JP2002038291A - Anode for manufacturing metallic foil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anode for manufacturing a metal foil, which improves a production efficiency and a product quality of the metal foil, because the anode can be partially or totally repaired or exchanged easily, when the electrode has partially deteriorated or has come to an end of the life, and because a high current can be applied by means of preventing a concentration of the current, since a current obstructed part due to an attaching jig of an electrode piece to an electrode base is not generated. SOLUTION: The anode for manufacturing metal foil comprises several pieces of electrode 6 consisting of rectangular, thin metal sheet with a same or shorter length as a width of the electrode base 5, which are arranged in parallel at an inner face of the electrode base with an arc-shaped cross section and releasably attached to the electrode base. An electro-conductive spacer 9 made from thin metal sheet is placed between the electrode base and each piece of electrode. An electro-conductive spacer and the electrode base are tightened with at least one stud bolt 7 which is integrated to the piece of electrode and a nut 8 threadedly engaged to the bolt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a cylindrical rotating cathode and an anode having an arcuate cross-section disposed outside the rotating cathode.
By applying a current between both electrodes, a metal is electrolytically deposited on the rotating cathode surface, and a metal foil manufacturing apparatus for manufacturing a metal foil by continuously peeling off the metal deposition layer from the cathode surface.
More specifically, the present invention relates to improvement of an anode which is a main component of the apparatus.

[0002]

2. Description of the Related Art In order to produce a copper foil used for a printed wiring board or the like by an electrodeposition method, copper is generally electrolytically deposited on the surface of a rotating cathode in a metal foil producing apparatus having the above-mentioned structure. Has been widely used, which is continuously peeled off from the cathode surface and wound up as a copper foil.

[0003] As the anode, which is a main component of the copper foil electrolytic manufacturing apparatus, those made of lead or a lead alloy have conventionally been used. Recently, various insoluble anodes having an electrode active coating layer made of a noble metal oxide on an electrode plate having an arc-shaped cross section have been proposed instead. ing.

[0004]

In recent years, as the density of printed circuit boards has increased, thinner and more uniform copper foils have been required. The use of the insoluble anode as described above has alleviated problems such as contamination of the electrolytic solution and deterioration of product quality.However, even when an insoluble anode is used, it is repaired due to local consumption of the electrode active coating layer. Is required. However, since the electrode plate is a unitary member having an arc-shaped cross section, it is necessary to replace the entire electrode plate in order to repair the consumable part, and there is a problem in work efficiency.

In order to solve this problem, Japanese Patent Laid-Open Publication No.
In Japanese Patent Application Publication No. 02498, an insoluble anode formed by arranging a plurality of insoluble electrode pieces made of a thin metal plate side by side in an arc direction on the inner surface of an electrode substrate having an arc-shaped cross section and removably fixed with a jig such as a screw. Proposed. With this anode, when repairing a consumable part, the electrode piece can be removed and easily reactivated, but the thickness of the electrode piece is very thin, 2 mm or less, so the exhausted electrode active coating layer The operation of peeling off becomes difficult. In addition, a large number of screws are required to maintain good conduction between the electrode base and the electrode pieces, which not only takes time and effort to attach and detach the electrode pieces, but also causes the occurrence of spots due to the fact that the screw parts are not energized. There is a problem.

Japanese Patent Application Laid-Open No. 6-346270 proposes an electrode in which a plurality of insoluble electrode short pieces made of a thin metal plate are arranged adjacent to each other on the inner surface of an electrode base having an arc-shaped cross section without any gap in the arc direction and width direction. In this configuration, a bolt integrated with the electrode short piece is passed through the through-hole of the electrode base and fastened with a nut to fix the electrode short piece to the electrode base. Limited. In addition, in order to prevent the deformation of the electrode short piece due to the tightening of the bolt and the nut, it has been proposed to insert an insulating rubber between the electrode short piece and the electrode base. Great nature.

