JP2012122631A - Vapor dryer and vapor drying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent stain from being generated even if impurities are contained in moisture or a solvent adhered to an article to be dried in a vapor dryer, and a vapor drying method.SOLUTION: Drying is performed using the vapor dryer 1 provided with a vapor source 3 for supplying solvent vapor 4A, a drying vessel 2 which has an opening 2a for taking in and taking out the article W to be dried and forms a vapor-filled region V by being filled with the solvent vapor 4A supplied from the vapor source 3 under the opening 2a, a conveying mechanism 7 for conveying the article W to be dried along a conveying passage M covering the inside and outside of the drying vessel 2, and a heating part 8 for heating the article W to be dried conveyed into the drying vessel 2 by the conveying mechanism 7 by a heating source at a temperature higher than a temperature of the solvent vapor 4A and different from the solvent vapor 4A.

Description

  The present invention relates to a steam drying apparatus and a steam drying method.

Conventionally, when cleaning is performed in a manufacturing process of a glass substrate, an optical element, a semiconductor wafer, etc., an object to be cleaned composed of the glass substrate, optical element, semiconductor wafer, etc. is cleaned with a cleaning agent and rinsed with pure water or the like. After that, a drying process is performed in which the rinsed object to be cleaned is dried as the object to be dried. In many cases, for example, a vapor drying apparatus using a solvent such as isopropyl alcohol (IPA) is used in this drying process.
In such a steam drying apparatus, the material to be dried is carried into a solvent vapor atmosphere, the solvent is condensed on the surface of the material to be dried, and the solvent falls with moisture remaining on the material to be dried or volatilizes with moisture. The surface of the object to be dried is dried by using For this reason, if impurities that cannot volatilize with the solvent are contained in the moisture remaining in the solvent or dried object, the impurities are dried while attached to the surface of the dried object, and stains such as stains are formed on the surface of the dried object. The problem that occurs occurs.
In order to cope with such a problem, various steam drying apparatuses and steam drying methods have been proposed.
For example, Patent Document 1 discloses a moisture removal device that removes moisture from a moisture-containing solvent in which moisture in the air is dissolved in a fluorine-based solvent or a fluorine-based solvent mixed with an alcohol or glycol ether-based solvent. A tank for storing the moisture-containing solvent, a heating means for heating the moisture-containing solvent in the tank to around the boiling point of the solvent, a cooling means provided at the upper part of the tank for cooling the moisture and the solvent vapor, and cooling A water removal device is described which comprises a receiving means for receiving a liquid.
Patent Document 2 includes a treatment tank for condensing and drying a vapor of a drying liquid mainly composed of an organic solvent on the surface of an object to be treated after water treatment, and a film that selectively transmits water. The separation membrane module unit is formed, and inside the treatment tank, a steam generation unit for generating the vapor of the drying liquid, a drying space part for arranging the object to be processed, and a vapor of the drying liquid A first receiver that collects the condensate produced by condensation on the surface of the workpiece under the drying space, and a cooling unit that condenses the vapor of the drying liquid above the drying space. And a second receiver that collects the condensate generated by the cooling by the cooling unit below the cooling unit, and the separation membrane module unit receives the condensate from the second receiver. A first flow path for introduction is provided, and the cooling section is condensed in the first flow path. An automatic valve that periodically opens and closes to collect the liquid for a certain period of time is disposed, and the outlet side of the separation membrane module unit is a first for introducing the non-permeated liquid in the membrane into the vapor generating section. A steam drying device is described, characterized in that two flow paths are provided.
Patent Document 3 discloses (1) an IPA tank containing liquid isopropyl alcohol (IPA), (2) a side wall provided around the IPA tank, and (3) a predetermined interval upward from the IPA tank. And (4) heating means provided at least in the lower part of the IPA tank, and (5) supplying preliminarily heated liquid IPA to the liquid IPA in the IPA tank. IPA supply means including preheating means, (6) transport means for taking a silicon wafer in and out of a space defined by the liquid level of the IPA in the IPA tank, the side wall and the cooling pipe, and (7 ) A silicon wafer IPA vapor drying apparatus is described which includes a discharge means for collecting and discharging the mixture of IPA and moisture on the silicon wafer out of the space.

Japanese Patent Laid-Open No. 2003-47802 JP-A-8-152268 JP 2002-367950 A

However, the conventional steam drying apparatus and steam drying method as described above have the following problems.
The techniques described in Patent Documents 1 and 2 are techniques for controlling the concentration of moisture and impurities mixed in the solvent serving as the vapor source, and the technique described in Patent Document 3 prevents a decrease in the vapor concentration, This is a technique for promoting liquid exchange of the surface by bringing the surface of the object to be dried into contact with a sufficient amount of steam.
However, even if these techniques are used, it is difficult to completely remove impurities mixed in the solvent. In addition, since the concentration of impurities that cause stains is extremely low, it is difficult to remove impurities on the surface of the object to be dried in the drying process to such an extent that the generation of stains can be prevented only by these techniques. is there.
Therefore, there is a strong demand for a technique that can suppress the occurrence of stains even if impurities are contained in moisture or solvent adhering to an object to be dried in the drying process.

  The present invention has been made in view of the above problems, and a vapor drying apparatus and vapor drying that are less likely to cause spots even if impurities are contained in moisture or a solvent attached to an object to be dried. It aims to provide a method.

  In order to solve the above problems, a vapor drying apparatus of the present invention has a vapor source for supplying solvent vapor, and an opening for carrying in and out an object to be dried, and the vapor source is provided below the opening. A drying tank that fills the supplied solvent vapor to form a vapor-filled region, a transport mechanism that transports the object to be dried along a transport path extending inside and outside the drying tank, and the transport mechanism to the drying tank. A heating unit configured to heat the carried object to be dried by a heating source that is equal to or higher than the temperature of the solvent vapor and different from the solvent vapor.

  In the steam drying apparatus of the present invention, the heating unit can be provided in the transport mechanism.

  In the steam drying apparatus of the present invention, the heating unit may have a heating adjustment mechanism that adjusts a heating amount.

  Moreover, in the steam drying apparatus of the present invention, the heating unit can be arranged around the transport path of the transport mechanism in the steam filling region.

  Further, in the steam drying apparatus in which the heating unit of the present invention is arranged around the transport path of the transport mechanism, the opening includes a carry-in opening for transporting the material to be dried into the drying tank, and the material to be dried described above. A carry-out opening for carrying out from the drying tank, the carry-in opening and the steam-filled area below the carry-out opening are partitioned, and divided into a carry-in area and a carry-out area, and the heating unit is arranged in the carry-out area. It can be arranged around the transport path of the transport mechanism.

  Further, in the steam drying apparatus of the present invention, the heating unit includes a heat storage member that stores heat of the solvent vapor in the steam filling region, and the heat storage member is transported at least in the transport mechanism by the transport mechanism. And a heat storage member moving mechanism that moves along the path.

  The steam drying method of the present invention includes a steam filling region forming step of filling a solvent tank with a solvent vapor to form a steam filling region, a carrying-in step of bringing an object to be dried into the steam filling region, and the steam filling region. A first drying step in which the material to be dried brought into contact with the solvent vapor is dried, and after the start of the first drying step, the material to be dried is heated by a heating source different from the solvent vapor. A second drying step in which drying is performed by heating at a temperature equal to or higher than the temperature of the solvent vapor; and an unloading step of unloading the object to be dried from the drying tank after the completion of the first and second drying steps. It is a method to prepare.

  According to the steam drying apparatus and the steam drying method of the present invention, after the solvent vapor is condensed on the material to be dried, the drying is performed by heating using a heating source having a temperature equal to or higher than the temperature of the solvent vapor. Even if impurities are contained in the droplets, there is an effect that it is difficult for spots to occur.

