Device for discharging reformed water, and toilet device provided with said device

Abstract

Disclosed is a device for discharging reformed water capable of suppressing hydrophobization of a hydrophilic bowl surface of a toilet bowl due to adhesion of urine-derived protein to the bowl surface, thereby maintaining hydrophilicity of the bowl surface and waste-cleaning performance of the bowl surface. The device, which is used together with a toilet bowl having a hydrophilic bowl surface and discharges reformed water onto the bowl surface, comprises a generation unit for generating reformed water, and a discharge unit for discharging the generated reformed water onto the bowl surface, and is characterized in that: when the product of the concentration of an active component contained in the reformed water and the time during which the reformed water is discharged onto the bowl surface is defined as the CT value (ppm / sec), A: the reformed water is ozone water and is discharged with a CT value of 2 ppm / sec to 100 ppm / sec inclusive, B: the reformed water is hydrogen peroxide water and is discharged with a CT value of 5 ppm / sec or more and less than 1000 ppm / sec, or C: the reformed water is free chlorine water and is discharged with a CT value of 20 ppm / sec to 300 ppm / sec inclusive.

Description

Device for discharging reformed water and toilet device equipped with said device

[0001] The present invention relates to a device for discharging modified water and a toilet apparatus equipped with the device. More specifically, the present invention relates to a device for discharging modified water that can prevent hydrophobicity of the hydrophilic bowl surface of a toilet bowl caused by adhesion of urinary proteins to the bowl surface, i.e., maintain hydrophilicity, and maintain dirt cleanability (removability) that depends on hydrophilicity, and a toilet apparatus equipped with the device. The present invention also relates to a device for discharging modified water that can preferably maintain the hydrophilicity of the bowl surface as well as the ability to remove dirt, particularly limescale containing urinary proteins, and a toilet apparatus equipped with the device.

[0002] As consumers increasingly seek clean and comfortable living environments, there is a demand for technologies that can maintain hygienic living environments. In particular, toilets require extremely high levels of hygiene, as human waste poses a high risk of infectious diseases. One known technology for sterilizing bacteria and fungi on the surface of a toilet bowl in order to maintain hygienic conditions in toilets involves electrolyzing tap water to produce and discharge modified water with sterilizing properties.

[0003] For example, Japanese Patent Laid-Open Publication No. 2019-136443 (Patent Document 1) discloses such a technology, which supplies heated free chlorine water or hydrogen peroxide water to plumbing equipment and sterilizes the equipment by bringing it into contact with the equipment. Specifically, it discloses that a variety of microbial soils can be effectively suppressed by heating hydrogen peroxide water of 1000 ppm or more or free chlorine water of 1 ppm or more to 40°C and discharging it onto the surface of the toilet bowl for 10 seconds twice a day.

[0004] Japanese Patent Laid-Open Publication No. 2016-035196 (Patent Document 2) discloses that a method of supplying ozone-free tap water to a portion of a toilet bowl to be disinfected and then supplying modified water containing ozone to that portion exhibits a higher disinfecting effect than a method of supplying only modified water to that portion. Specifically, the publication compares an example in which tap water is supplied to a test sample for 50 seconds, followed by disinfected water (ozone water prepared by dissolving approximately 2 mg / L of ozone gas in tap water) for 10 seconds after a 5-second interval, with a comparative example in which the same sample is supplied with only the same disinfected water for 60 seconds, and reveals that the example exhibits a higher disinfecting effect than the comparative example. Because a hydrophobic acrylic plate is used as the test sample in the [Example] of Patent Document 2, the disinfection technology described in this patent document is considered to be a technology that is premised on disinfecting a hydrophobic portion to be disinfected.

[0005] Japanese Patent Application Laid-Open Publication No. 2012-207461 (Patent Document 3) describes a toilet device that sprays at least one of water and hypochlorous acid water onto a hydrophilic bowl surface before using the toilet, and then sprays hypochlorous acid water onto the bowl surface after using the toilet, thereby preventing oils such as fatty acids contained in feces from adhering to the bowl surface and preventing a decrease in the cleanability of the bowl surface due to the oils.

[0006] On the other hand, there are widely known techniques for treating the surfaces of various substrates according to the intended use of the component to obtain a component with a desired function on the surface. For example, when water adhered to the surface of a wet-related component dries, limescale containing silica and calcium, which are components contained in tap water, forms on the surface. In order to improve the removability (cleanability) of limescale and dirt on the surface of the wet-related component, a technique for coating and modifying the surface of the substrate of the wet-related component with a layer or film having desired properties is known.

[0007] For example, Japanese Patent Laid-Open Publication No. 2016-020461 (Patent Document 4) describes such a technique, in which a ceramic surface is treated with a silane coupling agent (specifically, 3-acryloxypropyltrimethoxysilane) containing a radical-reactive functional group to form a hydrophobic primer layer, and a coating composition containing a hydrophilic compound containing a radical-reactive functional group and an alkali metal salt of a sulfonic acid group is applied to this primer layer to form a hydrophilic coating film on the ceramic surface via the hydrophobic primer layer. According to Patent Document 4, the resulting hydrophilic coating film is said to have good washability (stain removability, paragraphs 0084-0085).

[0008] JP 2019-136443 A JP 2016-035196 A JP 2012-207461 A JP 2016-020461 A

[0009] The present inventors have discovered that one of the fundamental causes of toilet staining caused by microorganisms, filth, and the like is the hydrophobicization of the hydrophilic surface. They also discovered a new problem: hydrophobicization of the hydrophilic surface occurs in areas directly exposed to urine even after a few to ten uses of the toilet. Furthermore, they have newly discovered that hydrophobicization of the toilet bowl occurs primarily due to the adhesion of proteins contained in urine, rather than oils contained in feces. Specifically, they have discovered a new problem that arises specifically when using a toilet with a hydrophilic bowl surface: namely, the adhesion of proteins contained in urine to the hydrophilic bowl surface causes hydrophobicity, impairing the stain removal (cleaning) ability of the bowl surface, which is dependent on its hydrophilicity (hereinafter referred to as "Problem 1"). The present inventors have then discovered a novel configuration for solving Problem 1. Specifically, Problem 1 is solved by controlling the product of the concentration of the active ingredient contained in the modified water dispensed onto the hydrophilic bowl surface of the toilet and the time the modified water is dispensed onto the bowl surface, i.e., the time the modified water is in contact with the bowl surface, within a predetermined range.

[0010] Therefore, the present invention aims to provide a device that ejects modified water that prevents the hydrophilic bowl surface of a toilet from becoming hydrophobic due to adhesion of urine-derived proteins to the bowl surface, i.e., maintains the hydrophilicity of the bowl surface, thereby enabling the bowl surface to maintain its ability to clean dirt over the long term.

[0011] Furthermore, the inventors have confirmed that when proteins contained in urine remain on the bowl surface along with tap water, limescale formed by silica and calcium contained in tap water strongly adheres (i.e., fixes) to the bowl surface in a state where it coexists with the proteins that induce hydrophobicity (e.g., in a state containing the proteins). The inventors have discovered a further novel problem: that such limescale becomes hydrophobic due to the presence of the proteins, making it difficult to remove even by cleaning on surfaces with low limescale removability, such as the surface of sanitary ware (hereinafter referred to as "Problem 2"). The inventors have then discovered a novel configuration for solving Problem 2. Specifically, Problem 2 is solved by causing specific chemical species to be present on the hydrophilic bowl surface of a toilet, i.e., by making the bowl surface hydrophilic to a specific degree, and by controlling the product of the concentration of the active ingredient contained in the modified water dispensed on the bowl surface and the time the modified water is dispensed on the bowl surface, i.e., the time the modified water is in contact with the bowl surface, within a predetermined range.

[0012] Therefore, the present invention aims to provide a device that discharges modified water that can prevent the hydrophilic bowl surface of a toilet from becoming hydrophobic due to adhesion of urinary proteins to the bowl surface, i.e., maintain the hydrophilicity of the bowl surface, and in particular, make the bowl surface specifically hydrophilic, thereby maintaining the dirt cleansing properties of the bowl surface over the long term, and in particular, even if urinary proteins remain on the bowl surface together with scale and hydrophobic scale containing the proteins adheres to the bowl surface, the scale can be removed by normal cleaning (in other words, prevent hydrophobic scale containing the proteins from adhering to the bowl surface).

[0013] As a means for solving the above-mentioned problem 1, a device for discharging modified water according to a first aspect of the present invention is a device for discharging modified water onto a bowl surface, used in conjunction with a toilet having a hydrophilic bowl surface, and comprising: a generating unit for generating modified water; and a discharging unit for discharging the generated modified water onto the bowl surface, wherein when the product of the concentration of an active ingredient contained in the modified water and the time for discharging the modified water onto the bowl surface is defined as a CT value (ppm·seconds), the device is characterized in that: A: the modified water is ozone water, and is discharged with a CT value of 2 ppm·seconds or more and 100 ppm·seconds or less; B: the modified water is hydrogen peroxide water, and is discharged with a CT value of 5 ppm·seconds or more and less than 1000 ppm·seconds; or C: the modified water is free chlorine water, and is discharged with a CT value of 20 ppm·seconds or more and 300 ppm·seconds or less.

[0014] As a means for solving the above-mentioned problem 2, i.e., as a preferred embodiment of the first embodiment of the present invention, the device for discharging modified water according to the second embodiment of the present invention is a device for discharging modified water according to the first embodiment, in which the hydrophilic bowl surface in the first embodiment is a bowl surface containing hydrophilic organic functional groups on its surface. Specifically, the device for discharging modified water according to a second aspect of the present invention is a device for discharging modified water onto a bowl surface, used in conjunction with a toilet having a bowl surface containing hydrophilic organic functional groups on its surface, and comprising: a generation unit for generating modified water; and a discharge unit for discharging the generated modified water onto the bowl surface, characterized in that, when the product of the concentration of the active ingredient contained in the modified water and the time for discharging the modified water onto the bowl surface is defined as the CT value (ppm·seconds), A: the modified water is ozone water, and is discharged with a CT value of 2 ppm·seconds or more and 100 ppm·seconds or less; B: the modified water is hydrogen peroxide water, and is discharged with a CT value of 5 ppm·seconds or more and less than 1000 ppm·seconds; or C: the modified water is free chlorine water, and is discharged with a CT value of 20 ppm·seconds or more and 300 ppm·seconds or less.

