JP2013208539A - Radical water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide radical water with high oxidation reduction potential, capable of enhancing wettability of objects, including no salts and few impurities, with long lifetime of hydroxyl radical, and suitably used for applications such as precision cleaning water for semiconductors, etc., a hydrophilic agent, sterilizing/cleaning water, and an antistatic agent.SOLUTION: Ozone water obtained by dissolving ozone in water is used as raw material of radical water which contains hydroxyl radical generated by photocatalytic reaction and decomposition reaction of water and ozone caused by ultraviolet rays as a main component of active oxygen. Ozone concentration of the ozone water is equal to or higher than 4 mg/L, and oxidizing power of the hydroxyl radical can remain for 5 minutes or longer by keeping the hydroxyl radical in fine bubble generated in the radical water by an ultrasonic oscillator or by a fine bubble generator.

Description

  The present invention relates to radical water that can be used for applications such as cleaning water for semiconductors and the like, hydrophilic agents, sterilizing cleaning water, antistatic water, and the like.

Conventionally, the active oxygen is present in vivo and the natural world, superoxide anion radical (· O ₂ ^-), hydroxyl radical (OH ·), ozone (O3), hydrogen peroxide (H ₂ O _2), nitrogen monoxide (NO), hypochlorous acid (HOCl), singlet oxygen ( ¹ O ₂ ), and the like. These aqueous solutions are used for deodorization, sterilization, sterilization and the like because of their high oxidizing power. However, active oxygen species such as superoxide anion radical (.O ₂ ⁻ ) and hydroxyl radical (OH.) Have a short half-life and lack versatility. In order to solve this problem, (Patent Document 1) states that “an aqueous solution containing ions causes free electrons and holes (photons) induced by a photocatalyst irradiated with ultraviolet rays to react efficiently with water. By generating a large amount of active oxygen species and reacting with a solute in an aqueous solution, an active oxygen water containing an ionic species generated from the solute is generated, and has excellent bactericidal ability and a protozoan anthelmintic And active oxygen water generating method for generating active oxygen water having a function of maintaining an organic substance resolution for a long time.

JP 2008-272616 A

However, the above conventional techniques have the following problems.
(1) The technique disclosed in (Patent Document 1) is an active oxygen water containing various active oxygen species,
It has a function to keep sterilizing ability, anthelmintic ability, organic matter resolution, etc. for a long time, but since it contains gases and salts, when used for precision cleaning of semiconductors, etc., salts can cause contamination. Had problems.

  The present invention solves the above-mentioned conventional problems. It has a high oxidation-reduction potential, can improve the wettability of objects, has few impurities, has a long hydroxyl radical (OH.) Life, and precisely cleans semiconductors and the like. It aims at providing radical water which can be used suitably for uses, such as water, a hydrophilic agent, sterilization washing water, and an antistatic agent.

In order to solve the above conventional problems, the radical water of the present invention has the following configuration.
The radical water according to claim 1 of the present invention uses, as a raw material, ozone water in which ozone is dissolved in water, and hydroxyl radicals generated by photocatalytic reaction and water and ozone decomposition reaction by ultraviolet rays are converted into active oxygen. Radical water contained as a main component,
The ozone concentration of the ozone water is 4 mg / L or more, and the hydroxyl radicals are held in the microbubbles generated in the radical water by an ultrasonic oscillator or a microbubble generator, whereby the oxidizing power of the hydroxyl radicals For 5 minutes or more.
With this configuration, the following effects can be obtained.
(1) Since ultraviolet light is irradiated to ozone water, a large amount of hydroxyl radicals (OH.) Are generated by decomposing ozone and reacting with water, and hydroxyl radicals (OH.) Are also generated from water and oxygen by photocatalytic reaction. Since it is generated, radical water having a high concentration of hydroxyl radicals (OH.) Can be obtained.
(2) Since the concentration of ozone dissolved in water is 4 mg / L or more, the amount of ozone decomposed by ultraviolet rays is large, and a large amount of hydroxyl radical (OH.) Is generated by decomposition. A radical water having a high concentration of (-) and a high redox potential can be obtained.
(3) Since the hydroxyl radical (OH.) Is confined inside the generated fine bubbles, the hydroxyl radical (OH.) Can be held for a long time, and the lifetime of the radical water can be extended.
(4) Radical water mainly composed of hydroxyl radicals (OH.) Has excellent oxidizing power, high detergency, and amphoteric metals can be ionized without forming an oxide film. It can be suitably used for cleaning and the like.
(5) Since the generated hydroxyl radical (OH.) Reacts with other substances and returns only to water, it is excellent in safety for animals and plants and excellent in environmental protection.
(6) Since the oxidizing ability of hydroxyl radical (OH.), Which has strong oxidizing power among active oxygen species, remains for more than 5 minutes, it can be used in various applications such as precision cleaning water, hydrophilic agent, sterilizing cleaning water, antistatic agent, etc. It can be used and has excellent versatility.
(7) Since the hydroxyl radical (OH.) Can improve the wettability of the contacted hydroxyl radical (OH.), It can be used as a hydrophilic material for filter paper, glass, synthetic resin filters (films), clothing and the like.
(8) Radical water has bactericidal properties and decomposability of organic substances, and is a reaction with low-molecular hydroxyl radicals (OH.), So it reacts only on the surface even when contacted with high-molecular substances such as animals and plants. It can be used more safely for sterilization and cleaning of plants such as crops and animals such as humans, and safer than when using chemicals, and can also be used for sterilization and cleaning of building materials such as toilets and floors. Can be sterilized and washed.
(9) Since the hydroxyl radical (OH.) Exists in the radical water, it is possible to restore the bias of the surface of the substance due to static electricity and to suppress the risk of discharge.

