, pyrathrone, and perylene can be used.

Although the coated body of the present invention can be applied to both exterior and interior materials, it is particularly preferable to use it as an exterior material because sunlight can be used as a light source for the photocatalyst. Here, as exterior materials, building materials, building exteriors, window frames, window glass, structural members, exterior and painting of vehicles, exteriors of machinery and articles, dust covers and paintings, traffic signs, various display devices, advertising towers, Sound insulation walls for roads, sound insulation walls for railways, bridges, guard rail exteriors and paintings, tunnel interiors and paintings, insulators, solar cell covers, solar water heater heat collection covers, plastic houses, vehicle lighting cover, outdoor lighting fixtures And a film, a sheet, a seal and the like for adhering to the table and the surface of the article.
In addition, using a coating body as an exterior material can combine suitably with each component described so far, and can exhibit the new effect mentioned above, without preventing the effect.

  Further, at least one metal selected from the group consisting of vanadium, iron, cobalt, nickel, manganese, palladium, zinc, ruthenium, rhodium, platinum and gold and / or a metal compound consisting of the metal is added to the photocatalyst layer. May be. Thereby, the catalytic function of these metals can be expressed simultaneously.

Photocatalyst coating liquid The photocatalyst coating liquid according to the present invention is a coating liquid for forming the photocatalyst-coated body as described above, and includes a solvent and 1 to 5 parts by mass of 10 to 100 nm. The photocatalyst particles having an average particle size of, the inorganic oxide particles of more than 85 parts by mass and 99 parts by mass or less, and the hydrolyzable silicone of 0 parts by mass or more and less than 10 parts by mass in terms of silica, The total amount of the inorganic oxide particles and the hydrolyzable silicone in terms of silica is 100 parts by mass.
That is, when a photocatalyst coating liquid is applied to a substrate and dried to form a photocatalyst layer, the proportion of photocatalyst particles is considerably less than that of inorganic oxide particles (specifically, photocatalyst particles, inorganic oxide particles , And a total amount of hydrolyzable silicone of 100 parts by mass, more than 1 part by mass and less than 5 parts by mass, preferably 2 parts by mass or more and less than 5 parts by mass, more preferably 2 parts by mass or more and 4.5 parts by mass. It is considered that the direct contact of the photocatalyst particles with the base material can be minimized, thereby making it difficult for the base material (especially the organic base material) to be eroded. Further, it is considered that the amount of ultraviolet rays reaching the substrate can be reduced by the ultraviolet absorption by the photocatalyst itself, and damage to the substrate due to ultraviolet rays can be reduced.

At the same time, with this configuration, it is possible to obtain a photocatalyst-coated body excellent in harmful gas decomposability and various desired film properties (transparency, film strength, etc.) while preventing erosion of the substrate (especially organic substrate). It becomes possible. First, since the photocatalyst layer is basically composed of two types of particles, photocatalyst particles and inorganic oxide particles, there are abundant gaps between the particles, but hydrolyzable silicone widely used as a binder for the photocatalyst layer. When a large amount of is used, the gaps between the particles are densely filled, which is considered to hinder gas diffusion. However, the photocatalyst layer of the present invention does not contain a hydrolyzable silicone dry matter, or even if it contains photocatalyst particles,
Since the silica equivalent amount of the inorganic oxide particles and the hydrolyzable silicone dry matter is less than 10 parts by mass with respect to the total amount of 100 parts by mass, the gap between the particles can be sufficiently maintained and secured. Such a gap realizes a structure in which harmful gases such as NOx and SOx are easily diffused into the photocatalyst layer, and as a result, it is considered that the harmful gases are efficiently contacted with the photocatalyst particles and decomposed by the photocatalytic activity. . In consideration of the above-described effects, it is most preferable that the amount of the hydrolyzable silicone dried product in terms of silica is substantially 0 part by mass.

  In the above configuration, the photocatalytic decomposition function such as the NOx decomposition function can be exhibited with a small amount of the photocatalyst particles exceeding 1 part by mass and less than 5 parts by mass. Therefore, a photocatalyst-coated body excellent in weather resistance, hydrophilicity, harmful gas decomposability, and various desired coating properties (transparency, film strength, etc.) is realized while preventing erosion of the substrate (especially organic substrate). It is considered to be done. Therefore, the photocatalyst layer according to the present invention has a large amount of ultraviolet rays, particularly in the low latitudes of the tropics and subtropics, and can exhibit excellent durability characteristics at the same time as the photocatalytic decomposition function even under high temperature and high humidity weather conditions.

  The average particle diameter of the photocatalyst particles in the photocatalyst coating liquid is preferably 10 nm or more and 100 nm or less, and more preferably 10 nm or more and 60 nm or less. 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 shape of the particle, a true sphere is the best, but it may be approximately circular or elliptical, and the length of the particle in this case is approximately calculated as ((major axis + minor axis) / 2). Within this range, the amount of air flow in the photocatalyst layer formed by applying and drying the photocatalyst coating liquid on the substrate, the specific surface area amount that sufficiently exhibits the gas decomposition activity, and the particles that exhibit sufficient photocatalytic activity. Various film properties such as crystal size, transparency and weather resistance are exhibited in a well-balanced manner. In addition, the average particle diameter of the photocatalyst particles is 10 nm to 100 nm, more preferably 10 nm to 60 nm, which can be suitably combined with each of the constituent elements described so far, and without impeding the effects thereof. It is also possible to exert new effects.

Examples of the photocatalyst particles in the photocatalyst coating liquid include metal oxide particles such as titanium oxide (TiO ₂ ), ZnO, SnO ₂ , SrTiO ₃ , WO ₃ , Bi ₂ O ₃ , and Fe ₂ O _3. . Any of the metal oxides exemplified here can be suitably combined with the components described so far.

The photocatalyst particles in the photocatalyst coating liquid are preferably titanium oxide particles. Titanium oxide has better water resistance compared to ZnO. In comparison with SnO _2, it exhibits a photocatalytic function of the gas decomposition with light having a wavelength of 380nm~420nm contained many more sunlight. Furthermore, it is easier to obtain nano-order fine particles than SrTiO _3, and thus it is easy to obtain a practically sufficient photocatalytic activity having a large specific surface area. In addition, the band gap is larger than that of WO ₃ , Bi ₂ O ₃ , and Fe ₂ O ₃ , so that it has sufficient oxidizing power and is difficult to cause recombination of conduction electrons and holes after photoexcitation and is sufficient for gas decomposition. Has a good activation energy. 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 that shows photocatalytic activity after coating and drying on a substrate can be used in the coating solution. It is also possible to mix them.
The use of titanium oxide particles as photocatalyst particles can be suitably combined with the constituent elements described so far, and can exhibit the above-described new effects without hindering the effects.