It is typical sectional drawing which shows schematic structure of the steam drying apparatus which concerns on the 1st Embodiment of this invention. It is the typical perspective view and top view which show the structure of the to-be-dried object holding jig used for the steam drying apparatus which concerns on the 1st Embodiment of this invention. It is the typical perspective view and top view which show the structure of the conveyance mechanism of the steam drying apparatus which concerns on the 1st Embodiment of this invention. It is sectional drawing when a to-be-dried object holding jig is set to the conveyance mechanism of the steam drying apparatus which concerns on the 1st Embodiment of this invention. It is operation | movement explanatory drawing of the steam drying apparatus which concerns on the 1st Embodiment of this invention. It is a schematic explanatory drawing of the process in which a spot generate | occur | produces. It is typical sectional drawing which shows schematic structure of the steam drying apparatus which concerns on the modification (1st modification) of the 1st Embodiment of this invention. It is typical sectional drawing which shows schematic structure of the vapor drying apparatus which concerns on the 2nd Embodiment of this invention. It is operation | movement explanatory drawing of the steam drying apparatus which concerns on the 2nd Embodiment of this invention. It is typical sectional drawing which shows schematic structure of the steam drying apparatus which concerns on the 3rd Embodiment of this invention. It is a typical top view of the heat storage member used for the steam dryer which concerns on the 3rd Embodiment of this invention. It is operation | movement explanatory drawing of the steam drying apparatus which concerns on the 3rd Embodiment of this invention. It is typical sectional drawing which shows schematic structure of the vapor drying apparatus which concerns on the 4th Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In all the drawings, even if the embodiments are different, the same or corresponding members are denoted by the same reference numerals, and common description is omitted.

[First Embodiment]
A steam drying apparatus according to a first embodiment of the present invention will be described.
FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a steam drying apparatus according to the first embodiment of the present invention. FIGS. 2A and 2B are a schematic perspective view and a plan view, respectively, showing the configuration of an object to be dried used in the steam drying apparatus according to the first embodiment of the present invention. 3A and 3B are a schematic perspective view and a plan view, respectively, showing the configuration of the transport mechanism of the steam drying apparatus according to the first embodiment of the present invention. FIG. 4 is a cross-sectional view of the drying object holding jig set in the transport mechanism of the steam drying apparatus according to the first embodiment of the present invention.

As shown in FIG. 1, the vapor drying apparatus 1 of the present embodiment is an apparatus that uses a solvent vapor 4 </ b> A, which will be described later, as a material to be dried W as a member cleaned by an appropriate cleaning process.
Examples of the material to be dried W include glass substrates, optical elements such as lenses and optical filters, and semiconductor wafers.
Hereinafter, as an example of the object to be dried W, an example in the case of drying a lens for optical equipment will be described. Since many lenses for optical devices are small, a plurality of lenses are accommodated and transported in the object-to-be-dried holding jig 9, and a cleaning process is performed on both the object to be dried W and the object to be dried holding jig 9. A drying process is often performed.
The cleaning process generally includes a plurality of processes, but rinsing is performed with pure water or the like in the final cleaning process. The steam drying apparatus 1 is configured to dry and remove moisture adhering to the surface of the object to be dried W after such rinsing.
In particular, in the optical element manufacturing process, for example, fine particles such as abrasive particles and polished glass may remain slightly even after a plurality of cleaning steps, but the remaining fine particles that do not affect the optical characteristics are allowed. Yes.

Here, an example of the to-be-dried object W and the to-be-dried object holding | maintenance jig | tool 9 used for the following description is demonstrated.
The to-be-dried object W consists of a biconvex lens as shown to Fig.2 (a), (b).
The to-be-dried object holding jig 9 for holding such an object to be dried W is arranged along the facing direction between a frame portion 9a having a rectangular shape in plan view and a pair of inner side surfaces of the frame portion 9a facing each other. And a lattice portion 9b made of a plurality of bar members that are extended and arranged in parallel in a horizontal direction orthogonal to the opposing direction.
The gap in the arrangement direction between the bars of the lattice portion 9b is smaller than the lens outer diameter of the object to be dried W.
For this reason, as shown in FIG. 2B, the object to be dried W is placed from above so that the lens side surface of the object to be dried W is brought into contact with the adjacent bar of the lattice portion 9b. It can be held by the holding jig 9. At this time, the lens surface of each object to be dried W is in a state where its optical axis is directed in the extending direction of the bar.

  As shown in FIG. 1, the schematic configuration of the vapor drying apparatus 1 includes a vapor source 3 that supplies a solvent vapor 4A, and an opening 2a that carries in and out an object to be dried W, and a vapor source below the opening 2a. 3, a drying tank 2 that fills the solvent vapor 4 </ b> A supplied from 3 to form a vapor-filled region V, a transport mechanism 7 that transports the object W to be dried along a transport path M extending inside and outside the drying tank 2, and a transport mechanism 7 includes a heating unit 8 that heats the material to be dried W carried into the drying tank 2 by a heating source that is equal to or higher than the temperature of the solvent vapor 4A and different from the solvent vapor 4A.

  The drying tank 2 of the present embodiment has a bottomed cylindrical shape extending along the vertical direction, an opening 2a is formed in the upper part by the upper end of the drying tank side wall 2c, and a steam source is formed in the lower part. 3 is provided.

In the drying tank 2, a steam cooling pipe 6 that cools the solvent vapor 4 </ b> A formed by the vapor source 3 and confines the solvent vapor 4 </ b> A is disposed between the opening 2 a and the vapor source 3.
In the present embodiment, the steam cooling pipe 6 is made of a metal pipe in which a pipe through which a coolant such as water is circulated is wound in a ring shape or a coil shape, and is arranged along the inner surface of the drying tank side wall 2c of the drying tank 2. Has been. Although not particularly shown, the steam cooling pipe 6 is connected to a chiller device that circulates while controlling the temperature of the refrigerant.
The size of the inner peripheral portion of the steam cooling pipe 6 is set to a size that allows the transport mechanism 7 on which the object to be dried holding jig 9 is mounted to be inserted in the vertical direction.
For this reason, in the central part of the drying tank 2, there is a space in which the object to be dried W held by the object to be dried holding jig 9 can be moved up and down between the upper end of the opening 2a and the steam source 3. It is secured.
The surface temperature of the steam cooling pipe 6 is such that the solvent vapor 4A in contact with the surface condenses, and a low temperature layer is formed on the inner peripheral side of the steam cooling pipe 6 so that the solvent vapor 4A cannot rise through the steam cooling pipe 6. Set to a temperature that can be achieved.
Although not particularly illustrated, a solvent recovery mechanism is provided below the steam cooling pipe 6 to recover the condensed liquid by the solvent vapor 4A heat exchanged on the surface of the steam cooling pipe 6.

Steam source 3, a drying tank 2 of the drying tank bottom 2b on liquid solvent 4 which is stored in the solvent to heat the solvent 4 generates a temperature substantially equal T ₁ of the solvent vapor 4A to the boiling point of the solvent 4 heating Part 5.
Note that the solvent 4 decreases as the components condensed in the steam cooling pipe 6 are recovered. Therefore, a clean solvent 4 is appropriately added from the outside of the drying tank 2 by a supply mechanism (not shown). It is like that.
As a material of the solvent 4, an appropriate organic solvent used for the vapor drying treatment, for example, isopropyl alcohol (IPA), hydrofluorocarbon (HFC), hydrofluoroether (HFE), or the like can be used. In this embodiment, IPA is adopted as an example.

