JP2005060794A - Functional aluminum building material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a functional aluminum building material which is excellent in antibacterial property, fungicidal property, antifouling performance and durability, specifically a functional aluminum building material which decomposes contamination sources such as bacteria and fungi by using ultraviolet radiation. <P>SOLUTION: The aluminum building material has a coating film containing a photocatalyst (a) and a binder component (B). Here, the photocatalyst (a) concentration in the coating film is low at the surface contacting an aluminum building material substrate but increases toward the exposed surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is a functional aluminum building material that can be easily coated, has excellent antibacterial and antifungal properties, decomposes the causative substances by the photocatalytic action and penetrates the walls and the like, and has self-cleaning properties It is related with the photocatalyst coating composition for functional aluminum building materials which can provide, and the functional aluminum building material obtained by this.

  It has been known that semiconductor fine particles having a photocatalytic action represented by titanium oxide have an antibacterial / antifungal / antifouling / deodorizing action based on the action of organic matter decomposition by the photocatalytic action. Then, using these materials, various materials that are difficult for bacteria and pupae to grow are being researched and developed. For example, Japanese Patent Application Laid-Open No. 2-6333 discloses an antibacterial powder in which an antibacterial metal such as copper or zinc is supported on the surface of titanium oxide particles, and this powder is blended with resin, rubber, glass or the like. In addition to antibacterial treatment of electrical equipment, furniture furniture, interior decoration materials, packaging materials such as food, etc. by known methods, antibacterial agents for environmental hygiene facilities and equipment Teaches that the above powder can be used. For example, in JP-A-6-65012, a titanium oxide film containing a metal such as silver, copper, zinc, or platinum is coated on a substrate made of a material such as concrete, glass, plastic, ceramics, or metal, It is disclosed that it is possible to prevent the propagation of germs and sputum on the substrate. Further, for example, in Japanese Patent Laid-Open No. 4-307066, a photocatalyst is attached to the back side of the panel, a short wavelength lamp is disposed on the back side of the panel, and the photocatalyst is activated by irradiating the photocatalyst with ultraviolet rays. A refreshing method for indoor air that attempts to deodorize a room where a panel is installed is disclosed. However, when a photocatalyst such as titanium oxide is coated on a building member made of aluminum or an aluminum alloy (hereinafter referred to as aluminum alloy), for example, a panel material, the panel surface is easily corroded (oxidized) by the strong redox action of the photocatalyst. There is. Further, there is a problem that sufficient adhesion between the aluminum alloy substrate and the photocatalyst cannot be obtained, and the coated photocatalyst film is easily peeled off. In addition, it is difficult to uniformly coat a photocatalyst on a building material having a complicated shape, and usually, when coating a photocatalyst, it is necessary to heat the substrate to a temperature exceeding 200 ° C. When the aluminum alloy is exposed to temperature, there is a problem that the strength of the aluminum alloy is significantly reduced.

  In order to solve these problems, for example, Japanese Patent Application Laid-Open No. 8-302498 discloses a semiconductor fine particle in which an anodized film is formed on the surface of a base material made of aluminum or an aluminum alloy, and further has a photocatalytic action on the anodized film. There has been proposed a building material in which a coating film containing or carrying is formed. According to the present invention, the anodic oxide film formed on the surface of the base material certainly improves the adhesion with the coating film containing or carrying the semiconductor particles having photocatalytic action formed thereon, The problem of the deterioration of the binder paint due to the photo-oxidation function of the semiconductor fine particles having the above has not been solved.

For the reasons mentioned above, it has long been self-cleaning, maintenance-free without the need for special equipment, and antibacterial / anti-bacterial films do not corrode the surface of aluminum or aluminum alloy substrates and have high adhesion. An antibacterial and anti-bacterial aluminum building material coated with a strong photocatalyst was desired.
Japanese Patent Laid-Open No. 2-6333 JP-A-6-65012 Japanese Patent Laid-Open No. 4-307066 JP-A-8-302498

  Accordingly, the object of the present invention is to solve the above-mentioned problems, maintenance-free without the need for special equipment, and the photocatalyst-containing film does not corrode the aluminum or aluminum alloy substrate surface and has high adhesion strength. The object is to provide an aluminum building material having photocatalytic activity such as antibacterial, antifungal and antifouling properties adhered in

As a result of intensive studies to solve the above problems, the present inventors have reached the present invention. That is, the present invention is as follows.
1. An aluminum building material provided with a coating containing a photocatalyst (a) and a binder component (B), wherein the concentration of the photocatalyst (a) in the coating increases from the surface in contact with the aluminum or aluminum alloy substrate toward the exposed surface. This is a functional aluminum building material.
2. An aluminum building material provided with a film containing a photocatalyst (a) and a binder component (B), wherein the concentration of the photocatalyst (a) in the film is in contact with the anodized film formed on the aluminum or aluminum alloy substrate Functional aluminum building material characterized in that it becomes higher toward the exposed surface.
3. 3. The functional aluminum building material according to claim 1, wherein the film is formed from a photocatalyst composition (C) containing a photocatalyst (a) and a binder component (B).

4). The photocatalyst (a) is a triorganosilane unit represented by the formula (1), a monooxydiorganosilane unit represented by the formula (2), a dioxyorganosilane unit represented by the formula (3), and Modified photocatalyst (A) modified with at least one modifier compound (b) selected from the group consisting of compounds having at least one structural unit selected from the group consisting of methylene fluoride (—CF ₂ —) units The functional aluminum building material according to any one of the inventions 1 to 3, wherein:
R ₃ Si- (1)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group)
_{- (R 2 SiO) - (} 2)
(In the formula, R is as defined in formula (1).)

(In the formula, R is as defined in formula (1).)
5). The functional aluminum building material according to any one of inventions 1 to 4, wherein the binder component (B) contains a phenyl group-containing silicone (BP) represented by the following formula (4).
^{_{R 1 p R 2 q X r}} SiO (4-p-q-r) / 2 (4)
(In the formula, each R ¹ represents a phenyl group, and each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or Represents a branched alkenyl group having 2 to 30 carbon atoms, each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or 1 carbon atom; Represents -20 oxime groups and halogen atoms.
And p, q, and r are 0 <p <4, 0 ≦ q <4, 0 ≦ r <4, and 0 <(p + q + r) <4, and 0.05 ≦ p / (p + q) ≦ 1 is there. )

6). The functional aluminum building material according to invention 5, wherein the phenyl group-containing silicone (BP) is a phenyl group-containing silicone (BP1) not containing an alkyl group, represented by the following formula (5).
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(In the formula, R 1 represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime group having 1 to 20 carbon atoms. And s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.

7). The functional aluminum building material according to any one of inventions 5 and 6, wherein the binder component (B) further contains an alkyl group-containing silicone (BA) represented by the following formula (6).
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. And u and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.)

8). The binder component (B) contains a phenyl group-containing silicone (BP1) not containing an alkyl group represented by formula (5) and an alkyl group-containing silicone (BA) represented by formula (6). The functional aluminum building material according to any one of inventions 1 to 4, which is characterized by the above.
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein, R ¹ represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. U and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.)

9. The alkyl group-containing silicone (BA) has a monooxydiorganosilane unit (D) represented by the formula (7) and a dioxyorganosilane unit (T) represented by the formula (8). The functional aluminum building material as described in invention 7 or 8.
— (R ² ₂ SiO) — (7)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Represents an alkenyl group.

(Wherein R ² is as defined in formula (7).)
10. The functional aluminum building material according to any one of inventions 7 to 9, which is a film having a phase separation structure for the phenyl group-containing silicone (BP) and the alkyl group-containing silicone (BA).
11. The functional aluminum building material according to invention 10, wherein the photocatalyst (a) is present in the alkyl group-containing silicone (BA) phase.
12 The functional aluminum building material according to invention 4, wherein the number average particle size of the modified photocatalyst (A) is 400 nm or less.

13. The functional aluminum building material according to invention 4, wherein the modifier compound (b) is a Si-H group-containing silicon compound (b1) represented by the formula (9).
H _x R _y SiO _{(4-xy) / 2} (9)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group, where x and y are 0 <x <4, 0 <Y <4 and (x + y) ≦ 4.)

14 The Si-H group-containing silicon compound (b1) is a mono-Si-H group-containing compound represented by the formula (10), a Si-H group-containing compound represented by the formula (11), a formula (12) The functional aluminum building material according to invention 13, which is at least one compound selected from the group consisting of H silicones represented by:

(In the formula, each R ³ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a carbon number of 5 to 20). A cycloalkyl group, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, a phenyl group, or a siloxy group represented by the formula (13).
—O— (R ⁴ ₂ SiO) _m —SiR ⁴ ₃ (13)
(In the formula, each R ⁴ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number of 1 to 1. 30 represents a fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a phenyl group, and m is an integer and 0 ≦ m ≦ 1000.)
H— (R ³ ₂ SiO) _n —SiR ³ ₂ —H (11)
(In the formula, R ³ is as defined in formula (10). N is an integer and 0 ≦ n ≦ 1000.)
(R ³ HSiO) _a (R ³ ₂ SiO) _b (R ³ ₃ SiO _1/2 ) _c (12)
(Wherein R ³ is as defined in formula (10), a is an integer of 1 or more, b is an integer of 0 or more, (a + b) ≦ 10000, and c is 0 or 2) Provided that when (a + b) is an integer of 2 or more and c = 0, the H silicone of formula (12) is a cyclic silicone, and when c = 2, the H silicone of formula (12). Is a chain silicone.)

15. The functional aluminum building material according to any one of inventions 1 and 2, wherein the binder component (B) in the coating forms a phase separation structure.
16. 3. The functional aluminum building material according to claim 1, wherein the functional aluminum building material exhibits photocatalytic activity when irradiated with light having energy higher than the band gap energy of the photocatalyst (a) contained in the coating.
17. By irradiating light with energy higher than the band gap energy of the photocatalyst (a) contained in the film, at least a part of the organic groups bonded to silicon atoms existing in the vicinity of the photocatalyst (a) particles are hydroxyl groups and The functional aluminum building material according to any one of Inventions 4, 5, 7, and 8, wherein the functional aluminum building material is substituted with a siloxane bond.
18. A photocatalyst composition (C) comprising a photocatalyst (a) and a binder component (B), wherein the photocatalyst coating composition for functional aluminum building materials is characterized in that the film according to any one of the inventions 1 and 2 is formed. .

  The present invention can exhibit excellent antibacterial, antifungal and antifouling properties over a long period of time without deteriorating the aluminum building material base material itself due to light in the living environment, and requires a complicated process. Therefore, it is possible to provide a functional aluminum building material that is easy to manufacture.

Hereinafter, the present invention will be described in detail.
The functional aluminum building material of the present invention is an aluminum building material provided with a film containing a photocatalyst (a) and a binder component (B), wherein the concentration of the photocatalyst (a) in the film is in contact with the base material of the aluminum building material. It is characterized by becoming higher toward the exposed surface.
At this time, with respect to the photocatalyst content (concentration) of 100 in the entire film, the effect of improving the photocatalytic ability and the hydrophilization ability is expressed that the relative concentration in the vicinity of the surface side in contact with the exposed surface is antifouling It is preferable because the antibacterial and antifungal effects are increased. The relative concentration in the vicinity of the surface side is more preferably 150 or more, and further preferably 200 or more. Moreover, it is preferable at the point of the interface deterioration prevention effect that the relative density | concentration of the surface vicinity which contacts an aluminum building material base material is 50 or less. The relative concentration in the vicinity of the surface in contact with the aluminum building material substrate is more preferably 10 or less, and even more preferably 0.
In addition, the concentration of the photocatalyst (a) in the film according to the present invention may gradually increase from the surface in contact with the aluminum building material substrate toward the other exposed surface, or simply on the surface in contact with the aluminum building material substrate. The photocatalyst concentration may be low, the photocatalyst concentration on the other exposed surface may be high, and the change therebetween may be discontinuous.

