JPH1085683A - Cleaning equipment - Google Patents

Abstract

(57) Abstract: In a cleaning apparatus using an organic solvent, by controlling the vapor flow of the organic solvent, the organic solvent vapor is concentrated around the object to be cleaned, and the organic solvent vapor is removed. Reduce the amount of suction and exhaust. SOLUTION: An organic solvent vapor 43 is formed on a surface of a cleaning object 20.
Is condensed, and in the cleaning apparatus for cleaning and drying the object to be cleaned 20, the organic solvent 31 retained at the bottom is heated, and the processing of the object to be cleaned 20 is performed in a steam cleaning tank 41 for generating an organic solvent vapor 43. By installing the cooling means 45 near the position, the vapor flow of the organic solvent is concentrated around the article 20 to be cleaned. In addition, the object to be cleaned 20 is previously converted into an organic solvent 3.
When immersion cleaning is performed in step 1, the organic solvent 31 accommodated in the immersion cleaning tank 32 is cooled, and the cooled organic solvent 3 is cooled.
In step 1, the object to be cleaned 20 is replaced at a low temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning apparatus for cleaning various objects to be cleaned such as a glass substrate for liquid crystal with an organic solvent, and more particularly to cleaning and drying by condensing vapor of the organic solvent on the surface of the object to be cleaned. A cleaning device for performing

[0002]

2. Description of the Related Art In the manufacturing process of various substrates, etc., after cleaning a substrate with an aqueous cleaning solution or water, foreign substances or water on the surface are further reduced by using a low boiling organic solvent such as isopropyl alcohol (IPA). Drying has been performed while removing the like. The substrate to be cleaned is dried by condensing the vapor of the organic solvent on the surface of the substrate and removing the foreign matter and moisture on the surface, and finally drying (volatilizing) the organic solvent on the surface of the substrate. . Such a drying method is suitable for an insulating substrate to which foreign matter such as dust easily adheres due to the influence of static electricity or the like, for example, a large glass substrate for a liquid crystal display device.

A conventional cleaning apparatus using an organic solvent will be described with reference to FIGS. For example, a plurality of substrates 1 whose surfaces are wetted by water are supported vertically by a basket 2, and in this state, are first sent to an organic solvent immersion cleaning step A. The immersion cleaning step A has a replacement tank 4 in which an organic solvent such as IPA 3 is accommodated, and the replacement tank 4 is provided with a circulation system including an overflow section 5, a circulation pump 6, and a circulation filter 7. . The substrate 1 to be cleaned is immersed in the IPA 3 at room temperature in the replacement tank 4,
The IPA 3 is replaced with water or the like adhering to the surface of the substrate 1.

[0004] The substrate 1 after the replacement of water or the like with the IPA 3 in the immersion cleaning step A is sent to a vapor cleaning (condensing / drying) step B having a vapor tank 8 of an organic solvent. Steam tank 8
For example, IPA 9 as an organic solvent stays in the lower part of the inside, and the temperature of the IPA 9 is increased by a heater 10 installed at the bottom of the steam tank 8 to generate IPA vapor 11. The substrate 1 that has passed through the immersion cleaning step A is transferred to a predetermined processing position in the vapor tank 8 that is filled with the IPA vapor 11, and the substrate 1 is cleaned by condensing the IPA vapor 11 on the surface of the substrate 1. And drying is performed.

Below the processing position of the substrate 1 in the steam tank 8,
A waste liquid receiving tray 12 is provided for collecting the IPA waste liquid condensed and dropped on the surface of the substrate 1, and these IPA waste liquids are discarded via a drain tank 13 and the like. Above the steam tank 8, a condensing coil 14 for circulating cold water and an exhaust duct 15 are provided to prevent the IPA steam 11 from flowing out of the steam tank 8.

In the above-described steam cleaning (condensing / drying) step B of the conventional cleaning apparatus, the substrate 1 as an object to be cleaned is
The IPA vapor 11 is transferred to the PA vapor 11 and condensed on the surface of the substrate 1. As shown in FIG.
The steam 11 basically flows toward the condensing coil 14 in the upper portion of the steam tank 8, and when cleaning a glass substrate or the like as the substrate 1, its heat capacity is small.
There is a problem that the flow of the A vapor 11 is hardly concentrated around the substrate 1. In addition, in the conventional cleaning apparatus, since IPA3 at room temperature (close to room temperature) is used in the immersion cleaning process A, the IPA vapor 11 and the substrate 1 are used in the steam cleaning process B.
Is small, which also prevents the IPA vapor 11 from concentrating around the substrate 1.

