JP3956598B2 - Photocatalyst and method for producing photocatalyst - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a photocatalyst having a room temperature curable photocatalyst film.andThe present invention relates to a method for producing a photocatalyst body.
[0002]
[Prior art]
  It is known to use a photocatalytic film for deodorizing, antifouling and / or antibacterial.
[0003]
  When the photocatalyst film is irradiated with ultraviolet rays and absorbs the light energy, electrons and holes are generated in the semiconductor that constitutes the photocatalyst film and exhibits a photocatalytic action. Electrons and holes react with oxygen and water on the film surface to generate active oxygen and other active radicals, and oxidize and reduce components of organic matter such as dirt and odor and decompose them.
[0004]
  Of the substances having photocatalytic activity, titanium oxide is currently most promising. This is because titanium oxide has a remarkable photocatalytic action, is a safe and industrially reasonable price, and can be obtained in a necessary amount.
[0005]
  Recently, attention has been paid to the usefulness of photocatalytic films, and there is an active movement to form photocatalytic films on a wide range of articles such as building materials, lighting fixtures, and lamps.
[0006]
  Although there are various methods for producing a photocatalytic film, a dip method and an ultrafine particle dispersion coating method are generally used.
[0007]
  In the dip method, when the metal alkoxide constituting the photocatalyst film on the substrate, for example, the photocatalyst film is titanium oxide, a coating solution containing titanium alkoxide is applied and baked at a temperature of 400 to 500 ° C. to form the photocatalyst film. It is a method of forming. The photocatalyst film obtained by this production method is durable because of its excellent film strength.
[0008]
  The ultrafine particle dispersion coating method is a method in which a photocatalytic film is obtained by applying a dispersion liquid in which a photocatalytic ultrafine particle such as titanium oxide is dispersed in a solvent made of water, isopropyl alcohol or the like to a substrate and baking it. The photocatalytic film obtained by this production method has high crystallinity and excellent photocatalytic properties.
[0009]
  On the other hand, a photocatalyst using a binder that is curable at room temperature has been developed, and a photocatalyst film can be formed on a non-refractory substrate at a relatively low temperature.
[0010]
[Problems to be solved by the invention]
  If the photocatalyst film obtained by the dip method is not fired at a high temperature for a long time, there is a problem that the crystallinity on the film surface is insufficient and the photocatalytic property is low. Further, when the substrate is a soft glass such as soda lime glass, since the softening temperature of the glass is relatively low, it cannot be fired at a required high temperature, and it is difficult to obtain sufficient photocatalytic properties.
[0011]
  On the other hand, in the photocatalyst film obtained by the ultrafine particle dispersion coating method and the photocatalyst film using the room temperature curable binder, it is difficult to obtain sufficient adhesion of the photocatalyst film to the substrate. In addition, when an organic binder is used, cracks are likely to occur in the binder. Furthermore, cracks occur in the photocatalyst film due to insufficient drying of the underlayer. When cracks occur in this way, there is a problem that the transmittance decreases due to cloudiness.
[0012]
  The present invention provides adhesion strength, photocatalytic actionandAn object of the present invention is to provide a room-temperature curable photocatalyst having high photocatalytic film strength and a method for producing the photocatalyst.
[0013]
[Means for achieving the object]
    The photocatalyst of the invention of claim 1 comprises a substrate; and an oxide of one or more metals selected from the group consisting of Al, Zr, Si, Ti, Zn, Mg, Y, In, Sn, Ta, and Sb. The average particle size is 10-100 nmWithin the range and the average particle size is different to 2 or more typesMetal oxide fine particlesIn a mixed stateA base layer formed on the surface of the substrate, which is bound by a binding material mainly composed of a Si compound;
Metal oxide ultrafine particles having an average particle diameter of 10 to 100 nm made of an oxide of one or more kinds of metals selected from the group consisting of Al, Zr, Si, Ti, Zn, Mg, Y, In, Sn, Ta and Sb And a base layer having at least a porous surface disposed on the surface of the substrate; and an average particle diameter of the metal oxide long fine particles of the base layer A photocatalytic film formed by binding photocatalytic metal oxide ultrafine particles mainly composed of titanium oxide ultrafine particles smaller than the diameter with a room temperature curable binder, and disposed on an underlayer. It is characterized by.
