JPH0436494A - Device for producing electrolytic copper foil - Google Patents

Abstract

PURPOSE:To produce the high-quality electrolytic copper foil uniform in thickness in its cross and longitudinal directions, by forming an anode confronted with a cathode drum as plural thickness uniformizing anodes split in the cross direction and controlling their set positions. CONSTITUTION:A cathode drum 1 as a rotary cylinder is partially dipped in an electrolyte and confronted with at least one circular anode 3. A part of one anode 3 on the copper foil discharge side is formed as a foil thickness uniformizing split anode 4. An electrolyte is supplied to the passage between the drum 1 and the anodes 3 and 4, and a specified voltage is maintained by a rectifier 5. As the drum 1 rotates, copper is electrodeposited from the electrolyte, and the crude foil in specified thickness is released by an appropriate releasing means and wound up. The set positions of the discrete foil thickness uniformizing split anodes 4 are separately controlled. Consequently, the electrolytic current density is adjusted, and the thickness of the electrolytic copper foil produced is uniformized.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an apparatus for manufacturing electrolytic copper foil, and in particular, a dividing device for making the thickness of the electrolytic copper foil uniform so that the thickness of the electrolytic copper foil produced is uniform. The present invention relates to an apparatus for producing electrolytic copper foil, characterized in that an anode is provided and means is provided for individually controlling the setting positions of divided anodes for making the foil thickness uniform. According to the present invention, a high quality electrolytic copper foil having a uniform thickness in the width direction and the length direction can be obtained.

(Prior art) Electrolytic copper foil is produced by flowing an electrolytic solution between an anode made of an insoluble metal and a cathode drum made of a metal whose surface is polished to a mirror finish, and then creating an electric potential between the anode and the cathode drum. It is produced by depositing copper on the surface of the cathode shell and peeling off the electrodeposited material to a predetermined thickness from the cathode shell. The resulting copper foil is called main reinforcement, and is then subjected to various surface treatments to be made into products.

In an electrolytic copper foil production facility, after the anode has been operated for a certain period of time, the distance between the anode and the cathode becomes uneven, especially due to wear and tear, and the equipment becomes unusable. In particular, variations in thickness occur in the width direction. FIG. 8 is an explanatory diagram showing the arrangement 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 rotate while being partially immersed in the electrolytic solution (here, clockwise).

For example, two anodes 3 are disposed to cover approximately the immersed lower half of the cathode barrel 1 and at a constant distance from the surface of the rotating barrel. In the electrolytic cell, electrolyte is supplied from the 6 o'clock position (the position of the hour hand, the same applies hereinafter) between the two anodes 3, and the electrolyte flows through the gap between the cathode body and the anode and from the upper edge of the anode. It gets wet and gets circulated. A rectifier 5 maintains a predetermined voltage between the cathode shell and the anode.

As the cathode body 1 rotates, the thickness of the copper electrodeposited from the electrolytic solution increases, and at approximately the 12 o'clock position, the main strip having a predetermined thickness is peeled off by an appropriate peeling means and wound up.

The anode is locally depleted during use. As a result, the distance between the cathode body and the anode varies, and the thickness of the main bars produced varies in the width direction, as shown in FIG.

One of the important quality requirements for electrolytic copper foil is uniformity of thickness in the width direction.

In order to achieve uniformity in the thickness of electrolytic copper foil in the width direction, conventional measures have been widely taken.

(1) Anode milling: In electrolytic copper foil production equipment, after a certain period of operation, the anode becomes unusable due to wear and tear and unevenness occurs between the anode and cathode.

A state that cannot be used refers to a state in which the electrolytic voltage has increased abnormally or a state in which the thickness of the manufactured copper foil has large variations. To avoid this situation, the surface of anodes that have been used for a certain period of time is machined into a cylinder using a special cutting machine.

(2) Partially scraping the anode After near-node milling, the thickness variation in the width direction of the copper foil manufactured is measured, and according to the data, the surface of the anode is partially scraped to correct the thickness of the copper foil.

(Problems to be Solved by the Invention) The above two conventional countermeasures are the inability to make corrections during operation, the variation in thickness in the width direction due to uncertain causes other than the anode, and the variation in thickness due to the cathode body, for example. , it has disadvantages such as not being able to deal with variations in thickness due to changes in the flow of the electrolyte or unevenness, shaving the anode part is a time-consuming and troublesome process, and it is not always easy to achieve the desired effect. .