  As a photocatalyst particle in a photocatalyst coating liquid, anatase type titanium oxide is preferable among titanium oxide particles. Anatase-type titanium oxide has stronger oxidizing power than rutile-type titanium oxide, and more strongly exhibits photocatalytic functions such as gas decomposition. Moreover, the use of anatase-type titanium oxide particles as photocatalyst particles can be suitably combined with each component described so far, and can exhibit the above-described new effect without impeding its effect. it can.

It is preferable to further mix a Cu component in the photocatalyst coating liquid. Cu itself has excellent antifungal properties, has excellent harmful gas adsorption properties, and acts on the photocatalyst particles to increase the probability of recombination of conduction electrons and holes generated by photoexcitation of the photocatalyst. As a result, the oxidizing power of the photocatalyst particles is improved and the gas decomposition power is increased. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited.
In addition, the incorporation of the Cu component in the photocatalyst coating liquid can be suitably combined with each of the constituent elements described so far, and can exhibit the above-described new effect without hindering the effect. .

  It is preferable that a Cu component is supported on the photocatalyst particles in the photocatalyst coating liquid. Not only simply adding the Cu component, but also actively supporting Cu on the photocatalyst particles, reducing the probability of recombination of conduction electrons and holes generated by photoexcitation of the photocatalyst by Cu acting on the photocatalyst particles. As a result, the effect of increasing the gas decomposing power by improving the oxidizing power of the photocatalyst particles can be further enhanced. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited. In addition, positive loading of Cu on the photocatalyst particles can be suitably combined with each of the constituent elements described so far, and the above-described new effect can be exhibited without hindering the effect. .

  It is preferable to mix both the Cu component and the Ag component in the photocatalyst coating liquid. By blending both Cu and Ag in the photocatalyst coating liquid, not only the excellent antifungal properties of Cu and the antibacterial properties of Ag can be exhibited simultaneously, but also the decomposition activity of the photocatalyst is dramatically improved. The mechanism is not clear at present, but probably the interaction between photocatalyst particles, Ag, Cu and the three is related. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited. In addition, the incorporation of both the Cu component and the Ag component in the photocatalyst coating liquid can be suitably combined with each component described so far, and the above-described new effect can be obtained without disturbing the effect. It can be demonstrated.

  It is preferable that both the Cu component and the Ag component are supported on the photocatalyst particles in the photocatalyst coating liquid. In addition to the presence of Cu and Ag in the photocatalyst coating liquid, by actively loading both Cu and Ag on the photocatalyst particles, Cu and Ag act on the photocatalyst particles and are generated by photoexcitation of the photocatalyst. The effect of increasing the gas decomposition power can be further enhanced by reducing the probability of recombination of electrons and holes and consequently improving the oxidizing power of the photocatalyst particles. Here, when the photocatalyst is a photocatalyst having a strong oxidizing power such as titanium oxide, particularly anatase type titanium oxide, a greater effect is exhibited. In addition, positively supporting both Cu and Ag on the photocatalyst particles can be suitably combined with each component described so far, and exhibits the above-described new effect without disturbing the effect. can do.

Examples of the inorganic oxide particles in the photocatalyst coating solution include silica, alumina, zirconia, ceria, yttria, boronia, magnesia, calcia, ferrite, iron oxide, amorphous titania, hafnia, tin oxide, manganese oxide, niobium oxide, Single oxide particles such as nickel oxide, cobalt oxide, indium oxide, lanthanum oxide, and barium oxide, or composite oxides such as aluminosilicate, barium titanate, and calcium silicate can be suitably used. These inorganic oxide particles are preferably blended in the form of an aqueous colloid using water as a dispersion medium; or an organosol dispersed colloidally in a hydrophilic solvent such as ethyl alcohol, isopropyl alcohol, or ethylene glycol.
By blending the inorganic oxide particles in the photocatalyst coating liquid, the amount of the photocatalyst is moderately reduced while ensuring the air permeability in the photocatalyst layer obtained by applying and drying the photocatalyst coating liquid, and the base of the photocatalyst particles. It is believed that direct contact with the material can be minimized, thereby making it less likely to erode the substrate (especially the organic substrate). Further, it is considered that the amount of ultraviolet rays reaching the substrate can be reduced by the ultraviolet absorption by the photocatalyst itself, and damage to the substrate due to ultraviolet rays can be reduced.

  Silica is most preferred as the inorganic oxide particles in the photocatalyst coating liquid. By blending silica, the hydrophilicity of the photocatalyst layer is improved, and the photocatalyst layer is washed with water or rainwater, so that it is possible to effectively prevent dirt adhering to the surface from degrading the decomposition function of the photocatalyst. This suppression effect is more significant when the photocatalyst is a photocatalyst that is originally strong in oxidizing power, such as titanium oxide, particularly anatase-type titanium oxide. The silica particles are preferably in the form of an aqueous colloid using water as a dispersion medium; or an organosol dispersed colloidally in a hydrophilic solvent such as ethyl alcohol, isopropyl alcohol, or ethylene glycol, and particularly preferably colloidal silica. is there. Moreover, the use of silica particles as the inorganic oxide particles can be suitably combined with each of the constituent elements described so far, and the above-described new effects can be exhibited without impeding the effects.

For the inorganic oxide particles in the photocatalyst coating liquid, the number average particle diameter calculated by measuring the length of any 100 particles entering a 200,000-fold field of view with a scanning electron microscope is preferably 5 nm. It is more than 40 nm, more preferably 5 nm or more and less than 20 nm.
By making the average particle size of the inorganic oxide particles less than 40 nm, more preferably less than 20 nm, the air permeability in the photocatalyst layer obtained when the photocatalyst coating liquid is applied to the substrate and dried is improved, and the gas decomposition The reactivity is improved and the wear resistance is improved.
In addition, the inorganic oxide particles in the photocatalyst coating liquid preferably have a number average particle diameter of 5 nm or more and less than 40 nm, more preferably 5 nm or more and less than 20 nm, in combination with each component described so far. And the above-described new effect can be exhibited without hindering the effect.

The photocatalyst coating liquid may contain a surfactant as an optional component. The surfactant used in the present invention is contained in the photocatalyst layer as an optional component in an amount of 0 to 10 parts by mass with respect to 100 parts by mass of the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone. Preferably, they are 0 mass part or more and 8 mass parts or less, More preferably, they are 0 or more and 6 mass parts or less. One of the effects of the surfactant is leveling on the base material. For applications that require this leveling effect, such as large-area coating, the surfactant can be used in combination with a coating solution and the base material. The amount may be appropriately determined within the above-mentioned range, but the lower limit at that time is 0.1 parts by mass with respect to 100 parts by mass of the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone. Is preferred. This surfactant is an effective component for improving the wettability of the photocatalyst coating solution, but in the photocatalyst layer formed after coating and drying, it unavoidably contributes to the effect of the photocatalyst-coated body of the present invention. Since it corresponds to an impurity, the upper limit is less than 10 parts by mass, preferably less than 8 parts by mass, more preferably 6 parts by mass with respect to 100 parts by mass of the total amount of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone. The following is recommended. 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 not. 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.
In addition, the surfactant used in the coating liquid of the present invention is, as an optional component, a photocatalyst of 0 to 10 parts by mass with respect to 100 parts by mass as a total of photocatalyst particles, inorganic oxide particles, and hydrolyzable silicone. It may be contained in the layer, preferably 0 to 8 parts by mass, more preferably 0 to 6 parts by mass, suitably with each component described so far The above-described new effects can be exhibited without interfering with the effects.

