JPH0732307B2 - Surface treatment method for copper foil for printed circuits - Google Patents
Surface treatment method for copper foil for printed circuitsInfo
- Publication number
- JPH0732307B2 JPH0732307B2 JP35292291A JP35292291A JPH0732307B2 JP H0732307 B2 JPH0732307 B2 JP H0732307B2 JP 35292291 A JP35292291 A JP 35292291A JP 35292291 A JP35292291 A JP 35292291A JP H0732307 B2 JPH0732307 B2 JP H0732307B2
- Authority
- JP
- Japan
- Prior art keywords
- copper foil
- treatment
- zinc
- printed circuit
- plating
- 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.)
- Expired - Lifetime
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/38—Improvement of the adhesion between the insulating substrate and the metal
- H05K3/382—Improvement of the adhesion between the insulating substrate and the metal by special treatment of the metal
Landscapes
- Electroplating And Plating Baths Therefor (AREA)
- Electroplating Methods And Accessories (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
- Manufacturing Of Printed Wiring (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、印刷回路用銅箔の表面
処理方法に関するものであり、特には耐熱酸化性（プリ
ント基板等の製造時に適用される熱履歴に対して変色を
起こさないこと）を改善するために、Ｃｒ系防錆層形成
前にＺｎ−Ｃｏ合金層を形成することを特徴とする印刷
回路用銅箔の光沢面の処理方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment method for a copper foil for a printed circuit, and more particularly to a thermal oxidation resistance (not discoloration due to a heat history applied when manufacturing a printed circuit board or the like). The present invention relates to a method for treating a glossy surface of a copper foil for a printed circuit, which comprises forming a Zn-Co alloy layer before forming a Cr-based rust preventive layer in order to improve
【０００２】[0002]
【従来の技術】印刷回路用銅箔は一般に、合成樹脂等の
基材に高温高圧下で積層接着され、その後目的とする回
路を形成するべく必要な回路を印刷した後、不要部を除
去するエッチング処理が施される。最終的に、所要の素
子が半田付けされて、エレクトロニクスデバイス用の種
々の印刷回路板を形成する。印刷配線板用銅箔に対する
品質要求は、樹脂基材と接着される面（粗化面）と、非
接着面（光沢面）とで異なる。2. Description of the Related Art Generally, a printed circuit copper foil is laminated and adhered to a base material such as a synthetic resin under high temperature and high pressure, and after printing a necessary circuit to form a target circuit, unnecessary parts are removed. An etching process is performed. Finally, the required elements are soldered to form various printed circuit boards for electronic devices. Quality requirements for a copper foil for a printed wiring board differ between a surface (roughened surface) bonded to a resin substrate and a non-bonded surface (glossy surface).
【０００３】粗化面に対する要求としては、主として、
保存時における酸化変色のないこと、基材との引き
剥し強さが高温加熱、湿式処理、半田付け、薬品処理等
の後でも充分なこと、基材との積層、エッチング後に
生じる所謂積層汚点のないこと等が挙げられる。The requirements for the roughened surface are mainly
No oxidative discoloration during storage, sufficient peeling strength from the base material even after high temperature heating, wet treatment, soldering, chemical treatment, etc. There is no such thing.
【０００４】他方、光沢面に対しては、 外観が良好なこと及び保存時における酸化変色のない
こと、 半田濡れ性が良好なこと、 高温加熱時に酸化変色がないこと レジストとの密着性が良好なこと 等が要求される。On the other hand, the glossy surface has a good appearance, no oxidative discoloration during storage, good solder wettability, no oxidative discoloration when heated at high temperature, and good adhesion to the resist. Something is required.
【０００５】こうした要求に応えるべく、粗化面及び光
沢面について印刷配線板用銅箔に対して様々の目的で多
くの処理方法が提唱されてきた。特に銅箔の防錆処理に
注目すると、有用な基本的防錆方法の一つとして、本件
出願人は、特公昭６１−３３９０８号において銅箔の光
沢面に亜鉛の皮膜を形成し、続いてクロム酸化物の皮膜
によるクロム防錆層を形成する方法を提唱した。また、
クロム防錆層自体に関しても、電解亜鉛・クロム処理に
よるクロム酸化物と亜鉛及び（又は）亜鉛酸化物との混
合皮膜処理を提唱し（特公昭５８−７０７７号）、多く
の成果を挙げてきた。更に、特開平２−２９４４９０号
には、長期間高温多湿条件下での黒点発生を防止するこ
とを目的として、浸漬クロメート処理によりクロム酸化
物皮膜を形成し、続いて電解亜鉛・クロム処理によりク
ロム酸化物と亜鉛及び（又は）亜鉛酸化物との混合皮膜
を形成することが開示される。In order to meet such demands, many treatment methods have been proposed for various purposes for the roughened surface and the glossy surface of the copper foil for printed wiring board. In particular, paying attention to the anticorrosion treatment of the copper foil, the applicant of the present invention, as one of the useful basic antirust methods, formed a zinc film on the glossy surface of the copper foil in Japanese Patent Publication No. 61-33908, and subsequently, A method of forming a chromium anticorrosion layer by a chromium oxide film was proposed. Also,
Regarding the chrome rust preventive layer itself, a mixed film treatment of chromium oxide and zinc and / or zinc oxide by electrolytic zinc / chromium treatment has been proposed (Japanese Patent Publication No. 58-7077) and many results have been achieved. . Further, in Japanese Patent Laid-Open No. 2-294490, for the purpose of preventing the generation of black spots under high temperature and high humidity conditions for a long period of time, a chromium oxide film is formed by immersion chromate treatment, and then chromium is treated by electrolytic zinc / chromium treatment. It is disclosed to form a mixed film of oxide and zinc and / or zinc oxide.
