JP4610079B2 - Substrate partial plating method - Google Patents

Description

【００１４】
また、上記のポリ乳酸は単独で使用してもよいし、あるいはポリ乳酸を主成分とし、これに脂肪族ポリエステル（ポリヒドロキシカルボン酸、ヒドロキシカルボン酸又は脂肪族多価アルコールと脂肪族多価塩基酸とからなる脂肪族ポリエステル、ヒドロキシカルボン酸や脂肪族多価アルコールから選ばれる２種以上のモノマー成分と、脂肪族多価塩基酸から選ばれる２種以上のモノマー成分とからなるランダム共重合体やブロック共重合体等）の単独又は２種以上を、混合したものや、ランダム共重合又はブロック共重合させたものであってもよいし、また必要に応じてアルカリ分解促進剤、有機及び無機充填剤、可塑剤、湿潤剤、紫外線吸収剤、酸化防止剤、滑剤、着色剤等の汎用の合成樹脂に使用できる添加剤を混合したものであってもよい。
この脂肪族ポリエステルの混合量又は共重合量は、混合体又は共重合体の全量に対して１〜１０ｗｔ％程度、アルカリ分解促進剤の混合量は混合体全量に対して１〜１００ｗｔ％程度、好ましくは５〜８０ｗｔ％、より好ましくは１０〜６０ｗｔ％であり、その他の添加剤の混合量は混合体全量に対して１〜５％程度が適している。
【００１５】
なお、上記のポリ乳酸の重量平均分子量は、１万〜４０万程度が好ましく、脂肪族ポリエステルは、ポリ乳酸と混合させる場合の重量平均分子量は、１万〜５０万程度、好ましくは３万〜４０万程度、より好ましくは５万〜３０万程度が適しており、またポリ乳酸と共重合させる場合はその共重合体の重量平均分子量が、１万〜５０万程度、好ましくは３万〜４０万程度、より好ましくは５万〜３０万程度が適している。
また、上記のヒドロキシカルボン酸としては、グリコール酸、Ｌ−乳酸、Ｄ−乳酸、Ｄ／Ｌ−乳酸、３−ヒドロキシブチリックアシッド、４−ヒドロキシブチリックアシッド、３−ヒドロキシバレリックアシッド、５−ヒドロキシバレリックアシッド、６−ヒドロキシカプロン酸等が挙げられ、これらの１種以上が使用できる。
脂肪族多価アルコールとしては、エチレングリコール、ジエチレングリコール、トリエチレングリコール、ポリエチレングリコール、プロピレングリコール、ジプロピレングリコール、１，３−ブタンジオール、１，４−ブタンジオール、３−メチル−１，５−ペンタンジオール、１，６−ヘキサンジオール、１，９−ノナンジオール、ネオペンチルグリコール、ポリテトラメチレングリコール、１，４−シクロヘキサンジメタノール、１，４−ベンゼンジメタノール等が挙げられ、これらの１種以上が使用できる。
脂肪族多価塩基酸としては、コハク酸、シュウ酸、マロン酸、グルタル酸、アジピン酸、ピメリン酸、スベリン酸、アゼライン酸、セバシン酸、ウンデカン二酸、ドデカン二酸、フェニルコハク酸、１，４−フェニレンジ酢酸等が挙げられ、これらの１種以上が使用できる。
アルカリ分解促進剤としては、デンプン、ポリビニルアルコール、ポリエチレングリコール、ポリプロピレングリコール、ポリオキシテトラメチレングリコール等のポリアルキレングリコール、ポリアミノ酸等の親水性高分子化合物、無水コハク酸、ポリコハク酸イミド等のアルカリ加水分解性化合物等が挙げられ、これらの１種以上が使用できる。中でも、ポリ乳酸や脂肪族ポリエステルへの分散性や相溶性、あるいはブリードアウトのし難さ等から、ポリアルキレングリコール、特にポリエチレングリコールが好ましい。
【００１６】
以上の被覆材で基体を部分的に被覆するには、射出、押出、圧縮、鋳造、トランスファー、その他の種々の成形方法により被覆形状を成形する手法が挙げられるが、好ましくは基体を型の一部とする射出成形法により被覆材の射出と同時に基体表面の所望箇所を被覆する手法である。
【００１７】
上記被覆材を除去するには、水溶性高分子材料の場合は水を用いて行い、加水分解性高分子材料の場合はアルカリ水溶液や酸液（各種の無機酸の液）を用いて行う。
場合によっては、後述するメッキ用触媒の付与工程において、メッキ用触媒の付与と同時に被覆材の除去を行うことができる。
被覆材が水溶性高分子材料の場合、高分子材料の種類にもよるが、一般には、２５〜９５℃程度の温水中に２〜３５時間浸漬して除去するのが好ましい。
被覆材が加水分解性高分子材料、特にポリ乳酸の場合は、濃度２〜１５ｗｔ％程度で温度２５〜７０℃程度のカ性アルカリ（ＮａＯＨ、ＫＯＨ等）水溶液中に１〜１２０分程度浸漬して除去するのが好ましい。なお、カ性アルカリ水溶液が高温、高濃度程、被覆材ばかりか、メッキ用触媒をも脱落することがあるため、この程度の範囲で除去工程を行うことが好ましい。
【００１８】
〔基体表面の粗化〕
上記の基体の表面を粗化する方法としては、例えば、公知のエッチング方法が適用できる。
エッチング方法には、湿式と乾式とがあり、基体に使用されている材料の種類等により、適宜の方式のエッチング方法を採用すればよい。
乾式法は、例えば、プラズマを照射したり、気体を使用する等して行うことができる。
湿式法は、例えば、ＮａＯＨ、ＫＯＨ等のアルカリ金属水酸化物の水溶液、アルコール性ナトリウム、アルコール性カリウム等のアルカリ金属アルコラートの水溶液、あるいはジメチルホルムアミド等の有機溶剤を用い、これらのエッチング液を基体表面に塗布したり、これらの液中に基体を浸漬させる等して接触させて行うことができる。
このうち、ＮａＯＨ、ＫＯＨ等の水溶液を用いる方法は、濃度３５〜５０ｗｔ％程度、温度７０〜９５℃程度の条件とすることが好ましい。
また、アルカリ金属アルコラートの水溶液や、ジメチルホルムアミド等の有機溶剤を用いる方法は、水溶性又は加水分解性の高分子材料で被覆した後に粗化する場合に好適である。
なお、有機溶剤を使用する場合は、基体を膨潤するのみで、粗化まで至らないことがある。この場合は、有機溶剤での処理の後に、酸あるいはアルカリ処理を施せばよい。また、被覆工程後に、粗化を行う場合は、粗化工程で被覆材が完全には除去されないような条件とすることが必要であるが、ある程度除去されても問題ない。
【００１９】
なお、湿式法においては、上記のエッチング液と基体とを接触させた後に、塩酸やフッ酸等の酸溶液を用いて処理することが好ましい。この酸処理は、アルカリ性のエッチング液を単に中和するために行うのではなく、基体中に含まれるフィラーであって、かつ基体の表面近傍に存在しているフィラーの一部を除去し、基体表面の粗化効果をより一層高めるために行われる。
従って、この酸処理の条件（ｐＨ、温度、時間等）は、上記のフィラーが溶解する程度の条件とすることが好ましい。
また、湿式法は、上記のエッチング液と基体との接触の際、及び上記の酸溶液での処理の際に、基体を容器に入れ、この容器をエッチング液や酸溶液中に浸漬し、該液中で該容器を回転したり、揺動する等して行ってもよい。この容器は、多数の孔を穿設したバレル、球、箱状体のもの、あるいはカゴ状体のもの等が使用でき、その素材はポリプロピレン等の合成樹脂、あるいはフッ素系樹脂等で表面処理した金属等が使用できる。
【００２０】
〔メッキ用触媒〕
本発明におけるメッキ用触媒（以下、単に触媒と記すこともある）としては、公知のものが使用でき、中でもＰｄやＰｔを含むものが好ましく、これらは、例えば、塩化物等の無機塩として使用される。
メッキ用触媒の付与は、上記の無機塩を基体に付着させた後、アクセレータ処理により上記の触媒金属を析出させることで行われる。
無機塩を基体に付着させるには、無機塩の溶液と基体とを接触させればよく、例えば、無機塩の溶液中に基体を浸漬したり、この水溶液を基体に塗布する等して行われるが、本発明では、上記の粗化工程と同様に、基体を入れた上記のような容器を無機塩の溶液中に浸漬し、該溶液中で該容器を回転したり、揺動する等して行う。
具体的な条件は、基体の材料、メッキの材料、メッキ用触媒の材料、無機塩の付着方法等により種々異なり一概には決められないが、メッキ用触媒の塩として塩化パラジウムを使用し、浸漬法を採用する場合を例にとれば、一例として次のようなものが挙げられる。
【００２１】
触媒塩溶液組成
ＰｄＣｌ_２・２Ｈ_２Ｏ：０．１〜０．３ｇ／ｄｍ^３
ＳｎＣｌ_２・２Ｈ_２Ｏ：１０〜２０ｇ／ｄｍ^３
ＨＣｌ ：１５０〜２５０ｃｍ^３／ｄｍ^３
浸漬条件
温度：２０〜４５℃
時間：１〜１０分
【００２２】
なお、メッキ用触媒塩溶液の溶媒としては、上記の塩酸以外に、メタノール、エタノール、イソプロピルアルコール等の、上記した水溶性又は加水分解性高分子材料からなる被覆材を完全には溶出させない（一部は溶出してもよい）有機溶剤を用いることもできる。
【００２３】
上記のようなメッキ用触媒塩の付着の後、水洗し、アクセレータ処理してメッキ用触媒（金属）を基体上に析出させる。
アクセレータ処理は、一般には、アクセレータ（促進液）と触媒塩付与後の基体とを、浸漬あるいは塗布等により接触させて行うが、本発明では、触媒塩付与後の基体を入れた容器をアクセレータ液中に浸漬し、回転あるいは揺動する等して行う（なお、本発明では、上記のメッキ用触媒塩の付着、水洗、及びアクセレータ処理の全てを、基体を同一の容器に入れたままで行う）。
この促進液としては、硫酸、塩酸、水酸化ナトリウム、アンモニア等の無機溶液が用いられる。
上記組成の触媒塩溶液を用い、上記条件での浸漬で触媒塩が付与されている場合は、水洗により、基体表面に付着しているＳｎ^２＋−Ｐｄ^２＋の錯体が加水分解され、Ｓｎ^２＋はＳｎ（ＯＨ）Ｃｌとなって沈殿し、続いて行うアクセレータ処理により、Ｓｎ（ＯＨ）Ｃｌが溶解し、既に錯体状態が解かれているＰｄ^２＋と酸化還元反応を生起して、金属Ｐｄが基体上で生成する。この金属Ｐｄがメッキ用触媒として作用する。
【００２４】
なお、上記のアクセレータ処理の際に水溶性又は加水分解性の高分子材料からなる被覆材が溶出することもあるため、アクセレータ処理と同時に被覆材の除去を行ってもよいし、被覆材を除去した後にアクセレータ処理を行ってもよい。
もちろん、被覆材が完全に溶出する前に、アクセレータ処理を終了することもできる。
【００２５】
水溶性又は加水分解性の高分子材料による被覆材の厚さが１０〜１０００μｍ程度、好ましくは１０〜５００μｍ程度と薄い場合には、上記したメッキ用触媒塩の付着（例えば、上記Ｓｎ^２＋−Ｐｄ^２＋錯体の付着）、水洗（該錯体の加水分解により、Ｓｎ（ＯＨ）Ｃｌの沈殿生成）、アクセレータ処理（Ｓｎ（ＯＨ）Ｃｌが溶解し、水洗の際に錯体状態が解かれたＰｄ^２＋と酸化還元反応して金属Ｐｄを生成）と言う一連の操作からなるメッキ用触媒の付与工程において、被覆材が完全に溶出することもあり、メッキ用触媒の付与と同時に、被覆材の除去を行うことができる。
この場合、アクセレータ処理を、促進剤の温度を４０〜８０℃程度とし、該促進剤との接触時間を３０〜１２０分間程度とすることが好ましい。
また、基体の粗面化後に、基体を型の一部とする射出成形法により被覆材を設ける場合にあっては、基体と型とを密に接触させると、基体に設けた凹凸（粗面）が消失する懸念があるため、基体と型との間に微小な隙間を空けて射出成形型を構成し、この微小な隙間（本来的には被覆材を必要としない部分）にも被覆材を成形（すなわち、バリを形成）することがある。この微小な隙間の被覆材（バリ）は、極めて薄いため、上記のメッキ用触媒の付与工程中において、被覆材が完全に溶出させることができる。