[0007]

As described above, in a conventional cleaning apparatus using an organic solvent such as IPA, the I
It was difficult to efficiently concentrate the PA vapor around the object to be cleaned, and there was a problem that the cleaning density (cleanability), the cleaning efficiency, and the like were low. In addition, of the generated IPA vapor, except for the vapor condensed on the substrate surface, it is basically condensed and collected by the condensing coil at the upper part of the vapor tank. There has been a problem that the amount of IPA vapor sucked and exhausted by the exhaust duct also increases, and the amount of IPA used increases.

In view of the above, in a conventional cleaning apparatus using an organic solvent, by controlling the vapor flow of the organic solvent, the vapor of the organic solvent can be concentrated around the object to be cleaned. It is an issue to reduce the amount of suction and exhaust of the vapor of the organic solvent.

SUMMARY OF THE INVENTION The present invention has been made to address such a problem and aims to improve the cleaning density (cleanability) and cleaning efficiency by concentrating the vapor of an organic solvent around the object to be cleaned. It is another object of the present invention to provide a cleaning apparatus that reduces the amount of organic solvent used.

[0010]

According to a first aspect of the present invention, there is provided a cleaning apparatus for cleaning and drying an object to be cleaned by condensing an organic solvent vapor on a surface of the object to be cleaned. And the organic solvent retained at the bottom is heated to generate vapor of the organic solvent, and the object to be cleaned is transported to a predetermined processing position in the vapor flow of the organic solvent. A steam cleaning tank, and a cooling unit that is installed near the processing position of the object to be cleaned in the steam cleaning tank and cools the vapor of the organic solvent, and the vapor flow of the organic solvent is reduced by the cooling unit. It is characterized in that it is configured to concentrate around the object to be cleaned.

A cleaning apparatus according to a second aspect of the present invention is a cleaning apparatus for cleaning an object to be cleaned with an organic solvent. An immersion washing tank to be immersed, an immersion washing section having a cooling means for cooling the organic solvent housed in the immersion washing tank, and heating the organic solvent retained at the bottom to vaporize the organic solvent. And a steam cleaning tank in which the object to be cleaned having passed through the immersion cleaning unit is transferred to a predetermined processing position in a vapor flow of the organic solvent, and processing of the object to be cleaned in the steam cleaning tank. A steam cleaning unit that is installed near a position and has a cooling unit that cools the vapor of the organic solvent, and is configured to concentrate the vapor flow of the organic solvent around the object to be cleaned by the cooling unit. To have It is a symptom.

In the cleaning apparatus according to the first aspect, cooling means is provided near the processing position of the cleaning target in the steam cleaning tank, and the vapor of the organic solvent is cooled near the processing position of the cleaning target. By cooling the organic solvent vapor near the processing position of the object to be cleaned, the vapor flow of the organic solvent from the bottom to the top of the steam cleaning tank concentrates near the processing position of the object to be cleaned. That is, the vapor flow of the organic solvent concentrates on the object to be cleaned. Therefore, it is possible to improve the cleaning density (cleanability), the cleaning efficiency, and the like of the object to be cleaned, and it is possible to reduce the amount of suction and exhaust of the organic solvent vapor.

In the cleaning apparatus according to the present invention, in addition to the cooling means in the steam cleaning tank, a cooling means for cooling the organic solvent is provided in the immersion cleaning tank for immersing the object to be cleaned in the organic solvent. Accordingly, the cold-substituted object to be cleaned is transferred to the steam cleaning tank. As described above, by lowering the temperature of the cleaning target transferred to the steam cleaning tank, the vapor flow of the organic solvent can be further concentrated on the cleaning target. Therefore, the cleaning density (cleanability) of the object to be cleaned
And cleaning efficiency and the like can be further improved.

[0014]

Embodiments of the present invention will be described below.

FIG. 1 is a diagram showing a schematic configuration of an embodiment of the cleaning apparatus of the present invention. The main part of the cleaning apparatus shown in FIG. 1 is composed of an immersion cleaning step A and a steam cleaning step B. In each of these steps A and B, for example, a plurality of substrates 21 as objects to be cleaned 20 are stored. It has a transfer mechanism C for sequentially transferring the baskets 22.