【０００６】[0006]
【発明が解決しようとする課題】ところで、銅箔の光沢
面の耐熱酸化性に関しては、年々要求が厳しくなってい
る。一つには、従来なかった新しい製作方式（２層フレ
キ：ポリイミドワニスを直接銅箔上へ塗布し、フレキシ
ブル基板とする方法で、ポリイミド層と銅箔層の２層構
造となっているため、２層フレキと呼ばれている。）及
び高耐熱性の新規樹脂の出現に伴い、銅箔が今までより
も高い温度に曝露されるようになったためである。ま
た、従来の積層方法においても、加熱処理を行う積層及
びキュアー工程のコスト削減のために今までの窒素雰囲
気から大気中で行なう傾向も見られ、この点からも銅箔
光沢面の耐熱酸化性の改善が要求されるようになった。
現在の亜鉛めっき＋クロメート処理の方法では、例えば
２００℃×３０分程度しか耐熱酸化性が保持されず、今
後必要とされる２４０℃×３０分或いは２７０℃×１０
分の高温条件では変色してしまう。従って、今後の印刷
回路用銅箔ヘの要求に対応するためには、２４０℃×３
０分或いは２７０℃×１０分といったもっと高温の条件
でも変色しない一層高度の耐熱酸化性を確保することが
必要である。しかも、半田濡れ性、レジスト密着性とい
った光沢面に要求される他の特性を損なうものであって
はならないことはもちろんである。By the way, with respect to the thermal oxidation resistance of the glossy surface of the copper foil, the requirements are becoming stricter year by year. One is a new manufacturing method that has never existed before (two-layer flex: a polyimide varnish is directly applied on a copper foil to form a flexible substrate, which has a two-layer structure of a polyimide layer and a copper foil layer. This is because the copper foil is exposed to higher temperatures than before with the advent of new resins with high heat resistance. In addition, even in the conventional laminating method, there is a tendency to perform the heat treatment in the atmosphere from the nitrogen atmosphere in order to reduce the cost of the laminating and curing processes. Improvement has come to be demanded.
With the current method of zinc plating + chromate treatment, the thermal oxidation resistance is maintained only for, for example, about 200 ° C. × 30 minutes, and 240 ° C. × 30 minutes or 270 ° C. × 10 which will be required in the future.
It discolors under high temperature conditions for a minute. Therefore, in order to meet the future demand for copper foil for printed circuits, 240 ° C x 3
It is necessary to secure higher thermal oxidation resistance that does not discolor even under higher temperature conditions such as 0 minutes or 270 ° C. × 10 minutes. In addition, it must not impair other properties required for the glossy surface such as solder wettability and resist adhesion.
【０００７】本発明の課題は、従来からの亜鉛めっき＋
クロメート処理方法において、今後のプリント基板製造
時に予想される熱履歴に対しても変色を起こさないよう
銅箔光沢面の耐熱酸化性を高め、しかも半田濡れ性、レ
ジスト密着性といった他の特性を損なうことのない処理
方法を開発することである。The object of the present invention is to provide conventional zinc plating +
In the chromate treatment method, the thermal oxidation resistance of the glossy surface of the copper foil is increased so as not to cause discoloration with respect to the thermal history expected in the future production of printed circuit boards, and other properties such as solder wettability and resist adhesion are impaired. It is to develop a unique processing method.
【０００８】[0008]
【課題を解決するための手段】本発明者等は、従来の亜
鉛単独めっきに替えてごく薄いＺｎ−Ｃｏ合金皮膜を形
成することにより上記光沢面の耐熱酸化性に対する課題
を解決しうることを見出した。Ｚｎ−Ｃｏ合金めっきの
銅箔への応用として、銅箔の光沢面ではなく、粗化面に
対して主として剥離強度を向上することを課題としてＺ
ｎ−Ｃｏ合金めっき行なう試みは存在するが（例えば、
特開昭６３−８９６９８号、特公平２−５１２７２号
等）、光沢面と粗化面とでは前述したように要求される
要件が全く異なり、特に上記の公知の方法では、めっき
厚みがあまりにも厚く、プリント基板用銅箔としては外
観上問題があり、とても使用できるレベルではない。そ
こで上記の方法で約３μｍ程度のめっきのものをプリン
ト基板用として、数十から数百Å厚さの領域へ応用でき
るよう鋭意研究を行った。その結果、非常に薄いＺｎ−
Ｃｏ合金被膜を光沢面に施すことにより、意外にも光沢
面の耐熱酸化性が改善されることを初めて見いだしたも
のである。Means for Solving the Problems The present inventors have found that the problem with respect to the thermal oxidation resistance of the glossy surface can be solved by forming a very thin Zn--Co alloy film in place of the conventional zinc single plating. I found it. As an application of the Zn-Co alloy plating to a copper foil, the main object is to improve the peeling strength on the roughened surface of the copper foil, not on the glossy surface.
Although there are attempts to perform n-Co alloy plating (for example,
(Japanese Patent Laid-Open No. 63-89698, Japanese Patent Publication No. 2-51272, etc.), the requirements required as described above are completely different between the glossy surface and the roughened surface. Particularly, in the above known method, the plating thickness is too large. Since it is thick and has a problem in appearance as a copper foil for printed circuit boards, it is not at a level at which it can be used. Therefore, the above-mentioned method has been eagerly studied so as to apply the plating of about 3 μm for a printed circuit board and to apply it to a region of several tens to several hundreds of Å thickness. As a result, very thin Zn-
It was discovered for the first time that the thermal oxidation resistance of the glossy surface was unexpectedly improved by applying the Co alloy coating to the glossy surface.