[0014]
  In the present invention and each of the following inventions, the definitions and technical meanings of terms are as follows unless otherwise specified.
[0015]
    <About the substrate>
  The substrate carries a photocatalyst film and is formed not only for a member exclusively for carrying a photocatalyst film but also for other functions not originally intended for carrying a photocatalyst film (hereinafter referred to as “ "Functional body").
[0016]
  Functional bodies include, for example, building materials such as tiles, window glass, and ceiling panels, interior materials such as wallpaper and curtains, kitchen and sanitary equipment, home appliances, lighting equipment, deodorizing or dust collecting filters Various desired members can be used as the substrate.
[0017]
  As the base material, not only refractory materials such as metal, glass, ceramics (including porcelain), earthenware, stone, etc., but also a room temperature curable photocatalytic film is used, and the porous underlayer is also made room temperature curable. By doing so, a flammable material such as a synthetic resin, wood, paper, and fabric, that is, a non-refractory substrate can be used.
[0018]
    <Underlayer>
  The underlayer is interposed between the photocatalyst film and the substrate, and is used for the purpose of improving the adhesion of the photocatalyst film or improving the optical characteristics of the photocatalyst. Therefore, the underlayer is formed on the surface of the substrate before forming the photocatalytic film.
[0019]
  The underlayer used in the present invention has at least a porous surfaceWhenWhen the photocatalyst film is formed on the underlayer, the photocatalyst film enters into the irregularities formed on the surface of the underlayer due to the porosity.
[0020]
  The underlayer is made of a metal oxide of one or more metals selected from the group consisting of Al, Zr, Si, Ti, Zn, Mg, Y, In, Sn, Ta, and Sb, and has an average particle diameter. By binding ultrafine particles of 10 to 100 nm, preferably 10 to 40 nm, with a binder mainly composed of a Si compound,PreferablyThe surface is formed to be porous. This porosity is preferably set in the range of 40 to 90% molar ratio. If the average particle diameter of the metal oxide ultrafine particles exceeds 100 nm, the underlayer tends to become cloudy and the mechanical strength is lowered and becomes brittle.
[0021]
  The metal oxide fine particles in the underlayer have an average particle diameter in the range of 10 to 100 nm and have an average particle diameter different from two or more. For example, metal oxide fine particles having an average particle diameter of 20 nm and metal oxide fine particles having an average particle diameter of 60 nm are mixed. In many cases, the distribution of the particle diameters of the metal oxide fine particles in the average particle diameter can be about ± 5 nm in half width with respect to the average particle diameter. A first particle size group in which the half-value width is normally distributed in the range of 15 to 25 nm before and after, and a second particle size in which the half-value width is normally distributed in the range of 55 to 65 nm before and after the particle size of 60 nm as a peak It consists of a group. However, in the present invention, the half-width particle size distribution range in the average particle size may be narrower or wider than the above example.
[0022]
  The type of metal oxide fine particles in the underlayer may be either one type or a plurality of types. Moreover, when using multiple types of metal oxide fine particles, the type of metal oxide fine particles can be varied for each average particle size, and multiple types of metal oxide fine particles can be used for each average particle size. it can.
[0023]
  In the present invention, the average particle size of the metal oxide fine particles contained in the underlayer is determined by the following method. That is, the cross-section of the photocatalyst was magnified 50,000 times with an electron microscope and photographed, and the particle diameter of the metal oxide fine particles within the range of 5 cm in the obtained electron micrograph was measured from the photograph, Obtain the particle size distribution. The average particle size is defined as the peak particle size in the particle size distribution. If metal oxide fine particles having a plurality of kinds of average particle diameters are mixed in the underlayer, a plurality of peaks appear. This method tends to give a slightly smaller average particle size than the actual average particle size, but generally shows a good correlation.
[0024]
  Thus, since the underlayer is composed of a metal oxide, it generally has transparency, and has good compatibility with a photocatalyst film composed mainly of titanium oxide ultrafine particles described later. The photocatalytic film can be firmly attached to the substrate.
