JP2010137135A - Cleaning method and cleaning apparatus under low environmental load - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning method which is under a low environmental load and has a higher cleaning power, a cleaning unit performing the method, and a cleaning apparatus incorporating the cleaning unit. <P>SOLUTION: In the cleaning method, microbubbles are generated in electrolytic alkaline water as a cleaning solution, and brushing is performed while feeding the solution to a cleaning object. The cleaning unit includes a cleaning tank (102) storing the electrolytic alkaline water as the cleaning solution, a microbubble generating nozzle (103) generating the microbubbles in the cleaning tank (102), and a brush for brushing the treating object. The cleaning apparatus includes a cleaning unit cleaning the cleaning object, a rinse unit removing the cleaning solution attached to the cleaning object, and a drying unit dewatering and drying the cleaning object, wherein the above cleaning unit is used as the cleaning unit. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a method of cleaning a low environmental load for general industrial parts such as various substrates in a field where a cleaning liquid containing a trace amount of inorganic alkali can be applied to a cleaning process in a manufacturing process, and machined parts. And a cleaning device.

  In recent years, in the field of cleaning, techniques of electrolytic alkaline water and microbubbles have been developed for the purpose of reducing the environmental burden. Furthermore, electrolytic alkaline water as a cleaning liquid, electrolytic alkaline water production apparatus, microbubble generating nozzle, or a microbubble generating unit incorporating a pump is becoming commercially available. A cleaning method and a cleaning apparatus to which these techniques are applied are disclosed in, for example, the following patent documents.

  Patent Document 1 discloses a cleaning method and a cleaning apparatus having a cleaning process (liquid temperature: 40 to 90 ° C.), liquid draining, and drying processes using electrolytic alkaline water as a cleaning liquid.

  Patent Document 2 discloses a cleaning apparatus having an air blocking cleaning with electrolytic alkaline water as a cleaning liquid (the liquid temperature is increased in response to a change in pH or emulsification degree of the cleaning liquid), rinsing, and drying.

  Patent Document 3 discloses a cleaning method and a cleaning apparatus for ultrasonic cleaning using air bubbling electrolytic alkaline water as a cleaning liquid.

  Patent Document 4 discloses a cleaning device for ultrasonic cleaning (determination of cleaning time and liquid replenishment is performed by sound pressure and pH monitoring) using electrolytic alkaline water as a cleaning liquid.

  Patent Document 5 discloses a cleaning device using ultrasonic cleaning technology (cleaning fluid management based on oil concentration) using electrolytic alkaline water as a cleaning fluid.

  Patent Document 6 discloses a cleaning apparatus to which a processing liquid as a cleaning liquid, microbubbles (diameter 20 μm or less), and ultrasonic waves (5 to 100 MHz) are applied.

  Patent Document 7 discloses a batch-type and single-wafer-type cleaning method and apparatus using a liquid as a cleaning liquid, microbubbles (predetermined gas), and ultrasonic waves.

  Patent Document 8 discloses a cleaning method and a cleaning apparatus using pure water at room temperature as a cleaning liquid, nitrogen gas microbubbles (30 ppm or more), and ultrasonic waves.

  Patent Document 9 discloses a cleaning method having a configuration of an interface control agent-added aqueous solution, microbubbles, and oil-water separation as a cleaning liquid.

JP-A-10-192860 JP 2001-286835 A JP 2002-320934 A JP 2005-013886 A JP 2005-262155 A Japanese Patent Laid-Open No. 2005-093873 JP 2006-179765 A JP 2006-310456 A JP 2007-301529 A

  A known low-environmental load compatible microbubble application cleaning method and cleaning apparatus are disclosed as described above, which uses electrolytic alkaline water as a cleaning liquid, combined electrolytic alkaline water and ultrasound, and microbubble water. Although it is the content of combining microbubble water and ultrasonic waves as a cleaning liquid, as a result of evaluating the degreasing ability as a cleaning power by the present inventors, none of the above cases was sufficiently satisfactory. .