In the present invention, radical water is water containing active oxygen species in active oxygen, particularly hydroxyl radical (OH.) As a main component.
Since reactive oxygen species such as hydroxyl radical (OH.) In radical water are unstable, it is difficult to specify the concentration directly, and it is preferable to specify the concentration by the redox potential. A radical water oxidation-reduction potential of 250 to 700 mV is preferably used. As the oxidation-reduction potential becomes lower than 250 mV, the concentration of active oxygen species tends to be low, and the oxidizing power and cleaning power tend to be low, which is not preferable. As the oxidation-reduction potential becomes higher than 700 mV, it is necessary to increase the contact time with the photocatalyst during the production of radical water, and it is necessary to reduce the flow rate of ozone water or increase the size of the apparatus. It is not preferable because it tends to lack in nature.

Here, as one method for generating hydroxyl radicals (OH.), Water and titanium oxide, tungsten oxide, zinc oxide, niobium oxide, molybdenum oxide, vanadium oxide, cadmium sulfide and the like are in contact with a photocatalyst such as There is a method of generating a photocatalyst by irradiating the photocatalyst with ultraviolet light having a wavelength of 400 nm or less. Further, hydroxyl radicals (OH.) Can also be generated by the decomposition reaction of ozone by ultraviolet rays or the decomposition reaction of water by ultraviolet rays of 185 nm or less.
Furthermore, it is believed that fine bubbles of 50 μm or less generate hydroxyl radicals (OH.) By thermally decomposing water molecules when the inside of the bubbles becomes high temperature and pressure when disappearing. Moreover, it is thought that the half life of active oxygen species, such as hydroxyl radical (OH *), can be lengthened because the generated hydroxyl radical (OH *) is caught in a bubble.

A method for generating ozone is not particularly limited, and a method of irradiating air with an ultraviolet ray having a wavelength of 200 nm or less to react with oxygen, a method of performing silent discharge or arc discharge in oxygen, or the like is used.
As the raw material ozone water, ozone water generated by these methods is dissolved in ultrapure water, pure water, ion-exchanged water, or the like with very few impurities.
The ozone concentration is preferably 4 mg / L or more. As the ozone concentration is lower than 4 mg / L, the generation concentration of hydroxyl radical (OH.) Is lowered, and the oxidizing power and detergency tend to decrease, which is not preferable. Further, the upper limit of the ozone concentration is not particularly limited as long as it reaches the saturated ozone concentration.
Instead of ozone water, high-purity water and ozone gas may be separately introduced into the system before irradiation with ultraviolet rays. Since the higher the purity of the water and the higher the solubility, ozone can be dissolved by mixing with fine bubble-like ozone gas.
Water having an electrical conductivity of 0.1 μS / cm or less, preferably 0.06 μS / cm or less at a temperature of 25 ± 2 ° C. is used.

  As a wavelength of the ultraviolet ray to be reacted with the photocatalyst, a wavelength of 100 to 400 nm is preferably used, and a wavelength of 170 to 400 nm is more preferably used. As the wavelength becomes shorter than 170 nm, even if quartz glass is used for the light-transmitting thin plate, the light transmittance is poor, the catalytic activity efficiency and the decomposition efficiency of water and ozone are poor, and the generation of hydroxyl radicals (OH.) The efficiency is poor and ozone tends to remain in the radical water, and as the wavelength becomes shorter than 100 nm, the tendency becomes remarkable, which is not preferable. Further, as the wavelength becomes longer than 400 nm, the activity of the photocatalyst hardly occurs, so that the generation efficiency of the hydroxyl radical (OH.) Is deteriorated, which is not preferable.

The fine bubbles for holding hydroxyl radicals (OH.) Are preferably fine bubbles of 50 μm or less. As the fine bubbles become larger than 50 μm, they tend to float up to the surface of the water, so that they hardly remain in water and tend to be unable to hold hydroxyl radicals (OH.) For a long time.
The method is not particularly limited as long as microbubbles can be generated, but an ultrasonic generator, a microbubble generator, or the like can be used.

Next, a method for producing radical water will be described.
The method for producing radical water includes: (a) ozone concentration in a light-transmitting water passage in which (a) a rectangular cross section having a short side dimension of 1 to 5 mm and a photocatalyst is coated on at least the long water passage surface side. A water flow step of allowing ozone water of 4 mg / L or more to pass; and (b) irradiating ultraviolet rays having a wavelength of 100 nm to 400 nm into the water flow channel from an ultraviolet light irradiation unit disposed on the outer side of the long side of the water flow channel. A radical generating step of causing decomposition of ozone and water and generating a hydroxyl radical as a main component of active oxygen species by the photocatalytic reaction of the photocatalyst; and (c) 50 μm or less in the downstream of the water passage by the fine bubble generating part. And a holding step for generating fine bubbles and holding the active oxygen species inside the fine bubbles.
With this configuration, the following effects can be obtained.
(1) From an ultraviolet ray irradiation unit disposed on the outer side of the long side in a light-transmitting water passage having a rectangular shape with a short side dimension of 1 to 5 mm and a photocatalyst coated on the long side water passage surface side Since the ultraviolet ray having a wavelength of 100 nm to 400 nm is irradiated into the water passage, the ozone water and the photocatalyst are efficiently irradiated with the ultraviolet ray, the ozone is decomposed and the photocatalyst is activated, and the ozone water comes into contact with the activated photocatalyst. Combined with this, radical water containing a high concentration of active oxygen species mainly composed of hydroxyl radical (OH.) Can be obtained in a short time.
(2) Since the fine bubbles are generated downstream of the water channel, the reactive oxygen species can be held inside the fine bubbles as soon as the reactive oxygen species mainly composed of hydroxyl radical (OH.) Is generated. , The hydroxyl radical (OH.) Can be held at a high concentration for a long time.
(3) By making the cross section of the water passage into a rectangular shape, in order to efficiently irradiate the ozone water in the water passage with ultraviolet rays, the short side dimension is narrowed to 1 to 5 mm, but the water passage area Can be made wider than pipe-shaped water passages with a diameter of 1 to 5φ, and the amount of radical water produced can be increased.

