JP3523787B2 - Outdoor building materials with photocatalytic layers - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to the antimicrobial, antifungal, anti-fouling, deodorization, by have a photocatalyst layer can be exhibited over a long period of time the effect of such air purification, suitable for outdoor use
Building materials . More specifically, it is possible to form a highly durable photocatalyst layer on the organic surface of the base material, whereby
The present invention relates to a technique that can be applied to various fields such as exterior materials for construction and various molded products that have a problem in durability even if a photocatalyst layer is formed because a surface portion of a substrate is made of an organic material.

[0002]

_2. Description of the Related Art Semiconductors having a photocatalytic action represented by TiO ₂ are antibacterial, antifungal, antifouling, and antifouling due to the photocatalytic action.
It has been conventionally known that it has a deodorizing effect, and in recent years, various materials utilizing these effects have been researched and developed. For example, Japanese Unexamined Patent Publication (Kokai) No. 2-6333 discloses an antibacterial powder in which antibacterial metal such as copper and zinc is supported on the surface of titanium oxide particles, and this powder should be blended with resin, rubber, glass and the like. An antibacterial composition can be obtained by a known method, and as well as an antibacterial treatment of electric appliances, furniture furniture, upholstery materials, packaging materials such as foods, etc., as an antibacterial agent for environmental hygiene facilities and equipment. It teaches that the above powders can be utilized.

In Japanese Patent Laid-Open No. 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 the substrate can prevent the propagation of germs and mold. Further, in International Publication WO96 / 13327, a film thickness of 0.02 to 0.2 is formed on a translucent substrate such as a glass plate.
Described is a titanium oxide photocatalyst structure formed with a pre-coated thin film made of a SiO ₂ thin film having a thickness of about μm and a titanium oxide thin film having a thickness of about 0.1 to 5 μm with a linear light transmittance of 50% or more for light having a wavelength of 550 nm. There is.

[0004]

Titanium oxide is generally used as a photocatalyst as described above, but products and parts coated with this titanium oxide can be used outdoors in an environment where light with a wavelength of about 400 nm or less exists. When used in, the photocatalytic action of active substances such as OH radicals generated by oxidation of water in the air and O ₂ ^- or HO ₂ radicals generated by reduction of oxygen in the air causes antibacterial action. Since it exhibits various functions such as antifouling and purification effects, it is being used in a wide range of fields. However, there is no problem when using a photocatalyst film or photocatalyst particles supported on an inorganic substrate, but when some photocatalyst film or photocatalyst particles are generally supported on an organic substrate except some organic materials. Is
Since the active substance generated by the photocatalytic action invades the surface of the organic base material, various problems occur.

In the case of the titanium oxide photocatalyst structure described in WO 96/13327, since an inorganic base material such as a glass plate is used, it is possible to use an inorganic material by photocatalytic action without a precoat thin film such as a SiO ₂ thin film. The substrate is not attacked. In this photocatalyst structure, the precoat thin film is used for the purpose of preventing this diffusion because the photocatalytic activity of the titanium oxide thin film is inhibited by the alkaline component such as sodium diffusing from the base material.
No mention is made of the erosive action by the active substance generated by the photocatalytic action as described above.

Even if the above-mentioned pre-coated thin film is formed on the organic base material, if the thickness is about 0.02 to 0.2 μm, the photocatalytic action of the titanium oxide photocatalytic film formed on the precoated thin film is generated. -The penetration of OH radicals cannot be prevented and the surface of the organic base material is decomposed. Further, at the stage of forming the photocatalyst film, a large number of fine cracks are generated in the photocatalyst film due to shrinkage during the heat curing step, and a large number of fine cracks are also generated in the precoat thin film following the cracks. Even if the photocatalyst film formation method is changed so that many cracks do not occur in the precoat thin film, the photocatalyst film and the precoat thin film may be partially chipped due to deterioration with time, distortion, projection collision or impact, etc. I will end up. When such cracks or chips occur, even if the thickness of the precoat thin film is a little thick, for example, about 1 μm which can be formed by the dip coating method which is a standard film forming method, the active substance is the surface of the organic base material. Reaches the department,
The decomposition cannot be prevented.

