Photocatalyst module and air treatment device

Abstract

To provide a photocatalyst module capable of improving the treatment performance in air treatment using a photocatalyst module.SOLUTION: According to an embodiment, the photocatalyst module includes a substrate and a photocatalyst. The substrate has a first major surface and a second major surface facing away from the first major surface. The substrate has through-holes penetrating from the first major surface to the second major surface. The photocatalyst is supported on the substrate. In the through-holes, a hole tapered portion is formed such that the cross-sectional area of the through-hole increases toward the second major surface over at least part of the region between the first and second major surfaces.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE Embodiments of the present invention relate to photocatalytic modules and air treatment devices. [Background technology]

[0002] An air treatment device that uses a photocatalyst module to perform air treatment is known. In such an air treatment device, a treatment space in which a photocatalyst module is stored is formed inside a housing, and the treatment space opens to the outside at each of an intake port and an exhaust port. When performing air treatment, an air flow from the intake port to the exhaust port is generated in the treatment space. As a result, air is introduced into the treatment space from the outside of the housing through the intake port. In the treatment space, light such as ultraviolet light or visible light is irradiated onto the photocatalyst module, whereby products such as active oxygen and OH radicals are generated in the photocatalyst module. Then, the air introduced into the treatment space is sterilized, deodorized, etc. using the products of the photocatalyst module, and the air that has been subjected to air treatment such as sterilization and deodorization is discharged to the outside of the housing through the exhaust port.

[0003] In the air treatment device as described above, it is required to improve the sterilization performance and deodorization performance by improving the configuration of the photocatalyst module, etc. In other words, it is required to improve the treatment performance in air treatment using the photocatalyst module. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-511161 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the present invention is to provide a photocatalyst module and an air treatment device that can improve the treatment performance in air treatment using a photocatalyst module. [Means for solving the problem]

[0006] According to the embodiment, the photocatalyst module includes a substrate and a photocatalyst, and the substrate includes a first main surface and a second main surface facing the opposite side to the first main surface. In the substrate, a through hole penetrates from the first main surface to the second main surface, and the photocatalyst is supported on the substrate. In the through hole, a hole taper portion is formed in which the cross-sectional area of ​​the through hole increases toward the second main surface over at least a part of the range between the first main surface and the second main surface. Effect of the Invention

[0007] According to the present invention, it is possible to provide a photocatalyst module and an air treatment device that can improve the treatment performance in air treatment using a photocatalyst module. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of an air treatment device according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view showing the photocatalyst module according to the first embodiment. [Diagram 3] FIG. 3 is a plan view showing the photocatalyst module according to the first embodiment, as viewed from one side in the thickness direction. [Figure 4] FIG. 4 is a cross-sectional view showing the photocatalyst module according to the first embodiment, taken along a cross section perpendicular or substantially perpendicular to the depth direction. [Diagram 5] FIG. 5 is a schematic diagram showing some of the multiple through-holes formed in the substrate in the photocatalyst module according to the first embodiment, as viewed from one side in the thickness direction. [Figure 6]FIG. 6 is a schematic diagram showing a cross section perpendicular or substantially perpendicular to the depth direction of some of the multiple through-holes formed in the substrate in the photocatalyst module according to the first embodiment. [Figure 7] FIG. 7 is a schematic diagram showing a part of a plurality of through-holes formed in a substrate in a photocatalyst module according to a first modified example, in a cross section perpendicular or substantially perpendicular to the depth direction. [Figure 8] FIG. 8 is a schematic diagram showing a part of a plurality of through-holes formed in a substrate in a photocatalyst module according to a second modified example, in a cross section perpendicular or substantially perpendicular to the depth direction. [Figure 9] FIG. 9 is a schematic diagram showing a part of a plurality of through-holes formed in a substrate in a photocatalyst module according to a third modified example, in a cross section perpendicular or substantially perpendicular to the depth direction. [Figure 10] FIG. 10 is a schematic diagram showing a part of a plurality of through-holes formed in a substrate in a photocatalyst module according to a fourth modified example, in a cross section perpendicular or substantially perpendicular to the depth direction. [Figure 11] FIG. 11 is a schematic diagram showing a verification result in the verification related to the embodiment and the like. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The photocatalyst module (13) of the embodiment includes a base material (21) and a photocatalyst, and the base material (21) includes a first main surface (22) and a second main surface (23) facing the opposite side to the first main surface (22). In the base material (21), a through hole (25) penetrates from the first main surface (22) to the second main surface (23), and the photocatalyst is supported on the base material (21). In the through hole (25), a hole taper portion (31) is formed in which the cross-sectional area of ​​the through hole increases toward the second main surface (23) over at least a part of the range between the first main surface (22) and the second main surface (23). This makes it possible to increase the flow rate of air passing through the photocatalyst module (13), and to increase the irradiation area of ​​light from the light source (15) in the photocatalyst module (13). Therefore, it is possible to improve the treatment performance in air treatment using the photocatalyst module (13).

[0010] In the photocatalyst module (13) of the embodiment, a hole taper portion (31) whose cross-sectional area increases toward the second main surface (23) is formed in the through hole (25) over the entire area from the first main surface (22) to the second main surface (23). This further increases the flow rate of air passing through the photocatalyst module (13), and further increases the light irradiation area of ​​the photocatalyst module (13) by irradiating the photocatalyst module (13) with light from the side facing the second main surface (23). Therefore, the treatment performance in air treatment using the photocatalyst module (13) is further improved.

[0011] The air treatment device (1) of the embodiment includes the above-mentioned photocatalyst module (13), a housing (2), and a light source (15). A treatment space (3) in which the photocatalyst module (13) is housed is formed inside the housing (2), and the treatment space (3) opens to the outside at the intake port (5) and the exhaust port (6). In the treatment space (3), an air flow is generated that passes through the photocatalyst module (13) and travels from the intake port (5) to the exhaust port (6). The light source (15) is capable of irradiating light toward the photocatalyst module (13) in the treatment space (3). By configuring the air treatment device (1) in this way, it is possible to improve the treatment performance in air treatment using the photocatalyst module (13).

[0012] In the air treatment device (1) of the embodiment, the light source (15) irradiates light toward the photocatalyst module (13) from the side toward which the second main surface (23) faces. Therefore, the light from the light source (15) irradiates the photocatalyst module (13) in such a manner that the light irradiation area of ​​the photocatalyst module (13) is appropriately increased. As a result, in the air treatment device (1), the treatment performance of the air treatment using the light source (15) and the photocatalyst module (13) is appropriately improved.

[0013] In the air treatment device (1) of the embodiment, air flowing from the intake port (5) toward the exhaust port (6) in the treatment space (3) of the housing (2) passes through the photocatalyst module (13) from the side facing the first main surface (22) to the side facing the second main surface (23). This improves the treatment performance in air treatment in a configuration in which air flows into the photocatalyst module (13) from the side facing the first main surface (22).

[0014] In the air treatment device (1) of the embodiment, air flowing from the intake port (5) toward the exhaust port (6) in the treatment space (3) of the housing (2) passes through the photocatalyst module (13) from the side facing the second main surface (23) to the side facing the first main surface (22). This improves the treatment performance in air treatment in a configuration in which air flows into the photocatalyst module (13) from the side facing the second main surface (23).

