JP2004259999A - Manufacturing method of circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the manufacturing method of a circuit board capable of protecting the through-holes so as not to be affected by the work-processing at the work-processing and easily releasing the protection of the through-holes after the work-processing in the circuit board having through holes which should not be processed. <P>SOLUTION: A board 1 on which conductor films 2, 3 are formed as at least one electrode is prepared, through-holes 5, 6 are formed to the insulating board 1, and a thermally vanishing materials are filled in the through-holes 5, 6. Further, the insulating board 1 is work-processed under a temperature environment wherein the temperature is lower than a temperature at which the thermally vanishing materials are vanished, the board 1 subjected to work-processing is heated to a temperature or over at which the thermally vanishing materials 7, 8 are vanished, and the through-holes 5, 6 are exposed by vanishing the thermally vanishing materials 7, 8. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００３４】
式（１）中、ｍは２〜５の整数を表し、Ｙ^（ｍ）は周期表のＩＶＢ族、ＶＢ族又はＶＩＢ族の原子を表し、Ｚは水素基、炭化水素基、メルカプト基、アミノ基、ハロゲン基、アルコキシル基、アルキルチオ基、カルボニルオキシ基又はオキソ基を表す。
【００３５】
上記式（１）で表される官能基を有する光反応触媒は、一般式（１）で表される官能基のうち、異なるものを複数種有していてもよい。
上記一般式（１）で表される官能基を有する光反応触媒としては、例えば、酸素、硫黄、窒素、リン及び炭素からなる群より選択されるＹ^（ｍ）で示される原子に対し、カルボニル基が２個結合した化合物であって、Ｙ^（ｍ）で示される原子の価数に応じて適宜、Ｚで示される炭化水素基又はオキシド基を有するもの等が挙げられる。
【００３６】
上記炭化水素基としては、例えば、脂肪族系炭化水素基、不飽和脂肪族系炭化水素基、芳香族系炭化水素基等が挙げられる。これらの炭化水素基は、本発明の目的を阻害しない範囲でアミノ基、水酸基、エーテル基、エポキシ基、重合性不飽和基、ウレタン基、ウレア基、イミド基、エステル基等の置換基を有していても良い。また、異なる炭化水素基を組み合わせて用いてもよい。
【００３７】
上記式（１）で表される官能基を有する光反応触媒は、環状化合物であってもよい。このような環状化合物としては、例えば、環状鎖の中に１個又は２個以上の同種又は異種の上記一般式（１）で表される官能基を有する化合物等が挙げられる。更に、複数個の同種又は異種の上記環状化合物を適当な有機基で結合した化合物や、複数個の同種又は異種の上記環状化合物をユニットとして少なくとも１個以上含む双環化合物等も用いることができる。
【００３８】
上記式（１）で表される官能基を有する光反応触媒としては、Ｙ^（ｍ）で表される原子が酸素原子の場合には、例えば、酢酸無水物、プロピオン酸無水物、ブチル酸無水物、イソブチル酸無水物、バレリック酸無水物、２−メチルブチル酸無水物、トリメチル酢酸無水物、ヘキサン酸無水物、ヘプタン酸無水物、デカン酸無水物、ラウリル酸無水物、ミリスチリル酸無水物、パルミチン酸無水物、ステアリル酸無水物、ドコサン酸無水物、クロトン酸無水物、アクリル酸無水物、メタクリル酸無水物、オレイン酸無水物、リノレイン酸無水物、クロロ酢酸無水物、ヨード酢酸無水物、ジクロロ酢酸無水物、トリフルオロ酢酸無水物、クロロジフルオロ酢酸無水物、トリクロロ酢酸無水物、ペンタフルオロプロピオン酸無水物、ヘプタフルオロブチル酸無水物、コハク酸無水物、メチルコハク酸無水物、２，２−ジメチルコハク酸無水物、イソブチルコハク酸無水物、１，２−シクロヘキサンジカルボン酸無水物、ヘキサヒドロ−４−メチルフタル酸無水物、イタコン酸無水物、１，２，３，６−テトラヒドロフタル酸無水物、３，４，５，６−テトラヒドロフタル酸無水物、マレイン酸無水物、２−メチルマレイン酸無水物、２，３−ジメチルマレイン酸無水物、１−シクロペンテン−１，２−ジカルボン酸無水物、グルタル酸無水物、１−ナフチル酢酸無水物、安息香酸無水物、フェニルコハク酸無水物、フェニルマレイン酸無水物、２，３−ジフェニルマレイン酸無水物、フタル酸無水物、４−メチルフタル酸無水物、３，３’，４，４’−ベンゾフェノンテトラカルボン酸ジ無水物、４，４’−（ヘキサフルオロプロピリデン）ジフタル酸無水物、１，２，４，５−ベンゼンテトラカルボン酸無水物、１，８−ナフタレンジカルボン酸無水物、１，４，５，８−ナフタレンテトラカルボン酸無水物等；マレイン酸無水物とラジカル重合性二重結合を持つ化合物の共重合体として、例えば、マレイン酸無水物と（メタ）アクリレートの共重合体、マレイン酸無水物とスチレンの共重合体、マレイン酸無水物とビニルエーテルの共重合体等が挙げられる。これらのうち市販品としては、例えば、旭電化社製のアデカハードナーＥＨ−７００、アデカハードナーＥＨ−７０３、アデカハードナーＥＨ−７０５Ａ；新日本理化社製のリカシッドＴＨ、リカシッドＨＴ−１、リカシッドＨＨ、リカシッドＭＨ−７００、リカシッドＭＨ−７００Ｈ、リカシッドＭＨ、リカシッドＳＨ、リカレジンＴＭＥＧ；日立化成社製のＨＮ−５０００、ＨＮ−２０００；油化シェルエポキシ社製のエピキュア１３４Ａ、エピキュアＹＨ３０６、エピキュアＹＨ３０７、エピキュアＹＨ３０８Ｈ；住友化学社製のスミキュアーＭＳ等が挙げられる。
【００３９】
上記式（１）で表される官能基を有する光反応触媒としては、Ｙ^（ｍ）で表される原子が窒素原子の場合には、例えば、コハク酸イミド、Ｎ−メチルコハク酸イミド、α，α−ジメチル−β−メチルコハク酸イミド、α−メチル−α−プロピルコハク酸イミド、マレイミド、Ｎ−メチルマレイミド、Ｎ−エチルマレイミド、Ｎ−プロピルマレイミド、Ｎ−ｔｅｒｔ−ブチルマレイミド、Ｎ−ラウリルマレイミド、Ｎ−シクロヘキシルマレイミド、Ｎ−フェニルマレイミド、Ｎ−（２−クロロフェニル）マレイミド、Ｎ−ベンジルマレイミド、Ｎ−（１−ピレニル）マレイミド、３−メチル−Ｎ−フェニルマレイミド、Ｎ，Ｎ’−１，２−フェニレンジマレイミド、Ｎ，Ｎ’−１，３−フェニレンジマレイミド、Ｎ，Ｎ’−１，４−フェニレンジマレイミド、Ｎ，Ｎ’−（４−メチル−１，３−フェニレン）ビスマレイミド、１，１’−（メチレンジ−１，４−フェニレン）ビスマレイミド、フタルイミド、Ｎ−メチルフタルイミド、Ｎ−エチルフタルイミド、Ｎ−プロピルフタルイミド、Ｎ−フェニルフタルイミド、Ｎ−ベンジルフタルイミド、ピロメリット酸ジイミド等が挙げられる。
【００４０】
上記式（１）で表される官能基を有する光反応触媒としては、Ｙ^（ｍ）で表される原子がリン原子の場合には、例えば、ビス（２，６−ジメトキシベンゾイル）−２，４，４−トリメチル−ペンチルフォスフィンオキサイド、ビス（２，４，６−トリメチルベンゾイル）−フェニルフォスフィンオキシド等が挙げられる。
【００４１】
上記式（１）で表される官能基を有する光反応触媒としては、Ｙ^（ｍ）で表される原子が炭素原子の場合には、例えば、２，４−ペンタンジオン、３−メチル−２，４−ペンタンジオン、３−エチル−２，４−ペンタンジオン、３−クロロ−２，４−ペンタンジオン、１，１，１−トリフルオロ−２，４−ペンタンジオン、１，１，１，５，５，５−ヘキサフルオロ−２，４−ペンタンジオン、２，２，６，６−テトラメチル−３，５−ヘプタンジオン、１−ベンゾイルアセトン、ジベンゾイルメタン等のジケトン類；ジメチルマロネート、ジエチルマロネート、ジメチルメチルマロネート、テトラエチル１，１，２，２−エタンテトラカルボン酸等のポリカルボン酸エステル類；メチルアセチルアセトナート、エチルアセチルアセトナート、メチルプロピオニルアセテート等のα−カルボニル−酢酸エステル類等が挙げられる。なかでも、消滅後の残さが極めて少ないことから、ジアシルフォスフィンオキシド及びその誘導体が好適である。
【００４２】
