JP6258163B2 - Ultraviolet-transmissive window material having photocatalytic function and ultraviolet irradiation apparatus having the window material - Google Patents

Description

  The present invention relates to an ultraviolet transmissive window material having a photocatalytic function and an ultraviolet irradiation apparatus having the window material.

  Unlike sterilization with chemicals, ultraviolet sterilization is suitable as a method for sterilization of breeding water for aquatic organisms such as farmed fish and ornamental fish because it has no residue and is highly safe. And when fish is cultivated using breeding water that has been sterilized by ultraviolet rays, it is possible to effectively prevent the death caused by bacterial infection of the fish. Can be significantly reduced, and it becomes possible to produce cultured fish with high added value in terms of safety and security.

  As an apparatus for performing such ultraviolet sterilization of breeding water, apparatuses described in Patent Documents 1 to 3 and 6 using a mercury lamp as an ultraviolet light source are known.

In addition, in Patent Document 6, a large number of quartz balls coated with TiO _2, which is a photocatalytic substance, are disposed in the flow path of the fluid to be sterilized in anticipation of a sterilizing effect by active oxygen or ozone. Etc. are described. The composition for photocatalyst coating for applying the photocatalyst substance to the surface of the substrate is a mixture of a binder having a photocatalyst substance supported on an inorganic transparent porous body as described in Patent Document 7. Something is also known.

  By the way, although an ultraviolet light emitting diode (hereinafter also referred to as UV-LED) has a drawback that it emits less ultraviolet light than a mercury lamp, it has a long life and low power consumption. It is often preferable to use a UV-LED as the light source because of the excellent feature that mercury contamination does not occur. And as what uses such UV-LED, the apparatus as described in patent document 4 and patent document 5 is known.

  In the sterilization apparatus disclosed in Patent Document 4, the main light emission is used as a light source in order to avoid the problem that the sterilization effect decreases due to the light recovery phenomenon of bacteria when the sterilized water is exposed to sunlight. A UV-LED emitting UVA having a peak of 320 to 400 nm is preferably used in combination with an ultraviolet lamp emitting UVC having a main emission peak of 254 nm. However, it is known that ultraviolet rays having a wavelength near 260 nm (so-called sterilization line) are higher, and when sterilization is performed in an environment where the influence of sunlight is small or substantially negligible, It is advantageous to irradiate ultraviolet rays having a wavelength of preferably 200 to 350 nm, more preferably 200 to 300 nm, most preferably 200 to 280 nm.

Japanese Patent Laid-Open No. 08-243554 JP 08-252575 A JP 2014-131787 A International Publication No. 2010/058607 Pamphlet JP2012-115715A JP 09-234237 A Japanese Patent Laid-Open No. 10-156988

  As described in Patent Documents 1 to 3, when water containing microorganisms and suspended solids is sterilized with ultraviolet rays, contaminants such as organic substances in the liquid are present on the outer surface of the light transmission tube containing the ultraviolet lamp. In order to prevent the ultraviolet irradiation efficiency from being reduced due to adhesion, it was necessary to appropriately perform automatic cleaning. Such automatic cleaning is performed at relatively long intervals, such as when the contamination exceeds a certain level while monitoring the contamination status, or only when the device starts operating. Was common. In addition, the automatic cleaning shown in Patent Documents 1 and 2 requires a relatively large energy cost, such as sliding a scraper or brush using a motor, or increasing turbulence by air injection. It was performed by a device having a complicated mechanism. Moreover, although the method described in Patent Document 3 can be cleaned at a low energy cost by a simple mechanism, it can be performed only when the shape of the light source or the sterilization chamber is specified, and the cleaning frequency can be reduced. It was difficult to control.

  Thus, in the ultraviolet sterilizer using a mercury lamp as a light source, it was possible to sterilize stably for a long period of time by using the automatic cleaning device as described above. And in the apparatus using UV-LED as a light source as shown in patent document 5, and an ultraviolet permeable window material, an automatic cleaning device is provided and a window material (the window material in the present invention is a light source, a light source, A material that constitutes a light-transmitting partition wall that is interposed between and spaced from an irradiated object irradiated with light emitted from the light source and through which the light emitted from the light source can be irradiated to the irradiated object For example, the protective cover 19 in Patent Document 5 and the translucent plate 7, translucent transfer tube 23, and translucent container 33 in Patent Document 4 also correspond to window materials.) It was supposed that it could be used without any problems.

