JPH04165100A - Method for regenerating copper-zinc-based alloy anode - Google Patents
Method for regenerating copper-zinc-based alloy anodeInfo
- Publication number
- JPH04165100A JPH04165100A JP29249590A JP29249590A JPH04165100A JP H04165100 A JPH04165100 A JP H04165100A JP 29249590 A JP29249590 A JP 29249590A JP 29249590 A JP29249590 A JP 29249590A JP H04165100 A JPH04165100 A JP H04165100A
- Authority
- JP
- Japan
- Prior art keywords
- anode
- copper
- zinc
- cyanide
- based alloy
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- TVZPLCNGKSPOJA-UHFFFAOYSA-N copper zinc Chemical compound [Cu].[Zn] TVZPLCNGKSPOJA-UHFFFAOYSA-N 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims description 14
- 230000001172 regenerating effect Effects 0.000 title claims description 5
- 229910045601 alloy Inorganic materials 0.000 title abstract description 6
- 239000000956 alloy Substances 0.000 title abstract description 6
- XFXPMWWXUTWYJX-UHFFFAOYSA-N Cyanide Chemical compound N#[C-] XFXPMWWXUTWYJX-UHFFFAOYSA-N 0.000 claims abstract description 20
- 229910000288 alkali metal carbonate Inorganic materials 0.000 claims abstract description 10
- 150000008041 alkali metal carbonates Chemical class 0.000 claims abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000005406 washing Methods 0.000 claims abstract description 5
- 229910001297 Zn alloy Inorganic materials 0.000 claims description 18
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 abstract description 28
- 238000007747 plating Methods 0.000 abstract description 20
- 229910000029 sodium carbonate Inorganic materials 0.000 abstract description 14
- MNWBNISUBARLIT-UHFFFAOYSA-N sodium cyanide Chemical compound [Na+].N#[C-] MNWBNISUBARLIT-UHFFFAOYSA-N 0.000 abstract description 9
- 238000009713 electroplating Methods 0.000 abstract description 7
- 150000004649 carbonic acid derivatives Chemical class 0.000 abstract description 5
- 239000007864 aqueous solution Substances 0.000 description 13
- 239000000243 solution Substances 0.000 description 10
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 5
- 238000011282 treatment Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 239000011701 zinc Substances 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 229910052725 zinc Inorganic materials 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- DOBRDRYODQBAMW-UHFFFAOYSA-N copper(i) cyanide Chemical compound [Cu+].N#[C-] DOBRDRYODQBAMW-UHFFFAOYSA-N 0.000 description 2
- 229910021645 metal ion Inorganic materials 0.000 description 2
- 238000004064 recycling Methods 0.000 description 2
- 230000008929 regeneration Effects 0.000 description 2
- 238000011069 regeneration method Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000011889 copper foil Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000005034 decoration Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000010907 mechanical stirring Methods 0.000 description 1
- 230000010534 mechanism of action Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000001376 precipitating effect Effects 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000007790 scraping Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- UTLZBWAGLRNNAY-UHFFFAOYSA-J thorium(4+);dicarbonate Chemical compound [Th+4].[O-]C([O-])=O.[O-]C([O-])=O UTLZBWAGLRNNAY-UHFFFAOYSA-J 0.000 description 1
- 238000002525 ultrasonication Methods 0.000 description 1
Landscapes
- Electroplating And Plating Baths Therefor (AREA)
- Electrolytic Production Of Metals (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、銅−亜鉛系合金の電気メツキにおいてアノー
ドとして用いる、銅−亜鉛系合金アノードの再生方法に
関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for regenerating a copper-zinc alloy anode used as an anode in electroplating of a copper-zinc alloy.
（従来の技術）
従来より、銅系合金の装飾のため、またニッケルメッキ
やコバルトメツキの下地調整用のために銅−亜鉛系合金
メツキが広く行われている。この銅−亜鉛系合金メツキ
は、アノードとして銅−亜鉛系合金を用い、メツキ浴と
してＣｕ ＣＮ ％ Ｚ ｎ（ＣＮ）ｔ 、ＮａＣＮ、
ＫＣＮなどからなる浴を用いる電気メツキ法である。(Prior Art) Copper-zinc alloy plating has been widely used for decoration of copper alloys and for preparing the base for nickel plating and cobalt plating. This copper-zinc alloy plating uses a copper-zinc alloy as an anode and a plating bath of CuCN%Zn(CN)t, NaCN,
This is an electroplating method that uses a bath made of KCN or the like.
このメツキ浴に用いるシアン化物（ＣＮ−）は、メツキ
洛中の金属イオンと錯体をつくって金属イオンの活量を
減少させ、析出合金の組成を安定させる効果がある。Cyanide (CN-) used in this plating bath has the effect of forming a complex with the metal ions in the plating bath, reducing the activity of the metal ions, and stabilizing the composition of the precipitated alloy.
