JP2003131394A - Resist collecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist collecting device which can securely separate and collect peeling liquid and photosensitive resist and reuse the peeling liquid without any problem firstly, reuse the peeling liquid with specified concentration as it is without any decrease in concentration nor performance deterioration secondly, maintain the consistency of a processing speed between a peeling device and other devices thirdly, perform supplementation with peeling liquid nearly as much as vaporized liquid fourthly, and eliminate the need for removing and cleaning operation by emulsification fifthly. SOLUTION: This resist collecting device 1 conveys a mixture F of the peeling device D supplied from the peeling device and the photosensitive resist E by a belt conveyor 6 which has fine air vents formed. The peeling liquid D is separated and sucked first by a slit suction hole 20 from the downside of the belt conveyor 6 and then the photosensitive resist E is sucked and collected by a slit suction hole 25 of a resist sucking unit 8 from the upperside of the belt conveyor 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist recovery device. That is, the present invention relates to a resist recovery device which is used as an auxiliary device in the manufacturing process of a printed wiring board and separates and recovers the stripping liquid and the photosensitive resist used in the stripping device.

[0002]

2. Description of the Related Art << Technical Background >> In the process of manufacturing a printed wiring board, a printed wiring board material, which is a copper-clad laminate, is transported by coating or sticking a photosensitive resist,
Exposure by applying negative film for circuit, → Phenomenon of melting and removing photosensitive resist other than circuit part, → Etching to melt and remove copper foil other than circuit part → Peeling and removing photosensitive resist of circuit part The printed wiring board having the circuit formed on the outer surface is manufactured by sequentially performing the steps of peeling, →, and so on. Then, in the above-mentioned peeling step, a peeling device is used, and the photosensitive resist of the circuit forming portion that has been cured and left is peeled and removed from the outer surface of the printed wiring board by spraying an alkaline peeling liquid. To be done. In this way, the stripping liquid used in the stripping device and the photosensitive resist stripped and removed are a mixed mixture. Therefore, such a mixture is supplied from the stripping device to a resist collecting device as an auxiliary device to separate the stripping liquid and the photosensitive resist,
The stripping solution is supplied to the stripping device and reused, and the photosensitive resist is discarded.

<< Regarding the Prior Art >> As the resist collecting apparatus of this type, conventionally, a drum type, a belt type, a filter type and the like have been typically used. The drum type resist recovery device uses a rotating hollow drum whose outer peripheral surface is made of a mesh net, supplies the mixture supplied from the stripping device to the inside, and passes the stripping liquid to the outer mesh net. The photosensitive resist collected and collected from the drum was discarded. The belt type resist recovery device is based on such a drum type and uses a mesh net belt conveyor. The mixture is supplied onto the belt conveyor to separate, flow down, recover and remove the stripping solution. The photosensitive resist left for use after being conveyed by the belt conveyor was collected, collected, and discarded. In addition, such a resist collecting device in which the drum type and the belt type are mixed is also used. The filter-type resist recovery device allows the mixture to pass through the filter, reuses the stripping solution separated and recovered through the filter, and collects, recovers and discards the photosensitive resist that has not passed through the filter. Was.

[0004]

<Regarding the First Problem> By the way, the following problems have been pointed out in such a conventional resist collecting apparatus. First, it has been pointed out that separation and recovery of the stripping solution and the photosensitive resist become uncertain, and the stripping solution may not be reused. In other words, printed wiring boards are becoming more precise, finer, and extremely thin, and the densification and miniaturization of circuits formed on the outer surface of them are remarkable. The thickness of the circuit is 35μ
m to 10 μm, and circuit width and spacing are 70 μm to 20 μm
It is miniaturized to about μm. Along with this, the photosensitive resist used for circuit formation is also becoming extremely thin in order to cope with such fine circuit formation, and the thickness / thickness thereof is from 25 μm to 25 μm in comparison with the conventional thickness of about 35 μm. 10μ
It has reached about m.

Therefore, recently, the photosensitive resist in the mixture recovered from the stripping device has been remarkably miniaturized, and the conventional drum type or belt type resist recovering device of this kind cannot easily separate it from the stripping solution. There wasn't. The mesh net of the drum and belt is too large, and the photosensitive resist that has been made finer is completely separated from the stripping solution and collected and collected.
There were difficulties. As a result, a large amount of photosensitive resist is likely to be mixed in the collected stripping solution, and if the stripping solution containing a large amount of photosensitive resist is supplied to the stripping device and reused, printing that would originally function is performed. Peeling and removal of photosensitive resist from the outer surface of wiring board material becomes difficult,
There is a defect that it will be disabled. Therefore, it has been pointed out that the peeling solution cannot be reused in many cases.

On the other hand, in the filter type resist collecting device, it is possible to collect and collect the finely divided photosensitive resist, that is, to separate it from the stripping solution. However, it has been pointed out that the filter is clogged with the miniaturized photosensitive resist. In other words, it has been pointed out that the conventional filter-type resist recovery device of this kind becomes clogged immediately after being used and cannot be used automatically, and cannot be continuously operated automatically.

<Regarding the Second Problem> Secondly, there was a problem that the separation and recovery of the stripping solution and the photosensitive resist became uncertain, and the concentration of the stripping solution decreased and the performance deteriorated. . That is, as described above, in the conventional drum type or belt type resist collecting device of this type, it is not easy to separate and collect the stripping solution from the photosensitive resist, and it is uncertain that the stripping solution collected is recovered. Even if not a large amount, a considerable amount of the photosensitive resist is mixed therein.
Then, by repeating the reuse, the mixing amount of the photosensitive resist gradually increases. Therefore, in the stripping solution collected and stored for reuse, the finely divided photosensitive resist is mixed, floated, and precipitated to be dissolved, altered, and emulsified, so that the concentration of the stripping solution is reduced accordingly. The so-called settling phenomenon of the peeling liquid that deteriorates the performance occurs,
Therefore, peeling and removal of the photosensitive resist in the peeling device also become a problem, which is a problem.