以上のように、メッキ用触媒の付与工程と被覆材の除去工程とを同時に行うことは、工程面での効果のみならず、基体の粗面化面の保護、延いては高精度でのメッキ施工と言った効果をも得ることができる。
【００２６】
〔メッキ〕
本発明におけるメッキ方法は、公知のメタライジング方法（無電解メッキ方法や電気メッキ方法）が採用できる。
メッキ金属としては、銅、錫、鉛、ニッケル、金、その他各種の金属が挙げられる。
メッキ工程は、多数回に分けて行うこともできるし、１回で一度に行うこともできる。
なお、触媒付与工程の後に、予備メッキ工程を設けることもできる。予備メッキも、公知のメタライジング法で行うことができ、好ましくは無電解メッキ法であり、メッキ金属も、上記のいわゆる本メッキ工程での金属と同様のものが使用できる。この予備メッキ工程を設けることにより、本メッキ工程でのメッキ品質を一層良好なものとすることができる。
また、後メッキ工程を設けることもできる。後メッキ工程も、公知のメタライジング法で行うことができ、好ましくは無電解メッキ法であり、メッキ金属は、本メッキ工程での金属と同種であってもよいが、異種のものであってもよい。
【００２７】
〔メッキ材の除去〕
メッキ材の除去は、上記のようなメッキ金属を除去することができる手法であれば、どのような方法によってもよいが、一般には、塩化第二鉄、塩化第二銅などの無機塩の溶液と、メッキ施工面とを、浸漬あるいは塗布等により接触させて行うが、本発明では、上記の粗化工程やメッキ用触媒付与工程と同様に、メッキ後の基体を入れた上記のような容器を無機塩の溶液中に浸漬し、回転あるいは揺動する等して行うことが好ましい。
〔アニール処理〕
本発明では、以上の各工程が終了した後、アニール処理を行うこともできる。
このアニール処理により、メッキ被膜の密着力を更に向上させることができる。
アニール処理の条件は、１６０〜１７５℃で、１〜５時間保持の後、室温まで徐々に冷却することが好ましい。
【００２８】
【実施例】
実施例１
〔基体の成形工程〕
芳香族系ポリエステル（液晶ポリマー《米国セラニース社製商品名“ベクトラＣ８１０”を使用》）により、１次金型を用いて、図１（Ａ）（斜視図），（Ｂ）（（Ａ）の一部切欠図）に示す形状の基体（単品）１を成形した。
この基体１は、５０×３０×５（ｍｍ）の外形寸法を有し、図示するように、天面の対角線上の位置に、２個の貫通孔（Ｔｈｒｏｕｇｈ Ｈｏｌｅ）２，２を有している。
この基体１の複数個を多数の孔を穿設したポリプロピレン製のバレル状容器に入れ、この容器を回転させつつ、６０℃に加熱した脱脂液（奥野製薬社製商品名“エースクリーンＡ２２０”５０ｇ／リットル《以下、リットルをＬと、ミリリットルをｍＬと記す》水溶液）に１０分間浸漬した後、水洗して脱脂した。
【００２９】
〔基体表面の粗化工程〕
メチルアルコール１Ｌに金属Ｎａ３５０〜５００ｇ（本例では４３０ｇ）を溶解したアルカリ溶液を９０℃に加熱し、この加熱溶液中に、上記脱脂後の基体１の複数個を、上記のバレル状容器に入れたままで浸漬し回転しながら、３０〜８０分間（本例では４０分間）保持して、基体１の表面を粗化した。
なお、メチルアルコールに変えてエチルアルコール（金属Ｎａ４３０ｇ）を使用した場合も、同様の条件で粗化することができた。
また、メチルアルコールに変えてイソプロピルアルコール（金属Ｎａ４３０ｇ）を使用した場合は、このアルカリ溶液を６０℃に加熱し、この溶液に上記脱脂後の基体１の複数個を上記のバレル状容器に入れたままで浸漬し回転しながら１０分間保持の後、クロム酸混液（ＣｒＯ_３２２ｗｔ％と濃硫酸５４ｗｔ％の混合溶液）を６０℃に加熱した中にバレル状容器のままで回転しながら入れることにより、粗化することができた。
更に、水１ＬにＮａＯＨ３５０〜５００ｇ（本例では４００ｇ）を溶解したアルカリ溶液を使用した場合は、上記のメチルアルコールを使用した場合と同様の条件で粗化することができた。
【００３０】
〔基体の被覆工程〕
表面粗化後の基体１をセットし５〜３０℃（本例では１０℃）に保持した２次金型内に、１５０〜２６０℃（本例では１９０℃）に加熱した被覆材３としての水溶性高分子材（ポリビニルアルコール《以下、ＰＶＡ》《クラレ社製商品名“ポバール”を使用》）を、射出圧２００〜１２００ｋｇ／ｃｍ^２（本例では３５０ｋｇ／ｃｍ^２）で射出し、図２（斜視図）に示す態様の部分被覆３成形品を得た。
この成形品の被覆材３の厚さは、１ｍｍと、０．５ｍｍとした。
【００３１】
〔メッキ用触媒の付与工程および被覆材の除去工程〕
メチルアルコールに、メッキ用触媒塩としての塩化第一スズと塩化パラジウムとの混合塩酸液（荏原ユージライト社製商品名“エニレックスＣＴ−８”）を２０ｍＬ／Ｌの割合で添加し、これを３０℃に保持し、この溶液中に、上記の部分的被覆成形品の複数個を上記と同様のバレル状容器に入れ、この容器を３〜５分間（本例では４分間）回転しながら浸漬した後、水洗し、６０℃に加温した塩酸（５０ｍＬ／Ｌ）中に６０分間浸漬（アクセレータ処理）し、部分被覆成形品の被覆材３以外の部分にメッキ用触媒を付与すると共に、被覆材３の溶解除去を行った。
被覆材３の厚さが１ｍｍ、０．５ｍｍの何れの場合も、メッキ用触媒の付与と被覆材３の除去とが同時に良好に行われた。
【００３２】
〔メッキ工程〕
被覆材３除去後の基体１の複数個を上記のバレル状容器に入れたままで、表１に示す組成の銅メッキ浴中に浸漬し回転させながら、表２に示すメッキ条件で、該基体１に厚さ０．３〜２０．０μｍ（本例では１０μｍ）となるように、無電解銅メッキを施した後、１７０℃で１時間保持し、室温まで徐冷するというアニール処理を行って図３に示す態様のものを得た。
また、無電解銅メッキを０．５μｍ厚さとなるように施した後、上記のバレル状容器に入れたままで、電気銅メッキを０．５μｍ厚さとなるように施し、次いで上記と同様のアニール処理を行った場合も、同様の態様のものを得た。
なお、図３中、符号４で示す部分が銅メッキが施された部分であり、図３に示すように、この銅メッキ４は、メッキ用触媒付与面のみ、すなわち図２に示した被覆材３で覆われていた部分以外の部分と、貫通孔２内の表面に施されていた。
【００３３】
【表１】
銅メッキ浴組成
ＣｕＳＯ_４・５Ｈ_２Ｏ：０．０４モル／Ｌ
ＨＣＨＯ ：０．１モル／Ｌ
ＮａＯＨ ：０．２モル／Ｌ
ＥＤＴＡ・４Ｎａ ：０．０８モル／Ｌ
α，α′−ジピリジル：５〜１０ｐｐｍ
ＰＥＧ−１０００^＊１ ：５０〜１００ｐｐｍ
＊１ＰＥＧ−１０００：安定剤（荏原ユージライト社製商品名）
【００３４】
【表２】
メッキ条件
浴温度 ：６０〜７０℃
エア攪拌：０．１Ｌ／Ｌ・分
浴 ：０〜１ｄｍ^２／Ｌ
【００３５】
比較例１
〔基体の成形工程〕
実施例１と同様にして図４に示す形状の基体（単品）１１を成形した。１２は貫通孔を示し、１１′は基体１１の凹部を示す。
【００３６】
〔基体表面の粗化工程〕
この基体１１を実施例１と同様にして粗化した。
【００３７】
〔メッキ用触媒の付与工程〕
濃度が１５０ｍＬ／Ｌの濃硫酸中に、メッキ用触媒塩として実施例１と同様の荏原ユージライト社製商品名“エニレックスＣＴ−８”を２０ｍＬ／Ｌの割合で混合し、３０℃に保持した溶液中に、表面粗化した１次成形品１１を、実施例１と同様にして、３分間浸漬した後、水洗し、濃度が８０ｍＬ／Ｌの硫酸からなるアクセレータ液を５０℃に保持し、この液中に４分間浸漬し、水洗して、基体１１の全面にメッキ用触媒を付与した。
【００３８】
〔基体の被覆工程〕
メッキ用触媒付与後の基体１１を２次金型内にセットし、基体１１と同じ樹脂により、図５に示す態様の部分的被覆成形品（図４の凹部１１′に基体１１と同じ樹脂による被覆材１３が成形されたもの）を得た。
【００３９】
〔メッキ工程〕
この部分的被覆成形品に、実施例１と同様にして無電解銅メッキを施した。
この銅メッキは、基体１１と被覆材１３の密着が不良であるため、この界面のメッキ用触媒付与面が覗いている部分にも、施されていることが視認できた。
【００４０】
実施例２
〔基体の成形工程〕
実施例１と同様にして実施例１と同様の基体１を成形した。
【００４１】
〔基体表面の粗化工程〕
この基体１を実施例１と同様にして粗化した。
【００４２】
〔基体の被覆工程〕
表面粗化後の基体１をセットし５〜３０℃（本例では１０℃）に保持した２次金型内に、１５０〜２６０℃（本例では１９０℃）に加熱した被覆材３としての加水分解性高分子材（ポリ乳酸樹脂《三井化学社製商品名“ＬＡＣＥＡ”を使用》）を、射出圧２００〜１２００ｋｇ／ｃｍ^２（本例では３５０ｋｇ／ｃｍ^２）で射出し、図２（斜視図）に示す態様の部分被覆３成形品を得た。この成形品の被覆材３の厚さは１．５ｍｍであった。
【００４３】
〔メッキ用触媒の付与工程〕
水に、メッキ用触媒塩として実施例１と同様の荏原ユージライト社製商品名“エニレックスＣＴ−８”を２０ｍＬ／Ｌの割合で添加し、更にＨＣｌを１５０ｍＬ／Ｌの割合で添加し、これを３０℃に保持し、この溶液中に、上記の部分的被覆成形品を、実施例１と同様にして、３〜５分間（本例では４分間）浸漬した後、水洗し、３０℃に加温した塩酸（５〜１０％、本例では８％）中に４分間浸漬（アクセレータ処理）し、部分被覆成形品の被覆材３以外の部分にメッキ用触媒を付与した。
【００４４】
〔被覆材の除去工程〕
メッキ用触媒を付与した後の基体１を、実施例１と同様にして、濃度７ｗｔ％で３０℃のＮａＯＨ水溶液中に４０分間浸漬して、被覆材３を除去した。
【００４５】
なお、ポリ乳酸による被覆材３の厚さを実施例１と同じ１ｍｍと、０．５ｍｍとした場合は、いずれの場合も、上記のメッキ用触媒の付与工程において、メッキ用触媒の付与と同時に被覆材３の除去を行うことができた。
【００４６】
〔メッキ工程〕
この部分的被覆成形品に、実施例１と同様にして無電解銅メッキを施した。
また、実施例１と同様にして、無電解銅メッキを施した後、電気銅メッキを施した。
いずれの場合も、実施例１と同様に、メッキ用触媒付与面のみ、すなわち図２に示した被覆材３で覆われていた部分以外の部分と、貫通孔２内の表面に、銅メッキ４が施されていた。
【００４７】
実施例３
〔基体の成形工程〕
実施例１と同様にして実施例１と同様の基体１を成形した。
【００４８】
〔基体の被覆工程〕
この基体１をセットし、実施例２と同様にして加水分解性樹脂を射出し、実施例１と同様の部分的被覆成形品を得た。
【００４９】
〔基体表面の粗化工程〕
上記の部分的被覆成形品を、３５〜６０℃（本例では５０℃）に加温した濃度６０〜８０％（本例では５０％）のジメチルホルムアミド溶液に、実施例１と同様にして、５〜１２０分間（本例では６０分間）浸漬して、被覆材３以外の部分すなわち基体１の表面を膨潤させた後、水洗し、次いで７０〜７５℃（本例では７０℃）に加熱した濃硫酸（６００ｃｍ^３／ｄｍ^３）・８９％リン酸（１００ｃｍ^３／ｄｍ^３）・クロム酸（３０ｇ／ｄｍ^３）に３０〜１２０分間（本例では７０分間）浸漬して、この膨潤部分を粗化した。
【００５０】
〔メッキ用触媒の付与工程〕
エチルアルコールに、メッキ用触媒塩としての塩化パラジウム（奥野製薬社製）を３０ｍＬ／Ｌの割合で添加した溶液を、５０〜９０℃（本例では６０℃）に加熱し、この溶液中に、実施例１と同様にして、上記の表面粗化後の成形品を１５〜１００分間（本例では６０分間）浸漬した後、水洗して、上記の表面粗化部分、すなわち被覆材３以外の部分にメッキ用触媒を付与した。