上記式（１）で表される官能基を有する光反応触媒の配合量の好ましい下限は、架橋性シリル基を有するポリオキシアルキレン樹脂１００重量部に対して０．０１重量部、好ましい上限は３０重量部である。０．０１重量部未満であると、光反応性を示さなくなることがあり、３０重量部を超えると、ポリオキシアルキレン樹脂組成物の光透過性が低下して、光を照射しても表面のみが架橋、硬化し、深部は架橋、硬化しないことがある。より好ましい下限は０．１重量部、より好ましい下限は２０重量部である。
【００４３】
上記ポリオキシアルキレン樹脂組成物は、増感剤を含有してもよい。増感剤を含有することにより、光反応性が向上し、光の照射時間を短くしたり、光の照射エネルギーを低くしたり、表面から深部まで均一に架橋、硬化させたりすることができる。
【００４４】
上記増感剤としては、例えば、４−（２−ヒドロキシエトキシ）フェニル（２−ヒドロキシ−２−プロピル）ケトン、α−ヒドロキシ−α，α’−ジメチルアセトフェノン、メトキシアセトフェノン、２，２−ジメトキシ−２−フェニルアセトフェノン等のアセトフェノン誘導体化合物；ベンゾインエチルエーテル、ベンゾインプロピルエーテル等のベンゾインエーテル系化合物；ベンジルジメチルケタール等のケタール誘導体化合物；ハロゲン化ケトン；アシルフォスフィンオキシド；アシルフォスフォナート；２−メチル−１−［４−（メチルチオ）フェニル］−２−モルフォリノ プロパン−１−オン、２−ベンジル−２−Ｎ，Ｎ−ジメチルアミノ−１−（４−モルフォリノフェニル）−１−ブタノン；ビス（２，４，６−トリメチルベンゾイル）−フェニルフォスフィンオキシドビス−（２，６−ジメトキシベンゾイル）−２，４，４−トリメチルペンチルフォスフィンオキシド；ビス（η５−シクロペンタジエニル）−ビス（ペンタフルオロフェニル）−チタニウム、ビス（η５−シクロペンタジエニル）−ビス［２，６−ジフルオロ−３−（１Ｈ−ピリ−１−イル）フェニル］−チタニウム；アントラセン、ペリレン、コロネン、テトラセン、ベンズアントラセン、フェノチアジン、フラビン、アクリジン、ケトクマリン、チオキサントン誘導体、ベンゾフェノン、アセトフェノン、２−クロロチオキサンソン、２，４−ジメチルチオキサンソン、２，４−ジエチルチオキサンソン、２，４−ジイソプロピルチオキサンソン、イソプロピルチオキサンソン等が挙げられる。これらは単独で用いられてもよいし、２種以上が併用されてもよい。
【００４５】
上記ポリオキシアルキレン樹脂組成物は、必要に応じてアルキルシラン化合物又はアルコキシシラン化合物を含有してもよい。上記アルキルシラン化合物又はアルコキシシラン化合物としては、例えば、ジメトキシジメチルシラン、シクロヘキシルジメトキシメチルシラン、ジエトキシジメチルシラン、ジメトキシメチルオクチルシラン、ジエトキシメチルビニルシラン、クロロメチル（ジイソプロポキシ）メチルシラン、ジメトキシメチルフェニルシラン、ジエトキシジフェニルシラン、トリメトキシシラン、トリエトキシシラン、メチルトリメトキシシラン、トリメトキシプロピルシラン、イソブチルトリメトキシシラン、オクチルトリメトキシシラン、オクタデシルトリメトキシシラン、メチルトリエトキシシラン、エチルトリエトキシシラン、イソブチルトリエトキシシラン、オクチルトリエトキシシラン、ビニルトリメトキシシラン、ビニルトリエトキシシラン、アリルトリエトキシシラン、（３−クロロプロピル）トリメトキシシラン、クロロメチルトリエトキシシラン、トリス（２−メトキシエトキシ）ビニルシラン、３−グリシドキシプロピルトリメトキシシラン、ジエトキシ（３−グリシドキシプロピル）メチルシラン、クロロトリメトキシシラン、クロロトリエトキシシラン、クロロトリス（１，３−ジメチルブトキシ）−シラン、ジクロロジエトキシシラン、３−（トリエトキシシリル）−プロピオニトリル、４−（トリエトキシシリル）−ブチロニトリル、３−（トリエトキシシリル）−プロピルイソシアネート、３−（トリエトキシシリル）−プロピルチオイソシアネート、フェニルトリメトキシシラン、フェニルトリエトキシシラン、テトラメトキシシラン、テトラエトキシシラン、テトラプロポキシシラン、テトラブトキシシラン、１，３，５，７−テトラエトキシ−１，３，５，７−テトラメチルシクロテトラシロキサン、１，３，５，７−テトラメチル−１，３，５，７−テトラプロキシシクロテトラシロキサン、１，３，５，７−テトライソプロポキシ−１，３，５，７−テトラメチルシクロテトラシロキサン、１，３，５，７−テトラブトキシ−１，３，５，７−テトラメチルシクロテトラシロキサン、１，３，５，７，９−ペンタエトキシ−１，３，５，７，９−ペンタメチルシクロペンタシロキサン、オクタメチルシクロテトラシロキサン、デカメチルシクロペンタシロキサン、ドデカメチルシクロヘキサシロキサン、ヘキサフェニルシクロトリシロキサン、オクタフェニルシクロテトラシロキサン、１，３，５，７−テトラメチルシクロテトラシロキサン、１，３，５，７−テトラメチル−１，３，５，７−テトラフェニルシクロテトラシロキサン、１，１，３，３，５，５−ヘキサメチルシクロトリシラザン、１，１，３，３，５，５，７，７−オクタメチルシクロテトラシラザン、１，７−ジアセトキシオクタメチルテトラシロキサン、１，７−ジクロロオクタメチルテトラシロキサン、１，１，３，３，５，５−ヘキサメチル−１，５−ジクロロトリシロキサン、１，３−ジクロロテトライソプロピルジシロキサン、１，３−ジエトキシテトラメチルジシロキサン、１，３−ジメトキシテトラメチルジシロキサン、１，１，３，３−テトラメチル−１，３−ジクロロジシロキサン、１，２−ビス（メチルジクロロシリル）エタン、ジアセトキシジフェニルシラン、メチルトリス（エチルメチルケトオキシム）シラン、メチルトリス（Ｎ，Ｎ−ジエチルアミノキシ）シラン、ビス（エチルメチルケトオキシム）メチルイソプロポキシシラン、ビス（エチルメチルケトオキシム）エトキシメチルシラン、トリス（１−メチルビニロキシ）ビニルシラン、メチルトリイソプロペノキシシラン、エチルトリアセトキシシラン、メチルトリアセトキシシラン、ジアセトキシジメチルシラン、トリアセトキシビニルシラン、テトラアセトキシシラン、ジアセトキシメチルフェニルシラン、ジメトキシエチルメチルケトオキシムメチルシラン等が挙げられる。
【００４６】
上記ポリオキシアルキレン樹脂組成物には、有機過酸化物が含有されていてもよい。有機過酸化物の含有により、加熱消滅性材料の加熱により消滅に至るまでの時間を短縮することができる。
【００４７】
上記有機過酸化物としては、例えば、ｐ−メンタンハイドロキシパーオキサイド、ジイソプロピルベンゼンハイドロキシパーオキサイド、１，１，３，３−テトラメチルブチルハイドロキシパーオキサイド、クメンハイドロキシパーオキサイド、ｔ−ヘキシルハイドロキシパーオキサイド、ｔ−ブチルハイドロキシパーオキサイド等のハイドロキシパーオキサイド；ジクミルパーオキサイド、α、α’−ビス（ｔ−ブチルパーオキシ−ｍ−イソプロピルベンゼン）、２，５−ジメチル−２，５−ビス（ｔ−ブチルパーオキシ）ヘキサン、ｔ−ブチルクミルパーオキサイド、ジ−ｔ−ブチルパーオキサイド、２，５−ジメチル−２，５−ビス（ｔ−ブチルパーオキシ）ヘキシン−３等のジアルキルパーオキサイド；１，１−ビス（ｔ−ヘキシルパーオキシ）−３，３，５−トリメチルシクロヘキサン、１，１−ビス（ｔ−ヘキシルパーオキシ）シクロヘキサン、１，１−ビス（ｔ−ブチルパーオキシ）−３，３，５−トリメチルシクロヘキサン、１，１−ビス（ｔ−ブチルパーオキシ）シクロヘキサン、１，１−ビス（ｔ−ブチルパーオキシ）シクロドデカン、２，２−ビス（ｔ−ブチルパーオキシ）ブタン、ｎ−ブチル４，４−ビス（ｔ−ブチルパーオキシ）バレレート、２，２−ビス（４，４−ジ−ｔ−ブチルパーオキシシクロヘキシル）プロパン等のパーオキシケタール；ｔ−ヘキシルパーオキシイソプロピルモノカーボネート、ｔ−ブチルパーオキシマレイン酸、ｔ−ブチルパーオキシ３，５，５−トリメチルヘキサノエート、ｔ−ブチルパーオキシラウレート、２，５−ジメチル−２，５−ビス（ｍ−トルイルパーオキシ）ヘキサン、ｔ−ブチルパーオキシイソプロピルモノカーボネート、ｔ−ヘキシルパーオキシベンゾエート、２，５−ジメチル−２，５−ビス（ｍ−ベンゾイルパーオキシ）ヘキサン、ｔ−ブチルパーオキシアセテート、ｔ−ブチルパーオキシベンゾエート、ビス−ｔ−ブチルパーオキシイソフタレート、ｔ−ブチルパーオキシアリルモノカーボネート等のパーオキシエステル等が挙げられる。
【００４８】
また、低融点の有機酸は、導電膜に対して洗浄作用を有するため、低融点の有機酸を上記ポリオキシアルキレン樹脂組成物に含有させておいてもよい。それによって、導電膜２，３の表面の酸化膜の除去が可能となり、熱消滅時の加熱による導電膜の酸化を防止することができる。
【００４９】
上記ポリオキシアルキレン樹脂組成物は、更に、必要に応じて、架橋促進剤、増粘剤、チキソトロープ剤、物性調整剤、増量剤、補強剤、可塑剤、着色剤、難燃剤等の各種添加剤を加えても良い。ただし、不燃性の添加剤は残留残さとなるため注意する必要がある。
【００５０】
上記架橋促進剤としては、例えば、ジブチル錫ジラウレート、ジブチル錫オキサイド、ジブチル錫ジアセテート、ジブチル錫フタレート、ビス（ジブチル錫ラウリン酸）オキサイド、ジブチル錫ビスアセチルアセトナート、ジブチル錫ビス（モノエステルマレート）、オクチル酸錫、ジブチル錫オクトエート、ジオクチル錫オキサイド等の錫化合物、テトラ−ｎ−ブトキシチタネート、テトライソプロポキシチタネート等のアルキルオキシチタネート等が挙げられる。ただし、これらの架橋促進剤は、必ず残留残さとなることから、必要最小限の添加に止めるべきである。
【００５１】