The water passage is formed by arranging at least two light-transmitting thin plates coated with a photocatalyst such as titanium oxide, tungsten oxide, zinc oxide, niobium oxide, molybdenum oxide, vanadium oxide, and cadmium sulfide, with the coating surfaces facing each other. It is desirable to do.
The distance between the thin plates (the dimension on the short side of the water passage) is preferably 1 to 5 mm. As the distance between the thin plates becomes narrower than 1 mm, the resistance of the water when passing through the water passage is large and it is difficult for water to flow. Therefore, the amount of radical water obtained tends to decrease significantly, and as the distance becomes wider than 5 mm, ozone As the UV irradiation density per water decreases, the amount of ozone water that comes into contact with the photocatalyst decreases, and the amount of hydroxyl radicals (OH.) Generated is less than the amount of water passing through the water passage. ) Is not preferable because only radical water having a low content tends to be obtained. The distance between the thin plates (dimension on the short side of the water passage) is the material of the water passage, the flow rate of water (flow velocity), the intensity of ultraviolet light (light quantity), the intensity of ultrasonic waves, the amount of fine bubbles generated, etc. Depending on the conditions, the distance (dimension) is not limited and can be appropriately selected.
The light-transmitting thin plate that forms the water passage may be any material as long as it transmits ultraviolet rays. However, it is preferable to use quartz glass, barium fluoride glass, or the like because of less impurity elution.

The fine bubble generating unit may be any unit as long as fine bubbles of 50 μm or less are generated in water, and an ultrasonic generator, a fine bubble generator, or the like can be used.
When the microbubble generator is an ultrasonic generator, one having a frequency of 0.8 MHz or more is preferably used. As the frequency becomes smaller than 0.8 MHz, the amount of fine bubbles generated decreases and the amount of active oxygen species that can be retained decreases, which is not preferable because the amount of hydroxyl radical (OH.) In the radical water tends to decrease. .

It is desirable that an ultraviolet reflecting part is formed on the ultraviolet irradiation part so as to cover the ultraviolet irradiation part. By forming the ultraviolet reflection part, the ultraviolet rays irradiated to the water passage can be reflected between the reflection parts facing each other, and the ultraviolet ray irradiated through the water passage can be concentrated on the water supply part. Ultraviolet rays can be efficiently applied to the photocatalyst in the water passage portion, the ozone decomposition efficiency is improved, and hydroxyl radicals (OH.) Can be efficiently generated. The reflectance of the ultraviolet irradiation part is preferably 80% or more. As the reflectivity becomes smaller than 80%, the amount of reflected UV light decreases, so the photocatalytic reaction and ozone decomposition amount per unit time decreases, and the generation efficiency of hydroxyl radical (OH.) Of radical water tends to decrease. Therefore, it is not preferable.
As the ultraviolet irradiation unit, it is only necessary to irradiate ultraviolet rays, and a mercury lamp, a xenon lamp, an LED lamp, or the like can be used.

The radical water according to claim 2 is the invention according to claim 1, wherein the water is ultrapure water.
With this configuration, in addition to the operation obtained in the first aspect, the following operation can be obtained.
(1) Hydroxyl radical (OH.) Has strong oxidizing power and will disappear immediately after reaction if there is an impurity. By using ultrapure water with very few impurities in water that dissolves ozone, And does not contain impurities such as microorganisms, the generated hydroxyl radicals (OH.) Are difficult to disappear, the active oxygen species mainly composed of hydroxyl radicals (OH.) Can be maintained at a high concentration, and the hydroxyl radicals Excellent (OH.) Stability.

The semiconductor cleaning water according to claim 3 has a configuration containing the radical water according to claim 2.
With this configuration, the following effects can be obtained.
(1) Active oxygen derived from ultrapure water that does not contain impurities. It is radical water mainly composed of hydroxyl radicals (OH.). Hydroxyl radicals (OH.) Have strong oxidizing power and only return to water after the reaction. Therefore, it can be suitably used for precision cleaning of the surface of a silicon wafer or the like by decomposition of organic matter or ionization of metal.
(2) It can be used in place of ozone and inorganic acids used for cleaning silicon wafers, etc., and the operator can work safely and discharge of hazardous waste liquid can be suppressed.

  When radical water is used as semiconductor cleaning water, it is desirable to use one having a high concentration of hydroxyl radicals (OH.) And no impurities. As ultrapure water, one having an electric conductivity of 0.055 μS / cm (25 ± 2 ° C.) or less is used.

  In the ionization of metals, when amphoteric metals are ionized by an oxidizing agent, oxygen-based oxidizing agents such as ozone and superoxide anion form an oxide film on the surface of the amphoteric metal and prevent ionization, whereas hydroxyl radicals (OH Since ()) is ionized by reaction with OH, an oxide film is not formed, and it is easier to ionize amphoteric metals than oxygen-based oxidants. Thereby, cleaning of the surface of a semiconductor or the like, which has been performed with an inorganic acid, can be replaced with radical water, and safety is higher than when an inorganic acid is used, and discharge of an inorganic acid waste liquid can be suppressed.

The hydrophilic agent according to claim 4 has a configuration containing the radical water according to claim 1 or 2.
With this configuration, the following effects can be obtained.
(1) Since the radical water contains hydroxyl radical (OH.), Wetting (hydrophilicity) of the material can be increased by infiltrating the radical water into the processed material, so that the processed material and water are easily compatible. Therefore, water permeability can be improved by using it for filter paper, glass, a synthetic resin filter (membrane), clothing and the like.

Here, the hydrophilic agent refers to a material that can improve the wettability of an object by spraying, coating, or dipping.
Since the hydroxyl radical (OH.) Contained in the radical water in this case has an affinity for water, the radical water is brought into contact with and reacted with materials such as filter paper, glass, synthetic resin filters (film materials), and clothing. Therefore, the wettability of the material can be increased, and the water permeability and water permeability can be increased.