【００５１】
〔被覆材の除去工程〕
触媒付与後の成形品を、実施例１と同様にして、２０〜８０℃（本例では５０℃）の５〜２０％（本例では５％）苛性ソーダ溶液に４０〜８０分間（本例では６０分間）浸漬し、被覆材３を加水分解して除去した。
【００５２】
〔メッキ工程〕
実施例１と同様にして無電解銅メッキ４を施した。
この銅メッキ４は、実施例１の場合と同様に、被覆材３で覆われていた部分以外の部分と、貫通孔２内の表面に施されていた。
【００５３】
実施例４
〔基体の成形工程〕
実施例１と同様にして実施例１と同様の基体１を成形した。
【００５４】
〔基体表面の粗化工程〕
実施例１と同様にして基体１の全面を粗化した。
【００５５】
〔メッキ用触媒の付与工程〕
実施例１と同様にして基体１の全面にメッキ用触媒を付与した。
【００５６】
〔メッキ工程〕
アニール処理を行わない以外は実施例１と同様にして、厚さ５μｍの無電解銅メッキを施した。
【００５７】
〔被覆工程〕
メッキを施した後の基体に、実施例２で用いたものと同じ加水分解性樹脂により、実施例１と同様にして、部分的被覆（メッキを残す部分への被覆）成形品を得た。
【００５８】
〔メッキ材の除去工程〕
塩化第二鉄又は塩化第二銅（２８〜４２ｗｔ％《本例では４０ｗｔ％》）溶液中に、実施例１と同様にして、被覆工程後の成形品を浸漬して、被覆されていない部分のメッキ材を除去した。
【００５９】
〔被覆材の除去工程〕
実施例２と同様にして被覆材を加水分解して除去した後、実施例１と同様のアニール処理を行った。
【００６０】
実施例５
〔基体の成形工程〕
実施例１と同様にして実施例１と同様の基体１を成形した。
【００６１】
〔基体表面の粗化工程〕
実施例１と同様にして基体１の全面を粗化した。
【００６２】
〔メッキ用触媒の付与工程〕
実施例１と同様にして基体１の全面にメッキ用触媒を付与した。
【００６３】
〔基体の被覆工程〕
実施例２で用いたものと同じ加水分解性樹脂により、実施例１と同様にして、実施例１と同様の部分的被覆成形品を得た。
【００６４】
〔メッキ工程〕
アニール処理を行わない以外は実施例１と同様にして、厚さ１〜５μｍの無電解銅メッキを施した。
【００６５】
〔被覆材の除去工程〕
６０〜９０℃の４〜２５％苛性ソーダ溶液に、実施例１と同様にして、１〜３時間浸漬し、被覆材を加水分解して除去した。
【００６６】
〔後メッキ工程〕
無電解銅メッキが施された成形品の全面に、再度、実施例１と同様にして、厚さ１〜２０μｍの無電解銅メッキを施した。
【００６７】
実施例６
被覆材としてＰＶＡを使用すること、メッキを塩化アルミニウムと水酸化リチウムアルミニウムをテトラヒドロフラン溶液中で処理して厚さ０．５〜２．５μｍ（本例では２μｍ）のアルミニウムメッキを得ること以外は、実施例４を繰り返した。
【００６８】
実施例７
〔基体の成形工程〕
芳香族系ポリエステル（液晶ポリマー《米国セラニース社製商品名“ベクトラＣ８１０”を使用》）により、１次金型を用いて、図６（斜視図）に示す形状の基体（集合基体）２１を成形した。
この基体２１の外形寸法は、ａ≒４０ｍｍ、ｂ≒５ｍｍ、ｃ≒４ｍｍ、ｄ≒７ｍｍ、ｅ≒２ｍｍであり、図示するように、天面に、２本の直線状に、複数個の貫通孔（Ｔｈｒｏｕｇｈ Ｈｏｌｅ）２，２，・・・を有している。
この集合基体２１の複数個を多数の孔を穿設したポリプロピレン製のバレル状容器に入れ、この容器を回転させつつ、６０℃に加熱した脱脂液（奥野製薬社製商品名“エースクリーンＡ２２０”５０ｇ／Ｌ水溶液）に１０分間浸漬した後、水洗して脱脂した。
【００６９】
〔基体表面の粗化工程〕
メチルアルコール１Ｌに金属Ｎａ４３０ｇを溶解したアルカリ溶液を９０℃に加熱し、この加熱溶液中に、上記脱脂後の基体２１の複数個を、上記のバレル状容器に入れたままで浸漬し回転しながら、４０分間保持して、基体２１の表面を粗化した。
なお、メチルアルコールに変えてエチルアルコール（金属Ｎａ４３０ｇ）を使用した場合も、同様の条件で粗化することができた。
また、メチルアルコールに変えてイソプロピルアルコール（金属Ｎａ４３０ｇ）を使用した場合は、このアルカリ溶液を６０℃に加熱し、この溶液に上記脱脂後の基体２１の複数個を上記のバレル状容器に入れたままで浸漬し回転しながら１０分間保持の後、クロム酸混液（ＣｒＯ_３２２ｗｔ％と濃硫酸５４ｗｔ％の混合溶液）を６０℃に加熱した中にバレル状容器のままで回転しながら入れることにより、粗化することができた。
更に、水１ＬにＮａＯＨ４００ｇを溶解したアルカリ溶液を使用した場合は、上記のメチルアルコールを使用した場合と同様の条件で粗化することができた。
【００７０】
〔基体の被覆工程〕
表面粗化後の基体２１をセットし１０℃に保持した２次金型内に、１９０℃に加熱した被覆材３としての加水分解性高分子材（ポリ乳酸樹脂《三井化学社製商品名“ＬＡＣＥＡ”を使用》）を、射出圧３５０ｋｇ／ｃｍ^２で射出し、図７（Ａ）（全体斜視図），（Ｂ）（図７（Ａ）のα−α線切断部の説明図），（Ｃ）（図７（Ｂ）の一部切欠図）に示す態様の部分被覆３成形品（集合成形品）を得た。この成形品の被覆材３の厚さは、１ｍｍと、０．５ｍｍとした。
【００７１】
〔メッキ用触媒の付与工程および被覆材の除去工程〕
メチルアルコールに、メッキ用触媒塩としての塩化第一スズと塩化パラジウムとの混合塩酸液（荏原ユージライト社製商品名“エニレックスＣＴ−８”）を２０ｍＬ／Ｌの割合で添加し、これを３０℃に保持し、この溶液中に、上記の部分的被覆成形品の複数個を上記と同様のバレル状容器に入れ、この容器を４分間回転しながら浸漬した後、水洗し、６０℃に加温した塩酸（５０ｍＬ／Ｌ）中に６０分間浸漬（アクセレータ処理）し、部分被覆成形品の被覆材３以外の部分にメッキ用触媒を付与すると共に、被覆材３の溶解除去を行った。
被覆材３の厚さが１ｍｍ、０．５ｍｍの何れの場合も、メッキ用触媒の付与と被覆材３の除去とが同時に良好に行われた。
【００７２】
〔メッキ工程〕
被覆材３除去後の基体２１の複数個を上記のバレル状容器に入れたままで、表３に示す組成の予備メッキ浴中に浸漬し回転させながら、同表に示すメッキ条件で、該基体２１に厚さ０．５〜１．５μｍ（本例では１μｍ）となるように、無電解銅メッキを施した後、表４に示す組成の本メッキ浴中に浸漬し回転させながら、同表に示すメッキ条件で、上記の予備メッキ上に厚さ９．５〜８．５μｍ（本例では９μｍ）となるように、無電解銅メッキを施し、全体のメッキ厚さ１０μｍとした。
なお、この銅メッキの後、無電解Ｎｉメッキ・無電解Ａｕメッキ、あるいは電気Ｎｉメッキ・電気Ａｕメッキ等の後メッキを施すこともできるし、最終工程として実施例１と同様のアニール処理を行うこともできる。
図８の断面図に、本例でメッキが施された部分を概略的に示す。図８中、符号４で示す部分が銅メッキ（あるいは銅メッキ後に、Ｎｉメッキ・Ａｕメッキ等の後メッキ）が施された部分であり、同図に示すように、このメッキ４は、メッキ用触媒付与面のみ、すなわち図７（Ａ）〜（Ｃ）に示した被覆材３で覆われていた部分以外の部分と、貫通孔２内の表面に施されていた。
【００７３】
【表３】
予備（銅）メッキ浴組成・条件
ＣｕＳＯ_４・５Ｈ_２Ｏ ：０．０４モル／Ｌ
ＨＣＨＯ（３７％溶液）：０．３モル／Ｌ
ＮａＯＨ ：ｐＨ１２．２
ＥＤＴＡ・４Ｎａ ：０．１０モル／Ｌ
安定剤^＊１ ：若干
浴温度 ：３５℃
＊１安定剤：金属（メタルイオン）系
【００７４】
【表４】
本（銅）メッキ浴組成・条件
ＣｕＳＯ_４・５Ｈ_２Ｏ ：０．０４モル／Ｌ
ＨＣＨＯ（３７％溶液）：０．０６モル／Ｌ
ＮａＯＨ ：ｐＨ１２
ＥＤＴＡ・４Ｎａ ：０．１モル／Ｌ
安定剤^＊１ ：若干
浴温度 ：６５℃
メッキ速度 ：２．５μｍ／ｈｒ
【００７５】
その後、図６に点線で示す仮想線に沿ってカットし、図９（斜視図）に示す形状のチップ部品を得た。
【００７６】
実施例８
実施例７の集合基体２１を用い、図７（Ａ）〜（Ｃ）に示す態様で被覆し、実施例７の表３に示す予備メッキ浴組成・条件及び表４に示す本メッキ浴組成・条件とする以外は、実施例３と同様の工程に沿ってメッキを施した後、実施例７と同様にしてカットして図９（斜視図）に示す形状のチップ部品を得た。
【００７７】
実施例９
実施例７の集合基体２１を用い、図７（Ａ）〜（Ｃ）に示す態様で被覆し、実施例７の表３に示す予備メッキ浴組成・条件及び表４に示す本メッキ浴組成・条件とする以外は、実施例４と同様の工程に沿ってメッキを施した後、実施例７と同様にしてカットして図９（斜視図）に示す形状のチップ部品を得た。
【００７８】
実施例１０
実施例７の集合基体２１を用い、図７（Ａ）〜（Ｃ）に示す態様で被覆し、実施例７の表３に示す予備メッキ浴組成・条件及び表４に示す本メッキ浴組成・条件とする以外は、実施例５と同様の工程に沿ってメッキを施した後、実施例７と同様にしてカットして図９（斜視図）に示す形状のチップ部品を得た。
【００７９】
実施例１１
被覆材としてＰＶＡを使用すること、メッキを塩化アルミニウムと水酸化リチウムアルミニウムをテトラヒドロフラン溶液中で処理して厚さ０．５〜２．５μｍ（本例では２μｍ）のアルミニウムメッキを得ること以外は、実施例９を繰り返した。
【００８０】
【発明の効果】
本発明によれば、従来のレジストの塗布・硬化・除去工程を省略することができ、従って有機溶剤による環境問題の懸念もないし、工程を短縮することもできる。
また、寸法精度が高く、かつ導電率の高い、高品質の電子・電気部品を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施例で用いた基体の形状の一例を示す図で、（Ａ）が斜視図、（Ｂ）が（Ａ）の一部切欠図である。
【図２】図１の基体に被覆材を施した状態の一例を示す斜視図である。
【図３】図１のものに無電解メッキを施した状態の一例を示す斜視図である。
【図４】本発明の比較例で用いた基体の一例を示す図である。
【図５】図４の基体に被覆材を施した状態の一例を示す斜視図である。
【図６】本発明の他の実施例で用いた集合基体の形状の一例を示す斜視図である。
【図７】図６の集合基体に被覆材を施した状態の一例を示す図であり、（Ａ）がその全体の斜視図、（Ｂ）が（Ａ）のα−α線切断部の説明図、（Ｃ）が（Ｂ）の一部切欠図である。
【図８】図７の被覆材を施した場合の図６の集合基体にメッキを施した状態を示す一部断面図である。
【図９】図８の状態でメッキが施された集合メッキ製品を各チップ部品にカットした状態を示す斜視図である。
【符号の説明】
１，１１，２１ 基体
２，１２ 孔
３，１３ 被覆材
４ メッキ[0001]
BACKGROUND OF THE INVENTION
  The present invention is a substrate made of synthetic resin or other material.(ChiAn assembly base in which a large number of substrate parts are assembled.body)In particular, the present invention relates to a method for partially plating the above-mentioned substrate for manufacturing electronic / electrical components such as printed circuit boards and lead frame insert molded circuit components.