The object of the present invention is to develop a new electrolytic copper foil manufacturing apparatus that enables thickness correction during operation, especially thickness correction in the width direction, and also enables thickness correction due to uncertain causes other than the anode. be.

(Means for Solving the Problem) The present inventors configured at least a portion of the anode as a plurality of foil thickness equalizing anodes divided in the width direction, so that the thickness of the electrolytic copper foil in the width direction is uniform. We came up with the idea of individually controlling the divided anodes for thickness uniformity. As a control device,
It has been found that it is better to individually control the setting positions of the divided anodes for uniformizing the foil thickness.

Based on this knowledge, the present invention provides a rotatable cathode shell,
comprising one anode facing the cathode body,
In an electrolytic copper foil manufacturing apparatus that flows an electrolytic solution between the cathode body and the anode, electrodeposit copper on the surface of the cathode body, and peel the electrodeposited copper foil from the cathode body, at least one of the anodes An electrolytic copper foil comprising a plurality of foil thickness equalizing anodes divided in the width direction, and a means for individually controlling the setting positions of the foil thickness equalizing divided anodes. We provide manufacturing equipment for

(Description of Examples) According to the present invention, the anode already described in FIG.
At least a portion, preferably at least one sheet on the copper foil extraction side or a portion thereof, is configured as a plurality of divided anodes for equalizing the foil thickness divided in the width direction. Of course, it is also possible to install a split anode as an auxiliary anode in addition to the existing anode.

FIGS. 1 and 2 show an example in which a part of the copper foil protruding side of the two anodes is configured as a divided anode for uniformizing the foil thickness.

FIG. 3 shows an example in which not only the copper foil draw-out side but also a part of the anode on the electrodeposition start side is configured as a divided anode for making the foil thickness uniform. Control is performed both at the start of electrodeposition and at the end of electrodeposition.

FIG. 4 shows an example in which one of the two anodes on the copper foil extraction side is configured as a divided anode for equalizing the foil thickness by being divided over its entire length.

The larger the number of divisions, the more finely controlled the control, but the more difficult it is to manufacture and maintain, and the number of divisions varies from 10 to 40 pieces, usually 20 to 30 pieces, depending on the width of the copper foil to be manufactured and the status of the electrolytic copper foil manufacturing equipment. It is divided into front and back.

Furthermore, depending on the electrolytic copper foil manufacturing equipment, there may be a tendency for the thickness to fluctuate significantly, for example, the central part of the copper foil may become particularly thin, or conversely, at least one end thereof may become particularly thin. To deal with such cases, the anode
Preferably, at least one sheet of copper foil or a part thereof on the copper foil extraction side is closely spaced in the center or at the side edges and at the side edges in order to more closely control the thickness in the center or at least at one end. Alternatively, it is also convenient to configure the anode as a plurality of divided anodes for equalizing the foil thickness by making the center part sparse and dividing the anode in the width direction.

Figure 5 shows an example in which only the central part of one sheet on the extraction side of the copper foil is configured as a divided anode for equalizing the foil thickness, and Figure 6 shows an example in which only the both end portions are configured as divided anodes for equalizing the foil thickness. Here is an example. It goes without saying that in FIGS. 5 and 6, the divided anode may be a part of the anode, and in FIG. 6, either one may be used. Which one to adopt?
Selection is made depending on the circumstances of the specific copper foil manufacturing equipment.

The operating mode of producing electrolytic copper foil using the apparatus of the present invention will be explained using the examples shown in FIGS. 1 and 2.

In an electrolytic cell (not shown) containing an electrolytic solution, such as a sulfuric acid solution of copper sulfate, a rotating cylindrical cathode body 1, for example made of stainless steel or titanium, is partially immersed in the electrolyte, here a clock It is mounted by a support device so that it can be rotated in any direction. For example, two circular arc-shaped insoluble anodes 3 are disposed to cover approximately the immersed lower half of the cathode barrel l and spaced apart from the surface of the cathode barrel at a constant distance. The anode is
It is made from lead, a lead alloy of lead and antimony, silver, indium, etc. Alternatively, the anode is a DSE or D S
A (Dimension 5table Elec
trode.