[0025]
  Furthermore, at least the surface of the underlayer is made porous to form an uneven surface.CaseHowever, since the average particle diameter of the metal oxide fine particles is larger than the average particle diameter of the ultrafine titanium oxide particles constituting the photocatalyst film, dents and voids are generated between the metal oxide fine particles. At least this makes the surface porous.
[0026]
  Next, in order to bind the metal oxide fine particles, a binder mainly composed of an Si compound is used. And it adjusts the coating liquid which disperse | distributed the metal oxide microparticles | fine-particles in the solvent containing the binder forming material which forms a binder, and apply | coats this to the surface of expectation, generally 15-300 degreeC The base layer can be formed by firing in the range of preferably 80 to 300 ° C. However, a binder mainly composed of a room temperature curable Si compound can also be used. As a binder mainly composed of a room temperature curable Si compound, for example, a material obtained by adding a curing catalyst to at least one selected from the group consisting of an organomonosilane containing a methyl group and an organosilane oligomer containing a methyl group should be used. Can do. In addition, as a curing catalyst, at least 1 type selected from the group which consists of an acid, an alkali, a zinc compound, a titanium compound, and a zirconium compound, for example can be used. In addition, by adjusting a coating solution in which metal oxide ultrafine particles are dispersed in a binder solution composed of a composition in which polysilazane and an oxidation catalyst are blended in an organic solvent having no OH group, the coating solution is applied on the underlayer, It is also possible to form a base layer by drying. In addition, when forming a base layer using a normal temperature curable binder as mentioned above, it can comprise so that it may harden | cure at 15-100 degreeC. Moreover, as a method for applying the coating solution to the substrate, a spray coating method, a dip coating method, a flow coating method, a roll coating method, a spin coating method, a brush coating method, a sponge coating method, or the like can be employed.
[0027]
  Furthermore, the metal oxide fine particles constituting the underlayer have a refractive index smaller than that of the photocatalyst film, so that the intermediate layer between a substrate having a low refractive index, such as soda lime glass, and a photocatalytic film having a high refractive index is used. By forming a base layer having a refractive index, a refractive index gradient structure can be realized. By adopting the inclined structure, it is possible to reduce the difference in refractive index between the substrate, the underlayer, and the photocatalyst film that are in contact with each other, thereby suppressing the occurrence of optical interference.
[0028]
  Furthermore, the underlayer can be formed in any desired film thickness. For example, an underlayer of 50 nm to several μm can be easily obtained.
[0029]
    <About photocatalytic membrane>
  The photocatalytic material is titanium oxide TiO₂Mainly ultrafine particles. Titanium oxide is currently most promising as a photocatalytic substance because it has a remarkable photocatalytic action and is available in a safe and industrially reasonable price and in a necessary amount.
[0030]
  Titanium oxide has a rutile form and anatase form as its crystal structure. The photocatalytic action is said to be superior to the anatase form. Therefore, in the present invention, it is preferable to use anatase type titanium oxide. However, in reality, it is often formed by mixing rutile form with anatase form, and when using ultrafine particles of titanium oxide, practical photocatalytic action is possible even if both crystal structures are mixed. In the present invention, a mixed mode of both is allowed. Furthermore, the decomposability of organic substances changes depending on the mixing ratio.
[0031]
  Furthermore, in the present invention, photocatalytic metal oxide ultrafine particles other than titanium oxide ultrafine particles may be added as a subcomponent in the photocatalyst film. Other photocatalytic materials include the following. WO₃, LaRhP₃, FeTiO₃, Fe₂O₃, CdFe₂O₄, SrTiO₃, CdSe, GaAs, GaP, RuO₂, ZnO, CdS, MoS₃, LaRhO₃, CdFeO₃, Bi₂O₃, MoS₂, In₂O₃, CdO, SnO₂Etc. These substances can be used alone or in combination.
[0032]
  TiO₂, WO₃, SrTiO₂, Fe₂O₃, CdS, MoS₃, Bi₂O₃, MoS₂, In₂O₃, CdO, etc. have an absolute value of the redox potential in the equivalent electron band larger than the absolute value of the redox potential in the conduction band, so the oxidizing power is greater than the reducing power, and the deodorizing action and prevention by the decomposition of organic compounds. Excellent antifouling or antibacterial effect. Among the above materials, in terms of raw material costs, Fe₂O₃And ZnO is excellent.