[0002]
[Technical background]
Conventionally, as a method of partially plating a synthetic resin substrate (molded product),
(1) After roughening the surface of the molded product (for example, etching) and applying a catalyst for plating based on Pd, Pt, etc., leave a portion to be plated and resist by silk printing or dispenser coating Applying, then plating and removing the resist,
(2) Insert the molded article after applying the catalyst into a mold, and inject (inject) plastic, rubber or the like (electrical insulating material) into the mold, A method of coating, then plating, and removing the coating material if necessary,
Etc. are known (CMC Co., Ltd., “Composite Technology for Plastic Molding” P260-275, JP-A-7-316825, JP-A-63-4092, JP-A-2592243, etc.).
[0003]
However, in the method (1), a resist curing step by heat drying or the like is necessary after resist application. In addition, when removing the resist after plating, it is necessary to use an organic solvent such as methylene chloride, which, like chlorofluorocarbon (CFC), is considered a cause of ozone layer destruction and is discarded. If this increases, there is a concern that skin cancer and cataracts will increase, or ecosystems such as plants and plankton will be destroyed.
In the method (2), since the adhesion of the coating material is low, the plating solution enters the boundary surface of the coating material, and the dimensional accuracy is low. Moreover, when removing a coating | covering material as needed, there exists a concern similar to said resist.
In addition, in both methods (1) and (2), since the catalyst for plating is applied to the entire surface of the molded product, the electrical surface resistance value after plating, that is, after circuit molding is low.
[0004]
OBJECT OF THE INVENTION
The present invention is a method for plating a substrate made of a synthetic resin or other material, which does not have a resist coating / curing / removing process, and therefore has no concern about environmental problems due to organic solvents, and can shorten the process, Moreover, it is an object of the present invention to provide a partial plating method on a substrate, which can be a high-quality electronic / electrical part with high dimensional accuracy and high electrical conductivity.
[0005]
SUMMARY OF THE INVENTION
  The present invention aims to achieve the above-mentioned purpose except for the portion to be plated.,This is achieved by using a water-decomposable polymer material as a coating material.
  That is, [1] The present invention is a method of partially plating a substrate using a plating catalyst,The substrate is an aggregate substrate in which a large number of substrates are aggregated,Before or after the plating catalyst application step, which is performed by immersing the container containing the substrate in the plating catalyst solution, on the plating construction surface or a portion other than the plating construction surfacePolylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acidThe present invention relates to a method for partially plating a substrate, characterized by providing a step of partially coating with a coating material.Do,Also,
[2] (1)AboveRoughening the surface of the substrate,
  (2) Roughening surfacePolylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acidPartially covering with a covering material,
  (3) A step of applying a plating catalyst to a surface other than the coated surface,
  (4) removing the covering material;
  (5) a step of plating on the catalyst application surface;
Or go through in this order,
[3] (1)AboveThe surface of the substratePolylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acidPartially covering with a covering material,
  (2) a step of roughening the surface other than the coated surface;
  (3) providing a plating catalyst on the roughened surface;
  (4) removing the covering material;
  (5) a step of plating on the catalyst application surface;
Or go through in this order,
[4] (1)AboveRoughening the surface of the substrate,
  (2) providing a plating catalyst;
  (3)Polylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acidPartially covering with a covering material,
  (4) a step of plating a surface other than the coated surface;
  (5) a step of removing the covering material;
In this order, or
[5] (1)AboveRoughening the surface of the substrate,
  (2) providing a plating catalyst;
  (3) plating step,
  (4)Polylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acidPartially covering with a covering material,
  (5) a step of removing the plating material on the surface other than the coated surface;
  (6) a step of removing the covering material;
It is preferable to pass through in this order.
