JPS59995B2 - Printed wiring board manufacturing method - Google Patents

Description

【発明の詳細な説明】 本発明は印刷配線板の製造方法に関するものであり、ク
ロム酸公害をなくし、かつクロム酸エッチングと同等の
性能を有する印刷配線板を提供することを目的とするも
のである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a printed wiring board, and its purpose is to eliminate chromic acid pollution and provide a printed wiring board that has performance equivalent to that of chromic acid etching. be.

絶縁基板上に印刷回路を設けた印刷配線板は電子機器の
小型化、軽量化、作業性向上のために極めて重要なもの
である。Printed wiring boards, in which printed circuits are provided on insulating substrates, are extremely important for making electronic devices smaller, lighter, and easier to work with.

この印刷配線板の製造方法として有力な手段の一つに添
加配線法印刷配線板の製造方法がある。即ち絶縁基板上
に化学めつき又は電気めつきによつて所要の回路を形成
する方法である。この方法はまず絶縁基板上に耐薬品性
のニトリルゴム変性フェノール樹脂接着剤を塗布し、こ
れをまず半硬化させる。One of the most effective methods for manufacturing printed wiring boards is the additive wiring method. That is, it is a method of forming a required circuit on an insulating substrate by chemical plating or electroplating. In this method, a chemical-resistant nitrile rubber-modified phenolic resin adhesive is first applied onto an insulating substrate, and then semi-cured.

次いでこの表面をクロム酸−硫酸混液で清浄し、塩化第
一錫及び塩化パラジウムを含む溶液で活性化させた後、
化学めつきを施して金属膜を形成する。しかる後電気め
つきを施して化学膜上の金属膜を生長させてから所要回
路部分だけ残して腐蝕除去する。次いで上記半硬化状態
の接着剤を硬化させ前記回路部分の金属膜を絶縁基板上
に強固に接着固定する方法である。しかしながらこの方
法は次の如き欠点がある。つまり、半硬化の接着剤を用
いるため、清浄化処理時に接着剤の溶解又は化学めつき
液中で接着剤に亀裂が発生しめつきのふくれが起こる。
また所定回路形成後接着剤を本硬化させるため硬化温度
等で接着剤の収縮が起こり密着性が損われ易いものであ
る。一方接着剤を完全硬化させクロム酸−硫酸混液の強
固な酸化溶解力を利用して接着剤表面を親水性にすると
共に極性基、投錨効果により絶縁基板と金属膜との密着
力を高める製造方法がある。しかるにこの方法は接着剤
を完全硬化させるため接着剤表面の活性に必ずクロム酸
−硫酸混液を用いなければならずクロム酸以外の酸化剤
では接着剤と化学めつき膜との密着力が弱いという欠点
を有するものである。The surface was then cleaned with a chromic acid-sulfuric acid mixture and activated with a solution containing stannous chloride and palladium chloride.
Chemical plating is applied to form a metal film. Thereafter, electroplating is applied to grow the metal film on the chemical film, and then the required circuit portions are removed by corrosion. Next, the semi-cured adhesive is cured to firmly adhere and fix the metal film of the circuit portion onto the insulating substrate. However, this method has the following drawbacks. That is, since a semi-cured adhesive is used, cracks occur in the adhesive during cleaning or in the chemical plating solution, causing blistering.
Furthermore, since the adhesive is fully cured after forming a predetermined circuit, the adhesive tends to shrink due to curing temperature, etc., and adhesion is likely to be impaired. On the other hand, a manufacturing method in which the adhesive is completely cured and the surface of the adhesive is made hydrophilic by utilizing the strong oxidative dissolving power of the chromic acid-sulfuric acid mixture, and the adhesion between the insulating substrate and the metal film is increased by the polar group and anchoring effect. There is. However, in this method, in order to completely cure the adhesive, a chromic acid-sulfuric acid mixture must be used to activate the adhesive surface, and oxidizing agents other than chromic acid have a weak adhesion between the adhesive and the chemically plated film. It has its drawbacks.