（発明が解決しようとする課題）
メツキ浴に含まれるＮａＣＮ、ＫＣＮは、空気中の二酸
化炭素と反応し、それぞれＮ ａ ！ ＣＯｓ ％Ｋ
！ ＣＯｓに変化する。また、電気メツキ中のＣＮ−の
分解によっても同様の生成物が生じる。これらの炭酸塩
は、ある程度は浴中に溶解するため短期的には操業に影
響することはないが、長期的には過飽和となり、析出し
た炭酸塩がアノード表面に付着し、それを被覆してしま
うことがある。このようにアノード表面が炭酸塩で覆わ
れてしまうと、銅−亜鉛合金のイオン化が妨げられ、メ
ツキが困難となる。(Problems to be Solved by the Invention) NaCN and KCN contained in the plating bath react with carbon dioxide in the air, each producing Na! COs %K
! Changes to COs. Similar products also result from the decomposition of CN- during electroplating. These carbonates dissolve in the bath to some extent, so they do not affect operation in the short term, but in the long term they become supersaturated, and the precipitated carbonates adhere to the anode surface and coat it. Sometimes I put it away. When the anode surface is covered with carbonate in this way, ionization of the copper-zinc alloy is hindered, making plating difficult.
従来は、このような場合、メツキ浴中においてアノード
表面に付着した炭酸塩を機械的操作によって掻き取るこ
とにより、再生している。しかし、この作業は非常に煩
雑で、炭酸塩の完全な除去も困難である。また、掻き取
った炭酸塩が再度メツキ洛中に混入するという問題も生
じる。Conventionally, in such cases, carbonate adhering to the anode surface is scraped off by mechanical operation in a plating bath to regenerate the anode. However, this operation is very complicated and it is difficult to completely remove carbonates. In addition, there is also the problem that the scraped carbonate may be mixed into the mesh again.
本発明は、上記問題点を解決し、アノード表面を覆った
アルカリ金属の炭酸塩を、簡単に、かつ短時間で除去し
、アノードの再使用を可能にする、銅−亜鉛系合金アノ
ードの再生方法を提供することを目的とする。The present invention solves the above problems and allows the regeneration of copper-zinc alloy anodes by easily and quickly removing alkali metal carbonates covering the anode surface and making it possible to reuse the anode. The purpose is to provide a method.
（課題を解決するための手段及び作用）本発明の銅−亜
鉛系合金アノードの再生方法は、表面がアルカリ金属の
炭酸塩で覆われた銅−亜鉛系合金アノードを、シアン化
物水溶液により処理し、必要に応じて水洗する方法であ
る。(Means and effects for solving the problem) The method for regenerating a copper-zinc alloy anode of the present invention involves treating a copper-zinc alloy anode whose surface is covered with an alkali metal carbonate with an aqueous cyanide solution. This method involves rinsing with water if necessary.
銅−亜鉛系合金アノード（以下「アノード」という）を
シアン化物水溶液で処理する方法は、アノードとシアン
化物水溶液とを充分に接触させることができる方法であ
れば特に制限されるものではない。The method of treating a copper-zinc alloy anode (hereinafter referred to as "anode") with an aqueous cyanide solution is not particularly limited as long as the anode and the aqueous cyanide solution can be brought into sufficient contact.
この処理方法としては、例えば、シアン化物水溶液中に
、表面がアルカリ金属の炭酸塩で覆われたアノードを浸
漬する方法、シアン化物水溶液を循環させながら、その
流れの中に該アノードを浸漬する方法又はこれらと機械
的撹拌、超音波撹拌などの物理的手段若しくは加温操作
などを組み合わせた方法などを適用することができる。This treatment method includes, for example, immersing an anode whose surface is covered with an alkali metal carbonate in a cyanide aqueous solution, or immersing the anode in the flow of a cyanide aqueous solution while circulating it. Alternatively, a method combining these with physical means such as mechanical stirring or ultrasonic stirring, or heating operation can be applied.
ここで用いるシアン化物水溶液は特に制限されるもので
はないが、メツキ浴を構成するシアン化物の水溶液を用
いれば処理後の水洗が不要となるために好ましい。この
シアン化物水溶液中のシアン化物の濃度は、１重量％以
上であることが好ましい。The aqueous cyanide solution used here is not particularly limited, but it is preferable to use an aqueous cyanide solution constituting the plating bath because washing with water after treatment is not necessary. The concentration of cyanide in this aqueous cyanide solution is preferably 1% by weight or more.
シアン化物水溶液による処理後に行う水洗は、メツキ浴
を構成するシアン化物と異なるシアン化物の水溶液を用
いた場合にのみ行う。Washing with water after treatment with an aqueous cyanide solution is performed only when an aqueous solution of a cyanide different from the cyanide constituting the plating bath is used.