A plurality of substrates 21 as objects to be cleaned 20
For example, it has been subjected to a cleaning step using a water-based cleaning liquid, water, or the like in another separately installed cleaning apparatus, and for example, water is attached to the surface thereof. Such a plurality of substrates 21 are supported vertically by the basket 22, and are sent to the immersion cleaning step A and the steam cleaning step B in this state.

The immersion cleaning step (immersion cleaning section) A
1 has an immersion cleaning tank 32 containing an organic solvent such as isopropyl alcohol (IPA) 31 which is replaced with water adhering to the surface of the substrate 1. This immersion cleaning tank 32 can be called a replacement cleaning tank. The organic solvent contained in the immersion washing tank 32 is not necessarily limited, but the same organic solvent used in the subsequent steam washing step B is used. As described above, the IPA 31 is used.

The organic solvent is not limited to IPA31, and other organic solvents can be used. For example, when mainly replacing and washing with water, the organic solvent is compatible with water and low in water. An organic solvent having a boiling point is used.

The immersion cleaning tank 32 contains I as a replacement cleaning liquid.
A circulation system 33 for circulating the PA 31 is provided. The circulation system 33 is configured to circulate the IPA 31 from an overflow section 34 provided above the immersion cleaning tank 32 to the immersion cleaning tank 32 via a circulation pump 35.
In addition to the circulation filter 36, a cooling device 37 is interposed in the circulation system 33. This cooling device 37
In the above, cold water is supplied around the cooling coil 38, and the IPA 31 passing through the cooling coil 38 is cooled.

As described above, in the immersion cleaning step A,
When the IPA 31 is circulated in the circulation system 33, the cooling device 37 is used.
Cooling in. Therefore, the IPA 31 accommodated in the immersion cleaning tank 32 is cooled to a room temperature or lower. In this embodiment, the set temperature of the IPA 31 is, for example, 283K.

The steam cleaning step (steam cleaning section) B has a steam cleaning tank 41. An IPA 31 is retained below the inside of the steam cleaning tank 41, and the temperature of the IPA 31 is increased by a heater 42 installed at the bottom of the steam cleaning tank 41, thereby generating steam 43 of the IPA 31. Thus, the IPA steam 43 is contained in the steam cleaning tank 41.
It is constantly occurring.

The heating temperature of the IPA 31 staying below the inside of the steam cleaning tank 41 is controlled to an optimum temperature by, for example, a thermal controller (not shown).
The reduced amount of the IPA 31 is supplied as needed from an IPA supply mechanism linked to a liquid level detection sensor or the like (not shown), and a predetermined amount of the IPA 31 is retained in the steam cleaning tank 41.

In the steam cleaning tank 41, a substrate 21 held in a basket 22 as an object 20 to be cleaned after the immersion cleaning step A is transferred to a predetermined processing position. A waste liquid receiving tray 44 is provided below the position, that is, below the vapor cleaning processing position, for collecting the IPA waste liquid condensed and dropped on the surface of the substrate 21. Waste liquid tray 44
IPA waste liquid collected in the above is the IPA waste liquid recovery and regeneration mechanism D
Sent to The IPA waste liquid recovery / regeneration mechanism D will be described later in detail.

The above-mentioned waste liquid receiving pan 44 has an IP
A cooling coil 45 is provided as cooling means for cooling the A vapor 43, and cold water circulates through the cooling coil 45. The cooling coil 4 provided on the waste liquid tray 44
5. In other words, the cleaning object 2 in the steam cleaning tank 41
Cooling coil 4 provided in the vicinity below the processing position 0
5, the IPA vapor 43 is cooled, so that the IPA vapor 43 generated near the bottom of the steam cleaning tank 41 is drawn toward the cooling coil 45. That is, IPA vapor 4
The flow (steam flow) 3 is controlled by the cooling coil 45,
It is concentrated near the processing position of the article 20 to be cleaned.

A condensation coil 46 is provided above the steam cleaning tank 41.
The condensing coil 46 has a waste liquid receiving pan 4
Cooling water circulates together with the cooling coil 45 on the top 4. The condensing coil 46 cools and condenses the ΔPA vapor 43 rising in the steam cleaning tank 41, thereby suppressing the external discharge of the ΔPA vapor 43. An exhaust duct 47 is provided above the steam cleaning tank 41.