The photocatalyst coating liquid further contains, as an optional component, a hydrolytic polycondensation product of titanium alkoxide or a titanium alkoxide derivative in an amount of 0 to 10 parts by mass, preferably 0 to less than 8 parts by mass, more preferably, in terms of titanium dioxide. May contain less than 6 parts by mass.
When the hydrolytic condensation polymer of titanium alkoxide or a derivative of titanium alkoxide is contained in a small amount of less than 10 parts by mass, preferably less than 8 parts by mass, more preferably less than 6 parts by mass in terms of titanium dioxide, the wear resistance is somewhat improved. And compared with hydrolysable silicone, it can be expected that the photocatalyst layer is cured in a shorter time after coating. However, in order to make full use of the excellent photocatalytic gas decomposition characteristics such as NOx decomposability of the present invention, it is preferable to maintain a sufficient gap between the particles of the photocatalyst layer. However, titanium alkoxide or a derivative of titanium alkoxide is preferable. When a large amount of hydrolyzed polycondensate is used in an amount of 10 parts by mass or more in terms of titanium dioxide, the amount of hydrolyzable silicone widely used as a binder for the photocatalyst layer is similar to that between the particles. It is thought that gas gaps are hindered because the gaps are densely filled. However, the photocatalyst coating liquid of the present invention does not contain or contains a hydrolysis-condensation polymer of titanium alkoxide or a derivative of titanium alkoxide, and even if it contains, photocatalyst particles, inorganic oxide particles, and titanium dioxide equivalent amount of dried titanium alkoxide Since the total amount is less than 10 parts by mass with respect to 100 parts by mass, the gaps between the particles can be sufficiently maintained and secured, and harmful gases such as NOx and SOx diffuse into the photocatalyst layer through such gaps. As a result, it is considered that the harmful gas is efficiently brought into contact with the photocatalyst particles and decomposed by the photocatalytic activity.
In view of the above-described effects, the more preferable configuration in this embodiment includes titanium dioxide equivalent amount of hydrolyzed polycondensation product of titanium alkoxide or titanium alkoxide derivative, and silica equivalent amount of dried hydrolyzable silicone. Is more than 0 parts by weight and less than 10 parts by weight, preferably 0 parts by weight and less than 8 parts by weight, more preferably 0 parts by weight and less than 6 parts by weight. Titanium alkoxide or titanium alkoxide derivative It is most preferable that the amount of titanium dioxide in the hydrolyzed polycondensation product is substantially 0 part by mass.
In addition, the photocatalyst coating liquid further contains, as an optional component, titanium alkoxide or a photocatalytic layer of titanium alkoxide having a film thickness of a hydrolysis-condensation polymer derived from a derivative of 0 to 10 parts by mass, preferably 0 parts by mass in terms of titanium dioxide. More than 8 parts by mass, more preferably less than 6 parts by mass, titanium dioxide equivalent amount of hydrolyzed polycondensation product of titanium alkoxide or titanium alkoxide derivative, and silica of dried hydrolyzable silicone The total value with the converted amount is 0 parts by mass or more and less than 10 parts by mass, preferably 0 parts by mass or more and less than 8 parts by mass, more preferably 0 parts by mass or more and less than 6 parts by mass, and titanium alkoxide or titanium. The fact that the amount of titanium dioxide in the hydrolyzed polycondensation product of the alkoxide derivative is substantially 0 part by mass is heretofore. It mentioned respective components and suitably it can be combined with and, and can exhibit a new effect described above without interfering with their effects.

The hydrolyzable silicone, which is an optional component in the photocatalyst coating solution, is preferably an organosiloxane having at least one reactive group selected from the group of alkoxy groups, halogen groups, and hydrogen groups.
These hydrolyzable silicones are cured at room temperature after being applied to a substrate 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. Can be improved.
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 hydrolyzable silicone, which is an optional component in the photocatalyst coating solution, should be an organosiloxane having at least one reactive group selected from the group of alkoxy groups, halogen groups, and hydrogen groups, hydrolyzable Utilizing a silicone (oligomer, polymer) having a reactive group at its terminal, preferably by polymerizing a bifunctional silane, a trifunctional silane, or a tetrafunctional silane alone or in combination as a monomer unit as a silicone, And more preferably, the use of the tetrafunctional silicone can be suitably combined with each component described so far, and the above-described new effect can be exhibited without hindering the effect.

The hydrolyzable silicone that is an optional component in the photocatalyst coating liquid is more preferably an organosiloxane having an alkoxy group. The organosiloxane having an alkoxy group is easier to control the dehydration condensation polymerization reaction than the organosiloxane having a halogen group or a hydrogen group, and a stable quality photocatalyst layer is easily obtained.
It should be noted that the hydrolyzable silicone, which is an optional component in the photocatalyst coating solution, can be suitably combined with each component described so far, and the effect thereof, so that it is an organosiloxane having an alkoxy group. The above-described new effect can be exhibited without hindering.

  Furthermore, at least one metal selected from the group consisting of vanadium, iron, cobalt, nickel, manganese, palladium, zinc, ruthenium, rhodium, platinum and gold and / or a metal compound consisting of the metal is added to the photocatalyst coating solution. May be. Thereby, the catalytic function of these metals can be expressed simultaneously. This addition can be performed by any method such as a method in which the metal or metal compound is mixed and dissolved or dispersed in a coating solution, or a method in which the metal or metal compound is supported on a photocatalyst layer or photocatalyst particles.

As a solvent in the photocatalyst coating liquid, water or an organic solvent can be used, but water is preferable. By doing so, since a coating film can be formed without volatilizing an organic solvent at the time of coating, it is environmentally preferable. Moreover, the solid content concentration of the photocatalyst coating liquid of the present invention is not particularly limited, but it is preferably 1 to 10% 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.
Note that the solvent in the photocatalyst coating liquid is water, and the solid content concentration of the photocatalyst coating liquid is 1 to 10% by mass, and can be suitably combined with each component described so far, and The above-described new effect can be exhibited without hindering the effect.

