JPH0436492A - Device for producing electrolytic copper foil - Google Patents

Abstract

PURPOSE:To obtain the high-quality electrolytic copper foil uniform in thickness in its cross and longitudinal directions, by forming an anode as the plural foil thickness uniformizing anodes densely split at the center and separately controlling the quantity of electricity to be supplied to each anode. CONSTITUTION:A cathode drum 1 as a rotary cylinder is partially dipped in an electrolyte and confronted with at least one circular anode 3. One anode 3 thus formed on the copper foil discharge side is densely split at the center and coarsely split at the side ends to obtain 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 between both electrodes by a rectifier 5. As the drum 3 rotates, copper is deposited from the electrolyte, and the crude foil in specified thickness is released by an appropriate releasing means and wound up. In this case, a slave rectifier 7 is connected between the discrete split anodes 4 and the drum 1 to separately control the quantity of electricity to be supplied to each anode, and the thickness of electrolytic copper foil produced is uniformized.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to an apparatus for manufacturing electrolytic copper foil. An electrolysis device characterized in that a divided anode for making the foil thickness uniform is arranged in which the side end portions are sparsely divided in the width direction, and a means is provided for individually controlling the amount of electricity supplied to the divided anode for making the foil thickness uniform. This invention relates to copper foil manufacturing equipment. 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 electrodepositing copper on the surface of the cathode shell, and peeling off the electrodeposited material from the cathode shell once it has reached a predetermined thickness. The resulting copper foil is called the main tube, and is then subjected to various surface treatments and 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. 3 is an explanatory diagram showing the arrangement relationship between a cathode body and an anode in conventional electrolytic copper foil production.

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 cylinder I rotates, the thickness of the copper electrodeposited from the electrolyte increases, and at approximately the 12 o'clock position, the main cylinder, which has reached a predetermined thickness, is peeled off by an appropriate peeling means and wound up.

The anode is locally depleted during use. Therefore, the distance between the cathode body and the anode varies, and the thickness of the resulting main cylinder varies in the width direction, as shown in FIG.

In particular, depending on the electrolytic copper foil production equipment, as a tendency for its wear, for example, as shown in Fig. There are situations in which it is necessary to particularly carefully modify the copper foil.One of the important quality requirements for electrolytic copper foil is uniformity of the 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 produce a new electrolytic copper foil that enables thickness correction during operation, especially careful thickness correction at the center in the width direction, and also enables thickness correction due to uncertain causes other than the anode. The goal is to develop a device.

(Means for Solving the Problems) The present inventors configured at least one of the anodes as a plurality of foil thickness equalizing anodes divided in the width direction, and in this case, the thickness of the central portion was particularly carefully corrected. In order to achieve this goal, we conceived the idea of dividing the central part into dense parts and the side parts into sparse parts, and individually controlling the divided anodes for making the thickness uniform. The amount of electricity supplied to the divided auxiliary anodes for equalizing the foil thickness is individually controlled.

Based on this knowledge, the present invention provides a rotatable cathode shell,
at least one anode facing the cathode body,
In an apparatus for producing electrolytic copper foil, in which an electrolytic solution is flowed between the cathode body and the anode, copper is electrodeposited on the surface of the cathode body, and the electrodeposited copper foil is peeled off from the cathode body, at least One sheet is configured as a plurality of foil thickness equalizing anodes divided in the width direction, densely in the center and sparsely in the side edges, and the amount of electricity supplied to each of the foil thickness equalizing divided anodes is individually divided. Provided is an apparatus for producing electrolytic copper foil, characterized in that it is equipped with a means for controlling.

(Description of Embodiments) According to the present invention, one of the anodes already described in FIG.
The anodes are configured as a plurality of divided anodes for equalizing the foil thickness, preferably at least the one on the copper foil extraction side, which is tightly divided in the center and the side edges are sparsely divided in the width direction. Depending on the electrolytic copper foil manufacturing equipment, the tendency of the equipment to wear out may be such that the thickness of the copper foil varies greatly, for example, the central part of the copper foil becomes particularly thin. In order to cope with such a case, it may be more convenient to divide the anode in the width direction, with the central part being densely divided and the side edges being sparsely, rather than having the entire anode divided equally. The present invention meets these needs.