In the present invention, the photocatalyst (a) refers to a substance that undergoes an oxidation or reduction reaction upon irradiation with light. That is, when light (excitation light) with an energy larger than the energy gap between the conduction band and the valence band (ie, short wavelength) is irradiated, excitation of electrons in the valence band (photoexcitation) occurs. It is a substance that can generate conduction electrons and holes. At this time, various chemical reactions are performed using the reducing power of electrons generated in the conduction band and / or the oxidizing power of holes generated in the valence band. be able to. For example,
Examples thereof include oxidative decomposition reactions of various organic substances. Therefore, if this photocatalyst is immobilized on the surface of the aluminum building material, various organic substances (contaminants) adhering to the aluminum building material can be oxidatively decomposed using light energy, and the surface of the aluminum building material can be made hydrophilic. It becomes possible to keep in sex.

In the present invention, the photocatalytic activity means that an oxidation or reduction reaction is caused by light irradiation. It is possible to determine whether or not the surface is photocatalytically active by measuring the decomposability of the organic material such as a dye during light irradiation on the surface of the material. The surface having photocatalytic activity has excellent decomposition activity of contaminating organic substances such as bacteria and fungi, and exhibits antifouling properties, antibacterial properties and fungicidal properties.
In the present invention, examples of the photocatalyst (a) useful for making the surface of the aluminum building material photocatalytically active include TiO ₂ , ZnO, SrTiO ₃ , CdS, GaP, InP, GaAs, BaTiO ₃ , BaTiO ₄ , and BaTi. ₄ O ₉ , K ₂ NbO ₃ , Nb ₂ O ₅ , Fe ₂ O ₃ , Ta ₂ O ₅ , K ₃ Ta ₃ Si ₂ O ₃ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , BiVO ₄ , NiO, Cu ₂ O, SiC, MoS ₂ , InPb, RuO ₂ , CeO ₂ , Ta ₃ N _{5 and the} like, and further a layered oxide having at least one element selected from Ti, Nb, Ta, V (for example, JP JP 62-74452 A, JP 2-172535 A, JP 7-24329 A, JP 8-89799 A, JP 8-898 A. No. 0, JP-A-8-89804, JP-A-8-198061, JP-A-9-248465, JP-A-10-99694, JP-A-10-244165, etc.) it can.

Among these photocatalysts (a), TiO ₂ (titanium oxide) is preferable because it is harmless and has excellent chemical stability. As titanium oxide, any of anatase, rutile, and brookite can be used.
When a visible light responsive photocatalyst capable of expressing photocatalytic activity and / or hydrophilicity by irradiation with visible light (for example, a wavelength of about 400 to 800 nm) is selected as the photocatalyst (a) used in the present invention, The functional aluminum building material of the invention is preferable because it can exhibit antifouling performance, an organic matter decomposing action, etc. even in a place where ultraviolet rays such as indoors are not sufficiently irradiated.

Any visible light responsive photocatalyst can be used as long as it exhibits photocatalytic activity and / or hydrophilicity with visible light. For example, TaON, LaTiO ₂ N, CaNbO ₂ N, LaTaON ₂ , and CaTaO ₂ N can be used. Oxynitride compounds such as JP-A-2002-66333, oxysulfide compounds such as Sm ₂ Ti ₂ S ₂ O ₇ (see JP-A-2002-233770, for example), and nitriding such as Ta ₃ N ₅ Compounds, oxides containing metal ions in the d10 electronic state such as CaIn ₂ O ₄ , SrIn ₂ O ₄ , ZnGa ₂ O ₄ , and Na ₂ Sb ₂ O ₆ (see, for example, JP 2002-59008 A), ammonia and urea In the presence of nitrogen-containing compounds such as titanium oxide precursors (titanium oxysulfate, titanium chloride, alkoxytita Etc.) or nitrogen-doped titanium oxide obtained by firing high surface titanium oxide (for example, JP 2002-29750 A, JP 2002-87818 A, JP 2002-154823 A, JP 2001-207082 A). See), sulfur-doped titanium oxide obtained by firing titanium oxide precursors (titanium oxysulfate, titanium chloride, alkoxytitanium, etc.) in the presence of sulfur compounds such as thiourea, hydrogen plasma treatment or under vacuum Or oxygen-deficient titanium oxide obtained by heat treatment (for example, see JP-A-2001-98219), and further, photocatalyst particles are treated with a halogenated platinum compound (for example, JP-A-2002-239353). And treatment with tungsten alkoxide (see JP 2001-286755 A). The surface-treated photocatalyst obtained by this can be mentioned suitably.

Among the visible light responsive photocatalysts, oxynitride compounds and oxysulfide compounds have a large photocatalytic activity by visible light, and can be used particularly preferably.
Furthermore, the above-mentioned photocatalyst (a) is preferably added or fixed with a metal such as Pt, Rh, Ru, Nb, Cu, Sn, Ni, Fe and / or an oxide thereof, or coated with porous calcium phosphate or the like. Or a photocatalyst (see, for example, JP-A-10-244166).
The crystal particle size (primary particle size) of the photocatalyst (a) is preferably 1 to 400 nm, and more preferably a photocatalyst of 1 to 50 nm is suitably selected.

As the form of the photocatalyst (a) of the present invention, any of powder, dispersion, and sol can be used.
In the present invention, the modification of the photocatalyst (a) means that at least one modifier compound (b) described later is immobilized on the surface of the photocatalyst (a) particles. The immobilization of the above modifier compound on the surface of the photocatalyst particles is considered to be due to van der Waals force (physical adsorption), Coulomb force, or chemical bonding. In particular, modification using a chemical bond is preferable because the interaction between the modifier compound and the photocatalyst is strong, and the modifier compound is firmly immobilized on the surface of the photocatalyst particles.
By using the photocatalyst (a) of the present invention as the modified photocatalyst (A), when the film containing the photocatalyst (a) is formed on the aluminum building material base material of the present invention, the photocatalyst (a) in the film Since the formation of a structure in which the concentration of the coating increases from the surface in contact with the aluminum building material base to the other exposed surface of the coating is facilitated particularly when combined with the binder component (B) described later, it is very preferable. .

  In the present invention, the properties of the photocatalyst (a) used for modification are important factors for the dispersion stability of the modified photocatalyst (A), film-forming properties, and expression of various functions. That is, as the photocatalyst (a) used for the modification of the present invention, the number average dispersed particle size of a mixture of primary particles and secondary particles (which may be either primary particles or secondary particles) is 400 nm or less. These photocatalysts are preferable because the surface characteristics of the modified photocatalyst can be effectively utilized. In particular, when a photocatalyst having a number average dispersed particle size of 100 nm or less is used, the film of the present invention formed from a photocatalyst composition (C) containing a modified photocatalyst (A) to be produced and a binder component (B) described later is modified. This is very preferable because the photocatalyst (A) can be efficiently present on the surface (exposed surface) of the coating. More preferably, the photocatalyst (a) having a thickness of 80 nm or less and 3 nm or more, more preferably 50 nm or less and 3 nm or more is suitably selected.

  As these photocatalysts (a), it is preferable to use a photocatalyst sol instead of a photocatalyst powder for the following reasons. In general, powders composed of fine particles form secondary particles in which single crystal particles (primary particles) are strongly agglomerated, so there are many surface properties that are wasted, but it is very difficult to disperse to primary particles. It is. On the other hand, in the case of a photocatalyst sol, the photocatalyst particles do not dissolve but exist in a form close to primary particles, so that the surface characteristics can be used effectively. It can be preferably used because it effectively exhibits various functions. Here, the photocatalyst sol used in the present invention means that the photocatalyst particles are preferably 0.01 to 70% by mass, more preferably 0.1 to 50% by mass in water and / or an organic solvent, and primary particles and / or secondary particles. Dispersed as secondary particles.

  Here, examples of the organic solvent used in the photocatalyst sol include alcohols such as ethylene glycol, butyl cellosolve, n-propanol, isopropanol, n-butanol, ethanol and methanol, and aromatic hydrocarbons such as toluene and xylene. , Aliphatic hydrocarbons such as hexane, cyclohexane and heptane, esters such as ethyl acetate and n-butyl acetate, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethers such as tetrahydrofuran and dioxane, dimethylacetamide, dimethyl Examples include amides such as formamide, halogen compounds such as chloroform, methylene chloride, and carbon tetrachloride, dimethyl sulfoxide, nitrobenzene, and a mixture of two or more of these.

  Taking a titanium oxide sol as an example of the photocatalyst sol, for example, a titanium oxide hydrosol in which water is substantially used as a dispersion medium and titanium oxide particles are peptized therein can be exemplified. (Here, substantially using water as a dispersion medium means that water is contained in the dispersion medium in an amount of about 80% by mass or more.) Adjustment of such a sol is known and can be easily produced ( For example, see JP-A-63-17221, JP-A-7-819, JP-A-9-165218, JP-A-11-43327, etc.). For example, metatitanic acid produced by heating and hydrolyzing an aqueous solution of titanium sulfate or titanium tetrachloride is neutralized with aqueous ammonia, and the precipitated hydrous titanium oxide is filtered, washed, and dehydrated to obtain aggregates of titanium oxide particles. It is done. Titanium oxide hydrosol can be obtained by peptizing the agglomerates under the action of nitric acid, hydrochloric acid, ammonia or the like and performing hydrothermal treatment. In addition, as titanium oxide hydrosol, titanium oxide particles are peptized under the action of acid or alkali, or dispersion stabilizer such as sodium polyacrylate is used as required without using acid or alkali. Sols that are used and dispersed in water under strong shear forces can also be used. Further, anatase-type titanium oxide sols having excellent dispersion stability even in an aqueous solution having a pH near neutral and whose particle surface is modified with a peroxo group can be easily obtained by, for example, the method proposed in JP-A-10-67516. Can be obtained.

The titanium oxide hydrosol described above is commercially available as a titania sol. (For example, “STS-02” manufactured by Ishihara Sangyo Co., Ltd., “TO-240” manufactured by Tanaka Transcript Co., Ltd., etc.)
The titanium oxide in the titanium oxide hydrosol is preferably 50% by mass or less, more preferably 30% by mass or less. More preferably, it is 30 mass% or less and 0.1 mass% or more.
Such hydrosols have a relatively low viscosity (20 ° C.). In the present invention, the viscosity of the hydrosol is preferably in the range of about 0.05 mPa · s to 2000 mPa · s. More preferably, it is 0.5 mPa * s-1000 mPa * s, More preferably, it is 1 mPa * s-500 mPa * s.

Further, for example, a cerium oxide sol (for example, see JP-A-8-59235) or a layered oxide sol having at least one element selected from the group consisting of Ti, Nb, Ta, and V (for example, No. 25123, JP-A-9-67124, JP-A-9-227122, JP-A-9-227123, JP-A-10-259023, etc.), etc. It is known as well as titanium oxide sol.
Furthermore, a visible light responsive photocatalyst sol that can be suitably used in the present invention is also commercially available. (For example, “NTB-200” manufactured by Showa Denko KK, “TSS” manufactured by Sumitomo Chemical Co., Ltd., etc.)