又周知の如くクロム酸は毒性が強く、公害処理設備に多
大な費用を要するものであり、クロム酸を用いない印刷
配線板の製造方法が望まれている。本発明はクロム酸公
害をなくし、かつ従来困難とされていたクロム酸以外の
エッチング液で処理しても接着剤と化学めつき膜の密着
力が強く、その他の特性においても従来のクロム酸エッ
チングと同等の性悪を有する印刷配線板の製造方法を提
供するものである。Furthermore, as is well known, chromic acid is highly toxic and requires a great deal of expense for pollution treatment equipment, so a method of manufacturing printed wiring boards that does not use chromic acid is desired. The present invention eliminates chromic acid pollution and maintains strong adhesion between the adhesive and chemically plated film even when treated with an etching solution other than chromic acid, which was considered difficult in the past. The purpose of the present invention is to provide a method for manufacturing a printed wiring board having properties equivalent to those described above.

熱硬化型接着剤を表面に塗布し、硬化させた絶縁基板を
、過マンガン酸カリ−隣酸系、あるいはアルカリ性過マ
ンガン酸カリ液で処理し、表面接着剤層を親水化処理し
た後、シランカップリング剤溶液中に浸漬し、その薄膜
を接着剤表面及び孔内壁に形成したのち周知の化学めつ
き処理を行うものである。A thermosetting adhesive is applied to the surface and the cured insulating substrate is treated with a potassium permanganate-phosphoric acid system or an alkaline potassium permanganate solution to make the surface adhesive layer hydrophilic, and then silane is applied. After being immersed in a coupling agent solution and forming a thin film on the surface of the adhesive and the inner wall of the hole, a well-known chemical plating process is performed.

即ち感応性附与工程、活性化処理工程を経た後、無電解
めつきの金属導電層を析出させ、さらに電気めつきを施
して所要回路を形成させるものである。実施例 １ 下記に示す熱硬化型接着剤を、絶縁基板の両面に塗布し
、７０〜１６０℃に段階的に加熱し完全硬化させる。That is, after passing through a sensitization step and an activation treatment step, a metal conductive layer is deposited by electroless plating, and further electroplating is performed to form a required circuit. Example 1 A thermosetting adhesive shown below is applied to both sides of an insulating substrate, and heated stepwise to 70 to 160°C to completely cure it.

メチルエチルケトンで２０％溶液とする 次に絶縁基板の所定印置に孔をあける。Make a 20% solution with methyl ethyl ketone. Next, holes are made at predetermined locations on the insulating substrate.

しかる後下記組成のエツチング液に１５分浸漬してから
十分水洗する。Thereafter, it is immersed in an etching solution having the composition shown below for 15 minutes, and then thoroughly washed with water.

次いでシランカツプリング剤溶液（例えば信越化学製Ｋ
ＢＭ−５０３の１％溶液）に浸漬し、接着剤の表面及び
孔内壁にンランカツプリング薄膜を形成し、室温で乾燥
さぜた後１０『Ｃ５分の加熱乾燥した。Next, a silane coupling agent solution (for example, K manufactured by Shin-Etsu Chemical Co., Ltd.
A thin coupling film was formed on the surface of the adhesive and on the inner wall of the hole, dried at room temperature, and then heated for 10 C5 minutes.

以下周知の芳法で化学めつき処理を行つた。即ち塩化第
一錫水溶液中に３分浸漬し十分水洗した後、さらに塩化
パラジウム水溶液中に３分浸漬し、接着剤表面及び孔内
壁を活性処理した。次に化学めつき浴に浸漬し化学銅又
は化学ニツケル皮膜を析出させた。次にめつき面に所定
の位置（非回路部）へ耐酸性塗料でマスキングした。The following chemical plating treatment was performed using a well-known method. That is, after being immersed in an aqueous solution of stannous chloride for 3 minutes and thoroughly washed with water, it was further immersed in an aqueous palladium chloride solution for 3 minutes to activate the adhesive surface and the inner wall of the hole. Next, it was immersed in a chemical plating bath to deposit a chemical copper or chemical nickel film. Next, predetermined positions (non-circuit areas) on the plating surface were masked with acid-resistant paint.