<Regarding Third Problem> Thirdly, when the concentration of the stripping solution is lowered and the performance is deteriorated, there is a problem in the processing speed of the stripping apparatus which reuses the stripping solution. Occurs. That is, the stripping liquid whose concentration is gradually lowered to a predetermined value or less due to repeated reuse is supplied from the resist collecting device side to the stripping device side, and the stripping liquid whose concentration is lowered and performance deteriorates is used to print. In order to remove and remove the photosensitive resist from the outer surface of the wiring board, it is necessary to slow down the speed of the conveyor that conveys the printed wiring board material inside the peeling device, or to enlarge the peeling device itself. Becomes And, the decrease in the conveyor speed of the peeling device does not match the conveyor speed of the developing device or etching device, which is the pre-process that is automatically lined up, and the matching problem occurs and the productivity decreases. Increasing the size of the device causes problems in cost and space.

<Regarding Fourth Problem> Fourthly, with respect to the stripping solution recovered and stored there for reuse, fresh stripping solution was sometimes replenished from the tank, but an appropriate amount. It has been pointed out that it is not easy to replenish the product, and the concentration and amount tend to be excessive. That is, in this type of conventional example, the number of printed wiring board materials supplied to the stripping device is counted as a measure against the above-described concentration drop of the stripping solution in the resist recovery device and performance deterioration.
For this reason, it has also been practiced to replenish fresh stripping solution to the stripping solution in storage for reuse, periodically and regularly for each predetermined number of sheets. However, the degree of density decrease and performance deterioration are various, and the circuits formed on the printed wiring board material are various, and the thickness and thickness of the photosensitive resist to be peeled and removed, the area and the amount thereof are different. Since it is diverse, it has been very complicated, troublesome and difficult to control so as to supply a suitable amount of the stripping solution. Therefore, the replenishment amount is inevitably excessive, and the concentration and amount of the stripping solution stored to be supplied to the stripping apparatus are excessive, and from this aspect, problems have been pointed out in terms of cost and performance of the stripping solution.

<Fifth Problem> Fifth, as described above, on the resist recovery device side, finely divided photosensitive resist is mixed in or floated in the stripping solution recovered and stored for reuse. It has been pointed out that if it is precipitated, it is likely to be dissolved and denatured and emulsified, which makes cleaning the storage tank difficult. That is, since the photosensitive resist is emulsified with the stripping solution and becomes a creamy or paste-like substance and adheres to the inner wall of the liquid tank, in the conventional resist collecting apparatus of this kind, the line is appropriately stopped to enter the liquid tank, It has been pointed out that the removal work is required, which is very troublesome and time-consuming, and the productivity is lowered because the line is stopped. Further, if the emulsification is left as it is, there is a risk that clogging will occur in various places from the resist recovery device to the stripping device, and this has also pointed out a problem.

<Regarding the Present Invention> The present invention has been made as a result of earnest research efforts by the inventor in order to solve the problems of the above-mentioned conventional examples in view of such circumstances. Then, the mixture of the stripping liquid and the photosensitive resist supplied from the stripping device, while being conveyed by the belt conveyor in which fine ventilation holes are formed, first, at the slit-shaped suction port of the liquid suction device from below the belt conveyor, The stripping solution is separated and sucked, and then from the belt conveyor at the slit suction port of the resist suction device.
It is characterized in that the photosensitive resist is sucked and collected.
The separated and sucked stripping solution flows down into the liquid tank, is collected and stored, and is then supplied to the stripping device for reuse. The sucked and collected photosensitive resist is put into the collecting tank and collected.
Further, when the concentration of the stripping solution falls below a predetermined value, fresh stripping solution is replenished to the liquid tank via the concentration sensor and the control valve.

Therefore, according to the present invention, firstly, the stripping solution and the photosensitive resist are reliably separated and recovered, and thus the stripping solution can be reused without any problems. Secondly, the concentration of the stripping solution is lowered,
It can be reused at a predetermined concentration without performance deterioration. Thirdly, between the peeling device and the developing device, etching device, etc.,
Consistency of processing speed is maintained, 4th, stripper solution replenishment is almost equivalent to evaporation, control is easy, and 5th, removal / cleaning work by emulsification is no longer necessary. The purpose is to propose a device.

[0013]

<< About Each Claim >> The technical means of the present invention for solving such a problem are as follows. First, claim 1 is as follows. The resist collecting apparatus according to claim 1 is used in a manufacturing process of a printed wiring board, and includes a supply unit, a belt conveyor, a liquid suction device,
It has a resist suction device and the like.
That is, a supply unit for supplying a mixture of a stripping solution after use and a photosensitive resist from a stripping device, a belt conveyor having air permeability for transporting after feeding, and arranged under the belt conveyor. A liquid suction device for sucking the liquid, and a resist suction device disposed on the belt conveyor and then sucking the photosensitive resist are provided.

Claim 2 is as follows. Claim 2
In the resist recovering device of claim 1, in claim 1, the stripping device sprays the alkaline stripping solution to strip and remove the photosensitive resist from the outer surface of the printed wiring board material. The supply unit is composed of a tubular body for flowing the mixture of the stripping solution after spraying and the photosensitive resist stripped and removed from the stripping device side to the resist collecting device side. The belt conveyor is endless and has fine air holes densely formed. The upstream side is located below the end of the supply unit, and the mixture is allowed to flow down on the upstream side. The liquid suction device exerts a suction force on the upstream side in the conveying direction to separate and suck the stripping liquid from the mixture via the belt conveyor. The resist suction device is characterized in that a suction force is exerted on the downstream side in the transport direction to suck and collect the photosensitive resist remaining on the belt conveyor. Claim 3 is as follows. According to a third aspect of the present invention, in the resist recovery apparatus according to the second aspect, a plurality of the liquid suction devices and the resist suction devices are provided side by side, and slit-shaped suction ports are formed along the lateral width direction of the belt conveyor. It is connected to a blower for generating a suction force.

Claim 4 is as follows. Claim 4
In the resist collecting apparatus, the liquid tank according to claim 3 is further provided below the liquid suction device, the belt conveyor, and the like with a vertical interval. In the liquid tank, the stripping liquid sucked through the slit-shaped suction port of the liquid suction device flows down through the blower, is collected and stored, and the stored stripping liquid is provided with a pump. Supplying to the peeling device for reuse via a pipe. Claim 5 is as follows. According to a fifth aspect of the present invention, in the resist collecting apparatus according to the fourth aspect, the collecting tanks are arranged below the end of the belt conveyor on the downstream side in the transport direction with a vertical interval. Then, in the recovery tank, the photosensitive resist sucked by the slit-shaped suction port of the resist suction device is
It is characterized by being input and recovered through a blower.
Claim 6 is as follows. According to a sixth aspect of the present invention, in the resist recovery apparatus according to the fifth aspect, the concentration sensor for the stripping solution arranged in the supply unit or the liquid tank is further connected to the liquid tank via a control valve and a pump. ,
A tank of fresh stripper. Then, based on the detection of the concentration sensor, when the concentration of the stripping solution falls below a predetermined value, the control valve switches to open, and thus the stripping solution fresh from the tank can be supplied to the liquid tank. It is characterized by.