  However, in the circulation sterilization of fish breeding water using an apparatus as shown in FIG. 12 of Patent Document 4 using only UV-LED as a light source under conditions where there is no sunlight irradiation, the sterilization effect is short. It became clear that it might decrease rapidly. And, when trying to maintain the sterilization efficiency by frequently performing cleaning using the automatic cleaning as shown in Patent Document 1, 2, or 5, not only a great energy cost is required, but also the automatic cleaning device is frequently used. Maintenance work needs to be done.

  In order to solve the above problems, the present inventors have intensively studied to find out the cause. As a result, since the emission intensity of the UV-LED is significantly lower than that of the mercury lamp, especially when it is difficult for ultraviolet rays to reach the irradiated object having a wide flow path and away from the light source, the fishes are compared with the case of using the mercury lamp. Dirty objects (especially microbial contaminants) derived from microorganisms and suspended solids contained in the breeding water easily adhere to the inner wall of the transfer pipe, and even at a slight level that does not cause a problem when using a mercury lamp. Even when an object adheres, it has been clarified that the cause is that the intensity of ultraviolet rays reaching the breeding water, which is a sterilized body, is remarkably reduced due to the ultraviolet absorption effect of the dirty object.

  From such a cause, the above problem can be solved if the emission intensity of the UV-LED can be remarkably increased. However, in order to increase the emission intensity, it is necessary to use a very large number of UV-LEDs, which is not only economically disadvantageous, but also increases the size of the apparatus. If the luminous efficiency of individual UV-LEDs is increased, the number of UV-LEDs to be used can be reduced to a relatively low level. However, for this purpose, it is necessary to increase the operating voltage, leading to a decrease in the life of the UV-LEDs. I will.

Under such circumstances, the present inventors have conceived of providing a self-cleaning function using a photocatalyst. However, TiO _2, which is the most widely used photocatalytic substance, may be applied to a substrate that requires visible light transmission, as can be seen from the fact that it is a typical ultraviolet absorber. However, as far as the present inventors know, there are no examples of application to a window material that requires ultraviolet transparency. And in the article | item which has the self-cleaning property using a photocatalyst, the excitation light for exciting a photocatalyst is irradiated from the exposed surface side of a photocatalyst coating layer almost without exception.

  Therefore, the photocatalyst has a high ultraviolet shielding property (or ultraviolet absorbing property) and is not limited to the common sense that it cannot be applied to a window material that requires ultraviolet light transmission, and without impairing the ultraviolet light transmittance of the window material. The method of giving the self-cleaning function used was studied earnestly. As a result, it is not always necessary to apply a photocatalyst coating to the entire surface in order to provide a self-cleaning function. If the photocatalyst coat layer is dispersed and formed so that an uncoated portion remains, the ultraviolet transmittance is greatly reduced. The inventors have conceived that a photocatalytic function can be imparted without causing the present invention to be completed.

That is, the first aspect of the present invention is a window material that transmits ultraviolet rays irradiated from the inner space toward the outer space, and is provided on the window material body and the outer surface of the window material body. A photocatalyst coating layer comprising a formed photocatalytic substance,
The window material body is made of a material having transparency to ultraviolet light having a wavelength of 220 to 280 nm and excitation light of the photocatalytic substance,
The photocatalyst coat layer is composed of a plurality of independent photocatalyst coat layers formed so as to be substantially uniformly dispersed in an effective surface that is an outer surface of a portion through which ultraviolet rays of the window material can transmit, or A punched net-like photocatalytic coat layer, wherein the punched portion is formed so as to be substantially uniformly dispersed in the effective surface,
Wherein the ratio of the total area of the photocatalytic coating layer to the total area of the effective surface (%) defined in the coverage Ri 2-95% der,
The portion of the effective surface that is not covered with the photocatalyst coat layer is an effective portion that does not have a photocatalyst coat layer and is capable of transmitting ultraviolet rays.

