Wet area device

Abstract

Provided is a wet area device characterized by comprising an irradiation device that emits light and a sterilization unit that performs sterilization with the light emitted from the irradiation device, wherein: the light emitted from the irradiation device has a peak wavelength at least at 350-450 nm in the spectrum thereof; and some of the light emitted from the irradiation device passes through a surface of the sterilization unit and is reflected inside the sterilization unit.

Description

Plumbing fixtures

[0001] Aspects of the present invention generally relate to plumbing equipment.

[0002] A toilet system is known that disinfects the disinfection area using light emitted from an irradiation device (Patent Document 1).

[0003] Patent No. 6168468

[0004] The toilet device described in Patent Document 1 can only disinfect the disinfection section equipped with a photocatalytic layer, so there is a risk that it may not be able to disinfect efficiently.

[0005] The aspects of the present invention are based on the recognition of the above problems and aim to provide a water-related device that can efficiently disinfect.

[0006] The first invention is a water-related device comprising an irradiation device that irradiates light, and a sterilization unit that is sterilized by the light irradiated from the irradiation device, wherein the light irradiated from the irradiation device has a peak wavelength between 350 nm and 450 nm in its spectrum, and a portion of the light irradiated from the irradiation device passes through the surface of the sterilization unit and is reflected inside the sterilization unit.

[0007] This water-related device allows for efficient disinfection of the disinfection area because light can be irradiated from both sides onto the bacteria in the disinfection area.

[0008] The second invention is a water-related device in the first invention, characterized in that, in the light irradiated from the irradiation device, the radiant flux in the wavelength range that reflects the sterilization unit is greater than the radiant flux in the wavelength range that is absorbed by the sterilization unit.

[0009] This water-based device allows for more efficient disinfection of the surface of the disinfecting unit by reflecting most of the light that passes through it.

[0010] The third invention is that, in the first invention, the irradiance of the light irradiated from the irradiation device to the sterilization unit is 0.1 mW / cm². ２ The plumbing device is characterized by the above features.

[0011] This plumbing device ensures the disinfection performance of the disinfection unit.

[0012] The fourth invention is a plumbing device characterized in that, in the first invention, the light emitted from the irradiation device has a wavelength range of 350 nm to 450 nm.

[0013] This water-related device uses a light wavelength range suitable for generating reactive oxygen species, which are produced when light is shone on porphyrins contained within bacteria, thereby emitting light that is more effective for sterilization.

[0014] The fifth invention is a water-related device in which, in the first invention, the sterilization unit has a diffuse reflectance greater than the specular reflectance.

[0015] This water-based device can alleviate the constraints on the direction of reflection caused by the direction of light incidence. By making it easier for light irradiated onto the surface of the disinfecting unit to diffusely reflect, disinfection can be performed over a wider area.

[0016] The sixth invention is a water-related device in which, in the first invention, the sterilization unit has a reflectivity greater than its absorption rate.

[0017] This water-based device allows for more efficient disinfection of the surface of the disinfecting unit by reflecting most of the light irradiated onto its surface.

[0018] The seventh invention is a water-related device characterized in that, in the first invention, the sterilization section is composed of two or more layers, and the permeability of the surface layer is greater than that of the inner layer.

[0019] This water-related device efficiently disinfects the surface by creating a multi-layered disinfection section that allows the irradiated light to penetrate the surface layer and reflect off the inner layer.

[0020] The eighth invention is a water-related device characterized in that, in the first invention, the sterilization section is composed of two or more layers, and the reflectance of the inner layer is greater than that of the surface layer.

[0021] According to this plumbing device, the surface layer increases the rate of transmission and absorption by lowering its reflectivity, while the inner layer decreases the rate of transmission and absorption by increasing its reflectivity. This allows for efficient disinfection of the surface layer.

[0022] The ninth invention is a water-related device characterized in that, in any one of the first to eighth inventions, the sterilization unit is made of a transparent or translucent organic material to which a reflective material has been added.

[0023] This water-related device allows for the sterilization of organic materials (for example, resin materials) by shining light from both sides onto the surface of the sterilization unit to eliminate bacteria attached to it.

[0024] The tenth invention is a water-related device characterized in that, in any one of the first to eighth inventions, the sterilization unit is provided with a glassy material on top of a ceramic material.

[0025] This plumbing device allows for the sterilization of ceramic surfaces by shining light from both sides onto the surface of the sterilization unit to eliminate bacteria attached to the surface.

[0026] The eleventh invention is a water-related device characterized in that, in any one of the first to eighth inventions, the sterilization unit is made of a resin material.