[0007] Even if such decomposition occurs, it is not a big problem in applications where the expected life is 1 year or less in an outdoor environment, but when a photocatalyst is coated on a member that requires longer durability. , Various problems occur. Specifically, when the surface portion of the organic base material is decomposed, both the intermediate layer and the photocatalyst layer existing thereon lose the scaffold, and thus fall off. In addition, it not only loses the desired function (antifouling property, antibacterial property, deodorizing property, etc.) that utilizes the photocatalytic action, but also reduces the surface gloss and creates a powder blown state.
The original appearance and design are lost.

Therefore, a basic object of the present invention is to solve the above-mentioned problems, and to exert the effects of antibacterial, antifungal, antifouling, deodorant, air purification, etc. stably over a long period of time. An object is to provide a building material having a layer and used outdoors . Furthermore, the object of the present invention is to produce a large number of fine cracks in the photocatalyst layer and the intermediate layer thereunder during the production stage, and to a part of these films due to deterioration with time, distortion, projection collision or impact, etc. Even if occurs, the photocatalytic action does not extend to the surface of the underlying organic base material in the long-term use in an environment where light with a wavelength of about 400 nm or less exists, and the photocatalyst layer remains on the organic base material forever. Another object of the present invention is to provide a photocatalyst film structure that can be stably maintained.

[0009]

In order to achieve the above object, according to the present invention, an organic surface of a substrate and a coating material are applied.
Particle size 5 nm to 1 at a ratio of 1 to 100% by weight with respect to the base material
Is it a thin film in which photocatalytic particles made of TiO _{2 of} μm are dispersed?
And a photocatalyst layer as a surface layer having an average film thickness of 0.05 to 10 μm, an intermediate layer of a material that is not attacked by photocatalysis is interposed, and the distance between the organic surface and the photocatalyst layer. The construction material used outdoors is provided with a photocatalytic layer having a thickness of 3.2 to 10 μm . According to an even more specific aspect, the substrate
1-100% by weight of organic surface and paint base
Touch light consists of TiO ₂ particle size 5nm~1μm in percentage of
It is formed from a thin film in which medium particles are dispersed, and has an average film thickness of 0.
Between the photocatalyst layer as a surface layer having a thickness of 05 to 10 μm
Is made of a material that is not attacked by photocatalysis and cracks
Or intermediate structure with pinhole or porous structure
The layer is interposed, and the distance between the organic surface and the photocatalyst layer is
It has a photocatalyst layer characterized by having a thickness of 3.2 to 10 μm.
A building material for outdoor use is provided. Here, the organic surface of the substrate, when the substrate itself of the product or member is made of an organic material, the surface, by the appropriate means such as coating, impregnation, lamination on the surface of the substrate made of any material When a film of an organic material is formed, it means the surface of the film. The photocatalyst layer means a layer exhibiting a photocatalytic action, and is a thin film containing (supporting and / or containing) TiO ₂ having a photocatalytic action. An inorganic binder, particularly silica, is preferably used as a binder for a thin film containing semiconductor particles, and an inorganic material containing silica as a main component is also preferably used as the intermediate layer.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the film structure of organic base material / intermediate layer / photocatalyst layer, the optimum range of the film thickness of the intermediate layer and the distance between the organic base material and the photocatalyst layer have been conventionally considered from the viewpoint of durability. Nothing was shown about. Therefore, the present inventors have made various studies on these film thicknesses and intervals. As a result, even in the long-term use in an environment such as outdoors exposed to light having a wavelength of 400 nm or less, the important point of exhibiting long-term durability without damaging the organic base material is that the physical properties of the organic base material and the photocatalyst layer are physical. I found that there was an interval. That is, when used for a long period of time in an environment where light with a wavelength of about 400 nm or less exists, such as outdoors, OH radicals generated by oxidation of water in the air due to photocatalytic action and reduction of oxygen in the air Active substances such as O ₂ ⁻ have a function of decomposing organic substances within their movable distance range. The movement distance is approximately 3. under an outdoor environment.
It was confirmed to be 2 μm or less. Hereinafter, description will be given with reference to the accompanying drawings.