<Regarding Operation> Since the present invention has such a configuration, it is as follows. This resist recovery device has a supply unit, a belt conveyor, a liquid suction device, a liquid tank, a resist suction device, a recovery tank, and the like, and is used in the manufacturing process of a printed wiring board and used in the peeling process. The liquid and the photosensitive resist are individually separated and collected in the next step. In the peeling process, the peeling liquid is sprayed by the peeling device,
The photosensitive resist is peeled and removed from the outer surface of the printed wiring board material. The stripping solution that has been sprayed by the stripping device and the photosensitive resist that has been stripped and removed form a mixed mixture. The supply unit is composed of a tubular body, and supplies this mixture by flowing it from the peeling device side to the resist collecting device side. The belt conveyor is endless and has fine ventilation holes densely formed, and the upstream side is located below the end of the supply section, and conveys the mixture that has been introduced, flowed down, and supplied from the upstream side to the downstream side.

A plurality of liquid suction devices are arranged below the upstream side of the belt conveyor, slit-shaped suction ports are formed in the lateral width direction, and are connected to a blower for generating suction force. By applying suction force while closely contacting the lower surface of the belt conveyor, only the peeling liquid is surely separated and sucked from the mixture through the fine ventilation holes of the belt conveyor. The sucked stripping solution flows down to the liquid tank via the blower and is collected and stored, but the photosensitive resist is not mixed, suspended, or settled, and is maintained at a predetermined concentration without concentration decrease or performance deterioration. In addition, neither dissolution alteration nor emulsification occurs. Then, the stripping solution thus stored is supplied to the stripping apparatus through the pipe or the pump and reused, but since the stripping apparatus is maintained at a predetermined concentration, the stripping apparatus may be kept at the predetermined processing speed. .

A plurality of resist suction devices are arranged on the downstream side of the belt conveyor, slit-shaped suction ports are formed in the lateral width direction, and the resist suction devices are connected to a blower for generating a suction force. A suction force is applied on the downstream side of the conveyor to suck and collect the remaining photosensitive resist. Therefore, the clogging of the fine ventilation holes of the belt conveyor can be avoided. The sucked photosensitive resist is put into a collecting tank through a blower and collected. Since the stripping solution that is circulated and reused is maintained at a predetermined concentration without a decrease in concentration and performance deterioration, it is sufficient to replenish the amount equivalent to evaporation. Therefore, when the concentration sensor detects that the concentration of the stripper is below the specified value, the control valve is switched to open, and fresh stripper is supplied from the tank to the liquid tank by the pump. Is the predetermined concentration,
It is maintained at a predetermined amount.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION
A detailed description will be given based on an embodiment of the invention shown in the drawings. 1, FIG. 2 and FIG. 3 are provided for explaining the embodiments of the invention regarding the resist collecting apparatus according to the present invention. FIG. 1 is a front explanatory view shown together with the peeling device. Figure 2
FIG. (1) of FIG. 3 is a plan explanatory view of a slit-shaped suction port of the liquid suction device, and (2) of FIG.
The figure is an explanatory plan view of a printed wiring board (material).

<< Regarding Printed Wiring Board A >> First, an outline of the presumed printed wiring board A will be described with reference to FIG. The printed wiring board A, which is also called an electronic circuit board, is a board for a wide variety of OA equipment,
It is used as a substrate for other electronic devices, and there are various types such as single-sided substrates, double-sided substrates, and multi-layered substrates (including those of recent build-up construction method). CSP and PBGA have also appeared. The printed wiring board A has become more and more precise, finer, ultrathin, flexible, multi-layered, etc. in recent years as the performance and functionality of electronic devices have become smaller and lighter. The density and miniaturization of the circuit B formed on one or both of the front surface and the back surface are remarkable. The printed wiring board A has dimensions of, for example, about 500 mm × 500 mm in length and width to about 330 mm × 250 mm,
The thickness of the insulating base material / insulating layer portion made of resin or glass cloth is about 1.0 mm to 60 μm, the portion of the circuit B (copper foil portion) is 75 μm to 35 μm, and recently 25 μm.
It is extremely thinned to about 10 μm or so, and even in the case of a multilayer substrate, the overall thickness is being extremely thinned to about 1.0 mm to 0.4 mm. The width and spacing of circuit B is also 0.1m
From m or less, there is a tendency for miniaturization to be about 70 μm to 20 μm.

<< Regarding Manufacturing Process of Printed Wiring Board A >> The printed wiring board A is manufactured by following the following steps as is well known. First, after the copper foil is attached to the outer surface of the insulating layer, which is an insulating base material made of resin or glass cloth, by hot pressing or the like, soft etching for roughening the copper foil surface is performed and cut into a work size. . Then, in many cases, the printed wiring board material C, which is a copper-clad laminate, prepared in this manner is subjected to a large number of holes for through-holes, and then subjected to panel plating to plate the inner walls of the through-holes. After that, a photosensitive resist, which is a protective film, is applied or attached in a film form on the outer surface of the printed wiring board material C. The thickness / thickness of this photosensitive resist has been changed from the conventional 35 μm to 2
It is becoming extremely thin, about 5 μm to 10 μm. The recent printed wiring board material C is a double-sided board having circuits B formed on both outer surfaces (both front and back surfaces), and a double-sided copper-clad laminate is often used, but the circuit is formed only on one outer surface. A single-sided board having B formed thereon may be used, and a single-sided copper-clad laminate may be used. The through hole is also called a via hole, and one printed wiring board material C (printed wiring board A) is formed with a large number of extremely small diameters of hundreds or thousands, and the diameter thereof is 0.5 mm ~
Many of them are about 0.2 mm or less. The through holes are used for connecting between the circuits B on both outer surfaces and for mounting / attaching the base of a (thin type) component mounted on the circuits B.