[0027] This water-related device allows for the sterilization of resin materials by shining light from both sides onto bacteria attached to the surface of the sterilization unit.

[0028] The twelfth invention is that, in the eleventh invention, the irradiance of the light irradiated to the sterilization unit is 55 mW / cm². ２ The following are the characteristics of the plumbing device.

[0029] This water-related device ensures the sterilization performance of resin materials while suppressing the deterioration and heating of resin materials caused by irradiated light.

[0030] According to an aspect of the present invention, a water-related device that can efficiently disinfect can be provided.

[0031] This is a perspective view showing a toilet device, which is an example of a water-related device according to the first embodiment of the present invention. This is a cross-sectional view showing the state of light irradiated from the irradiation device. This is a graph showing the relationship between the wavelength and radiant flux of light irradiated from the irradiation device. This is an explanatory diagram showing the sterilization mode of the sterilization unit. This is a graph showing the relationship between light absorbed and reflected by the sterilization unit. This is an explanatory diagram showing a sterilization unit according to the second embodiment of the present invention. This is a graph showing the relationship between light absorbed and reflected by the sterilization unit. This is a graph showing the sterilization effect at the irradiance of light irradiated from the irradiation device. This is a graph showing the degree of resin degradation at the irradiance of light irradiated from the irradiation device.

[0032] Embodiments of the present invention will be described below with reference to Figures 1 to 9. Figure 1 is a perspective view showing a toilet device, which is an example of a water-related device according to the first embodiment of the present invention. Figure 2 is a cross-sectional view showing the state of light emitted from an irradiation device.

[0033] As shown in Figure 1, the toilet system 1 comprises a toilet bowl 2, a sanitary washing device 10 installed on top of the toilet bowl 2, and an irradiation device 30 that irradiates the toilet bowl 2 and the sanitary washing device 10 with light (germ-killing light) to disinfect them. The toilet system 1 constitutes the water-related equipment of the present invention. Note that the water-related equipment is not limited to the toilet system 1, but may be various types of equipment installed in houses and other buildings where bacteria tend to proliferate, such as kitchens and bathrooms.

[0034] Toilet 2 is a so-called seated toilet. Toilet 2 has a bowl portion 2a for receiving waste. The sanitary flushing device 10 has a casing 11, a toilet seat 13, and a toilet lid 15. The toilet seat 13 and the toilet lid 15 are pivotally supported relative to the casing 11.

[0035] In this specification, the directions viewed from the perspective of a user seated on the toilet seat 13 with their back to the toilet lid 15 are described as "up," "down," "front," "back," "right," and "left," respectively.

[0036] The casing 11 has a case plate 11a and a case cover 11b that covers the case plate 11a. Inside the casing 11, there are built-in a body washing function unit that realizes washing of a user's "buttocks" and the like when sitting on the toilet seat 13, a toilet lid opening / closing function unit that detects the opening / closing state of the toilet lid 15, and a human body detection sensor that detects a user existing around the toilet device 1, etc.

[0037] Also, for example, inside the casing 11, there is provided a seating detection sensor (not shown) that detects a user's seating on the toilet seat 13. When the seating detection sensor detects a user sitting on the toilet seat 13, if the user operates an operation unit 4 such as a remote control, etc., a local washing nozzle 20 that forms part of the body washing function unit can be advanced into the bowl portion 2a of the toilet 2 or retracted from the inside of the bowl portion 2a. In FIG. 1, the state where the local washing nozzle 20 has advanced into the bowl portion 2a is shown.

[0038] The irradiation device 30 is provided on the back surface 15a of the toilet lid 15. The irradiation device 30 has a light source 31 that irradiates light. The light irradiated from the light source 31 is sterilizing light that sterilizes bacteria and mold (hereinafter collectively referred to as bacteria) adhering to the target (sterilization part).

[0039] The irradiation device 30 has, for example, at least one light source 31. The light source 31 may be one or a plurality. The light source 31 is, for example, an LED (Light Emitting Diode). The light source 31 is not limited to an LED, and may be, for example, an LD (Laser Diode), an OLED (Organic Light Emitting Diode), etc. Also, the irradiation device 30 may use a cold cathode tube or a hot cathode tube. The irradiation device 30 is connected to a control unit (not shown) provided inside the casing 11, for example, and lights up and goes out based on the control of this control unit.

[0040] As shown in FIG. 2, when the toilet lid 15 is closed, the irradiation device 30 is positioned above the opening 13a of the toilet seat 13. The irradiation device 30 irradiates light toward the bowl portion 2a and the casing 11, for example, when the toilet lid 15 is in the closed state. That is, the bowl portion 2a and the casing 11 constitute the sterilization portion of the present invention. Note that the toilet seat 13 and the toilet lid 15 may also serve as the sterilization portion. In other words, the portion irradiated with light by the irradiation device 30 is the sterilization portion.

