JPH08112573A - Cleaner and cleaning method - Google Patents

Abstract

PURPOSE: To provide a cleaner without a pollutant being concentrated in a cleaning soln., exhibiting high detergency, suppressing the discharge of the pollutant outside the system and without causing environmental pollution. CONSTITUTION: Water or an aq. electrolyte soln. is electrolyzed in an electrolytic water generator 3 to generate acidic water and alakaline water, and a material to be cleaned is cleaned in the preceding stage with the obtained acidic water and alkaline water in a cleaning tank 1. The acidic or alkaline water which has not been used in the preceding stage is regenerated as pure water in a pure water generator 4, and the pure water is used for finish cleaning in a cleaning tank 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device used for cleaning and removing residues after soldering.

[0002]

2. Description of the Related Art A cleaning method using chlorofluorocarbon is known as a general method for cleaning and removing the residue after soldering, but in recent years, the use of chlorofluorocarbon tends to be restricted for environmental protection. , Non-CFC cleaning technology is desired.

On the other hand, alkaline water or acidic water obtained by electrolyzing water is excellent in cleaning ability and has been conventionally used for cleaning in various fields. Alkaline water has a strong degreasing action and a dissolving action for acidic substances, and has a high ability to remove organic substances. It is known that acidic water has an effect of removing inorganic substances such as oxides and hydroxides, and further has a bactericidal action and an astringent action. It is desirable that these alkaline water or acidic water for cleaning be electrolytically generated in the cleaning device, and there is an advantage that the device can be simplified such that it is not necessary to replenish the acid or alkaline chemical liquid, and no replenisher tank is required. .

A cleaning method using such electrolyzed alkaline water or electrolyzed acidic water is disclosed in, for example, JP-A-63-254.
In Japanese Patent Laid-Open No. 416 and Japanese Patent Laid-Open No. 63-254417,
A method for cleaning a contact lens using electrolytic alkaline water and acidic water containing hypochlorous acid is disclosed. Further, Japanese Patent Application Laid-Open No. 1-218454 discloses a method of introducing chlorine gas generated in another electrolytic cell into electrolytic alkaline water for cleaning and sterilization.

[0005]

However, in the above method, there are problems that the dirt component is concentrated in the cleaning liquid during use, the cleaning power is gradually reduced, and the electrode is deteriorated by the dirt component. In order to solve this, after a certain period of use, reverse electrolysis is carried out to wash the electrodes (JP-A-63-25).
4416), a method of cleaning the electrode surface by applying ultrasonic waves (JP-A-58-189551), an overflow path is provided on the electrolyzed acidic water side, and the circuit is appropriately changed to switch the electrolyzed acidic water to the electrolyzed alkaline water side. There has been proposed a method of washing the electrode by flowing it into the air (Japanese Patent Laid-Open No. 59-147693).

However, since these processes are required, the water channel system is complicated and the electrodes are insufficiently cleaned, so that it is difficult to stably maintain a high cleaning capability for a long period of time. In addition, each time the electrode is washed, waste water is discharged out of the system, which may cause an environmental impact.

This problem of drainage also occurs in, for example, an electrolytic alkaline water producing apparatus that uses water that has passed through an activated carbon type water purifier, and in order to regenerate the activated carbon, the water channel is switched at appropriate times to simultaneously generate electrolytic acidic water. It is known to regenerate carbon dioxide through activated carbon (Japanese Patent Laid-Open No. 5-57282), but at this time, organic substances having an acidic group are separated from the activated carbon, and a large amount of waste water containing this is generated. In addition, JP-A-4
No. 305927 discloses a method of supplying electrolytic ozone gas together with a cleaning agent. However, since this cleaning method is a one-step cleaning method, it is necessary to clean a cleaning product to which an acid or alkali component is strongly adhered. Not always enough. Furthermore, wastewater is recovered and used as condensed steam, but this re-heating consumes a large amount of energy, and dirty recovery steam may reduce the cleaning power and may contaminate the object to be cleaned. There is a need to.

In the present invention, however, the dirt components are not concentrated in the cleaning liquid, and the high cleaning power can be exerted for a long period of time. Further, without using CFC, the dirt components are discharged to the outside of the system. It is an object of the present invention to provide a cleaning device and a cleaning method that suppress and do not pollute the environment.

[0009]

As shown in FIG. 1, a cleaning apparatus of the present invention comprises an electrolyzed water generator 3 for electrolyzing water or an aqueous solution of an electrolyte to produce acidic water or alkaline water.
An electrolyzed water cleaning tank 1 for cleaning an object to be cleaned using the obtained electrolyzed acidic water or electrolyzed alkaline water; and a pure water generator 4 for producing pure water from the electrolyzed acidic water or electrolyzed alkaline water. It is provided with a pure water cleaning tank 2 for cleaning an object to be cleaned using the obtained pure water (Claim 1).