FIG. 1 schematically shows the basic film structure of organic substrate 1 / intermediate layer 2 / photocatalyst layer 3. Generally, when the heat curing step is included in the formation of the photocatalyst layer 3, a large number of fine cracks are generated along with the curing shrinkage of the photocatalyst layer 3, and the fine cracks are also formed in the intermediate layer 2 in accordance with the shrinkage. Occurs. When the cross section is observed with an electron microscope, the cross section structure is roughly as shown in FIG. In FIG. 2, reference numeral 4
Indicates a crack that has occurred, and the organic base material 1 in this portion is exposed. Even if such a crack 4 does not occur in the manufacturing stage, the photocatalyst layer 3 and the intermediate layer 2 are partially chipped due to deterioration or distortion over time during long-term use, collision or impact of protrusions, and The organic base material 1 is exposed.

When a product or member having a film structure in such a state is used for a long period of time, dew condensation water is likely to collect in the crack 4. Water in the air also exists in this portion. In this way, when water 5 is present in the crack 4 as shown in FIG. 3, the .OH radicals generated by the photocatalytic layer 3 receiving light and exhibiting a photocatalytic action are likely to move in the water. Conceivable. As a result, as shown in FIG. 4, the exposed surface of the organic base material 1 is attacked by the above-mentioned OH radicals, and as time passes, the surface portion of the organic base material 1 is mainly decomposed as shown in FIG. It progresses along the interface with the layer 2, and finally the intermediate layer 2 and the photocatalyst layer 3 come off. As a result of earnest research on such a phenomenon, the present inventors determined whether or not the exposed surface portion of the organic base material 1 is attacked by the distance d between the surface of the organic base material 1 and the photocatalyst layer 3. It was found that the value was attached and the value was critical. That is, when the distance d is 3.2 μm as a boundary, the surface portion of the organic base material 1 is corroded when the distance d is less than 3.2 μm, and is not corroded when the distance d is 3.2 μm or more. From this, it is considered that the critical migration distance of the · OH radical under the above conditions is around 3.2 μm or less.

The distance d does not necessarily mean the film thickness of the intermediate layer 2. For example, the surface of the intermediate layer 2 may be uneven, and in that case, the minimum thickness of the intermediate layer is 3.2 μm.
It should be at least m. Further, the intermediate layer 2 needs to be formed of a material that is not affected by the photocatalytic action, but the organic substrate 1
Whether or not the surface portion of P is attacked depends on the distance d between it and the photocatalyst layer 3. Therefore, any intermediate layer having a structure capable of keeping this distance d constant may be used. Therefore, the intermediate layer 2 may have a large number of cracks and pinholes, or may have a porous structure. Examples of the intermediate layer which is not affected by the photocatalytic action are silica, alumina, indium oxide, zirconium oxide, SiO ₂ + MO _X (MO _X is P ₂ O ₅ , B ₂
At least one metal oxide such as O ₃ , ZrO ₂ and Ta ₂ O ₅ ) or nitride, oxynitride, sulfide, carbide, ceramics such as carbon, and thin films of various inorganic materials such as metal are preferably used. be able to. Further, a thin film of an organic material such as a silicone resin or polytetrafluoroethylene which is not or very hardly attacked by a photocatalytic action can also be used.