  In addition, a photocatalyst organosol in which an organic solvent is substantially used as a dispersion medium and in which photocatalyst particles are dispersed is a compound having a phase transfer activity such as polyethylene glycol (for example, different first phase and second phase). A third phase is formed at the interface with the phase, the first phase, the second phase, the third phase are mutually dissolved and / or solubilized compounds) and diluted with an organic solvent (for example, JP-A-10-167727), a method for preparing a sol by dispersing and transferring it in an organic solvent insoluble in water with an anionic surfactant such as sodium dodecylbenzenesulfonate (for example, JP-A-58-29863). Gazette) and alcohols having a boiling point higher than that of water such as butyl cellosolve are added to the photocatalyst hydrosol, and then the water can be obtained by (reduced pressure) distillation or the like.In addition, a titanium oxide organosol in which an organic solvent is substantially used as a dispersion medium and titanium oxide particles are dispersed therein is commercially available (for example, “TKS-251” manufactured by Teika Co., Ltd.). Here, substantially using an organic solvent as a dispersion medium means that the organic solvent is contained in the dispersion medium in an amount of about 50% by mass or more.

In the present invention, at least one modifier compound (b) used to obtain the modified photocatalyst (A) is a triorganosilane unit represented by the formula (1), a monooxy represented by the formula (2). From the group consisting of compounds having at least one structural unit selected from the group consisting of diorganosilane units, dioxyorganosilane units represented by formula (3), and methylene fluoride (—CF ₂ —) units. To be elected.
R ₃ Si- (1)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group)
_{- (R 2 SiO) - (} 2)
(In the formula, R is as defined in formula (1).)

(In the formula, R is as defined in formula (1).)
In the modified photocatalyst (A) in which the surface of the photocatalyst particle is modified with the modifier compound (b) having the structural unit described above, the surface energy of the particle surface is very small.
In the present invention, the modification treatment of the photocatalyst (a) with the modifier compound (b) is carried out in the presence or absence of water and / or an organic solvent in the same manner as the above-described photocatalyst (a). b) is preferably mixed at a mass ratio (a) / (b) = 1/99 to 99.9 / 0.1, more preferably (a) / (b) = 10/90 to 99/1. Preferably, it can be obtained by heating at 0 to 200 ° C., more preferably at 10 to 80 ° C., or by changing the solvent composition of the mixture by (reduced pressure) distillation or the like.

  Here, when performing the above modification treatment, examples of organic solvents that can be used include aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as hexane, cyclohexane, and heptane, ethyl acetate, and n-butyl acetate. Esters, alcohols such as ethylene glycol, butyl cellosolve, isopropanol, n-butanol, ethanol and methanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethers such as tetrahydrofuran and dioxane, amides such as dimethylacetamide and dimethylformamide , Halogen compounds such as chloroform, methylene chloride, carbon tetrachloride, dimethyl sulfoxide, nitrobenzene, and a mixture of two or more thereof.

Examples of the modifier compound (b) used to obtain the modified photocatalyst (A) of the present invention include Si-H groups, hydrolyzable silyl groups (alkoxysilyl groups, hydroxysilyl groups, halogenated silyl groups, Acetoxysilyl group, aminoxysilyl group, etc.), epoxy compounds, acetoacetyl groups, thiol groups, acid anhydride groups and other photocatalyst particles (a) reactive with silicon compounds, fluoroalkyl compounds, fluoroolefin polymers, etc. Can be mentioned.
Other examples of the modifier compound (b) include interaction with photocatalyst particles (a) such as polyoxyalkylene group, sulfonic acid group, and carboxyl group by van der Waals force, Coulomb force, and the like. Examples thereof include a silicon compound having a structure, a fluoroalkyl compound, and a fluoroolefin polymer.

In the present invention, when the Si-H group-containing silicon compound (b1) represented by the composition formula (9) is used as the modifier compound (b), the surface of the photocatalyst particles can be modified very efficiently. preferable.
H _x R _y SiO _{(4-xy) / 2} (9)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group, where x and y are 0 <x <4, 0 <Y <4 and (x + y) ≦ 4.)

In the present invention, the modification of the photocatalyst (a) with the Si—H group-containing silicon compound (b1) represented by the above composition formula (9) is carried out in the presence or absence of water and / or an organic solvent. The mass ratio (a) / (b1) = 1/99 to 99.9 / 0.1, more preferably (a) / (b1), between (a) and the Si—H group-containing silicon compound (b1). = 10/90 to 99/1, preferably by mixing at 0 to 200 ° C. By this modification operation, hydrogen gas is generated from the mixed solution, and when the photocatalyst sol is used as the photocatalyst (a), an increase in the average dispersed particle diameter is observed. For example, when titanium oxide is used as the photocatalyst (a), a decrease in Ti—OH groups is observed as a decrease in absorption at 3630 to 3640 cm ^{−1 in} the IR spectrum by the above modification.

From these, when the Si-H group-containing silicon compound (b1) represented by the above formula (9) is selected as the modifier compound (b), the modified photocatalyst (A1) of the present invention is Si-H. This is very preferable because it is not a simple mixture of the group-containing silicon compound (b1) and the photocatalyst (a) but can be expected to cause some kind of interaction between the two due to a chemical reaction. In fact, the modified photocatalyst (A) thus obtained is very excellent in dispersion stability, chemical stability, durability and the like in an organic solvent.
In the present invention, the modification of the photocatalyst (a) with the Si—H group-containing silicon compound (b1) represented by the above formula (9) is preferably performed using a dehydrogenative condensation catalyst for Si—H groups. It can also be carried out at 150 ° C.

In this case, the dehydrogenation condensation catalyst may be fixed to the photocatalyst (a) in advance by a method such as a photoreduction method and may be modified with the Si-H group-containing silicon compound (b1), or the presence of the dehydrogenation condensation catalyst. Under the above, the photocatalyst (a) may be modified with the Si—H group-containing compound silicon (b1).
Here, the dehydrogenative condensation catalyst for the Si-H group is an active hydrogen group such as a Si-H group and a hydroxyl group (Ti-OH group in the case of titanium oxide) existing on the photocatalyst surface, a thiol group, an amino group, or a carboxyl group. Furthermore, it means a substance that accelerates the dehydrogenation condensation reaction with water or the like, and the use of the dehydrogenation condensation catalyst makes it possible to modify the surface of the photocatalyst under mild conditions.
Examples of the dehydrogenative condensation catalyst include platinum group catalysts, that is, ruthenium, rhodium, palladium, osmium, iridium, platinum simple substance and compounds thereof, and simple substances such as silver, iron, copper, cobalt, nickel, tin and compounds thereof. Can be mentioned. Of these, platinum group catalysts are preferred, and platinum alone and its compounds are particularly preferred.

Here, as the platinum compound, for example, platinum chloride (II), tetrachloroplatinic acid (II), platinum chloride (IV), hexachloroplatinic acid (IV), hexachloroplatinum (IV) ammonium, hexachloroplatinum (IV) Potassium, platinum hydroxide (II), platinum dioxide (IV), dichloro-dicyclopentadienyl-platinum (II), platinum-vinylsiloxane complex, platinum-phosphine complex, platinum-olefin complex, etc. can be used. .
In the Si—H group-containing silicon compound represented by the above formula (9) of the present invention, the Si—H group is a preferred functional group for modifying the photocatalyst with good selectivity under mild conditions. On the other hand, the hydrolyzable group can also be used for the modification of the photocatalyst, but in order to suppress side reactions and improve the stability of the resulting modified photocatalyst, the content thereof should be smaller. preferable.

  Examples of the Si-H group-containing silicon compound (b1) represented by the above formula (9) that can be suitably used in the present invention include a mono-Si-H group-containing compound represented by the formula (10), a formula (11) Si-H group-containing compound having no hydrolyzable silyl group, at least one selected from the group consisting of Si-H group-containing compound represented by formula (12) and H silicone represented by formula (12) Can be mentioned.

(In the formula, each R ³ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a carbon number of 5 to 20). A cycloalkyl group, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, a phenyl group, or a siloxy group represented by the formula (13).
—O— (R ⁴ ₂ SiO) _m —SiR ⁴ ₃ (13)
(In the formula, each R ⁴ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number of 1 to 1. 30 represents a fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a phenyl group, and m is an integer and 0 ≦ m ≦ 1000.)
H— (R ³ ₂ SiO) _n —SiR ³ ₂ —H (11)
(In the formula, R ³ is as defined in formula (10). N is an integer and 0 ≦ n ≦ 1000.)
(R ³ HSiO) _a (R ³ ₂ SiO) _b (R ³ ₃ SiO _1/2 ) _c (12)
(Wherein R ³ is as defined in formula (10), a is an integer of 1 or more, b is an integer of 0 or more, (a + b) ≦ 10000, and c is 0 or 2) Provided that when (a + b) is an integer of 2 or more and c = 0, the H silicone of formula (12) is a cyclic silicone, and when c = 2, the H silicone of formula (12). Is a chain silicone.)

  In the present invention, specific examples of the mono-Si—H group-containing compound represented by the formula (10) include, for example, bis (trimethylsiloxy) methylsilane, bis (trimethylsiloxy) ethylsilane, bis (trimethylsiloxy) n-propylsilane. Bis (trimethylsiloxy) i-propylsilane, bis (trimethylsiloxy) n-butylsilane, bis (trimethylsiloxy) n-hexylsilane, bis (trimethylsiloxy) cyclohexylsilane, bis (trimethylsiloxy) phenylsilane, bis (triethylsiloxy) ) Methylsilane, bis (triethylsiloxy) ethylsilane, tris (trimethylsiloxy) silane, tris (triethylsiloxy) silane, pentamethyldisiloxane, 1,1,1,3,3,5,5-heptamethyltrisilo Sun, 1,1,1,3,3,5,5,6,6-nonamethyltetrasiloxane, trimethylsilane, ethyldimethylsilane, methyldiethylsilane, triethylsilane, phenyldimethylsilane, diphenylmethylsilane, cyclohexyldimethylsilane , T-butyldimethylsilane, di-t-butylmethylsilane, n-octadecyldimethylsilane, tri-n-propylsilane, tri-i-propylsilane, tri-i-butylsilane, tri-n-hexylsilane, triphenyl Examples thereof include silane, allyldimethylsilane, 1-allyl-1,1,3,3-tetramethyldisiloxane, chloromethyldimethylsilane, and 7-octenyldimethylsilane.

  Among these mono-Si-H group-containing compounds, bis (trimethylsiloxy) methylsilane and tris are preferred because of the good reactivity (dehydrogenation condensation reaction) and low surface energy of Si-H groups during photocatalytic modification treatment. Those represented by the following formula (14) having a siloxy group in the molecule, such as (trimethylsiloxy) silane, pentamethyldisiloxane and the like and having no phenyl group are preferable.

(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 1 to 30 carbon atoms, or a carbon number of 5 to 20). A cycloalkyl group, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, or a group consisting of one or more selected from a siloxy group represented by formula (13b), and R ^At least one of ⁵ is a siloxy group represented by the formula (13b).
—O— (R ^{4 ′} ₂ SiO) _m —SiR ^{4 ′} ₃ (13b)
(Wherein R ^{4 ′} each independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number. Represents 1 to 30 fluoroalkyl groups, m is an integer, and 0 ≦ m ≦ 1000.))