The configuration of the solvent heating unit 5 is not particularly limited as long as the solvent 4 stored on the drying tank bottom surface 2b of the drying tank 2 can be heated to generate the solvent vapor 4A having a temperature necessary for the vapor drying process. For example, a heating body that conducts heat by circulating a heat medium such as oil heated inside can be employed.
Moreover, although the example in case the solvent heating part 5 is installed in the lower surface side of the drying tank bottom face 2b is illustrated in FIG. 1, the installation position of the solvent heating part 5 is not limited to this. For example, it may be immersed in the solvent 4 inside the drying tank 2.
Since the heating temperature of the solvent heating unit 5 is set to IPA as the solvent 4 in this embodiment, the solvent heating unit 5 sets the solvent 4 to a temperature T _{1 in} the vicinity of 82.4 ° C. which is the boiling point of IPA. It can be heated.

  As shown in FIGS. 3A and 3B, the schematic structure of the transport mechanism 7 includes a pair of actuators 7a that move up and down in a vertical direction along a drive guide (not shown), and a vertical direction from the end of each actuator 7a. A suspension arm 7b that extends downward, and a placement frame 7A that is fixed to the lower end portion of each suspension arm 7b and places the object to be dried holding jig 9 from above.

The mounting frame 7A includes a prismatic connecting member 7c that horizontally connects the lower ends of the suspension arms 7b, and a prismatic member that extends in a comb shape from the connecting member 7c to the opposite side of the actuator 7a in the horizontal direction. This is a frame member having a rectangular outer shape in plan view, which is constituted by the lattice frame 7e formed and a prismatic connection member 7d that fixes each end of each lattice frame 7e at a position facing the connection member 7c.
In the mounting frame 7A, the upper surfaces of the connecting members 7c and 7d and the lattice frame 7e are aligned on the same plane so that they can come into close contact with the lower surface of the object to be dried holding jig 9 (see FIG. 4). ).
A plurality of locking pins 7f are provided on the upper surfaces of the connecting members 7c and 7d and the lattice frame 7e constituting the frame outer shape to horizontally lock the side surface of the dried object holding jig 9 placed from above. ing.

The connecting members 7c and 7d and the respective lattice frames 7e are desirably metals that have good heat conduction and that do not contaminate the cleaning tank due to rust or elution. For example, it is formed of a member having a layer structure of stainless steel having high corrosion resistance and aluminum, copper, or an alloy thereof having good thermal conductivity. At least the connection member 7c and the lattice frames 7e are provided with one or more circulation paths 8a for circulating the heat medium H.
As the kind of the heat medium H, a liquid such as water, oil, or a gas such as heated air can be employed.
Both ends of the circulation path 8a are connected to an internal pipe line 8b provided penetrating in each suspension arm 7b. These internal pipe lines 8b are connected to the external pipe 8c at the upper end of the suspension arm 7b. A chiller device (not shown) that circulates while controlling the temperature of the heat medium H is connected to these external pipes 8c.
Temperature T ₂ of the heating medium H, in this embodiment, is set to about 5 ° C. temperature higher than the temperature of the solvent vapor 4A.
For this reason, when the heating medium H is circulated through the circulation path 8a, the temperature of the connecting member 7c and the lattice frame 7e is increased, and the heating source is about 5 ° C. higher than the solvent vapor 4A. Thereby, the to-be-dried object holding jig 9 and the to-be-dried object W mounted on the mounting frame 7A can be heated.
Thus, in this embodiment, the circulation path 8a through which the heat medium H circulates by a chiller device (not shown), the connecting member 7c provided with the circulation path 8a, and the lattice frame 7e constitute the heating unit 8. . Therefore, the present embodiment is an example in which the heating unit 8 is provided in the transport mechanism 7.

Next, operation | movement of the steam drying apparatus 1 is demonstrated centering on the steam drying method which concerns on embodiment of this invention.
FIG. 5 is an operation explanatory diagram of the steam drying apparatus according to the first embodiment of the present invention. FIG. 6 is a schematic explanatory diagram of a process in which a stain is generated. (A1), (b1), (c1), and (d1) are schematic diagrams of the object to be dried W in side view, and (a2), (b2), (c2), and (d2) are schematic diagrams in front view. It is.

  The steam drying method of the present embodiment uses the steam drying apparatus 1 to perform a steam filling region forming step, a carrying-in step, a first drying step, a second drying step, and a carrying-out step with respect to an object to be dried W. This is done in this order.

Steam filling region forming step, is filled with solvent vapor 4A of temperatures T ₁ to the drying chamber 2 is a step of forming a vapor fill region V (see Figure 5 (a)).
In this step, after the solvent 4 is filled on the drying tank bottom surface 2 b in the drying tank 2, a refrigerant is flowed into the steam cooling pipe 6, and a low temperature layer is formed inside the drying tank 2 surrounded by the steam cooling pipe 6. Form.
Next, the solvent 4 is heated by the solvent heating unit 5 to generate a solvent vapor 4 </ b> A having a temperature T ₁ close to the boiling point of the solvent 4. In the present embodiment, the heating temperature of the solvent heating unit 5 is controlled so that the solvent vapor 4A of about 82 ° C. is generated.
The generated solvent vapor 4A rises in the drying tank 2, is cooled by the low temperature layer formed by the steam cooling pipe 6 and descends, and fills the drying tank 2 while repeating convection.
Of the solvent vapor 4A, the liquid condensed by heat exchange on the surface of the vapor cooling pipe 6 is recovered by a solvent recovery mechanism (not shown).
Since the solvent vapor 4A can not be elevated above the steam condenser 6, a state of forming a vapor surface S ₂ in the vicinity of the steam cooling pipe 6, trapped within the drying chamber 2 Become. As a result, a vapor full region V is formed between the solvent liquid surface S ₁ and the vapor surface S ₂ of the solvent 4.
With the above, the steam filling region forming step is completed.

Next, a carrying-in process is performed. This step is a step of bringing the material to be dried W into the steam filling region V.
First, the object to be dried W is placed on the object to be dried holding jig 9 through the cleaning process. The same applies to the following steps.
In this step, the transport mechanism 7 is kept on standby so that the mounting frame 7A is positioned above the center of the opening 2a of the drying tank 2. At this time, the supply or circulation of the heat medium H is stopped. Thus, heating by the heating unit 8 is stopped or suppressed, not performed heating at least a temperature above T _1.
The to-be-dried object W after the cleaning process is transferred onto the mounting frame 7A by a transfer robot (not shown) together with the to-be-dried object holding jig 9 (see FIG. 4).
After transfer, immediately drives the actuator 7a of the transport mechanism 7, a loading frame 7A is lowered as shown in FIG. 5 (a), the vapor filled space through the vapor surface S ₂ as shown in FIG. 5 (b) The material to be dried W and the material to be dried holding jig 9 are carried into the vapor-filled region V.
Thus, the carry-in process is completed.

While the material to be dried W is carried into the vapor filling region V, the first drying process is started.
This step is a step of drying by bringing the material to be dried W carried into the vapor filling region V into contact with the solvent vapor 4A.
In the first drying step in the present embodiment, the position is not particularly limited as long as the object to be dried W is in the vapor full region V. For this reason, the conveyance mechanism 7 may be temporarily stopped to fix the position of the object to be dried W, or the present process may be performed while the object to be dried W is moved in the vapor filling region V by driving the conveyance mechanism 7. You may go. In terms of drying efficiency, it is preferable to perform this step while moving the inside of the vapor-filled region V so that the solvent vapor 4A can easily come into contact with the surface of the article W to be dried.
In the present embodiment, the moving path of the vapor fill region V, as shown in FIG. 5 (b), (c) , along the conveying path M, solvent liquid vapor fill region V from the vapor surface S ₂ side after lowering to the vicinity of the surface S _1, it employs a moving path of vertical reciprocating back rises towards the vapor surface S _2.