In the above structure, the electrolyzed acidic water or the electrolyzed alkaline water produced in the electrolyzed water generator 3 is used for the pre-stage cleaning as the cleaning water in the electrolytic water cleaning tank 1. Electrolyzed water consisting of electrolyzed acidic water or electrolyzed alkaline water has excellent detergency, and acid water is mainly used for removing inorganic compounds and alkaline water for removing acidic substances and organic compounds. Unused electrolyzed water is regenerated into pure water by the pure water generator 4, and the pure water cleaning tank 2
Used as finishing wash water in.

As described above, the stain can be effectively removed by performing the first-stage cleaning with the electrolyzed water having excellent cleaning power and further performing the final cleaning with pure water. Further, since the electrolyzed water that is not used is regenerated into pure water and used for finishing cleaning, cleaning drainage can be eliminated. The dirt component in the wash water is decomposed by oxidation or reduction on the electrode of the electrolyzed water generator 3 or is removed by being adsorbed on activated carbon or the like in the pure water generator 4, so that the dirt component may be concentrated. It can exhibit high cleaning power for a long time.

In addition to the above structure, the electrolytic water cleaning tank 1 or the pure water cleaning tank 2 may be provided with a means for supplying at least one selected from ozone and hydrogen peroxide water (claim 2). Specifically, a hydrogen peroxide generator 7 for synthesizing hydrogen peroxide using oxygen gas or hydrogen gas generated in the electrolyzed water generator 3 as a raw material is provided (see FIG. 2), and the obtained hydrogen peroxide is It is supplied to the electrolytic water cleaning tank 1 or the pure water cleaning tank 2 (claim 3). Alternatively, an ozone generator 8 for synthesizing ozone from pure water generated by the pure water generator 4 is provided (see FIG. 4), and the obtained ozone is stored in the electrolytic water cleaning tank 1 or the pure water cleaning tank 2. It may be supplied (claim 4).

Ozone or hydrogen peroxide has a high oxidizing ability and decomposes and removes organic substances. Therefore, when these are added to the washing water, the washing power is further improved. In particular, if a hydrogen peroxide generator 7 or an ozone generator 8 is provided and these are electrochemically synthesized by using hydrogen, oxygen, etc. by-produced in the electrolyzed water generator 3, ozone or peroxide can be externally generated. By-products can be effectively used without the need to replenish hydrogen.

Specifically, the electrolyzed water generator 3 has a diaphragm 31 which divides the inside of the container into two parts, and an anode electrode 32 and a cathode electrode 33 which are opposed to each other with the diaphragm 31 interposed therebetween. By electrolysis, electrolyzed alkaline water having a pH of 9 or more and less than 12 in which hydrogen gas is dissolved is produced on the cathode electrode 33 side, and electrolyzed acidic water is produced on the anode electrode 32 side (claim 5).

The electrolyzed alkaline water having a pH of 9 or more and less than 12 in which hydrogen gas is dissolved, which is generated in the electrolyzed water generator 3, is effective as cleaning water for cleaning and removing the residue after soldering. Hydrogen is 0.0 when the total pressure of the gas phase is 1 atm.
00139g (40 ° C) ~ 0.000079g (80
℃), dissolved in electrolyzed water. The hydrogen gas dissolved in the electrolyzed water reduces the tin oxide on the solder surface between the solder and the flux residue (removes white residue), and lifts the flux residue adhered to the solder surface. Washing water having an appropriate alkalinity of pH 9 or more and less than 12 acts on the flux residue, and the flux is micellar and removed.

Since the anode electrode 32 is positively applied to the cathode electrode 33, anions in the electrolyte are electrophoresed to the anode electrode 32 side. Among the anions collected in the vicinity of the anode electrode 32, the organic acid ions, which are the components of the flux, are oxidized at the anode electrode 32 and finally decomposed into carbon dioxide and water to be removed. Also, Bronsted acid ions such as halogen ions, carbonate ions and acetate ions change the electrolyzed water in the vicinity of the anode electrode 32 to acidic.

Since the cathode electrode 33 is negatively applied to the anode electrode 32, cations in the electrolyte are electrophoresed to the cathode electrode 33 side. The cations that migrate toward the cathode electrode 33 include alkali metal ions in the electrolyte, which change the electrolyzed water in the vicinity of the cathode electrode 33 to alkaline. At the cathode electrode 33, water is electrolyzed to generate hydroxide ions and hydrogen gas is generated.

The cathode electrode 3 of the electrolyzed water generator 3
As the three materials, noble metal, nickel, or stainless alloy, which has a small hydrogen overvoltage and easily generates hydrogen by electrolysis, is preferably used (claim 6). Examples of the electrolyte include carbonates, hydrogen carbonates, percarbonates (claim 7), and hydroxides (claim 8), which improve the detergency. It is desirable that the electrolysis in the electrolyzed water generator 3 be performed at 40 to 80 ° C. where hydrogen is easily absorbed by the electrolyzed water (claim 9).