Among the photocatalyst-coated bodies described above, the intermediate layer-forming coating liquid for forming the photocatalyst-coated body on which the intermediate layer is formed preferably contains a solvent and a silicone-modified resin, and more preferably the solvent and acrylic silicon. Is preferably included.
By doing so, the weather resistance of the intermediate layer, durability against the photocatalytic reaction, flexibility and the like can be sufficiently exhibited.
As the silicone-modified resin, a silicone-modified acrylic resin, a silicone-modified epoxy resin, a silicone-modified urethane resin, a silicone-modified polyester, etc. containing polysiloxane in the resin are more preferable from the viewpoint of weather resistance.
In the silicone-modified resin, the silicon atom content is preferably 0.2% by mass or more and less than 16.5% by mass, more preferably 6.5% by mass or more and less than 16.5% by mass, based on the solid content of the silicone-modified resin. It is. When the silicon atom content contained in the silicone-modified resin is 0.2% by mass or more, the weather resistance of the intermediate layer is improved and the possibility of being eroded by the photocatalyst is suppressed. Moreover, when the silicon atom content contained in the silicone-modified resin is less than 16.5% by mass, the flexibility is sufficient and the generation of cracks in the intermediate layer is suppressed. Here, the silicon atom content in the silicone-modified resin can be measured by chemical analysis using an X-ray photoelectron spectrometer (XPS).
As acrylic silicon, it is more preferable to use a mixture of two liquids of a silicone-modified acrylic resin having a carboxyl group and a silicone resin having an epoxy group from the viewpoint of improving the strength of the coating film.
The intermediate layer comprises a silicone-modified resin. As the silicone-modified resin, the silicon atom content is preferably 0.2% by mass or more and less than 16.5% by mass with respect to the solid content of the silicone-modified resin. Is 6.5 mass% or more and less than 16.5 mass%, the intermediate layer comprises acrylic silicon, and acrylic silicone is a two-part solution of a silicone-modified acrylic resin having a carboxyl group and a silicone resin having an epoxy group. It is preferable to use a mixture of these components, which can be suitably combined with the components described so far, and the above-described new effects can be exhibited without impeding the effects.
It should be noted that the intermediate layer forming coating solution contains a solvent and a silicone-modified resin, and the intermediate layer forming coating solution contains a solvent and acrylic silicon are suitably combined with the components described so far. And the above-described new effect can be exhibited without hindering the effect.

Of the above-described photocatalyst-coated bodies, the intermediate layer-forming coating liquid for forming the photocatalyst-coated body on which the intermediate layer is formed preferably contains an ultraviolet absorber. By doing so, the weather resistance of a base material and the durability with respect to a photocatalytic reaction can be increased further.
In addition, that the coating liquid for forming an intermediate layer contains an ultraviolet absorber can be suitably combined with each of the constituent elements described so far, and exhibits the above-described new effect without hindering the effect. be able to.

Of the above-described photocatalyst-coated bodies, the intermediate layer-forming coating liquid for forming the photocatalyst-coated body on which the intermediate layer is formed preferably contains an organic antifungal agent. An organic antifungal agent is contained in an intermediate layer different from the photocatalyst layer, and a gap is provided between the particles of the photocatalyst layer. The anti-algae and anti-fungal functions can be effectively demonstrated without damaging each other.
In addition, the fact that the coating liquid for forming an intermediate layer contains an organic antifungal agent can be suitably combined with each of the components described so far, and exhibits the above-described new effect without impeding its effect. can do.

As a solvent in the coating liquid for forming an intermediate layer, water or an organic solvent can be used, but water is preferable. By doing so, since a coating film can be formed without volatilizing an organic solvent at the time of coating, it is environmentally preferable.
The solid content concentration of the intermediate layer coating solution of the present invention is not particularly limited, but it is preferably 10 to 20% by mass in terms of easy application. In addition, the analysis of the structural component in an intermediate | middle layer coating liquid can be evaluated by infrared spectroscopy about a resin component.
In addition, it is preferable with each component described so far that the solvent in the coating liquid for forming the intermediate layer is water, and that the solid content concentration of the liquid agent for coating an intermediate layer of the present invention is preferably 10 to 20% by mass. The above-described new effects can be exhibited without interfering with the effects.

Photocatalyst layer manufacturing method The photocatalyst coating body of this invention can be easily manufactured by apply | coating the photocatalyst coating liquid of this invention on a base material. 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, and screen printing can be used. After applying the coating liquid to the substrate, it may be dried at room temperature, or may be heat-dried as necessary, but when heated until 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 base material. When the resin is contained in at least a part of the substrate, the preferable drying temperature is 10 ° C. or higher and 200 ° C. or lower in consideration of the heat-resistant temperature of the resin.

Intermediate Layer Manufacturing Method The intermediate layer coated body of the present invention can be easily manufactured by applying the intermediate layer coating liquid of the present invention onto the substrate. As a method for coating the intermediate 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 applying the coating liquid to the substrate, it may be dried at room temperature, or may be heat-dried as necessary.

<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 water dispersion (average particle size: 42 nm, basic)
Inorganic oxide particles / water-dispersed colloidal silica (average particle size: 14 nm, basic) (used in Examples 1 to 7, Example 9 and Examples 11 to 23)
Water-dispersed colloidal silica (average particle size: 26 nm, basic) (used in Example 8)
Water-dispersed colloidal silica (average particle size: 5 nm, basic) (used in Example 10)
Hydrocondensable silicone / tetramethoxysilane polycondensate (SiO ₂ equivalent concentration: 51 mass%, solvent: methanol, water)
Surfactant / polyether-modified silicone surfactant

Examples 1-3: Evaluation of weather resistance (exposure outdoors)
The photocatalyst coating body provided with the photocatalyst layer was manufactured as follows. First, a colored organic coated body was prepared as a base material. This colored organic coated body is obtained by applying general-purpose acrylic silicone to which carbon black powder is added on a sealer-treated ceramic siding base material, followed by sufficient drying and curing. 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 surfactant are mixed at a compounding ratio shown in Table 1 to obtain a photocatalyst coating liquid. It was. 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 in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. 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 3.

  The photocatalyst-coated body having a size of 50 × 100 mm obtained in this way was exposed outdoors at an angle of 20 ° from the horizontal toward the south surface in Miyakojima using an exposure stand defined in JIS K 5600-7-6. . The appearance was visually confirmed every three months.

  The obtained results were as shown in Table 1. Here, “G” in the table shows almost no change, and “NG” shows that white bloom slightly occurs. As shown in Table 1, it was found that the photocatalyst particle content in the photocatalyst layer is less than 5 parts by mass, so that the photocatalyst layer has sufficient weather resistance even if the photocatalyst layer is coated on the organic substrate in Miyakojima. It was.