[0007]

SUMMARY OF THE INVENTION The present invention has been devised in order to solve the above-mentioned problems of the prior art, and has an inner surface of an electrode substrate having an arc-shaped cross section and having a width equal to or less than the width of the substrate. In an anode in which a plurality of strip-shaped sheet metal pieces having the following lengths are arranged in parallel and removably fixed to the electrode base, a metal sheet formed between the electrode base and each electrode piece. A conductive spacer and an electrode base are fastened by at least one stud bolt integrated with the electrode piece and a nut screwed to the stud bolt, the conductive spacer and the electrode base being interposed. .

In the anode for producing a metal foil according to the present invention,
The electrode piece and / or the conductive spacer is provided with an electrode active material coating layer containing a platinum group metal or a platinum group metal oxide.

The thickness of the conductive spacer is 0.2 to 6 m.
m, preferably 0.3 to 3 mm, more preferably 0.5 to 2 mm.

[0010] The material of the conductive spacer may be platinum, titanium, tantalum, niobium, zirconium or an alloy mainly composed of any of these.

The electrode active material preferably comprises a mixture of iridium oxide and tantalum oxide containing 60 to 95% by weight of iridium and 40 to 5% by weight of tantalum in terms of metal.

The electrode pieces and / or the conductive spacers
After forming a tantalum or tantalum alloy layer having a thickness of 0.5 to 15 μm on the surface, an electrode active material coating layer may be further formed thereon. The tantalum metal used here is amorphous, crystalline (α-tantalum,
β-tantalum).

The electrode piece may be curved in accordance with the curvature of the electrode base. Further, the electrode piece may be further divided into a plurality of pieces.

The material of the electrode piece and the electrode base is preferably a titanium-based alloy such as titanium metal, titanium-tantalum, titanium-tantalum-niobium, and titanium-palladium, and forms an electrode active layer covering the electrode piece. The substance may be iridium oxide or titanium, tantalum,
A mixed oxide with a valve metal such as niobium, tungsten or zirconium is preferred. Representative examples include iridium-tantalum mixed oxide, iridium-titanium mixed oxide, and the like. At this time, iridium is converted to 6
0 to 95% by weight, containing 40 to 5% by weight of tantalum;
A mixed oxide of iridium oxide and tantalum oxide has excellent durability. After forming a tantalum or tantalum alloy layer having a thickness of 0.5 to 15 microns on the electrode piece, and further forming an electrode active material coating layer thereon, the durability as an anode is further improved.

The anode according to the present invention is suitably used for producing a metal foil of copper, nickel or the like.

[0016]

In the anode for producing a metal foil according to the present invention, a plurality of strip-shaped metal sheet electrodes each having a length equal to or less than the width of the electrode base are provided on the inner surface of the electrode base having an arc-shaped cross section. Are arranged side by side in the arc direction and are detachably fixed to the electrode base, so that if the electrode is locally deteriorated or the electrode has reached the end of its service life, the anode can be easily repaired partially or entirely. Or can be replaced. Further, if the strip-shaped electrode piece is divided into a plurality of pieces, the divided pieces of the electrode piece can be exchanged according to the degree of deterioration of the central portion and the end portion of the electrode piece.

In the anode for producing a metal foil according to the present invention, in order to attach the electrode piece to the electrode base, at least the metal sheet conductive spacer is interposed between the electrode base and each electrode piece to be integrated with the electrode base. Since the conductive spacer and the electrode base are fastened with one stud bolt and a nut screwed to the stud bolt, no current-carrying portion due to a jig for mounting the electrode piece to the electrode base is not generated, and the current-carrying area is increased, and thus the current is increased. Concentration can be prevented and a large amount of current can flow.

Further, since the conductive spacer is made of a thin metal plate, there is no risk of burning of the power supply portion.

Further, by using a conductive spacer according to the amount of current, uniform and stable current can be secured. When the electrode active coating layers are provided on both surfaces of the conductive spacer, the electric conductivity of the surface is maintained for a long time.

