JPS6123790A - Method for plating ni or ni alloy surface - Google Patents

Abstract

PURPOSE:To form plating having high adhesion on the surface of a material whose surface is made of Ni by activating the surface of the material by AC electrolysis in an acidic aqueous soln. contg. a mineral acid as the principal component and by carrying out desired plating. CONSTITUTION:The surface of a material whose surface is made of Ni or an Ni alloy such as Ni-Sn is uniformly activated by carrying out AC electrolysis in an acidic aqueous soln. contg. a mineral acid as the principal component at about 0.5-20A/cm<2> average current density and ordinary temp. - about 50 deg.C for about 5-60sec. Sulfuric acid, hydrochloric acid, sulfamic acid or the like is used as the mineral acid, the concn. is regulated to about 2-25%, and water soluble salts, a surfactant, etc. may be added to the aqueous soln. The activated surface is plated with copper or the like to form an underlayer, and it is plated with a noble metal such as gold, silver or palladium.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、ニッケル寸たはニッケル合金（以下総称して
ニッケルという。）からなる表面にメッキする方法に関
するものであり、特にニッケル表面に密着性の良好なメ
ッキ層を施すだめの該表面の活性化方法に関するもので
ある。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of plating a surface made of nickel or a nickel alloy (hereinafter collectively referred to as nickel), and particularly relates to a method of plating a surface made of nickel or a nickel alloy (hereinafter collectively referred to as nickel). The present invention relates to a method for activating the surface in order to apply a plating layer with good properties.

本発明は、無光沢ニッケルまたはニッケル合金メッキ面
、光沢ニッケルまたはニッケル合金メッキ面、あるいは
その他ニッケル捷だはニッケル合金からなるあらゆる材
料、素材、表向に対して広く適用可能である。The present invention is widely applicable to matte nickel or nickel alloy plated surfaces, bright nickel or nickel alloy plated surfaces, or any other material, material, or surface made of nickel or nickel alloy.

〔従来の技術〕[Conventional technology]

一般にニッケル表面は、不動態化しやすく、例えばニッ
ケルメッキを施した表面に、さらにメッキを行う場合、
そのメッキ層は下地のニッケルメッキ層との密着性は、
あまり良くないことが多い。In general, nickel surfaces are easily passivated; for example, when further plating is applied to a nickel-plated surface,
The adhesion of the plating layer to the underlying nickel plating layer is
It's often not very good.

特にニッケルメッキ下地層上に部分的にメッキを施すた
め、レノスト塗料あるいはマスキングテープを用いてマ
スキングを行う場合のように、工程上の制約から；−ノ
ケルメノ午層を一旦乾燥させなければならない場合には
、ニッケルメッキ層表面には、直ちに強固な酸化膜を形
成してし１い、密着性は著しく低いものになってしまっ
ていた。こ゛のタメ、ニッケル表面へのメッキには、通
常活性化処理が必要であり、硫酸、塩酸などの鉱酸を主
体として含む酸性浴あるいは市販の酸性活性化剤水溶液
などへの浸漬処理が一般に行われている。Particularly due to process constraints, such as when masking is performed using Renost paint or masking tape to partially plate a nickel-plated base layer; In this case, a strong oxide film was immediately formed on the surface of the nickel plating layer, resulting in extremely poor adhesion. For this reason, plating on nickel surfaces usually requires activation treatment, and immersion treatment in an acidic bath containing mainly mineral acids such as sulfuric acid or hydrochloric acid, or a commercially available aqueous solution of an acidic activator is generally performed. It is being said.

しかし、乾燥したニッケル表面のような強固な酸イヒ膜
に対しては、これらの処理方法の効果は不十分な場合が
多く、寸た比較的長時間の処理が必要であることから、
長尺状態の連続メッキ等においては、作業性が著しく低
下するという問題もある。However, these treatment methods are often insufficiently effective for strong acid films such as those on dried nickel surfaces, and require relatively long treatment times.
In continuous plating of long lengths, there is also the problem that workability is significantly reduced.