Then, a circuit photograph, which is a negative film of the circuit B, is applied to such a printed wiring board material C,
Expose. As a result, the photosensitive resist coating the outer surface of the printed wiring board material C leaves the portion where the circuit B is exposed and cured, and the other unnecessary portions are dissolved and removed by spraying a developing solution which is a chemical solution. Thereafter, in the copper foil on the outer surface of the printed wiring board material C, the photosensitive resist is hardened to leave the circuit B formation portion covered and protected, and the photosensitive resist is removed by dissolution as described above. However, it is dissolved and removed / etched by spraying an etching solution (corrosion solution) which is a chemical solution. Then, the remaining photosensitive resist of the cured circuit B forming portion is peeled and dissolved by spraying a peeling liquid which is a chemical liquid, so that the remaining copper foil of the circuit B forming portion of the printed wiring board material C is removed. A predetermined circuit B is formed on the outer surface, so that the printed wiring board A is manufactured. Incidentally, on the outer surface of the printed wiring board A manufactured by following these steps, the protective film of the formed circuit B is formed by a photosensitive resist as a post-treatment step according to the above-mentioned step. It The manufacturing process of the printed wiring board A is as described above.

<< Outline of the resist collecting apparatus 1 >> Hereinafter, the resist collecting apparatus 1 of the present invention will be described with reference to FIGS.
Will be described in detail with reference to. As described above, the peeling device 2 is used in the peeling step during the manufacturing process of the printed wiring board A.
Is used to spray the stripping solution D onto the printed wiring board material C to strip and remove the photosensitive resist E from the outer surface thereof (see the right part of FIG. 1). That is, in the peeling device 2, the alkaline peeling liquid D is jetted from the spray nozzles 4 arranged opposite to the printed wiring board material C which is horizontally conveyed by a conveyor such as the roller conveyor 3, so that the printed wiring is The photosensitive resist is swelled, peeled off, and removed from the outer surface of the substrate material C (including the inner wall of the through hole opened between both outer surfaces and the inner wall of the blind via hole opened only on one outer surface).

The resist collecting device 1 is provided as an auxiliary device of the peeling device 2 in the manufacturing process of the printed wiring board A. Then, the stripping solution D and the photosensitive resist E used in the stripping device 2 are individually separated and collected. The resist collecting apparatus 1 includes the following supply unit 5, belt conveyor 6, liquid suction device 7, resist suction device 8, liquid tank 9, and collecting tank 10. The outline of the resist recovery device 1 is as described above. The details will be described below.

<Regarding Supply Unit 5> First, the supply unit 5 of the resist recovery apparatus 1 was stripped and removed from the mixture F of the stripping solution D after use and the photosensitive resist E, that is, the stripping solution D after spraying. The mixture F with the photosensitive resist E is flowed from the peeling device 2 side to the resist collecting device 1 side. That is, the supply unit 5 in the illustrated example is composed of a pipe body / sink pipe that is horizontally installed with a slight inclination, and one end portion 11 ₁ opens onto the partition floor plate 12 of the peeling device 2 and the other end portion 11 ₂ , Vertical input pipe 1
It is opened on the belt conveyor 6 of the resist collecting device 1 via As described above, the supply unit 5 is made of a tube that connects the stripping device 2 side and the resist collecting device 1 side, and the mixture F is fed from the stripping device 2 side to the resist collecting device 1 side.
Pour into the side and supply. The supply unit 5 has such a configuration.

Next, the belt conveyor 6 of the resist collecting apparatus 1 is air permeable, and conveys the supplied mixture F horizontally at the upper part. This belt conveyor 6
Fine ventilation holes are densely formed, and the upper upstream side G
But located in the other end portion 11 ₂ below the supply unit 5, mixture F is made to flow down thereon. Also, this belt conveyor 6
Is endless and is stretched with tension between the drive roller 14 (connected to the motor), the guide roller 15, and the tension roller 16 whose axes are oriented in the horizontal direction.

The belt conveyor 6 will be described in more detail. The belt conveyor 6 carries the mixture F on the upper side of the traveling as described above, and moves from the upstream side G to the downstream side H.
And is conveyed along the conveyance direction J. In other words, the lower feeding pipe 13 of the other end portion 11 ₂ of the supply unit 5, located upstream side G of the belt conveyor 6, the mixture F is made to flow down on, have been, downstream H in I placing the mixture F Travel to and transport to. The belt conveyor 6 is densely formed with many fine ventilation holes. The diameter of the vent hole is set to a dimension that does not allow even the miniaturized photosensitive resist E to pass, and is set to, for example, several tens of μm to several μm. 17
Is a table, which is disposed below the upper belt conveyor 6 which travels in this way, and prevents the belt conveyor 6 from bending downward due to the weight of the loaded mixture F.
In addition, openings 18 are formed in the table 17 so as not to interfere with the suction force of the liquid suction device 7 and the resist suction device 8 described below. Reference numeral 19 is a guide table of the belt conveyor 6 which runs at the bottom.
The belt conveyor 6 has such a structure.

<< Regarding Liquid Suction Device 7 >> Next, the liquid suction device 7 of the resist collecting apparatus 1 is disposed below the belt conveyor 6 and sucks the stripping liquid D first. That is, the liquid suction device 7 applies a suction force on the upstream side G in the transport direction J to separate the stripping liquid D from the mixture F via the belt conveyor 6.
Suction. A plurality of slit-like suction ports 20 are formed in the lateral direction K (see FIG. 1) of the belt conveyor 6 (see also FIG. 3 (1)) and a suction force is generated. It is connected to Blower-21.

The liquid suction device 7 will be described in more detail. On the lower surface of the upstream belt conveyor 6 on the upstream side, in the illustrated example, three liquid suction devices 7 are arranged in a line in the transport direction J while facing each other from the right angle direction. This liquid suction device 7
It is in the form of a rectangular tube or other tube, and is arranged to cover the entire width of the belt conveyor 6 along a lateral width direction K that is orthogonal to the transport direction J in the horizontal plane. Then, a suction force is applied to the mixture F from the slit-shaped suction port 20 formed additionally through the belt conveyor 6 in which a large number of fine ventilation holes are formed, so that only the stripping liquid D is selectively selected from the mixture F. Separate and aspirate. The slit-shaped suction port 20 is slidably contacted and abuts below the traveling belt conveyor 6 through the opening 18 formed in the table 17 without any vertical gap. In the illustrated example, one slit-shaped suction port 20 is formed in one liquid suction device 7, but it is also possible to form two or more slit-shaped suction ports 20.