After washing the object to be cleaned with the electrolyzed alkaline water having a pH of 9 or more and less than 12 generated in the electrolyzed water generator 3, the anode electrode 32 of the electrolyzed water generator 3 is washed. You may make it neutralize with the electrolysis acidic water produced | generated by the side (Claim 10). The alkaline cleaning water remaining on the surface of the object to be cleaned is dried by p
H may increase and cause solder corrosion,
This can be prevented by adopting the above cleaning method and performing neutralization cleaning.

[0020]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of the cleaning apparatus of the present invention, which is an electrolytic water cleaning tank 1 for pre-cleaning using electrolytic acidic water or electrolytic alkaline water, and finishing of the object to be cleaned using pure water. It has two cleaning tanks, a pure water cleaning tank 2 for cleaning.

The electrolytic water cleaning tank 1 includes an electrolytic water generator 3
One of the electrolyzed acidic water and the electrolyzed alkaline water (here, electrolyzed alkaline water (cathode water)) is supplied as cleaning water. The other electrolyzed water that is not used is
It is sent to the pure water generator 4 and regenerated into pure water there. The regenerated pure water is usually heated by the heater 5 together with the pure water supplied from the pure water supply tank 6 and then sent to the pure water cleaning tank 2 to be used for finish cleaning. The used cleaning water is sent to the electrolytic water generator 3 together with the cleaning water in the electrolytic water cleaning tank 1, and the above cleaning cycle is repeated.

Next, the details of each part of the cleaning device will be described.
The electrolyzed water generator 3 includes an anode electrode 32 with a diaphragm 31 interposed therebetween.
And a cathode electrode 33 facing each other, and a direct current is applied between both electrodes to decompose water. That is,
At the anode electrode 32, hydrogen ions H ⁺ are generated at the same time as oxygen is generated as shown in the formula (1), and the pH of the liquid is lowered to become acidic. H ₂ O → 1 / 2O ₂ + 2H ⁺ + 2e (1) The obtained electrolytic acidic water (anode water) is effective in removing inorganic substances such as oxides and hydroxides, and has a bactericidal action and an astringent action. . On the other hand, in the cathode electrode 33, the formula (2)
At the same time the hydroxide ion OH When hydrogen is generated as ^-
Is generated, the pH of the liquid rises and becomes alkaline. 2H ₂ O + 2e → H ₂ + 2OH ⁻ (2) The obtained electrolytic alkaline water (cathode water) has a degreasing action and an acid substance dissolving action, and has a high ability to remove organic substances.

In order to carry out the electrode reactions of the above (1) and (2), it is necessary that the liquid resistance is small enough to allow electrolysis, and water having a large liquid resistance is used for the cathode electrode 33 and the anode electrode 32. It is preferable to make the distance as small as possible, or to add an ionic substance to increase the conductivity of water for electrolysis. Generally, when a substance containing a large amount of ionic substances is washed, the ionic components contained in the washed water have a certain degree of conductivity, and electrolysis can be performed as it is. If electrolysis is difficult, use sodium chloride (NaCl) or sodium sulfate (Na ₂ SO
_An appropriate amount of ionic substance such as ₄ ) may be added. Especially Na
When Cl is added, the anode electrode 32 has the formula (3)
Chlorine gas is generated by this, and hypochlorous acid (HCl
O) and melts. 2Cl ⁻ → Cl ₂ + 2e (3) The electrolytic solution containing HClO has a sterilizing and bleaching action and has excellent detergency. Therefore, the electrolytic acid water can be used for more effective cleaning. .

As a material for the anode electrode 32, a corrosion-resistant noble metal such as platinum, gold, or iridium, a conductive oxide such as ferrite or ruthenium oxide, or graphite can be used. Cathode electrode 3
No. 3 is required to have excellent corrosion resistance under alkaline conditions, and various materials such as nickel, stainless steel, and titanium can be used in addition to the material forming the anode electrode 32.

The material of the diaphragm 31 is not particularly limited, but it is preferable that it has excellent heat resistance since hot water may be used. Further, when electrolyzed alkaline water is used for cleaning, when a cation exchange membrane is used as the diaphragm 31, the cation component is concentrated in the electrolyzed alkaline water and the anion component can be removed. It is effective when you want to remove it. Conversely, when it is desired to concentrate only the anion component, an anion exchange membrane may be used.

In addition to the function of generating acidic water, the anode electrode 32 has the function of electrolytically oxidizing organic contaminants contained in the wash water to finally decompose it into carbon dioxide gas and water. It has the effect of extending the life of the activated carbon in the water regenerator 4. Further, when ozone or hydrogen peroxide is added in the pure water finish cleaning, it has an effect of decomposing these into oxygen and water, and extending the life of the ion exchange resin in the pure water regenerator 4.