[0033]
  Furthermore, in the present invention, the titanium oxide ultrafine particles are used in the form of fine particles having an average particle diameter of 10 nm or less, preferably 4 to 10 nm. The ultrafine particles are preferably fine particles having a shape close to a sphere as much as possible, and having a small variation in particle size and good crystallinity.
[0034]
  Furthermore, the photocatalytic film is formed by binding the photocatalytic metal oxide ultrafine particles mainly composed of the above-described titanium oxide ultrafine particles with a room temperature curable binder. As the room temperature curable binder, for example, a material obtained by adding a curing catalyst to at least one selected from the group consisting of an organomonosilane containing a methyl group and an organosilane oligomer containing a methyl group can be used. In addition, as a curing catalyst, at least 1 type selected from the group which consists of an acid, an alkali, a zinc compound, a titanium compound, and a zirconium compound, for example can be used. In addition, a coating solution in which ultrafine titanium oxide particles are dispersed is prepared in a binder solution composed of a composition comprising polysilazane and an oxidation catalyst in an organic solvent having no OH group. Thus, a photocatalytic film can be formed. Moreover, when forming a photocatalyst film | membrane using a normal temperature curable binder, it can comprise so that it may harden | cure at 15-100 degreeC. In addition, to prepare a coating liquid consisting of photocatalytic metal oxide ultrafine particles, a binder forming material for forming a room temperature curable binder, and a solvent, Any of the various methods described in the description of the above can be adopted.
[0035]
  At this time, the photocatalyst film obtained in this way enters and adheres to the uneven surface of the surface of the underlayer because at least the surface of the underlayer is porous. This structure can be easily formed, for example, by applying a dispersion of a photocatalyst film on an underlayer having a porous surface and drying it.
[0036]
  Furthermore, in order to ensure that the ultrafine particles of titanium oxide enter the irregular surface of the underlayer, a method using mechanical pressure can be applied. In this method, mechanical pressure is applied from above the coating layer of ultrafine titanium oxide particles and pushed into the underlayer.
[0037]
  Furthermore, the photocatalytic film has a film thickness of 100 to 500 nm, preferably in the range of 130 to 200 nm, and optimally about 150 nm, so that the photocatalytic action is exhibited as desired, and the production is easy. And it becomes difficult to produce a crack.
[0038]
  Furthermore, the photocatalyst film is formed by adding an organic dye such as methylene blue to the coating solution, so that the photocatalyst film is colored. Therefore, it is easy to determine the presence and state of the photocatalyst film. Thereby, the application state of the photocatalyst film can be easily observed visually. In addition, once the ultraviolet light is irradiated, the organic dye is decomposed, disappears and becomes transparent, so that the commercial property of the photocatalyst is not deteriorated.
[0039]
    <About the action of the invention>
  In the present invention, since the metal oxide fine particles of the underlayer are mixed with two or more different average particle sizes, the underlayer film becomes dense and the film strength of the underlayer is improved. Since the metal oxide fine particles are exposed and porous irregularities are formed at least on the surface of the underlayer, the photocatalytic film is favorably attached. Therefore, the adhesion strength of the photocatalytic film to the substrate is improved.
[0040]
  The photocatalyst film has photocatalytic metal oxide ultrafine particles mainly composed of ultrafine particles of titanium oxide bound by a room temperature curable binder, so that it can be cured at room temperature. You can get a body.
[0041]
  In addition, since the photocatalyst film is mainly composed of ultrafine titanium oxide particles, a strong photocatalytic action can be obtained.
[0042]
  Furthermore, since the photocatalyst film does not easily cause cracks, the film strength is improved and the adhesion strength to the underlayer is strong.
[0043]
  Furthermore, since the coating liquid in which the photocatalytic metal oxide ultrafine particles mainly composed of titanium oxide are dispersed is deposited on the base layer and obtained by curing the room temperature curable binder, the production is easy.
