JP3091121B2 - Automatic liquid processing line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an automatic liquid processing line suitable for liquid processing of various structural materials and functional materials. In particular, the plating and / or plating of plate-like materials, for example copper-clad laminates
Alternatively, it is preferably applied to etching.

[0002]

2. Description of the Related Art Conventionally, processes for spraying or spraying a liquid include, for example, plating, etching, electrodeposition coating, liquid spraying, underwater discharge treatment, and other surface treatments. It is necessary to efficiently process the workpiece and improve the quality of the processing. In particular, when the object to be processed is a plate-like object, for example, a printed circuit board, a large space is required in each step, and the most important liquid processing step is a rate-determining step, which is a bottleneck for increasing the overall speed. Had become.

[0003]

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

[0004]

Means for Solving the Problems As a result of diligent studies, the inventors of the present invention have found that the object to be processed conveyed in the horizontal direction is vertically racked and parallel-processed in two or more liquid processing tanks. Has been solved, and a number of accompanying ingenuity have led to the development of a more efficient and more accurate automatic liquid processing line. That is,
The present invention is the following (1) to (12).

(1) (a) A setting mechanism for detecting the position and size of a workpiece conveyed in a horizontal direction and setting the workpiece at a racking position, and (b) racking the workpiece vertically by a setting mechanism. And the detected position and dimensions of the workpiece
(C) two or more lines are provided in parallel with the conveyance direction, and are automatically detected by a mechanism for selecting an automatic liquid processing line in accordance with the automatic liquid processing line, and a vertical type conveyance mechanism for automatically and continuously conveying the liquid to a subsequent process. A plurality of liquid processing lines each having a liquid processing tank corresponding to the size of the processed object, and (d) a post-process such as washing, drying, removing a jig, and carrying out the processed object. Processing line. (2) The automatic plating line according to (1), wherein the liquid treatment is plating, and the liquid treatment tank is a plating tank. (3) The automatic etching line according to (1), wherein the liquid processing is etching, and the liquid processing tank is an etching tank.

(4) The automatic liquid processing line according to any one of (1) to (3), wherein the object to be processed is a printed circuit board. (5) To detect the position and size of the object, move one end of the object to the zero point on the XY axis, and detect and store the length, width, and thickness of the object by an optical sensor. The automatic liquid processing line according to any one of the above (1) to (4), wherein (6) The automatic plating line according to (2), 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), wherein the plating tank provided with two or more lines has a current density 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 a discharge port for electrode residue on the lower bottom of the anode. (9) The automatic plating line according to (2), wherein the anode of the plating tank is a net-like cylinder filled with metal balls. (10) The plating tank has an anode that slides up and down, and a shielding cover that can slide up and down in accordance with the height of an object to be plated and / or the height of a plating solution is provided above the anode. (2) The automatic plating line according to (2).

(11) The liquid processing tank is divided into two or more portions by a partition plate and a partition roll, and the object to be processed can move these portions linearly. ) Described automatic liquid processing line. (12) The voltage applied to the anode is a positive voltage load time,
The automatic plating line according to the above (2), which has a pulse waveform composed of a repetition of a load pause and a small negative voltage load time.

The liquid treatment performed by the apparatus of the present invention includes a treatment of an object in a liquid, for example, electroplating (JP-A-6-2119), electroless plating, etching, electrodeposition coating, underwater discharge. Processing (Japanese Patent Application No. 6-47170)
And the like, in which a liquid alone or a gas-liquid mixture is sprayed onto a processing object, for example, a liquid spraying process (Japanese Patent Application No. 6-3182).
No. 90), a discharge treatment in a state where a liquid adheres to an object to be processed (Japanese Patent Application No. 6-47170), but the present invention is not limited thereto. Therefore, there is no particular limitation on the object to be subjected to the liquid treatment in the apparatus of the present invention,
Examples thereof include plastics, natural and synthetic inorganic materials, ceramics, glass, semiconductor substrates, wood, various composite materials, and various laminates. The shape is not particularly limited, but a plate-like material which requires a large space in the conventional batch processing and which has been difficult to automate the process is preferably applied. Of these, plating and / or etching on a printed circuit board is particularly preferred. In this case, the printed circuit board contains epoxy resin,
Examples include, but are not particularly limited to, copper-clad laminates such as polyimide and fluorine resin, ceramic substrates, and flexible substrates.