  Accordingly, an object of the present invention is to provide a cleaning method with a low environmental load and a higher cleaning power, a cleaning unit for performing the method, and a cleaning apparatus incorporating the cleaning unit.

  The cleaning method of the present invention includes a step of generating microbubbles in electrolytic alkaline water as a cleaning liquid, and a brush processing step while supplying microbubble electrolytic alkaline water to an object to be processed.

  Further, the cleaning unit of the present invention for carrying out this cleaning method includes a cleaning tank for storing electrolytic alkaline water as a cleaning liquid therein, and a microbubble generating nozzle for generating microbubbles in the cleaning tank. And a brush for brushing an object to be processed.

  Furthermore, the cleaning apparatus of the present invention includes a cleaning unit for cleaning an object to be cleaned, a rinse unit for removing the cleaning liquid adhering to the liquid to be cleaned, and a drying unit for draining and drying the object to be processed. The above cleaning unit is used as the cleaning unit.

  The present invention resides in a cleaning method in which electrolytic alkaline water, microbubbles, and brushes are combined, and a cleaning apparatus incorporating the cleaning method.

  According to the cleaning method of the present invention, it is possible to remarkably improve the cleaning power such as degreasing and particle removal and cleaning uniformity for various objects to be processed. The liquid temperature does not need to be as high as normal temperature (about 25 ° C.), and the consumption of electrolytic alkaline water as a cleaning liquid due to evaporation or the like can be reduced.

  Furthermore, electrolytic alkaline water contains only a trace amount of inorganic substances, and its main component is water. Therefore, unlike conventional non-aqueous and semi-aqueous cleaning liquids, the burden on the environment is extremely low.

  In the cleaning method of the present invention, first, microbubbles are generated in the electrolytic alkaline water using electrolytic alkaline water having a liquid temperature of room temperature (about 25 ° C.) as the cleaning liquid, and the microbubbles in which the microbubbles are generated are generated. While supplying bubble electrolytic alkaline water to the object to be processed, the object to be processed is subjected to a brushing process.

  And in the washing | cleaning unit of this invention for implementing this method, while providing the washing tank for storing the electrolytic alkaline water as a washing | cleaning liquid inside, the micro for generating microbubble in the electrolytic alkaline water in a washing tank A bubble generating nozzle is provided, and a brush for performing a brushing process on the workpiece is further provided.

  In the cleaning apparatus of the present invention, the cleaning apparatus includes a cleaning unit for cleaning the object to be cleaned, a rinse unit for removing the cleaning liquid attached to the liquid to be cleaned, and a drying unit for draining and drying the object to be processed. In the above, the cleaning unit is used as the cleaning unit.

  An embodiment of the cleaning method of the present invention will be described. In the cleaning method of the present embodiment, first, electrolytic alkaline water is stored in the cleaning tank 102, and microbubbles are generated in the electrolytic alkaline water. Supply water to the workpiece.

  Next, the object to be treated supplied with the microbubble electrolytic alkaline water is subjected to a brushing process, whereby oils and particles adhering to the object to be treated are removed.

  In addition, as a method of supplying the microbubble electrolytic alkaline water to the object to be processed, a method of putting the object to be processed in a cleaning tank storing the electrolytic alkaline water in which microbubbles are generated, or a microbubble electrolytic alkaline property in the cleaning tank Although the method of inject | pouring water into the area which brushes a to-be-processed object by a gravity system can be considered, any method may be sufficient.

  Next, an embodiment of the cleaning unit for carrying out this method will be described with reference to FIG. 1. FIG. 1 is a diagram showing a configuration of the cleaning unit 100 of the present embodiment.

  And the washing | cleaning unit of a present Example is the washing tank 102, the microbubble generation nozzle 103, the reliable pump 104 even if gas mixes, the heat exchanger 105 for adjusting the temperature of washing | cleaning liquid, and constant temperature. The water circulation device 106, the water flow meter 107, the air flow meter 108, the ball valves 209 and 110, the needle valve 111, the pressure gauges 112 and 113, and the brush 114 are configured, and the washing tank In 102, electrolytic alkaline water is stored as the cleaning liquid 101.