上記増粘剤は、上記ポリオキシアルキレン樹脂組成物の粘性特性を調整するために添加するものである。上記増粘剤としては、上記ポリオキシアルキレン樹脂との相溶性の高い高分子化合物から適宜選択され、例えば、アクリル系高分子、メタクリル系高分子、ポリビニルアルコール誘導体、ポリ酢酸ビニル、ポリスチレン誘導体、ポリエステル類、ポリエーテル類、ポリイソブテン、ポリオレフィン類、ポリアルキレンオキシド類、ポリウレタン類、ポリアミド類、天然ゴム、ポリブタジエン、ポリイソプレン、ＮＢＲ、ＳＢＳ、ＳＩＳ、ＳＥＢＳ、水添ＮＢＲ、水添ＳＢＳ、水添ＳＩＳ、水添ＳＥＢＳ等やこれら共重合体の官能基変成体が挙げられる。これらの増粘剤は単独で用いられてもよいし、２種以上が併用されてもよい。
【００５２】
上記チキソトロープ剤は、上記ポリオキシアルキレン樹脂組成物の粘性特性を調整するために添加するものである。上記チキソトロープ剤としては、例えば、コロイダルシリカ、ポリビニルピロリドン、疎水化炭酸カルシウム、ガラスバルーン、ガラスビーズ等が挙げられる。また、上記チキソトロープ剤は、上記ポリオキシアルキレン樹脂と親和性の高い表面を有するものが好ましい。
【００５３】
上記物性調整剤は、上記ポリオキシアルキレン樹脂組成物を用いた加熱消滅性材料の引張り特性等を改善するために添加するものである。上記物性調整剤としては、例えば、ビニルトリメトキシシラン、ジメチルジメトキシシラン、メチルトリメトキシシラン、メチルトリエトキシシラン、テトラメトキシシラン、テトラエトキシシラン、フェニルトリメトキシシラン、ジフェニルジメトキシシラン、３−アミノプロピルトリメトキシシラン、３−アミノプロピルメチルジメトキシシラン、３−アミノプロピルトリエトキシシラン、Ｎ−（２−アミノエチル）−３−アミノプロピルトリメトキシシラン、Ｎ−（２−アミノエチル）−３−アミノプロピルトリエトキシシラン、Ｎ，Ｎ’−ビス−［３−（トリメトキシシリル）プロピル］エチレンジアミン、Ｎ，Ｎ’−ビス−［３−（トリエトキシシリル）プロピル］エチレンジアミン、Ｎ，Ｎ’−ビス−［３−（トリメトキシシリル）プロピル］ヘキサエチレンジアミン、Ｎ，Ｎ’−ビス−［３−（トリエトキシシリル）プロピル］ヘキサエチレンジアミン等の各種シランカップリング剤等が挙げられる。これらの物性調整剤は単独で用いられてもよいし、２種以上が併用されてもよい。
【００５４】
上記増量剤としては特に限定されないが、上記ポリオキシアルキレン樹脂組成物のチキソトロープ性等への影響の少ないものが好適であり、例えば、タルク、クレー、炭酸カルシウム、炭酸マグネシウム、無水珪素、含水珪素、ケイ酸カルシウム、二酸化チタン、カーボンブラック等が挙げられる。これらの増量剤は単独で用いられてもよいし、２種以上が併用されてもよい。
【００５５】
上記可塑剤としては、例えば、リン酸トリブチル、リン酸トリクレジル等のリン酸エステル類、フタル酸ジオクチル等のフタル酸エステル類、グリセリンモノオレイル酸エステル等の脂肪酸−塩基酸エステル類、アジピン酸ジオクチル等の脂肪酸二塩基酸エステル類、ポリプロピレングリコール類等が挙げられる。これらの可塑剤は単独で用いられてもよいし、２種以上が併用されてもよい。
【００５６】
上記ポリオキシアルキレン樹脂組成物は、更に、必要に応じてタレ防止剤、酸化防止剤、老化防止剤、紫外線吸収剤、溶剤、香料、顔料、染料等が添加されてもよい。
【００５７】
上記加熱消滅性材料において、上記ポリオキシアルキレン樹脂組成物を架橋する際の光照射に用いる光源については特に限定されない。例えば、低圧水銀灯、中圧水銀灯、高圧水銀灯、超高圧水銀灯、エキシマーレーザー、ケミカルランプ、ブラックライトランプ、マイクロウェーブ励起水銀灯、メタルハライドランプ、ナトリウムランプ、ハロゲンランプ、キセノンランプ、蛍光灯、太陽光、電子線照射装置などを用いることができ、これらの光源は単独で用いられてもよく、２種以上を併用されてもよい。
【００５８】
本発明に係る回路基板の製造方法は、様々な基板の製造に適用することができる。図３は、本発明の第２の実施形態に係る回路基板の製造方法を説明するための正面断面図である。第２の実施形態では、回路基板としての多層基板２１が製造される。多層基板２１では、複数の基板本体２２〜２４が接着剤により貼り合わされて積層され、多層基板が構成されている。多層基板２１の製造に対しては、下面に導電膜２５、上面に電極２６が形成された基板本体２２と、上面に電極２７が形成された基板本体２３と、上面の全面に導電膜２８が形成された基板本体２４とが接着剤（図示せず）を用いて貼り合わされる。
【００５９】
なお、電極２６，２７は、基板本体２２〜２４に構成された他の回路部分（図示せず）に電気的に接続されており、かつ電極２６，２７は、グラウンド電位に接続される端子電極を構成している。
【００６０】
他方、導電膜２５，２８もグラウンド電位に接続される導電膜であり、多層基板２１の上面及び下面間の構造を電磁シールドする機能をも果たしている。
多層基板２１の製造に際しては、上記基板本体２２〜２４が貼り合わされた積層体が得られた後、第１の貫通孔２９及び第２の貫通孔３０，３１が形成される。第１の貫通孔２９には、めっき工程により導電膜３２が形成される。そして、導電膜３２の形成に先立ち、第２の貫通孔３０，３１には、第１の実施形態の場合と同様に加熱消滅性材料が充填される。そして、導電膜３２を形成した後に、第１の実施形態の場合と同様に、加熱消滅性材料が消滅する温度に加熱されて、第２の貫通孔３０，３１が露出される。
【００６１】
本実施形態においても、導電膜３２の形成に際しては、第２の貫通孔３０，３１が加熱消滅性材料で充填されているため、第２の貫通孔３０，３１への導電膜の付着を防止することができる。
【００６２】
そして、最終的に第２の貫通孔３０，３１に、第１の実施形態と同様にボルトが挿通され、多層基板２１が他のデバイスに固定される。
なお、導電膜３２は、上述した電極２６，２７に電気的に接続され、かつ導電膜２５，２８にも電気的に接続される。すなわち、導電膜３２は、電極２６，２７をグラウンド電位に接続される導電膜２５，２８に電気的に接続する接続電極として機能する。
【００６３】
なお、多層基板２１では、導電膜３２は、上記のように多層基板２１内に構成された回路部分の内のグラウンド電位に接続される端子電極としての電極２６，２７を外部に引き出す機能を果たしているが、半田ペースト３３を介して、半田ボール３４を導電膜３２に接合し、それによって放熱効果を高めるように構成してもよい。すなわち、本発明において、第１の貫通孔に形成される導電膜は、内部の電極を電気的に接続する機能だけでなく、放熱効果を高めるための熱媒体として形成されるものであってもよい。
【００６４】
また、本発明において製造される回路基板の電極の配置及びパターンは、目的とする回路基板に応じて適宜変更することができ、上記第１，第２の実施形態の構造に限定されるものではない。さらに、第１，第２の実施形態では、加熱消滅性材料が充填される第２の貫通孔はボルト孔であったが、ボルト孔以外の用途に用いられるものであってもよい。すなわち、導電膜の形成等の加工処理に際してブロックすべき貫通孔を有する回路基板の製造方法を一般に本発明を適用することができる。また、上記加熱消滅性材料で貫通孔をブロックした状態で行われる加工工程についても、導電膜の形成に限らず、抵抗膜の形成等の様々な加工工程を含むものとする。
【００６５】
【発明の効果】
本発明に係る回路基板の製造方法では、貫通孔に加熱消滅性材料を充填した後に、加熱消滅性材料が消滅する温度よりも低い温度雰囲気で加工処理が行われ、しかる後、加工処理された回路基板が加熱消滅性材料が消滅する温度以上に加熱される。従って、加熱消滅性材料が加熱により消滅し、上記貫通孔が露出する。よって、従来手作業で取り外されていたゴム栓に代えて、上記加熱消滅性材料を用いることにより、回路基板の製造工程の生産性を飛躍的に高めることが可能となり、回路基板のコストを低減することができる。
【００６６】
本発明において、加熱消滅性材料が充填される貫通孔と別の第２の貫通孔が形成され、加工工程において、第２の貫通孔の内周面を覆うように、あるいは第２の貫通孔に充填されるように導電性材料が第２の貫通孔に付与される場合には、本発明に従って、スルーホール電極やビアホール電極を有する回路基板を容易に得ることができる。
【００６７】
本発明において、加熱消滅性材料が充填される貫通孔が、回路基板を固定するためのボルト孔である場合には、本発明に従って、他のデバイスに容易に固定し得る回路基板を高い生産性で製造することが可能となる。
【００６８】
本発明において、上記加熱消滅性材料として、架橋性シリル基を有するポリオキシアルキレン樹脂を架橋させてなる樹脂を主成分とする材料を用いた場合には、１５０〜２６０℃の低い温度で加熱消滅性材料を消滅させることができる。従って、回路基板の製造に際し、他の部分に熱による損傷や劣化を与えることなく、回路基板を製造することができる。
【図面の簡単な説明】
【図１】（ａ）〜（ｄ）は、本発明の第１の実施形態に係る回路基板の製造方法の各正面断面図。
【図２】第１の実施形態で用いられる回路基板の処理前の状態を示す正面図。
【図３】本発明の第２の実施形態に係る回路基板の製造方法を説明するための正面断面図。
【符号の説明】
１…絶縁性基板
２，３…導電膜
４…第１の貫通孔
５，６…第２の貫通孔
７，８…加熱消滅性材料
９…導電膜
１１，１２…ボルト
２１…多層基板
２２〜２４…基板本体
２５，２８…導電膜
２６，２７…電極
２９…第１の貫通孔
３０，３１…第２の貫通孔
３２…導電膜
３３…半田ペースト