しかる後硫酸銅電気めつきを施して所要回路へ厚さ３０
〜４０μめつきした。次に非回路部のマスキング塗料を
除去したのち過硫酸アンモン液中に浸漬して非回路部の
化学めつき膜を除去し完成品とする。After that, copper sulfate electroplating is applied to the required circuit to a thickness of 30 mm.
~40μ plating was achieved. Next, after removing the masking paint on the non-circuit areas, it is immersed in an ammonium persulfate solution to remove the chemical plating film on the non-circuit areas, resulting in a finished product.

実施例 ２ ノ 上記接着剤を絶縁基板の両面に塗布し、完全硬化させる
。Example 2 The above adhesive is applied to both sides of an insulating substrate and completely cured.

次に絶縁基板の所定の印置に孔をあける。しかる後下記
組成のエツチング液に２０分浸漬してから十分水洗した
。過マンガン酸カリ４０ｆ／！溶液に苛性ソーダを添加
してペーパー（ＰＨ）を１２．０にしたのち７０℃に加
熱する。Next, holes are made at predetermined locations on the insulating substrate. Thereafter, it was immersed in an etching solution having the composition shown below for 20 minutes, and then thoroughly washed with water. Potassium permanganate 40f/! After adding caustic soda to the solution to adjust the paper (PH) to 12.0, the solution was heated to 70°C.

次にシランカツプリング剤溶液（信越化学製ＫＢＭ６Ｏ
２の１％水溶液）に浸漬し接着剤表面及び孔内壁にシラ
ンカツプリング薄膜を形成し、室温で乾燥後、１０『Ｃ
５分の加熱乾燥した。Next, silane coupling agent solution (KBM6O manufactured by Shin-Etsu Chemical Co., Ltd.
A thin silane coupling film was formed on the adhesive surface and the inner wall of the hole by immersing it in a 1% aqueous solution of
It was dried by heating for 5 minutes.

以下、実施例１と同一方法でめつきを施した。接着剤と
化学めつき膜との密着力（９０た剥離）は１．８〜２．
５Ｋｆ／（Ｖ７！あり又半田耐熱テスト（２６０゜Ｃ）
に対しても３０秒以上ある。なおシランカツプリング処
理を施さない接着剤の場合は密着力のばらつきが大きく
又密着力も弱く０，５〜１．２Ｋｆ／礪程度しかない。
以上のように本発明によれば、クロム酸一儲酸系のエツ
チング液を使用することなく、印刷配線板を製造できる
ので、クロム公害は生ぜず、環境汚染防止に役立つもの
であり、しかも完成した印刷配線板の品質も従来とかわ
らずすぐれたものである。Thereafter, plating was performed in the same manner as in Example 1. The adhesion strength (90° peeling) between the adhesive and the chemically plated film is 1.8 to 2.
5Kf/(V7! Also soldering heat resistance test (260°C)
It also takes more than 30 seconds. In the case of adhesives that are not subjected to silane coupling treatment, the adhesion strength varies greatly and is also weak, being only about 0.5 to 1.2 Kf/cm.
As described above, according to the present invention, printed wiring boards can be manufactured without using a chromic acid-based etching solution, so chromium pollution is not caused, and this is useful for preventing environmental pollution. The quality of printed wiring boards produced is as excellent as ever.

Claims (1)

【特許請求の範囲】[Claims] １ 絶縁基板の表面に接着剤を付し、この接着剤の表面
を酸化性薬品で粗化親水性に処理し、上記接着剤の表面
にシランカップリング剤の薄膜を形成して乾燥させ、上
記シランカップリング剤の表面を活性化した後、導電膜
を形成することを特徴とする印刷配線板の製造方法。1 Apply an adhesive to the surface of the insulating substrate, treat the surface of this adhesive with an oxidizing chemical to make it rough and hydrophilic, form a thin film of a silane coupling agent on the surface of the adhesive, dry it, and A method for manufacturing a printed wiring board, comprising activating the surface of a silane coupling agent and then forming a conductive film.