JP2506575B2 - Method and apparatus for producing electrolytic copper foil - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic copper foil manufacturing method and apparatus.

[0002]

2. Description of the Related Art Electrolytic copper foil consists of an insoluble metal anode (anode) and a mirror-polished metal cathode (cathode).
By causing an electrolytic solution to flow between the drum and the drum and applying an electric potential between the anode and cathode drums, copper is electrodeposited on the surface of the cathode drum and the electrodeposit having a predetermined thickness is peeled off from the cathode drum. Manufactured. The resulting copper foil is called raw foil,
After that, various surface treatments are applied to make products for printed circuits and others.

FIG. 5 is an explanatory view showing a positional relationship between a cathode body and an anode in conventional production of electrolytic copper foil. In an electrolytic cell (not shown) that stores an electrolytic solution, the cathode body 1 is installed so as to be rotatable while being partially immersed in the electrolytic solution (here, clockwise). Two anodes 5, for example, two sheets are arranged so as to cover the lower part of the cathode cylinder 1 immersed therein and at a constant distance from the surface of the rotating cylinder. 2 in the electrolyzer
6 o'clock position between the anodes 5 (position of short hand, the same applies below)
The electrolyte is supplied from the electrolyte and the electrolyte flows through the gap between the cathode cylinder and the anode, overflows from the upper edge of the anode, and is circulated. The rectifier 6 maintains a predetermined voltage between the cathode body and the anode.

As the cathode barrel 1 rotates, the thickness of the copper electrodeposited from the electrolytic solution increases, and the raw foil having a predetermined thickness at about 12:00 is peeled off by an appropriate peeling means and wound up.

The green foil produced in this way is
Variations in the thickness occur due to non-uniformity in the distance between the cathodes, the flow rate of the supplied electrolyte, the amount of electricity supplied, and the like.

On the other hand, in an electrolytic copper foil manufacturing facility, after the operation for a certain period of time, the gap between the anode and the cathode becomes uneven due to the wear of the anode, which makes it unusable. In particular, the flow conditions of the electrolytic solution are different between the end portion and the central portion, and the thickness varies in the width direction.

As described above, the electrolytic copper foil produced is shown in FIG.
As shown in, the thickness in the length direction and the thickness in the width direction vary.

However, the variation in the thickness in the lengthwise direction of the electrolytic copper foil has not been considered so far.

On the other hand, in order to achieve a uniform thickness in the width direction of the electrolytic copper foil, the following measures have been conventionally taken: (1) Anode milling: In an electrolytic copper foil manufacturing facility, an anode is used. After the operation for a certain period of time, the wear of the steel causes unevenness between the anode and the cathode, making it unusable.
The state in which it cannot be used means a state in which the electrolytic voltage is abnormally increased or a state in which the thickness of the manufactured copper foil has a large variation. In order to avoid this situation, the surface of the anode used for a certain period is cylindrically processed by a special cutting machine. (2) Partial shaving of the anode: The variation in the thickness in the width direction of the copper foil manufactured after the anodic milling is measured, and the surface of the anode is partially shaved according to the data to correct the thickness of the copper foil.

[0010]

Copper foil is mainly used for printed wiring boards, but with the increase in the density of the printed wiring boards, the width of the circuit is narrowed and the thickness of each layer is reduced, resulting in a decrease in the thickness per layer. With the progress of thinner copper foil, the demand for uniform thickness of copper foil is becoming more and more severe.

[0011] Along with this, the solution of the uniform thickness in the length direction, which has been overlooked, has become a serious problem.

The above-mentioned two conventional methods for making the thickness in the width direction uniform cannot be corrected during operation and cannot cope with the variation in the thickness in the width direction due to uncertain causes other than the anode. However, the partial cutting of the anode is a time-consuming and tedious work, and it is not always easy to obtain the desired effect.

An object of the present invention is to provide a new electrolytic copper foil manufacturing method and a method capable of separately correcting the thickness in the length direction and the width direction during operation, and also capable of correcting these thicknesses due to uncertain causes. It is to develop the device.