[0041] For example, bacteria adhering to the bowl portion 2a and the casing 11 are sterilized by the light irradiated from the irradiation device 30. Thereby, the growth of bacteria adhering to the bowl portion 2a and the casing 11 is suppressed. In FIG. 2, the direct light L1 of the light directly irradiated from the light source 31 of the irradiation device 30 toward the bowl portion 2a or the case cover 11b of the casing 11 is shown by a dotted line. On the other hand, the reflected light L2 of the direct light L1 irradiated to the bowl portion 2a and the case cover 11b is shown by a one-dot chain line.

[0042] As shown in FIG. 2, for example, the front surface of the case cover 11b and the bowl portion 2a irradiated by the direct light L1 are direct irradiation portions. On the other hand, for example, the back surface of the case plate 11a of the casing 11 is an indirect irradiation portion irradiated by the reflected light L2.

[0043] FIG. 3 is a graph showing the relationship between the wavelength of light irradiated from the irradiation device and the relative emission intensity.

[0044] As shown in FIG. 3, the light irradiated from the irradiation device 30 has a peak wavelength at least between 350 nm and 450 nm in the spectrum. In this example, the peak wavelength of the light irradiated from the irradiation device 30 is 405 nm.

[0045] Here, the bacteria possess photosensitizing molecules. These photosensitizing molecules are, for example, porphyrins. Porphyrins have an absorption wavelength range around 350 nm to 450 nm. Therefore, it is preferable that the light irradiated from the irradiation device 30 has a wavelength range of 350 nm to 450 nm. This allows for the efficient generation of reactive oxygen species, which are produced when light is irradiated onto the porphyrins possessed by the bacteria, and these reactive oxygen species can sterilize, kill, or inactivate the bacteria.

[0046] Furthermore, the light emitted from the irradiation device 30 includes wavelengths of 400 nm or more, which are in the visible light range. Therefore, the user can recognize whether or not the toilet equipment 1 (water supply equipment) is being disinfected by the light emitted from the irradiation device 30. It is also possible to have another irradiation device (not shown) having a peak wavelength in the wavelength range of 450 nm or more. This other irradiation device may consist of, for example, a blue LED and emit visible light. By combining the irradiation device 30 with the other irradiation device, the user can be made aware that disinfection is in progress. In this case, the radiant flux at the peak wavelength of the other irradiation device may be greater than the radiant flux at the peak wavelength of the irradiation device 30.

[0047] Next, the manner in which bacteria are eliminated in the sterilization section will be explained with reference to Figure 4. Figure 4 is an explanatory diagram showing the sterilization process in the sterilization section. Note that in Figure 4, cross-sectional hatching has been omitted for the sake of clarity.

[0048] Figure 4 shows the sterilization process when light is shone on the bowl portion 2a. In other words, the bowl portion 2a is the sterilization section. In this example, the bowl portion 2a has a multilayer structure of two or more layers (for example, a three-layer structure). The first layer 2a1 is the base layer. The base layer is, for example, ceramic.

[0049] The second layer 2a2 is a glaze layer located on top of the first layer 2a1. The third layer 2a3 is a CeFiONtect layer (CeFiONtect: registered trademark). The second layer 2a2 and the third layer are made of glass-containing material. The CeFiONtect layer is a glass layer fired onto the glaze layer.

[0050] The first layer 2a1 and the second layer 2a2 form the interior layers of the bowl portion 2a. The third layer 2a3 forms the surface layer of the bowl portion 2a. The bowl portion 2a has improved stain resistance due to the CeFiONtect layer. The bowl portion 2a has a glassy material provided on top of the ceramic.

[0051] The light emitted from the irradiation device 30 has a peak wavelength in its spectrum between 350 nm and 450 nm. By irradiating the sterilization section with light having such a peak wavelength, a portion of the light emitted from the irradiation device 30 passes through the surface of the sterilization section and is reflected inside the sterilization section.

[0052] Specifically, as shown in Figure 4, a portion of the direct light L1 irradiated from the irradiation device 30 directly hits the bacteria 100. A portion of the direct light L1 is then reflected off the surface of the third layer 2a3, becoming reflected light L2. Another portion of the direct light L1 passes through the third layer 2a3. A portion of this transmitted direct light L1 is absorbed by the second layer 2a2. A portion of the transmitted direct light L1 is then reflected inside the second layer 2a2, becoming reflected light L2.

