JPH0959797A - Automatic liquid treating line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and automatically surface-treat a plateshaped material by detecting the size of the material continuously conveyed in a horizontal position, setting the material in a vertical position and introducing the material into a liq. treating tank corresponding to the size. SOLUTION: A plate-shaped material 1 such as a printed circuit board is cleaned, bored and so on as pretreatment, the size is detected, the four corners are held by jigs 5 and 6, and then the material is set in a vertical position, introduced into a plating tank corresponding to the size and vertically traveled on a rail 15. Air is blown from a bottom pipe 11 to agitate a plating soln. 8, and a pulse current is applied with the material 1 as a cathode to electroplate the surface. A metallic-mesh cylinder packed with many metallic balls of copper, etc., is used as an anode 9 and made vertically slidable in accordance with the size of the material 1 and the amt. of the soln. 8. Consequently, a current is applied on the entire surface of the material 1 at a uniform density, and a plating film uniform in thickness is formed on the entire surface of the material 1.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an automatic liquid processing line suitable for liquid processing of various structural materials and functional materials. In particular, plate-shaped materials such as copper-clad laminates and / or
Alternatively, it is preferably applied to etching.

[0002]

2. Description of the Related Art Conventionally, for example, plating, etching, electrodeposition coating, liquid jetting, underwater electric discharge treatment, and other surface treatments have been performed as treatments in liquids or jetting liquids. It was necessary to efficiently process the object to be processed and to improve the quality of the process. In particular, when the object to be processed is a plate-like object such as a printed circuit board, a large space is required in each process, and the most important liquid processing process is the rate-determining step, which is a bottleneck for speeding up the entire process. Was becoming.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic liquid treatment apparatus capable of efficiently and highly accurately automating liquid treatment of various structural materials and functional materials. In particular, the present invention provides a processing line suitable for plating and / or etching a plate-shaped material such as a printed circuit board.

[0004]

Means for Solving the Problems As a result of intensive studies made by the present inventors, the above-mentioned problems are solved by vertically racking an object to be processed conveyed in a horizontal direction and performing parallel processing in a liquid processing tank having two or more lines. In addition to finding that the above has been solved, we have developed a highly efficient and highly accurate automatic liquid treatment line through many accompanying ingenuity. That is,
The present invention is the following (1) to (12).

(1) (a) A setting mechanism for detecting the position and size of an object to be processed conveyed in the horizontal direction and setting it at the racking position, and (b) vertically racking the object to be processed by the setting mechanism. Then, the subsequent automatic liquid processing line and the vertical transfer mechanism for continuously and automatically transferring to the subsequent process, (c) two or more lines provided in parallel to the transfer direction, and liquid processing according to the size of the detected object to be processed. An automatic liquid treatment line comprising a plurality of liquid treatment lines having tanks, and (d) post-processes such as washing, drying, jig removal, and unloading of an object to be treated. (2) The automatic plating line according to (1) above, wherein the liquid treatment is plating and the liquid treatment tank is a plating tank. (3) The automatic etching line according to (1) above, wherein the liquid treatment is etching and the liquid treatment tank is an etching tank.

(4) The automatic liquid processing line as described in (1) to (3) above, wherein the object to be processed is a printed circuit board. (5) To detect the position and size of the object to be processed, one end of the object to be processed is moved to the 0 point on the XY axis, and the length, width, and thickness of the object to be processed are detected and stored by the optical sensor. The automatic liquid treatment line according to any one of (1) to (4) above. (6) The automatic plating line according to (2) above, wherein the jig for vertically racking the object to be plated by the setting mechanism is a jig that also serves as a plating electrode. (7) The automatic plating line according to (2) above, wherein the plating tank provided with two or more lines has a current density added according to the thickness of the object to be plated.

(8) The automatic plating line according to the above (2), wherein the plating tank has a valve for blowing out stirring air and an outlet for discharging electrode residue at the bottom of the anode. (9) The automatic plating line according to (2) above, wherein the anode of the plating tank is a net-shaped tube filled with metal balls. (10) The anode included in the plating tank is of a vertical slide type, and has a shield cover that can slide up and down according to the height of an object to be plated and / or the height of a plating solution, on the anode. (2) The automatic plating line described.

(11) The liquid treatment tank is divided into two or more parts by a partition plate and a partition roll, and the object to be processed can move each of these parts linearly. ) Automatic liquid processing line as described. (12) The voltage loaded on the anode is a positive voltage load time,
The automatic plating line according to (2) above, which has a pulse waveform formed by repeating a load pause and a small negative voltage load time.