FIG. 1 is an overall conceptual diagram of an automatic liquid processing line according to the present invention. The preprocessed 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 performed one by one or several times in a state of being laid sideways. At the same time the workpieces enter and set into the setting mechanism, and at the same time, using various sensors such as optical sensors,
Width, thickness dimensions, etc. are detected and stored for later processing. The positioned workpiece is narrowed at four corners by, for example, a jig serving also as an electrode and vertically racked. At this time, the lower jig may move on the rail, or the upper jig may move by suspending the workpiece. A line to be processed is selected from a plurality of parallel lines based on data such as dimensions previously recorded, and each processed object is processed by each line. Here, each processing line is 1
This includes not only a case having a plurality of liquid processing tanks but also a case having a plurality of continuous liquid processing tanks. For example, in the case of plating a printed circuit board, a plating bath having a voltage according to the thickness of the substrate is selected, or a plating bath having a plating solution having a depth corresponding to the height when the substrate is made vertical is selected. . The objects to be processed, which have been subjected to the liquid processing in each line, gather again to form one transport line, and move to a post-processing step such as washing and drying. After that, the object to be processed is laid down sideways and packed or moved to the next step as appropriate.

The pretreatment prior to the liquid treatment of the present invention is not particularly limited, and 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, surface roughening treatment, chemical treatment and the like can be mentioned. The object to be processed, especially in the case of a printed circuit board, is a through-hole, processing of small-diameter holes such as blind holes, removal of dirt on the inner wall of these small-diameter holes by permanganate, or desmear processing such as corona discharge processing, This includes pretreatment polishing such as buffing, high pressure / ultrasonic cleaning, hot air drying, and water washing. FIG. 2 shows an example of the automatic liquid processing line setting mechanism of the present invention. The object 1 to be processed, for example, a printed circuit board provided with a large number of small-diameter holes, conveyed to the setting mechanism in the horizontal direction of the arrow from the pre-processing step is a horizontal pressing device 3 and a traveling pressing device 4 in the setting mechanism. As a result, the arm moves as a diagonal arrow to the stopper whose arm extends in the direction perpendicular to the X axis and the Y axis, and is aligned from the dotted line to the solid line. The zero point on the XY axis of the stopper is a reference position for vertical racking. At the same time, the vertical, horizontal, and thickness of the workpiece are detected and stored. Although the specific means for detecting the dimensions is not particularly limited, for example, a method of detecting from the stop positions of the pressing devices 3 and 4 and a method of setting the optical sensors provided in a lattice shape in the X-Y axis directions at the bottom of the setting mechanism. A method of irradiating light from the upper part of the mechanism and detecting the vertical and horizontal dimensions based on a part shaded by the object 1 to be processed, and conversely, providing a light source at the bottom of the set mechanism,
There is a method in which light coming out of small-diameter holes formed in a lattice shape in the axial direction is detected by an optical sensor provided above the setting mechanism. Further, the thickness of the workpiece 1 can be detected when sandwiched between racking jigs as described later.
In addition, it is also possible to irradiate infrared rays and ultrasonic waves from above at the racking position to obtain the thickness from the reflection position, and to detect the thickness by pressing another pressing device from above. .

FIG. 3 is a view showing a state in which the workpiece 1 is racked. The workpiece 1 which is set at the racking position by the stopper 2 in FIG. 2 and whose vertical and horizontal dimensions have been detected is held by using jigs 5 and 6. The number of jigs and the place where they are attached depend on the size of the workpiece and the processing method.
Usually, one jig 5, 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 of the jigs 5 come to the upper side when the workpiece 1 is vertically racked, and two jigs 6 come to the lower side when racking. The jigs 5 and 6 press and hold the processing target 1 with an appropriate strength by a structure of a spring or a screw. Further, it is also possible to measure the thickness of the workpiece 1 with this jig. The processing object 1 held by the jigs 5 and 6 is vertically racked as shown by the arrow in FIG. 3 and transports the processing object 1 to the processing tank and the subsequent liquid processing lines. The racking and transport method is not particularly limited, and there are 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. The workpieces 1 vertically racked by the setting mechanism are conveyed one after another to the next process. For example, when the liquid processing uses an electric current such as plating, all or a part of the jig can also serve as an electrode.

The workpiece racked vertically is shown in FIG.
Is selected and sent from a plurality of processing lines A, B,... Arranged in parallel. Taking the plating process as an example, the substrate is sent to a plating tank which is a liquid processing tank having a current density corresponding to the thickness of the workpiece 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 processing tank of each line may have a structure known in each processing method. In order to operate the automatic liquid processing line of the present invention with high efficiency, it is preferable that each of the liquid processing tanks has a long tank in the transport direction of the object to be processed, because continuous processing can be performed while transporting.