[0014]

Means for Solving the Problems The present inventors have constructed at least a part of an anode as a plurality of split anodes for equalizing the thickness, and the amount of electricity supplied to the electrodes for equalizing the thickness is set in the longitudinal thickness. It has been conceived to perform control based on a combination pattern of the pattern of No. 1 and the pattern of thickness in the width direction. To control the amount of electricity, a rectifier that individually controls the amount of electricity supplied to the split anode is installed, or the distance between the split anode and the cathode barrel is individually adjusted to adjust the thickness of the split anode and the cathode barrel. This can be achieved by installing a split anode position adjusting mechanism that individually controls the current density between the two.

Based on this knowledge, the present invention provides (1) an electrolytic solution is flown between a rotatable cathode barrel and at least one anode facing the cathode barrel, and copper is charged on the surface of the cathode barrel. In the method for producing an electro-deposited copper foil, wherein the deposited and electrodeposited copper foil is peeled from the cathode cylinder, at least a part of the anode is configured as a split anode for uniformization of thickness, and supplied to the split anode for uniformization of thickness. An electrolytic copper foil characterized in that the length and width-direction thickness of the copper foil are made uniform by individually controlling the amount of electricity generated based on a combination pattern of the length-direction thickness pattern and the width-direction thickness pattern. And (2) the amount of electricity supplied to the split anodes for uniform thickness is individually controlled based on the combination pattern of the lengthwise thickness pattern and the widthwise thickness pattern of the copper foil per one revolution of the cathode body. Characterized by It provides a method of manufacturing an electrolytic copper foil (1). The present invention also provides (3) an electrolytic solution flown between a rotatable cathode barrel and at least one anode facing the cathode barrel, to cause copper to be electrodeposited on the cathode barrel surface and electrodeposited copper foil. In an apparatus for producing an electrolytic copper foil for peeling from the cathode cylinder, at least a part of the anode is configured as a split anode for uniform thickness, and a combination pattern of a lengthwise thickness pattern and a widthwise thickness pattern is formed. (4) An apparatus for producing an electrolytic copper foil having a uniform length and a width direction thickness, characterized by comprising a rectifier for individually controlling the amount of electricity supplied to the thickness-uniformizing divided anodes based on the above, and (4) Electrolysis in which an electrolytic solution is flown between a rotatable cathode barrel and at least one anode facing the cathode barrel, copper is electrodeposited on the cathode barrel surface, and the electrodeposited copper foil is peeled from the cathode barrel. In the copper foil manufacturing equipment, At least a part of the split anode for uniform thickness is constructed, and the spacing between the split anode for uniform thickness and the cathode cylinder is individually determined based on a combination pattern of a pattern of thickness in the length direction and a pattern of thickness in the width direction. To provide uniformized length and width-direction thickness, which is provided with a split anode position adjusting mechanism for individually controlling the current density between the split uniformizing split anode and the cathode cylinder. An apparatus for producing the electrolytic copper foil having the same is also provided.

[0016]

[Function] In the electrolytic copper foil raw foil, variations in the thickness in the length direction mainly caused by the non-uniformity of the flow rate of the supplied electrolytic solution or the supplied amount of electricity and the cathode body to the anode gap are mainly There is a variation in the width direction due to this. According to the invention,
At least a part of the anode already described in FIG. 5, preferably at least one or a part thereof on the copper foil take-out side is divided into a plurality of thickness-equalizing divided anodes. The length and width-direction thickness of the copper foil are made uniform by individually controlling the amount of electricity supplied to these thickness-uniformizing divided anodes based on the combination pattern of the length-direction thickness pattern and the width-direction thickness pattern. To be done.
Of course, in addition to the existing anode, these split anodes for uniforming the thickness can be installed as auxiliary anodes.

[0017]

EXAMPLES In FIGS. 1 and 2, a part of the two anodes on the side where the copper foil is drawn out is a divided anode for uniform thickness (hereinafter, referred to as
An example configured as a split anode 9) will be shown.