  The cleaning liquid 101 is circulated by the pump 104, and is adjusted to a predetermined pressure and flow rate by inverter control of the ball valves 109 and 110, the needle valve 111 and the pump 104.

  Further, in the equipment configuration of the cleaning unit 100, the indication value of the pressure gauge 112 is 0.4 MPa, the indication value of the pressure gauge 113 is 0.3 MPa, the indication value of the water flow meter 107 is 16 L / min, and the air flow meter The indicated value 108 is 0.8 NL / min.

  Further, the liquid temperature is adjusted to 24 to 25 ° C. by the heat exchanger 105 and the constant temperature water circulation device 106. As a result, the cleaning liquid 101 has a cloudy appearance.

  Next, the evaluation results of the cleaning method of this example will be described. In the evaluation of the cleaning method of this example, the detergency as the degreasing ability is a wetting index standard solution (manufactured by Wako Pure Chemical Industries, Ltd.) having various surface tensions ( JIS K6768) was obtained, applied to a test piece (solid surface) with a cotton swab, and an evaluation method for judging the wettability at that time.

  The obtained standard solutions have surface tensions of 32 mN / m, 34 mN / m, 36 mN / m, 37 mN / m, 38 mN / m, 42 mN / m, 45 mN / m, 50 mN / m, 52 mN / m and 62 mN / m. It was supposed to be. It means that as the standard solution having a larger surface tension gets wet, the amount of residual oily substance is smaller.

  In JP-A-11-217598, there is a correlation between the critical surface tension obtained with a wetting index standard solution manufactured by Wako Pure Chemical Industries and the amount of oily substance measured with a Fourier integral infrared spectrometer (JIR-WINSPEC50 manufactured by FT-IR JEOL). It is disclosed that there is a relationship. It is shown as a relative value when the amount of residual oily substance on the solid surface wetted by water (25 ° C.) having a surface tension of 72 mN / m is “1”. For reference, a correlation diagram is shown in FIG. 2, and the critical surface tension means the value of the surface tension of the standard solution that gets wet when the solid surface gets wet and does not get wet.

  In addition, the cleaning power as the particle removal capability has the effect of peeling off particles adhering to the object to be processed and preventing re-adhesion to the object due to the adhesion of particles to the microbubbles if there is a degreasing ability. Therefore, degreasing ability and particle removal ability were judged to be equivalent.

The test piece preparation method will be described with reference to FIG. 3. First, a test piece is prepared, oil is applied to the test piece with a cotton swab, industrial wiper is wiped, and then heat treatment (80 ° C. × 2 hours) After that, the degreasing ability was evaluated after washing, rinsing with city water, and draining with an air gun. The test piece uses a SUS304 stainless steel plate (57 ^mm × 40 ^mm × ^t 1.5 ^mm ), and as the oil, lubricating oil (additive zero product manufactured by Shin Nippon Oil Co., Ltd.), cutting oil (Rex Industries) MIYAGAWA100SW-R manufactured by Co., Ltd.) and edible sesame oil.

  Next, the cleaning process sequence for evaluating the cleaning method of the present embodiment will be described. In the evaluation process of the present embodiment, the test piece and the brush 114 are contained in the cleaning liquid 101 in which microbubbles are generated and become cloudy. The test piece was manually brushed for a predetermined time.

  FIG. 4 shows the degreasing ability of the cleaning liquid 101 (electrolytic alkaline water and city water) at a liquid temperature of 24 to 25 ° C. The critical surface tension of electrolytic alkaline water is about 45 to 50 mN / n, and the amount of residual oily substance (relative value) is 2 or less, which is sufficiently satisfactory.