[0015] Hereinafter, embodiments will be described with reference to the drawings.

[0016] (First embodiment) First, as an example of an embodiment, a first embodiment will be described. FIG. 1 shows an example of an air treatment device 1 according to the first embodiment. As shown in FIG. 1, the air treatment device 1 includes a housing 2, and a processing space 3 is formed inside the housing 2. For this reason, in the air treatment device 1, the housing 2 forms an exterior. The housing 2 is formed with an intake port 5 and an exhaust port 6. The processing space 3 of the housing 2 opens to the outside of the housing 2 at the intake port 5 and the exhaust port 6, respectively. In the air treatment device 1 and housing 2 of the example of FIG. 1, a height direction (direction indicated by arrow H) is defined. The intake port 5 and the exhaust port 6 are formed at positions separated from each other, and in the air treatment device 1 of the example of FIG. 1, the intake port 5 and the exhaust port 6 are disposed separated from each other in the height direction. In the example of FIG. 1, the intake port 5 is formed on one end face of the housing 2 in the height direction, and the exhaust port 6 is formed on the end face opposite the intake port 5 in the height direction.

[0017] A fan 7 is disposed in the processing space 3 of the housing 2. In the example of FIG. 1, the fan 7 is disposed facing the exhaust port 6 from the inside, and an axial flow fan, which is an exhaust fan, is used as the fan 7. When the air processing device 1 is in use, the fan 7 is driven to generate an air flow from the intake port 5 to the exhaust port 6 in the processing space 3 of the housing 2. Therefore, by driving the fan 7, air is introduced from the outside of the housing 2 through the intake port 5 into the processing space 3, and the introduced air flows from the intake port 5 to the exhaust port 6 in the processing space 3. Then, the air is exhausted from the processing space 3 to the outside of the housing 2 through the exhaust port 6.

[0018] When an air flow is formed as described above, the direction from the intake port 5 to the exhaust port 6 in the processing space 3 is the air flow direction (direction indicated by arrow F). In the example of FIG. 1, the air flow direction in the processing space 3 is along the height direction of the air processing device 1. In addition, in the processing space 3, the air flow direction, i.e., the side toward the exhaust port 6, is defined as the downstream side. In addition, in the processing space 3, the opposite direction to the air flow direction, i.e., the side toward the intake port 5, is defined as the upstream side. Hereinafter, the expressions upstream (side) and downstream (side) refer to the upstream (side) and downstream (side) with respect to the air flow.

[0019] In one example, in the processing space 3 inside the housing 2, the prefilter 12, the light shielding grill 11, the photocatalyst module 13, the light source 15, and the fan 7 are arranged in this order from the upstream side. The prefilter 12 may be arranged only on the downstream side of the light shielding grill 11, or may be arranged both upstream and downstream of the light shielding grill 11. In one example of FIG. 1, the prefilter 12 is arranged only on the downstream side of the light shielding grill 11. In one example, the fan 7 is arranged upstream of the light shielding grill 11 in the processing space 3. In this case, the fan 7 is arranged facing the intake port 5 from the inside, and an axial flow fan, which is an intake fan, is used as the fan 7. Even in a configuration in which an intake fan is used as the fan 7, an air flow from the intake port 5 to the exhaust port 6 is formed in the processing space 3 of the housing 2 by driving the fan 7.

[0020] In one example, the fan 7 may be driven to cause air to flow in the opposite direction to the air flow direction (direction indicated by arrow F) in the example of FIG. 1. In this case, the opening functioning as the intake port 5 in the example of FIG. 1 functions as an exhaust port, and the opening functioning as the exhaust port 6 in the example of FIG. 1 functions as an intake port. In one example, the fan 7 may not be provided. However, even in a configuration in which the fan 7 is not provided, an air flow from the intake port to the exhaust port is generated in the processing space 3 inside the housing 2 by operating the air processing device 1. In this case, for example, an air flow from the intake port to the exhaust port is generated by utilizing ambient wind or air movement due to heat.

[0021] The light source 15 includes a light-emitting element 16, and in the example of FIG. 1, a plurality of light-emitting elements 16 are provided in the light source 15. The light-emitting element 16 is, for example, an LED. The light source 15 may also be composed of a lamp or the like other than an LED. A gap is formed between the light source 15 and the inner surface of the housing 2. In the processing space 3 of the housing 2, air flowing toward the exhaust port 6 passes through the gap between the light source 15 and the inner surface of the housing 2. As a result, in the processing space 3, air flows downstream beyond the light source 15. In addition, in the processing space 3, the light source 15 is operated, and the light source 15 irradiates light toward the photocatalyst module (photocatalyst filter) 13.

[0022] In one example, the light source 15 irradiates ultraviolet light toward the photocatalyst module 13. In this case, if the photocatalyst included in the photocatalyst module 13 is a type that is excited by ultraviolet light, the light source 15 is equipped with an ultraviolet LED as the light emitting element 16, or is composed of a lamp that serves as an ultraviolet light source, such as a mercury lamp, a metal halide lamp, a fluorescent ultraviolet lamp, and an excimer lamp. In addition, in a configuration in which ultraviolet light is irradiated from the light source 15 toward the photocatalyst module 13, the light source 15 irradiates ultraviolet light with a peak wavelength in the range of 320 nm or more and 400 nm or less, and the light source 15 mainly irradiates the photocatalyst module 13 with UV-A. Note that, if the photocatalyst included in the photocatalyst module 13 is a type that is excited by visible light, the light source 15 may irradiate the photocatalyst module 13 with visible light instead of ultraviolet light. In this case, the light source is equipped with a visible light LED as the light emitting element 16, or is composed of a lamp that serves as a visible light source.

[0023] In the treatment space 3, ultraviolet light (mainly UV-A) or visible light is irradiated from the light source 15 to the photocatalyst module 13, whereby products such as active oxygen and OH radicals are generated in the photocatalyst module 13. Then, the products in the photocatalyst module 13 are used to sterilize and deodorize the air introduced into the treatment space 3 through the intake port 5. Then, the air that has been subjected to air treatment such as sterilization and deodorization is discharged to the outside of the housing 2 through the exhaust port 6.

[0024] In one example, the photocatalyst module 13 may be irradiated with UV-A or visible light from the light source 15, and the air flowing through the treatment space 3 may be irradiated with ultraviolet light from the light source 15 or a light source other than the light source 15. In this case, the air flowing through the treatment space 3 is irradiated with ultraviolet light having a peak wavelength in the range of 200 nm or more and 320 nm or less, and mainly UV-C is irradiated. In the treatment space 3, mainly UV-C is irradiated to the air, thereby suppressing the activity of viruses and bacteria (bacteria) contained in the air, and the air is sterilized. In this example, the photocatalyst module 13 is irradiated with light (UV-A or visible light), thereby sterilizing and deodorizing the air, and ultraviolet light (mainly UV-C) is applied to the air flowing through the treatment space 3, thereby sterilizing the air.