In FIG. 3, the split anode 9 is replaced with the copper foil pull-out side anode 5.
Is an example in which a plurality of columns are provided over the entire area.

FIG. 4 shows an example in which not only the copper foil pull-out side but also a part of the anode on the electrodeposition start side is configured as a split anode.

The larger the number of divisions in the width direction and the number of rows of the divided anodes, the finer the control can be performed, but the production and maintenance are difficult, and the width of the copper foil to be produced and the condition of the electrolytic copper foil production equipment are required. 10-40 per row
The number is usually divided into about 20 to 30 pieces.

The operation mode of the production of electrolytic copper foil will be described with reference to the examples of FIGS. 1 and 2.

In an electrolytic cell (not shown) for storing an electrolytic solution such as a sulfuric acid solution of copper sulfate, the cathode cylinder 1, which is a rotating cylinder made of, for example, stainless steel or titanium, is partially immersed in the electrolytic solution. Here, it is installed by a supporting device so that it can rotate clockwise.

The lower part of the cathode body 1 which has been immersed is covered with a predetermined distance from the surface of the cathode body, for example, 2
A sheet of arc-shaped insoluble anode 5 is arranged. The insoluble anode is made of lead, a lead alloy of lead and antimony, silver, indium, or the like. Alternatively, this insoluble anode is a DS
E or DSA (Dimension StableE)
It may be a structure in which a platinum group metal or its oxide is mainly coated on a valve metal typified by titanium, which is referred to as "lecrode, Anode". The anode is preferably composed of two anode sheets arranged along the lower 1/4 part of the cathode body as shown, but in some cases 1, 3, or 4 It can also be composed of many anode sheets.

According to this example, a part of one of such anodes on the copper foil take-out side is configured as the split anode 9 as described above. An appropriate number of split anodes 9 ',
9 ", ... Is formed.

The distance between the cathode body and the anode is usually 2 to 100 mm.
Is maintained at a fixed position within the range. The smaller the distance, the smaller the amount of electricity, but the more difficult it is to control the film thickness and quality.

The space between the cathode cylinder and the anode forms a flow path for the electrolyte. From 6 o'clock position between the two anodes 5, the electrolytic solution is supplied through a suitable pump (not shown) in the cell, and the electrolytic solution flows to both sides through the gap between the cathode cylinder and the anode so that the upper edge of each anode is reached. It spills from and is circulated.

The rectifier 6 maintains a predetermined voltage between the cathode body and the anode.

As the cathode body 1 rotates, the electrodeposition of copper from the electrolytic solution begins at the position of about 3 o'clock and gradually increases in thickness, and at the position of about 9 o'clock the electrodeposition ends and the predetermined thickness is reached. The raw foil having a predetermined thickness at a position of approximately 12:00 is peeled by an appropriate peeling means and wound.

However, as described above, due to variations in the anode-cathode gap, non-uniformity in the flow rate of the supplied electrolytic solution or the supplied amount of electricity, the thickness of the raw foil in the lengthwise direction and the widthwise direction is locally varied. Fluctuations occur.

According to this embodiment, the thickness of the raw foil in the length direction and the width direction is detected after peeling, and when the variation in the thickness exceeds the allowable value, the pattern of the thickness in the longitudinal direction is formed in the direction of eliminating the variation. The amount of electricity to the divided anode is controlled based on the combination with the pattern in the width direction.

More specifically, it is desirable to first measure the thickness pattern per one revolution of the cathode cylinder in advance and then control the amount of electricity to the divided anodes based on this pattern.

In the present invention, the pattern of the thickness per one revolution of the cathode cylinder means that the copper foil produced when the cathode cylinder makes one revolution is divided into, for example, 36 in the length direction and 20 places in the width direction. The thickness of the copper foil at 36 × 20 = 720 is measured, and the state of fluctuation (variation) of the thickness at 720 is shown. This is the pattern of the thickness in the length direction and the pattern of the thickness in the width direction. It shows the combination.