また、−ツケル酸化膜の溶解を促進するため、前記酸性
浴中で被処理面を陽極として電解処理することも試みら
れているが、この場合もニッケル表面の溶解が不均一に
進行しやすく、ピットを生じたり、外観がムラになるな
どの問題や陽極処理条件によってはニッケル面が不動態
化されて、より不活性になるなどの問題がある。Furthermore, in order to promote the dissolution of the nickel oxide film, attempts have been made to electrolytically treat the surface to be treated in the acidic bath using the surface to be treated as an anode, but in this case as well, the dissolution of the nickel surface tends to proceed unevenly. There are problems such as formation of pits and uneven appearance, and problems such as the nickel surface becoming passivated and becoming more inactive depending on the anodizing conditions.

〔発明の目的〕[Purpose of the invention]

本発明は、前述したような従来技術の欠点を解消し、ニ
ッケル表面に密着性よくメッキを行うことのできる新規
な表面処理方法を提供することを目的とするものである
。SUMMARY OF THE INVENTION An object of the present invention is to provide a novel surface treatment method that eliminates the drawbacks of the prior art as described above and can plate a nickel surface with good adhesion.

〔発明の概要〕[Summary of the invention]

すなわち本発明は、少なくとも表面がニッケルからなる
材料の該表面にメッキする方法において、該表面を鉱酸
を主体として含む酸性水溶液中で交流電解処理したのち
、所望のメッキを施すことを特徴とするニッケルからな
る表面にメッキする方法でちる。That is, the present invention is a method for plating the surface of a material whose surface is at least made of nickel, which is characterized in that the surface is subjected to alternating current electrolytic treatment in an acidic aqueous solution containing mainly mineral acids, and then the desired plating is applied. Chilled by plating the surface made of nickel.

本発明におけるニッケルとしては、冒頭に記載した通り
、ニッケルまたはニッケル合金を含み、ニッケルとして
は、微少程度の不純物を含んでもよいものである。まだ
ニッケル合金としてはニッケルにたとえばＳｎ、Ｓｎと
ＯＯ＋　ｐ、　Ｂなどの金属元素を含めて合金にしたも
のである。ニッケル合金としては具体的にはＮｉ　　Ｓ
ｎ合金、Ｎ１−ａｎ−Ｃ。As described at the beginning, nickel in the present invention includes nickel or a nickel alloy, and nickel may contain a minute amount of impurity. Nickel alloys are still alloyed with nickel and metal elements such as Sn, Sn, OO+p, and B. Specifically, the nickel alloy is NiS
n alloy, N1-an-C.

合金、Ｎ１−Ｐ合金、Ｎｉ−１３合金などがある。本発
明の材料としては、その少なくとも表面がこれらニッケ
ルまたニッケル合金によって構成されているものである
。ニッケルまたはニッケル合金の成分は表面層のみの場
合でもよく、また全体がそのような成分で構成されてい
てもよい。alloy, N1-P alloy, Ni-13 alloy, etc. The material of the present invention is one in which at least the surface thereof is composed of nickel or a nickel alloy. The nickel or nickel alloy component may be contained only in the surface layer, or the entire surface layer may be composed of such a component.

まだ本発明において最も特徴とされるところは、メッキ
を施すニッケル表面を鉱酸を主体として含む酸性水溶液
中に浸漬しておいて交流電流を通じて電解処理すること
にある。ここで交流電解処理とは、周期的に極性の反転
する電源を用いて電解処理することであり、被処理面で
あるニッケル表面の極性が陰極側で還元活性化、陽極側
で溶解を交互に繰り返すことにより不動態化されること
なく短時間処理で表面の不活性皮膜を均一に除去し、活
性化することができる。The most distinctive feature of the present invention is that the nickel surface to be plated is immersed in an acidic aqueous solution containing mainly mineral acids and subjected to electrolytic treatment using alternating current. Here, AC electrolytic treatment is electrolytic treatment using a power source whose polarity is periodically reversed, and the polarity of the nickel surface, which is the surface to be treated, is alternately reduced and activated on the cathode side and dissolved on the anode side. By repeating the process, the inert film on the surface can be uniformly removed and activated in a short time without passivation.