  The window material according to the first aspect of the present invention has a feature that a self-cleaning effect can be exhibited by irradiating the window material with excitation light of the photocatalytic substance from the inside of the window material. In the window material of the present invention, from the viewpoint that it can be easily produced, the photocatalyst coat layer is composed of an inorganic binder whose cured body is transparent to ultraviolet rays and excitation light of the photocatalyst material, and a photocatalyst material or a precursor thereof. And a cured body of a curable composition comprising the body. And the content of the photocatalyst substance contained in the photocatalyst coat layer made of such a cured product is preferably 0.5 to 20% by mass, particularly preferably 1 to 15% by mass, and the photocatalyst coat layer has a thickness of 0. The thickness is preferably 3 to 50 μm, particularly preferably 0.5 to 10 μm. Furthermore, it is most preferable that the content of the photocatalytic substance contained in the photocatalyst coat layer is 0.5 to 15% by mass and the thickness of the photocatalyst coat layer is 0.5 to 10 μm. By setting the content of the photocatalyst substance and / or the thickness of the photocatalyst coating layer in such a range, high ultraviolet transmittance can be obtained even if the coverage is increased, and the entire surface of the effective surface of the window material is obtained. A high self-cleaning function can be imparted uniformly.

  In the window material of the present invention, a concave recess having an opening shape corresponding to the shape of the photocatalyst coat layer is formed on the surface of the outer surface of the window material body, and the photocatalyst coat layer is formed into the concave recess. It may be formed in close contact with the inside. By doing in this way, the outer surface of the window material can be made flat or a smooth curved surface to make it difficult for dirt to accumulate. And it becomes possible to prevent exfoliation of a photocatalyst coat layer by making the diameter of the above-mentioned concave hollow expanded in the depth direction.

  The second aspect of the present invention includes a light source that emits ultraviolet rays and a casing having a window portion, and the light source is accommodated in the casing, and the window portion has the photocatalytic function of the present invention. An ultraviolet irradiation device comprising an ultraviolet transmissive window material.

  The ultraviolet irradiation apparatus according to the second aspect of the present invention can exert a self-cleaning effect by irradiating the window material with excitation light of the photocatalytic substance from the inside of the apparatus. In the ultraviolet irradiation device of the present invention, when the ultraviolet light emitted from the light source does not include the excitation light of the photocatalytic substance, or the ultraviolet light emitted from the light source includes the excitation light of the photocatalytic substance, it is sufficient. Even if the intensity is not sufficient, a light source that emits ultraviolet light and excitation light of the photocatalytic substance is used as a light source housed in the casing because it is not necessary to separately install a light source of the excitation light outside. Or another light source that emits excitation light of the photocatalytic substance together with the light source (preferably one having a light emission intensity stronger than the light source) is preferably housed in the casing.

  The window material of the present invention has a feature that it has ultraviolet transmittance despite having a photocatalyst coating layer generally known to have ultraviolet shielding properties or ultraviolet absorption properties on the surface. Therefore, when an ultraviolet light source such as a UV-LED or an ultraviolet lamp is housed in the casing and used as a window material for an ultraviolet irradiation device that emits ultraviolet light from a window portion provided in the casing, By irradiating the window material with excitation light of the photocatalyst particles from the inside, a self-cleaning effect can be exhibited.

  Therefore, when the window material of the present invention is used as a window material in an apparatus for sterilizing water containing microorganisms and suspended matters, the frequency of decomposition cleaning and automatic cleaning can be greatly reduced. In addition, since it is not necessary to install a light source for excitation light of the photocatalyst material outside, the apparatus can be made compact.

This figure is a schematic view of a typical window material of the present invention and an ultraviolet irradiation apparatus using the same. This figure is a schematic view of another typical window material of the present invention and an ultraviolet irradiation apparatus using the same. This figure is a schematic view of still another typical window material of the present invention and an ultraviolet irradiation apparatus using the same. This figure is a schematic diagram of another typical window material of the present invention.