Since the to-be-dried object W carried into the vapor | steam filling area | region V is low temperature compared with the solvent vapor | steam 4A, the condensation amount of the solvent vapor | steam 4A in the surface of the to-be-dried object W increases. The condensed solvent vapor 4A takes in moisture on the surface of the material to be dried W and liquefies, and when it becomes a large droplet, it falls together with the taken-in moisture.
Since the object to be dried W is placed on the object to be dried holding jig 9 so that the optical axis of the lens surface to be cleaned faces in the horizontal direction, the droplets on the surface drop downward along the lens surface. It moves and falls from the lower side of the lens surface through a gap between the lattice portions 9b of the object to be dried holding jig 9.
Since such falling droplets fall in a state including moisture on the surface of the object to be dried W and impurity particles contained in the moisture and the solvent vapor 4A, moisture is removed in this step. There is an action of drying and an action of cleaning to remove impurity particles.

However, as the drying and removal of moisture proceeds and heat exchange between the object to be dried W and the solvent vapor 4A proceeds, the number of droplets falling from the surface of the object to be dried W decreases, and the surface of the object to be dried W is reduced by surface tension. The amount of evaporation from the droplet surface adhering to the surface increases.
The inventor diligently studied the drying process by evaporation from the droplet surface, and found that the generation of stains was closely related to the behavior of the impurity particles in the drying process, resulting in the present invention. .
In the following, the process of occurrence of spots found by the inventor will be described by simplifying the observation results.

As shown in FIG. 6 (a1), the lower end portion of the material to be dried W, and droplets D ₁ by surface tension are adhered. Droplet D ₁ is either a water alone, or a condensed droplets of the solvent vapor 4A incorporating water does not matter.
Observation of the droplet D _1, as shown in FIG. 6 (a2), impurity particles P contained in the droplet D ₁ is constantly moved by the molecular movement of the periphery of the droplet D _1, the spacing between the impurity particles P Tend to open up. Therefore, as a whole, and the droplet D ₁ moves toward the contact boundary between the material to be dried W surface (see curve L _1).
The impurity particles P that have reached the contact boundary L ₁ are partially affected by the molecular motion of the droplet D ₁ by contacting the surface of the material to be dried W or aggregating with other impurity particles P. becomes Nikuku, it stops at a position along the contact boundary L _1.
In this way, impurity particles P tend to continue to concentrate on the time contact boundary L _1.

On the other hand, at the same time it moved to such an impurity particles P, from the surface of the droplet D ₁ results evaporation continues, as shown in FIG. 6 (b1), (b2) , the droplets D ₁ volume is reduced the flattened droplet D _2. At this time, contact boundary L ₂ is substantially the same position as the contact boundary L _1.
Since the diameter of the droplet D ₂ is about to be reduced by the surface tension, when a certain amount of time elapses, the contact boundary L ₂ sharply reaches the position of the curve L ₃ as shown in FIGS. 6 (c1) and (c2). Go and changes in liquid droplet D ₃ the contact area between the material to be dried W is reduced.
Along with this, at a position spaced from the contact boundary L _2, contact boundary L ₃ between the droplet D ₃ and the material to be dried W is formed. On the other hand, since the impurity particles P on the contact boundary L ₂ are left behind on the surface of the object to be dried W, they adhere to the object to be dried W in the state of being aligned in the vicinity of the curve L ₂ , and the substantially linear spot P _S is formed.
In the droplet D _3, for the similar process is repeated, if the droplet D ₃ dried, as shown in FIG. 6 (d1), (d2) , the contact boundary L ₃ is formed position, substantially linear stain portion P _S is formed.

In this way, when the stains at the time of drying are viewed finely, the impurity particles P in the droplet move near the contact boundary between the material to be dried W and the droplet attached to the material to be dried W, resulting in unevenness. it is considered to be a collection of integrated and stain section P _S.
For this reason, even if the total amount of the impurity particles P is very small, it can be seen that a significant stain mark formed by the aggregation of the impurity particles P is formed, resulting in a stain as a whole.

In order to suppress the stains formed in this way, in the present embodiment, the second drying step is performed in parallel with the first drying step when a certain time has elapsed after the start of the first drying step.
This step is a step of drying the heated object W at a temperature equal to or higher than the temperature of the solvent vapor 4A by a heating source different from the solvent vapor 4A after the start of the first drying step.
In the present embodiment, by circulating a heat medium H of temperature T ₂ in the circulation path 8a of the heating unit 8, and heated the grid frame 7e or the like temperature T _2. Thereby, heat is transferred to the object to be dried holding jig 9 in contact with the lattice frame 7e and the like, and the object to be dried W is heated, and the ambient temperature in the vicinity of the object to be dried W also rises.

As a result, the droplets adhering to the material to be dried W are heated. For this reason, the molecular motion of the droplet becomes active and the surface tension of the droplet decreases. Evaporation proceeds rapidly with a large surface area of the droplet.
Therefore, the impurity particles P in the dried droplets are not sufficiently accumulated at the contact boundary, but are fixed to the object to be dried W at positions separated from each other. In addition, since the surface tension of the droplet is reduced, the stepwise movement of the contact boundary as shown in FIG. 6 (c2) hardly occurs during the drying process.
For this reason, even if the impurity particles P in the droplets remain on the material to be dried W, they are not easily stained because they are dispersed within the initial droplet area.
The impurity particles P dispersed in this way not only do not deteriorate in appearance, but also, for example, when the transmission or reflection characteristics of a light beam having a much larger diameter than the impurity particles P becomes a problem like an optical element. It is not a functional defect.

This step may be started at an appropriate timing at which the stain is less likely to remain depending on the to-be-dried object W and the heat capacity of the to-be-dried object holding jig 9.
As described above, since the liquid droplets falling from the surface of the object to be dried W also have the effect of removing the impurity particles P as well as the drying action, the object to be dried W condenses on the surface of the object to be dried W and drops. It is preferable to start the period in which the droplets are likely to fall without starting the second drying step after the change of the total amount of the impurity particles P on the material to be dried W is reduced due to the drop of the droplets. .
However, depending on the heat capacity of the material to be dried W and the material to be dried holding jig 9, there is a time difference between the timing at which the heating unit 8 reaches a certain temperature and the timing at which the droplets on the material to be dried W are heated. Arise. For this reason, it is preferable to set an appropriate start timing, for example, by conducting an experiment.

After the replacement of the liquid on the surface of the article to be dried W is completed, the actuator 7a of the transport mechanism 7 is driven to raise the placement frame 7A. When material to be dried W is moved upward vapor surface S _2, to stop or suppress the circulation of the heat medium H of the heating unit 8 stops the heating by temperature T _2.
Thus, the first and second drying steps are completed.
Thereafter, an unloading process is performed. In this step, the actuator 7a is continuously driven to raise the mounting frame 7A, and the object to be dried W and the object to be dried holding jig 9 are carried out upward from the opening 2a. This is the end of the unloading process.

  Thus, according to the steam drying apparatus 1 and the steam drying method using the steam drying apparatus 1, after the solvent vapor 4A is condensed on the material W to be dried, the heating unit 8 heats the solvent vapor 4A at a temperature equal to or higher than the temperature of the solvent vapor 4A. And dry. As a result, the surface tension of the droplets adhering to the surface of the object to be dried W is reduced, and drying proceeds rapidly before the impurity particles P in the droplets move to the contact boundary with the object to be dried W. For this reason, even if impurities are contained in the moisture or the solvent vapor 4A attached in the cleaning process, it is difficult to cause a stain.