Although the variation in the thickness of the copper foil decreases as the number of divisions in the length direction and the width direction increases, it is usually preferably 10 to 40 in consideration of maintenance of the control device for this purpose.

Hereinafter, the case where the thickness of the copper foil at 720 points is measured in advance as described above will be described.

The thickness variation (variation) at 720 locations is
As described above, it represents the thickness variation due to the non-uniformity of the gap between the cathode and the anode, the flow rate of the supplied electrolytic solution, the supplied amount of electricity, etc. When considering the trajectory of a specific part, it indirectly indicates the relationship with the anode (gap, flow rate of the supplied electrolyte, fluctuations in the supplied amount of electricity, etc.) while the specific part makes a circuit. As a result, the thickness variation is displayed.

Therefore, in order to make the thickness uniform, it is sufficient to determine and control the amount of electricity to each divided anode in accordance with the variation pattern of the thickness at 720 places. Then, the thickness of the raw foil produced during operation is measured, and when fluctuations beyond the allowable range occur, both the length and width directions are controlled by controlling the quantity of electricity in the part corresponding to the fluctuation pattern. Raw foil with a uniform thickness can be obtained.

Although it is considered that this divided anode may normally be provided in one stage, if it cannot be controlled in one stage or if more precise control is required, a plurality of stages or multiple stages may be provided.

A sub-rectifier 7 is connected between the individual split anodes 9 and the cathode cylinder so as to allow individual control of the split anodes 9.

The thickness of the copper foil at each position in the length and width directions can be easily measured by measuring the weight per unit area by appropriate sampling. The device can be arranged in the winding path to monitor the thickness, and a feedback device can be used to interlock with the child rectifier 7.

An insulating seal is preferably provided between the divided anodes. As the insulating seal material, a PVC plate, room temperature vulcanized rubber (RTV: product name), or the like can be used. In addition to this, for example, it is provided by bonding adjacent divided anodes with an insulating adhesive or by integrating the divided anodes with an insulating film interposed therebetween.

According to the invention, the individual control of the split anodes can also be carried out by controlling their respective set positions. Apart from the supporting device for supporting the anode in the electrolyte, means are provided for individually supporting the split anodes and for bringing the individual split anodes closer to or further from the cathode cylinder. These divided anodes are moved back and forth by an appropriate position adjusting mechanism such as a screw mechanism and a piston-cylinder mechanism. The support rod of the specific divided anode corresponding to the specific portion is displaced by the position adjusting mechanism. The current density increases and the thickness of the electrodeposited copper increases as the split anode approaches the cathode cylinder. On the contrary, as the split anode is separated from the cathode body, the current density decreases and the electrodeposited copper thickness decreases.

Thus, according to the present invention, the thickness of the electrolytic copper foil produced by separately controlling the amount of electricity supplied to the divided anodes by using the divided anodes or individually controlling the set positions thereof can be set. It can be made uniform.

(Example 1) Diameter 2.0 m and width 1.3 m
And a cathode having a width of 1.3 m arranged along the lower half of the cathode as shown in the figure to produce a copper foil having a thickness of 35 μm using a copper sulfate solution. I did.
As the anode structure according to the present invention, the structure shown in FIGS. 1 and 2 was used, and the split anode was composed of 20 split anodes.

Then, a pattern of the thickness in the length direction and the width direction per one circumference of the cathode cylinder measured in advance (width direction: 20 ×
Based on the combination of length direction: 36 = 720), each anode was adjusted in the range of 0.1 to 10 A / dm ² using a personal computer. As a result, the thickness variation in the lengthwise direction was reduced by the method of the present invention, and it was possible to reduce from the conventional variation of about 3% to the variation of 0.5% or less.

(Embodiment 2) As an anode constitution according to the present invention, 2 is formed on the existing anode on the side of drawing out the copper foil shown in FIG.
A copper foil having a thickness of 35 μm was manufactured in the same manner as in Example 1 by arranging a divided anode composed of zero divided anodes. The variation in the thickness of the obtained copper foil in the length direction was 0.5% or less.