As described above, by setting the distance d between the surface of the organic base material 1 and the lower end of the photocatalyst layer 3 (or photocatalyst particles) to be 3.2 μm or more, the organic group can be generally used even if it is used for a long period of time. The surface of the material is not decomposed, the intermediate layer and the photocatalyst layer above it can be stably held, and the effects of antibacterial, antifungal, antifouling, deodorizing, air purification, etc. are stable over a long period of time. It will be possible to demonstrate. However, when used outdoors, environmental conditions such as the amount of solar radiation, rainfall, temperature, and humidity may overlap at worst depending on the location and type of usage, and the distance traveled by OH radicals may vary. Therefore, the distance d between the surface of the organic base material and the lower end of the photocatalyst layer (or photocatalyst particles) is more preferably 3 . 5μ
It is desirable that it is m or more. On the other hand, the upper limit of this distance d is not particularly limited, for example, about several tens of μm,
Alternatively, it may be more than 10 μm depending on the object to be applied, but in view of productivity and economy, and flexibility when the object to be applied is a sheet-like object , 10 μm or less is suitable.

The material of the organic base material or the organic coating formed on the surface of any base material is ABS resin, styrene-acrylonitrile copolymer (SAN), fibrin acetate, fibrin butyacetate, cresol resin, fibrin nitrate. , Casein, epoxy resin, melamine resin, polyamide, polycarbonate, trifluoroethylene resin, diallyl phthalate resin,
Resin materials composed of polyethylene, phenol resin, acrylic resin, acetal resin, polypropylene, polystyrene, polyurethane, vinyl acetate resin, vinyl chloride resin, vinylidene chloride resin, silicon resin, urea resin, unsaturated polyester resin, fluororesin, etc. An example is a coating film. Further, wood or paper made of cellulose or the like, or rubber material can also be used. Further, as the base material for forming the organic coating, various metals such as aluminum and iron or various metals surface-treated to impart corrosion resistance such as anodic oxidation, ceramics and synthetic resins can be used. Not limited to. Further, the form of the base material may be a product such as a shape member, a panel, a sheet, a film, or a molded product of various shapes, a part or a member, and is not limited to a particular one.

As a method of forming the intermediate layer on the surface of the base material as described above, various conventionally known methods can be applied and are not limited to specific methods. For example, when the intermediate layer is formed of ceramics, a coating material in which ceramics fine particles or their precursors (metal alkoxide, metal halide, etc.) are dispersed in an organic solvent is spray-coated or rolled according to its viscosity. Coating on the substrate surface by an appropriate method such as a coating method, a dip coating method, a spin coating method, a flow coating method,
The method of heating and evaporating the solvent and curing the solvent is advantageous in terms of productivity and cost. On the other hand, when the intermediate layer is formed of metal, a metal foil laminating method, a plating method, or the like can be adopted, and various coating methods can be adopted when an organic material such as silicone resin or polytetrafluoroethylene is used.

The semiconductor having a photocatalytic action must be a semiconductor having a relatively large electron-hole mobility and a photocatalytic action , and TiO ₂ is particularly preferable.
Moreover, silver, together with a semiconductor having such a photocatalytic action,
If an antibacterial metal or an antibacterial metal compound such as copper or zinc is allowed to coexist, for example, if dispersed in the photocatalyst layer or attached to the surface of the photocatalyst layer, the antibacterial and antifungal properties can be obtained even at night. Will be maintained.

The semiconductor, antibacterial metal or antibacterial metal compound having a photocatalytic action may be in the form of individual fine particles, or the surface of semiconductor fine particles having a photocatalytic action (hereinafter referred to as photocatalytic fine particles) may be an antibacterial metal or antibacterial substance. Metal compounds are partially (or some particles may be wholly)
Adhesive form, inorganic fine particles such as silica partially adhere to the surface of photocatalyst fine particles, inorganic fine particles and antibacterial metal or antibacterial metal compound partially adhere to the surface of photocatalyst fine particles Various forms such as a form, a form in which the inorganic fine particles to which the antibacterial metal or the antibacterial metal compound is attached are attached to the surface of the photocatalyst particles, can be adopted.