The liquid treatment carried out by the apparatus of the present invention is to treat an object to be treated in a liquid, for example, electroplating (JP-A-6-2119), electroless plating, etching, electrodeposition coating, underwater discharge. Processing (Japanese Patent Application No. 6-47170)
No.) or the like for injecting a liquid alone or a gas-liquid mixture onto an object to be processed, for example, liquid injection processing (Japanese Patent Application No. 6-3182).
No. 90), an electric discharge treatment in which a liquid is attached to an object to be treated (Japanese Patent Application No. 6-47170), and the like, but the invention is not limited thereto. Therefore, there is no particular limitation on the object to be processed by the apparatus of the present invention, which is a metal,
Examples include plastics, natural and synthetic inorganic materials, ceramics, glass, semiconductor substrates, wood, various composite materials, and various laminated bodies. Although its shape is not particularly limited, a plate-like material which requires a large space in the conventional batch processing and is difficult to automate the process is preferably applied. Among these, the plating and / or etching treatment on the printed circuit board is particularly preferable. In this case, the printed circuit board has epoxy resin,
A copper-clad laminate such as polyimide or fluororesin, a ceramic substrate, a flexible substrate, etc. are included and are not particularly limited.

FIG. 1 shows an overall conceptual view of the automatic liquid treatment line of the present invention. The pre-processed object is conveyed to the setting mechanism in the horizontal direction. When the object to be processed is a plate-like object such as a printed circuit board, the transfer is usually carried out one by one or in a piled state while being laid down horizontally. The objects to be processed are individually entered into the set mechanism and positioned, and at the same time, various sensors such as an optical sensor are used to vertically and
Lateral, thickness dimensions, etc. are detected and stored for later processing. The object to be processed that has been positioned is racked vertically by, for example, narrowing four corners with a jig that also serves as an electrode. At this time, the lower jig may move on the rail, or the upper jig may hang the object to be processed. From the plurality of parallel lines, the line to be processed is selected based on the previously recorded data such as dimensions, and each processed product is processed in each line. Where each processing line is 1
This includes not only the case where each liquid processing tank is provided, but also the case where a plurality of continuous liquid processing tanks are provided. For example, in the case of plating a printed circuit board, a plating tank having a voltage corresponding to the thickness of the board is selected, or a plating tank having a plating solution having a depth corresponding to the height when the board is placed vertically is selected. . The objects to be processed that have undergone the liquid processing in each line are gathered again to form a single transfer line, which moves to post-processing steps such as cleaning and drying. After this, the object to be processed is laid down sideways and appropriately packed or moved to the next step.

The pretreatment prior to the liquid treatment of the present invention is not particularly limited, and it is usually performed as a pretreatment depending on the type of each material to be treated and the treatment method. For example,
Cutting, washing, drilling, surface polishing, roughening treatment, chemical treatment and the like can be mentioned. If the object to be processed is a printed circuit board in particular, small-diameter holes such as through holes and blind holes, removal of dirt on the inner wall by permanganate for these small-diameter holes, or desmear treatment such as corona discharge treatment, Pre-treatment polishing such as buffing, high pressure / ultrasonic cleaning, hot air drying, and water washing correspond to this. FIG. 2 shows an example of the setting mechanism of the automatic liquid processing line of the present invention. In the setting mechanism, the object 1 to be processed conveyed in the horizontal direction of the arrow from the pretreatment step to the setting mechanism, for example, the printed circuit board provided with a large number of small-diameter holes, has the lateral pressing device 3 and the advancing direction pressing device 4. By this, the arm is moved in the direction perpendicular to the X-axis and the Y-axis to a stopper extending like a diagonal arrow, and the state is changed from the dotted line state to the solid line state. The 0 point on the X-Y axis of the stopper is a reference position for vertical racking, and at the same time, the length, width, and thickness of the object to be processed are detected and stored. The specific means for detecting the size is not particularly limited, but for example, a method of detecting from the stop position of the pressing devices 3 and 4, a setting method for an optical sensor provided in a lattice shape in the X-Y axis direction on the bottom of the setting mechanism. A method of illuminating light from the upper part of the mechanism and detecting vertical and horizontal dimensions by the portion shaded by the object to be processed 1, conversely, providing a light source at the bottom of the setting mechanism,
For example, there is a method of detecting light emitted from small-diameter holes opened in a grid pattern in the axial direction by an optical sensor above the setting mechanism. Further, the thickness of the object to be processed 1 can be detected when sandwiched by a racking jig as described later.
Further, it is possible to irradiate infrared rays and ultrasonic waves from above at the racking position to obtain the thickness from the reflection position, and it is also possible to detect another thickness by pressing another pressing device from above. .