  The window material of the present invention is a window material that transmits ultraviolet rays irradiated from the inner space to the outer space, and has a window material body and a photocatalyst coating layer containing a photocatalytic substance. The window material body is made of a material that is transparent to ultraviolet light and excitation light of the photocatalytic substance, and the photocatalyst coating layer is formed on the outer surface of the portion of the window material through which ultraviolet light can pass. A plurality of independent photocatalyst coat layers formed so as to be substantially uniformly dispersed in an effective surface, or a punched net-like photocatalyst coat layer, the punched portion being substantially in the effective surface The photocatalyst coat layer formed so as to be uniformly dispersed in the surface area, and the coverage defined by the ratio (%) of the total area of the photocatalyst coat layer to the total area of the effective surface is 2 to 95%. Features.

  As described above, in the present invention, the window material is interposed between the light source and the irradiated object irradiated with the light emitted from the light source and separates both, and the light emitted from the light source is irradiated therethrough. It means a material constituting a light-transmitting partition wall that can be irradiated to the body. Therefore, 1) a light source is accommodated in a container having an opening, the opening is closed and sealed with a light-transmitting plate, and the light source is disposed on the outside of the light-transmitting plate. 2) the light-transmitting plate-like body in the light irradiation device of the type that emits light; 2) a light source is housed inside the light-transmitting tubular body, both ends are closed with lids, and the light-transmitting tubular body is sealed; The translucent tubular body in a light irradiating apparatus of the type that irradiates light toward the irradiated body disposed outside the 3), and 3) the irradiated body is disposed inside the translucent tubular body, and the translucent The light-transmitting tubular body in a light irradiation device of a type that irradiates light toward the irradiated body by arranging a light source along the outer periphery of the tubular body, and further 4) a window material in a so-called LED package or LED module, The material constituting the lens, the translucent cover, etc. is also included in the window material.

  The window material of this invention is a window material which permeate | transmits the ultraviolet-ray irradiated from the space inside the outer space. Here, the ultraviolet rays mean light in the wavelength region of 200 nm to 400 nm, but it is not necessary to transmit all ultraviolet rays in the wavelength region, and the type of light source when used as a window material of an ultraviolet irradiation device, the purpose of ultraviolet irradiation It is only necessary to have transparency to specific ultraviolet rays. In the window material of the present invention, the transmittance for ultraviolet light having a wavelength corresponding to the main peak when ultraviolet light having a single or plural peaks in the wavelength region of 200 nm to 400 nm is transmitted is 30.0% or more. It is preferably 5% or less, more preferably 50% or more and 98% or less, and particularly preferably 60% or more and 97% or less.

The photocatalyst coat layer of the window material of the present invention means a film containing a photocatalyst material as described later, and is a thin film composed of only a photocatalyst material such as a vapor-deposited film of a photocatalyst material (general film thickness is 100 nm to 10 μm). And a preferable film thickness is 150 nm to 5 μm. From the viewpoint of ease of formation, the photocatalyst coating layer has a curable composition comprising an inorganic binder whose cured body is transparent to ultraviolet rays and excitation light of the photocatalytic substance, and a photocatalytic substance or a precursor thereof. It is preferable to consist of a cured product of the product. Here, as the curable composition, among the photocatalyst coating agent comprising a photocatalyst substance and a binder that are available as a normal photocatalyst coating agent, the cured product is used as an ultraviolet ray and excitation light of the photocatalyst substance. On the other hand, an inorganic material having permeability can be used without any particular limitation. As the photocatalytic substance, a substance known to exhibit a photocatalytic action, for example, TiO ₂ , SrTiO ₂ , ZnO, CdS, SnO ₂ , WO _{3 and the} like can be used without particular limitation. From the viewpoint of high photocatalytic effect, it is preferable to use fine particles of TiO ₂ or TiO ₂ -based photocatalytic substance as the catalytic substance. The particle diameter of the fine particles of the photocatalyst material may be in the range of 5 nm to 1 μm for the primary particles determined by image analysis of the transmission electron microscope image. From the viewpoint of the high photocatalytic function, the particles of the primary particles The diameter is preferably 5 to 50 nm.