Of the electrolyzed acidic water and electrolyzed alkaline water thus obtained, electrolyzed alkaline water (cathode water)
Is sent to the electrolytic water cleaning tank 1, and the electrolytic acidic water (anode water) is sent to the pure water generator 4.

In the pure water generator 4, the electrolyzed acidic water generated in the electrolyzed water generator 3 is regenerated into pure water. The pure water generator 4 may be of any one of heating distillation, reverse osmosis membrane method, etc., but in order to prevent the discharge of waste water, one that can effectively adsorb and remove organic substances and inorganic substances discharged in the washing process is used. preferable. Generally, first remove organic matter through activated carbon,
Next, the anion and cation components are adsorbed on the ion exchange resin to obtain pure water. The regenerated pure water is used as a pure water cleaning tank 2
By using it for the final cleaning, it is possible to efficiently perform cleaning without producing drainage.

The pure water thus obtained is sent to the pure water cleaning tank 2 and used for finish cleaning of the object to be cleaned. A heater 5 is preferably installed in the path for sending the regenerated pure water to the pure water cleaning tank 2, and the cleaning power can be increased by using warm water. As the heater 5, various things such as an electric heater and a steam heat exchanger can be used. In the present invention, in the electrolyzed water generator 3, the washing water is warmed by Joule heat during electrolysis, so the energy of the heater 5 may be small. Further, in order to replenish pure water evaporated by heating, it is preferable to provide a pure water replenishing tank 6 and replenish pure water as appropriate.

The cleaning in the pure water cleaning tank 2 and the electrolytic water cleaning tank 1 described above is performed by immersing the object to be cleaned in the cleaning tanks 1 and 2, or by spraying the cleaning water in the cleaning tanks 1 and 2 into a shower shape. This is done by spraying and contacting the object to be cleaned. The detergency of the wash water depends on the chemical properties of the wash water itself,
Depends on temperature, pressure, and flow state and degree (agitation speed, turbulent flow, laminar flow rate). Especially, since the action of temperature and pressure is large, washing water is supplied from nozzles 11 and 21 using a pump. It is most effective to spray on. In the case of immersion cleaning, it is preferable to bubble the cleaning tank with air or ozone-containing oxygen gas generated by an ozone generator described later, or attach an ultrasonic vibrator to the cleaning tank so that the cleaning water is sufficiently permeated.

By performing the two-step cleaning in this way,
Since the cleaning is performed effectively and the final cleaning is performed using the regenerated pure water, the drainage can be eliminated. In addition, the dirt component can be decomposed and removed in the process of producing the electrolyzed water and pure water, and the deterioration of the detergency can be prevented.

In order to wash and remove the residue after soldering, the pH of the washing water in the electrolytic water washing tank 1 is
Is adjusted to 9 or more and less than 12, and it is preferable to use electrolytic alkaline water in which hydrogen gas generated at the cathode electrode 33 is dissolved. If the pH is less than 9, the solubility of the acidic component of the flux residue is small and the detergency is reduced. In addition, tin may be corroded. If the pH is 12 or higher, tin, which is an amphoteric metal, may be corroded.

The pH of the electrolyzed alkaline water generated at the cathode electrode 33 can be adjusted by the electrolysis conditions.
That is, the pH of the cathode electrolyte can be adjusted to an arbitrary value depending on the cation concentration in the aqueous solution to be electrolyzed, the current density and the electrolysis time. For example, [Na
⁺ ] Ion concentration is 10 ^-5 mol / l or 10 ^-2 mol / l
If an electrolyte such as NaCO ₃ is added to water to electrolyze so as to be 1, there is now a relation of pH = −log [H ⁺ ] = 14 + log [OH ⁻ ], and in order to maintain electrical neutrality, [ Na ⁺ ] =
Because of the relationship of [OH ⁻ ], the liquid on the cathode electrode side can be finally made alkaline to a pH of 9 to 12. In other words, a liquid containing 10 ⁻⁵ mol / l or 10 ⁻² mol / l NaOH can be prepared.

The higher the current density during electrolysis, the faster this pH can be reached. In addition, since the acidic component of the flux is actually mixed during cleaning, the pH does not become alkaline as much as expected, so it is better to add the electrolyte so that the cation is added in a slightly larger amount than that. When the amount of acidic components in the flux is small, it is possible to control the pH to a sufficiently constant pH for a long time with the initial amount of cations added. A pH sensor may be attached to the washing tank so that the pH may be adjusted, and the electrolysis conditions (current density, time) may be controlled by this signal, or cations may be added from the auxiliary tank.