[0044]
  Furthermore, since a metal oxide such as silicon oxide or aluminum oxide whose refractive index is smaller than that of the photocatalyst film is used as the metal oxide constituting the underlayer, the photocatalyst is formed with a refractive index inclined, and light Generation of interference can be prevented. For this reason, the transmittance | permeability of a photocatalyst film | membrane improves and a highly transparent photocatalyst body is obtained.
[0045]
    Claim2The method for producing a photocatalyst of the invention comprises an oxide of one or more kinds of metals selected from the group consisting of Al, Zr, Si, Ti, Zn, Mg, Y, In, Sn, Ta, and Sb.TheAverage particle sizeButWithin the range of 10-100 nmAnd the average particle size is different to 2 or moreA first coating liquid adjusting step of adjusting a first coating liquid in which metal oxide fine particles are dispersed in a liquid containing a binder forming material that forms a binder mainly composed of an Si compound and a solvent; An undercoat layer disposing step of applying a first coating liquid onto the surface of the substrate and drying to dispose an underlayer having at least a porous surface; an average particle diameter of the metal oxide fine particles of the underlayer A second coating liquid dispersed in a liquid containing a photocatalytic metal oxide ultrafine particle mainly composed of titanium oxide ultrafine particles smaller than the diameter, a binder forming material for forming a room temperature curable binder, and a solvent. A second coating liquid adjusting step for adjusting; and a photocatalyst film disposing step for applying the second coating liquid on the base layer of the substrate and drying to dispose the photocatalytic film. It is a feature.
[0046]
  The present invention provides a production method for producing the photocatalyst according to claim 1.That is, in order to disperse metal oxide fine particles having different average particle sizes of two or more types in a liquid containing a binder forming material and a solvent, metal oxide fine particles having different average particle sizes of two or more types are mixed in advance. After that, it may be dispersed in a liquid containing a binder forming material and a solvent, or may be dispersed sequentially in a liquid containing a binder forming material and a solvent.
[0047]
  The binding material forming material in the first coating liquid may be of any specific composition as long as the binding material mainly composed of the Si compound is formed when the underlayer is formed. As the binder forming material for forming the room temperature curable binder, for example, those described in claim 1 can be used.
[0048]
  The binder forming material in the second coating liquid may have any specific composition as long as it forms a room temperature curable binder when the photocatalytic film is formed. For example, what was described in claim 1 can be used.
[0049]
  In addition, the base may be formed as a functional body that does not have a photocatalytic film, and a base layer and a photocatalytic film may be formed later, or after the base layer and the photocatalytic film are formed in an intermediate stage of the functional body manufacture. A base body in which a functional body is completed may be used.
[0050]
    BookInventionphotocatalystBodythisFunctional bodyInFormationcan do. in this case,Forming at least part of the functional body as a basecan do.
[0051]
  the aboveThe “functional body” is as described in claim 1. AndFunctional bodyCan be applied to all members having some functions.
[0052]
  The “functional body main body” means a part or the whole of the functional body excluding the photocatalytic film. For example, when the functional body is a tile, an ordinary tile portion is referred to as a functional body main body in the present invention. If a photocatalytic film is formed on the front surface of the tile, a photocatalytic film is formed on a part of the functional body main body. Will be formed.