  Further, as the inorganic binder whose cured body is transparent to ultraviolet rays and excitation light of the photocatalytic substance, a silicate binder, an inorganic colloid binder, a metal alkoxide binder, and the like can be used. Furthermore, the curable composition may contain water and / or an organic solvent for the purpose of adjusting the viscosity. The transparency of the cured inorganic binder to ultraviolet light and the excitation light of the photocatalytic substance is often lower than that of the window material body.

  The concentration of the photocatalyst substance in the curable composition depends on the thickness of the photocatalyst coat layer from the balance between the strength of the photocatalyst function and the ultraviolet light transmittance when cured to form a photocatalyst coat layer. It is preferable to set it as 0.5-20 mass% by mass reference | standard, especially 1-15 mass%. The thickness of the photocatalyst coat layer is generally in the range of 0.3 to 50 μm. In order to easily expose the photocatalyst substance to enhance the photocatalyst function and further increase the ultraviolet transmittance in the photocatalyst coat layer as much as possible. It is preferable to set it as 0.5-10 micrometers. When no component other than the solvent is added to the curable composition, the remainder excluding the mass of the photocatalytic substance on the basis of the mass of the cured product is substantially the mass of the binder cured product.

The window main body used in the window material of the present invention constitutes the main part of the window material, and needs to be made of a material that is transparent to ultraviolet light and excitation light of the photocatalytic substance. Here, the excitation light of the photocatalytic substance is light that is excited when the photocatalytic substance (which is a semiconductor substance) absorbs the light and functions as a photocatalyst, and its wavelength is unique to each photocatalytic substance. . For example, the excitation light of TiO ₂ is light having a wavelength of 380 nm or less.

  As materials constituting the window material body, inorganic materials such as sapphire, natural or synthetic quartz, calcium fluoride, magnesium fluoride, and glass, fluorine-based resins such as PFA, FEP, ETFE, and PCTFE, polyethylene, polypropylene, PVC, An organic material such as polycarbonate and a composite material thereof (for example, an exposed surface of calcium fluoride or magnesium fluoride coated with a fluorine resin) can be suitably used. Among these window materials, it is preferable to use sapphire, natural or synthetic quartz, or an exposed surface of calcium fluoride or magnesium fluoride coated with a fluorine-based resin from the viewpoint of water resistance. From the viewpoint, the exposed surface of sapphire, natural or synthetic quartz, calcium fluoride, or magnesium fluoride (the exposed surface here refers to the portion directly exposed to the outside when the window material is used, that is, the outside surface of the window material body) The surface of the portion not covered with the photocatalyst coating layer is particularly preferably used as a coating of a fluororesin. Note that the thickness of the window material body is preferably thin from the viewpoint of ultraviolet transparency, and may be appropriately determined from the balance between ultraviolet transparency, strength, and ease of handling. The general thickness is usually in the range of 20 μm to 10 mm, but is preferably in the range of 50 μm to 7 mm, particularly 100 μm to 5 mm.

  In the window material according to the present invention, the photocatalyst coat layer includes a plurality of independent photocatalyst layers formed so as to be substantially uniformly dispersed in an effective surface which is an outer surface of a portion of the window material through which ultraviolet rays can pass. A photocatalyst coat layer having a punched net shape, wherein the punched portion is formed so as to be substantially uniformly dispersed in the effective surface. The coverage defined by the ratio (%) of the total area of the photocatalyst coat layer to the area needs to be 2 to 95%. When the coverage is less than 2%, a sufficient photocatalytic function or self-cleaning function cannot be obtained, and when the coverage is more than 95%, the content and film thickness of the photocatalyst contained in the photocatalyst coating layer are possible. Even if it is controlled within the range, a significant decrease in ultraviolet transmittance is inevitable. The higher the coverage, the higher the self-cleaning function and the lower the ultraviolet transmittance, so the coverage may be controlled according to the use environment and purpose. For example, when used in a highly contaminated environment, the coverage is increased, for example, 70% or more and 95% or less or 80% or more and 95%. The rate may be reduced to 2% or more and less than 30% or 2% or more and less than 20%. In addition, it is known that when the coverage is in the range of 0 to 10%, the surface is rapidly hydrophilized as the coverage increases, and dirt attached to the surface can be easily removed by a water film (Reference Patent Document 1: (Refer to Japanese Patent No. 3773087). Therefore, when used under the condition that the outer surface of the window material is always in contact with the water flow, the coverage is considerably low (for example, 2% to 10%, preferably 2% to 7%). Even if it exists, it is thought that sufficient self-cleaning effect can be acquired.