本発明のために用いられる交流電源としては、商用電源
とトランスを組み合わせだ一般の交流電源（５０〜６０
Ｈｚ正弦波）の他、極性が周期的に反転するものであれ
ば矩形波（・ξルス波）、三角波、等いずれの波形のも
のでもよい。周波数も任意に設定できるが、低周波数の
場合、ニッケルが陽極時に不動態化する可能性があるだ
め、１ｏＩｌｚ以−Ｌにすることが望ましい。The AC power source used for the present invention is a general AC power source (50 to 60
In addition to the waveform (Hz sine wave), any waveform such as a rectangular wave (.xirus wave) or a triangular wave may be used as long as the polarity is periodically reversed. The frequency can also be set arbitrarily, but in the case of a low frequency, nickel may become passivated when used as an anode, so it is desirable to set it to 1 o Ilz or more -L.

一方、電解処理浴の主体である鉱酸としては、硫酸、塩
酸、硝酸、スルファミン酸、過塩素酸などニッケルを陽
極的に溶解できるものであればよく、これらを単独また
は混合して用いることができる。濃度は特に限定されな
いが、通常は２〜２５係（重量％または容量係）程度が
望ましい。また必要に応じて浴の電導塵を増すための水
溶性塩類、被処理面の濡れ性を増すだめの界面活性剤な
どを添加してもよい。On the other hand, the mineral acid that is the main component of the electrolytic treatment bath may be any mineral acid that can dissolve nickel anodically, such as sulfuric acid, hydrochloric acid, nitric acid, sulfamic acid, and perchloric acid, and these can be used alone or in combination. can. Although the concentration is not particularly limited, it is usually desirable to have a concentration of about 2 to 25 parts (by weight or volume). If necessary, water-soluble salts to increase the amount of conductive dust in the bath, surfactants to increase the wettability of the surface to be treated, etc. may be added.

電解処理条件（平均電流密度、時間、浴温等）は、被処
理面の不活性度や処理浴の組成により異なるが、通常は
０．５〜２０　Ａ　７ｃｍ２．５〜６０秒、常温〜５０
℃の範囲内で行う。Electrolytic treatment conditions (average current density, time, bath temperature, etc.) vary depending on the inertness of the surface to be treated and the composition of the treatment bath, but are usually 0.5 to 20 A, 7 cm for 2.5 to 60 seconds, room temperature to 50
Perform within the range of ℃.

以上のごとく交流電解処理した表面には、たとえば銅の
下地メッキを施し、その上に金、銀、パラジウムなどの
貴金属をメッキすることができ、たとえば半導体装置用
リードフレームを製造する場合などに本発明を適用する
ことができる。The surface treated with AC electrolysis as described above can be plated with a copper base plating, and then a precious metal such as gold, silver, or palladium can be plated on top of it. The invention can be applied.

〔実施例〕〔Example〕

厚さ０．５論の銅板にワット浴（硫酸ニッケル２４０ｇ
／）、塩化ニッケル４　ｓ　ｇ／ｉｓホウ酸４ｏｇ／ｚ
）を用いて厚さ３μのＮ１メッキを行ない、水洗、水切
りを行なった後、１５０℃の恒温槽で５分間加熱乾燥し
てＮ１メツキＣｕ板試料を作成した。Watt bath (240 g of nickel sulfate) on a copper plate with a thickness of 0.5 mm
/), nickel chloride 4 s g/is boric acid 4 og/z
) was used to perform N1 plating to a thickness of 3 μm, followed by washing and draining, followed by heating and drying in a constant temperature bath at 150° C. for 5 minutes to prepare a N1 plated Cu plate sample.