[0053]
  When the functional body is a lamp, the photocatalytic film can form a photocatalytic film on the outer surface of the glass bulb of the lamp. As long as the lamp surrounds the light emitting portion with a glass bulb and includes a wavelength of 400 nm or less, the light emission principle is not limited. For example, it is allowed to be an incandescent bulb or a discharge lamp. In the case of an incandescent lamp, a halogen lamp having a higher color temperature has a higher emission ratio at a wavelength of 400 nm or less than a general lighting lamp. In the case of a discharge lamp, either a low pressure discharge lamp or a high pressure discharge lamp may be used. An example of the low-pressure discharge lamp is a fluorescent lamp. In the case of a fluorescent lamp, if necessary, the phosphor to be used can be selected to appropriately increase the light emission of 400 nm or less. Such a fluorescent lamp has a relatively small decrease in visible light as compared with a fluorescent lamp for general illumination, and has a large amount of ultraviolet rays for irradiating the photocatalyst, so that the resolving power can be increased. Therefore, it is suitable as a lamp for activating the photocatalyst. However, a fluorescent lamp using a three-wavelength-type phosphor or a halophosphate phosphor that has been widely used for general illumination may be used. Further, it may be a sterilizing lamp, a black light, a chemical lamp or the like for the purpose of mainly using light emission of 400 nm or less. On the other hand, the high pressure discharge lamp may be, for example, a mercury lamp, a metal halide lamp, a high pressure sodium lamp, or the like. The glass bulb may be an arc tube that encloses the discharge medium, or an outer tube that further encloses the arc tube that encloses the light emitting portion. As described above, while the room is illuminated by the light emitted from the lamp, the photocatalyst film can be activated and the odorous gas can be decomposed and deodorized by the ultraviolet rays during the light emission. In particular, in the case of a lamp, since the photocatalyst film is disposed at a position where the ultraviolet intensity is high, almost the entire photocatalyst film can be activated well to perform strong deodorization.
[0054]
  Next, even when the functional body is a luminaire, since the luminaire is used at a position close to the lamp which is an ultraviolet ray generation source, the photocatalyst film can be favorably activated with a strong ultraviolet intensity. The part where the photocatalyst film is formed is preferably a part of the light control means in the lighting fixture. The light control means may be a plurality of one or a combination of any number of reflectors, gloves, shades, translucent covers, chandeliers, and louvers. Since the light control means controls the light emission of the lamp in order to obtain a desired light distribution and appearance, the light control means is also irradiated with the ultraviolet rays of the lamp, so a photocatalytic film is formed on this part. Therefore, the photocatalyst film can be activated as required, which is effective in decomposing and deodorizing the odorous gas. Moreover, since the odorous gas is decomposed by the photocatalytic film, the indoor deodorization is effectively performed. Further, the lighting apparatus is sized and structured so as to be accommodated in, for example, a refrigerator, an air conditioner, an air cleaning device, and the like, and disposed in these devices, deodorization can be performed in the devices.
[0055]
  Thus, even if dirt, bacteria, or odorous substances adhere to the site where the photocatalyst film is formed during use of the functional body, the photocatalyst film is decomposed and removed by being irradiated with ultraviolet rays.
[0056]
  Further, since the photocatalyst film, and if necessary, the underlayer can be formed by room temperature curing, the photocatalyst film can be formed on a functional body made of a combustible material such as curtain, wallpaper, and wood. Therefore, the material of the part forming the photocatalytic film of the functional body is not selected.
[0057]
  Furthermore, since the photocatalyst film can be formed on the functional body in use, if necessary, the application range of the photocatalyst film can be dramatically increased.
[0058]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below with reference to the drawings.
[0059]
    FIG. 1 is an enlarged schematic cross-sectional view of a main part of a photocatalyst film according to the first embodiment of the present invention.
[0060]
  In the figure, 1 is a substrate, 2 is an underlayer, and 3 is a photocatalytic film.
[0061]
    <About the substrate 1>
  The substrate 1 is made of soda lime glass.
[0062]
    <About the underlayer 2>
  The underlayer 2 is formed by binding silicon oxide fine particles 2a having an average particle diameter of 40 nm with a room temperature curable binder 2b mainly composed of a Si compound. The binder 2b is made of SiO.₂The film is 15% by weight in terms of conversion, is transparent and porous, and has a surface formed on an uneven surface having an average depth of about 20 nm.
[0063]
    <About the photocatalytic film 3>
  The photocatalyst film 3 is formed by binding an ultrafine particle 3a of titanium oxide mainly composed of anatase having an average particle diameter of about 7 nm on the underlayer 2 with a room temperature curable binder 3b mainly composed of a Si compound. ing. The binder 3b is made of SiO.₂It is 10% by weight in terms of conversion. The photocatalytic film 3 enters an uneven surface formed on the surface of the underlayer 2 and is in close contact with the underlayer 2.
[0064]
    FIG. 2 is an enlarged cross-sectional view of a conceptual main part showing a second embodiment of the photocatalyst body of the present invention.
[0065]
  In the figure, the same parts as those in FIG.