It has a structure in which a valve metal such as titanium is coated with mainly a platinum group metal or its oxide. The anode preferably consists of two anode sheets disposed along approximately the lower quarter of the cathode barrel as shown, but in some cases one
It is also possible to construct more anode sheets, such as one, three or four anode sheets. It is possible to slightly adjust the position of the anode relative to the cathode barrel.

According to this embodiment, one part of the copper foil removal pressure side of the anode is
A part of the sheet is configured as the divided anode 4 for making the foil thickness uniform as described above. Appropriate number of divided anodes 4°, 4”
, 4″″, . . . are formed.

The spacing between the cathode body and the anode is typically maintained at a constant position in the range of 2 to 1 oans. The narrower the spacing, the less electricity is required, but it becomes more difficult to control film thickness and quality.

The gap between the cathode body and the anode forms a flow path for the electrolyte. Electrolyte is supplied from the 6 o'clock position between anodes 3 and 4 through a suitable pump (not shown) in the bath, and the electrolyte flows to both sides through the gap between the cathode body and the anode to the upper edge of each anode. It is heated and pressurized and circulated.

A rectifier 5 maintains a predetermined voltage between the cathode shell and the anode.

As the cathode body 1 rotates, the electrodeposition of copper from the electrolyte is
It starts at the 3 o'clock position and gradually increases in thickness until it reaches the 9 o'clock position.
At the o'clock position, the electrodeposition is completed to a predetermined thickness, and at approximately the 12 o'clock position, the main cylinder, which has a predetermined thickness, is peeled off by an appropriate peeling means and wound up. The anode is
In particular, lead-based anodes are locally worn out during use. Therefore,
The spacing between the cathode body and the anode varies. In addition, variations in thickness may occur due to the cathode body, and a certain deflection or flow irregularity of the electrolytic solution may occur. Together, these tend to cause local variations in the thickness of the main cylinder as shown in FIG.

According to the present invention, when the thickness of the main cylinder in the width direction is detected after peeling and the variation in thickness exceeds an allowable value, the setting position of a specific divided anode 4 corresponding to a specific portion in the width direction is set to eliminate the variation. Directions are individually controlled.

The thickness at each position in the width direction of the copper foil can be easily measured by measuring the weight per unit area through appropriate sampling, or by winding up a thickness measuring device such as a capacitance sensing type. It can also be placed in the path to monitor the thickness and linked to the child rectifier 7 using a feedback device.

An insulating seal is preferably provided between each segmented anode. As insulation materials, PVC board, room temperature vulcanized rubber (RTV:
Product name) etc. can be used. In addition to this, it can also be achieved, for example, by joining adjacent divided anodes with an insulating adhesive or by integrating the divided anodes with an insulating film in between.

According to the invention, the individual control of the divided anodes for equalizing the foil thickness is carried out by controlling the respective set positions. Separately from the support device that supports the anode 3 in the electrolyte,
Means are provided for individually supporting the segmented anodes 4 and for moving the individual segmented anodes towards or away from the cathode layer.

FIG. 7a shows the support rods 8° attached to the individual anodes 4°, 4", 4"", etc. of the divided anode 4 corresponding to FIG.
, 8'', 8'''... are shown. The support rod 8 is moved back and forth by an appropriate position adjustment mechanism such as a screw mechanism or a piston-cylinder mechanism.

One specific example is shown in FIG. 7b. A screw block 10 is fixed to each divided anode 4, and a terminal bar 12 is screwed into the block 10. The terminal rod 12 is connected to a connecting rod 18 via two articulated joints 14 and 16, and the connecting rod 18 is rotated by a suitable motor. The use of two articulation joints allows the connecting rod to be placed in the appropriate position above the electrolyte of the electrolytic cell. The rotation of the motor causes the terminal bar 12 to rotate, allowing the block 10 to be moved back and forth. Of course, the block 10 may be connected to a cylinder piston that is movable back and forth.

When supporting relatively heavy full-length divided pieces as shown in FIG. 4, it may be preferable to raise and lower blocks supporting the individual divided pieces using an appropriate lifting device installed at the bottom of the electrolytic cell.