As a result, a metal foil product can be obtained more efficiently, and the quality of the metal foil product can be improved.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the following examples.

Example 1 In FIGS. 1 and 2, a metal foil producing apparatus (1) is a cylindrical rotating cathode having a diameter of about 2000 mm and a width of 1500 mm.
(2), an anode (3) having a semicircular cross section arranged opposite to the outside thereof, an electrolytic cell (10) for accommodating them, and a winder (11) for winding the obtained metal foil. ) As the main components.

The anode (3) is immersed in the electrolytic solution in the electrolytic cell (10), is divided into two parts at the center of the arc, and a slit (4) for flowing the electrolytic solution is formed in the divided part. I have. Each divided portion of the anode (3) is made of a strip-shaped thin metal plate having a length equal to the width of the base (5) on the inner surface of a 25 mm-thick titanium electrode base (5) having a quarter-arc cross section. (1500 mm long, 100 mm wide, 3 mm thick) are arranged side by side in the width direction of the base and in the arc direction of the base. Electrode base (5) with multiple electrode pieces (6)
Is entirely covered. Each electrode piece (6) has a stud bolt (7) made of conductive metal or titanium integrated by welding on its outer surface, that is, a surface facing the electrode substrate (5), and a nut (8) screwed to the stud bolt. Thus, it is detachably fixed to the electrode base (5). Electrode surface of electrode piece (6)
The distance from the surface of (2) is 10 mm. Stud
In (7), nine electrodes are provided at 150 mm intervals in the length direction for each electrode piece.

The plurality of electrode pieces (6) are electrodes using iridium oxide as an active substance, which is produced by repeating the following coating operation of an electrode active substance five times. First, a titanium plate as a material is degreased by ultrasonic cleaning, and then blasted at a pressure of 4 kgf / cm ² for about 10 minutes using an # 30 alundum, and the treated material plate is washed in running water for 24 hours. And dried. An electrode active material coating solution having the following liquid composition was applied to the surface (surface) of the pretreated titanium plate thus obtained, which was used as an electrode, and dried at 100 ° C. for 10 minutes. At 500 ° C. for 20 minutes (the weight composition ratio of the electrode active material coating layer is Ir / Ta = 7).
/ 3).

The material liquid TaCl electrode active material _{5 0.32g H 2 IrCl 6 · 6H} 2 O 1.00g 35% HCl 1.0ml n-CH 3 (CH 2) 3 OH 10.0ml

A portion of the surface (back surface) not used as an electrode, which is in contact with the conductive spacer, was plated with platinum.

A conductive spacer (9) made of a thin metal plate is interposed between the electrode substrate (5) and each of the electrode pieces (6). The conductive spacer (9) has a diameter of 2 mm with a hole of 10 mm in the center.
It is a disk having a thickness of 5 mm and a thickness of 1 mm, and a bolt (7) is inserted through a central hole.

Both surfaces of the conductive spacer (9) were plated with platinum.

In the metal foil manufacturing apparatus (1) having the above structure,
As the electrolyte, sulfuric acid: 100 g / L, copper sulfate: 250 g
/ L, an aqueous solution containing glue as an additive was prepared and supplied to the electrolytic cell (10) so that the flow rate at the cathode surface was 2 m / s, and 80 A was applied between the electrodes (2) and (3). / Dm ² , the cathode (2) is rotated, copper is electrolytically deposited on the surface of the cathode (2), and the deposited copper layer having a thickness of 35 μm is continuously peeled off from the cathode surface. Copper foil was manufactured. The obtained metal foil was wound around a winder (11).

After 100 hours of continuous electrolysis, the thickness of the copper foil was measured at 1 cm intervals in the width direction using a film thickness gauge. Table 1 shows the results of measuring the thickness of the copper foil.