上記乾燥Ｎｉメノギを１５　Ｖｏｌ　％の塩酸浴中でカ
ーゼン電極を対極とし、室温、平均電流密度８Ａ／ｄｍ
２．１５秒間の条件で交流電解処理（５０１４Ｚ、正弦
波）を行ない、水洗後引続いてＡＩ？ストライクメッキ
（ＡｇＯＮ２ｇ／）、ＫＯＮ７０ｇ／ノ、室温、２Ａ／
＋Ｉｍ２．１０秒）Ａｇメッキ（ＡｇＣＮ　４０ｇ／）
、ＫＯＮ　１００ｇ／／／、Ｉ（２Ｃ０３２０ｇ／／！
、室温、２Ａ／ｄｍ２．５μ）を行なった。The above dried Ni agate was placed in a 15 Vol % hydrochloric acid bath with a Kazen electrode as a counter electrode, and the average current density was 8 A/d at room temperature.
AC electrolytic treatment (5014Z, sine wave) was performed for 2.15 seconds, and after washing with water, AI? Strike plating (AgON2g/), KON70g/no, room temperature, 2A/
+Im2.10 seconds) Ag plating (AgCN 40g/)
, KON 100g///, I (2C0320g//!
, room temperature, 2A/dm2.5μ).

Ａｇメッキの密着性を評価するため、上記の材料を４５
０℃の熱板上で５分間加熱を行ない、Ａｇメッキのフク
レの有無を観察しだ。In order to evaluate the adhesion of Ag plating, the above material was
The material was heated on a hot plate at 0° C. for 5 minutes, and the presence or absence of blistering of the Ag plating was observed.

比較のだめ、Ｎｉメッキの活性化処理を行なわない場合
、上記実施例と同一の活性化処理浴を用いて、３０秒間
浸漬処理した場合、Ｎｉ面を陽極として２　Ａ／ｄｍ２
．　１５秒間直流電解処理した場合のそれぞれについて
も同様にＡｇメッキを行ない、加熱によシ密着性を調べ
た。この結果、表１に示すように、実施例ではＡ、ｇメ
ッキのフクレ、外観異常は全く認められず、比較例のい
ずれの場合よりも良好であることがわかる。For comparison, when the activation treatment of Ni plating is not performed, and when the same activation treatment bath as in the above example is used and the immersion treatment is performed for 30 seconds, the Ni plating is used as the anode and 2 A/dm2.
．． Ag plating was performed in the same manner for each of the samples subjected to DC electrolysis treatment for 15 seconds, and the adhesion was examined by heating. As a result, as shown in Table 1, no blisters or abnormalities in appearance were observed in the A and G platings in the Examples, indicating that the results were better than in any of the Comparative Examples.

（密着性の評価）　Ｏ：フクレなし、△：フクレ若干あ
り、×：フクレ多数 〔発明の効果〕 以上説明したように、本発明によれば短時間の処理でニ
ッケルまたはニッケル合金から々る表面を均一かつ十分
に活性化させることができ、従って引き続いて行うメッ
キによって形成されるメッキ層の該層への密着性を著し
く向上させることが　　　：できるので、製品の信頼性
、さらにその製造の作業性も良好となり、本発明の工業
的価値は極めて太きい。(Evaluation of adhesion) O: No blisters, △: Slight blisters, ×: Many blisters [Effects of the Invention] As explained above, according to the present invention, the surface of nickel or nickel alloy can be removed in a short time. can be uniformly and sufficiently activated, and therefore the adhesion of the plating layer formed by subsequent plating to the layer can be significantly improved: this can improve the reliability of the product and the manufacturing process. The properties are also good, and the industrial value of the present invention is extremely large.

Claims (1)

【特許請求の範囲】[Claims] 少なくとも表面がニッケルまたはニッケル合金からなる
材料の該表面にメッキする方法において、該表面を鉱酸
を主体として含む酸性水溶液中で交流電解処理したのち
、所望のメッキを施すことを特徴とするニッケルまたは
ニッケル合金からなる表面にメッキする方法。A method of plating the surface of a material at least made of nickel or a nickel alloy, characterized in that the surface is subjected to alternating current electrolytic treatment in an acidic aqueous solution containing mainly mineral acids, and then the desired plating is applied. A method of plating surfaces made of nickel alloys.