  In the present invention, specific examples of the both-terminal Si—H group-containing compound represented by the above formula (11) include 1,1,3,3-tetramethyldisiloxane, 1,1,3,3,5, and the like. , 5-hexamethyltrisiloxane, 1,1,3,3,5,5,7,7-octamethyltetrasiloxane and the like H-terminal polydimethylsiloxanes having a number average molecular weight of 50000 or less, Number average molecular weight of 50,000 or less such as 3-tetraethyldisiloxane, 1,1,3,3,5,5-hexaethyltrisiloxane, 1,1,3,3,5,5,7,7-octaethyltetrasiloxane H-terminal polydiethylsiloxanes, 1,1,3,3-tetraphenyldisiloxane, 1,1,3,3,5,5-hexaphenyltrisiloxane, 1,1,3,3,5,5 , 7,7-octa H-terminal polydiphenylsiloxanes having a number average molecular weight of 50,000 or less, 1,3-diphenyl-1,3-dimethyl-disiloxane, 1,3,5-trimethyl-1,3,5-triphenyl -H-terminal polyphenylmethylsiloxanes having a number average molecular weight of 50000 or less, such as trisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenyl-tetrasiloxane, dimethylsilane, ethylmethyl Examples thereof include silane, diethylsilane, phenylmethylsilane, diphenylsilane, cyclohexylmethylsilane, t-butylmethylsilane, di-t-butylsilane, n-octadecylmethylsilane, and allylmethylsilane.

Among these, the number average molecular weight is preferably 10000 or less, more preferably 2000 or less, more preferably due to the good reactivity of the Si—H group (dehydrogenation condensation reaction) and the low surface energy during the modification of the photocatalyst. Preferably 1000 or less H-terminated polydialkylsiloxanes (formula (15)) can be suitably used as the Si-H group-containing compound at both ends.
H— (R ⁶ ₂ SiO) _d —SiR ⁶ ₂ —H (15)
(In the formula, each R ⁶ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, or a linear or branched fluoroalkyl group having 1 to 30 carbon atoms. D Is an integer and 0 ≦ d ≦ 1000.)

The H silicone represented by the above formula (12) used in the present invention has a number average molecular weight of preferably 5,000 or less, more preferably from the viewpoint of dispersion stability (preventing aggregation of photocatalyst particles) during photocatalytic modification treatment. H silicone of 2000 or less, more preferably 1000 or less can be suitably used.
Moreover, when the fluororesin (b2) having the structure represented by the general formula (20) is used as the modifier compound (b) used in the present invention, a modified photocatalyst (A) modified with the fluororesin (A) ) Is preferable because it is excellent in both decomposability of harmful substances and organic base material protection.

(Wherein A ^{1 to} A ⁵ may be the same or different and are each selected from a fluorine atom, a hydrogen atom, a chlorine atom, an alkyl group having 1 to 6 carbon atoms, and a halo-substituted alkyl group having 1 to 6 carbon atoms) Y represents a w-valent organic group having a molecular weight of 14 to 50000 (a group having a w-value other than the bond to the main chain of the organic group Y, preferably a group having a methylene fluoride unit, more preferably V represents an epoxy group, a hydroxyl group, an acetoacetyl group, a thiol group, a cyclic acid anhydride group, a carboxyl group, a sulfonic acid group, a polyoxyalkylene group, or a hydrolyzable silyl group. Represents at least one functional group selected from the group consisting of: k is an integer of 0 or more and 1000000 or less, and l is an integer of 1 or more and 100000 or less, provided that k = 0 is preferable. The at least one fluorine atom in ^A 3 to A ^5, more preferably an integer of .w 1 to 20 representing the ^A 3, ^{A 4} are both fluorine atoms.)

In the present invention, the modification of the photocatalyst (a) with the fluorine-based resin (b2) represented by the formula (20) is performed in the presence or absence of water and / or an organic solvent. The resin (b2) is preferably a mass ratio (a) / (b2) = 1/99 to 99.9 / 0.1, more preferably a ratio of (a) / (b2) = 10/90 to 99/1 It is preferably obtained by mixing at 0 to 200 ° C. and preferably by changing the solvent composition of the mixture by distillation under reduced pressure.
Preferable examples of the fluororesin (b2) include a perfluorocarbon sulfonic acid polymer fluororesin (b2 ′) having a structure represented by the formula (21), for example.

(In the formula, x is an integer of 1 to 1000000, y represents an integer of 1 to 100000, m represents an integer of 0 to 20, and n represents an integer of 0 to 20).
In the modified photocatalyst (A) of the present invention, the preferred form is that the number average dispersed particle diameter of the mixture of primary particles and secondary particles of the modified photocatalyst (which may be either primary particles or secondary particles) is 400 nm. Hereinafter, it is more preferably 1 nm to 100 nm, particularly preferably 5 nm to 80 nm. A sol state is preferable.

In particular, when a modified photocatalyst sol having a number average dispersed particle size of 100 nm or less is used in the photocatalyst composition (C) of the present invention, the concentration of the modified photocatalyst particles is small in the vicinity of the interface in contact with the aluminum building material substrate, and in the vicinity of the surface of the film. In this case, it is advantageous for forming a film having an anisotropic distribution in the surface direction, which is largely distributed, and it is very preferable because a film having a large photocatalytic activity is formed without interfacial deterioration with the aluminum building material base due to photocatalytic action. Such a modified photocatalyst sol can be obtained by using the above-mentioned photocatalyst sol as a photocatalyst to be modified with the above modifier compound (b).

Conventionally, a numerical value simply displayed as a particle diameter in titanium dioxide or the like is a primary particle diameter (crystallite diameter) in many cases, and is not a numerical value considering a secondary particle diameter due to aggregation.
The photocatalyst composition (C) for forming a film of the present invention comprises a photocatalyst (a) (preferably a modified photocatalyst (A)) and a binder component (B), and its mass ratio (a) / (B ) Is preferably 0.1 / 99.9 to 90/10, and more preferably (a) / (B) is included at 1/99 to 50/50.
The modified photocatalyst (A) of the present invention is modified with a modifier compound (b) having a structure having a very small surface energy {formula (1) to (3), at least one selected from methylene fluoride units}. Therefore, when forming a film, it has the property of easily moving to the surface of the film in contact with air.

Here, as the binder component (B) of the present invention, by using a photocatalyst (a), in particular, a binder component having a surface energy higher than that of the modified photocatalyst (A), the above properties of the modified photocatalyst (A) are promoted. The photocatalyst composition (C) of the present invention can have a large self-gradient with respect to the distribution of the photocatalyst (a), particularly the modified photocatalyst (A). Here, the self-gradient property means that when a film is formed from the photocatalyst composition (C), the photocatalyst (a), particularly the modified photocatalyst (A), in the formation process, the properties of the film or the interface with which it contacts (particularly hydrophilic / hydrophobic) ) Means to autonomously form a structure having a concentration gradient of the photocatalyst (a), particularly the modified photocatalyst (A).
As the binder component (B) of the present invention, when a resin having a surface energy of 2 mN / m or more, preferably 5 mN / m or more larger than that of the photocatalyst (a) (preferably the modified photocatalyst (A)) is selected, the self-gradient Is very preferable.

Here, the surface energy and the relative difference between the surface energies can be determined by referring to, for example, Polymer Handbook (published by A Wiley-interscience publication in the United States) or by the following method.
That is, the base material which each has those films | membranes from the photocatalyst (a) which comprises the said photocatalyst composition (C), especially modified photocatalyst (A), and a binder component (B) is adjusted, deionized water is dripped and 20 The contact angle (θ) at ° C. is measured, and the surface energy of each can be obtained by the following empirical formulas for Sell and Neumann.

[Wherein γs represents the surface energy (mN / m) of the film obtained by measuring the contact angle of deionized water, and γl represents the surface energy of water {72.8 mN / m (20 ° C.)}.
In the photocatalyst composition (C) of the present invention, the compound that can be used for the binder component (B) is not particularly limited as long as it has a surface energy that satisfies the above conditions. Various monomers, synthetic resins, natural resins, and the like In addition, after the formation of a film or a molded body, those that are cured by drying, heating, moisture absorption, light irradiation, or the like can also be mentioned. Further, the form thereof may be in a solvent-free state (pellet, powder, liquid, etc.) or may be dissolved or dispersed in a solvent, and is not particularly limited.

As the synthetic resin, a thermoplastic resin and a curable resin (thermosetting resin, photocurable resin, moisture curable resin, etc.) can be used. For example, silicone resin, acrylic resin, methacrylic resin, fluororesin, Alkyd resin, amino alkyd resin, vinyl resin, polyester resin, styrene-butadiene resin, polyolefin resin, polystyrene resin, polyketone resin, polyamide resin, polycarbonate resin, polyacetal resin, polyether ether ketone resin, polyphenylene oxide resin, polysulfone resin, Polyphenylene sulfone resin, polyether resin, polyvinyl chloride resin, polyvinylidene chloride resin, urea resin, phenol resin, melamine resin, epoxy resin, urethane resin, silicone-acrylic resin, water glass and zirco Um compounds, and inorganic compounds such as titanium peroxide.
Examples of the natural polymer include cellulose resins such as nitrocellulose, isoprene resins such as natural rubber, protein resins such as casein, and starch.

In the present invention, as the binder component (B) used in the photocatalyst composition (C), the phenyl group-containing silicone (BP) represented by the following formula (4) is more surface energy than the modified photocatalyst (A) of the present invention. Since the siloxane bond (—O—Si—) constituting the skeleton does not undergo oxidative decomposition due to photocatalysis, it can be most preferably used.
^{_{R 1 p R 2 q X r}} SiO (4-p-q-r) / 2 (4)
(In the formula, each R ¹ represents a phenyl group, and each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or Represents a branched alkenyl group having 2 to 30 carbon atoms, each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or 1 carbon atom; Represents an oxime group of ˜20, a halogen atom, and p, q and r are 0 <p <4, 0 ≦ q <4, 0 ≦ r <4, and 0 <(p + q + r) <4, and 0 .05 ≦ p / (p + q) ≦ 1.)
Examples of the phenyl group-containing silicone (BP) represented by the above formula (4) include at least one structure of a siloxane bond represented by the general formulas (16), (17), (18), and (19). Mention may be made of silicone.

— (R ⁷ ₂ SiO) — (17)

(In the formula, each R ⁷ independently represents a phenyl group, a linear or branched alkyl group having 1 to 30 carbon atoms, or a cycloalkyl group having 5 to 20 carbon atoms.)

The silicone containing the above-described structure is, for example, a general formula RSiX ₃ (wherein R represents a phenyl group, a linear or branched alkyl group having 1 to 30 carbon atoms, or a cycloalkyl group having 5 to 20 carbon atoms). Each X is independently selected from the group consisting of a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, and a halogen atom. 4) represented by a trifunctional silane derivative and / or a bifunctional silane derivative represented by the general formula R ₂ SiX ₂ and / or ₄ represented by the general formula SiX 4. It can be prepared by partially hydrolyzing / condensing a functional silane derivative and, if necessary, terminating with a monofunctional silane derivative represented by the general formula R ₃ SiX and / or an alcohol. The polystyrene-converted weight average molecular weight of the partial condensate of the silane derivative monomer thus obtained is preferably 100 to 100,000, more preferably 400 to 50,000.