Example 2 After pretreating a titanium plate as a material by the same operation as in Example 1, the obtained pretreated titanium plate was put into a sputtering apparatus, placed at a position 20 mm from a target, and tantalum sputtering was performed. went. As a result of measuring the X-ray diffraction of the obtained coating film, a diffraction pattern of α-tantalum was recognized. The surface of the tantalum intermediate layer thus formed by sputtering is coated with an electrode active material by the same operation as in Example 1 to form an electrode piece, and the electrode piece is formed using the same conductive spacer as in Example 1. An anode was prepared by attaching to a substrate. This anode was subjected to an electrolytic copper foil production test in the same manner as in Example 1. The results of measuring the thickness of the copper foil are shown in Table 1.

COMPARATIVE EXAMPLE 1 An anode was formed in the same manner as in Example 1, except that a conductive spacer (9) made of a thin metal plate was not interposed between the electrode substrate (5) and each electrode piece (6). Produced. This anode was subjected to an electrolytic copper foil production test in the same manner as in Example 1. The results of measuring the thickness of the copper foil are shown in Table 1.

[0033]

[Table 1]

If the variation in the thickness of the copper foil is within 1%, it is regarded as "good", and if it exceeds 1% and within 2%, it is regarded as "acceptable".
Those exceeding 2% were regarded as "impossible".

As is clear from Table 1, in each of the embodiments in which the conductive spacer was interposed between the electrode base and the electrode piece, the current flow from the electrode base to the electrode piece was larger than in Comparative Example 1 having no spacer. Was good and uniform, the life was long due to stable consumption of the electrode active material, and a much better foil was obtained with a uniform thickness of the foil.

In Comparative Example 1, it is considered that the variation in foil thickness is increased because the life of the electrode active material in the portion where the current is concentrated is shortened.

[0037]

According to the anode for manufacturing a metal foil according to the present invention, when the electrode is locally deteriorated or when the electrode reaches the end of its life,
The anode can be repaired or replaced easily or partially or completely, and no current-carrying part due to the jig for attaching the electrode piece to the electrode base does not occur. Therefore, current concentration is prevented and a large amount of current flows. be able to. As a result, a metal foil product can be obtained more efficiently, and the quality of the metal foil product can be improved.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing an example of a metal foil manufacturing apparatus.

FIG. 2 is a vertical sectional view showing an example of an anode.

FIG. 3 is a perspective view showing an example of an anode.

[Explanation of symbols]

 1: Metal foil production apparatus 2: Cylindrical rotating cathode 3: Anode 5: Electrode base 6: Electrode piece 7: Stud bolt 8: Nut 9: Conductive spacer 10: Electrolytic tank

Claims (6)

[Claims] 1. An electrode comprising a plurality of strip-shaped thin metal plates having a length equal to or less than the width of an electrode substrate arranged in parallel on an inner surface of an electrode substrate having an arc-shaped cross section. In the anode detachably fixed to the base, a conductive spacer made of a thin metal plate is interposed between the electrode base and each electrode piece, and screwed to at least one stud bolt integrated with the electrode piece. An anode for producing a metal foil, wherein a conductive spacer and an electrode substrate are fastened with a nut. 2. The anode according to claim 1, wherein the electrode pieces and / or the conductive spacers are coated with an electrode active material coating layer containing a platinum group metal or a platinum group metal oxide. 3. The conductive spacer has a thickness of 0.2 to 6 m.
The anode for producing a metal foil according to claim 1 or 2, wherein m is m. 4. An electrode active material comprising a mixture of iridium oxide and tantalum oxide containing 60 to 95% by weight of iridium and 40 to 5% by weight of tantalum in terms of metal.
The anode for producing a metal foil according to claim 2. 5. An electrode piece and / or a conductive spacer formed by forming a tantalum or tantalum alloy layer having a thickness of 0.5 to 15 μm on a surface, and further forming an electrode active material coating layer thereon. The anode for producing a metal foil according to claim 2. 6. The electrode piece is further divided into a plurality of pieces.
The anode for producing a metal foil according to claim 1.