The sterilization washing water according to claim 5 has a configuration containing the radical water according to claim 1 or 2.
This configuration has the following effects.
(1) Hydroxyl radical (OH.) In radical water has bactericidal properties, but has a low molecular weight and reacts only on the surface of animals and plants. Therefore, it can be sterilized without damaging the surface of animals and plants, and the hydroxyl radical (OH.) After the reaction only returns to water, so it can be safely used as sterilized washing water for human bodies and food.

  Since the radical water of the present invention retains oxidizing power for a long time, it can be used as it is under running water, and animals and plants can be sterilized and washed in a state where the concentration concentration immediately after the generation of hydroxyl radicals (OH.) Is high. Moreover, since it does not react with a substance having a high molecular weight on the surface and becomes water after the reaction, it is superior in safety to washing germs with chemicals or the like. In addition, it is possible to remove indoor viruses and microorganisms by spraying and the like, and it can be suitably used for disinfection and sterilization such as hospital infection.

By using the radical water of the present invention as antistatic water, it has the following actions in addition to the actions obtained in the first aspect.
(1) By spraying, applying, immersing, etc. antistatic water containing radical water on the object, the electrical bias on the object surface can be restored, so that static electricity is less likely to accumulate on the object. Generation of spark discharge or the like can be prevented.

As described above, according to the radical water of the present invention, the following advantageous effects can be obtained.
According to claim 1,
(1) Since the concentration of hydroxyl radical (OH.) Is high, the oxidizing power is excellent, and the oxidizing power is long-lasting, it is possible to provide radical water that can be used for various purposes.

According to claim 2,
(1) It is possible to provide radical water that can keep the hydroxyl radical (OH.) At a high concentration.

According to claim 3,
(1) It can clean organic substances and metals adhering to the surface of semiconductors, etc., and can be used as a substitute for ozone and inorganic acids to ensure the safety of workers and suppress the discharge of hazardous waste liquid. It is possible to provide semiconductor cleaning water that can be used.

According to claim 4,
(1) It is possible to provide a hydrophilic agent that can improve water permeability and water permeability of filter paper, glass, a synthetic resin filter (membrane), clothing, and the like.

According to claim 5,
(1) It is possible to provide sterilized washing water that can safely perform sterilization washing of human bodies and food.

The perspective view which looked at the hydroxyl radical water generating device from the front side Cross-sectional front view of main parts of hydroxyl radical water generator Cross-sectional side view of main parts of hydroxyl radical water generator Enlarged view of the ultraviolet irradiation part in the cross-sectional front view of the main part of the hydroxyl radical water generator Schematic diagram of a hydroxyl radical water generation system showing the flow of water when an ultrapure water device and an ozone water generator are connected upstream of the hydroxyl radical water generator The graph which showed the ratio of the oxidizing agent when the ozone concentration of the comparative water 1 was 100% Graph showing changes in oxidant concentration due to addition of chlorogenic acid Graph showing the change over time of redox potential Graph showing the residual proportion of phthalates Graph showing the concentration of metal ions produced versus the redox potential of radical water Graph showing aging of turbidity The graph which showed the degradation amount of the agrochemical in the test water 1 and the comparison water 9

Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to these examples.
(Hydroxy radical water generator)
A low-pressure mercury lamp (Kurihara Kogyo Co., Ltd .: 25-8UV-LAMP) that irradiates ultraviolet rays with a wavelength of 185 nm and an ultrasonic oscillator with a frequency of 1 MHz (Honda Electronics Co., Ltd .: W-357LS-160) are prepared. Then, the hydroxyl radical water generator shown in FIGS. 1 to 4 was prepared.
FIG. 1 is a perspective view of the hydroxyl radical water generating device of the first embodiment as viewed from the front side, FIG. 2 is a cross-sectional front view of the principal part of the hydroxyl radical water generating device of the first embodiment, and FIG. FIG. 4 is an enlarged view of the ultraviolet irradiation unit in the cross-sectional front view of the main part of the hydroxyl radical water generating device of the first embodiment.
1 to 3, 1 is a hydroxyl radical water generating device of the first embodiment, 1 a is a hydroxyl radical water generating unit housed in the hydroxyl radical water generating device 1 (FIG. 2), and 1 b is hydroxyl radical water generating. The bottom plate of the part 1a, 2 is a base part of the hydroxyl radical water generating apparatus 1 that supports the hydroxyl radical water generating part 1a, 3 is a leg part of the hydroxyl radical water generating apparatus 1 disposed at the bottom part of the base part 2, 4 is The covering member of the hydroxyl radical water generating device 1 formed by being divided into two at the center in the width direction in parallel with the length direction and covering the hydroxyl radical water generating portion 1a so as to cover the hydroxyl radical water generating portion 1a. The covering member rotating portion 4b disposed between the portion 2 and the bottom side of the covering member 4 and holding the covering member 4 in an openable / closable manner is provided on the upper surface of the covering member 4. Open and close The covering member retaining portion 5 to be fixed is an upper opening formed in a slit shape on the upper side of the side wall of the covering member 4, and 6 is disposed inside the covering member 4 so as to face the upper opening 5. An upper blocking portion (FIG. 2) that prevents leakage of ultraviolet rays from the upper opening 5 to the outside, 7 is a lower opening formed in a slit shape on the lower side of the side wall of the covering member 4, and 8 is a lower portion of the covering member 4. A lower blocking portion (FIG. 2), which is disposed on the inner side so as to face the lower opening 7 and prevents ultraviolet leakage from the lower opening 7 to the outside, is formed at the bottom of the base portion 2 and is hydroxyl radical water described later. An inflow port made of fluororesin (FIGS. 2 and 3) and 9a communicating with the water passage portion 11 of the generation unit 1a are connected to the inflow port 9 and made of fluororesin that allows water to flow into the hydroxyl radical water generation unit 1a. Inflow tube (Figs. 1 and 2), 9b is hydroxyl radical water An inflow portion (FIGS. 2 and 3) and 9c for inflow of ultrapure water, ozone water, or the like that has been formed in close contact with an ultrasonic transducer 27, which will be described later, at the bottom of the formation portion 1a. The water supply section (FIG. 2) and 10 are the inlet 9 for communicating the bottom part of the part 9b and the hydroxyl radical water generating part 1a and supplying the water accumulated in the inflow part 9b to the water passing part 11 of the hydroxyl radical water generating part 1a described later. And an ultrasonic oscillator (FIGS. 1 and 2), 10a as an ultrasonic oscillator 10 that is fixed to the bottom surface of the base 2 and applies ultrasonic waves of 0.5 MHz or higher to water. The power cord (FIGS. 2 and 3), 11 is a water passing portion (FIG. 2) of the hydroxyl radical water generating portion 1a formed of quartz glass so that the width of the water passage 12 is 1 to 5 mm, and 11a is water passing. The water flow portion fixing the lower end portion of the portion 11 to the upper surface of the base portion 2 The fixed part (FIG. 2) and 11b are the expanded part (FIG. 2) of the water flow part 11 formed by expanding to the ultrasonic oscillator 10 side at the lower end side of the water flow path 12, and 11d is the upper part of the water flow part 11. The lid portion 13 is covered with a thin plate of quartz glass having a thickness of 2 mm and coated with a photocatalyst such as titanium oxide on at least the surface of the water passage 12, and is attached to face the water passage surface of the water passage 12. The attached photocatalyst parts (FIGS. 2 and 3) and 14 are made of quartz glass, and the photocatalyst part fixing parts (FIGS. 2 and 3) for fixing the interval positions of the photocatalyst parts 13 in the water passage 12 are provided. The ultraviolet irradiation part (FIG. 2, FIG. 3) arrange | positioned on the both outer sides of the part 11 and 16 are the several mercury lamps (FIG. 2, FIG. 2) of the ultraviolet irradiation part 15 of the ultraviolet irradiation part 15 fixed by the mercury lamp latching | locking part 16a. 3) and 17 are arranged so as to cover the outer sides of the mercury lamps 16 on both the left and right sides. UV reflectors (FIGS. 2 and 3), 18 and 18 ′ for reflecting the ultraviolet rays radiated from the light guide 16 toward the photocatalyst portion 13 side are ultraviolet rays which hold the left and right ultraviolet reflectors 17 by the ultraviolet reflector screwing portions 18a. Reflector plate fixing portions (FIGS. 2 and 3), 18b fix the upper surface of the base portion 2 and the lower end portions of the respective ultraviolet light reflector fixing portions 18, 18 ′, and the ultraviolet light reflector fixing portion 18, An ultraviolet light reflector rotating part (FIG. 2) for rotatably holding 18 ', 19 has one end rotatably held by a rotating part 19a formed at the upper end of the ultraviolet light reflector fixing part 18, and the other end. Are engaged with a latching portion 19b formed at the upper end portion of the ultraviolet light reflector fixing portion 18 'and fixed at the upper ends of the ultraviolet light reflector fixing portions 18, 18' (FIG. 2), 20 Is the light of the water passing portion 11 at both ends in the longitudinal direction of the hydroxyl radical water generating portion 1a. Fluorine resin-made hydroxyl radical water outlets (FIG. 3) formed on the upper side of the catalyst part 13 and connected to a fluororesin take-out tube 20a (21) are on both sides in the longitudinal direction of the hydroxyl radical water generating part 1a. Tube support portions (FIG. 3) and 22 for supporting the take-out tube 20a, 22 are tube insertion openings (FIGS. 1 and 3) formed in the covering member 4 for inserting the take-out tube 20a into the take-out port 20, and 23 is a water passage. An overflow water discharge hole (FIGS. 2 and 3) and 23a formed in the center of the lid portion 11d in the longitudinal direction of the portion 11 are formed of a fluorine-based resin and fitted into the overflow water discharge hole 23 ( 2 and 3) and 23b are tubes made of fluororesin and connected to the overflow water discharge part 23a to discharge the overflowed water from the water flow part 11. A.

Next, the detail of the ultraviolet irradiation part 15 of the hydroxyl radical water production | generation apparatus 1 is demonstrated.
In FIG. 4, 11 c is a photocatalyst portion locking portion that is formed in a stepped shape on the contact surface (water flow surface side) of the water passage 12 with the photocatalyst portion 13, and 24 is locked to the lower end portion of the photocatalyst portion 13. 11, flange portions 24a formed on both sides of the lower end of the water passage portion 24a are synthetic resin water passage portion fasteners for connecting and fixing the flange portion 24 of the water passage portion 11 to the base portion 2 and the ultrasonic oscillator 10, and 25a and 25b are flange portions. Packings 26 provided on the upper and lower sides of the flange portion 24 to prevent water leakage from the portion 24 are provided between the water passage fastener 24a and the packing 25a, and a pressing plate for firmly holding the flange portion 24. , 27 is an ultrasonic transducer made of sapphire that oscillates ultrasonic waves by the ultrasonic oscillator 10, 28 is supplied from the water supply unit 9 c and flows through the water passage 12, and 29 is irradiated from the ultraviolet irradiation unit 15 to the water passage 12. UV, 30 is super An ultrasonic frequency of at least 0.5MHz issued in running water 28 direction from the wave oscillation unit 10.

Then, an ultrapure water production apparatus (Nippon Millipore Corporation: Milli-QSP) and an ozone water generation apparatus (Ecodesign Corporation: ED-OW-7) were prepared, an ultrapure water generation apparatus, an ozone water generation apparatus, They were connected with a fluororesin tube in the order of the hydroxyl radical water generator. The flow of water at this time is shown in FIG.
FIG. 5 is a schematic diagram of a hydroxyl radical water generation system showing a flow of water when an ultrapure water production apparatus and an ozone water generation apparatus are connected upstream of the hydroxy radical water generation apparatus.