[First Modification]
Next, a modified example (first modified example) of the first embodiment will be described.
FIG. 7 is a schematic cross-sectional view showing a schematic configuration of a steam drying apparatus according to a modification (first modification) of the first embodiment of the present invention.

As shown in FIG. 7, the steam drying device 11 of the present modification includes a heating unit 18 instead of the heating unit 8 of the steam drying device 1 of the first embodiment. Hereinafter, a description will be given centering on differences from the first embodiment.
The heating unit 18 includes a cooling pipe 10 connected to a chiller device that circulates the refrigerant such as water by controlling the temperature in parallel with the circulation path 8a of the heating unit 8 inside the lattice frame 7e and the connecting member 7c. It is provided.

According to the steam drying apparatus 11, the material to be dried W can be dried by substantially the same steam drying method as in the first embodiment.
In this modification, heat transfer from the circulation path 8a is suppressed by increasing the flow rate of the refrigerant circulating through the cooling pipe 10 until the second drying step is started. Thus, the cooling pipe 10 is an example of a heating adjustment mechanism that adjusts the heating amount in the heating unit 18.
Thereby, compared with the said 1st Embodiment, the temperature rise of the to-be-dried object W and the to-be-dried object holding jig 9 can be reduced.
As a result, in the first drying step, the temperature difference between the solvent vapor 4A and the material to be dried W can be made larger than that in the first embodiment, so that the solvent vapor 4A It tends to condense on the surface. Therefore, prior to the second drying step, moisture and impurity particles P on the material to be dried W can be more efficiently removed.
Next, in the second drying step, the circulation of the refrigerant in the cooling pipe 10 is stopped, and the temperature of the heating unit 18 is rapidly increased to the temperature of the heating medium H. Thereby, rapid heating of the to-be-dried object W is attained. For this reason, since the drying of the droplet on the to-be-dried object W also progresses rapidly, it becomes difficult to form a stain.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
FIG. 8 is a schematic cross-sectional view showing a schematic configuration of a steam drying apparatus according to the second embodiment of the present invention. FIGS. 9A, 9B and 9C are operation explanatory views of the steam drying apparatus according to the second embodiment of the present invention.

  As shown in FIG. 8, the steam drying device 21 of the present embodiment includes a transport mechanism 27 and a heating unit 28 instead of the transport mechanism 7 and the heating unit 8 of the steam drying device 1 of the first embodiment. Hereinafter, a description will be given centering on differences from the first embodiment.

The transport mechanism 27 is obtained by deleting the circulation path 8a, the internal pipe line 8b, and the external pipe 8c from the transport mechanism 7.
Heating unit 28 is a heat source for heating the material to be dried W at a temperature T _2, in this embodiment, formed in an annular or coiled inside heating medium H of the annular heat dissipating member 28a is circulated heated The structure provided with the pipe | tube 28b is employ | adopted.
The heating unit 28 is installed along the inner surface of the drying tank side wall 2 c of the drying tank 2 below the steam cooling pipe 6. However, the lower surface of the heating unit 28 and the solvent liquid surface S ₁ are separated by a distance at which at least the object to be dried W and the object to be dried holding jig 9 can be disposed.
Although not particularly shown, a chiller device that circulates while controlling the temperature of the heating medium H is connected to the heating pipe 28b.
The size of the opening inside the radiator 28a is set to a size that allows the transport mechanism 7 on which the object to be dried holding jig 9 is mounted to be inserted in the vertical direction.
For this reason, in the center part of the drying tank 2, there is a space in which the object to be dried W held by the object to be dried holding jig 9 can be moved up and down between the opening 2a at the upper end and the steam source 3. It is secured.
Although not particularly shown, the solvent vapor 4A cooled by the vapor cooling pipe 6 can be lowered between the heating unit 28 and the drying vessel side wall 2c of the drying vessel 2 and can easily return to the lower layer region. Thus, the flow path along the vertical direction is secured.

According to the steam drying device 21, the material to be dried W can be dried in substantially the same manner as the steam drying method of the first embodiment.
In the present embodiment, in the steam-filled region formation step, after the steam-filled region V is formed, the heat pipe 28b to circulate the heat medium H of temperature T _2, the heat radiating member 28a temperature T ₂ the solvent vapor 4A in the vicinity of Heat to. Since the temperature T _{2 of the} heating medium H is higher than the temperature T ₁ of the solvent vapor 4 A formed by the vapor source 3, the temperature of the solvent vapor 4 A in the vicinity of the heating unit 28 rises and the inner circumference of the heating unit 28 is increased. A layer region having a relatively high temperature is formed in the side region.
For this reason, as shown in FIG. 8, the vapor-filled region V has a temperature in the vicinity of the lower layer region V ₁ , the temperature T ₁ between the solvent liquid level S ₁ and the vicinity of the lower portion of the heating unit 28, in the vicinity of the heating unit 28. It is divided into an intermediate layer region V ₂ defined as T ₂ and an upper layer region V ₃ in which the temperature varies from T _{2 to} T ₁ between the vicinity of the upper portion of the heating unit 28 and the vapor surface S ₂ .

In the carrying-in process of this embodiment, as shown in FIG. 9A, the to-be-dried object W and the to-be-dried object holding jig 9 are carried into the steam filling region V as in the carrying-in process of the first embodiment. At this time, the moving speed of the transport mechanism 27 is controlled so that the temperature of the object to be dried W and the object to be dried holding jig 9 is suppressed when passing through the upper layer region V ₃ and the middle layer region V _{2. 1} to move quickly.
Then, upon reaching the lower region V _1, as shown in FIG. 9 (b), switch to the movement by the velocity v ₂ is slower than the speed v _1. However, the speed v ₂ includes stopping and turning, and | v ₁ |> | v ₂ | ≧ 0.
Thus, the carry-in process is completed.

When material to be dried W reaches the lower region V _1, the material to be dried W occurs heat exchange with the solvent vapor 4A of temperatures T ₁ in the region below V _1, the first drying step is started.

In the present embodiment, when it is time to start the second drying step similar to that in the first embodiment, as shown in FIG. 9C, the transport mechanism 27 causes the material to be dried W and the material to be dried. holding jig 9 is raised to move the middle region V ₂ in. Then, once it stopped in the middle region _{V 2.} By this movement, the first drying process is completed and the second drying process is started.
In the second drying step of the present embodiment, the heat of the heating unit 28 is transmitted to the object to be dried W, whereby the object to be dried W is heated. Although the heat transferred is included also radiant heat from the heating unit 28, the contribution of the heat exchange by contact with a solvent vapor 4A which is heated to temperature T ₂ in the middle region V ₂ is considered large.

The solvent vapor 4 </ b> A whose temperature has been lowered by heat exchange with the object to be dried W and the object to be dried holding jig 9 descends to the lower layer region V <b> _1, and therefore around the object to be dried W and the object to be dried holding jig 9. , the solvent vapor 4A which is heated to temperature T ₂ by heat exchange with the heat radiating member 28a is sequentially supplied to the vicinity of the material to be dried W and the object to be dried holding jig 9, the material to be dried W and the object to be dried while holding jig 9 are positioned in the middle region V _2, drying is continued by such temperature T _2. Thereby, the droplet adhering to the surface of the to-be-dried object W in the 1st drying process is dried rapidly, and generation | occurrence | production of a spot is suppressed.
Similar to the first embodiment, when the droplets on the surface of the object to be dried W are dried, the second drying process is terminated.

Next, in the unloading step, in the same manner as in the first embodiment, by driving the transport mechanism 27, raises the material to be dried W and the object to be dried holding jig 9, and moves in the upper region V ₃ from passing through the steam surface S _2, it is carried out from the opening 2a to the outside of the drying vessel 2.