[0066]
  This embodiment is different in that the organic dye 4 is dispersed in the photocatalytic film 3.
[0067]
    FIG. 3 is an enlarged cross-sectional view of a conceptual main part showing a third embodiment of the photocatalyst body of the present invention.
[0068]
  In the figure, the same parts as those in FIG.
[0069]
  This embodiment is different in that there are two types of average particle diameters of the metal oxide fine particles in the underlayer 2.
[0070]
  That is, the underlayer 2 is made of Al with an average particle diameter of 15 nm as metal oxide fine particles.₂O₃Fine particles 2a1 and Al having an average particle diameter of 55 nm₂O₃In a state where the fine particles 2a2 are mixed, it is formed by binding with a room temperature curable binding material 2b. Al with any average particle size₂O₃The fine particles 2a1 and 2a2 also have a particle size distribution with a half width of about ± 5 nm.
[0071]
    FIG. 4 is a front view, partly cut away, of the main part of the fluorescent lamp as the first embodiment of the functional body of the present invention.
[0072]
  In the figure, 11 is a glass bulb, 12 is a photocatalytic film, 13 is a phosphor layer, 14 is a filament electrode, and 15 is a base.
[0073]
  The glass bulb 11 functions as a base with respect to the photocatalyst film 12 and houses therein a functional part as a fluorescent lamp in an airtight manner. That is, several hundred Pa of rare gas mainly composed of mercury and argon as a discharge medium is sealed inside the glass bulb 11, the phosphor layer 13 is supported on the inner surface, and a pair of filament electrodes 14 are sealed at both ends. Yes.
[0074]
  The base 15 is composed of an aluminum cap-shaped base body 15 a and a pair of base pins 15 b that are insulated and attached to the base body 15 a, and are bonded to both ends of the glass bulb 11. Both ends of the filament electrode 14 are connected to the cap pin 15b.
[0075]
  Then, when the fluorescent lamp which is a functional body of the present embodiment is used for illumination, the organic fouling substance adhering to the surface of the fluorescent lamp is decomposed by the photocatalytic action of the photocatalyst film 12, and the odorous substance in the air in contact Is decomposed and the surrounding deodorization is performed.
[0076]
    FIG. 5 is a conceptual cross-sectional view showing a tunnel lighting device as a second embodiment of the functional body of the present invention.
[0077]
  In the figure, 21 is a luminaire main body, 22 is a front frame, 23 is a translucent glass cover, 24 is a lamp socket, 25 is a high-pressure discharge lamp, and 26 is a reflector.
[0078]
  The luminaire main body 21 is formed by forming a stainless steel plate into a box shape having an opening on the front surface, and includes a mounting bracket (not shown) on the back surface.
[0079]
  The front frame 22 is formed of a stainless steel plate, and includes a light projection opening at the center, a hinge on one side, and a latch (none of which are shown) on the other side. And it is comprised by the hinge so that it can be freely opened and closed by the one side part of the front surface side of the lighting fixture main body 21, and it is comprised so that it may fix to a closed position with a latch.
[0080]
  The translucent glass cover 23 is waterproofly attached to the front frame 22 via a silicone rubber packing (not shown). The translucent glass cover 23 transmits visible light and has a relatively high transmittance characteristic in at least a part of the ultraviolet region having a wavelength of 400 nm or less. Further, the photocatalytic film shown in FIG. 1 is formed on the front surface of the translucent glass cover 23.
[0081]
  The lamp socket 24 is disposed in the lighting fixture body 21.
[0082]
  The high-pressure discharge lamp 25 emits ultraviolet rays having an intensity of 0.05 W or more per 1000 lm of visible light within a wavelength range of 340 to 400 nm.
[0083]
  The reflector 26 is disposed in the luminaire main body 21, and is configured and arranged so that the light emitted from the high-pressure discharge lamp 25 is reflected by the reflector 26 and exhibits a required light distribution characteristic. Yes.
[0084]
  A ballast, a terminal block, and the like are disposed on the back side of the reflector 26 of the lighting fixture body 21.
[0085]
  Thus, the functional body of the present embodiment is installed in the tunnel via the mounting bracket and used for illuminating the inside of the tunnel.