[0025] Here, "sterilization" means inactivating viruses and bacteria (bacteria) present in the air, and terms such as "disinfection", "sterilization" and "sterilization" can be used instead of "sterilization". Therefore, although the term "sterilization" is used in the embodiment, the term "sterilization" can be replaced with "sterilization", "sterilization" and "sterilization".

[0026] In addition, it is preferable that at least the inner surface of the housing 2 is made of a material having a high reflectance of light (ultraviolet light and visible light). In this case, examples of materials for forming the inner surface of the housing 2 include aluminum alloys and stainless steel alloys. By forming the inner surface of the housing 2 from a material having a high reflectance of light, light from the light source 15 is effectively prevented from being emitted to the outside of the housing 2.

[0027] 1, the prefilter 12 prevents dust and the like from flowing downstream beyond the prefilter 12. The light-shielding grill 11 is capable of blocking light (ultraviolet light and visible light). In the air treatment device 1, the light-shielding grill 11 blocks light emitted from the light source 15, light reflected on the inner surface of the housing 2 after being emitted from the light source 15, and the like. The light-shielding grill 11 blocks light, thereby effectively preventing light from being emitted to the outside of the housing 2 through the air intake 5 or the like.

[0028] In one example, in addition to the light shielding grill 11, a light shielding grill is arranged downstream of the light source 15. In this case, the light shielding grill is arranged between the light source 15 and the exhaust port 6 in the processing space 3 of the housing 2. By arranging the light shielding grill downstream of the light source 15, the light reflected on the inner surface of the housing 2 is blocked by the light shielding grill, and the light is effectively prevented from being emitted to the outside of the housing 2 through the exhaust port 6 or the like.

[0029] In addition, in the example of FIG. 1, the light source 15 is disposed downstream of the photocatalyst module 13, but in one example, the light source 15 may be disposed upstream of the photocatalyst module 13. In this case, light (ultraviolet light or visible light) from the light source 15 is irradiated to the photocatalyst module 13 in the treatment space 3, and air sterilization and deodorization are performed by irradiating the photocatalyst module 13 with light (UV-A or visible light). In addition, in this example, for example, a light-shielding grill is disposed between the photocatalyst module 13 and the exhaust port 6, and the light emitted from the light source 15 and the light reflected on the inner surface of the housing 2 after being emitted from the light source 15 are shielded by the light-shielding grill. This effectively prevents light from being emitted to the outside of the housing 2 through the exhaust port 6, etc.

[0030] 2 to 4 show the photocatalyst module 13. As shown in FIG. 1 to FIG. 4, the photocatalyst module 13 includes a substrate (base material) 21. The substrate 21 is formed of, for example, ceramics, metal, glass, plastic, or resin material, and examples of ceramics that are materials for forming the substrate 21 include aluminum oxide and aluminum nitride. As the ceramics, mullite (3Al2O3·2SiO2), cordierite (2MgO·2Al2O3·5SiO2), or a mixture or laminate of mullite and cordierite may be used. The photocatalyst module 13 also includes a photocatalyst (not shown), which is supported on the surface of the substrate 21. The photocatalyst supported on the substrate 21 is formed of, for example, a metal oxide such as titanium oxide or tungsten oxide.

[0031] In the photocatalyst module 13 and the base material 21, a depth direction (direction indicated by arrow X), a lateral direction (direction indicated by arrow Y) intersecting (perpendicular or approximately perpendicular) with the depth direction, and a thickness direction (direction indicated by arrows Z1 and Z2) intersecting (perpendicular or approximately perpendicular) with both the depth direction and the lateral direction are defined. In each of the photocatalyst module 13 and the base material 21, the dimension along the thickness direction is smaller than the dimension along the depth direction and the dimension along the lateral direction. Here, FIG. 2 is a perspective view, and FIG. 3 shows a state viewed from one side of the thickness direction (arrow Z2 side). Also, FIG. 4 shows a cross section perpendicular or approximately perpendicular to the depth direction, and a cross section along the thickness direction.

[0032] The base material 21 has a pair of main surfaces 22, 23. The main surface (first main surface) 22 faces one side in the thickness direction (the side indicated by the arrow Z1). In the base material 21, the main surface 22 forms an end face on one side in the thickness direction. In addition, the main surface (second main surface) 23 faces the opposite side to the main surface 22 in the thickness direction. In the base material 21, the main surface 23 forms an end face on the opposite side to the main surface 22 in the thickness direction. FIG. 3 shows a state viewed from the side where the main surface (second main surface) 23 faces in the thickness direction.

[0033] Further, a plurality of through holes 25 are formed in the base material 21. Each of the plurality of through holes 25 penetrates the base material 21 along the thickness direction from the main surface (first main surface) 22 to the main surface (second main surface) 23. Therefore, each of the through holes 25 has an opening (first opening) 26 that opens in the main surface 22 and an opening (second opening) 27 that opens in the main surface 23. Each of the through holes 25 opens at the opening 26 to one side in the thickness direction, and opens to the side toward which the main surface 22 faces. Then, each of the through holes 25 opens at the opening 27 in the thickness direction in the opposite direction to the opening direction of the opening 26, and opens to the side toward which the main surface 23 faces. When viewed from the thickness direction (the direction of the arrow Z1 or the arrow Z2), it is desirable that the opening 26 and the opening 27 at least partially overlap. When viewed from the thickness direction (the direction of arrow Z1 or arrow Z2), it is preferable that the entire area of ​​the opening 26 overlaps with the opening 27. In this case, the opening area of ​​the opening 27 is equal to or larger than the opening area of ​​the opening 26. Furthermore, by forming the through holes 25, the surface (surface area) of the base material is formed by the sum of the area of ​​the main surface (first main surface) 22 excluding the openings (first openings) 26, the area of ​​the main surface (second main surface) 23 excluding the openings (second openings) 27, the internal area of ​​the base material 21 exposed to the outside by the through holes 25, and the side area of ​​the base material 21.

[0034] 5 and 6 show an enlarged view of a portion of the plurality of through holes 25 formed in the base material 21 in the photocatalyst module 13. FIG. 5 shows a state viewed from the side where the main surface (second main surface) 23 faces in the thickness direction (in other words, a state viewed from the top side along the direction of the arrows Z1 and Z2), and FIG. 6 shows a cross section perpendicular or substantially perpendicular to the depth direction, and a cross section along the thickness direction. As shown in FIGS. 4 to 6, each of the plurality of through holes 25 is surrounded by a hole circumferential surface 28. The hole circumferential surface 28 of each of the plurality of through holes 25 is formed from the base material 21. In each of the through holes 25, the hole circumferential surface 28 is connected to the main surface 22 at the opening edge of the opening 26, and is connected to the main surface 23 at the opening edge of the opening 27. In the base material 21, the photocatalyst is supported on the main surfaces 22 and 23, and the photocatalyst is also supported on the hole circumferential surface 28 of each of the through holes 25.

[0035] Further, each of the plurality of through holes 25 has a hole tapered portion 31 formed therein, the cross-sectional area of ​​which increases from the main surface (first main surface) 22 toward the main surface (second main surface) 23. For each of the through holes 25, the cross-sectional area of ​​the through hole 25 in a cross section perpendicular or substantially perpendicular to the thickness direction of the substrate 21 is defined as the cross-sectional area. For each of the hole tapered portions 31 of the through holes 25, the cross-sectional area of ​​the through hole 25 increases continuously as it approaches the main surface 23.