As a method for coating a semiconductor having a photocatalytic action, various methods such as a sputtering method, a thermal spraying method, a laser ablation method, a sol-gel method and a plating method can be used. Photocatalyst fine particles or their precursors, or further fine particles of an antibacterial metal or an antibacterial metal compound are dispersed in a different coating material, and the resulting composition is coated on a substrate by coating and drying, followed by heating and curing. preferable. The photocatalyst film can be formed by the various coating methods described above when the base material and the coating film can withstand high temperatures, but it is difficult to heat the photocatalyst film to a high temperature when the resin material is poor in heat resistance. In that case, a method may be adopted in which the photocatalyst fine particles are dispersed in a suitable coating material, and the coating is performed by applying and drying this on a base material. In addition, the base of the coating material (inorganic binder) in which photocatalyst fine particles are dispersed
Is the same as the film forming component of the paint for the intermediate layer as described above, the effect of further improving the adhesion between the intermediate layer and the photocatalyst layer can be obtained.

The thickness of the photocatalyst layer coated on the intermediate layer is suitably 0.05 to 10 μm. If the film thickness is thick, the photocatalytic activity can be kept high for a long period of time, and there is an advantage that coloring due to light interference is reduced.
When the film thickness exceeds m, the photocatalyst film is likely to be peeled from the base material, and it is not preferable in terms of productivity and cost.
In particular, after coating the photocatalyst film, peeling is likely to occur during assembly or construction. A film having such a thickness can maintain sufficiently high transparency without causing problems such as whitening on the photocatalyst film. Particularly when used outdoors, it is preferable to set the average film thickness to 0.5 μm or more in consideration of wear resistance.

In the case of a coating method in which photocatalyst fine particles are dispersed in a coating material and applied, the proportion of the photocatalyst fine particles to be mixed is 1 to 100% by weight (here, 100% by weight means the photocatalyst fine particles). Is equivalent to the weight of the paint base). If it is less than 1% by weight, the amount of the photocatalyst fine particles exhibiting a photocatalytic action is insufficient, and thus a sufficient photocatalytic action cannot be obtained. On the other hand, if it exceeds 100% by weight, there is no problem in exhibiting the photocatalytic action. The mechanical properties of the membrane are significantly reduced.

The particle diameter of the photocatalyst fine particles used is from 5 nm to
1 μm, preferably 10 nm to 300 nm is suitable. If the particle size is smaller than 5 nm, the band gap becomes large due to the quantum size effect, and there is a problem that the photocatalytic action cannot be obtained unless under illumination such as a high-pressure mercury lamp that emits short-wavelength light. Further, if the particle size is too small, there arises a problem that the handling is difficult and the dispersibility in the paint is poor. From the viewpoint of handleability, a particle size of 10 nm or more is preferable. On the other hand, the particle size is 1 μm
If it exceeds, since relatively large photocatalyst fine particles are present on the material surface, the smoothness of the surface becomes poor,
Further, the particles exposed on the surface of the material are likely to fall off. Considering the smoothness of the material surface and the like, a particle size of 300 nm or less is preferable.

To deposit the antibacterial metal or the antibacterial metal compound on the photocatalyst layer, a solution of an appropriate compound containing an antibacterial metal such as silver or copper such as silver nitrate or copper chloride is prepared,
One method is to immerse the base material coated with the intermediate layer and the photocatalyst layer in the solution, and irradiate it with ultraviolet rays from an ultraviolet lamp or a black light to produce antibacterial metal by the action of electrons generated by the photocatalytic action of the photocatalyst layer. Ions or antibacterial metal compound ions are reduced and the antibacterial metal or antibacterial metal compound is deposited on the surface of the photocatalyst layer. In this case, the amount of the antibacterial metal or the antibacterial metal compound deposited depends on the amount of the antibacterial metal ion in the solution, that is, the concentration of the prepared solution, the concentration of the reducing agent such as alcohol or EDTA added to the solution, or the ultraviolet irradiation. It can be controlled by time.