３４…半田ボール[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of manufacturing a circuit board, and more particularly, to a circuit board including a step of filling a through hole to be processed in a manufacturing process with a heat extinguishing material and removing the heat extinguishing material after the processing. And a method for producing the same.
[0002]
[Prior art]
Conventionally, in a circuit board such as a multilayer wiring board, a through-hole electrode or a via-hole electrode has been used to electrically connect electrodes on an upper surface and a lower surface or to electrically connect electrodes formed in an intermediate layer. I have. The through-hole electrode and the via-hole electrode are formed by forming a through-hole in an insulating substrate and forming a conductive film in the through-hole, or filling the through-hole with a conductive material.
[0003]
By the way, in a circuit board, in addition to a via-hole electrode and a through-hole electrode, a through-hole as a bolt hole for fixing the circuit board to another device with a bolt or a screw may be formed. When manufacturing a circuit board having such a bolt hole and the above-described through-hole electrode or via-hole electrode, first, a first through-hole for forming a through-hole electrode or a via-hole electrode and a bolt hole are formed in the substrate. A second through hole is formed at the same time. The first and second through holes may be formed separately. Next, a processing step of forming a conductive film in the first through hole by plating or the like or filling a conductive material in the second through hole is performed. In this processing step, in order to prevent the conductive material from adhering to the inner surface of the second through-hole, the above-described processing has been conventionally performed with the first through-hole closed with a rubber stopper. Thereafter, after the conductive film was formed, the rubber stopper was manually removed.
[0004]
A method for manufacturing such a circuit board is described in, for example, Patent Document 1 below.
[0005]
[Patent Document 1]
Japanese Patent Application Laid-Open No. Hei 10-326964
[Problems to be solved by the invention]
In the above method of manufacturing a circuit board, the rubber stopper had to be manually removed after forming the conductive film in the first through hole or filling the conductive material. Therefore, the operation process is complicated, and the cost of the circuit board has to be high.
[0007]
An object of the present invention is to provide a method of manufacturing a circuit board having a through-hole that should not be processed in view of the above-mentioned state of the art, and to protect the through-hole so as not to be affected by the processing during the processing. It is another object of the present invention to provide a method for manufacturing a circuit board, which includes a step which can release the protection of the through-hole easily after the processing.
[0008]
[Means for Solving the Problems]
A method of manufacturing a circuit board according to the present invention includes a step of preparing an insulating substrate provided with at least one electrode; a step of forming a through hole in the insulating substrate; Filling, and processing the insulating substrate filled with the heat-dissipating material in an atmosphere at a temperature lower than the temperature at which the heat-dissipating material disappears, and heat-dissipating the processed insulating substrate. Heating to a temperature equal to or higher than the temperature at which the conductive material disappears, extinguishing the heat-dissipating material, and exposing the through-hole.
[0009]
In a specific aspect of the method for manufacturing a circuit board according to the present invention, the method further includes, before the processing step, a step of forming a second through-hole different from the through-hole filled with the heat annihilation material. In the processing step, a conductive material is applied to the second through-hole so as to cover an inner peripheral surface of the second through-hole or to fill the second through-hole.