[0053] A portion of the reflected light L2 reflected within the second layer 2a2 passes through the third layer 2a3. Another portion of the reflected light L2 reflected within the second layer 2a2 hits the bacteria 100. In this way, the bacteria 100 attached to the bowl portion 2a are irradiated from both the front and back sides. Therefore, the irradiation device 30 can efficiently disinfect the bowl portion 2a. Furthermore, by irradiating the disinfection area with light having a peak wavelength between 350 nm and 450 nm, the disinfection area can be effectively disinfected without, for example, providing a photocatalytic layer.

[0054] In the sterilization section, the transmittance of the surface layer is greater than the transmittance of the inner layer. That is, the transmittance of the CeFiONtect layer of the third layer 2a3 is greater than the transmittance of the ceramic of the first layer 2a1 and the transmittance of the glaze layer of the second layer 2a2. For the first layer 2a1, for example, the sum of the reflectance and absorptiveness is sufficiently greater than the transmittance. In this case, it is preferable that the reflectance is greater than the absorptiveness. Note that if the reflectance of the second layer 2a2 is high, the first layer 2a1 is unnecessary. For the first layer 2a1, it is more preferable that it is white or blue with a high reflectance between 350 nm and 450 nm. For the second layer 2a2, for example, the sum of the transmittance and reflectance is sufficiently greater than the absorptiveness. In this case, it is preferable that the reflectance is greater than the transmittance. For the second layer 2a2, it is more preferable that it is white or blue with a high reflectance between 350 nm and 450 nm. For the third layer 2a3, for example, the transmittance is sufficiently greater than the sum of the absorptiveness and reflectance. In this case, it is preferable that the reflectance is greater than the absorptiveness. The third layer 2a3 is preferably made of silica of higher purity. This allows for efficient disinfection of the surface layer by making the disinfection section a multi-layer structure such that the light irradiated from the irradiation device 30 penetrates the surface layer (third layer 2a3) and is reflected by the inner layer (first layer 2a1 or second layer 2a2).

[0055] Here, we will describe the measurement of the transmittance of each layer. First, the first diffuse reflectance is measured when light is shone onto the sterilization section (third layer 2a3). Next, the second diffuse reflectance is measured when light is shone onto the second layer 2a2 after scraping off the third layer 2a3. Then, the transmittance of the surface layer (third layer 2a3) can be calculated by calculating the square root of the second diffuse reflectance / first diffuse reflectance.

[0056] Furthermore, the third layer 2a3 and the second layer 2a2 are scraped, and the third diffuse reflectance is measured when light is shone toward the first layer 2a1. Then, by calculating the square root of the third diffuse reflectance / second diffuse reflectance, the transmittance of the inner layer (second layer 2a2) can be calculated. Note that the diffuse reflectance can be measured, for example, by attaching the sterilization unit to an integrating sphere.

[0057] In the light emitted from the irradiation device 30, the radiant flux in the wavelength range that reflects off the sterilization section is greater than the radiant flux in the wavelength range that is absorbed by the sterilization section. In this case, the radiant flux in the wavelength range that reflects off the sterilization section is the sum of the reflected light L2 reflected from the surface of the third layer 2a3 and the reflected light L2 reflected from inside the second layer 2a2. That is, the radiant energy of the reflected light L2 that reflects off the sterilization section is greater than the radiant energy absorbed by the sterilization section. The radiant flux can be calculated, for example, by multiplying the irradiance by the area.

[0058] Figure 5 is a graph showing the relationship between light absorbed and light reflected by the sterilization section. As shown in Figure 5, for example, light around 300 nm is almost completely absorbed inside the sterilization section. On the other hand, for light around 350 nm, the proportion of light absorbed by the sterilization section is slightly greater than the proportion of light reflected by the sterilization section. For light around 360 nm, the proportion of light absorbed and the proportion of light reflected by the sterilization section are almost equal. For light between 360 nm and 450 nm, the proportion of light reflected by the sterilization section is greater than the proportion of light absorbed.

[0059] Therefore, by increasing the amount of wavelengths in the spectrum between 360 nm and 450 nm in the light emitted from the irradiation device 30, the radiant flux in the wavelength range that reflects the sterilization area can be made greater than the radiant flux in the wavelength range that is absorbed by the sterilization area. As a result, by reflecting most of the light that passes through the surface of the third layer 2a3, the surface of the third layer 2a3 can be efficiently sterilized.