FIG. 4 is a plan view showing an example of a plating tank in the case of an electrolytic plating tank, and an elevational sectional view taken along the line AA '. The article 1 to be continuously conveyed is a printed circuit board that has been formed with a large number of small-diameter 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 by the jig 5 and transported. The printed circuit board 1 conveyed onto the plating tank 7 is vertically lowered into the plating solution 8 and a rail 15 provided at the bottom of the plating tank 7 is attached to a jig 6 provided at a lower corner.
And proceed in the horizontal direction. Anodes 9 are provided in rows on both sides of the plating tank 7. The material and the shape of the material of the anode 9 are not limited, such as a carbon rod and a copper rod. Preferably, a ball made of copper, phosphorus-added copper or a copper alloy is placed in a tube made of a metal mesh as shown in FIG. Is used. Cu- used for the anode 9
Since the metal ball such as P forms an oxide film on the surface by drying, it is preferable to always wet the metal ball with a plating solution to prevent this. For this reason, it is effective to suck up the plating liquid surface with a pipe, a pump, or the like, and to spray a new plating liquid or a circulating plating liquid on the upper portion of the cover over each anode 9.

In order to perform uniform plating, the anodes 9 in both rows can be slid up and down in accordance with the size of the processing object 1, and the upper discharge can also be performed in accordance with the size of the processing object 1. In order to adjust the part, a cover 10 made of a conductor or an insulator for covering a desired portion of the upper portion of the anode 9 is covered, and it is preferable that the cover 10 also has a mechanism capable of sliding up and down. The material of the conductor or the insulator is not limited, and for example, a metal, a carbon material, ceramic, glass, plastic, or the like is used. As the plating process progresses, the metal balls in the mesh cylinder of the anode 9 become smaller and move to the lower part of the mesh cylinder as the volume decreases, so that 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 of the anodes 9 in both rows as shown in FIG. 4, but in addition to this, the same voltage is applied to all the anodes 9 and the A method of interrupting the current every few lines according to the processed material is effective in making the current density uniform, and is preferable. In addition,
From the metal balls used for the anode 9, impurities and the like become sludge and settle to the bottom of the plating tank. For this purpose, an opening / closing plate 13 is provided below the anode 9 at the bottom of the tank,
Usually, it is located at the position of the bottom 12 of the plating tank, but it can be opened at the time of cleaning to discharge sludge together with the waste plating solution, dropped on a slope provided further below the plating tank, and discharged from the outlet 14. In order to make the plating on the surface of the printed circuit board 1 uniform, it is also effective to generate bubbles during the plating from the air pipe 11 and to stir the plating solution. Further, while the plating solution is circulated to make the plating solution uniform, filtration, replenishment of a new plating solution, temperature control of the plating solution, and the like can be performed.

FIG. 6 shows a further preferred embodiment of the present invention, in which two or more liquid treatments are continuously performed in a single liquid treatment tank. For example, in the electrolytic plating line, the water washing 1 stage 1 stage activation process, two stages of water washing, several stages 1 to electroplating, is possible to perform three-stage water washing has been done with sulfuric acid. Conventionally, in order to continuously perform such multi-stage liquid processing, although each processing tank is arranged in a line,
When an object to be processed is moved between processing tanks, it is once pulled up from the processing tank, moved to the next processing tank, and then processed in the next liquid processing tank. For this reason, the processing efficiency was limited. In the present invention, the partition plate 16 and the partition roll 17 in each of the liquid processing tanks are partitioned by the rolls 17 so that the processing lines can be made continuous as one processing line. In FIG. 6, an object 1 to be processed, which has been vertically tracked and conveyed in a long and continuous line of the liquid processing tank 7, is first put into the first processing section. The workpiece 1 linearly moves in the traveling direction on a rail drawn to the bottom of the processing tank. The first processing unit and the second processing unit are usually closed by a pair of elastic rollers 17, but when a plate-shaped workpiece passes, the elastic deformation of the rollers and the spring supporting the rollers themselves are performed. The distance between the rollers increases by the thickness of the object. Therefore, the processing liquid hardly mixes between the adjacent processing units. Since the material of the roller is preferably a material that does not deteriorate much with respect to the treatment liquid, for example, a molded body or a coated body of a silicone resin or a fluorine resin, or a foam of these resins is preferably used.