[0010]
In another specific aspect of the method for manufacturing a circuit board according to the present invention, the through hole filled with the heat annihilation material includes a bolt for fixing the circuit board after the heat annihilation material is removed. Bolt holes.
[0011]
In the method for manufacturing a circuit board according to the present invention, the circuit board may be a single-layer board or a multilayer board.
In the method for manufacturing a circuit board according to the present invention, preferably, the heat quenching material is a material mainly composed of a resin obtained by crosslinking a polyoxyalkylene resin having a crosslinkable silyl group.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.
[0013]
1A to 1D and FIG. 2 are a front sectional view and a front view for explaining a method for manufacturing a circuit board according to the first embodiment of the present invention.
In the present embodiment, first, the insulating substrate 1 shown in FIG. 2 is prepared. Conductive films 2 and 3 are formed on the entire upper and lower surfaces of the insulating substrate 1. The insulating substrate 1 is made of a known substrate material. That is, the substrate 1 can be made of, for example, a synthetic resin or a synthetic resin composite material such as a glass epoxy-based material, an epoxy resin, or a polyimide, or an insulating ceramic.
[0014]
The conductive films 2 and 3 are made of a metal or an alloy such as Cu or Au, and the conductive films 2 and 3 can be formed by an appropriate method such as vapor deposition, plating or sputtering, or printing of a conductive paste.
[0015]
Next, as shown in FIG. 1A, a first through hole 4 and second through holes 5 and 6 are formed in the insulating substrate 1. In the present embodiment, the first through-hole 4 and the second through-holes 5 and 6 are formed at the same time to simplify the working process.
[0016]
The first through-hole 4 and the second through-holes 5 and 6 can be formed by various methods such as processing by a laser and processing by a mechanical processing device such as a drill.
In the present embodiment, the second through holes 5 and 6 are provided as bolt holes for finally fixing the circuit board to another device, as described later. Further, as shown in the following steps, a conductive film is formed in the first through hole 4 to form a through-hole electrode.
[0017]
Next, as shown in FIG. 1B, the second through holes 5 and 6 are filled with heat-destructible materials 7 and 8, respectively.
The heat extinguisher materials 7 and 8 are made of a material that does not disappear at a processing temperature of a conductive film forming step, that is, a processing step described later. In the present embodiment, the heat extinguisher materials 7 and 8 are made of a material described later that disappears at a temperature of 150 to 260 ° C.
[0018]
Next, as shown in FIG. 1C, a conductive film 9 is formed in the first through hole 4 by plating. The conductive film 9 is formed so as to cover the inner peripheral surface of the first through hole 4 and to be electrically connected to the conductive film 2 on the upper surface and the conductive film 3 on the lower surface. During plating, the conductive film 9 is applied to the inner peripheral surface of the first through-hole 4, but the second through-holes 5, 6 are filled with the heat-extinguishing materials 7, 8. Is not provided. Thereafter, the insulating substrate 1 is heated to a temperature at which the heat-dissipating materials 7 and 8 disappear, that is, 150 to 260 ° C. As a result, as shown in FIG. 1D, the heat extinguishing materials 7 and 8 are extinguished by heating, the second through holes 5 and 6 are exposed, and the circuit board of the present embodiment is obtained.
[0019]
In this embodiment, as shown in FIG. 1D, bolts 11 and 12 for fixing a circuit board to another device are inserted into the second through holes 5 and 6. As shown in FIG. 1D, in order to insulate the bolts 11 and 12 and the conductive films 2 and 3 from each other, an insulating material is inserted so as to be extrapolated to the threaded portions 11b and 12b of the bolts 11 and 12. Are used. The insulating cylinders 13 and 14 are configured to have an outer diameter that can be inserted into the through holes 5 and 6. Further, insulating washers 15 and 16 made of an insulating material are arranged between the heads 11 a and 12 a of the bolts 11 and 12 and the insulating cylinders 13 and 14. By using the insulating cylinders 13 and 14 and the insulating washers 15 and 16, electrical insulation between the bolts 11 and 12 and the conductive films 2 and 3 is achieved.
[0020]
The threaded portions 11b and 12b of the bolts 11 and 12 protrude further downward from the lower surface of the circuit board 1, that is, the surface on which the conductive film 3 is formed, and are screwed into another device (not shown). Fixed to the device.
[0021]
As described above, in the present embodiment, prior to performing the processing step of forming the first through hole 4 and the second through holes 5 and 6 and forming the conductive film 9 only in the first through hole 4. The second through-holes 5 and 6 are filled with heat extinguishing materials 7 and 8, respectively. Therefore, when the conductive film 9 is formed, the conductive film can be reliably prevented from adhering to the through-holes 5 and 6. 7, 8 can be easily removed.
[0022]
Therefore, the productivity of the circuit board can be drastically improved by using the above-mentioned heat annihilation materials 7 and 8 instead of the rubber stopper which has been conventionally manually removed.
[0023]
As the heat annihilation materials 7 and 8, an appropriate heat annihilation material that can be extinguished at the forming temperature of the conductive film 9, that is, at the processing temperature of the processing step, can be used. A heat extinguishing material that extinguishes at a temperature of up to 260 ° C. is used. Since it disappears by heating at a relatively low temperature of 150 to 260 ° C., it is difficult to damage the conductive films 2, 3, 9 or the insulating substrate 1 by heating.
[0024]
Further, in the present embodiment, only the conductive films 2, 3, and 9 are formed as electrodes for ease of explanation. However, in the case where electrodes or circuit elements of other complicated shapes are incorporated, It is sufficient to select a heat-dissipating material that dissipates at a low processing temperature of 150 to 260 ° C., and the effect of suppressing damage to the circuit board is further increased.
[0025]
Examples of the heat annihilating materials 7 and 8 include polymethylenemalonic diester, polybutylene, nitrocellulose, α-methylstyrene polymer, propylene carbonate polymer, poly (meth) acrylic acid alkyl ester, carboxylic acid dihydrazide and diisocyanate. There are known copolymers obtained by polymerizing the above compounds or peroxides of these polymers. Further, a heat-extinguishing material obtained by adding a plasticizer such as dibutyl phthalate or dioctyl phthalate, or a softening agent such as xylene oil, terpene oil or paraffin wax to the polymer, as necessary, to impart tackiness has been known. . These known heat annihilation materials can be used in the present embodiment in the case where the temperature at which the heat annihilation material is annihilated is not reduced. These heat extinguishing materials disappear by heating to a temperature of about 270 to 400 ° C.
[0026]
However, in the present embodiment, a specific heat annihilation material is preferably used in order to annihilate the heat annihilation materials 7 and 8 at a relatively low temperature of 150 to 260 ° C. as described above. Such a heat quenching material has been conceived by the present inventors, and contains a resin obtained by crosslinking a polyoxyalkylene resin having a crosslinkable silyl group as a main component.
[0027]
The polyoxyalkylene resin is not particularly limited, and includes, for example, polyoxypropylene, polyoxyethylene, polyoxytetramethylene and the like. Also, by combining various polyoxyalkylenes, it is possible to adjust the heating extinction temperature and the time until the extinction.
[0028]
In particular, in a composition containing 50% by weight or more of polyoxypropylene and mixed with polyoxyethylene or polyoxytetramethylene, the heating extinction temperature is adjusted by adjusting the mixing ratio of the polyoxyethylene or polyoxytetramethylene. In addition, the time until the heat disappears can be easily adjusted.
[0029]
Examples of the crosslinkable silyl group include an oximesilyl group, an alkenyloxysilyl group, an acetoxysilyl group, a halogenosilyl group, a vinylsilyl group, and a silanol group. Among them, a polyoxyalkylene resin having an alkoxysilyl group at a terminal is preferable because it becomes a rubbery crosslinked resin having excellent elasticity.
[0030]
Examples of the alkoxysilyl group include a methoxysilyl group, an ethoxysilyl group, a propyloxysilyl group, an isopropyloxysilyl group, a butoxysilyl group, a tert-butoxysilyl group, a phenoxysilyl group, and a benzyloxysilyl group. In the case of a dialkoxysilyl group or trialkoxysilyl group, they may be the same alkoxy group or a combination of different alkoxy groups. These crosslinkable silyl groups may be used alone or in combination of two or more. Further, a plurality of types of polyoxyalkylene resins having different types of polyoxyalkylene resins and different crosslinkable silyl groups may be used in combination.