The slit-shaped suction port 20 shown in the drawing is formed at the tip and the upper end of a projection 22 vertically projecting from the liquid suction device 7, and the projection 22 has a flat shape and is flat inside. It has a communication hole. And each liquid suction device 7
The blower -21 is connected to the blower -21 via the pipe 23. The blower -21 generates a suction force by driving the attached motor 24, and sucks the liquid suction device 7 and the slit-shaped suction port 20 via the pipe 23. Supply power. The other end of the pipe 23
The lower end is opened on the liquid tank 9 through the blower 21. A vacuum pump, another pump, an ejector, or the like can be used instead of the blower-21.
The liquid suction device 7 has such a configuration.

<< Regarding the Resist Suction Device 8 >> Next, the resist suction device 8 of the resist recovery device 1 is disposed on the belt conveyor 6 and then sucks the photosensitive resist E. That is, the resist suction device 8 exerts a suction force on the downstream side H in the transport direction J to suck and collect the photosensitive resist E remaining on the belt conveyor 6. A plurality of slit-shaped suction ports 25 are formed in the lateral width direction K of the belt conveyor 6 and are connected to a blower 26 for generating suction force.

The resist suction device 8 will be described in more detail. On the downstream side H of the upper belt conveyor 6, in the illustrated example, three resist suction devices 8 are arranged in a line in the transport direction J while facing each other from the right angle direction. The resist suction device 8 is in the shape of a rectangular tube or the like, and is arranged so as to cover the entire width of the belt conveyor 6 along the lateral width direction K orthogonal to the transport direction J on the horizontal plane. Then, from the slit-shaped suction port 25 formed additionally, the photosensitive resist E conveyed on the belt conveyor 6, that is, the residual photosensitive resist E from which the stripping solution D has been separated, sucked, and removed from the mixture F is sucked. A force is applied to suck and collect the photosensitive resist E. The slit-shaped suction port 25 is the opening 18 formed in the table 17 described above.
And face each other from above via the belt conveyor 6. In the illustrated example, one slit suction port 25 is formed in one resist suction device 8, but it is also possible to form two or more slit suction ports 25.

The slit-shaped suction port 25 shown in the figure is a tip end of a protruding portion 27 vertically protruding from the resist suction device 8.
The protruding portion 27 is formed at the lower end and has a flat shape and has a flat communication hole inside. Each resist suction device 8 is connected to a blower 26 via a pipe 28. The blower 26 generates a suction force by driving an attached motor 29, and the resist suction device 8 passes through the pipe 28. A suction force is supplied to the slit-shaped suction port 25. The other end / lower end of the pipe 28 is opened above the recovery tank 10 via the blower 26. A vacuum pump, another pump, an ejector or the like may be used instead of the blower 26. The resist suction device 8 has such a structure.

<< Regarding Liquid Tank 9 >> Next, the liquid tank 9 of the resist collecting apparatus 1 is disposed below the liquid suction device 7, the belt conveyor 6 and the like at a vertical interval. This liquid tank 9
The peeling liquid D sucked through the slit-shaped suction port 20 of the liquid suction device 7 flows down, is collected and stored through the blower 21 and the pipe 23, and the stored peeling liquid D is pumped by the pump 30. It is supplied to the peeling device 2 for reuse via the attached pipe 31. That is, the liquid tank 9 in the illustrated example is formed in the lower part of the resist recovery device 1, and the stripping solution D sucked by the liquid suction device 7 in the upper part flows down, recovers, and flows through the pipe 31 and the like. Be stored. Of course, other belt conveyors 6
The peeling liquid D that has passed through the above, adhered, and flowed down is also flowed down, collected, and stored in the liquid tank 9 below. 32 is a heating heater provided in the liquid tank 9, and this heating heater 32 is
The stripping solution D stored in the solution tank 9 is heated to, for example, about 55 ° C. to be prepared for reuse. Then, one end of the pipe 31 is connected to the liquid tank 9 via the adjustment valve 33, and the pipe 31 is connected to each spray nozzle 4 of the peeling device 2 after passing through the pump 30. There is. Liquid tank 9
Is like this.

<< Recovery Tank 10 >> Next, the recovery tank 10 of the resist collecting apparatus 1 is disposed below the end of the belt conveyor 6 on the downstream side H in the transport direction J with a vertical interval. Then, the photosensitive resist E sucked through the slit-shaped suction port 25 of the resist suction device 8 is introduced and collected through the blower 26. That is, the recovery tank 10 in the illustrated example is formed at the lower end of the resist recovery apparatus 1 by being partitioned from the liquid tank 9 by the vertical partition wall 34. Then, the photosensitive resist E sucked by the resist suction device 8 is transferred to the pipe 2
After being input and collected via 8 etc., it is disposed of. Of course, the photosensitive resist E dropped from the downstream end H of the belt conveyor 6 on the upper side (that is, the photosensitive resist E sucked and collected by the resist suction device 8) is also collected on the lower collecting tank 10. Input, collection and disposal. Collection tank 1
0 is like this.

<< Regarding the Concentration Sensor 35, Control Valve 36, etc. >> Further, the resist collecting apparatus 1 is arranged in the supply unit 5 or the liquid tank 9 as shown in FIG.
It comprises a concentration sensor 35 for the stripping solution D, and a tank 38 for the fresh stripping solution D, which is connected to the liquid tank 9 via a control valve 36 and a pump 37. That is, the concentration sensor 35 detects the concentration of the stripping liquid D in the mixture F of the stripping liquid D and the photosensitive resist E supplied by the supply unit 5, or the concentration of the stripping liquid D stored in the liquid tank 9. It consists of pH meter. Then, it is arranged in one or both of the supply unit 5 and the liquid tank 9. Then, the concentration of the alkaline stripping solution D detected by the concentration sensor 35, that is, the pH value of the stripping solution D is sent to the control unit 39. Control unit 39
When it is determined that the concentration of the peeling liquid D is below a predetermined value based on the detection of the concentration sensor 35, that is, when the paper value / alkalinity of the peeling liquid D is below a predetermined value, an open signal is output to the control valve. The drive signal is sent to the pump 37 and the drive signal is sent to the pump 37. Therefore, the normally closed control valve 36 is switched to open so that the fresh stripping solution D is supplied from the tank 38 to the liquid tank 9 through the pipe 40. The tank 38 can store and supply the fresh stripping solution D obtained by diluting the stock solution. In the figure, 41 is a peeling chamber of the peeling device 2, 42
Is a recovery chamber of the resist recovery apparatus 1, and 43 is an upper lid thereof. The density sensor 35, the control valve 36, etc. are configured in this way.