[0015] In a toilet having a hydrophilic bowl surface, contacting the bowl surface with modified water having sufficient oxidizing power for a predetermined period of time removes proteins adhering to the bowl due to urination, suppresses hydrophobicity of the toilet bowl caused by protein adhesion and drying, and maintains the hydrophilicity of the toilet. This improves the cleanability of waste. Furthermore, by setting the upper limit of the CT value of the modified water as described above, the total amount of active ingredient discharged can be reduced, thereby reducing human health risks, resin deterioration risks, and electrode load. The first and second aspects of the present invention commonly provide a new use for modified water, namely, removing proteins adhering to the toilet surface and maintaining hydrophilicity for a long period of time. Furthermore, by incorporating hydrophilic organic functional groups into the surface of the bowl surface, proteins and limescale (e.g., limescale containing protein) remaining and adhering to the surface can be removed by cleaning. According to a second aspect of the present invention, a new use of modified water is provided, which is to remove proteins adhering to the surface of a toilet bowl, particularly limescale containing said proteins, by cleaning (in other words, to prevent limescale containing said proteins from adhering to the bowl surface), and to maintain hydrophilicity for a long period of time.

[0016] 1 is a schematic diagram showing an example of an apparatus for discharging modified water according to the present invention. FIG. 2 is a schematic diagram showing an example of an apparatus for discharging modified water according to the present invention. FIG. 3 is a schematic diagram showing an example of an apparatus for discharging modified water according to the present invention. FIG. 4 is a schematic diagram showing an example of a toilet apparatus according to the present invention. FIG. 5 is a graph showing the hydrophobicity of a hydrophilic toilet bowl due to urine. (a) is a graph showing the hydrophobicity of test piece 1, and (b) is a graph showing the hydrophobicity of test piece 2. FIG. 6 is an SEM image of the surface of a sanitary ware piece to which urine has adhered and which has been dried. FIG. 7 is an EDX spectrum of the surface of a sanitary ware piece to which urine has adhered and which has been dried. FIG. 8 is an FT-IR spectrum of the surface of a sanitary ware piece to which urine has adhered and which has been dried. FIG. 9 is a diagram showing the state of immersion of a sanitary ware piece in urine. FIG. 10 is a diagram showing the state of cleaning a sanitary ware piece immersed in urine. FIG. 11 is a diagram showing the state of discharging modified water onto a sanitary ware piece to which protein has adhered. FIG. 12 is a graph showing the relationship between CT value and amount of remaining protein. 1A is a graph showing the relationship between the CT value and the amount of remaining protein for test piece 1, and FIG. 1B is a graph showing the relationship between the CT value and the amount of remaining protein for test piece 2. 1B is a perspective view showing an example of a method for measuring the particle size of mist when modified water is sprayed (misted) and ejected. 1C is an SEM image of a cross section of sanitary ware and element mapping by EDX.

[0017] Definitions In the present invention, the "CT value (ppm-seconds)" refers to the product of the concentration of the active ingredient contained in the modified water and the time the modified water is discharged onto the bowl surface of the toilet, i.e., the time the modified water is in contact with the bowl surface of the toilet. In the present invention, the term "range of ____ to ____" means that the stated upper and lower limits are also included in the range. In the present invention, unless otherwise specified, the toilet refers to a toilet bowl. In the present invention, "flushing" in flushing the toilet bowl or bowl surface, and flushing waste, refers to flushing water with the purpose of discharging waste such as feces and urine, or paper such as toilet paper, from the toilet bowl into the drain pipe.

[0018] Device for discharging reformed water The device for discharging reformed water of the present invention will be described below. However, unless otherwise specified, that is, unless "the second aspect of the present invention," "device for discharging reformed water according to the second aspect of the present invention," or equivalent descriptions are clearly stated, they are intended to explain technical matters common to the device for discharging reformed water according to the first aspect of the present invention and the device for discharging reformed water according to the second aspect of the present invention.

[0019] The device for discharging modified water of the present invention is used with a toilet having a hydrophilic bowl surface, preferably a bowl surface containing hydrophilic organic functional groups on its surface, and is a device for discharging modified water onto the bowl surface, comprising: a generation unit for generating modified water; and a discharge unit for discharging the generated modified water onto the bowl surface, wherein when the product of the concentration of an active ingredient contained in the modified water and the time for discharging the modified water onto the bowl surface is defined as a CT value (ppm-seconds), the device is characterized in that: A: the modified water is ozone water, and is discharged with a CT value of 2 ppm-seconds or more and 100 ppm-seconds or less; B: the modified water is hydrogen peroxide water, and is discharged with a CT value of 5 ppm-seconds or more and less than 1000 ppm-seconds; or C: the modified water is free chlorine water, and is discharged with a CT value of 20 ppm-seconds or more and 300 ppm-seconds or less. The device for discharging modified water of the present invention can maintain the original hydrophilicity of the bowl surface of a toilet by discharging modified water at a specific CT value onto the hydrophilic bowl surface, which becomes hydrophobic due to the adsorption of proteins derived from urine.

[0020] The modified water-dispensing device of the present invention is used together with a toilet. "Used together" means that the modified water-dispensing device is installed in a state where the modified water dispensed from the device can be applied to the bowl surface of the toilet. Preferably, the modified water-dispensing device and the toilet are directly or indirectly connected or integrated in terms of the function of suppressing hydrophobicity of the hydrophilic bowl surface by the modified water and maintaining hydrophilicity. Furthermore, "used together" preferably means that the modified water-dispensing device and the toilet are functionally linked, but the timing of their mutual operation may be appropriately controlled within a range that suppresses hydrophobicity of the hydrophilic bowl surface, i.e., maintains the hydrophilicity of the bowl surface, and there may be a time lag between their mutual operations. Note that "used together" also means that the modified water-dispensing device may exist separately from the toilet (for example, the modified water-dispensing device may be an item that is independently distributed on the market).

[0021] Mechanism of Toilet Bowl Hydrophobization and Mechanism of Toilet Bowl Hydrophilicity Maintenance (Cause of Toilet Bowl Hydrophobization) Urine contains biological proteins such as albumin, immunoglobulin G (IgG), and Tamm Horsfall protein (THP), and when urine comes into contact with the surface of the toilet bowl, these proteins are adsorbed to the surface. It is thought that the adsorbed proteins undergo a conformational change upon drying, and hydrophobic residues are oriented toward the surface, thereby hydrophobizing the toilet bowl surface. Because the hydrophobized proteins adhere to the toilet bowl surface, they cannot be removed by water flow, such as when flushing the toilet bowl. It is thought that these hydrophobized proteins become the starting point for further protein adsorption when they come into contact with urine during the next use of the toilet, thereby progressing the hydrophobization.

[0022] (Why Toilet Bowls Become Hydrophobic Even with Short Term and / or Few Uses) It is known that oils, primarily those contained in feces, float to the surface of hydrophilic surfaces due to the rolling-up effect. Meanwhile, proteins contained in urine are amphoteric molecules with positive and negative charges, possess hydrophobic groups, and readily change conformation upon contact with any material surface, leading to nonspecific adsorption even on hydrophilic surfaces. The inventors confirmed through field tests described below that a sanitary ware toilet surface with an initial water contact angle of approximately 10° becomes hydrophobic to a water contact angle of approximately 40° after just one urination, and that after approximately 10 urinations, the water contact angle becomes hydrophobic to approximately 100°. In other words, the hydrophobicization of toilet bowls and the resulting decline in fecal cleansing ability can occur within a short span of one day, depending on the toilet's usage environment, and are difficult to prevent even with regular cleaning, such as by using a detergent and brush.

[0023] According to Patent Document 3, 100 ppm of free chlorine is used to decompose oil contained in feces, but the inventors have confirmed that the effect of suppressing hydrophobicity caused by proteins contained in urine is sufficient with the concentration and amount (discharge time) of modified water required to decompose the oil, i.e., less than a few tenths of the CT value.

[0024] (Mechanism for maintaining the hydrophilicity of the toilet bowl) It is known that ozone, hydrogen peroxide, and free chlorine have the ability to oxidize amino acid residues such as cysteine ​​and methionine, which are components of proteins. Hydrophobic proteins adsorbed to the surface of the toilet bowl are oxidized by discharging modified water. Oxidation causes the hydrophobic proteins to become hydrophilic, which is thought to make them easily removed by modified water or running water. As a result, the surface of the toilet bowl is exposed so that it can come into contact with water, allowing it to continue to exhibit its original hydrophilicity.

[0025] In addition, in the second aspect of the present invention, by incorporating hydrophilic organic functional groups into the surface of the bowl surface of the toilet, the limescale removal performance can be improved; in other words, even if limescale formed by combining with (a small amount of) protein remaining on the surface even after contact with the modified water adheres to the surface, it can be removed by cleaning, and it is believed that the original hydrophilicity can be maintained for a long period of time.

[0026] Configuration of the Device for Discharging Modified Water As shown in FIG. 1, the device 1 for discharging modified water of the present invention comprises a generating unit 2 that generates modified water, and a discharging unit 3 that discharges the generated modified water onto the bowl surface 4 of the toilet.

[0027] (Generation Unit) The generation unit 2 is equipped with a mechanism for generating reformed water. As described below, reformed water is water containing at least one active ingredient selected from the group consisting of ozone, hydrogen peroxide, and free chlorine. The reformed water is generated, for example, by any of the following methods: (1) electrolysis of water, (2) mixing of water with gas, or (3) addition of chemicals. In the present invention, the water is preferably tap water. Tap water refers to water supplied to buildings such as homes, and is preferably water that has been subjected to a sterilization treatment such as chlorination at a water purification plant. "Tap water" includes not only clean water but also grey water. Grey water is preferably water that has been subjected to a sterilization treatment such as chlorination. In the present invention, it is preferable to generate reformed water by subjecting tap water directly to, for example, electrolysis.

[0028] (1) Water electrolysis: Water is electrolyzed (also simply referred to as electrolysis) to produce reformed water. This method is advantageous in that reformed water can be produced by electrolyzing water while it is flowing through the system, and can be immediately discharged, eliminating the need for waiting time before discharge and limiting the amount of reformed water produced during continuous use. - Configuration of the electrolysis system's generator: For example, it may include an electrode pair and, optionally, a means for supplying electrolyte to the electrode pair. Suitable materials for the electrode pair include, for example, an electrode having a catalyst layer made of platinum, iridium oxide, rhodium oxide, or tantalum oxide on a titanium electrode substrate, as disclosed in Japanese Patent No. 5886052; a boron-doped conductive diamond electrode, as disclosed in Japanese Patent No. 5710691; and an electrode containing tin oxide as the main component with tantalum oxide and niobium oxide added, as disclosed in Japanese Patent Publication No. 2023-144335. When producing free chlorine water by electrolysis, it is preferable to supply chlorine ions to the electrode. The chloride ions are preferably supplied using a water-soluble chloride, and when the chloride is used, it may be supplied in the form of a solid or an aqueous solution.