As another method, there is a method in which the solution is applied onto a substrate coated with an intermediate layer and a photocatalyst layer by an appropriate method such as spraying, and then the solution is irradiated with ultraviolet rays. In this method, the antibacterial metal or the antibacterial metal is adjusted depending on the amount of the antibacterial metal ion in the solution, that is, the concentration of the prepared solution, the concentration of the reducing agent such as alcohol or EDTA added to the solution, the coating amount, or the ultraviolet irradiation time. The amount of compound deposited can be controlled. In any of the above methods, if the entire surface of the photocatalyst layer is coated with the antibacterial metal or the antibacterial metal compound, the photocatalytic action cannot be expressed, and therefore the amount of precipitation is controlled so that the entire surface is not covered. There is a need.

[0025]

EXAMPLES The effects of the present invention will be specifically described below with reference to Examples and Comparative Examples, but it goes without saying that the present invention is not limited to the following Examples.

Examples 1 to 10 and Comparative Examples 1 to 15 A silicon coating agent (manufactured by Nippon Soda Co., Ltd.,
Vistorator L NSC-200A , organic solvent type silicone
Con-acrylic containing coating agent, solid content 10 wt
% ) By a spray method and cured by heating at 90 ° C. for 30 minutes to form silicon-based intermediate layers of various thicknesses shown in Table 1. On top of this, a photocatalytic titanium oxide coating agent (manufactured by Nippon Soda Co., Ltd., VISTRATER L NS
C-200C , organic solvent based titanium oxide containing coating
Agent, solid content 8 wt% ) by spray method,
The coating was heated at 120 ° C. for 30 minutes for curing to form photocatalyst layers having various film thicknesses shown in Table 1. The film portion of the sample thus obtained was scratched with an iron brush and cracked as shown in FIG.
I put.

Deterioration accelerated test: Deterioration of the sample was accelerated using a Dew Panel Weather Meter (DPWL-5R manufactured by Suga Test Instruments Co., Ltd.) by irradiation with an ultraviolet fluorescent lamp (60 ° C., 4 hours, irradiance 30 W / m).
² nm) and condensation (50 ° C, 4 hours) for 250 hours, 5
It was carried out by repeating 00 hours or 1,000 hours. By observing the cross-sectional structure of the sample after the test with an electron microscope, the presence or absence of deterioration of the coating film (resin) portion at the crack portion as in the cross-sectional model schematically shown in FIG. 7 was examined. The results are summarized in Table 1. The meaning of each symbol in Table 1 is as follows. ◯: No decomposition of coating film part. Δ: A slight decomposition is observed in the coating film part. X: There is decomposition of the coating film part.

[0028]

[Table 1] As shown in Table 1, the minimum thickness of the intermediate layer is 3.2 μm.
It can be clearly understood whether the coating film (resin) part is decomposed or not depending on whether it is less than or more than that.

[0029]

INDUSTRIAL APPLICABILITY As described above, in the building material having a photocatalyst layer according to the present invention to be used outdoors, a large number of fine cracks are generated in the photocatalyst layer and the intermediate layer below the photocatalyst layer during the production stage, and Even if a part of these films is chipped due to deterioration, distortion, collision of bumps, impact, etc., the photocatalytic action will not cause the photocatalytic action as a base in long-term use in an environment where light with a wavelength of about 400 nm or less exists, such as outdoors. The photocatalytic layer does not extend to the surface of the organic base material and the photocatalyst layer is kept stable on the organic base material forever, and the effects of antibacterial, antifungal, antifouling, deodorizing, air purification, etc. are stable over a long period of time. Can be demonstrated. Further, by applying the photocatalyst layer to a variety of organic substrate surface, it is possible to maintain the photocatalytic function for a long period of time, sash, panel material, not only building exterior material such as a screen door, each species profiled The photocatalytic function can be used in a wide range of fields.

[Brief description of drawings]

FIG. 1 is a schematic partial cross-sectional view showing a basic film structure of a building material having a photocatalyst layer of the present invention.

FIG. 2 is a schematic partial cross-sectional view showing a state in which cracks have occurred in the photocatalyst layer and the intermediate layer of the building material after manufacturing.