【０００９】この知見に基づいて、本発明は、印刷回路
用銅箔の光沢面に５０〜９７重量％Ｚｎと３〜５０重量
％Ｃｏとから成るＺｎ−Ｃｏ合金層を１００〜５００μ
ｇ／ｄｍ2 の付着量で形成し、その後該Ｚｎ−Ｃｏ合金
層上にＣｒ系防錆層を形成することを特徴とする印刷回
路用銅箔の表面処理方法を提供するものである。この場
合、前記銅箔の粗化面（非光沢面）にはＣｕ、Ｃｒ、Ｎ
ｉ、Ｆｅ、Ｃｏ及びＺｎから選択される１種乃至２種以
上の単一金属層又は合金層を形成するトリート処理を行
なうことが好ましい。耐候性を一層良好にするには、Ｃ
ｒ系防錆層を浸漬クロメート乃至電解クロメート処理に
よるクロム酸化物皮膜及び（或いは）電解亜鉛・クロム
処理によるクロム酸化物と亜鉛及び（又は）亜鉛酸化物
との混合皮膜から形成するのがよい。Based on this knowledge, the present invention provides a Zn-Co alloy layer of 50 to 97% by weight Zn and 3 to 50% by weight Co on a glossy surface of a copper foil for a printed circuit in an amount of 100 to 500 μm.
The present invention provides a surface treatment method for a copper foil for a printed circuit, which is characterized in that it is formed with an adhesion amount of g / dm 2 and then a Cr-based anticorrosion layer is formed on the Zn—Co alloy layer. In this case, on the roughened surface (non-glossy surface) of the copper foil, Cu, Cr, N
It is preferable to perform a treat treatment for forming a single metal layer or an alloy layer of one or more selected from i, Fe, Co and Zn. To further improve weather resistance, C
It is preferable that the r-based rust preventive layer is formed of a chromium oxide film by immersion chromate or electrolytic chromate treatment and / or a mixed film of chromium oxide and zinc and / or zinc oxide by electrolytic zinc / chromium treatment.
【００１０】[0010]
【作用】印刷回路用銅箔の光沢面にＺｎ−Ｃｏ合金皮膜
を形成する。Ｚｎ−Ｃｏ合金処理は、好ましくはＺｎ−
Ｃｏ電解めっき浴を使用して、５０〜９７重量％Ｚｎ及
び３〜５０重量％Ｃｏの組成のＺｎ−Ｃｏ合金層を１０
０〜５００μｇ／ｄｍ2の付着量でごく薄く形成するよ
うに実施される。Ｃｏ量が３重量％未満では耐熱酸化性
の所要の向上が得られない。他方Ｃｏ量が５０重量％を
超えると、半田濡れ性が悪化すると共に、耐熱酸化性も
また悪化する。Ｚｎ−Ｃｏ合金層の付着量が１００μｇ
／ｄｍ2 未満では、耐熱酸化性の向上が得られない。他
方５００μｇ／ｄｍ2 を超えると、Ｚｎ等の拡散により
導電性が悪化する。Ｚｎ−Ｃｏ合金層は銅箔光沢面の耐
熱酸化性を高め、しかも半田濡れ性、レジスト密着性と
いった他の特性を損なうことはない。Function: A Zn-Co alloy film is formed on the glossy surface of the printed circuit copper foil. The Zn-Co alloy treatment is preferably Zn-
A Zn-Co alloy layer having a composition of 50 to 97% by weight Zn and 3 to 50% by weight Co was formed by using a Co electrolytic plating bath.
It is carried out so as to form a very thin film with an adhesion amount of 0 to 500 μg / dm 2 . If the amount of Co is less than 3% by weight, the required improvement in thermal oxidation resistance cannot be obtained. On the other hand, when the amount of Co exceeds 50% by weight, the solder wettability deteriorates and the thermal oxidation resistance also deteriorates. The amount of Zn-Co alloy layer deposited is 100 μg
If it is less than / dm 2 , the improvement in thermal oxidation resistance cannot be obtained. On the other hand, when it exceeds 500 μg / dm 2 , conductivity is deteriorated due to diffusion of Zn and the like. The Zn-Co alloy layer enhances the thermal oxidation resistance of the glossy surface of the copper foil and does not impair other properties such as solder wettability and resist adhesion.
【００１１】[0011]
【実施例】本発明において使用する銅箔は、電解銅箔或
いは圧延銅箔いずれでもよい。本発明自体は銅箔の光沢
面と関与するが、参考までに銅箔粗化面についても述べ
ておく。通常、銅箔の、樹脂基材と接着する面即ち粗化
面には積層後の銅箔の引き剥し強さを向上させることを
目的として、脱脂後の銅箔の表面に例えば銅のふしこぶ
状の電着を行なう銅粗化処理が施される。こうした銅の
ふしこぶ状の電着はいわゆるヤケ電着により容易にもた
らされる。粗化前の前処理として通常の銅めっき等がそ
して粗化後の仕上げ処理として通常の銅めっき等が行な
われることもある。EXAMPLES The copper foil used in the present invention may be either electrolytic copper foil or rolled copper foil. Although the present invention is concerned with the glossy surface of the copper foil, the roughened surface of the copper foil will be described for reference. Usually, on the surface of the copper foil that is bonded to the resin substrate, that is, the roughened surface, for the purpose of improving the peeling strength of the copper foil after lamination, the surface of the copper foil after degreasing, for example, is made of copper Roughening treatment is performed to perform electrodeposition in the shape of copper. Such copper kinky electrodeposition is easily brought about by so-called burn electrodeposition. Normal copper plating or the like may be performed as a pretreatment before roughening, and normal copper plating or the like may be performed as a finishing treatment after roughening.