[0029] (2) Mixing water and gas: Air is activated to generate gas containing active ingredients, and the generated gas is dissolved in water to generate modified water. This method is suitable for use when the modified water is ozone water, because ozone gas, which has low solubility in water, can be efficiently dispersed in the water. Furthermore, when the ozone gas dispersed in the modified water is in the form of fine bubbles with a diameter of 100 μm or less, this method is more preferable because it can extend the time until the ozone dissipates into the atmosphere.

[0030] Methods for mixing water and gas include the pressurized dissolution method, Venturi method, shear method, etc., as shown in JP 2011-173038 A. For example, in the shear method, water in which coarse gas of about several millimeters in diameter is dispersed is passed through a mesh with minute openings of about several millimeters to several micrometers in diameter, whereby the gas is sheared by the mesh, thereby generating fine bubbles.

[0031] (3) Addition of chemicals: High-concentration chemicals are dissolved in water to produce modified water. This method requires the user to replenish the chemicals, but it simplifies the device configuration because it does not require electrolysis or gas generation mechanisms.

[0032] (Discharge Unit) The discharge unit 3 is equipped with a mechanism for discharging the modified water onto the bowl surface of the toilet. Such mechanisms include flow discharge, shower discharge, and spray (mist) discharge, and gas-liquid mixed discharge may be used to reduce the amount of modified water used. The discharge unit 3 may also have the function of discharging tap water. Discharge of the modified water to an area where hydrophobicity should be suppressed is achieved by discharging the modified water from the discharge unit 3. An example of a mechanism equipped in the discharge unit 3 is a nozzle. An annular groove, a guide plate, or the like may be provided inside the nozzle. With such a structure, the water inside the nozzle is made into a swirling flow, which allows the modified water to be discharged as a mist.

[0033] The discharge unit 3 may include a pipe 7 that supplies the modified water generated in the generation unit 2 to the discharge unit 3. Alternatively, the discharge unit 3 may be directly connected to the generation unit. The discharge unit 3 may also have the function of discharging tap water.

[0034] In the case of spray (mist) discharge, for example, an atomizing device can be provided in the discharge section 3, and the particle size of the mist can be reduced so that the modified water can be distributed over a wide area to the bowl surface 4 by diffusion, etc. In the case of gas-liquid mixed discharge, for example, an air bubble mixing device can be provided upstream of the discharge section 3.

[0035] When discharging reforming water containing ozone, it is preferable not to make the particle size of the mist too small in order to suppress excessive evaporation of ozone from the reforming water. The particle size of the mist is generally represented by the Sauter mean particle size expressed by the following formula: Sauter mean particle size (D32) [μm] = Σnd ３ / Σnd ２ n: number of particles d: particle diameter [μm]

[0036] Laser diffraction can be used as one method for measuring the particle size of mist. FIG. 13 is a perspective view showing an example of a method for measuring the particle size of mist using laser diffraction. In the embodiment shown in FIG. 13, a particle size measuring device 20 has a light-emitting unit 21 and a light-receiving unit 22. The light-receiving unit 22 is configured to receive the laser emitted by the light-emitting unit 21. During measurement, the laser from the light-emitting unit 21 is irradiated onto the mist M sprayed from the water discharge unit 3, and the diffracted and scattered light is received by the light-receiving unit 22. Specifically, the laser light emitted from the light-emitting unit 21 is scattered by the particles of the mist M, and the scattered light is detected by the light-receiving unit 22. With the laser transmittance in the range of 60% to 90%, the distribution of the scattered light is measured via the light-receiving unit 22. This detects a light intensity distribution pattern, and the particle size distribution of the mist particles is calculated based on that pattern. For example, an Aerotrac LDSA-3500A manufactured by Microtrac Bell Corporation can be used as the particle size measuring device 20. As a setting condition of the device, the position for measuring the particle diameter is set, for example, at a position 10 cm away from the discharge part 3. The particle diameter can be adjusted by the opening diameter and flow rate of the water discharge part 3 (for example, a spray nozzle).

[0037] In the present invention, when the modified water is ozone water, the particle size of the ozone water mist is preferably at least 100 μm, more preferably 300 μm, and even more preferably 1000 μm or more, as Sauter mean particle size calculated by the measurement method using the laser diffraction method, with a preferred upper limit of 5000 μm or less. With this particle size, the ozone contained in the modified water of the present invention can be reliably discharged onto the bowl surface 4, preferably onto a portion where hydrophobicity is desired to be suppressed, and damage to components and human bodies caused by vaporized ozone can be suppressed.

[0038] When spraying modified water containing hydrogen peroxide or modified water containing free chlorine, in order to spray the modified water over a wide surface with a small amount of liquid, it is preferable that the particle diameter of the mist of hydrogen peroxide water or free chlorine water be at least 20 μm or more and 100 μm or less in terms of Sauter mean particle diameter calculated by the measurement method using the above-mentioned laser diffraction method.

[0039] Modified Water (Types of Modified Water) In the present invention, the modified water contains, as an active ingredient, a component having oxidizing power. These components have the ability to decompose and remove hydrophobic urine-derived proteins that adhere to the bowl surface of the toilet, maintain the hydrophilicity of the bowl surface, reduce fungi and mold, or inactivate viruses. In one embodiment of the present invention, the modified water is oxidized by ozone (O ３ In the present invention, the term "free chlorine" refers to an aqueous solution containing at least one active ingredient selected from the group consisting of hypochlorous acid (HClO) and hypochlorite ions (ClO). － ) combination (mixture).

[0040] (Oxidation-reduction potential of active ingredients in reformed water) The strength of the oxidizing power of the active ingredients contained in the reformed water is determined by the oxidation-reduction potential of the active ingredients contained in the reformed water. For example, according to the Electrochemistry Handbook (6th edition, Maruzen), the oxidation-reduction potential of hypochlorous acid (HClO), which is a type of free chlorine, is 1.63, and ingredients with stronger oxidizing power than hypochlorous acid include ozone (oxidation-reduction potential 2.06) and hydrogen peroxide (oxidation-reduction potential 1.76).

[0041] (Definition and Measurement Method of Modified Water Concentration) The method for quantifying the ozone concentration in water is the indigo method, as defined in JIS B 9946:2019, in which the concentration of indigo decolorized by reaction with ozone is measured using a spectrophotometer and the ozone concentration is calculated from the decrease in absorbance. The method for quantifying the free chlorine concentration in water is the DPD colorimetric method, as defined in JIS K 0400-33-10:1999, in which free chlorine reacts with DPD (N,N-diethyl-p-phenylenediamine) to produce a red color. The method for quantifying hydrogen peroxide in water is the oxidation-reduction titration method, as defined in the Japanese Pharmacopoeia, in which hydrogen peroxide is reacted with potassium permanganate and the point at which a sudden change in potential difference occurs is detected as the equivalence point. Alternatively, a quantification method based on the color reaction of a dye (Xylenol Orange) accompanying the oxidation of iron ions by hydrogen peroxide may be used.

[0042] (Concentration of active ingredient) The concentration of the active ingredient in the modified water is preferably in the range of 0.05 ppm to 5 ppm for ozone, 0.05 ppm to 50 ppm for hydrogen peroxide, and 0.1 ppm to 5 ppm for free chlorine.

[0043] More preferred concentrations of the active ingredients are 0.3 ppm to 3 ppm for ozone, 0.05 ppm to 10 ppm for hydrogen peroxide, and 0.1 ppm to 5 ppm for free chlorine.

[0044] Even more preferred concentrations of the active ingredients are: ozone in the range of 0.5 ppm to 1.5 ppm; hydrogen peroxide in the range of 0.5 ppm to 3 ppm; and free chlorine in the range of 1 ppm to 3 ppm.

[0045] If the concentration is within the above range, it is possible to prevent the reduction of the active ingredient due to scattering into the atmosphere, etc., and to suppress damage to the human body and deterioration of equipment.

[0046] Discharge of Reformed Water The reformed water is discharged for a predetermined time from the water discharge portion 3 onto the bowl surface 4. At this time, it is preferable that the reformed water is at room temperature.

[0047] (Modified Water Discharge Time) The time for discharging the modified water at one time is preferably between 1 and 180 seconds, more preferably between 3 and 60 seconds, and even more preferably between 3 and 20 seconds. If the discharge time is too short, the surface hydrophobicized by the protein becomes hydrophilic, and the discharge ends before the modified water can spread evenly, which may prevent the surface from being uniformly hydrophilized. Furthermore, if the discharge time is too long, the waiting time for the toilet user to excrete becomes long if the modified water is discharged after the toilet has started to be used, and if the modified water is discharged after the toilet has finished being used, the waiting time for the next user becomes too long, which is undesirable.

[0048] (Means and methods for realizing a discharge time in the embodiment shown in FIG. 1) In the embodiment shown in FIG. 1, a container such as a tank that can store a fixed amount of water is provided in the generation unit 2, and after a fixed amount of reformed water is generated, it is discharged from the discharge unit 3 using gravity or other driving force, thereby realizing a fixed discharge time. Furthermore, the discharge time may be adjusted by means such as narrowing the diameter of the flow path in the discharge unit 3. As another means, when the reformed water is discharged manually, a movable part such as a piston or pump is provided in the generation unit 2 or the discharge unit 3, and a damper mechanism such as a dashpot is provided in this movable part, thereby making it possible to realize a discharge time within a fixed range regardless of the amount of force applied when manually.

[0049] CT value: product of concentration of active ingredient in modified water and discharge time of modified water In the present invention, the hydrophobicity inhibiting effect of modified water, i.e., the hydrophilicity maintaining effect, can be obtained by controlling the product of the concentration of active ingredient contained in the modified water and the time for which the modified water is discharged onto the bowl surface of the toilet (the area where it is desired to maintain hydrophilicity), i.e., the time for which the modified water is in contact with the bowl surface, i.e., the CT value (unit: ppm-seconds).