以上の操作により、アノード表面を覆ったアルカリ金属
の炭酸塩を容易に除去できるが、これは次のような作用
機構による。銅−亜鉛系合金の電気メツキを長期間継続
すると、メツキ浴に由来して生したアルカリ金属の炭酸
塩が過飽和状態となり、メツキ浴に溶解することかでき
ずに析出し、アノード表面に付着する。このため、前記
炭酸塩が溶解していないシアン化物水溶液とアノードを
接触させれば、アノード表面に付着している炭酸塩はシ
アン化物水溶液に溶解し、除去される。By the above operation, the alkali metal carbonate covering the anode surface can be easily removed, and this is due to the following mechanism of action. When electroplating of copper-zinc alloys is continued for a long period of time, the alkali metal carbonates produced in the plating bath become supersaturated and cannot be dissolved in the plating bath, precipitating and adhering to the anode surface. . Therefore, if the anode is brought into contact with an aqueous cyanide solution in which the carbonate is not dissolved, the carbonate adhering to the anode surface will be dissolved in the aqueous cyanide solution and removed.
（実施例）
実施例１
メツキ浴としてＣｕＣＮ （１００ｇ／ｊ２） 、Ｚｎ
（ＣＮ）！ （６ｇ＃） 、ＮａＣＮ （１１０ｇ／
ｊ’）及びＮａＯＨ（７０ｇ＃りを用い、メツキ条件を
浴温度７０℃、電流密度１２Ａ／ｄｍ”及びアノードＣ
ｕ−２０％Ｚｎとして１月操業後、表面に炭酸ナトリウ
ムが厚く付着したアノードを取り出した。(Example) Example 1 CuCN (100g/j2), Zn as plating bath
(CN)! (6g#), NaCN (110g/
j') and NaOH (70 g), the plating conditions were a bath temperature of 70°C, a current density of 12 A/dm, and an anode C.
After operation for January with u-20% Zn, the anode with a thick layer of sodium carbonate on its surface was taken out.
次に、前記アノードを５％−ＮａＣＮ水溶液の循環流中
に約６０分間浸漬した。その後、アノードを取り出した
ところ、表面を覆っていた炭酸ナトリウムは完全に除去
されていた。このアノードを用い銅−亜鉛系合金メツキ
を行ったところ、使用開始時と同様にメツキすることが
できた。The anode was then immersed in a circulating flow of 5% NaCN aqueous solution for about 60 minutes. When the anode was then taken out, the sodium carbonate that had covered its surface had been completely removed. When copper-zinc alloy plating was performed using this anode, plating could be performed in the same manner as at the beginning of use.
実施例２
実施例１で得た表面に炭酸ナトリウムが付着したアノー
ドを１５％−ＮａＣＮ水溶液の循環流中に約５０分浸漬
した。その後、アノードを取り出したところ、表面を覆
っていた炭酸ナトリウムは完全に除去されていた。Example 2 The anode obtained in Example 1, the surface of which was coated with sodium carbonate, was immersed in a circulating flow of a 15% NaCN aqueous solution for about 50 minutes. When the anode was then taken out, the sodium carbonate that had covered its surface had been completely removed.
実施例３
実施例１で得た表面に炭酸ナトリウムが付着したアノー
ドを２％−ＮａＣＮ水溶液中に浸漬し、かつ該水溶液を
機械的に撹拌した。約２０分経過後にアノードを取り出
したところ、表面を覆っていた炭酸ナトリウムは完全に
除去されていた。Example 3 The anode obtained in Example 1 with sodium carbonate attached to its surface was immersed in a 2% NaCN aqueous solution, and the aqueous solution was mechanically stirred. When the anode was taken out after about 20 minutes, the sodium carbonate covering the surface had been completely removed.
実施例４
実施例１で得た表面に炭酸ナトリウムが付着したアノー
ドを１０％−ＮａＣＮ水溶液中に浸漬し、かつ該水溶液
を機械的に撹拌した。約１８分経過後にアノードを取り
出したところ、表面を覆っていた炭酸ナトリウムは完全
に除去されていた。Example 4 The anode obtained in Example 1 with sodium carbonate attached to its surface was immersed in a 10% NaCN aqueous solution, and the aqueous solution was mechanically stirred. When the anode was taken out after about 18 minutes, the sodium carbonate covering the surface had been completely removed.
実施例５
実施例１で得た表面に炭酸ナトリウムが付着したアノー
ドを３％−ＮａＣＮ水溶液中に浸漬し、かつ該水溶液を
超音波により撹拌した。約３０分経過後にアノードを取
り畠したところ、表面を覆っていた炭酸ナトリウムは完
全に除去されていた。Example 5 The anode obtained in Example 1 with sodium carbonate attached to its surface was immersed in a 3%-NaCN aqueous solution, and the aqueous solution was stirred by ultrasonic waves. When the anode was removed after about 30 minutes, the sodium carbonate covering the surface had been completely removed.