【００１２】銅粗化処理の例としては、例えば次の条件
が採用され得る。 銅粗化処理 Cu ： １０〜２５g/l H2SO4 ： ２０〜１００g/l 温度 ： ２０〜４０℃ Ｄk ： ３０〜７０A/dm2 時間 ： １〜５秒As an example of the copper roughening treatment, for example, the following conditions can be adopted. Copper roughening treatment Cu: 10 to 25 g / l H 2 SO 4 : 20 to 100 g / l Temperature: 20 to 40 ° C. D k : 30 to 70 A / dm 2 hours: 1 to 5 seconds
【００１３】粗化処理後に、該粗化面にＣｕ、Ｃｒ、Ｎ
ｉ、Ｆｅ、Ｃｏ及びＺｎから選択される１種乃至２種以
上の単一金属層又は合金層を形成するトリート処理を行
なうことが好ましい。合金めっきの例としては、Ｃｕ−
Ｎｉ、Ｃｕ−Ｃｏ、Ｃｕ−Ｎｉ−Ｃｏ、Ｃｕ−Ｚｎその
他を挙げることが出来る（詳細は、特公昭５６−９０２
８号、特開昭５４−１３９７１号、特開平２−２９２８
９５号、特開平２−２９２８９４号、特公昭５１−３５
７１１号、特公昭５４−６７０１号等を参照のこと）。
こうしたトリート処理は、銅箔の最終性状を決定するも
のとしてまた障壁としての役割を果たす。After the roughening treatment, Cu, Cr, N is formed on the roughened surface.
It is preferable to perform a treat treatment for forming a single metal layer or an alloy layer of one or more selected from i, Fe, Co and Zn. As an example of alloy plating, Cu-
Ni, Cu-Co, Cu-Ni-Co, Cu-Zn and others can be mentioned (for details, see JP-B-56-902).
No. 8, JP-A-54-13971, JP-A-2-2928.
No. 95, JP-A-2-292894, Japanese Patent Publication No. 51-35.
711, Japanese Examined Patent Publication No. 54-6701, etc.).
Such treat treatment serves as a determinant and barrier to the final properties of the copper foil.
【００１４】本発明に従えば、銅箔の粗化面にトリート
処理を伴って或いは伴わずして、光沢面にＺｎ−Ｃｏ合
金処理が実施される。Ｚｎ−Ｃｏ合金処理は、好ましく
はＺｎ−Ｃｏ電解めっき浴を使用して５０〜９７重量％
Ｚｎ及び３〜５０重量％Ｃｏを含むＺｎ−Ｃｏ合金層を
１００〜５００μｇ／ｄｍ2 の付着量でごく薄く形成す
るように実施される。Ｃｏ量が３重量％未満では耐熱酸
化性の所要の向上が得られない。他方Ｃｏ量が５０重量
％を超えると、半田濡れ性が悪化すると共に、耐熱酸化
性も悪化する。Ｚｎ−Ｃｏ合金層の付着量が１００μｇ
／ｄｍ2 未満では、耐熱酸化性の向上が得られない。他
方５００μｇ／ｄｍ2 を超えると、Ｚｎ等の拡散により
導電性が悪化する。また、フラックスを使用しない工程
では、半田濡れ性を悪化することも予想される。付着量
は外観が銅色とあまり変わらないようにするためにも上
記のような薄いものとされる。According to the present invention, the Zn-Co alloy treatment is performed on the shiny surface of the copper foil, with or without the roughening treatment. Zn-Co alloy treatment is preferably 50-97 wt% using Zn-Co electroplating bath
The Zn-Co alloy layer containing Zn and 3 to 50% by weight of Co is formed so as to be very thin with an adhesion amount of 100 to 500 μg / dm 2 . If the amount of Co is less than 3% by weight, the required improvement in thermal oxidation resistance cannot be obtained. On the other hand, when the amount of Co exceeds 50% by weight, the solder wettability deteriorates and the thermal oxidation resistance also deteriorates. The amount of Zn-Co alloy layer deposited is 100 μg
If it is less than / dm 2 , the improvement in thermal oxidation resistance cannot be obtained. On the other hand, when it exceeds 500 μg / dm 2 , conductivity is deteriorated due to diffusion of Zn and the like. Further, it is expected that the solder wettability will be deteriorated in the process in which no flux is used. The adhered amount is made thin as described above so that the appearance is not so different from the copper color.