[0031]
It is preferable that the polyoxyalkylene resin composition further contains a photoreaction catalyst having a functional group represented by the following formula (1). Thereby, the polyoxyalkylene resin composition can be cross-linked and cured by irradiating light such as visible light, ultraviolet light, and electron beam (hereinafter, also referred to as light irradiation). Among them, carboxylic acid anhydrides, carboxylic acid imides and diacylphosphine oxides are preferred because of their high photoreactivity and excellent solubility in a polyoxyalkylene resin having a crosslinkable silyl group. Such photoreaction catalysts may be used alone or in combination of two or more.
[0032]
In addition, when diacylphosphine oxide is contained, the residue after disappearance is extremely small, which is more preferable.
[0033]
Embedded image

[0034]
In the formula (1), m represents an integer of 2 to 5, Y ^(m) represents an atom of Group IVB, VB or VIB of the periodic table, and Z represents a hydrogen group, a hydrocarbon group, a mercapto group, an amino group. Represents a group, a halogen group, an alkoxyl group, an alkylthio group, a carbonyloxy group or an oxo group.
[0035]
The photoreaction catalyst having a functional group represented by the above formula (1) may have a plurality of different functional groups represented by the general formula (1).
Examples of the photoreaction catalyst having a functional group represented by the above general formula (1) include, for example, carbonyl with respect to an atom represented by Y ^(m) selected from the group consisting of oxygen, sulfur, nitrogen, phosphorus and carbon. A compound in which two groups are bonded to each other, which has a hydrocarbon group or an oxide group represented by Z as appropriate according to the valence of the atom represented by Y ^(m) , and the like can be given.
[0036]
Examples of the hydrocarbon group include an aliphatic hydrocarbon group, an unsaturated aliphatic hydrocarbon group, and an aromatic hydrocarbon group. These hydrocarbon groups have a substituent such as an amino group, a hydroxyl group, an ether group, an epoxy group, a polymerizable unsaturated group, a urethane group, a urea group, an imide group, an ester group or the like within a range not to impair the object of the present invention. May be. Further, different hydrocarbon groups may be used in combination.
[0037]
The photoreaction catalyst having a functional group represented by the above formula (1) may be a cyclic compound. Examples of such a cyclic compound include compounds having one or two or more of the same or different functional groups represented by the general formula (1) in a cyclic chain. Further, a compound in which a plurality of the same or different cyclic compounds are bonded by an appropriate organic group, a bicyclic compound containing at least one or more of the same or different cyclic compounds as a unit, or the like can also be used. .
[0038]
As the photoreaction catalyst having a functional group represented by the above formula (1), when the atom represented by Y ^(m) is an oxygen atom, for example, acetic anhydride, propionic anhydride, butyric anhydride Anhydride, isobutylic anhydride, valeric anhydride, 2-methylbutyric anhydride, trimethylacetic anhydride, hexanoic anhydride, heptanoic anhydride, decanoic anhydride, lauric anhydride, myristylic anhydride, palmitic anhydride Acid anhydride, stearyl anhydride, docosanoic anhydride, crotonic anhydride, acrylic anhydride, methacrylic anhydride, oleic anhydride, linoleic anhydride, chloroacetic anhydride, iodoacetic anhydride, dichloro Acetic anhydride, trifluoroacetic anhydride, chlorodifluoroacetic anhydride, trichloroacetic anhydride, pentafluoropropionic anhydride, heptafluoro Butyric anhydride, succinic anhydride, methyl succinic anhydride, 2,2-dimethylsuccinic anhydride, isobutyl succinic anhydride, 1,2-cyclohexanedicarboxylic anhydride, hexahydro-4-methylphthalic anhydride, Itaconic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, maleic anhydride, 2-methylmaleic anhydride, 2,3- Dimethylmaleic anhydride, 1-cyclopentene-1,2-dicarboxylic anhydride, glutaric anhydride, 1-naphthylacetic anhydride, benzoic anhydride, phenylsuccinic anhydride, phenylmaleic anhydride, 2, 3-diphenylmaleic anhydride, phthalic anhydride, 4-methylphthalic anhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid , 4,4 '-(hexafluoropropylidene) diphthalic anhydride, 1,2,4,5-benzenetetracarboxylic anhydride, 1,8-naphthalenedicarboxylic anhydride, 1,4,5,8 -Naphthalenetetracarboxylic anhydride and the like; as a copolymer of maleic anhydride and a compound having a radical polymerizable double bond, for example, a copolymer of maleic anhydride and (meth) acrylate, maleic anhydride, Examples include styrene copolymers and copolymers of maleic anhydride and vinyl ether. Among these, commercially available products include, for example, Adeka Hardener EH-700, Adeka Hardener EH-703, Adeka Hardener EH-705A manufactured by Asahi Denka Co., Ltd .; RIKACID MH-700, RIKACID MH-700H, RIKACID MH, RIKACID SH, RIKARESIN TMEG; HN-5000, HN-2000, manufactured by Hitachi Chemical Co., Ltd .; Sumi Cure MS manufactured by Sumitomo Chemical Co., Ltd .;
[0039]
When the atom represented by Y ^(m) is a nitrogen atom, the photoreaction catalyst having a functional group represented by the above formula (1) is, for example, succinimide, N-methylsuccinimide, α, α-dimethyl-β-methylsuccinimide, α-methyl-α-propylsuccinimide, maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-tert-butylmaleimide, N-laurylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N- (2-chlorophenyl) maleimide, N-benzylmaleimide, N- (1-pyrenyl) maleimide, 3-methyl-N-phenylmaleimide, N, N'-1,2 -Phenylenedimaleimide, N, N'-1,3-phenylenedimaleimide, N, N'-1,4-phenylenedimale Imide, N, N ′-(4-methyl-1,3-phenylene) bismaleimide, 1,1 ′-(methylenedi-1,4-phenylene) bismaleimide, phthalimide, N-methylphthalimide, N-ethylphthalimide, N-propylphthalimide, N-phenylphthalimide, N-benzylphthalimide, pyromellitic diimide and the like can be mentioned.
[0040]
As the photoreaction catalyst having a functional group represented by the above formula (1), when the atom represented by Y ^(m) is a phosphorus atom, for example, bis (2,6-dimethoxybenzoyl) -2, 4,4-trimethyl-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide and the like can be mentioned.
[0041]
As the photoreaction catalyst having a functional group represented by the above formula (1), when the atom represented by Y ^(m) is a carbon atom, for example, 2,4-pentanedione, 3-methyl-2 , 4-pentanedione, 3-ethyl-2,4-pentanedione, 3-chloro-2,4-pentanedione, 1,1,1-trifluoro-2,4-pentanedione, 1,1,1, Diketones such as 5,5,5-hexafluoro-2,4-pentanedione, 2,2,6,6-tetramethyl-3,5-heptanedione, 1-benzoylacetone and dibenzoylmethane; dimethylmalonate Polycarboxylic acid esters such as ethyl, diethyl malonate, dimethyl methyl malonate, tetraethyl 1,1,2,2-ethanetetracarboxylic acid; methyl acetylacetonate, ethyl acetylacetonate And α-carbonyl-acetic esters such as methylpropionyl acetate. Above all, diacylphosphine oxide and its derivatives are preferable since the residue after disappearance is extremely small.
[0042]
A preferred lower limit of the amount of the photoreaction catalyst having a functional group represented by the above formula (1) is 0.01 part by weight, and a preferred upper limit is 30 parts by weight, based on 100 parts by weight of a polyoxyalkylene resin having a crosslinkable silyl group. Parts by weight. If the amount is less than 0.01 part by weight, photoreactivity may not be exhibited. If the amount exceeds 30 parts by weight, the light transmittance of the polyoxyalkylene resin composition is reduced, and only the surface is exposed to light. May be cross-linked and cured, but not deeply cross-linked or cured. A more preferred lower limit is 0.1 part by weight, and a more preferred lower limit is 20 parts by weight.
[0043]
The polyoxyalkylene resin composition may contain a sensitizer. By containing a sensitizer, photoreactivity is improved, and the light irradiation time can be shortened, the light irradiation energy can be reduced, and crosslinking and curing can be performed uniformly from the surface to the deep part.