[Fig. 3] ・ OH through water existing in cracks of building materials
FIG. 6 is a schematic partial cross-sectional view for explaining a state in which radicals move.

FIG. 4 is a schematic partial cross-sectional view for explaining a state where decomposition of an organic base material surface portion of a building material occurs.

FIG. 5 is a schematic partial cross-sectional view for explaining a state in which the surface portion of the organic base material of the building material is further decomposed.

FIG. 6 is a schematic partial cross-sectional view of samples prepared in Examples and Comparative Examples.

FIG. 7 is a schematic partial cross-sectional view showing a decomposed state of a coating film portion of a sample after a deterioration acceleration test in Examples and Comparative Examples.

[Explanation of symbols]

1 organic base material 2 Middle class 3 Photocatalyst layer 4 cracks 5 water

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideo Fukui 4016 Mikkaichi, Kurobe City, Toyama Prefecture (72) Inventor Nobuyuki Bansaku 13 Kamikoizumi, Namerikawa City, Toyama Prefecture (72) Nobuyuki Nakata 1300, Horikiri, Kurobe City, Toyama Prefecture (72) Inventor Kazuo Aikawa 526-2 Kamikoizumi, Namerikawa-shi, Toyama Prefecture (72) Inventor Toshiji Yoneya 335-8 Doujin-ku, Kurobe-shi, Toyama Prefecture (72) Toshiji Sato Tenjinno Shin552-2, Uozu-shi, Toyama Prefecture ( 72) Inventor Akira Fujishima 710 Nakamaruko, Nakahara-ku, Kawasaki-shi, Kanagawa 5 (72) Kazuhito Hashimoto 2073 Iijima-cho, Sakae-ku, Yokohama-shi, Kanagawa 2 New City Hongodai D Bldg. 213 (56) Reference Japanese Patent Laid-Open No. 7- 171408 (JP, A) JP 9-57911 (JP, A) JP 9-313887 (JP, A) JP 11-52487 (JP, A) JP 11-52491 (JP, A) JP 2000-1314 (JP, ) Patent flat 11-291408 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB name) B32B 1/00 - 35/00 B01J 21/00 - 37/36

Claims (6)

(57) [Claims] 1. A paint base in an organic surface of a base material and in a paint.
In the ratio of 1 to 100% by weight, the particle size is 5 nm to 1 μm.
Formed from a thin film in which TiO ₂ photocatalyst particles are dispersed
An intermediate layer of a material that is not affected by photocatalytic action is interposed between the photocatalyst layer as a surface layer having an average film thickness of 0.05 to 10 μm, and the distance between the organic surface and the photocatalyst layer is 3 mm. A building material used outdoors having a photocatalyst layer having a thickness of 2 to 10 μm . 2. A paint base in an organic surface of a base material and in a paint.
In the ratio of 1 to 100% by weight, the particle size is 5 nm to 1 μm.
TiO ₂ Formed from a thin film in which photocatalytic particles consisting of
As a surface layer having an average film thickness of 0.05 to 10 μm
Not affected by photocatalytic action between all photocatalytic layers
Structures or cracks or pinholes made of material
Has an intermediate layer having a porous structure, and is exposed to the above-mentioned organic surface by light contact.
The distance between the medium layer and the medium layer is 3.2 to 10 μm
A building material used outdoors having a photocatalyst layer. 3. A process according to claim 1 the distance between the organic surface and the photocatalyst layer is characterized in that it is a 3.5~10μm also
Is the building material described in 2 . Wherein said intermediate layer is any one of claims 1 to 3, characterized in that an organic thin film made of an inorganic thin film or a silicone resin or polytetrafluoroethylene
The building material described in paragraph . 5. The building according to claim 1, wherein the organic surface is a surface of an organic base material or a surface of a film of an organic material formed on the surface of the base material. Materials. 6. The average thickness of the photocatalyst layer is 0.5 to 10.
Building material according to any one of claims 1 to 5, characterized in that it is [mu] m.