Examples 4 to 6: Evaluation of hydrophilicity by exposure to ultraviolet rays A photocatalyst-coated body provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a base material. 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 having various average particle diameters shown in Table 2, water as a solvent, and a surfactant are shown in Table 2. To obtain a photocatalyst coating solution. 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 in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. 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 4 to 6.

The photocatalyst-coated body thus obtained was evaluated for hydrophilicity as follows. After curing the photocatalyst-coated body in a dark place for 1 day, the photocatalyst-coated surface is left for 7 days under BLB light adjusted to 1 mW / cm ^2, and the contact angle of the photocatalyst-coated surface is measured with a contact angle meter (Kyowa Interface) It was measured by Kagaku CA-X150 type). The contact angle was measured using a hydrophilic substitute.

The obtained results were as shown in Table 2. Here, the evaluation criteria for the hydrophilicity to UV exposure were as follows.
<Hydrophilicity>
A: Contact angle is less than 10 ° B: Contact angle is not less than 10 ° and less than 20 ° C: Contact angle is not less than 20 ° As shown in Table 2, the content of the photocatalyst particles in the photocatalyst layer is not less than 2 parts by mass. It was found that high hydrophilicity was ensured.

Examples 7 and 8: Evaluation of sliding wear resistance A photocatalyst-coated body provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a base material. This colored organic coated body is obtained by applying general-purpose acrylic silicone added with carbon black powder to a slate plate treated with an epoxy resin 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 having various average particle diameters shown in Table 3, water as a solvent, and a surfactant are shown in Table 3. To obtain a photocatalyst coating solution. 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 in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. 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 7 and 8.

  The photocatalyst-coated body thus obtained was subjected to a washing resistance test as follows. The test method was performed according to JIS A6909. The photocatalyst-coated body was fixed horizontally on a test stand of a cleaning tester (No. 458 Washability Tester manufactured by Toyo Seiki Seisakusho) with the photocatalyst-coated surface facing upward. The tip of a pork brush with a dry brush weight of 450 g was immersed in a 0.5% solution of soapy water, placed on the photocatalyst coating surface, reciprocated 500 times, then removed, washed with water and dried.

The well-dried photocatalyst-coated body was irradiated with BLB light adjusted to 3 mW / cm ² for 24 hours, and then the contact angle of the photocatalyst-coated surface was measured with a contact angle meter (CA-X150 manufactured by Kyowa Interface Science). The contact angle was measured using a hydrophilic substitute.

The obtained results were as shown in Table 3. Here, the evaluation criteria of the sliding wear resistance were as follows.
<Sliding wear resistance>
A: Contact angle is less than 10 ° B: Contact angle is 10 ° or more As shown in Table 3, the photocatalyst-coated body of Example 7 was found to form a strong film against sliding.

Examples 9 and 10: Measurement of haze A photocatalyst-coated body 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 substrate. On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide having various average particle diameters shown in Table 4, water as a solvent, and a surfactant are shown in Table 4. To obtain a photocatalyst coating solution. 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 spin-coated on the above-mentioned substrate at 1000 rpm for 10 seconds and dried at 120 ° C. to obtain a photocatalyst layer. The haze of the photocatalyst-coated body having a size of 50 × 100 mm obtained in this manner was measured using a haze meter (haze-gard plus from Gardner).

  The obtained results were as shown in Table 4. It turned out that the photocatalyst coating body of Example 9 can suppress a haze value to less than 1%, and can ensure transparency.

Examples 11 to 14: Evaluation of harmful gas decomposability A photocatalyst-coated body provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a base material. 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, titania aqueous dispersion as a photocatalyst, water-dispersed colloidal silica as an inorganic oxide, water-dispersed colloidal silica as an inorganic oxide having various average particle diameters shown in Table 5, water as a solvent, A surfactant was mixed at a blending ratio shown in Table 5 to obtain a photocatalyst coating solution. 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 spray-coated on the colored organic coating body heated in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, the values shown in Table 5 were obtained.

The photocatalyst-coated body having a size of 50 × 100 mm thus obtained was subjected to a gas decomposability test as follows. As a pretreatment, the photocatalyst-coated body 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. As shown in Table 5, it was found that the NOx decomposition activity can be sufficiently obtained even when the content of the photocatalyst particles in the photocatalyst layer is less than 5 parts by mass.

Examples 15 to 17: Influence of hydrolyzable silicone A photocatalyst-coated body provided with a photocatalyst layer was produced as follows. First, a colored organic coated body was prepared as a base material. 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, Table 6 shows a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, water as a solvent, a polycondensate of tetramethoxysilane as a hydrolyzable silicone, and a surfactant. To obtain a photocatalyst coating liquid. The photocatalyst coating liquid of Example 15 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 heated in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. 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 15 to 17.

The photocatalyst-coated body having a size of 50 × 100 mm thus obtained was subjected to a gas decomposability test as follows. As a pretreatment, the photocatalyst-coated body 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 obtained results were as shown in Table 6. Here, assuming that Example 15 containing no hydrolyzable silicone is 100, 50 or more represents G, and less than 50 represents NG. As shown in Table 6, 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 18 and 19: Weather resistance test (evaluation of substrate deterioration)
The photocatalyst coating body provided with the photocatalyst layer was manufactured as follows. First, a colored organic coated body was prepared as a base material. 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 surfactant are mixed at a blending ratio shown in Table 7 to obtain a photocatalyst coating liquid. It was. 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 in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. When the film thickness of the photocatalyst layer was measured by operation electron microscope observation, it was about 0.5 μm in both examples 18 and 19.

About the photocatalyst coating body of a magnitude | size of 50x100 mm obtained in this way, the weather resistance test was done as follows. The photocatalyst-coated body was put into a xenon arc type weather resistance tester (Toyo Seiki, Ci4000) combined with hydrogen peroxide spray. The intensity of the xenon lamp is 80 W / m ² (wavelength 300 to 400 nm), the concentration of hydrogen peroxide is 1%, the irradiation of the xenon lamp is 22 hours / cycle, and the spray of hydrogen peroxide is 3 minutes in the first 2 hours. Spraying-> Repeat for 2 minutes. After 200 hours, the test piece was taken out, and a cellophane tape was attached to the surface of the coating film, peeled off at once, and evaluated by the presence or absence of colored organic coating powder adhering to the adhesive surface of the tape due to coating film deterioration (choking phenomenon).

  The obtained results were as shown in Table 7. Here, G in the table indicates that almost no powder adhered to the glue surface of the tape. As shown in Table 7, it was found that a photocatalyst-coated body having a photocatalyst particle content in the photocatalyst layer of less than 5 parts by mass has sufficient weather resistance.