Among these, when a phenyl group-containing silicone represented by the above formula (4) is selected to contain a ladder structure represented by the above formula (16) of 10 mol% or more, preferably 40 mol% or more, the present invention The photocatalyst-containing film formed from the photocatalyst composition (C) is extremely excellent in terms of hardness, heat resistance, weather resistance, antibacterial properties, mold resistance, stain resistance, chemical resistance, etc. preferable. In particular, those having a phenyl ladder structure as the ladder structure [wherein all R ⁷ in the formula (16) are phenyl groups] are preferable because the physical properties of the above-described photocatalyst-containing film are greatly improved. Such ladder structure, for example can be identified by the presence of absorption derived from two siloxane bonds near 1040 cm ^-1 and 1160 cm ^-1 in the infrared absorption spectrum.
(See JFBrown. Jr., etal .: J. Am. Chem. Soc., 82, 6194 (1960).)
The phenyl group-containing silicone (BP) represented by the above formula (4) used in the present invention preferably has a Ph—Si bond (Ph: phenyl group).

That is, in the photocatalyst composition (C) of the present invention, the modifier compound (b) having a structure having a very small surface energy {formula (1) to (3), at least one selected from methylene fluoride units}. By using the binder component (B) containing a phenyl group-containing silicone (BP) having a surface energy higher than that of the modified photocatalyst (A) as the binder of the modified photocatalyst (A) that has been modified, the photocatalyst composition of the present invention (C) is preferable because it can have a very high self-gradient with respect to the distribution of the modified photocatalyst (A).
Such a self-gradient effect by the phenyl group-containing silicone (BP) having a high surface energy is obtained by converting the phenyl group (R ¹ ) into the phenyl group (R ¹ ) and R ² (R ² is linear or branched). Represents an alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, and an alkenyl group having 2 to 20 carbon atoms) (hereinafter referred to as (R ¹ + R ² )). }, A phenyl group-containing silicone (BP) represented by the above formula (4) having 5 mol% or more of Is preferred.

In addition, the self-tilting effect described above increases as the ratio of the phenyl group (R ¹ ) to (R ¹ + R ² ) increases. Therefore, the more preferable phenyl group-containing silicone of the binder component (B) used in the photocatalyst composition of the present invention is more preferably a ratio of phenyl group (R ¹ ) to (R ¹ + R ² ) of 10 mol% or more. Is 20 mol% or more, more preferably 50 mol% or more.

In the photocatalyst composition (C) of the present invention, the phenyl group-containing silicone (BP) used in the binder component (B) is more preferably an alkyl group represented by the following formula (5), which exhibits the above-described effects. It is a phenyl group-containing silicone (BP1) that does not contain.
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein, R ¹ represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, and s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.)

Further, when the binder component (B) further contains an alkyl group-containing silicone (BA) represented by the following formula (6), the film formed from the photocatalyst composition of the present invention has a film formability, hardness, and heat resistance. It is preferable because it is excellent in terms of properties, antibacterial properties, antifungal properties, stain resistance, chemical resistance, and the like.
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. U and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.)

Further, as the alkyl group-containing silicone (BA) to be mixed with the phenyl group-containing silicone (BP1), the monooxydiorganosilane unit (D) represented by the formula (7) and the diester represented by the formula (8) are used. When a oxyorganosilane unit (T) having a structure having a molar ratio of preferably (D) / (T) = 100/0 to 5/95, more preferably 90/10 to 10/90 is used. As a result, the stress relaxation action of the alkyl group-containing silicone (BA) is increased, and the crack resistance of the photocatalyst-containing film produced from the photocatalyst composition (C) of the present invention is improved, resulting in extremely excellent weather resistance. .
— (R ² ₂ SiO) — (7)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Represents an alkenyl group of

(Wherein R ² is as defined in formula (7).)
In the present invention, in order to improve long-term weather resistance, the binder component (B) preferably forms a phase separation structure, and particularly preferably forms a microphase separation structure.
For example, as the binder component (B), the above-mentioned photocatalyst (a), particularly the binder resin (B ′) having a higher surface energy than the modified photocatalyst (A) and the alkyl group-containing silicone (BA) represented by the above formula (6) ), Preferably in a mass ratio (B ′) / (BA) = 5/95 to 95/5, more preferably (B ′) / (BA) = 30/70 to 90/10 The photocatalyst-containing film formed from the photocatalyst composition (C) of the present invention has a photocatalyst (a) in a binder in which a binder resin (B ′) and an alkyl group-containing silicone (BA) having a high surface energy are phase-separated. This is preferable because it has a dispersed structure and excellent long-term weather resistance.

Here, the phase separation between the binder component (B ′) having a high surface energy and the alkyl group-containing silicone (BA) is preferably a phase that is not a continuous layer, preferably 1 nm ³ to 1 μm ³ , more preferably 10 nm ^{3 to} 0.1 μm ³ , More preferably, a more effective effect can be obtained when a domain having a size of 10 nm ^{3 to} 0.001 μm ³ is formed and microphase separation is performed.
In addition, the state in which the photocatalyst (a) is present in the alkyl group-containing silicone (BA) phase in a phase-separated state with the binder resin (B ′) having a high surface energy is more on the surface of the photocatalyst-containing film. Is preferred because it can be present.
As the binder resin (B ′) having a high surface energy that is phase-separated from the alkyl group-containing silicone (BA) in the present invention, the above-mentioned phenyl group-containing silicone (BP) is a siloxane bond (—O—Si—) constituting the skeleton. ) Is preferable because it does not undergo oxidative degradation due to photocatalysis, and phenyl group-containing silicone (BP1) not containing an alkyl group is particularly preferable.

At this time, each of the phenyl group-containing silicone (BP1) and the alkyl group-containing silicone (BA) has a polystyrene-reduced weight average molecular weight measured by GPC, preferably 100 to 10,000, more preferably 500 to 6, 000, more preferably 700 to 4,000, is preferable because the above-described binder component (B) easily forms a microphase separation structure.
The binder component (B) used in the photocatalyst composition (C) of the present invention is any of a type dissolved in a solvent, a type dispersed in a solvent, and a type not mixed with a solvent (liquid or solid). Also good.

In the photocatalyst composition (C) of the present invention, the phenyl group-containing silicone (BP) represented by the above formula (4) does not have a reactive group (X in the formula (4)). A photocatalyst-containing film obtained from the photocatalyst composition (C) of the present invention having a reactive group (X in formula (4) (that is, 0 <r in formula (4)). Is preferable because it is excellent in hardness, heat resistance, antibacterial property, antifungal property, chemical resistance, durability and the like. For the same reason, 0 <t in formula (5) and 0 <v in formula (6) are preferable.
In the photocatalyst composition (C) of the present invention, the phenyl group-containing silicone (BP) represented by the above formula (4) has a reactive group (X in the formula (4)) as a hydroxyl group and / or a hydrolyzable group. In the case where it has, a conventionally known hydrolysis catalyst or curing catalyst is preferably added in an amount of 0.01 to 20% by mass, more preferably 0.1 to 5% by mass with respect to the phenyl group-containing silicone (BP). be able to.

The hydrolysis catalyst is preferably an acidic hydrogen halide, a carboxylic acid, a sulfonic acid, an acidic or weakly acidic inorganic salt, or a solid acid such as an ion exchange resin.
The amount of the hydrolysis catalyst is preferably in the range of 0.001 to 5 mol with respect to 1 mol of the hydrolyzable group on the silicon atom.
Examples of the curing catalyst include basic compounds such as sodium hydroxide, potassium hydroxide, sodium methylate, sodium acetate, tetramethylammonium chloride, tetramethylammonium hydroxide; tributylamine, diazabicycloundecene, ethylenediamine. Amine compounds such as diethylenetriamine, ethanolamines, γ-aminopropyltrimethoxysilane, γ- (2-aminoethyl) -aminopropyltrimethoxysilane; titanium compounds such as tetraisopropyl titanate, tetrabutyl titanate; Aluminum compounds such as propoxide, aluminum acetylacetonate, aluminum perchlorate, aluminum chloride; tin acetylacetonate, dibutyltin octoate Tin compounds such as tyrates and dibutyltin dilaurate; metal-containing compounds such as cobalt octylate, cobalt acetylacetonate and iron acetylacetonate; acidic such as phosphoric acid, nitric acid, phthalic acid, p-toluenesulfonic acid and trichloroacetic acid Examples thereof include compounds.

  In the photocatalyst composition (C) of the present invention, when the phenyl group-containing silicone (BP) represented by the above formula (4) has a Si—H group, a crosslinking agent such as a polyfunctional alkenyl compound is used for the Si—H group. The alkenyl group is preferably added so that the amount is preferably 0.01 to 2 equivalents, more preferably 0.1 to 1 equivalents. The polyfunctional alkenyl compound may be anything as long as it has an alkenyl group and reacts with the Si—H group to accelerate curing, but has 2 to 30 carbon atoms such as a vinyl group, an allyl group, or a hexenyl group. Alkenyl group-containing silicones having monounsaturated hydrocarbon groups are generally used.

  Further, for the purpose of promoting the reaction between the Si—H group and the polyfunctional alkenyl compound, the catalyst is preferably 1 to 10000 ppm, more preferably 1 to 10000 based on the total amount of the phenyl group-containing silicone (BP) and the polyfunctional alkenyl compound. You may add in the ratio of 1000 ppm. As the catalyst, a platinum group catalyst, that is, a ruthenium, rhodium, palladium, osmium, iridium, or platinum compound is suitable, and a platinum compound and a palladium compound are particularly suitable. Examples of platinum compounds include platinum chloride (II), tetrachloroplatinic acid (II), platinum chloride (IV), hexachloroplatinic acid (IV), hexachloroplatinum (IV) ammonium, hexachloroplatinum (IV) potassium, hydroxide Platinum (II), platinum dioxide (IV), dichloro-dicyclopentadienyl-platinum (II), platinum-vinylsiloxane complex, platinum-phosphine complex, platinum-olefin complex, platinum simple substance, alumina, silica and activated carbon The thing which carry | supported solid platinum is mentioned. Examples of the palladium compound include palladium (II) chloride, ammonium tetraamminepalladium (II) chloride, palladium (II) oxide and the like. The platinum group catalyst is preferably used in an amount of 5 to 1000 ppm in terms of platinum group metal based on the total amount of Si-H group-containing silicone and polyfunctional alkenyl compound. It can be increased / decreased according to the curing rate and the like. Moreover, you may add activity inhibitors, such as various organic nitrogen compounds, an organic phosphorus compound, and an acetylene type compound, for the purpose of suppressing the activity of a platinum group catalyst and extending pot life if desired.

  Further, the photocatalyst composition (C) of the present invention includes silica, alumina, zirconium oxide, antimony oxide, rare earth oxide and the like for the purpose of improving the hardness, scratch resistance and hydrophilicity of the photocatalyst-containing film formed therefrom. Metal oxide fine particles may be added in the form of powder or sol. However, these metal oxide fine particles do not have the ability as a binder like the binder component (B) in the present invention, and reduce the flexibility (flexibility and impact resistance) of the film as with the photocatalyst. Therefore, the addition amount of the metal oxide is preferably such that the total weight of the photocatalyst (A) and the metal oxide is 50% by mass or less in the photocatalyst-containing film formed from the photocatalyst composition (C).

  The photocatalyst composition (C) of the present invention may be in a solvent-free state (liquid, solid) or dissolved or dispersed in a solvent, and is not particularly limited, but when used as a coating agent, A dissolved or dispersed state in a solvent is preferred. At this time, the total amount of the modified photocatalyst (A1) and the binder component (B) in the photocatalyst composition (C) is preferably 0.01 to 95% by mass, more preferably 0.1 to 70% by mass.