The IPA waste liquid collecting / regenerating mechanism D has a drain tank 49 for collecting the IPA waste liquid collected in the waste liquid receiving tray 44 through a waste liquid collecting pipe 48. The waste liquid collecting pipe 48 is provided with a re-sending pipe 50 for returning the collected IPA waste liquid to the steam cleaning tank 41 as necessary.

The cleaning device of this embodiment has a cooling coil 4
5, the amount of the IPA waste liquid collected in the waste liquid receiving tray 44 increases, so that the IPA waste liquid is not merely discarded, but also temporarily stored in a waste liquid storage tank 52 from a drain tank 49 via a transfer pump 51, and IP from storage tank 52
A is configured to be sent to the A purification / recovery device 53. The regenerated IPA purified by the IPA purification and recovery device 53 is sent to the steam cleaning tank 41 and reused. Waste liquid storage tank 52
Pump 54 so that the waste liquid can be discarded if necessary.
Is connected.

A transfer mechanism C for sequentially transferring the object 20 to be immersed in the immersion cleaning step A and the steam cleaning step B includes a traverse mechanism for transferring between the respective steps, and a predetermined treatment for the object 20 in each step. And an elevating mechanism for transferring and arranging at a position. The position control and the processing time control of the object to be cleaned 20 at each process position and processing position are performed by a sensor and a control unit (not shown).

Next, the operation of the cleaning apparatus of the above embodiment will be described.

First, the substrate 21 is subjected to, for example, a cleaning process in a pre-process, and is housed vertically in a basket 22 with the surface wet with water. In this state, first, the immersion cleaning process A
And is immersed in the IPA 31 in the immersion washing tank 32. In the immersion cleaning tank 32, the water and the like adhering to the surface of the substrate 21 are replaced with the IPA 31, and at the same time, foreign substances and the like existing on the surface of the substrate 21 are removed.

At this time, the I contained in the immersion washing tank 32
Since the PA 31 is cooled by the cooling device 37 when circulating in the circulation system 33 and has a temperature of, for example, about 283 K, the substrate 2 immersed in the IPA 31 in the immersion cleaning tank 32
1 is replaced by cold. The substrate 21 is sent to the next steam cleaning step B in this state. That is, the substrate 21 is sent to the steam cleaning step B while being cooled from room temperature.

The substrate 21 (the cleaning object 20) sent to the steam cleaning step B is transferred to a predetermined processing position in the steam cleaning tank 41. At this time, the IPA 3 in the steam cleaning tank 41
1 is heated by a heater 42 and has a predetermined temperature, for example,
The IPA vapor 43 heated to 353 K or more is supplied to the steam cleaning tank 41.
Is full within.

The IPA vapor 43 basically flows upward from below the vapor cleaning tank 41 and condenses on the surface of the substrate 21 transferred and arranged along the vapor flow. As shown in an enlarged manner, the above-mentioned waste liquid receiving pan 44
Since the IPA vapor 43 is constantly cooled by the cooling coil 45 provided above, in other words, the cooling coil 45 provided near the processing position of the article 20 to be cleaned in the vapor cleaning tank 41, the IPA vapor 43 Is drawn in the direction of the cooling coil 45 as shown by the arrow X in the figure. That is, the IPA vapor flow X is concentrated near the article 20 to be cleaned. In addition, the substrate 21 (the object to be cleaned 20) has been subjected to cold and hot substitution in the immersion cleaning step A,
Since the temperature difference between the PAA 43 and the PA vapor 43 is increased, the IPA vapor flow X can be more efficiently concentrated on the object 20 to be cleaned.

As described above, the cooling coil 45 causes the IPA
The flow of the steam 43 is controlled so that the IPA steam flow X is
By concentrating near 0, the IPA vapor 43 can be efficiently condensed on the surface of the substrate 21. In other words, a large amount of IPA vapor 43 is supplied to the substrate 21 in a short time.
Can be condensed on the surface. The IPA vapor 43 condensed on the surface of the substrate 21 falls together with the moisture and foreign matters adhering to the substrate 21 to perform the final cleaning of the substrate 21 and to be transferred to the outside of the vapor cleaning tank 41. The IPA on the surface of the substrate 21 volatilizes, and the washing and drying steps of the substrate 21 are completed. The dropped IPA waste liquid is sent to a waste liquid receiving tray 44.
Collected at.