[0050] In the present invention, to maintain the hydrophilicity of the toilet bowl surface, modified water is discharged under the following conditions A, B, or C: A: The modified water is ozone water and is discharged with a CT value of 2 ppm·sec or more and 100 ppm·sec or less; B: The modified water is hydrogen peroxide water and is discharged with a CT value of 5 ppm·sec or more and less than 1000 ppm·sec; or C: The modified water is free chlorine water and is discharged with a CT value of 20 ppm·sec or more and 300 ppm·sec or less. Under these conditions, the modified water decomposes urinary proteins, suppressing their adhesion to the toilet bowl surface and maintaining the hydrophilicity of the bowl surface, while also suppressing damage to equipment, injury to the human body, and unpleasant odors due to the volatilization of modified water components. In the present invention, the mode in which modified water is discharged under the above conditions A, B, or C is referred to as the "hydrophilization mode."

[0051] As previously explained, proteins contained in urine adhering to the surface of a toilet bowl become hydrophobic upon drying, impairing the inherent hydrophilicity of the sanitary ware. As a result, not only does this reduce the ability to clean waste, but it also makes the surface more susceptible to bacterial adhesion and serves as a breeding ground for bacteria. Furthermore, even if free chlorine water is modified with a sufficient concentration for sterilization purposes, it is insufficient for preventing hydrophobicity of hydrophilic surfaces unless it is dispensed for an appropriate length of time and frequency. For example, Patent Document 1 indicates that a CT value of 10 ppm·sec is required for free chlorine water to be effective against microorganisms when heated to 40°C or higher. However, such a CT value is difficult to fully prevent hydrophobicity of hydrophilic surfaces. On the other hand, hydrogen peroxide water indicates that a CT value of 10,000 ppm·sec is required when heated to 40°C or higher to achieve sterilization effects. However, dispensing high-concentration hydrogen peroxide water, such as 1,000 ppm or higher, in wet areas poses concerns about human health risks, resin degradation, and electrode load, as well as the need for heating equipment. Furthermore, conventional modified water, such as those described in Patent Documents 1 to 3, which are expected to have a disinfecting effect, is insufficient to disinfect the interior of feces attached to the surface of a toilet bowl, because its active ingredients react with organic matter and are consumed. Feces contain bacteria and viruses that can cause infectious diseases harmful to the human body, and these pose a higher risk of infection than environmentally-derived bacteria and molds that grow on the surface of a toilet bowl. The device of the present invention, which discharges modified water at the specific CT value described above, not only suppresses the hydrophobicity of the hydrophilic bowl surface of the toilet bowl, maintaining the hydrophilicity, but also minimizes the amount of feces remaining on the bowl surface, further improving hygiene. Furthermore, it can also effectively remove various stains that arise secondary to the hydrophobicity of the bowl surface.

[0052] Conventional modified waters such as those described in Patent Documents 1 to 3 are primarily intended to disinfect the interior of a toilet bowl. However, the present inventors discovered that discharging modified water with oxidizing power can decompose and remove hydrophobic proteins adhering to the surface of a toilet bowl, thereby maintaining the hydrophilicity of the sanitary ware. Furthermore, they confirmed that the more oxidizing components the modified water contains, the more effective the maintenance of hydrophilicity becomes, and that the longer the modified water is in contact with the surface of the component for which hydrophilicity is desired to be maintained, the greater the effect. They confirmed that the optimal ranges of the components, their concentrations, and contact times of the modified water for maintaining the hydrophilicity of the toilet bowl surface are different from those of modified waters conventionally used in the hope of disinfecting the surface.

[0053] In the present invention, preferred CT values ​​are in the range of 2 ppm-seconds to 100 ppm-seconds when the modified water is ozone water, in the range of 5 ppm-seconds to 500 ppm-seconds when the modified water is hydrogen peroxide water, and in the range of 20 ppm-seconds to 300 ppm-seconds when the modified water is free chlorine water.

[0054] More preferred CT values ​​are in the range of 2 ppm·sec to 100 ppm·sec when the modified water is ozone water, in the range of 5 ppm·sec to 100 ppm·sec when the modified water is hydrogen peroxide water, and in the range of 20 ppm·sec to 300 ppm·sec when the modified water is free chlorine water.

[0055] Even more preferable CT values ​​are in the range of 5 ppm·sec to 50 ppm·sec when the modified water is ozone water, in the range of 5 ppm·sec to 50 ppm·sec when the modified water is hydrogen peroxide water, and in the range of 30 ppm·sec to 100 ppm·sec when the modified water is free chlorine water.

[0056] Particularly preferred CT values ​​are in the range of 10 ppm·sec to 20 ppm·sec when the modified water is ozone water, in the range of 10 ppm·sec to 20 ppm·sec when the modified water is hydrogen peroxide water, and in the range of 40 ppm·sec to 60 ppm·sec when the modified water is free chlorine water.

[0057] Within the above range, even if urine-derived proteins have firmly adhered to the bowl surface of the toilet due to drying, they can be sufficiently decomposed and removed, and the bowl surface can be restored to its hydrophilicity.

[0058] Preferred Embodiment of Device for Discharging Reformed Water In a preferred embodiment of the present invention, the device for discharging reformed water further includes a detection unit 8 and a control unit 9, as shown in FIG. 2. The detection unit 8 detects, for example, the approach of a human body or whether the human body is sitting or leaving its seat, or the flushing of a toilet. The control unit 9 controls, for example, the startup of the reformed water generating device 1, the electrolysis of water, the discharge of reformed water, etc. In another preferred embodiment, the device for discharging reformed water further includes a signal receiving unit 11 and a control unit 9, as shown in FIG. 3. The signal receiving unit 11 receives a signal from the detection unit 8, which is configured separately from the device for discharging reformed water, via the signal transmitting unit 11, and transmits the signal to the control unit 9. In other words, the detection unit 8 may be incorporated inside the device for discharging reformed water 1, or may be incorporated in an external device.

[0059] (Detection Unit) The detection unit 8 may be a mechanism for detecting the approach of a human body or whether a person has sat down or left the seat, or a mechanism for detecting the flushing of the toilet bowl, or it may include both. For example, a sensor capable of detecting human body movement can be suitably used as the detection unit 8. In this case, the detection unit 8 detects when a person has left the toilet, automatically detects the start or end of use of the toilet, and sends a signal to the control unit 9. Suitable sensors for detecting human body movement include a sensor that detects whether a user has sat down on or left the toilet seat, specifically, a seat sensor that detects whether a user has sat down, a seat-away sensor that detects whether a user has left the seat, a (single) sensor that detects both sitting and leaving the seat, or a combination of a seat sensor and a seat-away sensor (each sensor is separate). Alternatively, the detection may be triggered by an operation of the device 1 for discharging reformed water, which is operated by the control unit 9, in conjunction with an operation related to the user's end of use of the device 1 for discharging reformed water. Here, an action associated with the user's termination of use of the device 1 that dispenses modified water includes, for example, a toilet flushing action. In this case, it is desirable that the toilet flushing be performed without touching it. In the present invention, examples of sensors that can be suitably used as the detection unit include a load sensor, an infrared sensor, a microwave sensor, a capacitance sensor, and a heat ray sensor.

[0060] (Signal Receiving Unit) The signal receiving unit 11 is a mechanism that receives a signal detected by the detecting unit 8 and transmits it to the control unit 9, and wirelessly connects the detecting unit 8 and the control unit 9 when the detecting unit 8 and the control unit 9 are not physically connected by an electronic circuit or the like. An example of the signal receiving unit 11 is an infrared light receiving module. The light receiving module will be described using a warm water washing toilet seat as an example.

[0061] A warm water washing toilet seat consists of a warm water washing toilet seat main body and a remote control. The warm water washing toilet seat main body has a built-in modified water discharge device and an infrared receiving module. The remote control has a built-in detection unit and an infrared emitting module. The detection unit can be a heat sensor that detects heat rays emitted by the user. The infrared emitting module and infrared receiving module are paired modules used to send and receive signals. Note that while the heat sensor detects infrared rays, it is configured so that it does not interfere with the infrared emitting / receiving module. By wirelessly connecting the remote control to the warm water washing toilet seat, the modified water discharge device installed in the warm water washing toilet seat can be activated by the user's actions detected by the remote control. Another example is a configuration in which an indoor motion sensor light equipped with a detection unit is wirelessly connected to the warm water washing toilet seat main body, and modified water is discharged when a user approaches.

[0062] (Controller) The controller 9 is, for example, a mechanism that controls the generation of reformed water with an active ingredient concentration within a predetermined range, and a mechanism that controls the discharge of reformed water at a specific timing based on a signal sent from the detector 8. The controller 9 may also have a function to control the concentration of the active ingredient by controlling both or either the voltage and the current applied to the electrodes that generate the electrolytic reformed water. The controller 9 starts or stops the generator 2 based on the toilet bowl usage state detected by the detector 8. If the generator 2 uses an electrolytic system, the discharge time of the reformed water may be controlled by setting the time for generating voltage to the generator 2 within a predetermined range, or, if the device 1 that discharges the reformed water is equipped with a valve 6, the discharge time may be controlled by the opening and closing time of the valve 6. The controller 9 may also control the discharge of tap water to clean the bowl surface 4.

[0063] The control unit 9 includes electronic components such as a programmable logic controller (PLC) and a microcomputer, and these components are connected to the detection unit 8 via wire or wirelessly so as to receive signals. The control unit 9 is also connected to the generation unit 2 or the valve 6 provided in the device 1 that discharges the reformed water, and controls the frequency, timing, and discharge time of the generation and discharge of the reformed water in accordance with the signal obtained from the detection unit 8 so that they fall within predetermined ranges.

[0064] (Control of Reformed Water Discharge) According to a preferred embodiment of the present invention, reformed water is discharged onto the bowl surface at a frequency of at least once every 10 uses of the toilet. Specifically, the control unit 9 receives signals from the detection unit 8 indicating a user's approach or sitting, and counts the number of uses by regarding the number of times this signal is received as the number of times the toilet has been used. By discharging reformed water when the number of uses reaches a predetermined number, the discharge can be controlled according to the number of times the toilet has been used.

[0065] (Using the Toilet) In the present invention, using the toilet refers to the act of approaching the toilet to leaving it. Use is considered to begin when the user sits on the toilet or stands still in front of the toilet without walking, and use is considered to end when the user stands up or leaves the toilet after defecating or urinating. Use of the toilet can be detected by the detection unit 8.

[0066] (Preferred Frequency of Discharging Modified Water) The hydrophobicity of the hydrophilic bowl surface of a toilet bowl increases the more frequently urine comes into contact with the bowl surface. In the field test described below, the static contact angle of water reached 100° after 10 uses, and the contact angle did not increase with subsequent contact with urine. Therefore, the frequency of discharging modified water in the present invention is preferably at least once every 10 uses of the toilet. This allows the bowl surface to be kept constantly hydrophilic. More preferably, it is at least three times every 10 uses of the toilet, and even more preferably, every time the toilet is used, i.e., every time. The upper limit of the frequency of discharging modified water in the present invention is preferably no more than 10 times every 10 uses of the toilet.