<< Regarding Operation and the Like >> The resist collecting apparatus 1 of the present invention is constructed as described above. Therefore, it becomes as follows. This resist collecting apparatus 1 is used in a manufacturing process of a printed wiring board A, and a mixture F of a used stripping solution D and a photosensitive resist E is used to trace the stripping solution D and the photosensitive resist E through the following steps. Separately and collect. In the peeling process of the manufacturing process of the printed wiring board A, the peeling device 2 sprays the alkaline peeling liquid D,
From the outer surface of the printed wiring board material C to the photosensitive resist E
Is removed and removed (see the right part of FIG. 1).

In the peeling device 2, the peeling liquid D after use
The photosensitive resist E, that is, the stripping solution D after being sprayed and the photosensitive resist E stripped and removed is a mixed mixture F. The photosensitive resist E is mixed, floated or precipitated in the stripping solution D. The supply part 5 of the resist recovery device 1 is made of a tubular body, and the mixture F of the stripping solution D and the photosensitive resist E is supplied by flowing from the stripping device 2 side to the resist recovery device 1 side (see FIG. See 1). The belt conveyor 6 of the resist recovery device 1 conveys the supplied mixture F. Ie belt conveyor 6
Is fine vent without endless are densely formed, upstream G is positioned below the other end portion 11 ₂ of the supply unit 5, the input on the belt conveyor 6, a falling by mixture F, Transporting direction J Transporting from upstream side G to downstream side H (see FIG. 2).

The liquid suction device 7 of the resist collecting apparatus 1 is arranged below the upstream side G of the belt conveyor 6, and first sucks the stripping liquid D from the mixture F conveyed by the belt conveyor 6. (See Figure 2). That is, the liquid suction device 7
Are provided under the belt conveyor 6, a slit-shaped suction port 20 is formed in the lateral width direction J of the belt conveyor 6 (see also FIG. 3A), and a blower for generating suction force. 21 is connected. Therefore, the slit-shaped suction port 20 is brought into close contact with the lower surface of the upstream side G of the belt conveyor 6, while applying a suction force, from the mixture F on the belt conveyor 6 through the fine ventilation holes of the belt conveyor 6, The stripping solution D is separated and sucked. The stripping liquid D sucked through the slit-shaped suction port 20 of the liquid suction device 7 flows down, collects, and is stored in the liquid tank 9 that is vertically arranged with a space between the blower 21. (See Figure 2). In addition, the liquid tank 9 of the resist collecting apparatus 1 is as described above.
The stripping solution D stored in (1) is supplied to the stripping device 2 via the pipe 31 and the pump 30 and is reused (see FIG. 1).

On the other hand, the resist suction device 8 of the resist recovery device 1 is arranged on the downstream side H of the belt conveyor 6 and sucks the photosensitive resist E next from the belt conveyor 6 (FIG. 2). See). That is, a plurality of resist suction units 8 are provided on the belt conveyor 6, slit-shaped suction ports 25 are formed in the lateral width direction J of the belt conveyor 6, and a blower 26 for generating suction force is formed.
It is connected to the. Thus, the slit-shaped suction port 25 exerts a suction force on the downstream side H of the belt conveyor 6 to suck and collect the photosensitive resist E remaining on the belt conveyor 6. The photosensitive resist E sucked through the slit-shaped suction port 25 of the resist suction device 8 is put into and collected by the blower 26 into the collecting tank 10 arranged at the lower side with a vertical interval (see FIG. 2). The photosensitive resist E collected in the collecting tank 10 of the resist collecting apparatus 1 in this manner is subsequently discarded.

By the way, in the resist collecting apparatus 1, the concentration sensor 35 for the stripping solution D is arranged in the supply section 5 or the liquid tank 9 (see FIG. 1). Therefore, based on the detection of the concentration sensor 35, when the concentration of the peeling liquid D is below a predetermined value, the control valve 36 is switched to open. Then, fresh stripping solution D is replenished from the tank 38 to the liquid tank 9 through the open control valve 36 and the pump 37.

<< Regarding Each Operation >> The resist collecting apparatus 1 becomes the following first, second, third, fourth and fifth by following the above steps. First
In the resist collecting apparatus 1, as shown in the above step, the stripping solution D is sucked from the mixture F through the slits of the liquid suction device 7 through a large number of fine ventilation holes of the belt conveyor 6. By the method of sucking into the mouth 20, even if the photosensitive resist E is made finer, the peeling liquid D alone is reliably separated, sucked and collected while being surely left on the belt conveyor 6. That is, a. A belt conveyor 6 is used in which a ventilation hole having a fine diameter is formed so that the miniaturized photosensitive resist E does not pass through, and the ventilation hole has a diameter much smaller than that of the mesh net of the conventional example of this kind. b. Further, the peeling liquid D is sucked through the fine vent holes by exerting a downward suction force instead of merely passing or flowing by gravity. c. Moreover, this suction force acts by the slit-shaped suction port 20 and also acts a plurality of times. By these a, b, and c, the photosensitive resist E is left on the belt conveyor 6 and the stripping solution D
All of the peeling liquid D is sucked and collected without remaining due to the strong suction force while being reliably separated.

Secondly, in the stripping solution D stored in the solution tank 9 as shown in the above step, even if the photosensitive resist E which has been made fine is mixed, floated or precipitated. Not in. Therefore, the stored stripping solution D is maintained at a predetermined concentration without any change in solubility or emulsification due to the mixing of the photosensitive resist E, that is, no decrease in concentration or performance deterioration.

Thirdly, since the stripping solution D circulated and reused via the liquid tank 9 is maintained at a predetermined concentration in this way, the stripping apparatus 2 in the step also keeps the predetermined processing speed. Maintained. That is, since the peeling liquid D is reliably held at the desired predetermined concentration, even in the peeling device 2, the roller conveyor 3 remains set at the desired predetermined transport speed, that is, the developing device in the previous process or The peeling process of the photosensitive resist E from the printed wiring board material C can be continued while the conveyance speed control matched with the etching apparatus is being controlled. It is not necessary to control the decrease of the transport speed due to the decrease of the concentration of the stripping solution D.