[0006]
  In addition, [2], [3], The plating catalyst application step (3) and the coating material removal step (4) can be performed simultaneously.
  Furthermore, the above [2], [3], A pre-plating step can be added after the step (3) of applying the plating catalyst.
  And above [4], A post-plating step can be provided after the covering material removing step (5).
[0007]
According to the present invention described above, since a water-soluble polymer material or a hydrolyzable polymer material is used as a coating material, the coating material can be removed without using an organic solvent. In addition, the hydrolyzable polymer material can be used by using an alkaline aqueous solution or an acid solution.
If biodegradable materials are used as these polymer materials, they are easily decomposed into water and carbon dioxide by microorganisms in the soil and water, so there is no concern about environmental problems, and disposal after removal from the substrate is possible. It is extremely simple.
[0008]
In addition, water-soluble polymer materials or hydrolyzable polymer materials are more transferable when molded by injection (molded according to the shape of the mold) than plastics, rubber, etc., which are conventionally used as this type of coating material. In addition to its excellent properties, the solidification rate is slow, so the adhesion to the interface with the substrate (generally using a material different from the coating material) is increased, enabling high dimensional accuracy plating and high quality partial plating. Goods can be obtained.
[0009]
Moreover, since this water-soluble polymer material or hydrolyzable polymer material is finally removed from the plated product, the coating shape with these polymer materials is not affected by the shape or dimensions of the final product, It can be designed exclusively for the plating operation and contributes to the reduction of the thickness and thickness of the final product. That is, since the shape and dimensions of the final product are not restricted by the shape and dimensions of the coating material during the plating process, the substrate can be freely coated, thereby forming circuit electrodes in a three-dimensional pattern on the substrate. It is possible to increase the degree of freedom of design of chip parts such as circuit electrodes, and various electronic / electric parts equipped with the chip parts, and to further reduce the size and weight of these electronic / electric parts. Can do.
[0010]
Furthermore, in the present invention, since the catalyst for plating does not remain in the portion where plating is not performed, the insulation resistance value after plating, that is, after circuit formation is increased, and the electrical characteristics of the product can be improved. it can.
[0011]
[Substrate]
As the substrate in the method of the present invention, a substrate composed of an inorganic material such as ceramic or glass in addition to a synthetic resin such as a thermoplastic resin or a thermosetting resin can be used.
Preferably, aromatic liquid crystal polymer, polysulfone, polyether polysulfone, polyarylsulfone, polyetherimide, polyester, acrylonitrile-butadiene-styrene copolymer resin, polyamide, modified polyphenylene oxide resin, norbornene resin, phenol resin, epoxy resin, etc. It is.
More preferably, it is a polyester-based liquid crystal polymer that is close to a metal under temperature conditions with a wide range of heat resistance and thermal expansion coefficient, and has the same stretchability as that of a metal film, and has excellent characteristics equivalent to that of a metal film in a thermal cycle test. It is.
These substrates may be those added with glass fibers, calcium pyrophosphate, wollastonite, calcium carbonate, barium titanate, carbon fibers, quartz fibers, barium sulfate, and the like as fillers.
The substrate may be a flat plate, molded into various shapes (molded product), or a single substrate, or a collective substrate in which a plurality of substrates are highly integrated. Also good.
[0012]
(Coating material)
Moreover, as the covering material, the water-soluble or hydrolyzable polymer material described above can be used, and a material that can be molded into a certain shape on the above-mentioned substrate can be used. In particular, the biodegradable material avoids environmental problems. This is preferable.
Specifically, in addition to polyvinyl alcohol represented by formula 1, modified polyvinyl alcohol represented by formula 2, polylactic acid represented by formula 3, starch, microorganism fermented aliphatic polyester, aliphatic polyester-dicarboxylic acid and diglycol Condensates, aliphatic caprolactone resins, cellulose acetate resins, etc., particularly preferably hydrolyzable polylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acid (random Copolymer, block copolymer).
That is, polylactic acid is (1) hydrolyzable and biodegradable; (2) in the case of water-soluble polymer materials such as polyvinyl alcohol and modified polyvinyl alcohol, to the material generated in the plating catalyst application step In this case, problems such as adsorption of the catalyst and swelling of the material do not occur, so that the plating can be performed with higher accuracy. Since defects such as molecular materials (catalyst adsorption, swelling, etc.) do not occur, the plating catalyst can be applied accurately and reliably. (4) Even if the plating catalyst adheres, the coating material described later This removal step has the advantage that the catalyst is easily removed.
[0013]
[Chemical 1]

[0014]
In addition, the above polylactic acid may be used alone, or it is composed mainly of polylactic acid, and an aliphatic polyester (polyhydroxycarboxylic acid, hydroxycarboxylic acid or aliphatic polyhydric alcohol and aliphatic polyvalent base). Random copolymer comprising two or more monomer components selected from aliphatic polyesters composed of acids, hydroxycarboxylic acids and aliphatic polyhydric alcohols, and two or more monomer components selected from aliphatic polybasic acids Or a block copolymer or a mixture of two or more thereof, a random copolymer or a block copolymer, and an alkali decomposition accelerator, organic and inorganic as necessary. Even if it is a mixture of additives that can be used for general-purpose synthetic resins such as fillers, plasticizers, wetting agents, UV absorbers, antioxidants, lubricants, and colorants There.
The mixing amount or copolymerization amount of the aliphatic polyester is about 1 to 10 wt% with respect to the total amount of the mixture or copolymer, the mixing amount of the alkali decomposition accelerator is about 1 to 100 wt% with respect to the total amount of the mixture, Preferably it is 5-80 wt%, More preferably, it is 10-60 wt%, and about 1-5% is suitable for the mixing amount of another additive with respect to the mixture whole quantity.
[0015]
In addition, the weight average molecular weight of the polylactic acid is preferably about 10,000 to 400,000, and the aliphatic polyester has a weight average molecular weight of about 10,000 to 500,000 when mixed with polylactic acid, preferably 30,000 to About 400,000, more preferably about 50,000 to 300,000 is suitable, and when copolymerizing with polylactic acid, the weight average molecular weight of the copolymer is about 10,000 to 500,000, preferably 30,000 to 40 About 10,000, more preferably about 50,000 to 300,000 is suitable.
Examples of the hydroxycarboxylic acid include glycolic acid, L-lactic acid, D-lactic acid, D / L-lactic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 3-hydroxyvaleric acid, 5- Hydroxyvaleric acid, 6-hydroxycaproic acid and the like can be mentioned, and one or more of these can be used.
Examples of the aliphatic polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, and 3-methyl-1,5-pentane. Diol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, polytetramethylene glycol, 1,4-cyclohexanedimethanol, 1,4-benzenedimethanol, and the like, one or more of these Can be used.
Aliphatic polybasic acids include succinic acid, oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, phenylsuccinic acid, 1, 4-phenylenediacetic acid and the like can be mentioned, and one or more of these can be used.
Examples of the alkali decomposition accelerator include starch, polyvinyl alcohol, polyethylene glycol, polypropylene glycol, polyalkylene glycols such as polyoxytetramethylene glycol, hydrophilic polymer compounds such as polyamino acids, and alkaline hydrolysis such as succinic anhydride and polysuccinimide. Examples include decomposable compounds, and one or more of these can be used. Among these, polyalkylene glycol, particularly polyethylene glycol is preferable from the viewpoint of dispersibility and compatibility with polylactic acid and aliphatic polyester, difficulty in bleeding, and the like.
[0016]
In order to partially coat the substrate with the above-described coating material, there may be mentioned a method of forming a coated shape by various methods such as injection, extrusion, compression, casting, transfer, and the like. In this method, a desired portion of the substrate surface is coated simultaneously with the injection of the coating material by the injection molding method.
[0017]
The coating material is removed using water in the case of a water-soluble polymer material, and using an alkaline aqueous solution or an acid solution (various inorganic acid solutions) in the case of a hydrolyzable polymer material.
In some cases, the coating material can be removed simultaneously with the application of the plating catalyst in the plating catalyst application process described later.
When the coating material is a water-soluble polymer material, although it depends on the type of the polymer material, it is generally preferable to remove it by immersing it in warm water at about 25 to 95 ° C. for 2 to 35 hours.
When the coating material is a hydrolyzable polymer material, especially polylactic acid, it is immersed for about 1 to 120 minutes in a caustic alkali (NaOH, KOH, etc.) aqueous solution having a concentration of about 2 to 15 wt% and a temperature of about 25 to 70 ° C. Is preferably removed. In addition, since the caustic alkaline aqueous solution may drop not only the coating material but also the plating catalyst as the temperature and concentration are high, it is preferable to perform the removing step within this range.
[0018]
[Roughening of substrate surface]
As a method for roughening the surface of the substrate, for example, a known etching method can be applied.
There are wet and dry etching methods, and an appropriate etching method may be employed depending on the type of material used for the substrate.
The dry method can be performed, for example, by irradiating plasma or using gas.
The wet method uses, for example, an aqueous solution of an alkali metal hydroxide such as NaOH or KOH, an aqueous solution of an alkali metal alcoholate such as alcoholic sodium or alcoholic potassium, or an organic solvent such as dimethylformamide. It can be carried out by applying to the surface or by contacting the substrate by immersing the substrate in these liquids.
Among these, the method using an aqueous solution of NaOH, KOH or the like is preferably performed under conditions of a concentration of about 35 to 50 wt% and a temperature of about 70 to 95 ° C.
A method using an aqueous solution of an alkali metal alcoholate or an organic solvent such as dimethylformamide is suitable for roughening after coating with a water-soluble or hydrolyzable polymer material.