  As described above, according to the steam drying apparatus 21 and the steam drying method using the steam drying apparatus 21, the solvent vapor 4A is condensed on the material to be dried W by the heating unit 28, as in the first embodiment. Since drying is performed by heating at a temperature equal to or higher than the temperature of the solvent vapor 4A, even if impurities are contained in the moisture adhering to the cleaning process or the solvent vapor 4A, it is difficult for spots to occur.

[Third Embodiment]
Next, a third embodiment of the present invention will be described.
FIG. 10 is a schematic cross-sectional view showing a schematic configuration of a steam drying apparatus according to the third embodiment of the present invention. FIG. 11 is a schematic plan view of a heat storage member used in the steam drying apparatus according to the third embodiment of the present invention. 12 (a), (b), (c), and (d) are operation explanatory views of the steam drying apparatus according to the third embodiment of the present invention.

  As shown in FIG. 10, the steam drying device 31 of this embodiment includes a transport mechanism 27 of the second embodiment instead of the transport mechanism 7 of the steam drying device 1 of the first embodiment. Moreover, it replaces with the heating part 8 of the steam drying apparatus 1 of the said 1st Embodiment, and is equipped with the heat storage plate 38 (heat storage member). Hereinafter, the points different from the first and second embodiments will be mainly described.

The heat storage plate 38 is a member for storing the heat of the solvent vapor 4 </ b> A inside the vapor filling region V. In this embodiment, as shown in FIGS. 10 and 11, it is a metal block member having an area where the object to be dried holding jig 9 can be placed. The upper surface of the heat storage plate 38 is aligned in a plane so that it can come into close contact with the lower surface of the mounting frame 7A.
In the thickness direction of the heat storage plate 38, the solvent vapor 4 </ b> A can flow up and down, and a large number of through holes 38 a are arranged in a grid to guide the droplets falling from the material to be dried W or the like downward. ing. These through holes 38 a also have a function of increasing the surface area of the heat storage plate 38.
The outer shape and material of the heat storage plate 38 have a heat capacity such that the object to be dried W and the object to be dried holding jig 9 can be heated at the temperature T ₁ during the second drying step in the steam filling region V. Is set to be

The heat storage plate 38 is connected to a heat storage member moving mechanism 30 that moves the heat storage plate 38 along at least the transport path M of the transport mechanism 27 in the steam filling region V.
The heat storage member moving mechanism 30 of the present embodiment includes a pair of actuators 30a that move up and down in a vertical direction along a drive guide (not shown), and a suspension arm 30b that extends vertically downward from the end of each actuator 30a. The lower end of each suspension arm 30b is fixed to the upper surface of the heat storage plate 38.

According to the steam drying device 31, the material to be dried W can be dried in substantially the same manner as the steam drying method of the first embodiment.
In the steam filling region forming step of the present embodiment, as shown in FIG. 12A, the heat storage plate 38 is disposed at a position close to the steam source 3 by the heat storage member moving mechanism 30.
Thus, the heat storage plate 38 and the solvent vapor 4A to exchange heat between the steam-filled region V is formed, the temperature of the heat storage plate 38 is raised to a temperature T _1. In addition, since the heat storage plate 38 has many through holes 38a, the solvent vapor 4A can be convected through the through holes 38a. Further, when the solvent vapor 4A convects, the heat exchange between the heat storage plate 38 and the solvent vapor 4A is promoted by passing through the through hole 38a.
When the heat storage plate 38 reaches thermal equilibrium with the solvent vapor 4A in the vapor filling region V, the vapor filling region forming process is terminated and a carrying-in process is performed.

In the carrying-in process of the present embodiment, the carrying mechanism 27 is used to carry the material to be dried W and the material to be dried holding jig 9 into the vapor filling region V in the same manner as in the first embodiment.
As in the first embodiment, when the object to be dried W and the object to be dried holding jig 9 are carried into the vapor full region V, the first drying process is started.

In the first drying process of the present embodiment, the object to be dried W and the object to be dried holding jig 9 may be moved within the steam-filled region V or stopped, as in the first embodiment. It may be. However, as shown in FIG. 12 (b), it is moved or stopped in a region spaced upward from the heat storage plate 38. This is for avoiding contact with the to-be-dried object W and the to-be-dried object holding jig 9, and the heat storage plate 38, thereby making them less susceptible to thermal influences.
Therefore, in the first drying step, in the vicinity of the object to be dried W and the object to be dried holding jig 9, there is a temperature difference between the object to be dried W and the object to be dried holding jig 9 and the solvent vapor 4A at the time of carry-in. Correspondingly, the temperature drop region slightly temperatures than temperatures T ₁ drops are formed.

Next, in this embodiment, when the timing for starting the second drying step similar to that in the first embodiment is reached, the heat storage member moving mechanism 30 or the transport mechanism 27 is used as shown in FIG. Then, the vertical position of the mounting frame 7A and the heat storage plate 38 is adjusted to bring the upper surface of the heat storage plate 38 into contact with the lower surface of the mounting frame 7A.
Thus, heat conduction occurs to the cold of the loading frame 7A than temperatures T ₁ for the heat storage plate 38 is carried in from the outside of the drying chamber 2 of temperatures T _1, the material to be dried held Osamu the loading frame 7A abuts The object to be dried holding jig 9 is heated through the tool 9.
As described above, the solvent vapor 4A in the vicinity of the material to be dried W and the object to be dried holding jig 9, by heat exchange, for forming the temperature drop region, heat storage heat accumulated and kept temperatures T ₁ The plate 38 is a heating source having a higher temperature than the solvent vapor 4A around the object to be dried W.
Therefore, the heat storage plate 38 serves as a heating source in which the object to be dried W carried into the drying tank 2 by the transport mechanism 27 has a constant temperature T ₁ and is spaced apart from the steam source 3. Together with the heat storage member moving mechanism 30 that brings the plate 38 into contact with the mounting frame 7A, a heating unit that performs the second drying step is configured.
Thus, the 2nd drying process of this embodiment is started.

In the second drying step of the present embodiment, the heat storage member moving mechanism 30 and the transport mechanism 27 while keeping such a contact state, to move toward the vapor surface S _2.
And as shown in FIG.12 (d), the to-be-dried object W and the to-be-dried object holding jig 9 from the vapor | steam filling area | region V according to the timing which the 2nd drying process similar to the said 1st Embodiment complete | finishes. To unload. Thus, the second drying process is completed.

Next, the unloading process of this embodiment is performed. In this step, the transport mechanism 27 continues to rise, thereby carrying the object to be dried W and the object to be dried holding jig 9 out of the drying tank 2 as in the first and second embodiments.
On the other hand, the heat storage member moving mechanism 30 lowers the heat storage plate 38 to release the contact with the placement frame 7A. Thereby, since the heat conduction from the heat storage plate 38 stops, the heat storage of the heat storage plate 38 is restarted.
Then, the descent continues further, and the heat storage plate 38 is positioned at the descent position in the steam filling region forming step. Thereby, drying of the other to-be-dried material W can be performed continuously by repeating said carrying-in process and below.

As described above, according to the steam drying device 31 and the steam drying method using the steam drying device 31, the solvent vapor 4A is condensed on the material to be dried W by the heat storage plate 38, as in the first embodiment. for drying by heating at a temperature T _1, be included impurities moisture and solvent vapor 4A deposited in the cleaning step, the stain does not easily occur.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described.
FIG. 13 is a schematic cross-sectional view showing a schematic configuration of a steam drying apparatus according to the fourth embodiment of the present invention.