(Test water 1, comparative water 1)
Next, test water and each comparative water were manufactured using the hydroxyl radical water production | generation system shown in FIG.
Ozone generated in the ozone water generator was dissolved in ultrapure water produced at a flow rate of 0.9 L / min by the ultrapure water production device to obtain ozone water having an ozone concentration of 6 mg / L. (Comparative water 1)
The ozone water was used as comparative water 1, and the water obtained by passing through the hydroxyl radical water generating apparatus and applying ultraviolet light and a photocatalyst irradiated with ultraviolet light and ultrasonic waves was used as test water 1. (Test water 1)

(Comparison water 2)
The water obtained by contacting the photocatalyst without irradiating UV light to ozone water and without applying ultrasonic waves without turning on the low-pressure mercury lamp and the ultrasonic oscillator of the hydroxyl radical water generator is comparative water. 2.

(Comparative water 3)
Compare the water obtained by removing the photocatalyst part of the hydroxyl radical water generator, turning on only the ultrasonic oscillator, irradiating ozone water without irradiating ultraviolet light, and allowing only the ultrasonic wave to act without contacting the photocatalyst Water 3 was used.

(Comparison water 4)
The water obtained by turning on only the ultrasonic generator of the hydroxyl radical water generator, irradiating the ozone water with ultraviolet light, allowing the ultrasonic wave to act, and bringing it into contact with the photocatalyst was used as comparative water 4.

(Comparative water 5)
Remove the photocatalytic part of the hydroxyl radical water generator, turn on only the low-pressure mercury lamp, compare the water obtained by irradiating the ozone water with ultraviolet rays without contacting the photocatalyst with ultrasonic waves. It was set to 5.

(Comparison water 6)
Only the low-pressure mercury lamp of the hydroxyl radical water generator is turned on, and the water obtained by contacting the photocatalyst irradiated with ultraviolet rays without applying ultrasonic waves to the ozone water is compared with the water 6 It was.

(Comparative water 7)
Remove the photocatalyst of the hydroxyl radical water generator, turn on the low-pressure mercury lamp and the ultrasonic oscillator, irradiate ultraviolet light without contacting ozone water with the photocatalyst, and remove the water obtained by applying ultrasonic waves. Comparative water 7 was used.

(Comparative water 8)
Directly connect the ultrapure water to the hydroxyl radical water generator, turn on the low pressure mercury lamp and the ultrasonic oscillator, do not irradiate the ultrapure water with ultraviolet light, and contact the photocatalyst without applying ultrasonic waves. The water thus obtained was designated as comparative water 8.

(Comparative water 9)
The ultrapure water obtained from the ultrapure water apparatus was used as comparative water 9.

(Comparative water 10)
The tap water was designated as comparative water 10.
Table 1 shows a list of the configurations in which the test water 1 and the comparative waters 1 to 10 are operated.

(Example 1: Change in ozone concentration)
In order to investigate the ratio of the oxidizing agent contained in the test water 1 and each comparison water, the change in the ozone concentration was confirmed.
First, 2 g of potassium iodide (manufactured by Hayashi Junyaku Kogyo Co., Ltd.) is added to 1 L of test water 1 and 1 to 7 of comparative water 1 and stirred, and left at room temperature of 20 ° C. for 20 minutes to sufficiently react. The amount of iodine liberated by the oxidizing agent was quantified by titration with 1.58 mg / L sodium thiosulfate (manufactured by Wako Pure Chemical Industries, Ltd.). The result of converting the concentration of the oxidant obtained from the result of iodine consumption into ozone concentration is shown in FIG.

FIG. 6 is a graph showing the ratio of the oxidizing agent when the ozone concentration of the comparative water 1 is 100%.
From FIG. 6, since the values of the comparative waters 1 and 2 are 100%, it was found that the ratio of the oxidizing agent does not change only by contacting the ozone water with the photocatalyst. In comparison waters 3 and 4, compared with comparison water 1, the ratio of the oxidizing agent is about 55%, and there is almost no change in the value. Therefore, in comparison waters 3 and 4, only the ultrasonic wave acts on the oxidizing agent. It was considered that the ratio of oxidant (ratio of ozone) decreased by applying ultrasonic waves of 1 MHz to ozone water. In test waters 1 and 5 to 7 in which ultraviolet rays were applied to comparative water 1 to 4, the ratio of the oxidizing agent in comparative water 5 in which ultraviolet light was irradiated to ozone water was reduced to about 15%. It was found that the ratio of the oxidant was drastically decreased as compared with. From this, it is estimated that ozone is decomposed by ultraviolet rays. Further, in the comparative water 6 in which the photocatalyst and the ultraviolet irradiation are combined, the ratio of the oxidant is about 10%, which is lower than that of the comparative water 5, but it can be understood from the ratio of the oxidant in the comparative water 7 and the test water 1. Thus, it has been found that the ratio of the oxidant tends to increase as the conditions (contact with the photocatalyst and the action of ultrasonic waves) applied to the ozone water increase.
From these facts, it is presumed that by applying ultraviolet rays or ultrasonic waves to ozone water, ozone is decomposed and oxidants other than ozone are generated in the water irradiated with ultraviolet rays. Furthermore, since it is known that active oxygen species are generated by the decomposition reaction of water by ultrasonic waves or ultraviolet rays or the photocatalytic reaction, it is assumed that oxidizing agents other than ozone are active oxygen species.

(Example 2: Qualitative characteristics of reactive oxygen species)
To examine which active oxygen species the oxidizing agent other than ozone is, prepare 90 μL of comparative water 4 and 6 and test water 1 and add 1.77 g of chlorogenic acid with hydroxyl radical (OH.) Scavenging ability did. After the addition, 100 μg of luminol was further added, and the amount of oxidant before and after the addition of chlorogenic acid was measured from the amount of luminescence of luminol measured using a chemiluminescence measuring device (manufactured by Atto Co., Ltd .: Luminescent Sensor Octa AB-2270). did. The result is shown in FIG.