[0067] Because the hydrophobicity of the toilet bowl occurs due to the adhesion of proteins in urine, the degree of hydrophobicity increases with the number of times the toilet bowl is used. This phenomenon differs from the phenomenon in which microbial soiling derived from tap water grows over time. Therefore, the inventors have discovered that, in order to prevent the hydrophobicity of the toilet bowl, it is more effective to discharge modified water in accordance with the number of times the toilet bowl is used, rather than discharging modified water in accordance with the passage of time.

[0068] (CT Value of Modified Water Discharged Each Time) In the present invention, when modified water is discharged each time the toilet is used, there is a high possibility that the proteins will be in a state before they dry out, and therefore a small CT value will enable efficient removal, and it is preferable to discharge modified water with the following CT values, as this can reduce equipment deterioration and injury to the human body: If the modified water is ozone water, the range is from 2 ppm-seconds to 10 ppm-seconds; If the modified water is hydrogen peroxide water, the range is from 5 ppm-seconds to 10 ppm-seconds; If the modified water is free chlorine water, the range is from 20 ppm-seconds to 40 ppm-seconds.

[0069] (Preferred Timing of Discharge of Modified Water) In the present invention, the discharge of modified water is preferably carried out after the start and / or end of toilet use. Discharge of modified water after the start of toilet use can restore the toilet bowl surface to its hydrophilic state even if hydrophobic dust and dirt from the atmosphere, in addition to urine-derived proteins, has accumulated on the toilet bowl. To ensure that discharge of modified water can begin before the user defecates, the modified water is preferably discharged onto the bowl surface within 3 seconds of the start of toilet use, more preferably within 1 second. Furthermore, the discharge of modified water is preferably performed when the user sits down, so that dust and dirt do not accumulate on the toilet bowl after discharge. Alternatively, discharging modified water after the end of toilet use can efficiently remove urine-derived proteins before they dry and become more firmly attached. Even on hydrophilic surfaces, a water film can only be maintained for about 10 seconds on inclined surfaces such as the bowl surface of a toilet. Therefore, the modified water is preferably discharged onto the bowl surface within 10 seconds of the end of toilet use, more preferably within 5 seconds.

[0070] (Sterilization Mode) In addition to the above-described mode for hydrophilizing the bowl surface of the toilet bowl ("hydrophilization mode"), the device for discharging modified water of the present invention preferably also has a mode for sterilizing bacteria and the like adhering to the bowl surface or the discharge portion (hereinafter referred to as "sterilization mode"). The sterilization mode preferably controls one or more of the active ingredients, CT value, discharge form, discharge frequency, and discharge timing of the modified water under conditions different from those in the hydrophilization mode. When the hydrophilization mode and sterilization mode are used together, it is more preferable that the sterilization mode has different conditions for the discharge frequency and / or discharge timing than those in the hydrophilization mode.

[0071] Active Ingredients: More specifically, the sterilization mode is a mode in which modified water is discharged with the aim of reducing or inactivating bacteria, fungi, and viruses present in the toilet bowl environment, such as bacteria present in the water environment, such as Methylobacterium, and fecal-derived bacteria, such as Escherichia coli. Therefore, in the sterilization mode, the active ingredient of the modified water can be suitably one or more selected from the group consisting of silver ions, copper ions, and cationic surfactants, in addition to the above-mentioned ozone, hydrogen peroxide, and free chlorine. A more preferred active ingredient is ozone, hydrogen peroxide, or free chlorine, which are the same active ingredients as those used in the hydrophilization mode, because this simplifies the device for discharging the modified water. An even more preferred active ingredient is a mixture of ozone and free chlorine. Different active ingredients of the modified water may be used depending on the mode, such as discharging hydrogen peroxide, which has low volatility, in the hydrophilization mode, and discharging ozone water, which does not produce resistant bacteria, in the sterilization mode.

[0072] CT value: When ozone or hydrogen peroxide is used as the active ingredient in the sterilization mode, the CT value is preferably larger than that in the hydrophilization mode. Also, when free chlorine is used as the active ingredient in the sterilization mode, the CT value can be smaller than that in the hydrophilization mode. Therefore, suitable ranges of CT values ​​are: more than 100 ppm-second and 1800 ppm-second or less when the modified water is ozone water; 1000 ppm-second or more and 50000 ppm-second or less when the modified water is hydrogen peroxide water; and 5 ppm-second or more and 20 ppm-second or less when the modified water is free chlorine water; more preferably: 150 ppm-second or more and 1800 ppm-second or less when the modified water is ozone water; 1000 ppm-second or more and 50000 ppm-second or less when the modified water is hydrogen peroxide water; and 5 ppm-second or more and 20 ppm-second or less when the modified water is free chlorine water; and even more preferably: 150 ppm-second or more and 300 ppm-second or less when the modified water is ozone water; If the modified water is hydrogen peroxide water, the CT value should be between 10,000 ppm / sec and 30,000 ppm / sec, and if the modified water is free chlorine water, the CT value should be between 10 ppm / sec and 20 ppm / sec. By keeping the CT value within the above range, the bowl surface can be effectively sterilized.

[0073] Discharge Pattern: In the hydrophilic mode, the modified water is sprayed to cover a wide area of ​​the bowl surface of the toilet bowl, while in the sterilization mode, the modified water is showered to selectively cover the boundary between the accumulated water and the bowl surface, where ring stains are likely to occur. In the hydrophilic mode, the modified water is preferably discharged so that it contacts 50% to 100% of the bowl surface and 90% to 100% of the boundary between the accumulated water and the bowl surface. In the sterilization mode, the modified water is preferably discharged so that it contacts 20% to 50% of the bowl surface and 90% to 100% of the boundary between the accumulated water and the bowl surface. Furthermore, when a user urinates while seated, urine comes into contact with the front of the bowl surface for a long period of time, while when a user urinates while standing facing the toilet, urine comes into contact with the rear of the bowl surface for a long period of time. Therefore, in the hydrophilic mode, the modified water is preferably discharged to cover the front area of ​​the bowl surface, and more preferably both the front and rear areas. On the other hand, because fungal stains tend to occur preferentially at the boundary between the pooled water and the bowl surface, it is preferable that modified water be discharged at this boundary in the sterilization mode. By discharging water in this manner, the bowl surface can be kept hydrophilic in the hydrophilization mode, and in the sterilization mode, the active ingredient can be efficiently brought into contact with the boundary and other areas where microorganisms and stains are likely to occur, thereby enabling efficient sterilization.

[0074] - Discharge Frequency Because the bacteria targeted by the modified water in the sterilization mode multiply so that their numbers double within a few tens of minutes to a few hours, it is preferable that the modified water be discharged at least once every few hours, even when the toilet is not in use. Furthermore, the sterilization mode and the hydrophilization mode may be selectively used based on the frequency of toilet use over time. As an example of selectively using the sterilization mode and the hydrophilization mode depending on the time of day, modified water may be discharged in the sterilization mode during times of low toilet use, such as at night, when bacterial growth takes precedence over hydrophobization of the toilet bowl surface, and modified water may be discharged in the hydrophilization mode during times of high toilet use, such as during the day, when hydrophobization of the toilet bowl takes precedence.

[0075] Specifically, it is preferable that: - when the toilet is used 10 times or more per hour, modified water is ejected in hydrophilic mode at least three times per 10 uses and in sterilization mode at most seven times per 10 uses; - when the toilet is used 3 to less than 10 times per hour, modified water is ejected in hydrophilic mode at least two times per 10 uses and in sterilization mode at most eight times per 10 uses; - when the toilet is used less than three times per hour, modified water is ejected in hydrophilic mode at least once per 10 uses and in sterilization mode at most nine times per 10 uses.

[0076] In addition, the toilet usage status for one day may be stored, and the sterilization mode may be controlled to be performed during times when the toilet is least frequently used.

[0077] Discharge timing: Different modes may be used after the start and end of toilet use. Also, it is not desirable to continuously discharge modified water in the hydrophilic mode and modified water in the sterilization mode after the start and end of toilet use, as this would lengthen the total time the modified water is discharged, thereby lengthening the user's waiting time.

[0078] Preferred modes of timing of discharge include the following: Mode (1): Discharge modified water in hydrophilic mode after the start of toilet use, and discharge modified water in sterilization mode after use has ended. By discharging modified water in hydrophilic mode after the start of toilet use, the modified water remains on the hydrophilized bowl surface, allowing the stool to slide smoothly. Mode (2): Discharge in both hydrophilic mode and sterilization mode is performed after the end of toilet use. However, discharge in hydrophilic mode and discharge in sterilization mode are not performed consecutively after the end of one toilet use. In other words, mode (2) combines a pattern in which discharge in hydrophilic mode is performed after the end of toilet use, and a pattern in which discharge in sterilization mode is performed after the end of toilet use.

[0079] It is preferable to select the configurations (1) and (2) appropriately depending on the time period or the frequency of use of the toilet. For example, when discharging the reformed water after use of the toilet in the sterilization mode, it is preferable to discharge the reformed water within 10 seconds after use of the toilet. In this case, the waiting time until the next use of the toilet can be reduced.

[0080] The present invention also relates to a toilet apparatus comprising at least the above-described device for discharging modified water and a toilet having a hydrophilic bowl surface, preferably a bowl surface containing hydrophilic organic functional groups on its surface. Specifically, the toilet apparatus of the present invention comprises a toilet having a hydrophilic bowl surface, preferably a bowl surface containing hydrophilic organic functional groups on its surface, a toilet seat, a tank, and a device for discharging modified water connected to one or more of them, at least including a toilet having a hydrophilic bowl surface, preferably a bowl surface containing hydrophilic organic functional groups on its surface, and the device for discharging modified water. Figure 4 is a schematic diagram showing an example of the toilet apparatus of the present invention. For ease of explanation, the schematic diagram of a Western-style seated toilet in Figure 4 is a cross-sectional view.

[0081] (Toilet Bowl) In the present invention, the toilet bowl is a flush toilet bowl and has a bowl surface. The toilet bowl preferably further has a trap part, and more preferably further has a flush part such as a tank.

[0082] (Bowl surface) The bowl surface 4 refers to the area inside the toilet bowl that is not constantly in contact with water, and if the toilet is equipped with a trap, it is the area above the accumulated water. The bowl surface 4 receives urination and defecation, and corresponds to the area where hydrophobicity should be suppressed. The surface of the bowl surface 4 is hydrophilic to improve cleanability. It is preferable that a surface layer is formed on the surface of the bowl surface 4, specifically by a glaze or coating, as described below.