  The steam drying apparatus 41 of the present embodiment is an apparatus that is suitable for holding the objects to be dried W in the plurality of objects to be dried holding jigs 9 and drying them continuously, as shown in FIG. Instead of the drying tank 2, the transport mechanism 7, and the heating unit 8 of the steam drying apparatus 1 of the first embodiment, a drying tank 42, a transport mechanism 47, and a heating unit 48 are provided. Hereinafter, a description will be given centering on differences from the first embodiment.

The drying tank 42 has a bottomed cylindrical shape extending in the vertical direction, and a partition wall 42a is installed on the inner upper side of the drying tank side wall 42c, and the drying tank side wall 42c and the partition wall 42a are provided on the upper part. Two surrounded openings 42A and 42B are formed.
Below the openings 42A and 42B, cylindrical portions 40A and 40B extending in the vertical direction surrounded by the drying tank side wall 42c and the partition wall 42a up to the lower end of the partition wall 42a are formed.
The sizes of the openings 42A, 42B and the cylindrical portions 40A, 40B are wider than the size of the object to be dried holding jig 9 holding the object W to be dried, and the object to be dried holding the object W is held. A space in which the dry matter holding jig 9 can be conveyed in the horizontal direction is formed.
For this reason, in the inside of the drying tank 2, the material to be dried W and the material to be dried holding jig 9 are introduced into the opening 42 </ b> A from vertically above and moved vertically downward, and then the partition wall 42 a and the drying tank bottom surface 42 b. A substantially U-shaped space that can be moved vertically downward from the opening 42B is formed.

  In addition, a vapor source 3 similar to that in the first embodiment is provided in the lower part of the drying tank 42. The arrangement position of the steam source 3 is the same positional relationship with respect to the drying tank bottom surface 42b of the drying tank 42 as to the drying tank bottom surface 2b in the first embodiment.

The opening 42A of the present embodiment constitutes a carry-in opening for carrying the material to be dried W into the drying tank 42, and the opening 42B constitutes a carry-out opening for carrying the material to be dried W from the drying tank 42. Yes.
In the cylindrical portion 40A (40B), a vapor cooling pipe 46A (46B) for cooling the solvent vapor 4A formed by the vapor source 3 and confining the solvent vapor 4A is disposed below the opening 42A (42B). ing.
Similarly to the steam cooling pipe 6 of the first embodiment, the steam cooling pipes 46A and 46B are made of metal pipes in which a pipe through which a refrigerant such as water is circulated is wound in an annular shape or a coil shape, respectively. It arrange | positions along the inner surface of 40-shaped part 40A, 40B. Although not particularly shown, a chiller device that circulates while controlling the temperature of the refrigerant is connected to the steam cooling pipes 46A and 46B.
The openings formed inside the steam cooling pipes 46A and 46B are in a state in which the object to be dried holding jig 9 holding the object to be dried W is held by the upper and lower conveying mechanisms 47A and 47B of the conveying mechanism 47 described later. It is provided in a size that allows it to advance and retract in the vertical direction.
The surface temperatures of the steam cooling pipes 46A and 46B are set in the same manner as the steam cooling pipe 6 of the first embodiment. Further, similarly to the first embodiment, a solvent recovery mechanism (not shown) is provided below the steam cooling pipes 46A and 46B.
In the present embodiment, the installation height of the steam cooling pipe 46B is set to be higher than the installation height of the steam cooling pipe 46A.

Conveying mechanism 47 is detachably gripping the material to be dried holding jig 9, the vertical transport mechanism 47A which passes through the inside of the opening portion 42A and the steam condenser 6A to lift along a conveying path M _A vertically extending And the to-be-dried object holding jig 9 is placed in the shape of a moving belt, and extends in a horizontal direction from a certain position below the opening 42A to a certain position below the opening 42B through the partition 42a. a belt conveying mechanism 47C for conveying along the conveying path M _C, conveying path M which detachably grip the material to be dried holding jig 9, extending in the vertical direction through the inside of the opening portion 42A and the steam condenser 6A _And a vertical transport mechanism 47B that moves up and down along _B.
The vertical transport mechanisms 47A and 47B are configured such that, for example, a transport arm including a hand unit that grips and releases the object to be dried holding jig 9 at the lower end is moved up and down by an actuator similar to the actuator 7a in the first embodiment. Can be adopted.

With such a configuration, the article to be dried W held by the article to be dried holding jig 9 is moved up and down between the openings 42A and 42B and the belt transport mechanism 47C at the center of the cylindrical portions 40A and 40B. conveying path M _a space that can be moved is by upper and lower transport mechanism 47A, _47, is secured around the M _B.

Heating unit 48, similarly to the heating portion 28 of the second embodiment is intended to heat the material to be dried W and the object to be dried holding jig 9 in the heat source temperature T _2, the tubular portion 40B In FIG. 4, the steam cooling pipe 46B and the belt conveyance mechanism 47C are provided.
Construction of the heating unit 48, in this embodiment, the metal pipe having the same structure as the steam condenser 46B as heat radiator, the chiller unit (not shown) inside the metal pipe, which is temperature controlled at temperature T ₂ heat The medium H is circulated.

According to the steam drying device 41, the material to be dried W can be dried in substantially the same manner as the steam drying method of the first embodiment.
In the steam filling region forming step of the present embodiment, first, the steam filling region V is formed. In the present embodiment, steam surfaces S _A and S _B having different heights are formed by the steam cooling pipes 46A and 46B, respectively. Is different.
After the steam filling region V is formed, the heat pipe 48 is circulated heat medium H of a temperature T _2, to heat the solvent vapor 4A in the vicinity of the metal pipe is heat radiator to a temperature T _2. Thereby, similarly to the second embodiment, a layer region having a relatively high temperature is formed in the region on the inner peripheral side of the heating unit 48.
For this reason, as shown in FIG. 13, the vapor-filled region V in the tubular portion 40B is a lower layer region V ₁ that is set to a temperature T ₁ between the lower end of the tubular portion 40B and the vicinity of the lower portion of the heating unit 48, temperature between the middle region _{V 2} is the temperature _{T 2} in the vicinity, and from the vicinity of the upper portion of the heating unit 48 until the vapor surface _{S a} of the heating section 48 is divided into an upper region _{V 3} which vary from _T 2 through T _1.

In the carry-in process of the present embodiment, the object to be dried W and the object to be dried holding jig 9 are gripped by the vertical transport mechanism 47A, and the object to be dried W and the object to be dried holding jig 9 are held from above the opening 42A. Carry in.
When the object to be dried W and the object to be dried holding jig 9 are carried into the vapor filling region V, the first drying process is started.

In a first drying step of the present embodiment, while the material to be dried W and the object to be dried holding jig 9 is moved in a steam filled region V, followed by drying by solvent vapor 4A temperature T _1. The drying process at this time is the same as that described in the first embodiment.
The movement route in this step will be described. The material to be dried W and vertical transportation mechanism 47A of the material to be dried holding jig 9 moves from the vapor surface S _A on the belt conveyor mechanism 47C, subjected to the gripping releasing the material to be dried holding jig 9 on the belt conveying mechanism 47C Then, the object to be dried W and the object to be dried holding jig 9 are transferred onto the belt conveyance mechanism 47C.
The belt conveyance mechanism 47C conveys the transferred article W and the article to be dried holding jig 9 to a position below the cylindrical portion 40B. At a position below the cylindrical portion 40B, the vertical transport mechanism 47B is lowered in advance, so that the object to be dried holding jig 9 can be gripped.
The vertical conveyance mechanism 47B that holds the object to be dried holding jig 9 moves the object to be dried W and the object to be dried holding jig 9 vertically upward. In this movement, while the material to be dried W and the object to be dried holding jig 9 is moved the lower region V ₁ was, first drying.