FIG. 7 is a graph showing changes in the concentration of the oxidant due to the addition of chlorogenic acid.
The measured value is obtained by converting the concentration of the oxidant obtained from the light emission amount of luminol into the ozone concentration regardless of the type of the oxidant.
From FIG. 7, since the concentration of the oxidizing agent in the test water after adding chlorogenic acid in all of the test water 1 and the comparative waters 4 and 6, the oxidizing agent other than ozone is hydroxyl radical (OH.) It was confirmed that.
Moreover, since the oxidizing agent remained after the addition of chlorogenic acid, the comparative water 4 was found to be a mixed solution of ozone and hydroxyl radical (OH.). On the other hand, in comparative water 6 and test water 1, since the oxidizing agent was lost by the addition of chlorogenic acid, it was found that all the oxidizing agents were hydroxyl radicals (OH.).
From these results, it is presumed that ozone is completely decomposed by irradiating ultraviolet rays. Furthermore, in the result of Example 1, since the concentration of the oxidizing agent in the test water 1 is higher than that in the comparative water 6, a high concentration of hydroxyl radical (OH.) Can be obtained by combining ultraviolet rays, photocatalysts, and ultrasonic waves. It was found that it can be produced in water.

(Example 3: Measurement of change over time of oxidation-reduction potential)
In order to examine the lifetime of the generated hydroxyl radical (OH.), 0.3 L of comparative water 1, 4, 6, 8, 10 and test water 1 were prepared, and oxidation-reduction potentiometer (manufactured by Lutron Electronic Enterprise: YK- 23RP) was used to measure the time-dependent change in redox potential in a room at 25 ° C. These results are shown in FIG.

FIG. 8 is a graph showing the change with time of the oxidation-reduction potential.
From FIG. 8, the comparative water 1 containing only ozone showed a gradual decrease in oxidation-reduction potential, and the value hardly changed from 1000 mV even after 60 minutes from the start of measurement. In the comparative water 4 containing both ozone and hydroxyl radical (OH.), The oxidation-reduction potential gradually decreased for 60 minutes from the start of measurement, and about 20% decrease was observed from about 1000 mV to about 800 mV. . In Comparative Water 6 and Test Water 1 containing only hydroxyl radical (OH.), The oxidation-reduction potential was remarkably reduced until a few minutes later, and then gradually decreased until 60 minutes later. In Comparative Waters 8 and 10, no change was observed in the redox potential until 60 minutes after the start of measurement.
Test water 1 is considered to be almost the same as ultrapure water when the hydroxyl radical (OH.) Disappears, and after 60 minutes, the oxidation-reduction potential finally shows the same value as comparative water 8 which is the same as ultrapure water. Therefore, it was shown that the oxidizing power of hydroxyl radical (OH.) In test water 1 remained in water for 5 minutes or more.

(Example 4: Organic matter decomposability test)
In order to investigate the decomposability of hydroxyl radical (OH ·) organic matter, 0.2 L of test water 1 and comparative waters 1 and 9 were prepared, and 1.7 × 10 ⁻³ mg / L of dibutyl phthalate and phthalic acid n -Each 0.34 microgram of dioctyl was mixed and stirred, and it was made to react at 20 degreeC for 1 minute. Then, the residual ratio of phthalates was measured using a gas chromatograph / mass spectrometer (manufactured by Agilent Technologies: 7683B Series Injector-7890A GC System-5975C Inert XL EI / CI MSD). At this time, the ozone concentration of the water after passing through the ozone water generator was set to 6.5 to 6.7 mg / L. The results are shown in FIG.

FIG. 9 is a graph showing the residual ratio of phthalates. The measured values in FIG. 9 are ratios when the concentration of phthalates in the comparative water 9 is 100%. Moreover, since the density | concentration of the ozone water of the comparison water 1 and the density | concentration of the hydroxyl radical (OH *) of the test water 1 differ, the density | concentration of the ozone of the comparison water 1 and the density | concentration of the hydroxyl radical (OH *) of the test water 1 are the same. Thus, the measurement result of the test water 1 is converted.
From FIG. 9, the comparative water 1 was about 10% for dibutyl phthalate and less than 20% for n-dioctyl phthalate. In contrast, in test water 1, dibutyl phthalate was about 6% and n-dioctyl phthalate was over 10%. From this, it was confirmed that the radical water of the test water 1 has higher cleaning ability of organic matter than the ozone water of the comparative water 1.

(Example 5: Metal solubility test)
In order to investigate the ionization ability of radical water to metal, 0.051 g of zinc powder, 0.051 g of copper powder, and 0.05 of silver powder were prepared. Zinc powder is mixed with 200 mL of test water 1, copper powder and silver powder are mixed with 90 mL of test water 1, stirred at 25 ° C. for 30 minutes, fully reacted, and each metal ion concentration after reaction is measured. did. At this time, the ozone concentration of the water after passing through the ozone water generator was set to 6.5 to 6.7 mg / L. The result is shown in FIG.
The concentration of the hydroxyl radical (OH.) Decreases with time, and the concentration of the hydroxyl radical (OH.) Varies depending on the reaction with the metal. Therefore, the oxidation-reduction potentiometer (manufactured by Lutron Electronic Enterprise: YK-) 23RP), the metal powder was reacted while measuring the oxidation-reduction potential, and the oxidation-reduction potential was defined as the concentration of hydroxyl radicals (OH.).

FIG. 10 is a graph showing the concentration of generated metal ions with respect to the redox potential of radical water. In FIG. 10, since the ion concentration of silver is low, the value of silver is 100 times the actual measurement value.
From FIG. 10, it was confirmed that copper and silver have a positive correlation as the redox potential increases and the metal ion concentration tends to increase.
Further, since zinc is easily ionized, no correlation was found between the concentration of hydroxyl radical (OH.) And the concentration of metal ions. However, in the case of zinc, even when the oxidation-reduction potential was relatively low, a tendency that the metal ion concentration was high was confirmed.
From these facts, hydroxyl radical (OH.) Is effective for ionization of metals, and has a cleaning effect even for metals with a small ionization tendency, and also for amphoteric elements other than zinc (aluminum, tin, lead). It was confirmed that the effect can be expected.