[0083] Hydrophilicity In the present invention, the surface of bowl surface 4 is hydrophilic. The hydrophilicity is preferably such that the static contact angle of water is 30° or less, more preferably 20° or less. The static contact angle of water can be measured using a contact angle meter (model number: DMs-401, manufactured by Kyowa Interface Science Co., Ltd.). 2 μl of ion-exchanged water is dropped as a droplet, and the contact angle of the droplet is measured after 5 seconds.

[0084] Glaze: In the present invention, a preferred material that can be applied to the bowl surface to make it hydrophilic is glaze. This glaze is a non-absorbent glassy material, such as a film made by melting and densifying a mixture of fine powders of crushed silica, alumina, zircon, etc.

[0085] Surface In the present invention, a more preferred material that can be applied to the bowl surface to make the surface hydrophilic is a hydrophilic organic functional group. That is, in the second embodiment of the present invention, the hydrophilic bowl surface of the first embodiment is a bowl surface containing a hydrophilic organic functional group on its surface. A preferred method for incorporating a hydrophilic organic functional group into the surface of the bowl surface is to form a surface layer by coating. The composition used to form the surface layer can be either one containing a monomer having a hydrophilic organic functional group or one containing a polymer obtained by polymerizing a monomer having a hydrophilic organic functional group. The surface layer preferably contains a hydrophilic organic functional group on its surface, and more preferably, the hydrophilic organic functional group is present more on the surface side than in the interior of the surface layer. Specific examples include a coating film in which a polyfunctional (meth)acrylamide monomer serving as a skeleton and a hydrophilic monomer are cured by a polymerization reaction, as disclosed in WO2017 / 018146, and a coating film in which a hydrophilic polymer having a silane coupling group at the end or in the side chain is chemically bonded to a substrate via a metalloxane bond, as disclosed in JP2008-239949A.

[0086] Hydrophilic Organic Functional Group In the second aspect of the present invention, the hydrophilic organic functional group (hereinafter, sometimes simply referred to as "hydrophilic group") can be divided into ionic and nonionic hydrophilic groups, and the ionic hydrophilic group can be further divided into cationic, anionic, and zwitterionic hydrophilic groups. Examples of cationic hydrophilic groups include quaternary ammonium (N ＋ ), sulfonium (S ＋ ), phosphonium (P ＋ Examples of anionic hydrophilic groups include carboxylic acid and its salts (—COO － ), phosphonic acid or its salt (—PO ４ ２－ , -HPO ４ － ), sulfonic acid or its salt (—SO ３ － In the second aspect of the present invention, the amphoteric hydrophilic group means a hydrophilic group having at least one cationic hydrophilic group and one anionic hydrophilic group in the same molecule, and among them, a quaternary ammonium salt is included as a cation and -SO 4 is included as an anion in the molecule. ３ － or a sulfobetaine containing a quaternary ammonium cation in the molecule and -PO as an anion ４ ２－ The phosphobetaine containing the compound is preferably a phosphobetaine containing a quaternary ammonium cation in the molecule and an -SO ３ － Sulfobetaines containing the following are more preferred. Examples of nonionic hydrophilic groups include a hydroxyl group (-OH), an ether bond (-O-), an ester bond (-COO-), a urea bond (-NH-CO-NH-), a urethane bond (-NH-COO-), and an amide bond (-NH-CO-). In the second aspect of the present invention, compounds having cationic, anionic, zwitterionic, and nonionic hydrophilic groups can be mixed in any ratio. In order to enhance the ability to remove limescale, it is preferable for the compound to contain at least an anionic or nonionic functional group.

[0087] In the second embodiment of the present invention, examples of the monomer having a hydrophilic organic functional group include trimethyl-2-methacryloyloxyethyl ammonium chloride, potassium 3-(methacryloyloxy)propanesulfonate, 2-(methacryloyloxy)ethanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, potassium 3-(acryloyloxy)propane-1-sulfonate, potassium 2-(acryloyloxy)ethane-1-sulfonate, sodium p-styrenesulfonate, 3-[[2-(acryloyloxy)ethyl]dimethylammonium chloride, and the like. 2-[[2-(methacryloyloxy)ethyl]dimethylammonio]propane-1-sulfonic acid, 3-[[2-(methacryloyloxy)ethyl]dimethylammonio]propane-1-sulfonic acid, [3-(methacryloylamino)propyl]dimethyl(3-sulfobutyl)ammonium hydroxide, 4-[(3-methacrylamidopropyl)dimethylammonio]butane-1-sulfonic acid, 3-[[2-(methacryloyloxy)ethyl]dimethylammonio]propionate, 2-[[2-(methacryloyloxy)ethyl]dimethylammonio]acetic acid, 2-(methacryloyloxy)ethyl 2-(trimethylammonium phosphate Methylammonio)ethyl], 4-[[2-(methacryloyloxy)ethyl]dimethylammonio]butane-1-sulfonic acid, 3-[(3-acrylamidopropyl)dimethylammonio]propanoate, 3-[(3-acrylamidopropyl)dimethylammonio]propane-1-sulfonic acid, 3-[(3-methacrylamidopropyl)dimethylammonio]propane-1-sulfonic acid, 2-aminoethylsulfonic acid sodium salt, 2-aminoethylsulfonate potassium, 4-aminobenzenesulfonic acid sodium salt, 2-hydroxyethylsulfonic acid Examples include sodium, sodium 3-mercapto-1-propanesulfonate, sodium 2-glycidylethylsulfonate, sodium aminosulfonate, potassium aminosulfonate, aminomethanesulfonic acid, 3-aminopropanesulfonic acid, 2-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid, 1-amino-2-naphthol-4-sulfonic acid, 6-amino-4-hydroxy-2-naphthalenesulfonic acid, sodium hydroxymethanesulfonate, and 4-hydroxy-1-butanesulfonic acid, and at least one of these can be used.

[0088] Fig. 4 is a schematic diagram of a toilet bowl with a warm water washing toilet seat, which is an example of the toilet device of the present invention. In the embodiment shown in Fig. 4, the toilet device comprises a toilet bowl and a warm water washing toilet seat provided on top of it, and this warm water washing toilet seat is a device that discharges reformed water.

[0089] The warm water washing toilet seat comprises a generation unit 2, a discharge unit 3, a detection unit 8, a control unit 9, a casing 12, a toilet lid, and a toilet seat. The toilet lid is pivotally supported on the casing 12 so as to be able to open and close freely, but is not necessarily provided. The toilet seat is pivotally supported on the casing 12 so as to be able to open and close freely. In the embodiment shown in Fig. 4, modified water is discharged (sprayed) as mist M from the discharge unit 3.

[0090] (Casing) The casing 12 may include a deodorizing fan, a heater for generating hot water, a mechanism for discharging tap water to clean the bowl surface, a nozzle for washing private parts, etc. Furthermore, the functions of the mechanism for cleaning the bowl surface and the nozzle for washing private parts may also be performed by a discharge unit provided in the device 1 for discharging reformed water. For example, if the discharge unit 3 provided in the device 1 for discharging reformed water is a nozzle, it may have a drive unit that extends in the axial direction and a mechanism that protrudes outside the casing 12 when extended.

[0091] The generation unit 2, discharge unit 3, and control unit 9 are housed inside the casing. The detection unit 8 may be provided inside the casing 12 or may be provided externally. If it is provided internally, it has the configuration shown in Figure 2, and a signal from the detection unit 8 provided in the casing 12 is sent to the control unit 9.

[0092] <Operation of the Toilet Device> After a user relieves themselves in the toilet with a warm water washing seat, they leave the seat. A sensor provided in the detection unit 8 detects that the user has finished using the toilet, and sends a signal to the control unit 9. The sensor provided in the detection unit 8 may be a sensor that detects whether the user has sat down and / or left the seat, or a human sensor that can detect human movement. Alternatively, it may be a sensor that detects whether the toilet door is open or closed, etc.

[0093] <Test 1: Field Test 1: Reproduction of Hydrophobicity of Toilet Bowl Surface Due to Urine and Identification of the Cause> (Preparation of Test Samples) As test samples, a piece of sanitary ware measuring 1 cm x 4 cm and 2 mm thick (hereinafter referred to as "Test Piece 1") and a test piece in which a thin film was formed on an acrylic plate (Acrylite EX manufactured by Mitsubishi Chemical) using a paint containing a monomer with a hydrophilic organic functional group (hereinafter referred to as "Test Piece 2") were prepared.

[0094] Preparation of Test Specimen 1 Slip for sanitary ware, prepared from raw materials such as silica sand, feldspar, limestone, and clay, was cast in a plaster mold. The resulting molded body was dried, then spray-coated with a glaze having the composition shown in Table 1, fired at 1100-1200°C, and cut to the above size. The cut fired body was then washed with detergent ("Clean Ace S" by AS ONE Corporation), the detergent was rinsed off with tap water, and the body was further rinsed with purified water and allowed to air-dry to obtain Test Specimen 1. The static contact angle of water for Test Specimen 1 was 10°.

[0095]

[0096] Preparation of Test Piece 2 (Reagents) The following reagents were prepared: Polyfunctional acrylate: dipentaerythritol polyacrylate Polymerization initiator: a mixture of 1-hydroxycyclohexyl phenyl ketone and benzophenone in a weight ratio of 1:1 (Irgacure 500, manufactured by BASF) Solvent: 2-methoxyethanol Monomer having a hydrophilic organic functional group: potassium 3-((meth)acryloyloxy)propane-1-sulfonate

[0097] (Substrate and Pretreatment) An acrylic plate (Acrylite EX manufactured by Mitsubishi Chemical Corporation) was used as the substrate. The surface of this substrate was washed with a neutral detergent and rinsed with ion-exchanged water or ultrapure water. Water droplets on the surface of the substrate were blown off with an air blower, and the substrate was dried in a dryer at 60°C for 30 minutes.

[0098] (Formation of intermediate layer) A polymerization initiator was added at a weight concentration of 0.6% to a solution of polyfunctional acrylate:solvent = 33:67 (weight ratio), and the mixture was stirred with a stirrer for 1 hour to prepare a composition for forming an intermediate layer. This composition was applied to the pretreated substrate by spin coating (1500 rpm, 15 seconds). Immediately after application, the substrate was placed in a hot air drying oven and allowed to stand at 60°C for 10 minutes. Thereafter, an ultraviolet irradiation device (MDB15001N-01, manufactured by Sun Energy Co., Ltd.) was used to apply an ultraviolet ray with an integrated light dose of 1000 mJ / cm. ２ The coated surface was irradiated with UV light to cure the coating (measured with an ultraviolet integrating actinometer, C9536-254, manufactured by Hamamatsu Photonics KK).