  In the case of city water, although there is a certain degree of detergency with a critical surface tension of about 36 to 37 mN / m and a residual oily substance amount (relative value) of 30 or less, it is inferior to electrolytic alkaline water. As described above, the cleaning method combining the electrolytic alkaline water as the cleaning liquid 101, the microbubble generating nozzle 103, and the brush 114 can exhibit sufficient cleaning power even in a short time treatment of about 10 seconds.

(First form)
The first embodiment of the embodiment of the cleaning apparatus of the present invention will be described with reference to FIG. 5. The cleaning apparatus of the present embodiment removes a cleaning unit for cleaning an object to be cleaned and a cleaning liquid adhering to the liquid to be cleaned. In the cleaning apparatus provided with the rinsing unit for carrying out and the drying unit for draining and drying the object to be processed, the above-described cleaning unit is used as the cleaning unit. That is, the cleaning apparatus incorporates a cleaning unit for performing a cleaning method combining microbubbles and brushing while using electrolytic alkaline water as cleaning water.

  The present embodiment is a single-wafer type cleaning apparatus that performs a cleaning process while conveying a workpiece in a horizontal or inclined posture, and is optimal for a low environmental load cleaning process for a square substrate made of various materials.

  The basic configuration 400 is a loader 400-1, a cleaning unit 400-2, a rinse unit 400-3, a drying unit 400-4, an unloader 400-5, and a roller transport mechanism 400-6. And the washing | cleaning unit of this invention is integrated in the washing | cleaning unit 400-2.

  The rinsing unit 400-3 is manufactured with a single or a combination of existing techniques such as spraying with pure water and showering.

  The drying unit 400-4 is manufactured by an air knife method that is an existing technology.

  The cleaning unit 400-2 includes a cleaning tank 402 having a brush 403 and a roller 404 for conveying a workpiece therein, a microbubble generating nozzle 203, a supply line and an overflow line for the electrolyzed alkaline water 215 that is cloudy. An electrolytic alkaline water storage tank 401, a circulation of electrolytic alkaline water 215 and a pump 205 for containing air in the electrolytic alkaline water 215, a heat exchanger 206 and a constant temperature water circulation unit 207 for adjusting the temperature of the electrolytic alkaline water 215 to room temperature, and circulation A buffer tank 204 for establishing the system optimally, a dirt recovery unit 214 for removing dirt (oil, particles, etc.) from the cleaning tank 402 flowing into the system, and an electrolytic alkaline water supply unit 213 Produced with the configuration of.

  In addition, it may replace with this supply unit and may arrange | position an electrolytic alkaline water manufacturing apparatus. The microbubble generating nozzle 203 needs to adjust the circulation system to the optimum flow rate and pressure depending on the type. For this purpose, a water flow rate detector 208, pressure detectors 209 and 210, an air flow rate detector 211, and a reduced pressure detector 212 are provided.

  Here, it is important that mechanical means such as a pump should not be used for transferring the cloudy electrolytic alkaline water 215. If transported by this means, the cloudy electrolytic alkaline water 215 becomes a semi-transparent appearance, and the collapse of the microbubbles proceeds. This phenomenon is extremely undesirable considering the utility of crushing energy for cleaning.

  As shown in FIG. 5, the countermeasure is such that the electrolytic alkaline water storage tank 401 and the cleaning tank 402 are positioned so that the electrolytic alkaline water storage tank 401 is in the upper position, and the The electrolytic alkaline water 215 is supplied to the workpiece surface near the brush 403 by gravity.

(Second form)
The second embodiment of the embodiment of the cleaning apparatus of the present invention will be described with reference to FIG. 6. The cleaning apparatus of the present embodiment is also a cleaning unit for cleaning an object to be cleaned, as in the first embodiment. In the cleaning apparatus including the rinsing unit for removing the cleaning liquid adhering to the cleaning liquid and the drying unit for draining and drying the object to be processed, the above-described cleaning unit is used as the cleaning unit.