Examples 20 to 23: Measurement of linear transmittance A photocatalyst-coated body 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 substrate. 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 surfactant are mixed at a compounding ratio shown in Table 8 to obtain a photocatalyst coating liquid. It was. 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 above-mentioned float plate glass heated in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. When the film thickness (μm) of the photocatalyst layer was measured by operation type electron microscope observation, the values shown in Table 8 were obtained.

  With respect to the photocatalyst-coated body having a size of 50 × 100 mm thus obtained, the linear (550 nm) transmittance was measured using an ultraviolet / visible / near-infrared spectrophotometer (UV-3150, manufactured by Shimadzu Corporation) as follows. It was.

The obtained results were as shown in Table 8. Here, the evaluation criteria of the linear transmittance were as follows.
<Linear transmittance>
A: Linear (550 nm) transmittance is 95% or more B: Linear (550 nm) transmittance is 90% or more and less than 95% The photocatalyst-coated body of Table 8 showed high transparency.

<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. Details are shown in Table 9.
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.

In the following examples, the photocatalyst layer coating liquid was prepared by appropriately mixing the photocatalyst particles shown below, any inorganic oxide, and water. Details are shown in Table 10.
Photocatalyst particles / titania water dispersion (average particle size: 42 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)
Polycondensate of hydrolyzable silicone tetramethoxysilane (SiO ₂ equivalent concentration: 51 mass%. Solvent: methanol, water)
Surfactant / polyether-modified silicone surfactant

Examples 31-33: Evaluation of weather resistance (exposure outdoors)
The photocatalyst coating body provided with the intermediate | middle layer and the photocatalyst layer was manufactured as follows. First, a float plate glass was prepared as a base material. On the glass substrate heated beforehand, the intermediate | middle layer coating liquid as described in M-1 of Table 9 was spray-coated, and it dried at 120 degreeC, and obtained the intermediate | middle layer. The solid content concentration of the resin in this M-1 solution was about 20%. 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 31 to 33.

  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 surfactant are mixed at a blending ratio shown by T-1 to T-3 in Table 10. As a result, a photocatalyst 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 intermediate layer-coated body heated in advance and dried at 120 ° C. 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 31 to 33. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a photocatalyst-coated body.

  The photocatalyst-coated body having a size of 50 × 100 mm obtained in this way was exposed outdoors at an angle of 20 ° from the horizontal toward the south surface in Miyakojima using an exposure stand defined in JIS K 5600-7-6. . The appearance was visually confirmed every three months.

  The obtained results were as shown in Table 11. Here, “G” in the table shows almost no change, and “NG” shows that white bloom slightly occurs. As shown in Table 11, it was found that Miyakojima has sufficient weather resistance when the content of the photocatalyst in the photocatalyst layer is less than 5 parts by mass.

Examples 34 to 36: Evaluation of hydrophilicity by exposure to ultraviolet rays A photocatalyst-coated body provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a base material. On the glass substrate heated beforehand, the intermediate | middle layer coating liquid as described in M-1 of Table 9 was spray-coated, and it dried at 120 degreeC, and obtained the intermediate | middle layer. The solid content concentration of the resin in this M-1 solution was about 20%. 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 34 to 36.

  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 surfactant are shown in T-1, T-5 and T-6 in Table 9. The photocatalyst coating liquid was obtained by mixing at a blending ratio. 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 intermediate layer-coated body heated in advance and dried at 120 ° C. 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 34 to 36. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a photocatalyst-coated body.

The photocatalyst-coated body thus obtained was evaluated for hydrophilicity as follows. After curing the photocatalyst-coated body in a dark place for 1 day, the photocatalyst-coated surface is left for 7 days under BLB light adjusted to 1 mW / cm ^2, and the contact angle of the photocatalyst-coated surface is measured with a contact angle meter (Kyowa Interface) It was measured by Kagaku CA-X150 type). The contact angle was measured using a hydrophilic substitute.

The obtained results were as shown in Table 12. Here, the evaluation criteria for the hydrophilicity to UV exposure were as follows.
<Hydrophilicity>
A: Contact angle is less than 10 ° B: Contact angle is 10 ° or more and less than 20 ° C: Contact angle is 20 ° or more As shown in Table 12, the content of the photocatalyst particles in the photocatalyst layer is 2 parts by mass or more. It was found that high hydrophilicity was ensured.

Examples 37 and 38: Evaluation of sliding wear resistance A photocatalyst-coated body provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a base material. On the glass substrate heated beforehand, the intermediate | middle layer coating liquid as described in M-1 of Table 9 was spray-coated, and it dried at 120 degreeC, and obtained the intermediate | middle layer. The solid content concentration of the resin in this M-1 solution was about 20%. 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 37 and 38.

  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 surfactant are mixed at a mixing ratio shown in T-1 and T-7 in Table 10. As a result, a photocatalyst 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 intermediate layer-coated body heated in advance and dried at 120 ° C. 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 37 and 38. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a photocatalyst-coated body.

  The photocatalyst-coated body thus obtained was subjected to a washing resistance test as follows. The test method was performed according to JIS A6909. The photocatalyst-coated body was fixed horizontally on a test stand of a cleaning tester (No. 458 Washability Tester manufactured by Toyo Seiki Seisakusho) with the photocatalyst-coated surface facing upward. The tip of a pork brush with a dry brush weight of 450 g was immersed in a 0.5% solution of soapy water, placed on the photocatalyst coating surface, reciprocated 500 times, then removed, washed with water and dried.

The well-dried photocatalyst-coated body was irradiated with BLB light adjusted to 3 mW / cm ² for 24 hours, and then the contact angle of the photocatalyst-coated surface was measured with a contact angle meter (CA-X150 manufactured by Kyowa Interface Science). The contact angle was measured using a hydrophilic substitute.

The obtained results were as shown in Table 13. Here, the evaluation criteria of the sliding wear resistance were as follows.
<Sliding wear resistance>
A: Contact angle is less than 10 ° B: Contact angle is 10 ° or more As shown in Table 13, the photocatalyst-coated body of Example 37 was found to form a strong film against sliding.

Examples 39 and 40: Measurement of haze A photocatalyst-coated body 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 substrate. 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 surfactant are mixed at a blending ratio shown by T-1 and T-8 in Table 10. As a result, a photocatalyst 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 spin-coated on the above-mentioned substrate at 1000 rpm for 10 seconds and dried at 120 ° C. to obtain a photocatalyst layer. The haze of the photocatalyst-coated body having a size of 50 × 100 mm obtained in this manner was measured using a haze meter (haze-gard plus from Gardner).

  The obtained results were as shown in Table 14. As Table 14 shows, it turned out that the photocatalyst coating body of Example 39 can suppress a haze value to less than 1%, and can ensure transparency.

Examples 41 to 44: Evaluation of harmful gas decomposability A photocatalyst-coated body provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a base material. On the glass substrate heated beforehand, the intermediate | middle layer coating liquid as described in M-1 of Table 9 was spray-coated, and it dried at 120 degreeC, and obtained the intermediate | middle layer. The solid content concentration of the resin in this M-1 solution was about 20%. 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 44.