FIGS. 1 and 2 show the simplest example in which only the central part of the anode on the side where the copper foil protrudes out of two anodes is a split anode. It is also possible to adopt a structure in which the center part is divided into a larger number of parts, and the side parts are divided into fewer parts. For example, the center part is 3~
20 pieces, and the side edges can be divided into 1 to 5 pieces. The key is to finely control the amount of electrodeposition in the central area where the thickness fluctuates rapidly (
It should be possible to fix it.

The larger the number of divisions, the more finely controlled the control, but the more difficult it is to manufacture and maintain, so the number is selected as appropriate depending on the width of the copper foil to be manufactured and the condition of the electrolytic copper foil manufacturing equipment.

To explain the operation mode of producing electrolytic copper foil using the apparatus of the present invention, an electrolytic tank (
(not shown), the cathode side 1, which is a rotating cylinder, for example made of stainless steel or titanium, is partially immersed in the electrolyte and is here mounted by means of a support device so as to rotate clockwise. For example, two arc-shaped insoluble anodes 3 are disposed to cover approximately the immersed lower half of the cathode side 1 and at a constant distance from the surface of the cathode body.

The anode is also supported in the electrolyte by a suitable device,
It is possible to slightly adjust the position relative to the cathode side. 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 5tableElect
It may have a structure in which a valve metal typified by titanium is coated mainly with a platinum group metal or its oxide, which is called a metal rod or anode. The anode preferably consists of two anode sheets disposed along approximately the lower quarter of the cathode side as shown, but in some cases more such as one, three or four sheets may be used. It can also be constructed from multiple anode sheets.

According to the present invention, preferably at least one of the anodes on the copper foil extraction side is used as the divided anode 4 for equalizing the foil thickness, which is divided in the width direction, with the center portion being densely divided and the side edges being sparsely divided in the width direction. configured.

In this specific example, four divided anodes 4"4" and 4" are placed in the center.
"'4""° is formed and each side edge is left in one piece.

The distance between the cathode side and the anode is usually maintained at a constant position within a range of 2 to 100 mm. 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 side 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 tank, and the electrolyte flows to both sides through the gap between the cathode side 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 and the anode.

As the cathode side 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 distance between the cathode side and the anode varies. In addition, variations in thickness may occur due to the cathode side, and a certain deflection or flow irregularity of the electrolytic solution may occur. Together, these can lead to variations in thickness, usually a decrease, particularly in the center of the main reinforcement, such as that shown in FIG. 3, for example.

According to the present invention, the thickness of the main reinforcing bars in the width direction is detected after peeling, and when the thickness variation exceeds an allowable value, the split anode 4
are individually controlled to eliminate variations in supply. In order to enable individual control of the segmented anodes 4, a child rectifier 7 is connected between the individual segmented anodes 4 and the cathode shell as means for individually controlling the quantity of electricity. 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 an electrostatic detection 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. Insulating materials include 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.

In this way, by using the device of the present invention, the thickness of the electrolytic copper foil manufactured by using the divided anode for uniformizing the foil thickness, which is densely divided in the center, and individually controlling the amount of electricity supplied thereto. can be made uniform.

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

Diameter 2. Using a copper sulfate solution using a cathode body with 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 body as shown, 35μ
m copper foil was manufactured. As the anode configuration according to the present invention, the configuration shown in FIGS. 1 and 2 is used, and the central part is 4
The anode was composed of a divided anode with one sheet at each side end.

The weight per unit area of the peeled copper foil was measured and the power of each anode was adjusted within the range of 0.1 to 1.0 A/dm''.

As a result, the variation in thickness in the width direction was reduced by the device of the present invention, and was able to be reduced from the conventional variation of about 3% to 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 has conventionally been done every time the anode is replaced, can be eliminated or significantly reduced, reducing various burdens associated with equipment maintenance.

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.

4. It is simpler than having the entire structure divided.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing the arrangement relationship between a cathode body and an anode in an embodiment of the present invention in which only the center portion of one sheet on the copper foil extraction side is constructed as a divided anode. 2 is a perspective view of the anode of FIG. 1; FIG. FIG. 3 is an explanatory diagram showing the arrangement relationship between a cathode body and an anode in conventional electrolytic copper foil production. 1: Cathode body 3: Anode 4: Split anode 5: Rectifier 7: Child rectifier Figure 1 Figure 2

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 for peeling electrodeposited copper foil from the cathode body, at least one of the anodes is divided into a plurality of foils having uniform thickness in the width direction, densely in the center and sparsely in the side edges. 1. An apparatus for producing electrolytic copper foil, comprising means for individually controlling the amount of electricity supplied to the divided anodes for uniformizing the thickness of the foil.