[0036] 2 to 6, in each of the through holes 25, a hole taper portion 31 is formed in which the cross-sectional area increases toward the main surface 23 over the entire area from the main surface (first main surface) 22 to the main surface (second main surface) 23. Therefore, in each of the through holes 25, the cross-sectional area increases continuously toward the main surface 23 over the entire area from the main surface 22 (opening 26) to the main surface 23 (opening 27). Due to this configuration, in each of the through holes 25, the opening area at the opening 27 (main surface 23) is larger than the opening area at the opening 26 (main surface 22).

[0037] Further, in each of the plurality of through holes 25, the hole peripheral surface 28 has an inclined surface 32 inclined with respect to the thickness direction of the base material 21. In each of the through holes 25, the outer periphery of the hole tapered portion 31 is surrounded by the inclined surface 32. In the example of Figs. 2 to 6, in each of the through holes 25, the hole tapered portion 31 is formed over the entirety from the main surface 22 to the main surface 23. For this reason, in each of the hole peripheral surfaces 28 of the through holes 25, the inclined surface 32 extends over the entirety from the main surface 22 to the main surface 23, that is, over the entirety from the opening edge of the opening 26 to the opening edge of the opening 27.

[0038] Here, a central axis C is defined for the plurality of through holes 25. The central axis C of each of the through holes 25 is along the thickness direction of the base material 21. It is preferable that the central axis C passes through the center of the opening 26 and the center of the opening 27. In each of the through holes 25, the inclined surface 32 extends in a state in which it is farther away from the central axis C in the radial direction as it approaches the main surface 23 (opening 27). That is, in each of the through holes 25, the inclined surface 32 extends in a state in which it is located on the outer periphery side of the through hole 25 as it approaches the main surface 23. Therefore, in each of the through holes 25, the inclined surface 32 is inclined with respect to the thickness direction of the base material 21 at a gradient that increases the cross-sectional area of ​​the through hole 25 toward the main surface 23 (opening 27).

[0039] Since the multiple through holes 25 formed in the base material 21 have the above-mentioned configuration, the gradient angle θ of the hole tapered portion 31 (inclined surface 32) is defined for each of the through holes 25. For each of the through holes 25, the gradient angle θ corresponds to the gradient angle of the inclined surface 32 with respect to the central axis C (thickness direction of the base material 21), and corresponds to the acute angle that the inclined surface 32 forms with respect to the central axis C. Furthermore, for each of the multiple through holes 25, the angle 2θ, which is twice the gradient angle θ, becomes the taper angle of the hole tapered portion 31.

[0040] 2 to 6, in a cross section along the thickness direction, such as a cross section perpendicular or substantially perpendicular to the depth direction, the inclined surfaces 32 of each of the through holes 25 extend linearly. Therefore, in the example of Fig. 2 to 6, the gradient angle θ is constant or substantially constant throughout the entire hole taper portion 31 of each of the through holes 25, and the gradient angle θ does not change or changes very little. Therefore, in each hole taper portion 31 of the through holes 25, the cross-sectional area of ​​the through holes 25 increases toward the main surface 23 at a constant or substantially constant gradient angle θ.

[0041] 2 to 6, a hole taper portion 31 is formed in each of the through holes 25, the cross-sectional area of ​​which increases from the main surface 22 to the main surface 23. Therefore, in the example of Fig. 2 to 6, the gradient angle θ (taper angle 2θ) is constant or approximately constant from the main surface 22 (opening 26) to the main surface 23 (opening 27) in each of the through holes 25, and the gradient angle θ does not change or hardly changes. Therefore, in each of the through holes 25, the cross-sectional area of ​​the through hole 25 increases continuously from the main surface 22 to the main surface 23 at a constant or approximately constant gradient angle θ.

[0042] 2 to 4, in the base material 21, the multiple through holes 25 are arranged side by side in the lateral direction of the base material 21 at a pitch p. In addition, in the base material 21, the multiple through holes 25 are arranged side by side in the direction along the virtual line α1 at the same or approximately the same pitch p as the arrangement of the multiple through holes 25 along the lateral direction. In the base material 21, the multiple through holes 25 are arranged side by side in the direction along the virtual line α2 at the same or approximately the same pitch p as the arrangement of the multiple through holes 25 along the lateral direction. Note that the pitch p corresponds to the distance between the central axes C of two adjacent through holes 25 in the row in which the multiple through holes 25 are arranged.

[0043] 2 to 4, the virtual line α1 is perpendicular or substantially perpendicular to the thickness direction of the substrate 21, and is inclined at 60° or substantially 60° with respect to the lateral direction of the substrate 21. The virtual line α2 is perpendicular or substantially perpendicular to the thickness direction of the substrate 21, and is inclined at 60° or substantially 60° with respect to the lateral direction of the substrate 21 to the side opposite to the side to which the virtual line α1 is inclined. For this reason, in the example of FIGS. 2 to 4, the multiple through holes 25 are arranged in an array similar to a so-called "60° staggered" array.

[0044] The arrangement of the plurality of through holes 25 in the base material 21 is not limited to the arrangement in the example of Fig. 2 to Fig. 4. As described above, if the plurality of through holes 25 are formed in the base material 21 and each of the through holes 25 is formed with a hole taper portion 31 whose cross-sectional area increases toward the main surface 23, the arrangement of the plurality of through holes 25 in the base material 21 can be changed to an appropriate arrangement and position. In one example, the plurality of through holes 25 are arranged in an arrangement similar to a so-called "parallel type". In this case, in the base material 21, the plurality of through holes 25 are arranged side by side in the horizontal direction at a pitch p, and the plurality of through holes 25 are arranged side by side in the depth direction at a pitch p that is the same or substantially the same as the arrangement of the plurality of through holes 25 along the horizontal direction.

[0045] 2 to 6, the cross-sectional shape of each of the plurality of through holes 25 is circular or substantially circular in a cross section perpendicular or substantially perpendicular to the thickness direction of the base material 21. However, the cross-sectional shape of each of the plurality of through holes 25 may be a shape other than a circle, such as an ellipse or a polygon. However, in each of the plurality of through holes 25, even when the cross-sectional shape is a shape other than a circle, a hole tapered portion 31 whose cross-sectional area increases toward the main surface (second main surface) 23 is formed as in the example of FIGS. 2 to 6. Then, in each of the through holes 25, the outer periphery of the hole tapered portion 31 is surrounded by the inclined surface 32 of the hole circumferential surface 28, and the inclined surface 32 is extended in a state in which it becomes farther from the central axis C in the radial direction as it approaches the main surface 23 (opening 27) as in the example of FIGS. 2 to 6.

[0046] Moreover, in this embodiment, in the projection of the substrate 21 (photocatalyst module 13) from the thickness direction, the multiple through holes 25 do not overlap with each other. Therefore, the multiple through holes 25 are partitioned and isolated from each other by the substrate 21. Moreover, on the main surface (first main surface) 22, the openings (first openings) 26 of the multiple through holes 25 are partitioned from each other by the substrate 21. And, on the main surface (second main surface) 23, the openings (second openings) 27 of the multiple through holes 25 are partitioned from each other by the substrate 21.