  Examples of the solvent used in the photocatalyst composition (C) of the present invention include water, alcohols such as ethylene glycol, butyl cellosolve, isopropanol, n-butanol, ethanol and methanol, aromatic hydrocarbons such as toluene and xylene, hexane, Aliphatic hydrocarbons such as cyclohexane and heptane, esters such as ethyl acetate and n-butyl acetate, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethers such as tetrahydrofuran and dioxane, dimethylacetamide, dimethylformamide and the like Amides, halogen compounds such as chloroform, methylene chloride, carbon tetrachloride, dimethyl sulfoxide, nitrobenzene and the like can be mentioned. These solvents are used alone or in combination.

In addition, the photocatalyst composition (C) of the present invention usually contains components that are usually added to the paint as necessary, for example, pigments, fillers, dispersants, light stabilizers, wetting agents, thickeners, rheology control agents, An antifoaming agent, a plasticizer, a film forming aid, a rust preventive agent, a dye, a preservative, and the like can be selected, combined and blended depending on the purpose.
In the photocatalyst composition (C) of the present invention, when the self-gradient property is very high (that is, the exposed surface that is not the aluminum building material substrate with respect to the modified photocatalyst (A) content (concentration) of 100 in the film). When the relative concentration in the vicinity of the surface in contact with is preferably 150 or more, more preferably 200 or more), the mass ratio of the modified photocatalyst (A) to the binder component (B) is preferably (A ) / (B) = 0.1 / 99.9 to 40/60, more preferably (A) / (B) = 0.1 / 99.9 to 30/70 content of the modified photocatalyst (A) Even in a very small range, the film formed has excellent photocatalytic activity by light irradiation. In addition, such a film having a low photocatalyst content exhibits the original physical properties of the binder component (B), and thus has excellent strength and flexibility (flexibility, impact resistance) and the like.

The functional aluminum building material in the present invention is preferably heat-treated at 20 ° C. to 500 ° C., more preferably 30 ° C. to 200 ° C., if desired, after applying the photocatalyst composition (C) to an aluminum building material substrate and drying, for example. Or by irradiating with ultraviolet rays or the like to form a film. Examples of the coating method include spraying, flow coating, roll coating, brush coating, casting, sponge coating, knife coating, gravure coating, screen coating, engraving roll, and the like. -Known methods such as a lacquer method, a flexo coat method, a dipping method, and electrodeposition coating or electrostatic coating.
Under the present circumstances, the film thickness of the film | membrane formed from the photocatalyst composition (C) of this invention becomes like this. Preferably it is 0.1-200 micrometers, More preferably, it is 0.2-20 micrometers, More preferably, it is 0.5-10 micrometers.
At this time, the state of the film may be a continuous film, a discontinuous film, an island-shaped dispersion film, or the like.

Metals such as Ag, Cu, and Zn can be added to the surface layer of the functional aluminum building material of the present invention. The surface layer to which the metal is added can kill bacteria and sputum attached to the surface even in the dark.
The functional aluminum building material of the present invention is preferably such that an anodized film is formed on the surface of a base material made of aluminum or an aluminum alloy, and further a photocatalyst-containing film is formed on the anodized film. The anodized film is an insulating film, and has a microporous structure with irregularities with numerous pores having a diameter of about 5 nm to 200 nm opened on the surface. Therefore, the oxidation / reduction action of the photocatalyst on the aluminum alloy metal is barriered to some extent by the insulating effect, and the adhesion of the photocatalyst-containing film of the present invention can be improved by the anchor effect by the microporous structure.
The aluminum building material base material that can be used to obtain the functional aluminum building material of the present invention is subjected to surface treatment in advance for the purpose of adjusting the foundation, improving adhesion, sealing the porous base material, smoothing, and patterning. You can also Examples of the surface treatment include polishing, degreasing, plating treatment, chromate treatment, flame treatment, and coupling treatment.

  The functional aluminum building material of the present invention exhibits photocatalytic activity when irradiated with light (excitation light) having an energy higher than the band gap energy of the photocatalyst (a) contained in the photocatalyst-containing coating, and exhibits excellent antifouling and antibacterial properties. , Expresses fungicidal properties. At this time, the photocatalyst (a) is a triorganosilane unit represented by the above formula (1), a monooxydiorganosilane unit represented by the formula (2), or a dioxyorgano represented by the formula (3). In the case of the modified photocatalyst (A) modified with at least one modifier compound (b) selected from the group consisting of compounds having at least one structural unit selected from the group consisting of silane units, excitation light At least a part of the organic group (R) bonded to the silicon atom of the modifier compound (b) present in the vicinity of the photocatalyst (a) particles by irradiation is substituted with a hydroxyl group by the decomposition action of the photocatalyst. As a result, the hydrophilicity of the surface of the film of the present invention is increased, and when the generated hydroxyl groups are subjected to a dehydration condensation reaction to form a siloxane bond, the hardness of the film becomes very high. Such a state is preferable in the aspect of the present invention.

Similarly, when the above-described silicone is used as the binder component (B), at least a part of the organic group bonded to the silicon atom of the silicone present in the vicinity of the photocatalyst (a) particles by excitation light irradiation is the photocatalyst. When the hydroxyl group is substituted by the decomposition action to increase the hydrophilicity of the surface of the film of the present invention, and when a dehydration condensation reaction between the generated hydroxyl groups proceeds to form a siloxane bond, the hardness of the film becomes very high. Such a state is preferable in the aspect of the present invention.
In the present invention, as a light source having a higher energy than the band gap energy of the photocatalyst (a), in addition to light obtained in a general residential environment such as sunlight and indoor lighting, black light, xenon lamp, mercury lamp, Light such as LED can be used.

The present invention will be specifically described by the following examples, reference examples and comparative examples, but these do not limit the scope of the present invention.
In Examples, Reference Examples and Comparative Examples, various physical properties were measured by the following methods.
1. Particle size distribution and number average particle size The sample was diluted with an appropriate solvent so that the photocatalyst content in the sample was 1 to 20% by mass, and measured using a wet particle size analyzer (Nikkiso Microtrac UPA-9230).
2. Weight average molecular weight It calculated | required by the gel permeation chromatography (GPC) using the analytical curve created using the polystyrene sample.
The conditions for GPC are as follows.
Apparatus: Tosoh HLC-8020 LC-3A type chromatograph column: TSKgel G1000H _XL , TSKgel G2000H _XL, and TSKgel G4000H _XL (all manufactured by Tosoh) were used in series.
-Data processing device: CR-4A type data processing device manufactured by Shimadzu Corporation-Mobile phase:
Tetrahydrofuran (used for analysis of phenyl group-containing silicone)
Toluene (used to analyze silicones that do not contain phenyl groups)
-Flow rate: 1.0 ml / min.
-Sample preparation method It diluted with the solvent used for a mobile phase (concentration was adjusted suitably in the range of 0.5-2 weight%), and used for the analysis.

3. Infrared absorption spectrum The infrared absorption spectrum was measured using a FT / IR-5300 type infrared spectrometer manufactured by JASCO Corporation.
4). Measurement of ²⁹ Si nuclear magnetic resonance Measurement was performed using JNM-LA400 manufactured by JEOL.
5). Film hardness It calculated | required as pencil hardness (scratch of a coating film) according to JIS-K5400.
6). Film hardness after ultraviolet irradiation The surface of the film was irradiated with light of FL20S BLB type black light manufactured by Toshiba Lighting & Technology for 7 days, and then measured by the above method (5).
At this time, the UV intensity measured using a Topcon UVR-2 type UV intensity meter {using a TOPCON UD-36 type light receiving part (corresponding to light with a wavelength of 310 to 400 nm) as the light receiving part} is 1 mW / cm. ^It was adjusted to be ² .

7). Contact angle of water with respect to sample surface A drop of deionized water was placed on the surface of the sample and left at 20 ° C. for 1 minute, and then measured using a CA-X150 contact angle meter manufactured by Kyowa Interface Science.
The smaller the water contact angle, the more hydrophilic the sample surface.
8). Change in hydrophilicity (hydrophobicity) of the sample surface before and after ultraviolet irradiation After the sample surface was irradiated with ultraviolet rays for 7 days by the method 6 above, the contact angle of water was measured by the method 7 above.
9. Weather resistance (gloss retention)
An exposure test (irradiation: 60 ° C. for 4 hours, dark / wet: 40 ° C. for 4 hours) was performed using a DPWL-5R type dew panel light control weather meter manufactured by Suga Test Instruments. The 60 ° -60 ° specular reflectance after 1000 hours of exposure was measured as the final gloss value, divided by the initial gloss value, and this value was calculated as the gloss retention.

10. Evaluation of inclined structure of photocatalyst After embedding the sample in an epoxy resin (Quetol 812), an ultrathin section having a thickness of 50 to 60 nm was prepared with a ULTRACUT-N type microtome manufactured by Reichert, Germany, and applied to a mesh with a supporting film. Loaded. Subsequently, RuO ₄ vapor dyeing was performed for about 5 minutes, and then carbon deposition was performed to prepare a microscopic sample, and a coating cross section was observed by TEM.
The conditions for TEM observation are as follows.
・ Device: Hitachi HF2000 type ・ Acceleration voltage: 125kV
The location of photocatalytic titanium oxide was analyzed by EDX analysis of Ti element.
In addition, observation of the film formed on the aluminum plate having the acrylic urethane base coat layer was performed by roughly cutting the sample with a DAD321 type dicing saw manufactured by DISCO Engineering Service, performing FIB (Focused Ion Beam) processing, and using TEM Observation of the cross section of the film was performed.
The FIB processing conditions are as follows.
Equipment used: Hitachi FB2000 machining conditions: Acceleration voltage (30 kV)
Ion source: Ga
The conditions for TEM observation are as follows.
・ Device: Hitachi HF2000 ・ Acceleration voltage: 200kV

11. Impact resistance In accordance with JIS-K5400, the DuPont type (500 g x 50 cm) was evaluated.
12 Adhesion test piece is subjected to a scotch tape test (film adhesion test using cellophane adhesive tape described in 5.8 of JIS H 8602), and a scratch test is performed according to the method specified in JIS H 8504. Each was tested for film adhesion.

13. Antifungal test A potato dextrose agar medium sterilized in advance was placed in a petri dish and solidified. A test piece (5 cm × 1 cm) was placed on the agar medium. Subsequently, 5 platinum Aspergillus niger (IFO 4414) separately cultured in 10 ml of a 0.005% by mass dioctyl sodium sulfosuccinate aqueous solution was collected, and spores were separated by centrifugation. After spraying the spore in 10 ml of GPLP medium onto a petri dish test piece and irradiating it with a fluorescent lamp (100 W) at room temperature for 14 days, it is resistant to mold based on the appearance of the sample (visually evaluated). Evaluation was made in the following two stages.
○: No growth of hyphae ×: Mycelia cover 50-100% of the surface

14 Placed in a sample a plastic petri dish which has been sterilized antimicrobial test 5 cm × 1 cm by ultraviolet irradiation, the bacterial solution prepared as the number of bacteria E. coli is about 10 ⁵ / ml, the sample in each dish 0 Each 5 ml was dropped, and the petri dish was covered with a polyethylene film to block it from the outside air, thereby preventing the bacterial solution on the specimen sample from drying and the entry of bacteria from the outside. Subsequently, after irradiating the light of FL20SBLB type black light manufactured by Toshiba Lighting & Technology from outside the petri dish for 4 hours, the bacterial solution was washed out from the petri dish, transferred to the medium, and the number of viable bacteria was measured. Based on the death rate, antibacterial properties were evaluated in the following three stages.
Death rate = {(initial viable cell count−viable cell count after test) / initial viable cell count} × 100
○: Death rate 80% or more △: Death rate 20% or more and less than 80% ×: Death rate 20% or less UV intensity is a UVR-2 type UV intensity meter manufactured by Topcon {as a light receiving unit, a UD-36 type light receiving unit manufactured by Topcon (Corresponding to light having a wavelength of 310 to 400 nm)} was adjusted so that the ultraviolet intensity measured using 2} was ² mW / cm ² .