[0046]

EFFECTS OF THE INVENTION Conventionally, it has not been considered so much.
Simultaneously reduces the variation in thickness in the width direction mainly due to the cathode cylinder-anode gap together with the variation in thickness in the length direction due to the non-uniformity of the flow velocity of the supplied electrolyte or the amount of electricity supplied. Was successful. Regarding the variation in thickness in the width direction, the conventional method requires several anode corrections (partial shaving) to obtain an ideal foil thickness, and it takes about 1 to 2 weeks between corrections. Since there are operating periods,
It took 3-4 weeks to complete the correction,
According to the present invention, the thickness can be adjusted even during the operation, and the copper foil having a good foil thickness can be manufactured. Further, since the partial removal of the anode, which has been conventionally performed every time the anode is replaced, can be eliminated or significantly reduced, various burdens associated with the maintenance of the equipment are significantly reduced.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an arrangement relationship between a cathode cylinder and an anode in an example in which a part of the two anodes on a copper foil drawing side is configured as a split anode.

2 is a perspective view of the anode of FIG. 1. FIG.

FIG. 3 is a perspective view of an anode of a specific example in which the entire copper foil lead-out side anode of FIG. 2 is configured as a plurality of rows of divided anodes.

FIG. 4 shows an example in which a part of the electrodeposition side anode is also configured as a split anode.

FIG. 5 is an explanatory view showing a positional relationship between a cathode body and an anode in conventional production of electrolytic copper foil.

[Description of sign]

 1 Cathode barrel 2 Center axis 4 Outer peripheral wall 5 Anode 6 Rectifier 7 Child rectifier 9 Split anode

Claims (4)

(57) [Claims] 1. An electrolytic solution is caused to flow between a rotatable cathode body and at least one anode facing the cathode body, copper is electrodeposited on the surface of the cathode body, and an electrodeposited copper foil is applied to the cathode. In the method for producing an electrolytic copper foil peeled from a cylinder, at least a part of the anode is configured as a thickness-uniformizing split anode, and the amount of electricity supplied to the thickness-equalizing split anode is a pattern of lengthwise thickness. A method for producing an electrolytic copper foil, characterized in that the length and the width-direction thickness of the copper foil are made uniform by individually controlling based on a combination pattern with a width-direction thickness pattern. 2. The amount of electricity supplied to the divided anodes for uniform thickness is individually controlled based on a combination pattern of a lengthwise thickness pattern and a widthwise thickness pattern of the copper foil per one revolution of the cathode body. The method for producing an electrolytic copper foil according to claim 1, wherein 3. An electrolytic solution is flown between a rotatable cathode body and at least one anode facing the cathode body, copper is electrodeposited on the surface of the cathode body, and an electrodeposited copper foil is applied to the cathode. In an apparatus for producing an electrolytic copper foil peeled from a body, at least a part of the anode is configured as a thickness-uniformizing divided anode, and based on a combination pattern of a lengthwise thickness pattern and a widthwise thickness pattern. An apparatus for producing an electrolytic copper foil having a uniform length and width in the width direction, comprising a rectifier for individually controlling the amount of electricity supplied to the divided anodes for equalizing the thickness. 4. A rotatable cathode barrel and facing the cathode barrel.
An electrolyte solution is caused to flow between at least one anode and the cathode cylinder.
Electrodeposit copper on the surface and deposit the electrodeposited copper foil from the cathode barrel.
In an electrolytic copper foil manufacturing apparatus for peeling,
At least a part of it is configured as a split anode for uniform thickness.
Between the lengthwise thickness pattern and the widthwise thickness pattern
Based on the combination pattern, the split anode and the cathode for uniformizing the thickness
The distance from the polar cylinder is adjusted individually to make the thickness uniform.
Split anode with independent control of current density between the pole and cathode body
Uniformized length characterized by a position adjustment mechanism
An apparatus for producing an electrolytic copper foil having a thickness and a thickness in the width direction .