  The method for depositing the plurality of photocatalyst coat layers so as to be substantially uniformly dispersed on the outer surface of the window material main body is not particularly limited. For example, as described in Reference Document 1 above The average dispersion distance interval is within 1 mm so that the island-shaped photocatalyst coat layer having a diameter or maximum diameter of 5 mm or less, preferably 0.1 μm to 1 mm, is uniformly dispersed on the outer surface of the window material body, preferably What is necessary is just to adhere to a discontinuous film form so that it may be set to 0.1 micrometer-1 mm. In addition, when using it on the conditions where the outer side surface of a window material always contacts flowing water, you may disperse | distribute coarsely and an average dispersion distance is good within 10 mm, Preferably it is good within 5 mm.

  As a method for depositing a plurality of photocatalyst coat layers in a discontinuous film shape, for example, 1) A protective film having a predetermined pattern is formed in advance on the outer surface of the window material body using a photoresist or the like, and then applied to the entire surface. A method of forming a photocatalyst coat layer, and then removing the unnecessary photocatalyst coat layer by a lift-off method or the like. 2) A concave recess of a predetermined shape is formed in a predetermined pattern on the outer surface of the window material body in advance, and the interior of the recess 3) A method of selectively forming a photocatalyst coat layer and polishing the surface as necessary. 3) After forming the photocatalyst coat layer over the entire surface where the concave recesses are formed in a predetermined pattern, the surface is polished and the exterior of the recesses. For example, a method of removing the photocatalyst coat layer formed on the substrate can be employed. According to the above method 2) or 3), the outer surface of the window material can be made into a smooth flat surface or a smooth curved surface by surface polishing, and there is no step or groove on the surface where dirt easily accumulates. A removal effect can be obtained.

  In addition, as a method for forming the photocatalyst coating layer, a method such as a vapor deposition method or a sputtering method can be employed when a layer made of only a photocatalytic substance is formed. In the case of using a curable composition containing photocatalyst fine particles and an inorganic binder, the composition is applied using a coating method such as a dipping method, a spin coating method, or a spray method, and then dried and subjected to a heat treatment or the like. What is necessary is just to harden.

  In addition, when forming a photocatalyst coat layer that is a punched net-like photocatalyst coat layer so that the punched portions are substantially uniformly dispersed on the effective surface, it corresponds to the shape of the punched net. A concave depression is formed, and a photocatalyst coating layer may be formed in the concave groove similarly. The punching net is also called punching metal, and has a metal plate with a large number of holes of a predetermined shape. The punching net-like photocatalytic coating layer is, for example, a photocatalytic coating on the sea part of the sea island structure. A layer formed (the island portion corresponds to a hole and the photocatalyst coat layer does not exist) is exemplified.

  Hereinafter, the window material and ultraviolet irradiation device of the present invention will be described in more detail with reference to the drawings.