【００１５】Ｚｎ−Ｃｏめっき浴の組成及び条件例は次
の通りである： Ｚｎ：５〜５０g/l Ｃｏ：５〜５０g/l ｐＨ：２．５〜４ 温度：３０〜６０℃ 電流密度：０．５〜５A/dm2 めっき時間：１〜１０秒The composition and conditions of the Zn-Co plating bath are as follows: Zn: 5-50 g / l Co: 5-50 g / l pH: 2.5-4 Temperature: 30-60 ° C. Current density: 0.5-5 A / dm 2 Plating time: 1-10 seconds
【００１６】水洗後、Ｚｎ−Ｃｏ合金層上にＣｒ系防錆
層を形成するための防錆処理が実施される。Ｃｒ系防錆
層とは、クロム酸化物の単独皮膜処理或いはクロム酸化
物と亜鉛及び（又は）亜鉛酸化物との混合皮膜処理の単
独或いは組合せにより形成されたクロム酸化物を主体と
する防錆層を云う。クロム酸化物の単独皮膜処理に関し
ては、浸漬クロメート或いは電解クロメートいずれでも
良い。耐候性が要求されるときには、電解クロメートが
好ましい。浸漬クロメート或いは電解クロメートの条件
は斯界で確立されている条件に従う。例えば、浸漬クロ
メート及び電解クロメート処理の条件例は次の通りであ
る： （Ａ）浸漬クロメート処理 K2Cr2O7 ：０．５〜１．５g/l ｐＨ：１．４〜２．４ 温度：２０〜６０℃ 時間：３〜１０秒 （Ｂ）電解クロメート処理 K2Cr2O7 （Na2Cr2O7或いはCrO3）：２〜１０g/l NaOH或いはKOH ：１０〜５０g/l ｐＨ ：７〜１３ 浴温 ：２０〜８０℃ 電流密度 ：０．０５〜５ A/dm2 時間 ：５〜３０秒 アノード ：Pt-Ti 板、ステンレス鋼板等After washing with water, a rustproofing treatment is carried out to form a Cr-based rustproof layer on the Zn-Co alloy layer. The Cr-based rust preventive layer is a rust preventive agent mainly composed of chromium oxide formed by a single film treatment of chromium oxide or a mixed film treatment of chromium oxide with zinc and / or zinc oxide. Say a layer. For the single coating of chromium oxide, either immersion chromate or electrolytic chromate may be used. When weather resistance is required, electrolytic chromate is preferable. The conditions of immersion chromate or electrolytic chromate follow the conditions established in the art. For example, examples of conditions for immersion chromate treatment and electrolytic chromate treatment are as follows: (A) Immersion chromate treatment K 2 Cr 2 O 7 : 0.5 to 1.5 g / l pH: 1.4 to 2.4 Temperature : 20 to 60 ° C Time: 3 to 10 seconds (B) Electrolytic chromate treatment K 2 Cr 2 O 7 (Na 2 Cr 2 O 7 or CrO 3 ): 2 to 10 g / l NaOH or KOH: 10 to 50 g / l pH : 7 to 13 Bath temperature: 20 to 80 ° C Current density: 0.05 to 5 A / dm 2 hours: 5 to 30 seconds Anode: Pt-Ti plate, stainless steel plate, etc.
【００１７】クロム酸化物と亜鉛／亜鉛酸化物との混合
物皮膜処理とは、亜鉛塩または酸化亜鉛とクロム酸塩と
を含むめっき浴を用いて電気めっきにより亜鉛または酸
化亜鉛とクロム酸化物とより成る亜鉛−クロム基混合物
の防錆層を被覆する処理であり、電解亜鉛・クロム処理
と呼ばれる。めっき浴としては代表的には、K2Cr2O7、N
a2Cr2O7等の重クロム酸塩やCrO3等の少なくとも一種
と、水溶性亜鉛塩、例えばZnO 、ZnSO4 ・7H2O等少なく
とも一種と、水酸化アルカリとの混合水溶液が用いられ
る。代表的なめっき浴組成と電解条件例は次の通りであ
る： （Ｃ）電解亜鉛・クロム処理 K2Cr2O7 （Na2Cr2O7或いはCrO3）：２〜１０g/l NaOH或いはKOH ：１０〜５０g/l ZnO 或いはZnSO4 ・7H2O：０．０５〜１０g/l ｐＨ ：７〜１３ 浴温 ：２０〜８０℃ 電流密度 ：０．０５〜５ A/dm2 時間 ：５〜３０秒 アノード ：Pt-Ti 板、ステンレス鋼板等 クロム酸化物はクロム量として１５μg/dm2 以上そして
亜鉛は３０μg/dm2 以上の被覆量が要求される。粗面側
と光沢面側とで厚さを異ならしめても良い。こうした防
錆方法は、特公昭５８−７０７７、６１−３３９０８、
６２−１４０４０等に記載されている。クロム酸化物単
独の皮膜処理及びクロム酸化物と亜鉛／亜鉛酸化物との
混合物皮膜処理の組合せも有効である。The treatment of a mixture of chromium oxide and zinc / zinc oxide is carried out by electroplating zinc or zinc oxide and chromium oxide using a plating bath containing zinc salt or zinc oxide and chromate. This is a treatment for coating the rust preventive layer of the zinc-chromium group mixture, which is called electrolytic zinc-chromium treatment. The plating bath is typically K 2 Cr 2 O 7 , N
A mixed aqueous solution of at least one dichromate such as a 2 Cr 2 O 7 or CrO 3 and at least one water-soluble zinc salt such as ZnO or ZnSO 4 .7H 2 O and an alkali hydroxide is used. . Representative plating bath compositions and examples of electrolysis conditions are as follows: (C) Electrolytic zinc / chromium treatment K 2 Cr 2 O 7 (Na 2 Cr 2 O 7 or CrO 3 ): 2 to 10 g / l NaOH or KOH: 10 to 50 g / l ZnO or ZnSO 4 · 7H 2 O: 0.05~10g / l pH: 7~13 bath temperature: 20 to 80 ° C. current density: 0.05 to 5 A / dm 2 Time: 5 -30 seconds Anode: Pt-Ti plate, stainless steel plate, etc. Chromium oxide requires a chromium amount of 15 μg / dm 2 or more and zinc requires a coating amount of 30 μg / dm 2 or more. The rough surface side and the glossy surface side may have different thicknesses. Such rust prevention methods are disclosed in Japanese Examined Patent Publications Sho 58-7077, 61-33908,
62-14040 and the like. A combination of a coating of chromium oxide alone and a coating of a mixture of chromium oxide and zinc / zinc oxide is also effective.