The electrolyte added during the electrolysis is not limited to the above, but lithium, sodium, potassium, cesium carbonate, hydrogen carbonate or percarbonate may be used. These have excellent detergency and, even if they remain, do not have a bad influence. From the viewpoint of solubility, pH and cost, sodium hydrogencarbonate is preferable. In addition, hydroxides of lithium, sodium, potassium and cesium can be used as the electrolyte, and exhibit excellent detergency. Solubility, p
From the aspect of H, sodium hydroxide is preferably used.

At this time, as a material for forming the cathode electrode 33, it is preferable to use platinum, palladium, iridium or other noble metals that readily generate hydrogen, nickel, alloys thereof, or stainless alloys. In particular,
From the viewpoint of cost and corrosion resistance, nickel, nickel-plated iron, or stainless alloy is preferable. As the stainless alloy, ferrite containing no nickel, martensitic stainless steel, or austenitic stainless steel containing nickel having good corrosion resistance may be used.

When the electrolysis in the electrolyzed water generator 3 is carried out at 40 to 80 ° C., hydrogen is easily absorbed in the electrolyzed water. When the temperature at which electrolysis is performed is less than 40 °, the viscosity of electrolyzed water increases and the reaction rate of electrolysis also decreases. Also, the detergency is reduced. When the temperature exceeds 80 °, the solubility of hydrogen decreases and the reducing power of electrolyzed water decreases.

After cleaning the object to be cleaned with the electrolytic alkaline water having a pH of 9 or more and less than 12 in which the hydrogen gas is dissolved,
Further, neutralization treatment may be performed with electrolytic acidic water generated on the anode electrode 32 side of the electrolytic water generator 3. As a result, the alkaline cleaning water remaining on the surface of the object to be cleaned can be neutralized and the corrosion of the solder can be prevented.

In the above embodiment, one electrolytic water cleaning tank is used, and only electrolytic alkaline water is used as cleaning water. However, a plurality of electrolytic water cleaning tanks are provided, one side is electrolytic acidic water and the other is electrolytic alkaline water. May be supplied, and the stains on the object to be cleaned having both acidic and alkaline substances as stain components can be effectively removed.

Further, if one or both of hydrogen peroxide (H ₂ O ₂ ) and ozone (O ₃ ) is added to the pure water cleaning tank 2, the finish cleaning ability can be further improved. These substances have a high oxidizing capacity,
Excellent ability to decompose and remove organic substances. H ₂ O ₂ may be replenished as a hydrogen peroxide solution in the form of chemical replenishment, and O ₃ may be synthesized by passing dry oxygen gas through an ozone discharge system. Chemical synthesis is more preferable because the system can be simplified. An example of a cleaning device incorporating a hydrogen peroxide generator or an ozone generator will be shown below.

FIG. 2 shows a second embodiment of the present invention,
A hydrogen peroxide generator 7 is arranged in the flow path from the heater 5 to the pure water cleaning tank 2. In the cleaning tanks 1 and 2, cleaning is performed by immersion. Other configurations are the same as those in the first embodiment.

The details of the hydrogen peroxide generator 7 are shown in FIG. The device 7 has a configuration in which the inside of the fuel cell 71 is divided into a plurality of chambers by an ion exchange membrane 72, and an anode electrode and a cathode electrode are joined to both sides of the compartment.
Uses a solid electrolyte membrane (perfluorosulfonic acid polymer) here. The inside of the cell 71 has an anode chamber 73 on the anode electrode side and a cathode chamber 74 on the cathode electrode side, and H ₂ (see formula (2)) generated at the cathode electrode 33 of the electrolyzed water generator 3 is introduced into the anode chamber 73. Road 75
Will be introduced more. On the other hand, in the cathode chamber 74, O ₂ (see formula (1)) generated in the anode electrode 32 of the electrolyzed water generator 3 is introduced from the introduction path 76, and pure water generated in the pure water generator 4 is introduced from the introduction path 77. be introduced. Then, the introduced O ₂ and H ₂ are electrochemically reacted to synthesize H ₂ O ₂ .

That is, in the anode electrode 32, the formula (4)
As a result, the hydrogen gas is ionized, and H ₂ → 2H ⁺ + 2e (4) At the cathode electrode 33, H ₂ O ₂ is generated by the formula (5). In addition to the equation (5), the reaction of the equation (6) proceeds at the cathode electrode 33. 2H ⁺ + O ₂ + 2e → H ₂ O ₂ (5) (4H ⁺ + O ₂ + 4e → 2H ₂ O (6)) Here, the H ₂ O ₂ generation reaction of the above formula (5) is expressed by In order to preferentially carry out the reaction of (6), it is preferable to use a noble metal such as gold having a high catalytic ability in the reaction of formula (5) for the cathode electrode 33. The material of the anode electrode 32 is preferably a noble metal such as platinum or iridium, which is capable of rapidly ionizing hydrogen and has excellent corrosion resistance.