[0060] In other words, the sterilization section has a reflectance greater than its absorption rate. For example, by irradiating the sterilization section with light in the range of 350 nm to 450 nm, based on the material and material color of the sterilization section, the reflectance of the sterilization section can be made greater than its absorption rate. For example, the first layer 2a1 has a total reflectance and absorption rate that is sufficiently greater than its transmittance. In this case, it is preferable that the reflectance is greater than the absorbance. Note that if the reflectance of the second layer 2a2 is high, the first layer 2a1 is unnecessary. For the first layer 2a1, white or blue with a high reflectance of 350 nm to 450 nm is more preferable. For example, the second layer 2a2 has a total transmittance and reflectance that is sufficiently greater than its absorption rate. In this case, it is preferable that the reflectance is greater than the transmittance. For the second layer 2a2, white or blue with a high reflectance of 350 nm to 450 nm is more preferable. For example, the third layer 2a3 has a transmittance that is sufficiently greater than the sum of its absorption rate and reflectance. In this case, it is preferable that the reflectance is greater than the absorbance. The third layer 2a3 is preferably silica of higher purity.

[0061] Furthermore, the light reflected by the sterilization section is partially specularly reflected and partially diffusely reflected. The diffuse reflectance of the sterilization section is greater than its specular reflectance. The light reflected inside the sterilization section is also partially specularly reflected and partially diffusely reflected. For example, the second layer 2a2 consists of at least a transmitting material and a reflective material, and the reflective material is arranged to have an uneven surface. The direction of reflection of light reflected by the uneven surface is determined by the orientation of the irradiation surface. If there are irregularities in the surface shape, the reflected light is dispersed and becomes diffusely reflected. Specular reflectance and diffuse reflectance can be measured, for example, by attaching the sterilization section to an integrating sphere.

[0062] In the sterilization section, by making the diffuse reflectance greater than the specular reflectance, the constraint on the direction of reflection due to the direction of light incidence can be alleviated. Therefore, by making it easier for the light irradiated onto the sterilization section to be diffusely reflected, sterilization can be performed over a wider area.

[0063] Furthermore, in the sterilization section, the reflectance of the internal layer is greater than the reflectance of the surface layer. That is, in the sterilization section, the reflectance of the ceramic in the first layer 2a1 and the reflectance of the glaze layer in the second layer 2a3 are greater than the reflectance of the CeFiONtect layer in the third layer 2a3. For example, in the first layer 2a1, the sum of the reflectance and absorptiveness is sufficiently greater than the transmittance. In this case, it is preferable that the reflectance is greater than the absorptiveness. Note that if the reflectance of the second layer 2a2 is high, the first layer 2a1 is unnecessary. For the first layer 2a1, white or blue with a high reflectance between 350 nm and 450 nm is more preferable. For example, in the second layer 2a2, the sum of the transmittance and reflectance is sufficiently greater than the absorptiveness. In this case, it is preferable that the reflectance is greater than the transmittance. For the second layer 2a2, white or blue with a high reflectance between 350 nm and 450 nm is more preferable. For example, in the third layer 2a3, the transmittance is sufficiently greater than the sum of the absorptiveness and reflectance. In this case, it is preferable that the reflectance is greater than the absorptive rate. The third layer 2a3 is preferably made of silica of higher purity. Furthermore, it is preferable to use a transparent material to reduce the reflectance and absorptive rate. Silica has a high transmittance relative to its absorptive and reflectance rates. The surface layer increases the rate of transmission and absorption by lowering its reflectance. On the other hand, the inner layer decreases the rate of transmission and absorption by increasing its reflectance. This allows for efficient disinfection of the surface of the surface layer.

[0064] Here, we will describe the measurement of the reflectance of each layer. First, the first reflectance is measured when light is shone on the sterilization section (third layer 2a3). Next, the second reflectance is measured when light is shone on the second layer 2a2 after scraping off the third layer 2a3. If the second reflectance is greater than the first reflectance, it can be determined that the reflectance of the second layer 2a2 is greater than that of the third layer 2a3. The first layer 2a1 can be measured and determined in the same way.

[0065] Figure 6 is an explanatory diagram showing a sterilization unit according to a second embodiment of the present invention.

[0066] The disinfection unit 40 is made of a transparent or translucent organic material to which a reflective material 43 is added. The organic material is, for example, a resin material. The reflective material 43 is, for example, barium sulfate. The disinfection unit 40 is, for example, a toilet bowl or a casing 11 placed on top of a toilet bowl, made of a resin material.

[0067] The light emitted from the irradiation device 30 has a peak wavelength in its spectrum between 350 nm and 450 nm. By irradiating the sterilization unit 40 with light having such a peak wavelength, a portion of the light emitted from the irradiation device 30 passes through the surface 40a of the sterilization unit 40 and is reflected inside the sterilization unit 40.