[0047] Here, similarly to the example of FIG. 2 to FIG. 6, each of the multiple through holes 25 has a circular or substantially circular cross-sectional shape, and a hole taper portion 31 is formed over the entire area from the main surface 22 to the main surface 23. In each hole taper portion 31 of the through hole 25, the cross-sectional area of ​​the through hole 25 increases toward the main surface 23 at a constant or substantially constant gradient angle θ (taper angle 2θ). In this case, when the diameter Da of each through hole 25 at the main surface 22 (opening 26) and the dimension (thickness) t of the base material 21 along the thickness direction are defined, the diameter Db of each through hole 25 at the main surface 23 (opening 27) is expressed by formula (1). The dimension t of the base material 21 along the thickness direction is the thickness of the base material 21, and corresponds to the distance between the main surfaces 22 and 23.

[0048] In addition, the pitch p is defined as described above. In this embodiment, since the plurality of through holes 25 are partitioned from each other by the base material 21 as described above, the relationship of formula (2) is established. When the cross-sectional shape of each of the plurality of through holes 25 is an ellipse, the major axis of the ellipse of each of the through holes 25 on the main surface 22 (opening 26) is used instead of the diameter Da in formula (2). When the cross-sectional shape of each of the plurality of through holes 25 is a polygon, the length of the diagonal of each of the polygonal shapes of the through holes 25 on the main surface 22 (opening 26) is used instead of the diameter Da in formula (2).

[0049]

number

[0050] 1, in the air treatment device 1 of this embodiment, the photocatalyst module 13 is arranged in the treatment space 3 of the housing 2 with the main surface (second main surface) 23 facing the side where the light source 15 is located. Therefore, in the treatment space 3, light from the light source 15, such as ultraviolet light or visible light, is irradiated onto the photocatalyst module 13 from the side where the main surface 23 faces. In the treatment space 3, air introduced from the air intake 5 passes through the multiple through holes 25 of the photocatalyst module 13 and flows downstream.

[0051] In the example of FIG. 1, in the photocatalyst module 13 arranged in the processing space 3, the main surface (first main surface) 22 of the base material 21 faces the side where the intake port 5 is located, i.e., the upstream side. And the main surface (second main surface) 23 of the base material 21 faces the side where the exhaust port 6 is located, i.e., the downstream side. Therefore, in the example of FIG. 1, the air flowing from the intake port 5 to the exhaust port 6 in the processing space 3 passes through the photocatalyst module 13 from the side where the main surface 22 faces to the side where the main surface 23 faces. Also, in the example of FIG. 1, air flows into the photocatalyst module 13 from the side opposite to the side where the light source 15 is irradiated with light.

[0052] In one example, in the photocatalyst module 13, the main surface (first main surface) 22 of the substrate 21 faces the downstream side, and the main surface (second main surface) 23 of the substrate 21 faces the upstream side. In this case, in the processing space 3, the air flowing from the intake port 5 toward the exhaust port 6 passes through the photocatalyst module 13 from the side facing the main surface 23 to the side facing the main surface 22. However, even in this example, light from the light source 15, such as ultraviolet light or visible light, is irradiated onto the photocatalyst module 13 from the side facing the main surface (second main surface) 23. Therefore, in this example, air flows into the photocatalyst module 13 from the side where the light source 15 is irradiated with light.

[0053] As described above, in this embodiment, a hole taper portion 31 whose cross-sectional area increases toward the main surface (second main surface) 23 is formed in each of the multiple through holes 25 of the base material 21. By adopting such a configuration, the pressure loss in the photocatalyst module 13 is reduced compared to a configuration in which the cross-sectional area of ​​each of the multiple through holes 25 is constant at the opening area at the opening 26 (main surface 22). By reducing the pressure loss in the photocatalyst module 13, when air flows from the intake port 5 to the exhaust port 6 in the treatment space 3, the flow rate of air passing through the photocatalyst module 13 increases. Therefore, when air treatment such as sterilization and deodorization of air is performed using the photocatalyst module 13 and the light source 15, the number of air circulations increases. As a result, the sterilization performance and deodorization performance in the air treatment are improved, and the treatment performance in the air treatment using the photocatalyst module 13 is improved.

[0054] In addition, since the hole taper portion 31 is formed in each of the through holes 25, by irradiating the photocatalyst module 13 with light from the side facing the main surface (second main surface) 23, that is, from the side where the cross-sectional area (surface area) of the through hole 25 increases in the hole taper portion 31, the light is irradiated not only to the main surface 23 but also to the inclined surface 32 of each of the through holes 25. By irradiating the inclined surface 32 of each of the through holes 25 with light, the irradiation area of ​​the light from the light source 15 increases in the photocatalyst module 13. This improves the treatment performance in air treatment using the photocatalyst module 13.

[0055] In addition, in this embodiment, in each of the multiple through holes 25, a hole taper portion 31 whose cross-sectional area increases toward the main surface 23 is formed over the entire area from the main surface (first main surface) 22 to the main surface (second main surface) 23. Therefore, the pressure loss in the photocatalyst module 13 is further reduced, and in a state in which air flows from the intake port 5 to the exhaust port 6 in the treatment space 3, the flow rate of air passing through the photocatalyst module 13 is further increased. In addition, by adopting such a configuration, in each of the through holes 25, an inclined surface 32 is extended over the entire area from the main surface 22 to the main surface 23. Therefore, by irradiating light to the photocatalyst module 13 from the side facing the main surface 23, the light irradiation area of ​​the photocatalyst module 13 is further increased. Therefore, the treatment performance in air treatment using the photocatalyst module 13 is further improved.

[0056] Furthermore, in the air treatment device 1 of this embodiment, the light source 15 irradiates light toward the photocatalyst module 13 from the side facing the main surface (second main surface) 23. Therefore, the light from the light source 15 is irradiated onto the photocatalyst module 13 in such a way that the light irradiation area of ​​the photocatalyst module 13 is appropriately increased. As a result, in the air treatment device 1, the treatment performance in air treatment using the light source 15 and the photocatalyst module 13 is appropriately improved.

[0057] In addition, in one example of this embodiment, the air flowing from the intake port 5 to the exhaust port 6 in the processing space 3 passes through the photocatalyst module 13 from the side facing the main surface (first main surface) 22 to the side facing the main surface (second main surface) 23. In another example of this embodiment, the air flowing from the intake port 5 to the exhaust port 6 in the processing space 3 passes through the photocatalyst module 13 from the side facing the main surface 23 to the side facing the main surface 22. In this embodiment, by configuring the photocatalyst module 13 as described above, in both cases where air flows into the photocatalyst module 13 from the side facing the main surface 22 and where air flows into the photocatalyst module 13 from the side facing the main surface 23, the pressure loss in the photocatalyst module 13 is reduced and the flow rate of air passing through the photocatalyst module 13 is increased. Therefore, whether air is introduced into the photocatalyst module 13 from the side facing the main surface 22 or the side facing the main surface 23, the treatment performance in air treatment is improved.