Fourthly, since the alkaline stripping solution D which is circulated and reused is maintained at a predetermined concentration without a decrease in concentration and performance deterioration as described above, the replenishment of the stripping solution D is almost the same in the above steps. It is sufficient to replenish the amount corresponding to evaporation. That is, based on the detection of the concentration sensor 35, the control valve 36 and the pump 37 are controlled to appropriately supply the fresh stripping solution D corresponding to evaporation from the tank 38, so that the stripping solution D can easily have a predetermined concentration. ， Maintained to a specified amount.

Fifth, since the photosensitive resist E is not mixed in the stripping liquid D stored in the liquid tank 9 in the above step, neither dissolution alteration nor emulsification occurs. Therefore, it is not necessary to remove and clean the liquid tank 9 that has been emulsified to form a cream or paste.

<< Others >> First, according to the resist collecting apparatus 1, as described above, the suction is performed through the fine ventilation holes formed in the belt conveyor 6, so that the belt conveyor 6 can be sucked. Stripping solution D from mixture F
Only this is reliably separated and recovered, but this point is further ensured by the following. That is, only the photosensitive resist E remains on the belt conveyor 6 from which the stripping solution D has been separated, sucked, and removed, but the photosensitive resist E remaining in this way is surely removed by the resist suction device 8. Everything is sucked, collected and removed. Therefore, although the vent hole formed in the belt conveyor 6 is particularly fine, the opening is closed by the photosensitive resist E and the clogging does not occur. And with such fine air vents that are not clogged,
After that, the separation liquid D is separated and collected again using the liquid suction device 7. Therefore, from this aspect as well, the function of the vent holes of the belt conveyor 6 is always normally ensured, the belt conveyor 6 is automatically operated continuously without any problem, and the separation liquid D is separated and collected by the liquid suction device 7. It is guaranteed and can be implemented.

Secondly, dissolution alteration and emulsification due to the mixing of the photosensitive resist E into the stripping solution D occur over a certain period of time. That is, as in the above step, at the stage immediately after the two are mixed as the mixture F in the peeling device 2, the problem of dissolution alteration and emulsification does not occur yet. The photosensitive resist E is
It merely floats or precipitates in the stripping solution D. On the other hand, in the storage step in the liquid tank 9 in the above step, if the photosensitive resist E is mixed in the stripping solution D, dissolution deterioration and emulsification occur over time.

Thirdly, the resist collecting apparatus 1 is
It can be applied and used in the peeling process / peeling device 2 in the plating process during the manufacturing process of the printed wiring board A. That is,
In the illustrated example described above, the photosensitive resist E on the circuit B forming portion is peeled and removed by spraying the peeling liquid D, but conversely, after the portion other than the circuit B portion is covered with the photosensitive resist E. After plating the circuit B portion, the photosensitive resist E is peeled off by spraying the peeling liquid D,
It can also be applied and used for the stripping device 2 in the plating step for removing.

[0050]

<Characteristics of the Invention> As described above, in the resist recovery apparatus according to the present invention, a fine vent hole is formed in the mixture of the stripping solution and the photosensitive resist supplied from the stripping apparatus. While transporting on the belt conveyor, first, the peeling liquid is separated and sucked from below the belt conveyor with the slit suction port of the liquid suction device, and then from above the belt conveyor with the slit suction port of the resist suction device. It is characterized in that the photosensitive resist is sucked and collected. The separated and sucked stripping solution flows down into the liquid tank, is collected and stored, and is then supplied to the stripping device for reuse. The sucked and collected photosensitive resist is put into the collecting tank and collected. Further, when the concentration of the stripping solution falls below a predetermined value, fresh stripping solution is replenished to the liquid tank via the concentration sensor and the control valve. Therefore, the present invention exhibits the following effects.

<Regarding the First Effect> Firstly, the stripping solution and the photosensitive resist are reliably separated and collected, so that the stripping solution can be reused without any problem. That is, in this resist collecting device, first, while being conveyed by a belt conveyor having fine ventilation holes, the stripping liquid is first sucked by a liquid suction device from below, and then the resist suction device is exposed from above. Aspirable resist is collected. Therefore, even if the photosensitive resist is miniaturized, it is possible to reliably separate only the stripping liquid,
Can be collected. The clogging of the ventilation holes of the belt conveyor is also prevented. Therefore, it is possible to reliably prevent the situation where a large amount of the photosensitive resist is mixed in the stripping solution collected in the liquid tank as in the above-described conventional example. Therefore, collection,
The stored stripping solution can be supplied to the stripping apparatus and reused / recycled and recycled without any problem. For example, in a general production line, the stripping solution can be saved by several tons per day.

<Second Effect> Secondly, the peeling liquid can be reused at a predetermined concentration without lowering the concentration or deteriorating the performance. That is, in this resist collecting apparatus, as described above, even if the photosensitive resist is miniaturized,
Only the stripper is reliably separated and collected. Therefore, as in the conventional example of this kind described above, even if a small amount of the finely divided photosensitive resist is mixed, floated, or precipitated in the stripping solution collected in the liquid tank, it is not possible to dissolve, modify, or emulsify. Be avoided. Therefore, the stripping liquid is supplied to the stripping device at a predetermined concentration without deterioration in performance due to dissolution alteration or emulsion and deterioration in performance, and so-called fatigue phenomenon does not occur. Can be reused.

<Third Effect> Thirdly, it is possible to easily maintain the matching of the processing speed between the peeling device and the phenomenon device or the etching device. Both the predetermined concentration of the stripping solution and the predetermined processing speed of the stripping device are always kept constant. That is, in this resist collecting apparatus, the stripping solution is supplied to the stripping apparatus at a predetermined concentration for reuse without a decrease in concentration and performance deterioration as described above. Therefore, as in the above-described conventional example of this kind, since the stripping solution whose concentration is lowered and performance is deteriorated is used, in the stripping device, the speed of the conveyor for conveying the printed wiring board material is reduced,
It is not necessary to enlarge the peeling device. The conveyor speed of the peeling device may be the same as the conveyor speed of the developing device and the etching device of the previous process that are automatically lined, and it may be the same as the initial setting, and the consistency is maintained.
It has excellent productivity. Further, it is not necessary to enlarge the peeling device, and it is excellent in terms of cost and space.