[0044]
Examples of the sensitizer include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α′-dimethylacetophenone, methoxyacetophenone, and 2,2-dimethoxy-. Acetophenone derivative compounds such as 2-phenylacetophenone; benzoin ether compounds such as benzoin ethyl ether and benzoin propyl ether; ketal derivative compounds such as benzyl dimethyl ketal; halogenated ketones; acylphosphine oxides; acylphosphonates; -1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-N, N-dimethylamino-1- (4-morpholinophenyl) -1-butanone; bis ( 2,4,6-trimethylben Yl) -phenylphosphine oxide bis- (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide; bis (η5-cyclopentadienyl) -bis (pentafluorophenyl) -titanium, bis (Η5-cyclopentadienyl) -bis [2,6-difluoro-3- (1H-pyrid-1-yl) phenyl] -titanium; anthracene, perylene, coronene, tetracene, benzanthracene, phenothiazine, flavin, acridine, Ketocoumarin, thioxanthone derivatives, benzophenone, acetophenone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, isopropylthioxanthone and the like Can be These may be used alone or in combination of two or more.
[0045]
The polyoxyalkylene resin composition may contain an alkylsilane compound or an alkoxysilane compound as needed. Examples of the above alkylsilane compound or alkoxysilane compound include dimethoxydimethylsilane, cyclohexyldimethoxymethylsilane, diethoxydimethylsilane, dimethoxymethyloctylsilane, diethoxymethylvinylsilane, chloromethyl (diisopropoxy) methylsilane, and dimethoxymethylphenylsilane , Diethoxydiphenylsilane, trimethoxysilane, triethoxysilane, methyltrimethoxysilane, trimethoxypropylsilane, isobutyltrimethoxysilane, octyltrimethoxysilane, octadecyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, isobutyl Triethoxysilane, octyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane , Allyltriethoxysilane, (3-chloropropyl) trimethoxysilane, chloromethyltriethoxysilane, tris (2-methoxyethoxy) vinylsilane, 3-glycidoxypropyltrimethoxysilane, diethoxy (3-glycidoxypropyl) ) Methylsilane, chlorotrimethoxysilane, chlorotriethoxysilane, chlorotris (1,3-dimethylbutoxy) -silane, dichlorodiethoxysilane, 3- (triethoxysilyl) -propionitrile, 4- (triethoxysilyl)- Butyronitrile, 3- (triethoxysilyl) -propyl isocyanate, 3- (triethoxysilyl) -propylthioisocyanate, phenyltrimethoxysilane, phenyltriethoxysilane, tetramethoxysilane, tetraethoxysilane , Tetrapropoxysilane, tetrabutoxysilane, 1,3,5,7-tetraethoxy-1,3,5,7-tetramethylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,3 5,7-tetraproxycyclotetrasiloxane, 1,3,5,7-tetraisopropoxy-1,3,5,7-tetramethylcyclotetrasiloxane, 1,3,5,7-tetrabutoxy-1,3 , 5,7-Tetramethylcyclotetrasiloxane, 1,3,5,7,9-pentaethoxy-1,3,5,7,9-pentamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, decamethylcyclopenta Siloxane, dodecamethylcyclohexasiloxane, hexaphenylcyclotrisiloxane, octaphenylcyclotetrasiloxane, 1 , 3,5,7-tetramethylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenylcyclotetrasiloxane, 1,1,3,3,5,5- Hexamethylcyclotrisilazane, 1,1,3,3,5,5,7,7-octamethylcyclotetrasilazane, 1,7-diacetoxyoctamethyltetrasiloxane, 1,7-dichlorooctamethyltetrasiloxane, 1 1,1,3,3,5,5-hexamethyl-1,5-dichlorotrisiloxane, 1,3-dichlorotetraisopropyldisiloxane, 1,3-diethoxytetramethyldisiloxane, 1,3-dimethoxytetramethyldisiloxane Siloxane, 1,1,3,3-tetramethyl-1,3-dichlorodisiloxane, 1,2-bis (methyldichlorosilyl) ethane, dia Toxidiphenylsilane, methyltris (ethylmethylketoxime) silane, methyltris (N, N-diethylaminoxy) silane, bis (ethylmethylketoxime) methylisopropoxysilane, bis (ethylmethylketoxime) ethoxymethylsilane, tris (1 -Methylvinyloxy) vinylsilane, methyltriisopropenoxysilane, ethyltriacetoxysilane, methyltriacetoxysilane, diacetoxydimethylsilane, triacetoxyvinylsilane, tetraacetoxysilane, diacetoxymethylphenylsilane, dimethoxyethylmethylketoximemethylsilane And the like.
[0046]
The polyoxyalkylene resin composition may contain an organic peroxide. By containing the organic peroxide, it is possible to shorten the time until the heat-dissipating material is extinguished by heating.
[0047]
As the organic peroxide, for example, p-menthane hydroxy peroxide, diisopropylbenzene hydroxy peroxide, 1,1,3,3-tetramethylbutyl hydroxy peroxide, cumene hydroxy peroxide, t-hexyl hydroxy peroxide, hydroxy peroxides such as t-butyl hydroxy peroxide; dicumyl peroxide, α, α'-bis (t-butylperoxy-m-isopropylbenzene), 2,5-dimethyl-2,5-bis (t- Dialkyl peroxides such as butylperoxy) hexane, t-butylcumyl peroxide, di-t-butyl peroxide, and 2,5-dimethyl-2,5-bis (t-butylperoxy) hexyne-3; 1-bis (t-hexylpa Oxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1-bis (t-butylperoxy) cyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) butane, n-butyl 4,4-bis ( Peroxyketals such as t-butylperoxy) valerate and 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane; t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid , T-butylperoxy 3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5-dimethyl 2,5-bis (m-toluylperoxy) hexane, t-butylperoxyisopropyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-bis (m-benzoylperoxy) Peroxyesters such as hexane, t-butylperoxyacetate, t-butylperoxybenzoate, bis-t-butylperoxyisophthalate, and t-butylperoxyallyl monocarbonate are exemplified.
[0048]
Further, since the low melting point organic acid has a cleaning effect on the conductive film, the low melting point organic acid may be contained in the polyoxyalkylene resin composition. This makes it possible to remove the oxide film on the surfaces of the conductive films 2 and 3 and prevent oxidation of the conductive film due to heating at the time of heat disappearance.
[0049]
The polyoxyalkylene resin composition further includes, if necessary, various additives such as a crosslinking accelerator, a thickener, a thixotropic agent, a physical property modifier, a bulking agent, a reinforcing agent, a plasticizer, a coloring agent, and a flame retardant. May be added. However, care must be taken because non-combustible additives remain as residues.
[0050]
Examples of the crosslinking accelerator include dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate, bis (dibutyltin laurate) oxide, dibutyltin bisacetylacetonate, and dibutyltin bis (monoester maleate). ), Tin compounds such as tin octylate, dibutyltin octoate and dioctyltin oxide, and alkyloxy titanates such as tetra-n-butoxytitanate and tetraisopropoxytitanate. However, since these crosslinking accelerators always remain as residues, they should be added to the minimum necessary amount.
[0051]
The thickener is added to adjust the viscosity characteristics of the polyoxyalkylene resin composition. The thickener is appropriately selected from high-molecular compounds having high compatibility with the polyoxyalkylene resin, for example, acrylic polymers, methacrylic polymers, polyvinyl alcohol derivatives, polyvinyl acetate, polystyrene derivatives, polyesters , Polyethers, polyisobutene, polyolefins, polyalkylene oxides, polyurethanes, polyamides, natural rubber, polybutadiene, polyisoprene, NBR, SBS, SIS, SEBS, hydrogenated NBR, hydrogenated SBS, hydrogenated SIS, Examples include hydrogenated SEBS and the like, and modified functional groups of these copolymers. These thickeners may be used alone or in combination of two or more.
[0052]
The thixotropic agent is added to adjust the viscosity characteristics of the polyoxyalkylene resin composition. Examples of the thixotropic agent include colloidal silica, polyvinylpyrrolidone, hydrophobized calcium carbonate, glass balloon, glass beads and the like. The thixotropic agent preferably has a surface having a high affinity for the polyoxyalkylene resin.
[0053]
The physical property modifier is added in order to improve the tensile properties and the like of the heat-destructible material using the polyoxyalkylene resin composition. Examples of the physical property modifier include vinyltrimethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, and 3-aminopropyltrimethylsilane. Methoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltri Ethoxysilane, N, N'-bis- [3- (trimethoxysilyl) propyl] ethylenediamine, N, N'-bis- [3- (triethoxysilyl) propyl] ethylenediamine, N, N'-bis- [3 -(Trimethoxysilyl) Propyl] hexaethylenediamine, N, N'-bis - [3- (triethoxysilyl) propyl] various silane coupling agents such as hexamethylene diamine and the like. These physical property modifiers may be used alone or in combination of two or more.