(Wettability test)
In order to investigate the hydrophilicity of radical water, 200 mL of test water 1 and comparative waters 1 and 9 were prepared, and lubricating oil was prepared in a 300 mL capacity furan bottle (manufactured by Kurisu Chemical Industry Co., Ltd .: Benisan genuine strong B-115). Was added and stirred, and the change with time of turbidity after standing was measured at room temperature. The measurement time was 100 minutes every 10 minutes from 30 minutes after standing. Turbidity was measured using a digital turbidity meter (manufactured by Kyoritsu Riken: WA-PT-4DG). At this time, the ozone concentration of the water after passing through the ozone water generator was set to 6.5 to 6.7 mg / L.
The result is shown in FIG.

  FIG. 11 is a graph showing changes in turbidity with time. From FIG. 11, the turbidity at the start of the observation was about 20 NTU for both test water 1 and comparative water 1 and was similar. Thereafter, the turbidity of the comparative water 9 decreased by about 10% over time, but the test water 1 and the comparative water 1 showed no decrease in turbidity. From this, it is thought that the test water 1 is improving the wettability of lubricating oil like the comparative water 1, and the radical water of this invention has the effect | action which improves the wettability of the thing which contacted. It was confirmed that it can be suitably used as a hydrophilic agent.

(Agricultural chemical degradation test)
In order to examine the removal effect of radical water pesticides, 200 mL of radical water similar to test water 1 and comparative waters 1 and 9 was prepared, and pesticides prosimidone, etofenprox, bifenthrin, dietofencarb, zoxamide, 4-chloroaniline. 20 mg each of 2,4-dichloroaniline, bitartanol, 3-methylcholanthrene, pyrimethanil, pertan, cypermethrin, dichlorobenil, 4-nitrophenol, p, p'-dichlorodiphenyltrichloroethane, and after stirring, Let stand for minutes, and measure the concentration of each pesticide with a gas chromatograph / mass spectrometer (manufactured by Agilent Technologies: 7683B Series Injector-7890A GC System-5975C Inert XL EI / CI MSD). It was. At this time, the ozone concentration of the water after passing through the ozone water generator was set to 6.5 to 6.7 mg / L.
The results of test water 1 and comparative waters 1 and 9 are shown in FIG.

FIG. 12 is a graph showing the amount of agricultural chemicals decomposed in test water 1 and comparative waters 1 and 9. In FIG. 12, the results of test water 1 and comparative water 1 show relative amounts when the concentration of the agrochemical in ultrapure water is 100%.
From FIG. 12, it was found that in the test water 1, the pesticide was decomposed by radical water. In addition, the concentration of test water 1 in procymidone, 2,4-dichloroaniline, bitartanol, 3-methylcholanthrene, pertan, p, p'-dichlorodiphenyltrichloroethane is lower than that in comparative water 1 and is higher than that in ozone water. In some cases, the water decomposition power was higher. From this, it is considered that the radical water of the present invention can also be used for removal of agricultural chemicals remaining on the surface of crops and the like.

  The present invention has a high oxidation-reduction potential, can improve the wettability of the object, does not contain salts and does not generate a residue of radical water itself, has no impurities, and has a long hydroxyl radical (OH.) Life, Radical water that can be used for applications such as precision cleaning water for semiconductors, hydrophilic agents, sterilization / washing water for animals and plants, antistatic agents, and the like can be provided.

DESCRIPTION OF SYMBOLS 1 Hydroxyl radical water production | generation apparatus 1a Hydroxyl radical water production | generation part 1b Bottom plate 2 Base part 3 Leg part 4 Cover member 4a Cover member rotation part 4b Cover member latching part 5 Upper opening part 6 Upper blocking part 7 Lower opening part 8 Lower blocking portion 9 Inlet 9a Inflow tube 9b Inflow portion 9c Water supply portion 10 Ultrasonic oscillator 10a Power cord 11 Water passage portion 11a Water passage portion fixing portion 11b Widening portion 11c Photocatalyst portion locking portion 11d Lid portion 12 Water passage 13 Photocatalyst part 14 Photocatalyst part fixing part 15 Ultraviolet irradiation part 16 Mercury lamp 16a Mercury lamp locking part 17 Ultraviolet reflectors 18, 18 'Ultraviolet reflector fixing part 18a Ultraviolet reflector screwing part 18b Ultraviolet reflector rotating part 19 Ultraviolet reflection Plate latching portion 19a Rotating portion 19b Latching portion 20 Ejection port 20a Ejection tube 21 Tube support portion 22 Tube insertion port 23 Overflow Discharge hole 23a overflow water discharge portion 23b discharge tube 24 flange portion 24a passing water portion fastener 25a, 25b packing 26 pressing plate 27 ultrasonic transducer 28 flowing water 29 UV 30 ultrasonic

Claims (5)

Ozone water in which ozone is dissolved in water as a raw material, radical water containing hydroxy radicals generated by photocatalytic reaction and water and ozone decomposition reaction by ultraviolet rays as a main component of active oxygen,
The ozone concentration of the ozone water is 4 mg / L or more, and the hydroxyl radicals are held in the microbubbles generated in the radical water by an ultrasonic oscillator or a microbubble generator, thereby oxidizing the hydroxyl radicals. Radical water which remains for 5 minutes or more.   The radical water according to claim 1, wherein the water is ultrapure water.   A semiconductor cleaning water comprising the radical water according to claim 2.   A hydrophilic agent comprising the radical water according to claim 1. A sterilizing washing water containing the radical water according to claim 1 or 2.