[0086]
  Further, since ultraviolet rays mainly in the wavelength range of 340 to 400 nm radiated from the high-pressure discharge lamp 25 simultaneously with the illumination pass through the translucent glass cover 23 together with visible light and enter the photocatalyst film, the photocatalyst film is made of ultraviolet rays. The self-cleaning is performed by decomposing organic matter such as soot and smoke activated by the
[0087]
【The invention's effect】
    Claim1According to the invention, the film strength of the underlayer is improved by being bound by the room temperature curable binder in a state where the metal oxide fine particles having different average particle diameters of two or more types are mixed. As a result, the adhesion strength of the photocatalytic film is improved.In addition, it is easy to manufacture by curing at room temperature, can form a photocatalytic film on various substrates, and has high photocatalytic propertiesA photocatalyst can be provided.
[0088]
    Claim2According to the invention ofDisperse metal oxide fine particles having different average particle diameters in two or more kinds in a liquid containing a binder dispersion forming material and a solution.The photocatalyst having the effect of claim 1 can be easily obtained by providing the first coating solution adjusting step, the undercoat layer arranging step, the second coating solution adjusting step, and the photocatalyst film arranging step. Then, it can be manufactured even at a site where the substrate is used as a functional body.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view of a conceptual part showing an enlarged cross section of a photocatalyst film in a first embodiment of a photocatalyst body of the present invention.
FIG. 2 is an enlarged cross-sectional view of a conceptual part showing an enlarged cross section of a photocatalyst film in a second embodiment of the photocatalyst body of the present invention.
FIG. 3 is an enlarged cross-sectional view of a conceptual part showing an enlarged cross section of a photocatalyst film in a third embodiment of the photocatalyst body of the present invention.
FIG. 4 is a cross-sectional front view of an essential part of a fluorescent lamp as a first embodiment of a functional body of the present invention.
FIG. 5 is a conceptual cross-sectional view showing a tunnel lighting apparatus as a second embodiment of the functional body of the present invention.
[Explanation of symbols]
      1 ... Substrate
      2 ... Underlayer
      2a ... Silicon oxide fine particles
      2b ... normal temperature curable binder
      3 ... Photocatalytic film
      3a ... Ultrafine titanium oxide particles
      3b ... normal temperature curable binder

Claims (2)

A substrate;
It consists of an oxide of one or more kinds of metals selected from the group of Al, Zr, Si, Ti, Zn, Mg, Y, In, Sn, Ta and Sb, and has an average particle diameter in the range of 10 to 100 nm. An underlayer disposed on the surface of the substrate, which is bound by a binder mainly composed of a Si compound in a state where metal oxide fine particles having different average particle diameters of two or more types are mixed;
The photocatalytic metal oxide ultrafine particles mainly composed of titanium oxide ultrafine particles whose average particle size is smaller than the average particle size of the metal oxide ultrafine particles of the underlayer are bound by a room temperature curable binder, A photocatalytic film disposed on the substrate;
The photocatalyst body characterized by comprising. It consists of an oxide of one or more kinds of metals selected from the group of Al, Zr, Si, Ti, Zn, Mg, Y, In, Sn, Ta and Sb, and has an average particle diameter in the range of 10 to 100 nm. And a first coating liquid obtained by dispersing metal oxide fine particles having different average particle diameters of two or more types in a liquid containing a binder-forming material that forms a binder mainly composed of an Si compound and a solvent. A first coating liquid adjusting step of adjusting
An undercoat layer disposing step of applying a first coating liquid to the surface of the substrate and drying to dispose an undercoat layer having at least a porous surface;
A photocatalytic metal oxide ultrafine particle mainly composed of titanium oxide ultrafine particles whose average particle size is smaller than the average particle size of the metal oxide fine particles of the underlayer, a binder forming material for forming a room temperature curable binder, and a solvent. A second coating liquid adjusting step of adjusting a second coating liquid dispersed in the liquid containing;
A photocatalyst film disposing step of applying a second coating liquid on the base layer of the substrate and drying to dispose the photocatalyst film;
The manufacturing method of the photocatalyst body characterized by comprising.

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