15. Antifouling performance A sample cut into 5 cm x 1 cm is placed in a 120 ml glass bottle, filled with 5 cigarettes of smoke, and a cigarette spear is attached to the sample. The sample was irradiated with light for 4 hours, and the antifouling performance was evaluated in the following three stages based on the appearance (visually evaluated) of the sample.
At this time, the UV intensity measured using a Topcon UVR-2 type UV intensity meter {using a TOPCON UD-36 type light receiving part (corresponding to light with a wavelength of 310 to 400 nm) as the light receiving part} is ² mW / cm ^2. It adjusted so that it might become.
○: Coloring due to cigarette dust completely disappeared △: Coloring due to cigarette dust becomes light ×: No change in coloring due to cigarette dust

16. Weather resistance (appearance)
An exposure test (irradiation: 60 ° C. for 4 hours, dark / wet: 40 ° C. for 4 hours) was performed using a DPWL-5R type dew panel light control weather meter manufactured by Suga Test Instruments. Based on the appearance (visual evaluation) of the sample after 1000 hours of exposure, the weather resistance was evaluated in the following three stages.
○: No change in appearance △: Whitening occurs
X: Peeling of the photocatalyst-containing film occurs

[Reference Example 1]
Synthesis of phenyl group-containing silicone (BP1-1).
After 26.0 g of phenyltrichlorosilane was added to 78 g of dioxane in a reactor having a reflux condenser, a thermometer, and a stirring device, the mixture was stirred at room temperature for about 10 minutes. A mixture of 3.2 g of water and 12.9 g of dioxane was added dropwise thereto over about 30 minutes while maintaining the reaction solution at 10 to 15 ° C., followed by further stirring at 10 to 15 ° C. for about 30 minutes, The reaction solution was heated to 60 ° C. and stirred for 3 hours. The resulting reaction solution was cooled to 25-30 ° C., 392 g of toluene was added dropwise over about 30 minutes, and then the reaction solution was again heated to 60 ° C. and stirred for 2 hours.

The resulting reaction solution was cooled to 10 to 15 ° C., and 19.2 g of methanol was added over about 30 minutes. Thereafter, stirring was further continued at 25 to 30 ° C. for about 2 hours, and then the reaction solution was heated to 60 ° C. and stirred for 2 hours. The solvent was distilled off from the resulting reaction solution at 60 ° C. under reduced pressure to obtain a phenyl group-containing silicone (BP1-1) having a ladder skeleton having a weight average molecular weight of 3600. (In the obtained phenyl group-containing silicone (BP1-1), absorptions (1130 cm ⁻¹ and 1037 cm ⁻¹ ) derived from the stretching vibration of the ladder skeleton in the IR spectrum were observed.)
^Further, 29 wherein the Si-nuclear magnetic resonance measurement results from the phenyl group-containing silicone obtained (BP1-1) _{was (Ph) 1 (OCH 3)} 0.58 SiO 1.21. (Here, Ph represents a phenyl group.)

[Reference Example 2]
Synthesis of alkyl group-containing silicone (BA-1).
After adding 136 g (1 mol) of methyltrimethoxysilane and 120 g (1 mol) of dimethyldimethoxysilane to 300 g of methanol in a reactor having a reflux condenser, a thermometer and a stirring device, the mixture was stirred at room temperature for about 10 minutes. did. Under ice cooling, a mixture of 12.6 g (0.7 mol) of 0.05N aqueous hydrochloric acid and 63 g of methanol was added dropwise over about 40 minutes for hydrolysis. After completion of the dropwise addition, the mixture was further stirred at 10 ° C. or lower for about 20 minutes and at room temperature for 6 hours.
Then, the alkyl group containing silicone (BA-1) of the weight average molecular weight 3600 was obtained by distilling a solvent off from the obtained reaction liquid under reduced pressure at 60 degreeC. When the structure of the obtained alkyl group-containing silicone (BA-1) was measured by ²⁹ Si nuclear magnetic resonance, signals indicating T structure and D structure were confirmed, and the ratio was T structure: D structure = 1: 1. there were.
^The average composition formula of the above alkyl group-containing silicone obtained from the measurement results of 29 Si nuclear magnetic resonance (BA-1) _{was (CH 3) 1.5 (OCH 3} ) 0.27 SiO 1.12 .

[Reference Example 3]
Adjustment of silicone composition (B-1).
To a mixture of 6 g of the phenyl group-containing silicone (BP1-1) synthesized in Reference Example 1 and 3 g of the alkyl group-containing silicone (BA-1) synthesized in Reference Example 2, 14.7 g of toluene, 29.8 g of isopropanol, and butyl cellosolve 15.1g was added and the solution of the binder component (B-1) was obtained by stirring at room temperature.
From the average composition formula of each composition, the average composition formula of the binder component (B-1) is (Ph) _0.67 (CH ₃ ) _0.5 (OCH ₃ ) _0.47 SiO _1.18. Can be calculated. (Here, Ph represents a phenyl group.)

[Reference Example 4]
TKS-251 {trade name of titanium oxide organosol (manufactured by TEIKA), dispersion medium: mixed solvent of toluene and isopropanol, TiO ₂ concentration 20% by weight, average By adding 40 g of a 20 wt% toluene solution of bis (trimethylsiloxy) methylsilane to 40 g of crystallite diameter 6 nm (catalog value) at 50 ° C. over about 5 minutes, and continuing stirring at 50 ° C. for 12 hours, A modified photocatalyst organosol (A-1) having good dispersibility was obtained. At this time, the amount of hydrogen gas produced by the reaction of bis (trimethylsiloxy) methylsilane was 718 ml at 23 ° C. Moreover, when the obtained modified titanium oxide organosol was coated on a KBr plate and IR spectrum was measured, disappearance of absorption of Ti—OH group (3630 to 3640 cm ⁻¹ ) was observed.

1 and 2 show the particle size distributions of TKS-251 before the modification treatment and the obtained modified photocatalyst organosol (A-1), respectively. The resulting modified photocatalyst organosol (A-1) has a single particle size distribution (number average particle size is 25 nm), and further a single dispersion of TKS-251 before the modification treatment (number average particle size is 12 nm). As can be seen from FIG.
Subsequently, 20 g of the modified photocatalyst organosol (A-1) was added to 68 g of the solution of the silicone component (B-1) prepared in Reference Example 3 at room temperature with stirring, and a curing catalyst (dibutyltin dilaurate) 0 .5 g was added with stirring to obtain a photocatalyst composition (C-1).

Spray a 1mm thick aluminum plate (JIS, H, 4000 (A1050P)) cut to 50mm x 60mm with Mighty Rack White {trade name of acrylic urethane resin paint (two-component mixed type)} (manufactured by Nippon Paint)} And dried at room temperature for 3 days. After spray-applying the photocatalyst composition (C-1) to the obtained aluminum plate coated with acrylic urethane so as to have a film thickness of 2 μm, it is dried at room temperature for 1 hour and heated at 150 ° C. for 30 minutes. Thus, a test plate (D-1) having a photocatalytic coating film was obtained.
The test plate (D-1) having the obtained photocatalyst coating film was subjected to FIB processing, and the result of observation of the coating film cross section by TEM is shown in the photograph of FIG. Moreover, the illustration of the photograph of Fig.3 (a) is FIG.3 (b). A photocatalyst coating film (indicated by reference numeral 2 in FIG. 3B) containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 3B), and pigment titanium oxide (FIG. 3 (in FIG. 3B). The modified photocatalyst particles are not present at the interface with the acrylic urethane film (indicated by reference numeral 3 in FIG. 3B) including the reference numeral 4 in b), and the entire surface of the photocatalyst coating film is the modified photocatalyst. It was observed that it was covered with particles.

The test plate (D-1) having the photocatalyst coating film obtained had a pencil hardness of H and a contact angle with water of 105 °. Moreover, the impact resistance test passed.
Moreover, the pencil hardness after the ultraviolet-ray (black light) irradiation of the test board (D-1) which has the obtained photocatalyst coating film was 5H or more, and the contact angle of water was 0 degree.
Furthermore, the gloss retention by an exposure test (after 1000 hours) using a dew panel light control weather meter was 98%, indicating very good weather resistance.
Subsequently, the photocatalyst composition (C-1) is spray-coated on an epoxy resin (Quetol 812), dried at room temperature for 2 days, and then heated at 50 ° C. for 3 days to have a smooth photocatalyst coating film. An epoxy resin (D-2) was obtained.

After embedding the obtained epoxy resin having a photocatalyst coating film (D-2) to epoxy resin (Quetol812), to create the ultra-thin sections of a thickness of 50~60nm by microtome, a phenyl group-containing silicone with RuO ₄ ( The result of observing the cross section of the coating film by TEM after dyeing BP1-1) is shown in the photograph of FIG. Moreover, the illustration of the photograph of Fig.4 (a) is FIG.4 (b).
A photocatalyst coating film (indicated by reference numeral 2 in FIG. 4 (b)) containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 4 (b)) and an epoxy resin (in FIG. 4 (b)). It was observed that almost no modified photocatalyst particles were present at the interface with the photocatalyst coating film, and the entire surface of the photocatalyst coating film was covered with the modified photocatalyst particles.

4B is a boundary portion between the modified photocatalyst particle phase 1 and the binder phase 7 not containing the modified photocatalyst particles, and an enlarged photograph of the portion is shown in FIG. (A). Moreover, the illustration of the photograph of Fig.5 (a) is FIG.5 (b).
FIG. 5A shows a binder phase containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 5B) and a binder phase not containing modified photocatalyst particles (reference numeral 7 in FIG. 5B). Can be observed. In the binder phase not containing the modified photocatalyst particles (indicated by reference numeral 7 in FIG. 5B), the phenyl group-containing silicone dyed with RuO ₄ and the undyed alkyl group-containing silicone are composed of a microphase-separated structure. It can be observed that it exists.

[Reference Example 5]
A photocatalyst composition (C-2) was obtained in the same manner as in Reference Example 4 except that 10 g of unmodified TKS-251 was used instead of 20 g of the modified photocatalyst organosol (A-1).
Using the obtained photocatalyst composition (C-2), the same operation as in Reference Example 4 was performed to obtain a test plate (D-3) having a photocatalyst coating film (titanium oxide content is the same as in Reference Example 4). It was.
The test plate (D-3) having a photocatalyst coating film obtained had a pencil hardness of H and a contact angle with water of 97 °.
The test plate (D-3) having the photocatalytic coating film obtained had a pencil hardness of 3H after irradiation with ultraviolet light (black light) and a water contact angle of 94 °.