[0058] (Modification) In the above embodiment, the gradient angle θ (taper angle 2θ) is constant or approximately constant throughout the entire hole taper portion 31 in each of the through holes 25, but is not limited thereto. In a first modified example shown in FIG. 7, the gradient angle changes in accordance with the position in the thickness direction (direction along the central axis C) of the substrate 21 in each hole taper portion 31 of the multiple through holes 25. In this modified example, the gradient angle continuously decreases toward the main surface 23 (opening 27) in each hole taper portion 31 of the through holes 25. In addition, in this modified example, in a cross section along the thickness direction, such as a cross section perpendicular or approximately perpendicular to the depth direction, each inclined surface 32 of the through holes 25 is curved. Here, FIG. 7 shows a cross section perpendicular or approximately perpendicular to the depth direction, and shows a cross section along the thickness direction.

[0059] In one modified example, the gradient angle of each of the hole taper portions 31 of the through holes 25 increases continuously toward the main surface 23 (opening 27). In another modified example, the gradient angle of each of the hole taper portions 31 of the multiple through holes 25 changes stepwise in response to the position in the thickness direction (direction along the central axis C) of the substrate 21. In this case, each of the hole taper portions 31 of the through holes 25 is divided into a plurality of regions in the thickness direction of the substrate 21. In each of the hole taper portions 31 of the through holes 25, the gradient angles are different from each other in the divided multiple regions, and the gradient angle changes at the boundaries between the multiple regions. However, in both modified examples, as in the first modified example, the gradient angle of each of the hole taper portions 31 of the multiple through holes 25 changes in response to the position in the thickness direction (direction along the central axis C) of the substrate 21.

[0060] In the first modified example, as described above, in each of the hole taper parts 31 of the plurality of through holes 25, the gradient angle changes in accordance with the position in the thickness direction of the base material 21. Even in such a configuration, in each of the hole taper parts 31 of the plurality of through holes 25, the cross-sectional area of ​​the through hole 25 increases continuously toward the main surface (second main surface) 23. Therefore, in the configuration of the first modified example, as in the above-mentioned embodiment, the pressure loss in the photocatalyst module 13 is reduced compared to a configuration in which the cross-sectional area of ​​each of the plurality of through holes 25 is constant at the opening area at the opening 26 (main surface 22). As a result, when air flows from the intake port 5 to the exhaust port 6 in the processing space 3, the flow rate of air passing through the photocatalyst module 13 increases.

[0061] Also in the first modified example etc., by irradiating the photocatalyst module 13 with light from the side facing the main surface (second main surface) 23, the light is irradiated not only to the main surface 23 but also to the inclined surfaces 32 of the through holes 25. Therefore, in the first modified example etc., as in the above-mentioned embodiment etc., the irradiation area of ​​the light from the light source 15 can be increased in the photocatalyst module 13. Therefore, in the first modified example etc., as in the above-mentioned embodiment etc., it is possible to improve the treatment performance in air treatment using the photocatalyst module 13.

[0062] In the above embodiment, in each of the through holes 25, a hole taper portion 31 whose cross-sectional area increases toward the main surface 23 is formed over the entire area from the main surface (first main surface) 22 to the main surface (second main surface) 23, but this is not limited to this. In a second modified example shown in FIG. 8, in each of the multiple through holes 25, a hole taper portion 31 whose cross-sectional area increases toward the main surface 23 is formed only over a partial range between the main surfaces 22 and 23. In this modified example, in addition to the hole taper portion 31, a uniform cross-sectional area portion 35 is formed in each of the multiple through holes 25. In each of the through holes 25, the cross-sectional area of ​​the through hole 25 becomes uniform or approximately uniform over the entire uniform cross-sectional area portion 35, and the cross-sectional area does not change or does not change much. Note that FIG. 8 shows a cross section perpendicular or approximately perpendicular to the depth direction, and shows a cross section along the thickness direction.

[0063] In this modification, in each of the plurality of through holes 25, the hole circumferential surface 28 has an extended surface 36 in addition to the inclined surface 32. In each of the through holes 25, the extended surface 36 surrounds the outer periphery of the uniform cross-sectional area portion 35. In each of the through holes 25, the extended surface 36 extends along the thickness direction of the base material 21, and extends parallel or approximately parallel to the thickness direction (central axis C) of the base material.

[0064] In this modification, in each of the through holes 25, the uniform cross-sectional area portion 35 opens at the opening 26 (main surface 22), and the hole taper portion 31 opens at the opening 27 (main surface 23). In each of the through holes 25, the hole taper portion 31 is adjacent to the uniform cross-sectional area portion 35 from the side where the main surface (second main surface) 23 is located. Due to this configuration, in each of the through holes 25, the cross-sectional area of ​​the through hole 25 at the uniform cross-sectional area portion 35 is the same or approximately the same as the opening area at the opening 26 (main surface 22). Also, in this modification, as in the above-mentioned embodiment, in the hole taper portion 31 of each of the multiple through holes 25, the cross-sectional area of ​​the through hole 25 increases toward the main surface (second main surface) 23. Therefore, in this modification, in each of the through holes 25, the opening area at the opening 27 (main surface 23) is larger than the opening area at the opening 26 (main surface 22).

[0065] In addition, in a certain modified example, similar to the second modified example, each of the plurality of through holes 25 is configured to have a uniform cross-sectional area portion 35 formed in addition to the hole tapered portion 31. However, in this modified example, in each of the through holes 25, the hole tapered portion 31 is adjacent to the uniform cross-sectional area portion 35 from the side where the main surface (first main surface) 22 is located. In this case, in each of the through holes 25, the uniform cross-sectional area portion 35 opens at the opening 27 (main surface 23), and the hole tapered portion 31 opens at the opening 26 (main surface 22). In each of the through holes 25, the cross-sectional area of ​​the through hole 25 at the uniform cross-sectional area portion 35 is the same or approximately the same as the opening area at the opening 27 (main surface 23). In this modified example, similar to the second modified example, in each of the plurality of through holes 25, a hole tapered portion 31 whose cross-sectional area increases toward the main surface 23 is formed only over a partial range between the main surfaces 22 and 23.

[0066] 8, the gradient angle is constant or approximately constant over the entire hole taper portion 31 in each of the through holes 25. However, similar to the second modified example, even when the hole taper portion 31 is formed over only a portion of the range between the main surfaces 22, 23 in each of the multiple through holes 25, the gradient angle may change in accordance with the position in the thickness direction of the substrate 21 in the hole taper portion 31 of each of the through holes 25, as described above in the first modified example, etc.

[0067] As in the second modified example, even in a configuration in which the hole taper portion 31 is formed only over a part of the range between the main surfaces 22 and 23 in each of the through holes 25, the cross-sectional area of ​​the through holes 25 increases continuously toward the main surface (second main surface) 23 in the hole taper portion 31 of each of the plurality of through holes 25. Therefore, in the configuration of the second modified example, the pressure loss in the photocatalyst module 13 is reduced compared to a configuration in which the cross-sectional area of ​​each of the plurality of through holes 25 is constant at the opening area at the opening 26 (main surface 22) as in the above-mentioned embodiment. As a result, the flow rate of air passing through the photocatalyst module 13 increases when air flows from the intake port 5 to the exhaust port 6 in the processing space 3.