In addition, when using an organic solvent, only a base | substrate is swollen and it may not lead to roughening. In this case, an acid or alkali treatment may be performed after the treatment with the organic solvent. Moreover, when roughening is performed after the coating step, it is necessary to set the conditions such that the coating material is not completely removed in the roughening step, but there is no problem even if it is removed to some extent.
[0019]
In the wet method, it is preferable to perform treatment using an acid solution such as hydrochloric acid or hydrofluoric acid after bringing the etching solution into contact with the substrate. This acid treatment is not performed simply to neutralize the alkaline etching solution, but a part of the filler that is contained in the substrate and is present in the vicinity of the surface of the substrate is removed. This is performed to further enhance the surface roughening effect.
Therefore, it is preferable that the conditions for the acid treatment (pH, temperature, time, etc.) are such that the filler is dissolved.
In the wet method, the substrate is placed in a container during the contact between the etching solution and the substrate and the treatment with the acid solution, and the container is immersed in the etching solution or the acid solution. You may carry out by rotating or swinging the container in the liquid. This container can be used in barrels, spheres, box-like bodies, or cage-like bodies with a large number of holes, and the material is surface-treated with a synthetic resin such as polypropylene or a fluorine resin. Metal etc. can be used.
[0020]
[Catalyst for plating]
As the plating catalyst in the present invention (hereinafter sometimes simply referred to as catalyst), known ones can be used, and those containing Pd and Pt are preferred, and these are used as inorganic salts such as chlorides, for example. Is done.
The application of the catalyst for plating is performed by depositing the above catalyst metal by an accelerator treatment after adhering the above inorganic salt to the substrate.
In order to allow the inorganic salt to adhere to the substrate, the inorganic salt solution and the substrate may be brought into contact with each other, for example, by immersing the substrate in an inorganic salt solution or applying this aqueous solution to the substrate. However, in the present invention, as in the roughening step, the container containing the substrate is immersed in an inorganic salt solution, and the container is rotated or swung in the solution. Do it.
The specific conditions differ depending on the substrate material, plating material, plating catalyst material, inorganic salt deposition method, etc., and cannot be determined unconditionally, but use palladium chloride as the plating catalyst salt and immerse it. Taking the case of adopting the law as an example, the following can be cited as an example.
[0021]
Catalyst salt solution composition
PdCl₂・ 2H₂O: 0.1 to 0.3 g / dm³
SnCl₂・ 2H₂O: 10 to 20 g / dm³
HCl: 150-250 cm³/ Dm³
Immersion conditions
Temperature: 20-45 ° C
Time: 1-10 minutes
[0022]
As a solvent for the plating catalyst salt solution, in addition to the above hydrochloric acid, a coating material made of the above water-soluble or hydrolyzable polymer material such as methanol, ethanol, isopropyl alcohol or the like is not completely eluted (one The organic solvent may be used.
[0023]
After adhesion of the plating catalyst salt as described above, it is washed with water and subjected to an accelerator treatment to deposit the plating catalyst (metal) on the substrate.
In general, the accelerator treatment is performed by bringing the accelerator (accelerating liquid) and the base after application of the catalyst salt into contact with each other by dipping or coating. In the present invention, the container containing the base after application of the catalyst salt is used as the accelerator liquid. (In the present invention, all of the above-mentioned plating catalyst salt adhesion, water washing, and accelerator treatment are performed while the substrate is placed in the same container.) .
As this accelerating liquid, an inorganic solution such as sulfuric acid, hydrochloric acid, sodium hydroxide, ammonia or the like is used.
When a catalyst salt solution having the above composition is used and the catalyst salt is applied by immersion under the above conditions, Sn adhered to the substrate surface by washing with water²⁺-Pd²⁺The complex of²⁺Is precipitated as Sn (OH) Cl, and Sn (OH) Cl is dissolved by the subsequent accelerator treatment, so that the complex state has been solved.²⁺As a result, a redox reaction occurs, and metal Pd is generated on the substrate. This metal Pd acts as a plating catalyst.
[0024]
In addition, since the coating material made of a water-soluble or hydrolyzable polymer material may be eluted during the accelerator processing, the coating material may be removed simultaneously with the accelerator processing, or the coating material may be removed. After that, the accelerator process may be performed.
Of course, the accelerator process can be terminated before the covering material is completely eluted.
[0025]
When the thickness of the coating material made of a water-soluble or hydrolyzable polymer material is as thin as about 10 to 1000 μm, preferably about 10 to 500 μm, the above-described plating catalyst salt adheres (for example, the Sn²⁺-Pd²⁺Complex attachment), washing with water (precipitation of Sn (OH) Cl by hydrolysis of the complex), accelerator treatment (Sd (OH) Cl is dissolved, and the complex state is released during washing with water.²⁺In the process of applying a plating catalyst consisting of a series of operations of producing a metal Pd by oxidation-reduction reaction with the catalyst, the coating material may be completely eluted, and simultaneously with the application of the plating catalyst, the coating material is removed. It can be carried out.
In this case, the accelerator treatment is preferably performed at a temperature of the accelerator of about 40 to 80 ° C. and a contact time with the accelerator of about 30 to 120 minutes.
In addition, in the case where the coating material is provided by the injection molding method in which the base is a part of the mold after the roughening of the base, if the base and the mold are brought into close contact, the unevenness (rough surface) provided on the base ) Disappears, so a small gap is formed between the base and the mold to form an injection mold, and the coating material is also applied to this minute gap (a part that does not require a coating material). May be formed (that is, a burr is formed). Since the coating material (burr) of the minute gaps is extremely thin, the coating material can be completely eluted during the above-described plating catalyst application step.
As described above, the simultaneous application of the plating catalyst application step and the coating material removal step is not only effective in terms of the process surface, but also protects the roughened surface of the substrate, and in addition, highly accurate plating. The effect of construction can also be obtained.
[0026]
〔plating〕
As the plating method in the present invention, a known metalizing method (electroless plating method or electroplating method) can be employed.
Examples of the plating metal include copper, tin, lead, nickel, gold, and other various metals.
The plating process can be performed in multiple times or can be performed once at a time.
In addition, a preliminary plating process can also be provided after a catalyst provision process. Pre-plating can also be performed by a known metalizing method, preferably an electroless plating method, and a plating metal similar to the metal in the so-called main plating process can be used. By providing this preliminary plating step, the plating quality in the main plating step can be further improved.
Further, a post plating step can be provided. The post-plating step can also be performed by a known metalizing method, preferably an electroless plating method, and the plating metal may be the same type as the metal in the main plating step, but is different. Also good.
[0027]
[Removal of plating material]
The plating material can be removed by any method as long as it can remove the plating metal as described above. In general, a solution of an inorganic salt such as ferric chloride or cupric chloride is used. In the present invention, as in the roughening step and the plating catalyst application step, the container as described above is filled with the base after plating. It is preferable to immerse the substrate in an inorganic salt solution and rotate or swing it.
[Annealing treatment]
In the present invention, after each of the above steps is completed, annealing treatment can be performed.
By this annealing treatment, the adhesion of the plating film can be further improved.
The annealing process is preferably performed at 160 to 175 ° C. and held for 1 to 5 hours, and then gradually cooled to room temperature.
[0028]
【Example】
Example 1
[Substrate molding process]
1A (perspective view), (B) ((A) of FIG. 1 (A) using an aromatic polyester (liquid crystal polymer << using the product name "Vectra C810" manufactured by Celanese USA) >>). A substrate (single product) 1 having a shape shown in a partially cutaway view was formed.
The base body 1 has an outer dimension of 50 × 30 × 5 (mm), and has two through holes (Through Holes) 2 and 2 at diagonal positions on the top surface as shown in the figure. Yes.
A plurality of the substrates 1 are put into a polypropylene barrel container having a large number of holes, and a degreasing solution heated to 60 ° C. while rotating the container (trade name “A Screen A220” manufactured by Okuno Pharmaceutical Co., Ltd.) 50 g / Liquid (hereinafter referred to as an aqueous solution of liters as L and milliliters as mL) for 10 minutes, washed with water and degreased.
[0029]
[Roughening process of substrate surface]
An alkaline solution in which 350 to 500 g of metal Na (430 g in this example) is dissolved in 1 L of methyl alcohol is heated to 90 ° C., and a plurality of the degreased substrates 1 are put in the barrel-shaped container in the heated solution. The surface of the substrate 1 was roughened by being kept immersed for 30 to 80 minutes (40 minutes in this example) while being rotated.
In addition, when using ethyl alcohol (metal Na430g) instead of methyl alcohol, roughening was possible under the same conditions.
When isopropyl alcohol (metal Na 430 g) is used instead of methyl alcohol, the alkaline solution is heated to 60 ° C., and a plurality of the degreased substrates 1 are put in the barrel-shaped container in the solution. And then kept for 10 minutes while rotating and then mixed with chromic acid (CrO₃A mixture solution of 22 wt% and concentrated sulfuric acid 54 wt%) was heated to 60 ° C., and was put in a barrel-shaped container while being rotated while being roughened.
Further, when an alkaline solution in which 350 to 500 g of NaOH (400 g in this example) was dissolved in 1 L of water was used, roughening could be performed under the same conditions as in the case of using the above methyl alcohol.
[0030]
[Substrate coating step]
As a covering material 3 heated to 150 to 260 ° C. (190 ° C. in this example) in a secondary mold in which the substrate 1 after surface roughening is set and held at 5 to 30 ° C. (10 ° C. in this example) Water-soluble polymer material (polyvinyl alcohol (hereinafter referred to as “PVA”) “using Kuraray's trade name“ Poval ”)), injection pressure of 200 to 1200 kg / cm²(In this example, 350 kg / cm²) To obtain a partially coated 3 molded article having the form shown in FIG. 2 (perspective view).
The thickness of the covering material 3 of this molded product was 1 mm and 0.5 mm.
[0031]
[Plating catalyst application step and coating material removal step]
To methyl alcohol, a mixed hydrochloric acid solution of stannous chloride and palladium chloride as a catalyst salt for plating (trade name “Enylex CT-8” manufactured by Sugawara Eugleite Co., Ltd.) was added at a rate of 20 mL / L. The solution was kept at 0 ° C., and a plurality of the above partially coated molded products were placed in the same barrel-shaped container as described above and immersed in this solution while rotating for 3 to 5 minutes (4 minutes in this example). Then, it was washed with water and immersed in hydrochloric acid (50 mL / L) heated to 60 ° C. for 60 minutes (accelerator treatment) to apply a plating catalyst to the portion other than the coating material 3 of the partially coated molded article, and to cover the coating material. 3 was removed by dissolution.