[0099] (Formation of Surface Layer) A monomer having a hydrophilic organic functional group was dissolved in a solvent to a weight concentration of 10%. A polymerization initiator was then added to this solution at a weight concentration of 0.2%, and the mixture was stirred with a stirrer for 1 hour to prepare a composition for forming a surface layer. This composition was applied to the intermediate layer using a bar coater (#10). Immediately after application, the intermediate layer was placed in a hot air drying oven and allowed to stand at 60°C for 10 minutes. Thereafter, an ultraviolet irradiation device (MDB15001N-01, manufactured by Sun Energy Co., Ltd.) was used to apply an integrated light dose of 3 J / cm. ２ The coated surface was irradiated with UV light to cure the coating, and the coating was cured to a static contact angle of 15° (measured using an ultraviolet integrating actinometer, C9536-254, manufactured by Hamamatsu Photonics K.K.). To remove uncured components, the coating was washed with a neutral detergent, rinsed with ion-exchanged water or ultrapure water, and left to dry at room temperature for at least 1 hour, yielding test piece 2. The static contact angle of water on test piece 2 was 15°.

[0100] (Installation of test samples) Test samples (test pieces 1 and 2) were attached with aluminum tape to the front of the bowl of a PureRest toilet (TOTO Corporation) installed in the women's restroom on the 5th floor of Research Building No. 3 at the General Research Institute of TOTO Corporation (Motomura, Chigasaki City, Kanagawa Prefecture).

[0101] (Field Test) Three test subjects urinated in a toilet bowl with the test sample installed, and then flushed the toilet. The urination was performed at intervals of at least one hour. For test piece 1, samples were collected at the 1st, 3rd, 5th, 10th, and 15th urinations, and for test piece 2, samples were collected at the 10th, 45th, and 76th urinations. Each test piece was dried at 30°C for one hour, and then the static contact angle of water was measured.

[0102] (Test Results) The results for Test Piece 1 are shown in Figure 5(a), and the results for Test Piece 2 are shown in Figure 5(b). For Test Piece 1, the static contact angle of water increased to 40° after just one urination, and increased to 100° after 10 urinations. For Test Piece 2, the static contact angle of water increased to 70° after 10 urinations, and increased to 80° after 45 urinations.

[0103] <Identifying the cause of hydrophobicity of a hydrophilic toilet bowl due to urine> As in the above field test, a test sample (test piece 1) was attached to the front surface of the toilet bowl, and after 7 days it was collected and observed and analyzed for components.

[0104] (SEM Observation) Test piece 1 was observed under an electron microscope. The electron microscope observation was performed using an ultra-high resolution field emission scanning electron microscope (Hitachi Regulus 8220). The results are shown in Figure 6. From Figure 6, it was confirmed that dirt was attached to the entire surface of the test sample as if it were a coating. It was thought that this coating of dirt was the substance causing the hydrophobicity.

[0105] (Elemental Analysis by EDX) When this film-like dirt was analyzed by EDX, it was found to be an organic substance containing C, N, and O, as shown in FIG.

[0106] (Component Analysis by FT-IR) The IR spectrum of the test piece 1 was measured using FT-IR (Spectrum 2000 / PerkinElmer) to analyze the components of the film-like dirt. The analysis conditions were as shown in Table 2.

[0107]

[0108] As a result, as shown in FIG. 8, amide 1 (1654 cm), a band characteristic of proteins, was detected. －１ ) and amide 2 (1539 cm－１ ) was detected. Therefore, it was determined that the cause of the hydrophobicity of the hydrophilic toilet bowl was proteins contained in urine.

[0109] <Test 2: Laboratory Test - Evaluation of Protein Removal Ability by Modified Water> (Preparation of Modified Water) Free Chlorine Water Pt / IrO ２ The electrodes were immersed in tap water, and electrolysis was performed by applying a current to generate water containing free chlorine (hereinafter referred to as "free chlorine water"). 10 mL of this free chlorine water was dispensed into a water sampling bottle, and a single dose of free chlorine reagent for SWIFTEST (Hach) was added and mixed, and the free chlorine concentration in the free chlorine water was quantified using a pocket residual chlorine meter (Hach). For evaluation, the current applied was changed to adjust the free chlorine concentration to a predetermined value and used.

[0110] Ozone Water Tap water was passed through a water purifier MP02-3 (Mitsubishi Chemical Cleansui Corporation), and the water from which free chlorine had been removed was stored in a bottle. Next, a current was passed through a commercially available diamond electrode while the free chlorine-removed water was passed through, and the free chlorine-removed water was electrolyzed to produce water containing ozone (hereinafter referred to as "ozone water"). The ozone concentration of the ozone water was measured by collecting the sprayed ozone water at a position 13 cm away from the spray nozzle described below, and then sampling the collected ozone water with an ozone concentration measurement kit (Ozone AccuVac Ampules HR pk25, Hach), placing it in a portable absorptiometer (DR1900, Hach), and quantifying the ozone concentration using the ozone concentration measurement mode. For evaluation, the current was adjusted to a predetermined ozone concentration and used.

[0111] Hydrogen Peroxide Solution Commercially available hydrogen peroxide solution (FUJIFILM Wako Pure Chemical Industries, Ltd., product number 081-04215) was diluted with purified water (Kobayashi Chemical Industry Co., Ltd.) that does not contain free chlorine or ozone to adjust to a predetermined concentration.

[0112] (Method of Discharging Modified Water) The prepared modified water was stored in a rectangular parallelepiped container (80 mm x 50 mm x 30 mm). The container containing the modified water was connected to a water passage for spraying "Clean Disinfecting Water" (registered trademark) provided in a warm water washing toilet seat (Washlet Apricot F3A, TOTO Corporation, product number TCF4733AKS#NG2) via a polyurethane tube. Furthermore, a pump was installed in the middle of this polyurethane tube to supply the modified water from the container containing the stored modified water to the water passage. That is, in this test, a discharge unit provided in the warm water washing toilet seat was used to spray "Clean Disinfecting Water," and various modified waters were discharged by spraying from the spray nozzle constituting this discharge unit. The "warm water washing toilet seat" is equipped with an electrolysis device that generates "clean disinfectant water," a spray nozzle that sprays the "clean disinfectant water" onto the surface of the toilet bowl, and a water passage that connects the electrolysis device and the spray nozzle and sends the "clean disinfectant water" to the spray nozzle. The "clean disinfectant water" is electrolyzed water generated by the electrolysis device and is modified water that contains free chlorine as an active ingredient.

[0113] (Urine Collection) The entire amount of urine collected from the beginning to the end of urination was collected in a 250 mL wide-mouth bottle (Eye Boy, AS ONE Corporation, product number 5-002-03) and used for the test.

[0114] (Preparation of Test Samples) Test pieces 1 and 2 identical to those in Test 1 were prepared as test samples.

[0115] (Evaluation of removability of proteins attached to test samples using modified water) 1. Immersion step As shown in Figure 9, the test samples were arranged in a container, 20 mL of urine was added, and the container was left to stand for 10 minutes. After 10 minutes, the test samples were collected using tweezers.

[0116] 2. Washing Step As shown in FIG. 10, the collected test sample was immersed in 1 L of purified water (Kobayashi Chemical Industry Co., Ltd.) using tweezers for 10 seconds and then pulled out.

[0117] 3. Drying Step After Step 2, the test sample was dried in a dryer at 30°C for 1 hour.

[0118] Steps 1 to 3 were repeated 10 times.

[0119] 4. Protein Removal Process Using Modified Water As shown in Figure 11, a test sample with protein attached was placed in an aluminum tray. The above-mentioned spray nozzle was fixed at a position 13 cm away from the test sample, and modified water was sprayed from the nozzle at a flow rate of 250 mL / min at the concentration and for the time shown in Table 3. The test sample was then dried at 30°C for 20 hours.

[0120] 5. Analysis Measurement of the static contact angle of water and quantitative analysis of the protein remaining on the surface of the test sample were carried out.

[0121] (Static Contact Angle of Water) After steps 1 to 4, the test sample was measured for its static contact angle without being subjected to a cleaning operation such as rinsing.

[0122] (Quantitative Analysis of Protein) After steps 1 to 4, the test sample was immersed in purified water and then immersed in a nonwoven fabric (apparent density: 0.2 g / cm ３ The nonwoven fabric was wiped with 10 mg of nonwoven fabric (10 mg of nonwoven fabric was used), then wiped dry with another nonwoven fabric to recover the protein. The wiped nonwoven fabric was placed in a 20 mL headspace vial (AS ONE Corporation), 2 mL of 6 mol / L hydrochloric acid was added, and the mixture was left to stand at 110°C for 12 hours to perform hydrolysis. The mixture was then dried on a hot plate at 120°C for 3 hours, and 2 mL of ultrapure water was added to dissolve the amino acids, creating a test solution. Additionally, bovine serum albumin (BSA) (Fujifilm Wako Pure Chemical Industries, Ltd., product number 013-15143) previously weighed was hydrolyzed using the same procedure to create a calibration curve solution.

[0123] Quantitative method: The test solution and the calibration curve solution were subjected to high performance liquid chromatography (HPLC) measurement using the following equipment and conditions. HPLC measurement equipment: Nexera Post-column Amino Acid Analysis System (Shimadzu Corporation) HPLC measurement conditions: Column: Shim-pak Amino-Na (Shimadzu Corporation) Ammonia trap column: ISC-30Na (Shimadzu Corporation) Mobile phase: Three-solution gradient amino acid mobile phase kit Na type (Shimadzu Corporation) Flow rate: 0.6 ml / min Reaction reagent: Amino acid analysis kit OPA reagent (Shimadzu Corporation) Flow rate: 0.2 ml / min Detector: RF-10AXL (Shimadzu Corporation) Excitation wavelength: 350 nm, fluorescence wavelength: 450 nm

[0124] The sum of the peaks in the spectrum obtained by HPLC measurement was regarded as the peak area value, and the protein amount was calculated based on a calibration curve prepared from the calibration curve solution.