【００１８】水洗及び乾燥後得られた銅箔は、従来の亜
鉛めっき＋クロメート処理の方法では、例えば２００℃
×３０分程度しか耐熱酸化性がなかったのに対して、２
４０℃×３０分或いは２７０℃×１０分の高温条件でも
変色しない耐熱酸化性を具備する。しかも、半田濡れ
性、レジスト密着性といった他の特性を損なうものでは
ない。The copper foil obtained after washing with water and drying is, for example, at 200 ° C. by the conventional zinc plating + chromate treatment method.
It had a resistance to heat and oxidation for only about 30 minutes, but it was 2
It has thermal oxidation resistance that does not discolor even under high temperature conditions of 40 ° C x 30 minutes or 270 ° C x 10 minutes. Moreover, it does not impair other properties such as solder wettability and resist adhesion.
【００１９】最後に、必要に応じ、銅箔と樹脂基板との
接着力の改善を主目的として、防錆層上の少なくとも粗
化面にシランカップリング剤を塗布するシラン処理が施
される。塗布方法は、シランカップリング剤溶液のスプ
レーによる吹付け、コーターでの塗布、浸漬、流しかけ
等いずれでもよい。例えば、特公昭６０−１５６５４号
は、銅箔の粗面側にクロメート処理を施した後シランカ
ップリング剤処理を行なうことによって銅箔と樹脂基板
との接着力を改善することを記載している。詳細はこれ
を参照されたい。Finally, if necessary, a silane treatment for applying a silane coupling agent to at least the roughened surface of the rust-preventive layer is performed for the main purpose of improving the adhesive force between the copper foil and the resin substrate. The coating method may be spraying of a silane coupling agent solution, coating with a coater, dipping, pouring, or the like. For example, Japanese Examined Patent Publication No. 60-15654 describes that the adhesion between the copper foil and the resin substrate is improved by subjecting the rough surface side of the copper foil to a chromate treatment and then a silane coupling agent treatment. . For details, refer to this.
【００２０】この後、必要に応じて、銅箔の延性を改善
する目的で焼鈍処理を施すこともある。Thereafter, if necessary, an annealing treatment may be performed for the purpose of improving the ductility of the copper foil.
【００２１】（実施例及び比較例）圧延銅箔に、光沢面
において、Ｚｎ−Ｃｏ合金（又はＺｎ単独）めっき→水
洗→Ｃｒ浸漬めっき→水洗→乾燥に手順で表面処理を施
した。一方、粗化面は、Ｃｕ−Ｎｉ処理を施し、その後
Ｃｒ浸漬めっきを行った。上記の（１）Ｚｎ−Ｃｏ合金
（又はＺｎ単独）めっき及び（２）Ｃｒ浸漬めっき並び
に（３）Ｃｕ−Ｎｉ合金めっきの条件は次の通りとし
た： （１）Ｚｎ−Ｃｏ合金（又はＺｎ単独）めっき Ｚｎ：２０g/l Ｃｏ：零又は１０g/l ｐＨ：３ 温度：４０℃ 電流密度：２A/dm2 めっき時間：１．５秒 （２）Ｃｒ浸漬めっき K2Cr2O7 ：１g/l ｐＨ：２．０ 温度：４０℃ 時間：５秒 （３）Ｃｕ−Ｎｉ合金めっき Ｃｕ：５〜１０g/l Ｎｉ：１０〜２０g/l ｐＨ：１〜４ 温度：２０〜４０℃ 電流密度：１０〜３０A/dm2 めっき時間：２〜５秒(Examples and Comparative Examples) The rolled copper foil was subjected to surface treatment in the order of Zn-Co alloy (or Zn alone) plating → washing → Cr dipping plating → washing → drying on the glossy surface. On the other hand, the roughened surface was subjected to Cu-Ni treatment and then Cr immersion plating. The conditions of the above (1) Zn-Co alloy (or Zn alone) plating, (2) Cr immersion plating, and (3) Cu-Ni alloy plating were as follows: (1) Zn-Co alloy (or Zn) Single) Plating Zn: 20g / l Co: Zero or 10g / l pH: 3 Temperature: 40 ° C Current density: 2A / dm 2 Plating time: 1.5 seconds (2) Cr dip plating K 2 Cr 2 O 7 : 1g / l pH: 2.0 Temperature: 40 ° C Time: 5 seconds (3) Cu-Ni alloy plating Cu: 5-10g / l Ni: 10-20g / l pH: 1-4 Temperature: 20-40 ° C Current density : 10 to 30 A / dm 2 Plating time: 2 to 5 seconds
【００２２】得られた製品の光沢面について、表面付着
量、ベーキングテスト及び半田濡れ性について試験を行
なった。尚、表面分折は、粗化面をＦＲ−４等の基板材
料でプレスしてマスキングし、酸に浸漬して光沢面のみ
のＺｎ及びＮｉを溶解させ、原子吸光法により分祈し
た。ベーキングテストは、銅箔６００ｍｍ巾×１００ｍ
ｍ長さの試片を所定のオーブン中に投入し、取り出した
後、光沢面の変色の有無を確認した（判断基準○＝変色
なし。×＝変色あり）。半田濡れ性については、フラッ
クスとして田村化研（株）製ＪＳ６４を使用して半田槽
にプレスした基板を垂直に浸漬し、基板表面に沿って吸
い上げられた半田の濡れ角度を求めた。角度が小いさい
程半田濡れ性が良い。The glossy surface of the obtained product was tested for surface adhesion, baking test and solder wettability. In the surface folding, the roughened surface was pressed with a substrate material such as FR-4 for masking, immersed in an acid to dissolve Zn and Ni only on the glossy surface, and separated by an atomic absorption method. Baking test is copper foil 600mm width x 100m
After the m-length test piece was put into a predetermined oven and taken out, the presence or absence of discoloration of the glossy surface was confirmed (judgment criterion ◯ = no discoloration. × = discoloration). Regarding the solder wettability, the pressed substrate was vertically dipped in a solder bath using JS64 manufactured by Tamura Kaken Co., Ltd. as a flux, and the wetting angle of the solder sucked along the substrate surface was obtained. The smaller the angle, the better the solder wettability.