In both cases where the thickness of the covering material 3 was 1 mm and 0.5 mm, the application of the catalyst for plating and the removal of the covering material 3 were simultaneously performed satisfactorily.
[0032]
[Plating process]
While the plurality of substrates 1 after the removal of the covering material 3 are placed in the barrel-shaped container, the substrates 1 are immersed in a copper plating bath having the composition shown in Table 1 and rotated under the plating conditions shown in Table 2. After performing electroless copper plating to a thickness of 0.3 to 20.0 μm (10 μm in this example), an annealing treatment is performed by holding at 170 ° C. for 1 hour and gradually cooling to room temperature. The thing of the aspect shown in 3 was obtained.
Also, after electroless copper plating is applied to a thickness of 0.5 μm, the copper electroplating is applied to a thickness of 0.5 μm while being placed in the barrel-shaped container, and then the same annealing treatment as described above. In the case of performing the same process, a similar embodiment was obtained.
In FIG. 3, the portion indicated by reference numeral 4 is a portion plated with copper, and as shown in FIG. 3, this copper plating 4 is provided only on the plating catalyst application surface, that is, the coating material shown in FIG. 3 was applied to the portion other than the portion covered with 3 and the surface in the through hole 2.
[0033]
[Table 1]
Copper plating bath composition
CuSO₄・ 5H₂O: 0.04 mol / L
HCHO: 0.1 mol / L
NaOH: 0.2 mol / L
EDTA · 4Na: 0.08 mol / L
α, α'-dipyridyl: 5 to 10 ppm
PEG-1000^{* 1}    : 50-100ppm
* 1 PEG-1000: Stabilizer (trade name, manufactured by Ebara Eugene Corporation)
[0034]
[Table 2]
Plating conditions
Bath temperature: 60-70 ° C
Air agitation: 0.1 L / L · min
Bath: 0-1dm²/ L
[0035]
Comparative Example 1
[Substrate molding process]
In the same manner as in Example 1, a substrate (single product) 11 having the shape shown in FIG. Reference numeral 12 denotes a through hole, and 11 ′ denotes a concave portion of the substrate 11.
[0036]
[Roughening process of substrate surface]
The substrate 11 was roughened in the same manner as in Example 1.
[0037]
[Plating catalyst application process]
In the concentrated sulfuric acid having a concentration of 150 mL / L, the same product name “Enilex CT-8” manufactured by Ebara Eugelite Co., Ltd. as in Example 1 was mixed as a catalyst salt for plating at a rate of 20 mL / L and kept at 30 ° C. In the solution, the surface-roughened primary molded article 11 was dipped for 3 minutes in the same manner as in Example 1 and then washed with water, and the accelerator liquid composed of sulfuric acid having a concentration of 80 mL / L was maintained at 50 ° C. It was immersed in this solution for 4 minutes, washed with water, and a plating catalyst was applied to the entire surface of the substrate 11.
[0038]
[Substrate coating step]
The base 11 after the plating catalyst is applied is set in the secondary mold, and the partially coated molded product of the embodiment shown in FIG. 5 (with the same resin as the base 11 in the recess 11 ′ in FIG. 4) by the same resin as the base 11. What was obtained by molding the covering material 13) was obtained.
[0039]
[Plating process]
The partially coated molded article was subjected to electroless copper plating in the same manner as in Example 1.
Since this copper plating has poor adhesion between the substrate 11 and the covering material 13, it can be visually recognized that the copper plating is also applied to the portion where the plating catalyst application surface of the interface is viewed.
[0040]
Example 2
[Substrate molding process]
In the same manner as in Example 1, the same substrate 1 as in Example 1 was molded.
[0041]
[Roughening process of substrate surface]
The substrate 1 was roughened in the same manner as in Example 1.
[0042]
[Substrate coating step]
As a covering material 3 heated to 150 to 260 ° C. (190 ° C. in this example) in a secondary mold in which the substrate 1 after surface roughening is set and held at 5 to 30 ° C. (10 ° C. in this example) Hydrolyzable polymer material (polylactic acid resin (using trade name “LACEA” manufactured by Mitsui Chemicals, Inc.)), injection pressure 200 to 1200 kg / cm²(In this example, 350 kg / cm²) To obtain a partially coated 3 molded article having the form shown in FIG. 2 (perspective view). The thickness of the covering material 3 of this molded product was 1.5 mm.
[0043]
[Plating catalyst application process]
As a catalyst salt for plating, the same product name “Enylex CT-8” manufactured by Ebara Eugilite as in Example 1 was added at a rate of 20 mL / L, and HCl was further added at a rate of 150 mL / L. Was kept at 30 ° C., and the partially coated molded article was immersed in this solution in the same manner as in Example 1, for 3 to 5 minutes (4 minutes in this example), and then washed with water to 30 ° C. It was immersed (accelerator treatment) in warmed hydrochloric acid (5 to 10%, 8% in this example) for 4 minutes, and a catalyst for plating was applied to portions other than the coating material 3 of the partially coated molded article.
[0044]
[Coating material removal process]
The substrate 1 after the plating catalyst was applied was immersed in an aqueous NaOH solution at a concentration of 7 wt% and 30 ° C. for 40 minutes in the same manner as in Example 1 to remove the coating material 3.
[0045]
In addition, when the thickness of the coating material 3 made of polylactic acid is 1 mm, which is the same as that of Example 1, and 0.5 mm, in any case, in the plating catalyst application step, the plating catalyst is applied at the same time. The covering material 3 could be removed.
[0046]
[Plating process]
The partially coated molded article was subjected to electroless copper plating in the same manner as in Example 1.
Further, in the same manner as in Example 1, after electroless copper plating, electrolytic copper plating was performed.
In any case, as in Example 1, only the plating catalyst application surface, that is, the portion other than the portion covered with the coating material 3 shown in FIG. Was given.
[0047]
Example 3
[Substrate molding process]
In the same manner as in Example 1, the same substrate 1 as in Example 1 was molded.
[0048]
[Substrate coating step]
The substrate 1 was set, and a hydrolyzable resin was injected in the same manner as in Example 2 to obtain a partially coated molded product similar to that in Example 1.
[0049]
[Roughening process of substrate surface]
In the same manner as in Example 1, the above partially coated molded article was added to a dimethylformamide solution having a concentration of 60 to 80% (50% in this example) heated to 35 to 60 ° C (50 ° C in this example). After immersing for 5 to 120 minutes (60 minutes in this example) to swell the portion other than the covering material 3, that is, the surface of the substrate 1, it was washed with water and then heated to 70 to 75 ° C (70 ° C in this example). Concentrated sulfuric acid (600cm³/ Dm³89% phosphoric acid (100cm³/ Dm³) · Chromic acid (30 g / dm³) For 30 to 120 minutes (70 minutes in this example) to roughen the swollen portion.
[0050]
[Plating catalyst application process]
A solution obtained by adding palladium chloride (made by Okuno Pharmaceutical Co., Ltd.) as a plating catalyst salt to ethyl alcohol at a rate of 30 mL / L was heated to 50 to 90 ° C. (60 ° C. in this example). In the same manner as in Example 1, the surface-roughened molded article was immersed for 15 to 100 minutes (60 minutes in this example), then washed with water, and other than the above-mentioned surface roughened portion, that is, the covering material 3. A plating catalyst was applied to the part.
[0051]
[Coating material removal process]
In the same manner as in Example 1, the molded product after applying the catalyst was placed in a 20 to 80 ° C. (50 ° C. in this example) 5 to 20% (5% in this example) caustic soda solution for 40 to 80 minutes (in this example). 60 minutes), and the covering material 3 was hydrolyzed and removed.
[0052]
[Plating process]
In the same manner as in Example 1, electroless copper plating 4 was applied.
The copper plating 4 was applied to the portion other than the portion covered with the covering material 3 and the surface in the through hole 2 as in the case of Example 1.
[0053]
Example 4
[Substrate molding process]
In the same manner as in Example 1, the same substrate 1 as in Example 1 was molded.
[0054]
[Roughening process of substrate surface]
In the same manner as in Example 1, the entire surface of the substrate 1 was roughened.
[0055]
[Plating catalyst application process]
In the same manner as in Example 1, a plating catalyst was applied to the entire surface of the substrate 1.
[0056]
[Plating process]
An electroless copper plating with a thickness of 5 μm was applied in the same manner as in Example 1 except that the annealing treatment was not performed.
[0057]
[Coating process]
Using the same hydrolyzable resin as used in Example 2, the substrate after plating was subjected to partial coating (coating on the portion where plating was left) in the same manner as in Example 1.
[0058]
[Plating material removal process]
The part which is not coated by immersing the molded product after the coating process in a ferric chloride or cupric chloride (28 to 42 wt% << 40 wt% in this example >>) solution in the same manner as in Example 1. The plating material was removed.
[0059]
[Coating material removal process]
After the coating material was hydrolyzed and removed in the same manner as in Example 2, the same annealing treatment as in Example 1 was performed.
[0060]
Example 5
[Substrate molding process]
In the same manner as in Example 1, the same substrate 1 as in Example 1 was molded.
[0061]
[Roughening process of substrate surface]
In the same manner as in Example 1, the entire surface of the substrate 1 was roughened.
[0062]
[Plating catalyst application process]
In the same manner as in Example 1, a plating catalyst was applied to the entire surface of the substrate 1.
[0063]
[Substrate coating step]
Using the same hydrolyzable resin as used in Example 2, a partially coated molded article similar to Example 1 was obtained in the same manner as in Example 1.
[0064]
[Plating process]
Electroless copper plating with a thickness of 1 to 5 μm was performed in the same manner as in Example 1 except that the annealing treatment was not performed.
[0065]
[Coating material removal process]
In the same manner as in Example 1, it was immersed in a 4 to 25% caustic soda solution at 60 to 90 ° C. for 1 to 3 hours to hydrolyze and remove the coating material.
[0066]
[Post-plating process]
In the same manner as in Example 1, electroless copper plating with a thickness of 1 to 20 μm was again applied to the entire surface of the molded article on which electroless copper plating was applied.
[0067]
Example 6
Except for using PVA as a coating material and treating the plating with aluminum chloride and lithium aluminum hydroxide in a tetrahydrofuran solution to obtain an aluminum plating with a thickness of 0.5 to 2.5 μm (in this example 2 μm), Example 4 was repeated.