FIG. 3 is a view showing a state in which the object 1 to be processed is racked. The workpiece 1 set at the racking position by the stopper 2 shown in FIG. 2 and having its vertical and horizontal dimensions detected is held using the jigs 5 and 6. The number of jigs and the places to be attached depend on the size and processing method of the object to be processed,
Normally, one jig 5 or 6 is attached to each of the four corners of the workpiece 1. In FIG. 3, four jigs are attached to the corners of the workpiece,
Two jigs 5 among them come to the top when the object 1 is vertically racked, and two jigs 6 come to the bottom when racked. The jigs 5 and 6 press and hold the object to be processed 1 with appropriate strength by the structure of springs and screws. It is also possible to measure the thickness of the object to be processed 1 with this jig. The object to be processed 1 held by the jigs 5 and 6 is racked vertically as shown by the arrow in FIG. 3, and the object to be processed 1 is conveyed to the subsequent processing tank of the liquid processing line. The racking and conveying method is not particularly limited, and there is a method in which the lower jig 6 moves on the rail, and a method in which the upper jig 5 moves while suspending the workpiece 1. In this way, the workpieces 1 vertically racked by the setting mechanism are successively conveyed to the subsequent steps. For example, when the liquid treatment uses an electric current such as plating, all or part of the jig can also serve as an electrode.

The vertically racked workpiece is shown in FIG.
, A plurality of processing lines A, B, ... Which are arranged in parallel are selected and sent. Taking the plating process as an example, the material is sent to a plating tank which is a liquid processing tank having a current density corresponding to the thickness of the object to be processed detected by the setting mechanism. Similarly, the workpiece is sent to a plating tank having a depth corresponding to the vertically racked height of the workpiece. The liquid treatment tank of each line may have a known structure for each treatment method. In order to operate the automatic liquid processing line of the present invention with high efficiency, it is preferable that each liquid processing tank has a tank long in the carrying direction of the object to be processed because continuous processing can be performed while the liquid is being transferred.

FIG. 4 is a plan view showing an example of a plating tank in the case of an electrolytic plating tank and an elevation sectional view taken along the line AA '. The object 1 to be continuously conveyed is a printed circuit board which has already been formed with a large number of small holes and has been desmeared as a pretreatment. A jig 5 also serving as a cathode electrode is fixed to the upper corner of the vertically racked printed circuit board 1, and is suspended and conveyed by the jig 5. The printed circuit board 1 transferred onto the plating tank 7 is vertically lowered into the plating solution 8 and the rail 15 provided at the bottom of the plating tank 7 is provided with the jig 6 provided at the lower corner.
It makes contact with and moves horizontally. Anodes 9 are provided in rows on both sides of the plating tank 7. The material and shape of the anode 9 are not limited to carbon rods, copper rods and the like, but it is preferable that the anode 9 be made of a metal mesh tube and made of copper, phosphorus-added copper or copper alloy balls. A lot of are used. Cu- used for the anode 9
Since an oxide film is formed on the surface of the metal ball such as P by drying, it is preferable to always wet the metal ball with the plating solution in order to prevent this. For this reason, it is effective to suck up the plating liquid surface with a pipe, a pump, or the like, or spray a new plating liquid or a circulating plating liquid onto the upper portion of the cover covered with each anode 9.

In order to perform uniform plating, each anode 9 in both rows can slide up and down according to the size of the object 1 to be processed, and also the upper discharge according to the size of the object 1 to be processed. A cover 10 made of a conductor or an insulator that shields a desired portion of the upper portion of the anode 9 is covered to adjust the area, and the cover 10 also preferably has a mechanism capable of sliding up and down. The material of the conductor or the insulator is not limited, and for example, metal, carbon material, ceramic, glass, plastic and the like are used. As the plating process progresses, the metal balls in the mesh tube of the anode 9 become smaller and move to the lower part of the mesh tube as the volume decreases, so new metal balls are replenished from the upper part as appropriate. In order to perform uniform plating, there is a method of adjusting the voltage to each anode 9 in both rows as shown in FIG. 4, but in addition to this, all anodes 9 are loaded with the same voltage, A method of interrupting the electric current every several lines is effective for equalizing the current density, which is preferable, depending on the processed material. In addition,
Impurities and the like from the metal balls used for the anode 9 become sludge and settle to the bottom of the plating tank. Therefore, the opening / closing plate 13 is provided on the bottom of the tank in the downward direction of the anode 9,
Normally, it is located at the bottom 12 of the plating tank, but it can be opened at the time of cleaning to discharge the sludge together with the waste plating solution, and the sludge can be dropped onto a slope provided further below the plating tank and discharged from the discharge port 14. Further, in order to make the plating on the surface of the printed circuit board 1 uniform, it is also effective to generate bubbles from the air tube 11 during the plating to stir the plating solution. Further, it is possible to circulate the plating solution in order to make it uniform, to perform filtration, replenishment of new plating solution, temperature control of the plating solution, and the like.