【００２３】試験結果は次の通りである： No. Zn Co 付着量( μg/dm2 ) ベーキングテスト 半田濡れ性 (g/l) (g/l) Zn Co Cr 240oC/30min 270oC/30min 濡れ角 濡れ性 １ 20 0 230 -- 26 × × 39.5 100% ２ 20 10 230 23 30 ○ ○ 41.6 100%The test results are as follows: No. Zn Co adhesion amount (μg / dm 2 ) Baking test Solder wettability (g / l) (g / l) Zn Co Cr 240 o C / 30min 270 o C / 30min Wetting angle Wetting property 1 20 0 230 --26 × × 39.5 100% 2 20 10 230 23 30 ○ ○ 41.6 100%
【００２４】以上の試験結果から、次の事項が確認され
る。 Ｚｎめっき製品に対してＺｎ−Ｃｏめっき製品は皮膜
中にＣｏが約９％入った。 光沢面耐熱酸化性は、Ｚｎめっき品では変色したのに
対し、Ｚｎ−Ｃｏめっき品では変色せず、非常に良好で
ある。 半田濡れについては、いずれも差がほとんどなく、濡
れも１００％であることから問題がない。From the above test results, the following matters are confirmed. The Zn-Co plated product contained about 9% of Co in the coating as compared with the Zn plated product. The heat-resistant oxidation resistance on the glossy surface was very good, while the Zn-plated product discolored, whereas the Zn-Co plated product did not discolor. There is almost no difference in solder wetting, and there is no problem because wetting is 100%.
【００２５】[0025]
【発明の効果】従来の亜鉛めっき＋クロメート処理方法
製品よりも耐熱酸化性を改善した本発明品は、今後のプ
リント基板製造時の熱履歴に対しても銅箔光沢面の変色
を防止し、しかも半田濡れ性、レジスト密着性といった
他の特性を損なうことがなく、今後のプリント基板用銅
箔の要求に対処しうる。The product of the present invention, which has improved thermal oxidation resistance as compared with the conventional zinc plating + chromate treatment method product, prevents discoloration of the copper foil glossy surface against the heat history at the time of future printed circuit board manufacturing, Moreover, other characteristics such as solder wettability and resist adhesion are not impaired, and future demands for copper foils for printed circuit boards can be met.
Claims (3)
量％Ｚｎと３〜５０重量％Ｃｏとから成るＺｎ−Ｃｏ合
金層を１００〜５００μｇ／ｄｍ2 の付着量で形成し、
その後該Ｚｎ−Ｃｏ合金層上にＣｒ系防錆層を形成する
ことを特徴とする印刷回路用銅箔の表面処理方法。1. A Zn—Co alloy layer comprising 50 to 97% by weight Zn and 3 to 50% by weight Co is formed on the glossy surface of a copper foil for a printed circuit at an adhesion amount of 100 to 500 μg / dm 2 .
Thereafter, a Cr-based rust preventive layer is formed on the Zn-Co alloy layer, which is a surface treatment method for a copper foil for a printed circuit.
Ｆｅ、Ｃｏ及びＺｎから選択される１種乃至２種以上の
単一金属層又は合金層を形成するトリート処理を行なう
ことを特徴とする請求項１の印刷回路用銅箔の表面処理
方法。2. The roughened surface of the copper foil comprises Cu, Cr, Ni,
The surface treatment method for a copper foil for a printed circuit according to claim 1, wherein a treat treatment for forming one or more single metal layers or alloy layers selected from Fe, Co and Zn is performed.
クロメート処理によるクロム酸化物皮膜及び（或いは）
電解亜鉛・クロム処理によるクロム酸化物と亜鉛及び
（又は）亜鉛酸化物との混合皮膜から形成することを特
徴とする請求項１乃至２の印刷回路用銅箔の表面処理方
法。3. A chromium-based rust preventive layer and / or a chromium oxide film formed by immersion chromate treatment or electrolytic chromate treatment.