In this way, the water containing H ₂ O ₂ produced at the cathode electrode 33 is introduced into the pure water cleaning device 2 through the outlet passage 78 at appropriate times or at all times. The acidic component and the organic component can be removed (defatted) by electrolytic alkaline cleaning in the cleaning tank 1, and the residual organic matter can be decomposed and removed by final cleaning with pure water containing hydrogen peroxide. Therefore, it is possible to prevent the dirt components in the pure water cleaning tank 2 from being concentrated. Further, H ₂ and O ₂ produced as by-products in the electrolyzed water generator 3 can be effectively used as a raw material for synthesizing H ₂ O ₂ .

FIG. 4 shows a third embodiment of the present invention. In this embodiment, an electrolytic water cleaning tank 9 is provided in addition to the electrolytic water cleaning tank 1 that uses electrolytic alkaline water, and electrolytic acidic water (anode water) generated in the electrolytic water generator 3 is supplied to generate electrolytic alkaline water. The three-step cleaning of electrolytic acidic water and pure water is performed. Further, an ozone generator 8 is arranged in the flow path from the heater 5 to the pure water cleaning tank 2. The cleaning in each of the cleaning tanks 1, 2, 9 is performed by spray cleaning using a pump. Other configurations are the same as those in the first embodiment.

FIG. 5 shows the details of the ozone generator 8. In the figure, the inside of the ozone generator 8 is an ion exchange membrane 81 made of a solid electrolyte membrane (perfluorosulfonic acid polymer).
Is divided into multiple rooms. An anode electrode and a cathode electrode are joined to both sides of the ion exchange membrane 81, and the anode electrode side is the anode chamber 82 and the cathode electrode side is the cathode chamber 83. For the anode electrode, it is preferable to use a material having a high oxygen generation overvoltage, such as lead dioxide. It is preferable to use a noble metal such as platinum for the cathode electrode. The pure water generator 4 is provided in the anode chamber 82 and the cathode chamber 83.
Introducing passages 84 and 85 for the pure water generated in (3) are respectively provided, and ozone is synthesized at the anode electrode 32 using pure water as a raw material according to the formula (7). Note that hydrogen gas is generated at the cathode electrode 33 according to the above formula (2). 3H ₂ O → O ₃ + 6H ⁺ + 6e (7) Here, in the anode electrode 32, an oxygen generation reaction also occurs at the same time according to the above formula (1).
In 2, the mixed gas containing oxygen and ozone is generated, and the ozone-containing pure water discharged from the discharge path 86 is supplied to the pure water cleaning device 2. The acidic component is removed by the electrolytic water cleaning tank 1, the alkaline component is removed by the electrolytic water cleaning tank 9, and the remaining dirt can be removed by the ozone-containing pure water. Further, by bubbling ozone-containing oxygen gas into the electrolytic water cleaning tank 1, organic contaminants can be decomposed and removed, concentration of contaminant components can be prevented, and the life of activated carbon in the pure water generator 4 can be improved. .

The pure water supplied to the ozone generator 8 does not necessarily have to be supplied to both the anode chamber 82 and the cathode chamber 83, but may be supplied to at least the cathode chamber 83. Further, the amount of water to be supplied may be such that the electrode surface is sufficiently wet. When supplying only to the cathode chamber 83,
Only water that has passed through the ion exchange membrane 81 from the cathode chamber 83 and reached the anode chamber 82 reacts to generate ozone-containing oxygen gas. Therefore, there is no possibility that the current efficiency will decrease due to the inclusion of impurities in the anode liquid, and there is no need to perform ion exchange treatment (removal of impurities) of the anode liquid.

In the ozone generator 8, oxygen gas is introduced into the cathode chamber 83, so that in the cathode electrode 33, in addition to the hydrogen generation reaction of the above formula (2), the formula (5) is used.
It is also possible to carry out the hydrogen peroxide generation reaction of
Pure water containing H ₂ O ₂ can be obtained from the cathode chamber 83. Since this reaction proceeds more advantageously as the pressure of oxygen gas increases, it is desirable to carry out the reaction in the cathode chamber 83 under a pressure of 1 atm or higher.

FIG. 6 shows a fourth embodiment of the present invention.
Cleaning is performed by using the ozone and H ₂ O ₂ -containing pure water thus generated. In the present embodiment, the ozone generator 8 is disposed in the flow path from the pure water generator 4 to the pure water cleaning tank 2, and the pure water generator 4 is connected to the cathode chamber 83 of the ozone generator 8. More pure water and oxygen are introduced from the anode chamber of the electrolyzed water generator 3. Then, the H ₂ O ₂ -containing pure water generated in the cathode chamber 83 is supplied to the pure water cleaning tank 2, while the ozone-containing oxygen gas generated in the anode chamber 82 is supplied to the cleaning tank 1 and the pure water cleaning tank using electrolytic alkaline water. Bubbling to 2 and immersion cleaning. The acidic component and the organic component are removed in the electrolytic water cleaning tank 1, and particularly the organic component is decomposed and removed by ozone. Further, the pure water containing ozone and hydrogen peroxide in the pure water cleaning tank 2 can decompose and remove the residual organic substances. Therefore,
It is possible to prevent concentration of dirt components in the cleaning tank and maintain high cleaning power for a long time.