<Regarding Fourth Effect> Fourthly, the replenishment of the stripping solution is almost equivalent to vapor, and the control is easy. That is, in this resist collecting apparatus, the stripping solution is supplied to the stripping apparatus at a predetermined concentration for reuse without a decrease in concentration and performance deterioration as described above. Therefore, as in the conventional example of this kind described above, the number of printed wiring board materials supplied to the peeling apparatus is counted, and the number of printed wiring board materials is periodically set every predetermined number.
It is not necessary to supply fresh stripping solution on the side of the resist recovery device on a regular basis under complicated control. That is, the alkaline stripping solution having a predetermined amount and a predetermined concentration is first set and used, and after that, it is sufficient to replenish the amount corresponding to the evaporation, and the control is easy. Moreover, by providing a concentration sensor, a control valve, etc., such control is automated. Further, unlike the conventional example of this kind described above, there is no need to replenish an excessive concentration or amount of the stripping solution, and this aspect is also excellent in cost and performance.

<Regarding the Fifth Effect> Fifth, it is not necessary to carry out the removal / cleaning work by emulsification. That is, in this resist collecting apparatus, as described above,
Even if the photosensitive resist is miniaturized, the stripping solution is reliably separated and collected. Therefore, unlike the conventional example of this kind, it is avoided that the finely divided photosensitive resist is mixed, floated, or precipitated in the stripping solution collected in the liquid tank to be dissolved, altered, or emulsified. . Therefore, it does not become an emulsified cream or paste and does not adhere to the inner wall of the liquid tank. As in the conventional example of this kind, the line is frequently stopped to enter the liquid tank for removal / cleaning work. Efficient, with no need to do it. Also, because the line is not stopped,
It has excellent productivity. Furthermore, since the emulsification is avoided, the risk of clogging at various places from the resist recovery device to the stripping device is eliminated. In this way, all the problems existing in this type of conventional example are solved,
The effects of the present invention are remarkably large.

[Brief description of drawings]

FIG. 1 is a front explanatory view showing a resist recovery device according to the present invention together with a stripping device, which is used for explaining an embodiment of the invention.

FIG. 2 is a side view for explaining the embodiment of the present invention.

FIG. 3 is used to explain the embodiment of the present invention, and (1) is an explanatory plan view of a slit-shaped suction port of a liquid suction device,
(2) FIG. 2 is a plan view of a printed wiring board (material).

[Explanation of symbols]

1 Resist Collection Device 2 Stripping Device 3 Roller Conveyor 4 Spray Nozzle 5 Supply Unit 6 Belt Conveyor 7 Liquid Suction Device 8 Resist Suction Device 9 Liquid Tank 10 Recovery Tank 11 ₁ One End 11 _{2 The} Other End 12 Partition Floor Plate 13 Input Pipe 14 Drive Roller 15 Guide roller 16 Tension roller 17 Table 18 Opening 19 Guide table 20 Slit suction port 21 Blower 22 Projection 23 Piping 24 Piping 24 Motor 25 Slit suction port 26 Blower 27 Projection 28 Piping 29 Motor 30 Pump 31 Piping 32 Addition Heater 33 Adjustment valve 34 Partition wall 35 Concentration sensor 36 Control valve 37 Pump 38 Tank 39 Control unit 40 Piping 41 Stripping chamber 42 Collection chamber 43 Top lid A Printed wiring board B Circuit C Printed wiring board material D Stripping solution E Photosensitive resist F Mixture G Flow side H downstream J conveying direction K the width direction

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masahiro Midorikawa             4-1-1 Higashi-Komatsugawa, Edogawa-ku, Tokyo             Within Tokyo Kakoki Co., Ltd. (72) Inventor Ryoji Abe             4-1-1 Higashi-Komatsugawa, Edogawa-ku, Tokyo             Within Tokyo Kakoki Co., Ltd. (72) Inventor Hiroaki Ito             4-1-1 Higashi-Komatsugawa, Edogawa-ku, Tokyo             Within Tokyo Kakoki Co., Ltd. F term (reference) 2H096 AA26 BA05 EA02 HA30 LA03                       LA30                 4D026 BA01 BB03 BC11 BD02 BE05                 5E339 BE13 CG01

Claims (6)

[Claims] 1. A resist recovery apparatus used in a process for manufacturing a printed wiring board, comprising: a supply section for supplying a mixture of a stripping solution after use and a photosensitive resist from the stripping apparatus; And a liquid suction device that is arranged below the belt conveyor to suck the stripping liquid, and a resist suction device that is disposed on the belt conveyor and then sucks the photosensitive resist. A resist recovery apparatus comprising: 2. The resist recovery device according to claim 1, wherein the stripping device sprays the alkaline stripping solution to strip and remove the photosensitive resist from the outer surface of the printed wiring board material. The supply unit is a tube body that flows the mixture of the stripping solution after spraying and the photosensitive resist stripped and removed from the stripping device side to the resist collecting device side, and the belt conveyor is endless. A fine air hole is formed densely, the upstream side is located below the end of the supply unit, and the mixture is allowed to flow down on the upstream side, and the liquid suction device sucks the upstream side in the transport direction. Applying force,
The stripping solution is separated and sucked from the mixture via the belt conveyor, and the resist suction device exerts suction force on the downstream side in the transport direction to suck the photosensitive resist remaining on the belt conveyor, A resist recovery device characterized by collecting. 3. The resist recovery device according to claim 2, wherein a plurality of the liquid suction devices and the resist suction devices are provided side by side, and slit suction ports are formed along the lateral width direction of the belt conveyor. At the same time, the resist recovery device is connected to a blower for generating a suction force. 4. The resist recovery apparatus according to claim 3, further comprising a liquid tank disposed below the liquid suction device, the belt conveyor, etc. at a vertical interval. The stripping liquid sucked by the slit-shaped suction port of the liquid suction device flows down, is collected and stored through the blower, and the stored stripping liquid is supplied through a pipe with a pump. A resist recovery device characterized by being supplied to a stripping device for reuse. 5. The resist recovery apparatus according to claim 4, further comprising a recovery tank disposed below the end of the belt conveyor on the downstream side in the transport direction with a vertical interval. A resist collecting apparatus, wherein the tank is charged with and collects the photosensitive resist sucked through a slit-shaped suction port of the resist suction device through the blower. 6. The resist recovery apparatus according to claim 5, further comprising a concentration sensor for the stripping solution, which is arranged in the supply unit or the liquid tank, and is connected to the liquid tank via a control valve and a pump. And a fresh tank of the stripping solution, and based on the detection of the concentration sensor, when the concentration of the stripping solution falls below a predetermined value, the control valve is switched to open, A resist recovery apparatus, wherein the stripping solution fresh from the tank can be supplied to the liquid tank.