Material to be dried W and the object to be dried holding jig 9 reaches the middle region V _2, to stop the vertical transport mechanism 47B, to start a second drying step. That is, the drying in the same manner as in the second drying step in the middle region V ₂ in the second embodiment.
Similar to the first embodiment, when the droplets on the surface of the object to be dried W are dried, the second drying process is terminated.

Next, in the unloading step, by driving the vertical transportation mechanism 47B, to raise the material to be dried W and the object to be dried holding jig 9, Move to the upper region V _3, passes through the vapor side S _B Then, it is carried out of the drying tank 42 from the opening 42B.

  In the above description, the operation of one object to be dried W and the object to be dried holding jig 9 has been described. However, the upper and lower transport mechanism 47B that has been lifted upward and moved to the outside of the drying tank 2 is released. Is lowered again, the other dried object W and the dried object holding jig 9 can be subsequently introduced and the above steps can be repeated. For this reason, according to the steam drying apparatus 41, the to-be-dried object W mounted in the several to-be-dried object holding jig 9 is intermittently conveyed in one drying tank 42, and is continuously steam-dried. It can be performed.

Thus, according to the steam drying apparatus 41 and the steam drying method using the steam drying apparatus 41, the solvent vapor 4 </ b> A is condensed on the material to be dried W by the heating unit 48, as in the first embodiment. Since drying is performed by heating at a temperature equal to or higher than the temperature of the solvent vapor 4A, even if impurities are contained in the moisture adhering to the cleaning process or the solvent vapor 4A, it is difficult for spots to occur.
Although this embodiment is an example in the case of providing a heating part formed by a layer region having a relatively high temperature T ₂ in the vapor filling region V, as in the second embodiment, In the present embodiment, the heating unit 48 is disposed only on the carry-out path in the tubular part 40B separated from the tubular part 40A where the carry-in path is provided by the partition wall 42. For this reason, in the carry-in route, the object to be dried W and the object to be dried holding jig 9 are not heated by the influence of the heating unit, and the solvent vapor 4A is efficiently condensed. As a result, it becomes easy to remove the moisture and the impurity particles P together with the condensed droplets of the solvent vapor 4A.

  In the above description, the example of the case where the object to be dried W is transported while being held by the object to be dried holding jig 9 in the drying tank has been described. However, for example, when the object to be dried is large, the object to be dried is held. The object to be dried holding jig is not essential when it can be directly gripped and conveyed by an appropriate conveying mechanism without using a jig.

Further, in FIG. 12 (d) in the description of the third embodiment described above, the heat storage plate 38, but are drawn so as to move up above the vapor surface S _2, this is only an example, the second In order to finish the drying process, it is sufficient that the material W to be dried moves above the vapor-filled region V.
Therefore, the heat storage plate 38 may remain in the steam full region V at the end of the second drying process. In this case, since the heat storage plate 38 moves only in the steam-filled region V, the heat radiation amount is reduced as compared with the case where the heat-storing plate 38 is carried out of the steam-filled region V, and subsequently the other objects to be dried W are dried. In addition, the time for storing heat again can be shortened.

  In the first and third embodiments, the heat of each heating unit conducts heat through the mounting frame 7A, so that the dried object holding jig 9 and the dried object holding jig 9 are held. Although the example in the case where the dry matter W is heated was demonstrated, a heating part penetrates the clearance gap between each lattice frame 7e of the mounting frame 7A, and the vicinity of the dry matter W on the to-be-dried object holding jig 9 Comb-like heat dissipating fins extended to the end may be provided.

In addition, the components described in the above embodiments and modifications can be implemented by being appropriately combined or deleted within the scope of the technical idea of the present invention.
For example, the heating unit 48 of the fourth embodiment can be replaced with a heating unit provided in the vertical transport mechanism 47B in the same manner as in the first embodiment and the first modification.
Further, in the heating unit of the second embodiment, a heating temperature adjusting mechanism for adjusting the heating amount may be provided in the heating unit 28 as in the first modification of the first embodiment. In this case, when the object to be dried W is carried into the vapor-filled region V, since the temperature rise of the object to be dried W can be reduced by stopping or suppressing the heating of the heating unit 28, the first drying step 4A, the solvent vapor 4A can be efficiently condensed.

DESCRIPTION OF SYMBOLS 1, 11, 21, 31, 41 Steam drying apparatus 2, 42 Drying tank 2a Opening part 3 Steam source 4 Solvent 4A Solvent vapor 5 Solvent heating part 6, 46A, 46B Steam cooling pipe 7, 27, 47 Conveyance mechanism 7A Mounting Frame 7a Actuator 7e Lattice frame 8, 18, 28, 48 Heating part 8a Circulating path 9 Dried object holding jig 10 Cooling pipe 28a Radiator 28b Heating pipe 30 Heat storage member moving mechanism 38 Heat storage plate (heat storage member)
42A opening (loading opening)
42B opening (unloading opening)
47 transport mechanism 47A, 47B vertical transportation mechanism 47C belt conveying mechanism H heating medium _{M, M A, M B,} M C conveyance path P impurity particles _{S 1} solvent liquid surface _{S 2} vapor surface V steam filling region _{V 1} lower layer region _{V 2} middle region _{V 3} upper region W dried objects

Claims (7)

A vapor source for supplying solvent vapor adjusted to a constant temperature;
A drying tank that has an opening for carrying in and out an object to be dried, and fills the solvent vapor supplied from the vapor source below the opening to form a vapor-filled region;
A transport mechanism for transporting the object to be dried along a transport path extending inside and outside of the drying tank;
A heating unit that heats the object to be dried carried into the drying tank by the transport mechanism by a heating source that has a temperature equal to or higher than the predetermined temperature and is spaced apart from the vapor source;
A steam drying apparatus comprising: The steam drying apparatus according to claim 1,
The said drying part is provided in the said conveyance mechanism, The steam drying apparatus characterized by the above-mentioned. The steam drying apparatus according to claim 1 or 2,
The said heating part has a heating adjustment mechanism which adjusts the amount of heating, The steam drying apparatus characterized by the above-mentioned. The steam drying apparatus according to claim 1,
The said drying part is arrange | positioned around the conveyance path of the said conveyance mechanism in the said vapor | steam filling area | region, The steam drying apparatus characterized by the above-mentioned. The steam drying apparatus according to claim 4,
The opening comprises a carry-in opening for carrying the object to be dried into the drying tank and a carry-out opening for carrying the object to be dried out of the drying tank,
The steam filling area below the carry-in opening and the carry-out opening is partitioned, and is divided into a carry-in area and a carry-out area,
The said drying part is arrange | positioned around the conveyance path of the said conveyance mechanism in the said carrying-out area | region, The steam drying apparatus characterized by the above-mentioned. The steam drying apparatus according to claim 1,
The heating unit is
A heat storage member for storing heat of the solvent vapor in the vapor filling region;
A heat storage member moving mechanism that moves the heat storage member along at least a transport path of the transport mechanism in the steam-filled region;
A steam drying apparatus comprising: A vapor-filled region forming step of filling the drying tank with solvent vapor adjusted to a constant temperature to form a vapor-filled region;
A carrying-in process for carrying a material to be dried into the steam-filled area;
A first drying step of drying by bringing the material to be dried carried into the vapor-filled region into contact with the solvent vapor; and
A second drying step in which, after the start of the first drying step, the object to be dried is heated at a temperature equal to or higher than the predetermined temperature by a heating source disposed away from the vapor source; and
An unloading step of unloading the object to be dried from the vapor-filled region after the first and second drying steps;
A steam drying method comprising:

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