FIG. 1 shows a UV-LED 8 that emits UVC (ultraviolet light having a wavelength of 200 to 280 nm) having a high bactericidal effect in a box-shaped casing 6 having an opening in the upper portion and a UVA (wavelength 320 to 300 nm) that has a high TiO ₂ photocatalyst. The ultraviolet irradiation device 10 of the present invention is shown in which a UV-LED 9 (400 nm ultraviolet light) is housed and the window portion 7 is configured by closing the opening with the window material 1 of the present invention. The window material 1 has a window material body 2 made of sapphire or quartz and a plurality of photocatalyst coating layers 3. The photocatalyst coat layer 3 is formed inside a concave recess 5 formed in a “portion (effective portion) 4 through which ultraviolet rays can pass” surrounded by a dotted line of the window material body 2. Since the diameter of the recess 5 is increased in the depth direction toward the inside, the photocatalyst coat layer 3 is difficult to peel off. Further, when the photocatalyst coat layer 3 is formed on the outer surface of the window material body having a flat outer surface, the photocatalyst coat layer 3 becomes a convex portion, and a step is generated on the surface of the window material, so that dirt is difficult to remove and a dirt reservoir is formed. Although it is easy to form, in the window material 1, the exposed surface of the photocatalyst coating layer 3 forms a flat surface at the same height as the exposed surface of the window material body, so that a high dirt removal effect can be obtained. The portion of the window material 1 where light passes through each catalyst coat layer 3 has a circular shape with a diameter D (as viewed from directly above the window material or the bottom surface of the concave recess), and this is a constant interval (the closest catalyst) A dispersion distance interval (L) that is a distance from the coat layer 3 is arranged in the vertical and horizontal directions. In the window material 1, D is twice as long as L, so the coverage is about 33%. In the window material 1, all the catalyst coat layers 3 have the same shape and the same area, but the shape and size of the catalyst coat layer 3 can be freely changed.

In the window material 1, the catalyst coat layer 3 is formed using a curable composition (photocatalyst coating agent) containing TiO ₂ fine particles as a photocatalytic substance and further containing an inorganic binder such as silica sol. In the ultraviolet irradiation device 10, a UV-LED 9 that emits UVA is housed in the casing 6 in order to increase the excitation efficiency of TiO ₂ in addition to the UV-LED 8 that emits UVC having a strong bactericidal action. In general, it is difficult to increase the light emission intensity in the UV-LED 8 that emits UVC, whereas it is relatively easy to increase the intensity in the UV-LED 9 that emits UVA. The photocatalytic function can be further enhanced as compared with the case of using only. Although FIG. 1 shows a mode in which only a UV-LED is used as a light source, it is of course possible to use a combination of a low-pressure mercury lamp that emits UVC or an excimer UV lamp and a UV-LED 9 that emits UVA. is there.

  As a material constituting the casing 6 in the ultraviolet irradiation device 10, metals, ceramics, resins, composite materials of these, and the like can be used. The method for housing the light source in the casing 6 is not particularly limited, and each UV-LED may be housed in the state of an element, or may be housed in a package or a module. In FIG. 1, the details of the mounting state of the UV-LED and the power source, wiring, circuit, etc. for driving the UV-LED are omitted.

  FIG. 2 shows another window material 1a of the present invention and an ultraviolet irradiation apparatus 10a using the same. The window material 1a and the ultraviolet irradiation device 10a are different from each other in the dispersion state of the catalyst coating layer 3a and the arrangement state of the UV-LED 8a that emits UVC and the UV-LED 9a that emits UVA, respectively. There is no particular difference from the ultraviolet irradiation device 10. That is, in the window material 1a, the number of catalyst coat layers 3a is reduced, the dispersion distance is quadrupled, and the coverage is about 9%. In the casing, the UV-LED 9a for photocatalyst excitation is disposed immediately below the catalyst coat layer 3a, and the UV-LED 8a having a strong bactericidal action is disposed immediately below the portion not covered with the catalyst coat layer 3a. Yes. By adopting such an arrangement, for example, when the ultraviolet irradiation device 10a is used as a light source for the ultraviolet sterilization device, UVC emitted from the UV-LED 8a can be effectively utilized, and the photocatalyst is sufficiently excited by the UV-LED 9a. Therefore, efficient sterilization and self-cleaning are possible. In addition, not only the ultraviolet irradiation device 10a but also the other embodiments of the ultraviolet irradiation device of the present invention, a light source for photocatalyst excitation is disposed immediately below the catalyst coat layer 3a and the object to be irradiated for the same effect. It is preferable to dispose the ultraviolet light source to be irradiated directly below the portion not covered with the catalyst coat layer 3a.

  FIG. 3 shows the ultraviolet irradiation device 10b of the present invention using the ultraviolet lamp 11 as a light source and the window material 1b of the present invention used for the same. In the window material 1b, the concave recess 5b is the same as the window material 1 shown in FIG. 1 except that the area of the opening is the area of the bottom. Moreover, in the ultraviolet irradiation device 10b, one or a plurality of ultraviolet lamps 11 arranged in parallel is housed as a light source. As the ultraviolet lamp, a high-pressure mercury lamp having a broad emission spectrum (which emits UVC and UVA simultaneously) is used.