[0068] Specifically, as shown in Figure 6, a portion of the direct light L1 irradiated from the irradiation device 30 directly hits the bacteria 100. A portion of the direct light L1 is then reflected by the surface 40a of the sterilization unit 40, becoming reflected light L2. Another portion of the direct light L1 passes through to the interior of the sterilization unit 40. A portion of this transmitted direct light L1 is absorbed by the sterilization unit 40. A portion of the transmitted direct light L1 is then reflected by the reflective material 43 added to the interior of the sterilization unit 40, becoming reflected light L2.

[0069] A portion of the reflected light L2 reflected inside the sterilization unit 40 is emitted from the surface 40a of the sterilization unit 40. Another portion of the reflected light L2 reflected inside the sterilization unit 40 hits the bacteria 100. In this way, the bacteria 100 attached to the sterilization unit 40 are irradiated from both the front and back sides. Therefore, the irradiation device 30 can efficiently sterilize the sterilization unit 40. Furthermore, by irradiating the sterilization unit 40 with light having a peak wavelength between 350 nm and 450 nm, the sterilization unit 40 can be effectively sterilized without, for example, providing a photocatalytic layer.

[0070] In the light emitted from the irradiation device 30, the radiant flux in the wavelength range that reflects the sterilization unit 40 is greater than the radiant flux in the wavelength range that is absorbed by the sterilization unit 40. In this case, the radiant flux in the wavelength range that reflects the sterilization unit 40 is the sum of the reflected light L2 reflected from the surface 40a of the sterilization unit 40 and the reflected light L2 reflected from inside the sterilization unit 40. That is, the radiant energy of the reflected light L2 that reflects the sterilization unit 40 is greater than the radiant energy absorbed by the sterilization unit 40. The radiant flux can be calculated, for example, by multiplying the irradiance by the area.

[0071] Preferably, the light emitted from the irradiation device 30 has a wavelength range of 350 nm to 450 nm. This allows for the efficient generation of reactive oxygen species, which are produced when light is irradiated onto the porphyrins possessed by the bacteria, and these reactive oxygen species can be used to disinfect, kill, or inactivate the bacteria.

[0072] Furthermore, if the sterilization unit 40 is made of resin material, by setting the wavelength range of light to 350 nm or more and 450 nm or less, the deterioration of the sterilization unit 40 can be suppressed compared to when light with a wavelength of less than 350 nm is irradiated onto the sterilization unit.

[0073] Furthermore, the light emitted from the irradiation device 30 includes wavelengths of 400 nm or more, which are in the visible light range. Therefore, the user can recognize whether or not the toilet equipment 1 (water-related equipment) has been disinfected by the light emitted from the irradiation device 30.

[0074] Figure 7 is a graph showing the relationship between light absorbed and reflected by the resin material (polypropylene) in the sterilization section. As shown in Figure 7, for example, light around 300 nm is almost completely absorbed inside the sterilization section 40. The reflectance increases from 300 nm to 400 nm. For light around 450 nm, the proportion of reflected light is greater than the proportion of light absorbed by the sterilization section 40.

[0075] Therefore, by increasing the amount of wavelengths in the spectrum between 400 nm and 450 nm in the light emitted from the irradiation device 30, the radiant flux in the wavelength range that reflects the sterilization unit 40 can be made greater than the radiant flux in the wavelength range that is absorbed by the sterilization unit 40. As a result, by reflecting most of the light that passes through the surface 40a of the sterilization unit 40, the surface 40a of the sterilization unit 40 can be efficiently sterilized.

[0076] In other words, the reflectivity of the sterilization unit 40 is greater than its absorption rate. For example, by irradiating the sterilization unit 40 with light in the range of 350 nm to 450 nm, based on the material and material color of the sterilization unit 40, the reflectivity of the sterilization unit 40 can be made greater than its absorption rate. For example, if the color of the sterilization unit 40 is white, the reflectivity will be high in the range of 350 nm to 450 nm. Also, within the above range, the reflectivity will be higher in the longer wavelength region. It is preferable that the peak wavelength region of the light source be in the longer wavelength region even within the range of 350 nm to 450 nm. That is, it is desirable that the peak region be in the range of 400 nm to 450 nm.

[0077] Furthermore, the light reflected by the sterilization unit 40 is partially specularly reflected and partially diffusely reflected. The sterilization unit 40 has a greater diffuse reflectance than specular reflectance. The light reflected inside the sterilization unit 40 is also partially specularly reflected and partially diffusely reflected. The sterilization unit 40 consists of at least a transmitting material and a reflective material, and the reflective material is arranged to have an uneven surface. The direction of reflection of light reflected by the uneven surface is determined by the orientation of the irradiation surface. If there are irregularities in the surface shape, the reflected light is dispersed and becomes diffusely reflected. Specular reflectance and diffuse reflectance can be measured, for example, by attaching the sterilization unit 40 to an integrating sphere.