When the liquid treatment is an electrolytic plating treatment, the voltage load on the anode may be a DC positive 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 pause time (τ _off ), and a very small negative voltage load time (τ _minus ) as shown in FIG. 7 is preferable. By applying such a pulse voltage, the electrolytic plating proceeds during the positive voltage load, the electrolytic plating solution becomes uniform by convection during the load pause, and the impure layer on the plating layer surface is peeled off during the negative voltage load, There is an effect that uniform processing can be performed to electrolytic plating by the next positive voltage load.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments. Example Maximum 600 × 600 mm, minimum 200 ×
1.6 to 3 m thick, with many small-diameter holes formed in a copper-clad laminate made of glass cloth impregnated epoxy resin with various dimensions of 200 mm
m printed circuit boards were used. As a pretreatment, the printed circuit board was subjected to corona discharge treatment by removing the stain on the inner wall of the through hole with permanganate or by the method described in Japanese Patent Application No. 6-59135. Further, after the surface was buffed and washed with water, it was horizontally and continuously conveyed to a setting mechanism shown in FIG. In the setting mechanism, each printed circuit board was positioned at the reference point of the stopper using a pressing device for each printed circuit board, and the vertical and horizontal dimensions were detected and stored from the displacement amount of the pressing device. The plate thickness was detected using a measuring gauge when the jig was mounted in the setting mechanism. After attaching jigs that also serve as electrodes to the four corners of the printed circuit board,
The 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 tank and the anode in each line were those shown in FIGS. The selection of each line is, for example, 300 × according to the large A line to the small C line.
A line is selected for 400 mm, and C line is selected for 500 × 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 a positive 25 V for 10 μs, a pause 1
5 μs and -5 V were repeated for 5 μs. Movement in the traveling direction by racking is from 100 mm / min to 610
It was adjustable up to mm / min, and the movement in the automatic plating line could be 0.3 m / min or more.

Each plating line was washed with water in a single-stage washing tank, then activated in a sulfuric acid tank, further washed with two-stage washing tank, and then electroplated. The plating solution consists of copper sulfate, sulfuric acid, water, a small amount of brightener and other small amounts of additives. The operating interval of each printed circuit board was set to 50 mm, and the plating liquid level was adjusted to about 50 mm above the board. The cover above the anode was further moved up and down to automatically adjust the current to flow uniformly through the board. After electroplating, the plate was washed with water in a three-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 a subsequent automatic drying step. The number of steps of the washing tank, the electrolytic tank and the like set in the above embodiment is not limited, and it is natural that the number is changed depending on the type and size of the object to be processed and the processing method.

[0021]

As described above, according to the present invention, various kinds of liquid processing can be fully automated, and high-speed continuous processing and high quality can be realized. In particular, various kinds of substrates can be efficiently processed by making the plating process uniform by devising a plating tank.

[Brief description of the 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 conveyance 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 tank applied to the present invention.

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

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]

 DESCRIPTION OF SYMBOLS 1 Workpiece 2 Stopper 3 Presser (Y-axis direction) 4 Presser (X-axis direction) 5 Upper jig 6 Lower jig 7 Liquid treatment tank 8 Treatment 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

──────────────────────────────────────────────────続 き Continued on front page Examiner Masaki Suzuki (58) Field surveyed (Int. Cl. ⁷ , DB name) C25D 19/00, 21/12

Claims (12)

(57) [Claims] 1. A setting mechanism for detecting the position and size of a workpiece conveyed in a horizontal direction and setting the workpiece at a racking position, and (b) vertically racking the workpiece from a setting mechanism. According to the detected position and size of the workpiece
(C) Two or more lines are provided in parallel with the transport direction, and a vertical transport mechanism is provided for automatically transporting the liquid to the subsequent automatic liquid processing line and a subsequent process. Automatic liquid processing comprising: a plurality of liquid processing lines having liquid processing tanks corresponding to the size of the object to be processed; and (d) post-processes such as washing, drying, removing a jig, and carrying out the object to be processed. line. 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 processing is etching, and the liquid processing tank is an etching tank. 4. The automated liquid handling line according to the object to be treated is any one of claims 1 to 3, characterized in that a printed circuit board. 5. The detection of the position and size of the object is performed by moving one end of the object to a zero point on the XY axis,
Horizontal, detected by an optical sensor thickness, automated liquid processing line according to any one of claims 1 to 4, wherein the storing. 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 that also serves as a plating electrode. 7. The automatic plating line according to claim 2, wherein the plating tank provided with two or more lines is provided with a current density 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 out stirring air, and an outlet for discharging electrode residues at a lower bottom of the anode. 9. The automatic plating line according to claim 2, wherein the anode of the plating tank is a net-like cylinder filled with metal balls. 10. An anode included in a plating tank is of a vertical slide type, and a shielding cover slidable up and down according to the height of an object to be plated and / or the height of a plating solution is provided above the anode. The automatic plating line according to claim 2, wherein 11. The liquid processing tank is divided into two or more parts by a partition plate and a partition roll, and an object to be processed can linearly move each of these parts. Automatic liquid processing line. 12. The voltage applied to the anode has a pulse waveform composed of a repetition of a positive voltage load time, a load pause, and a small negative voltage load time.
Automatic plating line as described.