[0125] (Test Results) The results are shown in Table 3 and Fig. 12. In Table 3, "◯" indicates that the static contact angle of water was less than 30°, and "×" indicates that the static contact angle of water was 30° or more. Table 3 and Fig. 12 confirm that free chlorine exhibits a hydrophilicity-maintaining effect at a CT value of 20 ppm-second or more, hydrogen peroxide at a CT value of 5 ppm-second or more, and ozone at a CT value of 2 ppm-second or more.

[0126]

[0127] <Test 3. Field Test 2: Fixation of proteins contained in urine due to limescale> A toilet "PureRest" (TOTO Corporation) with a sanitary ceramic bowl surface was installed in the women's restroom on the fifth floor of Research Building No. 3 at TOTO Corporation's General Research Institute (Motomura, Chigasaki City, Kanagawa Prefecture), and a one-year field test 2 was carried out. The conditions for field test 2 are shown in Table 4 below.

[0128]

[0129] After Field Test 2 was completed, a urethane sponge that had been pre-soaked with water was further soaked in neutral detergent, and this sponge was used to clean the toilet. After cleaning, the toilet was recovered, and the front surface of the toilet bowl was destroyed. The cross-sections of the recovered fragments of the front surface of the bowl were subjected to SEM observation and EDX elemental analysis in the same manner as in Test 1. Furthermore, the surfaces of the fragments were subjected to the same FT-IR component analysis as in Test 1, and the static contact angle of water was also measured.

[0130] (SEM observation and EDX elemental analysis) The results are shown in Figure 14. From Figure 14, it was confirmed that limescale, mainly composed of Si, had accumulated on the surface to a height of about 3 µm. It was also confirmed that this limescale contained a carbon component. (Component analysis by FT-IR) The carbon component contained in the limescale was analyzed using FT-IR. As a result, it was confirmed that the carbon component was protein. When the amount of protein was quantified using HPLC using the method described above, it was found to be 3.5 µg / cm ２ It was confirmed that the protein was contained in the scale. (Static Contact Angle of Water) The static contact angle of water was 78°, and it was confirmed that the surface was hydrophobic.

[0131] From the above results, it is thought that even on hydrophilic surfaces, the accumulation of protein-containing scale can lead to hydrophobic soiling that is difficult to remove even with cleaning. In other words, in order to prevent the long-term hydrophobicization of protein-containing scale that induces hydrophobicity on hydrophilic surfaces and to enable the removal of such scale with normal cleaning as described below, it is thought that it is necessary to make the surface hydrophilic in a specific way, in other words, to make the surface contain specific chemical species.

[0132] Test 4: Field Test 3 Accumulation of Proteins Contained in Urine Due to Limescale The following evaluation was carried out using the same test pieces 1 and 2 as in Test 1.

[0133] (Installation of test samples) Test samples (test pieces 1 and 2) were attached with aluminum tape to the front of the bowl of a PureRest toilet (TOTO Corporation) installed in the women's restroom on the fifth floor of Research Building No. 3 at the General Research Institute of TOTO Corporation (Motomura, Chigasaki City, Kanagawa Prefecture). Two toilets were prepared: one that discharged modified water and one that did not.

[0134] (Field Test Method) Field Test 3 was carried out using a toilet bowl in which a test sample was installed. The conditions for Field Test 3 were the same as those for Field Test 2, i.e., as shown in Table 4 above. After one week had passed, each test piece was dried at 30°C for one hour, and then the static contact angle of water was measured and the presence of water stains was visually confirmed.

[0135] (Test Results) The results are shown in Table 5. When the modified water was discharged, it was found that Test Piece 2 was able to suppress hydrophobicity caused by proteins compared to Test Piece 1. In addition, Test Piece 2 produced less water stains than Test Piece 1.

[0136]

[0137] <Test 5. Field Test 4: Removal of Protein-Containing Water Stains> (Test Sample Installation and Field Test Method) A field test was conducted for three months using the same method as in Field Test 3. After that, each test piece was dried at 30°C for one hour, and then the static contact angle of water was measured.

[0138] (Sliding Test) The following sliding test was carried out on each test piece that had undergone Field Test 4. First, a bathroom sponge (Scotch-Brite (registered trademark) Bath Shine Antibacterial Sponge (with special abrasive particles), manufactured by 3M Japan) soaked in ion-exchanged water was prepared. The surface of the prepared sponge was pressed against the surface of each test piece after Field Test 4 with a load of 80 g / cm. ２ The test piece was pressed against the surface with a pressure of 0.01 MPa and slid back and forth three times. After the sliding, it was visually confirmed whether the water stains formed on the surface of each test piece had been removed. After the sliding test, the test piece was dried at 30°C for 1 hour, and then the static contact angle of water was measured.

[0139] (Test Results) The results are shown in Table 6. The water stains on the surface of Test Specimen 1 could not be removed by the sliding test, and the static water contact angle of the surface could not be reduced to less than 30°, i.e., the hydrophilicity could not be restored (recovered). On the other hand, the water stains on the surface of Test Specimen 2 could be removed by the sliding test, and the static water contact angle of the surface could be reduced to less than 30°, i.e., the hydrophilicity could be restored (recovered).

[0140]

[0141] Test 6. Field Test 5: Verification of the Effect of Modified Water on Maintaining Hydrophilicity (Test Method) A toilet (TOTO Corporation's "Neorest" (registered trademark)) installed in the women's restroom on the fourth floor of the R&D building at TOTO Corporation's General Research Institute (Motomura, Chigasaki City, Kanagawa Prefecture) was used as the toilet device. For this test, two toilets were prepared: one using a modified water discharge device and one without a modified water discharge device. Modified water with a hypochlorous acid concentration of 2 ppm was used as the modified water, and the modified water was discharged onto the bowl surface of the toilet for 10 seconds immediately after use. The toilet was used an average of 15 times per day, and after one month, the spread of water droplets 5 seconds after flushing was visually observed to evaluate whether hydrophilicity was maintained.

[0142] (Test Results) In the toilet bowl that did not use the modified water discharge device, the bowl surface became hydrophobic, but in the toilet bowl that used the modified water discharge device, the bowl surface remained hydrophilic. Furthermore, when the same test piece 2 as in Test 1 was attached to the front surface of the bowl and a similar test was performed, the same results were obtained.

[0143] <Test 7. Field Test 6 Combined Use of Hydrophilic Mode and Sterilization Mode: Switching the Discharge Sequence> (Test Method) As in Test 6, a toilet installed in the women's restroom on the fourth floor of the R&D building at TOTO Corporation's General Research Institute was used as the toilet device. In this test, a toilet using a device that discharges modified water only in sterilization mode was compared with a toilet using a device that discharges modified water in both hydrophilic mode and sterilization mode. The toilet was used an average of 10 times per day, and the test period was one month. The conditions for each mode were as follows:

[0144] Hydrophilic mode: Modified water with a free chlorine concentration of 1 ppm is dispensed for 100 seconds immediately after the toilet has finished being used. Sterilization mode: Modified water with a free chlorine concentration of 1 ppm is dispensed for 10 seconds periodically (average 15 times / day) regardless of whether the toilet is being used.

[0145] (Test results) Visual inspection of the boundary between the accumulated water and the bowl surface revealed no microbial soiling on the bowl surface of any of the toilets. However, the front surface of the bowl became hydrophobic in the toilet using the modified water discharge device in sterilization mode only. On the other hand, the hydrophilic nature of the toilet, which discharged modified water in both hydrophilic and sterilization modes, was maintained.

[0146] <Test 8. Field Test 7 Hydrophilicity Maintenance Effect and Bactericidal Effect> (Test Method) As in Test 6, a toilet bowl installed in the women's restroom on the fourth floor of the R&D building at the TOTO Corporation General Research Institute was used as the toilet device. The modified water was discharged immediately after the toilet bowl had finished being used. The test conditions, i.e., the modified water discharged and the discharge conditions, were as shown in Tables 7 and 8. The test period was one month.

[0147]

[0148]

[0149] (Test Results) Under conditions 1 and 3 shown in Tables 7 and 8, the hydrophilicity of the toilet bowl surface was maintained by using modified water, but microbial soiling was visually confirmed at the boundary between the accumulated water and the bowl surface. On the other hand, under conditions 2 and 4, the hydrophilicity of the toilet bowl surface was maintained, and no microbial soiling was confirmed at the boundary.

Claims

1. A device for use with a toilet having a hydrophilic bowl surface, which dispenses modified water onto the bowl surface, comprising: a generator for generating modified water; and a discharger for discharging the generated modified water onto the bowl surface, wherein when the product of the concentration of the active ingredient contained in the modified water and the time for which the modified water is dispensed onto the bowl surface is defined as the CT value (ppm-seconds), A: the modified water is ozone water, and is dispensed with a CT value of 2 ppm-seconds or more and 100 ppm-seconds or less; B: the modified water is hydrogen peroxide water, and is dispensed with a CT value of 5 ppm-seconds or more and less than 1000 ppm-seconds; or C: the modified water is free chlorine water, and is dispensed with a CT value of 20 ppm-seconds or more and 300 ppm-seconds or less.

2. The apparatus of claim 1, wherein said hydrophilic bowl surface is a bowl surface containing hydrophilic organic functional groups on its surface.

3. The device according to claim 1 or 2, further comprising a detection unit or a signal receiving unit and a control unit, and discharging reformed water onto the bowl surface at a frequency of at least once every 10 uses of the toilet.

4. The device according to claim 3, wherein the modified water is discharged after the toilet has finished being used and / or after the toilet has started being used.

5. The device of claim 1 or 2, further comprising a sterilization mode different from said modes A, B or C.

6. The apparatus of claim 3 further comprising a disinfection mode different from said modes A, B or C.

7. The apparatus of claim 4, further comprising a disinfection mode different from said modes A, B or C.

8. A toilet device comprising: a toilet bowl having a hydrophilic bowl surface; and a device for discharging modified water according to claim 1.

9. A toilet device comprising: a toilet bowl having a bowl surface containing hydrophilic organic functional groups on its surface; and a device for discharging modified water according to claim 2.

10. A toilet device as described in claim 8 or 9, wherein the device for discharging the modified water further comprises a detection unit or a signal receiving unit and a control unit, and the modified water is discharged onto the bowl surface at a frequency of at least once every 10 uses of the toilet.

11. The toilet device according to claim 10, wherein the modified water is dispensed after the end of use of the toilet bowl and / or after the start of use of the toilet bowl.

12. The toilet apparatus of claim 8 or 9, further comprising a disinfection mode different from the modes A, B or C.

13. The toilet apparatus of claim 10, further comprising a disinfection mode different from said modes A, B or C.

14. The toilet apparatus of claim 11, further comprising a disinfection mode different from said modes A, B or C.

Images