[0078] In the sterilization unit 40, by making the diffuse reflectance greater than the specular reflectance, the constraint on the direction of reflection due to the direction of light incidence can be relaxed. Therefore, by making it easier for the light irradiated onto the sterilization unit 40 to be diffusely reflected, sterilization can be performed over a wider area.

[0079] Furthermore, the irradiance of the light emitted from the irradiation device 30 to the sterilization unit 40 is 0.1 mW / cm² when the sterilization unit 40 is made of ceramic. ２ The above is the case. The minimum irradiance value corresponds to the sterilization effect of the sterilization unit 40. On the other hand, the irradiance of the light emitted from the irradiation device 30 to the sterilization unit 40 is 0.1 mW / cm² when the sterilization unit 40 is made of resin material. ２ 55mW / cm or more ２ The maximum irradiance is a value corresponding to the degree of deterioration of the sterilization unit 40 (resin material). The degree of deterioration includes discoloration of the resin material. Because ceramics have very high thermal conductivity, localized high temperatures do not occur when sterilization is performed. Therefore, if the sterilization unit 40 is made of ceramic, it is not necessary to consider the maximum irradiance of light.

[0080] Increasing the irradiance of the light enhances the sterilization effect of the sterilization unit 40. However, increasing the irradiance of the light also accelerates the deterioration rate of the sterilization unit 40. Therefore, the irradiance of the light emitted from the irradiation device 30 is set considering the balance between the sterilization effect of the sterilization unit 40 and the rate of deterioration of the sterilization unit 40.

[0081] Figure 8 is a graph showing the sterilization effect at different irradiance levels of light emitted from the irradiation device. Figure 9 is a graph showing the degree of resin degradation at different irradiance levels of light emitted from the irradiation device.

[0082] The minimum value of the light irradiance affects the sterilization effect of the sterilization unit 40. Figure 8 shows the sterilization effect when a bacterial solution containing Methylobacterium dropped onto a resin material is irradiated with 405 nm light. As shown in Figure 8, the number of bacteria increases over time when light is not irradiated. On the other hand, at 0.1 mW / cm² ２ When irradiated with light of this intensity, the number of bacteria decreases over time. ２ The reduction in bacterial count when irradiated with light of this intensity is 0.1 mW / cm². ２ This is greater than the reduction in bacterial count when irradiated with light of the same irradiance.

[0083] The maximum value of the light irradiance affects the degree of deterioration of the sterilization unit 40. FIG. 9 is a graph showing the calculated allowable degree of deterioration (discoloration) of the sterilization unit 40. The allowable range of the degree of deterioration is set based on, for example, products of various water-related devices and the irradiation time of the irradiated light.

[0084] As shown in FIG. 9, when the sterilization unit 40 is irradiated with an irradiance of, for example, 200 mW / cm ２ for about 170 hours, it exceeds the allowable range of deterioration (discoloration) set for that product. Also, when the sterilization unit 40 is irradiated with an irradiance of 55 mW / cm ２ for about 4000 hours, it exceeds the set allowable range of deterioration (discoloration). The maximum value of the irradiance of the light irradiated from the irradiation device 30 is set based on, for example, the service life of the product.

[0085] For example, the minimum value of the light irradiance is preferably 1 mW / cm ２ or more, more preferably 10 mW / cm ２ or more. Also, for example, the maximum value of the light irradiance is preferably 30 mW / cm ２ or less, more preferably 15 mW / cm ２ or less. Thereby, while ensuring the sterilization performance of the sterilization unit 40, deterioration and heating of the sterilization unit 40 by the irradiated light can be suppressed. As a result, for example, the hygiene of the product can be improved corresponding to the service life and usage method of the product.

[0086] The embodiment may include the following configurations.