[0068] Also in the second modified example etc., by irradiating the photocatalyst module 13 with light from the side facing the main surface (second main surface) 23, the light is irradiated not only to the main surface 23 but also to the inclined surfaces 32 of the through holes 25. Therefore, in the second modified example etc., as in the above-mentioned embodiment etc., the irradiation area of ​​the light from the light source 15 can be increased in the photocatalyst module 13. Therefore, in the second modified example etc., as in the above-mentioned embodiment etc., it is possible to improve the treatment performance in air treatment using the photocatalyst module 13.

[0069] In the third modified example shown in Fig. 9, similarly to the second modified example, each of the through holes 25 has a hole taper portion 31 formed only over a partial range between the main surfaces 22, 23. However, in this modified example, each of the multiple through holes 25 has a reverse hole taper portion 37 formed instead of the uniform cross-sectional area portion 35. In the reverse hole taper portion 37 of each of the multiple through holes 25, the cross-sectional area of ​​the through hole 25 continuously decreases toward the main surface (second main surface) 23. Note that Fig. 9 shows a cross section perpendicular or substantially perpendicular to the depth direction, and shows a cross section along the thickness direction.

[0070] In this modification, in each of the plurality of through holes 25, the hole circumferential surface 28 has a reverse inclined surface 38 in addition to the inclined surface 32. In each of the through holes 25, the reverse inclined surface 38 surrounds the outer periphery of the hole reverse tapered portion 37. In each of the through holes 25, the reverse inclined surface 38 extends in a state in which it approaches the central axis C in the radial direction as it approaches the main surface 23 (opening 27). Therefore, in each of the through holes 25, the reverse inclined surface 38 is inclined with respect to the thickness direction of the substrate 21 at a gradient that reduces the cross-sectional area of ​​the through hole 25 toward the main surface 23 (opening 27).

[0071] In this modification, in each of the through holes 25, the hole reverse taper portion 37 opens at the opening 26 (principal surface 22), and the hole taper portion 31 opens at the opening 27 (principal surface 23). In each of the through holes 25, the hole taper portion 31 is adjacent to the hole reverse taper portion 37 from the side where the principal surface (second principal surface) 23 is located. Due to this configuration, in each of the through holes 25, the opening area at the opening 26 (principal surface 22) and the opening area at the opening 27 (principal surface 23) are each larger than the cross-sectional area of ​​the through hole 25 at the boundary between the hole taper portion 31 and the hole reverse taper portion 37.

[0072] In the third modified example, the gradient angle is constant or approximately constant throughout the hole taper portion 31 in each of the through holes 25. In addition, the gradient angle is constant or approximately constant throughout the hole reverse taper portion 37 in each of the through holes 25. However, as in the third modified example, even when the hole taper portion 31 and the hole reverse taper portion 37 are formed in each of the multiple through holes 25, the gradient angle may change in the hole taper portion 31 of each of the through holes 25 in accordance with the position in the thickness direction of the substrate 21, as described above in the first modified example. Also, in the hole reverse taper portion 37 of each of the through holes 25, the gradient angle may change in accordance with the position in the thickness direction of the substrate 21.

[0073] As in the third modified example, even in the configuration in which the hole taper portion 31 and the hole reverse taper portion 37 are formed in each of the through holes 25, the cross-sectional area of ​​the through holes 25 increases continuously toward the main surface (second main surface) 23 in the hole taper portion 31 of each of the plurality of through holes 25. Therefore, in the configuration of the third modified example, the pressure loss in the photocatalyst module 13 is reduced compared to the configuration in which the cross-sectional area of ​​each of the plurality of through holes 25 is constant at the cross-sectional area at the boundary between the hole taper portion 31 and the hole reverse taper portion 37, as in the above-mentioned embodiment. As a result, the flow rate of air passing through the photocatalyst module 13 increases when air flows from the intake port 5 to the exhaust port 6 in the processing space 3.

[0074] Also in the third modified example etc., by irradiating the photocatalyst module 13 with light from the side facing the main surface (second main surface) 23, the light is irradiated not only to the main surface 23 but also to the inclined surfaces 32 of the through holes 25. Therefore, in the third modified example etc., as in the above-mentioned embodiment etc., the irradiation area of ​​the light from the light source 15 can be increased in the photocatalyst module 13. Therefore, in the third modified example etc., as in the above-mentioned embodiment etc., it is possible to improve the treatment performance in air treatment using the photocatalyst module 13.

[0075] In the fourth modified example shown in FIG. 10, similarly to the third modified example, a hole taper portion 31 and a hole reverse taper portion 37 are formed in each of the through holes 25. However, in this modified example, in each of the through holes 25, the hole taper portion 31 is adjacent to the hole reverse taper portion 37 from the side where the main surface (first main surface) 22 is located. In this case, in each of the through holes 25, the hole reverse taper portion 37 opens at the opening 27 (main surface 23), and the hole taper portion 31 opens at the opening 26 (main surface 22). Due to this configuration, in each of the through holes 25, the cross-sectional area of ​​the through hole 25 at the boundary between the hole taper portion 31 and the hole reverse taper portion 37 is larger than the opening area at the opening 26 (main surface 22) and the opening area at the opening 27 (main surface 23). Note that FIG. 10 shows a cross section perpendicular or substantially perpendicular to the depth direction, and shows a cross section along the thickness direction.

[0076] In the fourth modified example, the gradient angle is constant or approximately constant throughout the hole taper portion 31 in each of the through holes 25. In addition, the gradient angle is constant or approximately constant throughout the hole reverse taper portion 37 in each of the through holes 25. However, as in the fourth modified example, even when the hole taper portion 31 and the hole reverse taper portion 37 are formed in each of the multiple through holes 25, the gradient angle may change in the hole taper portion 31 of each of the through holes 25 in accordance with the position in the thickness direction of the substrate 21, as described above in the first modified example. Also, in the hole reverse taper portion 37 of each of the through holes 25, the gradient angle may change in accordance with the position in the thickness direction of the substrate 21.

[0077] Even in a configuration similar to the fourth modified example, the cross-sectional area of ​​each of the multiple through holes 25 increases continuously toward the main surface (second main surface) 23 in the hole taper portion 31 of each of the multiple through holes 25. Therefore, in the configuration of the fourth modified example, the pressure loss in the photocatalyst module 13 is reduced compared to a configuration in which the cross-sectional area of ​​each of the multiple through holes 25 is constant at the opening area at the opening 26 (main surface 22), as in the above-mentioned embodiment. As a result, when air flows from the intake port 5 to the exhaust port 6 in the processing space 3, the flow rate of air passing through the photocatalyst module 13 increases.