[0068]
Example 7
[Substrate molding process]
A base (aggregate base) 21 having the shape shown in FIG. 6 (perspective view) is molded from an aromatic polyester (liquid crystal polymer << using the trade name “Vectra C810” manufactured by Celanese, USA>) using a primary mold. did.
The external dimensions of the substrate 21 are a≈40 mm, b≈5 mm, c≈4 mm, d≈7 mm, and e≈2 mm. As shown in the figure, a plurality of through holes are formed on the top surface in two straight lines. It has holes (Through Hole) 2, 2,.
A plurality of aggregate substrates 21 are placed in a polypropylene barrel-shaped container having a large number of holes, and a degreasing solution heated to 60 ° C. while rotating the container (trade name “A Screen A220” manufactured by Okuno Pharmaceutical Co., Ltd.). (50 g / L aqueous solution) for 10 minutes, washed with water and degreased.
[0069]
[Roughening process of substrate surface]
An alkaline solution in which 430 g of metal Na is dissolved in 1 L of methyl alcohol is heated to 90 ° C., and a plurality of the degreased substrates 21 are immersed in the heated barrel solution while rotating in the barrel-shaped container. The surface of the substrate 21 was roughened by holding for 40 minutes.
In addition, when using ethyl alcohol (metal Na430g) instead of methyl alcohol, roughening was possible under the same conditions.
When isopropyl alcohol (metal Na 430 g) is used instead of methyl alcohol, the alkaline solution is heated to 60 ° C., and a plurality of the degreased substrates 21 are placed in the barrel-shaped container. And then kept for 10 minutes while rotating and then mixed with chromic acid (CrO₃A mixture solution of 22 wt% and concentrated sulfuric acid 54 wt%) was heated to 60 ° C., and was put in a barrel-shaped container while being rotated while being roughened.
Furthermore, when an alkaline solution in which 400 g of NaOH was dissolved in 1 L of water was used, roughening could be performed under the same conditions as in the case of using the above methyl alcohol.
[0070]
[Substrate coating step]
A hydrolyzable polymer material (polylactic acid resin << trade name of Mitsui Chemicals, Inc.} as a coating material 3 heated to 190 ° C is placed in a secondary mold in which the substrate 21 after surface roughening is set and held at 10 ° C. LACEA "" >>), injection pressure 350 kg / cm²7 (A) (overall perspective view), (B) (an explanatory view of the α-α line cutting portion in FIG. 7 (A)), (C) (partially cutaway view of FIG. 7 (B)) The partially coated 3 molded product (collected molded product) having the form shown in FIG. The thickness of the covering material 3 of this molded product was 1 mm and 0.5 mm.
[0071]
[Plating catalyst application step and coating material removal step]
To methyl alcohol, a mixed hydrochloric acid solution of stannous chloride and palladium chloride as a catalyst salt for plating (trade name “Enylex CT-8” manufactured by Sugawara Eugleite Co., Ltd.) was added at a rate of 20 mL / L. In this solution, a plurality of the above partially coated molded products are placed in a barrel-like container similar to the above, immersed in the container while rotating for 4 minutes, washed with water, and heated to 60 ° C. It was immersed in warm hydrochloric acid (50 mL / L) for 60 minutes (accelerator treatment), and a catalyst for plating was applied to portions other than the coating material 3 of the partially coated molded article, and the coating material 3 was dissolved and removed.
In both cases where the thickness of the covering material 3 was 1 mm and 0.5 mm, the application of the catalyst for plating and the removal of the covering material 3 were simultaneously performed satisfactorily.
[0072]
[Plating process]
While the plurality of substrates 21 after the removal of the covering material 3 are placed in the barrel-shaped container, the substrates 21 are immersed in a pre-plating bath having the composition shown in Table 3 and rotated under the plating conditions shown in the same table. After applying electroless copper plating to a thickness of 0.5 to 1.5 μm (1 μm in this example), it is immersed in a main plating bath having the composition shown in Table 4 and rotated. Under the plating conditions shown, electroless copper plating was performed on the preliminary plating so as to have a thickness of 9.5 to 8.5 μm (9 μm in this example), so that the total plating thickness was 10 μm.
In addition, after this copper plating, post-plating such as electroless Ni plating / electroless Au plating, or electric Ni plating / electrical Au plating can be performed, and the same annealing treatment as in the first embodiment is performed as a final process. You can also.
The cross-sectional view of FIG. 8 schematically shows a portion plated in this example. In FIG. 8, the portion indicated by reference numeral 4 is a portion plated with copper (or post-plating such as Ni plating / Au plating after copper plating). As shown in FIG. 8, this plating 4 is used for plating. Only the catalyst application surface, that is, the portion other than the portion covered with the coating material 3 shown in FIGS. 7A to 7C and the surface in the through hole 2 were applied.
[0073]
[Table 3]
Preliminary (copper) plating bath composition and conditions
CuSO₄・ 5H₂O: 0.04 mol / L
HCHO (37% solution): 0.3 mol / L
NaOH: pH 12.2
EDTA · 4Na: 0.10 mol / L
Stabilizer^{* 1}            :Slightly
Bath temperature: 35 ° C
* 1 Stabilizer: Metal (metal ion) system
[0074]
[Table 4]
This (copper) plating bath composition and conditions
CuSO₄・ 5H₂O: 0.04 mol / L
HCHO (37% solution): 0.06 mol / L
NaOH: pH 12
EDTA · 4Na: 0.1 mol / L
Stabilizer^{* 1}            :Slightly
Bath temperature: 65 ° C
Plating speed: 2.5 μm / hr
[0075]
Then, it cut along the virtual line shown with a dotted line in FIG. 6, and obtained the chip component of the shape shown in FIG. 9 (perspective view).
[0076]
Example 8
The aggregate substrate 21 of Example 7 was used and coated in the manner shown in FIGS. 7A to 7C, and the pre-plating bath composition / conditions shown in Table 3 of Example 7 and the present plating bath composition / Except for the conditions, plating was performed in the same manner as in Example 3, and then cut in the same manner as in Example 7 to obtain a chip component having the shape shown in FIG. 9 (perspective view).
[0077]
Example 9
The aggregate substrate 21 of Example 7 was used and coated in the manner shown in FIGS. 7A to 7C, and the pre-plating bath composition / conditions shown in Table 3 of Example 7 and the present plating bath composition / Except for the conditions, plating was performed in the same manner as in Example 4, and then cut in the same manner as in Example 7 to obtain a chip component having the shape shown in FIG. 9 (perspective view).
[0078]
Example 10
The aggregate substrate 21 of Example 7 was used and coated in the manner shown in FIGS. 7A to 7C, and the pre-plating bath composition / conditions shown in Table 3 of Example 7 and the present plating bath composition / Except for the conditions, plating was performed in the same manner as in Example 5, and then cut in the same manner as in Example 7 to obtain a chip component having the shape shown in FIG. 9 (perspective view).
[0079]
Example 11
Except for using PVA as a coating material and treating the plating with aluminum chloride and lithium aluminum hydroxide in a tetrahydrofuran solution to obtain an aluminum plating with a thickness of 0.5 to 2.5 μm (in this example 2 μm), Example 9 was repeated.
[0080]
【The invention's effect】
According to the present invention, the conventional resist coating / curing / removing step can be omitted, and therefore there is no concern about environmental problems due to the organic solvent, and the step can be shortened.
In addition, it is possible to provide high-quality electronic / electrical parts with high dimensional accuracy and high electrical conductivity.
[Brief description of the drawings]
1A and 1B are diagrams showing an example of the shape of a base used in an embodiment of the present invention, in which FIG. 1A is a perspective view and FIG. 1B is a partially cutaway view of FIG.
FIG. 2 is a perspective view showing an example of a state in which a covering material is applied to the base body of FIG.
FIG. 3 is a perspective view showing an example of a state in which electroless plating is applied to that of FIG.
FIG. 4 is a view showing an example of a substrate used in a comparative example of the present invention.
5 is a perspective view showing an example of a state in which a covering material is applied to the base body of FIG. 4;
FIG. 6 is a perspective view showing an example of the shape of a collective substrate used in another embodiment of the present invention.
7 is a view showing an example of a state in which a covering material is applied to the aggregate base body of FIG. 6; FIG. (C) is a partially cutaway view of (B).
8 is a partial cross-sectional view showing a state in which the aggregate base body of FIG. 6 is plated when the covering material of FIG. 7 is applied.
9 is a perspective view showing a state in which the collective plating product plated in the state of FIG. 8 is cut into each chip part. FIG.
[Explanation of symbols]
1,11,21 substrate
2,12 holes
3,13 Coating material
4 plating

Claims (6)

A method for partially plating the substrate using the plating catalyst, the substrate is a collection substrate were assembled many substrates, performed by immersing the vessel containing the substrate to the catalyst solution for plating Before or after the plating catalyst application step, partially coated with polylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acid on the plating surface or a portion other than the plating surface A method of partially plating a substrate, comprising the step of coating the substrate. (1) a step of roughening the surface of the substrate,
(2) A step of partially covering the roughened surface with a coating material which is polylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acid ,
(3) A step of applying a plating catalyst to a surface other than the coated surface,
(4) removing the covering material;
(5) a step of plating on the catalyst application surface;
The base partial plating method according to claim 1, wherein passing through in this order. (1) Surface polylactic acid of the substrate or, the step of partially coated with a mixture or copolymer of an aliphatic polyester composed mainly of polylactic acid coating material,
(2) a step of roughening the surface other than the coated surface;
(3) providing a plating catalyst on the roughened surface;
(4) removing the covering material;
(5) a step of plating on the catalyst application surface;
The base partial plating method according to claim 1, wherein passing through in this order. 4. The method for partially plating a substrate according to claim 2, wherein the step of applying a catalyst for plating and the step of removing the coating material are performed simultaneously. (1) a step of roughening the surface of the substrate,
(2) providing a plating catalyst;
(3) A step of partially coating with a coating material which is polylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acid ,
(4) a step of plating a surface other than the coated surface;
(5) a step of removing the covering material;
The base partial plating method according to claim 1, wherein passing through in this order. (1) a step of roughening the surface of the substrate,
(2) providing a plating catalyst;
(3) plating step,
(4) A step of partially coating with a coating material which is polylactic acid or a mixture or copolymer with an aliphatic polyester mainly composed of polylactic acid ,
(5) a step of removing the plating material on the surface other than the coated surface;
(6) a step of removing the covering material;
The base partial plating method according to claim 1, wherein passing through in this order.

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