Electrolytically synthesizing ozone by the ozone generator 8 shown in the third and fourth embodiments has the following advantages over the ozone generator utilizing discharge. 1) It is not necessary to use dry air or dry oxygen as a raw material,
No dryer required. 2) No high voltage discharge circuit is required. 3) Does not generate harmful NOx generated by discharge in air. 4) When synthesizing ozone water, the dissolution rate of ozone gas into water is slow, and it is difficult to generate high-concentration ozone water in a short time even if ozone gas is bubbled into water. When ozone is synthesized by the electrolytic method according to the present embodiment, the ozone saturated state is maintained on the electrode surface, so that high-concentration ozone water can be synthesized in a relatively short time.

It should be noted that ozone and hydrogen peroxide added to the cleaning water in each of the above-mentioned examples are easily decomposed and volatilized, and do not remain in the product and have an adverse effect.

[0052]

【Example】

Example 1 Next, in order to confirm the effect of the present invention, a cleaning test was conducted using the cleaning apparatus shown in FIG. As the object to be cleaned, 0.1 ml of a water-soluble flux for soldering was applied to a JISII type comb-shaped electrode (which was solder-plated on a Cu wiring pattern on a glass epoxy substrate).
The one added and remelted (220 ° C., 5 minutes) was used.

As the washing water, assuming that a flux component was mixed, the base liquid (pH 4) was prepared by dissolving the flux in pure water at a concentration of 1 g / l. As the electrolyzed water generator 3,
^Two platinum-plated titanium plates (platinum thickness: 2 μm) having an electrode area of 200 cm ² were used as electrodes 32 and 33 in a 3 l container, and the distance between electrodes was set to 5 mm. NaHCO ₃ : 0.01 mol / L was added to the base solution to prepare an aqueous electrolyte solution, which was introduced into the electrolyzed water generator 3.
When electrolysis was performed, when the constant current electrolysis was 10 mA / cm ² and the voltage was 20 V, the maximum p on the side of the anode electrode 32 was p.
H3 electrolyzed acidic water, maximum pH1 on the cathode electrode 33 side
Hydrogen saturated electrolyzed alkaline water of 1 was obtained (hydrogen dissolution amount 0.0001 g / l).

The hydrogen-saturated electrolyzed alkaline water having a pH of 10.8 obtained as described above was used as washing water, and the above-mentioned object to be washed was washed in the electrolytic water washing tank 1 (60 ° C., 1 minute) and then pure water. It was rinsed with pure water in a water washing tank 2 and dried with hot air. The degree of cleaning was evaluated by measuring the surface insulation resistance after application of 100 V for 1 minute in a constant temperature and humidity chamber at a relative humidity of 94% and a temperature of 40 ° C. using an insulation resistance measuring device VGM-BB manufactured by Ando Electric Co., Ltd. The evaluation method was the following three-stage evaluation, and the results are shown in Table 1. ◯: Surface insulation resistance> 10 ³ MΩ Δ: 10 MΩ ≦ surface insulation resistance ≦ 10 ³ MΩ ×: Surface insulation resistance <10 MΩ

Table 1 shows the cleaning method, visual observation and SEM.
(Scanning electron microscope) The degree of removal of the white residue judged by observation and the degree of etching of the solder part are also shown. The evaluation methods are as follows. Degree of white residue removal ○: Complete removal Δ: Slight removal ×: Almost residual solder part etching degree ○: No etching Δ: Slight etching ×: Large etching

[0056]

[Table 1]

(Embodiment 2) Next, in the same manner as in Embodiment 1 above, after washing with hydrogen-saturated electrolyzed alkaline water having a pH of 10.8, the acidic water (pH
A test for neutralizing and cleaning in 3.4) was conducted. After the neutralization cleaning, the same pure water cleaning and drying as in Example 1 were performed. The results are also shown in Table 1.

As is clear from Table 1, in both Examples 1 and 2, good results were obtained in terms of surface insulation resistance, the degree of white residue removal, and the degree of solder portion etching. In addition,
The surface insulation resistance value is as follows: Example 1: 2 × 10 ^{3 to} 6 × 10 ³ Example 2: 4 × 10 ³ to 1 × 10 ⁴ By comparison, it was found that the surface insulation resistance was slightly larger and the cleaning was performed better.

(Comparative Examples 1 to 4) Moreover, pure water was used as the cleaning water (Comparative Example 1), NaHCO ₃ or Na.
The same cleaning test was performed using the ones in which the pH of the base solution was adjusted with ₂ CO ₃ as shown in the table (Comparative Examples 12 to 4).
The results are also shown in Table 1.