  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 surfactant are shown in T-1, T-2 and T-5 in Table 10. The photocatalyst coating liquid was obtained by mixing at a blending ratio. 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 intermediate layer-coated body heated in advance and dried at 120 ° C. When the film thickness of the photocatalyst layer was measured by observation with a scanning electron microscope, the values shown in Table 15 were obtained. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a photocatalyst-coated body.

The photocatalyst-coated body having a size of 50 × 100 mm thus obtained was subjected to a gas decomposability test as follows. As a pretreatment, the photocatalyst-coated body 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 NO2 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 15. As shown in Table 15, it was found that sufficient NOx decomposition activity can be obtained even when the content of the photocatalyst particles in the photocatalyst layer is less than 5 parts by mass.

Examples 45 to 47: Influence of hydrolyzable silicone A photocatalyst-coated body provided with an intermediate layer and a photocatalyst layer was produced as follows. First, a float plate glass was prepared as a base material. On the glass substrate heated beforehand, the intermediate | middle layer coating liquid as described in M-1 of Table 9 was spray-coated, and it dried at 120 degreeC, and obtained the intermediate | middle layer. The solid content concentration of the resin in this M-1 solution was about 20%. 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 45 to 47.

  On the other hand, a titania aqueous dispersion as a photocatalyst, a water-dispersed colloidal silica as an inorganic oxide, water as a solvent, a polycondensate of tetramethoxysilane as a hydrolyzable silicone, and a surfactant are listed in Table 10. The photocatalyst coating liquid was obtained by mixing at the blending ratios indicated by T-1, T-9, and T-10. In addition, the photocatalyst coating liquid of Example 45 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 intermediate layer-coated body heated in advance and dried at 120 ° C. 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 45 to 47. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a photocatalyst-coated body.

The photocatalyst-coated body having a size of 50 × 100 mm thus obtained was subjected to a gas decomposability test as follows. As a pretreatment, the photocatalyst-coated body 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 obtained results were as shown in Table 16. Here, assuming that Example 45 containing no hydrolyzable silicone is 100, 50 or more represents G, and less than 50 represents NG. As shown in Table 16, 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 48 to 51: Measurement of linear transmittance A photocatalyst-coated body 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 substrate. 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 surfactant are mixed at a mixing ratio shown in T-1 and T-5 in Table 10. As a result, a photocatalyst coating solution was obtained. 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 spray-coated on the above-mentioned float plate glass heated in advance, and dried at 120 ° C. Thus, a photocatalyst layer was formed to obtain a photocatalyst-coated body. When the film thickness (μm) of the photocatalyst layer was measured by operation-type electron microscope observation, the values shown in Table 17 were obtained.

  With respect to the photocatalyst-coated body having a size of 50 × 100 mm thus obtained, the linear (550 nm) transmittance was measured using an ultraviolet / visible / near-infrared spectrophotometer (UV-3150, manufactured by Shimadzu Corporation) as follows. It was.

The obtained results were as shown in Table 17. Here, the evaluation criteria of the linear transmittance were as follows.
<Linear transmittance>
A: Linear (550 nm) transmittance is 95% or more B: Linear (550 nm) transmittance is 90% or more and less than 95% The photocatalyst-coated body of Table 17 showed high transparency.

Examples 52 to 54: Evaluation of weather resistance of coating film-1
The photocatalyst coating body provided with the intermediate | middle layer and the photocatalyst layer was manufactured as follows. First, a float plate glass was prepared as a base material. A glass substrate heated in advance was spray-coated with a mixture of the intermediate layer coating liquid described in M-2 in Table 9 and a coloring pigment, and dried at 120 ° C. to obtain an intermediate layer. The solid content concentration of the resin in the M-2 solution was about 20%. 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 52 to 54.

  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 mixing ratio shown in T-1, T-4 and T-5 in Table 10. 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-coated body heated in advance and dried at 120 ° C. 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 52 to 54. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a photocatalyst-coated body.

  About the photocatalyst coating body of a magnitude | size of 50x100 mm obtained in this way, the weather resistance test was done as follows. The photocatalyst-coated body was put 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 18. 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 18, it was found that the photocatalyst-coated bodies of Examples 52 and 53 had sufficient weather resistance even when the photocatalyst layer was coated on an intermediate layer having a small silicon atom content.

Examples 55 and 56: Evaluation of weather resistance of coating film-2
The photocatalyst coating body provided with the intermediate | middle layer and the photocatalyst layer was manufactured as follows. First, a general-purpose epoxy resin-based primer was applied to a galvanized steel sheet as a base material and dried. The intermediate layer coating solution described in M-1 and M-3 of Table 9 was spray coated and dried at 120 ° C. to obtain an intermediate layer. The solid content concentration of the resin in the M-1 and M-2 liquids was about 20%. 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 55 using M-1 and Example 56 using M-3.

  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 surfactant are mixed at a blending ratio shown by T-1 in Table 10 to obtain a photocatalyst. A 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 intermediate layer-coated body heated in advance and dried at 120 ° C. 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 55 and 56. Thus, an intermediate layer and a photocatalyst layer were formed to obtain a photocatalyst-coated body.

About the photocatalyst coating body of a magnitude | size of 50x100 mm obtained in this way, the weather resistance test was done as follows. The photocatalyst-coated body was put into a metering weatherometer (M6T manufactured by Suga Test Instruments). The appearance of the test piece was confirmed after 150 hours.

  In Example 55 using an acrylic-modified silicone resin having a silicon atom content of 10% by mass, cracks did not occur and the weather resistance was good. On the other hand, in Example 56 using an acrylic-modified silicone resin having a silicon atom content of 16.5%, a slight occurrence of cracks was observed although it was slight.