[0078] Also in the fourth modified example, by irradiating the photocatalyst module 13 with light from the side facing the main surface (second main surface) 23, the light is irradiated to each inclined surface 32 of the through hole 25 in addition to the main surface 23. In particular, in the configuration of the fourth modified example, by irradiating the photocatalyst module 13 with light from the side facing the main surface (second main surface) 23, the light that enters the photocatalyst module 13 in a state inclined with respect to the central axis C (thickness direction of the base material 21) of the through hole 25 is irradiated to each inclined surface 32 of the through hole 25. Therefore, in the fourth modified example, as in the above-mentioned embodiment, the irradiation area of ​​the light from the light source 15 can be increased in the photocatalyst module 13. Therefore, in the fourth modified example, as in the above-mentioned embodiment, the treatment performance in air treatment using the photocatalyst module 13 can be improved.

[0079] (Verification related to implementation form, etc.) In addition, the following verification was performed as a verification related to the above-mentioned embodiment. In the verification, a photocatalyst module was formed by supporting a photocatalyst on a substrate. The substrate used had a depth dimension and a width dimension of 100 mm each, and a thickness dimension of 8 mm. The substrate had a pair of main surfaces, a first main surface corresponding to the above-mentioned main surface 22, and a second main surface corresponding to the above-mentioned main surface 23.

[0080] In addition, a plurality of through holes were formed in the substrate, and each of the plurality of through holes was made to penetrate the substrate along the thickness direction from the first main surface to the second main surface. 607 through holes were formed in the substrate. In addition, the plurality of through holes formed in the substrate were arranged in the same arrangement as the so-called "60° staggered arrangement." Therefore, the plurality of through holes were formed in the substrate without overlapping with each other when projected onto the substrate in the thickness direction.

[0081] In the row in which the plurality of through holes are arranged, the aforementioned pitch p is set to 4.17 mm. Each of the plurality of through holes is formed to have a circular cross-sectional shape in a cross section perpendicular to the thickness direction of the substrate. In the opening of the first main surface, each of the plurality of through holes has a diameter (corresponding to the aforementioned diameter Da) of 3.1 mm.

[0082] In the verification, a photocatalyst module was formed in each of the examples and comparative examples. In the examples, similar to the above-mentioned embodiment, a hole tapered portion in which the cross-sectional area increases toward the second main surface was formed in each of the multiple through holes. In each of the multiple through holes, a hole tapered portion was formed over the entire area from the first main surface to the second main surface. Therefore, in the photocatalyst module of the example, in each of the through holes, the cross-sectional area increases continuously toward the second main surface over the entire area from the first main surface to the second main surface. And, in each of the multiple through holes, the diameter at the opening of the second main surface was larger than the diameter at the opening of the first main surface. In addition, in each hole tapered portion of the through holes, the gradient angle (corresponding to the gradient angle θ described above) was constant at 3°.

[0083] In the comparative example, each of the multiple through holes was formed to have a uniform cross-sectional area from the first main surface to the second main surface, and therefore each of the multiple through holes had a uniform diameter of 3 mm from the first main surface to the second main surface.

[0084] In the verification, in each of the examples and the comparative examples, an air flow was generated and the air was made to flow through the photocatalyst module. At this time, the air was made to flow in a state where it passed through the photocatalyst module from the side facing the first main surface to the side facing the second main surface. Therefore, in the air flow generated in each of the examples and the comparative examples, the side facing the first main surface was the upstream side, and the side facing the second main surface was the downstream side.

[0085] In the verification, in each of the examples and the comparative examples, the air pressure upstream of the photocatalyst module and the air pressure downstream of the photocatalyst module were measured while generating the air flow as described above. Then, for each of the examples and the comparative examples, the pressure loss in the photocatalyst module was calculated based on the pressure measurement results.

[0086] In addition, in the verification, for each of the examples and comparative examples, the light irradiation area of ​​the photocatalyst module was calculated when light was irradiated from the side facing the second principal surface. At this time, the light irradiation area was calculated assuming that light parallel to the thickness direction of the base material (the central axis of the through hole) was incident on the photocatalyst module.

[0087] FIG. 11 shows the results of the verification in the verification related to the embodiment and the like. As shown in FIG. 11, the pressure loss in the photocatalyst module in the comparative example was 7.28 Pa, whereas the pressure loss in the photocatalyst module in the example was 5.30 Pa. That is, the pressure loss in the photocatalyst module in the example was reduced compared to the comparative example. Therefore, it was demonstrated that the pressure loss in the photocatalyst module was reduced by forming a hole tapered portion whose cross-sectional area increases toward the second main surface in each of the multiple through holes of the substrate.

[0088] In addition, as shown in FIG. 11, in the comparative example, the light irradiation area of ​​the photocatalyst module was 4581 mm 2 In the example, the light irradiation area of ​​the photocatalyst module was 7395 mm 2 That is, in the embodiment, the light irradiation area of ​​the photocatalyst module was increased when light was irradiated from the side facing the second main surface, compared to the comparative example. Therefore, it was demonstrated that the light irradiation area of ​​the photocatalyst module was increased by irradiating light from the side facing the second main surface in a configuration in which a hole tapered portion whose cross-sectional area increases toward the second main surface is formed in each of the multiple through holes of the substrate.

[0089] According to at least one of these embodiments, in the base material, each of the plurality of through holes penetrates from the first main surface to the second main surface, and in each of the plurality of through holes, a hole taper portion whose cross-sectional area increases toward the second main surface is formed over at least a portion of the range between the first main surface and the second main surface. This makes it possible to provide a photocatalyst module and an air treatment device that can improve the treatment performance in air treatment using the photocatalyst module.

[0090] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0091] 1...air treatment device, 2...housing, 3...treatment space, 5...air intake port, 6...exhaust port, 13...photocatalyst module, 15...light source, 21...substrate, 22...main surface (first main surface), 23...main surface (second main surface), 25...through hole, 31...hole tapered portion.

Claims

1. a substrate having a first main surface and a second main surface facing an opposite side to the first main surface, the substrate having a through hole extending from the first main surface to the second main surface; A photocatalyst supported on the substrate; Equipped with In the through hole, a hole taper portion is formed over at least a portion of a range between the first main surface and the second main surface, in which a cross-sectional area of ​​the through hole increases toward the second main surface. Photocatalytic module.

2. The photocatalyst module of claim 1 , wherein the through hole has a hole taper portion formed throughout the entire area from the first main surface to the second main surface, the hole taper portion increasing in cross-sectional area toward the second main surface.

3. A photocatalytic module according to claim 1 or 2; A housing in which a processing space in which the photocatalyst module is housed is formed, the processing space being open to the outside at an intake port and an exhaust port, and an air flow passing through the photocatalyst module from the intake port to the exhaust port is generated in the processing space; a light source capable of irradiating light toward the photocatalyst module in the treatment space; An air treatment device comprising:

4. The air treatment device according to claim 3 , wherein the light source irradiates the light toward the photocatalyst module from a side toward which the second main surface faces.

5. The air treatment device of claim 3 , wherein in the treatment space of the housing, the air flowing from the intake port to the exhaust port passes through the photocatalyst module from the side facing the first main surface to the side facing the second main surface.

6. The air treatment device of claim 3 , wherein in the treatment space of the housing, the air flowing from the intake port to the exhaust port passes through the photocatalyst module from the side facing the second main surface to the side facing the first main surface.

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