FIG. 6 shows a further preferred embodiment of the present invention, in which one row of liquid treatment tanks continuously performs two or more stages of liquid treatment. For example, in an electrolytic plating line, one step of water method, one step of activation treatment with sulfuric acid, two steps of water washing, one to several steps of electroplating, and three steps of water washing are performed. Conventionally, in order to continuously perform such multi-stage liquid treatment, although the treatment tanks are arranged in a line,
When moving an object to be processed between processing tanks, it was temporarily pulled up from the processing tank, moved to the next processing tank, and then processed in the next liquid processing tank. Therefore, there is a limit to the processing efficiency. In the present invention, by partitioning each of these liquid processing tanks with the internal partition plate 16 and the partition roll 17, it is possible to make them continuous as one processing line. In FIG. 6, the object 1 to be processed, which has been vertically tracked and conveyed in a long continuous line of the liquid processing tank 7, is first put in the first processing section. The object 1 to be processed linearly moves in the traveling direction on a rail drawn at the bottom of the processing tank. The first processing section and the second processing section are normally closed by a pair of elastic rollers 17, but when a plate-shaped object to be processed passes, elastic deformation of the rollers and springs supporting the rollers themselves are used. The distance between the rollers is increased by the thickness of the workpiece. Therefore, the treatment liquids are hardly mixed between the adjacent treatment units. Since it is preferable that the material of the roller has little deterioration with respect to the treatment liquid, for example, a molded body of silicon resin or fluororesin, a covering body, or a foamed body of these resins is preferably used.

When the liquid treatment is electrolytic plating treatment, the voltage load on the anode may be generally a positive DC voltage. or,
It is also effective to use a positive voltage with a pulse waveform,
A pulse waveform in which a cycle of a positive voltage load time (τ _on ), a load rest time (τ _off ) and a very small negative voltage load time (τ _minus ) as shown in FIG. 7 is repeated is preferable. By applying such a pulse voltage, electrolytic plating proceeds during a positive voltage load, the electrolytic plating solution is homogenized by convection during a rest of the load, and the impure layer on the plating layer surface is peeled off during a negative voltage load, This has the effect that the electrolytic plating can be uniformly processed by the next positive voltage load.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on Examples. Example Maximum 600 × 600 mm, minimum 200 × as an object to be treated
Glass-impregnated epoxy resin copper-clad laminate of various sizes of 200 mm with a large number of small-diameter holes and a plate thickness of 1.6 to 3 m
m printed circuit board was used. As a pretreatment, the printed circuit board was subjected to corona discharge treatment by a method in which the stain on the inner wall of the through hole was removed by permanganate, and by the method described in Japanese Patent Application No. 6-59135. Further, the surface was buffed and washed with water, and then continuously conveyed horizontally to the setting mechanism shown in FIG. In the setting mechanism, each printed circuit board was positioned at the reference point of the stopper by using a presser, and the vertical and horizontal dimensions were detected from the displacement of the presser and stored. The plate thickness was detected using a measuring gauge when the jig was attached in the setting mechanism. After attaching the jigs that also serve as electrodes to the four corners of the printed circuit board,
Two upper corners were lifted and the entire substrate was vertically racked as shown in FIG.

The plating tank was provided with three lines A to C. The structures of the plating bath and the anode of each line used those shown in FIGS. 4 and 5. Each line is selected according to a large A line to a small C line, for example, 300 ×
Select the A line for 400 mm and the C line for 500 x 600 mm. The current density was automatically changed from 2.5 A / dm ² to 4.0 A / dm ² according to the detected and stored plate thickness, and the air stirring conditions were also changed. As the negative voltage, a pulse wave as shown in FIG. 7 was used. The pulse is positive 25V for 10 microseconds, rest time 1
5 µsec, -5V was repeated for 5 µsec. Moving in the direction of travel due to racking is from 100 mm / min to 610
It can be adjusted up to mm / min, and the movement on the automatic plating line could be 0.3 m / min or more.

