JP-7856121-B2 - Ozone water generator

Inventors

• 三浦 敏徳
• 加藤 直樹
• 西原 正己
• 杉本 啓

Assignees

• 株式会社明電舎

Dates

Publication Date

20260511

Application Date

20240319

Claims (6)

1. An ozone gas supply line capable of supplying ozone gas, The ozone gas is supplied via a gas-liquid mixer, and a circulation line circulates a solvent capable of dissolving the ozone gas, A control unit for controlling the ozone gas supply line, Equipped with, The aforementioned gas-liquid mixer is In a circulating state in which the solvent is circulating, a solvent flow path through which the solvent flows, An ozone gas introduction path is provided connected to the solvent flow path and introduces ozone gas supplied from the ozone gas supply line into the solvent flow path in the circulation state, It has, The aforementioned ozone gas supply line is A first on/off valve is provided in the ozone gas supply line and is capable of switching whether or not the ozone gas can flow in the ozone gas supply line, A pressure gauge is provided downstream of the first on/off valve in the ozone gas supply line, and is capable of measuring the gas pressure on the downstream side. It has, The control unit, The first on/off valve controls the flow by comparing the measured value of the pressure gauge in the circulation state with an arbitrary pressure threshold set to be less than or equal to the saturated vapor pressure of the solvent, which is used for comparison with the measured value. When the measurement value of the pressure gauge exceeds the pressure threshold, the first on/off valve is closed. When the measurement value of the pressure gauge falls below the pressure threshold, the first on/off valve is opened. An ozone water generating device characterized by the following features.
2. The ozone water generating apparatus according to claim 1 , characterized in that the control unit measures the temperature of the solvent in the circulation state and derives the vapor pressure of the solvent, which is set as the pressure threshold.
3. The ozone gas supply line is provided with a discharge line downstream of the first on/off valve in the ozone gas supply line, which is capable of discharging moisture that has flowed downstream. The ozone water generating apparatus according to claim 1, characterized in that the discharge line has a second on-off valve capable of switching whether or not water flows from the downstream side of the first on-off valve in the ozone gas supply line.
4. The control unit, The vapor pressure of the solvent, derived by measuring its temperature in the aforementioned circulation state, is set as the pressure threshold. The ozone water generating apparatus according to claim 3, characterized in that the second on/off valve is opened when the measured value of the pressure gauge becomes equal to or greater than the pressure threshold.
5. A sensor capable of detecting moisture flowing into the downstream side is provided downstream of the first on/off valve in the ozone gas supply line. The ozone water generating apparatus according to claim 3, characterized in that the control unit opens the second on-off valve when the sensor detects moisture flowing downstream of the first on-off valve.
6. The ozone water generating apparatus according to claim 1, characterized in that the control unit closes the first on/off valve when the measured value of the pressure gauge becomes greater than the supply pressure of the ozone gas.

Description

This invention relates to a technology that can contribute to the development of ozonated water generation devices. Ozone water, obtained by dissolving ozone in a solvent (such as pure water), has strong oxidizing properties and has been used for purposes such as sterilizing tap water and food. The use of ozonated water is considered environmentally friendly because ozone easily decomposes into oxygen, leaving no residual chemicals. In recent years, attempts to utilize ozonated water have been made in cleaning processes used in the manufacturing of various industrial components, such as precision electronic components (e.g., semiconductor elements and display components like FPDs). Research is underway to increase the concentration of ozonated water and ensure a stable industrial supply. Patent Document 1 discloses a method for increasing the concentration of ozonated water by first cooling (concentrating) ozone gas, re-vaporizing the resulting ozonated water, collecting the re-vaporized ozone gas (concentrated ozone gas) with a cooling collector, and then dissolving the collected material (liquid ozone or solid ozone) in water to obtain ozonated water. Patent Document 2 discloses a method for maintaining a high ozone concentration in the cleaning solution and facilitating the removal of the resist film (organic film) on a substrate by simultaneously dissolving ozone gas and carbon dioxide gas in raw water (for example, raw water at 25°C or below, preferably 5°C to 20°C) and then bringing the cleaning solution into contact with the resist film (organic film) on the substrate while the solution is heated to 45°C or above. Patent Document 3 discloses a system for producing ozonated water by mixing ozone gas from an ozone gas generator (in Patent Document 3, a device using oxygen gas as a raw material) with raw water using a gas-liquid mixer. This system includes an orifice between the ozone gas generator and the gas-liquid mixer, which prevents the ozone gas generator from entering a negative pressure state (i.e., a state below normal pressure (approximately 101.33 kPa)), thereby increasing the ozone gas dissolution efficiency. Patent Document 4 discloses a configuration that utilizes the exhaust ozone gas to increase the concentration of ozonated water, comprising an ozonated water circulation line for circulating ozonated water and an ozone gas contact mechanism (a permeable membrane made of fluororesin) for bringing the exhaust ozone gas discharged from the ozonated water circulation line into contact with raw water. Patent Document 5 discloses a method for producing ozonated water by mixing ozone gas from an ozone gas generator (in Patent Document 5, a device using oxygen gas as a raw material) with raw water using a gas-liquid mixer. The method involves passing the ozonated water (the ozonated water in the tank indicated by reference numeral 34 in Patent Document 5), which has become too low in concentration due to the raw water, through the gas-liquid mixer to increase the concentration of the ozonated water. Non-patent document 1 discloses that when ozone may undergo a rapid autodecomposition reaction due to external factors (e.g., triggers such as electrical sparks or contaminants that induce decomposition), CF4 gas may be applied as an inhibitor to suppress the autodecomposition reaction. While the configurations shown in Patent Documents 1 to 5 may allow for the generation of ozonated water with a certain ozone concentration (e.g., around 100 ppm), cleaning processes requiring relatively high oxidizing power will likely require even higher concentrations of ozonated water (e.g., 200 ppm or more in semiconductor device cleaning processes). Japanese Patent Application Publication No. 11-262782Patent No. 4296393Patent No. 4746515Patent No. 5213601Patent No. 7041466 Taiyo Nippon Sanso Technical Report No. 28 (2009) "Explosion Range Measurement Device" A schematic diagram illustrating the configuration of ozone water generator A according to an example.(a) is the saturated vapor pressure curve for water, and (b) is a water vapor pressure table.A schematic diagram illustrating the configuration of ozone water generator B according to the example.A schematic diagram illustrating the configuration of generating apparatus B1, which is a modified version of generating apparatus B.A schematic diagram illustrating the configuration of generating apparatus B2, which is a modified version of generating apparatus B.A schematic diagram illustrating the configuration of generating apparatus B3, which is a modified version of generating apparatus B.A schematic diagram illustrating the configuration of generating apparatus B4, which is a modified version of generating apparatus B. The ozonated water generation apparatus of the present invention is completely different from configurations that simply use a gas-liquid mixer, as shown in, for example, Patent Documents 3 and 5 (hereinafter referred to as the conventional