Further, in a 200-hour exposure test using a dew panel light control weather meter, the gloss retention was 10% or less, and a choking phenomenon was observed.
Subsequently, the photocatalyst composition (C-2) was spray-coated on an epoxy resin (Quetol 812), dried at room temperature for 2 days, and then heated at 50 ° C. for 3 days to form a smooth photocatalyst coating film. The obtained epoxy resin (D-4) was obtained.
After embedding the obtained epoxy resin having a photocatalyst coating film (D-4) to the epoxy resin (Quetol812), to create the ultra-thin sections of a thickness of 50~60nm by microtome, a phenyl group-containing silicone with RuO ₄ ( The result of having observed the cross section of the coating film by TEM after dyeing | staining BP1-1) is shown to the photograph of Fig.6 (a). FIG. 6B is an illustration of the photograph of FIG.

  A photocatalyst coating film (indicated by reference numeral 2 in FIG. 6B) containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 6B), and an epoxy resin (FIG. 6B) as a base material There are many modified photocatalyst particles at the interface with the reference number 5 in the figure, and the exposed surface of the photocatalyst coating film is all alkyl group-containing silicone without the modified photocatalyst particles (reference number 8 in FIG. 6B). It was observed that the photocatalytic activity could not be expected.

[Example 1]
The photocatalyst composition (C-1) prepared in Reference Example 4 was applied on an aluminum plate on which an anodized film having a film thickness of 10 μm was formed in a sulfuric acid electrolytic bath so that the dry film thickness was about 3 μm, and 30 minutes at 130 ° C. calcined, manufactured by Toshiba Lighting & Technology Corporation FL20SBLB type black light light [manufactured by Topcon UVR-2 type ultraviolet intensity meter (light receiving unit: Topcon UD-36 type light receiving portion) so that the measured ultraviolet intensity becomes 2 mW / cm ² using a Adjustment] A functional aluminum building material sample (E-1) was prepared by irradiation for 5 days.
As a result of measuring the adhesion of this sample (E-1), both the Scotch tape test and the scratch test were good, and there was no peeling. The antibacterial and antifungal properties were both very good (◯). Furthermore, when the antifouling performance was evaluated, a very good result (◯) was obtained.
Moreover, the external appearance change in the weather resistance test of this sample (E-1) was very favorable ((circle)).

[Comparative Example 1]
A functional aluminum building material sample was prepared in the same manner as in Example 1 except that the photocatalyst composition (C-2) prepared in Reference Example 5 was used instead of the photocatalyst composition (C-1) prepared in Reference Example 4. (E-2) was obtained.
As a result of measuring the adhesion of this sample (E-2), both the Scotch tape test and the scratch test were good, and there was no peeling. However, both the antibacterial and antifungal properties were poor (x). Furthermore, when the antifouling performance was evaluated, the result was poor (x).
Moreover, the external appearance change in the weather resistance test of this sample (E-2) was a bad result (x).

[Comparative Example 2]
The same operation as in Example 1 was performed except that a commercially available photocatalyst coating liquid ST? K03 (manufactured by Ishihara Sangyo Co., Ltd.) was used instead of the photocatalyst composition (C-1) prepared in Reference Example 4. A functional aluminum building material sample (E-3) was obtained.
The film formability of this sample (E-3) was poor, cracked, and a film worthy of evaluation was not obtained.

[Comparative Example 3]
Instead of applying the commercially available photocatalyst coating liquid ST-K03 (manufactured by Ishihara Sangyo Co., Ltd.) in place of the photocatalyst composition (C-1) prepared in Reference Example 4 so that the dry film thickness is 0.3 μm. Performed the same operation as Example 1 and obtained the functional aluminum building material sample (E-4).
As a result of measuring the adhesion of this sample (E-4), both the Scotch tape test and the scratch test were good, and there was no peeling. Moreover, both antibacterial and antifungal properties were good (◯). Furthermore, when the antifouling performance was evaluated, it was very good (◯).
However, the appearance change in the weather resistance test of this sample (E-4) was very bad (×).

  The present invention is a functional aluminum building material that can be easily coated, has excellent antibacterial and antifungal properties, decomposes the causative substances by the photocatalytic action and penetrates the walls and the like, and has self-cleaning properties It can utilize suitably for etc.

FIG. 1 is a graph showing the results of measuring the particle size distribution of TKS251 (commercially available titanium oxide organosol) before modification using a wet particle size analyzer. FIG. 2 is a view showing the results of measuring the particle size distribution of the modified photocatalyst organosol (A-1) obtained by modifying TKS-251 in Reference Example 4 using a wet particle size analyzer. . 3A is a TEM photograph of a cross section of the test plate (D-1) having a photocatalyst-containing coating film obtained in Reference Example 4. FIG. FIG. 3B is an illustration of FIG. 4A is a TEM photograph of a cross section of an epoxy resin (D-2) having a photocatalyst-containing coating film obtained in Reference Example 4. FIG. FIG. 4B is an illustration of FIG. Fig.5 (a) is the photograph which expanded a part of TEM photograph of Fig.4 (a). FIG. 5B is an illustration of FIG. 6A is a TEM photograph of a cross section of an epoxy resin (D-3) having a photocatalyst-containing coating film obtained in Reference Example 5. FIG. FIG. 6B is an illustration of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Modified photocatalyst particle 2 Photocatalyst containing film | membrane 3 Acrylic urethane film | membrane 4 Titanium oxide which is a pigment 5 Epoxy resin 5 (b) The enlarged view in the boundary part of the modified photocatalyst particle phase 1 and the binder phase 7 which does not contain modified photocatalyst particles 5 (b) 6 embedded epoxy resin 7 binder phase not containing modified photocatalyst particles 8 alkyl group-containing silicone

Claims (18)

  An aluminum building material provided with a coating containing a photocatalyst (a) and a binder component (B), wherein the concentration of the photocatalyst (a) in the coating increases from the surface in contact with the aluminum or aluminum alloy substrate toward the exposed surface. This is a functional aluminum building material.   An aluminum building material provided with a film containing a photocatalyst (a) and a binder component (B), wherein the concentration of the photocatalyst (a) in the film is in contact with the anodized film formed on the aluminum or aluminum alloy substrate Functional aluminum building material characterized in that it becomes higher toward the exposed surface.   The functional aluminum building material according to claim 1, wherein the film is formed from a photocatalyst composition (C) containing a photocatalyst (a) and a binder component (B). The photocatalyst (a) is a triorganosilane unit represented by the formula (1), a monooxydiorganosilane unit represented by the formula (2), a dioxyorganosilane unit represented by the formula (3), and Modified photocatalyst modified with at least one modifier compound (b) selected from the group consisting of compounds having at least one structural unit selected from the group consisting of methylene fluoride (—CF ₂ —) units ( It is A), The functional aluminum building material in any one of Claims 1-3 characterized by the above-mentioned.
R ₃ Si- (1)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group)
_{- (R 2 SiO) - (} 2)
(In the formula, R is as defined in formula (1).)
(In the formula, R is as defined in formula (1).) The functional aluminum building material according to any one of claims 1 to 4, wherein the binder component (B) contains a phenyl group-containing silicone (BP) represented by the following formula (4).
^{_{R 1 p R 2 q X r}} SiO (4-p-q-r) / 2 (4)
(In the formula, each R ¹ represents a phenyl group, and each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or Represents a branched alkenyl group having 2 to 30 carbon atoms;
X represents a hydrogen atom, a hydroxyl group, a C1-C20 alkoxy group, a C1-C20 acyloxy group, an aminoxy group, a C1-C20 oxime group, and a halogen atom each independently. And p, q, and r are 0 <p <4, 0 ≦ q <4, 0 ≦ r <4, and 0 <(p + q + r) <4, and 0.05 ≦ p / (p + q) ≦ 1 is there. ) The functional aluminum building material according to claim 5, wherein the phenyl group-containing silicone (BP) is a phenyl group-containing silicone (BP1) not represented by an alkyl group represented by the following formula (5).
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein R ¹ represents a phenyl group. X is independently a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, and s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.) The functional aluminum building material according to claim 5 or 6, wherein the binder component (B) further contains an alkyl group-containing silicone (BA) represented by the following formula (6).
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. And u and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.) The binder component (B) contains a phenyl group-containing silicone (BP1) not containing an alkyl group represented by formula (5) and an alkyl group-containing silicone (BA) represented by formula (6). The functional aluminum building material as described in any one of Claims 1-4 characterized by the above-mentioned.
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein, R ¹ represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. Represent.
u and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4. ) The alkyl group-containing silicone (BA) has a monooxydiorganosilane unit (D) represented by the formula (7) and a dioxyorganosilane unit (T) represented by the formula (8). The functional aluminum building material according to claim 7 or 8.
— (R ² ₂ SiO) — (7)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Represents an alkenyl group of
(In the formula, R ² is as defined in formula (7).)   The functional aluminum building material according to any one of claims 7 to 9, wherein the functional aluminum building material is a film having a phase separation structure for the phenyl group-containing silicone (BP) and the alkyl group-containing silicone (BA).   The functional aluminum building material according to claim 10, wherein the photocatalyst (a) is present in the alkyl group-containing silicone (BA) phase.   The functional aluminum building material according to claim 4, wherein the number average particle diameter of the modified photocatalyst (A) is 400 nm or less. The functional aluminum building material according to claim 4, wherein the modifier compound (b) is a Si-H group-containing silicon compound (b1) represented by the formula (9).
H _x R _y SiO _{(4-xy) / 2} (9)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group, where x and y are 0 <x <4, 0 <Y <4 and (x + y) ≦ 4.) The Si-H group-containing silicon compound (b1) is a mono-Si-H group-containing compound represented by the formula (10), a Si-H group-containing compound represented by the formula (11), a formula (12) The functional aluminum building material according to claim 13, wherein the functional aluminum building material is at least one compound selected from the group consisting of H silicones represented by:
(In the formula, each R ³ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a carbon number of 5 to 20). A cycloalkyl group, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, a phenyl group, or a siloxy group represented by the formula (13).
—O— (R ⁴ ₂ SiO) _m —SiR ⁴ ₃ (13)
(In the formula, each R ⁴ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number of 1 to 1. 30 represents a fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a phenyl group, and m is an integer, and 0 ≦ m ≦ 1000.
H— (R ³ ₂ SiO) _n —SiR ³ ₂ —H (11)
(In the formula, R ³ is as defined in formula (10). N is an integer and 0 ≦ n ≦ 1000.)
(R ³ HSiO) _a (R ³ ₂ SiO) _b (R ³ ₃ SiO _1/2 ) _c (12)
(Wherein R ³ is as defined in formula (10), a is an integer of 1 or more, b is an integer of 0 or more, (a + b) ≦ 10000, and c is 0 or 2) Provided that when (a + b) is an integer of 2 or more and c = 0, the H silicone of the formula (12) is a cyclic silicone, and when c = 2, the H silicone of the formula (12) Is a chain silicone.)   The functional aluminum building material according to claim 1, wherein the binder component (B) in the coating forms a phase separation structure.   3. The functional aluminum building material according to claim 1, wherein the functional aluminum building material exhibits photocatalytic activity when irradiated with light having energy higher than the band gap energy of the photocatalyst (a) contained in the coating.   By irradiating light with energy higher than the band gap energy of the photocatalyst (a) contained in the film, at least a part of the organic groups bonded to silicon atoms existing in the vicinity of the photocatalyst (a) particles are hydroxyl groups and The functional aluminum building material according to any one of claims 4, 5, 7, and 8, wherein the functional aluminum building material is substituted with a siloxane bond.   A photocatalyst composition (C) comprising a photocatalyst (a) and a binder component (B), wherein the coating film according to claim 1 or 2 is formed. Stuff.