Each plating line was washed with water in a first-stage washing tank, then activated in a sulfuric acid tank, further washed in a second-stage washing tank, and then electroplated. The plating solution consists of copper sulfate, sulfuric acid, water, a small amount of brightener and a small amount of other additives. The operating interval of each printed circuit board was set to 50 mm, and the plating liquid surface was adjusted to about 50 mm above the board, but by further moving the cover above the anode up and down, the current was automatically adjusted so that current could flow evenly through the board. After electroplating, the plate was washed with water in a 3-stage washing tank. The printed circuit boards processed in the plating lines A to C were collected again in one line and carried out to the subsequent automatic drying process. The number of steps such as the washing bath and the electrolytic bath set in the above embodiments is not limited, and it is natural that the number is changed depending on the type and size of the object to be treated and the treatment method.

[0021]

As described above, according to the present invention, various liquid treatments can be fully automated, and high-speed continuous treatment and high quality can be achieved. In particular, by devising the plating tank to make the plating process uniform, it is possible to efficiently process many types of substrates.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an automatic liquid processing line of the present invention.

FIG. 2 is a plan view showing a setting mechanism of the present invention.

FIG. 3 is a diagram showing racking and transport at a set position according to the present invention.

FIG. 4 is a plan view and a sectional view showing an embodiment of an electroplating bath applied to the present invention.

5 is a perspective view and a plan view showing an anode used in the electroplating bath of FIG. 4 and a cover thereover;

FIG. 6 is a plan view and a front sectional view of a continuous liquid processing tank,

FIG. 7 is a voltage waveform diagram showing an example of a load of electrolytic plating.

[Explanation of symbols]

 1 Object to be treated 2 Stopper 3 Presser (Y-axis direction) 4 Presser (X-axis direction) 5 Upper jig 6 Lower jig 7 Liquid processing tank 8 Processing liquid 9 Anode 10 Cover 11 Air pipe 12 Plating tank bottom 13 Opening / closing Plate 14 Discharge port 15 Rail 16 Partition plate 17 Partition roller

Claims (12)

[Claims] 1. A set mechanism for (a) detecting a position and a size of an object to be processed conveyed in a horizontal direction and setting the position to a racking position, and (b) vertically racking the object to be processed by a setting mechanism. , A subsequent automatic liquid processing line and a vertical transfer mechanism for automatically transferring continuously to a subsequent step, (c) a liquid processing tank provided with two or more lines parallel to the transfer direction and corresponding to the detected size of the object to be processed. An automatic liquid treatment line, comprising: a plurality of liquid treatment lines each having a plurality of liquid treatment lines, and (d) post-processes such as washing, drying, jig removal, and unloading of an object to be treated. 2. The automatic plating line according to claim 1, wherein the liquid treatment is plating, and the liquid treatment tank is a plating tank. 3. The automatic etching line according to claim 1, wherein the liquid treatment is etching and the liquid treatment tank is an etching tank. 4. The automatic liquid processing line according to claim 1, wherein the object to be processed is a printed circuit board. 5. The position and size of the object to be processed are detected by moving one end of the object to be processed to the 0 point on the XY axis,
5. The automatic liquid treatment line according to claim 1, wherein the width and the thickness are detected and stored by an optical sensor. 6. The automatic plating line according to claim 2, wherein the jig for vertically racking the object to be plated by the setting mechanism is a jig also serving as a plating electrode. 7. The automatic plating line according to claim 2, wherein the plating tank provided with two or more lines has a current density added according to the thickness of the object to be plated. 8. The automatic plating line according to claim 2, wherein the plating tank has a valve for blowing agitation air and an outlet for discharging electrode residue on the lower bottom of the anode. 9. The automatic plating line according to claim 2, wherein the anode of the plating tank is a net-shaped tube filled with metal balls. 10. The plating tank has an anode that is vertically slidable, and a shield cover that can be slid vertically depending on the height of the object to be plated and / or the height of the plating solution is provided on the anode. The automatic plating line according to claim 2. 11. The liquid treatment tank is divided into two or more parts by a partition plate and a partition roll, and the object to be processed can move each of these parts linearly. Automatic liquid processing line. 12. The voltage applied to the anode has a pulse waveform consisting of repetitions of a positive voltage load time, a load rest and a small negative voltage load time.
The described automatic plating line.