As is clear from Table 1, the cleaning degree viewed from the surface insulation resistance is good except for Comparative Example 1 in which pure water cleaning is performed, but in Comparative Examples 2 and 3, the degree of white residue removal is insufficient. In Comparative Example 4, the degree of white residue removal was insufficient,
Moreover, the solder part was largely etched.

From the above, for cleaning the residue after soldering, hydrogen-containing alkaline electrolyzed water having a pH of 9 or more and less than 12 is particularly effective, and neutralizing cleaning with acidic water is more effective after cleaning. I understand that it is a target.

[0062]

INDUSTRIAL APPLICABILITY As described above, the cleaning apparatus of the present invention exhibits excellent cleaning power for a long period of time without the contamination components being concentrated in the cleaning water. Further, since it is a non-Freon cleaning technology, it is possible to eliminate the cleaning drainage and to suppress the discharge of dirt components out of the system, and since it does not pollute the environment, it has an industrially excellent utility value. Further, according to the cleaning method of the present invention, an excellent cleaning effect can be obtained, and after cleaning with electrolytic water in a weak alkaline region, neutralization is further performed with acidic electrolytic water, which may damage the object to be cleaned. Is small.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a cleaning device according to a first embodiment of the present invention.

FIG. 2 is an overall configuration diagram of a cleaning device showing a second embodiment of the present invention.

FIG. 3 is an overall sectional view of a hydrogen peroxide generator.

FIG. 4 is an overall configuration diagram of a cleaning device showing a third embodiment of the present invention.

FIG. 5 is an overall sectional view of an ozone generator.

FIG. 6 is an overall configuration diagram of a cleaning device showing a fourth embodiment of the present invention.

[Explanation of symbols]

 1 Electrolytic water cleaning tank 2 Pure water cleaning tank 3 Electrolytic water generator 4 Pure water generator 5 Heater 6 Pure water replenishment tank 7 Hydrogen peroxide generator 8 Ozone generator

Claims (10)

[Claims] 1. An electrolyzed water generator for electrolyzing water or an aqueous solution of an electrolyte to produce acidic water or alkaline water, and electrolysis for cleaning an article to be washed using the obtained electrolytic acidic water or electrolytic alkaline water. A water cleaning tank, a pure water generator for generating pure water from the electrolytic acidic water or electrolytic alkaline water, and a pure water cleaning tank for cleaning an object to be cleaned using the obtained pure water are provided. A characteristic cleaning device. 2. The electrolytic water cleaning tank or the pure water cleaning tank,
The cleaning device according to claim 1, further comprising means for supplying at least one selected from ozone and hydrogen peroxide. 3. A hydrogen peroxide generator for synthesizing hydrogen peroxide using oxygen gas or hydrogen gas generated in the electrolyzed water generator as a raw material is provided, and the obtained hydrogen peroxide is used in the electrolyzed water cleaning tank or pure water. The cleaning device according to claim 1, wherein the cleaning device is adapted to supply to a water cleaning tank. 4. An ozone generator for synthesizing ozone from pure water generated by the pure water generator is provided, and the obtained ozone is supplied to the electrolytic water cleaning tank or the pure water cleaning tank. The cleaning device according to claim 1. 5. The electrolytic water generator has a diaphragm that divides the interior of the container into two parts, and an anode electrode and a cathode electrode that are opposed to each other with the diaphragm interposed therebetween. The cathode electrode is formed by electrolyzing an aqueous solution of an electrolyte. Hydrogen gas melted on the side
The cleaning apparatus according to claim 1, wherein electrolytic alkaline water having an H9 or more and less than 12 is generated, and electrolytic acidic water is generated on the anode electrode side. 6. The cleaning apparatus according to claim 5, wherein the cathode electrode is made of a noble metal, nickel, or a stainless alloy. 7. The cleaning apparatus according to claim 5, wherein the electrolyte is carbonate, hydrogen carbonate, or percarbonate. 8. The cleaning device according to claim 5, wherein the electrolyte is a hydroxide. 9. The electrolysis in the electrolyzed water generator is
The cleaning device according to any one of claims 5 to 8, which is performed at 0 to 80 ° C. 10. A hydrogen gas is dissolved on the cathode electrode side by disposing an anode electrode and a cathode electrode opposite to each other with a diaphragm dividing the interior of the container sandwiched therebetween, and energizing both electrodes to electrolyze the aqueous solution of the electrolyte. Generates electrolytic alkaline water having a pH of 9 or more and less than 12 and electrolytic acidic water on the anode electrode side,
A cleaning method comprising cleaning an object to be cleaned with electrolytic alkaline water having a pH of 9 or more and less than 12 in which the hydrogen gas is dissolved, and then neutralizing the electrolytic acidic water.