[0054]
The extender is not particularly limited, but those having little effect on the thixotropy and the like of the polyoxyalkylene resin composition are suitable.For example, talc, clay, calcium carbonate, magnesium carbonate, anhydrous silicon, hydrous silicon, Examples thereof include calcium silicate, titanium dioxide, and carbon black. These extenders may be used alone or in combination of two or more.
[0055]
Examples of the plasticizer include phosphates such as tributyl phosphate and tricresyl phosphate; phthalates such as dioctyl phthalate; fatty acid-basic acid esters such as glycerin monooleate; dioctyl adipate; Fatty acid dibasic acid esters, polypropylene glycols and the like. These plasticizers may be used alone or in combination of two or more.
[0056]
The polyoxyalkylene resin composition may further contain an anti-sagging agent, an antioxidant, an antioxidant, an ultraviolet absorber, a solvent, a fragrance, a pigment, a dye, and the like, if necessary.
[0057]
In the heat extinguisher material, the light source used for light irradiation when crosslinking the polyoxyalkylene resin composition is not particularly limited. For example, low-pressure mercury lamp, medium-pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, excimer laser, chemical lamp, black light lamp, microwave-excited mercury lamp, metal halide lamp, sodium lamp, halogen lamp, xenon lamp, fluorescent lamp, sunlight, electronic A line irradiation device or the like can be used, and these light sources may be used alone or in combination of two or more.
[0058]
The method for manufacturing a circuit board according to the present invention can be applied to the manufacture of various substrates. FIG. 3 is a front sectional view for explaining a method for manufacturing a circuit board according to the second embodiment of the present invention. In the second embodiment, a multilayer board 21 as a circuit board is manufactured. In the multilayer substrate 21, a plurality of substrate bodies 22 to 24 are bonded and laminated with an adhesive to form a multilayer substrate. For the manufacture of the multilayer substrate 21, a conductive film 25 is formed on the lower surface, a substrate body 22 having the electrode 26 formed on the upper surface, a substrate body 23 formed with the electrode 27 on the upper surface, and a conductive film 28 is formed on the entire upper surface. The formed substrate main body 24 is bonded using an adhesive (not shown).
[0059]
The electrodes 26 and 27 are electrically connected to other circuit parts (not shown) formed on the substrate bodies 22 to 24, and the electrodes 26 and 27 are terminal electrodes connected to the ground potential. Is composed.
[0060]
On the other hand, the conductive films 25 and 28 are also conductive films connected to the ground potential, and also function to electromagnetically shield the structure between the upper and lower surfaces of the multilayer substrate 21.
In manufacturing the multilayer substrate 21, after obtaining a laminate in which the substrate bodies 22 to 24 are bonded, first through holes 29 and second through holes 30, 31 are formed. The conductive film 32 is formed in the first through hole 29 by a plating process. Then, prior to the formation of the conductive film 32, the second through holes 30 and 31 are filled with a heat annihilation material as in the case of the first embodiment. Then, after forming the conductive film 32, the second through holes 30 and 31 are exposed by heating to a temperature at which the heat-dissipating material disappears, as in the first embodiment.
[0061]
Also in the present embodiment, since the second through-holes 30 and 31 are filled with the heat annihilation material when forming the conductive film 32, adhesion of the conductive film to the second through-holes 30 and 31 is prevented. can do.
[0062]
Finally, bolts are inserted through the second through holes 30 and 31 similarly to the first embodiment, and the multilayer board 21 is fixed to another device.
The conductive film 32 is electrically connected to the electrodes 26 and 27 described above, and is also electrically connected to the conductive films 25 and 28. That is, the conductive film 32 functions as a connection electrode that electrically connects the electrodes 26 and 27 to the conductive films 25 and 28 connected to the ground potential.
[0063]
In the multilayer substrate 21, the conductive film 32 has a function of drawing out the electrodes 26 and 27 as terminal electrodes connected to the ground potential in the circuit portions formed in the multilayer substrate 21 as described above. However, the configuration may be such that the solder balls 34 are joined to the conductive film 32 via the solder paste 33 to thereby enhance the heat radiation effect. That is, in the present invention, the conductive film formed in the first through-hole may be formed not only as a function of electrically connecting the internal electrodes but also as a heat medium for enhancing the heat radiation effect. Good.
[0064]
Further, the arrangement and pattern of the electrodes of the circuit board manufactured in the present invention can be appropriately changed according to the intended circuit board, and are not limited to the structures of the first and second embodiments. Absent. Furthermore, in the first and second embodiments, the second through-hole filled with the heat annihilation material is a bolt hole, but may be used for applications other than the bolt hole. That is, the present invention can be generally applied to a method of manufacturing a circuit board having a through hole to be blocked in a processing such as formation of a conductive film. Further, the processing steps performed in a state where the through-holes are blocked with the heat annihilating material are not limited to the formation of the conductive film, but include various processing steps such as formation of a resistance film.
[0065]
【The invention's effect】
In the method for manufacturing a circuit board according to the present invention, after filling the through hole with the heat annihilation material, the processing is performed in an atmosphere at a temperature lower than the temperature at which the heat annihilation material disappears, and thereafter, the processing is performed. The circuit board is heated to a temperature higher than the temperature at which the heat-dissipating material disappears. Therefore, the heat extinguishing material is extinguished by heating, and the through hole is exposed. Therefore, by using the above-mentioned heat-extinguishing material instead of the rubber stopper which has been conventionally removed manually, it is possible to dramatically increase the productivity of the circuit board manufacturing process and reduce the cost of the circuit board. can do.
[0066]
In the present invention, a second through hole different from the through hole filled with the heat annihilation material is formed, and in the processing step, the second through hole covers the inner peripheral surface of the second through hole or the second through hole. When a conductive material is applied to the second through-hole so as to be filled into the second through-hole, a circuit board having a through-hole electrode or a via-hole electrode can be easily obtained according to the present invention.
[0067]
In the present invention, when the through hole filled with the heat annihilation material is a bolt hole for fixing the circuit board, according to the present invention, a circuit board which can be easily fixed to another device can be manufactured with high productivity. Can be manufactured.
[0068]
In the present invention, when a material containing a resin obtained by crosslinking a polyoxyalkylene resin having a crosslinkable silyl group as a main component is used as the heat annihilation material, the heat annihilation occurs at a low temperature of 150 to 260 ° C. Conductive material can be extinguished. Therefore, when manufacturing the circuit board, the circuit board can be manufactured without damaging or degrading other parts due to heat.
[Brief description of the drawings]
FIGS. 1A to 1D are front sectional views of a method for manufacturing a circuit board according to a first embodiment of the present invention.
FIG. 2 is a front view showing a state before processing of a circuit board used in the first embodiment.
FIG. 3 is a front sectional view for explaining a method for manufacturing a circuit board according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Insulating substrate 2, 3 ... Conductive film 4 ... First through hole 5, 6 ... Second through hole 7, 8 ... Heat extinguishing material 9 ... Conductive film 11, 12 ... Bolt 21 ... Multilayer substrate 22 ~ 24 substrate main bodies 25 and 28 conductive films 26 and 27 electrodes 29 first through holes 30 and 31 second through holes 32 conductive films 33 solder paste 34 solder balls

Claims (5)

Providing an insulating substrate provided with at least one electrode;
Forming a through hole in the insulating substrate;
Filling the through hole with a heat-dissipating material;
A step of processing the insulating substrate filled with the heat annihilation material in an atmosphere at a temperature lower than the temperature at which the heat annihilation material disappears,
Heating the processed insulative substrate to a temperature at which the heat extinguisher material disappears, and exposing the through-holes by extinguishing the heat annihilable material. Production method. Prior to the processing step, the method further includes a step of forming a second through-hole different from the through-hole filled with the heat annihilation material,
The conductive material is provided to the second through-hole so as to cover an inner peripheral surface of the second through-hole or to fill the second through-hole in the processing step. 2. The method for manufacturing a circuit board according to item 1. The circuit board according to claim 1, wherein the through hole filled with the heat annihilation material is a bolt hole into which a bolt for fixing the circuit board is inserted after the heat annihilation material is removed. Manufacturing method. The method for manufacturing a circuit board according to claim 1, wherein the circuit board is a multilayer board. The method for manufacturing a circuit board according to claim 1, wherein the heat annihilation material is mainly composed of a resin obtained by crosslinking a polyoxyalkylene resin having a crosslinkable silyl group. 5. .

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