実施例６
実施例１で得た表面に炭酸ナトリウムが付着したアノー
ドを１８％−ＮａＣＮ水溶液中に浸漬し、かつ該水溶液
を超音波により撹拌した。約２５分経過後にアノードを
取り出したところ、表面を覆っていた炭酸ナトリウムは
完全に除去されていた。Example 6 The anode obtained in Example 1 with sodium carbonate attached to its surface was immersed in an 18% NaCN aqueous solution, and the aqueous solution was stirred by ultrasonication. When the anode was taken out after about 25 minutes, the sodium carbonate covering the surface had been completely removed.
比較例１
実施例１で得た表面に炭酸ナトリウムが付着したアノー
ドを充分に水洗し、乾燥した。その後、機械的操作によ
りアノード表面に付着した析出物を掻き取った後、再び
水洗し、乾燥した。その結果、掻き取り前にアノード表
面に付着していた炭酸士トリウムの約７０〜８０重量％
量は剥かれ落ちていたが、残部はアノード表面に付着し
たままであった。また、この一連の処理に要した時間は
約６時間であった。Comparative Example 1 The anode obtained in Example 1 with sodium carbonate attached to its surface was thoroughly washed with water and dried. Thereafter, precipitates adhering to the anode surface were scraped off by mechanical operation, and then washed with water again and dried. As a result, approximately 70-80% by weight of the thorium carbonate that had adhered to the anode surface before scraping.
A small amount had peeled off, but the remainder remained attached to the anode surface. Further, the time required for this series of treatments was about 6 hours.
（発明の効果）
本発明の銅−亜鉛系合金アノードの再生方法は、表面が
アルカリ金属の炭酸塩で覆われた銅−亜鉛系合金アノー
ドを、シアン化物水溶液により処理し、必要に応じて水
洗するものである。(Effects of the Invention) The method for regenerating a copper-zinc alloy anode of the present invention involves treating a copper-zinc alloy anode whose surface is covered with an alkali metal carbonate with an aqueous cyanide solution, and washing with water if necessary. It is something to do.
このような本発明を適用すれば、短時間で、かつ簡単な
方法により、表面がアルカリ金属の炭酸塩で覆われたア
ノードの再生ができる。そして、このアノードは、銅−
亜鉛系合金の電気メツキ用のアノードとして再使用でき
る。このため、従来のような煩雑で不完全なアノードの
再生処理が不要となり、銅−亜鉛系合金の電気メツキに
おける運転コストを大幅に低減できる。By applying the present invention, an anode whose surface is covered with an alkali metal carbonate can be regenerated in a short time and by a simple method. And this anode is copper-
Can be reused as an anode for electroplating zinc-based alloys. Therefore, the complicated and incomplete regeneration treatment of the anode as in the conventional method is not required, and the operating cost in electroplating of copper-zinc alloys can be significantly reduced.
本発明の銅−亜鉛系合金アノードの再生方法は、例えば
電子部品用銅箔などの銅−亜鉛メツキに用いるアノード
の再生方法として好適である。The method for recycling a copper-zinc alloy anode of the present invention is suitable as a method for recycling anodes used for copper-zinc plating, such as copper foil for electronic parts.
Claims (1)
アノードを、シアン化物水溶液により処理し、必要に応
じて水洗することを特徴とする銅−亜鉛系合金アノード
の再生方法。A method for regenerating a copper-zinc alloy anode, which comprises treating a copper-zinc alloy anode whose surface is covered with an alkali metal carbonate with an aqueous cyanide solution and, if necessary, washing the anode with water.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29249590A JP2795533B2 (en) | 1990-10-30 | 1990-10-30 | Regeneration method of copper-zinc alloy anode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29249590A JP2795533B2 (en) | 1990-10-30 | 1990-10-30 | Regeneration method of copper-zinc alloy anode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04165100A true JPH04165100A (en) | 1992-06-10 |
| JP2795533B2 JP2795533B2 (en) | 1998-09-10 |
Family
ID=17782563
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29249590A Expired - Fee Related JP2795533B2 (en) | 1990-10-30 | 1990-10-30 | Regeneration method of copper-zinc alloy anode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2795533B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104120460A (en) * | 2014-07-02 | 2014-10-29 | 广州鸿葳科技股份有限公司 | Method for removing scaling of surface of titanium anode for electrolytic copper foil |
-
1990
- 1990-10-30 JP JP29249590A patent/JP2795533B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104120460A (en) * | 2014-07-02 | 2014-10-29 | 广州鸿葳科技股份有限公司 | Method for removing scaling of surface of titanium anode for electrolytic copper foil |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2795533B2 (en) | 1998-09-10 |
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| LAPS | Cancellation because of no payment of annual fees |