Claims (48)

A photocatalyst-coated body comprising a substrate and a photocatalyst layer provided on the substrate,
The photocatalytic layer is
Photocatalyst particles,
Inorganic oxide particles,
The photocatalyst layer has gaps between particles in the layer. The photocatalyst layer is more than 1 part by weight and less than 5 parts by weight,
More than 85 parts by weight and less than 99 parts by weight of inorganic oxide particles;
0 parts by weight or more and less than 10 parts by weight of a hydrolyzable silicone dry product,
The total amount of the photocatalyst particles, the inorganic oxide particles, and the hydrolyzable silicone in terms of silica is 100 parts by mass,
The photocatalyst coating body of Claim 1.   The photocatalyst-coated body according to claim 1 or 2, wherein an average particle diameter of the photocatalyst particles is 10 nm or more and 100 nm or less.   The photocatalyst-coated body according to any one of claims 1 to 3, wherein the photocatalyst particles are titanium oxide particles.   The photocatalyst-coated body according to any one of claims 1 to 4, wherein the photocatalyst particles are anatase-type titanium oxide.   The photocatalyst-coated body according to any one of claims 1 to 5, wherein Cu is further present in the photocatalyst layer.   The photocatalyst-coated body according to any one of claims 1 to 6, wherein Cu is supported on the photocatalyst particles.   The photocatalyst-coated body according to any one of claims 1 to 5, wherein Cu and Ag are further present in the photocatalyst layer.   The photocatalyst-coated body according to claim 8, wherein Ag and Cu are supported on the photocatalyst particles.   The photocatalyst-coated body according to any one of claims 1 to 9, wherein the inorganic oxide particles are silica particles.   The inorganic oxide particles have a number average particle diameter of 5 nm or more and less than 40 nm, which is calculated by measuring the length of any 100 particles entering a 200,000-fold field of view with a scanning electron microscope. Item 11. The photocatalyst-coated body according to any one of items 1 to 10.   The inorganic oxide particles have a number average particle diameter of 5 nm or more and less than 20 nm, which is calculated by measuring the length of any 100 particles entering a 200,000-fold field of view with a scanning electron microscope. Item 11. The photocatalyst-coated body according to any one of items 1 to 10.   The photocatalyst-coated body according to any one of claims 1 to 12, wherein the photocatalyst layer further comprises 0 to 10 parts by mass of a surfactant.   The photocatalyst-coated body according to any one of claims 1 to 13, wherein the photocatalyst layer has a film thickness of 0.5 µm or more and 3 µm or less.   The photocatalyst layer further comprises, as an optional component, a hydrolytic polycondensation product of titanium alkoxide or a derivative of titanium alkoxide in an amount of 0 to 10 parts by mass in terms of titanium dioxide. The photocatalyst coating body of description.   The photocatalyst-coated body according to any one of claims 1 to 15, wherein the photocatalyst layer is obtained by heat drying at 200 ° C or lower.   The hydrolyzable silicone is an organosiloxane having at least one reactive group selected from the group consisting of an alkoxy group, a halogen group, and a hydrogen group. Photocatalyst painted body.   The photocatalyst-coated body according to any one of claims 1 to 16, wherein the hydrolyzable silicone is an organosiloxane having an alkoxy group.   The photocatalyst-coated body according to any one of claims 1 to 18, wherein the dried hydrolyzable silicone is a hydrolyzed polycondensate of the hydrolyzable silicone.   The photocatalyst coating body of any one of Claims 1-19 whose said base material is a base material in which the surface was formed with the organic material at least.   The photocatalyst coating body of any one of Claims 1-20 by which the said photocatalyst layer is apply | coated directly on the said base material.   The photocatalyst-coated body according to any one of claims 1 to 21, comprising an intermediate layer between the substrate and the photocatalyst layer.   The photocatalyst-coated body according to claim 22, wherein the intermediate layer comprises a silicone-modified resin.   The photocatalyst-coated body according to claim 22 or 23, wherein the intermediate layer comprises acrylic silicone.   The photocatalyst-coated body according to any one of claims 22 to 24, wherein the intermediate layer comprises an ultraviolet absorber.   The photocatalyst-coated body according to any one of claims 22 to 25, wherein the intermediate layer comprises an organic antifungal agent.   The photocatalyst-coated body according to any one of claims 1 to 26, which is used as an exterior material. It is a photocatalyst coating liquid used for manufacture of the photocatalyst coating body of any one of Claims 1-27,
A solvent,
1 to 5 parts by mass of photocatalyst particles having an average particle diameter of 10 to 100 nm,
Inorganic oxide particles exceeding 85 parts by mass and 99 parts by mass or less;
Hydrolyzable silicone of 0 parts by weight or more and less than 10 parts by weight in terms of silica;
The photocatalyst coating liquid which contains the photocatalyst particle | grains, the said inorganic oxide particle, and the total amount with the silica conversion amount of the said hydrolysable silicone being 100 mass parts.   The photocatalyst coating liquid according to claim 28, wherein an average particle diameter of the photocatalyst particles is 10 nm or more and 100 nm or less.   The photocatalyst coating liquid according to claim 29 or 30, wherein the photocatalyst particles are titanium oxide particles.   The photocatalyst coating liquid according to any one of claims 28 to 30, wherein the photocatalyst particles are anatase-type titanium oxide.   The photocatalyst coating liquid according to any one of claims 28 to 31, further comprising Cu.   The photocatalyst coating liquid according to any one of claims 28 to 31, further comprising Cu and Ag.   The photocatalyst coating liquid according to claim 32, wherein Cu is supported on the photocatalyst particles.   The photocatalyst coating liquid according to claim 33, wherein Ag and Cu are supported on the photocatalyst particles.   36. The photocatalyst coating liquid according to any one of claims 28 to 35, wherein the inorganic oxide particles are silica particles.   The inorganic oxide particles have a number average particle diameter of 5 nm or more and less than 40 nm, which is calculated by measuring the length of any 100 particles entering a 200,000-fold field of view with a scanning electron microscope. Item 37. The photocatalyst coating liquid according to any one of Items 28 to 36.   The inorganic oxide particles have a number average particle diameter of 5 nm or more and less than 20 nm, which is calculated by measuring the length of any 100 particles entering a 200,000-fold field of view with a scanning electron microscope. Item 37. The photocatalyst coating liquid according to any one of Items 28 to 36.   The photocatalyst coating liquid according to any one of claims 28 to 38, further comprising 0 part by mass or more and less than 10 parts by mass of a surfactant.   The photocatalyst according to any one of claims 28 to 39, further comprising, as an optional component, a hydrolytic condensation polymer of titanium alkoxide or a derivative of titanium alkoxide in an amount of 0 to 10 parts by mass in terms of titanium dioxide. Coating liquid.   41. The hydrolyzable silicone is an organosiloxane having at least one reactive group selected from the group consisting of an alkoxy group, a halogen group and a hydrogen group. Photocatalyst coating solution.   The photocatalyst coating liquid according to any one of claims 28 to 40, wherein the hydrolyzable silicone is an organosiloxane having an alkoxy group.   43. The photocatalyst coating liquid according to any one of claims 28 to 42, wherein the solvent is water. A coating liquid for forming the intermediate layer of the photocatalyst-coated body according to claim 22,
A solvent,
A coating liquid comprising a silicone-modified resin. A coating liquid for forming the intermediate layer of the photocatalyst-coated body according to claim 22,
A solvent,
A coating liquid comprising acrylic silicone.   The coating liquid according to claim 44 or 45, further comprising an ultraviolet absorber.   The coating liquid according to any one of claims 44 to 46, further comprising an organic antifungal agent.   The photocatalyst coating liquid according to any one of claims 44 to 47, wherein the solvent is water.