[0087] (Configuration 1) A plumbing fixture comprising: an irradiation device that irradiates light; and a sterilization unit that is sterilized by the light irradiated from the irradiation device, wherein the light irradiated from the irradiation device has a peak wavelength in the spectrum between 350 nm and 450 nm, and a portion of the light irradiated from the irradiation device is transmitted through the surface of the sterilization unit and reflected inside the sterilization unit. (Configuration 2) The plumbing fixture according to Configuration 1, wherein the radiant flux in the wavelength range that reflects the sterilization unit is greater than the radiant flux in the wavelength range that is absorbed by the sterilization unit. (Configuration 3) The irradiance of the light irradiated from the irradiation device to the sterilization unit is 0.1 mW / cm². ２ (Configuration 4) A plumbing device according to any one of Configurations 1 to 3, characterized in that the light irradiated from the irradiation device has a wavelength range of 350 nm to 450 nm. (Configuration 5) A plumbing device according to any one of Configurations 1 to 4, characterized in that the sterilization unit has a diffuse reflectance greater than the specular reflectance. (Configuration 6) A plumbing device according to any one of Configurations 1 to 5, characterized in that the sterilization unit has a reflectance greater than the absorptance. (Configuration 7) A plumbing device according to any one of Configurations 1 to 6, characterized in that the sterilization unit is composed of two or more layers, and the transmittance of the surface layer is greater than the transmittance of the inner layer. (Configuration 8) A plumbing device according to any one of Configurations 1 to 7, characterized in that the sterilization unit is composed of two or more layers, and the reflectance of the inner layer is greater than the reflectance of the surface layer. (Configuration 9) A plumbing device according to any one of Configurations 1 to 8, characterized in that the sterilization unit is made of a transparent or translucent organic material to which a reflective material has been added. (Configuration 10) The water fixture according to any one of Configurations 1 to 8, characterized in that the sterilization unit is provided with a glassy material on top of a ceramic material. (Configuration 11) The water fixture according to any one of Configurations 1 to 8, characterized in that the sterilization unit is made of a resin material. (Configuration 12) The irradiance of the light irradiated to the sterilization unit is 55 mW / cm² ２The plumbing device according to configuration 11, characterized in that it is as follows.

[0088] Embodiments of the present invention have been described above. However, the present invention is not limited to these descriptions. Modifications made by those skilled in the art to the above-described embodiments are also included within the scope of the present invention, as long as they retain the features of the present invention. For example, the shape, dimensions, materials, arrangement, and installation configuration of each element of a plumbing fixture are not limited to those exemplified and can be modified as appropriate. Furthermore, the elements of each of the above-described embodiments can be combined to the extent technically feasible, and such combinations are also included within the scope of the present invention, as long as they retain the features of the present invention.

[0089] 1 Toilet equipment 2 Toilet bowl 2a Bowl section (disinfection section) 2a1 First layer (internal layer) 2a2 Second layer (internal layer) 2a3 Third layer (surface layer) 4 Operation unit 10 Sanitary cleaning device 11 Casing 11a Case plate 11b Case cover 13 Toilet seat 13a Opening 15 Toilet lid 15a Underside 20 Local cleaning nozzle 30 Irradiation device 31 Light source 40 Disinfection section 40a Surface 43 Reflective material 100 Bacteria L1 Direct light L2 Reflected light

Claims

1. A water-related device comprising: an irradiation device that emits light; and a sterilization unit that is sterilized by the light emitted from the irradiation device, wherein the light emitted from the irradiation device has a peak wavelength in its spectrum between 350 nm and 450 nm, and a portion of the light emitted from the irradiation device passes through the surface of the sterilization unit and is reflected inside the sterilization unit.

2. The water-related equipment according to claim 1, characterized in that, in the light irradiated from the irradiation device, the radiant flux in the wavelength range that reflects the sterilization unit is greater than the radiant flux in the wavelength range that is absorbed by the sterilization unit.

3. The irradiance of the light emitted from the irradiation device to the sterilization section is 0.1 mW / cm². ２ The water supply device according to claim 1, characterized in that it is as described above.

4. The water supply device according to claim 1, characterized in that the light emitted from the irradiation device has a wavelength range of 350 nm to 450 nm.

5. The water-related device according to claim 1, characterized in that the sterilization unit has a diffuse reflectance greater than its specular reflectance.

6. The water-related device according to claim 1, characterized in that the sterilization section has a reflectivity greater than its absorption rate.

7. The water-related device according to claim 1, characterized in that the sterilization section is composed of two or more layers, and the permeability of the surface layer is greater than that of the inner layer.

8. The water-related device according to claim 1, characterized in that the disinfection section is composed of two or more layers, and the reflectance of the inner layer is greater than that of the surface layer.

9. The water-related device according to any one of claims 1 to 8, characterized in that the disinfecting section is made of a transparent or translucent organic material to which a reflective material has been added.

10. The water-related device according to any one of claims 1 to 8, characterized in that the disinfection unit has a glassy material provided on top of the ceramic.

11. The water-related device according to any one of claims 1 to 8, characterized in that the disinfecting part is made of a resin material.

12. The irradiance of the light irradiated to the sterilization unit is 55 mW / cm². ２ The plumbing device according to claim 11, characterized in that it is as follows:

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