  FIG. 4 shows a window material 1c in which the surface of the portion of the outer surface of the window material body 2c that is not covered with the photocatalyst coat layer is coated with the fluorine resin 12. The window material 1c is characterized in that dirt is more difficult to adhere because the exposed surface not covered with the photocatalyst coat layer 3c is covered with a thin fluororesin. In the window member 1c, the concave groove formed on the front surface of the window member body 2c is not expanded in the depth direction, but a part of the upper side (outer side) of the groove side surface is coated with the fluororesin 12. In this case, the photocatalyst coat layer 3c can be prevented from peeling off due to the anchor effect.

DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c ... Window material of this invention 2, 2a, 2b, 2c ... Window material main body 3, 3a, 3b, 3c ... Photocatalyst coat layer 4, 4a, 4b ... Ultraviolet 5, 5a, 5b ... concave groove 6, 6a, 6b ... casing 7, 7a, 7b ... window 8, 8a ... UV-LED emitting UVC
9, 9a ... UV-LED emitting UVA
DESCRIPTION OF SYMBOLS 10, 10a, 10b ... Ultraviolet irradiation apparatus of this invention 11 ... Ultraviolet lamp (high pressure mercury lamp)
12 ... Fluororesin

Claims (8)

A window material that transmits ultraviolet light emitted from the inner space toward the outer space, and includes a window material body and a photocatalytic substance formed on an outer surface of the window material body. A photocatalyst coating layer,
The window material body is made of a material having transparency to ultraviolet light having a wavelength of 220 to 280 nm and excitation light of the photocatalytic substance,
The photocatalyst coat layer is composed of a plurality of independent photocatalyst coat layers formed so as to be substantially uniformly dispersed in an effective surface that is an outer surface of a portion through which ultraviolet rays of the window material can transmit, or A punched net-like photocatalytic coat layer, wherein the punched portion is formed so as to be substantially uniformly dispersed in the effective surface,
Wherein the ratio of the total area of the photocatalytic coating layer to the total area of the effective surface (%) defined in the coverage Ri 2-95% der,
The ultraviolet transmissive window material having a photocatalytic function, wherein the portion of the effective surface that is not covered with the photocatalyst coat layer is an effective portion that does not have a photocatalyst coat layer and is capable of transmitting ultraviolet rays. The photocatalyst coat layer is made of a cured product of a curable composition, the cured product comprising an inorganic binder having transparency to ultraviolet light and excitation light of the photocatalytic material, and a photocatalytic material or a precursor thereof. The ultraviolet transmissive window material which has a photocatalytic function according to claim 1. A concave recess having an opening corresponding to the shape of the photocatalyst coat layer is formed on the surface of the outer surface of the window material main body, and the photocatalyst coat layer is formed in close contact with the concave recess. The ultraviolet transmissive window material having a photocatalytic function according to claim 1 or 2, wherein The ultraviolet transmissive window material having a photocatalytic function according to claim 3, wherein an outer surface of the window material is a flat surface or a smooth curved surface. The ultraviolet transmissive window material having a photocatalytic function according to claim 3 or 4, wherein the concave depression is expanded in the depth direction. The transmittance for ultraviolet rays having a wavelength corresponding to a main peak when ultraviolet rays having a single or plural peaks in a wavelength region of 200 nm to 400 nm are transmitted is 30.0% or more and 99.5% or less. The ultraviolet transmissive window material which has a photocatalytic function as described in any one of thru | or 5. It has a light source which radiates | emits an ultraviolet-ray, and a casing which has a window part, The said light source is accommodated in this casing, The said window part has a photocatalytic function as described in any one of Claims 1 thru | or 6. An ultraviolet irradiating device comprising an ultraviolet transmissive window material. The light source that emits ultraviolet light and excitation light of the photocatalytic substance is used as the light source, or another light source that emits excitation light of the photocatalytic substance together with the light source is housed in the casing. UV irradiation equipment.

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