When the thickness variation in the width direction exceeds an allowable value, the support rod 8 of a specific divided anode 4 corresponding to the specific portion in that direction is displaced by the position adjustment mechanism. As the segmented anode approaches the cathode layer, the current density increases and the thickness of the electrodeposited copper increases. Conversely, as the segmented anode is separated from the cathode layer, the current density decreases and the thickness of the electrodeposited copper decreases.

According to the present invention, the thickness of the produced electrolytic copper foil can be made uniform by using the divided anodes for making the foil thickness uniform and individually controlling the setting positions thereof.

Next, an example of use of the device of the present invention will be shown.

(Example 1) Using a cathode layer with a diameter of 2.0 m and a width of 1.3 m, and two anodes with a width of 1.3 m disposed along approximately the lower half of the cathode layer as shown. 35μ thick using copper sulfate solution
m copper foil was manufactured. As the anode structure according to the present invention, the structure shown in FIGS. 1 and 2 was used, and it was composed of 20 divided anodes. The weight per unit area of the peeled copper foil was measured and the thickness of each anode was adjusted within a range of 2 to 50 mm.

As a result, with the device of the present invention, the variation in thickness in the width direction was reduced from the conventional variation of about 3% to 0.5% or less.

(Example 2) The anode structure according to the present invention is constructed by arranging 20 divided anodes on the existing anode on the drawer side of the copper foil shown in FIG. A copper foil with a thickness of 35 μm was manufactured. The variation in the thickness of the obtained copper foil in the width direction is
It was 0.5% or less.

(Effects of the invention) 1. Conventionally, several anode corrections (partial scraping) were required to obtain the ideal foil thickness. Since there is an operating period of about 1 to 2 weeks between corrections, it used to take 3 to 4 weeks to complete the correction, but with the present invention, it is now possible to adjust the thickness even during operation. It has become possible to manufacture copper foil with good thickness.

2. The need to scrape the anode part, which was conventionally performed every time the anode was replaced, is eliminated or significantly reduced, so various burdens associated with equipment maintenance are reduced.

3. Furthermore, the device of the present invention makes it possible to correct variations in thickness in the longitudinal direction, which was previously impossible. Although the variation in the thickness in the length direction is caused by the structure of the cathode shell, it has periodicity and can be corrected by controlling the current conditions according to the present invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing the arrangement relationship between the cathode body and the anode in an embodiment in which a part of the anode on the copper foil drawer side of the two anodes is configured as a divided anode for equalizing the foil thickness. be. 2 is a perspective view of the anode of FIG. 1; FIG. FIG. 3 shows an example in which not only the copper foil draw-out side but also a part of the anode on the electrodeposition start side is configured as a divided anode for making the foil thickness uniform. FIG. 4 shows a configuration example in which the entire length of one of the two anodes on the copper foil extraction side is divided. FIG. 5 shows an example in which only the center portion of one sheet on the copper foil extraction side is configured as a divided anode. FIG. 6 shows an example in which only both ends of the anode are configured as split anodes for making the foil thickness uniform. FIGS. 7a and 7b illustrate the individual control of the set position of the divided anode for foil thickness equalization according to the invention in connection with the example of FIG. 1. FIG. FIG. 8 is an explanatory diagram showing the arrangement relationship between a cathode body and an anode in conventional production of electrolytic copper foil. l: Cathode body 3: Anode 4: Split anode 8: Support rod 10 Ni block 12: vA child rod 14.16: Joint joint 18: Connecting rod Fig. 1 Fig. 3 Fig. 2 Fig. 4 Fig. 7b Fig.

Claims (1)

[Claims] 1) It is equipped with a rotatable cathode shell and at least one anode facing the cathode shell, an electrolyte is flowed between the cathode shell and the anode, copper is electrodeposited on the surface of the cathode shell, and In an electrolytic copper foil manufacturing apparatus that peels electrodeposited copper foil from the cathode body, at least a portion of the anode is configured as a plurality of foil thickness equalizing anodes divided in the width direction, and the foil thickness is An apparatus for manufacturing electrolytic copper foil, characterized in that it is provided with means for individually controlling the setting positions of divided anodes for uniformization.