As described above, the IPA vapor 43 is applied to the substrate 2.
By efficiently condensing on one surface, the cleaning density (cleanability), cleaning efficiency, and the like can be significantly improved. That is, a higher cleaning quality can be imparted to the substrate 21. Further, if the same level of cleaning quality as that of the related art is obtained, the cleaning time can be reduced. Such improvement in cleaning quality has a great effect on an insulating substrate to which foreign matter such as dust easily adheres due to the influence of static electricity or the like, for example, a glass substrate for a liquid crystal display device which is becoming larger. However, the object to be cleaned in the present invention is not limited to a glass substrate for a liquid crystal display device, but can be applied to various substrates and various industrial parts other than the substrate.

Further, by concentrating the IPA vapor flow X in the vicinity of the object 20 to be cleaned, it is possible to suppress discharge to the outside of the vapor cleaning tank 41. That is, the exhaust duct 47
Of the IPA vapor 43 discharged from the outside to the outside can be suppressed by installing the cooling coil 45, so that the amount of the IPA vapor volatilized and discharged can be reduced, thereby reducing the amount of IPA used, that is, the cleaning cost. It becomes possible to reduce.

As described above, according to the cleaning apparatus of this embodiment, it is possible to provide high-quality cleaning at a low cost to various objects to be cleaned such as a glass substrate for a liquid crystal display. In this embodiment, the cleaning device having the immersion cleaning process A and the steam cleaning process B has been described. Is effective, and it is possible to achieve an improvement in cleaning density (cleanability), cleaning efficiency, and the like due to concentration of the IPA vapor flow.

[0038]

As described above, according to the cleaning apparatus of the first aspect, the organic solvent vapor is concentrated around the object to be cleaned by the cooling means provided near the processing position of the object to be cleaned. Therefore, the cleaning density (cleanability), the cleaning efficiency, etc. can be improved, and the amount of the organic solvent used can be reduced. Further, according to the cleaning apparatus of the second aspect, the concentration of the organic solvent vapor around the object to be cleaned can be more effectively achieved by the cold-temperature replacement during the immersion cleaning of the object to be cleaned.

[Brief description of the drawings]

FIG. 1 is a view showing a schematic configuration of an embodiment of a cleaning apparatus of the present invention.

FIG. 2 is an enlarged view showing a steam cleaning tank portion of the cleaning device shown in FIG.

FIG. 3 is a diagram illustrating a schematic configuration of an example of a conventional cleaning apparatus.

4 is an enlarged view showing a steam cleaning tank portion of the cleaning device shown in FIG. 3;

[Explanation of symbols]

 A: immersion cleaning process B: steam cleaning process C: transfer mechanism D: IPA waste liquid recovery / regeneration mechanism 20: object to be cleaned 31: isopropyl alcohol (IPA) 32: immersion cleaning Tank 37 Cooling device 41 Steam washing tank 42 Heater 43 IPA steam 44 Waste liquid receiving pan 45 Cooling coil

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[Procedure amendment]

[Submission date] September 25, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Claims (2)

[Claims] 1. A cleaning apparatus for condensing vapor of an organic solvent on a surface of an object to be cleaned to wash and dry the object to be cleaned, comprising: means for transferring the object to be cleaned; and the organic solvent retained at a bottom portion. Is heated to generate vapor of the organic solvent, and the object to be cleaned is transferred to a predetermined processing position in a vapor flow of the organic solvent. Cooling means for cooling the vapor of the organic solvent, the cooling means being disposed near a processing position of the cleaning object, wherein the cooling means is configured to concentrate the vapor flow of the organic solvent around the object to be cleaned. A washing device characterized by the above-mentioned. 2. A cleaning apparatus for cleaning an object to be cleaned with an organic solvent, comprising: means for transferring the object to be cleaned; an immersion cleaning tank containing an organic solvent and immersing the object to be cleaned in the organic solvent. An immersion washing unit having a cooling means for cooling the organic solvent accommodated in the immersion washing tank; and heating the organic solvent retained at the bottom to generate vapor of the organic solvent and perform the immersion. The object to be cleaned that has passed through the cleaning unit is disposed and transferred to a predetermined processing position in a vapor flow of the organic solvent, and is disposed near the processing position of the object to be cleaned in the vapor cleaning tank, Cooling means for cooling the vapor of the organic solvent, and a vapor cleaning unit configured to concentrate the vapor flow of the organic solvent around the object to be cleaned by the cooling means. Cleaning equipment.