  And the 2nd form is a single wafer type washing device which gives a rotation to a work and performs washing processing, and in a manufacturing process, a round substrate etc. of the field which can permit the washing liquid which contains a little inorganic alkali Ideal for low environmental load cleaning.

  The basic configuration 500 includes a loader 500-1, a cleaning unit 500-2, a rinse / dry unit 500-3, an unloader 500-4, and a robot transport mechanism 500-5. The cleaning unit of the present invention is incorporated in the cleaning unit 500-2, but the content is the same as that of the third embodiment.

  The cleaning unit 500-2 is an existing technology, that is, a rotation mechanism unit 501, a workpiece holder 502, a cup 503, a brush 504, and a cup 503 for rotating a workpiece or a rotation (not shown). It is manufactured according to the contents of the lifting mechanism of the mechanism unit 501.

  The rinsing / drying unit 500-3 is basically the same as the cleaning unit 500-2, but does not require the brush 504, and instead of supplying the electrolytic alkaline water 215, a rotating rinse by injecting pure water. And rotating draining drying by blowing air or nitrogen gas.

  The present invention is characterized by a combination of electrolytic alkaline water, microbubbles, and brushing, thereby significantly improving the cleaning power such as degreasing and particle removal and the uniformity of cleaning for various objects to be processed. Since it is possible to improve the performance of various industrial substrates such as various substrates and machined parts in fields where it is possible to apply a cleaning liquid containing a trace amount of inorganic alkali to the cleaning process of the manufacturing process, Applicable to general cleaning for environmental impact.

It is a figure which shows the structure of the washing | cleaning unit of this invention. Correlation diagram of critical surface tension and amount of residual oily substance (relative value) Test piece creation method It is a figure for demonstrating the degreasing capability by the combination of a washing | cleaning liquid, a microbubble, and a brush. It is a figure for demonstrating the 1st form of the Example of the washing | cleaning apparatus of this invention. It is a figure for demonstrating the 2nd form of the Example of the washing | cleaning apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Cleaning unit 101 Cleaning liquid 102 Ultrasonic cleaning tank 103 Micro bubble generation nozzle 104 Pump 105 Heat exchanger 106 Constant temperature water circulation device 107 Water flow meter 108 Air flow meter 109, 110 Ball valve 111 Needle valve 112, 113 Pressure gauge 114 Brush 203 Microbubble generation nozzle 204 Buffer tank 205 Pump 206 Heat exchanger 207 Constant temperature water circulation unit 208 Water flow rate detector 209, 210 Pressure detector 211 Air flow rate detector 212 Decompression detector 213 Electrolytic alkaline water supply unit 214 Dirt collection unit 215 Electrolysis Alkaline water 400 Single wafer cleaning device (1) Basic configuration 401 Electrolytic alkaline water storage tank 402 Cleaning tank 403 Roll brush 404 Roller 500 Single wafer cleaning device (2) Basic configuration 501 Rotating machine Part 502 workpiece holder 503 cup portion 504 broom

Claims (5)

  A cleaning method, characterized in that microbubbles are generated in electrolytic alkaline water as a cleaning liquid, and brush processing is performed while supplying the liquid to an object to be processed.   The cleaning method according to claim 1, wherein the microbubble liquid is supplied to an object to be processed by a gravity method.   The cleaning method according to claim 1 or 2, wherein the temperature of the electrolytic alkaline water as the cleaning liquid is normal temperature (about 25 ° C). A cleaning unit for carrying out the cleaning method according to any one of claims 1 to 3,
A cleaning tank (102) for storing electrolytic alkaline water as a cleaning liquid therein;
A microbubble generating nozzle (103) for generating microbubbles in the cleaning tank (102);
A cleaning unit comprising a brush for brushing an object to be processed.   A cleaning apparatus comprising a cleaning unit for cleaning an object to be cleaned, a rinse unit for removing the cleaning liquid adhering to the liquid to be cleaned, and a drying unit for draining and drying the object to be processed. 5. A cleaning apparatus using the cleaning unit according to 4.

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