The method for surface treatment of a copper foil for a printed circuit according to claim 1 or 2, which is formed from a mixed film of chromium oxide and zinc and / or zinc oxide by electrolytic zinc / chromium treatment.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP35292291A JPH0732307B2 (en) | 1991-12-17 | 1991-12-17 | Surface treatment method for copper foil for printed circuits |
| TW081107613A TW230290B (en) | 1991-11-15 | 1992-09-25 | |
| MYPI92001742A MY109952A (en) | 1991-11-15 | 1992-09-29 | Surface treatment method of a copper foil for printed circuits. |
| EP92117930A EP0541997B1 (en) | 1991-11-15 | 1992-10-20 | Surface treatment method of a copper foil for printed circuits |
| DE69208324T DE69208324T2 (en) | 1991-11-15 | 1992-10-20 | Process for the surface treatment of a copper foil for printed circuits |
| US08/327,138 US5456817A (en) | 1991-11-15 | 1994-10-21 | Surface treatment method of a copper foil for printed circuits |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP35292291A JPH0732307B2 (en) | 1991-12-17 | 1991-12-17 | Surface treatment method for copper foil for printed circuits |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05167243A JPH05167243A (en) | 1993-07-02 |
| JPH0732307B2 true JPH0732307B2 (en) | 1995-04-10 |
Family
ID=18427376
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP35292291A Expired - Lifetime JPH0732307B2 (en) | 1991-11-15 | 1991-12-17 | Surface treatment method for copper foil for printed circuits |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0732307B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011004664A1 (en) | 2009-07-07 | 2011-01-13 | 日鉱金属株式会社 | Copper foil composite |
| WO2012132814A1 (en) | 2011-03-31 | 2012-10-04 | Jx日鉱日石金属株式会社 | Metallic foil composite, flexible printed circuit board using same, molded body, and manufacturing method for molded body |
| WO2012157469A1 (en) | 2011-05-13 | 2012-11-22 | Jx日鉱日石金属株式会社 | Copper foil complex, copper foil used in copper foil complex, molded body, and method for producing molded body |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000340911A (en) | 1999-05-25 | 2000-12-08 | Mitsui Mining & Smelting Co Ltd | Copper foil for printed wiring board |
| KR100491385B1 (en) * | 2001-07-04 | 2005-05-24 | 닛꼬 긴조꾸 가꼬 가부시키가이샤 | Copper alloy foil for laminated sheet |
| JP4808585B2 (en) * | 2006-10-19 | 2011-11-02 | 新日本製鐵株式会社 | Surface-treated metal material |
| CN112011810A (en) * | 2020-08-26 | 2020-12-01 | 九江德福科技股份有限公司 | Production method of high-heat-resistance electrolytic copper foil |
-
1991
- 1991-12-17 JP JP35292291A patent/JPH0732307B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011004664A1 (en) | 2009-07-07 | 2011-01-13 | 日鉱金属株式会社 | Copper foil composite |
| WO2012132814A1 (en) | 2011-03-31 | 2012-10-04 | Jx日鉱日石金属株式会社 | Metallic foil composite, flexible printed circuit board using same, molded body, and manufacturing method for molded body |
| WO2012157469A1 (en) | 2011-05-13 | 2012-11-22 | Jx日鉱日石金属株式会社 | Copper foil complex, copper foil used in copper foil complex, molded body, and method for producing molded body |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05167243A (en) | 1993-07-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5456817A (en) | Surface treatment method of a copper foil for printed circuits | |
| US5389446A (en) | Copper foil for printed circuits | |
| JP2849059B2 (en) | Processing method of copper foil for printed circuit | |
| US5700362A (en) | Method of treating copper foil for printed circuits | |
| US5071520A (en) | Method of treating metal foil to improve peel strength | |
| US5338619A (en) | Copper foil for printed circuits and method of producing same | |
| EP0618755A1 (en) | Copper foil for printed circuits and process for producing the same | |
| US5250363A (en) | Chromium-zinc anti-tarnish coating for copper foil having a dark color | |
| JP2517503B2 (en) | Surface treatment method for copper foil for printed circuits | |
| JP3032514B1 (en) | Copper foil excellent in oxidation resistance on glossy surface and method for producing the same | |
| JPH0654831B2 (en) | Method of treating copper foil for printed circuits | |
| US7037597B2 (en) | Copper foil for printed-wiring board | |
| JPH0685417A (en) | Surface treatment method for copper foil used for printed circuit | |
| JPH0732307B2 (en) | Surface treatment method for copper foil for printed circuits | |
| JPH0633467B2 (en) | Surface treatment method of rolled copper foil | |
| JPS587077B2 (en) | Copper foil for printed circuits and its manufacturing method | |
| JPS6133908B2 (en) | ||
| JP3113445B2 (en) | Copper foil for printed circuit and manufacturing method thereof | |
| JP3367805B2 (en) | Processing method of copper foil for printed circuit | |
| JPH0732306B2 (en) | Copper foil for printed circuit and manufacturing method thereof | |
| JPH0685455A (en) | Surface treatment of copper foil for printed circuit use | |
| JPH0654829B2 (en) | Method of treating copper foil for printed circuits | |
| JP2875186B2 (en) | Processing method of copper foil for printed circuit | |
| JP2875187B2 (en) | Processing method of copper foil for printed circuit | |
| JPH0774464A (en) | Copper foil for printed circuit and its manufacture |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19950919 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080410 Year of fee payment: 13 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090410 Year of fee payment: 14 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090410 Year of fee payment: 14 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100410 Year of fee payment: 15 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110410 Year of fee payment: 16 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110410 Year of fee payment: 16 |
|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313111 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110410 Year of fee payment: 16 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120410 Year of fee payment: 17 |
|
| EXPY | Cancellation because of completion of term | ||
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120410 Year of fee payment: 17 |